Follistatin and activin A production by the male reproductive tract

Follistatin is a binding protein for the activin and inhibin family of hormones, regulating their biological activity. In the male reproductive tract, the interaction of these factors is likely to be involved in the regulation of the proliferation of several cell types. We have investigated the presence of follistatin and activin A in seminal plasma using specific immunoassays and have localized follistatin and activin/inhibin subunits in the adult human testis, prostate and seminal vesicle to establish their likely sources. High concentrations of immunoreactive follistatin were present in seminal plasma in normal men (mean 97.9 ng/ml; 1.43 ng/ml in peripheral plasma) and were similar in men with oligo/azoospermia and following vasectomy. Follistatin immunoreactivity was localized to both Leydig and Sertoli cells of the testis, and to epithelial cells of the prostate gland and seminal vesicle, which are likely to be the predominant sources of the hormone in seminal plasma. Activin A was also present in seminal plasma in normal men but was undetectable following vasectomy, thus deriving from the testis. Consistent with this finding, the betaA-subunit was immunolocalized in Sertoli and Leydig cells but was not present in seminal vesicle or prostate gland. The functional significance of the high concentrations of follistatin secreted into seminal plasma by the prostate gland and/or seminal vesicle is uncertain, but they may regulate the biological activity of testis-derived activin A and inhibin B.      

Protective cytotoxic T lymphocyte responses against paramyxoviruses induced by epitope-based DNA vaccines: involvement of IFN-gamma

Plasmid DNA vectors have been constructed with minigenes encoding a single cytotoxic T lymphocyte (CTL) epitope from either the M2 protein of respiratory syncytial virus (RSV) or from the nucleoprotein of measles virus (MV) with or without a signal sequence (also called secretory or leader sequence). Following intradermal immunization, plasmids in which the CTL epitopes were expressed in-frame with the signal sequence were more effective at inducing peptide- and virus- specific CTL responses than plasmids expressing CTL epitopes without the signal sequence. This immunization resulted in protection against MV-induced encephalitis and a significant reduction in viral load following RSV challenge. The reduction of viral load following RSV challenge was abrogated by prior injection with anti-IFN-gamma antibodies. These results highlight the ability of epitope-based DNA immunization to induce protective immune responses to well-defined epitopes and indicate the potential of this approach for the development of vaccines against infectious diseases.      

Y chromosome microdeletions, in azoospermic or near-azoospermic subjects, are located in the AZFc (DAZ) subregion

Submicroscopic deletions of the Y chromosome and polymorphisms of the androgen receptor (AR) gene in the X chromosome have been observed in men with defective spermatogenesis. To further define the subregions/genes in the Y chromosome causing male infertility and its relationship to polymorphisms of the AR polyglutamine tract, we screened the genomic DNA of 202 subfertile males and 101 healthy fertile controls of predominantly Chinese ethnic origin. Y microdeletions were examined with 16 sequence-tagged site (STS) probes, including the RBM and DAZ genes, spanning the AZFb and AZFc subregions of Yq11, and related to the size of trinucleotide repeat encoding the AR polyglutamine tract. Y microdeletions were detected and confirmed in three out of 44 (6.8%) of azoospermic and three out of 86 (3.5%) severely oligozoospermic patients. No deletions were detected in any of the patients with sperm counts of >0.5 x 10(6)/ml, nor in any of the 101 fertile controls. All six affected patients had almost contiguous Y microdeletions spanning the entire AZFc region including the DAZ gene. The AZFb region, containing the RBM1 gene, was intact in five of the six subjects. Y deletions were not found in those with long AR polyglutamine tracts. Our study, the first in a Chinese population, suggest a cause and effect relationship between Y microdeletions in the AZFc region (possibly DAZ), and azoospermia or near-azoospermia. Y microdeletions and long AR polyglutamine tracts appear to be independent contributors to male infertility.      

DNA fingerprinting of Ascochyta rabiei with synthetic oligodeoxynucleotides

Summary The ascomycete fungus Ascochyta rabiei, an important pathogen of the grain legume crop chickpea (Cicer arietinum L.) in the Mediterranean region, has not been adequately characterized in molecular terms. We therefore used DNA fingerprinting, with synthetic oligodeoxynucleotides complementary to simple repetitive sequences, to pathotype different isolates of the fungus. Six single-spored A. rabiei isolates were first categorized using a host differential set of nine chickpea genotypes. Seedlings were inoculated under controlled environmental conditions, and disease severity was recorded 9 days after inoculation. DNA was extracted from in vitro-grown mycelia of the six purified fungal isolates, restricted with EcoRI, HinfI, MboII and TaqI, and fingerprinted with radiolabeled (GATA)₄, (GTG)₅, (CA)₈, and (TCC)₅, respectively. High levels of polymorphism were detected with optimal enzyme/probe combinations that allow one to discriminate between the isolates. The potential of DNA fingerprinting with simple repetitive sequences can thus be expanded to the identification of fungal races and pathotypes. The characterization of the geographic distribution and genetic variability of pathotypes will facilitate the selection of suitable host cultivars to be grown in specific regions.     

