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Maturation Arrest (maturation + arrest)
Selected AbstractsErythropoietin-induced, antibody-mediated pure red cell aplasia,EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 2005The Pure Red Cell Aplasia Global Scientific Advisory Board (GSAB) Abstract Pure red cell aplasia (PRCA) is a rare haematological condition that is characterized by severe aregenerative anaemia due to an almost complete cessation of red blood cell production. While antibody-mediated PRCA was extremely rare before 1998, the incidence of this disorder increased sharply after 1998 in patients receiving subcutaneous epoetin alfa produced by Ortho-Biotech and marketed outside the USA. The diagnosis of antibody-mediated PRCA relies mostly on the results of bone marrow biopsy or aspirate, which shows an absence of erythroid precursors and/or red cell maturation arrest while counts of white cell and platelet precursors are normal, and on the identification of circulating anti-erythropoietin antibodies. Retrospective analysis of PRCA cases has shown that immunosuppressive therapy can induce a disappearance of anti-erythropoietin antibodies in most patients. [source] cAMP response element modulator (CREM): an essential factor for spermatogenesis in primates?INTERNATIONAL JOURNAL OF ANDROLOGY, Issue 3 2001R. Behr CREM is a cAMP-related transcription factor and alternate promotor usage and splicing generate repressor and activator transcripts of CREM within the testis. CREM activators are highly expressed in post-meiotic haploid germ cells and are essential for spermatid maturation in the mouse model as revealed by gene-targeting studies. Analysis of testicular CREM expression in rodent and monkey species, and in men yielded a highly comparable pattern thus suggesting that CREM is of general importance for spermatid development in the mammalian testis. Also, many CREM target genes have been identified in haploid germ cells. Studies in men with spermatogenic disturbance and spermatid maturation arrest demonstrated abnormal CREM expression and altered splicing events. Collectively, the data strongly argue for an essential role of CREM during spermatid maturation in primates. [source] Role of transcription factors Ad4bp/SF-1 and DAX-1 in steroidogenesis and spermatogenesis in human testicular development and idiopathic azoospermiaINTERNATIONAL JOURNAL OF UROLOGY, Issue 6 2006YOSHIYUKI KOJIMA Background:, Ad4bp/SF-1 and DAX-1 are orphan members of the nuclear hormone receptor superfamily of transcription factors. In order to obtain better understandings of human testicular steroidogenesis and spermatogenesis, we examined the expression levels of both factors in human normal and idiopathic azoospermic testes and investigated their physical meaning. Methods:, First, we examined the expression level of Ad4bp/SF-1 and DAX-1 by quantitative reverse transcription,polymerase chain reaction (RT,PCR), immunohistochemistry and western blotting analysis using eight normal human testicular tissues from infants to adults. Second, we performed quantitative RT,PCR using testicular biopsy samples obtained from 22 idiopathic azoospermic patients to examine the expression of Ad4bp/SF-1 and DAX-1, and analysed the correlation between the expression levels of both factors and the serum hormone levels or histological evaluation to study their potential correlation with steroidogenesis and spermatogenesis on idiopathic azoospermia. Results:, The expression levels of both factors in the normal testes increased with testicular development. Ad4bp/SF-1 was abundantly expressed in Leydig cell, whereas DAX-1 was expressed in Sertoli cells. The expression level of Ad4bp/SF-1 in idiopathic azoospermic patients testes positively correlated with serum testosterone (P < 0.05). The average expression levels of DAX-1 mRNA for patients with maturation arrest (0.39 ± 0.19) and Sertoli cell-only syndrome (0.13 ± 0.08) were lower than that with hypospermatogenesis (1.60 ± 1.32) and normal spermatogenesis (1.30 ± 1.41). Conclusion:, Ad4bp/SF-1 is important for the maintenance of steroidogenesis in the human testis. DAX-1 plays a critical role in spermatogenesis in the human testis, and Sertoli cell-only syndrome and maturation arrest may result from abnormal Sertoli cell function that disrupts the normal progression of spermatogenesis. [source] Drug-associated histiocytoid Sweet's syndrome: a true neutrophilic maturation arrest variantJOURNAL OF CUTANEOUS PATHOLOGY, Issue 2 2008Angela J. Wu Histiocytoid Sweet's syndrome is a recently described entity which has clinical features identical to typical Sweet's syndrome but is distinguished by a dermal cellular infiltrate composed not of mature neutrophils but of immature granulocytes. Herein, we report a case of bone marrow granulocytic maturation arrest and a histological histiocytoid Sweet's-like reaction pattern following trimethoprim-sulfamethoxazole therapy. [source] ORIGINAL ARTICLE: The Role of IL-6, IL-10, TNF-, and its Receptors TNFR1 and TNFR2 in the Local Regulatory System of Normal and Impaired Human SpermatogenesisAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 1 2009gorzata Bia Problem, To investigate the expression of genes coding for selected cytokines with antagonistic functions (IL-6, IL-10, TNF-,) as well as TNF-, receptors (TNFR1 and