CT features of calcifications in abdominal malignant fibrous histiocytoma

Driven by the need for a readily available, non-immunological tissue that possesses many of the characteristics of normal human skin, tissue-engineered skin has been developed. For over a decade, laboratory grown or processed skin has been under investigation and, in some cases, available as an alternative to autologous grafts. Apligraf, derived from neonatal foreskin and bovine type I collagen, is the first bi-layered living skin equivalent approved in the US and other countries for use in venous ulcers. Apligraf is effective both in the treatment of refractory venous ulcers and for acute wounds such as surgical excision sites and split thickness donor sites. Apligraf is safe and is not clinically rejected. Its ultimate fate is not known, so it may well work to aid healing in a variety of ways including graft 'take' and as a stimulus for healing.     

Cycloalkylpyranones and cycloalkyldihydropyrones as HIV protease inhibitors: exploring the impact of ring size on structure-activity relationships

Previously, 3-substituted cycloalkylpyranones, such as 2d, have proven to be effective inhibitors of HIV protease. In an initial series of 3-(1-phenylpropyl) derivatives with various cycloalkyl ring sizes, the cyclooctyl analog was the most potent. We became interested in exploring the influence of other structural changes, such as substitution on the phenyl ring and saturation of the 5,6-double bond, on the cycloalkyl ring size structure-activity relationship (SAR). Saturation of the 5,6-double bond in the pyrone ring significantly impacts the SAR, altering the optimal ring size from eight to six. Substitution of a sulfonamide at the meta position of the phenyl ring dramatically increases the potency of these inhibitors, but it does not change the optimal ring size in either the cycloalkylpyranone or the cycloalkyldihydropyrone series. This work has led to the identification of compounds with superb binding affinity for the HIV protease (Ki values in the 10-50 pM range). In addition, the cycloalkyldihydropyrones showed excellent antiviral activity in cell culture, with ED50 values as low as 1 microM.     

Post-thaw sperm motility, cAMP concentration and membrane lipid peroxidation after stimulation with pentoxifylline and platelet-activating factor

Earlier studies have demonstrated that pentoxifylline (PTX) and platelet-activating factor (PAF) can significantly improve the motion parameters of post-thaw human spermatozoa. This study has investigated the effects of PAF, PTX and their combination on cyclic adenosine monophosphate (cAMP) concentrations and membrane lipid peroxidation (LPO) in post-thaw human spermatozoa. Washed spermatozoa from normal volunteers (n = 10) were cryopreserved in Test-yolk buffer using a standard protocol. After 2 weeks the sperm samples were thawed, washed and incubated with either 1 microM PAF, 3 mM PTX or 0.5 microM PAF plus 1.5 mM PTX. Video sequences were recorded at 0, 30, 60, and 120 min for analysis of sperm motion parameters using the Cell Track Sperm Analysis System. Concentrations of cAMP were assessed by radioimmunoassay, and LPO levels were measured by malondialdehyde-thiobarbituric acid reactivity. Our studies indicate a time-course stimulatory effect with overall maximal stimulation observed in samples treated with the combination of PAF and PTX. The maximal stimulation of percentage motility compared to control was observed at 60 min in samples treated with PAF, PTX, or PAF plus PTX. PAF plus PTX stimulated straight-line velocity (VSL), curvilinear velocity (VCL) and lateral head displacement (ALH) after 30 min incubation. The primary effect of PAF was observed on VSL, while the main effect of PTX was on VCL. cAMP concentrations were 3-fold higher than controls in samples treated with PTX or PAF plus PTX. cAMP concentrations in PAF-treated samples did not differ significantly from controls. No significant differences were observed between any groups for LPO.(ABSTRACT TRUNCATED AT 250 WORDS)     

Serum HIV-1 RNA levels and time to development of AIDS in the Multicenter Hemophilia Cohort Study

