Rec

Distribution by Scientific Domains

Kinds of Rec

  • anat rec


  • Selected Abstracts


    Microbial colonization patterns predict the outcomes of surgical treatment of intrabony defects

    JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 1 2006
    Lisa Heitz-Mayfield
    Abstract Aim: To explore the impact of bacterial load and microbial colonization patterns on the clinical outcomes of periodontal surgery at deep intrabony defects. Materials and Methods: One hundred and twenty-two patients with advanced chronic periodontitis and at least one intrabony defect of >3 mm were recruited in 10 centres. Before recruitment, the infection control phase of periodontal therapy was completed. After surgical access and debridement, the regenerative material was applied in the test subjects, and omitted in the controls. At baseline and 1 year following the interventions, clinical attachment levels (CAL), pocket probing depths (PPD), recession (REC), full-mouth plaque scores and full-mouth bleeding scores were assessed. Microbial colonization of the defect-associated pocket was assessed using a DNA,DNA checkerboard analysis. Results: Total bacterial load and counts of red complex bacteria were negatively associated with CAL gains 1 year following treatment. The probability of achieving above median CAL gains (>3 mm) was significantly decreased by higher total bacterial counts, higher red complex and T. forsythensis counts immediately before surgery. Conclusions: Presence of high bacterial load and specific periodontal pathogen complexes in deep periodontal pockets associated with intrabony defects had a significant negative impact on the 1 year outcome of surgical/regenerative treatment. [source]


    Long-term stability of periodontal conditions achieved following guided tissue regeneration with bioresorbable membranes: case series results after 6,7 years

    JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 11 2004
    Andreas Stavropoulos
    Abstract Objectives: To evaluate the results of guided tissue regeneration (GTR) treatment of intrabony defects with bioresorbable membranes after 6,7 years, and to disclose factors that may influence the long-term outcome of the treatment. Methods: Twenty-five defects in 19 patients were treated by means of polylactic acid/citric acid ester copolymer bioresorbable membranes. At baseline and after 1 and 6,7 years, the following parameters were recorded: (1) probing pocket depth (PPD), (2) gingival recession (REC), (3) probing attachment level (PAL)=PPD+REC, (4) presence/absence of plaque (PI), (5) presence/absence of bleeding on probing (BOP). Smoking habits and frequency of dental-control visits were also recorded. Significance of differences between categorical variables was evaluated with McNemar's test, and between numerical variables with the t -test for paired observations. Generalized linear models were constructed to evaluate the influence of various factors on PAL gain and PPD changes from 1 to 6,7 years. Association of smoking, frequency of dental controls, oral hygiene, and BOP with sites losing 2 mm in PAL was evaluated with Fisher's exact test. Results: At baseline, a mean PPD of 8.7±1.1 mm and a mean PAL of 9.8±1.5 mm was recorded. Statistically significant clinical improvements were observed at 1 and 6,7 years after GTR treatment. An average residual PPD of 3.8±1.1 mm and a mean PAL gain of 3.8±1.4 mm were observed after 1 year. After 6,7 years the corresponding values were 4.7±1.3 and 3.6±1.4 mm, respectively. There were no statistically significant differences between the 1- and the 6,7-year values. At the 6,7-year control, only 16% of the sites had lost 2 mm (maximum 3 mm), of the PAL gain obtained 1 year after GTR treatment. None of the sites had lost all of the attachment gained 1 year after treatment. Smoking, frequency of dental controls, oral hygiene, and BOP did not seem to influence the change of PPD and PAL gain, or the stability of PAL gain (i.e. losing PAL or not) from 1 to 6,7 years from treatment. Conclusion: Clinical improvements achieved by GTR treatment of intrabony defects by means of bioresorbable membranes can be maintained on a long-term basis. [source]


    Influence of interleukin-1 gene polymorphism on periodontal regeneration in intrabony defects

    JOURNAL OF PERIODONTAL RESEARCH, Issue 1 2003
    M. Christgau
    The aim of this controlled retrospective study was to evaluate the influence of an IL-1 gene polymorphism on the clinical and radiographic healing outcomes of GTR therapy. The study included 47 adult periodontitis patients with 94 deep intrabony defects treated by GTR using different membrane materials. The following clinical parameters were recorded at baseline and 12 months after surgery: papillary bleeding index (PBI), gingival recession (REC), probing pocket depth (PPD), clinical attachment level (CAL), and the vertical relative attachment gain (V-rAG). Bone changes in the defect regions due to GTR therapy were quantitatively evaluated using digital subtraction radiography (DSR). Polymorphisms of the IL-1A gene at position ,,889 and of the IL-1B gene at position +,3953 were analyzed by PCR. Statistical analysis was performed using the Mann,Whitney-U and the Wilcoxon-Signed-Rank tests (, = 0.05). The study comprised 19 IL-1 genotype positive (IL-1 +) patients and 28 IL-1 genotype negative (IL-1 ,) patients. Twelve months after GTR therapy, both patient groups revealed statistically significant PPD reductions and CAL gain [median (25/75% percentiles)]: ,PPD [IL-1 + : 4.0 (2.5/5.0) mm; IL-1- : 3.8 (3.0/4.9) mm], ,CAL [IL-1 + : 3.5 (3.0/4.8) mm; IL-1 ,: 3.0 (1, 2/4, 5) mm]. V-rAG amounted to 60.0 (47.7/78.6)% in IL-1 + patients and 53.1 (43.4/81.9)% in IL-1 , patients. Both patient groups showed significant bone density gain in 40% (IL-1 +) and 43.6% (IL-1 ,) of the initial defect area due to GTR. Neither the clinical nor the radiographic healing parameters revealed any statistically significant differences in the GTR healing outcome between IL-1 + and IL-1 , patients. In conclusion, these 12-month findings indicate that the IL-1 gene polymorphism has no influence on the clinical and radiographic regeneration results following GTR therapy. [source]


    Saponaria officinalis karyology and karyotype by means of image analyzer and atomic force microscopy

    MICROSCOPY RESEARCH AND TECHNIQUE, Issue 10 2008
    S. Di Bucchianico
    Abstract The aim of this work was to offer a contribution to the characterization of taxonomic entity of Saponaria officinalis (2n = 28; an herbaceous perennial species; saporin, a type 1 Ribosome Inactivating Protein, is present in leaves and seeds) by a cytogenetic and karyomorphological approach. We investigated the karyotype's morphometry correlated with Stebbin's symmetric index; the same information has been used for computing the indices resemblance between chromosomes (REC), symmetric indices (SYI), and total form (TF%) which allow the comparison between species and evaluation of karyological evolution. Fluorescence intensities of the stained nuclei were measured by a flow cytometer and, for the first time, values for nuclear DNA content were estimated by comparing nuclei fluorescence intensities of the test population with those of appropriate internal DNA standards. Our study is also aimed to introduce chromosomal volumes, which were determined by atomic force microscopy (AFM), as novel karyomorphological parameter which could allow for chromosome discrimination especially when tiny ones are present. Microsc. Res. Tech., 2008. © 2008 Wiley-Liss, Inc. [source]


    Analysis of FimX, a phosphodiesterase that governs twitching motility in Pseudomonas aeruginosa

