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Impact of COVID-19 infection experience on mental health status of intensive care unit patients' family members: a real-world study. QJM 2023; 116:903-910. [PMID: 37498557 DOI: 10.1093/qjmed/hcad184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 07/05/2023] [Indexed: 07/28/2023] Open
Abstract
PURPOSE Family members of patients hospitalized in intensive care unit (ICU) are susceptible to adverse psychological outcomes. However, there is a paucity of studies specifically examining the mental health symptoms in ICU patients' family members with a prior history of coronavirus disease 2019 (COVID-19) infection. AIM This study aimed to investigate mental health status and its influencing factors of ICU patients' family members with previous COVID-19 infection experience in China. DESIGN Nationwide, cross-sectional cohort of consecutive participants of family members of ICU patients from 10 provinces randomly selected in mainland China conducted between October 2022 and May 2023. METHODS The basic information scale, Self-rating depression scale, Self-rating Anxiety Scale, Impact of Event Scale-Revised, Pittsburgh sleep quality index, Perceived Stress Scale, Connor-Davidson resilience scale, Simplified Coping Style Questionnaire were employed to explore mental health status among participants. RESULTS A total of 463 participants, comprising 156 individuals in Covid-19 family member cohort (infection group) and 307 individuals in control family member cohort (control group), met inclusion criteria. The infection group exhibited significantly higher incidence of composite mental health symptoms compared to control group (P = 0.017). Multivariable logistic regression analysis revealed that being female, engaging in physical/mental labor, residing in rural areas, and having children were identified as risk factors for the development of depression, anxiety, and post-traumatic stress disorder symptoms, while medical history of surgery was protective factor. A predictive model demonstrated a favorable discriminative ability and excellent calibration. CONCLUSION COVID-19 infection experience regarded as new traumatic stressors worsen mental health status of ICU patients' family members.
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Selection of gait parameters during constrained walking. Hum Mov Sci 2023; 89:103086. [PMID: 37119660 DOI: 10.1016/j.humov.2023.103086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 03/17/2023] [Accepted: 04/03/2023] [Indexed: 05/01/2023]
Abstract
It is commonly thought that at prescribed speeds humans choose gait parameters that minimize the cost of transportation. However, it is unclear whether and how the relationship between step length and step frequency is affected by the additional physiological factors caused by constraints. We performed a series of experiments to understand the selection of gait parameters under different constraints from a probabilistic perspective. First, we show that the effect of constraining step length on step frequency (i.e., monotonically decrease, Experiment I) is different from the effect of constraining step frequency on step length (i.e., inverted-U, Experiment II). Using the results from Experiment I and II, we summarized the marginal distribution of step length and step frequency and built their joint distribution in a probabilistic model. The probabilistic model predicts the selection of gait parameters by achieving the maximum probability of joint distribution of step length and step frequency. In Experiment III, the probabilistic model could well predict gait parameters at prescribed speeds, and it is similar to minimizing the cost of transportation. Finally, we show that the distribution of step length and step frequency were completely different between constrained and non-constrained walking. We argue that constraints in walking are major factors determining how humans choose gait parameters due to their involvement of mediators, i.e., attention or active control. Using the probabilistic model to account for gait parameters has an advantage compared with fixed-parameter models in that it can still include the effect of hidden mechanical, neurophysiological, or psychological variables by grouping them into distribution curves.
