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1.
J Immunol ; 209(8): 1499-1512, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-36165172

RESUMO

Phagocytic responses by effector cells to opsonized viruses have been recognized to play a key role in antiviral immunity. Limited data on coronavirus disease 2019 suggest that the role of Ab-dependent and -independent phagocytosis may contribute to the observed immunological and inflammatory responses; however, their development, duration, and role remain to be fully elucidated. In this study of 62 acute and convalescent patients, we found that patients with acute coronavirus disease 2019 can mount a phagocytic response to autologous plasma-opsonized Spike protein-coated microbeads as early as 10 d after symptom onset, while heat inactivation of this plasma caused 77-95% abrogation of the phagocytic response and preblocking of Fc receptors showed variable 18-60% inhibition. In convalescent patients, phagocytic response significantly correlated with anti-Spike IgG titers and older patients, while patients with severe disease had significantly higher phagocytosis and neutralization functions compared with patients with asymptomatic, mild, or moderate disease. A longitudinal subset of the convalescent patients over 12 mo showed an increase in plasma Ab affinity toward Spike Ag and preservation of phagocytic and neutralization functions, despite a decline in the anti-Spike IgG titers by >90%. Our data suggest that early phagocytosis is primarily driven by heat-liable components of the plasma, such as activated complements, while anti-Spike IgG titers account for the majority of observed phagocytosis at convalescence. Longitudinally, a significant increase in the affinity of the anti-Spike Abs was observed that correlated with the maintenance of both the phagocytic and neutralization functions, suggesting an improvement in the quality of the Abs.


Assuntos
COVID-19 , Anticorpos Neutralizantes , Anticorpos Antivirais , Antivirais , Humanos , Imunoglobulina G , Receptores Fc , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus
2.
Immunol Cell Biol ; 101(2): 142-155, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36353774

RESUMO

The long-term health consequences of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are still being understood. The molecular and phenotypic properties of SARS-CoV-2 antigen-specific T cells suggest a dysfunctional profile that persists in convalescence in those who were severely ill. By contrast, the antigen-specific memory B-cell (MBC) population has not yet been analyzed to the same degree, but phenotypic analysis suggests differences following recovery from mild or severe coronavirus disease 2019 (COVID-19). Here, we performed single-cell molecular analysis of the SARS-CoV-2 receptor-binding domain (RBD)-specific MBC population in three patients after severe COVID-19 and four patients after mild/moderate COVID-19. We analyzed the transcriptomic and B-cell receptor repertoire profiles at ~2 months and ~4 months after symptom onset. Transcriptomic analysis revealed a higher level of tumor necrosis factor-alpha (TNF-α) signaling via nuclear factor-kappa B in the severe group, involving CD80, FOS, CD83 and TNFAIP3 genes that was maintained over time. We demonstrated the presence of two distinct activated MBCs subsets based on expression of CD80hi TNFAIP3hi and CD11chi CD95hi at the transcriptome level. Both groups revealed an increase in somatic hypermutation over time, indicating progressive evolution of humoral memory. This study revealed distinct molecular signatures of long-term RBD-specific MBCs in convalescence, indicating that the longevity of these cells may differ depending on acute COVID-19 severity.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Células B de Memória , Convalescença , Anticorpos Antivirais
3.
J Med Virol ; 95(1): e28198, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36207770

RESUMO

The aim of this study was to evaluate the role of viral polymerase chain reaction (PCR) testing in patients with aseptic meningitis and identify opportunities for improvement in clinical management. All cerebrospinal fluid samples collected in 1 year from four teaching hospitals in Sydney, Australia, were reviewed. Patients with aseptic meningitis were selected, and clinical and diagnostic features, hospital length of stay (LOS), and treatment were analyzed. Identifying a cause by viral PCR did not reduce hospital LOS (median 3 days) or antibiotic use (median 2 days), but the turnaround time of the PCR test correlated with LOS (Rs = 0.3822, p = 0.0003). Forty-one percent of patients received intravenous acyclovir treatment, which was more frequent in patients admitted under neurologists than infectious diseases physicians (56% vs. 24%; p = 0.013). The majority of patients did not have investigations for alternative causes of aseptic meningitis such as human immunodeficiency virus and syphilis if the viral PCR panel was negative. The benefit of PCR testing in aseptic meningitis in adults in reducing LOS and antibiotic use is unclear. The reasons for unnecessary aciclovir use in meningitis syndromes require further assessment.


