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71.
F. Calabrese, M. Loy, F. Lunardi, D. Marino, S.M.L. Aversa, F. Rea. Acute cellular rejection and Epstein–Barr virus‐related post‐transplant lymphoproliferative disorder in a pediatric lung transplant with low viral load.
Transpl Infect Dis 2010: 12: 342–346. All rights reserved. Abstract: We report the case of an 18‐year‐old male who underwent bilateral lung transplantation for end‐stage cystic fibrosis. No Epstein–Barr virus (EBV) or cytomegalovirus serology mismatch was detected on pre‐transplant evaluation (donor and recipient were both positive). Two months after lung transplantation a computed tomography scan showed multiple nodules throughout both lungs. At that time a low EBV DNA blood level was detected (<300 copies/100,000 lymphomonocytes). Scheduled follow‐up transbronchial biopsy (TBB) revealed a prevalent finding characterized by perivascular lymphoid infiltrates with endothelitis. Extensive tissue coagulative necrosis with peripheral areas of dense aggregates of larger lymphoid cells were detected in the trans‐thoracic fine needle core biopsy (FNCB) performed on the largest nodule. The immunophenotypic profile characterized the perivascular lymphoid cells in TBB as mainly composed of T lymphocytes (CD3 positive) while the larger number of lymphocytes in FNCB as B cells (CD20 positive). In situ hybridization for EBV (EBER mRNA) was negative in TBB while it was positive in many lymphocytes of the FNCB. Real‐time polymerase chain reaction (PCR) for EBV was performed on paraffin‐embedded FNCB and detected a high quantity of EBV genomes (1260 copies/cell). IgH gene rearrangement using a fragment size PCR technique revealed a monoclonal B‐cell population in FNCB. Morphological and molecular findings suggest a final diagnosis of acute cellular rejection and a post‐transplant lymphoproliferative disorder (PTLD) EBV‐related in a lung transplant recipient with a low EBV DNA blood level. A possible coexistence of PTLD and acute rejection should be considered both for diagnosis and treatment. EBV PCR in the peripheral blood is a useful screening tool in transplant recipients; however, rare cases with PTLD may not have detectable levels of EBV DNA. This aspect should be taken into consideration to avoid false negatives.  相似文献   
72.
Abstract Little information is available concerning olfactory processing in frontotemporal lobar degeneration (FTLD). We undertook a case-control study of olfactory processing in three male patients fulfilling clinical criteria for FTLD. Odour identification (semantic analysis) and odour discrimination (perceptual analysis) were investigated using tests adapted from the University of Pennsylvania Smell Identification Test. General neuropsychometry and structural volumetric brain magnetic resonance imaging (MRI) were also performed. The three patients with FTLD exhibited a disorder of olfactory processing with the characteristics of a predominantly semantic (odour identification) deficit. This olfactory deficit was more prominent in patients with greater involvement of the temporal lobes on MRI. Central deficits of odour identification may be more common in FTLD than previously recognised, and these deficits may assist in clinical characterisation.  相似文献   
73.
Summary This report describes the case of a boy with prolidase deficiency who presented with splenomegaly and leg ulcers. Laboratory examination revealed hypergammaglobulinaemia, hyperimmunoglobulinaemia E, increased erythrocyte sedimentation rate, elevated transaminases, positive antinuclear and anti-double-stranded DNA antibodies, and complement consumption. No haematological, renal or articular problems were detected; neutrophil count was normal. The skin lesions were thought to be of vasculitic origin, and a diagnosis of systemic lupus erythematosus was made although the requirements for diagnosis of systemic lupus erythematosus based on American Rheumatism Association criteria were not satisfied. The child was treated with immunosuppressive drugs with worsening of skin lesions before the diagnosis of prolidase deficiency. Prolidase deficiency and systemic lupus erythematosus share a number of common immunological features and at least three patients with prolidase deficiency and immunological and clinical findings fulfilling the diagnostic criteria for systemic lupus erythematosus of the American Rheumatism Association are reported in the literature. Here we review pathogenetic hypothesis linking the metabolic defect to the disturbance in immune function. In particular we discuss the role of highly increased rates of apoptosis and/or abnormal processing of apoptotic keratinocytes in prolidase deficiency and the role of C1q deficiency, which is associated with the failure of normal clearance of apoptotic cells bearing on their surfaces many of the autoantigens involved in systemic lupus erythematosus. Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users. Online citation: JIMD Short Report #058 (2007) Online  相似文献   
74.
