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In this study, active and intelligent films were fabricated using M. esculenta starch (MES), gum ghatti (GG) and R. nigrum extract (RNE) and their functionality, physicochemical properties and practical application were assessed. Incorporation of GG decreased water vapor permeability (WVP) (9.73 to 8.91 × 10-11 g m-1 s-1 Pa-1), increased tensile strength (TS) (16.63 to 44.45 MPa) and elongation at break (EAB) (4.47 to 6.82%) of MES film. Incorporation of RNE decreased WVP (8.91 to 7.87 × 10-11 g m-1 s-1 Pa-1) and TS (44.45 to 26.33 MPa) of MES-GG film. MES-GG-RNE films showed enhanced thermal stability, light barrier performance, excellent pH and ammonia sensitivities, strong antioxidant activity, and significant visible color change when monitoring beef freshness. Findings supported the application of this strategy in fabrication of MES-GG-RNE films for active and intelligent packaging. Further study on stability, sustainability and consumer acceptability of films is in progress.
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The pathogen Pseudomonas syringae, responsible for a variety of diseases, poses a considerable threat to global crop yields. Emerging biocontrol strategies employ antagonistic microorganisms, utilizing phyllosphere microecology and systemic resistance to combat this disease. However, the interactions between phyllosphere microbial dynamics and the activation of the plant defense system remain poorly understood. Here we show significant alterations in phyllosphere microbiota structure and plant gene expression following the application of biocontrol agents. We reveal enhanced collaboration and integration of Sphingomonas and Methylobacterium within the microbial co-occurrence network. Notably, Sphingomonas inhibits P. syringae by disrupting pathogen chemotaxis and virulence. Additionally, both Sphingomonas and Methylobacterium activate plant defenses by upregulating pathogenesis-related gene expression through abscisic acid, ethylene, jasmonate acid, and salicylic acid signaling pathways. Our results highlighted that biocontrol agents promote plant health, from reconstructing beneficial microbial consortia to enhancing plant immunity. The findings enrich our comprehension of the synergistic interplays between phyllosphere microbiota and plant immunity, offering potential enhancements in biocontrol efficacy for crop protection.
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Bacteriophages, viruses that specifically target plant pathogenic bacteria, have emerged as a promising alternative to traditional agrochemicals. However, it remains unclear how phages should be applied to achieve efficient pathogen biocontrol and to what extent their efficacy is shaped by indirect interactions with the resident microbiota. Here, we tested if the phage biocontrol efficacy of Ralstonia solanacearum phytopathogenic bacterium can be improved by increasing the phage cocktail application frequency and if the phage efficacy is affected by pathogen-suppressing bacteria already present in the rhizosphere. We find that increasing phage application frequency improves R. solanacearum density control, leading to a clear reduction in bacterial wilt disease in both greenhouse and field experiments with tomato. The high phage application frequency also increased the diversity of resident rhizosphere microbiota and enriched several bacterial taxa that were associated with the reduction in pathogen densities. Interestingly, these taxa often belonged to Actinobacteria known for antibiotics production and soil suppressiveness. To test if they could have had secondary effects on R. solanacearum biocontrol, we isolated Actinobacteria from Nocardia and Streptomyces genera and tested their suppressiveness to the pathogen in vitro and in planta. We found that these taxa could clearly inhibit R. solanacearum growth and constrain bacterial wilt disease, especially when combined with the phage cocktail. Together, our findings unravel an undiscovered benefit of phage therapy, where phages trigger a second line of defense by the pathogen-suppressing bacteria that already exist in resident microbial communities. IMPORTANCE: Ralstonia solanacearum is a highly destructive plant-pathogenic bacterium with the ability to cause bacterial wilt in several crucial crop plants. Given the limitations of conventional chemical control methods, the use of bacterial viruses (phages) has been explored as an alternative biological control strategy. In this study, we show that increasing the phage application frequency can improve the density control of R. solanacearum, leading to a significant reduction in bacterial wilt disease. Furthermore, we found that repeated phage application increased the diversity of rhizosphere microbiota and specifically enriched Actinobacterial taxa that showed synergistic pathogen suppression when combined with phages due to resource and interference competition. Together, our study unravels an undiscovered benefit of phages, where phages trigger a second line of defense by the pathogen-suppressing bacteria present in resident microbial communities. Phage therapies could, hence, potentially be tailored according to host microbiota composition to unlock the pre-existing benefits provided by resident microbiota.
