Mouse homologues of the human AZF candidate gene RBM are expressed in spermatogonia and spermatids, and map to a Y chromosome deletion interval associated with a high incidence of sperm abnormalities

An RNA-binding motif (RBM) gene family has been identified on the human Y chromosome that maps to the same deletion interval as the 'azoospermia factor' (AZF). We have identified the homologous gene family (Rbm) on the mouse Y with a view to investigating the proposal that this gene family plays a role in spermatogenesis. At least 25 and probably >50 copies of Rbm are present on the mouse Y chromosome short arm located between Sry and the centromere. As in the human, a role in spermatogenesis is indicated by a germ cell-specific pattern of expression in the testis, but there are distinct differences in the pattern of expression between the two species. Mice carrying the deletion Yd1, that maps to the proximal Y short arm, are female due to a position effect resulting in non-expression of Sry ; sex-reversing such mice with an Sry transgene produces males with a high incidence of abnormal sperm, making this the third deletion interval on the mouse Y that affects some aspect of spermatogenesis. Most of the copies of Rbm map to this deletion interval, and the Yd1males have markedly reduced Rbm expression, suggesting that RBM deficiency may be responsible for, or contribute to, the abnormal sperm development. In man, deletion of the functional copies of RBM is associated with meiotic arrest rather than sperm anomalies; however, the different effects of deletion are consistent with the differences in expression between the two species.      

Blue rubber bleb nevus syndrome and pulmonary hypertension: an unusual association

INTRODUCTION: Blue rubber bleb nevus syndrome (BRBNS) is a rare congenital systemic angiodysplasia with multiple vascular malformations in the skin, gastrointestinal tract and, less often, in other internal organs and the brain. CASE REPORT: A 36-year-old man with past history of BRBNS was admitted to our hospital for progressive dyspnea and fatigue. Primary pulmonary hypertension (PPH) was diagnosed. He then developed acute abdominal pain and dyspnea, dying in a few hours due to sudden cardiac arrest. Postmortem examination demonstrated angiomatous lesions located in the skin, small bowel, heart, lungs, liver and thyroid. The lesions were slightly raised, soft and compressible and microscopically consisted of dilated vascular channels lined by a flattened endothelium. The vascular wall was formed by several layers of smooth muscle cells, intermixed with abundant aggregates of elastic lamellae and thin collagen fibers. Luminal thrombi were a frequent finding. In the small bowel, we identified the presence of an abnormally large artery directly opening into a thin-walled venous channel. The most striking finding in the lungs was the presence of thrombi of varying age in the lumen of segmental and elastic arteries, as well as muscular arteries and arterioles. Severe medial hypertrophy of muscular arteries and muscolarization of arterioles were also present. Intimal proliferative lesions and plexiform lesions were never observed. CONCLUSION: The pulmonary findings are consistent with recurrent thromboembolic events from shunts in the visceral lesions. To our knowledge, this is the first report of BRBNS with visceral arterovenous (AV) fistulae complicated by thromboembolic pulmonary hypertension (PH).     

Burkitt's lymphoma: new insights into molecular pathogenesis

The World Health Organisation classification reports three subcategories of Burkitt's lymphoma (BL)--endemic, non-endemic, and immunodeficiency associated--proposed to reflect the major clinical and genetic subtypes of this disease. These different types of BL have been reviewed and studied by immunohistochemistry and molecular methods. The results point out the heterogeneity of BL and suggest that AIDS related BL may have a different pathogenesis from that of classic BL.     

Comparison of once-daily atazanavir with efavirenz, each in combination with fixed-dose zidovudine and lamivudine, as initial therapy for patients infected with HIV

BACKGROUND: Atazanavir, an azapeptide protease inhibitor (PI), has pharmacokinetics that allow once-daily dosing, and it is not associated with significant PI-associated dyslipidemia. METHODS: A randomized, double-blind, double-dummy, active-controlled, 2-arm study comparing the antiviral efficacy and safety of atazanavir 400 mg administered once daily with efavirenz 600 mg administered once daily in combination with open-label fixed-dose zidovudine plus lamivudine twice daily. The 810 treatment-naive patients were stratified by HIV RNA level. The primary efficacy end point was the proportion of treated patients with HIV RNA levels <400 copies/mL through week 48. RESULTS: At week 48, HIV RNA levels were <400 copies/mL in 70% of patients receiving atazanavir and 64% of patients receiving efavirenz (intent-to-treat, difference; 95% confidence interval: 5.2%; -1.2%, 11.7%). Median CD4 cell counts increased at comparable magnitudes and rates in the 2 treatment arms (mean change at week 48: 176 cells/mm with atazanavir, 160 cells/mm with efavirenz). Atazanavir-treated patients relative to comparator-treated patients did not demonstrate significant increases in total cholesterol, fasting low-density lipoprotein cholesterol, or fasting triglycerides over 48 weeks of therapy. Atazanavir-linked bilirubin elevations infrequently resulted in treatment discontinuation (<1%). Atazanavir treatment did not increase fasting glucose or insulin levels. CONCLUSIONS: For initial HIV treatment, a highly active antiretroviral therapy regimen of atazanavir/zidovudine/lamivudine is as efficacious and well tolerated as the combination of efavirenz/zidovudine/lamivudine.     