TNFR2) in correct spermatogenesis (normal proliferation), maturation arrest (proliferation inhibited) and testicular tumors (overgrowth). Method of study, Transcription levels of genes coding for IL-6, IL-10, TNF-,, TNFR1 and TNFR2 were quantitatively examined using a real-time RT-PCR. Results, Significantly higher amounts of IL-6 mRNA were observed in testicular tumor samples than in normal spermatogenesis or in some syndromes with maturation arrest (MA at spermatid level or SCOS), while IL-10 gene levels were fairly stable. In homogenates with maturation arrest, the expression of TNFR1 gene was markedly higher than in testicular tumors, while the opposite phenomenon was found in respect to TNFR2 gene. Conclusion, The results obtained indicate that changes in activities of intra-testicular cytokines may promote different distinct pathologies such as testicular cancer or infertility. [source] SCF and c-kit expression profiles in male individuals with normal and impaired spermatogenesisANDROLOGIA, Issue 2 2010M. Bialas Summary The transcription levels of stem cell factor (SCF) and c-kit were examined using real-time RT PCR in interstitial and intratubular cell fractions, as well as in tissue homogenates from normal, azoospermic and neoplasmic patients. Peripheral blood mononuclear cells (PBMC) were used as a systemic control. The observed level of c-kit expression in all investigated groups was generally higher than the expression of SCF. The highest (statistically significant) level of c-kit was noted in testicular tumours (the greater part of which were represented by seminomas) in contrast to SCF mRNA, which may indicate an association between c-kit overexpression and seminoma development. In Sertoli cell only syndrome, almost equal levels of SCF and c-kit transcripts were noted. These results may indicate Leydig cells as the alternative source of c-kit gene transcription. SCF transcript values were low and comparable among the analysed subgroups except that in maturation arrest at spermatocyte stage, the SCF gene expression was statistically higher than in testicular tumours. It appears from the study that c-kit has been a dynamic gene, changing its activity in a variety of testicular pathologies while being expressed in all testicular compartments but clearly overexpressed in testicular tumours of seminomatous origin. [source] Low sperm recovery from the undescended testis with testicular sperm extraction in postpubertal cryptorchids: preliminary reportANDROLOGIA, Issue 2-3 2005H. C. Irkilata Summary As postpubertal cryptorchid testes are generally atrophic and have high malignancy risk, orchiectomy is recommended as the treatment method. However, a few case reports advocated orchiopexy due to finding sperm afterwards. The present clinical study aimed at determining the possibility of finding spermatozoa in postpubertal cryptorchid testis with testicular sperm extraction (TESE). Initially testicular biopsy and later TESE was performed in the undescended testis of 22 unilateral postpubertal cryptorchids and in one of the testes of three bilateral postpubertal cryptorchids. Histopathological assessment of testicular biopsy specimen showed that three patients had maturation arrest and 22 had seminiferous tubular atrophy. By TESE, spermatozoa were found in only one specimen of 25 testes. Our results show that the expectancy to find spermatozoa in postpubertal cryptorchid testis is extremely low by current sperm recovery methods and orchiectomy is still the accurate method of treatment. [source] Evaluation of the prognostic significance of Eosinophilia and Basophilia in a larger cohort of patients with myelodysplastic syndromesCANCER, Issue 10 2010Friedrich Wimazal MD Abstract BACKGROUND: Lineage involvement and maturation arrest are considered to have prognostic significance in patients with myelodysplastic syndromes (MDS). However, although the prognostic value of neutropenia, thrombocytopenia, and monocytosis have been documented, little is known about the impact of eosinophils and basophils. METHODS: The authors examined the prognostic significance of eosinophils and basophils in 1008 patients with de novo MDS. Patients were enrolled from 3 centers of the Austrian-German MDS Working Group and were analyzed retrospectively. Blood eosinophils and basophils were quantified by light microscopy, and their impact on survival and leukemia-free survival was calculated by using Cox regression. RESULTS: Eosinophilia (eosinophils >350/,L) and basophilia (basophils >250/,L) predicted a significantly reduced survival (P < .05) without having a significant impact on leukemia-free survival. In multivariate analysis, eosinophilia and basophilia were identified as lactate dehydrogenase (LDH)-independent prognostic variables with International Prognostic Scoring System (IPSS)-specific impact. Although elevated LDH was identified as a major prognostic determinant in IPSS low-risk, intermediate-1 risk, and high-risk subgroups, the condition "eosinophilia and/or basophilia" was identified as a superior prognostic indicator in the IPSS intermediate-2 risk subgroup. CONCLUSIONS: The evaluation of eosinophils and basophils in patients with MDS was helpful and may complement the spectrum of variables to optimize prognostication in MDS. Cancer 2010. © 2010 American Cancer Society. [source] | ||||||||||