Assuntos
Infecções por Enterovirus , Enterovirus , Meningite Asséptica , Meningite Viral , Humanos , Adulto , Lactente , Estudos Retrospectivos , Meningite Asséptica/diagnóstico , Meningite Asséptica/tratamento farmacológico , Meningite Asséptica/líquido cefalorraquidiano , Enterovirus/genética , Reação em Cadeia da Polimerase , Meningite Viral/diagnóstico , Meningite Viral/tratamento farmacológico , Meningite Viral/líquido cefalorraquidiano , Antibacterianos/uso terapêutico , Aciclovir/uso terapêutico , Líquido Cefalorraquidiano
4.
Intern Med J ; 53(12): 2298-2306, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36951401

RESUMO

BACKGROUND: Bacterial meningitis is a medical emergency and timely management has been shown to improve outcomes. The aim of this study was to compare the early assessment and management of adults with suspected community-onset meningitis between hospitals and identify opportunities for clinical practice improvement. METHODS: This retrospective cohort study was conducted at three principal referral hospitals in Sydney, Australia. Adult patients with suspected meningitis undergoing cerebrospinal fluid sampling between 1 July 2018 and 31 June 2019 were included. Relevant clinical and laboratory data were extracted from the medical record. Differences between sites were analysed and factors associated with time to antimicrobial therapy were assessed by Cox regression. RESULTS: In 260 patients, the median time from triage to antibiotic administration was 332 min with a difference of up to 147 min between hospitals. Median time from triage to lumbar puncture (LP) was 366 min with an inter-hospital difference of up to 198 min. Seventy per cent of patients had neuroimaging prior to LP, and this group had a significantly longer median time to antibiotic administration (367 vs 231 min; P = 0.001). Guideline concordant antibiotics were administered in 84% of patients, with only 39% of those administered adjunctive corticosteroids. Seven (3%) patients had confirmed bacterial meningitis. Modifiable factors associated with earlier antimicrobial administration included infectious diseases involvement (adjusted hazard ratio [aHR], 1.50 [95% confidence interval (CI), 1.01-2.24]) and computed tomography (CT) scanning (aHR, 0.67 [95% CI, 0.46-0.98]). CONCLUSION: Opportunities for improvement include reducing the time to LP and antibiotic administration, improving coadministration of corticosteroids and avoiding potentially unnecessary CT scanning.


Assuntos
Meningites Bacterianas , Adulto , Humanos , Estudos Retrospectivos , Meningites Bacterianas/diagnóstico , Meningites Bacterianas/tratamento farmacológico , Meningites Bacterianas/líquido cefalorraquidiano , Antibacterianos/uso terapêutico , Punção Espinal , Corticosteroides/uso terapêutico
5.
Med J Aust ; 216(1): 39-42, 2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-34633100

RESUMO

OBJECTIVE: To estimate the numbers of COVID-19-related hospitalisations in Australia after re-opening the international border. DESIGN: Population-level deterministic compartmental epidemic modelling of eight scenarios applying various assumptions regarding SARS-CoV-2 transmissibility (baseline R0 = 3.5 or 7.0), vaccine rollout speed (slow or fast), and scale of border re-opening (mean of 2500 or 13 000 overseas arrivals per day). SETTING: Simulation population size, age structure, and age-based contact rates based on recent estimates for the Australian population. We assumed that 80% vaccination coverage of people aged 16 years or more was reached in mid-October 2021 (fast rollout) or early January 2022 (slow rollout). MAIN OUTCOME MEASURES: Numbers of people admitted to hospital with COVID-19, December 2021 - December 2022. RESULTS: In scenarios assuming a highly transmissible SARS-CoV-2 variant (R0  = 7.0), opening the international border on either scale was followed by surges in both infections and hospitalisations that would require public health measures beyond mask wearing and social distancing to avoid overwhelming the health system. Reducing the number of hospitalisations to manageable levels required several cycles of additional social and mobility restrictions. CONCLUSIONS: If highly transmissible SARS-CoV-2 variants are circulating locally or overseas, large and disruptive COVID-19 outbreaks will still be possible in Australia after 80% of people aged 16 years or more have been vaccinated. Continuing public health measures to restrict the spread of disease are likely to be necessary throughout 2022.


