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31.
Molecular Biology Reports - Hsa-mir-143 and hsa-let-7c have been reported to be deregulated in multiple neoplasms. The main purpose of this study was to investigate the expression of these miRNAs...  相似文献   
32.
In severe cases of sepsis, endotoxin-induced cardiomyopathy can cause major damage to the heart. This study was designed to see if Vitamin C (Vit C) could prevent lipopolysaccharide-induced heart damage. Eighteen Sprague Dawley male rats (n = 6) were divided into three groups. Rats received 0.5 mL saline by oral gavage in addition to a standard diet (Control group), rats received one dose of endotoxin on day 15 (lipopolysaccharide) (LPS) (6 mg/kg), which produced endotoxemia (Endotoxin group), and rats that received 500 mg/Kg BW of Vit C by oral gavage for 15 days before LPS administration (Endotoxin plus Vit C group). In all groups, blood and tissue samples were collected on day 15, six hours after LPS administration, for histopathological and biochemical analysis. The LPS injection lowered superoxide dismutase (SOD) levels and increased malondialdehyde in tissues compared with a control group. Furthermore, the endotoxin group showed elevated inflammatory biomarkers, tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). Both light and electron microscopy showed that the endotoxic-treated group’s cardiomyocytes, intercalated disks, mitochondria, and endothelial cells were damaged. In endotoxemic rats, Vit C pretreatment significantly reduced MDA levels and restored SOD activity, minimized biomarkers of inflammation, and mitigated cardiomyocyte damage. In conclusion: Vit C protects against endotoxin-induced cardiomyopathy by inhibiting oxidative stress cytokines.  相似文献   
33.
The purpose of this study was to identify the chemical composition and the antibacterial activity of the essential oils (EOs) extracted from the green tops of Daucus carota L. subsp. sativus (Hoffm .) Arcang. plants producing yellow roots (DcsYR) and those producing orange roots (DcsOR) and from two varieties of Foeniculum vulgare subsp. vulgare cultivated in Tunisia. Analyses revealed that the EOs from the two D. carota varieties were rich in constituents belonging to sesquiterpenes. Phenylpropanoids and non‐terpene derivatives were the most abundant classes of compounds in the EOs from the two varieties of F. vulgare, of which compositions were predominated by (E)‐anethole and p‐acetonylanisole. All the tested EOs were significantly more effective against Gram‐negative bacteria, and that obtained from var. azoricum was more active against the yeast Candida albicans than the reference drug. The EOs obtained from these by‐products showed indeed interesting potential to be promoted as natural antimicrobials in food preservation systems, as well as the possibility to be used in flavor industries.  相似文献   
34.

Background

Given the high occurrence of prostate cancer worldwide and one of the major sources of the discovery of new lead molecules being medicinal plants, this research undertook to investigate the possible anti-cancer activity of two natural cycloartanes; cycloartane-3,24,25-diol (extracted in our lab from Tillandsia recurvata) and cycloartane-3,24,25-triol (purchased). The inhibition of MRCKα kinase has emerged as a potential solution to restoring the tight regulation of normal cellular growth, the loss of which leads to cancer cell formation.

Methods

Kinase inhibition was investigated using competition binding (to the ATP sites) assays which have been previously established and authenticated and cell proliferation was measured using the WST-1 assay.

Results

Cycloartane-3,24,25-triol demonstrated strong selectivity towards the MRCKα kinase with a Kd50 of 0.26 μM from a total of 451 kinases investigated. Cycloartane-3,24,25-triol reduced the viability of PC-3 and DU145 cell lines with IC50 values of 2.226?±?0.28 μM and 1.67?±?0.18 μM respectively.

