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1.
Mol Biol Evol ; 40(5)2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37134013

RESUMO

HIV-1 is a highly host-specific retrovirus that infects humans but not most nonhuman primates. Thus, the lack of a suitable primate model that can be directly infected with HIV-1 hinders HIV-1/AIDS research. In the previous study, we have found that the northern pig-tailed macaques (NPMs) are susceptible to HIV-1 infection but show a nonpathogenic state. In this study, to understand this macaque-HIV-1 interaction, we assembled a de novo genome and longitudinal transcriptome for this species during the course of HIV-1 infection. Using comparative genomic analysis, a positively selected gene, Toll-like receptor 8, was identified with a weak ability to induce an inflammatory response in this macaque. In addition, an interferon-stimulated gene, interferon alpha inducible protein 27, was upregulated in acute HIV-1 infection and acquired an enhanced ability to inhibit HIV-1 replication compared with its human ortholog. These findings coincide with the observation of persistently downregulated immune activation and low viral replication and can partially explain the AIDS-free state in this macaque following HIV-1 infection. This study identified a number of unexplored host genes that may hamper HIV-1 replication and pathogenicity in NPMs and provided new insights into the host defense mechanisms in cross-species infection of HIV-1. This work will facilitate the adoption of NPM as a feasible animal model for HIV-1/AIDS research.


Assuntos
Infecções por HIV , HIV-1 , Vírus da Imunodeficiência Símia , Animais , Humanos , Macaca nemestrina , HIV-1/genética , Genômica , Vírus da Imunodeficiência Símia/genética
2.
J Virol ; 97(4): e0020023, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-36971578

RESUMO

Tetherin prevents viral cross-species transmission by inhibiting the release of multiple enveloped viruses from infected cells. With the evolution of simian immunodeficiency virus of chimpanzees (SIVcpz), a pandemic human immunodeficiency virus type 1 (HIV-1) precursor, its Vpu protein can antagonize human tetherin (hTetherin). Macaca leonina (northern pig-tailed macaque [NPM]) is susceptible to HIV-1, but host-specific restriction factors limit virus replication in vivo. In this study, we isolated the virus from NPMs infected with strain stHIV-1sv (with a macaque-adapted HIV-1 env gene from simian-human immunodeficiency virus SHIV-KB9, a vif gene replaced by SIVmac239, and other genes originating from HIV-1NL4.3) and found that a single acidic amino acid substitution (G53D) in Vpu could increase its ability to degrade the tetherin of macaques (mTetherin) mainly through the proteasome pathway, resulting in an enhanced release and resistance to interferon inhibition of the mutant stHIV-1sv strain, with no influence on the other functions of Vpu. IMPORTANCE HIV-1 has obvious host specificity, which has greatly hindered the construction of animal models and severely restricted the development of HIV-1 vaccines and drugs. To overcome this barrier, we attempted to isolate the virus from NPMs infected with stHIV-1sv, search for a strain with an adaptive mutation in NPMs, and develop a more appropriate nonhuman primate model of HIV-1. This is the first report identifying HIV-1 adaptations in NPMs. It suggests that while tetherin may limit HIV-1 cross-species transmission, the Vpu protein in HIV-1 can overcome this species barrier through adaptive mutation, increasing viral replication in the new host. This finding will be beneficial to building an appropriate animal model for HIV-1 infection and promoting the development of HIV-1 vaccines and drugs.


Assuntos
Antígeno 2 do Estroma da Médula Óssea , HIV-1 , Macaca , Proteínas Virais , Liberação de Vírus , HIV-1/genética , HIV-1/patogenicidade , Proteínas Virais/genética , Proteínas Virais/metabolismo , Mutação , Antígeno 2 do Estroma da Médula Óssea/metabolismo , Ubiquitina/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Liberação de Vírus/genética , Substituição de Aminoácidos/genética , Infecções por HIV/virologia , Modelos Animais de Doenças , Replicação Viral/genética
3.
Hepatology ; 75(6): 1566-1578, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34855999

