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1.
Zhonghua Bing Li Xue Za Zhi ; 53(7): 716-721, 2024 Jul 08.
Artigo em Zh | MEDLINE | ID: mdl-38955704

RESUMO

Objectives: To investigate the mutation of PIK3CA in colorectal cancer and to analyze their clinicopathological features, and evaluate their role in clinical treatment and prognostication. Methods: A total of 128 paraffin-embbeded tissue samples of colorectal cancer from Shanxi Cancer Hospital from 2018 to 2021 were collected. DNA was extracted from the samples, and next-generation sequencing (NGS) was used to detect PIK3CA mutation. The relationship between PIK3CA mutation, their clinicopathological features, and prognosis were analyzed. Results: Among the 128 colorectal cancer samples, there were 75 males and 53 females; with aged range 32-86 years, median 61.5 years, 27 (21.09%) had PIK3CA mutations. Colorectal cancer with PIK3CA mutation was more likely to occur in male patients (P=0.007), which was related to tumor site (P=0.032), tumor size (P=0.029) and TP53 wild-type (P=0.001). The common site mutations of PIK3CA mostly occurred in tumors with tumor mutation burden≥10 Muts/Mb (P=0.031).PIK3CA mutation had no significant effect on the survival prognosis of patients, but the efficacy of anti-angiogenic therapy was poor in these patients. Conclusions: PIK3CA mutation is a common mutation in colorectal cancer and plays an important role in the occurrence and development of colorectal cancer. PIK3CA mutation may lead to resistance to anti-angiogenic drugs in colorectal cancer, but its impact on survival and prognosis to patients needs further study.


Assuntos
Classe I de Fosfatidilinositol 3-Quinases , Neoplasias Colorretais , Sequenciamento de Nucleotídeos em Larga Escala , Mutação , Humanos , Classe I de Fosfatidilinositol 3-Quinases/genética , Masculino , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Feminino , Pessoa de Meia-Idade , Idoso , Prognóstico , Adulto , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/uso terapêutico
2.
Zhonghua Jie He He Hu Xi Za Zhi ; 46(7): 697-699, 2023 Jul 12.
Artigo em Zh | MEDLINE | ID: mdl-37402660

RESUMO

Some patients who present with a "fever" may only have a localized increase in body surface temperature, while their core body temperature remains normal. This phenomenon is commonly referred to as pseudo fever. A retrospective analysis of clinical data from January 2013 to January 2020 at our fever clinic showed that 66 adolescents were diagnosed with pseudo fever. These patients typically showed a gradual increase in axillary temperature after their cold symptoms had disappeared. Most patients reported no significant complaints other than mild dizziness. Laboratory tests showed no significant abnormalities, and antipyretics were ineffective in lowering their body temperature. Pseudo fever is a relatively independent clinical phenomenon that is distinct from functional fever or simulated fever, and its underlying mechanism remains to be studied.


Assuntos
Antipiréticos , Febre , Humanos , Adolescente , Estudos Retrospectivos , Febre/diagnóstico , Temperatura Corporal
3.
Zhonghua Zhong Liu Za Zhi ; 42(7): 594-597, 2020 Jul 23.
Artigo em Zh | MEDLINE | ID: mdl-32842450

RESUMO

Objective: To investigate the progression-free survival (PFS) and safety of apatinib combined with docetaxel treated patients with advanced gastric cancer after failure of first-line chemotherapy. Methods: From March 2017 to May 2018, 23 patients with advanced gastric cancer who had received a failure of first-line chemotherapy (either fedocetaxel or paclitaxel) were treated with apatinib combined with docetaxel. The short-term efficacy and safety of the patients were observed. Results: The therapeutic effects of 20 patients were evaluated. Among them, 4 cases were partial response (PR), 13 patients were stable disease (SD), 3 patients were progressive disease (PD). The objective remission rate (ORR) was 20.0%, the disease control rate (DCR) was 85.0%, the median PFS (mPFS) was 4.5 months. The main adverse reactions were hypertension, vomiting and weakness. Conclusion: Apatinib combined with docetaxel applied in the second-line treatment of gastric cancer is safe and effective.