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Bacteriófagos , Microbiota , Doenças das Plantas , Ralstonia solanacearum , Rizosfera , Microbiologia do Solo , Solanum lycopersicum , Ralstonia solanacearum/virologia , Ralstonia solanacearum/fisiologia , Solanum lycopersicum/microbiologia , Solanum lycopersicum/virologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Bacteriófagos/fisiologia , Bacteriófagos/isolamento & purificação , Actinobacteria/virologiaRESUMO
BACKGROUND: Communication skills (CS) represent a core competency in radiology residency training. However, no structured curriculum exists to train radiology residents in CS in China. The aim of this study was to evaluate the status and prevalence of doctor-patient communication training among radiology residents in nine Chinese accredited radiology residency training programs and to determine whether there is a perceived need for a formalized curriculum in this field. METHODS: We administered a cross-sectional online survey to radiology residents involved in CS training at nine standard residency training programs in China. The questionnaire developed for this study included CS training status, residents' demographics, attitudes toward CS training, communication needs, and barriers. Residents' attitudes toward CS training were measured with the Communication Skills Attitude Scale (CSAS) and its subscales, a positive attitude scale (PAS) and negative attitude scale (NAS). RESULTS: A total of 133 (48.36%) residents participated in the survey. The mean total scores on the two dimensions of the CSAS were 47.61 ± 9.35 in the PAS and 36.34 ± 7.75 in the NAS. Factors found to be significantly associated with the PAS included receiving previous training in CS, medical ethics, or humanities and the doctor's attire. We found that first-year residents and poor personal CS were the most influential factors on the NAS. Only 58.65% of participants reported having previously received CS training during medical school, and 72.93% of respondents reported failure in at least one difficult communication during their residency rotation. Most of those surveyed agreed that CS can be learned through courses and were interested in CS training. Some of the most common barriers to implementing formal CS training were a lack of time, no standardized curriculum, and a lack of materials and faculty expertise. CONCLUSIONS: Most residents had a very positive attitude toward CS training and would value further training, despite the limited formal CS training for radiology residents in China. Future efforts should be made to establish and promote a standard and targeted CS curriculum for Chinese radiology residents.
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Comunicação , Internato e Residência , Avaliação das Necessidades , Radiologia , Humanos , Estudos Transversais , China , Masculino , Feminino , Adulto , Radiologia/educação , Inquéritos e Questionários , Atitude do Pessoal de Saúde , Relações Médico-Paciente , Currículo , Competência Clínica/estatística & dados numéricosRESUMO
Cellulosomes are intricate cellulose-degrading multi-enzymatic complexes produced by anaerobic bacteria, which are valuable for bioenergy development and biotechnology. Cellulosome assembly relies on the selective interaction between cohesin modules in structural scaffolding proteins (scaffoldins) and dockerin modules in enzymes. Although the number of tandem cohesins in the scaffoldins is believed to determine the complexity of the cellulosomes, tandem dockerins also exist, albeit very rare, in some cellulosomal components whose assembly and functional roles are currently unclear. In this study, we characterized the structure and mode of assembly of a tandem bimodular double-dockerin, which is connected to a putative S8 protease in the cellulosome-producing bacterium, Clostridium thermocellum. Crystal and NMR structures of the double-dockerin revealed two typical type I dockerin folds with significant interactions between them. Interaction analysis by isothermal titration calorimetry and NMR titration experiments revealed that the double-dockerin displays a preference for binding to the cell-wall anchoring scaffoldin ScaD through the first dockerin with a canonical dual-binding mode, while the second dockerin module was unable to bind to any of the tested cohesins. Surprisingly, the double-dockerin showed a much higher affinity to a cohesin from the CipC scaffoldin of Clostridium cellulolyticum than to the resident cohesins from C. thermocellum. These results contribute valuable insights into the structure and assembly of the double-dockerin module, and provide the basis for further functional studies on multiple-dockerin modules and cellulosomal proteases, thus highlighting the complexity and diversity of cellulosomal components.