Assuntos
COVID-19/epidemiologia , Controle de Doenças Transmissíveis/estatística & dados numéricos , Doenças Transmissíveis Importadas/epidemiologia , Surtos de Doenças , Hospitalização/estatística & dados numéricos , Adolescente , Adulto , Idoso , Austrália/epidemiologia , COVID-19/prevenção & controle , COVID-19/virologia , Controle de Doenças Transmissíveis/métodos , Doenças Transmissíveis Importadas/virologia , Simulação por Computador , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Cobertura Vacinal/estatística & dados numéricos , Adulto Jovem
6.
J Environ Sci (China) ; 122: 217-226, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35717086

RESUMO

Hausmannite is a common low valence Mn oxide mineral, with a distorted spinel structure, in surficial sediments. Although natural Mn oxides often contain various impurities of transitional metals (TMs), few studies have addressed the effect and related mechanism of TM doping on the reactivity of hausmannite with metal pollutants. Here, the reactivity of cobalt (Co) doped hausmannite with aqueous As(III) and As(V) was studied. Co doping decreased the point of zero charge of hausmannite and its adsorption capacity for As(V). Despite a reduction of the initial As(III) oxidation rate, Co-doped hausmannite could effectively oxidize As(III) to As(V), followed by the adsorption and fixation of a large amount of As(V) on the mineral surface. Arsenic K-edge EXAFS analysis of the samples after As(V) adsorption and As(III) oxidation revealed that only As(V) was adsorbed on the mineral surface, with an average As-Mn distance of 3.25-3.30 Å, indicating the formation of bidentate binuclear complexes. These results provide new insights into the interaction mechanism between TMs and low valence Mn oxides and their effect on the geochemical behaviors of metal pollutants.


Assuntos
Arsênio , Poluentes Ambientais , Adsorção , Arsênio/química , Cobalto/química , Compostos de Manganês/química , Minerais , Oxirredução , Óxidos/química
7.
BMC Infect Dis ; 21(1): 321, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33827458

RESUMO

BACKGROUND: Influenza is a highly contagious respiratory virus with clinical impacts on patient morbidity, mortality and hospital bed management. The effect of rapid nucleic acid testing (RPCR) in comparison to standard multiplex PCR (MPCR) diagnosis in treatment decisions is unclear. This study aimed to determine whether RPCR influenza testing in comparison to standard MPCR testing was associated with differences in antibiotic and antiviral (oseltamivir) utilisation and hospital length of stay in emergency department and inpatient hospital settings. METHODS: A retrospective cohort study of positive influenza RPCR and MPCR patients was performed utilising data from the 2017 influenza season. Medical records of correlating patient presentations were reviewed for data collection. An analysis of RPCR versus MPCR patient outcomes was performed examining test turnaround time, antibiotic initiation, oseltamivir initiation and hospital length of stay for both emergency department and inpatient hospital stay. Subgroup analysis was performed to assess oseltamivir use in high risk populations for influenza complications. Statistical significance was assessed using Mann-Whitney test for numerical data and Chi-squared test for categorical data. Odds ratio with 95% confidence intervals were calculated where appropriate. RESULTS: Overall, 122 RPCR and 362 MPCR positive influenza patients were included in this study. Commencement of antibiotics was less frequent in the RPCR than MPCR cohorts (51% vs 67%; p < 0.01, OR 0.52; 95% CI 0.34-0.79). People at high risk of complications from influenza who were tested with the RPCR were more likely to be treated with oseltamivir compared to those tested with the MPCR (76% vs 63%; p = 0.03, OR 1.81; 95% CI 1.07-3.08). Hospital length of stay was not impacted when either test was used in the emergency department and inpatient settings. CONCLUSIONS: These findings suggest utilisation of RPCR testing in influenza management can improve antibiotic stewardship through reduction in antibiotic use and improvement in oseltamivir initiation in those at higher risk of complications. Further research is required to determine other factors that may have influenced hospital length of stay and a cost-benefit analysis should be undertaken to determine the financial impact of the RPCR test.


Assuntos
Antibacterianos/uso terapêutico , Antivirais/uso terapêutico , Influenza Humana/diagnóstico , Influenza Humana/tratamento farmacológico , Reação em Cadeia da Polimerase Multiplex , Adulto , Idoso , Idoso de 80 Anos ou mais , Gestão de Antimicrobianos , Serviço Hospitalar de Emergência , Feminino , Humanos , Pacientes Internados , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Oseltamivir/uso terapêutico , Estudos Retrospectivos
8.
BMC Med Inform Decis Mak ; 21(1): 168, 2021 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-34022851