Assuntos
Antineoplásicos , Docetaxel , Piridinas , Neoplasias Gástricas , Antineoplásicos/uso terapêutico , Progressão da Doença , Docetaxel/uso terapêutico , Humanos , Piridinas/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico
4.
5.
Int J Dent Hyg ; 15(4): e85-e92, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27516401

RESUMO

OBJECTIVES: To compare differences in oral health-related quality of life (OHRQoL) between halitosis and non-halitosis patients and to explore relationships between halitosis and OHRQoL. METHODS: Patients who visited the halitosis clinic at the Ninth People's Hospital and were diagnosed with halitosis were included in the halitosis group. The control group consisted of patients without halitosis. All participants were assessed for halitosis (volatile sulphur compound measurements with a portable sulphide monitor, Oral Chroma and organoleptic tests), underwent a clinical oral examination (dental caries status and periodontal condition) and completed a questionnaire. Oral health-related quality of life was measured using the Oral Health Impact Profile (OHIP-14, Chinese version). RESULTS: A total of 204 patients (102 halitosis and 102 controls) were included. The halitosis group had significantly higher OHIP-14 scores (severity) than the control group (15.7 versus 7.9, P < 0.001). The mean number of items with negative impact (extent) was significantly different between the halitosis and control groups (1.8 versus 0.3, P < 0.001). Around 56% of participants in the halitosis group reported at least one item with 'fairly often' or 'very often' (prevalence), while 21% did so in the control group (P < 0.001). In halitosis patients, the most commonly reported negative impacts were within the domains of 'psychological discomfort' and 'psychological disability'. CONCLUSIONS: Oral health-related quality of life status was significantly poorer in halitosis patients than in non-halitosis patients. Halitosis patients may experience some degree of psychological discomfort and disability.


Assuntos
Halitose/complicações , Saúde Bucal , Qualidade de Vida , Adulto , China/epidemiologia , Feminino , Halitose/epidemiologia , Humanos , Masculino , Reprodutibilidade dos Testes , Inquéritos e Questionários
8.
Oral Dis ; 20(8): 787-95, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24134214

RESUMO

OBJECTIVES: To describe the characteristics of patients who visited halitosis clinic and to investigate the factors that may associate with halitosis. MATERIALS AND METHODS: Nine hundred and eleven patients, who visited halitosis clinic for consultations, underwent organoleptic tests and volatile sulfur compound (VSC) measurements with a portable sulfide monitor. The oral health of patients, including dental caries, oral hygiene, and gingival inflammation status, was assessed. Questionnaires were used to obtain information on demographics, oral hygiene practices, and dietary habits. RESULTS: Of the 911 patients, more females than males visited the clinic. Patients' age ranged from 18 to 82 years (mean ± s.d.: 40.8 ± 14.1). Almost 30% of patients had complained of halitosis for over 5 years before looking into treatments. Approximately half of the patients self-perceived that they were unable to get close to others. Around 77% of patients had halitosis. Results of multiple logistic regressions for organoleptic scores and VSC values showed that tongue coating and tongue scraping were significantly associated with halitosis (P < 0.05). CONCLUSIONS: Among these Chinese patients, over three-quarters of patients had halitosis, and negative impacts on social communications were observed. Tongue coating was the most important factor responsible for halitosis.


Assuntos
Halitose/fisiopatologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Relações Interpessoais , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
J Dent Res ; 102(1): 72-81, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35983582