    MOLECULAR MICROBIOLOGY, Issue 4 2006
    Barbara I. Kazmierczak
    Summary Type IV pili (Tfp) are polar surface structures of Pseudomonas aeruginosa required for twitching motility, biofilm formation and adherence. One protein required for the assembly of tfp is FimX, which possesses both GGDEF and EAL domains characteristic of diguanylate cyclases and phosphodiesterases respectively. In this work we demonstrate that FimX has phosphodiesterase activity towards bis-(3,-5,)-cyclic dimeric guanosine monophosphate (c-di-GMP), but does not show diguanylate cyclase activity. Instead, the imperfect GGDEF domain of FimX likely serves to activate phosphodiesterase activity when bound to GTP, as has recently been described for the Caulobacter crescentus composite GGDEF-EAL protein, CC3396. Bacteria expressing FimX in which either the GGDEF or EAL domain is deleted or mutated have phenotypes indistinguishable from a ,fimX strain, demonstrating the importance of both domains to function. Previous work has shown that FimX localizes to the bacterial pole. In this work we show that restriction of FimX to a single pole requires intact GGDEF and EAL domains. Deletion of the amino-terminal REC domain of FimX, which contains a putative polar localization signal, results in a protein that still supports intermediate levels of pilus assembly and function. RFP,FimX,REC, unlike RFP,FimX, is no longer localized to the bacterial pole, while transmission electron microscopy shows that surface pili can originate from non-polar sites in this mutant. Although ,fimX mutants show limited in vitro cytotoxicity, they are as virulent as the wild-type strain in a murine model of acute pneumonia. [source]


    Effectiveness of the river environment classification in the Auckland Region

    NEW ZEALAND GEOGRAPHER, Issue 3 2008
    Liza Inglis
    Abstract:, The River Environment Classification (REC) provides a GIS-based tool to differentiate between biophysical attributes of river systems. This study tests the effectiveness of the REC as a tool to differentiate physical habitat and macroinvertebrate assemblages between four classes of stream in the Auckland region. Results indicate significant within-class variability in physical habitat and macroinvertebrate assemblages, with considerable overlap among the four classes. Biophysically meaningful stream classes cannot be identified from GIS-derived data applied in this research. Field analyses of physical habitat (i.e. geomorphic river condition) are required as a supplementary tool to interpret ecological relationships for differing stream types. [source]


    Rules for macroorganisms applied to microorganisms: patterns of endemism in benthic freshwater diatoms

    OIKOS, Issue 4 2007
    Cathy Kilroy
    Ecological theory based on the dynamic equilibrium model (DEM) suggests that maintenance of endemic taxa is most likely in stable, unproductive environments. We tested whether this hypothesis, which was developed mainly using terrestrial plant examples, held when applied to distributions of benthic freshwater diatoms in New Zealand. Given current arguments for the ubiquity of microbial organisms, with distributions determined mainly by environmental tolerances, demonstration that distinctive taxa with evidently restricted distributions conform to theory applicable to larger organisms would lend support to the opposite point of view, that barriers to dispersal do exist. We examined diatom communities from over 320 sites representing the entire spectrum of freshwater habitats in New Zealand and assessed relative abundances of the main taxa present. Each taxon distinguished was assigned to one of five distribution categories ranging from cosmopolitan to endemic. We derived indices of disturbance and productivity for each site using the River Environment Classification (REC), a GIS-based classification system developed for New Zealand rivers. Diatom taxa assigned to endemic or distinctive potential endemic categories were significantly more abundant in low disturbance sites but occurred across a range of productivities. However, bogs and tarns, both of which fell mainly into low disturbance and productivity classes, were distinctive in supporting relatively high proportions of endemic and potential endemic diatoms. Thus our findings in general conformed to the patterns predicted by the DEM, thereby supporting the role of dispersal limitation in diatoms. At the same time, conformity with the DEM helps to explain the continued coexistence in New Zealand freshwaters of many common and apparently cosmopolitan taxa with endemic diatoms, since the DEM explanation for maintenance of endemism does not rely on geographic isolation of species. [source]


    Prolonged strenuous exercise alters the cardiovascular response to dobutamine stimulation in male athletes

    THE JOURNAL OF PHYSIOLOGY, Issue 1 2005
    Robert C. Welsh
    Prolonged strenuous exercise has been associated with transient impairment in left ventricular (LV) systolic and diastolic function that has been termed ,cardiac fatigue'. It has been postulated that cardiac ,-adrenoreceptor desensitization may play a central role; however, data are limited. Accordingly, we assessed the cardiovascular response to progressive dobutamine stimulation after prolonged strenuous exercise (2 km swim, 90 km bike, 21 km run). Nine experienced male athletes were studied: PRE (2,3 days before), POST (after) and REC (1,2 days later). The cardiovascular response to progressive continuous dobutamine stimulation (0, 5, 20, and 40 ,g kg,1 min,1) was assessed, including heart rate (HR), systolic blood pressure (SBP), LV cavity areas (two-dimensional echocardiography) and contractility (end-systolic elastance, SBP/end-systolic cavity area (ESCA)). POST there was limited evidence of myocardial necrosis (measured by troponin I), while catecholamines were elevated. HR was higher POST (mean ±s.d.; PRE, 58 ± 9; POST, 79 ± 9; REC, 57 ± 7 beats min,1; P < 0.05), while SBP was lower (PRE, 127 ± 15; POST, 116 ± 9; REC, 121 ± 12 mmHg; P < 0.05). A blunted HR, SBP and LV contractility (SBP/ESCA; PRE 29 ± 6 versus POST 20 ± 6 mmHg cm,2; P < 0.05) response to dobutamine was demonstrated POST, with values returning towards baseline in REC. Following prolonged strenuous exercise, the chronotropic and inotropic response to dobutamine stimulation is blunted. This study supports the hypothesis that beta-receptor downregulation and/or desensitization may play a major role in prolonged-strenuous-exercise-mediated cardiac fatigue. [source]


    Enamel matrix derivative (Emdogain®) for periodontal tissue regeneration in intrabony defects

