Adaptive evolution of human immunodeficiency virus-type 1 during the natural course of infection

The rate of progression to disease varies considerably among individuals infected with human immunodeficiency virus-type 1 (HIV-1). Analyses of semiannual blood samples obtained from six infected men showed that a rapid rate of CD4 T cell loss was associated with relative evolutionary stasis of the HIV-1 quasispecies virus population. More moderate rates of CD4 T cell loss correlated with genetic evolution within three of four subjects. Consistent with selection by the immune constraints of these subjects, amino acid changes were apparent within the appropriate epitopes of human leukocyte antigen class I-restricted cytotoxic T lymphocytes. Thus, the evolutionary dynamics exhibited by the HIV-1 quasispecies virus populations under natural selection are compatible with adaptive evolution.     

Anti-nutritional constituents of six underutilized legumes grown in Nigeria

Six underutilized legume seeds grown in Nigeria namely, red and white lima beans, brown and cream pigeon pea, African yam bean and jackbean were analysed for different anti-nutritional factors Sojasapogenol B was identified as the predominant sapogenol in lima beans and jackbeans by capillary gas chromatography. The content of total inositol phosphates and individual inositol phosphates (IP6, IP5, IP4 and IP3) were analysed by ion-pair HPLC, being in the range of other legumes. Trace quantities of lupanine were identified as the alkaloid in jackbean. alpha-Galactosides were present in all the legume seeds, stachyose being the predominant galactoside in lima beans, African yam bean and jackbean, and verbascose in pigeon pea. The haemagglutinating activity was estimated as a measure of the lectin content of the samples. African yam bean was found to have the highest heamagglutinating activity. Tannins were found to be in low quantities. The presence of these anti-nutrients in relation to the nutritional value of the legume is discussed.     

Tooth recontouring/reshaping a must in the preparation for removable partial denture

OBJECTIVE: To assess the extent of functional and vocational rehabilitation achieved by elderly inner-city patients sustained on maintenance hemodialysis. DESIGN: Inception cohort study of elderly patients who have end-stage renal disease using a modified Karnofsky rating system. The need for a wheelchair, participation in household activities, and effect of comorbid conditions were noted. Current status was compared with patient's recollection of functional activity level 2 years before commencing maintenance hemodialysis. SETTING: Seven outpatient, hospital-affiliated and private hemodialysis units in Brooklyn, NY. PATIENTS: One hundred four patients aged 65 years or older who were receiving maintenance hemodialysis for at least 6 months. MAIN OUTCOME MEASURES: A score of 76 or greater on a modified Karnofsky scale indicated independent function at a level that permitted participation in activities beyond those mandated by the hemodialysis regimen. A comorbidity score 6 or greater on a newly constructed index correlated with severe debility. Employment status was also recorded. RESULTS: Present functional activity had deteriorated to a modified Karnofsky score of 66 +/- 12.3 (+/- SD) compared with patients' recollection of a mean score of 84 +/- 14.3 (P < .001) 2 years before initiation of hemodialysis. Diabetic patients had a lower score than nondiabetic patients. The mean comorbidity index of the entire study group was 7.8 +/- 2.9 (mean +/- SD). Within the diabetic subset, severe debility constrained 71 patients (68%) to limit all activity to their residence with the exception of travel to and from their dialysis facility. By contrast, 2 years prior to commencing dialytic therapy, 81 diabetic patients (78%) had interests and activities that took them outside their homes (P < .001). Generalized weakness was the most common explanation given for the lack of outside activity by nine patients (9%) who were wheelchair bound. Erythropoietin, though regularly administered to 87 patients (84%) in the study group, was unsuccessful in raising mean hematocrit reading above 0.28 +/- 0.05 (mean +/- SD). CONCLUSIONS: Maintenance hemodialysis does not return inner-city elderly patients to their predialysis level of functioning. Few elderly, diabetic hemodialysis patients conduct any substantive portion of their lives outside their homes. For nondiabetic patients, the modified Karnofsky score of whites (70.4 +/- 11.9) and blacks (66.5 +/- 15.3), though low, was equivalent (P < .4).     

