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391.
Zinc has a role in the synthesis, storage, and secretion of insulin, and has been suggested to be beneficial when used in the diabetic state. Effect of zinc intake in pregnant rats has been studied here on diabetized offspring. Pregnant rats were divided in two groups; the control group received normal food and water, and the experimental group received zinc sulfate during pregnancy and 3 weeks after offspring birth. Male offspring from the control (C) and experimental (E) groups were divided each in three groups: C1, fed with normal food and water; C2, diabetized with alloxan; C3, received zinc sulfate; E1, fed with normal food and water; E2, diabetized with alloxan; and E3, receiving zinc sulfate. After 30 days, the histological changes of pancreatic tissues were investigated by light microscopy. Body weight, blood glucose, serum insulin levels, food intake, water intake, and urine quantity were also compared between the groups. Water intake and urine quantity were decreased significantly (p?<?0.01and p?<?0.001) in E2 (experimental diabetic group) in comparison with C2 (control diabetic group), but there was no significant difference in the body weight in C2 in comparison with E2, while blood glucose was decreased significantly (p?<?0.001) and blood insulin level was increased significantly (p?<?0.01) in E2 in comparison with C2. Microscopic evaluation of pancreas showed that E2 were protected against alloxan-induced beta-cell degeneration. In conclusion, this work showed that maternal zinc intake may influence subsequent deleterious effects of diabetes on alloxan-diabetized offspring.  相似文献   
392.
The essential oil of Ajuga pseudoiva, collected from Tunisia, was analyzed using gas chromatography–mass spectroscopy. Thirty-two compounds accounting for 95.76% of the total oil were identified. Sesquiterpenes were found to be the most abundant components of A. pseudoiva oil. And they were mainly represented by viridiflorol (30.17%), germacrene B (9.26%) (α, β and γ)-eudesmol (8.11%) and aromadendrene (7.45%). The essential oil of A. pseudoiva showed radical scavengers activity (IC50 = 0.72 mg/mL) and displayed lipid peroxidation inhibitory activity (IC50 = 0.6 mg/mL). A. pseudoiva essential oil was also found to exhibit a dose-dependent ACE inhibitory activity with an IC50 value of 65.5 μg/mL. Moreover, the antimicrobial activity of the essential oil was tested against 17 species of microorganisms, and the results obtained showed significant antibacterial activity against the Gram-positive and Gram-negative bacteria, with inhibition zones and minimal inhibitory concentration values of 14–32 mm and 84–137 μg/mL and 6–21 mm and 105–336 μg/mL, respectively. Higher activity was also found against several fungal strains.  相似文献   
393.
394.
Twenty three dual PPARα and γ molecules of natural product origin, previously reported by our group, were further investigated for pan PPAR transactivation against PPARδ. The in vitro cell toxicity profile, as well as, in silico study of the most active molecules within this new class of pan PPAR agonists are also described. 3′,5′ Dimethoxy-7 hydroxyisoflavone 6, Ψ-baptigenin 7, 4′ fluoro-7 hydroxyisoflavone 8, and 3′ methoxy-7 hydroxyisoflavone 9 were identified as the most potent molecules studied within the set compared to the commercially available pan PPAR agonist, bezafibrate 1. These novel active molecules may thus be useful as future leads in PPAR-related disorders, including type II diabetes mellitus and metabolic syndrome.  相似文献   
395.

BACKGROUND:

Mental retardation (MR) has a prevalence of 1-3% and genetic causes are present in more than 50% of patients. Chromosomal abnormalities are one of the most common genetic causes of MR and are responsible for 4-28% of mental retardation. However, the smallest loss or gain of material visible by standard cytogenetic is about 4 Mb and for smaller abnormalities, molecular cytogenetic techniques such as array comparative genomic hybridization (array CGH) should be used. It has been shown that 15-25% of idiopathic MR (IMR) has submicroscopic rearrangements detectable by array CGH. In this project, the genomic abnormalities were investigated in 32 MR patients using this technique.

MATERIALS AND METHODS:

Patients with IMR with dysmorphism were investigated in this study. Karyotype analysis, fragile X and metabolic tests were first carried out on the patients. The copy number variation was then assessed in a total of 32 patients with normal results for the mentioned tests using whole genome oligo array CGH. Multiple ligation probe amplification was carried out as a confirmation test.

RESULTS:

In total, 19% of the patients showed genomic abnormalities. This is reduced to 12.5% once the two patients with abnormal karyotypes (upon re-evaluation) are removed.