    AUSTRALIAN DENTAL JOURNAL, Issue 1 2010
    M Esposito
    Background:, Periodontitis is a chronic infective disease of the gums caused by bacteria present in dental plaque. This condition induces the breakdown of the tooth supporting apparatus until teeth are lost. Surgery may be indicated to arrest disease progression and regenerate lost tissues. Several surgical techniques have been developed to regenerate periodontal tissues including guided tissue regeneration (GTR), bone grafting (BG) and the use of enamel matrix derivative (EMD). EMD is an extract of enamel matrix and contains amelogenins of various molecular weights. Amelogenins are involved in the formation of enamel and periodontal attachment formation during tooth development. Objectives:, To test whether EMD is effective, and to compare EMD versus GTR, and various BG procedures for the treatment of intrabony defects. Search strategy:, We searched the Cochrane Oral Health Group Trials Register, CENTRAL, MEDLINE and EMBASE. Several journals were handsearched. No language restrictions were applied. Authors of randomized controlled trials (RCTs) identified, personal contacts and the manufacturer were contacted to identify unpublished trials. Most recent search: February 2009. Selection criteria:, RCTs on patients affected by periodontitis having intrabony defects of at least 3 mm treated with EMD compared with open flap debridement, GTR and various BG procedures with at least 1 year follow-up. The outcome measures considered were: tooth loss, changes in probing attachment levels (PAL), pocket depths (PPD), gingival recessions (REC), bone levels from the bottom of the defects on intraoral radiographs, aesthetics and adverse events. The following time-points were to be evaluated: 1, 5 and 10 years. Data collection and analysis:, Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted in duplicate and independently by two authors. Results were expressed as random-effects models using mean differences for continuous outcomes and risk ratios (RR) for dichotomous outcomes with 95% confidence intervals (CI). It was decided not to investigate heterogeneity, but a sensitivity analysis for the risk of bias of the trials was performed. Main results:, Thirteen trials were included out of 35 potentially eligible trials. No included trial presented data after 5 years of follow-up, therefore all data refer to the 1-year time point. A meta-analysis including nine trials showed that EMD treated sites displayed statistically significant PAL improvements (mean difference 1.1 mm, 95% CI 0.61 to 1.55) and PPD reduction (0.9 mm, 95% CI 0.44 to 1.31) when compared to placebo or control treated sites, though a high degree of heterogeneity was found. Significantly more sites had <2 mm PAL gain in the control group, with RR 0.53 (95% CI 0.34 to 0.82). Approximately nine patients needed to be treated (NNT) to have one patient gaining 2 mm or more PAL over the control group, based on a prevalence in the control group of 25%. No differences in tooth loss or aesthetic appearance as judged by the patients were observed. When evaluating only trials at a low risk of bias in a sensitivity analysis (four trials), the effect size for PAL was 0.62 mm (95% CI 0.28 to 0.96), which was less than 1.1 mm for the overall result. Comparing EMD with GTR (five trials), GTR showed statistically significant more postoperative complications (three trials, RR 0.12, 95% CI 0.02 to 0.85) and more REC (0.4 mm 95% CI 0.15 to 0.66). The only trial comparing EMD with a bioactive ceramic filler found statistically significant more REC (-1.60 mm, 95% CI ,2.74 to ,0.46) at the EMG treated sites. Authors' conclusions:, One year after its application, EMD significantly improved PAL levels (1.1 mm) and PPD reduction (0.9 mm) when compared to a placebo or control, however, the high degree of heterogeneity observed among trials suggests that results have to be interpreted with great caution. In addition, a sensitivity analysis indicated that the overall treatment effect might be overestimated. The actual clinical advantages of using EMD are unknown. With the exception of significantly more postoperative complications in the GTR group, there was no evidence of clinically important differences between GTR and EMD. Bone substitutes may be associated with less REC than EMD. Plain language summary:, Enamel matrix derivative (Emdogain®) for periodontal tissue regeneration in intrabony defects. Emdogain might have some advantages over other methods of regenerating the tissue supporting teeth lost by gum disease, such as less postoperative complications, but has not been shown to save more compromised teeth or that patients noticed any aesthetic improvement 1 year after its application. Bacteria in plaque can cause gum disease (periodontitis) that breaks down tissue supporting teeth. Surgical cleaning tries to stop the disease to save loose teeth. Bone grafting, guided tissue regeneration and enamel matrix derivatives (such as Emdogain) aim to regenerate support tissues. Emdogain contains proteins (derived from developing pig teeth) believed to regenerate tooth attachment. The review found that adjunctive application of Emdogain regenerates about 1 mm more tissue than surgical cleaning alone, although it is unclear to which extent such improvement is noticeable since patients did not find any difference in the aesthetic results. Emdogain showed similar clinical results to guided tissue regeneration, but is simpler to use and determines less complications. Bone substitutes may induce less gum retraction than Emdogain. No serious adverse reactions to Emdogain were reported in trials. [source]


    A Robust Genome-Wide Scan Statistic of the Wellcome Trust Case,Control Consortium

    BIOMETRICS, Issue 4 2009
    Jungnam Joo
    Summary In genome-wide association (GWA) studies, test statistics that are efficient and robust across various genetic models are preferable, particularly for studying multiple diseases in the Wellcome Trust Case,Control Consortium (WTCCC, 2007,,Nature,447, 661,678). A new test statistic, the minimum of the p-values of the trend test and Pearson's test, was considered by the WTCCC. It is referred to here as MIN2. Because the minimum of two p-values is no longer a valid p-value itself, the WTCCC only used it to rank single nucleotide polymorphisms (SNPs) but did not report the p-values of the associated SNPs when MIN2 was used for ranking. Given its importance in practice, we derive the asymptotic null distribution of MIN2, study some of its analytical properties related to GWA studies, and compare it with existing methods (the trend test, Pearson's test, MAX3, and the constrained likelihood ratio test [CLRT]) by simulations across a wide range of possible genetic models: the recessive (REC), additive (ADD), multiplicative (MUL), dominant (DOM), and overdominant models. The results show that MAX3 and CLRT have greater efficiency robustness than other tests when the REC, ADD/MUL, and DOM models are possible, whereas Pearson's test and MIN2 have greater efficiency robustness if the possible genetic models also include the overdominant model. We conclude that robust tests (MAX3, MIN2, CLRT, and Pearson's test) are preferable to a single trend test for initial GWA studies. The four robust tests are applied to more than 100 SNPs associated with 11 common diseases identified by the two WTCCC GWA studies. [source]


    Double-blind randomized controlled trial study on post-extraction immediately restored implants using the switching platform concept: soft tissue response.

    CLINICAL ORAL IMPLANTS RESEARCH, Issue 4 2009
    Preliminary report
    Abstract Aim: To evaluate the soft tissue response to immediately placed implants using the platform switching concept. Material and methods: In 22 patients, 22 implants of 5.5 mm platform diameter were placed immediately into fresh extraction sockets in maxillae without compromised bone tissue. Eventual post-extraction bone defects were filled using bovine bone matrix mixed with collagen. Immediately after insertion, implants were randomly divided: 11 implants were connected with a 3.8 mm diameter abutment (test group) and 11 with a 5.5 mm diameter abutment (control group). A provisional crown was adapted and adjusted for non-functional immediate positioning. Two months later, definitive prosthetic rehabilitation was performed. Periodontal parameter, buccal peri-implant mucosal changes (REC), mesial and distal papilla height (PH) and vertical height of jumping distance (VHG) were measured at the time of implant placement, of definitive prosthesis insertion and every 6 months thereafter. Results: The mean follow-up was 25 months. All implants were clinically osseointegrated. The test group showed a +0.18 mm REC gain. PH gain was +0.045 mm on average. The mean values were statistically significant (P,0.005) compared with the control group (PH=,0.88 mm; REC=,0.45 mm). No difference between the two groups in periodontal parameters was found. The mean value of bone filling was 7.51 mm in the test group (97.4% of VHG) and 8.57 mm in the control group (95.2% of VHG). No statistically significant difference was found between the two groups. Conclusions: This study suggests that, in a limited time period of 2 years, immediately placed implants with subsequent platform switching can provide peri-implant tissue stability. [source]


