Hypothalmic influences on the electrical activity of the olfactory pathway

The cycle of events which leads to an impairment of the immune response in the malnourished child includes poverty, food deprivation and frequent infections. It is of great significance, however, that the marked suppression of the immune response can be repaired reasonably promptly, if the disease commences after the child has attained 1 year of age. Prenatal infection not only generates growth retardation but also a higher maternal to foetal IgG ratio, higher IgM in the neonate and a sustained immune depression. Passive cutaneous anaphylaxis measurements in the baboon skin and specific IgE determinations reveal that the elevated IgE in PEM is due to parasitic infestation and common allergens and has little or no relationship with decreased T-cell function.     

A new mutation in the yeast aspartate kinase induces threonine accumulation in a temperature-regulated way

In Saccharomyces cerevisiae, aspartate kinase (the HOM3 product) regulates the metabolic flux through the threonine biosynthetic pathway through feedback inhibition by the end product. In order to obtain a strain able to produce threonine in a controlled way, we have isolated a mutant allele (HOM3-ts31d) that gives rise to a deregulated aspartate kinase. This allele has been isolated as an extragenic suppressor of ilv1, which confers an Ilv+ phenotype at 37 degrees C but not at 22 degrees C. We have stated that at high temperature the mutant aspartate kinase is slightly more deregulated and shows a higher specific activity, inducing threonine accumulation. The HOM3-ts31d allele carries a mutation that leads to a Ser399 --> Phe substitution in the postulated regulatory region of the enzyme. We have detected other changes in the nucleotide sequence but they are also present in the parental strain, reflecting the genetic differences between different wild-type strains. A sequence comparison among all the reported mutant aspartate kinases suggests that not all residues involved in regulation of the activity are clustered in the so-called regulatory domain, as is the case of that mutated in AK-R7, another deregulated aspartate kinase obtained with the same strategy of ilv1 suppression.     

Impurity temperature correction factors for the transmission grating spectrometer in the TJ-II stellarator

Impurity ion temperature and velocity profiles are obtained across plasmas in the TJ-II stellarator by performing charge-exchange recombination spectroscopy with a diagnostic neutral beam injector. For this, a tridirectional (toroidal plus two poloidal opposing views) multichannel spectroscopic diagnostic, incorporating 12-way fiber arrays, a compact f/1.8 spectrograph, and a back-illuminated CCD, permits Doppler line shifts and widths (of the C VI line at 529.05 nm) to be determined with 1-2 cm spatial resolution. For good photon counting statistics under Li-coated wall conditions, 600?μm diameter fibers collect and transmit light to curved 100?μm wide input slits. When calibrated with a neon pencil lamp this entrance slit width results in a non-Gaussian instrumental function that, if not handled correctly, can result in systematically underestimated impurity temperatures. Here we develop and present correction factors for this effect for a range of conditions.     

Preparation and characterization of comb type polymer coated poly(HEMA/EGDMA) microspheres containing surface-anchored sulfonic acid: Application in γ-globulin separation

Poly(2-hydroxyethyl methacrylate/ethylenglycol dimethacrylate), poly(HEMA/EGDMA) microspheres was prepared via suspension polymerization. After activation of the hydroxyl groups of poly(HEMA/EGDMA) by bromination, surface-initiated atom transfer radical polymerization (ATRP) of glycidylmethacrylate was conducted in dioxane/bipyridine mixture with CuBr as catalyst at 65 °C. The epoxy groups of the poly(glycidylmethacrylate) comb polymer were converted into sulfonic acid groups (as proton-exchange groups) with reaction of sodium sulfite. Synthesized microspheres were characterized by swelling studies, FT-IR spectroscopy, scanning electron microscopy (SEM) and elemental analysis. The microspheres were used as ion-exchange support for adsorption and purification of human γ-globulin (IgG). The maximum γ-globulin adsorption on the ion-exchange adsorbents was observed at between pH 5.0 and 6.0. The IgG adsorption onto the poly(HEMA/EGDMA) microspheres was negligible. The maximum amount of adsorbed γ-globulin was found to be 230.1 mg/g microspheres. The ion-exchange adsorbents allowed one-step separation of IgG from human plasma. The γ-globulin molecules could be repeatedly adsorbed and desorbed with this ion-exchange support without noticeable loss in their IgG adsorption capacity.     

