Immunofluorescence staining in unfixed or fixed renal biopsy specimens from patients with diabetic nephropathy

Immunofluorescence staining in unfixed or fixed renal biopsy specimens were evaluated in nine patients with diabetic nephropathy in order to elucidate if immunofluorescence staining is applicable in fixed renal tissues in such patients. Renal biopsy specimens were embedded in gelatin or paraffin matrix. Renal biopsy specimens embedded in paraffin matrix were digested with 0.05% protease. Immunofluorescent studies of kidney tissues were performed by staining with FITC-labeled heavy chain specific anti-human IgG, IgA, IgM, acute phase reactant (APR) proteins such as alpha 1-anti-trypsin (alpha 1-AT), haptoglobin (Hpt) and beta-lipoprotein (beta-Lp) antisera, and then examined with a fluorescent microscope. Linear and nodular deposition of IgG, IgA, IgM, alpha 1-AT, Hpt, and beta-Lp were observed in the glomerular capillary walls of the renal specimens embedded in paraffin matrix. The staining patterns in specimens embedded in paraffin matrix was similar to that embedded in gelatin matrix. There was no significant difference in the intensity or distribution of IgG, IgM, alpha 1-AT, and beta-Lp deposition among the two different conditions of immunofluorescence in patients with diabetic nephropathy. It was suggested that immunofluorescence staining in renal biopsy specimens embedded in paraffin matrix after digestion with protease is useful for the evaluation of IgG, IgM, APR proteins, and beta-Lp in glomeruli from patients with diabetic nephropathy.     

Hyperosmolar solutions selectively block action potentials in rat myelinated sensory fibers: implications for diabetic neuropathy

Diabetic neuropathy is a common complication of diabetes mellitus patients. It is a wide range of abnormalities affecting proximal and distal peripheral sensory and motor nerves. Although plasma hyperosmolality is a common finding in diabetes mellitus, the effects of hyperosmolality on conduction of various sensory signal components have not been addressed in detail. Here we show that in rat dorsal root ganglion (DRG) preparations from normal rats, hyperosmolar solutions (360 mmol/kg, containing increased glucose, sucrose, NaCl, or mannitol) produce a selective block of signal propagation in myelinated sensory A-fibers. In compound action potential (CAP) recordings with suction electrodes, peak A-fiber CAP amplitude was selectively decreased (20%), while the C-fiber peak remained intact or was slightly increased. Hyperosmolar solutions had smaller effects on conduction velocity (CV) of both A- and C-fibers (approximately 5% decrease). Hyperosmolality-induced CAP changes could not be observed during recordings from isolated spinal nerves but were evident during recordings from desheathed spinal nerves. In intracellular recordings, hyperosmolar solutions produced a block of spinal nerve-evoked action potential invasion into the somata of some A-fiber neurons. Removal of extracellular calcium completely prevented the hyperosmolality-induced CAP decreases. Based on these data, we propose that the decreased CAP amplitudes recorded in human patients and in animal models of diabetes are in part due to the effects of hyperosmolality and would depend on the extracellular osmolality at the time of sensory testing. We also hypothesize that hyperosmolality may contribute to both the sensory abnormalities (paresthesias) and the chronic pain symptoms of diabetic neuropathy.     

Central review of bone marrow biopsy specimens from patients with neuroblastoma.

In order to achieve some uniformity in histological detection of bone marrow infiltration by neuroblastoma and to provide a measure of variation in histological opinions, sections from 712 evaluable trephine biopsy cores from children in a European Neuroblastoma Study Group (ENSG) study were reviewed centrally. Biopsy specimens were graded as tumour positive or negative. Discordance between local and central review opinions was found in 5% of specimens. Only five of 165 children at presentation and nine of 256 re-staging procedures in 126 children, affecting one child each, had their diagnosis upgraded to positive. In six re-staging procedures, affecting one child each, the diagnosis was downgraded. The low discordance rate is encouraging and substantially less important than previously documented difficulties in obtaining adequate specimens.     