RESUMO

Nuclear receptor corepressor 1 (Ncor1) has been reported to regulate different transcription factors in different biological processes, including metabolism, inflammation, and circadian rhythms. However, the role of Ncor1 in periodontitis has not been elucidated. The aims of the present study were to investigate the role of Ncor1 in experimental periodontitis and to explore the underlying mechanisms through an experimental periodontitis model in myeloid cell-specific Ncor1-deficient mice. Myeloid cell-specific Ncor1 knockout (MNKO) mice were generated, and experimental periodontitis induced by ligation using 5-0 silk sutures was established. Ncor1 flox/flox mice were used as littermate controls (LC). Histological staining and micro-computed tomography scanning were used to evaluate osteoclastogenesis and alveolar bone resorption. Flow cytometry was conducted to observe the effect of Ncor1 on myeloid cells. RNA sequencing was used to explore the differentially targeted genes in osteoclastogenesis in the absence of Ncor1. Coimmunoprecipitation (Co-IP), chromatin immunoprecipitation (ChIP) experiments, and dual luciferase assays were performed to explore the relationship between NCoR1 and the targeted gene. Alveolar bone resorption in the MNKO mice was significantly greater than that in the LC mice after periodontitis induction and osteoclastogenesis in vitro. The percentage of CD11b+ cells, particularly CD11b+ Ly6G+ neutrophils, was substantially higher in gingival tissues in the MNKO mice than in the LC mice. Results of RNA sequencing demonstrated that CCAAT enhancer binding protein α (Cebpα) was one of the most differentially expressed genes between the MNKO and LC groups. Mechanistically, Co-IP assays, ChIP experiments, and dual luciferase assays revealed that NCOR1 interacted with peroxisome proliferator-activated receptor gamma (PPARγ) and cooperated with HDAC3 to control the transcription of Cebpα. In conclusion, Ncor1 deficiency promoted osteoclast and neutrophil formation in mice with experimental periodontitis. It regulated the transcription of Cebpα via PPARγ to promote osteoclast differentiation.


Assuntos
Perda do Osso Alveolar , Periodontite , Camundongos , Animais , Osteogênese , PPAR gama/metabolismo , Microtomografia por Raio-X , Periodontite/metabolismo , Osteoclastos/metabolismo , Perda do Osso Alveolar/metabolismo , Correpressor 1 de Receptor Nuclear/genética , Correpressor 1 de Receptor Nuclear/metabolismo
10.
Int J Paediatr Dent ; 22(2): 77-84, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21771124

RESUMO

BACKGROUND: Longitudinal study to investigate how the dental caries in primary teeth progress with increasing age is still lacking. Aims. To describe the development of new caries over 2years and to identify risk factors that can predict new caries development. DESIGN: A random sample of preschool children aged 3-4years was surveyed and followed up when they reached 5-6years of age in Hong Kong. Dental caries status was assessed using the dmft index. Negative binomial regression was performed to investigate the factors collected at baseline that could predict the caries increment over 2years. RESULTS: Totally 358 children attended both examinations. The mean caries increment over 2years was 0.9. Results of the negative binomial regression showed that children who used nursing bottles during sleep when they were young (P=0.013), whose toothbrushing began after 12months (P=0.005), who took snack once or more daily (P<0.001), and whose parents had 9 or fewer years of education attainment (P=0.002) had significantly higher caries increment. CONCLUSIONS: New caries development of Hong Kong preschool children was low. Children's feeding, snaking and brushing habits, and parents' education attainment were the significant predictors for new caries development of preschool children.


Assuntos
Suscetibilidade à Cárie Dentária , Cárie Dentária/epidemiologia , Comportamento Alimentar , Higiene Bucal/estatística & dados numéricos , Dente Decíduo/patologia , Criança , Pré-Escolar , Índice CPO , Cárie Dentária/patologia , Cárie Dentária/prevenção & controle , Feminino , Hong Kong , Humanos , Estudos Longitudinais , Masculino , Saúde Bucal/estatística & dados numéricos , Estudos Prospectivos , Fatores Socioeconômicos , Escovação Dentária/estatística & dados numéricos
11.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 56(2): 200-203, 2021 Feb 09.
Artigo em Zh | MEDLINE | ID: mdl-33557506

RESUMO

As the national key discipline and the initiator of oral and maxillofacial deformity group, the Department of Oral and Maxillofacial Surgery persisted in teaching, designed a novel teaching form combining theoretical knowledge and online software practice according to the characteristics of our discipline and carried out "cloud training" via the National Oral Telemedicine Education Platform. Ten lecturers, 325 theoretical students and 50 practical students were investigated by questionnaire in the present study with questions focusing on the geographical distribution and composition of personnel, etc. The results showed that the online course covered a wide range of students and achieved high acceptance and satisfaction rate. The first online software operation course was conducted in an orderly manner, with timely interaction between teachers and students. The students were able to master the design process skillfully. This "cloud training" has achieved good results, but there are still a series of problems that have yet to be resolved, such as network stalls and protection of intellectual property rights. Under the new form, the exploration and analysis of the new mode of online telemedicine specialist education will provide some practical reference for the National Clinical Research Center for Oral Diseases to carry out online telemedicine teaching in the future.