RESUMO

BACKGROUND AND AIMS: Hepatitis B vaccine has been included in the infant immunization schedule since 1991 in the United States. We aimed to assess its effectiveness against HBV infection and its impact on mortality. APPROACH AND RESULTS: The study population was participants aged 6+ years with an HBV vaccination history and an HBV serologic test from the National Health and Nutrition Examination Survey, 1999-2018. Participants aged 18+ years with linked mortality records from 1999-2014 were followed for mortality analysis. Multivariable logistic regression was used to compute vaccine effectiveness (VE) overall, by year of birth, and by age. Cox regression was used to estimate HRs for all-cause, cancer-related, and cardiovascular disease-related mortality. A total of 64,107 participants were included in the main analysis, with 29,600 (40.7%) having completed HBV vaccination (three or more doses, vaccinated). The highest vaccination uptake was found among those born after 1991, at 86.5%. Vaccinated participants had higher prevalence of vaccine-induced immunity than the unvaccinated (47.2% vs. 7.4%). Among those born after 1991, VE was found at 58% (95% CI, 18%-79%) overall and 85% for those aged ≥20 years (mean age, 22), whereas no effect was found among those born prior to 1990. HBV vaccination was associated with reduced risk of all-cause mortality (HR, 0.78; 95% CI, 0.68-0.90) and cancer-related mortality (HR, 0.76; 95% CI, 0.58-1.00) but not for cardiovascular disease-related mortality. CONCLUSIONS: In the universal infant vaccination era, the HBV vaccine has shown substantial effectiveness against HBV infection and maintained strong protection for 20 years. It was also associated with reduced risk of all-cause and cancer-related mortality.


Assuntos
Doenças Cardiovasculares , Hepatite B , Neoplasias , Adulto , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Anticorpos Anti-Hepatite B , Antígenos de Superfície da Hepatite B , Vacinas contra Hepatite B , Humanos , Programas de Imunização , Lactente , Inquéritos Nutricionais , Estados Unidos/epidemiologia , Vacinação , Adulto Jovem
4.
Paediatr Perinat Epidemiol ; 37(4): 303-312, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36991572

RESUMO

BACKGROUND: Administrative health data has been used extensively to examine congenital heart disease (CHD). However, the accuracy and completeness of these data must be assessed. OBJECTIVES: To use data linkage of multiple administrative data sources to examine the validity of identifying CHD cases recorded in hospital discharge data. METHODS: We identified all liveborn infants born 2013-2017 in New South Wales, Australia with a CHD diagnosis up to age one, recorded in hospital discharge data. Using record linkage to multiple data sources, the diagnosis of CHD was compared with five reference standards: (i) multiple hospital admissions containing CHD diagnosis; (ii) receiving a cardiac procedure; (iii) CHD diagnosis in the Register of Congenital Conditions; (iv) cardiac-related outpatient health service recorded; and/or (v) cardiac-related cause of death. Positive predictive values (PPV) comparing CHD diagnosis with the reference standards were estimated by CHD severity and for specific phenotypes. RESULTS: Of 485,239 liveborn infants, there were 4043 infants with a CHD diagnosis identified in hospital discharge data (8.3 per 1000 live births). The PPV for any CHD identified in any of the five methods was 62.8% (95% confidence interval [CI] 60.9, 64.8), with PPV higher for severe CHD at 94.1% (95% CI 88.2, 100). Infant characteristics associated with higher PPVs included lower birthweight, presence of a syndrome or non-cardiac congenital anomaly, born to mothers aged <20 years and residing in disadvantaged areas. CONCLUSION: Using data linkage of multiple datasets is a novel and cost-effective method to examine the validity of CHD diagnoses recorded in one dataset. These results can be incorporated into bias analyses in future studies of CHD.


Assuntos
Cardiopatias Congênitas , Alta do Paciente , Feminino , Humanos , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/epidemiologia , Hospitalização , Armazenamento e Recuperação da Informação , Hospitais
5.
Epidemiol Infect ; 151: e37, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36789960

RESUMO

This study aimed to assess human papillomavirus (HPV) vaccine effectiveness (VE) against both vaccine-type and nonvaccine-type high-risk HPV (hrHPV) infection, and duration of protection in United States. The study population was female participants aged 18-35 years with an HPV vaccination history and genital testing for HPV from the National Health and Nutrition Examination Survey, 2007-2016. Participants vaccinated before sexual debut were assessed against 13 nonvaccine-type hrHPV infection including 31/33/35/39/45/51/52/56/58/59/68/73/82. Multivariable logistic regression was used to estimate VE overall, by age at diagnosis, time since vaccination and lifetime sexual partners. A total of 3866 women were included in the analysis, with 23.3% (95% CI 21.3%-25.4%) having been vaccinated (≥1 dose). VE against vaccine-type HPV18/16/11/6 infection was 58% overall, which was mainly driven by those aged 18-22 years (VE = 64%) and 23-27 years (65%). Among participants aged 18-22 years vaccinated before sexual debut, the VE was 47% (23%-64%) against 13 nonvaccine-type hrHPV and 61% (95% CI 36%-77%) against 5 selected nonvaccine-type hrHPV35/39/52/58/59. Both direct effectiveness and cross-protection maintained effective for 5-10 years post vaccination. We also found the prevalence of ever diagnosed cervical cancer among vaccinated was significantly lower (0.46%, 4/874) than that among unvaccinated participants (1.27%, 38/2992). These findings highlight the potential of significant reduction of cervical cancer following the universal HPV vaccination programme.


