Lymphocyte phenotype and lymphokines following anti-thymocyte globulin therapy in patients with aplastic anaemia

Twenty-two patients with adult onset aplastic anaemia were analysed before and after therapy with anti-thymocyte globulin (ATG). Lymphocyte phenotype, lymphokine levels or production, and haematopoietic progenitor cell number were measured 3 months after therapy; clinical response was determined 1 year post-therapy. By flow cytometry there was a significant reduction in both the proportion and absolute number of peripheral blood lymphocytes expressing activation antigen Tac (IL-2 receptor) and in the proportion of HLA-DR+ lymphocytes. For T cells bearing HLA-DR, there were proportional decreases in both activated helper and suppressor cells. There was no statistically significant difference pre-ATG to post-ATG in the absolute numbers of total, helper and suppressor lymphocytes. In all 10 haematologic responders the number of Tac bearing lymphocytes after ATG therapy was in the normal range, but half of 12 non-responding patients continued to have abnormally elevated numbers of Tac+ T cells. The proportion of Tac+ cells were not related to transfusion history. Gamma-interferon levels in serum by radioimmunoassay were elevated in almost half the aplastic patients; post-ATG, gamma-interferon was detectable in only three patients. Haematologic response to ATG therapy was associated with increased numbers of haematopoietic progenitors post-treatment, but pre-treatment values were not predictive of a response. These results are consistent with a pathogenic role for activated T-cells and their lymphokine products and suggest that the target of ATG therapy may be a Tac+ lymphocyte.     

Macular blood flow velocity in sickle cell disease: relation to red cell density.

AIMS/BACKGROUND--While the retinal lesions of sickle cell retinopathy have been well documented, their pathogenesis remains unclear. The purpose of this study was (1) to compare macular blood flow velocity in patients with sickle cell disease and controls, and (2) to determine in sickle cell patients the relation between macular blood flow velocity and red blood cell density. METHODS--Macular blood flow velocity was measured in 18 patients with stable sickle cell disease and 45 normal controls using blue field entoptoscopy. Red blood cell density was determined by the phthalate ester density method. RESULTS--There were no significant differences between patients and controls for leucocyte velocity. However, in the sickle cell patients leucocyte velocity in the macular capillaries was significantly negatively associated with greater range of red blood cell density (p < 0.002 and p < 0.04 for right and left eyes, respectively). CONCLUSION--These results suggest that in sickle cell patients heterogeneity of the density of the red blood cells may slow down macular capillary blood flow.     

Metabolism of albendazole and albendazole sulphoxide by ruminal and intestinal fluids of sheep and cattle.

1. The metabolism of albendazole (ABZ), albendazole sulphoxide (ABZSO) and albendazole sulphone (ABZSO2) by ruminal, abomasal and ileal fluids of sheep and cattle was investigated under anaerobic conditions in vitro. 2. None of the compounds was metabolically changed by incubation with abomasal fluids of sheep and cattle. 3. ABZ and ABZSO were extensively metabolized by sheep and cattle ruminal and ileal fluids. ABZSO2 was unaffected by incubation with these gastrointestinal fluids. 4. The rate of ABZ oxidation into ABZSO was greater for cattle ruminal and ileal fluids than for sheep fluids. 5. ABZSO was reduced back to ABZ by ruminal and ileal fluids of both species. This reducing activity was significantly higher for both ruminal and ileal fluids of sheep compared with those of cattle.     

The gelatinous bone marrow (serous atrophy) in patients with acquired immunodeficiency syndrome. Evidence of excess sulfated glycosaminoglycan.

Patients with the acquired immunodeficiency syndrome uniformly exhibit hematologic abnormalities characterized by anemia and/or pancytopenia. In a study of 75 consecutive bone marrow biopsy specimens from patients with acquired immunodeficiency syndrome, 29% exhibited serous atrophy, characterized by marrow hypoplasia, fat atrophy, and deposition of extracellular "gelatinous" material (gelatinous transformation). The latter material was composed exclusively of glycosaminoglycans (alcian blue positive at pHs of 2.5 and 1.0, and sensitive to testicular hyaluronidase digestion). Excess glycosaminoglycan, which significantly alters the bone marrow microenvironment, is detrimental to erythropoiesis. The present findings support the concept that the damaged hematopoietic inductive microenvironment in patients with acquired immunodeficiency syndrome leads to failure of hematopoiesis, and, hence, to peripheral hematologic abnormalities.     

Prevalence of different types of lysosomal storage diseases in saudi arabia

Summary The frequency of different types of lysosomal storage diseases in 125 referred cases, collected over three years, was compared to the occurrence elsewhere. The data suggest that mucopolysaccharidosis (MPS) type IVA (Morquio disease), multiple sulphatase deficiency, Niemann-Pick disease type B, GM2 gangliosidosis type 0 (Sandhoff disease), and ceroid lipofuscinosis (Jansky-Bielschowsky and Batten-Spielmeyer-Vogt syndromes) are encountered frequently in Saudi Arabia, as compared to other storage diseases. In contrast, some other diseases such as the adult variant of Gaucher's disease were not observed. Half of the GM2 gangliosidosis type 0 cases originated from one large tribe in the country. Other conditions did not show tribal predilection. The ceroid lipofuscinosis cases in Saudi Arabia originated from four large families. Consanguineous marriages taking place within tribal boundaries probably account for the pattern observed.     

