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1.
Molecules ; 28(24)2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38138439

RESUMO

Carbon dioxide flooding is one of the main methods used to improve crude oil recovery. It can not only improve oil recovery but also reduce greenhouse gas emissions. However, the addition of carbon dioxide makes crude oil become a more complex multiphase fluid; that is, carbon dioxide flooding-produced fluid, in which CO2 and various components in crude oil mass transfer each other. This results in significant changes in the structure and properties of crude oil that increase the hazards associated with its gathering and transportation. Therefore, it is very important to explore the microscopic mechanism for the diffusion mass transfer of CO2 and crude oil in this fluid, especially during its gathering and transportation. In this study, the diffusion mass transfer process of CO2 and crude oil in fluids produced via CO2 flooding is studied using molecular dynamics, and the influences of temperature, gas-oil ratio and water content are explored. Observations of the configuration and dynamic behaviour of the system show that after the system reaches equilibrium, the majority of the CO2 molecules are distributed at the oil-water interface, and CO2 is more prone to diffusing into the oil phase than the water phase. Increases in temperature and water content inhibit, while increases in the gas-oil ratio promote, the diffusion mass transfer of CO2 in the crude oil system. The results of this study reveal the mechanism for the diffusion mass transfer of CO2 and crude oil in fluids produced via CO2 flooding and account for the influence of the water phase, which is consistent with actual production conditions and has certain guiding significance for the safe operation of oil and gas gathering and transportation.

2.
J Med Virol ; 94(4): 1617-1626, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34882805

RESUMO

This study aimed to assess the efficacy and safety of different medications available at present for severe coronavirus disease 2019 (COVID-19) infection. We searched databases for randomized controlled trials (RCTs) published up to April 30, 2021, with Chinese or English language restriction, of medications recommended for patients (aged 18 years or older) with severe COVID-19 infection. We extracted data on trials and patient characteristics, and the following primary outcomes: all-cause mortality (ACM), and treatment-emergent adverse events (TEAEs). We identified 1855 abstracts and of these included 15 RCTs comprising 3073 participants through database searches and other sources. In terms of efficacy, compared with the standard of care (SOC) group, no significant decrease in ACM was found in α-lipoic acid, convalescent plasma (CP), azithromycin, tocilizumab, methylprednisolone, interferon beta, CP/SOC, high dosage sarilumab, low dosage sarilumab, remdesivir, lopinavir-ritonavir, auxora, and placebo group. Compared with placebo, we found that a significant decrease in ACM was only found in methylprednisolone (odds ratio [OR]: 0.16, 95% confidence interval [CI]: 0.03-0.75]. With respect to TEAEs, the CP group showed lower TEAEs than placebo (OR: 0.07, 95% CI: 0.01-0.58) or SOC (OR: 0.05, 95% CI: 0.01-0.42) group for the therapy of severe COVID-19 patients. This study only demonstrated that methylprednisolone was superior to placebo in treating patients with severe COVID-19 infection. Meanwhile, this further confirmed that the safety of other treatment interventions might be inferior to CP for the therapy of severe COVID-19 patients.


Assuntos
COVID-19/terapia , Metanálise em Rede , COVID-19/mortalidade , Humanos , SARS-CoV-2 , Índice de Gravidade de Doença , Resultado do Tratamento
3.
Molecules ; 27(14)2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35889304

RESUMO

To explore the influence of different wax components and the shear effect exerted by the pump and pipe wall in the process of crude oil pipeline transportation on the microbehavior of wax aggregation in crude oil at low temperatures, molecular dynamics models of binary and multivariate systems of crude oil with different wax components are established in this paper. The simulation results are compared with the existing experimental results and the NIST database to verify the rationality and accuracy of the models. By using the established binary model to simulate four crude oil systems containing different wax components, it can be found that the longer the wax molecular chain, the more easily the wax molecules aggregate. The influence of temperature on the aggregation process of wax molecules with different chain lengths is also studied. The lower the temperature, the greater the difference in wax molecular aggregation degree caused by the difference in molecular chain length. Nonequilibrium molecular dynamics is used to simulate the shear process of a multivariate system of crude oil, and the micromechanisms of the shear effect on the aggregation process of wax molecules are studied. Shearing can destroy the stable structure of crude oil, resulting in the orientation and conformational transformation of wax molecules, and obtaining the region of wax molecules sensitive to temperature and shear effects, the temperatures of which are below the wax precipitation point and the shear rate of which is lower than the maximum shear rate to prevent the molecular structure from being destroyed. At the same time, the sensitivity of wax components with different chain lengths to the shear effect is studied. The research results provide theoretical guidance for ensuring the safe and economic operation of waxy crude oil production.

