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21.
The performance ofNodularia harveyana, a N2-fixing cyanobacterium isolated from seawater, has been studied outdoors in two different culture systems: open pond (OP) and tubular photobioreactor (TPR). The productivity in both devices was influenced by areal density. The maximum yield obtained was 12.0 g (d.wt) m–2 day–1 in OP and 14.0 g (d.wt) m–2 day–1 in TPR in August, corresponding to the highest solar radiation received. In a month-long experiment with the cyanobacterium cultivated in TPR at high circulation speed, a net increase in productivity was obtained over that at low circulation speed. The influence of temperature on the productivity of the cultures grown in open ponds and tubular photobioreactors has been investigated. The higher productivity obtained in TPR compared to OP was attributed to its better controlled temperature conditions. In outdoor culture the maximum nitrogenase activity did not coincide with the maximum light intensity, but occurred in early afternoon. The amount of carbohydrate accumulated during the day probably influenced the rate of dark nitrogenase activity and its duration in the night.  相似文献   
22.
Tumor lysis syndrome (TLS) is characterized by hyperuricaemia, hyperphosphatemia, hyperkalaemia, as well as hypocalcaemia due to the breakdown of tumor cells undergoing cancer therapy (chemo/radio). Therefore it is of interest to evaluate oxidative stress using selective biological markers [Malondialdehyde (MDA), Superoxide Dismutase (SOD), Glutathione (GSH) and Catalase (CAT)] in TLS. We report the marked differences (statistically significant with control) observed among a selected set of biomarkers of oxidative stress (MDA = 8.66±1.37; SOD = 0.15±0.11; GSH = 2.25±.77; CAT = 0.76±.57) in TLS patients in addition to other conventional biomarkers. Moreover, correlation was investigated among the parameters of oxidative stress and other circulating biomarkers of TLS. Data suggest the use of SOD, MDA, and GSH as potential diagnostic biomarker for TLS with other biomarkers.  相似文献   
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Electrospinning is a versatile process used to prepare micro- and nano- sized fibers from various polymers dissolved in volatile solvents. In this report, cellulose and cellulose-heparin composite fibers are prepared from nonvolatile room temperature ionic liquid (RTIL) solvents by electrospinning. RTILs are extracted from the biopolymer fiber after the fiber formation using a cosolvent. Micron to nanometer sized, branched fibers were obtained from 10% (w/w) concentration of polysaccharide biopolymer in RTIL solution with an applied voltage of 15-20 kV. Cellulose-heparin composite fibers showed anticoagulant activity, demonstrating that the bioactivity of heparin remained unaffected even on exposure to a high voltage involved in electrospinning.  相似文献   
25.
Shetty SR  Mishra C  Shetty P  Kaur A  Babu S 《Gerodontology》2012,29(2):e1133-e1135
Schwannoma also known as neurilemmoma is a benign tumour derived from schwann cells and is relatively rare in occurrence. Only 1% of the schwannomas in the head and neck region occur at intra-oral sites. Schwannomas usually occur during the third or fourth decades of life and the tongue is the most common intra-oral site. A case of intra-oral schwannoma in a 70-year-old female in the region of hard palate is described which is extremely rare.  相似文献   
26.
This study has been undertaken to explore the therapeutic effects of deguelin and specific siRNAs in HeLa cells. The data provided clearly show the silencing of ERK 1/2 with siRNAs and inhibition of ERK1/2 with deguelin treatment in HeLa cells. Additionally, we are providing information that deguelin binds directly to anti-apoptotic Bcl-2, Bcl-xl and Mcl-1 in the hydrophobic grooves, thereby releasing BAD and BAX from dimerization with these proteins. This results in increased apoptotic activity through the intrinsic pathway involved in rupture of mitochondrial membrane and release of cytochrome C. Evidence for inhibition of ERK1/2 by deguelin and escape of BAD phosphorylation at serine 112 through ERK/RSK pathway has been further fortified by obtaining similar results by silencing ERK 1/2 each with specific siRNAs. Increase in BAD after treatment with deguelin or siRNAs has been interpreted to mean that deguelin acts through several alternative pathways and therefore can be used as effective therapeutic agent.  相似文献   
27.
Atherosclerosis is an inflammatory disease mediated by interferon (IFN-γ) in concert with cell adhesion molecules and chemokines. Thymoquinone (TQ), a flavonoid derived from Nigella sativa, is reported to have anti-inflammatory, antioxidant, and cardiovascular protective properties. We evaluated the effects of TQ on the key pathogenic stages of atherosclerosis, including cell viability, inflammatory gene expression, cell migration, and cholesterol efflux, on human THP-1 macrophages in-vitro. Moreover, in-silico analysis was performed to predict the molecular targets and signaling mechanisms. We demonstrated that TQ treatment had no effect on cell viability and decreased the expression of monocyte chemoattractant protein (MCP-1) and intercellular adhesion molecule (ICAM-1) in response to IFN-γ. In addition, we have also demonstrated that the THP-1 cell migration was inhibited by TQ in the absence or presence of MCP-1. Thymoquinone had no effect on cholesterol efflux from monocytes. In-silico analysis also identified several putative targets for TQ that are associated with inflammatory diseases and associated signaling pathways. Collectively, these results suggest that TQ has anti-inflammatory effects and may be a potential nutraceutical candidate for the prevention and treatment of atherosclerosis.  相似文献   
28.
Deivasigamani C  Das N 《Biodegradation》2011,22(6):1169-1180
Basic Violet 3 (BV) belongs to the most important group of synthetic colorants and is used extensively in textile industries. It is considered as xenobiotic compound which is recalcitrant to biodegradation. As Candida krusei could not use BV as sole carbon source, experiments were conducted to study the effect of cosubstrates on decolorization of BV in semi synthetic medium using glucose, sucrose, lactose, maltose, yeast extract, peptone, urea and ammonium sulphate. Maximum decolorization (74%) was observed in media supplemented with sucrose. Use of sugarcane bagasse extract as sole nutrient source showed 100% decolorization of BV within 24 h under optimized condition. UV–visible, FTIR spectral analysis and HPLC analysis confirmed the biodegradation of BV. Six degradation products were isolated and identified. We propose the biodegradation pathway for BV which occurs via stepwise reduction and demethylation process to yield mono-, di-, tri-, tetra-, penta- and hexa-demethylated BV species which was degraded completely. The study of the enzymes responsible for decolorization showed the activities of lignin peroxidase, lacasse, tyrosinase, NADH-DCIP reductase, MG reductase and azoreductase in cells before and after decolorization. A significant increase in activities of NADH-DCIP reductase and laccase was observed in the cells after decolorization. The yeast C. krusei could show the ability to decolorize the textile dye BV using inexpensive source like sugarcane bagasse extract for decolorization.  相似文献   
29.
The human immunodeficiency virus type-1 (HIV-1) gp160 (gp120-gp41 complex) trimer envelope (ENV) protein is a potential vaccine candidate for HIV/AIDS. HIV-1 vaccine development has been problematic and charge polarity as well as sequence variation across clades may relate to the difficulties. Further obstacles are caused by sequence variation between blood and brain-derived sequences, since the brain is a separate compartment for HIV-1 infection. We utilize a threedimensional residue measure of solvent exposure, accessible surface area (ASA), which shows that major segments of gp120 and gp41 known structures are solvent exposed across clades. We demonstrate a large percent sequence polarity for solvent exposed residues in gp120 and gp41. The range of sequence polarity varies across clades, blood, and brain from different geographical locations. Regression analysis shows that blood and brain gp120 and gp41 percent sequence polarity range correlate with mean Shannon entropy. These results point to the use of protein modifications to enhance HIV-1 ENV vaccines across multiple clades, blood, and brain. It should be noted that we do not address the issue of protein glycosylation here; however, this is an important issue for vaccine design and development. ABBREVIATIONS: HIV-1 - human immunodeficiency virus type 1, AIDS - acquired immunodeficiency syndrome, ENV - envelope, gp160 - 160,000d glycoprotein, gp120 - 120,000d glycoprotein, gp41 - 41,000d glycoprotein, LANL - Los Alamos National Laboratories, PDB - Protein Data Bank, HVTN - STEP HIV vaccine trial, AA - amino acids, MSA - multiple sequence alignment, ASA - accessible surface area, SNPs- single nucleotide polymorphisms, HAART - Highly Active Antiretroviral Therapy, CCR5 - C-C chemokine receptor type 5, CNS - central nervous system, HIVE - HIV encephalitis, P - polarity, NP - non-polarity, CTL - cytotoxic T lymphocyte, NIAID - National Institute of Allergy and Infectious Diseases.  相似文献   
30.