Renal Transplantation: Experience at a Single Centre

Background

Renal transplantation program in the Armed Forces commenced in Feb 1991 and till date 245 patients have undergone renal transplantation at INHS Asvini. We describe our protocols for donor and recipient evaluation and immunosuppression. Methods: 245 patients received renal transplants during this period, 243 (99.2%) being from live donors. Most of them were started on triple immunosuppression comprising of cyclosporine, azathioprine and prednisolone. Newer drugs like mycophenolate, tacrolimus and sirolimus were administered in a select population.

Result

69 (28.1%) of them had at least one episode of acute rejection, most of which were steroid responsive and 13 (18.8%) of them required either anti CD3 monoclonal or anti-thymocyte globulin (ATG). Complete recovery with normal renal function occurred in 54 (78.2%) cases and 15 (21.7%) recovered with residual dysfunction with maximum serum creatinine being 2.1mg/dl. There were three (1.2%) cases of accelerated rejection during the first week of transplantation and one had graft rupture. All three lost their grafts. There were eight (3.2%) cases of acute tubular necrosis, who recovered completely within 8–14 days. Immediate infections included wound sepsis, lower respiratory tract infection, disseminated candidiasis and disseminated aspergillosis. Late infections included pulmonary tuberculosis, disseminated tuberculosis, cytomegalovirus infection and recurrent urinary tract infection. 28 (11.4%) patients developed post transplant diabetes mellitus. At the end of one year and five years, graft and patient survival were 97.2%, 93%, 80.9% and 85.7% respectively.

Conclusion

Our outcomes show that the transplantation is a viable mode of renal replacement therapy in patients of end stage kidney disease with a near normal rehabilitation.Key Words: Kidney, Transplantation, Immunosuppression, Complications     

Pulmonary homograft: should it be used in the aortic position?

OBJECTIVE: Retrospective analysis was performed to determine the suitability of pulmonary homograft as an aortic valve substitute. METHODS: From January 1994 through June 1999, 147 patients (mean age, 32.2 +/- 17.3 years) underwent aortic valve replacement with either an aortic homograft (group 1: n = 103, 25 fresh antibiotic preserved and 78 cryopreserved) or a pulmonary homograft (group 2: n = 44, 11 antibiotic preserved and 33 cryopreserved). In group 1 a scalloped subcoronary technique was used in 64 patients, and a root replacement technique was used in 39 patients. In group 2 the scalloped subcoronary technique was used in 34 patients, and the root replacement technique was used in 10 patients. RESULTS: There were 131 operative survivors (group 1 = 91; group 2 = 40). Follow-up ranged from 2 to 62 months. In group 1 none of the patients had significant aortic regurgitation during the hospital stay. Three patients (all having undergone the scalloped subcoronary technique) had moderate aortic regurgitation after 6 to 32 months. In group 2, 10 patients (9 having undergone the scalloped subcoronary technique and 1 having undergone the root replacement technique) developed significant regurgitation: 2 intraoperatively, 5 in the early postoperative period before discharge from the hospital, and 3 during late follow-up 6 to 12 months postoperatively. Among the various risk factors analyzed for overall homograft failure, use of a pulmonary homograft was the single independent predictor of valve failure (odds ratio, 8.6; 95% confidence interval, 1.9-39; P =.006). CONCLUSION: Pulmonary homograft, when inserted by means of a scalloped subcoronary technique, is not a suitable aortic valve substitute.     

The effect of foot orthoses on patellofemoral pain syndrome

In a retrospective review of 102 patients treated for chondromalacia pa-tellae and patellofemoral pain syndrome/retropatellar dysplasia (PFPS/RPD), the effectiveness of semiflexible foot orthoses was investigated. The combined disorders were diagnosed in 89.3% of the patients. Subjects were 46 women and 54 men, aged 12 to 87 years (mean, 37.9 years; SD, 15.9), who exhibited excessive forefoot varus or rearfoot varus. The initial screening and clinical diagnosis were based on an examination by an orthopedist. Particular attention was directed to patellar crepitation, patellofemoral malalignment, Q-angle measurements, limitation of range of motion, and knee effusion. Patients were evaluated for the onset and duration of patellofemoral pain and degree of knee joint disease. Semiflexible orthoses for each subject were fabricated, based on a clinical lower extremity biomechanical examination. At their follow-up visit, 76.5% were improved and 2% were asymptomatic, showing a significant decrease in the level of pain with orthoses intervention (chi-square P <.001). Although multiple treatment modalities are used for these patients, the results suggest that the use of semiflexible orthoses is significant in reducing symptoms of PFPS/RPD.