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Second Group (second + group)
Selected AbstractsHypothermic insult to the periodontium: a model for the study of aseptic tooth resorptionDENTAL TRAUMATOLOGY, Issue 1 2000C. W. Dreyer Abstract , The aim of the current investigation was to define an animal model for the study of hard tissue resorption by examining the responses of the periodontal ligament (PDL) to both single and multiple episodes of hypothermic injury to the crowns of rat teeth. A group of 12 male rats weighing 200,250 g were anesthetized, and pellets of dry ice (CO2) were applied once to the crowns of the right first maxillary molars for continuous periods of 10 or 20 min. Animals were sacrificed at 2, 7, 14 and 28 days and tissues were processed for routine histological examination. A second group of eight animals and a third group of 12 animals were subjected to three applications of dry ice over a period of 1 week and sacrificed at 2 and 14 days respectively after the final application. In addition to thermal insult, the periodontium of teeth from a fourth group of six rats was subjected to mechanical trauma. Examination of the sections from the group undergoing a single freezing episode revealed that, by 1 week, shallow resorption lacunae had appeared on the root surface. These became more extensive after 14 days. At the same time hyaline degeneration was evident in the PDL. Within this group, teeth subjected to the longer 20-min application times generally showed more extensive injuries. By 28 days, evidence of repair was observed with reparative cementum beginning to line the resorption lacunae in the root dentin. Sections from animals subjected to multiple episodes of thermal trauma and those subjected to additional mechanical insult showed more extensive external root resorption than those from single-injury animals. It was concluded that low temperature stimuli applied to the crowns of rat molars were capable of eliciting a sterile degenerative response in the PDL which, in turn, resulted in external root resorption. Furthermore, the degree of this tissue injury was commensurate with the duration and number of exposures to the trauma. The results also indicated that progression of the resorptive process required periodic exposure to the injury, in the absence of which repair to the damaged root occurred. [source] Sodium Hydroxide Chemical Matricectomy for the Treatment of Ingrown Toenails: Comparison of Three Different Application PeriodsDERMATOLOGIC SURGERY, Issue 7 2005Pelin Kocyigit MD Objective Sodium hydroxide matricectomy is a successful method for the treatment of ingrown toenails. This study was designed to evaluate the optimal sodium hydroxide application period providing high success rates with minimal postoperative morbidity. Materials and Methods Sixty-six patients with 225 ingrown nail edges were treated in three groups receiving 30-second, 1-minute, and 2-minute applications of sodium hydroxide. Each patient was reviewed postoperatively for pain, drainage, and tissue damage. The median long-term follow-up period was 14 months. Results The success rate of the therapy was 70.9% in the first group, 92.7% in the second group, and 94.4% in the third group. In all groups, about half of the patients experienced minimal pain within 48 hours following the operation, but only in the third group, 20% of the patients had minimal pain, which continued about 1 week. Drainage and tissue damage were minimal or mild in all groups and disappeared within 3 weeks in the first and second groups but were prolonged to 6 weeks in the third group. conclusion The success rate of 30-second application is significantly lower than 1-minute and 2-minute applications. Although the success rates of the latter two procedures are similar, the prolonged healing time is the disadvantage of the 2-minute application. We conclude that 1-minute application of 10% sodium hydroxide is simple, safe, and highly effective for the treatment of ingrown nails. [source] Use of Honey as an Adjunct in the Healing of Split-Thickness Skin Graft Donor SiteDERMATOLOGIC SURGERY, Issue 2 2003Aykut Misirlioglu MD BACKGROUND Different techniques are being used in treatment of split-thickness skin graft donor sites; however, there is not a widely accepted method established for these partial-thickness wounds. It is well known that honey has been very effective in the treatment of various types of wounds, but there is not any information about the usage of honey as split-thickness skin graft donor site dressing in the literature. OBJECTIVE To evaluate and compare the effectiveness of honey-impregnated gauzes, hydrocolloid dressings, and as a conventional dressing, saline-soaked gauzes for skin graft donor sites. METHODS This is a nonrandomized, prospective, open-label (noncontrolled), side-by-side comparison trial of various options that are available for second-intention healing of donor site for split-thickness skin grafts. Eighty-eight patients who underwent skin grafting were observed using two different groups. In the first group, the donor site was divided into two equal halves, with each half being treated with honey-soaked gauzes and the other half with paraffin gauzes (group 1A), hydrocolloid dressings (group 1B), and saline-soaked gauzes (group 1C) alternatively. In the second group, two separate donor sites were formed, with one of them being treated with honey-impregnated gauzes (groups 2A,C) and the other one treated with either paraffin gauzes (group 2A), hydrocolloid dressings (group 2B), or saline-soaked gauzes (group 2C). The healing time, rate of infection, and sense of pain were evaluated. RESULTS In the treatment of split-thickness skin graft donor sites, honey-impregnated gauzes showed faster epithelization time and a low sense of pain than paraffin gauzes and saline-soaked gauzes. There was no significant difference between honey-impregnated gauzes and hydrocolloid dressings with regard to epithelization time and sense of pain. CONCLUSION The use of honey-impregnated gauzes is effective, safe, and practical. Honey can be an alternative material for the split-thickness skin graft donor site treatment. [source] Sclerosing Foam in the Treatment of Varicose Veins and Telangiectases: History and Analysis of Safety and ComplicationsDERMATOLOGIC SURGERY, Issue 1 2002Alessandro Frullini MD objective. To review the use of sclerosing foam in the treatment of varicose veins, to describe the different techniques of foam preparation, and to report the complications of our 3-year experience with this treatment. method. From November 1997 to the end of October 2000, 453 patients were treated with a sclerosing foam for large, medium, and