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Clostridium thermocellum , Coesinas , Clostridium thermocellum/química , Proteínas de Ciclo Celular/química , Proteínas Cromossômicas não Histona/química , Complexos Multienzimáticos , Proteínas de Bactérias/químicaRESUMO
Depending on various government policies, COVID-19 (Corona Virus Disease-19) lockdowns have had diverse impacts on global aerosol concentrations. In 2022, Changchun, a provincial capital city in Northeast China, suffered a severe COVID-19 outbreak and implemented a very strict lockdown that lasted for nearly two months. Using ground-based polarization Light Detection and Ranging (LiDAR), we detected real-time aerosol profile parameters (EC, extinction coefficient; DR, depolarization ratio; AOD, aerosol optical depth), as well as air-quality and meteorological indexes from 1 March to 30 April in 2021 and 2022 to quantify the effects of lockdown on aerosol concentrations. The period in 2022 was divided into three stages: pre-lockdown (1-10 March), strict lockdown (11 March to 10 April), and partial lockdown (11-30 April). The results showed that, during the strict lockdown period, compared with the pre-lockdown period, there were substantial reductions in aerosol parameters (EC and AOD), and this was consistent with the concentrations of the atmospheric pollutants PM2.5 (particulate matter with an aerodynamic diameter ≤ 2.5 µm) and PM10 (particulate matter with an aerodynamic diameter ≤ 10 µm), and the O3 concentration increased by 8.3%. During the strict lockdown, the values of EC within 0-1 km and AOD decreased by 16.0% and 11.2%, respectively, as compared to the corresponding period in 2021. Lockdown reduced the conventional and organized emissions of air pollutants, and it clearly delayed the time of seasonal emissions from agricultural burning; however, it did not decrease the number of farmland fire points. Considering meteorological factors and eliminating the influence of wind-blown dust events, the results showed that reductions from conventional organized emission sources during the strict lockdown contributed to a 30% air-quality improvement and a 22% reduction in near-surface extinction (0-2 km). Aerosols produced by urban epidemic prevention and disinfection can also be identified using the EC. Regarding seasonal sources of agricultural straw burning, the concentrated burning induced by the epidemic led to the occurrence of heavy pollution from increased amounts of atmospheric aerosols, with a contribution rate of 62%. These results indicate that there is great potential to further improve air quality in the local area, and suggest that the comprehensive use of straw accompanied by reasonable planned burning is the best way to achieve this.
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BACKGROUND: To compare changes in the composition of paraspinal muscles of patients with ankylosing spondylitis (AS) and matched healthy controls using T2 mapping and T2 IDEAL and correlate the quantitative magnetic resonance imaging (qMRI) results with clinical assessments of AS patients. METHOD: In total, 37 AS patients and 37 healthy controls were enrolled in the case control study. T2 mapping with and without fat saturation and IDEAL imaging were used to assess the multifidus (MF) and erector spinae (ES) at the levels of L3/L4 and L4/L5 for all subjects. Mean T2non-fatsat, T2fat, T2fatsat, cross-sectional area (CSA), and fat fraction (FF) were compared between AS and healthy controls. Correlations of qMRI results with clinical assessments were analyzed in AS. RESULTS: Significantly elevated mean T2non-fatsat values and the FF of the MF and ES at both levels were observed in AS and compared to the controls (p < 0.05). The mean T2fatsat values of ES and MF were significantly higher only at the level of L3/L4 in AS compared to healthy controls (p < 0.05). A loss of muscle CSA compatible with atrophy was present in MF and ES at both levels in AS compared to the controls (p < 0.05). Weak to moderate positive correlations were found between FF and age and disease duration in AS (r = 0.318-0.415, p < 0.05). However, such positive correlation was not observed between FF and disease duration after adjusting for age (p > 0.05). CONCLUSIONS: Our findings indicate that using a combination of IDEAL and T2 mapping may provide deeper insights into the pathophysiological degeneration of paraspinal muscles in AS.
