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Posterior Regions (posterior + regions)
Selected AbstractsLangerhans cell histiocytosis: oral/periodontal involvement in adult patientsORAL DISEASES, Issue 8 2009S Annibali Objective:, Langerhans cell histiocytosis (LCH) is a clonal proliferative multisystem disease. Although bone and mucosae have been classified as non-risk organs, their involvement may increase the risk of disease progression. Oral and periodontal lesions are burdened with a significant impairment of quality of life for associated signs, symptoms and loss of function. Most of information regards paediatric disease; the disease in adults has received limited attention. Subjects and Methods:, A total of 31 adult patients affected by immuno-histopathology confirmed LCH have been prospectively examined; attention was paid to the occurrence and characterization of oral lesions. Results:, Twelve patients developed oral lesions. Posterior regions of jawbones were always affected; the involvement of anterior regions was not constant. Unifocal oral involvement was significantly associated with multisystemic disease while multifocal lesions were associated with unisystemic disease. Oral disease presented with soft tissue ulcers (50% of cases), gingival bleeding (66.7%), pain (83.4%), periodontal damage (50%), tooth mobility (16.7%), non-healing extraction socket (8.3%); 41.6% of patients complained of negative outcomes on quality of life. Oral lesions were easily handled with local measures. Conclusions:, Posterior regions require attention; single oral lesions may be part of multisystemic disease; oral and periodontal lesions may be early signs of disease reactivation. [source] Angelman Syndrome: Difficulties in EEG Pattern Recognition and Possible MisinterpretationsEPILEPSIA, Issue 8 2003Kette D. Valente Summary: Purpose: This study aimed to evaluate the sensitivity of the EEG in Angelman syndrome (AS), to verify the age at onset of suggestive EEGs and to study EEG patterns, analyzing variations and comparing our findings with nomenclature previously used. Methods: Seventy EEG and 15 V-EEGs of 26 patients were analyzed. Suggestive EEG patterns of AS were classified in delta pattern (DP), theta pattern (TP), and posterior discharges (PDs). Generic terms were used to simplify the analysis. Results: Suggestive EEGs were observed in 25 (96.2%) patients. DP occurred in 22 patients with four variants,hypsarrhythmic-like: irregular, high-amplitude, generalized delta activity (DA) with multifocal epileptiform discharges (EDs); slow variant: regular, high-amplitude, generalized DA with rare EDs; ill-defined slow spike-and-wave: regular, high-amplitude, generalized DA with superimposed EDs characterizing a slow wave, with notched appearance; triphasic-like: rhythmic, moderate-amplitude DA over anterior regions with superimposed EDs. TP was observed in eight patients, as generalized or over the posterior regions. PDs were seen in 19 patients as runs of sharp waves or runs of high-amplitude slow waves with superimposed EDs. TP was the only age-related pattern (younger than 8 years) and observed only in patients with deletion. In 15 patients who had an EEG before the clinical diagnosis, 60% had a suggestive tracing. Conclusions: Although some EEG descriptions are not very detailed, and every author describes findings in a slightly different manner, obviously a common denominator must exist. In this context, EEG seems to be a very sensitive method for the diagnosis of AS, offering an opportunity to corroborate this etiologic diagnosis. Conversely, we do not believe that these patterns may be accounted as specific, except for the delta pattern, which seems to be extremely unusual in other syndromes. Other EEG patterns observed in AS, such as theta activity and PDs, occur in a wide variety of disorders. Nonetheless, their importance for the EEG diagnosis of AS is supported by the fact that they are associated with other features and may be helpful in a proper clinical setting. [source] Benign Partial Epilepsies of Adolescence: A Report of 37 New CasesEPILEPSIA, Issue 12 2001G. Capovilla Summary: ,Purpose: To delineate the electroclinical features of patients with partial seizures in adolescence with a benign outcome. Methods: Patients were recruited in five different Italian epilepsy centers. Patients were selected among those with partial seizures between ages 11 and 17 years. We excluded benign childhood epilepsies, those with neurologic or mental deficits, and those with neuroradiologically documented lesions. We also excluded patients with less than 3 years' follow-up or who were still receiving antiepileptic therapy. Results: There were 37 (22 male, 15 