minor varicosities with sodium tetradecylsulfate (STS) or polidocanol (POL). A first group of 257 patients (90 for minor varicosities and 167 for medium to large veins) received a sclerosing foam according to the Monfreux technique. From December 1999 to October 2000, 196 patients were treated with a sclerosing foam prepared according to Tessari's method (36 for minor size veins or teleangectasias and 170 for medium-large veins). Every patient was studied with (color-flow) duplex scanning before and after the treatment and large vein injections were administered under duplex guide. results. The immediate success rate was 88.1% in the first group for the medium-large veins. In the same districts we registered an early success rate in 93.3% for the patients treated with the Tessari's method. The complication rate (mostly minor complications) was 8.5% in the first group and 7.1% in the second group. conclusion. The use of sclerosing foam may become an established therapy in the treatment of varicose veins with a high success rate, low cost, and low major complication rate. According to our actual experience and knowledge, the safe amount of foam should not exceed the 3-ml limit, but further advancements could come from standardization of the foam preparation technique. [source] Expression of zebrafish nos2b surrounds oral cavityDEVELOPMENTAL DYNAMICS, Issue 6 2008Kar-Lai Poon Abstract Inducible nitric oxide synthase (NOS2) catalyzes the production of nitric oxide (NO), and is one of the factors establishing innate immunity. In zebrafish, Nos2 is represented by nos2a and nos2b. Here, we report the cloning and expression pattern of the zebrafish nos2b gene, which does not seem to participate in induced immune response. nos2b was mapped to zebrafish linkage group 15. The spatial and temporal expression pattern of nos2b in embryonic zebrafish was analyzed by whole-mount in situ hybridization. nos2b is expressed constitutively in two primordia located along the ventral midline. The first group of cells contributes to the neurohypophysis. Initially at the level of the ventral hindbrain, the second group of cells migrates closely with the thyroid primordium to its final position at the basihyal by 3 dpf. Thus, the analysis of expression pattern of nos2b reveals complex morphogenetic movements resulting in its expression surrounding the oral cavity. Developmental Dynamics 237:1662,1667, 2008. © 2008 Wiley-Liss, Inc. [source] Fine-needle aspiration cytology in the follow-up of Hodgkin lymphomaDIAGNOSTIC CYTOPATHOLOGY, Issue 7 2008Pio Zeppa M.D. Abstract Hodgkin lymphoma (HL) is characterized by long survival and risk of relapse and second neoplasm. The aim of this study is to evaluate the possibility of improving the accuracy of fine-needle cytology (FNC) in HL follow-up using Power Doppler ultrasound (US) assistance and immediate microscopic evaluation (ICE). The study was performed in two consecutive groups of 200 FNC in HL patients. In the first group FNC of palpable lymph-nodes or extra lymph-nodal masses were performed without US assistance except for impalpable and/or deep located masses (nonassisted group); In the second group, all the FNC were performed under Power Doppler US assistance with ICE and immediately repeated in inadequate cases (assisted group). Cytological diagnoses were controlled by histology (61) or clinical follow-up (69); sensitivity and specificity were calculated in the two groups and to evaluate the effect of Power Doppler alone, adequate cases were compared with the total number of FNC in each of the two groups. FNC identified 90 negative cases, 3 false negatives, 70 HL relapse, 16 inadequate and 14 suspicious; second neoplasia were diagnosed in 12 cases and all histologically confirmed. Sensitivity and specificity were 64 and 84% in the nonassisted group and 86 and 94% in the assisted group and there were significant differences between the number of adequate cases v.s. the total number of FNC in each of the two groups. Sensitivity and specificity in assisted FNC are higher than in nonassisted ones. The main advantage of assisted FNC in the follow-up of HL is to produce accurate diagnoses avoiding invasive biopsies. Diagn. Cytopathol. 2008;36:467,472. © 2008 Wiley-Liss, Inc. [source] BIODIVERSITY RESEARCH: Population expansion in an invasive grass, Microstegium vimineum: a test of the channelled diffusion modelDIVERSITY AND DISTRIBUTIONS, Issue 5 2010Nathaniel P. Miller Abstract Aim, The greatest biodiversity impact of non-native plant species is caused by rapid expansion of colonist populations. Unfortunately, invasion has rarely been documented in real time at a population scale, and demographic mechanisms of invasion remain unclear. Our goal is to describe real-time expansion of populations, using channelled diffusion as a null model. Location, The study examined three populations of the invasive annual grass Microstegium vimineum in mature second-growth forests of south-eastern Ohio and nearby West Virginia, USA. Methods, Distributions were recorded in belt transects perpendicular to population edges over a period of 3 years. A second group of belt transects documented spread along five types of potential movement corridor. Observed changes in distribution were compared with predictions from a diffusion model. A seed-sowing experiment tested seed availability, microsite quality and proximity to potential movement corridors as factors controlling population spread. Results, Population boundaries showed little change over the study period. Colonization was limited by propagule availability over distances as little as 0.25 m, and to a lesser extent by litter cover. Populations did not advance along several potential movement corridors including unpaved roads, off-road vehicle trails and footpaths. Advance was observed along deer trails and stream courses but did not conform to the wave-form distribution predicted by diffusion theory. During the study, seeds were moved out of experimental plots by sheet flow and minor flooding events along small streams. Main conclusion, At a population level, invasion is driven by processes that are episodic in time and non-random in space , probably a common condition in non-native plant species. Spatially realistic models are likely to be more useful than diffusive models in managing invasions at these scales. [source] Seismic risk assessments and GIS technology: applications to infrastructures in the Friuli,Venezia Giulia region (NE Italy)EARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 11 2003Raffaella Codermatz Abstract This paper illustrates the seismic risk preliminary estimates of two different groups of structures located on the territory of the Friuli,Venezia