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171.
Background
The difference between total serum protein and albumin, i.e. the gamma gap, is a frequently used clinical screening measure for both latent infection and malignancy. However, there are no studies defining a positive gamma gap. Further, whether it is an independent risk factor of mortality is unknown.Methods and Findings
This study examined the association between gamma gap, all-cause mortality, and specific causes of death (cardiovascular, cancer, pulmonary, or other) in 12,260 participants of the National Health and Nutrition Examination Survey (NHANES) from 1999–2004. Participants had a comprehensive metabolic panel measured, which was linked with vital status data from the National Death Index. Cause of death was based on ICD10 codes from death certificates. Analyses were performed with Cox proportional hazards models adjusted for mortality risk factors. The mean (SE) age was 46 (0.3) years and the mean gamma gap was 3.0 (0.01) g/dl. The population was 52% women and 10% black. During a median follow-up period of 4.8 years (IQR: 3.3 to 6.2 years), there were 723 deaths. The unadjusted 5-year cumulative incidences across quartiles of the gamma gap (1.7–2.7, 2.8–3.0, 3.1–3.2, and 3.3–7.9 g/dl) were 5.7%, 4.2%, 5.5%, and 7.8%. After adjustment for risk factors, participants with a gamma gap of ≥3.1 g/dl had a 30% higher risk of death compared to participants with a gamma gap <3.1 g/dl (HR: 1.30; 95%CI: 1.08, 1.55; P = 0.006). Gamma gap (per 1.0 g/dl) was most strongly associated with death from pulmonary causes (HR 2.22; 95%CI: 1.19, 4.17; P = 0.01).Conclusions
The gamma gap is an independent risk factor for all-cause mortality at values as low as 3.1 g/dl (in contrast to the traditional definition of 4.0 g/dl), and is strongly associated with death from pulmonary causes. Future studies should examine the biologic pathways underlying these associations. 相似文献172.
Edgar Morales-Rios Ian N. Watt Qifeng Zhang Shujing Ding Ian M. Fearnley Martin G. Montgomery Michael J. O. Wakelam John E. Walker 《Open biology》2015,5(9)
The structures of F-ATPases have been determined predominantly with mitochondrial enzymes, but hitherto no F-ATPase has been crystallized intact. A high-resolution model of the bovine enzyme built up from separate sub-structures determined by X-ray crystallography contains about 85% of the entire complex, but it lacks a crucial region that provides a transmembrane proton pathway involved in the generation of the rotary mechanism that drives the synthesis of ATP. Here the isolation, characterization and crystallization of an integral F-ATPase complex from the α-proteobacterium Paracoccus denitrificans are described. Unlike many eubacterial F-ATPases, which can both synthesize and hydrolyse ATP, the P. denitrificans enzyme can only carry out the synthetic reaction. The mechanism of inhibition of its ATP hydrolytic activity involves a ζ inhibitor protein, which binds to the catalytic F1-domain of the enzyme. The complex that has been crystallized, and the crystals themselves, contain the nine core proteins of the complete F-ATPase complex plus the ζ inhibitor protein. The formation of crystals depends upon the presence of bound bacterial cardiolipin and phospholipid molecules; when they were removed, the complex failed to crystallize. The experiments open the way to an atomic structure of an F-ATPase complex. 相似文献
173.
Application of an aqueous two‐phase micellar system to extract bromelain from pineapple (Ananas comosus) peel waste and analysis of bromelain stability in cosmetic formulations
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Lívia Genovez Spir Janaína Artem Ataide Letícia Celia De Lencastre Novaes Daniela De Borba Gurpilhares Patrícia Moriel Edgar Silveira Adalberto Pessoa Jr. Elias Basile Tambourgi Priscila Gava Mazzola 《Biotechnology progress》2015,31(4):937-945
Bromelain is a set of proteolytic enzymes found in pineapple (Ananas comosus) tissues such as stem, fruit and leaves. Because of its proteolytic activity, bromelain has potential applications in the cosmetic, pharmaceutical, and food industries. The present study focused on the recovery of bromelain from pineapple peel by liquid–liquid extraction in aqueous two‐phase micellar systems (ATPMS), using Triton X‐114 (TX‐114) and McIlvaine buffer, in the absence and presence of electrolytes CaCl2 and KI; the cloud points of the generated extraction systems were studied by plotting binodal curves. Based on the cloud points, three temperatures were selected for extraction: 30, 33, and 36°C for systems in the absence of salts; 40, 43, and 46°C in the presence of KI; 24, 27, and 30°C in the presence of CaCl2. Total protein and enzymatic activities were analyzed to monitor bromelain. Employing the ATPMS chosen for extraction (0.5 M KI with 3% TX‐114, at pH 6.0, at 40°C), the bromelain extract stability was assessed after incorporation into three cosmetic bases: an anhydrous gel, a cream, and a cream‐gel formulation. The cream‐gel formulation presented as the most appropriate base to convey bromelain, and its optimal storage conditions were found to be 4.0 ± 0.5°C. The selected ATPMS enabled the extraction of a biomolecule with high added value from waste lined‐up in a cosmetic formulation, allowing for exploration of further cosmetic potential. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:937–945, 2015 相似文献
174.