    Therapy of peri-implantitis with resective surgery

    CLINICAL ORAL IMPLANTS RESEARCH, Issue 1 2005
    A 3-year clinical trial on rough screw-shaped oral implants.
    Abstract: The purpose of this randomized clinical trial was to compare the clinical outcome of two different surgical approaches for the treatment of peri-implantitis. Seventeen patients with ITI® implants were included consecutively over a period of 5 years. The patients were randomized with a lottery assignment. Ten patients were treated with resective surgery and modification of surface topography (test group). The remaining seven patients were treated with resective surgery only (control group). Clinical parameters (suppuration, modified plaque index , mPI, modified bleeding index , mBI, probing pocket depth , PPD, pseudopocket , DIM, mucosal recession , REC, probing attachment level , PAL) were recorded at baseline, as well as 6, 12, 24 and 36 months after treatment. The cumulative survival rate for the implants of the test group was 100% after 3 years. After 24 months, two hollow-screw implants of control group were removed because of mobility. Consequently, the cumulative survival rate was 87.5%. The recession index in the control group was significantly lower than in the test group at 24 months (Student's t -value of ,2.14). On the contrary, control group showed higher PPD, PAL and mBI indexes than test group (Student's t -values of +5.5, +2.4 and +9.61, respectively). The PPD and mBI indexes for the implants of the control group were significantly higher at baseline than 24 months later (Student's t -values of +3.18 and +3.33, respectively). Recession and PAL indexes resulted in values significantly lower than baseline (Student's t -values of ,4.62 and ,2.77, respectively). For the implants of the test group PPD and mBI indexes were significantly higher at baseline than 36 months after (Student's t -values of +11.63 and +16.02, respectively). Recession index resulted in values significantly lower at baseline (Student's t -value of ,5.05). No statistically significant differences were found between PAL index measurement at baseline and 36 months later (Student's t -value of +0.89). In conclusion, resective therapy associated with implantoplasty seems to influence positively the survival of oral implants affected by inflammatory processes. Résumé Le but de cet essai clinique randomisé a été de comparer la guérison clinique de deux approches chirurgicales différentes pour le traitement de la paroïmplantite. Dix-sept patients avec des implants ITI® ont été inclus dans cette étude durant une période de cinq années. Les patients étaient répartis au hasard. Dix patients étaient traités avec une chirugie de résection et une modification de la topographie de surface (groupe test). Les derniers sept patients ont été traités avec la chirurgie de résection seulement (groupe contrôle). Des paramètres cliniques [suppuration, indice de plaque modifiée (mPI), indice de saignement modifié (mBI), profondeur de poche au sondage (PPD), pseudo poches (DIM), récession de la muqueuse (Rec), niveau d'attache au sondage (PAL)] ont été mesurés lors de l'examen initial et après six, douze, 24 et 36 mois. Le taux cumulatif pour les implants dans le groupe test était de 100% après trois années. Après 24 mois, deux implants vis creux du groupe contrôle ont été enlevés à cause de la mobilité. En conséquence, le taux de survie cumulatif était de 87,5%. L'indice de récession dans le groupe contrôle était significativement inférieur à celui du groupe test à 24 mois (valeur du test T de Student ,2,14). Par contre le groupe contrôle montrait des indices plus importants de PPD, PAL et mBI que le groupe test (valeurs du test T de Student respectivement de+5,50,+2,40,+9,61). Les indices PPD et mBI pour les implants du groupe contrôle étaient significativement plus importants lors de l'examen initial que 24 mois plus tard (valeurs du test T de Student respectivement de+ 3,18 et+3,33). Les indices de récession et de PAL résultaient en indices significativement inférieures que lors de l'examen initial (valeurs du test T de Student respectivement de ,4,62, ,2,77). Pour les implants du groupe test, les indices PPd et mBI étaient significativement plus importants lors de l'examen initial que 36 mois plus tard (valeurs du test T de Student respectivement de+11,63, 16,02). L'indice de récession résultait en indice significativement inférieur lors de l'examen initial (valeurs du test T de Student ,5,05). Aucune différence significative n'a été trouvée pour la mesure de l'indice PAL entre l'examen initial et 36 mois (valeur du test T de Student de+0,89). En conclusion, le traitement de résection associéà une plastieimplantaire semble influencer de manière positive la survie des implants dentaires affectés par les processus infectieux. Zusammenfassung Das Ziel dieser randomisierten klinischen Studie war, die klinischen Resultate von zwei verschiedenen chirurgischen Behandlungsvarianten der Periimplantitis zu vergleichen. Man nahm während einer Zeitdauer von fünf Jahren 17 Patienten mit ITI®-Implantaten fortlaufend in die Studie auf. Mit einem lotterieartigen System teilte man die Patienten zufällig auf. 10 der Patienten erhielten eine resektive Chirurgie und man modifizierte zusätzlich die Implantatoberfläche (Testgruppe). Bei den übrigen 7 wandte man ausschliesslich die resektive Chirurgie an (Kontrollgruppe). Zu Beginn sowie 6, 12, 24 und 36 Monate nach der Behandlung erhob man folgende klinischen Parameter: Eiterung, modifizierter Plaqueindex , mPI, modifizierter Blutungsindex , mBI, Sondierungstiefe , PPD, Pseudotaschen , DIM, Mukosarezession , Rec, sondierbares Attachmentniveau , PAL. Die kumulative Überlebensrate der Implantate in der Testgruppe betrug nach 3 Jahren 100%. Nach 24 Monaten mussten infolge Mobilität 2 Hohlschraubenimplantate der Kontrollgruppe entfernt werden. Daher betrug die kumulative Überlebensrate hier 87.5%. Der Rezessionsindex nach 24 Monaten war in der Kontrollgruppe signifikant tiefer als in der Testgruppe (T-Student Wert ,2.14). Dagegen zeigte die Kontrollgruppe höhere Indices bei der PPD, dem PAL und beim mBI als die Testgruppe (T-Student Werte von +5.5/+2.4 und +9.61). Die PPD und die mBI-Indices der Implantate aus der Kontrollgruppe waren zu Beginn signifikant höher als 24 Monate später (T-Student Werte von +3.18 und +3.33). Die Rezessions- und PAL-Indices waren dagegen signifikant tiefer als zu Beginn (T-Student Werte von ,4.62 und ,2.77). Bei den Implantaten der Testgruppe waren die PPD- und mBI-Indices zu Beginn signifikant höher als nach 36 Monaten (T-Student Werte von +11.63 und +16.02). Der Rezessionsindex war bei Studienbeginn signifikant tiefer (T-Student Wert von ,5.05). Bei den Messungen des PAL-Index konnte man zwischen den Anfangswerten und denjenigen nach 36 Monaten keine statistisch signifikanten Unterschiede erkennen (T-Student Wert von +0.89). Zusammenfassend kann man feststellen, dass eine resektive Therapie verbunden mit einer Oberflächenveränderung, die Überlebensrate der von einem entzündlichen Prozess betroffenen Implantate positiv zu beeinflussen vermag. Resumen El propósito de este estudio clínico aleatorio fue comparar los resultados clínicos de dos enfoques quirúrgicos diferentes para el tratamiento de periimplantitis. Se incluyeron a diecisiete pacientes consecutivos con implantes ITI® durante un periodo de cinco años. Los pacientes se asignaron aleatoriamente por medio de un sistema de lotería. Se trató a diez pacientes con cirugía resectiva y modificación de la topografía de superficie (grupo de prueba). Los siete pacientes restantes se trataron con cirugía resectiva solamente (grupo de control). Se recogieron parámetros clínicos (supuración, índice de placa modificado , mPI, índice de sangrado modificado , mBI, profundidad de sondaje de la bolsa , PPD, pseudobolsa , DIM, recesión mucosa , REC, nivel de inserción al sondaje , PAL) al inicio, al igual que a los 6, 12, 24 y 36 meses tras el tratamiento. El índice acumulativo de éxito del grupo de prueba tras 3 años fue del 100%. A los 24 meses se retiraron dos implantes huecos roscados del grupo de control debido a movilidad. Consecuentemente el índice acumulado de supervivencia fue del 87.5%. El índice de recesión en el grupo de control fue significativamente más bajo que en el grupo de prueba a los 24 meses (valor T-student de ,2.14). Por el contrario, el grupo de control mostró unos índices PPD, PAL y mBI mas altos que en el grupo de prueba (valores de T-student de +5.5 +2.4 y +9.61 respectivamente). Los índices PPD y mBI para los implantes del grupo de control fueron significativamente mas altos al inicio que 24 meses mas tarde (valores de T-student de +3.18 y +3.33 respectivamente). Los índices de recesión y PAL resultaron significativamente mas bajos que al inicio (valores de T-student de ,4.62 y ,2.77 respectivamente). Para los implantes del grupo de prueba los índices PPD y mBI fueron significativamente mas altos al inicio que tras 36 meses (valores de T-student de +11.63 y +16.02 respectivamente). El índice de recesión resultó ser significativamente más bajo al inicio (valores de T-student de ,5.05). No se encontraron diferencias estadísticamente significativas para las mediciones de índice de PAL al inicio y 36 meses mas tarde (valores de T-student de +0.89). En conclusión, la terapia resectiva asociada con implantoplastia parece influir positivamente sobre la supervivencia de los implantes orales afectados por procesos inflamatorios. [source]