4.
Entropy (Basel) ; 21(1)2019 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33266774

RESUMO

Based on the technological requirements related to waxy crude oil pipeline transportation, both unavoidable and avoidable destroyed exergy are defined. Considering the changing characteristics of flow pattern and flow regime over the course of the oil transportation process, a method of dividing station oil pipelines into transportation intervals is suggested according to characteristic temperatures, such as the wax precipitation point and abnormal point. The critical transition temperature and the specific heat capacity of waxy crude oil are calculated, and an unavoidable destroyed exergy formula is derived. Then, taking the Daqing oil pipeline as an example, unavoidable destroyed exergy in various transportation intervals are calculated during the actual processes. Furthermore, the influential rules under various design and operation parameters are further analyzed. The maximum and minimum unavoidable destroyed exergy are 381.128 kJ/s and 30.259 kJ/s. When the design parameters are simulated, and the maximum unavoidable destroyed exergy is 625 kJ/s at the diameter about 250 mm. With the increase of insulation layer thickness, the unavoidable destroyed exergy decreases continuously, and the minimum unavoidable destroyed exergy is 22 kJ/s at 30 mm. And the burial depth has little effect on the unavoidable destroyed exergy. When the operation parameters are simulated, the destroyed exergy increases, but it is less affected by the outlet pressure. The increase amplitude of unavoidable destroyed exergy will not exceed 2% after the throughput rises to 80 m3/h. When the outlet temperature increases until 65 °C, the loss increase range will not exceed 4%. Thus, this study provides a theoretical basis for the safe and economical transportation of waxy crude oil.

5.
Environ Health Prev Med ; 23(1): 5, 2018 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-29415649

RESUMO

BACKGROUND: Few studies have attempted to compare the differences in the prevalence and impact factors of hysterical tendencies (HTs) in adolescents. Thus, the aim of this study was to examine gender differences in the prevalence and impact factors of adolescents' HTs across three eastern Chinese provinces (Anhui, Jiangsu, and Zhejiang). METHODS: A multicenter, school-based, cross-sectional study was conducted in three provinces (Anhui, Jiangsu, and Zhejiang) in China in 2014. The sample included 10,131 middle-school students aged 13-18 years who were randomly selected using a multiphase, stratified, cluster sampling technique. A two-stage appraisal procedure was used to determine the adolescents' HTs. We also designed a multicenter, school-based, case control (1329 cases with 2661 control individuals) study to collect data on the common factors affecting this population using a common protocol and questionnaire. RESULTS: An overall positive rate of HTs among adolescents across the three eastern Chinese provinces studied was found at 13.1% (95% confidence interval (CI) 12.5-13.8%), at 14.5% (95% CI 13.3-15.7%) for females, and at 12.2% (95% CI 11.1-13.4%) for males. Gender-stratified, multiple conditional regression analyses revealed that superstitious beliefs pertaining to life, somatotype, teacher-student satisfaction, and family achievement orientation were significantly linked to HTs only in males, while left-behind adolescents, emotional and social adaptation, teacher-student support, family cohesion, and the Hospital Anxiety and Depression Scale - depression scores were significantly associated with female HTs only. The models indicated that of all the independent variables studied, family medical history was the strongest impact factor for both male HTs (adjusted matched odds ratio (amOR) = 2.92, 95% CI = 1.84-4.86) and female HTs (amOR = 2.74, 95% CI = 1.59-4.98). CONCLUSIONS: HTs are prevalent among adolescents in the three eastern Chinese provinces studied. Gender differences in the prevalence and impact factors of HTs are significant in adolescents, and HTs seem to affect more females than males. Therefore, sex-specific intervention programs against HTs in adolescents should be considered to reduce HT prevalence in adolescents by modifying influential social, school, and family factors.