Assuntos
Infecções por Papillomavirus , Vacinas contra Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/prevenção & controle , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/prevenção & controle , Inquéritos Nutricionais , Vacinação
6.
BMC Pregnancy Childbirth ; 23(1): 203, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36964492

RESUMO

BACKGROUND: Evidence regarding the association between acute respiratory infections during pregnancy and congenital anomalies in babies, is limited and conflicting. The aim of this study was to examine the association between acute respiratory infections during the first trimester of pregnancy and congenital anomalies in babies using record linkage. METHODS: We linked a perinatal register to hospitalisation and disease notifications in the Australian state of New South Wales (NSW) between 2001 to 2016. We quantified the risk of congenital anomalies, identified from the babies' linked hospital record in relation to notifiable respiratory and other infections during pregnancy using generalized Estimating Equations (GEE) adjusted for maternal sociodemographic and other characteristics. RESULTS: Of 1,453,037 birth records identified from the perinatal register between 2001 and 2016, 11,710 (0.81%) mothers were hospitalised for acute respiratory infection, 2850 (0.20%) had influenza and 1011 (0.07%) had high risk infections (a record of cytomegalovirus, rubella, herpes simplex, herpes zoster, toxoplasmosis, syphilis, chickenpox (varicella) and zika) during the pregnancy. During the first trimester, acute respiratory infection, influenza and high-risk infections were reported by 1547 (0.11%), 399 (0.03%) and 129 (0.01%) mothers. There were 15,644 (1.08%) babies reported with major congenital anomalies, 2242 (0.15%) with cleft lip/ plate, 7770 (0.53%) with all major cardiovascular anomalies and 1746 (0.12%) with selected major cardiovascular anomalies. The rate of selected major cardiovascular anomalies was significantly higher if the mother had an acute respiratory infection during the first trimester of pregnancy (AOR 3.64, 95% CI 1.73 to 7.66). The rates of all major congenital anomalies and all major cardiovascular anomalies were also higher if the mother had an acute respiratory infection during the first trimester of pregnancy, however the difference was no statistically significant. Influenza during the first trimester was not associated with major congenital anomalies, selected major cardiovascular anomalies or all major cardiovascular anomalies in this study. CONCLUSION: This large population-based study found severe acute respiratory infection in first trimester of pregnancy was associated with a higher risk of selected major cardiovascular anomalies in babies. These findings support measures to prevent acute respiratory infections in pregnant women including through vaccination.


Assuntos
Influenza Humana , Infecção por Zika virus , Zika virus , Recém-Nascido , Gravidez , Feminino , Humanos , Estudos de Coortes , Austrália , Primeiro Trimestre da Gravidez , Parto
7.
Liver Int ; 42(10): 2299-2316, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35779247

RESUMO

AIMS: This study aims to compare estimates of primary liver cancer mortality from World Health Organization (WHO), Global Burden Disease (GBD) and Global Cancer Observatory (GCO). METHODS: Liver cancer mortality was extracted from WHO, GBD and GCO for 92 countries for the most recent year. Age-standardized rate (ASR) was computed and used for current comparisons across the three data sources. Temporal trend for 75 countries was analysed and compared between WHO and GBD from 1990 to 2019 using joinpoint regression. Average annual percentage change for the most recent 10 years was used as indicator for change. RESULTS: The estimates of ASR were quite consistent across the three data sources, but most similar estimates were found between WHO and GCO in both region and country levels. The differences in ASR were negatively correlated with completeness of cause-of-death registration, human development index and proportion of liver cancer because of alcohol consumption. Consistent trends of ASR were found from 35 countries between WHO and GBD in the most recent 10 years. However, opposite trends were found from 10 countries with five from Southern America, four from Europe and one from Asia. Of the 18 countries for projection, opposite trends between WHO and GBD were found from seven countries. CONCLUSION: While the ASR of primary liver cancer mortality was comparable across the three data sources, most similar estimates were found between WHO and GCO. The opposite trends found from 10 countries between WHO and GBD raised concerns of true patterns in these countries.