Anastrozole versus megestrol acetate in the treatment of postmenopausal women with advanced breast carcinoma: results of a survival update based on a combined analysis of data from two mature phase III trials. Arimidex Study Group

BACKGROUND: This report presents the results of a survival update based on the combined data from two studies that compared the efficacy and tolerability of anastrozole (1 or 10 mg once daily), a selective, nonsteroidal aromatase inhibitor administered orally, and megestrol acetate (40 mg 4 times daily) in the treatment of postmenopausal women with advanced breast carcinoma whose disease had progressed after treatment with tamoxifen. METHODS: Two randomized, parallel-group, multicenter trials were conducted, involving a total of 764 patients. The two trials were identical in design; both were double blind for anastrozole and open label for megestrol acetate. Overview analyses were conducted with the intent of strengthening the interpretation of results from each trial. The median follow-up duration for this survival update was 31 months. RESULTS: At the clinical dose of 1 mg daily, anastrozole demonstrated a statistically significant survival advantage over megestrol acetate, with a hazard ratio of 0.78 (P < 0.025)(0.60 < 97.5% confidence interval [CI] <1.0). The 1 mg anastrozole group also had a longer median time to death (26.7 months) compared with 22.5 months for the megestrol acetate group. The 10 mg anastrozole group also had a survival benefit over the megestrol acetate group, with a hazard ratio of 0.83 (P=0.09, not significant)(0.64 < 97.5% CI < 1.1). Higher 2-year survival rates were observed for both anastrozole treatment groups than for the megestrol acetate group (56.1%, 54.6%, and 46.3% for the groups given 1 mg anastrozole, 10 mg anastrozole, and megestrol acetate, respectively). CONCLUSIONS: This combined analysis of two trials of postmenopausal patients with advanced breast carcinoma has clearly demonstrated that, after disease progression with tamoxifen, treatment with anastrozole 1 mg once daily results in a statistically and clinically significant advantage over a standard treatment, megestrol acetate. This important benefit, in addition to the good tolerability profile of anastrozole, supports the use of this drug as a valuable new treatment option for this patient population.     

Effects of angiotensin II-receptor blockade with losartan on insulin sensitivity, lipid profile, and endothelin in normotensive offspring of hypertensive parents

BACKGROUND: Acute liver failure (ALF) secondary to malignant infiltration of the liver is rare and is diagnosed often only after death. AIMS: To determine diagnostic factors and particular clinical patterns of illness. METHODS: Review of case notes from all patients with ALF secondary to hepatic infiltration admitted to this unit over an 18 year period (1978-1995). RESULTS: From a total of 4020 admissions, 18 patients were identified with ALF attributable to hepatic infiltration. Mean age was 40.7 years. Aetiology was non-Hodgkin's lymphoma in nine patients, Hodgkin's disease in three, infiltrative metastatic carcinoma in four, and haemophagocytosis with no precipitant cause in two cases. Prodromal symptoms were non-specific, but occurred at least two to four weeks before onset of ALF, making the presence of such symptoms of value in differential diagnosis of the cause of ALF. Clinical examination and investigations were unhelpful in distinguishing these cases from more usual causes of ALF. Usually, the clinical course was of rapid deterioration and death from multiorgan failure, and only one patient survived. Diagnosis was made during life in 15 patients. Histology showed evidence of widespread hepatocellular necrosis, with diffuse infiltration by tumour cells rather than focal cellular aggregation. CONCLUSIONS: Only with accurate histological diagnosis from liver biopsy and institution of specific therapy early in the management of such patients will the best chance of recovery be achieved. In every case of ALF with prodromal symptoms or abnormal imaging, hepatic histology should be obtained by liver biopsy as soon as possible to diagnose infiltrative hepatic disease.     