Normal women produce small amounts of active androgens. When androgen levels are elevated, such as for example in the polycystic ovary syndrome, this is followed by the development of male physical characteristics and muscle mass, structure and function as well as android adipose tissue distribution and function. Psychological features and stress reactions also seem similar to those of men. Such women have an increased risk of developing hypertension, non-insulin-dependent diabetes mellitus and cardiovascular disease. Recent data have shown that these physical, and psychological characteristics, as well as risk of ill health, are also found in the population of women selected at random. Women in the lowest quintiles of levels of sex-hormone-binding globulin--an indicator inversely related to active androgens--are at risk of developing hypertension, non-insulin-dependent diabetes mellitus and cardiovascular mortality. The mechanism probably includes muscular insulin resistance, following a relative androgen excess. It is thus apparent that androgens, even within the highest levels of the nonselected population of women, are powerful predictors of serious disease development. The population at risk might be as large as about 20% of middle-aged women. This is an area of female disease risk which requires more attention in screening and intervention procedures.     

Ineffective and non-nodulating mutant strains of Rhizobium japonicum

Mutant strains of Rhizobium japonicum that were unable to allow the Corsoy cultivar of soybean to reduce acetylene or fix N2 were isolated. These strains grow as well as the wild type in a variety of media. Mutant strains SM1 and SM2 did not form nodules on the host plant; however, they reduced acetylene in the nonsymbiotic assay. Strains SM3 and SM4 produced nodules that did not have the characteristic pink pigment caused by leghemoglobin. The nodules formed by these strains also were small. One mutant strain, SM5, produced large pink nodules. The lesion in this strain seems to be in the gene that specifies nitrogenase component II.     

The structure of L-lactate oxidase from Mycobacterium smegmatis

1. An improved purification was developed for L-lactate oxidase from Mycobacterium smegmatis. 2. The mol.wt. of the native enzyme by a sedimentation-equilibrium analysis was 345 000, and other ultracentrifuge methods gave values in the range 345 000-350 000. 3. An amino acid analysis, determinations of protein and flavin, a sedimentation-velocity analysis and an approach to equilibrium analysis gave values for the subunit mol.wt. in the range 43 500-47 000. 4. It was concluded that L-lactate oxidase contains eight subunits of mol.wt. 43 500. 5. Cross-linking of the subunits with dimethyl suberimidate and electron-microscopy studies were consistent with an octameric structure.     

Isolation of Actinomyces viscosus from two patients with clinical infections

The isolation of Actinomyces viscosus from two patients is described. One was a case of multiple myeloma, the organism being found on blood culture; the other was a patient with a submandibular abscess. These are believed to be the first such isolations of A. viscosus in this country.     

Derepressed alloantigen in transplacentally induced lung tumor coded for by H-2 linked gene

A transplacentally induced lung tumor of strain C3Hf mice grows progressively when transplanted to (C3Hf X A)F1 hybrid mice but not when transplanted to C3Hf recipients. Progressive tumor growth occurs in [(C3Hf X A)F1 X C3Hf] backcross mice inheriting the H-2a haplotype from the F1 parent. Furthermore, radioresistant immunity to the lung tumor can be induced in C3Hf mice by immunization with normal tissue of B10.A and B10.A(2R) but not of B10 or B10.A(5R) strain mice.     

Analysis of a large pedigree with elliptocytosis, multiple lipomatosis, and biological false-positive serological test for syphilis

Elliptocytosis, multiple lipomatosis, and biological false-postive serological test for syphilis (BFPSTS) were found in a single individual. One hundred eighty relatives were tested for the three diseases: 74 were typed for seven blood group antigens, and 58 were typed for four electrophoretic enzyme markers. Likelihood analysis of the pedigree data confirmed independent dominant inheritance for elliptocytosis and lipomatosis. BFPSTS appears dominant, but the analysis was inconclusive. No linkages were found between any disease gene and any marker gene. Two female pedigree members with BFPSTS developed systemic lupus erythematosus, a finding in agreement with the previously described association. The analysis did not lead to any conclusions about the causal relationship between the two traits.