Assuntos
Carga Global da Doença , Neoplasias Hepáticas , Ásia , Saúde Global , Humanos , Mortalidade , Organização Mundial da Saúde
8.
Dig Dis Sci ; 67(6): 2600-2607, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-33945063

RESUMO

BACKGROUND: Regular monitoring and treatment of chronic hepatitis B (CHB) are known to reduce the risk of hepatocellular carcinoma. We sought to describe patterns of monitoring and treatment among adults diagnosed with CHB in Australia. METHODS: Population-based prospective cohort study of Australian adults aged 45 + years followed by record-linkage to hepatitis B notifications, monitoring and treatment. Proportions of those with CHB who: had viral load test; were dispensed antiviral treatment; and had ultrasound surveillance were estimated. The characteristics associated with viral load test and ultrasound surveillance were examined using logistic regression. RESULTS: A total of 576 adults with CHB were identified. From 2008 to 2015, 14.8% (85/576) had at least one viral load test recorded every 2 years and 19.1% (110/576) had at least one antiviral treatment recorded, 19.9% (58/292) had at least one ultrasound recorded every year among those eligible for ultrasound surveillance. A record of having at least one viral load test every 2 years was more likely among adults born in Asia compared to Australian-born (21.4% vs 8.6%), those notified in more recent years compared to earlier years, and those on antiviral treatment compared to not on treatment. Increasing proportions of cases had records of at least one viral load test over time (2008: 10.5%, 2015: 27.2%) and at least one antiviral treatment (2008: 3.0%, 2015: 18.5%). CONCLUSIONS: In Australian adults, estimates of care interventions for CHB management have increased over time but still fall short of targets recommended in the National Hepatitis B Strategy.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Neoplasias Hepáticas , Adulto , Antivirais/uso terapêutico , Austrália/epidemiologia , Carcinoma Hepatocelular/epidemiologia , Estudos de Coortes , Vírus da Hepatite B , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/epidemiologia , Humanos , Neoplasias Hepáticas/epidemiologia , Estudos Prospectivos , Carga Viral
9.
Gynecol Oncol ; 163(3): 583-592, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34688503

RESUMO

BACKGROUNDS: This study investigated the global incidence and mortality of cervical cancer, its predictors, the temporal trend by country and age. METHODS: Data from Global Cancer Observatory 2020 for 185 countries was used to estimate current cervical cancer incidence and mortality and their associations with predictors by linear regression analysis. Estimated age-standardized rates (ASR) and average annual percentage changes (AAPC) from cancer registries for up to 53 countries through 2018 were used for trend analysis by joinpoint regression. RESULTS: Wide variations in cervical cancer were observed globally with the highest rates of incidence and mortality in East Africa (ASR, 40.1 and 28.6). The incidence and mortality of cervical cancer were positively associated with human papillomavirus, human immunodeficiency virus infection and negatively associated with cervical cancer screening coverage. In the most recent 5 years, reduction of incidence and mortality was found from 22 (AAPC, -11.2 to -0.5) and 27 countries (-21.5 to -0.3). Increase of incidence and mortality was found from 13 (1.7 to 6.5) and 5 (0.3 to 1.8) countries. Comparing to women aged above 50 years, increasing incidence were additionally found among women under age 50 years from 9 countries (ranging from 0.2 in Denmark to 3.8 in Sweden). CONCLUSIONS: While most countries with cancer registry have shown reduction in cervical cancer incidence and mortality, the increasing incidence among younger women from some developed countries warrants further implementation of effective cancer screening.


Assuntos
Neoplasias do Colo do Útero/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Efeitos Psicossociais da Doença , Feminino , Saúde Global , Humanos , Incidência , Modelos Lineares , Pessoa de Meia-Idade , Sistema de Registros , Neoplasias do Colo do Útero/mortalidade , Adulto Jovem
10.
Liver Int ; 41(8): 1762-1774, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33590659