Assuntos
COVID-19 , Educação Médica , China , Hospitais , Humanos , Pandemias , SARS-CoV-2
12.
J Dent Res ; 100(5): 496-506, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33283631

RESUMO

Comprehensive research on ethnic disparities in dental caries in China is limited. The aims of this cross-sectional study were to compare the levels of dental caries in adolescents between the Han ethnic group and ethnic minority groups in China and to explore the risk indicators for dental caries within ethnic subgroups. Data from the Fourth National Oral Health Survey in 2015, which covered all 31 province-level administrative divisions in mainland China, were used. The dental caries status in the permanent dentition of adolescents aged 12, 13, 14, and 15 y was measured using the decayed, missing, and filled teeth (DFMT) score, and sociodemographic characteristics and oral health-related behaviors were also collected. A total of 118,601 adolescents were included, with ethnic minority groups accounting for 13.15%. Of the Han and minority groups, the standardized prevalence of dental caries experience was 40.58% and 47.67%, and the mean DMFT scores were 0.97 and 1.28, respectively. According to the multivariate zero-inflated negative binomial regression analysis, the caries status of minorities was more severe than Han adolescents (adjusted prevalence rate ratio [PRR], 1.14; 95% confidence interval [CI], 1.10-1.18). This disparity was greater among adolescents who lived in rural areas, had mid-level economic status, and frequently consumed sugary beverages. After propensity score matchings, Uygur (PRR, 1.44; 95% CI, 1.25-1.67), Tibetan (PRR, 1.39; 95% CI, 1.3-1.48), and Yi (PRR, 1.24; 95% CI, 1.04-1.48) adolescents were significantly more likely to have caries than Han adolescents. Subgroup analyses revealed that gender, age, location of residence, economic status, region, consumption of sweet snacks and sugary beverages, and dental visit pattern were significantly associated with dental caries within ethnic minorities.


Assuntos
Cárie Dentária , Etnicidade , Adolescente , Criança , China/epidemiologia , Estudos Transversais , Índice CPO , Cárie Dentária/epidemiologia , Humanos , Grupos Minoritários , Prevalência
13.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(3): 354-357, 2020 Mar 10.
Artigo em Zh | MEDLINE | ID: mdl-32294834

RESUMO

Objective: To explore influence on physical development of children aged 18 months from HIV-positive mothers for prevention mother to child transmission of HIV (PMTCT) in Guangxi Zhuang autonomous region, and provide evidence for the improvement PMTCT program. Methods: This retrospective case control study was conducted in 554 HIV negative infants aged 18 months whose HIV positive mothers had received PMTCT services reported through PMTCT system database from January 1, 2010 to December 31, 2017 and 1 109 healthy infants born in 2017, whose mothers were healthy, in Lingshan, Luzhai, and Hengxian counties, ranking top three counties with high HIV infection prevalence, in Guangxi. PMTCT data and physical development data such as height, weight and head circumference of children aged 18 months were collected. The physical dysplasia in the infants was defined as at least one of the three main indicators of height, weight and head circumference below the normal range. Results: The number of HIV-positive mother and their infants in the case group were 667 and 554 respectively, and the PMTCT rates were 91.15% (608/667) and 96.57% (535/554) respectively. HIV positive rate, mortality rate and mother to child transmission rate of the infants aged 18 months were 1.44% (8/554), 3.07% (17/554) and 1.91% (8/418) respectively, and the physical examination results of the infants aged 18 months showed that the physical dysplasia rate was 30.51% (169/554). Among the 1 109 infants in the control group, the physical dysplasia rate was 9.83% (109/1 109). The difference between the case group and the control group was significant (P<0.01). Conclusion: The PMTCT rates of HIV positive mother and their children were more than 90.00%, respectively. However, poor physical development rate of infants aged 18 months were more than 30.00%. The possible influence of PMTCT on physical development of the infants aged 18 months of HIV positive mother's needs to be further studied.