Assuntos
Comportamento do Adolescente/psicologia , Transtorno da Personalidade Histriônica/epidemiologia , Adolescente , China/epidemiologia , Estudos Transversais , Feminino , Transtorno da Personalidade Histriônica/psicologia , Humanos , Masculino , Prevalência , Fatores de Risco , Fatores Sexuais , Estudantes/psicologia
6.
Entropy (Basel) ; 20(5)2018 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-33265400

RESUMO

With the increasing demand of oil products in China, the energy consumption of pipeline operation will continue to rise greatly, as well as the cost of oil transportation. In the field of practical engineering, saving energy, reducing energy consumption and adapting to the international oil situation are the development trends and represent difficult problems. Based on the basic principle of non-equilibrium thermodynamics, this paper derives the field equilibrium equations of non-equilibrium thermodynamic process for pipeline transportation. To seek the bilinear form of "force" and "flow" in the non-equilibrium thermodynamics of entropy generation rate, the oil pipeline exergy balance equation and the exergy transfer pipeline dynamic equation of the irreversibility were established. The exergy balance equation was applied to energy balance evaluation system, which makes the system more perfect. The exergy flow transfer law of the waxy oil pipeline were explored deeply from the directions of dynamic exergy, pressure exergy, thermal exergy and diffusion exergy. Taking an oil pipeline as an example, the influence factors of exergy transfer coefficient and exergy flow density were analyzed separately.

7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(3): 698-703, 2014 Mar.
Artigo em Zh | MEDLINE | ID: mdl-25208395

RESUMO

The water samples of the Tien Lake were collected for the three-dimensional fluorescence spectrum detected. And parallel factor analysis (PARAFAC) and principal component analysis (PCA) were used for the spectra analyzing to know the main factor and relative contribution of the chromophoric dissolved organic matter (CDOM). PARAFAC decomposed CDOM into four components, the humic-like: C1 (240, 415), C3 (265, 525), C4 (255, 505) and the protein-like: C2(230/280, 330). The fluorescence intensity of CDOM components was high in north and estuary of the lake, but low in the other region. All the four components show significant positive correlations (p < 0.01), this result means they may have the same sources. Principal component analysis shows that these four components of the Tien Lake are all from terrestrial organic matter, meanwhile its DTN, DTP, DON may also come with the terrestrial substance. These components of Tien Lake can well be connected with dissolved nutrient salts by nonlinear multiple regression, which means we can use the three-dimensional fluorescence spectrum results of CDOM to indicate the eutrophication degree of Tien Lake.


Assuntos
Monitoramento Ambiental , Eutrofização , Lagos/química , Compostos Orgânicos/análise , Análise Fatorial , Análise de Componente Principal , Espectrometria de Fluorescência
8.
Water Res ; 236: 119937, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37054612

RESUMO

Long-term anthropogenic nitrogen (N) and phosphorus (P) inputs have led to lake eutrophication and decreased environmental quality. However, the imbalance in nutrient cycling caused by ecosystem transformation during lake eutrophication is still unclear. The N, P, organic matter (OM) and their extractable forms in the sediment core of Dianchi Lake were investigated. Combining ecological data and geochronological techniques, a coupling relationship between the evolution of lake ecosystems and nutrient retention was established. The results show that the evolution of lake ecosystems promotes the accumulation and mobilization of N and P in sediments, leading to an imbalance in nutrient cycling in the lake system. From the "macrophyte-dominated" period to the "algae-dominated" period, the accumulation rates of potential mobile N and P (PMN, PMP) in sediments have significantly increased, and the retention efficiency of total N and P (TN, TP) has decreased. The increased TN/TP ratio (5.38 ± 1.52 ‒ 10.19 ± 2.94) and PMN/PMP ratio (4.34 ± 0.41 ‒ 8.85 ± 4.16), as well as the reduced humic-like/protein-like ratio (H/P, 11.18 ± 4.43 ‒ 5.97 ± 3.67), indicated an imbalance in nutrient retention during sedimentary diagenesis. Our results show that eutrophication has resulted in the potential mobilization of N in sediments exceeding P, providing new insights for further understanding the nutrient cycle in the lake system and strengthening lake management.


Assuntos
Monitoramento Ambiental , Lagos , Monitoramento Ambiental/métodos , Ecossistema , Sedimentos Geológicos , Eutrofização , Nutrientes , Fósforo/análise , Nitrogênio/análise , China
9.
Clin Exp Med ; 23(4): 1307-1316, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36168074