Background

Adiponectin and leptin, two of the key cytokines secreted by adipocytes, have been shown to be associated with cardiovascular disease. However, the association of these adipocytokines with chronic kidney disease (CKD) is not clear. We examined the association of serum adiponectin, leptin levels and leptin to adiponectin ratio (LAR) with CKD in a population-based sample of Asian adults.

Methods

We conducted a case-control study (450 CKD cases and 920 controls matched for age, sex and ethnicity) involving Chinese and Indian adults aged 40–80 years who participated in the Singapore Epidemiology of Eye Diseases Study (2007–2011). CKD was defined as an estimated glomerular filtration rate <60 mL/min/1.73m2 from serum creatinine. Serum adiponectin and leptin levels were measured using commercially available ELISA. Odds ratio of CKD associated with elevated adiponectin and leptin levels were estimated using logistic regression models adjusted for age, gender, ethnicity, education, smoking, body mass index, diabetes, blood pressure, total and HDL cholesterol.

Results

CKD cases had higher levels of leptin (mean [SD] 9.7 [11.5] vs.16.9 [20.2] ng/mL, p<0.0001) and adiponectin (10.4 [7.4] vs. 9.2 [4.2], p = 0.001) compared to controls. In multi-variable models, compared to those in the lowest quartile, the OR (95% confidence interval) of CKD among those in the highest quartile were: 6.46 (3.84, 10.88), 1.94 (1.32–2.85) and 2.88 (1.78–4.64) for leptin, adiponectin and LAR. Similar associations were also observed when adiponectin and leptin were analyzed as continuous variables. This positive association of serum adiponectin, leptin and LAR with CKD was consistently present in subgroups of gender, ethnicity, diabetes, hypertension and overweight status (all P-interaction >0.1).

Conclusions

Higher levels of serum adiponectin, leptin and LAR were positively associated with CKD independent of traditional risk factors in this Asian population.  相似文献   
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