Assuntos
Desenvolvimento Infantil , Infecções por HIV/transmissão , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Complicações Infecciosas na Gravidez , Estudos de Casos e Controles , China , Feminino , Humanos , Lactente , Gravidez , Estudos Retrospectivos
14.
Tissue Antigens ; 74(5): 440-2, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19845900

RESUMO

A novel HLA-B allele, B*4096, has been identified in a Chinese individual by sequence-based typing, which has seven nucleotide changes from the closest matching allele B*40060101 resulting in five amino acid changes: 101Ser-->Asn; 104Ser-->Thr; 105Leu-->Ala; 106Arg--> Leu and 107Gly-->Arg.


Assuntos
Povo Asiático/genética , Antígenos HLA-B/genética , Teste de Histocompatibilidade , Alelos , Substituição de Aminoácidos/genética , Sequência de Bases , Teste de Histocompatibilidade/métodos , Humanos , Dados de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA/métodos , Homologia de Sequência do Ácido Nucleico
15.
J Int Med Res ; 37(3): 631-40, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19589245

RESUMO

Paris polyphylla has been used to treat cancer in China for many years and components of the plant, such as polyphyllin D, may have potent antiproliferative effects in vitro. To investigate the potential antitumour effects of polyphyllin D on cancer cells under hypoxia, Lewis lung cancer cells and mouse tracheal epithelial cells were cultured with or without polyphyllin D under normoxic and hypoxic conditions. Proliferation and apoptosis of cells were assayed. Real-time reverse transcription-polymerase chain reaction was used to quantify the expression of hypoxia-inducible factor 1 alpha (HIF-1alpha) and vascular endothelial growth factor (VEGF) mRNA. Polyphyllin D decreased cell proliferation, increased apoptosis and inhibited expression of HIF-1alpha and VEGF mRNAs in Lewis cells. These effects were greater under hypoxic than normoxic conditions. Polyphyllin D did not show a cytotoxic effect in non-tumour cells (mouse skin fibroblasts and tracheal epithelial cells). These results suggest that polyphyllin D potentially has anticancer effects in vitro under hypoxia.


Assuntos
Carcinoma Pulmonar de Lewis/patologia , Diosgenina/análogos & derivados , Animais , Apoptose/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Diosgenina/química , Diosgenina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Camundongos , Invasividade Neoplásica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Saponinas , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
16.
Animal ; 12(8): 1611-1620, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29198215

RESUMO

l-Arginine is a nutritionally essential amino acid for spermatogenesis and plays versatile roles in animal health and can be utilized as a potential agent to improve reproductive performance of boars under high ambient temperature. The present study aimed to determine whether dietary l-arginine could alleviate heat stress-induced infertility in boars. In all, 20 boars (PIC 1040; 248.59±3.84 kg BW and 407.65±6.40 days of age) were selected and randomly assigned to four groups (group 0.0%, basal diet; group 0.6%, 0.8% or 1.0%, basal diet added with 0.6%, 0.8% or 1.0% l-arginine (wt:wt), respectively.) The four diets were made isonitrogenous by addition of appropriate amounts of l-alanine. Boars were pre-fed the corresponding experimental diet for 42 days. Then, the semen characteristics and libido were accessed for 6 weeks during the hot summer period (25.5° to 33.0°C). Results show that dietary l-arginine remarkably improved sperm motility, normality, total sperm number and effective total sperm number. Also, dietary l-arginine improved semen antioxidant capacity, such as decrease of malondialdehyde and 8-Hydroxy-2'-deoxyguanosine content in sperm (P<0.05), increase of the ratio of glutathione and oxidized glutathione, total antioxidant capacity, glutathione peroxidase and catalase activities in seminal plasma (P<0.05). Most of mitochondria contained intact ultrastructure in l-arginine-supplemented group which also accompany with higher ATP content than the 0.0% group. The boars fed 0.8% l-arginine show increased levels of estradiol-17ß and testosterone and exhibit improved libido performance than boars in the 0.0% group. Adding dietary l-arginine linearly increased (P=0.002) nitric oxide content (as l-arginine increased). The scrotal surface temperature in the 0.6%, 0.8% and 1.0% group were decreased by 0.9°C, 0.9°C and 0.4°C, respectively, compared with the 0.0% group. l-Arginine levels caused linear effect on semen quality and antioxidant capacity, also caused quadratic effect on libido performance. During the hot summer months, the predicted optimal l-arginine levels for best semen quality and antioxidant capacity was 0.8% to 1.0% and for best libido performance was 0.8%. It can be concluded that l-arginine can be used as an effective agent to alleviate heat stress-induced infertility of boar, and that 0.8% to 1.0% can be considered as the optimum dosage.