RESUMO

BACKGROUND: Assessing the accuracy of diagnostic coding is essential to ensure the validity and reliability of administrative coded data. The aim of the study was to evaluate the accuracy of assigned International Classification of Diseases version 10-Australian Modification (ICD-10-AM) codes for influenza by comparing with patients' results of their polymerase chain reaction (PCR)-based laboratory tests. METHOD: A retrospective study was conducted across seven public hospitals in New South Wales, Australia. A total of 16,439 patients who were admitted and tested by either cartridge-based rapid PCR or batched multiplex PCR between January 2016 and December 2017 met the inclusion criteria. We calculated the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of ICD-10-AM coding using laboratory results as a gold standard. Separate analyses were conducted to determine whether the availability of test results at the time of hospital discharge influenced diagnostic coding accuracy. RESULTS: Laboratory results revealed 2759 positive influenza cases, while ICD-10-AM coding identified 2527 patients. Overall, 13.7% (n = 378) of test positive patients were not assigned an ICD-10-AM code for influenza. A further 5.8% (n = 146) patients with negative test results were incorrectly assigned an ICD-10-AM code for influenza. The sensitivity, specificity, PPV and NPV of ICD-10-AM coding were 93.1%; 98.9%; 94.5% and 98.6% respectively when test results were received before discharge and 32.7%; 99.2%; 87.8% and 89.8% respectively when test results were not available at discharge. The sensitivity of ICD-10-AM coding varied significantly across hospitals. The use of rapid PCR or hospitalisation during the influenza season were associated with greater coding accuracy. CONCLUSION: Although ICD-10-AM coding for influenza demonstrated high accuracy when laboratory results were received before discharge, its sensitivity was substantially lower for patients whose test results were not available at discharge. The timely availability of laboratory test results during the episode of care could contribute to improved coding accuracy.


Assuntos
Influenza Humana , Alta do Paciente , Austrália , Codificação Clínica , Hospitais , Humanos , Influenza Humana/diagnóstico , Classificação Internacional de Doenças , Laboratórios , New South Wales , Reprodutibilidade dos Testes , Estudos Retrospectivos
9.
Asian Pac J Allergy Immunol ; 39(2): 124-128, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31175715

RESUMO

BACKGROUND: Antibiotic allergy labels have a direct impact on individual patient care and on the consumption of broad-spectrum antibiotics. OBJECTIVE: Our aim was to establish the prevalence of antibiotic allergies and to determine whether patients with documented antibiotic allergy labels received guideline concordant antimicrobial therapy. Additionally we wanted to evaluate the quality of allergy documentation in the medical record. METHODS: Prospective audit of all patients presenting to the Emergency Department of an adult teaching hospital in Sydney over a 4 month period. Documented allergy labels, diagnoses, antibiotic administration and outcomes were recorded. Appropriateness of antibiotic choice was based on the Australian National Antimicrobial Prescribing Survey. RESULTS: 9.9% of presentations had at least one antibiotic allergy recorded. Significantly more women than men had antibiotic allergies documented. One third of patients with documented antibiotic allergies were prescibed inappropriate antibiotic therapy and some had significant adverse events. CONCLUSIONS: The documentation of antibiotic allergy labels and choice of antibiotic treatment can be significantly improved. Strategies to safely de-label people with documented allergies who are not truly allergic need to be implemented.


Assuntos
Hipersensibilidade a Drogas , Adulto , Antibacterianos/efeitos adversos , Austrália/epidemiologia , Hipersensibilidade a Drogas/diagnóstico , Hipersensibilidade a Drogas/epidemiologia , Hipersensibilidade a Drogas/etiologia , Serviço Hospitalar de Emergência , Feminino , Hospitais de Ensino , Humanos , Masculino , Prevalência , Estudos Retrospectivos
10.
Clin Infect Dis ; 71(6): 1502-1510, 2020 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-31585005