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Músculos Paraespinais , Espondilite Anquilosante , Estudos de Casos e Controles , Humanos , Vértebras Lombares , Região Lombossacral , Imageamento por Ressonância Magnética , Músculos Paraespinais/diagnóstico por imagem , Espondilite Anquilosante/diagnóstico por imagemRESUMO
Optic neuritis (ON) is a general term for inflammation of any part of the optic nerve resulting from demyelination or infection. The number of patients with MOG-lgG antibody-related optic neuritis is increasing recently. Our study uses the fractional amplitude of low-frequency fluctuation (fALFF) method to compare the activity of specific brain regions in MOG-lgG ON patients and healthy controls (HCs). We selected a total of 21 MOG-lgG ON patients and 21 HCs were included in the study. All subjects underwent resting-state functional magnetic resonance imaging (rs-fMRI). The independent-samples t-test was used to compare demographic data and average fALFF values between groups. The specificity and sensitivity of fALFF values for distinguishing between MOG-lgG ON patients and HCs were evaluated by receiver operating characteristic (ROC) curve analysis. Pearson's correlation analysis was used to analyze the relationship between fALFF values and clinical characteristics in MOG-lgG ON patients. Our results showed that fALFF values of the right cerebellum and left middle cingulum were lower whereas those of bilateral inferior temporal lobes, right gyrus rectus, and the left superior and right middle frontal lobes of MOG-lgG ON patients were higher than those of HCs (P < 0.05). The average fALFF value of the left superior frontal lobe in MOG-lgG ON patients was positively correlated with Hospital Anxiety and Depression Scale score (HADS) (r = 0.6004; P < 0.05) and duration of MOG-lgG ON (r = 6487; P < 0.05). Thus, patients with MOG-lgG ON have abnormal activity in the brain regions related to vision. Changes in fALFF value can reflect functional sequelae of MOG-lgG ON, including abnormal anxiety or depressive emotional changes.
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Imageamento por Ressonância Magnética , Neurite Óptica , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Lobo Frontal , Humanos , Imageamento por Ressonância Magnética/métodos , Neurite Óptica/diagnóstico por imagem , Neurite Óptica/patologia , Lobo TemporalRESUMO
The proportion of individuals with depression has rapidly increased along with the growth of the global population. Depression has been the currently most prevalent mental health disorder. An effective depression recognition system is especially crucial for the early detection of potential depression risk. A depression-related dataset is also critical while evaluating the system for depression or potential depression risk detection. Due to the sensitive nature of clinical data, availability and scale of such datasets are scarce. To our knowledge, there are few extensively practical depression datasets for the Chinese population. In this study, we first create a large-scale dataset by asking subjects to perform five mood-elicitation tasks. After each task, subjects' audio and video are collected, including 3D information (depth information) of facial expressions via a Kinect. The constructed dataset is from a real environment, i.e., several psychiatric hospitals, and has a specific scale. Then we propose a novel approach for potential depression risk recognition based on two kinds of different deep belief network (DBN) models. One model extracts 2D appearance features from facial images collected by an optical camera, while the other model extracts 3D dynamic features from 3D facial points collected by a Kinect. The final decision result comes from the combination of the two models. Finally, we evaluate all proposed deep models on our built dataset. The experimental results demonstrate that (1) our proposed method is able to identify patients with potential depression risk; (2) the recognition performance of combined 2D and 3D features model outperforms using either 2D or 3D features model only; (3) the performance of depression recognition is higher in the positive and negative emotional stimulus, and females' recognition rate is generally higher than that for males. Meanwhile, we compare the performance with other methods on the same dataset. The experimental results show that our integrated 2D and 3D features DBN is more reasonable and universal than other methods, and the experimental paradigm designed for depression is reasonable and practical.
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Cellulosomes are highly efficient multienzyme complexes for lignocellulose degradation secreted by some lignocellulolytic bacteria. Cellulosomes are assembled through protein modules named cohesin and dockerin, and multiple cohesin modules in the scaffold protein generally determine the complexity of the cellulosomes. Some cellulosomal proteins contain multiple dockerin modules, which may generate more complex cellulosomal architectures. Genome mining revealed that cellulosomal proteins containing double dockerin modules and a protease module exist in many cellulosome-producing bacteria, and these proteins together with cellulosomal protease inhibitors were proposed to have regulatory roles. However, the structures and functions of these multiple-dockerin proteins in cellulosome have not been reported before. In this paper, we present the NMR chemical shift assignments of the double-dockerin of a cellulosomal protease from Clostridium thermocellum DSM1313. The secondary structures predicted from the chemical shifts agree with the structural arrangement of the tandem dockerin modules. The chemical shift assignments here provide the basis for the structural and functional studies of multiple-dockerin proteins in future.