Assuntos
Ração Animal , Arginina , Libido , Motilidade dos Espermatozoides , Suínos , Animais , Arginina/farmacologia , Masculino , Sêmen , Análise do Sêmen , Espermatozoides , Suínos/fisiologia , Temperatura
17.
Zhonghua Liu Xing Bing Xue Za Zhi ; 39(4): 487-490, 2018 Apr 10.
Artigo em Zh | MEDLINE | ID: mdl-29699043

RESUMO

Objective: To understand the dynamic variation of BMI and influencing factors among HIV/AIDS patients receiving highly active anti-retroviral therapy (HAART) in Liuzhou, Guangxi Zhuang Autonomous Region (Guangxi). Methods: HIV/AIDS patients receiving HAART for the first time since 1 January 2013 were selected. Data on BMI was analyzed among patients receiving HAART at baseline,6 months and 12 months after treatment. By using the general linear model repeated measures of analysis of variance, BMI dynamic variations and influencing factors were described and analyzed. Results: The average BMI of 2 871 patients at baseline, 6th months and 12th months appeared as (20.65±3.32), (20.87±3.22) and (21.18±3.20), respectively, with differences all statistically significant (F=18.86, P<0.001). BMI were increasing over time with treatments (F=37.25, P<0.001). Main influencing factors were noticed as: age, sex, marital status, baseline data of CD(4)(+)T cells and the WHO classification on clinical stages. Conclusions: Higher proportion of BMI malnutrition counts was seen among patients before receiving HAART in Liuzhou. BMI of the patients that were on HAART seemed being influenced by many factors. It is necessary to select appropriate treatment protocols on different patients so as to improve the nutritional status of the patients.


Assuntos
Terapia Antirretroviral de Alta Atividade , Índice de Massa Corporal , Infecções por HIV/tratamento farmacológico , Síndrome da Imunodeficiência Adquirida , Contagem de Linfócito CD4 , China/epidemiologia , Humanos , Modelos Lineares , Estado Civil , Estado Nutricional , Linfócitos T
18.
Sci Total Environ ; 605-606: 180-189, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28667845

RESUMO

Secondary organic aerosol (SOA) is an important constituent of airborne fine particles. PM2.5 (particles with aerodynamic diameters≤2.5µm) samples were collected at a mountainous site in Hong Kong in autumn of 2010, and analyzed for SOA tracers. Results indicated that the concentrations of isoprene SOA tracers (54.7±22.7ng/m3) and aromatics SOA tracers (2.1±1.6ng/m3) were on relatively high levels in Hong Kong. Secondary organic carbon (SOC) derived from isoprene, monoterpenes, sesquiterpenes and aromatics was estimated with the SOA tracer based approach, which constituted 0.35±0.15µg/m3 (40.6±5.7%), 0.20±0.03µg/m3 (30.4±5.5%), 0.05±0.02µg/m3 (5.6±1.7%) and 0.26±0.20µg/m3 (21.3±8.2%) of the total estimated SOC. Biogenic SOC (0.60±0.18µg/m3) dominated over anthropogenic SOC (0.26±0.20µg/m3) at this site. In addition to the total estimated SOC (17.8±4.6% of organic carbon (OC) in PM2.5), primary organic carbon (POC) emitted from biomass burning also accounted for a considerable proportion of OC (11.6±3.2%). Insight into the OC origins found that regional transport significantly (p<0.05) elevated SOC from 0.37±0.17 to 1.04±0.39µg/m3. Besides, SOC load could also increase significantly if there was influence from local ship emission. Biomass burning related POC in regional air masses (0.81±0.24µg/m3) was also higher (p<0.05) than that in samples affected by local air (0.29±0.35µg/m3). Evidences indicated that SOA formation was closely related to new particle formation and the growth of nucleation mode particles, while biomass burning was responsible for some particle burst events in Hong Kong. This is the first SOA study in afforested areas of Hong Kong.