RESUMO

AIMS: This study aims to assess the trend of hepatitis B virus (HBV)-attributable liver cancer as well as the impact of HBV vaccine on it. METHODS: We retrieved data from Global Burden Disease study to estimate trends of HBV-attributable liver cancer by region and age from 1990 to 2017 and HBV vaccine data from World Health Organization to assess its impact on these trends for children (0-14 years), adolescents and young adults (15-29 years). Change of cancer cases, age-standardized incidence rate (ASR) and estimated annual percentage change (EAPC) were used to quantify the trends of HBV-attributable liver cancer. RESULTS: In this study, reduction in HBV-attributable cancer incident cases was found among children (from 2080 to 1430), adolescents and young adults (from 10 890 to 9090). In terms of ASR, overall reduction was observed globally by an average of -0.45% (95% CI: -0.62 to -0.29) per year in the same period. The highest reduction in ASR was found in adolescents and young adults with EAPC of -3.02 (95% CI: -3.57 to -2.46). Although the ASR has decreased from all the five regions with universal HBV immunization programme, it has increased in the region without universal vaccination and the highest increase was found among children with EAPC of 1.97 (95% CI: 1.71-2.23). CONCLUSION: Significant reduction in HBV-attributable liver cancer among children was mainly because of the universal HBV vaccination. However, the increasing trend of HBV-attributable liver cancer in region without universal HBV vaccination suggested the necessity of introducing universal immunization.


Assuntos
Hepatite B , Neoplasias Hepáticas , Adolescente , Criança , Pré-Escolar , Carga Global da Doença , Hepatite B/complicações , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Vacinas contra Hepatite B , Vírus da Hepatite B , Humanos , Lactente , Recém-Nascido , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/prevenção & controle , Vacinação , Adulto Jovem
11.
Clin Infect Dis ; 71(2): 340-350, 2020 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31504309

RESUMO

BACKGROUND: Despite recommendations that older adults receive acellular pertussis vaccines, data on direct effectiveness in adults aged over 50 years are sparse. METHODS: A case-control study nested within an adult cohort. Cases were identified from linked pertussis notifications and each matched to 3 controls on age, sex, and cohort recruitment date. Cases and controls were invited to complete a questionnaire, with verification of vaccination status by their primary care provider. Vaccine effectiveness (VE) was estimated by conditional logistic regression, with adjustment for reported contact with children and area of residence. RESULTS: Of 1112 notified cases in the cohort, we had complete data for 333 cases and 506 controls. Among 172 PCR-diagnosed cases (mean age, 61 years), 11.2% versus 19.5% of controls had provider-verified pertussis vaccination, on average, 3.2 years earlier. Adjusted VE against PCR-diagnosed pertussis was 52% (95% CI, 15-73%), nonsignificantly higher if vaccinated within 2 years (63%; -5-87%). Adjusted VE was similar in adults born before 1950, presumed primed by natural infection (51%; -8-77%) versus those born 1950 or later who may have received whole-cell pertussis vaccine (53%; -11-80%) (P-heterogeneity = 0.9). Among 156 cases identified by single-point serology, adjusted VE was -55% (-177-13%). CONCLUSIONS: We found modest protection against PCR-confirmed pertussis among older adults (mean age, 61 years; range, 46-81 years) within 5 years after acellular vaccine. The most likely explanation for the markedly divergent VE estimate from cases identified by single-titer serology is misclassification arising from limited diagnostic specificity in our setting.


Assuntos
Vacinas contra Difteria, Tétano e Coqueluche Acelular , Coqueluche , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Criança , Humanos , Pessoa de Meia-Idade , Vacina contra Coqueluche , Vacinação , Vacinas Acelulares , Coqueluche/epidemiologia , Coqueluche/prevenção & controle
12.
J Viral Hepat ; 27(1): 74-80, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31498941

RESUMO

Routine antenatal screening for chronic hepatitis B (HBV) in countries with high migrant populations provides an opportunity to monitor trends in HBV prevalence and can inform estimates locally and in countries with limited seroprevalence data. We linked perinatal birth register records with HBV notifications in the largest Australian state, over the period 2000-2016. Among women aged 15-44 years, we estimated age-standardized chronic HBV prevalence overall and by country of birth and also estimated trends in age-standardized HBV prevalence over time using regression modelling. Among 903 831 women, 8001 linked to a chronic HBV infection record (overall age-standardized prevalence 0.76%, 95% CI: 0.74-0.78). Prevalence varied by country of birth with the highest estimates among women born in Sierra Leone (11.13%, 95% CI: 8.29-13.96), Taiwan (8.08%, 95% CI: 6.74%-9.43%), Cambodia (7.47%, 95% CI: 6.50%-8.45%) and Vietnam (7.36%, 95% CI: 6.97%-7.75%); more moderate estimates among women from North Korea (2.76%, 95% CI: 1.99-3.53) and Samoa (2.64%, 95% CI: 1.99%-3.29%); prevalence was 0.18% (95% CI: 0.17-0.19) in Australian-born women. Over 17 years, there were significant reductions in HBV prevalence among all women (from 0.88% in 2000 to 0.57% in 2016; P < .0001). Among women from high prevalence countries, the greatest absolute reductions were observed among those from Taiwan (10.1%, P < .001) followed by Tonga (5.4%, P < .001), whereas no reductions were observed for women born in Vietnam (P = .08), South Korea (P = .41) and Sudan (P = .06). In conclusion, routine antenatal HBV testing can be used to inform HBV prevalence estimates and vaccine programme impact in countries with limited surveillance and high migration to Australia.