Pathomorphological and immunohistochemical analysis biopsy specimens from large bronchi of patients with pulmonary cancer

Biopsy specimens from large bronchi of patients with central and peripheral pulmonary cancer were studied. Central cancer was associated with hyperplasia and dysplasia of the epithelium, hyperplasia of glandular compartment, and pronounced immunocompetent cell response. Peripheral cancer was characterized by predominance of atrophic and sclerotic changes, lymph flow disorders, and tendency to lymphoid aggregation. These data suggest that not only dysplasia, but also the combination of all structural changes typical of each form of pulmonary cancer should be considered as a morphological marker of enhanced risk of tumor development.     

Variability in hepatic iron concentration in percutaneous needle biopsy specimens from patients with transfusional hemosiderosis

In patients with sickle cell disease or beta-thalassemia receiving RBC transfusions for a long period, a precise knowledge of the liver iron concentration (LIC) is essential for treatment. Patients underwent LIC and liver pathology assessment by duplicate biopsies in 2 passes from the same local liver site. Fresh tissue cores in trace element-free containers and tissues from dissolved paraffin-embedded cores were analyzed. LIC measurements in each of 2 paraffin-embedded cores did not differ significantly (median, 12,455 vs 12,153 microg/g dry weight; n = 29). A significant difference was observed when 1 fresh tissue sample and 1 paraffin-embedded core were analyzed (median, 11,716 vs 12,864 microg/g dry weight; n = 16; P < .001) with a median disagreement between LIC measurements of 23.0%. We found high agreement in LICs between liver biopsy specimens processed by the paraffin-embedding technique but overestimation of LICs in comparison with desiccated fresh tissue samples.     

Sensory nerve area measurements in patients with diabetic neuropathy

Sensory nerve potential area measurements may reflect the properties of underlying nerve fibres better than amplitude or conduction velocity measures. The terminal segment of the sensory curve may contain activity of regenerating nerve fibres. The reliability of area measurements of sensory potentials obtained with surface recording techniques is unknown. We scanned sural nerve sensory potential curves and measured the areas under different parts of the curve in 52 reference and 73 diabetic polyneuropathy (DPN) patients. The variability of repeat testing in reference subjects for total area was 12% and for the terminal segmental area (TSA) was 19%. In DPN patients, the total area variability was 17% and TSA variability was 24%. This compares to amplitude variability of 8% in reference subjects and 10% in patients with DPN. These results demonstrate that sensory potential area measurements are feasible, but highly variable. We conclude that current clinical trials do not include sufficient numbers of patients to show change in area measurements, particularly the area under the terminal segment of the curve.     

Microneurographic findings of relevance to pain in patients with erythromelalgia and patients with diabetic neuropathy

Mechanisms responsible for neuropathic pain are still unclear. By using microneurography we have been able to record from single C-nociceptive and sympathetic fibers in patients and attempted to uncover possible abnormal functional properties of these fibers of relevance for pain. In two previously published studies conducted on patients with erythromelalgia and patients with diabetic neuropathy, some of the major findings were: (1) spontaneous activity in nociceptive fibers, (2) sensitization of mechano-insensitive C-fibers, and (3) an altered distribution of C-afferent nerve fibers with a reversal of the proportion of the two main subtypes of C-nociceptive fibers, indicating a loss of function of polymodal nociceptors. Although some degree of spontaneous activity and sensitization also was found in patients without pain, these mechanisms may still be of importance for the development and maintenance of neuropathic pain. A change in the distribution of C-nociceptive fibers in the skin as shown in the patients with diabetic neuropathy may help to reveal mechanisms responsible for small-fiber dysfunction.     

Depletion of neuroendocrine cells in rectal biopsy specimens from HIV positive patients.