Serum protein s-100 predicts clinical outcome in patients with melanoma treated with adjuvant interferon--comparison with tyrosinase rt-PCR

OBJECTIVE: To study the clinical value of the determination of serum S-100 protein as a single tumor marker or in combination with tyrosinase RT-PCR in patients with melanoma receiving adjuvant interferon. PATIENTS AND METHODS: Patients were tested for serum S-100 protein luminoimmunometric assay and for blood tyrosinase mRNA (RT-PCR), before starting interferon and every 2-3 months thereafter. RESULTS: One hundred and six patients (stage IIA, 27; IIB, 19; III, 49; and IV, 11) were included in the study. Median follow-up was 51 months (range 2-76). In the univariate analysis, under treatment S-100 > or =0.15 microg/l and a positive RT-PCR correlated with a lower disease-free survival and overall survival (OS). In the multivariate analysis, clinical stage, under therapy positive RT-PCR and S-100 levels > or =0.15 mug/ml, were independent prognostic factors for OS. The hazard ratio for OS was 3.9 (95% CI, 1.67-9.15; p = 0.004) and 2.2 (95% CI, 1.05-4.6; p = 0.016) for S-100 > or =0.15 microg/l and positive RT-PCR, respectively. When both techniques where combined, a positive RT-PCR indicated a poorer clinical outcome only in patients with S-100 <0.15 microg/l. CONCLUSIONS: S-100 > or =0.15 microg/l and a positive RT-PCR during adjuvant interferon therapy indicate a high risk of death in resected melanoma patients. S-100 determination has a higher positive predictive value than RT-PCR, while tyrosinase RT-PCR adds prognostic information in patients with S-100 <0.15 microg/l.     

Aeromonas spp. and traveler's diarrhea: clinical features and antimicrobial resistance

Traveler's diarrhea is the most common health problem of international travelers. We determined the prevalence of Aeromonas spp. associated with traveler's diarrhea and analyzed the geographic distribution, clinical features, and antimicrobial susceptibility. Aeromonas spp. were isolated as a cause of traveler's diarrhea in 18 (2%) of 863 patients. A. veronii biotype sobria was isolated in nine patients, A. caviae in seven patients, and A. jandaei and A. hydrophila in one patient each. Aeromonas spp. were isolated with a similar prevalence in Africa, Latin America, and Asia. Watery and persistent diarrhea, fever, and abdominal cramps were common complaints. All strains were resistant to ampicillin; showed variable resistance to chloramphenicol, tetracycline, and cotrimoxazole; and were susceptible to cefotaxime, ciprofloxacin, and nalidixic acid. The persistence of symptoms made antimicrobial treatment necessary.     

The INMA—INfancia y Medio Ambiente—(Environment and Childhood) project: More than 10 years contributing to environmental and neuropsychological research

Background

In 2003 the INMA—INfancia y Medio Ambiente (Environment and Childhood) project, a Spanish national network of birth cohorts including more than 3500 participants, was set up with the aim to assess the health impacts of pre- and postnatal environmental exposures on children. The project has published more than 60 papers on maternal and environmental factors related to neuropsychological development in children, one of the main research interests within the project. With the present review, we evaluate the evidence provided by the INMA project on this topic and discuss how the data can contribute to cover the challenges that children’s environmental health research will face in the coming years.

Low concentrations of ketamine initiate dendritic atrophy of differentiated GABAergic neurons in culture

Administration of subanesthetic concentrations of ketamine, a noncompetitive antagonist of the N-methyl-d-aspartate (NMDA) type of glutamate receptors, is a widely accepted therapeutic modality in perioperative and chronic pain management. Although extensive clinical use has demonstrated its safety, recent human histopathological observations as well as laboratory data suggest that ketamine can exert adverse effects on central nervous system neurons. To further investigate this issue, the present study was designed to evaluate the effects of ketamine on the survival and dendritic arbor architecture of differentiated gamma-aminobutyric acidergic (GABAergic) interneurons in vitro. We show that short-term exposure of cultures to ketamine at concentrations of > or =20 microg/ml leads to a significant cell loss of differentiated cells and that non-cell death-inducing concentrations of ketamine (10 microg/ml) can still initiate long-term alterations of dendritic arbor in differentiated neurons, including dendritic retraction and branching point elimination. Most importantly, we also demonstrate that chronic (>24 h) administration of ketamine at concentrations as low as 0.01 microg/ml can interfere with the maintenance of dendritic arbor architecture. These results raise the possibility that chronic exposure to low, subanesthetic concentrations of ketamine, while not affecting cell survival, could still impair neuronal morphology and thus might lead to dysfunctions of neural networks.