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101.
102.
Hepatocellular carcinoma (HCC) is highly resistant to anticancer therapy and novel therapeutic strategies are needed. Chronotherapy may become a promising approach because it may improve the efficacy of antimitotic radiation and chemotherapy by considering timing of treatment. To date little is known about time‐of‐day dependent changes of proliferation and DNA damage in HCC. Using transgenic c‐myc/transforming growth factor (TGFα) mice as HCC animal model, we immunohistochemically demonstrated Ki67 as marker for proliferation and γ‐H2AX as marker for DNA damage in HCC and surrounding healthy liver (HL). Core clock genes (Per1, Per2, Cry1, Cry2, Bmal 1, Rev‐erbα and Clock) were examined by qPCR. Data were obtained from samples collected ex vivo at four different time points and from organotypic slice cultures (OSC). Significant differences were found between HCC and HL. In HCC, the number of Ki67 immunoreactive cells showed two peaks (ex vivo: ZT06 middle of day and ZT18 middle of night; OSC: CT04 and CT16). In ex vivo samples, the number of γ‐H2AX positive cells in HCC peaked at ZT18 (middle of the night), while in OSC their number remained high during subjective day and night. In both HCC and HL, clock gene expression showed a time‐of‐day dependent expression ex vivo but no changes in OSC. The expression of Per2 and Cry1 was significantly lower in HCC than in HL. Our data support the concept of chronotherapy of HCC. OSC may become useful to test novel cancer therapies.  相似文献   
103.

Objective

To determine the clinical utility of serum neutrophil gelatinase-associated lipocalin (NGAL) as an early marker of acute kidney injury in asphyxiated neonates with hypoxic ischemic encephalopathy (HIE).

Design

Cohort study.

Settings

National Intensive Care Unit of Maternity Hospital, Ain Shams University, Cairo, Egypt.

Patients

The study included 30 term asphyxiated neonates (8 with mild, 13 with moderate and 9 with severe HIE) and 20 control neonates.

Intervention

Serum NGAL level was measured within 6 hours after birth using an enzyme linked immunosorbent assay.

Main outcome measures

Patients were subsequently discriminated into AKI (n=12) and no-AKI (n=18) groups.

Results

The median (Interquartile range) serum NGAL concentration was 95.0 (70.75–180.00) ng/mL in asphyxiated neonates, and 39.75 (6.0–48.0) ng/mL in control neonates; (P<0.001). Serum NGAL correlated with HIE severity: mean (SD) was 65.50 (3.77) ng/mL in infants with mild HIE, 115.07 (45.83) ng/mL in infants with moderate HIE and 229.66 (79.50) ng/mL in infants with severe HIE; (P<0.01). The median (Interquartiles) serum NGAL level was 182.50 (166.25–301.75) ng/mL in patients with AKI, 74.00 (66.00–78.75) ng/mL in those without AKI; (P<0.001). A cutoff value 157 ng/mL for serum NGAL could detect AKI in asphyxiated neonates with a sensitivity of 83.3% and a specificity of 94.4%.

Conclusion

Elevated serum NGAL measured within 6 hours after birth reliably indicates acute kidney injury in asphyxiated neonates.  相似文献   
104.
Thimerosal is a widely used preservative in health care products, especially in vaccines. Due to possible adverse health effects, investigations on its metabolism and toxicity are urgently needed. An in vivo study on chronic toxicity of thimerosal in rats was inconclusive and reports on genotoxic effects in various in vitro systems were contradictory. Therefore, we reinvestigated thimerosal in the cytochalasin B block micronucleus test. Glutathione S-transferases were proposed to be involved in the detoxification of thimerosal or its decomposition products. Since the outcome of genotoxicity studies can be dependent on the metabolic competence of the cells used, we were additionally interested whether polymorphisms of glutathione S-transferases (GSTM1, GSTT1, or GSTP1) may influence the results of the micronucleus test with primary human lymphocytes. Blood samples of six healthy donors of different glutathione S-transferase genotypes were included in the study. At least two independent experiments were performed for each blood donor. Significant induction of micronuclei was seen at concentrations between 0.05-0.5 micro g/ml in 14 out of 16 experiments. Thus, genotoxic effects were seen even at concentrations which can occur at the injection site. Toxicity and toxicity-related elevation of micronuclei was seen at and above 0.6 micro g/ml thimerosal. Marked individual and intraindividual variations in the in vitro response to thimerosal among the different blood donors occurred. However, there was no association observed with any of the glutathione S-transferase polymorphism investigated. In conclusion, thimerosal is genotoxic in the cytochalasin B block micronucleus test with human lymphocytes. These data raise some concern on the widespread use of thimerosal.  相似文献   
105.
We present an interesting and relatively uncommon case of vestibular pneumolabyrinth in a young child post-trauma. His initial clinical exam and imaging studies of the head and cervical spine were negative. He subsequently developed nystagmus and a dedicated temporal bone study demonstrated a subtle fracture and vestibular pneumolabyrinth. Temporal bone fractures can be difficult to appreciate, and therefore, associated findings of fluid in the middle ear, stapes dislocation, or vestibular pneumolabyrinth must be carefully evaluated. Temporal bone computed tomography is a high resolution study, utilizing dynamic focal spot mode which leads to increased sampling and resolution, thereby reducing aliasing artifacts but a longer scan time and increased radiation dose. CT head and cervical spine normally obtained without using this technique leads to aliasing artifacts where even the normal endolymph in the inner ear structures appear hypodense mimicking pneumolabyrinth, thereby obscuring true pneumolabyrinth. It is important to be aware of this finding and technique-related artifact, if a temporal bone injury is suspected, to ensure an earlier diagnosis and optimum management.  相似文献   
106.
107.

