Loss of substance of the lateral region of the face

The cardiovascular effects of a partially purified extract of fish oil, enriched in the n-3 series fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), were studied in stroke-prone spontaneously hypertensive rats (SHR-SP) fed with high- and low-sodium diets during 5 weeks. Addition of salt to the low-salt control diet at a level commonly found in human food items (6% NaCl of the dry weight of the diet) produced a remarkable rise in blood pressure, an increase in left ventricular weight-to-body weight ratio (LVH-index) and an increase in kidney weight-to-body weight ratio (RH-index). Fish oil (20% of the dry weight of the diet) did not significantly influence the blood pressure or LVH-index or RH-index during the low-salt control diet. However, fish oil completely prevented the remarkable rise in blood pressure and clearly antagonized the rise of both LVH- and RH-indices, induced by the high-salt diet. The fish oil supplementation increased the levels of the polyunsaturated fatty acids of the n-3 series and decreased those of the n-6 series in plasma and kidney, irrespective of the salt content of the diet. Fish oil lowered serum thromboxane B2 concentration by approximately 75%. During the high-salt diet, fish oil markedly decreased water intake and urine volume, and increased urinary sodium concentration by about 60%. Our findings show that, in addition to an antihypertensive effect, fish oil also decreases LVH and RH. These effects appear to be due to an improved ability to excrete sodium and could be explained by the observed changes in the fatty acid composition and metabolism.     

Three-week hepatitis B vaccination provides protective immunity

To determine whether a 3-week hepatitis B (HB) vaccination could achieve protective immunity, 89 healthy non-immunized young adults received three doses of 20 micrograms each of HBs antigen (GenHevac B, Pasteur) and were randomly assigned to schedule A (n = 44): two doses at day 0, one dose at day 21; or schedule B (n = 45): one dose at days 0, 10 and 21. Seroprotection rates (anti-HBs > or = 10 mIU ml-1) for groups A and B respectively were: 23 and 40% at day 21; and 77 and 91% at day 82 (not significant). Anti-HBs geometric mean titres were higher in group B than in group A (p < 0.05) at days 21 (6.4 versus 3.8) and 82 (77.6 versus 33.5). One year after primary vaccination, the seroprotection rate remained as high as 90% in the vaccinees of group B; after boosting all vaccinees had protective levels of anti-HBs antibodies. Thus 3-week HB vaccination with GenHevac B allowed early and durable protective immunity.     

NMR spectroscopy of human post mortem cerebrospinal fluid: distinction of Alzheimer''s disease from control using pattern recognition and statistics

Mutations of ras oncogenes in 37 human stomach cancers and 13 adenomas were investigated with regard to the histological phenotypes using polymerase chain reaction (PCR), allele-specific oligonucleotide hybridization and/or direct sequencing of the PCR products. The ras mutation was found only in one case (2.7%), the histology of which was poorly differentiated adenocarcinoma. We found no mutation in stomach adenomas. The mutation consisted of a guanine-to-adenine transition in the first base of codon 13 of c-Ki-ras which replaced wild-type glycine with serine, indicating that a putative glycine-to-aspartic acid change is not necessarily the critical event for c-Ki-ras gene activation in codon 13. These results further confirm the infrequency of ras mutation in stomach tumors and also suggest that ras mutations are not specific to the differentiated type of stomach cancer.     

Modeling of acute spinal cord injury in the rat: neuroprotection and enhanced recovery with methylprednisolone, U-74006F and YM-14673