Assuntos
Emigrantes e Imigrantes , Hepatite B Crônica/etnologia , Sistema de Registros , Adolescente , Adulto , Austrália/epidemiologia , Feminino , Humanos , Gravidez , Complicações Infecciosas na Gravidez/etnologia , Prevalência , Estudos Soroepidemiológicos , Adulto Jovem
13.
Proc Natl Acad Sci U S A ; 113(2): E191-200, 2016 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-26715754

RESUMO

Understanding how malaria parasites gain entry into human red blood cells is essential for developing strategies to stop blood stage infection. Plasmodium vivax preferentially invades reticulocytes, which are immature red blood cells. The organism has two erythrocyte-binding protein families: namely, the Duffy-binding protein (PvDBP) and the reticulocyte-binding protein (PvRBP) families. Several members of the PvRBP family bind reticulocytes, specifically suggesting a role in mediating host cell selectivity of P. vivax. Here, we present, to our knowledge, the first high-resolution crystal structure of an erythrocyte-binding domain from PvRBP2a, solved at 2.12 Å resolution. The monomeric molecule consists of 10 α-helices and one short ß-hairpin, and, although the structural fold is similar to that of PfRh5--the essential invasion ligand in Plasmodium falciparum--its surface properties are distinct and provide a possible mechanism for recognition of alternate receptors. Sequence alignments of the crystallized fragment of PvRBP2a with other PvRBPs highlight the conserved placement of disulfide bonds. PvRBP2a binds mature red blood cells through recognition of an erythrocyte receptor that is neuraminidase- and chymotrypsin-resistant but trypsin-sensitive. By examining the patterns of sequence diversity within field isolates, we have identified and mapped polymorphic residues to the PvRBP2a structure. Using mutagenesis, we have also defined the critical residues required for erythrocyte binding. Characterization of the structural features that govern functional erythrocyte binding for the PvRBP family provides a framework for generating new tools that block P. vivax blood stage infection.


Assuntos
Sequência Conservada , Eritrócitos/metabolismo , Plasmodium vivax/metabolismo , Proteínas de Protozoários/química , Proteínas de Protozoários/metabolismo , Sequência de Aminoácidos , Área Sob a Curva , Sequência de Bases , Cristalografia por Raios X , Evolução Molecular , Frequência do Gene , Genes de Protozoários , Haplótipos , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Plasmodium falciparum/genética , Plasmodium falciparum/metabolismo , Plasmodium vivax/genética , Polimorfismo de Nucleotídeo Único/genética , Estrutura Terciária de Proteína , Proteínas de Protozoários/genética , Espalhamento a Baixo Ângulo , Alinhamento de Sequência
16.
J Neurooncol ; 125(1): 79-89, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26297046

RESUMO

There are some evidences that pituitary tumors may be sensitive to the anti-proliferative effects of mammalian target of rapamycin (mTOR) inhibitors, while the mechanism and effects remains unclear, it is necessary to find if a specific mTOR inhibition, including the blocking of both mTOR function and expression, generate any effects on pituitary adenoma cells. The object of this study was to examine if specific inhibition of mTOR induced anti-proliferative effect and decreased the GH and PRL hormones secretion in GH3 and MtT/E pituitary adenoma cells by using a kind of mTOR shRNA lentiviral vector. The in vitro experiments results showed mTOR shRNA transfection robustly reduced the GH3 and MtT/E cells viability in all durations (1-6 days) we performed, also specifically decreased both GH and PRL hormones external secretion in GH3 cells. Further results suggested that specific inhibition of mTOR decreased the hormones secretion through anti-proliferation effects on GH3 cells and reducing the hormones synthesis, but not through affecting the process of hormones secretion. Then we used phosphatidic acid (PA), a kind of mTOR activator, to promote the cell proliferation and GH and PRL hormones secretion in GH3 cells while the effects were blocked by mTOR shRNA transfection. In addition, we examined in vitro effects of PA treatment and mTOR shRNA gene transfection on major proteins expressed in the mTOR pathway in GH3 cells, and confirmed that PA treatment significant increased the protein levels of pmTOR, pS6 K and p4EBP1 in the scramble shRNA group, while the increase of protein levels was blocked by mTOR shRNA gene transfection. Moreover, mTOR shRNA gene transfection definitely inhibited the expression of mTOR and reduced the expression of pmTOR, pS6K and p4EBP1 in either PA or no PA treatment groups. These findings indicated that specific inhibition of mTOR pathway induced anti-proliferative effect and decreased the GH and PRL hormones secretion in cultured pituitary adenoma cells, which may be a novel promising and potential treatment modality for patients with secreting or non-secreting pituitary adenomas.