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Aortic stiffness increases during prolonged sitting independent of intermittent standing or prior exercise. Eur J Appl Physiol 2023; 123:533-546. [PMID: 36334128 DOI: 10.1007/s00421-022-05079-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 10/13/2022] [Indexed: 11/07/2022]
Abstract
INTRODUCTION Adverse vascular responses can occur during prolonged sitting, including stiffening of the aortic artery which may contribute to cardiovascular disease. Few studies have investigated the impact of intermittent standing and/or prior exercise as strategies to attenuate these potentially deleterious vascular changes. PURPOSE To investigate central vascular health responses during prolonged sitting, with and without intermittent standing and/or prior exercise. METHODS Fifteen males aged 18 to 31 years were recruited. Subjects completed a control condition [Sitting Only (SO)], and three randomized strategy conditions [Sitting Plus Standing (SSt), Exercise Plus Sitting (ES), Exercise Plus Sitting Plus Standing (ESSt)]. For all conditions, measurements of carotid-femoral pulse wave velocity (cfPWV) were taken at pre- and post-intervention, and brachial and central blood pressure (BP) at pre-, 1-h, 2-h, and 3-h intervention. RESULTS cfPWV significantly increased from pre- to post-intervention for all conditions (all p ≤ 0.043), as did brachial mean arterial pressure (MAP) and diastolic BP, and central MAP and diastolic BP for the control condition (all p ≤ 0.022). Brachial and central systolic BP were significantly higher during SO compared to ESSt at 1 h, and compared to ES for central systolic BP (all p ≤ 0.036). CONCLUSIONS Strategies of intermittent standing and/or prior exercise may not prevent aortic stiffening during sitting but may attenuate BP elevations in the brachial and aortic arteries. Future research should investigate causal mechanistic links between sitting and aortic stiffening, and other attenuation strategies.
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The validity of using one force platform to quantify whole-body forces, velocities, and power during a plyometric push-up. BMC Sports Sci Med Rehabil 2021; 13:103. [PMID: 34462003 PMCID: PMC8406610 DOI: 10.1186/s13102-021-00330-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 08/20/2021] [Indexed: 11/10/2022]
Abstract
Background Previous studies have typically measured velocity and power parameters during the push-up, either using one or two force platforms. The purpose of the study was to compare the force, velocity, and power parameters between the one-force-platform method and the two-force-platform method during plyometric push-ups. Methods Thirty-four physically active young adults participated in the study to perform the plyometric push-up. For the two-force-platform calculation method, the forces applied to the feet and hands were both measured. For the one-force-platform calculation method, the forces applied to the feet were assumed to be constant, while the forces applied to hands were measured by one force platform. Whole-body linear velocities were calculated based on the impulse and momentum theorem. Whole-body power was calculated as the product of the whole-body forces and velocities. Results The one-force-platform method overestimated the whole-body velocities and power compared with the two-force-platform method (1.39 ± 0.37 m/s vs. 0.90 ± 0.23 m/s, Cohen’s d = 1.59, p < 0.05; 1.63 ± 0.47 W/body weight vs. 1.03 ± 0.29 W/body weight, Cohen’s d = 1.49, p < 0.05). These differences were caused by the decreased forces applied to the feet compared to the initial value throughout most of the push-up phase. Large to perfect correlations (r = 0.55 – 0.99) were found for most variables between the two-force-platform and one-force-platform methods. Previous findings of push-up velocities and power using the two-force-platform and one-force-platform methods should be compared with caution. While the two-force-platform method is recommended, linear regression equations may be used to predict velocities and power parameters obtained from one force platform. Conclusions For those professionals who need to accurately quantify kinetic variables during the plyometric push-up, the two-force-platform method should be considered.
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Gender differences in the associations of multiple psychiatric and chronic conditions with major depressive disorder among patients with opioid use disorder. J Addict Dis 2021; 40:168-178. [PMID: 34328394 DOI: 10.1080/10550887.2021.1957639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
PURPOSE The study examined the associations of multiple psychiatric and chronic conditions with the self-reported history of major depressive disorder (MDD) among patients with opioid use disorder (OUD) and tested whether the associations differed by gender. METHODS We conducted a secondary data analysis of baseline data from a clinical trial including 1,646 participants with OUD, of which 465 had MDD. A variable cluster analysis was used to classify chronic medical and psychiatric conditions. Multivariable logistic regression analyses were used to estimate their associations with MDD in subjects with OUD. RESULTS Nine variables were divided into three clusters: cluster 1 included heart condition, hypertension, and liver problems; cluster 2 included gastrointestinal (GI) problems and head injury, and cluster 3 included anxiety disorder, bipolar disorder, and schizophrenia. The overall prevalence of MDD in participants with OUD was 28.3% (22.8% for males and 39.5% for females). Gender, anxiety disorder, schizophrenia, liver problems, heart condition, GI problems, and head injury were significantly associated with MDD. Gender-stratified analyses showed that bipolar disorder, liver problems and individuals with one chronic condition were associated with MDD only in males, whereas heart condition, hypertension, and GI problems were associated with MDD only in females. In addition, anxiety disorder, head injury, individuals with one or more than two psychiatric conditions, and individuals with more than two chronic conditions were associated with MDD regardless of gender. CONCLUSIONS Treatment plans in patients with OUD should not only address MDD but also co-morbid psychiatric and chronic medical conditions that occur with MDD.