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Proteínas de Bactérias/química , Celulossomas/química , Clostridium thermocellum/química , Ressonância Magnética Nuclear Biomolecular , Isótopos de Nitrogênio , Estrutura Secundária de Proteína , PrótonsRESUMO
The soil microbial communities play an important role in plant health, however, the relationship between the below-ground microbiome and above-ground plant health remains unclear. To reveal such a relationship, we analyzed soil microbial communities through sequencing of 16S rRNA gene amplicons from 15 different tobacco fields with different levels of wilt disease in the central south part of China. We found that plant health was related to the soil microbial diversity as plants may benefit from the diverse microbial communities. Also, those 15 fields were grouped into 'healthy' and 'infected' samples based upon soil microbial community composition analyses such as unweighted paired-group method with arithmetic means (UPGMA) and principle component analysis, and furthermore, molecular ecological network analysis indicated that some potential plant-beneficial microbial groups, e.g., Bacillus and Actinobacteria could act as network key taxa, thus reducing the chance of plant soil-borne pathogen invasion. In addition, we propose that a more complex soil ecology network may help suppress tobacco wilt, which was also consistent with highly diversity and composition with plant-beneficial microbial groups. This study provides new insights into our understanding the relationship between the soil microbiome and plant health.
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We present a bilayer fractal structure for the realization of multiband left-handed metamaterial at terahertz frequencies. The structure is composed of metallic H-fractal pairs separated by a dielectric layer. The electromagnetic properties of periodic H-fractal pairs have been investigated by numerical simulation. The period in the propagation direction is extremely small as compared to the wavelength at the operational frequency. Under the electromagnetic wave normal incidence, the material exhibits negative refraction simultaneously around the frequencies of 0.10 and 0.15 THz for parallel polarization, and around the frequencies of 0.19 and 0.38 THz for perpendicular polarization. The design provides a left-handed metamaterial suitable for multiband and compact devices at terahertz frequencies.
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OBJECTIVE: To understand the self-discrimination experience of MSM and its relationship with sexual behavior and psychological factors. METHODS: By respondent-driven sampling (RDS) method, a call-for action and anonymous self-administration questionnaire investigation was carried out in Mianyang city on experience of self-discriminations, sexual partners and behaviors and depression symptom, etc. The first 12 qualified people were designated as the "root" in the whole investigation from different MSM subgroups. Every "root" would get 3 recruit cards after their own investigation, then cards could be promoted to another 3 qualified people who were willing to accept questionnaires. And this process would go on till the sample size was accomplished. χ(2) test, rank correlation and contingency coefficient would be applied for the statistical analysis. RESULTS: In total, 201 persons were investigated. Within the past 6 months, 59.2% (119/201) persons felt they did harm to their family or made the family down as gays, 79.6% (160/201) had to disguise their real sexual orientation in avoidance of being discriminated, 39.3% (79/201) were humiliated for having gay sex. It showed correlation between humiliation or harm to family and frequency to disco balls/night clubs (r = 0.196, χ(2) = 7.95, P < 0.05), concerts or theaters (r = 0.201, χ(2) = 8.423, P < 0.05) with MSM friends, HIV health consultancy (r = 0.231, χ(2) = 11.329, P < 0.05), experiences of one night stands (r(s) = 0.183, µ = 2.588, P < 0.05), detection of depression (r(s) = 0.241, µ = 15.717, P < 0.05) and stress-related perception (r(s) = -0.310, µ = 23.112, P < 0.05), the corresponding behavior report rates of who experienced 3-4 times were 66.7% (11/33), 52.9% (18/34), 41.2% (14/34), 17.6% (6/34), 44.1% (15/34), 44.7% (10/24). Statistical significance was found between the relations of humiliation for gay sex and frequency into concerts or theaters (r = 0.195, χ(2) = 7.933, P < 0.05) with MSM friends, experiences of one night stands (r(s) = 0.145, µ = 2.051, P < 0.05), man-man anal sex (r = 0.165, χ(2) = 10.823, P < 0.05), numbers of female sexual partners (r = 0.265, χ(2) = 11.422, P < 0.05), protectiveness of female sexual behavior in the past 6 months (r = 0.513, χ(2) = 7.442, P < 0.05), detection of depression (r(s) = 0.152, µ = 13.034, P < 0.05) and stress-related perception (r(s) = -0.259, µ = 21.190, P < 0.05), the corresponding behavior report rates of who experienced 3-4 times were 22.7% (5/22), 9.1% (2/22), 13.6% (3/22), 91.6% (2/22), 66.7% (2/3), 57.1% (4/7), 33.3% (19/57). It has statistical significance between the relations of disguising their real sexual orientation in avoidance of being discriminated and the frequency of show up in the cybercafé (r = 0.272, χ(2) = 15.932, P < 0.05), involvement of HIV test (r = 0.232, χ(2) = 11.446, P < 0.05), and stress-related perception (r(s) = -0.373, µ = 28.868, P < 0.05). It was found that increasing of discrimination was connected to entrance into gay-welcome places, acceptance of HIV consultancy and tests, posting gay information among MSM friends and hold of many sexual partners. Meanwhile, the pressure was rising when depression was checked out. CONCLUSION: Self-discrimination was prevalent among MSM, which had brought critical influence on the individual behavior, MSM psychological health and prevalence of AIDS.