RESUMO

BACKGROUND: Microelimination of hepatitis C virus (HCV) among people living with human immunodeficiency virus (HIV) may be feasible in Australia, given unrestricted access to direct-acting antiviral (DAA) therapy from 2016. Our aim was to evaluate progress towards elimination goals within HIV/HCV-coinfected adults in Australia following universal DAA access. METHODS: The CEASE prospective cohort study enrolled adults with HIV/HCV, irrespective of viremic status, from 14 primary and tertiary clinics in Australia. Annual and cumulative HCV treatment uptake, outcome, and HCV RNA prevalence were evaluated, with follow-up through May 2018 (median follow-up, 2.63 years). Factors associated with DAA uptake were analyzed. RESULTS: Between July 2014 and March 2017, 402 participants who were HIV/HCV antibody positive were enrolled (95% male [80% gay and bisexual men,], 13% cirrhosis, 80% history of injecting drug use [39% currently injecting]). Following universal DAA access, annual HCV treatment uptake in those eligible increased from 7% and 11% per year in 2014 and 2015, respectively, to 80% in 2016. By 2018, cumulative HCV treatment uptake in those ever eligible for treatment was 91% (336/371). HCV viremic prevalence declined from 82% (95% CI, 78-86%) in 2014 to 8% (95% CI, 6-12%) in 2018. Reinfection was reported in only 5 participants for a reinfection incidence of 0.81 per 100 person-years (95% CI, 0.34-1.94). CONCLUSIONS: High uptake and effectiveness of unrestricted DAA therapy in Australia have permitted rapid treatment scale-up, with a dramatic reduction in HCV infection burden and low reinfection rate among people living with HIV, suggesting that microelimination is feasible. CLINICAL TRIALS REGISTRATION: NCT02102451.


Assuntos
Infecções por HIV , Hepatite C Crônica , Hepatite C , Adulto , Antivirais/uso terapêutico , Austrália/epidemiologia , Feminino , HIV , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Hepacivirus , Hepatite C/tratamento farmacológico , Hepatite C/epidemiologia , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/epidemiologia , Humanos , Masculino , Estudos Prospectivos
11.
Sex Health ; 17(4): 330-336, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32687780

RESUMO

Background The rapid plasma reagin (RPR) assay is commonly used as a surrogate marker of infectious syphilis, but is non-specific, slow to change and variable in its rate of decline post treatment. METHODS: Within an urban sexual health service testing predominantly men who have sex with men, a file review of RPR changes was undertaken in all subjects who had a dilution level of ≥1:4, between January 2015 to the end of December 2018. RESULTS: Overall, 248 cases of infectious syphilis were identified in 215 subjects (165 HIV seropositive, 50 HIV seronegative). Among unique-subject cases with follow-up RPR recorded, seroreversion to a non-reactive titre was achieved in only 42.3% (71/168) cases at a median of 235 days (interquartile range: 138-348 days) and was significantly less likely if patients had HIV infection (P = 0.02), late latent syphilis (P = 0.003) or a subsequent syphilis infection (P < 0.0001). Having HIV infection (P = 0.03) or a subsequent episode of syphilis (P = 0.01) were associated with a lower likelihood of documented cure. CONCLUSIONS: The slow decay in RPR titres post therapy and the inability of a significant number of subjects to achieve a non-reactive result over time makes RPR a poor test for assessing the adequacy of treatment or in diagnosing re-infection, especially in populations having repeated and frequent risk exposures. As the number of syphilis cases continue to climb, better tests that accurately assess pathogen presence are urgently needed.


Assuntos
Reaginas/sangue , Reinfecção/sangue , Reinfecção/diagnóstico , Sorodiagnóstico da Sífilis/métodos , Sorodiagnóstico da Sífilis/normas , Sífilis/sangue , Sífilis/diagnóstico , Adulto , Fibrinolisina , Homossexualidade Masculina , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , New South Wales/epidemiologia , Estudos Retrospectivos
12.
Australas Psychiatry ; 28(2): 186-189, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32019350

RESUMO

OBJECTIVE: Patients with a severe mental illness have higher rates of infection with blood-borne viruses (BBVs) but are less likely to access testing and treatment. Enhanced testing of this population is therefore warranted. METHODS: In this single centre, prospective study, we sought to offer testing for BBVs to all patients who attended an appointment in the clozapine clinic (CC) over a six-month period. Those who consented were tested for HIV antigen/antibody, hepatitis C virus (HCV) antibody and hepatitis B virus surface antigen (HBsAg). RESULTS: During the study period, 192 patients attended an appointment, of which 164 were offered testing. Of those, 134 (81.7%) accepted and 30 declined. Among patients who agreed to be tested, results were returned for 96 (71.6%). There were no positive results for HBsAg or HIV. Seven patients (7.2%) were positive for HCV antibody. Of those, three were newly identified exposures of which two were found to be chronically infected and were referred for treatment. CONCLUSION: A routine offer of BBV testing for people with severe mental illness in the outpatient setting is feasible and may detect treatable infections.