BACKGROUND: Amiodarone-induced thyrotoxicosis (AIT) may be caused by excessive thyroidal hormone synthesis and release (type 1) or by a destructive process (type 2). This differentiation is considered essential for therapeutic choice. PURPOSE: To evaluate the utility of color-flow Doppler sonography (CFDS) in the differential diagnosis and management of AIT. MATERIAL AND METHODS: The clinical and laboratory data, thyroid sonography (grayscale sonography [GSS], CFDS), thyroid radioiodine uptake (RAIU) and thyroid scintigraphy, treatment, and clinical outcome were retrospectively reviewed in 21 AIT patients. The CFDS pattern of thyroid nodules was separately described from that of the perinodular parenchyma, and AIT was classified as type 1 (increased blood flow) or type 2 (low/no blood flow). Type 1 AIT patients were treated with methimazole (alone or associated with potassium perchlorate), while type 2 patients were treated with prednisone or amiodarone withdrawal alone. RESULTS: Eleven patients with increased blood flow were considered as type 1, and 10 with low/no blood flow as type 2. Ten of the 11 patients in the first group showed a hypervascular nodular pattern, while one showed a hypervascular parenchymal pattern. Clinical diagnoses were toxic nodular goiter and Graves' disease, respectively. Of the 10 patients with low/no blood flow, six had normal thyroid volume, three small diffuse goiter, and one small multinodular goiter. The clinical outcome showed that 20 of the 21 patients were treatment responsive. CONCLUSION: CFDS is a useful tool in the differential diagnosis of AIT. This differentiation appeared to be of clinical relevance as regards therapeutic choice. Separate evaluation of parenchymal blood flow from that of nodules may prove beneficial in the diagnosis of underlying thyroid diseases in patients with type 1 AIT.  相似文献   
75.
Quick establishment of a confluent and stable endothelial cells (ECs) layer in the lumen of vascular grafts is critical for long-term patency of small-diameter vascular grafts. The objective of the study was to fabricate tubular nanofiber scaffolds, incorporate ECs onto the lumen of the scaffolds, and establish an animal model to prove the basic concept of using the scaffolds as vascular grafts. Poly(L-lactic acid)-co-poly(epsilon-caprolactone) P(LLA-CL 70:30) tubular nanofiber scaffolds were fabricated by electrospinning onto a rotating mandrel. Collagen was coated onto the scaffolds after air plasma treatment. Structure and mechanical property of the scaffolds were studied by scanning electron microscopy and tensile stress measurement, respectively. Human coronary artery endothelial cells (HCAECs) were rotationally seeded onto the lumen of the scaffolds at the speed of 6 rpm for 4 h through a customized seeding device, followed with static culture. Results showed evenly distributed and well-spread HCAECs throughout the lumen of the scaffold from 1 day onward to 10 days after seeding. Further, HCAECs maintained phenotypic expression of PECAM-1. To prove the basic concept of using the scaffolds as vascular grafts, acellular tubular P(LLA-CL) nanofiber scaffolds (inner diameter 1 mm) were implanted into rabbits to replace the inferior superficial epigastric veins. Results showed the scaffolds sustained the surgical process, kept the structure integrity, and showed the patency for 7 weeks.  相似文献   
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78.