AIMS: To compare the density of neuroendocrine cells in rectal biopsy specimens from human immunodeficiency virus (HIV) infected individuals with that of a control group. METHODS: Neuroendocrine cells in rectal biopsies were identified using an immunohistochemical stain for chromogranin and subsequently quantified using a method of linear intercept. RESULTS: Neuroendocrine cells were found to be significantly decreased in the HIV positive group. CONCLUSIONS: Loss of neuroendocrine cells may contribute to apoptotic bodies seen in this condition. This could be related to infection of these cells with HIV and could contribute to diarrhoeal disease in HIV infection.     

糖尿病性周围神经病患者的运动神经传导阻滞现象

目的：观察糖尿病性周围神经病（DPN）患者运动神经传导阻滞（CB）的发生率及其与其它神经电生理参数的关系。方法：对346例糖尿病患者的神经电生理检测数据，包括运动神经传导速度（MCV）、F反应、感觉神经传导速度（SCV）等作回顾性分析。并对MCV测定时近、远端刺激引出的复合肌肉动作电位（CMAP）波幅和波面积进行比较，判断是否存在CB。结果：①在346例糖尿病患者中，有CB的病例为57例占16.5％，受检的1345条神经中，有62条神经异常，占4.6％，胫神经异常率最高（13.6％）。②出现CB的患者受检的225条神经中，SCV、F反应、MCV的异常率依次为52.9％、47.4％和45.1％。③出现CB的神经有67.9％伴有F波潜伏期延长和/或F波传导速度减慢，32.1％出现F波时间离散度增加。结论：部分糖尿病患者存在运动神经传导阻滞现象（CB）、胫神经CB出现率最高；运动神经CB多伴有MCV其它参数异常。     

Vaginal adenosis. Analysis of 325 biopsy specimens from 100 patients.

Biopsy-proven vaginal adenosis was found in 88% of a group of 100 asymptomatic young women with known or suspected to have histories of intrautering diethylstilbestrol (DES) exposure. Histologic features were roughly quantitated and were found to vary markedly from patient to patient, but the following proved to be the most consistent features: (1) variation in glandular configuration (simple, complex, cystic); (2) the presence of epithelium recapitulating all parts of the müllerian duct system (endocervical, endometrial and tubal); (3) limited involvement of the vaginal mucosa (no surface involvemtn in 23.8% of the patients); (4) extensive squamous metaplasia; (5) submucosal inflammation. There was no glandular dysplasia or coexistent adenocarcinoma. The squamous epithelium in many specimens contained little or no glycogen, and in some manifested cellular activity consistent with a regenerative response to inflammation. Sufficient atypicality to implicate vaginal adenosis as a premalignant lesion was not found in any biopsy specimen.     

糖尿病性周围神经病的定量感觉检查

目的:探讨定量感觉检查(QST)对糖尿病性周围神经病(DPN)诊断的临床应用价值.方法:应用QST仪检测118名正常人与136例DPN病人的冷觉(CS)、热觉(WS)和振动觉(VS)阈值及神经传导速度(NCV).结果:DPN组和单纯糖尿病(DM)组与正常对照组比较,手指和足背QST的CS、WS、VS阈值差异均有统计学意义(P＜0.05).DPN组和单纯DM组之间比较,手指和足背CS、WS、VS阈值差异也有统计学意义(P＜0.05).DPN组和单纯DM组之间比较手指和足背不同部位的CS、WS、VS阈值差异均有显著意义(P＜0.05).DPN组CS、WS、VS的异常率高于运动神经传导速度(MCV)、感觉神经传导速度(SCV)的异常率(P＜0.05),CS、WS的异常率高于VS的异常率(P＜0.05);DPN组患者的MCV、SCV、CS、WS和VS异常率均高于单纯DM组的异常率,其间差异有显著意义(P＜0.01);病程＞5年组的MCV、SCV、CS、WS和VS的异常率均高于病程≤5年组的异常率,其间差异亦有显著意义(P＜0.01);HbAlC正常组和HbAlC异常组MCV、SCV、CS、WS和VS异常率之间比较差异均无统计学意义(P＞0.05).结论:QST能为DPN的早期诊断提供可靠依据,是常规NCV检查的必要补充.     