CONCLUSION:

The array CGH technique increased the detection rate of genomic imbalances in our patients by 12.5%. It is an accurate and reliable method for the determination of genomic imbalances in patients with IMR and dysmorphism.  相似文献   
396.
Acetylcholine (ACh), the classical neurotransmitter, also affects a variety of nonexcitable cells, such as endothelia, microglia, astrocytes and lymphocytes in both the nervous system and secondary lymphoid organs. Most of these cells are very distant from cholinergic synapses. The action of ACh on these distant cells is unlikely to occur through diffusion, given that ACh is very short-lived in the presence of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), two extremely efficient ACh-degrading enzymes abundantly present in extracellular fluids. In this study, we show compelling evidence for presence of a high concentration and activity of the ACh-synthesizing enzyme, choline-acetyltransferase (ChAT) in human cerebrospinal fluid (CSF) and plasma. We show that ChAT levels are physiologically balanced to the levels of its counteracting enzymes, AChE and BuChE in the human plasma and CSF. Equilibrium analyses show that soluble ChAT maintains a steady-state ACh level in the presence of physiological levels of fully active ACh-degrading enzymes. We show that ChAT is secreted by cultured human-brain astrocytes, and that activated spleen lymphocytes release ChAT itself rather than ACh. We further report differential CSF levels of ChAT in relation to Alzheimer’s disease risk genotypes, as well as in patients with multiple sclerosis, a chronic neuroinflammatory disease, compared to controls. Interestingly, soluble CSF ChAT levels show strong correlation with soluble complement factor levels, supporting a role in inflammatory regulation. This study provides a plausible explanation for the long-distance action of ACh through continuous renewal of ACh in extracellular fluids by the soluble ChAT and thereby maintenance of steady-state equilibrium between hydrolysis and synthesis of this ubiquitous cholinergic signal substance in the brain and peripheral compartments. These findings may have important implications for the role of cholinergic signaling in states of inflammation in general and in neurodegenerative disease, such as Alzheimer’s disease and multiple sclerosis in particular.  相似文献   
397.
Naturally occurring polyamines are known to interact with a variety of biomolecules and critically involve in some important physiological processes. They have also been shown to influence protein aggregation in vitro in some cases. The aim of the present study was to investigate how polyamines may influence the structure and thermal stability of alpha-chymotrypsin and modulate alcohol-induced aggregation of this protein. Various techniques, including turbidity measurements, tensiometry, DSC, intrinsic fluorescence and far- and near-UV circular dichroism spectroscopy were used to examine the effect of putrescine and spermidine on alpha-chymotrypsin. While slight changes in the secondary and tertiary structure of the protein was observed, a clear stabilizing effect against its thermal unfolding was achieved. Moreover, the polyamines were found to inhibit TFE-induced aggregation at 32% TFE and promote formation of non-native alpha-helices in the protein structure. Based on the observed increase in surface tension induced by polyamines, it is suggested that their effects on enhancing thermal stability and alcohol-induced alpha-helices formation may be due to their kosmotropic properties.  相似文献   
398.
While searching for food, predators may use volatiles associated with their prey, but also with their competitors for prey. This was tested for the case of Zetzellia mali (Ewing) (Acari: Stigmaeidae), an important predator of the hawthorn spider mite, Amphitetranychus viennensis (Zacher) (Acari: Tetranychidae), in black-cherry orchards in Baraghan, Iran. Using a Y-tube olfactometer, the response of this predatory mite was tested to odour from black-cherry leaves with a conspecific female predatory mite, either with or without a female of the hawthorn spider mite when the alternative odour came from black-cherry leaves with the hawthorn spider mite only. Female predators avoided odours from leaves with both a hawthorn spider mite and a conspecific predator, as well as leaves with a conspecific predator only. We discuss whether avoidance emerges in response to cues from the competitor/predator, the herbivore/prey or the herbivore-damaged plant.  相似文献   
399.
Argyrops spinifer and Rhabdosargus haffara are two sympatric seabream species making important contributions to fisheries landings in the western Arabian/Persian Gulf. We identified the strengths and weaknesses in the long-term sustainability of A. spinifer and R. haffara stocks by integrating multiple sources of data, including fisheries catch and effort statistics, life history traits, scientific trawl surveys and historical length frequency distribution. Four strengths were identified in A. spinifer: wide distribution of juveniles, positive association to the network of de facto fishing exclusion areas created by hundreds of oil-gas facilities, early maturation and the existence of large and old individuals. A. spinifer suffers from two potential weaknesses: slow growth rate and higher exploitation pressure on the small-sized individuals. R. haffara, on the other hand, has a strength of having a short life span and a fast growth rate, characteristics that make it robust to unfavourable conditions. R. haffara suffers from two weaknesses: the lack of association to the oil and gas facilities, and the preference for nearshore shallow waters with stronger negative anthropogenic impacts. Identified strengths and weaknesses of these two sparids provided a preliminary assessment about their long-term sustainability, as well as a roadmap about how to develop different management strategies to meet specific objectives.  相似文献   
400.
Molecular Biology Reports - Inflammatory bowel disease (IBD) is considered a chronic inflammatory gastrointestinal disease with treatment options which exhibit low efficacies and lead to...  相似文献   
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