female) patients. Seizures started at the mean age of 14.5 years (range, 11,16.11). Two main electroclinical patterns emerged: 16 of 37 patients had somatomotor seizures frequently associated with focal theta discharges involving the centroparietal regions. Ten of 37 patients showed versive seizures and interictal spiking involving the posterior regions. A third group had clinical characteristics resembling the cases described by Loiseau. All had a favorable outcome. Conclusions: This relevant multicenter study further confirms the existence of benign partial epilepsies with onset during adolescence. [source] Claustral Lesions Delay Amygdaloid Kindling in the RatEPILEPSIA, Issue 9 2000Paul Mohapel Summary: Purpose: Lesions of the claustrum in cats and primates have been shown to disrupt the development and expression of amygdaloid-kindled seizures in cats and primates. Because the structure and connectivity of the claustrum can vary between species, we wanted to examine the effects of claustral lesions on kindling in rats. Methods: One group of rats received bilateral radiofrequency lesions of both anterior and posterior regions of the claustrum before amygdaloid kindling. Another group of rats received bilateral anterior and posterior radiofrequency lesions of the claustrum after amygdaloid kindling. Some rats were tested for transfer of kindling to the contralateral amygdala after claustral lesions. Results: Small lesions that destroyed 13% of the claustrum were capable of delaying, but not blocking, amygdaloid kindling. The delay in kindling was due to an increase in the stimulation trials required to kindle to stage 5 seizures. The lesions had no effect on established kindled seizures or on transfer to the contralateral amygdala. Conclusions: As in other species, the claustrum in the rat appears to play a role in kindling from the amygdala. Because of the restricted size of our claustral lesions, however, we were unable to conclusively assess the full extent of the claustrum's participation in limbic kindling. [source] A survey on undergraduate implant dentistry education in EuropeEUROPEAN JOURNAL OF DENTAL EDUCATION, Issue 2009H. De Bruyn Abstract Introduction:, The aim of the survey was to assess the status of implant dentistry education and addressed various aspects related to competence level, practical implementation and barriers for further development in the field. Materials and methods:, An e-mail survey was performed amongst 73 opinion leaders from 18 European countries invited to the Association for Dental Education in Europe (ADEE) workshop on implant dentistry. Results:, Forty-nine surveys were returned (67%) and it was found that theoretical and pre-clinical courses to an average of 36 h are given to undergraduates; 70% reported that students assist or treat patients with prosthetics; 53% reported that students assist with surgery and only 5% is operating patients. In 23% of the schools optional undergraduate courses are available and 90% offer postgraduate training. Barriers for including prosthetics and surgery are lack of time, funding or staff. Partial restorations, including surgery, in the posterior regions may be provided by dentists after attendance at additional courses but complex treatments should be limited to specialists. Conclusion:, This survey confirms that implant dentistry is part of the undergraduate curriculum, albeit with a disparity in time. Whereas implant dentistry is an important part of clinical practice, coverage in the curriculum is limited and when compared with 10 years ago, even stagnating. Priorities within the curriculum should be evaluated depending on demands and treatment needs of the population. To optimise education, learning guidelines should be developed, based on the expected competencies for practicing dentists. Undergraduate education may start the process that must continue through all levels of education, including the postgraduate level. [source] Vestigial prototroch in a basal nemertean, Carinoma tremaphoros (Nemertea; Palaeonemertea)EVOLUTION AND DEVELOPMENT, Issue 4 2004S. A. Maslakova Summary Nemerteans have been alleged to belong to a protostome clade called the Trochozoa that includes mollusks, annelids, sipunculids, echiurids, and kamptozoans and is characterized by, among other things, the trochophore larva. The trochophore possesses a prototroch, a preoral belt of specialized ciliary cells, derived from the trochoblast cells. Nemertea is the only trochozoan phylum for which presence of the trochophore larva possessing a prototroch had never been shown. However, so little is known about nemertean larval development that comparing it with development of other trochozoans is difficult. Development in