RESUMO

The relationship between plasma EBV-DNA load (PEDL) and Epstein-Barr virus (EBV)-encoded small RNA (EBER) during the early treatment of lymphoma remains unclear. We explored discrepancies in PEDL and variables associated with EBER and evaluated the consistency between EBER and qualitative analysis of PEDL (qPEDL). Serial measurements of PEDL were performed to determine the dynamic changes of PEDL in early treatment of lymphoma. As a result, the median PEDL of non-Hodgkin's lymphoma NKT cell subtype (NHL-NKT) was higher than that of non-Hodgkin's lymphoma B cell subtype (NHL-B), the median PEDL of extranodal NK/T cell lymphoma (ENKTCL) was higher than that of diffuse large B cell lymphoma (DLBCL), and the median PEDL of EBER positive was higher than that of EBER negative. Age, Ki-67 ≧ 80%, Bcl-2 ≧ 80%, p53, and qPEDL were related to EBER. The PEDL could distinguish NHL-B, DLBCL, NHL-NKT, and ENKTCL from other lymphoma subtypes. EBER-positive patients spent more time with viral "turn negative (TN)" and "continuous positive (CP)" and less time with viral "continuous negative (CN)." The median PEDL of CP was higher than that of TN. In conclusion, although EBER affects the levels of PEDL in general, it has poor concordance with qPEDL. Our results show, for the first time, that high PEDL and positive EBER present a strong association with viral recurrence and persistent infection in the early treatment of lymphoma.


Assuntos
Infecções por Vírus Epstein-Barr , Linfoma Extranodal de Células T-NK , Linfoma Difuso de Grandes Células B , Humanos , Herpesvirus Humano 4/genética , Infecções por Vírus Epstein-Barr/complicações , Infecção Persistente , Linfoma Difuso de Grandes Células B/patologia , DNA Viral , RNA Viral
10.
Medicine (Baltimore) ; 101(41): e30998, 2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36254081

RESUMO

BACKGROUND: To date, there has been little agreement on what drug is the "best" drug for treating severe COVID-19 patients. This study aimed to assess the efficacy and safety of different medications available at present for severe COVID-19. METHODS: We searched databases for randomized controlled trials (RCTs) published up to February 28, 2022, with no language restrictions, of medications recommended for patients (aged 16 years or older) with severe COVID-19 infection. We extracted data on trials and patient characteristics, and the following primary outcomes: all-cause mortality (ACM), and treatment-emergent adverse events (TEAEs). RESULTS: We identified 4021 abstracts and of these included 48 RCTs comprising 9147 participants through database searches and other sources. For decrease in ACM, we found that ivermectin/doxycycline, C-IVIG (i.e., a hyperimmune anti-COVID-19 intravenous immunoglobulin), methylprednisolone, interferon-beta/standard-of-care (SOC), interferon-beta-1b, convalescent plasma, remdesivir, lopinavir/ritonavir, immunoglobulin gamma, high dosage sarilumab (HS), auxora, and imatinib were effective when compared with placebo or SOC group. We found that colchicine and interferon-beta/SOC were only associated with the TEAEs of severe COVID-19 patients. CONCLUSION: This study suggested that ivermectin/doxycycline, C-IVIG, methylprednisolone, interferon-beta/SOC, interferon-beta-1b, convalescent plasma (CP), remdesivir, lopinavir/ritonavir, immunoglobulin gamma, HS, auxora, and imatinib were efficacious for treating severe COVID-19 patients. We found that most medications were safe in treating severe COVID-19. More large-scale RCTs are still needed to confirm the results of this study.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19 , Infecções por Coronavirus , Pneumonia Viral , COVID-19/terapia , Colchicina/uso terapêutico , Infecções por Coronavirus/terapia , Doxiciclina/uso terapêutico , Humanos , Mesilato de Imatinib/uso terapêutico , Imunização Passiva , Imunoglobulinas Intravenosas/uso terapêutico , Interferon beta-1b/uso terapêutico , Ivermectina/efeitos adversos , Lopinavir/uso terapêutico , Metilprednisolona/uso terapêutico , Metanálise em Rede , Pandemias , Pneumonia Viral/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Ritonavir/uso terapêutico , Soroterapia para COVID-19
11.
Sci Rep ; 12(1): 20193, 2022 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-36418430