    Ultra-incompressible and hard technetium carbide and rhenium carbide: First-principles prediction

    PHYSICA STATUS SOLIDI - RAPID RESEARCH LETTERS, Issue 3 2008
    Yuan Xu Wang
    Abstract Using density functional theory, the author predicts that the compounds ReC and TcC with the hexagonal WC-like structure are ultra-incompressible and hard materials. This is concluded from the very large bulk and shear moduli. The phonon dispersion reveals no soft modes indicating the stability of the two materials. The calculated density of states shows that ReC and TcC are metallic. The structural and elastic properties of OsC, IrC, and PtC with hexagonal and cubic structure are also investigated for comparison. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


    ROCK inhibitor (Y27632) increases apoptosis and disrupts the actin cortical mat in embryonic avian corneal epithelium

    DEVELOPMENTAL DYNAMICS, Issue 3 2004
    Kathy K.H. Svoboda
    Abstract The embryonic chicken corneal epithelium is a unique tissue that has been used as an in vitro epithelial sheet organ culture model for over 30 years (Hay and Revel [1969] Fine structure of the developing Avian cornea. Basel, Switzerland: S. Karger A.G.). This tissue was used to establish that epithelial cells could produce extracellular matrix (ECM) proteins such as collagen and proteoglycans (Dodson and Hay [1971] Exp Cell Res 65:215,220; Meier and Hay [1973] Dev Biol 35:318,331; Linsenmayer et al. [1977] Proc Natl Acad Sci U S A 74:39,43; Hendrix et al. [1982] Invest Ophthalmol Vis Sci 22:359,375). This historic model was also used to establish that ECM proteins could stimulate actin reorganization and increase collagen synthesis (Sugrue and Hay [1981] J Cell Biol 91:45,54; Sugrue and Hay [1982] Dev Biol 92:97,106; Sugrue and Hay [1986] J Cell Biol 102:1907,1916). Our laboratory has used the model to establish the signal transduction pathways involved in ECM-stimulated actin reorganization (Svoboda et al. [1999] Anat Rec 254:348,359; Chu et al. [2000] Invest Ophthalmol Vis Sci 41:3374,3382; Reenstra et al. [2002] Invest Ophthalmol Vis Sci 43:3181,3189). The goal of the current study was to investigate the role of ECM in epithelial cell survival and the role of Rho-associated kinase (p160 ROCK, ROCK-1, ROCK-2, referred to as ROCK), in ECM and lysophosphatidic acid (LPA) -mediated actin reorganization. Whole sheets of avian embryonic corneal epithelium were cultured in the presence of the ROCK inhibitor, Y27632 at 0, 0.03, 0.3, 3, or 10 ,M before stimulating the cells with either collagen (COL) or LPA. Apoptosis was assessed by Caspase-3 activity assays and visualized with annexin V binding. The ROCK inhibitor blocked actin cortical mat reformation and disrupted the basal cell lateral membranes in a dose-dependent manner and increased the apoptosis marker annexin V. In addition, an in vitro caspase-3 activity assay was used to determine that caspase-3 activity was higher in epithelia treated with 10 ,M Y-27632 than in those isolated without the basal lamina or epithelia stimulated with fibronectin, COL, or LPA. In conclusion, ECM molecules decreased apoptosis markers and inhibiting the ROCK pathway blocked ECM stimulated actin cortical mat reformation and increased apoptosis in embryonic corneal epithelial cells. Developmental Dynamics 229:579,590, 2004. © 2004 Wiley-Liss, Inc. [source]


    Analysis of the glucocerebrosidase gene and mutation profile in 144 Italian gaucher patients,,

    HUMAN MUTATION, Issue 3 2002
    Mirella Filocamo
    Abstract Gaucher disease (GD), the most prevalent lysosomal storage disease characterized by a remarkable degree of clinical variability, results from deleterious mutations in the glucocerebrosidase gene (GBA). In this paper we report the molecular characterization of 144 unrelated Italian GD patients with the three types of the disease. The allelic frequencies of Italians are reported and the mutation profile is analyzed. Besides the common N370S, L444P, RecNciI, G202R, IVS2+1G>A, D409H, F213I mutations, the different molecular strategies, used for the mutation detection, identified the rare N107L, R131C, R170C, R170P, N188S, S196P, R285C, R285H, W312C, D399N, A446P, IVS10-1G>A, Rec,55, total gene deletion, as well as 12 mutant alleles that were exclusively present in the Italian population until now: the previously reported R353G, N370S+S488P mosaicism, IVS8(-11delC)-14T>A), Rec I, Y418C, and the seven novel alleles D127X, P159T, V214X, T231R, L354X, H451R, and G202R+M361I. The wide phenotypic differences observed within the genotypic groups as well as between siblings implicate a significant contribution of other modifying genetic and/or non-genetic factors and claim a comprehensive valuation of the patient including clinical., biochemical and molecular investigations for prognosis, appropriate interventive therapy and reliable genetic counseling. © 2002 Wiley-Liss, Inc. [source]


    Characterization of Taylor vortex flow in a short liquid column

    AICHE JOURNAL, Issue 12 2009
    Rensheng Deng
    Abstract We present a study on Taylor vortex flow in the annulus between a rotating inner cylinder and a stationary outer cylinder, featured with a wide gap (radius ratio is 0.613) and a short column (aspect ratio is 5.17). A particle image velocimetry (PIV) system was used to determine the position, shape, and velocity distribution of the vortices, by which the flow was also confirmed to lie in the nonwavy Taylor vortex regime for all operating conditions explored in this study. Our results suggest that end boundary effects are important, in which the vortex number decreases with decreasing column length. For a system with an aspect ratio of 5.17, six vortices appear in the gap with their position, size, and shape varying at different Reynolds numbers. The fluid velocities show an asymmetric feature with respect to the vortex centers, while the maximum axial and radial velocities increase almost linearly with the increasing reduced Reynolds number (Re , Rec). In addition, computational fluid dynamics study was employed under the same conditions, and its results agree well with the PIV measurements. Overall, this study provides a quantitative understanding of the formation of Taylor vortices in a constrained space. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source]


