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71.
Microbes have long been used for the synthesis of a variety of nanoparticles. Hepatocellular carcinoma (HCC) is the primary liver cancer and it is the second leading cause of cancer‐related mortality worldwide. In this study, we have synthesized Enterococcus mediated gold nanoparticles (AuNPs) and investigated their cytotoxic potential against human hepatocellular cancer cell line (HepG2). AuNPs were synthesized using Enterococcus sp. RMAA. HepG2 cells were treated with different concentrations of AuNPs for 24 hours and cytotoxicity was analyzed by MTT ((4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide) assay. AuNPs induced reactive oxygen species expression was analyzed by 2′,7′‐dichlorodihydrofluorescein diacetate staining. Morphological changes related to apoptosis was analyzed by annexin V/propidium iodide staining. Protein expression of proliferating cell nuclear antigen (PCNA) was done by western blotting analysis. Bacterial‐mediated AuNPs caused significant cytotoxicity in HepG2 cells. AuNPs treatment also caused the significant expression of ROS and morphological damage related to apoptosis. AuNPs treatments were responsible for the dislocation of cytochrome c from mitochondria to cytosol. The protein expression of PCNA was significantly decreased upon AuNPs treatment. These findings suggest that Enterococcus‐mediated AuNPs can inhibit the proliferation of HepG2 cells via intracellular ROS mediated apoptosis, decreased PCNA expressions, and it may have the potential to treat HCC.  相似文献   
72.
A study was done on patients admitted to Penang Hospital with malignant disease in 1995. A total of 1333 patients (638 male, 695 female) with 1335 malignancies were studied. The majority (77.3%) were aged 41-80 years. The commonest cancers in males were cancers of lung, nasopharynx, colon and rectum, leukemia and larynx whereas the commonest malignancies in females were of the breast, cervix, colon and rectum, leukemia and ovarian/lung carcinoma. The average number of admissions was 2.2 and the average length of stay was 12.7 days. Cancer admissions account for a significant proportion of the inpatient workload of Penang Hospital.  相似文献   
73.
Introduction: Undercorrections have been reported after a number of surgical procedures for Brown’s syndrome. The reason for late undercorrections is not clear but may be related to the heterogeneous etiology of Brown’s syndrome.

Purpose: We report a patient with late undercorrection after superior oblique tendon recession for Brown’s syndrome that was partially relieved by a silicone spacer placed nasally.

Results: We noted on surgical exploration that the superior oblique tendon had attached to the sclera under the nasal border of the superior rectus. Further weakening of the tendon was achieved by a No. 240 band expander that resulted in improvement of adduction in elevation.

Conclusion: Undercorrections following surgery for Brown’s syndrome can be relieved by further weakening the superior oblique muscle. However, as late undercorrections have been reported, the optimal timing of surgery is not certain.  相似文献   

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75.
Acute exposure of rats to acrolein (1 or 2 ppm) resulted in reduced levels of glutathione, ascorbic acid and alpha-tocopherol. The activities of catalase and glutathione peroxidase were reduced whereas an increase in the activities of superoxide dismutase was observed. This led to enhanced lipid peroxidation, which produced extensive lung damage as indicated by the elevated levels of the biochemical markers--angiotensin converting enzyme, lactate dehydrogenase, protein and lactate in the bronchoalveolar lavage.  相似文献   
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78.

Objectives:

This study was aimed to assess the cardioprotective role of low molecular weight glycosaminoglycans (LMW-GAG) in isoproterenol (ISO)-induced myocardial infarction (MI) in male Wistar rats. Effect of LMW-GAG on biomolecules, lactate dehydrogenase (LDH)-isoenzyme, and electrocardiographic (ECG)-patterns was studied as evidence of cardioprotection.

Materials and Methods:

Male Wistar rats (140 ± 10 g) were divided into four groups; untreated control (group I), LMW-GAG treated (300 μg/day s. c. for 2 weeks—group II), ISO (85 mg s.c. injected on 13th and 14th days—group III), and LMW-GAG plus ISO (300 μg/day s. c. for 12 days followed by 85 mg/kg ISO on the end of 13th and 14th days—group IV). At the end of the experimental period, all animals were terminated.

Results:

Rats treated with LMW-GAG (300 μg/kg) for 12 days showed significant increasing levels of triglyceride (TG) (both serum and heart tissue), low density lipoprotein (LDL), very low density lipoprotein (VLDL), total cholesterol, uric acid, creatinine, and glucose. However, it significantly decreased the levels of high density lipoprotein (HDL) (serum), plasma total protein, and albumin/globulin (A/G) ratio. ISO also adversely affected the LDH-isoenzymes and caused marked elevation in ST segment. Pretreatment with LMW-GAG (300 μg/kg) daily for a period of 2 weeks prevented the ISO-treated changes.

Conclusions:

The results indicate that LMW-GAG exhibits a cardioprotective effect in ISO-induced MI in rats, by maintaining the biomolecules and LDH-isoenzymes.KEY WORDS: A. pleuronectus, ECG, LDH-isoenzyme, LMW-GAG, myocardial infarction  相似文献   
79.
Shigella dysenteriae continues to be a major health problem, which leads to death, due to diarrhoea and dysentery, predominantly in children below the age of 5. Bacterial invasion of the colonic epithelium leads to severe inflammation together with bacterial dissemination generates abscesses and ulcerations. Periplasmic copper, zinc super oxide dismutase of Shigella protects it from exogenous superoxide produced by host, during its invasion. Hence, in present study an attempt was made to study the effect of aqueous extract of Aegle marmelos on host and pathogen defence. Histology analysis of rat ileal loop showed the loss of virulence in aqueous extract of A. marmelos pre-treated Shigella and their intracellular survival was also decreased, where active component present in aqueous extract of A. marmelos was identified as imperatorin confirmed by UV absorption spectrum and HPLC. Increase in peripheral blood mononuclear cell viability and decreased in intracellular bacterial count along with transmission electron microscope analysis of imperatorin treated S. dysenteriae succumb to host oxidative stress. Loss of virulence is associated with attenuation of copper, zinc super oxide dismutase activity in Shigella, which was confirmed by using activity staining of bacterial cell lysate. Further, by performing docking analysis it has been proved that imperatorin present in aqueous extract of A. marmelos inhibited copper, zinc super oxide dismutase. From the above study, we concluded that Shigella succumb to oxidative stress (host defence) due to inhibition of copper, zinc super oxide dismutase (pathogen's defence) by imperatorin, an active compound aqueous extract of A. marmelos.  相似文献   
80.
Background: Survivin has been implicated in cancer progression and is known to be over-expressed in a variety of human malignancies. Positive regulation of survivin expression provides a connecting link between cell cycle and tumorigenesis or perhaps tumour maintenance. Methods: An experiment was designed to analyse survivin expression in cell lines (MCF 7, Zr751, A549, HepG2) using SDS-PAGE, Western blots, RT-PCR, AGE and heamatoxylin-eosin staining were done. Results: SDS-PAGE revealed the presence of 16.5 kDa protein. Subsequent western Blot and cytological analysis showed down-regulation of survivin expression in cancer cells. Conclusion: Therefore, the study allows the conclusion that survivin is essential for proper chromosome segregation and cytokinesis. It seems reasonable to suspect that abnormal expression or function of survivin might contribute to multinucleated and apoptotic conditions.  相似文献   
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