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91.
Valuable effects of gold particles have been reported and used in complementary medicine for decades. The aim of this study was to evaluate the therapeutic efficacy of gold nanoparticles (AuNPs) against acetaminophen (APAP) induced toxicity. Albino rats were administered APAP at a dose of 2 g/kg p.o. once only. After 24 h of APAP intoxication, animals were treated with three different doses of AuNPs (50 μg/kg, 100 μg/kg, 150 μg/kg) orally or silymarin at a dose of 50 mg/kg p.o., once only. Animals of all the groups were sacrificed after 24 h of last treatment. APAP administered group showed a significant rise in the AST, ALT, SALP, LDH, cholesterol, bilirubin, albumin, urea and creatinine in serum which indicated the hepato-renal damage. A significantly enhanced LPO and a depleted level of GSH were observed in APAP intoxicated rats. Declined activities of SOD and Catalase, after acetaminophen exposure indicated oxidative stress in liver and kidney. The activities of ATPase and glucose-6-Phosphatase were significantly inhibited after APAP administration. AuNPs treatment reversed all variables significantly towards normal level and was found nontoxic. Thus it is concluded that gold nanoparticles played a beneficial role in reducing acetaminophen induced toxicity and can be used in the development of drug against hepatic as well as renal diseases, after further preclinical and clinical studies.  相似文献   
92.
SYBR Green I real-time PCR was developed for detection and differentiation of Newcastle disease virus (NDV). Primers based on the nucleocapsid (NP) gene were designed to detect specific sequence of velogenic strains and lentogenic/vaccine strains, respectively. The assay was developed and tested with NDV strains which were characterized previously. The velogenic strains were detected only by using velogenic-specific primers with a threshold cycle (Ct) 18.19 ± 3.63 and a melting temperature (Tm) 86.0 ± 0.28 °C. All the lentogenic/vaccine strains, in contrast, were detected only when lentogenic-specific primers were used, with the Ct value 14.70 ± 2.32 and Tm 87.4 ± 0.21 °C. The assay had a dynamic detection range which spans over a 5 log10 concentration range, 109–105 copies of DNA plasmid/reaction. The velogenic and lentogenic amplifications showed high PCR efficiency of 100% and 104%, respectively. The velogenic and lentogenic amplifications were highly reproducible with assay variability 0.45 ± 0.31% and 1.30 ± 0.65%, respectively. The SYBR Green I real-time PCR assay detected successfully the virus from tissue samples and oral swabs collected from the velogenic and lentogenic NDV experimental infection, respectively. In addition, the assay detected and differentiated accurately NDV pathotypes from suspected field samples where the results were in good agreement with both virus isolation and analysis of the fusion (F) cleavage site sequence. The assay offers an attractive alternative method for the diagnosis of NDV.  相似文献   
93.

OBJECTIVES:

The aim of this study was to determine the antiproliferative and apoptotic effects of hot water extracts of Chlorella vulgaris on hepatoma cell line HepG2.

INTRODUCTION:

The search for food and spices that can induce apoptosis in cancer cells has been a major study interest in the last decade. Chlorella vulgaris, a unicellular green algae, has been reported to have antioxidant and anti‐cancer properties. However, its chemopreventive effects in inhibiting the growth of cancer cells have not been studied in great detail.

METHODS:

HepG2 liver cancer cells and WRL68 normal liver cells were treated with various concentrations (0‐4 mg/ml) of hot water extract of C. vulgaris after 24 hours incubation. Apoptosis rate was evaluated by TUNEL assay while DNA damage was assessed by Comet assay. Apoptosis proteins were evaluated by Western blot analysis.

RESULTS:

Chlorella vulgaris decreased the number of viable HepG2 cells in a dose dependent manner (p < 0.05), with an IC50 of 1.6 mg/ml. DNA damage as measured by Comet assay was increased in HepG2 cells at all concentrations of Chlorella vulgaris tested. Evaluation of apoptosis by TUNEL assay showed that Chlorella vulgaris induced a higher apoptotic rate (70%) in HepG2 cells compared to normal liver cells, WRL68 (15%). Western blot analysis showed increased expression of pro‐ apoptotic proteins P53, Bax and caspase‐3 in the HepG2 cells compared to normal liver cells WRL68, and decreased expression of the anti‐apoptotic protein Bcl‐2.