Giulia region (NE Italy) : the first group includes some special industrial plants, and the second group includes bridges and tunnels belonging to the regional highway network. The part of the study on special industrial plants tries to evaluate the degree of expected damage, taking into account their structural typology and ground shaking expressed in terms of macroseismic intensity. The second part of the study is an application of the HAZUS methodology to the tunnels and bridges of a highway network: the combination of expected ground shaking and the construction characteristics lead to very different risk levels, especially when considering the bridges. The resulting damage levels to bridges and tunnels are still only indicative because of the fragility curves used in the evaluations: they were developed for existing bridge and tunnel structural typologies in the U.S.A. Moreover, both examples show the power of GIS technology in storing, elaborating, and mapping spatial data. Copyright © 2003 John Wiley & Sons, Ltd. [source] Disruptiveness, peer experiences and adolescent smoking: a long-term longitudinal approachADDICTION, Issue 4 2009Roy Otten ABSTRACT Aims This study examined links of peer experiences (i.e. social status and affiliation with disruptive peers) throughout childhood with respect to adolescent smoking trajectories, after controlling for childhood disruptiveness. Specifically, we tested four models regarding links of peer experiences and deviant behaviours. Design Prospective community sample. Participants A total of 312 children, aged 6.17 years at baseline. Measurements Growth parameters of own disruptive behaviour, disruptive behaviour of friends and social status measured at ages 7,12 years as predictors of smoking assessed at ages 13,15 years, while controlling for own disruptive behaviour at age 6 years. Findings We found three groups with distinct profiles of smoking. One group displayed hardly any or no smoking at all; a second group showed a trajectory of increased smoking; and a third group that showed high smoking rates initially and increased in smoking intensity over time. Results support the assumption of the selection model that the link between disruptive peers and smoking is spurious and due to shared variances with own early disruptiveness. Moreover, support was found for the popularity,socialization model supporting the assumption that age-related increases in social status are associated with smoking. Conclusions The findings emphasize that early disruptiveness is predictive of later smoking. In addition, it was shown that smoking becomes less deviant over time, in line with group norms. Future prevention programmes should emphasize the need to change these norms. [source] Substrate incorporation patterns of bacterioplankton populations in stratified and mixed waters of a humic lakeENVIRONMENTAL MICROBIOLOGY, Issue 7 2009Ulrike Buck Summary Bacterial incorporation of glucose, leucine, acetate and 4-hydroxybenzoic acid (HBA) was investigated in an artificially divided humic lake (Grosse Fuchskuhle, Germany). Two basins with contrasting influx of allochthonous organic carbon were sampled during late summer stratification (oxic and anoxic layers) and after autumn mixing. High total and cell-specific incorporation rates were observed for glucose and HBA in stratified and mixed waters respectively, but only a small fraction of bacteria visibly incorporated HBA. The oxic layer of the more humic-rich basin featured a significantly lower fraction of glucose incorporating cells and substantially higher proportions of acetate assimilating bacteria. Niche differentiation was observed in two betaproteobacterial populations: cells affiliated with the Polynucleobacter C subcluster efficiently incorporated acetate but little glucose, whereas the opposite was found for members of the R-BT065 clade. By contrast, leucine incorporation was variable in both taxa. Considering the high concentrations and rapid photochemical generation of organic acids in humic waters our results may help to explain the success of the Polynucleobacter C lineage in such habitats. Specific substrate or habitat preferences were also present in three subgroups of the actinobacterial acI lineage: The numerically dominant clade in oxic waters (acI-840-1) was absent in the anoxic zone and did not incorporate acetate. A second group (acI-840-2) was found both in the epi- and hypolimnion, whereas the third one (acI-840-3) only occurred in anoxic waters. Altogether our results suggest a constitutive preference for some substrates versus an adaptive utilization of others in the studied microbial groups. [source] Genetic variation among Fusarium oxysporum isolates from cucumberEPPO BULLETIN, Issue 2 2000D. J. Vakalounakis Isolates of Fusarium oxysporum obtained from cucumber worldwide were classified into 3 groups by random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR). All isolates of f. sp. radicis-cucumerinum fall into one group. Isolates of races 1 and 2 of f. sp. cucumerinum fall into a second group related to isolates of f. sp. melonis and niveum. Isolates of race 3 fall into a third group, related to f. sp. momordicae. Because f. sp. radicis-cucumerinum has relatively recently been introduced into Greece, where it is actively spreading and very damaging, RAPD-PCR may be valuable in monitoring populations of F. oxysporum. [source] Kv1 currents mediate a gradient of principal neuron excitability across the tonotopic axis in the rat lateral superior oliveEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2004Margaret Barnes-Davies Abstract Principal neurons of the lateral superior olive (LSO) detect interaural intensity differences by integration of excitatory projections from ipsilateral bushy cells and inhibitory inputs from the medial nucleus of the trapezoid body. The intrinsic membrane currents active around firing threshold will form an important component of this binaural computation. Whole cell patch recording in an in vitro brain slice preparation was employed to study conductances regulating action potential (AP) firing in principal neurons. Current-clamp recordings from different neurons showed two types of firing pattern on depolarization, one group fired only a single initial AP and had low input resistance while the second group fired multiple APs and had a high input resistance. Under voltage-clamp, single-spiking neurons showed significantly higher levels of a dendrotoxin-sensitive, low threshold potassium current (ILT). Block of ILT by dendrotoxin-I allowed single-spiking cells to fire multiple APs and indicated that this current was mediated by Kv1 channels. Both neuronal types were morphologically similar