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Biopsy Sampling (biopsy + sampling)
Selected AbstractsEfforts to develop methods for in vivo evaluation of the native ,-cell massDIABETES OBESITY & METABOLISM, Issue 2008S. Schneider Visualization and quantification of the native ,-cell mass in vivo in humans appear to be important in the study of the natural course of diabetes, and in ongoing trials aimed at preserving ,-cell mass in patients with diabetes. This cannot be done by biopsy sampling, and therefore there is a great need for development of a non-invasive method. This article discusses the principle theoretical requirements for reaching this goal. In addition, it provides an overview of tracer probes, which have been examined as potential ,-cell mass imaging agents in the past. Finally, some future perspectives are discussed. [source] The training stimulus experienced by the leg muscles during cycling in humansEXPERIMENTAL PHYSIOLOGY, Issue 6 2009Jamie S. McPhee Considerable variability exists between people in their health- and performance-related adaptations to conventional endurance training. We hypothesized that some of this variability might be due to differences in the training stimulus received by the working muscles. In 71 young sedentary women we observed large variations in the ratio of one-leg cycling muscle aerobic capacity to two-leg cycling whole-body maximal oxygen uptake (; Ratio1:2; range 0.58,0.96). The variability in Ratio1:2 was primarily due to differences between people in one-leg (r= 0.71, P < 0.0005) and was not related to two-leg (r= 0.15, P= 0.209). Magnetic resonance imaging (n= 30) and muscle biopsy sampling (n= 20) revealed that one-leg was mainly determined by muscle volume (r= 0.73, P < 0.0005) rather than muscle fibre type or oxidative capacity. A high one-leg was associated with favourable lipoprotein profiles (P= 0.033, n= 24) but this was not the case for two-leg . Calculations based on these data suggest that conventional two-leg exercise at 70% requires subjects with the lowest Ratio1:2 to work their legs at 60% of single-leg , whilst those with the highest Ratio1:2 work their legs at only 36% of maximum. It was concluded that endurance training carried out according to current guidelines will result in highly variable training stimuli for the leg muscles and variable magnitudes of adaptation. These conclusions have implications for the prescription of exercise to improve health and for investigations into the genetic basis of muscle adaptations. [source] Barrett's oesophagus,a pathologist's viewHISTOPATHOLOGY, Issue 1 2007J-F Fléjou Barrett's oesophagus, a precancerous condition for oesophageal adenocarcinoma, detected on endoscopy and confirmed on histology, shows intestinal metaplasia of the lower oesophagus. The significance of microscopic foci of intestinal metaplasia at the gastro,oesophageal junction, corresponding either to so-called ,ultrashort' segment Barrett's oesophagus, or to carditis with intestinal metaplasia, is still a matter of debate. The surveillance of patients with Barrett's oesophagus is still based on systematic biopsy sampling of Barrett's mucosa on endoscopy, looking for dysplasia. Although well-established classifications of dysplasia are now used by most pathologists, there remain numerous problems with this subjective marker (sampling, diagnostic reproducibility, natural history, etc). Therefore, many alternative biomarkers have been proposed, but only DNA aneuploidy, proliferation markers and p53 loss of heterozygosity/overexpression have been shown to be of some use at the present time. Some endoscopic improvements already allow a better selection of biopsies, and it may be that in future new technologies will allow ,virtual biopsies'. On the other hand, the role of pathologists now extends to the evaluation of new therapeutic modalities of early neoplastic lesions in Barrett's oesophagus, especially endoscopic mucosal resection. [source] Different structural components of conventional papillary thyroid carcinoma display mostly identical BRAF statusINTERNATIONAL JOURNAL OF CANCER, Issue 1 2007Alexander Abrosimov Abstract Activating BRAFT1799A mutation is closely associated with a papillary thyroid carcinoma (PTC) histotype. The transversion is frequently detected in the conventional type, Warthin-like and tall cell variants, but is rare in the follicular variant of PTC. Conventional PTC is often presented with tumors of mixed architecture, which besides the papillary structures also contain areas with follicular and solid morphology in which the details of BRAF mutational status are unknown. We set out to differentially investigate the presence of mutated BRAF in the individual structural components microdissected from 44 formalin-fixed, paraffin-embedded PTC tissues from 40 patients. The mutation was detected in at least 1 structural component in 23 tumors (52%). Different structural components of the same tumor had identical BRAF status in 41/44 tumors (93%). In 3 tumors the BRAFT1799A mutation was found only in the papillary, but not in the follicular component. Mutational patterns identical to those in the primary tumors were found in 11/12 lymph node metastases (92%, including both BRAFT1799A -positive and -negative cases). The high concordance of the BRAF mutational status in structurally distinct areas suggests a rather homogeneous distribution of neoplastic epithelial cells in a conventional PTC tumor in most cases. These results imply the reliability of preoperative molecular diagnosis of PTC regardless of the type of tumor component at the site of biopsy sampling and suggest that the majority of patients with BRAF mutation-positive PTC may benefit from the targeted pharmacotherapy. © 2006 Wiley-Liss, Inc. [source] Diagnostic Value of Endomyocardial Biopsy Guided by Electroanatomic Voltage Mapping in Arrhythmogenic Right Ventricular Cardiomyopathy/DysplasiaJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 11 2008ANDREA AVELLA M.D. Introduction: To improve the endomyocardial biopsy (EMB) diagnostic sensitivity for arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D), we hypothesized a biopsy sampling focused on selected right ventricle (RV) low-voltage areas identified by electroanatomic voltage mapping. Methods and Results: The study population (22 patients, 10 men; mean age 34 ± 10 years) included 11 patients with overt ARVC/D (group A) and 11 patients with suspected ARVC/D (group B), according to both arrhythmic profile and standardized noninvasive diagnostic criteria. In all 22 patients, an RV bipolar voltage mapping was performed with CARTOÔ system sampling multiple endocardial sites (262 ± 61), during sinus rhythm, with a 0.5,1.5 mV color range setting of voltage display. All 11 (100%) group A patients and 8 of the 11 (73%) group B patients (P = nonsignificant [NS]) presented RV low-voltage areas (<0.5 mV). In 8 group A patients and in all 8 group B patients with a pathological RV voltage map, an EMB focused on the low-voltage areas was performed. In 6 (75%) group A patients and in 7 (87%) group B patients (P = NS), voltage mapping-guided EMB was diagnostic for ARVC/D. In the remaining 3 patients, only nonspecific histological findings were observed. Conclusions: The results of our study (1) confirm the high diagnostic sensitivity of RV voltage mapping in patients with overt ARVC/D, (2) document a high prevalence of RV low-voltage areas even in patients with suspected ARVC/D, and (3) demonstrate that in patients with clinical evidence or suspicion for ARVC/D, presenting RV low-voltage areas, EMB guided by voltage mapping may provide ARVC/D diagnosis confirmation. [source] Current practice compared with the international guidelines: endoscopic surveillance of Barrett's esophagusJOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 5 2007Nassira Amamra MPH Abstract Rationale, aims and objectives, To describe the current practice for the surveillance of patients with Barrett's esophagus, to compare this practice with the national guidelines published by the French Society of Digestive Endoscopy in 1998 and to identify the factors associated with the compliance to guidelines. Method, To determine the attitudes of French hepatogastroenterologists to screening for Barrett's oesophagus, a postal anonymous questionnaire survey was undertaken. It was sent to 246 hepatogastroenterologists in the Rhone-Alpes area. We defined eight criteria allowed to assess the conformity of practices with the guidelines. We created three topics composed of several criterion. The topics analysed were ,Biopsies', ,Surveillance' and the diagnosis of high grade dysplasia. We studied the factors which could be associated with the compliance with the guidelines. Results, The response rate was 81.3%. For 58.0% of the gastroenterologists, endoscopic biopsy sampling were made according to French guidelines (four-quadrant biopsies at 2 cm intervals). Agreement was 78.0% regarding the interval of surveillance for no dysplasia (every 2 or 3 years) and 78.5% regarding the low-grade dysplasia (every 6 or 12 months). For the management of high-grade dysplasia, 28.6% actually confirm the diagnosis by a second anatomopathologist and 42.0% treated by proton pump inhibitor during 2 months. Concerning the biopsies, the young gastroenterologists and gastroenterologists practising in university hospitals had a better adherence to the guidelines (Relative Risk: 2.22, 95% CI 1.25,3.95 and 3.74, 95% CI 1.04,13.47, respectively). The other factors of risk were not statistically significant. Conclusions, The endoscopic follow-up is mostly realized in accordance with the national guidelines. However, there is a wide variability in individual current practice. [source] MR-guided biopsy of musculoskeletal lesions in a low-field systemJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 5 2001Claudius W. Koenig MD Abstract Thirty magnetic resonance (MR)-guided biopsies were obtained from 20 skeletal and 10 soft-tissue lesions in 31 patients using an open 0.2 T MR system equipped with interventional accessories. The results from aspiration (N = 3), core biopsy (N = 15), and transcortical trephine biopsy (N = 12) were evaluated for accuracy and clinical efficacy. Specimens were successfully obtained from 29 patients. Results were clinically effective in 23 patients, rated definitive in 16, nonconclusive in 9, and unspecific in 2 patients. A false diagnosis due to sampling error occurred in 2 patients, and biopsy