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Baseline Assessments of Strength and Balance Performance and Bilateral Asymmetries in Collegiate Athletes. J Strength Cond Res 2020; 33:3015-3029. [PMID: 29985219 DOI: 10.1519/jsc.0000000000002687] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Dai, B, Layer, J, Vertz, C, Hinshaw, T, Cook, R, Li, Y, and Sha, Z. Baseline assessments of strength and balance performance and bilateral asymmetries in collegiate athletes. J Strength Cond Res 33(11): 3015-3029, 2019-Injuries to upper and lower extremities comprise more than 70% of the total injuries in collegiate athletes. Establishing normative data of upper and lower extremity strength and balance may help guide postinjury rehabilitation and return-to-play decisions. The purposes of the current study were to develop the normative data of performance and bilateral asymmetries during 4 upper and lower extremity strength and balance tests in collegiate athletes and to quantify the correlations between strength and balance performance and bilateral asymmetries. A total of 304 male and 195 female Division I athletes from 14 sports performed a maximum push-up test to assess upper extremity strength, a countermovement jump test to assess lower extremity strength, an upper extremity reaching test to assess upper extremity balance, and a lower extremity reaching test to assess lower extremity balance. Bilateral ground reaction forces were collected for the push-up and jump tests. Reaching distances were measured for the 2 balance tests. Bilateral asymmetries were generally less than 10%. Significant sports effects were observed for all 5 performance variables (p < 0.001) but not for asymmetry variables (p ≥ 0.36). Weak correlations were found between strength and balance performance and asymmetries (r < 0.3). Normative data are sex and sports specific in collegiate athletes. Increased asymmetries could be more individualized rather than sex and sports specific. When return-to-play decisions are made, athletes following injuries need to demonstrate less than 10% of asymmetries to be consistent with the normative data. Strength and balance should be evaluated and improved with specific focuses.
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Effect of External Loading on Force and Power Production During Plyometric Push-ups. J Strength Cond Res 2018; 32:1099-1108. [DOI: 10.1519/jsc.0000000000001953] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Efficient androst-1,4-diene-3,17-dione production by co-expressing 3-ketosteroid-Δ 1 -dehydrogenase and catalase in Bacillus subtilis. J Appl Microbiol 2017; 122:119-128. [PMID: 27797429 DOI: 10.1111/jam.13336] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 10/11/2016] [Accepted: 10/17/2016] [Indexed: 01/02/2023]
Abstract
AIMS 3-ketosteroid-Δ1 -dehydrogenase (KSDD), a flavin adenine dinucleotide (FAD)-dependent enzyme involved in sterol metabolism, specifically catalyses the conversion of androst-4-ene-3,17-dione (AD) to androst-1,4-diene-3,17-dione (ADD). However, the low KSDD activity and the toxic effects of hydrogen peroxide (H2 O2 ) generated during the biotransformation of AD to ADD with FAD regeneration hinder its application on AD conversion. The aim of this work was to improve KSDD activity and eliminate the toxic effects of the generated H2 O2 to enhance ADD production. METHODS AND RESULTS The ksdd gene obtained from Mycobacterium neoaurum JC-12 was codon-optimized to increase its expression level in Bacillus subtilis, and the KSDD activity reached 12·3 U mg-1 , which was sevenfold of that of codon-unoptimized gene. To improve AD conversion, catalase was co-expressed with KSDD in B. subtilis 168/pMA5-ksddopt -katA to eliminate the toxic effects of H2 O2 generated during AD conversion. Finally, under optimized bioconversion conditions, fed-batch strategy was carried out and the ADD yield improved to 8·76 g l-1 . CONCLUSIONS This work demonstrates the potential to improve enzyme activity by codon-optimization and eliminate the toxic effects of H2 O2 by co-expressing catalase. SIGNIFICANCE AND IMPACT OF THE STUDY This study showed the highest ADD productivity ever reported and provides a promising strain for efficient ADD production in the pharmaceutical industry.