    Lymphatic/Blood Endothelial Cell Connections at the Capillary Level in Adult Rat Mesentery

    THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 10 2010
    Jennifer L. Robichaux
    Abstract Analyses of microvascular networks with traditional tracer filling techniques suggest that the blood and lymphatic systems are distinct without direct communications, yet involvement of common growth factors during angiogenesis and lymphangiogenesis suggest that interactions at the capillary level are possible. To investigate the structural basis for lymphatic/blood endothelial cell connections during normal physiological growth, the objective of this study was to characterize the spatial relations between lymphatic and blood capillaries in adult rat mesenteric tissue. Using immunohistochemical methods, adult male Wistar rat mesenteric tissues were labeled with antibodies against PECAM (an endothelial marker) and LYVE-1, Prox-1, or Podoplanin (lymphatic endothelial markers) or NG2 (a pericyte marker). Positive PECAM labeling identified apparent lymphatic/blood endothelial cell connections at the capillary level characterized by direct contact or direct alignment with one another. In PECAM labeled networks, a subset of the lymphatic and blood capillary blind ends were connected with each other. Intravital imaging of FITC-Albumin injected through the femoral vein did not identify lymphatic vessels. At contact sites, lymphatic endothelial markers did not extend along blood capillary segments. However, PECAM positive lymphatic sprouts, structurally similar to blood capillary sprouts, lacked observable lymphatic marker labeling. These observations suggest that nonlumenal lymphatic/blood endothelial cell interactions exist in unstimulated adult microvascular networks and highlight the potential for lymphatic/blood endothelial cell plasticity. Anat Rec 293:1629,1638, 2010. © 2010 Wiley-Liss, Inc. [source]


    Developmental Changes of Cell Adhesion Molecule Expression in the Fetal Mouse Liver

    THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 10 2010
    Yoshinori Sugiyama
    Abstract Developmental changes of cell adhesion molecule expression, especially in nonparenchymal cells, have hardly ever been analyzed in the murine liver. The present study was undertaken to immunohistochemically examine the expression of NCAM, ICAM, VCAM, and N-cadherin during mouse liver development and in fetal liver cell cultures. NCAM was transiently expressed in mesenchymal cells of the septum transversum and sinusoidal cells in liver development. In vitro studies demonstrated that desmin-positive stellate cells expressed this cell adhesion molecule. NCAM expression in periportal biliary epithelial cells and connective tissue cells also coincided well with bile duct remodeling processes in the perinatal periods. Expression of ICAM and VCAM was transiently restricted to hepatoblasts, hepatocytes and hemopoietic cells in fetal stages. N-cadherin was expressed not only in hepatoblasts and hepatocytes, but also in nonparenchymal cells such as endothelial cells, stellate cells and connective tissue cells, however the expression was weak. These results suggest that each cell adhesion molecule may play an important role during development in hepatic histogenesis, including hepatoblast/hepatocyte-stellate cell interactions, hemopoiesis, and bile duct morphogenesis. Anat Rec 293:1698,1710, 2010. © 2010 Wiley-Liss, Inc. [source]


    Stochastic Morphometric Model of the Balb/c Mouse Lung

    THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 10 2010
    Pierre Madl
    Abstract The laboratory mouse is often used as a human surrogate in aerosol inhalation studies. Morphometric data on the tracheobronchial geometry of three in situ lung casts of the Balb/c mouse lung produced by the Air Pollution Health Effects Laboratory were analyzed in terms of probability density functions and correlations among the different airway parameters. The results of this statistical analysis reveal significant differences in diameters and branching angles between major and minor progeny branching off from the same parent airway at a given airway bifurcation. Number of bronchial airways generations along a given path, expressed by the termination probability, branching angles, and daughter-to-parent diameter ratios indicate that the location of an airway with defined linear airway dimensions within the lung is more appropriately identified by its diameter (or its parent diameter) than by an assigned generation number. We, therefore, recommend classifying the mouse lung airways by their diameters and not by generation numbers, consistent with our previous analysis of the rather monopodial structure of the rat lung (Koblinger et al., J Aerosol Med 1995;8:7,19; Koblinger and Hofmann, J Aerosol Med 1995;8:21,32). Because of lack of corresponding information on respiratory airways, a partly stochastic symmetric acinar airway model was attached to the tracheobronchial model, in which the number of acinar airways along a given path was randomly selected from a measured acinar volume distribution. The computed distributions of the geometric airway parameters and their correlations will be used for random pathway selection of inhaled particles in subsequent Monte Carlo deposition calculations. Anat Rec 293:1766,1786, 2010. © 2010 Wiley-Liss, Inc. [source]


    The Pleural Curtain of the Camel (Camelus dromedarius)

    THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 10 2010
    Gerald R. Buzzell
    Abstract The visceral pleura of the camel (Camelus dromedarius) possesses a fibrous curtain of pleural threads or extensions along its basal margins, which extends into the pleural cavity of the costophrenic recesses. These threads are lined by mesothelium and have a core or stroma, which is largely collagenous. Small threads are avascular and nearly acellular. In larger proximal threads, blood vessels in the stroma are often arranged in a branching network, with irregular endothelia surrounded by several incomplete basal laminae. Lymphocytes and other inflammatory cell types aggregate in the stroma near blood vessels. The threads are lined by typical mesothelium except in patches close to the main pleural surface. These patches consist of layers of loosely applied cells with numerous cellular processes and features suggestive of phagocytosis. The position of the pleural curtain in the costophrenic recess and the presence of possibly phagocytotic cells suggest that the pleural curtain stirs, samples, and cleans the pleural fluid. The pleural curtain appears to be a feature of camelids and has also been seen in giraffes. Anat Rec 293:1776,1786, 2010. © 2010 Wiley-Liss, Inc. [source]


    The Cytoskeletal Regulator Zyxin is Required for Viability in Drosophila melanogaster

    THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 9 2010
    Patricia J. Renfranz
    Abstract The zyxin family of proteins function as cytoskeletal regulators in adhesion, actin assembly, and cell motility. Though fibroblasts derived from zyxin-null mice show striking defects in motility and response to mechanical stimuli, the mice are viable and fertile. In Drosophila melanogaster, the family is represented by a single homologue, Zyx102. To study the role of zyxin during development, we generated a zyx102 RNA-interference transgenic line that allows for the conditional knockdown of Zyx102. When UAST-zyx102-dsRNAi expression is driven broadly by Actin5C-GAL4, loss of Zyx102 results in lethality during the pharate adult stage, a narrow developmental window during which the fly must molt, resorb molting fluid, fill adult trachea with air, and execute a behavioral program to eclose. Zyx102 knockdown animals attempt to emerge, but their adult trachea do not fill with air. If dissected from the pupal case, knockdown individuals appear morphologically normal, but remain inviable. Anat Rec 293:1455,1469, 2010. © 2010 Wiley-Liss, Inc. [source]


    Development of the Tarsometatarsal Skeleton by the Lateral Fusion of Three Cylindrical Periosteal Bones in the Chick Embryo (Gallus gallus)

    THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 9 2010
    Yuichi Namba
    Abstract An avian tarsometatarsal (TMT) skeleton spanning from the base of toes to the intertarsal joint is a compound bone developed by elongation and lateral fusion of three cylindrical periosteal bones. Ontogenetic development of the TMT skeleton is likely to recapitulate the changes occurred during evolution but so far has received less attention. In this study, its development has been examined morphologically and histologically in the chick, Gallus gallus. Three metatarsal cartilage rods radiating distally earlier in development became aligned parallel to each other by embryonic day 8 (ED8). Calcification initiated at ED8 in the midshaft of cartilage propagated cylindrically along its surface. Coordinated radial growth by fabricating bony struts and trabeculae resulted in the formation of three independent bone cylinders, which further became closely apposed with each other by ED13 when the periosteum began to fuse in a back-to-back orientation. Bone microstructure, especially orientation of intertrabecular channels in which blood vasculature resides, appeared related to the observed rapid longitudinal growth. Differential radial growth was considered to delineate eventual surface configurations of a compound TMT bone, but its morphogenesis preceded the fusion of bone cylinders. Bony trabeculae connecting adjacent cylinders emerged first at ED17 in the dorsal and ventral quarters of intervening tissue at the mid-diaphyseal level. Posthatch TMT skeleton had a seemingly uniform mid-diaphysis, although the septa persisted between original marrow cavities. These findings provide morphological and histological bases for further cellular and molecular studies on this developmental process. Anat Rec 293:1527,1535, 2010. © 2010 Wiley-Liss, Inc. [source]


    Variations in the Thickness and Composition of the Skin of the Giraffe

    THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 9 2010
    Farzana Sathar
    Abstract This study examined the skin of two 1- to 2-year-old male giraffes and one adult male, determining skin thickness and histological structure with reference to it functioning as a component of the features required for the maintenance of blood pressure, dermal armor, or thermoregulation. It has been argued that a tight skin surrounding the extremities of the giraffe aids in the movement of fluid against gravity, hence preventing pooling of blood and tissue fluid (edema), but the skin has also been implicated in the thermoregulatory capacities and defensive anatomy of many mammalian species. In one of the younger giraffes, one-half of the skin was analyzed from which close to 170 sites were measured. In the other young and adult giraffes, spot tests to confirm the pattern observed in the fully analyzed individual were undertaken. It was discovered that the skin varied in thickness across the entire body and within regions of the body. Histological evaluation revealed that the skin was mostly collagenous, although interesting patterns of elastic fiber densities were also apparent. The skin in the neck and legs exhibited a morphology that may assist in cardiovascular regulation of blood flow to and from the head and legs, and the skin of the trunk and anterior neck has the possibility of functioning in a protective role. The analyses performed could not add any new data regarding the thermoregulatory role already described for giraffe skin. Anat Rec 293:1615,1627, 2010. © 2010 Wiley-Liss, Inc. [source]


    Disease Stage Characterization of Hepatorenal Fibrocystic Pathology in the PCK Rat Model of ARPKD

    THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 8 2010
    Stephen B. Mason
    Abstract The rat Pck gene is orthologous to the human PKHD1 gene responsible for autosomal recessive polycystic kidney disease (ARPKD). Both renal and hepatic fibrocystic pathology occur in ARPKD. Affected humans have a variable rate of progression, from morbidly affected infants to those surviving into adulthood. This study evaluated the PCK rat, a model of slowly progressive ARPKD. This model originated in Japan and was rederived to be offered commercially by Charles River Laboratories (Wilmington, MA). Previous studies have described the basic aspects of PCK pathology from privately held colonies. This study provides a comprehensive characterization of rats from those commercially available. Rats were bred, maintained on a 12:12 hr light/dark cycle, fed (7002 Teklad), and water provided ad libitum. Male and female rats were evaluated from 4 through 35 weeks of age with histology and serum chemistry. As the hepatorenal fibrocystic disease progressed beyond 18 weeks, the renal pathology (kidney weight, total cyst volume) and renal dysfunction (BUN and serum creatinine) tended to be more severe in males, whereas liver pathology (liver weight as % of body weight and hepatic fibrocystic volume) tended to be more severe in females. Hyperlipidemia was evident in both genders after 18 weeks. Bile secretion was increased in PCK rats compared with age-matched Sprague Dawley rats. The PCK is an increasingly used orthologous rodent model of human ARPKD. This characterization study of hepatorenal fibrocystic pathology in PCK rats should help researchers select stages of pathology to study and/or monitor disease progression during their longitudinal studies. Anat Rec 293:1279,1288, 2010. © 2010 Wiley-Liss, Inc. [source]


    Quantifying Mental Foramen Position in Extant Hominoids and Australopithecus: Implications for its Use in Studies of Human Evolution

    THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 8 2010
    Chris A. Robinson
    Abstract The location of the mental foramen on the mandibular corpus has figured prominently in debates concerning the taxonomy of fossil hominins and Gorilla gorilla. In this study we quantify the antero/posterior (A/P) position of the mental foramen across great apes, modern humans and Australopithecus. Contrary to most qualitative assessments, we find significant differences between some extant hominoid species in mental foramen A/P position supporting its potential usefulness as a character for taxonomic and phylogenetic analyses of fossil hominoids. Gorilla gorilla, particularly the eastern subspecies, with a comparatively longer dental arcade and fossil and extant hominins with reduced canines and incisors tend to exhibit more anteriorly positioned mental foramina. Conversely, Pan troglodytes exhibits more posteriorly positioned mental foramina. Variation in this character among Gorilla gorilla subspecies supports recent taxonomic assessments that separate eastern and western populations. In all taxa other than Pan troglodytes the A/P position of the mental foramen is positively allometric with respect to dental arcade length. Thus, within each of these species, specimens with longer dental arcades tend to have more posteriorly positioned mental foramina. Those species with greater sexual dimorphism in canine size and dental arcade length (i.e., Gorilla gorilla and Pongo pygmaeus) exhibit more extreme differences between smaller and larger individuals. Moreover, among great apes those individuals with greater anterior convergence of the dental arcade tend to exhibit more posteriorly positioned mental foramina. Dental arcade length, canine crown area and anterior convergence are all significantly associated with mental foramen A/P position, suggesting that these traits may influence taxonomic variation in the A/P position of the mental foramen. Anat Rec 293:1337,1349, 2010. © 2010 Wiley-Liss, Inc. [source]


    Microanatomy of the Mandibular Symphysis in Lizards: Patterns in Fiber Orientation and Meckel's Cartilage and Their Significance in Cranial Evolution

    THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 8 2010
    Casey M. Holliday
    Abstract Although the mandibular symphysis is a functionally and evolutionarily important feature of the vertebrate skull, little is known about the soft-tissue morphology of the joint in squamate reptiles. Lizards evolved a diversity of skull shapes and feeding behaviors, thus it is expected that the morphology of the symphysis will correspond with functional patterns. Here, we present new histological data illustrating the morphology of the joint in a number of taxa including iguanians, geckos, scincomorphs, lacertoids, and anguimorphs. The symphyses of all taxa exhibit dorsal and ventral fibrous portions of the joints that possess an array of parallel and woven collagen fibers. The middle and ventral portions of the joints are complemented by contributions of Meckel's cartilage. Kinetic taxa have more loosely built symphyses with large domains of parallel-oriented fibers whereas hard biting and akinetic taxa have symphyses primarily composed of dense, woven fibers. Whereas most taxa maintain unfused Meckel's cartilages, iguanians, and geckos independently evolved fused Meckel's cartilages; however, the joint's morphologies suggest different developmental mechanisms. Fused Meckel's cartilages may be associated with the apomorphic lingual behaviors exhibited by iguanians (tongue translation) and geckos (drinking). These morphological data shed new light on the functional, developmental, and evolutionary patterns displayed by the heads of lizards. Anat Rec 293:1350,1359, 2010. © 2010 Wiley-Liss, Inc. [source]


    Temporal and Spatial Distribution of the Cannabinoid Receptors (CB1, CB2) and Fatty Acid Amide Hydroxylase in the Rat Ovary

    THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 8 2010
    P. Bagavandoss
    Abstract Although the effects of ,9 -tetrahydrocannabinol (THC) on ovarian physiology have been known for many decades, its mechanism of action in the rat ovary remains poorly understood. The effects of THC and endocannabinoids on many cell types appear to be mediated through the G-protein-coupled CB1 and CB2 receptors. Evidence also suggests that the concentration of the endocannabinoid anandamide is regulated by cellular fatty acid amide hydrolase (FAAH). Therefore, we examined the rat ovary for the presence of CB1 and CB2 receptors and FAAH. The CB1 receptor was present in the ovarian surface epithelium (OSE), the granulosa cells of antral follicles, and the luteal cells of functional corpus luteum (CL). The granulosa cells of small preantral follicles, however, did not express the CB1 receptor. Western analysis also demonstrated the presence of a CB1 receptor. In both preantral and antral follicles, the CB2 receptor was detected only in the oocytes. In the functional CL, the CB2 receptor was detected in the luteal cells. FAAH was codistributed with CB2 receptor in both oocytes and luteal cells. FAAH was also present in the OSE, subepithelial cords of the tunica albuginea (TA) below the OSE, and in cells adjacent to developing preantral follicles. Western analysis also demonstrated the presence of FAAH in oocytes of both preantral and antral follicles. Our observations provide potential explanation for the effects of THC on steroidogenesis in the rat ovary observed by earlier investigators and a role for FAAH in the regulation of ovarian anandamide. Anat Rec 293:1425,1432, 2010. © 2010 Wiley-Liss, Inc. [source]


    Analysis of Cardiac Development in the Turtle Emys orbicularis (Testudines: Emidydae) using 3-D Computer Modeling from Histological Sections

    THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 7 2010
    Laura M.F. Bertens
    Abstract In this article we present a 3-D modeling study of cardiac development in the European pond turtle, Emys orbicularis (of the reptilian order Testudines). The study is aimed at elucidating the embryonic development of the horizontal septum in the ventricle and underscoring the importance of 3-D reconstructions in studying morphogenesis. Turtles possess one common ventricle, partly divided into three cava by a vertical and a horizontal septum, of which the embryonic origins have so far not been described. We used serial sectioning and computerized high-resolution 3-D reconstructions of different developmental stages to create a chronological overview of cardiogenesis, in order to study this process. This has yielded a new understanding of the development of the horizontal septum and (directly related) the looping of the heart tube. This looping is found to be markedly different from that in the human heart, with the turtle having two clear bends in the part of the heart tube leaving the primitive ventricle, as opposed to one in humans. It is this particular looping that is reponsible for the formation of the horizontal septum. In addition to our findings on the ventricular septation this study has also yielded new insights into the developmental origins of the pulmonary vein. The 3-D reconstructions were built using our platform TDR-3-D base and enabled us to study the developmental processes in specific parts of the turtle heart separately and in three dimensions, over time. The complete 3-D reconstructions have been made available to the reader via internet using our 3-D model browser application, which allows interactive viewing of the models. The browser application can be found on bio-imaging.liacs.nl/galleries/emysorbicularis/TurtleGallery.html, along with additional images of both models and histological sections and animation sequences of the models. By allowing the reader to view the material in such an interactive way, we hope to make optimal use of the new 3-D reconstruction techniques and to engage the reader in a more direct manner. Anat Rec 239:1101,1114, 2010. © 2010 Wiley-Liss, Inc. [source]


    The Anatomy of the Gastrointestinal Tract of the African Lungfish, Protopterus annectens

    THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 7 2010
    José M. Icardo
    Abstract The gastrointestinal tract of the African lungfish Protopterus annectens is a composite, which includes the gut, the spleen, and the pancreas. The gut is formed by a short oesophagus, a longitudinal stomach, a pyloric valve, a spiraling intestine, and a cloaca. Coiling of the intestine begins dorsally below the pylorus, winding down to form six complete turns before ending into the cloaca. A reticular tissue of undisclosed nature accompanies the winding of the intestinal mucosa. The spleen is located along the right side of the stomach, overlapping the cranial end of the pancreas. The pancreas occupies the shallow area, which indicates on the gut dorsal side the beginning of the intestine coiling. In addition, up to 25 lymphatic-like nodes accompany the inner border of the spiral valve. The mesenteric artery forms a long axis for the intestine. All the components of the gastrointestinal tract are attached to each other by connective sheaths, and are wrapped by connective tissue, and by the serosa externally. We believe that several previous observations have been misinterpreted and that the anatomy of the lungfish gut is more similar among all the three lungfish genera than previously thought. Curiously, the gross anatomical organization is not modified during aestivation. We hypothesize that the absence of function is accompanied by structural modifications of the epithelium, and are currently investigating this possibility. Anat Rec 293:1146,1154, 2010. © 2010 Wiley-Liss, Inc. [source]


    Onset of Apoptosis in the Cystic Duct During Metamorphosis of a Japanese Lamprey, Lethenteron reissneri

    THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 7 2010
    Mayako Morii
    Abstract A nonparasitic lamprey in Japan, Lethenteron reissneri, stops feeding prior to the commencement of metamorphosis. Resumption of feeding cannot take place due to major alterations in the digestive system, including loss of the gall bladder (GB) and biliary tree in the liver. This degeneration of bile ducts is considered to depend on programmed cell death or apoptosis, but molecular evidence of apoptosis remains lacking. Using terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining and immunohistochemistry with an antibody against active caspase-3, we showed that epithelial cells of the cystic duct (CD) and GB became TUNEL-positive by the early metamorphosing stage. Immunohistochemical staining of active caspase-3, a key mediator in the apoptotic cascade, showed that the apoptotic signal was initiated in the region around the CD in the late larval phase. In later stages, active caspase-3-positive epithelial cells were also observed in the large intrahepatic bile duct (IHBD) and peripheral small IHBDs. At the early metamorphosing stage, bile canaliculi between hepatocytes were dilated and displayed features resembling canaliculi in cholestasis. Onset of apoptosis around the CD, which is the pathway for the storage of bile juice, and progression of apoptosis towards the large IHBD, which is the pathway for the secretion of bile juice, may lead to temporary intrahepatic cholestasis. The present study represents the first precise spatial and temporal analysis of apoptosis in epithelial cells of the biliary tract system during metamorphosis of any lamprey species. Anat Rec 293:1155,1166, 2010. © 2010 Wiley-Liss, Inc. [source]