Vincent Kayina Samuel Kyobe Fred A. Katabazi Edgar Kigozi Moses Okee Beatrice Odongkara Harriet M. Babikako Christopher C. Whalen Moses L. Joloba Philippa M. Musoke Ezekiel Mupere 《PloS one》2015,10(4)
Background
We determined prevalence of pertussis infection and its associated host and environmental factors to generate information that would guide strategies for disease control.Methods
In a cross-sectional study, 449 children aged 3 months to 12 years with persistent cough lasting ≥14 days were enrolled and evaluated for pertussis using DNA polymerase chain reaction (PCR) and ELISA serology tests.Results
Pertussis prevalence was 67 (15% (95% Confidence Interval (CI): 12–18)) and 81 (20% (95% CI: 16–24)) by PCR and ELISA, respectively among 449 participating children. The prevalence was highest in children with >59 months of age despite high vaccination coverage of 94% in this age group. Study demographic and clinical characteristics were similar between pertussis and non-pertussis cases. Of the 449 children, 133 (30%) had a coughing household member and 316 (70%) did not. Among 133 children that had a coughing household member, sex of child, sharing bed with a coughing household member and having a coughing individual in the neighborhood were factors associated with pertussis. Children that had shared a bed with a coughing household individual had seven-fold likelihood of having pertussis compared to children that did not (odds ratio (OR) 7.16 (95% CI: 1.24–41.44)). Among the 316 children that did not have a coughing household member, age <23 months, having or contact with a coughing individual in neighborhood, a residence with one room, and having a caretaker with >40 years of age were the factors associated with pertussis. Age <23months was three times more likely to be associated with pertussis compared to age 24–59 months (OR 2.97 (95% CI: 1.07–8.28)).Conclusion
Findings suggest high prevalence of pertussis among children with persistent cough at a health facility and it was marked in children >59 months of age, suggesting the possibility of waning immunity. The factors associated with pertussis varied by presence or absence of a coughing household member. 相似文献175.
Background & Aims
The brain dopaminergic (DA) system is involved in fine tuning many behaviors and several human diseases are associated with pathological alterations of the DA system such as Parkinson’s disease (PD) and drug addiction. Because of its complex network integration, detailed analyses of physiological and pathophysiological conditions are only possible in a whole organism with a sophisticated tool box for visualization and functional modification.Methods & Results
Here, we have generated transgenic mice expressing the tetracycline-regulated transactivator (tTA) or the reverse tetracycline-regulated transactivator (rtTA) under control of the tyrosine hydroxylase (TH) promoter, TH-tTA (tet-OFF) and TH-rtTA (tet-ON) mice, to visualize and genetically modify DA neurons. We show their tight regulation and efficient use to overexpress proteins under the control of tet-responsive elements or to delete genes of interest with tet-responsive Cre. In combination with mice encoding tet-responsive luciferase, we visualized the DA system in living mice progressively over time.Conclusion
These experiments establish TH-tTA and TH-rtTA mice as a powerful tool to generate and monitor mouse models for DA system diseases. 相似文献176.
Eira Valeria Barrón Edgar Roman-Bassaure Ana Laura Sánchez-Sandoval Ana María Espinosa Mariano Guardado-Estrada Ingrid Medina Eligia Juárez Ana Alfaro Miriam Bermúdez Rubén Zamora Carlos García-Ruiz Juan Carlos Gomora Susana Kofman E. Martha Pérez-Armendariz Jaime Berumen 《PloS one》2015,10(9)
The cyclin-dependent kinase inhibitor 3 (CDKN3) gene, involved in mitosis, is upregulated in cervical cancer (CC). We investigated CDKN3 mRNA as a survival biomarker and potential therapeutic target for CC. CDKN3 mRNA was measured in 134 CC and 25 controls by quantitative PCR. A 5-year survival study was conducted in 121 of these CC patients. Furthermore, CDKN3-specific siRNAs were used to investigate whether CDKN3 is involved in proliferation, migration, and invasion in CC-derived cell lines (SiHa, CaSki, HeLa). CDKN3 mRNA was on average 6.4-fold higher in tumors than in controls (p = 8 x 10−6, Mann-Whitney). A total of 68.2% of CC patients over expressing CDKN3 gene (fold change ≥ 17) died within two years of diagnosis, independent of the clinical stage and HPV type (Hazard Ratio = 5.0, 95% CI: 2.5–10, p = 3.3 x 10−6, Cox proportional-hazards regression). In contrast, only 19.2% of the patients with lower CDKN3 expression died in the same period. In vitro inactivation of CDKN3 decreased cell proliferation on average 67%, although it had no effect on cell migration and invasion. CDKN3 mRNA may be a good survival biomarker and potential therapeutic target in CC. 相似文献
177.