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Principal Component Regression Analysis of Nutrition Factors and Physical Activities with Diabetes. ACTA ACUST UNITED AC 2017. [DOI: 10.4172/2155-6180.1000364] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Generalized Linear Mixed Model Analysis of Urban-Rural Differences in Social and Behavioral Factors for Colorectal Cancer Screening. Asian Pac J Cancer Prev 2017; 18:2581-2589. [PMID: 28952708 PMCID: PMC5720670 DOI: 10.22034/apjcp.2017.18.9.2581] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Objective: Screening for colorectal cancer (CRC) can reduce disease incidence, morbidity, and mortality. However, few studies have investigated the urban-rural differences in social and behavioral factors influencing CRC screening. The objective of the study was to investigate the potential factors across urban-rural groups on the usage of CRC screening. Methods: A total of 38,505 adults (aged ≥40 years) were selected from the 2009 California Health Interview Survey (CHIS) data - the latest CHIS data on CRC screening. The weighted generalized linear mixed-model (WGLIMM) was used to deal with this hierarchical structure data. Weighted simple and multiple mixed logistic regression analyses in SAS ver. 9.4 were used to obtain the odds ratios (ORs) and their 95% confidence intervals (CIs). Results: The overall prevalence of CRC screening was 48.1% while the prevalence in four residence groups - urban, second city, suburban, and town/rural, were 45.8%, 46.9%, 53.7% and 50.1%, respectively. The results of WGLIMM analysis showed that there was residence effect (p<0.0001) and residence groups had significant interactions with gender, age group, education level, and employment status (p<0.05). Multiple logistic regression analysis revealed that age, race, marital status, education level, employment stats, binge drinking, and smoking status were associated with CRC screening (p<0.05). Stratified by residence regions, age and poverty level showed associations with CRC screening in all four residence groups. Education level was positively associated with CRC screening in second city and suburban. Infrequent binge drinking was associated with CRC screening in urban and suburban; while current smoking was a protective factor in urban and town/rural groups. Conclusions: Mixed models are useful to deal with the clustered survey data. Social factors and behavioral factors (binge drinking and smoking) were associated with CRC screening and the associations were affected by living areas such as urban and rural regions.