Cholesterol‐Lowering Properties of Whole Cowpea Seed and Its Protein Isolate in Hamsters

ABSTRACT: Hypercholesterolemic hamsters were fed for 4 wk on diets rich in saturated fatty acids and cholesterol, differing only in protein source (20 %): casein (control group, HC), whole cowpea seed (HWS), and cowpea protein isolate (HPI). Hamsters fed on HWS and HPI presented significant reductions in plasma total cholesterol and non‐HDL cholesterol. HPI and HC presented similar protein digestibility, which were significantly higher than that of HWS. Animals fed on HWS presented significantly higher levels of bile acids and cholesterol in feces than did the animals fed on casein or HPI diets. Histological analyses of the liver showed that HC diet resulted in steatosis widely distributed throughout the hepatic lobule, while HWS and HPI diets promoted reductions in liver steatosis. The effectiveness of HWS for modulating lipid metabolism was greater than that of HPI, as measured by plasma cholesterol reduction and liver steatosis.     

Preliminary characterization of an experimental breast cancer cells brain metastasis mouse model by MRI/MRS

PURPOSE: Chemotherapy increases survival in breast cancer patients. Consequently, cerebral metastases have recently become a significant clinical problem, with an incidence of 30-40% among breast carcinoma patients. As this phenomenon cannot be studied longitudinally in humans, models which mimic brain metastasis are needed to investigate its pathogenesis. Such models may later be used in experimental therapeutic approaches. MATERIAL AND METHODS/RESULTS: We report a model in which 69% of the animals (9/13 BALB/c nude mice) developed MR-detectable abnormal masses in the brain parenchyma within a 20 to 62-day time window post intra-carotid injection of 435-Br1 human cells. The masses detected in vivo were either single (7 animals) or multiple (2 animals). Longitudinal MR (MRI/MRS) studies and post-mortem histological data were correlated, revealing a total incidence of experimental brain metastases of 85% in the cases studied (11/13 animals). ADC maps perfectly differentiated edema and/or CSF areas from metastasis. Preliminary MRS data also revealed additional features: decrease in N-acetyl aspartate (NAA) was the first MRS-based marker of metastasis growth in the brain (micrometastasis); choline-containing compounds (Cho) rose and creatine (Cr) levels decreased as these lesions evolved, with mobile lipids and lactate also becoming visible. Furthermore, MRS pattern recognition-based analysis suggested that this approach may help to discriminate different growth stages. CONCLUSIONS: This study paves the way for further in vivo studies oriented towards detection of different tumor progression states and for improving treatment efficiency.     

BMP9-Induced Survival Effect in Liver Tumor Cells Requires p38MAPK Activation

The study of bone morphogenetic proteins (BMPs) role in tumorigenic processes, and specifically in the liver, has gathered importance in the last few years. Previous studies have shown that BMP9 is overexpressed in about 40% of hepatocellular carcinoma (HCC) patients. In vitro data have also shown evidence that BMP9 has a pro-tumorigenic action, not only by inducing epithelial to mesenchymal transition (EMT) and migration, but also by promoting proliferation and survival in liver cancer cells. However, the precise mechanisms driving these effects have not yet been established. In the present work, we deepened our studies into the intracellular mechanisms implicated in the BMP9 proliferative and pro-survival effect on liver tumor cells. In HepG2 cells, BMP9 induces both Smad and non-Smad signaling cascades, specifically PI3K/AKT and p38MAPK. However, only the p38MAPK pathway contributes to the BMP9 growth-promoting effect on these cells. Using genetic and pharmacological approaches, we demonstrate that p38MAPK activation, although dispensable for the BMP9 proliferative activity, is required for the BMP9 protective effect on serum withdrawal-induced apoptosis. These findings contribute to a better understanding of the signaling pathways involved in the BMP9 pro-tumorigenic role in liver tumor cells.     

Usage,content and citation in open access publication: any interaction effects?

Scientometrics - This study aims to validate an empirical model, at document level, that explains the interaction among content, usage, and citation within open access publications. The...