Role for interleukin-1 (IL-1) in benzene-induced hematotoxicity: inhibition of conversion of pre-IL-1 alpha to mature cytokine in murine macrophages by hydroquinone and prevention of benzene-induced hematotoxicity in mice by IL-1 alpha

Chronic exposure of humans to benzene (BZ), a myelotoxin, causes aplastic anemia and acute leukemia. The stromal macrophage that produces interleukin-1 (IL-1), a cytokine essential for hematopoiesis, is a target of BZ's toxicity. Monocyte dysfunction and decreased IL-1 production have been shown to be involved in aplastic anemia in humans. Hydroquinone (HQ), a toxic bone marrow (BM) metabolite of BZ, causes time- and concentration-dependent inhibition of processing of the 34-Kd pre-interleukin-1 alpha (IL-1 alpha) to the 17-Kd mature cytokine in murine P388D1 macrophages and BM stromal macrophages, as measured by Western immunoblots of cell lysate proteins using a polyclonal rabbit antimurine IL-1 alpha antibody. HQ over a 10-fold concentration range had no effect on the lipopolysaccharide (LPS)-induced production of pre- IL-1 alpha precursor or on cell viability or DNA and protein synthesis. Stromal macrophages obtained from the femoral BM of C57Bl/6 mice exposed to BZ (600 or 800 mg/kg body weight) for 2 days were incapable of processing the 34-Kd pre-IL-1 alpha to the mature 17-Kd cytokine when stimulated in culture with LPS. Stromal macrophages from mice coadministered BZ and indomethacin, a prostaglandin H synthase (PHS) inhibitor that has been shown to prevent BZ-induced myelotoxic and genotoxic effects in mice when coadministered with benzene were able to convert the pre-IL-1 alpha to mature cytokine. Administration of recombinant murine IL-1 alpha (rMuIL-1 alpha) to mice before a dose of BZ that causes severe depression of BM cellularity completely prevents BM depression, most probably by bypassing the inability of the stromal macrophage in BZ-treated animals to process pre-IL-1 alpha to the mature cytokine.     

<Emphasis Type="Italic">TCF7L2</Emphasis>variant genotypes and type 2 diabetes risk in Brazil: significant association,but not a significant tool for risk stratification in the general population

Background  

Genetic polymorphisms of the TCF7L2 gene are strongly associated with large increments in type 2 diabetes risk in different populations worldwide. In this study, we aimed to confirm the effect of the TCF7L2 polymorphism rs7903146 on diabetes risk in a Brazilian population and to assess the use of this genetic marker in improving diabetes risk prediction in the general population.     

Direct evidence for the involvement of carbohydrate sequences in human sperm-zona pellucida binding

Several lines of evidence indicate that mammalian fertilization is initiated via a binding process that is dependent upon the recognition of oligosaccharide sequences associated with zona pellucida (ZP) glycoproteins. Here, specific chemical and enzymatic methods were employed to modify human ZP and to test their effects on sperm binding in the hemizona assay system (HZA). Periodate oxidation of human ZP under very mild conditions (10 min, 0 degrees C, 1 mM sodium m- periodate) that attacks only terminal sialic acid resulted in a 30% loss of human sperm binding in the HZA [hemizona index (HZI) = 70.2 +/- 10.9, n = 22; P < 0.05]. Periodate oxidation under mild conditions (1 h, 23 degrees C, 10 mM sodium m-periodate) caused a 40% decrease in binding (HZI = 60.8 +/- 10.3; n = 24; P< 0.01). Treatment of human ZP with neuraminidase caused a substantial increase in sperm binding to human ZP (HZI = 297 +/- 45, n = 22; P < 0.01). These findings indicate that there are sialic acid dependent binding sites coexisting with binding sites that are obscured by sialic acid. To determine the periodate sensitivity of these obscured sites, hemizona were first digested with neuraminidase and subsequently subjected to mild periodate oxidation. The combined enzymatic and chemical treatments caused a 79% decrease in sperm binding compared to control hemizona (HZI = 20.7 +/- 4.4, n = 16; P < 0.001). Human sperm-ZP interaction was also increased by digestion of human ZP with endo-beta-galactosidase (HZI = 710 +/- 232, n = 14; P < 0.01), indicating that potential binding sites for spermatozoa are also obscured by lactosaminoglycan sequences. These studies support a definitive role for the involvement of ZP-associated glycans in the binding of human spermatozoa to oocytes.      

N-terminal anthranoyl-phenylalanine derivatives as CCK1 receptor antagonists: the final approach

Starting from our lead compound, VL-0395, an anthranilic acid based CCK1 receptor antagonist, and following the well established "step by step" lead investigation strategy, we describe the final step of the anthranilic acid N-terminal optimization. Improvements for both affinity and selectivity towards CCK1 receptors have been accomplished through introduction of the fluoro substituent at C-5 and C-7 position of the indole ring together with the appropriate configuration of the aminoacidic chiral center.     

