Effect of mycophenolic acid on TNF alpha-induced expression of cell adhesion molecules in human venous endothelial cells in vitro

1. The characteristic features of the endothelium-mediated regulation of the electrical and mechanical activity of the smooth muscle cells of cerebral arteries were studied by measuring membrane potential and isometric force in endothelium-intact and -denuded strips taken from the rabbit middle cerebral artery (MCA). 2. In endothelium-intact strips, histamine (His, 3-10 microM) and high K+ (20-80 mM) concentration-dependently produced a transient contraction followed by a sustained contraction. Noradrenaline (10 microM), 5-hydroxytryptamine (10 microM) and 9,11-epithio-11, 12-methano-thromboxane A2 (10 nM) each produced only a small contraction (less than 5% of the maximum K+-induced contraction). 3. N(G)-nitro-L-arginine (L-NOARG, 100 microM), but not indomethacin (10 microM), greatly enhanced the phasic and the tonic contractions induced by His (1-10 microM) in endothelium-intact, but not in endothelium-denuded strips, suggesting that spontaneous or basal release of nitric oxide (NO) from endothelial cells potently attenuates the His-induced contractions. Acetylcholine (ACh, 0.3-3 microM) caused concentration-dependent relaxation (maximum relaxation by 89.7 +/- 7.5%, n=4, P<0.05) when applied to endothelium-intact strips precontracted with His. L-NOARG had little effect on this ACh-induced relaxation (n=4; P<0.05). Apamin (0.1 microM), but not glibenclamide (3 microM), abolished the relaxation induced by ACh (0.3-3 microM) in L-NOARG-treated strips (n=4, P<0.05). 4. In endothelium-intact tissues, His (3 microM) depolarized the smooth muscle membrane potential (by 4.4 +/- 1.8 mV, n = 12, P < 0.05) whereas ACh (3 microM) caused membrane hyperpolarization (-20.9 +/- 3.0 mV, n = 25, P< 0.05). The ACh-induced membrane hypepolarization persisted after application of L-NOARG (-23.5 +/- 5.9 mV, n=8, P<0.05) or glibenclamide (-20.6 +/- 5.4 mV, n=5, P<0.05) but was greatly diminished by apamin (reduced to - 5.8 +/- 3.2 mV, n = 3, P< 0.05). 5. Sodium nitroprusside (0.1-10 microM) did not hyperpolarize the smooth muscle cell membrane potential (0.2 +/- 0.3 mV, n=4, P>0.05) but it greatly attenuated the His-induced contraction in endothelium-denuded strips (n-4, P<0.05). 6. These results suggest that, under the present experimental conditions: (i) spontaneous or basal release of NO from endothelial cells exerts a significant negative effect on agonist-induced contractions in rabbit MCA, and (ii) ACh primarily activates the release of endothelium-derived hyperpolarizing factor (EDHF) in rabbit MCA.     

Ultrastructural criteria that prove the similarities between amphibian and human tumors

The relationship between selected foods and nutrients and breast cancer risk was investigated in strata of age and menopausal status using data from a case-control study on breast cancer conducted between June 1991 and April 1994 in six Italian areas. Cases were 2,569 women with histologically confirmed incident breast cancer admitted to the major teaching and general hospitals of the study areas; controls were 2,588 women with no history of cancer admitted to hospitals in the same catchment area as cases for acute, nonneoplastic, nongynecological conditions unrelated to hormonal or digestive tract diseases or to long-term modifications of diet. Dietary habits were investigated using a validated food frequency questionnaire, including 78 foods or food groups. Among food groups, bread was directly and significantly related to breast cancer risk in older women and, consequently, in postmenopause, whereas the protection conferred by fish consumption was stronger in postmenopause and that exerted by raw vegetables was stronger in premenopause. Among nutrients, unsaturated fatty acids were inversely related to breast cancer risk, the association being stronger in postmenopausal and elderly women. The pattern was similar for total fats. For starch, available carbohydrates, and total proteins, no heterogeneity emerged across strata of age and menopausal status. Among micronutrients, protection diminished with increasing age for beta-carotene and calcium, whereas no heterogeneity emerged for vitamin E. Thus this age-specific analysis of the largest investigation to date on diet and breast cancer did not show any consistent pattern of breast cancer risk in relation to selected dietary factors across strata of age and menopausal status.     