RESUMO

The purpose of this study was to explore the differences between the prevalence and impact factors of adolescent dissociative symptoms (ADSs) by using sex-stratification during the coronavirus disease 2019 (COVID-19) pandemic. A school-based, two-center cross-sectional study was conducted in Hangzhou City, China, between January 1, 2021 and April 30, 2022. The sample included 1,916 adolescents aged 13-18 years that were randomly selected using a multiphase, stratified, cluster sampling technique. A two-stage assessment procedure was used to find out the ADSs. We used a multivariate logistic regression analysis to assess the impact factors of ADSs during the COVID-19 pandemic. The adolescent dissociative scores (t = 4.88, P < 0.001) and positive ADSs rate (Chi-square = 15.76, P < 0.001) in males were higher than in females. Gender-stratified, stepwise multiple logistic regression analysis revealed that the conflict relationship of teacher-student [adjusted odds ratio (AOR) 1.06, 95% confidence interval (CI) 1.01-1.10], family expressiveness (AOR 0.87, 95% CI 0.78-0.98), family conflict (AOR 1.15, 95% CI 1.05-1.27), family organization (AOR 0.88, 95% CI 0.78-0.99), and family cohesion (AOR 0.87, 95% CI 0.77-0.99) were linked to ADSs only in males, while individual psychological states of somatic complaint (AOR 1.04, 95% CI 1.00-1.08) and paranoid ideation (AOR 1.09, 95% CI 1.01-1.19) were associated with female ADSs only. The ADSs seemed to be prevalent in Hangzhou City, studied during the COVID-19 pandemic. Gender differences in the prevalence and impact factors of dissociative symptoms seem to be significant among adolescents. Thus, gender-specific intervention programs against ADSs should be considered as reducing this risk.


Assuntos
COVID-19 , Pandemias , Masculino , Adolescente , Feminino , Humanos , COVID-19/epidemiologia , Prevalência , Estudos Transversais , Fatores Sexuais
12.
J Int Med Res ; 49(12): 3000605211039812, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34898296

RESUMO

OBJECTIVES: There are few systematic assessments of mass hysteria (MH) attack rates (ARs) in adolescents and children. The study aim was to assess the ARs of MH in this population. METHODS: We used a meta-analysis to systematically review studies and assess ARs. RESULTS: The reviewed studies included 32,887 participants, of which 2968 were children and adolescents with a history of MH. Twenty-eight studies were included, of which 22 (78.6%) had high to moderate methodological quality. The pooled AR of MH was 9.8% (95% confidence interval [CI] 6.3, 14.0). Of MH studies between 2010 and 2020, 78.6% were conducted between 2010 and 2014. ARs were higher between 2010 and 2014 (10.3%) than between 2015 and 2020 (8.1%). Regarding population characteristics, the AR in girls was 2.43 (95% CI 1.70, 3.46) times higher than in boys. Most studies were on primary school students (46.4%), who showed the highest AR (15.4%). Of six trigger factors, water pollution showed the highest AR (16.3%). ARs were higher in rural areas (11.1%) than in urban areas (5.6%). CONCLUSIONS: MH in children and adolescents seems prevalent and shows some epidemiological characteristics. These findings may assist governments to control and prevent MH epidemics among children and adolescents.


Assuntos
Histeria , Estudantes , Adolescente , Criança , Feminino , Humanos , Histeria/epidemiologia , Incidência , Masculino , Prevalência
13.
Aging (Albany NY) ; 13(18): 21866-21902, 2021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34531332

RESUMO

BACKGROUND: Many recent studies have investigated the role of drug interventions for coronavirus disease 2019 (COVID-19) infection. However, an important question has been raised about how to select the effective and secure medications for COVID-19 patients. The aim of this analysis was to assess the efficacy and safety of the various medications available for severe and non-severe COVID-19 patients based on randomized placebo-controlled trials (RPCTs). METHODS: We did an updated network meta-analysis. We searched the databases from inception until July 31, 2021, with no language restrictions. We included RPCTs comparing 49 medications and placebo in the treatment of severe and non-severe patients (aged 18 years or older) with COVID-19 infection. We extracted data on the trial and patient characteristics, and the following primary outcomes: all-cause mortality, the ratios of virological cure, and treatment-emergent adverse events. Odds ratio (OR) and their 95% confidence interval (CI) were used as effect estimates. RESULTS: From 3,869 publications, we included 61 articles related to 73 RPCTs (57 in non-severe COVID-19 patients and 16 in severe COVID-19 patients), comprising 20,680 patients. The mean sample size was 160 (interquartile range 96-393) in this study. The median duration of follow-up drugs intervention was 28 days (interquartile range 21-30). For increase in virological cure, we only found that proxalutamide (OR 9.16, 95% CI 3.15-18.30), ivermectin (OR 6.33, 95% CI 1.22-32.86), and low dosage bamlanivimab (OR 5.29, 95% CI 1.12-24.99) seemed to be associated with non-severe COVID-19 patients when compared with placebo, in which proxalutamide seemed to be better than low dosage bamlanivimab (OR 5.69, 95% CI 2.43-17.65). For decrease in all-cause mortality, we found that proxalutamide (OR 0.13, 95% CI 0.09-0.19), imatinib (OR 0.49, 95% CI 0.25-0.96), and baricitinib (OR 0.58, 95% CI 0.42-0.82) seemed to be associated with non-severe COVID-19 patients; however, we only found that immunoglobulin gamma (OR 0.27, 95% CI 0.08-0.89) was related to severe COVID-19 patients when compared with placebo. For change in treatment-emergent adverse events, we only found that sotrovimab (OR 0.21, 95% CI 0.13-0.34) was associated with non-severe COVID-19 patients; however, we did not find any medications that presented a statistical difference when compared with placebo among severe COVID-19 patients. CONCLUSION: We conclude that marked variations exist in the efficacy and safety of medications between severe and non-severe patients with COVID-19. It seems that monoclonal antibodies (e.g., low dosage bamlanivimab, baricitinib, imatinib, and sotrovimab) are a better choice for treating severe or non-severe COVID-19 patients. Clinical decisions to use preferentially medications should carefully consider the risk-benefit profile based on efficacy and safety of all active interventions in patients with COVID-19 at different levels of infection.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Tratamento Farmacológico da COVID-19 , Fatores Imunológicos/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Azetidinas/uso terapêutico , COVID-19/mortalidade , Humanos , Mesilato de Imatinib/uso terapêutico , Metanálise em Rede , Oxazóis/uso terapêutico , Purinas/uso terapêutico , Pirazóis/uso terapêutico , SARS-CoV-2 , Índice de Gravidade de Doença , Sulfonamidas/uso terapêutico , Tioidantoínas/uso terapêutico , Resultado do Tratamento
14.
J Glob Antimicrob Resist ; 24: 158-168, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33359935