and possessed similar amounts of the hyperpolarization-activated nonspecific cation conductance (Ih). However, single-spiking cells predominated in the lateral limb of the LSO (receiving low frequency sound inputs) while multiple-firing cells dominated the medial limb. This functional gradient was mirrored by a medio-lateral distribution of Kv1.1 immunolabelling. We conclude that Kv1 channels underlie the gradient of LSO principal neuron firing properties. The properties of single-spiking neurons would render them particularly suited to preserving timing information. [source] ON QUANTIFYING TOLERANCE OF HERBIVORY FOR COMPARATIVE ANALYSESEVOLUTION, Issue 9 2008Michael J. Wise As the evolutionary importance of plant tolerance of herbivory is increasingly appreciated, more and more studies are not just measuring a plant's tolerance, but are comparing tolerance among plant genotypes, populations, species, and environments. Here, we suggest that caution must be taken in such comparative studies in the choice of measurement scales (and data transformations) for damage levels and plant performance. We demonstrate with a simple scenario of two plant groups of equal tolerance how the choice of scales can lead one to infer that the first group is more tolerant, the second group is more tolerant, or the two groups are equally tolerant,using the identical dataset. We conclude that to make reliable, logically consistent inferences when comparing tolerances among groups of plants, damage and performance should both be on an additive scale or both on a multiplicative scale. [source] VICARIANCE AND DISPERSAL ACROSS BAJA CALIFORNIA IN DISJUNCT MARINE FISH POPULATIONSEVOLUTION, Issue 7 2003Giacomo Bernardi Abstract., Population disjunctions, as a first step toward complete allopatry, present an interesting situation to study incipient speciation. The geological formation of the Baja California Peninsula currently divides 19 species of fish into disjunct populations that are found on its Pacific Coast and in the northern part of the Gulf of California (also called the Sea of Cortez), but are absent from the Cape (Cabo San Lucas) region. We studied the genetic makeup of disjunct populations for 12 of these 19 fish species. Phylogeographic patterns for the 12 species can be separated into two major classes: a first group (eight species) showed reciprocal monophyly and high genetic divergence between disjunct populations. A second group (four species) displayed what appeared to be panmictic populations. Population structure between Pacific Coast populations, across the Punta Eugenia biogeographic boundary, was also evaluated. While dispersal potential (inferred by pelagic larval duration) was a poor predictor of population structure between Gulf of California and Pacific populations, we found that population genetic subdivision along the Pacific Coast at Punta Eugenia was always positively correlated with differentiation between Pacific and Gulf of California populations. Vicariant events, ongoing gene flow, and ecological characteristics played essential roles in shaping the population structures observed in this study. [source] Voltage-gated sodium channel isoform-specific effects of pompilidotoxinsFEBS JOURNAL, Issue 4 2010Emanuele Schiavon Pompilidotoxins (PMTXs, , and ,) are small peptides consisting of 13 amino acids purified from the venom of the solitary wasps Anoplius samariensis (,-PMTX) and Batozonellus maculifrons (,-PMTX). They are known to facilitate synaptic transmission in the lobster neuromuscular junction, and to slow sodium channel inactivation. By using ,-PMTX, ,-PMTX and four synthetic analogs with amino acid changes, we conducted a thorough study of the effects of PMTXs on sodium current inactivation in seven mammalian voltage-gated sodium channel (VGSC) isoforms and one insect VGSC (DmNav1). By evaluating three components of which the inactivating current is composed (fast, slow and steady-state components), we could distinguish three distinct groups of PMTX effects. The first group concerned the insect and Nav1.6 channels, which showed a large increase in the steady-state current component without any increase in the slow component. Moreover, the dose-dependent increase in this steady-state component was correlated with the dose-dependent decrease in the fast component. A second group of effects concerned the Nav1.1, Nav1.2, Nav1.3 and Nav1.7 isoforms, which responded with a large increase in the slow component, and showed only a small steady-state component. As with the first group of effects, the slow component was dose-dependent and correlated with the decrease in the fast component. Finally, a third group of effects concerned Nav1.4 and Nav1.5, which did not show any change in the slow or steady-state component. These data shed light on the complex and intriguing behavior of VGSCs in response to PMTXs, helping us to better understand the molecular determinants explaining isoform-specific effects. [source] Probing the unfolding region of ribonuclease A by site-directed mutagenesisFEBS JOURNAL, Issue 20 2004Jens Köditz Ribonuclease A contains two exposed loop regions, around Ala20 and Asn34. Only the loop around Ala20 is sufficiently flexible even under native conditions to allow cleavage by nonspecific proteases. In contrast, the loop around Asn34 (together with the adjacent ,-sheet around Thr45) is the first region of the ribonuclease A molecule that becomes susceptible to thermolysin and trypsin under unfolding conditions. This second region therefore has been suggested to be involved in early steps of unfolding and was designated as the unfolding region of the ribonuclease A molecule. Consequently, modifications in this region should have a great impact on the unfolding and, thus, on the thermodynamic stability. Also, if the Ala20 loop contributes to the stability of the ribonuclease A molecule, rigidification of this flexible region should stabilize the entire protein molecule. We substituted several residues in both regions without any dramatic effects on the native conformation and catalytic activity. As a result of their remarkably differing stability, the variants fell into two groups carrying the mutations: (a) A20P, S21P, A20P/S21P, S21L, or N34D; (b) L35S, L35A, F46Y, K31A/R33S, L35S/F46Y, L35A/F46Y, or K31A/R33S/F46Y. The first group showed a thermodynamic and kinetic stability similar to wild-type ribonuclease A, whereas both stabilities of the variants in the second group were greatly decreased, suggesting that the decrease in ,G can be mainly attributed to an increased unfolding rate. Although rigidification of the Ala20 loop by introduction of proline did not result in stabilization, disturbance of the