The efficacy of recombinant vaccines against hepatitis B and the results of their use in a schedule for pediatric prophylactic inoculations

The results of field clinical trials of Russian and American yeast vaccines against hepatitis B are presented. The study revealed that both vaccines were faintly reactogenic, safe and exhibited high immunological activity. After the full course of immunization following the schedule 0-1-2 months 92.5% and 97.5% of patients receiving, respectively. Russian vaccine "Combiotech" and American vaccine "H-B-Vax II" were found to have specific antibodies. The maximum effect was registered when the vaccines were introduced according to the schedule 0-1-6 months. Seroconversions were observed in 97.5% and 100% of the vaccinees receiving the Russian and American vaccines respectively, in the latter case the highest antibody level being observed. The use of the vaccines within the prophylactic immunization schedule showed that antibodies to hepatitis B appeared in immunized children in 93-100% of cases. Seroconversion indices and the levels of antibodies to diphtheria, tetanus, poliomyelitis and measles were statistically significant and were the same in children receiving only the vaccines according to the immunization schedule and in children immunized, in addition to these vaccines, against hepatitis B.     

Long-term outcome of a prospective randomized trial of conversion from cyclosporine to azathioprine treatment one year after renal transplantation

BACKGROUND: Since the introduction of cyclosporine (CsA), 1-year renal allograft survival has improved, but concern persists about the long-term adverse effects of CsA, especially with respect to renal function and blood pressure. This randomized controlled trial was set up to establish whether withdrawal of CsA would alter long-term outcome. METHODS: Adult patients who, at 1 year after renal transplantation, had a stable serum creatinine of less than 300 micromol/L and who had not had acute rejection within the last 6 months were eligible for entry. Patients were randomized either to continue on CsA (n=114) or to stop CsA and start azathioprine (Aza, n=102). All patients remained on prednisolone. Median follow-up was 93 months after transplantation (range: 52-133 months). RESULTS: There was no significant difference in actuarial 10-year patient or graft survival (Kaplan-Meier), despite an increased incidence of acute rejection within the first few months after conversion. Median serum creatinine was lower in the Aza group (Aza: 119 micromol/L; CsA. 153 micromol/L at 5 years after randomization, P=0.0002). The requirement for antihypertensive treatment was also reduced after conversion to Aza; 75% of patients required antihypertensive treatment at the start of the study, decreasing to 55% from 1 year after randomization in the Aza group and increasing to >80% in the CsA group (55% (Aza) and 84% (CsA) at 5 years after randomization, P<0.005). CONCLUSIONS: Conversion from CsA to Aza at 1 year after renal transplantation results in improvement in both blood pressure control and renal allograft function, and is not associated with significant adverse effects on long-term patient or graft survival.     

Solitary pulmonary papillomas in adults: a clinicopathologic and in situ hybridization study of 14 cases combined with 27 cases in the literature

Solitary endobronchial papillomas in adults are rare neoplasms. Only sporadic cases have been documented. The histologic classification of these tumors remains problematic, and little is known about their clinical behavior. The clinical and pathologic features of 13 endobronchial papillomas and a single endobronchiolar papilloma were reviewed. In situ hybridization for human papillomavirus (HPV) types 6/11, 16/18, and 31/33/51 was performed on seven cases. Twenty-seven additional well-documented cases were identified in a literature review. Human papillomavirus studies were performed in four of the previously reported cases. The 41 neoplasms combined from the Armed Forces Institute of Pathology and literature review were divided into three groups according to their histologic features. Thirty-one of 41 (76%) patients were men. The ages of the patients ranged from 26 to 74 years (median, 57 years). Three morphologically distinct histologic types were recognized; 27 squamous cell papillomas, 7 glandular papillomas, and 7 mixed squamous and glandular papillomas. Squamous papillomas: 23 of 27 (85%) patients were men, and the median age was 54 years. Six of eleven (55%) of these patients smoked. Twenty-six lesions were exophytic and a single lesion had an inverted pattern. Seven of 24 (29%) lesions featured cytologic atypia and 5 of 24 (14%) had viral cytopathic effect. Five of seven (71%) cases examined for HPV DNA were positive. Three of 18 (17%) recurred. Glandular papillomas: Four of seven (57%) patients were women. The mean age was 67 years. One of five (20%) patients smoked. Five lesions were central, and two were peripheral. Four lesions had columnar epithelium, and three had ciliated epithelium. One of six (17%) lesions recurred. Mixed papillomas: five of seven (71%) patients were men. The median age was 64 years. Three of five (60%) patients smoked. Three of seven (43%) lesions featured cytologic atypia. Four of five lesions were examined for HPV DNA and all were negative. No lesions recurred. This study demonstrates that solitary endobronchial papillomas can be separated into three distinct morphologic categories. Squamous cell and mixed papillomas are predominantly lesions of male smokers in their 6th decade. Although cytologic atypia is observed in many cases, the rarity of these tumors and difficulty in separating papillomas from endobronchial papillary squamous carcinomas make generalizations regarding the risk of progression to carcinoma tenuous at best. Human papillomavirus appears to play a pathogenetic role in some squamous cell papillomas, but not in mixed papillomas, yet its presence in the squamous lesions does not correlate with recurrence or malignancy. The first report of an inverted squamous cell papilloma indicates clinical features similar to the more common exophytic squamous cell papillomas. Glandular papillomas, the rarest of all endobronchial papillomas, are found in an older age group than squamous and mixed papillomas, and most-patients are nonsmokers. Based on these findings, all endobronchial papillomas should be completely excised.     

