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874.
Amna Al-Otaiba Annie John Thekra Al-Belooshi Haider Raza 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2010,180(8):1121-1132
We have previously reported the occurrence of multiple forms of drug-metabolizing enzymes in camel tissues. Here, we investigate
glutathione (GSH)-dependent redox homeostasis, reactive oxygen species (ROS) production and mitochondrial respiratory functions
in camel tissues and compare them with imported domestic goats and laboratory rats and mice. Cytochrome P450 2E1 (CYP 2E1)
and GSH-metabolizing enzymes were differentially expressed in the liver and kidney of these animals. Camel liver has significantly
lower GSH pool than that in goats, rats and mice. Mitochondria isolated from the tissues of these animals showed a comparable
ability to metabolize specific substrates for respiratory enzyme complexes I, II/III and IV. These complexes were metabolically
more active in the kidney than in the liver of all the species. Furthermore, the activity of complex IV in camel tissues was
significantly lower than in other species. On the other hand, complex II/III activity in camel kidney was higher compared
to the other species. In addition, as expected, we observed that inhibitors of these enzyme complexes augment the production
of mitochondrial ROS in camel and goat tissues. These results help to better understand the metabolic ability and adaptation
in desert camels in comparison with domestic goats and laboratory rats and mice since they are exposed to different environmental
and dietary conditions. Our study may also have implications in the pharmacology and toxicology of drugs and pollutants in
these species. 相似文献
875.
Fatma Bensassi Ali Rhouma Mohamed Ghrab Hassen Bacha Mohamed Rabeh Hajlaoui 《Mycotoxin Research》2010,26(3):199-203
Aflatoxins (AFs) are potent sources of health risks to both humans and animals. Among them, AFB1 is the most hazardously toxic
and the most frequent in various food commodities, including pistachio nuts. In this survey, the effect of the storage period
on AFB1 accumulation on pistachio nuts was investigated. A total of 49 samples collected during the crop year of 2005 from
the most cultivated pistachio cultivars in Tunisia were rapidly screened by enzyme-linked immunosorbent assay (ELISA) combined
with an immunoaffinity step. The obtained results showed that the contamination of pistachio nuts has occurred clearly after
two years of storage for all the tested cultivars except the case of Mateur variety and Thyna ecotypes. In this study, the
cultivar Mateur was found to be the most susceptible cultivar to contamination by AFB1. After 4 years of storage, the average
contamination levels in nut samples ranged from 2.7 ± 0.3 to 12.7 ± 2.2 μg/kg for AFB1, according to the cultivar. These levels
exceeded the maximum permitted limit of 2 μg/kg set by the European Commission in nuts. 相似文献
876.
Sefa Gulturk Ayse Demirkazik Ilkay Kosar Ali Cetin Hatice S. Dökmetas Tuncer Demir 《Bioelectromagnetics》2010,31(4):262-269
We investigated the effect of long‐term exposure to modulation magnetic field (MF), insulin, and their combination on blood–brain barrier (BBB) permeability in a diabetic rat model. Fifty‐three rats were randomly assigned to one of six groups: sham, exposed to no MF; MF, exposed to MF; diabetes mellitus (DM), DM induced with streptozotocin (STZ); DM plus MF (DMMF); DM plus insulin therapy (DMI); and DM plus insulin therapy plus MF (DMIMF). All the rats underwent Evans blue (EB) measurement to evaluate the BBB 30 days after the beginning of experiments. The rats in MF, DMMF, and DMIMF groups were exposed to MF (B = 5 mT) for 165 min every day for 30 days. Mean arterial blood pressure (MABP), body mass, and serum glucose level of the study rats were recorded. The extravasation of brain EB of the MF, DM, DMMF, DMI, and DMIMF groups was higher than that of the sham group and the extravasation of right hemisphere of the DMIMF group was highest (P < 0.05). The post‐procedure body mass of the sham and MF groups were significantly higher than those of the DM and DMMF groups (P < 0.05). In the DM, DMMF, DMI, and DMIMF groups, the baseline glucose was significantly lower than the post‐procedure glucose (P < 0.05). DM and MF increase BBB permeability; in combination, they cause more increase in BBB permeability, and insulin decreases their effect on BBB. Improved glucose metabolism may prevent body mass loss and the hypoglycemic effect of MF. DM increases MABP but MF causes no additional effect. Bioelectromagnetics 31:262–269, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
877.
Accumulations of higher inositol polyphosphates, diphosphoinositol polyphosphates or pyrophosphates, have been implicated to mediate cellular apoptosis. Whether cellular levels of lower inositol phosphates (lower than inositol hexakisphosphates) change during apoptosis is not known, although these inositol phosphates are known to play crucial roles in a number of cellular signaling processes including calcium mobilization. Therefore, in this study, we have examined changes in cellular levels of inositol phosphates following metabolic labeling of these compounds by [3H]myo-inositol and induction of apoptosis. The levels of inositol mono- and bis-phosphates were increased, whereas the levels of inositol tris- and tetrakis-phosphates decreased significantly with an increasing rate of apoptosis induced by etoposide in a dose-dependent manner. NaF treatment, which increased the rate of apoptosis in a time- and dose-dependent manner, also increased the levels of inositol mono- and bis-phosphates and drastically reduced the levels of inositol tris- and tetrakis-phosphates. Prior treatment with antimycin A, a strategy used to reverse the NaF-induced accumulations of higher InsPs, partially reduced the effects of NaF on apoptosis as well as the levels of lower InsPs. Taken together, our results suggest that cellular levels of lower InsPs are altered during apoptosis. 相似文献
878.