the nemertean clade Pilidiophora is via a highly specialized planktonic larva, the pilidium, and most of the larval body is lost during a drastic metamorphosis. Other nemerteans (hoplonemerteans and palaeonemerteans) lack a pilidium, and their development is direct, forming either an encapsulated or planktonic "planuliform" larva, producing a juvenile without a dramatic change in body plan. We show that early in the development of a member of a basal nemertean assemblage, the palaeonemertean Carinoma tremaphoros, large squamous cells cover the entire larval surface except for the apical and posterior regions. Although apical and posterior cells continue to divide, the large surface cells cleavage arrest and form a contorted preoral belt. Based on its position, cell lineage, and fate, we suggest that this belt corresponds to the prototroch of other trochozoans. Lack of differential ciliation obscures the presence of the prototroch in Carinoma, but differentiation of the trochoblasts is clearly manifested in their permanent cleavage arrest and ultimate degenerative fate. Our results allow a meaningful comparison between the development of nemerteans and other trochozoans. We review previous hypotheses of the evolution of nemertean development and suggest that a trochophore-like larva is plesiomorphic for nemerteans while a pilidium type of development with drastic metamorphosis is derived. [source] Temporal lobe grey matter volume in schizophrenia is associated with a genetic polymorphism influencing glycogen synthase kinase 3-, activityGENES, BRAIN AND BEHAVIOR, Issue 4 2010F. Benedetti At the crossroad of multiple pathways regulating trophism and metabolism, glycogen synthase kinase (GSK)3 is considered a key factor in influencing the susceptibility of neurons to harmful stimuli (neuronal resilience) and is a target for several psychiatric drugs that directly inhibit it or increase its inhibitory phosphorylation. Inhibition of GSK3 prevents apoptosis and could protect against the neuropathological processes associated with psychiatric disorders. A GSK3- ,promoter single-nucleotide polymorphism (rs334558) influences transcriptional strength, and the less active form was associated with less detrimental clinical features of mood disorders. Here we studied the effect of rs334558 on grey matter volumes (voxel-based morphometry) of 57 patients affected by chronic schizophrenia. Carriers of the less active C allele variant showed significantly higher brain volumes in an area encompassing posterior regions of right middle and superior temporal gyrus, within the boundaries of Brodmann area 21. The temporal lobe is the brain parenchymal region with the most consistently documented morphometric abnormalities in schizophrenia, and neuropathological processes in these regions develop soon at the beginning of the illness. These results support the interest for GSK3- ,as a factor affecting neuropathology in major behavioural disorders, such as schizophrenia, and thus as a possible target for treatment. [source] Embryo development of Corticium candelabrum (Demospongiae: Homosclerophorida)INVERTEBRATE BIOLOGY, Issue 3 2007Sonia De Caralt Abstract. Corticium candelabrum is a homosclerophorid sponge widespread along the rocky Mediterranean sublittoral. Scanning and transmission electron microscopy were used to describe the gametes and larval development. The species is hermaphroditic. Oocytes and spermatocytes are clearly differentiated in April. Embryos develop from June to July when the larvae are released spontaneously. Spermatic cysts originate from choanocyte chambers and spermatogonia from choanocytes by choanocyte mitosis. Oocytes have a nucleolate nucleus and a cytoplasm filled with yolk granules and some lipids. Embryos are surrounded by firmly interlaced follicular cells from the parental tissue. A thin collagen layer lies below the follicular cells. The blastocoel is formed by migration of blastomeres to the morula periphery. Collagen is spread through the whole blastocoel in the embryo, but is organized in a dense layer (basal lamina) separating cells from the blastocoel in the larva. The larva is a typical cinctoblastula. The pseudostratified larval epithelium is formed by ciliated cells. The basal zone of the ciliated cells contains lipid inclusions and some yolk granules; the intermediate zone is occupied by the nucleus; and the apical zone contains abundant electron-lucent vesicles and gives rise to cilia with a single cross-striated rootlet. Numerous paracrystalline structures are contained in vacuoles within both apical and basal zones of the ciliated cells. Several slightly differentiated cell types are present in different parts of the larva. Most cells are