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289O The promise of PET/CT-based bone marrow assessment in replacing routine bone marrow biopsy for staging and prognosis of extranodal natural killer/T-cell lymphoma. Ann Oncol 2015. [DOI: 10.1093/annonc/mdv526.05] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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High expression of kinesin light chain-2, a novel target of miR-125b, is associated with poor clinical outcome of elderly non-small-cell lung cancer patients. Br J Cancer 2015; 112:874-82. [PMID: 25668010 PMCID: PMC4453958 DOI: 10.1038/bjc.2015.3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2014] [Revised: 12/07/2014] [Accepted: 12/20/2014] [Indexed: 01/11/2023] Open
Abstract
Background: MiR-125b has critical role in non-small-cell lung cancer (NSCLC) cell migration, and its target genes have not been elucidated. Kinesin-1 light chain (KLC)-2 was predicted as one of miR-125b's targets by bioinformatics analysis. This study is to identify the function of KLC2 and its interaction with miR-125b in NSCLC. Methods: Kinesin-1 light chain-2 protein expression and its clinical relevance were analysed in 140 matched NSCLC and adjacent non-neoplastic lung tissues. Both KLC2 gain- and loss-of-function analyses were performed in NSCLC cell lines by transient transfection. The direct interaction between KLC2 and miR-125b was confirmed by a luciferase reporter assay and a transient co-transfection assay as well as an analysis of eight matched clinical samples. Results: KLC2 protein was upregulated in NSCLC cell lines and tissues, and was an independent predictor of poor prognosis for elderly NSCLC patients. Kinesin-1 light chain-2 remarkably enhanced the invasive and migratory ability of NSCLC cells. MiR-125b inhibited KLC2 3′-untranslated region luciferase activity and protein expression, and inversely correlated with KLC2 expression in clinical samples. Kinesin-1 light chain-2 almost completely reversed miR-125b-induced inhibition on migration and invasion. Conclusions: Kinesin-1 light chain-2 protein overexpression predicts poor survival in elderly NSCLC patients. Kinesin-1 light chain-2 acts as a proto-oncogene and a functional target of miR-125b in NSCLC cells.
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The TLR9 ligand, CpG-ODN, induces protection against cerebral ischemia/reperfusion injury via activation of PI3K/Akt signaling. J Am Heart Assoc 2014; 3:e000629. [PMID: 24721797 PMCID: PMC4187520 DOI: 10.1161/jaha.113.000629] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 02/22/2014] [Indexed: 12/20/2022]
Abstract
BACKGROUND Toll-like receptors (TLRs) have been shown to be involved in cerebral ischemia/reperfusion (I/R) injury. TLR9 is located in intracellular compartments and recognizes CpG-DNA. This study examined the effect of CpG-ODN on cerebral I/R injury. METHODS AND RESULTS C57BL/6 mice were treated with CpG-ODN by i.p. injection 1 hour before the mice were subjected to cerebral ischemia (60 minutes) followed by reperfusion (24 hours). Scrambled-ODN served as control-ODN. Untreated mice, subjected to cerebral I/R, served as I/R control. The effect of inhibitory CpG-ODN (iCpG-ODN) on cerebral I/R injury was also examined. In addition, we examined the therapeutic effect of CpG-ODN on cerebral I/R injury by administration of CpG-ODN 15 minutes after cerebral ischemia. CpG-ODN administration significantly decreased cerebral I/R-induced infarct volume by 69.7% (6.4±1.80% vs 21.0±2.85%, P<0.05), improved neurological scores, and increased survival rate, when compared with the untreated I/R group. Therapeutic administration of CpG-ODN also significantly reduced infarct volume by 44.7% (12.6±2.03% vs 22.8±2.54%, P<0.05) compared with untreated I/R mice. Neither control-ODN, nor iCpG-ODN altered I/R-induced cerebral injury or neurological deficits. Nissl staining showed that CpG-ODN treatment preserved neuronal morphology in the ischemic hippocampus. Immunoblot showed that CpG-ODN administration increased Bcl-2 levels by 41% and attenuated I/R-increased levels of Bax and caspase-3 activity in ischemic brain tissues. Importantly, CpG-ODN treatment induced Akt and GSK-3β phosphorylation in brain tissue and cultured microglial cells. PI3K inhibition with LY294002 abolished CpG-ODN-induced protection. CONCLUSION CpG-ODN significantly reduces cerebral I/R injury via a PI3K/Akt-dependent mechanism. Our data also indicate that CpG-ODN may be useful in the therapy of cerebral I/R injury.
