Spermatogonial kinetics in humans

The human spermatogonial compartment is essential for daily production of millions of sperm. Despite this crucial role, the molecular signature, kinetic behavior and regulation of human spermatogonia are poorly understood. Using human testis biopsies with normal spermatogenesis and by studying marker protein expression, we have identified for the first time different subpopulations of spermatogonia. MAGE-A4marks all spermatogonia, KITmarks all Bspermatogonia and UCLH1 all Apale-dark (Ap-d) spermatogonia. We suggest that at the start of the spermatogenic lineage there are Ap-d spermatogonia that are GFRA1High, likely including the spermatogonial stem cells. Next, UTF1 becomes expressed, cells become quiescent and GFRA1 expression decreases. Finally, GFRA1 expression is lost and subsequently cells differentiate into B spermatogonia, losing UTF1 and acquiring KIT expression. Strikingly, most human Ap-d spermatogonia are out of the cell cycle and even differentiating type B spermatogonial proliferation is restricted. A novel scheme for human spermatogonial development is proposed that will facilitate further research in this field, the understanding of cases of infertility and the development of methods to increase sperm output

[Seroepidemiologic studies in 63 patients given organ transplants in relation to cytomegalovirus, herpes simplex, varicella-zoster and HTLV-III: validity and limits].

We carried out a seroepidemiological study on 63 patients undergoing organ transplantation in order to determine viral markers like CMV, HTLV III, HS and V/Z. The antibodies valuation was carried out by enzyme-linked immunosorbent assays (ELISA-Abbott) and complement fixation test. All the tested markers give a high percentage of positivity even if the values relevant to anti-HTLV III antibodies can not be related to infection but, probably, to anti-HLA-Dr antibodies

Incidence of tumors in organ transplants.

0 RGAN transplantations have in the last years modified treatment of some diseases with bad outcome. However, regardless of the benefits of transplantation, some inconveniences have limited its success. Rejection, drug toxicity, or opportunistic infections together with neoplasm have been described occurring in these patients. In the past years, the occurrence of neoplasms has been quite rare; recently, however, their manifestations have consistently increased. We report the occurrence of neoplasms and their relative percentage in a group of 339 transplanted patients from the University of Rome “La Sapienza” between 1990 and 1995. The aim of our study was to estimate the relative occurrence of each neoplasm in our case population, the histologic subtype, the degree of differentiation, the site of involvement, disease-free survival from the date of transplant, and the type of neoplasm developed correlated to the organ transplanted and the drug administered

Alternative laparoscopic management of perforated peptic ulcers.

Surgery—namely, suture closure-is stili the treatment of choice for perforateci peptic ulcers, despite the proven efficacy of Taylor's conservative approach. Such conservative management, however, has been proven less effective in high-risk patients and those with perforations more than 12 h old. Here we suggest alternative laparoscopie treatments for perforated peptic ulcers. We have treated laparoscopically six patients (one F, five M; mean age 57.6 years; range 31—81 years); the mean duration of the operation was 52 min; the median hospital stay was 7 days (6-15 days); H2-blockers, antibiotics, and fluids were administered in the p.o. course; the follow-ups range from 6 to 18 months. On the basis of our experience, the treatment of choice for perforated peptic ulcers is Taylor's conservative procedure and laparoscopie drainage of the abdominal cavity when there is mild peritoneal reaction (usually less than 6 h from the onset of perforation). In case of remarkable peritonitis (usually more than 12 h), it is mandatory to add an accurate lavage. When the site of perforation is concealed by the peritoneal inflammation it should not be searched; when visible, it might be obliterated with the round ligament or an omental tissue strand

Alloantibodies and outcomes of deceased donor kidney allografts

Analysis of the anti-HLA antibody status of 100 recipients of kidneys from deceased donors demonstrated that presensitization and the development of alloantibodies after transplantation are associated with the development of antibody mediated as well as cellular rejection. This finding indicates that the humoral arm of the immune response is also involved in cell-mediated rejection and/or that there may be a continuum between these two forms of rejection. Most episodes of rejection were Successfully reversed in our population, as shown by the overall 3-year actuarial survival of 98% in nonsensitized and 91% in sensitized recipients, emphasizing the importance of comprehensive antibody studies. (C) 2009 American Society for Histocompatibility, and Immunogenetics. Published by Elsevier Inc. All rights reserved

Downregulation of recipient immunoresponsiveness to donor transplant antigens induced by CD8+CD28- and CD4+CD25+ cells

ERA-EDTA Downregulation of recipient immunoresponsiveness to donor transplant antigens induced by CD8, CD2, CD4, CD25, cells XLII Congresso ERA-EDTA. Istanbul, 4-7 giugno 2005

Evaluation of pretransplant immunologic status in kidney-transplant recipients by panel reactive antibody and soluble CD30 determinations.

Objectives. To retrospectively compare the accuracy of pretransplant panel of reactivity antibodies (PRA) and serum level of soluble CD30 (sCD30) in predicting early (6 months) acute rejection (AR) in living-donor and deceased-donor kidney-transplant (KT) patients. Methods. Pretransplant sera of 24 KT recipients were retrospectively tested for sCD30 and compared with PRA. Inclusion criteria were de novo graft patients on calcineurin–inhibitor-based immunosuppression, minimum follow-up of 1 year, alive with a functioning graft, and stable renal function over the last 12 months. Objective measures were incidence of biopsy-proven AR (BPAR) within 6 months of KT and sCD30 and PRA diagnostic indexes. The relative risk (RR) of BPAR for each test was also obtained. Results. Fourteen (58.3%) patients presented at least one episode of BPAR within 6 months of KT. All rejection episodes were responsive to steroid treatment. PRA was positive in six (25%) patients, and four (66.7%) of them presented at least one episode of BPAR. sCD30 tested positive in nine (37.5%) patients, and all these later presented at least one episode of BPAR. sCD30 and PRA diagnostic indexes in predicting early ( 6months) BPAR were sensitivity 64.2% versus 28.5%; specificity 100% versus 80%; accuracy 79.1% versus 50%; positive predictive value 100% versus 66.6%; and negative predictive value 66.6% versus 44.4%. The RR of early AR was 1.4 in PRA-positive patients and extremely higher in the sCD30-positive group. Conclusions. Pretransplant sCD30 is a more accurate predictor of AR when compared with PRA. These results support its use in the pretransplant work-up of kidney-graft recipients