We used a new injury device that produces consistent spinal cord contusion injuries (T8) in rats to compare the behavioral and histologic effects of methylprednisolone sodium succinate (MPSS) administration, the clinical standard of therapy after acute spinal cord injury (ASCI), with the 21-aminosteroid, U-74006F (U74), and the TRH analogue, YM-14673 (YM), at different trauma doses. Three sequential experiments were conducted: Experiment 1. U74 (3.0/1.5/1.5 mg/kg; 10/5/5 mg/kg; 30/15/15 mg/kg), MPSS (30/15/15 mg/kg), or vehicle were administered intravenously (i.v.) at 5 min, 2 and 6 h after the injury (n = 8/group). U74 (10/5/5 mg/kg) and MPSS animals scored better than controls (Days 8-43) in open field walking (OFW); no other differences were seen between groups. Experiment 2. Dose-response evaluation of MPSS determined more effective doses. Groups (n = 16) receiving 30/30/30/30 mg/kg and 60/60/60/60 mg/kg i.v. at 5 min and 2, 4, and 6 h after the injury had better OFW scores than controls (Days 8-29; Day 29). Both groups performed better than controls (Days 8-29) on inclined plane (IP); 30 mg/kg animals scored higher on Day 29. Percentage tissue spared (%TS) at the lesion center was greater for 60 mg/kg animals (23.4%) than controls (17.3%). Experiment 3. Compounds were administered as in experiment 2 (n = 15/group); MPSS (60/30/30/30 mg/kg) and YM (1/1/1/1 mg/kg and 1 mg/kg/day ip) were most effective. YM and MPSS combination produced no additive effects. YM animals scored better than MPSS and control animals in OFW (Days 8-29) and better than controls on IP (Days 8-29; Day 29) and grid walking (Day 29). MPSS animals scored better than controls on IP (Days 8-29). YM and MPSS groups had greater %TS than controls. This series of experiments demonstrates the utility of this injury model and simple behavioral measures for preclinical assessment of pharmacologic agents. Under these experimental conditions, U74 demonstrated equivalent efficacy to MPSS, and YM demonstrated greater efficacy than MPSS in the treatment of ASCI.     

Relative involvement of protein kinase C and of the estrogen receptor in the cytotoxic action of a population of triphenylethylenes on MCF7 cells as revealed by correspondence factorial (CF) analysis

A multivariate statistical method, correspondence factorial (CF) analysis, was used to examine the correlations among the protein binding and cell proliferation effects of a series of 36 di- and triphenylethylenes (DPEs and TPEs). The analysis was applied to a study which measured their competition for estradiol binding to cytosol estrogen receptor (ER), their influence on protein kinase C (PKC) activity under different conditions of enzyme activation, their ability to promote the growth of a breast cancer cell line and to inhibit growth at high concentrations (cytotoxicity). The CF analysis revealed several levels of correlation. First, it distinguished those molecules within the population that stimulated rather than inhibited PKC activity. Second, it made apparent a strong correlation between cytotoxicity and inhibition of Ca++ and phosphatidylserine-dependent PKC activity, which was most marked when the enzyme had been activated by diacylglycerol indicating that PKC inhibition under physiological conditions might contribute to the overall cytotoxicity of these compounds. Third, a lower level of correlation was established between competition for ER binding and cytotoxicity. Taken together, the results suggest that MCF7 cells might be most sensitive to a cytotoxic effect of TPEs (via PKC and other targets) when they at the same time decrease estrogen-stimulated proliferation via an ER-mediated antiestrogenic effect.     

Clonal analysis of focal nodular hyperplasia of the liver

Ligation of CD95 (APO-1/Fas) cell surface receptors induces death in apoptosis-sensitive cells. Induction of apoptosis in adherent gamma interferon-stimulated HT-29 and COLO 205 colon carcinoma cells by cross-linking CD95 with anti-APO-1 monoclonal antibody resulted in detachment of the cells from hyaluronate starting about 1 h after antibody exposure. Loss of adhesion was paralleled by a substantial reduction of the multifunctional cell surface adhesion molecule CD44. As evidenced by cycloheximide treatment, this effect was not caused by impaired protein synthesis. Depletion of surface CD44 was also not due to membrane blebbing, since cytochalasin B failed to inhibit ascension from hyaluronate. Instead, ELISA and time kinetics showed increasing amounts of soluble CD44 in the supernatant of CD95-triggered cells. SDS-PAGE revealed that soluble CD44 had an apparent molecular mass of about 20 kD less than CD44 immunoprecipitated from intact cells. Thus, CD95-triggering induced shedding of CD44. Shedding is a novel mechanism operative in early steps of CD95-mediated apoptosis. Shedding surface molecules like CD44 might contribute to the active disintegration of dying epithelial cells in vivo.     