19.
Zhonghua Liu Xing Bing Xue Za Zhi ; 38(3): 326-330, 2017 Mar 10.
Artigo em Zh | MEDLINE | ID: mdl-28329933

RESUMO

Objective: To understand HIV-1 subtype characteristics and transmission clusters in elderly male clients and female sex workers (FSWs) of low-cost commercial sex venues in Guangxi Zhuang Autonomous Region, China. Methods: A cross sectional survey was conducted in FSWs and elderly male clients (≥50 years) of low-cost commercial sex venues in 4 cities and 9 counties in Guangxi Zhuang Autonomous Region by convenient sampling in 2012. The blood sample was collected from each case for HIV-1 antibody detection. The pol gene fragments were amplified and sequenced from viral RNA template extracted from plasma samples. The phylogenetic tree was constructed and the subtypes were identified. Results: A total of 4 048 elderly male clients and 784 FSWs were surveyed, and 116 HIV-1 infections were detected, the positive rate was 2.5% (103/4 048) in the clients and 1.7% (13/784) in FSWs. The gene amplification and sequencing of HIV-1 detected in 84 blood samples indicated that 53 pol gene sequences were successfully determined (48 blood samples from elderly male clients and 5 blood samples from FSWs). Among 53 pol sequences, 48(90.6% ), 4(7.5% ), and 1(1.9% ) sequences were identified as CRF01_AE, CRF08_BC, and CRF07_BC, respectively. Two transmission clusters were identified among CRF01_AE, including 4 sub-clusters. One transmission cluster was identified among CRF08_BC. The transmission cluster or sub-cluster were from the infected individuals at same low-cost commercial sex venue, or different low-cost commercial sex venues in the same town, or same place, or adjacent villages and towns. Conclusions: CRF01_AE was the predominant HIV-1 subtype among elderly male clients and FSWs of low-cost commercial sex venues in Guangxi Zhuang Autonomous Region, circulating in same venue or adjacent villages and towns. The HIV-1 positive male clients and FSWs might play an important role in the spread of the strains.


Assuntos
Infecções por HIV/epidemiologia , HIV-1/genética , Profissionais do Sexo , Produtos do Gene pol do Vírus da Imunodeficiência Humana/genética , Fatores Etários , Idoso , Sequência de Bases , China/epidemiologia , Estudos Transversais , Feminino , Genes pol , Genótipo , Anticorpos Anti-HIV , Infecções por HIV/transmissão , Infecções por HIV/virologia , Humanos , Masculino , Filogenia , Reação em Cadeia da Polimerase , RNA Viral/sangue , Características de Residência , Trabalho Sexual
20.
Sci Total Environ ; 574: 1021-1043, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27668854

RESUMO

Photochemical smog, characterized by high concentrations of ozone (O3) and fine particles (PM2.5) in the atmosphere, has become one of the top environmental concerns in China. Volatile organic compounds (VOCs), one of the key precursors of O3 and secondary organic aerosol (SOA) (an important component of PM2.5), have a critical influence on atmospheric chemistry and subsequently affect regional and global climate. Thus, VOCs have been extensively studied in many cities and regions in China, especially in the North China Plain, the Yangtze River Delta and the Pearl River Delta regions where photochemical smog pollution has become increasingly worse over recent decades. This paper reviews the main studies conducted in China on the characteristics and sources of VOCs, their relationship with O3 and SOA, and their removal technology. This paper also provides an integrated literature review on the formulation and implementation of effective control strategies of VOCs and photochemical smog, as well as suggestions for future directions of VOCs study in China.

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