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Ultrahigh-Field MR Volumetry of the Endopiriform Nucleus in Temporal Lobe Epilepsy (P03.110). Neurology 2012. [DOI: 10.1212/wnl.78.1_meetingabstracts.p03.110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Generation and analysis of 10 000 ESTs from the half-smooth tongue sole Cynoglossus semilaevis and identification of microsatellite and SNP markers. JOURNAL OF FISH BIOLOGY 2010; 76:1190-1204. [PMID: 20409170 DOI: 10.1111/j.1095-8649.2010.02592.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Three normalized cDNA libraries were constructed, two of which were constructed from reproductive tissues ovary and testis, and the other one from pooled immune tissues including head kidney, intestine, liver and spleen. A total of 10 542 clones were sequenced generating 10 128 expressed sequence tags (ESTs). Cluster analysis indicated a total of 5808 unique sequences including 1712 contigs and 4096 singletons. A total of 4249 (73%) of the unique ESTs had significant hits to the non-redundant protein database, 2253 of which were annotated using Gene Ontology (GO) terms. A total of 311 microsatellites (with 246 having sufficient flanking sequences for primer design) and 6294 putative SNPs were identified. These genome resources provide the material basis for future microarray development, marker validation and genetic linkage and QTL analysis.
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Multi-Phase-Multi-Size-Group Model for the Inclusion of Population Balances into the CFD Simulation of Gas-Liquid Bubbly Flows. Chem Eng Technol 2006. [DOI: 10.1002/ceat.200500386] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Application of CFD simulation to suspension crystallization—factors affecting size-dependent classification. POWDER TECHNOL 2001. [DOI: 10.1016/s0032-5910(01)00369-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
All aerobic organisms have mechanisms that protect against oxidative compounds. Catalase, peroxidase, superoxide dismutase, glutathione, and thioredoxin are widely distributed in many taxa and constitute elements of a nearly ubiquitous antioxidant metabolic strategy. Interestingly, the regulatory mechanisms that control these elements are rather different depending on the nature of the oxidative stress and the organism. Catalase is well documented to play an important role in protecting cells from oxidative stress. In particular, pathogenic bacteria seem to use this enzyme as a defensive tool against attack by the host. To investigate the significance of catalase in hostile environments, we made catalase deletion mutations in two different B. abortus strains and used two-dimensional gel analysis, survival tests, and adaptation experiments to explore the behavior and role of catalase under several oxidative stress conditions. These studies show that B. abortus strains that do not express catalase activity exhibit increased sensitivity to hydrogen peroxide. We also demonstrate that catalase expression is regulated in this species, and that preexposure to a sublethal concentration of hydrogen peroxide allows B. abortus to adapt so as to survive subsequent exposure to higher concentrations of hydrogen peroxide.
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Abstract
Through cognate interaction between antigen-specific B-cell and CD4(+) alphabeta T cells, the CD4(+) alphabeta T cells secrete cytokines that initiate immunoglobulin (Ig) class switching from IgM to IgG. In this study, we show that formalin-inactivated influenza PR8 virus induces virus-specific IgM and IgG responses in the absence of CD4(+) T cells and that all four subclasses of IgG are produced. The immunized CD4-deficient mice were also found to be completely protected against lethal infection with live, pathogenic influenza virus. The ability of CD4(+) T-cell-deficient mice to generate these IgG responses was not found to be impaired when these mice were depleted of CD8(+) T cells with an anti-CD8 monoclonal antibody. In contrast, alphabeta T-cell-deficient mice (TCRbeta(-/-)) were not found to produce significant amounts of IgG upon immunization with formalin-inactivated PR8 virus. These results suggest that CD4(-) CD8(-) double-negative alphabeta T cells are playing a role in regulating Ig class switching in the absence of CD4(+) T cells.