CONCLUSIONS:

Chlorella vulgaris may have anti‐cancer effects by inducing apoptosis signaling cascades via an increased expression of P53, Bax and caspase‐3 proteins and through a reduction of Bcl‐2 protein, which subsequently lead to increased DNA damage and apoptosis.  相似文献   
94.
Methylenetetrahydrofolate (MTHFR) and DNMT3b play imperative roles in DNA synthesis and de novo methylation. GSTM1 is involved in detoxification of carcinogens. Mitochondrial DNA deletion has been associated with lower motility in human sperm. We analysed if polymorphisms in MTHFR (C677T and A1298C) and DNMT3b (C46359T) are associated with non-obstructive male infertility. We also analysed if folate, vitamin B(12), homocysteine (Hcy), 8'-hydroxy-2'-deoxygnanosine (8-OHdG) levels, dietary folate intake and mtDNA deletion (4977 bp) affects fertility, such interactions are modified by deletion and methylation of GSTM1. In this case-control study, we included 179 oligoasthenoteratozoospermia patients and 200 fertile men. Single-nucleotide polymorphism analysis was performed by PCR-restriction fragment length polymorphism. The MTHFR (C677T and A1298C) and DNMT3b (C46359T) frequencies did not differ significantly in two groups. GSTM1 in association with mtDNA 4977 deletion is significantly associated with infertility. Plasma folate and vitamin B(12) levels are decreased and total Hcy is elevated in infertile men. GSTM1 methylation status was investigated by methylation-specific PCR. Methylation is significantly correlated with GSTM1 reduced/loss of expression in infertile men. Infertile men have significantly higher 8-OHdG levels. Dietary folate intake is not linked with GSTM1 methylation. Low folate intake in association with CT + TT genotypes (C677T) has significant protective effect on GSTM1 methylation. Results indicate that micronutrients, 8-OHdG levels, mtDNA deletion and GSTM1 promoter methylation are frequent alterations in infertility.  相似文献   
95.
Formalin fixed and paraffin embedded tissue (FFPE) collections in pathology departments are the largest resource for retrospective biomedical research studies. Based on the literature analysis of FFPE related research, as well as our own technical validation, we present the Translational Research Arrays (TRARESA), a tissue microarray centred, hospital based, translational research conceptual framework for both validation and/or discovery of novel biomarkers. TRARESA incorporates the analysis of protein, DNA and RNA in the same samples, correlating with clinical and pathological parameters from each case, and allowing (a) the confirmation of new biomarkers, disease hypotheses and drug targets, and (b) the postulation of novel hypotheses on disease mechanisms and drug targets based on known biomarkers. While presenting TRARESA, we illustrate the use of such a comprehensive approach. The conceptualisation of the role of FFPE-based studies in translational research allows the utilisation of this commodity, and adds to the hypothesis-generating armamentarium of existing high-throughput technologies.  相似文献   
96.

OBJECTIVE:

Dark poly(caprolactone) trifumarate is a successful candidate for use as a bone tissue engineering scaffold. Recently, a white polymeric scaffold was developed that shows a shorter synthesis time and is more convenient for tissue-staining work. This is an in vitro comparative study of both the white and dark scaffolds.

METHODS:

Both white and dark poly(caprolactone) trifumarate macromers were characterized via Fourier transform infrared spectroscopy before being chemically cross-linked and molded into disc-shaped scaffolds. Biodegradability was assessed by percentage weight loss on days 7, 14, 28, 42 and 56 (n = 5) after immersion in 10% serum-supplemented medium or distilled water. Static cell seeding was employed in which isolated and characterized rat bone marrow stromal cells were seeded directly onto the scaffold surface. Seeded scaffolds were subjected to a series of biochemical assays and scanning electron microscopy at specified time intervals for up to 28 days of incubation.

RESULTS:

The degradation of the white scaffold was significantly lower compared with the dark scaffold but was within the acceptable time range for bone-healing processes. The deoxyribonucleic acid and collagen contents increased up to day 28 with no significant difference between the two scaffolds, but the glycosaminoglycan content was slightly higher in the white scaffold throughout 14 days of incubation. Scanning electron microscopy at day 1 revealed cellular growth and attachment.

CONCLUSIONS:

There was no cell growth advantage between the two forms, but the white scaffold had a slower biodegradability rate, suggesting that the newly synthesized poly(caprolactone) trifumarate is more suitable for use as a bone tissue engineering scaffold.  相似文献   
97.
Thalassaemia is a public health problem in Malaysia, with each ethnic group having their own common mutations. However, there is a lack on data on the prevalence and common mutations among the indigenous people. This cross‐sectional study was performed to determine the common mutations of α‐ and β‐thalassaemia among the subethnic groups of Senoi, the largest Orang Asli group in Peninsular Malaysia. Blood samples collected from six Senoi subethnic groups were analysed for full blood count and haemoglobin analysis (HbAn). Samples with abnormal findings were then screened for α‐ and β‐globin gene mutations. Out of the 752 samples collected, 255 showed abnormal HbAn results, and 122 cases showing abnormal red cell indices with normal HbAn findings were subjected to molecular screening. DNA analysis revealed a mixture of α‐ and β‐globin gene mutations with 25 concomitant cases. The types of gene abnormalities detected for α‐thalassaemia were termination codon (T>C) Hb CS (αCSα), Cd59 (G>A) haemoglobin Adana (Hb Adana) (αCd59α), initiation codon (ATG>A‐G) (αIniCdα), two‐gene deletion (SEA), and single‐gene 3.7‐kb deletion (‐α3.7). For β‐thalassaemia, there were Cd26 (G>A) Hb E (βE), Cd19 (A>G) Haemoglobin Malay (Hb Malay) (βCd19), and IVS 1–5 (G>C) (βIVS 1–5).  相似文献   
98.