Kinesin-5 inhibitors (K5I) are promising antimitotic cancer drug candidates. They cause prolonged mitotic arrest and death of cancer cells, but their full range of phenotypic effects in different cell types has been unclear. Using time-lapse microscopy of cancer and normal cell lines, we find that a novel K5I causes several different cancer and noncancer cell types to undergo prolonged arrest in monopolar mitosis. Subsequent events, however, differed greatly between cell types. Normal diploid cells mostly slipped from mitosis and arrested in tetraploid G(1), with little cell death. Several cancer cell lines died either during mitotic arrest or following slippage. Contrary to prevailing views, mitotic slippage was not required for death, and the duration of mitotic arrest correlated poorly with the probability of death in most cell lines. We also assayed drug reversibility and long-term responses after transient drug exposure in MCF7 breast cancer cells. Although many cells divided after drug washout during mitosis, this treatment resulted in lower survival compared with washout after spontaneous slippage likely due to chromosome segregation errors in the cells that divided. Our analysis shows that K5Is cause cancer-selective cell killing, provides important kinetic information for understanding clinical responses, and elucidates mechanisms of drug sensitivity versus resistance at the level of phenotype.  相似文献   
79.
OBJECTIVE: To assess histologically signs of testicular dysgenesis (TD) in the contralateral testes of patients with testicular germ cell tumours (GCTs) and to compare these findings with the spermatogenetic quality in healthy men, as the contralateral testis is considered to be involved with dysgenetic features such as poor sperm production, and accordingly, GCTs are hypothesized to be part of the 'TD syndrome' (TDS). One testicular biopsy is thought to represent spermatogenesis in the entire testis. We evaluated this view by using testicular two-site biopsies. PATIENTS AND METHODS: 2318 patients with testicular GCT had a contralateral testicular two-site biopsy. Testicular biopsies taken on forensic autopsy from 1388 presumably healthy men served as controls. Spermatogenesis was rated histologically according to a modified Johnsen score. Clinical factors were recorded to explore associations with reduced spermatogenesis. Differences in spermatogenesis scoring results among two-site biopsies were noted. Statistical analysis involved Wilcoxon-Mann-Whitney and Jonckheere-Terpstra tests for comparing patients and controls, and for studying associations with clinical factors. Classification and regression-tree analysis was used to explore multivariate associations. RESULTS: Histologically, patients had significantly poorer spermatogenesis than healthy men. Clinically, hypospermatogenesis was significantly associated with testicular atrophy, undescended testes, male infertility, and advanced clinical stage; 5.4% of cases (95% confidence interval 4.43-6.27) had discordant findings of >2 points on double biopsy and 9.8% had differences of 1 point. Discordance was significantly associated with poor spermatogenesis and testicular atrophy. CONCLUSIONS: We confirmed histologically that there is markedly reduced spermatogenesis in the contralateral testes of patients with GCT. This result lends credence to the view that GCT is part of the so-called TDS. But as hypospermatogenesis is associated with advanced clinical stage, impairment of sperm production might at least partly be acquired secondary to the endocrine activity of GCT. There were clinically relevant discordant results on double biopsy in 5.4%, predominantly in infertile patients and in atrophic testes. Thus the histological evaluation of male infertility is best done by multiple biopsies.  相似文献   
80.
Serum levels of YKL-40 have been associated with inflammatory diseases and breast cancer. Our purpose was to determine if YKL-40 in breast tissue, nipple aspirate fluid (NAF) and serum is (i) concentrated in NAF compared to matched serum, (ii) increased in the NAF, serum or tissue of women with biopsy proven precancer or cancer compared to healthy women and (iii) influenced by menopausal status. 118 women (61 healthy subjects, 10 with precancer and 47 with breast cancer) aged 17-95 years provided NAF with or without serum samples for analysis. Matched tissue was analyzed from a subset of subjects who underwent breast biopsy. All NAF and serum samples had detectable levels of YKL-40. Median YKL-40 levels for the entire cohort were 683 fold higher in NAF than serum. Premenopausal subjects had higher NAF and lower serum levels of YKL-40 than postmenopausal subjects. YKL-40 levels in NAF but not serum were higher in women with precancer (atypical hyperplasia and lobular carcinoma in situ) than in either healthy subjects (p = 0.025) or subjects with breast cancer (p = 0.015). In women with precancer, YKL-40 distribution in tissue correlated with YKL serum level (p = 0.043). YKL-40 is concentrated in NAF, with the highest concentrations in premenopausal women. NAF levels of YKL-40 are significantly higher in women with precancers than healthy subjects, suggesting that measuring YKL-40 in NAF may improve the identification of women at increased breast cancer risk.  相似文献   
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