Skin biopsy as a beneficial procedure for morphological evaluation of diabetic neuropathy

In an attempt to evaluate the morphological abnormalities of dermal non-myelinated nerve fibers of diabetics and elucidate the pathogenesis of diabetic peripheral neuropathy, the terminal part of peripheral nerve in the upper dermis was observed on electron microscopy using skin samples biopsied in 10 diabetics with symptomatic neuropathy and 6 age-matched controls. In diabetics, the density of nerve fibers was significantly lower than in controls. In addition, swelling, lytic change and vacuolation in the axon, multiplication of basement membrane of the Schwann cell and Schwann cell cluster devoid of axon were more frequently observed in diabetics. The Schwann cell did not show significant structural alterations. These findings suggest that the axon is primarily involved, at least in the terminal region of nerve fiber, in diabetic peripheral neuropathy. It is also concluded that the skin biopsy technique is harmless, cosmetically not troublesome and might be beneficial for studying peripheral neuropathies including diabetic neuropathy.     

Hereditary motor and sensory neuropathy with deafness,mental retardation,and absence of sensory large myelinated fibers: Confirmation of a new entity

We describe two brothers, 11 and 13 years old, respectively, with an early-onset hereditary motor and sensory neuropathy, deafness, and mental retardation. Electrophysiological studies showed marked reduction of motor and sensory conduction velocity and absence of sensory action potentials. Sural nerve biopsy, performed in both patients, showed absence of large myelinated fibers with normal density of small myelinated fibers without axonal degeneration. Signs of demyelination were found only in the younger patient. We suggest that motorsensory neuropathy associated with deafness and mental retardation with absence of large myelinated fibers on sural nerve biopsy represents a distinct clinicopathological entity, which is transmitted in families probably as an autosomal recessive trait. Am. J. Med. Genet. 75:309–313, 1998. © 1998 Wiley-Liss, Inc.     

Decreased vasoactive intestinal polypeptide (VIP) level in cerebrospinal fluid from diabetic patients with neuropathy

The concentration of vasoactive intestinal polypeptide (VIP) was measured in cerebrospinal fluid (CSF) obtained from diabetic patients with neuropathy and their age-matched control subjects. VIP level in CSF from diabetic patients was significantly decreased as compared with that from the controls (12.9 +/- 3.1 pg/ml vs. 35.4 +/- 3.3 pg/ml, p less than 0.01). Decreased VIP level in CSF may relate with diabetic neuropathy in particular sexual dysfunction.     

Quantification of collagen and elastic fibers using whole‐slide images of liver biopsy specimens

Histological evaluation of fibrosis after a liver biopsy is crucial for evaluating the pathology of patients with chronic liver disease. Previous studies have reported quantitative analyses of fibrosis using images of collagen‐stained sections. However, analysis of these studies requires manual selection of the region of interest. In addition, the quantification of elastic fibers is not considered. The present study was conducted in order to measure both the collagen and elastic fiber area ratios using Elastica van Gieson‐stained whole‐slide images (WSIs) of liver biopsy specimens. High‐resolution WSIs provide precise color classification, enabling accurate detection of even fine collagen and elastic fibers. To minimize the influence of pre‐existing fibrous tissue, median area ratios of the collagen and elastic fibers were independently calculated from the image tiles of the WSIs. These median area ratios were highly concordant with area ratios after the pre‐existing fibrous tissues were manually trimmed from the WSI. Further, these median area ratios were correlated with liver stiffness as measured by transient elastography (collagen: r = 0.73 [P < 0.01], elastic: r = 0.53 [P < 0.01]). Our approach to quantifying liver fibrosis will serve as an effective tool to evaluate liver diseases in routine practice.