Thorium-232 (232Th), a natural radionuclide from the actinide family, is abundantly present in monazite and other ores. It is used as one of the prime fuel materials in nuclear industry and may pose an exposure risk to nuclear workers and members of the public. Human erythrocytes, as a classical cellular membrane model, were coincubated with 232Th in order to elucidate whether this naturally occurring important radionuclide produced perturbations to cell membrane. Present study revealed that erythrocytes underwent aggregation or lysis depending on the ratio of 232Th to cell. Scanning electron micrographs showed that erythrocytes transformed into equinocytes and/or spherocytes after 232Th treatment. Further examination of erythrocyte by atomic force microscopy suggested significant increase in surface roughness after 232Th treatment. Experiments on neuraminidase treated and/or anti-GpA antibody blocked erythrocytes suggested significant role of membrane sialic acid and glycophorin A (GpA) protein in aggregation or hemolytic effects of 232Th. Further results showed that 232Th caused hemolysis by colloid osmotic mechanism, as evidenced by potassium efflux, osmotic protection and osmotic fragility studies. Osmoprotection experiments indicated that hemolysis get elicited through the formation of membrane pores of ∼2.0 nm in size. Hemolysis studies in presence of inhibitors (TEA, bumetanide, DIDS and amiloride) revealed the role of K+ channel, Na+/K+/2Cl− channel, Cl−/HCO3− anion exchanger and Na+/H+ antiporter in 232Th induced erythrolysis. Presence of non-diffusible cation (N-methyl d-glucasamine) or anion (gluconate) in erythrocyte suspending medium further confirm the role of Na+ and Cl− influx in hemolytic effect of 232Th. These findings provide significant insight in structural, biochemical and osmotic toxic effects of 232Th on human erythrocytes. 相似文献
879.
Abolghasem Abbasi Kejani Sayed Ali Hosseini Tafreshi Sayed Mojtaba Khayyam Nekouei Mohammad Reza Mofid 《Molecular biology reports》2010,37(2):797-800
Improved and efficient methods were developed for isolating high quality DNA and RNA from different sources of Iranian Yew
(Taxus baccata L.). The methods were based on CTAB extraction buffer added with high levels of polyvinylpyrrolidone (PVP) and β-mercaptoethanol to properly remove polysaccharides and prevent oxidation of phenolics. The pellets obtained by ethanol precipitation
were washed only with Chloroform: isoamyl alcohol (24:1). So, we could successfully eliminate the dangerous phenol/chloroform
extraction steps from the isolation procedure. Both spectrophotometric (A260/A280 and A260/A230 ratios) and agarose electrophoresis analysis of isolated nucleic acids (DNA and RNA) indicated good results. DNA with the
average yield of 100–300 μg/g leaf and stem tissue and total RNA with an average yield of 20–30 μg/g cell culture and 80–100 μg/g
leaf and stem tissue of Iranian yew could be obtained. Successful amplification of pam and pds by PCR and RT-PCR, showed the integrity of isolated DNA and RNA, respectively. 相似文献
880.
Muhammad Ajmal Waqas Ahmed Ahmed Sadeque Syeda Hafiza Benish Ali Syed Habib Bokhari Nuzhat Ahmed Raheel Qamar 《Molecular biology reports》2010,37(8):3869-3875
Familial Hypercholesterolemia (FH) results in elevated levels of blood lipids including total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) with normal triglycerides (TG). This disease is one of the major contributors towards an early onset of coronary heart disease (CHD). The aim of the present study was to identify the genes responsible for causing FH in Pakistani population, for this purpose a large consanguineous FH family was selected for genetic analysis. Serum lipid levels, including TC, TG, LDL-C and high density lipoprotein cholesterol (HDL-C), were determined in patients and healthy controls. In order to find the causative mutation in this family, direct sequencing of the low density lipoprotein receptor (LDLR) gene was performed. In addition the part of the Apolipoprotein-B (APOB) gene containing the mutations R3500Q and R3500W was also sequenced. Affected individuals of the family were found to have raised TC and LDL-C levels. Sequencing revealed an insertion mutation (c.2416_2417InsG) in exon 17 of the LDLR gene in all the affected individuals of the family. Common FH causing APOB mutations were not present in this family. Heterozygous individuals had TC levels ranging from ~300–500 mg/dl and the only homozygous individual with typical xanthomas had TC levels exceeding 900 mg/dl. This is the first report of a known LDLR gene mutation causing FH in the Pakistani population. Despite a large heterogeneity of LDLR mutations there are still some common mutations which are responsible for FH throughout the world. 相似文献