RESUMO

OBJECTIVES: The impact of tuberculosis (TB) history on the risk of multidrug-resistant tuberculosis (MDR-TB) is not yet fully understood. We aimed to identify the impact of different TB history at the onset of future MDR-TB. METHODS: A large, retrospective, population-based cohort study was performed between 2005 and 2019. A multivariable Cox model was used to evaluate independent risk factors for MDR-TB for individuals with different previous TB history (PTBH), such as newly diagnosed TB history (NDTH) and re-treated TB history (RTH). RESULTS: Overall, 12 172 individuals with PTBH were included in this study. The main impacts of different PTBH at the onset of future MDR-TB were as follows: (a) low family income, high-risk occupation, TB patients with severe infection, extended or shortened treatment course, 2H3R3Z3E3/4H3R3 and frequency of sputum culture were significantly linked to incident MDR-TB only in individuals with NDTH (P < 0.05); (b) passive mode of TB case finding, individualised treatment regimens, 3HRZES/6HRE, duration of pulmonary cavities, excellent frequency of chest X-ray examination and duration of negative sputum smear were significantly associated with incident MDR-TB only in individuals with RTH (P < 0.05); (c) age <60 years, history of direct contact, human immunodeficiency virus (HIV) infection, unsuccessful treatment and duration of positive sputum culture were related to incident MDR-TB in both categories of PTBH individuals (P < 0.05). CONCLUSION: Early and differential surveillances, assessments and interventions for reducing the risk of MDR-TB among individuals with different PTBH play a key role.


Assuntos
Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose Pulmonar , Tuberculose , Antituberculosos/uso terapêutico , Estudos de Coortes , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Tuberculose/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Pulmonar/tratamento farmacológico
15.
Front Public Health ; 9: 644347, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34123987

RESUMO

Background: To date, too little attention has been paid to monitoring and estimating the risk of incident multidrug-resistant tuberculosis (MDR-TB) among individuals with a previous tuberculosis history (PTBH). The purpose of this study was to assess the incidence of and risk factors for MDR-TB in those individuals. Methods: Between 2005 and 2020, a large, retrospective, population-based cohort study was performed in Hangzhou, China. A multivariable Cox regression model was used to evaluate independent predictors of incident MDR-TB among individuals with PTBH. Results: The incidence density of MDR-TB was 22.6 per 1,000 person-years (95% confidence level and an interval of 20.9-24.3) for individuals with PTBH. The incidence of MDR-TB increased significantly in individuals who • were under 60 years old. • were male. • had a history of direct contact. • came from low-income families. • worked in high-risk occupations. • lived in rural areas. • had a retreatment TB history. • had an unfavorable outcome in their previous treatment (P < 0.05). In addition, we found that the following factors were significantly linked to the MDR-TB risk among individuals with PTBH (P < 0.05): • sociodemographic factors such as the 21-30 and 31-40 year age groups, or a history of direct contact. • clinical factors like passive modes of TB case finding (PMTCF), human immunodeficiency virus infection, unfavorable treatment outcomes, retreated TB history, non-standardized treatment regimens of retreatment TB patients, and duration of pulmonary cavities (DPC). • microbiological factors, such as duration of positive sputum culture. We also found that the 21-30 year age group, low family income, and PMTCF were significantly linked to incident MDR-TB only in males with PTBH, whilst the 41-50 year age group, extended treatment course, and DPC were significantly associated with female MDR-TB only. Conclusion: The incidence of MDR-TB was high, with a higher rate among subjects with a history of direct contact and unfavorable treatment outcomes. There was a gender difference in the incidence density and risk factors of MDR-TB among individuals with PTBH. Long-term monitoring and gender-specific risk-factor modifications should be given to individuals with PTBH.


