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Selected AbstractsFine-needle aspiration of the testis in azoospermic men: The value of measuring serum follicle stimulating hormone and testicular sizeDIAGNOSTIC CYTOPATHOLOGY, Issue 4 2005W.A. Mourad M.D. Abstract Testicular fine-needle aspiration biopsy (FNAB) is used as a primary tool in assessing azoospermic infertile men in our institution. If the FNA is negative for sperm, a subsequent testicular biopsy specimen and wet preparation are obtained with possible immediate fertilization. To our knowledge, the value of these techniques in the context of testicular size and serum levels of follicle stimulating hormone (FSH) has not been explored. We reviewed 453 FNA biopsies of the testis performed for the identification of sperm in infertile azoospermic males between 1999 and 2000. We identified cases that had all three procedures (FNA, wet preparation and biopsy) performed. These were the patients that were compared for testicular size using Seager orchiometry and serum levels of FSH. Of the 453 FNAs reviewed, 128 (21%) had all three procedures performed. Seventy-two cases (56%) were negative in all three tests, 26 (20%) cases were positive in all tests, and 30 cases (23%) had different results. These 30 cases were excluded. The testicular size in the negative group ranged from 4 to 16 ml (median, 10 ml) and the positive group had testicular sizes ranging from 10 to 25 ml (median, 15 ml; P = 0.0001). The negative group had serum FSH levels ranging from 3 to 52 IU/l (median, 19 IU/l) whereas the positive group had serum levels ranging from 3 to 26 IU/l (median, 10 IU/l; P = 0.0001). Our findings suggest that in infertile azoospermic men, a testicular size of <10 ml combined with a serum FSH level of >19 IU/l, the chances of retrieving sperm are minimal using all three diagnostic modalities. The use of this cutoff point would lead to a 30,50% reduction in the number of procedures performed. This reduction would have a significant impact on the management of these patients with a significant decrease in cost, logistics, and patient anxiety. Diagn. Cytopathol. 2005;32:185,188. © 2005 Wiley-Liss, Inc. [source] Detailed Characterization of Contact Resistance, Gate-Bias-Dependent Field-Effect Mobility, and Short-Channel Effects with Microscale Elastomeric Single-Crystal Field-Effect TransistorsADVANCED FUNCTIONAL MATERIALS, Issue 5 2009Colin Reese Abstract The organic field-effect transistor (OFET) has proven itself invaluable as both the fundamental element in organic circuits and the primary tool for the characterization of novel organic electronic materials. Crucial to the success of the OFET in each of these venues is a working understanding of the device physics that manifest themselves in the form of electrical characteristics. As commercial applications shift to smaller device dimensions and structure/property relationships become more refined, the understanding of these phenomena become increasingly critical. Here, we employ high-performance, elastomeric, photolithographically patterned single-crystal field-effect transistors as tools for the characterization of short-channel effects and bias-dependent parasitic contact resistance and field-effect mobility. Redundant characterization of devices at multiple channel lengths under a single crystal allow the morphology-free analysis of these effects, which is carried out in the context of a device model previously reported. The data show remarkable consistency with our model, yielding fresh insight into each of these phenomena, as well as confirming the utility of our FET design. [source] Immunohistochemical characteristics of melanomaJOURNAL OF CUTANEOUS PATHOLOGY, Issue 5 2008Steven J. Ohsie Melanoma has a wide spectrum of histologic features which mimic epithelial, hematologic, mesenchymal, and neural tumors. Immunohistochemistry has been the primary tool to distinguish melanomas from these other tumors; it has also been studied for use as an adjunct to distinguish benign and malignant melanocytic tumors and to elucidate prognosis. Furthermore, there has been extensive effort to find a suitable marker to differentiate spindle cell and desmoplastic melanoma from other tumors. We have reviewed the literature investigating melanocytic differentiation markers, proliferation markers, immunomodulatory markers, signaling molecules, and nerve growth factors and receptors. Despite the proliferation of immunohistochemical markers, S-100 remains the most sensitive marker for melanocytic lesions, while markers such as HMB-45, MART-1/Melan-A, tyrosinase, and MITF demonstrate relatively good specificity but not as good sensitivity as S-100. No marker has proven useful in distinguishing spindle cell and desmoplastic melanomas from other tumors. Ki67 remains the most useful adjunct in distinguishing benign from malignant melanocytic tumors. None of the markers reviewed has been shown conclusively to have prognostic value for melanocytic neoplasms. [source] Ecoregional planning in marine environments: identifying priority sites for conservation in the northern Gulf of MexicoAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 4 2001Michael W. Beck Abstract 1.,The overall aim of this work was to identify sites within the northern Gulf of Mexico that, if protected, would fully represent the biological diversity of the nearshore waters of this ecoregion. In this paper, we focus on the eastern subregion, northwest Florida, to illustrate the process of ecoregional planning in marine environments. 2.,The basic steps in ecoregional planning include: identification of conservation targets, i.e. species and habitats; collection of data on their ecology and distribution; determination of conservation goals for the amount of targets that must be protected; and identification of a set of sites that meets these goals for all targets. 3.,As a preliminary goal, it was determined that the set of priority sites should contain at least 20% of the current distribution of each target habitat and species. 4.,Two primary tools were used to choose a set of priority sites: a reserve selection program, SITES, and interviews and a workshop with scientists and managers. The final set of priority sites integrated information from these various sources. 5.,The goals were exceeded for all conservation targets in the priority sites. On average, 75 and 58% of the distributions of the habitat targets were contained within the priority and high priority sites, respectively. These priority and high priority sites only occupied 29 and 17% of the study area, respectively. 6.,One of the first steps in the conservation of the bays identified as priority sites is the recognition that they are integrally linked by important processes to the surrounding terrestrial and aquatic environments. Conservation in a part of these estuarine landscapes will benefit biodiversity across environments. Copyright © 2001 John Wiley & Sons, Ltd. [source] | ||||||||||