Characterization of antisecretory and antiulcer activity of CR 2945, a new potent and selective gastrin/CCK(B) receptor antagonist

The antigastrinic, antisecretory and antiulcer activities of CR 2945, (R)-1-naphthalenepropanoic acid,beta-[2-[[2-(8-azaspiro[4.5]dec-8-yl-carbonyl)-4,6-dimethylph enyl] amino]-2-oxoethyl], were investigated in vitro and in vivo in rats and cats. Its activities were compared with those of two gastrin/CCK(B) receptor antagonists, L-365,260 (3R(+)-N-(2,3-dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin -3-yl)-N'-(3-methylphenyl)urea and CAM-1028 (4-[[2-[[3-(1H-indol-3-yl)-2-methyl-1-oxo-2-[[[1,7,7-trimethylbicyclo [2.2.1]hept-2-yl)oxy]carbonyl]amino]propyl]amino]-1-phenylethyl]amino -4-oxo-[1S-1alpha,2beta[S'(S')4alpha]]-butanoate -N-methyl-D-glucamine), of the histamine H2 receptor antagonist, ranitidine, and the proton pump inhibitor, omeprazole. Cytosolic Ca2+ elevation in rabbit parietal cells induced by gastrin (50 nM) was blocked by CR 2945 with an IC50 value of 5.9 nM. CAM-1028 and L-365,260 showed similar activity. CR 2945 antagonized pentagastrin-stimulated gastric acid secretion in rats (ED50 = 1.3 mg kg(-1) i.v. and 2.7 mg kg(-1) i.d.) and cats (1.6 mg kg(-1) i.v.). CR 2945 was slightly less potent than the reference compounds after i.v. administration, whereas after intraduodenal (i.d.) administration, it was more potent than both ranitidine and omeprazole. In the rat, the gastrin antagonism exhibited by CR 2945 was reversible and competitive, with a pA2 value of 7.33. CR 2945 had specific antigastrin activity, as it was unable to antagonize the gastric acid secretion stimulated by histamine or carbachol in rats up to the dose of 30 mg kg(-1). CR 2945 was about as efficacious as ranitidine against the indomethacin- and ethanol-induced gastric ulcers and the cysteamine-induced duodenal ulcer in rats. On the contrary, L-365,260 was only slightly effective. These results suggest that CR 2945 might be a promising compound for the therapy of acid-related disorders, and that its clinical use could help clarify the therapeutic potential of gastrin/CCK(B) receptor antagonists in the gut.     

Colonic motility diagnosis based on colonic pressure

Manometry of the alimentary tract is a valuable and widely used means to evaluate and diagnose the function of the alimentary tract. However, the measurement can be inconvenient due to the invasive method used, and the many factors affecting results. Research on colonic pressure data is even more insufficient. This paper deals with colonic pressure data via an improved method ensuring that pressure data of the whole colon is available. The data is analysed based on the learning vector quantization (LVQ) method. Testing results show that this method distinguishes the normal data and the abnormal data, consistently with the original diagnoses. This method can serve as an assistant diagnosis of colonic motility and contributes to further research on colonic motility based on pressure data.     

Immunologic status of hemophilia patients treated with cryoprecipitate or lyophilized concentrate

We evaluated 37 patients with moderate or severe hemophilia A and six patients with severe factor IX deficiency for clinical or laboratory evidence of immune abnormalities. Patients were assigned to one of four groups according to the type of clotting factor replacement. Twenty patients had received only cryoprecipitate during the two years preceding the evaluation (group I); 11 additional patients were treated predominantly with cryoprecipitate but had also received up to nine bottles of factor VIII concentrate (group II); six patients received factor VIII concentrate (group III); six patients received factor IX concentrate (group IV). There was no clinical or laboratory evidence of immunodeficiency among the 43 patients. The mean absolute number of Th cells was normal in all patient groups, but the mean absolute number of Ts cells was increased compared with controls, both in patients treated with cryoprecipitate and in patients treated with factor VIII or factor IX concentrate. There was no correlation between the Th/Ts ratio and patient age, alanine aminotransferase level, hepatitis serology, in vitro lymphocyte function, or amount of clotting factor administered. Our observations demonstrate that the volunteer or commercial origin of clotting factor replacement cannot fully explain the alterations in lymphocyte subset distribution previously described in patients with hemophilia A.     

Development and course of heart failure after a myocardial infarction in younger and older people

Background Acute myocardial infarction （AMI） is a common cause of heart failure （HF）, which can develop soon after AMI and may persist or resolve or develop late. HF after an MI is a major source of mortality. The cumulative incidence, prevalence and resolution of HF after MI in different age groups are poorly described. This study describes the natural history of HF after AMI according to age. Methods Patients with AMI during 1998 were identified from hospital records. HF was defined as treatment of symptoms and signs of HF with loop diuretics and was considered to have resolved if loop diuretic therapy could be stopped without recurrence of symptoms. Patients were cate- gorised into those aged 〈 65 years, 65-75 years, and 〉 75 years. Results Of 896 patients, 311,297 and 288 were aged 〈 65, 65-75 and 〉75 years and of whom 24%, 57% and 82% had died respectively by December 2005. Of these deaths, 24 （8%）, 68 （23%） and 107 （37%） oc- curred during the index admission, many associated with acute HF. A further 37 （12%）, 63 （21%） and 82 （29%） developed HF that persisted until discharge, of whom 15, 44 and 62 subsequently died. After discharge, 53 （24%）, 55 （40%） and 37 （47%） patients developed I-IF for the first time, of whom 26%, 62% and 76% subsequently died. Death was preceded by the development of HF in 35 （70%）, 93 （91%） and 107 （85%） in aged 〈 65 years, 65-75 years and 〉75 years, respectively. Conclusions The risk of developing HF and of dying after an MI in- creases progressively with age. Regardless of age, most deaths after a MI are preceded by the development of HF.