Assuntos
Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , China/epidemiologia , Estudos de Coortes , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
16.
Risk Manag Healthc Policy ; 13: 255-269, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32256136

RESUMO

BACKGROUND: Until recently, almost all of these studies have identified multiple risk factors but did not offer practical instruments for routine use in predicting individualized survival in human H7N9 infection cases. The objective of this study is to create a practical instrument for use in predicting an individualized survival probability of H7N9 patients. METHODS: A matched case-control study (1:2 ratios) was performed in Zhejiang Province between 2013 and 2019. We reviewed specific factors and outcomes regarding patients with H7N9 virus infection (VI) to determine relationships and developed a nomogram to calculate individualized survival probability. This tool was used to predict each individual patient's probability of survival based on results obtained from the multivariable Cox proportional hazard regression analysis. RESULTS: We examined 227 patients with H7N9 VI enrolled in our study. Stepwise selection was applied to the data, which resulted in a final model with 8 independent predictors [including initial PaO2/FiO2 ratio ≤300 mmHg, age ≥60 years, chronic diseases, poor hand hygiene, time from illness onset to the first medical visit, incubation period ≤5 days, peak C-reactive protein ≥120 mg/L], and initial bilateral lung infection. The concordance index of this nomogram was 0.802 [95% confidence interval (CI): 0.694-0.901] and 0.793 (95% CI: 0.611-0.952) for the training and validation sets, respectively, which indicates adequate discriminatory power. The calibration curves for the survival showed optimal agreement between nomogram prediction and actual observation in the training and validation sets, respectively. CONCLUSION: We established and validated a novel nomogram that can accurately predict the survival probability of patients with H7N9 VI. This nomogram can serve an important role in counseling patients with H7N9 VI and guide treatment decisions.

17.
Sci Prog ; 103(1): 36850419881866, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31829896

RESUMO

The study of phase-change heat-transfer characteristics of crude oil has been one of the hot issues in the field of gathering and transportation. The process of phase-change heat transfer of crude oil involves many complicated problems such as natural convection treatment, latent heat treatment, phase-change interface determination and fluid characteristic change. A mathematical model based on the additional capacity heat method is proposed in this article, and the momentum equations of crude oil liquid phase are presented for Newtonian and non-Newtonian fluids. The aim of this study was to investigate the influence of different factors on the heat transfer performance during the shutdown process of an overhead pipe. Experiments were conducted to verify the model and the solution method; the experimental and model results showed good agreement with a maximum relative error of 4.57%. The temperature fields and solidification conditions of crude oil in pipelines under different shutdown conditions were determined, and the sensitivity of the main effect factors was determined through an orthogonal experiment. The results show that the order of influence was oil initial temperature >thickness of insulating layer >air temperature >thickness of wax layer. The results of the study have important guiding significance on the control of shutdown time and the determination of restarting schemes.

18.
Sci Rep ; 10(1): 13730, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792606

RESUMO

The purposes of this study were to construct a comprehensive nomogram for providing a simple, precise and personalized prediction of incident multidrug-resistant tuberculosis (MDR-TB) after completing pulmonary tuberculosis treatment (CPTBT). A matched case-control study (1:2 ratios) was performed between 2005 and 2018. A multivariable Cox regression analysis was used to evaluate independent predictors of incident MDR-TB after the CPTBT. A comprehensive nomogram was developed based on the multivariable Cox model. Overall, 1, 836 participants were included in this study. We developed and validated a simple-to-use nomogram that predicted the individualized risk of incident MDR-TB by using 10 parameters after the CPTBT. The concordance index of this nomogram was 0.833 [95% confidence interval (CI) 0.807-0.859] and 0.871 (95% CI 0.773-0.969) for the training and validation sets, respectively, which indicated adequate discriminatory power. The calibration curves for the risk of incident MDR-TB showed an optimal agreement between nomogram prediction and actual observation in the training and validation sets, respectively. The high sensitivity and specificity of nomogram was indicated by using a receiver operating characteristic curve analysis. Through this clinic tool, TB control executives could more precisely monitor, estimate and intervene the risk of incident MDR-TB among individuals with CPTBT.