Statistical modeling using preoperative prognostic variables in predicting extracapsular extension and progression after radical prostatectomy for prostate cancer

OBJECTIVE: To predict the risk of extracapsular extension and postoperative recurrence before radical prostatectomy (RP) for prostate cancer. METHODS: We performed multivariate Cox regression analysis on preoperative variables in 260 clinically localized prostate cancer patients who underwent RP. With these data, we constructed a relative risk of recurrence (Rr) equation and an equation to predict the probability of extracapsular extension (PECE) before RP. RESULTS: Rr is calculated as exp[(0.47 x race + 0.14 x PSAST) + (0.13 x worst biopsy Gleason sum) + (1.03 x stage T1c) + (1.55 x stage T2b,c)], where PSAST indicates a sigmoidal transformation of prostate-specific antigen. PECE is calculated as 1/[1 + exp(-Z)], where Z = -2.47 + 0.15 (PSAST) + 0.31 (worst biopsy Gleason sum) + 0.18 (race) + 0.16 (stage T1c) + 0.38 (stage T2b,c). CONCLUSION: These two equations can be used preoperatively to predict the probability of extracapsular disease and the risk of prostate-specific antigen recurrence in patients undergoing RP.     

Expression of genes encoding the E2 and E3 components of the Bacillus stearothermophilus pyruvate dehydrogenase complex and the stoichiometry of subunit interaction in assembly in vitro

Genes encoding the dihydrolipoyl acetyltransferase (E2) and dihydrolipoyl dehydrogenase (E3) components of the pyruvate dehydrogenase (PDH) multienzyme complex from Bacillus stearothermophilus were overexpressed in Escherichia coli. The E2 component was purified as a large soluble aggregate (molecular mass > 1 x 10(6) Da) with the characteristic 532 symmetry of an icosahedral (60-mer) structure, and the E3 as a homodimer with a molecular mass of 110 kDa. The recombinant E2 component in vitro was capable of binding either 60 E3(alpha2) dimers or 60 heterotetramers (alpha2beta2) of the pyruvate decarboxylase (E1) component (also the product of B. stearothermophilus genes overexpressed in E. coli). Assembling the E2 polypeptide chain into the icosahedral E2 core did not impose any restriction on the binding of E1 or E3 to the peripheral subunit-binding domain in each E2 chain. This has important consequences for the stoichiometry of the assembled complex in vivo. The lipoyl domain of the recombinant E2 protein was found to be unlipoylated, but it could be correctly post-translationally modified in vitro using a recombinant lipoate protein ligase from E. coli. The lipoylated E2 component was able to bind recombinant E1 and E3 components in vitro to generate a PDH complex with a catalytic activity comparable with that of the wild-type enzyme. Reversible unfolding of the recombinant E2 and E3 components in 6 M guanidine hydrochloride was possible in the absence of chaperonins, with recoveries of enzymic activities of 95% and 85%, respectively. However, only 26% of the E1 enzyme activity was recovered under the same conditions as a result of irreversible denaturation of both E1alpha and E1beta. This represents the first complete post-translational modification and assembly of a fully active PDH complex from recombinant proteins in vitro.     

The changes of lipids, lipoproteins and apolipoproteins in plasma in ischemic stroke

Contents of lipids (cholesterol CS, triglycerides) as well as levels of CS of lipoproteins of different density and of apolipoproteins A1 and B were measured in blood serum of 31 patients in different periods after of ischemic stroke. The majority of the indices studied were significantly decreased in men in acute periods of the stroke, especially in 8-21 days after the stroke development. Meanwhile, the levels of lipids, CS lipoproteins of both low and very low densities were increased later. Contents of CS of antiatherogenic lipoproteins of high density (HDLP) was low in different periods after the development of disorders of cerebral circulation. This confirms the concept that low level of HDLP is one of the risk factors of ischemic stroke. Decrease of the levels of both lipids and CS of lipoproteins of different density was more pronounced in patients with more severe atherosclerotic damages of the main cerebral arteries. Disorders of metabolism of lipoproteins in ischemic disorders of cerebral circulation are discussed with reference to literary data taking into consideration their heterogeneity. Genetically determined pathology of certain apolipoproteins plays a key role factor in the development of early atherosclerosis and in the elucidation of biochemical markers of the primary damages of cerebral vessels.