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101.
Context: Chronic oral intake of high doses of monosodium glutamate (MSG) could be harmful to tissues and organs. Oxidative stress enhances membrane damage by lipid peroxidation and alterations of antioxidant enzymes, which affects the functional activity of organs. Antioxidant vitamins have the capacity to regulate the oxidative stress related functional and pathological processes. Objective: In this study, the protective role of α-tocopherol against MSG-induced nephrotoxicity was analyzed. Materials and methods: MSG (4?g/kg) was given orally to female wistar rats for a period of 180 days. Renal function parameters (urea, uric acid, and creatinine), lipid peroxidation markers (malondialdehyde and conjugated dienes), antioxidant system (superoxide dismutase, catalase, glutathione peroxidase, glutathione transferase, and reduced glutathione), and histopathology were investigated. All tests were done in rats treated with MSG and at two different doses of α-tocopherol (100 and 200?mg/kg). Results: Oral exposure of MSG significantly increased renal function markers, lipid peroxidation byproducts, and altered antioxidant system. Moreover, the kidney showed congested glomeruli, tubular swelling, capillary congestion and microhemorrhages in stromal areas of the tubules. Co-administration of MSG and α-tocopherol (200?mg/kg) significantly reduced the oxidative damage compared with MSG-treated group and also restored the normal renal function. Discussion: The results indicated that oxidative stress was involved in MSG-induced functional and pathological changes in the kidney. α-tocopherol modulates the functional disorder and maintains the normal architecture of renal tissue by reducing oxidative stress. Conclusion: The α-tocopherol may be a potent protective agent in combating MSG-induced renal toxicity.  相似文献   
102.
Optimal cognitive and emotional function is vital to independence, productivity, and quality of life. Cognitive impairment without dementia may be seen in 16% to 33% of adults older than 65 years, and is associated with significant emotional distress. Cognitive and emotional well-being are inextricably linked. This article qualifies revitalizing the aged brain, discusses neuroplasticity, and suggests practical neuroplasticity-based strategies to improve the cognitive and emotional well-being of older adults.  相似文献   
103.
Frogs in the genus Indirana are endemic to Western Ghats biodiversity hotspot. The species are poorly studied and in many cases threatened or endangered. Here we describe primers and polymerase chain reactions for 62 microsatellite loci for Indirana beddomii, one of the commonest frogs in the genus. Fifty-six of the primers were polymorphic on sample of 23 individuals from a single sampling site (Ponmudi, Kerala) with an average 9.11 alleles per locus (range = 2–20). The average observed and expected heterozygosities were 0.64 and 0.71, respectively. The loci should be useful in conservation genetic studies of Indirana frogs.  相似文献   
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As the more obvious clinical manifestations of the disease are very uncommon in children, lymphatic filariasis has been considered to be primarily a disease of adults. In many recent reports, however, there is evidence indicating not only that filarial infection is commonly acquired in childhood but also that many infected children already have irreversible damage to their lymphatics. The preliminary results of a cross-sectional study on the patterns of Brugia-attributable pathology in 7934 children (aged 3-15 years) who live in an area of India with endemic B. malayi infection confirm these trends. The children were screened for microfilaraemia, evidence of filarial disease, and the presence of antifilarial IgG(4) antibodies. One hundred children who were microfilaraemic but asymptomatic (32), with filarial disease or an history of such disease or microfilaraemia (29) or amicrofilaraemic and asymptomatic but seropositive for antifilarial IgG(4) (39) were investigated further. They were given detailed clinical examinations, their levels of microfilaraemia were evaluated (by counting microfilariae filtered out of blood samples), their lymphatics were explored by Doppler sonography, and their limbs were checked by lymphoscintigraphy. The 'filarial dance sign', which indicates the presence of live adult worms, was detected by sonography in 14 children (apparently the first time this sign has been observed in brugian filariasis). Lymphoscintigraphy revealed dilated lymphatic channels in the limbs of 80 of the children. At the end of the study, each of the 100 hospitalized children was treated with a single combined dose of diethylcarbamazine and albendazole; the aim is to follow-up the treated children every 6 months for 3 years. Even these preliminary results have important implications for filariasis-control programmes and emphasise the need for disability-alleviation efforts among children as well as adults.  相似文献   
107.

Background

The limited space and high magnification involved in minimally invasive surgery (MIS) can cause surgeons to lose sight of an instrument while performing tasks such as suturing and knot-tying. A current strategy employed to locate the instrument is zooming out and in with the endoscope, which can be a time-intensive and iterative task. This study investigates the use of a supplemental wide field of view (FOV) via a second endoscope for locating an instrument outside the FOV in a MIS setting.

