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81.
Pulmonary tuberculosis (TB) is caused by Mycobacterium tuberculosis. The protein composition of sputum may reflect the immune status of the lung. This study aimed to evaluate the protein profiles in spontaneous sputum samples from patients with active pulmonary TB. Sputum samples were collected from patients with pulmonary TB and healthy controls. Western blotting was used to analyze the amount of interleukin 10 (IL-10), interferon-gamma (IFN-γ), IL-25, IL-17, perforin-1, urease, albumin, transferrin, lactoferrin, adenosine deaminase (also known as adenosine aminohydrolase, or ADA), ADA-2, granzyme B, granulysin, and caspase-1 in sputum. Results of detection of IL-10, IFN-γ, perforin-1, urease, ADA2, and caspase-1, showed relatively high specificity in distinguishing patients with TB from healthy controls, although sensitivities varied from 13.3% to 66.1%. By defining a positive result as the detection of any two proteins in sputum samples, combined use of transferrin and urease as markers increased sensitivity to 73.2% and specificity to 71.1%. Furthermore, we observed that the concentration of transferrin was proportional to the number of acid-fast bacilli detected in sputum specimens. Detection of sputum transferrin and urease was highly associated with pulmonary TB infection. In addition, a high concentration of transferrin detected in sputum might correlate with active TB infection. This data on sputum proteins in patients with TB may aid in the development of biomarkers to assess the severity of pulmonary TB.  相似文献   
82.

Background

Concomitant supplementation of vitamins C and E during pregnancy has been reportedly associated with low birth weight, the premature rupture of membranes and fetal loss or perinatal death in women at risk for preeclampsia; however, the cause is unknown. We surmise that hypoxia-reoxygenation (HR) within the intervillous space due to abnormal placentation is the mechanism and hypothesize that concomitant administration of aforementioned vitamin antioxidants detrimentally affects trophoblast cells during HR.

Methodology/Principal Findings

Using villous explants, concomitant administration of 50 µM of vitamins C and E was observed to reduce apoptotic and autophagic changes in the trophoblast layer at normoxia (8% oxygen) but to cause more prominent apoptosis and autophagy during HR. Furthermore, increased levels of Bcl-2 and Bcl-xL in association with a decrease in the autophagy-related protein LC3-II were noted in cytotrophoblastic cells treated with vitamins C and E under standard culture conditions. In contrast, vitamin treatment decreased Bcl-2 and Bcl-xL as well as increased mitochondrial Bak and cytosolic LC3-II in cytotrophoblasts subjected to HR.