network of hydrogen bonds and hydrophobic interactions that interlock the proposed unfolding region dramatically destabilized the ribonuclease A molecule. [source] Invasion of a karst aquifer by hydrothermal fluids: evidence from stable isotopic compositions of cave mineralizationGEOFLUIDS (ELECTRONIC), Issue 2 2001S. H. Bottrell Abstract Mineral deposits in the Cupp-Coutunn/Promeszutochnaya cave system (Turkmenia, central Asia) record a phase of hydrothermal activity within a pre-existing karstic groundwater conduit system. Hydrothermal fluids entered the caves through fault zones and deposited sulphate, sulphide and carbonate minerals under phreatic conditions. Locally, intense alteration of limestone wall rocks also occurred at this stage. Elsewhere in the region, similar faults contain economic quantities of galena and elemental sulphur mineralization. Comparisons between the Pb and S isotope compositions of minerals found in cave and ore deposits confirm the link between economic mineralization and hydrothermal activity at Cupp-Coutunn. The predominance of sulphate mineralization in Cupp-Coutunn implies that the fluids were more oxidized in the higher permeability zone associated with the karst aquifer. A slight increase in the ,34S of sulphate minerals and a corresponding ,34S decrease in sulphides suggest that partial isotopic equilibration occurred during oxidation. Carbonate minerals indicate that the hydrothermal fluid was enriched in 18O (,18OSMOW , + 10,) relative to meteoric groundwater and seawater. Estimated values for ,13CDIC (,13CPDB , , 13,) are consistent with compositions expected for dissolved inorganic carbon (DIC) derived from the products of thermal decomposition of organic matter and dissolution of marine carbonate. Values derived for ,13CDIC and ,18Owater indicate that the hydrothermal fluid was of basinal brine origin, generated by extensive water,rock interaction. Following the hydrothermal phase, speleothemic minerals were precipitated under vadose conditions. Speleothemic sulphates show a bimodal sulphur isotope distribution. One group has compositions similar to the hydrothermal sulphates, whilst the second group is characterized by higher ,34S values. This latter group may either record the effects of microbial sulphate reduction, or reflect the introduction of sulphate-rich groundwater generated by the dissolution of overlying evaporites. Oxygen isotope compositions show that calcite speleothems were precipitated from nonthermal groundwater of meteoric origin. Carbonate speleothems are relatively enriched in 13C compared to most cave deposits, but can be explained by normal speleothem-forming processes under thin, arid-zone soils dominated by C4 vegetation. However, the presence of sulphate speleothems, with isotopic compositions indicative of the oxidation of hydrothermal sulphide, implies that CO2 derived by reaction of limestone with sulphuric acid (,condensation corrosion') contributed to the formation of 13C-enriched speleothem deposits. [source] Schwann cells and the pathogenesis of inherited motor and sensory neuropathies (Charcot-Marie-Tooth disease)GLIA, Issue 4 2006Philipp Berger Abstract Over the last 15 years, a number of mutations in a variety of genes have been identified that lead to inherited motor and sensory neuropathies (HMSN), also called Charcot-Marie-Tooth disease (CMT). In this review we will focus on the molecular and cellular mechanisms that cause the Schwann cell pathologies observed in dysmyelinating and demyelinating forms of CMT. In most instances, the underlying gene defects alter primarily myelinating Schwann cells followed by secondary axonal degeneration. The first set of proteins affected by disease-causing mutations includes the myelin components PMP22, P0/MPZ, Cx32/GJB1, and periaxin. A second group contains the regulators of myelin gene transcription EGR2/Krox20 and SOX10. A third group is composed of intracellular Schwann cells proteins that are likely to be involved in the synthesis, transport and degradation of myelin components. These include the myotubularin-related lipid phosphatase MTMR2 and its regulatory binding partner MTMR13/SBF2, SIMPLE, and potentially also dynamin 2. Mutations affecting the mitochondrial fission factor GDAP1 may indicate an important contribution of mitochondria in myelination or myelin maintenance, whereas the functions of other identified genes, including NDRG1, KIAA1985, and the tyrosyl-tRNA synthase YARS, are not yet clear. Mutations in GDAP1, YARS, and the pleckstrin homology domain of dynamin 2 lead to an intermediate form of CMT that is characterized by moderately reduced nerve conduction velocity consistent with minor myelin deficits. Whether these phenotypes originate in Schwann cells or in neurons, or whether both cell types are directly affected, remains a challenging question. However, based on the advances in systematic gene identification in CMT and the analyses of the function and dysfunction of the affected proteins, crucially interconnected pathways in Schwann cells in health and disease have started to emerge. These networks include the control of myelin formation and stability, membrane trafficking, intracellular protein sorting and quality control, and may extend to mitochondrial dynamics and basic protein biosynthesis. © 2006 Wiley-Liss, Inc. [source] Liver stiffness identifies two different patterns of fibrosis progression in patients with hepatitis C virus recurrence after liver transplantation,HEPATOLOGY, Issue 1 2010José A. Carrión Significant liver fibrosis (F , 2) and portal hypertension (hepatic venous pressure gradient [HVPG] , 6 mmHg) at 1 year after liver transplantation (LT) identify patients with severe hepatitis C recurrence. We evaluated whether repeated liver stiffness measurements (LSM) following LT can discriminate between slow and rapid "fibrosers" (fibrosis stage F2-F4 at 1 year after LT). Eighty-four patients who had undergone LT and who were infected with hepatitis C virus (HCV) and 19 LT controls who were not infected with HCV underwent LSM at 3, 6, 9, and 12 months after LT. All HCV-infected patients underwent liver biopsy 12 months after LT (paired HVPG measurements in 74); 31 (37%) were rapid fibrosers. Median LSM (in kilopascal) at months 6, 9, and 12 were significantly higher in rapid fibrosers (9.9, 9.5, 12.1) than in slow fibrosers (6.9, 7.5, 6.6) (P < 0.01 all time points). The slope of liver stiffness progression (kPa × month) in rapid fibrosers (0.42) was significantly greater than in slow fibrosers (0.05) (P < 0.001), suggesting two different speeds of liver fibrosis progression. Figures were almost identical for patients with HVPG , 6 mmHg or HVPG < 6 mmHg at 1 year after