Methods

Ten surgically naïve subjects performed a simple aimed movement task with either hand (dominant or nondominant) under two display conditions: (1) conventional single monitor with zoom, and (2) supplemental wide FOV monitor with no zoom. The task emulated the need to locate an instrument outside the surgeon’s FOV and return it to a home position.

Results

The supplemental wide FOV produced significantly faster times [F(3,716) = 173.2, p < 0.001)] compared to a single monitor. The task was accomplished most quickly with the dual monitor with the dominant hand, followed by dual monitor with nondominant hand followed by a single monitor with either hand. There were also significantly fewer errors (t = 3.734, df = 9, p = 0.005) with the supplemental wide FOV. None of the subjects were slower with the dual monitor, and all but one had fewer errors. The variance for both task times and errors were also significantly smaller (p < 0.001 and p = 0.008, respectively) with the supplemental wide FOV indicating that subjects performed with increased reliability.

Conclusion

The supplemental wide FOV gave the subjects the ability to see their instrument at all times providing a more efficient display than zooming out and in. This enabled faster times and fewer errors while allowing the user to perform the task with more consistency.
  相似文献   
108.
BACKGROUND: Adoptive transfer of antigen-primed T-cell-activated macrophages into NOD-SCID mice within 14 days of foetal porcine pancreatic fragment (FPP) or foetal porcine skin (FPS) transplantation had been shown to cause xenograft rejection. In the present study, it was proposed that signaling between the graft and macrophages promoted specific graft recognition and destruction in this setting. METHODS: Exogenous macrophages isolated from rejecting FPP xenografts were transferred to NOD-SCID FPP recipients and tracked by Ly5.1 surface antigen or via CSFE staining. Monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-1alpha (MIP-1alpha), macrophage inflammatory protein-1beta (MIP-1beta), regulated upon activation, normal T-cell expressed and secreted (RANTES), chemokine (C-C motif) receptor 2 (CCR2), chemokine (C-C motif) receptor 5 (CCR5), toll-like receptors (TLRs) (1-9) and gene expression in transplanted FPP xenografts was evaluated by real-time polymerase chain reaction. Gene expression of CCR2, CCR5 and TLRs was also analyzed in pooled samples of activated and non-activated macrophages. RESULTS: Exogenous macrophages were shown to track to and reject recently transplanted but not established FPP xenografts. Gene expression for MCP-1, RANTES, MIP-1alpha and MIP-1beta was at least 3-fold greater in recently transplanted compared with established xenografts (P < 0.05), and CCR2 and CCR5 gene expression was 10-fold greater in activated compared non-activated macrophages, suggesting that graft-mediated pro-inflammatory signals were important for macrophage recruitment. Specific graft recognition by macrophages may involve TLR signaling as macrophages exposed to porcine islets had higher levels of TLR gene expression compared with those exposed to allografts regardless of the level of activation. CONCLUSION: Xenografts provide additional activation signals to macrophages that are not seen following allotransplantation. This study identifies chemokines and TLR as important signals in macrophage-mediated recognition and rejection of islet xenografts.  相似文献   
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The present study reports the synthesis of the Fe2O3/Cu2O nanocomposite via a facile hydrothermal route. The products were characterized using X-ray diffractometry (XRD), Fourier-transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), high-resolution transmission electron microscopy (HR-TEM), energy dispersive spectroscopy (EDS) and Brunauer–Emmett–Teller (BET) techniques. The composition, morphology and structural features of the nanoparticles were found to be size-dependent due to the temperature response in the particular time log during hydrothermal synthesis. HR-TEM confirmed the formation of hexagonal rod-shaped bare Cu2O, rhombohedral-shaped Fe2O3 and composite assembly. Rhodamine-B (RB) and Janus green (JG) were chosen as model dyes for the degradation studies. Photocatalytic degradation of the dyes was deliberated by altering the catalyst and dye concentrations. The results showed that the Rhodamine-B (RB) and Janus green (JG) dyes were degraded within a short time span. The synthesized materials were found to be highly stable in the visible light-driven degradation of the dyes; showed antibacterial activity against E. coli, P. aeruginosa, Staph. aureus and B. subtilis; and exhibited less toxicity against the Musmusculus skin melanoma cells (B16-F10). The fusion of these advantages paves the way for further applications in energy conversion, biological applications as well as in environmental remediation.

The present study reports the synthesis of the Fe2O3/Cu2O nanocomposite via a facile hydrothermal route.  相似文献   
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