Conclusions/Significance

Our results indicate that concomitant administration of vitamins C and E has differential effects on the changes of apoptosis, autophagy and the expression of Bcl-2 family of proteins in the trophoblasts between normoxia and HR. These changes may probably lead to the impairment of placental function and suboptimal growth of the fetus.  相似文献   
83.
Prompted by an apparent relationship between ketosis and fatty acid utilization, we studied the capacities for fatty acid oxidation through β-oxidation and Krebs cycle in liver mitochondria isolated from fetal and suckling rats. Rates of state 3 oxidation, as measured by oxygen consumption, were low for both palmitylcarnitine and palmityl CoA plus carnitine at 2 days before term and at birth, but increased at least ninefold during the first 8 days of life and at least sixfold during the remaining suckling period. Despite these sharp increases, oxygen consumption in suckling rats did not exceed the value for fed adult rats. Also, the rates of state 3 oxidation of succinate were low in suckling rats. Respiratory control indices, determined with each of the three substrates, were lower in suckling rats than fed adults. By contrast, ratios of fatty acyl ester to succinate oxidation, a relative measure of the oxidation of palmitylcarnitine and palmityl CoA, were 21–66% and 27–77% higher in suckling than in fed adult rats. The increased ratios indicate that the capacity for fatty acid oxidation is higher during postnatal development than in the fetal stage or adulthood. The oxidation capacity was inversely related to glycogen content in the liver. Although hepatic carnitine concentration and carnitine palmityltransferase activity increased during suckling period, they are not rate limiting for fatty acid oxidation. Studies of the partitioning of fatty acids showed that about two-thirds of the fatty acid oxidized through β-oxidation did not enter Krebs cycle for further oxidation. These results support our working hypothesis that ketosis of suckling rats stems from rapid oxidation of fatty acids and increased partitioning of acetyl CoA into ketogenesis.  相似文献   
84.
Protein termini are determinants of protein stability. Proteins bearing degradation signals, or degrons, at their amino‐ or carboxyl‐termini are eliminated by the N‐ or C‐degron pathways, respectively. We aimed to elucidate the function of C‐degron pathways and to unveil how normal proteomes are exempt from C‐degron pathway‐mediated destruction. Our data reveal that C‐degron pathways remove mislocalized cellular proteins and cleavage products of deubiquitinating enzymes. Furthermore, the C‐degron and N‐degron pathways cooperate in protein removal. Proteome analysis revealed a shortfall in normal proteins targeted by C‐degron pathways, but not of defective proteins, suggesting proteolysis‐based immunity as a constraint for protein evolution/selection. Our work highlights the importance of protein termini for protein quality surveillance, and the relationship between the functional proteome and protein degradation pathways.  相似文献   
85.
LDL cholesterol (LDL-C) contributes to coronary heart disease. Proprotein convertase subtilisin/kexin type 9 (PCSK9) increases LDL-C by inhibiting LDL-C clearance. The therapeutic potential for PCSK9 inhibitors is highlighted by the fact that PCSK9 loss-of-function carriers exhibit 15–30% lower circulating LDL-C and a disproportionately lower risk (47–88%) of experiencing a cardiovascular event. Here, we utilized pcsk9−/− mice and an anti-PCSK9 antibody to study the role of the LDL receptor (LDLR) and ApoE in PCSK9-mediated regulation of plasma cholesterol and atherosclerotic lesion development. We found that circulating cholesterol and atherosclerotic lesions were minimally modified in pcsk9−/− mice on either an LDLR- or ApoE-deficient background. Acute administration of an anti-PCSK9 antibody did not reduce circulating cholesterol in an ApoE-deficient background, but did reduce circulating cholesterol (−45%) and TGs (−36%) in APOE*3Leiden.cholesteryl ester transfer protein (CETP) mice, which contain mouse ApoE, human mutant APOE3*Leiden, and a functional LDLR. Chronic anti-PCSK9 antibody treatment in APOE*3Leiden.CETP mice resulted in a significant reduction in atherosclerotic lesion area (−91%) and reduced lesion complexity. Taken together, these results indicate that both LDLR and ApoE are required for PCSK9 inhibitor-mediated reductions in atherosclerosis, as both are needed to increase hepatic LDLR expression.  相似文献   
86.