LT. Multivariate analysis identified donor age, bilirubin level, and LSM as independent predictors of fibrosis progression and portal hypertension in the estimation group (n = 50) and were validated in a second group of 34 patients. The areas under the receiver operating characteristic curve that could identify rapid fibrosers and patients with portal hypertension as early as 6 months after LT were 0.83 and 0.87, respectively, in the estimation group and 0.75 and 0.80, respectively, in the validation group. Conclusion: Early and repeated LSM following hepatitis C recurrence in combination with clinical variables discriminates between rapid and slow fibrosers after LT. (HEPATOLOGY 2009.) [source] Histological grading of invasive breast carcinoma , a simplification of existing methods in a large conservation series with long-term follow-upHISTOPATHOLOGY, Issue 6 2009Jeremy St J Thomas Aims:, To assess the validity of grading in the Edinburgh Breast Conservation Series; a consecutive cohort of 1812 early breast cancer patients treated by breast conservation and radiotherapy between 1981 and 1998 in a single specialist centre with ,9 years' follow-up and full staging data. Methods and results:, A single pathologist (J.St.J.T) graded 1650 cases using the Elston and Ellis method (EE) with particular reference to the component data: acinar differentiation, nuclear pleomorphism and mitotic counts. The original method was then compared with binary scoring of the same components and the relationship to prognosis reassessed. EE grades and individual grade components were prognostic (P < 0.0001) with 10-year cause-specific survival of 95.6%, 86.4% and 74.7% for EE grades 1, 2 and 3, respectively. A binary scoring of grade components produces four groups, splitting EE grade 2 tumours into two groups with different outcomes , 10-year survival rates for the four revised grades were 96.0%, 89.0%, 79.7% and 75.4%, respectively. Conclusions:, Existing grading methodology is fully applicable in the narrower context of a conservation series but can be simplified. Subdivision of EE grade 2 into a true intermediate prognosis group and a second group with a worse prognosis also adds benefit. [source] Response of refractory colitis to intravenous or oral tacrolimus (FK506)INFLAMMATORY BOWEL DISEASES, Issue 5 2002Dr. Klaus Fellermann Abstract Intravenous cyclosporine has proven to be an alternative to emergency colectomy in steroid-refractory ulcerative colitis, whereas the experience with FK506 is limited. In this report we compare intravenous to oral FK506 treatment in 38 patients with refractory ulcerative (n = 33) or indeterminate (n = 5) colitis. FK506 was started intravenously in the first group (n = 18) at a dose of 0.01 to 0.02 mg/kg up to 14 days, followed by 0.1 to 0.2 mg/kg orally, or was started orally at this dose in a second group (n = 20). Additional azathioprine/6-mercaptopurine was given and steroids were tapered in responding patients, followed by a dose reduction of FK506. Clinical disease activity and laboratory parameters were assessed to evaluate efficacy and safety. Primary objectives were the induction of remission (Truelove index of mild) and colectomy-free survival. Treatment lasted for a mean of 7.6 months, and the mean observation period was 16.2 months. Eighteen of 38 patients improved within 14 days, and a complete remission was achieved in 13 patients after 1 month. A colectomy within 1 month was performed in 3 of 38 patients. The overall colectomy rate was 34%. One-half of the patients with a minimum follow-up of 2 years required a colectomy. Intravenous and per oral administration were equally safe and effective. The most frequent adverse events included tremor, hyperglycemia, hypertension, and infection, but none were severe. Renal impairment was rare and subsided upon drug withdrawal. In conclusion, FK506 is effective in the treatment of refractory colitis with per oral dosing being equivalent to intravenous administration. [source] Percentage of filled canal area in mandibular molars after conventional root-canal instrumentation and after a noninstrumentation technique (NIT)INTERNATIONAL ENDODONTIC JOURNAL, Issue 9 2003C. N. Ardila Abstract Aim, To compare the percentage of filled canal area in mandibular molar roots after using conventional root-canal hand instrumentation or after a noninstrumentation technique (NIT). Methodology, Forty mandibular molars were used shortly after extraction. The root canals of 20 molars in the manual group were conventionally prepared using hand instruments and then filled with warm vertical compaction of gutta-percha. The 20 teeth in the second group were cleaned and obturated by NIT. In each case, the entire molar, including the crown and the roots, was embedded in an acrylic resin cylinder before NIT. Horizontal sections were cut at 2, 4, 6 and 8 mm from the apex. Images of the sections were taken using a microscope at ×40 magnification and a digital camera; the images were scanned as Tagged Image File Format (TIFF) images into a PC. The cross-sectional area of the canal with the filling materials was measured using an image analysis programme. The percentage of filled area was calculated. The difference in the percentage of filled canal area between the two groups was analysed using a Student's t -test. Results, At all levels, 93,100% of the canal area was filled in both groups. No significant difference was found between the manual technique and the NIT technique at any level (P > 0.05). Conclusions, Within the limitations of this study, following the cleaning and filling of root canals using NIT, the percentage of filled root canal was similar to that using warm vertical compaction of gutta-percha after conventional root-canal instrumentation. [source] Influence of rotational speed, torque and operator proficiency on failure of Greater Taper filesINTERNATIONAL ENDODONTIC JOURNAL, Issue 1 2002G. M. Yared Abstract Aim The purpose of this study was to evaluate the influence of rotational speed, torque, and operator experience on the incidence of locking, deformation, and separation of instruments when using a specific Ni,Ti rotary instrumentation technique in extracted human teeth. Methodology Greater Taper Ni,Ti rotary instruments (GT) were used in a crown-down technique. In one group (rotational speed evaluation) of canals (n = 300) speeds of 150, 250 and 350 r.p.m. (subgroups 1, 2 and 3) were used. Each one of the subgroups included 100 canals. In a second group (evaluation of torque) (n = 300) torque was set at 20, 30 and 55 Ncm (subgroups 4, 5 and 6). In the third group (evaluation of operator proficiency) (n = 300) three operators with varying experience (subgroups 7, 8 and 9) were