Edgar Arrua Vares Giovanni Abrah?o Salum Lucas Spanemberg Marco Ant?nio Caldieraro Marcelo P. Fleck 《PloS one》2015,10(8)
Background
Several studies have recognized that depression is a multidimensional construct, although the scales that are currently available have been shown to be limited in terms of the ability to investigate the multidimensionality of depression. The objective of this study is to integrate information from instruments that measure depression from different perspectives–a self-report symptomatic scale, a clinician-rated scale, and a clinician-rated scale of depressive signs–in order to investigate the multiple dimensions underlying the depressive construct.Methods
A sample of 399 patients from a mood disorders outpatient unit was investigated with the Beck Depression Inventory (BDI), the Hamilton Depression Rating Scale (HDRS), and the Core Assessment of Psychomotor Change (CORE). Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA) were used to investigate underlying dimensions of depression, including item level analysis with factor loadings and item thresholds.Results
A solution of six depression dimensions has shown good-fit to the data, with no cross-loading items, and good interpretability. Item-level analysis revealed that the multidimensional depressive construct might be organized into a continuum of severity in the following ascending order: sexual, cognitive, insomnia, appetite, non-interactiveness/motor retardation, and agitation.Conclusion
An integration of both signs and symptoms, as well as the perspectives of clinicians and patients, might be a good clinical and research alternative for the investigation of multidimensional issues within the depressive syndrome. As predicted by theoretical models of depression, the melancholic aspects of depression (non-interactiveness/motor retardation and agitation) lie at the severe end of the depressive continuum. 相似文献178.
179.
Multidrug resistance ABC transporters in plants are required for polar transport of the hormone auxin (indole-3-acetic acid). They are studied in animals primarily because their overexpression confers resistance to anticancer agents. Immunophilins are studied in both plants and animals for their roles in folding and trafficking of proteins, particularly those with signal transducing functions and susceptibility to immunosuppressant drugs. Previous genetic and molecular studies in Arabidopsis thaliana established a physical and functional interaction between some ABCB transporters and the TWISTED DWARF1 (TWD1) immunophilin. In this work, confocal microscopy of fluorescently tagged TWD1 shows it to reside at the endoplasmic reticulum (ER). Mutations in TWD1 caused mislocalization of ABCB1, ABCB4, and ABCB19 to the ER instead of the plasma membrane as shown by confocal microscopy of fluorescently tagged fusion proteins and transmission electron microscopy of immunogold-labeled samples in the case of ABCB19. Localization of the unrelated PIN-FORMED2 auxin transporter or plasma membrane marker proteins was not affected by loss of TWD1. Abnormal spread of auxin signaling into the elongation zone of twd1 roots, attributable to mislocalized ABCB transporters and suppressed by an auxin transport inhibitor, appeared to cause the twisted cell files characteristic of twd1 roots. 相似文献
180.
China's remarkable economic growth in the last 3 decades has brought about big improvements in quality of life while simultaneously contributing to serious environmental problems. The aim of all economic activities is, ultimately, to provide the population with products and services. Analyzing environmental impacts of consumption can be valuable for illuminating underlying drivers for energy use and emissions in society. This study applies an environmentally extended input‐output analysis to estimate household environmental impact (HEI) of urban Beijing households at different levels of development. The analysis covers direct and indirect energy use and emissions of carbon dioxide (CO2), sulfur dioxide (SO2), and nitrogen oxide (NOx). On the basis of observations of how HEI varies across income groups, prospects for near‐future changes in HEI are discussed. Results indicate that in 2007, an urban resident in Beijing used, on average, 52 gigajoules of total primary energy supply. The corresponding annual emissions were 4.2 tonnes CO2, 27 kilograms SO2, and 17 kilograms NOx. Of this, only 18% to 34% was used or emitted by the households directly. While the overall expenditure elasticity of energy use is around 0.9, there is a higher elasticity of energy use associated with transport. The results suggest that significant growth in HEI can be expected in the near future, even with substantial energy efficiency improvements. 相似文献