Homocysteine Levels in Chronic Gastritis and Other Conditions: Relations to Incident Cardiovascular Disease and Dementia

Background Homocysteine levels in circulation are determined by several factors and hyperhomocysteinemia is reportedly associated with cardiovascular diseases and dementia. The aim of this study is to determine the relation of chronic gastritis and other conditions to homocysteine levels and their relation to incident cardiovascular diseases and dementia. Methods An adult population-based cohort (N = 488) was screened for H. pylori infection, gastro-duodenitis (endoscopic biopsies), disease history, and lifestyle factors. Blood samples were analyzed for pepsinogen I and II (gastric function), vitamin B12, folate, homocysteine, and cystatin C (renal function). The methylenetetrahydrofolate reductase C677T polymorphism reportedly associated with hyperhomocysteinemia was analyzed by pyrosequencing. Incident cardiovascular diseases and dementia were monitored during a median follow-up interval of 10 years. Results At baseline, there was a positive relation of S-homocysteine to male gender, age, S-cystatin C, methylenetetrahydrofolate reductase 677TT genotype and atrophic gastritis. During follow-up, cardiovascular diseases occurred in 101/438 and dementia in 25/488 participants, respectively. Logistic regression analysis (adjusting for gender, age at baseline, follow-up interval, BMI, smoking, alcohol consumption, NSAID use, P-cholesterol, and P-triglycerides) showed an association of S-homocysteine higher than 14.5 μmol/l to cardiovascular diseases (OR 2.05 [95% c.i. 1.14–3.70]), but not to dementia overall. Conclusions Gender, age, vitamin B12, folate, renal function, atrophic gastritis and the methylenetetrahydrofolate 677TT genotype were significant determinants of homocysteine levels, which were positively related to incident cardiovascular diseases

GABAergic Gene Expression in Postmortem Hippocampus from Alcoholics and Cocaine Addicts; Corresponding Findings in Alcohol-Naïve P and NP Rats

BACKGROUND:By performing identical studies in humans and rats, we attempted to distinguish vulnerability factors for addiction from neurobiological effects of chronic drug exposure. We focused on the GABAergic system within the hippocampus, a brain region that is a constituent of the memory/conditioning neuronal circuitry of addiction that is considered to be important in drug reinforcement behaviors in animals and craving and relapse in humans. METHODOLOGY:Using RNA-Seq we quantified mRNA transcripts in postmortem total hippocampus from alcoholics, cocaine addicts and controls and also from alcohol-naïve, alcohol preferring (P) and non-preferring (NP) rats selectively bred for extremes of alcohol-seeking behavior that also show a general addictive tendency. A pathway-targeted analysis of 25 GABAergic genes encoding proteins implicated in GABA synthesis, metabolism, synaptic transmission and re-uptake was undertaken. PRINCIPAL FINDINGS:Directionally consistent and biologically plausible overlapping and specific changes were detected: 14/25 of the human genes and 12/25 of the rat genes showed nominally significant differences in gene expression (global p values: 9×10⁻¹⁴, 7×10⁻¹¹ respectively). Principal FDR-corrected findings were that GABBR1 was down-regulated in alcoholics, cocaine addicts and P rats with congruent findings in NSF, implicated in GABAB signaling efficacy, potentially resulting in increased synaptic GABA. GABRG2, encoding the gamma2 subunit required for postsynaptic clustering of GABAA receptors together with GPHN, encoding the associated scaffolding protein gephryin, were both down-regulated in alcoholics and cocaine addicts but were both up-regulated in P rats. There were also expression changes specific to cocaine addicts (GAD1, GAD2), alcoholics (GABRA2) and P rats (ABAT, GABRG3). CONCLUSIONS/SIGNIFICANCE:Our study confirms the involvement of the GABAergic system in alcoholism but also reveals a hippocampal GABA input in cocaine addiction. Congruent findings in human addicts and P rats provide clues to predisposing factors for alcohol and drug addiction. Finally, the results of this study have therapeutic implications

Phase transitions detection using in situ ellipsometry measurements

Knowledge about the optical properties of materials at high pressure and high temperature is needed for EOS research. The ability to detect phase transitions under a dynamic process is essential. Ellipsometry measures the change in the polarization of a probe beam reflected from a surface. From the change in polarization, the real and imaginary parts of the time dependent complex index of refraction, N(ω) = n+ik, can be extracted. Since the optical properties of materials are related to the electronic and structural properties of materials ellipsometry can be used to detect phase transition. Phase transition detection by ellipsometry was tested with planar impact experiment provided by a gas gun. The optical properties of 1020 steel target under different impact pressure were measured. Changes were measured for shock wave pressures larger than 130 kbar due to the α → ε phase transition

Experimental and theoretical investigation of the dynamic properties of aluminum with helium bubbles

The dynamic behavior of aluminum containing helium bubbles was investigated in shock wave experiments. The targets were obtained by mixing melted pure aluminum with 1800 appm 10B powder. After solidification, the targets were neutron irradiated to obtain helium atoms in the bulk from the reaction 10B+n→7Li+4He. Helium atoms further accumulated into bubbles by diffusion in the aluminum bulk. Shock wave experiments were performed by accelerating aluminum impactor into three types of samples: (1) pure aluminum, (2) Al-10B and (3) Al-10B with different concentrations of helium bubbles and different radii. The bubbles radii and concentration were determined experimentally using Transmission Electron Microscopy (TEM). The number of helium atoms in a bubble was calculated from the Electron Energy Loss Spectrum (EELS). The following results were obtained in the experiments: The maximum free surface velocity of shocked samples made Al-10B and Al-10B with different concentrations of helium bubbles and different radii was similar, implying that the pressure on the Hugoniot was the same. Moreover, it was found that the spall strength of these samples was the same. However, it was measured that the spall strength of pure aluminum samples was by 47% higher than that of Al-10B and Al-10B with bubbles samples. An equation of state (EOS) model was developed for describing aluminum with helium bubbles. The bubbles radii and concentrations were used as input parameters in the model. The calculated Hugoniot curve for aluminum with bubbles was not sensitive to the existence of helium, for mass ratio of 10−5 between helium and aluminum, typical for the experiments. This finding is in agreement with the experimental results