sampling was impossible in one case. The best diagnostic yield was achieved from nontranscortical biopsies of osteolytic or soft-tissue masses. Results from transcortical biopsies were less specific due to the predominance of benign lesions. MR fluoroscopy for needle guidance was applied in 13 patients. Complete needle placement inside the magnet could be performed in 16 patients. MR-guided biopsy using an open low-field MR imager is feasible and clinically effective and will become a valuable tool in the management of musculoskeletal lesions. J. Magn. Reson. Imaging 2001;13:761,768. © 2001 Wiley-Liss, Inc. [source] Determining the sex of bottlenose dolphins from Doubtful Sound using dorsal fin photographsMARINE MAMMAL SCIENCE, Issue 1 2009Lucy E. Rowe Abstract Sexing cetaceans usually requires time-consuming observation, or genetic sexing via biopsy sampling or skin swabbing. We developed a method to determine the sex of bottlenose dolphins (Tursiops sp.) in Doubtful Sound, Fiordland, using laser-metric dorsal fin photographs. From dorsal fin photographs of 43 bottlenose dolphins of known sex (25 females, 18 males) we analyzed the shape, proportion of fin area covered in scarring and epidermal lesions, and the number of fin nicks. Males had significantly higher rates of scarring (P < 0.001) and dorsal fin nicks (P < 0.01) than females, whereas the severity of epidermal lesions was higher in females (P < 0.05). A logistic regression applied to all measured variables, and measurements of dorsal fin size, indicated that the proportion of dorsal fin scarring (P < 0.001), number of fin nicks (P < 0.01), and dorsal fin surface area (P < 0.01) were significant variables and together correctly predicted the sex of 93% (40/43) of the dolphins. The classification function may not be applicable to other populations due to geographic variation in bottlenose dolphin morphology and social structure. The method is quick and noninvasive to apply, and further increases the value of dorsal fin photo-identification pictures. [source] Time required to obtain endobronchial biopsies in children during fiberoptic bronchoscopyPEDIATRIC PULMONOLOGY, Issue 1 2009Nicolas Regamey MD Abstract Background Endobronchial biopsies are an important tool for the study of airway remodeling in children. We aimed to evaluate the impact of performing endobronchial biopsies as a part of fiberoptic bronchoscopy on the length of the procedure. Methods Clinically indicated fiberoptic bronchoscopy at which endobronchial biopsy was attempted as a part of a research protocol was performed in 40 children (median age 6 years, range 2 months,16 years). Time needed for airway inspection, bronchoalveolar lavage (BAL) with three aliquots of 1 ml/kg of 0.9% saline, sampling of three macroscopically adequate biopsies, teaching, and other interventions (e.g., removal of plugs) was recorded. The bronchoscopist was not aware that the procedure was being timed. Results Median (range) duration (min) was 2.5 (1.0,8.2) for airway inspection, 2.8 (1.7,9.4) for BAL, 5.3 (2.5,16.6) for biopsy sampling, 2.4 (1.5,6.6) for teaching and 4.1 (0.8,18.5) for other interventions. Three adequate biopsies were obtained in 33 (83%) children. Use of 2.0 mm biopsy forceps (via 4.0 and 4.9 mm bronchoscopes) rather than 1.0 mm (via 2.8 and 3.6 mm bronchoscopes) significantly reduced biopsy time (4.6 min vs. 8.4 min, P,<,0.001). Conclusions It takes a median of just over 5 min to obtain three endobronchial biopsies in children, which we consider an acceptable increase in the duration of fiberoptic bronchoscopy for the purpose of research. Pediatr Pulmonol. 2009; 44:76,79. © 2008 Wiley-Liss, Inc. [source] Effects of resistance training on cardiovascular responses to lower body negative pressure in the elderlyCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 5 2001Lynn B. Panton The purpose of the present study was to determine whether resistance training alters the cardiovascular responses to submaximal lower body negative pressure (LBNP) in the elderly. Twenty-one subjects were randomized into a control (C: n=10; 70 ± 3 years, mean ± SD) or a resistance training (TR: n=11; 67 ± 7 years) group. Subjects in the TR underwent 12 weeks of training consisting of three sets of 8,12 contractions at ,60,80% of their initial maximal one repetition, three times per week, on 10 different machines. Before (Pre) and after (Post) training, all subjects underwent exposures of LBNP of ,10, ,20 and ,40 Torr and muscle biopsy sampling at the vastus lateralis. TR increased (P,0·05) knee extension (Pre=379 ± 140 N, Post=534 ± 182 N) and chest press (Pre=349 ± 137 N, Post=480 ± 192 N) strength. Neither body weight nor percentage body fat were altered (P,>0·05) by training. Resistance training increased (P,0·05) cross-sectional area in both Type I (4203 ± 1196 to 5248 ± 1728 ,m2) and Type II (3375 ± 1027 to 4286 ± 1892 ,m2) muscle fibres. Forearm blood flow, forearm vascular conductance, mean arterial pressure, and heart-rate responses to LBNP were not altered by the training. These data suggest that the cardiovascular responses of elderly to LBNP are unaffected by 12 weeks of whole-body resistance training despite increases in muscle strength and size. [source] | |||||||||||||