Cranial cystic epidermoid: report of two cases and review of the literature

Among non-Hodgkin's lymphomas occurring in childhood two major histologic subgroups can be identified: (1) Burkitt's lymphoma and (2) T-cell lymphoblastic lymphoma, an uncommon high-grade malignant non-Hodgkin's lymphoma. Although Burkitt's lymphoma with maxillofacial involvement is a well-documented disease, T-cell lymphoblastic lymphoma in the perioral region is rare. An unusual case of T-cell lymphoblastic lymphoma with initial oral manifestation in an 18-month-old child is presented.     

Appendectomy in the surgical staging of ovarian carcinoma

The CAMP reaction between Listeria monocytogenes and Rhodococcus equi was studied by a diffusion assay. Listeria monocytogenes displayed identical cooperative haemolytic effect with supernatant cultures of R. equi or with commercial cholesterol oxidase (COX). This result, even with enzymes of different sources (commercial COX is obtained from Pseudomonas spp.) suggests that this enzyme secreted by R. equi has a crucial role in the synergistic haemolytic (CAMP) reaction with L. monocytogenes. The mechanism of the cooperative lytic process between L. monocytogenes and R. equi may represent a different and novel mechanism reaction, in which the COX may not act as a conventional second-step factor, and a reaction different to the direct interaction with the cholesterol of the erythrocyte membrane may be involved.     

Bioactive glass and glass-ceramic-coated hip endoprosthesis: experimental study in rabbit

Co–Cr–Mo endoprostheses with a dual bioactive glass (BG) coating and titanium implants coated with a bioactive glass-ceramic (BGC) were studied under lead-bearing conditions in the rabbit hip. The dual BG coating contained an inner layer of high durability and an outer bioactive layer. Each type of coating improved the stabilization of prosthesis during the experiment period of 8 weeks compared to non-coated control implants. EDXA analysis confirmed the ability of BG and BGC coatings to bond chemically to bone. The BGC coating on titanium alloy proved superior to the dual BG coating on Co–Cr–Mo prosthesis with regard to bone formation on the surface of the implant. The bioactive top layer of the dual BG coating showed resorption, especially in the areas without direct bone contact. This is explained by partial crystallization of the glass during firing. Thermal discrepancy between BGC coating and titanium core caused cracking of the coating, which remains a major obstacle to its use as a bioactive coating.     

Bioactive glass induced in vitro apatite formation on composite GBR membranes

The aim of this study was to investigate in vitro bioactivity of different thermoplastic biodegradable barrier membranes. Three experimental GBR membranes were fabricated using Poly(epsilon-caprolactone-co-D: ,L-lactide) P(CL/DL-LA) and particulate bioactive glass S53P4 (BAG; granule size 90-315 microm): (A) composite membrane with 60-wt.% of BAG, (B) membrane coated with BAG; and (C) copolymer membrane without BAG. Membranes were immersed in simulated body fluid (SBF), and their surfaces were characterized with SEM, XRD and EDS after 6 and 12 h and after 1, 3, 5, 7, and 14 days. Calcium phosphate (Ca-P) surface formation was observed on both composite membranes (A and B) but not on the copolymer membrane without bioactive glass (C). The Ca-P precipitation appeared to be initiated on the bioactive glass followed by growth of the layer along the polymer surface. In 6-12 h ion dissolution of the bioactive glass led to formation of the silica rich layer on the surface of the exposed glass granules on composite membrane B whereas only small amounts of silica was observed on the polymer surface of the composite membrane A. At 24 h nucleation of Ca-P precipitation was observed, and by 3-5 days membrane surface was covered with a uniform Ca-P layer transforming from amorphous to low crystalline structure. At 7 days composition and structure of the apatite surface resembled the apatite in bone. Once nucleated, the surface topography seemed to have significant effect on the growth of the apatite layer.