Assuntos
Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Pulmonar/tratamento farmacológico , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nomogramas , Modelos de Riscos Proporcionais , Curva ROC , Análise de Regressão , Sensibilidade e Especificidade
19.
J Glob Antimicrob Resist ; 20: 1-3, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31698106

RESUMO

OBJECTIVES: A multidrug-resistant strain of the opportunistic pathogen Streptococcus sanguis (S28) was isolated from a throat swab of a child with scarlet fever as a rare case. Genome sequencing and analysis of strain S28 were performed to gain a better understanding of the multidrug resistance mechanisms of S. sanguis and its relationship with scarlet fever. METHODS: The genome of S. sanguis S28 was sequenced on a Illumina HiSeq platform. Genome assembly was conducted using SOAPdenovo v.2.04 and the assembled genome sequence was submitted to NCBI for annotation. RESULTS: The 1 268 358 696bp genome of S. sanguis S28 contains 2287 coding sequences (CDS) with a GC content of 43.2%. Strain S28 possesses four antimicrobial resistance genes (ARGs), which is consistent with phenotypic analysis. A novel transposon with three genes conferring resistance to macrolide-lincosamide-streptogramin B (MLSB) antibiotics, tetracyclines and aminoglycosides was discovered. CONCLUSION: To our knowledge, this is the first report of a S. sanguis genome isolated from a throat swab of a child with scarlet fever and the first report of a transposon with three activated ARGs conferring resistance to MLSB, tetracyclines and aminoglycosides together.


Assuntos
Farmacorresistência Bacteriana Múltipla , Escarlatina/microbiologia , Streptococcus sanguis/genética , Sequenciamento Completo do Genoma/métodos , Composição de Bases , Criança , Elementos de DNA Transponíveis , Tamanho do Genoma , Genoma Bacteriano , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Faringe/microbiologia , Fenótipo
20.
Cad Saude Publica ; 35(1): e00008418, 2019 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-30673056

RESUMO

The aim of this study is at examining the prevalence and impact factors of adolescent somatization tendencies (ST) across three eastern Chinese provinces. A multicenter school-based cross-sectional study was conducted in these provinces from 2015 to 2016. The sample included 11,153 middle-school students aged 13-18 years, who were randomly selected using a multi-phase stratified cluster sampling technique. We also designed a multicenter school-based case-control study to evaluate the potential environmental impact of ST factors on this population. The overall positive rate of ST among the eastern Chinese adolescents was 12.1%. Somatic symptoms score (SSS) and positive ST rate were higher in females than males. Additionally, the SSS and positive ST rate for the 18-year-old group were significantly higher than in other age groups. In comparison to those in urban areas, adolescents in rural areas had significantly higher SSS and positive ST rate. Multiple conditional regression analyses revealed that family medical history, anxiety and depression scores; superstitious beliefs; left-behind adolescents; teacher-student support; family conflict; and family independence and achievement orientation were significantly linked to ST in adolescents. The models also indicated family medical history was the strongest impact factor to adolescent ST, even though ST were prevalent in the three studied eastern Chinese provinces. Gender, age, and dwelling differences were very significant in the SSS and positive ST rate in adolescents. This study concludes that adolescent ST are influenced by multiple environments.


Assuntos
Meio Ambiente , Transtornos Somatoformes/epidemiologia , Inquéritos e Questionários/estatística & dados numéricos , Adolescente , Fatores Etários , Ansiedade/epidemiologia , Ansiedade/psicologia , Estudos de Casos e Controles , China/epidemiologia , Estudos Transversais , Depressão/epidemiologia , Depressão/psicologia , Saúde da Família/estatística & dados numéricos , Separação da Família , Feminino , Humanos , Masculino , Prevalência , Distribuição Aleatória , População Rural/estatística & dados numéricos , Fatores Sexuais , Fatores Socioeconômicos , Transtornos Somatoformes/psicologia , Superstições/psicologia , População Urbana/estatística & dados numéricos
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