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Homossexualidade Masculina/psicologia , Preconceito , Comportamento Sexual , Adolescente , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Autoimagem , Controles Informais da Sociedade , Inquéritos e Questionários , Adulto JovemRESUMO
AIMS: To determine the prevalence and biochemical/hormonal determinants of osteopenia/osteoporosis in postmenopausal Chinese women with type 2 diabetes. METHODS: This cross-sectional study was carried out in 890 postmenopausal women with type 2 diabetes and 689 age-matched non-diabetic women. Of the total subjects included in both groups were classified as obese (BMI ≥ 25 kg/m²) and non-obese (BMI< 25 kg/m²). Bone mineral density (BMD) at the sites (lumbar spine, femoral neck, and hip), obtained by dual X-ray absorptiometry and some other relevant clinical and laboratory indices of bone mineral metabolism were investigated. The prevalence of osteopenia and that of osteoporosis were evaluated. RESULTS: BMDs, T- and Z-scores at the total hip, femoral neck and ward's triangle were significantly lower in non-obese diabetic women than those in BMI-matched control subjects (P < 0.038). Obese diabetic patients and control subjects had similar BMDs and T- and Z-scores at various skeletal regions. Osteopenia/osteoporosis was more common at the hip and femoral neck in non-obese diabetic women than in obese diabetic women and control subjects (P = 0.026). On multiple linear regression analysis, which was adjusted for the sex hormone concentration, BMI, fasting insulin level, and serum osteocalcin were positively associated with BMDs at the hip and lumbar spine. Age, mean HbA1(c) levels, and NTx/Cr showed negative correlation (P < 0.0284) with BMD at the lumbar spine and femoral neck. CONCLUSIONS: Postmenopausal non-obese women with type 2 diabetes have lower BMD levels and higher osteopenia/osteoporosis rate than BMI-matched control subjects. Impaired bone formation may occur in Chinese postmenopausal women with type 2 diabetes.