Assuntos
Proliferação de Células/fisiologia , Hormônio do Crescimento/metabolismo , Prolactina/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Análise de Variância , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Ensaio de Imunoadsorção Enzimática , Humanos , Ácidos Fosfatídicos/farmacologia , Neoplasias Hipofisárias/patologia , RNA Interferente Pequeno/genética , Ratos , Proteínas Quinases S6 Ribossômicas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/genética , Fatores de Tempo , Transfecção
17.
PLoS One ; 19(4): e0299924, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38635814

RESUMO

BACKGROUND: While the 23-valent pneumococcal polysaccharide vaccine (PPV23) has demonstrated its role in preventing severe pneumococcal disease, its impact on more non-specific conditions like acute respiratory tract infection (ARI) and lower respiratory tract infections (LRTI) remains unclear. We aimed to investigate the role of PPV23 in prevention of presentations for ARI and LRTI and related antibiotic prescriptions among older adults in primary care. METHODS: Using a nationwide general practice dataset, we followed a cohort of regularly attending patients aged ≥65 years from 1 January 2014 until 31 December 2018 for presentations for ARI, LRTI, and related antibiotic prescriptions. Associations between PPV23 receipt and each outcome were assessed using a multiple failures survival model to estimate hazard ratios (HR) adjusted for age, sex, socioeconomic status, and various health measures. RESULTS: A cohort of 75,264 patients aged ≥65 years (mean 75.4, 56% female) in 2014 was followed. The incidence of presentations for ARI, ARI-related antibiotic prescription, LRTI, and LRTI-related antibiotic prescription was 157.6, 76.0, 49.6, and 24.3 per 1000 person-years, respectively. Recent PPV23 vaccine receipt was associated with a small reduction in ARI presentations (adjusted HR vaccinated vs. unvaccinated 0.96; 95%CI 0.94-0.98; p = 0.002); however, there was no reduction in ARI-related antibiotic prescription, LRTI presentation, nor LRTI-related antibiotic prescription (adjusted HR were 0.99[95%CI 0.96-1.03], 1.04[95%CI 0.99-1.09], 1.07[95%CI 1.00-1.14]). CONCLUSION: PPV23 vaccination in older adults may result in a small reduction in the incidence of total ARI presentations in primary care. However, the effect is small and residual confounding cannot be excluded.


Assuntos
Infecções Pneumocócicas , Infecções Respiratórias , Humanos , Feminino , Idoso , Masculino , Antibacterianos/uso terapêutico , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/prevenção & controle , Streptococcus pneumoniae , Vacinação , Vacinas Pneumocócicas/uso terapêutico , Atenção Primária à Saúde , Infecções Pneumocócicas/tratamento farmacológico , Infecções Pneumocócicas/prevenção & controle
18.
AIDS ; 38(6): 803-812, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38578958

RESUMO

OBJECTIVES: There is conflicting data regarding the response of older people with HIV (PWH) to antiretroviral therapy (ART). The objective of this study was to evaluate the long-term immunological and virological responses, changes in regimen, and adverse drug reactions (ADRs) in older participants (50+ years) compared with younger (18-34 years) and middle-aged (35-49 years) PWH. METHODS: A retrospective review of medical records was conducted on 1622 participants who received ART in Yunnan Province, China, from 2010 to 2019. The study compared CD4+ T-cell counts, CD4+/CD8+ ratio, and relative numbers between different groups using the Kruskal-Wallis test. Cox proportional hazards regression models were used to identify variables associated with the occurrence of immune reconstitution insufficiency. The rates of immune reconstitution, incidence of ADRs, and rates of treatment change were analyzed using the chi-squared test or Fisher's exact test. RESULTS: Over 95% achieved viral load 200 copies/ml or less, with no age-related difference. However, older participants exhibited significantly lower CD4+ T-cell counts and CD4+/CD8+ recovery post-ART (P < 0.001), with only 32.21% achieving immune reconstitution (compared with young: 52.16%, middle-aged: 39.29%, P < 0.001) at the end of follow-up. Middle-aged and elderly participants changed ART regimens more because of ADRs, especially bone marrow suppression and renal dysfunction. CONCLUSION: Although the virological response was consistent across age groups, older individuals showed poorer immune responses and higher susceptibility to side effects. This underscores the need for tailored interventions and comprehensive management for older patients with HIV.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Pessoa de Meia-Idade , Idoso , Humanos , Infecções por HIV/tratamento farmacológico , Fármacos Anti-HIV/efeitos adversos , China , Resultado do Tratamento , Contagem de Linfócito CD4 , Carga Viral
19.
Infect Control Hosp Epidemiol ; 44(5): 755-761, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35795915