also compared. Each subgroup included the use of 10 sets of GT rotary instruments and 100 canals of extracted human molars. Each set of instruments was used in up to 10 canals and sterilized before each case. NaOCl 2.5% was used as an irrigant. The number of locked, deformed, and separated instruments was recorded for each group. Statistical analysis was carried out with pairwise comparisons using Fisher's exact tests for each of the failure type. Results When the influence of rotational speed was evaluated, instrument deformation and separation did not occur in subgroups 1 (150 r.p.m.), 2 (250 r.p.m.), and 3 (350 r.p.m.). Instrument locking occurred in subgroup 3 only. Statistical analysis demonstrated a significant difference between the 150 and 350 r.p.m. groups and between the 250 and 350 r.p.m. groups with respect to instrument locking. In torque evaluation, neither separation, deformation nor locking occurred during the use of the instruments, at 150 r.p.m., and at the different torque values. When the operators were compared, although two instruments were separated in canals prepared by the least experienced operator, Fisher's exact tests did not demonstrate a significant difference between the three subgroups. Instrument locking, deformation, and separation did not occur with the most experienced operator. None of the instruments separated with the trained operator. Conclusions Preclinical training in the use of the GT rotary instruments when used with a crown-down technique at 150 r.p.m. was crucial in avoiding instrument separation and reducing the incidence of instrument locking and deformation. [source] Does chloroquine therapy of porphyria cutanea tarda influence liver pathology?INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 11 2009U Wollina MD Background, Porphyria cutanea tarda (PCT) is regularly associated with changes in liver tissue. On the other hand, systematic investigations are lacking on whether there is a correlation between the severity of liver damage and chloroquine treatment. Patients and methods, During a 20-year period, liver biopsies were obtained in 89 patients with PCT confirmed by biochemical analysis of urine and feces and low-dose chloroquine therapy. Seventeen patients with alcohol-induced liver disease were excluded. In 8 of 63 patients, only a single biopsy was available. Classification of liver damage was performed according to the Riedel score. Electron microscopy was available from 24 patients. In a second group of patients, the HFE status was investigated and Berlin blue stains of liver biopsies were performed. Results, There was no correlation between the duration of cutaneous symptoms and liver pathology. After 12 months chloroquine treatment, 45 patients (81%) disclosed an improvement of liver pathology, nine (16%) had no change, and a worsening was observed in one patient (3%). All patients achieved a complete clinical and biochemical remission. In 13 of 16 patients with a relapse, there was again a deterioration of liver damage. Patients with HFE mutations had a significant higher risk (P < 0.05) for hepatic siderosis. Conclusions, The severity of liver damage was not correlated with the disease duration. Chloroquine treatment resulted in PCT remission (clinical and biochemical) and in 81% to an improvement of liver morphology. [source] Predicting Hospital Admission and Returns to the Emergency Department for Elderly PatientsACADEMIC EMERGENCY MEDICINE, Issue 3 2010Michael A. LaMantia MD Abstract Objectives:, Methods to accurately identify elderly patients with a high likelihood of hospital admission or subsequent return to the emergency department (ED) might facilitate the development of interventions to expedite the admission process, improve patient care, and reduce overcrowding. This study sought to identify variables found among elderly ED patients that could predict either hospital admission or return to the ED. Methods:, All visits by patients 75 years of age or older during 2007 at an academic ED serving a large community of elderly were reviewed. Clinical and demographic data were used to construct regression models to predict admission or ED return. These models were then validated in a second group of patients 75 and older who presented during two 1-month periods in 2008. Results:, Of 4,873 visits, 3,188 resulted in admission (65.4%). Regression modeling identified five variables statistically related to the probability of admission: age, triage score, heart rate, diastolic blood pressure, and chief complaint. Upon validation, the c-statistic of the receiver operating characteristic (ROC) curve was 0.73, moderately predictive of admission. We were unable to produce models that predicted ED return for these elderly patients. Conclusions:, A derived and validated triage-based model is presented that provides a moderately accurate probability of hospital admission of elderly patients. If validated experimentally, this model might expedite the admission process for elderly ED patients. Our models failed, as have others, to accurately predict ED return among elderly patients, underscoring the challenge of identifying those individuals at risk for early ED returns. ACADEMIC EMERGENCY MEDICINE 2010; 17:252,259 © 2010 by the Society for Academic Emergency Medicine [source] A double blind, randomized, placebo controlled study to evaluate the efficacy of erythromycin in patients with knee effusion due to osteoarthritisINTERNATIONAL JOURNAL OF RHEUMATIC DISEASES, Issue 1 2009Shahram SADREDDINI Abstract Objective:, The efficacy of erythromycin in treatment of knee effusion due to osteoarthritis was evaluated. Method:, We assessed efficacy and safety of erythromycin during 16 weeks in patients enrolled in a randomized double-blind study. One hundred and eight patients with knee effusion due to osteoarthritis (OA) received 12-week courses of erythromycin or placebo allocated randomly, and were followed for 4 months. Acetaminophen 650 mg/day was used in both groups, while they received no other anti-inflammatory drugs (such as corticosteroid or nonsteroidal anti-inflammatory drugs) during the course of the study. Our patients were divided in two groups, erythromycin in doses of 200 mg four times per day was given to the first group (51 patients) over the first 3 months of the study and in the second group we used placebo with the same dosage and schedule (53 patients). Outcomes improvement for the erythromycin-treated group was assessed by a significantly higher mean score from baseline to the end of the trial, compared with placebo group. Patients were examined monthly during the treatment period. Measurement values included recording of Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire subscales (pain, stiffness and function), range of motion and knee circumference. Results:, Erythromycin produced a higher response rate than placebo in treatment of knee effusion due to OA. Significant reduction in knee circumference (P < 0.0005) and pain (P < 0.001) with functional improvement (P < 0.0005) were seen. At the first month after treatment, 11.8% (6 patients) in erythromycin and 9.4% (5 patients) in placebo groups had 50% pain reduction, which was not significant (P = 0.75). At the fourth month, 50% reduction of pain was seen in 45.1% (23 patients) of the erythromycin and 11.3% (6 patients) of the placebo group. This was statistically significant (P < 0.0005). Erythromycin treatment was well tolerated and mild adverse events caused no discontinuation during the study. Conclusion:, This is a placebo-controlled study of macrolid efficacy on knee effusion due to OA in a short period. Results of this research showed the better efficacy of erythromycin in controlling effusion and pain with functional improvement in patients with knee effusion due to OA. [source] The effects of education and training on clinical practice in wound healingINTERNATIONAL WOUND JOURNAL, Issue 5 2008Michael A Seeley Abstract This article considers the effects of two different types of educational programme on community nurse clinical practice in venous ulceration. One group of nurses (the experimental group) attended an educational programme designed to take account of training needs and learning styles. A second group of nurses (the control group) attended a standardised educational programme. A multiple-choice question examination and Objective Structured Clinical Examination were used to measure knowledge and skills. Kolb's Learning Styles Inventory was used to measure learning styles. Findings were that experimental nurses failed to show improved post-intervention clinical practice compared with the control group. [source] Debris flow and slide deposits at the top of the Internal Liguride ophiolitic sequence, Northern Apennines, Italy: A record of frontal tectonic erosion in a fossil accretionary wedgeISLAND ARC, Issue 1 2001Michele Marroni Abstract In the Northern Apennines, the Internal Liguride units are characterized by an ophiolite sequence that represents the stratigraphic base of a late Jurassic,early Paleocene sedimentary cover. The Bocco Shale represents the youngest deposit recognized in the sedimentary cover of the ophiolite and can be subdivided into two different groups of deep sea sediments. The first group is represented by slide, debris flow and high density turbidity current-derived deposits, whereas the second group consists of thin-bedded turbidites. Facies analysis and provenance studies indicate, for the former group, small and scarcely evoluted flows that rework an oceanic lithosphere and its sedimentary cover. We interpret the Bocco Shale as an ancient example of a deposit related to the frontal tectonic erosion of the accretionary wedge slope. The frontal tectonic erosion resulted in a large removal of materials, from the accretionary wedge front, that was reworked as debris flows and slide deposits sedimented on the lower plate above the trench deposits. The frontal tectonic erosion was probably connected with subduction of oceanic crust characterized by positive topographic relief. This interpretation can be also applied for the origin of analogous deposits of Western Alps and Corsica. [source] Anticipatory grieving among parents living with a child with cancerJOURNAL OF ADVANCED NURSING, Issue 9 2010Ekhlas Al-Gamal al-gamal e. & long t. (2010) Anticipatory grieving among parents living with a child with cancer. Journal of Advanced Nursing,66(9), 1980,1990. Abstract Aim., This paper is a report of a comparative study of anticipatory grief of parents of children newly diagnosed with cancer and those whose children were diagnosed 6,12 months earlier. Background., Public perceptions of cancer as a fatal illness persist despite improved prognosis for children. Parents may experience feelings of despair, hopelessness, and worthlessness , the most common psychological expressions of anticipatory grief. With a focus on developing more effective therapeutic intervention, healthcare professionals have developed greater interest in the concept of anticipatory grief. Method., One hundred and forty parents, divided between ,newly diagnosed' and ,6,12 months after diagnosis' groups, were recruited in 2006 from two hospitals representative of the healthcare sector in Jordan. Structured interviews were conducted to assess anticipatory grief, using the Marwit and Meuser Caregiver Inventory: Childhood Cancer. Analysis was performed using t -tests. Results., Fewer than half of the parents in both groups reported being at peace with themselves and their situation in life. Parents of newly diagnosed children reported more severe anticipatory grief responses than those in the second group. No statistically significant differences were found in responses between mothers and fathers. Conclusion., Healthcare professionals should encourage parents to discuss negative feelings related to their child's illness and potential outcome. Hospital policies need to include the provision and promotion of support group services for parents, and nurses should encourage parents to exploit such services. [source] Flea species richness and parameters of host body, host geography and host ,milieu'JOURNAL OF ANIMAL ECOLOGY, Issue 6 2004BORIS R. KRASNOV Summary 1We have assessed how different host parameters affect species richness of flea assemblages using the independent contrasts method. Three groups of host parameters were examined. The first group included host body parameters (body size, basal and average daily metabolic rates), the second group included parameters of geographical range size and position of this range in relation to the equator (latitude) and the third group comprised parameters related to the number of sympatric closely related species. 2None of the host body parameters correlated with species richness of flea assemblages. 3Flea species richness increased with an increase in latitude of the geographical range centre of a host as well as with an increase in a composite variable that described the size of the geographical range. 4The number of sympatric closely related species both across the entire geographical range and locally was correlated positively with species richness of fleas. 5Our results show that species richness of ectoparasites is affected little by parameters of the host body and to a greater extent by parameters related to the host environment. 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