Complement activation is an important step for triggering of acute inflammatory reactions. Soluble human recombinant complement receptor type 1 (sCR1) blocks complement activation by both classical and alternative pathways. In addition to glycogen-induced peritonitis, three models of complement-dependent acute inflammatory injury have been used to assess the protective effects of sCR1: lung and dermal injury after intraalveolar or intradermal deposition of IgG immune complexes; acute lung injury resulting from intravascular activation of complement after the i.v. injection of cobra venom factor; and acute skin and lung injury (at 4 h) after thermal trauma involving 25 to 30% total body surface area. Vascular injury was quantified by increases in vascular permeability, hemorrhage, neutrophil infiltration, and, as indicated, tissue water content. Intravenous infusion of sCR1 reduced lung and dermal vascular injury in all models studied. In glycogen-induced peritoneal exudates sCR1-reduced neutrophil accumulation by 79%. In animals undergoing IgG immune complex-induced alveolitis, sCR1 treatment reduced vascular permeability and hemorrhage by 72 and 71%, respectively, and tissue accumulation of neutrophils was reduced by 68%. After cobra venom factor injection, sCR1 reduced increases in lung vascular permeability by 67%, hemorrhage by 73%, and lung myeloperoxidase content by 55%. Four hours after thermal injury of skin, sCR1-treated animals demonstrated significant protection against lung injury; increases in vascular permeability and hemorrhage were reduced by 45 and 46%, respectively, and myeloperoxidase content was lowered by 39%. In thermal injury of the skin, sCR1 injection reduced dermal vascular permeability by 25% at 1 h (p = NS) and 44% at 4 h. Water content in skin biopsies was also decreased. There was a dose-response relationship between the amount of sCR1 infused and the extent of protection in each of the injury models. These data demonstrate that sCR1 offers significant protection against complement-dependent tissue injury in the animal models studied and that the protective effects are related to reduced neutrophil content.  相似文献   
87.
To promote the economic feasibility of Nannochloropsis oculata, efficacy of using polyethylene glycol (PEG) to increase microalgal growth and lipid accumulation was investigated. We first examined the effects of PEG concentrations on microalgal growth using 0–5 % (w/v) PEG-6000, and followed by exploring the effects of PEG molecular weights (400, 600, 2,000, 4,000, 6,000, and 20,000) on microalgal growth, size, as well as on yields of biomass, total lipids, and eicosapentaenoic acid. In addition, the capacity of PEG to reduce the effect of oxygen inhibition on microalgal growth was also investigated to evaluate its adaptability for use in large-scale and closed setting. Our results showed that PEG-induced osmotic stress (Π) in the range of 2.465–2.472 MPa can raise microalgal growth. The PEG with higher molecular weight exhibited greater efficacy of growth promotion but less lipid content under equal concentration. In this study, 0.5 % (w/v) PEG-20000 (Π = 2.466 MPa) remarkably enhanced microalgal growth without interference of intracellular lipid productivity and cellular size, yielding >50 % (w/w) increases in biomass, total lipid, and eicosapentaenoic acid amounts after 7 days that provided the optimal condition for microalgal cultivation. These positive effects possibly resulted from the moderate enhancement of osmotic stress in the medium and stronger chaotrope-like behavior from higher molecular weight PEG. With further verification that 0.5 % (w/v) PEG-20000 enabled to reduce the effect of oxygen inhibition on microalgal growth, the PEG-20000-mediated cultivation offers a feasible means for mass culture of N. oculata in closed setting.  相似文献   
88.
Striped Marlin is a highly migratory species distributed throughout tropical and temperate waters in the North Pacific Ocean. The habitat characteristics of Striped Marlin in the western and central North Pacific Ocean were examined using generalized additive models by modelling fishery catch-rates as a function of remotely-sensed environmental covariates, including sea surface temperature (SST), chlorophyll-a concentration (CHL), mixed layer depth (MLD) and sea height anomalies (SHA). SST explained the largest proportion of the deviance, and is therefore considered the best predictor for the habitat of Striped Marlin. Spatial distributions of the relative density of Striped Marlin indicated that there is a seasonal north–south migration, and that the highest densities occur in the central North Pacific Ocean. The preferred habitat characteristics of Striped Marlin in high density areas were identified as SST between 23 and 26 °C, MLD within 30 m depth, and CHL around 0.08 mg m?3, while no preferred range was found for SHA. The results of this study could improve our understanding of Striped Marlin spatial distributions and habitat characteristics.  相似文献   
89.
The tetrasaccharides GalNAcß1-4[NeuAc2-3]Galß1-4Glc and GalNAcß1-4[NeuAc2-3]Galß1-4GlcNAc were synthesised by enzymic transfer of GalNAc from UDP-GalNAc to 3-sialyllactose (NeuAc2-3Galß1-4Glc) and 3-sialyl-N-acetyllactosamine (NeuAc2-3Galß1-4GlcNAc). The structures of the products were established by methylation and1H-500 MHz NMR spectroscopy. In Sda serological tests the product formed with 3-sialyl-N-acetyllactosamine was highly active whereas that formed with 3-sialyllactose had only weak activity.  相似文献   
90.
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