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Doenças Ósseas Metabólicas/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Osteoporose Pós-Menopausa/epidemiologia , Absorciometria de Fóton , Idoso , Povo Asiático , Densidade Óssea , Doenças Ósseas Metabólicas/complicações , China/epidemiologia , Estudos Transversais , Feminino , Quadril/diagnóstico por imagem , Humanos , Insulina/sangue , Vértebras Lombares/diagnóstico por imagem , Pessoa de Meia-Idade , Obesidade/complicações , Osteocalcina/sangue , Osteoporose Pós-Menopausa/complicações , PrevalênciaRESUMO
AIMS: Advanced glycation end products (AGEs) trigger an oxidative reaction which then accelerates endothelial cell apoptosis; this is a critical event in the process of diabetic vascular complications. We previously demonstrated that hepatocyte growth factor (HGF) protects human endothelial cells against AGE-induced injury. The present study was designed to investigate the possible involvement of MAPK and PI3K/Akt signaling in the action of HGF. MAIN METHODS: HUVECs were treated with AGEs in the presence or absence of HGF. For detection of apoptosis, the morphological Acridine Orange staining, flow cytometry, and caspase-3 activity assay were used. Generation of reactive oxygen species (ROS) and the change in mitochondrial membrane potential were measured using flow cytometry and fluorescence immune analysis. The activation of MAPK and Akt was assayed by Western blot. KEY FINDINGS: HGF exerted its prosurvival effect by inhibiting the overproduction of intracellular ROS and the depolarization of mitochondrial membrane, induced by AGEs. HGF-induced survival correlated with Akt activity and was inhibited by the specific PI3K inhibitor. ERK also was activated by HGF and rescued cells from apoptosis, although the cytoprotective effect was less marked than for PI3K/Akt. HGF-mediated survival was independent of JNK and p38MAPK pathways. Furthermore, blocking the PI3K and Akt activities with PI3K inhibitors or transfection of HUVECs with the dominant-negative p85 or Akt effectively abolished the inhibition of the intracellular ROS production and mitochondrial damage. SIGNIFICANCE: Our studies suggest that HGF, via PI3K/Akt signaling, prevents AGE-induced apoptosis and oxidative stress through the inhibition of mitochondrial damage in HUVECs.
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Células Endoteliais/efeitos dos fármacos , Produtos Finais de Glicação Avançada/antagonistas & inibidores , Produtos Finais de Glicação Avançada/toxicidade , Fator de Crescimento de Hepatócito/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Transdução de Sinais/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Western Blotting , Caspase 3/metabolismo , Humanos , Potenciais da Membrana/efeitos dos fármacos , Fosforilação , Espécies Reativas de OxigênioRESUMO
OBJECTIVE: To determine feasibility and effectiveness of the intervention on HIV/AIDS among MSM based on venues and peer network. METHODS: The intervention trial was conducted in Mianyang and Yibin in Sichuan province, where the cultural and social environment were similar. These two cities have no HIV/AIDS intervention conducted yet before this study. The intervention was conducted in Mianyang, while Yibin was regarded as control, in which education materials related HIV/AIDS and VCT service were available. Intervention in Mianyang included MSM venue intervention distributing the education materials, condom and promoting HIV-test and STIs clinic referral by 40 MSM as Popular Opinion Leaders who received the knowledge and intervention skill training.Meanwhile, Popular Opinion Leader intervention was implemented in MSM peer network to advocate safe sex. After 6-month intervention the survey was conducted to assess the effectiveness of intervention. RESULTS: The scores of knowledge related HIV/STDs and self-efficacy of condom use was 1.293 (95%CI: 0.657 - 1.292, P < 0.05) and 1.556 (95%CI: 0.656 - 2.456, P < 0.05) higher in post-intervention than in pre-intervention which was (12.42 +/- 0.232) and (10.25 +/- 0.327) respectively in Mianyang, while no significant changing in Yibin during the time. Score of knowledge related HIV/STDs increase 0.577 (95%CI: -0.173 - 1.327, P > 0.05) in post-intervention compared with (10.40 +/- 0.412) in pre-intervention and score of self-efficacy of condom use decreased 0.362 from 9.86 +/- 0.547 in pre-intervention (95%CI: -1.458 - 0.534, P > 0.05). In the six months prior to survey, the rate of unprotected sexual intercourse with male casual sexual partners in last 3 times decreased to 11.0% (22/200) (OR(adjusted) = 0.472, 95%CI: 0.265 - 0.841, P < 0.05) from 19.5% (39/200) baseline in Manyang, while in Yibin that increased to 19.0% (38/200) from 17.5% (35/200) in baseline (OR(adjusted) = 1.153, 95%CI: 0.660 - 2.014, P > 0.05). The rate of HIV-test increased significantly from 9.0% (18/200) to 22.0% (44/200) (OR = 2.852, 95%CI: 1.583 - 5.138, P < 0.05) in intervention city and Accordingly in the control, that was 24.5% (29/200) in baseline and 24.0% (28/200) in post-intervention (OR = 0.960, 95%CI: 0.548 - 1.682, P > 0.05). No difference was found in number of male sexual partner pre- and post-intervention both in intervention and control city. CONCLUSION: The intervention based on MSM venues and peer network among MSM is feasible and can increase knowledge related HIV/STDs and self-efficacy and as well as condom use and HIV testing.