ciliated, and show ultrastructural particularities depending on their location in the larvae (antero-lateral, intermediate, and posterior regions). A few smaller cells are non-ciliated. Several features of the C. candelabrum larva seem to support the previously proposed paraphyletic position of homoscleromorphs with respect to the other demosponges. [source] Clinical evaluation of Procera AllCeram crowns in Japanese patients: results after 5 yearsJOURNAL OF ORAL REHABILITATION, Issue 11 2009Y. KOKUBO Summary, Procera AllCeram crowns were prospectively evaluated clinically in both anterior and posterior regions in Japanese. One-hundred and one crowns were fabricated for 57 patients at the Tsurumi University Dental Hospital from August 2001 to October 2002 and evaluated according to the California Dental Association (CDA) quality evaluation system at baseline and annually at all follow-up examinations for 5 years. The plaque index (PI) and gingival index (GI) were recorded, and chipping and fracture were checked at the same time as well. A total of 75 Procera AllCeram crowns were evaluated, and the cumulative survival rate was 90·2% over the 5-year clinical trial. Six crowns experienced fractures within the veneering porcelain and from aluminium oxide coping, all of which occurred on the premolar and molar regions, and they had to be removed. Small chipping was observed on three crowns. According to the CDA criteria, 98% of Procera AllCeram crowns were rated as satisfactory, and PI and GI were comparable to those of control teeth during the observation period. [source] Microstructural Corpus Callosum Anomalies in Children With Prenatal Alcohol Exposure: An Extension of Previous Diffusion Tensor Imaging FindingsALCOHOLISM, Issue 10 2009Jeffrey R. Wozniak Background:, Several studies have now shown corpus callosum abnormalities using diffusion tensor imaging (DTI) in children with fetal alcohol spectrum disorders (FASD) in comparison with nonexposed controls. The data suggest that posterior regions of the callosum may be disproportionately affected. The current study builds on previous efforts, including our own work, and moves beyond midline corpus callosum to probe major inter-hemispheric white matter pathways with an improved DTI tractographic method. This study also expands on our prior work by evaluating a larger sample and by incorporating children with a broader range of clinical effects including full-criteria fetal alcohol syndrome (FAS). Methods:, Participants included 33 children with FASD (8 FAS, 23 partial FAS, 2 static encephalopathy) and 19 nonexposed controls between the ages of 10 and 17 years. Participants underwent DTI scans and intelligence testing. Groups (FASD vs. controls) were compared on fractional anisotropy (FA) and mean diffusivity (MD) in 6 white matter tracts projected through the corpus callosum. Exploratory analyses were also conducted examining the relationships between DTI measures in the corpus callosum and measures of intellectual functioning and facial dysmorphology. Results:, In comparison with the control group, the FASD group had significantly lower FA in 3 posterior tracts of the corpus callosum: the posterior mid-body, the isthmus, and the splenium. A trend-level finding also suggested lower FA in the genu. Measures of white matter integrity and cognition were correlated and suggest some regional specificity, in that only posterior regions of the corpus callosum were associated with visual-perceptual skills. Correlations between measures of facial dysmorphology and posterior regions of the corpus callosum were nonsignificant. Conclusions:, Consistent with previous DTI studies, these results suggest that microstructural posterior corpus callosum abnormalities are present in children with prenatal alcohol exposure and cognitive impairment. These abnormalities are clinically relevant because they are associated with cognitive deficits and appear to provide evidence of abnormalities associated with prenatal alcohol exposure independent of dysmorphic features. As such, they may yield important diagnostic and prognostic information not provided by the traditional facial characteristics. [source] Clinical history and new prognostic indicators in metachromatic leukodystrophyJOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 2 2004U Del Carro Objective: To study clinical phenotypes and to increase knowledge of natural history of different variants of metachromatic leukodystrophy (MLD). Background: Little is known about factors influencing age of onset, progression rate and peripheral nerve involvement in MLD due to its rarity, heterogeneity and paucity of serial clinical and instrumental reports. Methods: 15 biochemically and