High-degree abnormalities of nuclear DNA distribution in SIg negative acute lymphoblastic leukemia with vacuolated blasts

Among 65 consecutive patients with untreated adult acute lymphoblastic leukemia (ALL), six had peculiar clinical and cytologic features. Bone marrow and circulating blasts were large and showed prominent vacuolization, with variable degree of granular periodic acid-Schiff positivity in the cytoplasm. All patients had marked spleen and liver enlargement with cholestasis and without either lymph node or central nervous system disease. They achieved complete response to chemotherapy, and their median survival was longer than 12 months. Blast cells were studied for immunologic markers, propidium iodide flow cytofluorometric DNA content, and in vitro tritiated thymidine labeling index (3H-TdR LI). These showed a "null" phenotype in two cases, contained intracytoplasmic immunoglobulins (Cy mu) in two and were positive for CALL and Ia antigens in two others (one of which also contained Cy mu). Surface immunoglobulins (SIg) were found on less than 12% of cells, and T-cell markers were absent. In five cases, one or two stem lines with highly abnormal modal DNA content were found to coexist with diploid blasts. The 3H-TdR LI was high (8.5%-15.5%). Abnormal cell lines, after being cleared by chemotherapy, were found again at relapse. Additional cell lines appeared during the course of the disease in one patient, having different sensitivity to cytostatics. These cases of ALL apparently derive from B-cells not yet expressing SIg and have an exceptionally high incidence of aneuploid cell lines.     

Zoledronic acid-related angiogenesis modifications and survival in advanced breast cancer patients.

The proven antiangiogenic activity of zoledronic acid, a third-generation bisphosphonate widely used in bone metastatic cancer patients, led us to investigate if the vascular endothelial growth factor (VEGF)-related zoledronic acid modifications are correlated with survival advantages in advanced breast cancer patients. Forty-two consecutive breast cancer patients with scintigraphic and radiographic evidence of bone metastases were treated with a single infusion of 4 mg zoledronic acid before anticancer chemotherapy. The patients were prospectively evaluated for circulating levels of VEGF and interferon-gamma (IFN-gamma) just before and at 1, 2, 7, and 21 days after zoledronic acid infusion. Afterward, clinical outcome was prospectively monitored. The basal serum VEGF median levels were significantly decreased at each time point, but the major reduction was recorded 21 days after the infusion. In particular, 25 patients of 42 (59.5%) experienced a reduction of at least 25% in the VEGF circulating levels. In contrast, no statistically significant modifications of the IFN-gamma serum levels were recorded. We stratified patients on the basis of this VEGF reduction 21 days after the infusion. No differences in patient features were recorded between those with or without the VEGF reduction. The analysis of survival showed that patients with a reduction in the VEGF circulating levels had a longer time to first skeletal-related event (p = 0.0002), time to bone progression disease (p = 0.0024), and time to performance status worsening (p = 0.0352) than those without the VEGF reduction. No statistically significant differences were recorded in terms of overall survival and time to visceral progression. This study confirms that zoledronic acid could have an in vivo antiangiogenic property and that the VEGF modifications may represent a surrogate marker able to predict time to first skeletal-related event, time to bone progression disease, and time to worsening of performance status.     

Therapeutic apheresis in children: experience in a pediatric dialysis center

The use of apheretic procedures in pediatric patients has always been restricted by technical difficulties and the low incidence of diseases requiring this kind of treatment. The aim of the present study was to describe the solutions adopted to solve technical difficulties related to priming, vascular access and monitoring and then to evaluate clinical results. Between 1982 and 2000, 51 consecutive children (28 male, 23 female) with a mean age of 4.9 +/- 4.8 years (3 months-14.8 years) and a mean weight of 19.7 +/- 12.8 kg (5-52 kg), with renal and/or extra-renal diseases requiring apheretic procedures were selected for the study. The overall number of procedures performed were: 226 plasma-exchange (PE), 6 LDL-apheresis (LDL-A) and 8 protein A immunoadsorption (IAPA) sessions. Our therapeutic protocol involves hematic flux of 20-100 ml/min and ultrafiltration of 5-20 ml/min. In each 70-95 minute session we exchanged plasmatic volume with fresh frozen plasma or with a solution of 6% albumin in lactated Ringer's, using heparin (10-20 UI/kg/h). We used Paired Filtration Dialysis Monitor in PE and LDL-A; Citem 10 in IAPA. As plasma separator, we used a filter made of polypropylene, 0.2 m2 surface, 30 ml priming (Hemaplex BT 900). Hemolytic uremic syndrome was the most commonly treated disease (18/51 cases) with good results in 10/18 cases. We recorded, good results in vasculitis as well, in one girl with focal glomerulosclerosis in transplanted kidney and rapid improvement in all children with Guillaine-Barré Syndrome. PE treatment was effective in metabolic disorders such as tirosynemia and familiar hypercholesterolemia. Only 4/12 patients with acute liver failure due to viral hepatitis recovered. We had poor results in the remaining eight cases. Complications were rare and no viral infection was found in any patient. Our data show that it is possible to use these procedures in pediatric patients even though clinical indications and real effectiveness still need to be cleared up.