Background

Oxidative stress has a key role in the pathogenesis of type II diabetes mellitus (T2DM) and its vascular complications. Antioxidant therapy has been suggested as a potential approach to blunt T2DM development and progression. The aim of this study was to assess the effects of supplementation with curcuminoids, which are natural polyphenolics from turmeric, on oxidative indices in diabetic individuals.

Methods

In this randomized double-blind placebo-controlled trial, 118 subjects with T2DM were randomized to curcuminoids (1000 mg/day co-administered with piperine 10 mg/day) or matching placebo for a period of 8 weeks. Serum total antioxidant capacity, superoxide dismutase (SOD) activities and malondialdehyde (MDA) concentrations were measured at baseline and after the supplementation period.

Results

Curcuminoids supplementation caused a significant elevation in serum total antioxidant capacity (TAC) (p < 0.001) and SOD activities (p < 0.001), while serum MDA levels were significantly reduced compared with the placebo group (p < 0.001). These results remained statistically significant after adjustment for potential confounders (baseline differences in body mass index and fasting serum insulin).

Conclusion

The present results support an antioxidant effect of curcuminoids supplementation in patients with T2DM, and call for future studies to assess the impact of these antioxidant effects on the occurrence of diabetic complications and cardiovascular endpoints.
  相似文献   
108.
1. The aim of the present study was to determine whether the addition of a subeffective dose of rimonabant (1 mg/kg) to orlistat would be beneficial in the treatment of diet-induced obesity in rats compared with orlistat monotherapy. 2. Male rats were divided into five groups: (i) rats fed a low-fat diet for 4 months; (ii) rats fed a high-fat diet (HFD) for 4 months and treated daily with vehicle (0.2% Tween-80 solution); (iii) orlistat (10 mg/kg per day)-treated HFD-fed rats; (iv) rimonabant (1 mg/kg per day)-treated HFD-fed rats; and (v) HFD-fed rats treated with a combination of orlistat plus rimonabant. Fasting blood glucose, serum insulin, leptin and adiponectin levels were measured. Liver and adiposity indices were calculated and liver and adipose tissues were processed for histological examination. 3. Over the 4 months of the study, vehicle-treated HFD-fed rats exhibited increased cumulative food intake, bodyweight and liver and adiposity indices. Moreover, vehicle-treated HFD-fed rats exhibited a deterioration in liver function and an abnormal lipid profile. Insulin resistance and serum leptin were increased in this group, whereas serum adiponectin levels were decreased. Orlistat monotherapy or combination therapy with orlistat plus rimonabant improved all these parameters. 4. The addition of the low subeffective dose of rimonabant to orlistat therapy ameliorated HFD-induced obesity to a much greater extent than orlistat monotherapy. This combination showed better weight control and metabolic profile compared with orlistat alone. Therefore, the results of the present study encourage reassessment of the use of a low dose of rimonabant to potentiate the effect of orlistat in the clinical management of obesity if proper clinical safety data are available.  相似文献   
109.
Hookah (water pipe) smoking, an old method of tobacco smoking, is regaining widespread popularity all over the world. Although the research in this field is still deficient, it has been proven for its harmful effect on human's health by increasing the risk of cardiovascular disease, infection and lung, oral and bladder cancer (Al-Numair et al., J Food Agric Environ, 5: 17, 2007; Bou Fakhreddine et al., Respir Med, 108: 1241–1253, 2014; Chaouachi, J Negat Results Biomed, 5: 17, 2006). However, no research was found to address its effect on human fertility or reproductive outcome. In this cross-sectional study, we aim to explore the effect of smoking hookah on human semen parameters among men attending In Vitro Fertilization LABs for seminal fluid analysis testing. 104 patients aged between 25 and 45, who are noncigarette smokers and have no chronic medical illness, were enrolled in the study: 50 hookah nonsmokers and 54 hookah smokers. Their semen parameters were compared. Semen volume, normal morphology and progressive motility were slightly lower in the hookah smoker (3.21 ml; 10.2%; 29.56%) versus (3.45 ml; 11.5%; 33.20%), respectively, in nonhookah smokers; however, the difference was not statistically significant. The effect of hookah smoking on semen observed in our study was not statistically significant. Further studies are needed to explore more and confirm any unfavourable effect.  相似文献   
110.
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