Production of hydroxyl radicals in contracting skeletal muscle of cats

Reactive oxygen species increase during exhaustive contraction of skeletal muscle, but characterization of the specific species involved and their rates of production during nonexhaustive muscle contraction have not been investigated. We hypothesized that the production rate of hydroxyl radical (.OH) increases in contracting muscle and that this rate is attenuated by pretreatment with deferoxamine (Def) or dimethylthiourea (DMTU). We measured the rate of production of .OH before, during, and after 5 min of intermittent static contraction of the triceps surae muscles in cats (n = 6) using the formation of p-, m-, and o-tyrosines by hydroxylation of phenylalanine. L-Phenylalanine (30 mg/kg i.v.) was administered to each animal 3 min before contraction. Blood samples were collected from the popliteal vein 1 min before contraction; 1, 3, and 4.5 min during contraction; and 1 min after contraction. During and after contraction, the cumulative production rates of p-, m-, and o-tyrosines were elevated by 42.84 +/- 5.41, 0.25 +/- 0.04, and 0.21 +/- 0.03 nmol.min-1.g-1, respectively, compared with noncontracting triceps surae muscles. Pretreatment with Def (10 mg/kg i.v.; n = 5) or DMTU (10 mg/kg i.v.; n = 4) decreased the cumulative rates of production of p-, m-, and o-tyrosines during and after contraction. Additionally, the rate of tyrosine production increased in proportion to the percentage of maximal tension developed by the triceps surae muscles. These results directly demonstrate that .OH is produced in vivo in the skeletal muscle of cats during intermittent static contraction and that production can occur before the onset of fatigue.     

Potassium uptake and water content in hepatocytes isolated from rat livers preserved in Euro-Collins and UW solutions and after transplantation

Isolated hepatocytes from the rat were used to assess the maintenance of liver cell function in relation to the composition of the preservation medium. After separation by collagenase, they were incubated in Krebs-Ringer-Bicarbonate medium (KRB), Euro-Collins (EC), or University of Wisconsin (UW) solutions. Potassium influx, cell volume, and transaminase release were measured in cells freshly separated from control livers or from livers preserved in vitro up to 12 h in these media or having undergone orthotopic liver transplantation (OLT). While ion exchange levels were retained in all media, cells shrank significantly in UW but were able to restore their volume after 3 h of liver preservation. With regard to in vivo conditions, UW appears to be the best medium to prevent edema and to maintain more stable potassium exchange and enzyme production. These results are of value for liver transplantation in humans.     

Apoptosis in the failing human heart

BACKGROUND: Loss of myocytes is an important mechanism in the development of cardiac failure of either ischemic or nonischemic origin. However, whether programmed cell death (apoptosis) is implicated in the terminal stages of heart failure is not known. We therefore studied the magnitude of myocyte apoptosis in patients with intractable congestive heart failure. METHODS: Myocardial samples were obtained from the hearts of 36 patients who underwent cardiac transplantation and from the hearts of 3 patients who died soon after myocardial infarction. Samples from 11 normal hearts were used as controls. Apoptosis was evaluated histochemically, biochemically, and by a combination of histochemical analysis and confocal microscopy. The expression of two proto-oncogenes that influence apoptosis, BCL2 and BAX, was also determined. RESULTS: Heart failure was characterized morphologically by a 232-fold increase in myocyte apoptosis and biochemically by DNA laddering (an indicator of apoptosis). The histochemical demonstration of DNA-strand breaks in myocyte nuclei was coupled with the documentation of chromatin condensation and fragmentation by confocal microscopy. All these findings reflect apoptosis of myocytes. The percentage of myocytes labeled with BCL2 (which protects cells against apoptosis) was 1.8 times as high in the hearts of patients with cardiac failure as in the normal hearts, whereas labeling with BAX (which promotes apoptosis) remained constant. The near doubling of the expression of BCL2 in the cardiac tissue of patients with heart failure was confirmed by Western blotting. CONCLUSIONS: Programmed death of myocytes occurs in the decompensated human heart in spite of the enhanced expression of BCL2; this phenomenon may contribute to the progression of cardiac dysfunction.