Conclusions

These results will prove useful in drug discovery as Cycloartane-3,24,25-triol has shown potential for development as an anti-cancer agent against prostate cancer.  相似文献   
35.
Gene duplication followed by functional specialization is a potent force in the evolution of biological diversity. A comparative study of two highly conserved duplicated genes, ARABIDOPSIS TRITHORAX-LIKE PROTEIN1 (ATX1) and ATX2, revealed features of both partial redundancy and of functional divergence. Although structurally similar, their regulatory sequences have diverged, resulting in distinct temporal and spatial patterns of expression of the ATX1 and ATX2 genes. We found that ATX2 methylates only a limited fraction of nucleosomes and that ATX1 and ATX2 influence the expression of largely nonoverlapping gene sets. Even when coregulating shared targets, ATX1 and ATX2 may employ different mechanisms. Most remarkable is the divergence of their biochemical activities: both proteins methylate K4 of histone H3, but while ATX1 trimethylates it, ATX2 dimethylates it. ATX2 and ATX1 provide an example of separated K4 di from K4 trimethyltransferase activity.  相似文献   
36.
The purpose of the study was to obtain more reliable epidemiological data concerning Entamoeba (E.) histolytica infection in Tunisian food handlers using established molecular tools able to differentiate E. histolytica from E. dispar. From 2002 to 2005, 4,266 fresh stools specimens received in the setting of the National program of food handlers' control were analysed by optical microscopy. Twelve (2.8 per thousand) were positive for the presence of four nuclei cysts identified as E. histolytica/E. dispar. Extraction of DNA from the 12 samples, followed by specific amplifications of E. histolytica and E. dispar SSU rDNA, showed that 11 samples (92%) were positive for E. dispar and negative for E. histolytica. Sequencing analysis of 8 PCR products permitted to verify the results obtained with conventional PCR. The remaining sample was negative by PCR amplifying E. histolytica DNA or E. dispar DNA specifically, although it did not show any inhibition. It probably contains protozoan cysts genetically distinct from these two species but morphological similar. Estimation of relative proportions between E. histolytica and E. dispar in cyst carriers showed that all explored individuals harboured the non pathogenic E. dispar strains. This result highlights the need of use in this population of complementary tests that allow specific diagnosis and obviate unnecessary chemotherapy.  相似文献   
37.
38.
K Ayed  Y Gorgi 《Human heredity》1990,40(6):363-367
The C3, BF, C4A and C4B polymorphisms were studied in a Tunisian population sample. The allelic frequencies for C3 were S = 0.844 and F = 0.148, and for BF, S = 0.535, F = 0.331, SO7 = 0.075 and F1 = 0.041. The most frequent C4 alleles were A3 and B1 followed in a decreasing order by A2, B2 and the A and B null alleles. The results indicate that the Tunisian population is intermediate between the Caucasian and Arab populations with some trace admixture of African Blacks.  相似文献   
39.
BACKGROUND: Metastases to the breast are rare and can be missed without knowledge of the clinical history. We report an unusual breast metastasis originating in an olfactory neuroblastoma. CASE: A breast metastasis from esthesioneuroblastoma occurred in a 20-year-old woman 2 years after the onset of the disease. The aspirates were hypercellular and composed of cellular aggregates and single cells with a monomorphic appearance. The cytoplasm was scanty and inconspicuous. The nucleus was large, with granular, hyperchromatic chromatin. Mitoses and apoptotic bodies were numerous. Because we were unaware of the past history at the time of the cytologic analysis, a definitive diagnosis was made only after pathologic study. CONCLUSION: Esthesioneuroblastoma metastatic to the breast must be considered in the differential diagnosis of breast metastases. Fine needle aspiration, in conjunction with clinical information, can be effective in the diagnosis of esthesioneuroblastoma metastatic to the breast.  相似文献   
40.
The results of previous studies conducted at the University of Hohenheim and the International Center for Agricultural Research in the Dry Areas (ICARDA) indicated that the yielding ability and stability of barley (Hordeum vulgare L.) could be improved in environments with drought stress by increasing the level of heterozygosity. This would require increasing the outbreeding rate of locally adapted breeding materials. As a first step, we estimated the outcrossing rate of 12 barley landraces (Hordeum vulgare ssp. vulgare, in short H. vulgare) and 13 sympatrically occurring populations of its wild progenitor [Hordeum vulgare ssp. spontaneum (C. Koch), in short H. spontaneum] collected from semi-arid localities in Jordan during the 1999/2000 growing season. In each H. vulgare or H. spontaneum population 28–48 spikes were sampled, and up to six offspring (seeds) per spike (called a family) were used for PCR analyses. Collection sites covered high–low transects for rainfall and altitude in order to detect possible environmental effects on the outcrossing rate. Four microsatellite markers located on different chromosomes were used to genotype the samples for estimating the outcrossing rate. Low season-specific multilocus outcrossing rates (tm) were found in both cultivated and wild barley, ranging among populations from 0–1.8% with a mean of 0.34%. Outcrossing rates based on inbreeding equilibrium (te), indicating outcrossing averaged across years, were two- to threefold higher than the season-specific estimates. Under high rainfall conditions somewhat higher—though not significantly higher—outcrossing rates were observed in H. spontaneum than in H. vulgare. The season-specific outcrossing rate in H. spontaneum was positively correlated (r=0.67, P=0.01) with average annual precipitation and negatively correlated (r=0.59, P=0.05) with monthly average temperature during flowering. The results suggest that outcrossing may vary considerably among seasons and that high precipitation and cool temperatures during flowering tend to enhance outcrossing. The rather low levels of outcrossing detected indicate that increased vigour due to heterozygosity has not been a major fitness advantage in the evolution and domestication of H. spontaneum and H. vulgare, respectively. Stable seed production to secure survival under extreme heat and drought stress may have been more important. Cleistogamy may be considered as an effective mechanism to warrant pollination even in drought-stunted plants with non-extruding spikes.  相似文献   
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