RESUMO

OBJECTIVES: To determine the association between after-hours consultations and the likelihood of antibiotic prescribing for self-limiting upper respiratory tract infections (URTIs) in primary care practices. DESIGN: A cross-sectional analysis using Australian national primary-care practice data (MedicineInsight) between February 1, 2016 and January 31, 2019. SETTING: Nationwide primary-care practices across Australia. PARTICIPANTS: Adult and pediatric patients who visited primary care practices for first-time URTIs. METHODS: We estimated the proportion of first-time URTI episodes for which antibiotic prescribing occurred on the same day (immediate prescribing) using diagnoses and prescription records in the electronic primary-care database. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for the likelihood of antibiotic prescribing by the time of primary care visits were calculated using generalized estimating equations. RESULTS: Among 357,287 URTI episodes, antibiotics were prescribed in 172,605 episodes (48.3%). After adjusting for patients' demographics, practice characteristics, and seasons, we detected a higher likelihood of antibiotic prescribing on weekends compared to weekdays (OR, 1.42; 95% CI, 1.39-1.45) and on national public holidays compared to nonholidays (OR, 1.23; 95% CI, 1.17-1.29). When we controlled for patient presentation and diagnosis, the association between antibiotic prescribing and after-hours consultations remained significant: weekend versus weekdays (OR, 1.37; 95% CI, 1.33-1.41) and holidays versus nonholidays (OR, 1.10; 95% CI, 1.03-1.18). CONCLUSIONS: Primary-care consultations on weekends and public holidays were associated with a higher likelihood of immediate antibiotic prescribing for self-limiting URTIs in primary care. This finding might be attributed to lower resourcing in after-hours health care.


Assuntos
Antibacterianos , Infecções Respiratórias , Adulto , Humanos , Criança , Antibacterianos/uso terapêutico , Estudos Transversais , Austrália , Infecções Respiratórias/tratamento farmacológico , Padrões de Prática Médica , Encaminhamento e Consulta , Prescrição Inadequada
20.
Vaccine ; 41(43): 6522-6529, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37741762

RESUMO

BACKGROUND: Respiratory infections including influenza and pertussis are associated with significant morbidity and mortality in mothers and newborns. Vaccination during pregnancy against influenza and pertussis is recommended for all women but data on uptake in Australia is limited. METHODS: We conducted a retrospective population-based cohort study in Australia's largest state, New South Wales (NSW), using a Perinatal Data Collection (PDC). Data included demographic, pregnancy, and birth details including pertussis and influenza vaccination during pregnancy for all women giving birth between 01 January 2016 and 31 December 2020. We used descriptive statistics to assess uptake of influenza and pertussis vaccination during pregnancy and Poisson loglinear regression to estimate associations between maternal characteristics and vaccine receipt. RESULTS: During 2016-2020, there were 477,776 births (mean maternal age 32.25 years). In 176,255 (36.9%) births the mother received both vaccines; 202,922 (42.5%) influenza and 315,620 (66.1%) pertussis vaccine. From 2016 to 2020, reported coverage increased from 26.7% to 58.7% for influenza and 43.1% to 78.8% for pertussis, respectively. After adjustment, characteristics associated with lower likelihood of receiving influenza and pertussis vaccination included: younger age (<30 years), being born in Australia/New Zealand, from lower socio-economic strata, having previous pregnancies, being later to first antenatal care, utilising the public hospital care model, smoking, having chronic hypertension and BMI > 25 kg/m2. CONCLUSIONS: While reported coverage of both influenza and pertussis vaccine in birthing women in NSW has increased over time, disparities in coverage exist and they highlight areas where evidence-based interventions to improve maternal vaccination could be targeted.

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