Introduction

Skin aging may occur as a result of increased free radicals in the body. Vitamin E, the major chain-breaking antioxidant, prevents propagation of oxidative stress, especially in biological membranes. In this study, the molecular mechanism of tocotrienol-rich fraction (TRF) in preventing oxidative stress-induced skin aging was evaluated by determining the rate of total collagen synthesis and its gene expression in human skin fibroblasts.

Material and methods

Primary culture of human skin fibroblasts was derived from circumcision foreskin of 9 to 12 year-old boys. Fibroblast cells were divided into 5 different treatment groups: untreated control, hydrogen peroxide (H2O2)-induced oxidative stress (20 µM H2O2 exposure for 2 weeks), TRF treatment, and pre- and post-treatment of TRF to H2O2-induced oxidative stress.

Results

Our results showed that H2O2-induced oxidative stress decreased the rate of total collagen synthesis and down-regulated COL I and COL III in skin fibroblasts. Pre-treatment of TRF protected against H2O2-induced oxidative stress as shown by increase in total collagen synthesis and up-regulation of COL I and COL III (p<0.05) genes. However, similar protective effects against H2O2-induced oxidative stress were not observed in the post-treated fibroblasts.

Conclusions

Tocotrienol-rich fraction protects against H2O2-induced oxidative stress in human skin fibroblast culture by modulating the expression of COL I and COL III genes with concomitant increase in the rate of total collagen synthesis. These findings may indicate TRF protection against oxidative stress-induced skin aging.  相似文献   
99.
Background/Aims17β-hydroxysteroid dehydrogenase 13 (HSD17B13) variants were recently reported to have significantly lower odds of non-alcoholic fatty liver disease (NAFLD). This is a two-part study that aimed to evaluate the association of HSD17B13 variants with NAFLD and its histological severity, and to identify the association of the variants with clinical outcomes in a cohort of biopsy-proven NAFLD patients.MethodsConsecutive biopsy-proven NAFLD patients and controls without fatty liver were recruited for this study between 2009 and 2014. Genotyping for HSD17B13 variants was performed using rhAmp assays. A total of 165 patients with NAFLD were monitored up until August 2019. Clinical outcomes were recorded.ResultsHSD17B13 rs72613567 TA allele and rs6834314 G allele were associated with lower odds of non-alcoholic steatohepatitis (NASH) in the overall cohort and among ethnic Chinese, but not among ethnic Malays or Indians (P<0.05). During a mean follow-up of 89 months, 32 patients (19.4%) experienced at least one clinical outcome (cardiovascular events, n=22; liver-related complications, n=6; extra-hepatic malignancy, n=5; and mortality, n=6). The rs72613567 homozygous TA allele and the rs6834314 homozygous G allele were independently associated with a lower incidence of liver-related complications (hazard ratio [HR], 0.004; 95% confidence interval [CI], 0.00–0.64; P=0.033 and HR, 0.01; 95% CI, 0.00–0.97; P=0.048, respectively) and were associated with lower grade of hepatocyte ballooning among the ethnic Chinese.ConclusionHSD17B13 rs72613567 and rs6834314 variants were inversely associated with NAFLD and NASH, and were associated with lower incidence of adverse liver outcomes in a cohort of multi-ethnic Asian patients with NAFLD.  相似文献   
100.

Objective:

To optimize the delay time before the initiation of arterial phase scan in the detection of focal liver lesions in contrast enhanced 5 phase liver CT using the bolus tracking technique.

Patients and Methods:

Delay - the interval between threshold enhancement of 100 hounsfield unit (HU) in the abdominal aorta and commencement of the first arterial phase scan. Using a 16 slice CT scanner, a plain CT of the liver was done followed by an intravenous bolus of 120 ml nonionic iodinated contrast media (370 mg I/ml) at the rate of 4 mL/s. The second phase scan started immediately after the first phase scan. The portal venous and delay phases were obtained at a fixed delay of 60 s and 90 s from the beginning of contrast injection. Contrast enhancement index (CEI) and subjective visual conspicuity scores for each lesion were compared among the three groups.

Results:

84 lesions (11 hepatocellular carcinomas, 17 hemangiomas, 39 other hypervascular lesions and 45 cysts) were evaluated. CEI for hepatocellular carcinomas appears to be higher during the first arterial phase in the 6 seconds delay group. No significant difference in CEI and mean conspicuity scores among the three groups for hemangioma, other hypervascular lesions and cysts.

Conclusion:

The conspicuity of hepatocellular carcinomas appeared better during the early arterial phase using a bolus tracking technique with a scan delay of 6 seconds from the 100 HU threshold in the abdominal aorta.  相似文献   
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