molecularly characterized MLD patients were evaluated along a two-year follow-up period with clinical, electroneurographic (ENG) and brain MRI recordings. Results: Late infantile patients had a progressive and rapid course, whereas juvenile form showed marked variability. Different clinical presentations were associated with similar levels of ARSA activity; mutation screening indicated a high prevalence of rare or private mutations. In all late infantile and in the adult patient, ENG revealed a severe polyneuropathy. In juvenile patients a milder polyneuropathy or even normal tests were found. The earliest MRI change was periventricular white matter signal alterations, with initial involvement of posterior regions in a majority of late infantile patients, while in juvenile forms white matter lesions were mainly anterior. Conclusions: MLD course is highly variable and only partially influenced by age of onset, especially among juvenile patients. No clear-cut correlations exist between clinical phenotype and biochemical or molecular characterization. The presence of peripheral neuropathy at onset seems a strong indicator of a poorer clinical outcome. [source] Semantic integration in videos of real,world events: An electrophysiological investigationPSYCHOPHYSIOLOGY, Issue 1 2003Tatiana Sitnikova Event,related potentials (ERPs) discriminated between contextually appropriate and inappropriate objects appearing in video film clips of common activities. Incongruent objects elicited a larger negative,going deflection, which was similar to the N400 component described previously in association with words and static pictures and which has been argued to reflect the integration of semantic information into a mental representation of the preceding context. The onset of this potential occurred shortly after object presentation, indicating that semantic integration is a rapid online component of real,world perception. In addition, the anomalies in movies evoked a large late positive potential at posterior regions, suggesting that in event perception, semantic incongruity may trigger cognitive processes other than those mediating pure semantic integration. [source] Silent Functional Magnetic Resonance Imaging (fMRI) of Tonotopicity and Stimulus Intensity Coding in Human Primary Auditory Cortex,THE LARYNGOSCOPE, Issue 3 2004F. Zerrin Yetkin MD Abstract Objectives The aims of this study were to determine the feasibility of obtaining auditory cortex activation evoked by pure tones presented at threshold and suprathreshold hearing levels, to evaluate tonotopicity of the primary auditory cortex, and to determine the effect of stimulus intensity on auditory cortex activation using silent functional magnetic resonance imaging (fMRI). Methods Sixteen subjects with normal hearing underwent silent fMRI. An audiometer was used to deliver pure tones of 1,000, 2,000, and 4,000 Hz to the left ear. Two levels of acoustic stimulation were used: 1) threshold, hearing level determined in the scanner room and 2) suprathreshold, 70 dB hearing loss (HL). Tonotopicity and stimulus intensity coding was assessed on the basis of the location, extent, and amount of the auditory cortex activation. Results The localization of activation moved to more medial and posterior regions of the primary auditory cortex as the frequency of the pure tone increased. Compared with a threshold stimulus, a suprathreshold stimulus evoked the same regions with increased spatial extent. The average increase in the right auditory cortex activation in response to suprathreshold stimulus was 57% at 1,000, 51% at 2,000, and 45% at 4,000 Hz compared with that activated by the threshold stimulus. Conclusions Silent fMRI can be used to evaluate auditory cortex activation using low-intensity stimuli. The level of stimulus intensity increases the amount of auditory cortex activation and influences the fMRI mapping of the tonotopic organization of the primary auditory cortex. [source] The psychological and neurophysiological concomitants of mindfulness forms of meditationACTA NEUROPSYCHIATRICA, Issue 2 2007Belinda Ivanovski Objective:, To provide a comprehensive review and evaluation of the psychological and neurophysiological literature pertaining to mindfulness meditation. Methods:, A search for papers in English was undertaken using PsycINFO (from 1804 onward), MedLine (from 1966 onward) and the Cochrane Library with the following search terms: Vipassana, Mindfulness, Meditation, Zen, Insight, EEG, ERP, fMRI, neuroimaging and intervention. In addition, retrieved papers and reports known to the authors were also reviewed for additional relevant literature. Results:, Mindfulness-based therapeutic interventions appear to be effective