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[Re-evaluation of proteinuria and qualitive methods for diagnosis of diabetic nephropathy]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 2000; 31:88-90. [PMID: 12501624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
This study was aimed to re-evaluate the proteinuria quantitative and qualitative methods for diagnosis of diabetic nephropathy (DN). 136 cases were divided into two groups of proteinuria negativeness and postiveness by the results of urine routine examination. The clinical and biochemical indices and the frequencies of other diabetic complications of the two groups were compared. The results showed that the blood glucose and glycated Hb in the two groups were increased, especially in the proteinuria negative group (P < 0.01 and 0.05, respectively). There was a high prevalence of hypertension and other diabetic complications in the two groups, and it was higher in the positive group than in the negative group (P < 0.05 and 0.01, respectively). The frequencies of hyperlipoproteinemia in the two groups were over 40%, but no significant defference was observed between them (P > 0.05). There was correlation between hypertension and proteinuria (P < 0.01) but no correlation between diabetic retinopathy and proteinuria. The prevalence of azotemia in the proteinuria negative group was 17.07%. These suggest that the amount of proteinuria can not completely reflect the duration and severity of DN. Negative proteinuria in routine examination cannot rule out DN. For diagnosis of DN, it is necessary to think about all data on blood glucose, blood lipid, blood pressure and the change in fundus oculi.
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Enhancement of mucosal immune responses to the influenza virus HA protein by alternative approaches to DNA immunization. Immunobiology 1999; 200:21-30. [PMID: 10084693 DOI: 10.1016/s0171-2985(99)80030-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
DNA immunization provides many advantages as an approach to prevent infectious diseases. However, although previous studies using this approach have demonstrated immune responses in serum, they were not successful in inducing significant levels of antibodies in secretions. In this study, plasmid DNAs expressing the influenza virus hemagglutinin glycoprotein have been evaluated for their ability to induce antibody responses in serum and saliva when used alone or along with either liposomes or bioadhesive polymers as mucosal delivery vehicles. Significant levels of virus-specific Ig in serum as well as secretory IgA in saliva were detected in mice following mucosal DNA immunization. These antibodies were found to block the infectivity of the virus using a plaque reduction assay. Our findings thus indicate that mucosal DNA immunization with specific delivery systems can elicit virus-specific antibody responses in serum as well as IgA responses at mucosal surfaces.
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Abstract
A periplasmic catalase has been purified and cloned from Brucella abortus. The functional enzyme is a tetramer with a subunit molecular weight of 55,000. All evidence indicates that a typical N-terminal signal sequence is not associated with the export of this protein to the periplasm.
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Abstract
Two types of superoxide dismutase (SOD) have been found in Brucella abortus, a cytosolic Mn-SOD and a Cu/Zn-SOD of unknown location. We sought to determine the subcellular location of Cu/Zn-SOD in B. abortus ST 19. We report a modified spheroplasting procedure for the release of periplasmic contents from B. abortus cells using a dipolar ionic detergent, Zwittergent 316. This detergent, used in place of EDTA, destabilizes the outer membrane sufficiently to allow penetration of lysozyme and the subsequent selective release of periplasmic proteins by osmotic shock. Cytoplasmic cross-contamination of periplasmic fractions was assessed by assaying for malate dehydrogenase activity. Cyanide-sensitive and cyanide-insensitive SOD activity was measured by both the xanthine oxidase-cytochrome c method and a hematoxylin assay. Results suggest that B. abortus Cu/Zn-SOD activity is periplasmic. This zwittergent-lysozyme extraction procedure may be applicable to the separation, isolation and characterization of many other periplasmic proteins of B. abortus and other Gram-negative organisms especially when cytosolic contamination is undesirable.
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[Identification of Chinese drugs by fluorescence spectrum]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1991; 16:326-8, 381. [PMID: 1786090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Cortex Fraxini, Radix et Rhizoma Rhei, Semen Astragali Complanati, Semen Lini, Bulbus Fritillariae Cirrhosae, Bulbus Fritillariae Thunbergii and their confused medicinal materials have been identified by the fluorescence spectrum. This is a referential method for the identification of Chinese drugs.
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[Quantitative determination of strychnine and brucine in semen Strychni and its preparations by gas chromatography]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1990; 15:670-1, 703. [PMID: 1980818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Contents of strychnine and brucine in dry seeds of Strychnos nux-vomica and its preparations were determined by gas chromatography. The determination conditions were:support Gas Chrom Q; liquid phase 3% OV-101; stainless steel column 0.5 m x 3 mm; column temperature 265 degrees C; FID detector.
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