in the treatment of depression, anxiety, psychosis, borderline personality disorder and suicidal/self-harm behaviour. Mindfulness meditation per se is effective in reducing substance use and recidivism rates in incarcerated populations but has not been specifically investigated in populations with psychiatric disorders. Electroencephalography research suggests increased alpha, theta and beta activity in frontal and posterior regions, some gamma band effects, with theta activity strongly related to level of experience of meditation; however, these findings have not been consistent. The few neuroimaging studies that have been conducted suggest volumetric and functional change in key brain regions. Conclusions:, Preliminary findings from treatment outcome studies provide support for the application of mindfulness-based interventions in the treatment of affective, anxiety and personality disorders. However, direct evidence for the effectiveness of mindfulness meditation per se in the treatment of psychiatric disorders is needed. Current neurophysiological and imaging research findings have identified neural changes in association with meditation and provide a potentially promising avenue for future research. [source] Three-dimensional study of the musculotendinous architecture of supraspinatus and its functional correlationsCLINICAL ANATOMY, Issue 6 2007Soo Y. Kim Abstract The supraspinatus is most frequently involved in shoulder pathology. However, the musculotendinous architecture of the supraspinatus has not been well documented. Therefore, the purpose of this study is to investigate the detailed three-dimensional architecture of the supraspinatus throughout its volume. Ten male formalin embalmed cadaveric specimens (mean age 61.9 ± 16 years) without any evidence of rotator cuff pathology were used. Three-dimensional coordinates (x, y, and z) of the tendon and muscle fiber bundles were collected in situ, using serial dissection and digitization. The data was reconstructed into a three-dimensional model using MayaÔ. Fiber bundle lengths, pennation angles (PA), muscle volumes, and tendon dimensions for each architecturally distinct area were computed and then analyzed using paired t -tests and ANOVA (P < 0.05). The supraspinatus was found to consist of anterior and posterior regions, which were each further subdivided into superficial, middle, and deep parts. Mean PA were found to be significantly different between the distinct parts of the anterior region of the muscle. Medial PA was also found be significantly different between the superficial and middle, and superficial and deep parts of the posterior region. These results provide insight into the normal function of the muscle and its possible contribution to the initiation and progression of supraspinatus tendon tears. Clin. Anat. 20:648,655, 2007. © 2007 Wiley-Liss, Inc. [source] Stability Measurements of Osseointegrated Implants Using Osstell in Partially Edentulous Jaws after 1 Year of Loading: A Pilot StudyCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 3 2002Piero Balleri MD ABSTRACT Background: The introduction of resonance frequency analysis (RFA) as a commercially available technique has made it possible to measure implant stability in implant stability quotient (ISQ) units at any time during the course of implant treatment and loading. However, no information on normal ISQ levels can be found in the literature. Purpose: The aim of this pilot study was to measure the stability of clinically successful implants in partially edentulous patients after 1 year of loading and to study the influence of jaw, anterior/posterior position, implant length, and marginal bone level on implant stability. Materials and Methods: Fourteen partially edentulous patients previously treated with 45 implants were subjected to clinical and radiographie evaluations and RFA measurements using Osstell (Integration Diagnostics, Sävedalen, Sweden) after 1 year of loading. Results: All 45 implants were stable, and implant stability levels were in the range of 57 to 82 ISQ units with a mean of 69 ± 6.5 ISQ after 1 year of loading. Mandibular implants were more stable than were maxillary ones. There were no differences between anterior and posterior implants. No correlation could be found between implant length and stability. Only minor marginal bone resorption was observed. Conclusions: The results from this limited material showed that successfully integrated implants have ISQ levels from 57 to 82 ISQ with a mean of 69 ISQ after 1 year of loading. Mandibular implants are more stable than are maxillary ones. High implant stability can be achieved with short implants and placement in posterior regions. [source] | |||||||||||||