Assuntos
Infecções por HIV/epidemiologia , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Programas de Rastreamento/estatística & dados numéricos , Transtornos Mentais/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Clozapina/uso terapêutico , Coinfecção/epidemiologia , Feminino , Humanos , Masculino , Transtornos Mentais/tratamento farmacológico , Pessoa de Meia-Idade , New South Wales/epidemiologia , Pacientes Ambulatoriais , Prevalência , Estudos Prospectivos , Adulto Jovem
13.
Environ Sci Technol ; 53(13): 7453-7462, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31150220

RESUMO

Hexagonal birnessite, a typical layered Mn oxide (LMO), can adsorb and oxidize Mn(II) and thereby transform to Mn(III)-rich hexagonal birnessite, triclinic birnessite, or tunneled Mn oxides (TMOs), remarkably changing the environmental behavior of Mn oxides. We have determined the effects of coexisting cations on the transformation by incubating Mn(II)-bearing δ-MnO2 at pH 8 under anoxic conditions for 25 d (dissolved Mn < 11 µM). In the Li+, Na+, and K+ chloride solutions, the Mn(II)-bearing δ-MnO2 first transforms to Mn(III)-rich δ-MnO2 or triclinic birnessite (T-bir) due to the Mn(II)-Mn(IV) comproportionation, most of which eventually transform to a 4 × 4 TMO. In contrast, Mn(III)-rich δ-MnO2 and T-bir form and persist in the Mg2+ and Ca2+ chloride solutions. However, in the presence of surface adsorbed Cu(II), Mn(II)-bearing δ-MnO2 turns into Mn(III)-rich δ-MnO2 without forming T-bir or TMOs. The stabilizing power of the cations on the δ-MnO2 structure positively correlates with their binding strength to δ-MnO2 (Li+, Na+, and K+ < Mg2+ and Ca2+ < Cu(II)). Since metal adsorption decreases the surface energy of minerals, our finding suggests that the surface energy largely controls the thermodynamic stability of LMOs. Our study indicates that the adsorption of divalent metal cations, particularly transition metals, can be an important cause of the high abundance of LMOs, rather than the more stable TMO phases, in the environment.


Assuntos
Compostos de Manganês , Óxidos , Adsorção , Metais , Oxirredução
14.
Sex Health ; 16(3): 282-288, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31167698

RESUMO

Background Women comprise ~10% of people living with HIV in Australia, so are often underrepresented in research. METHODS: This study invited clinicians providing care to women living with HIV to complete an anonymous survey containing questions related to four key areas: HIV (including diagnosis, treatment and virological outcomes), reproductive health (including sexual activity, contraception, pregnancy and outcomes) and linkage and retention in care. RESULTS: In total, 484 surveys were received, with responses from all states and territories. Most women living with HIV in Australia are on treatment (>90%) and virologically suppressed (>90% have a viral load <50 copies mL-1). Almost 75% of women have had at least one switch in treatment (with toxicity almost as common as simplification as the indication). Treatment interruption is also relatively common, but is more likely the longer a woman has been diagnosed, if she is on benefits (P = 0.007) and is the primary carer of children without a partner (P = 0.001). In Australia, women living with HIV are a diverse heterogeneous group, with over 70 different countries of birth and almost half speaking a language other than English at home. Mental health diagnosis was the most common co-morbid condition identified. A total of 21% of women were post-menopausal, with 42% reporting symptoms to their healthcare provider, but only 17% were receiving treatment for symptoms attributed to menopause. CONCLUSIONS: As well as strategies to support women vulnerable to treatment interruption, important areas for future investment in research and clinical care include co-morbid mental health and menopause symptoms and treatment.


Assuntos
Anticoncepção , Substituição de Medicamentos , Infecções por HIV/tratamento farmacológico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Retenção nos Cuidados , Comportamento Sexual , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Austrália/epidemiologia , Comorbidade , Feminino , Infecções por HIV/epidemiologia , Humanos , Transtornos Mentais/epidemiologia , Pessoa de Meia-Idade , Pós-Menopausa , Gravidez , Resultado da Gravidez , Inquéritos e Questionários , Carga Viral , Adulto Jovem
15.
Sex Transm Infect ; 94(3): 187-191, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29021404

RESUMO

OBJECTIVES: The significance of sera with isolated reactive treponemal chemiluminescence immunoassay (IRTCIA) results is unclear. Women have this phenotype more commonly than men. Most cohorts examining this phenotype have included predominantly men and have demonstrated evidence of past or subsequently confirmed syphilis infection in a significant proportion of cases. We hypothesised that a proportion of sera with IRTCIA results would be positive on immunoblot testing and that sera from women with IRTCIA would have different results in immunoblot testing than men. METHODS: IRTCIA sera from a tertiary referral serology laboratory serving multiple clinical sites were analysed with a syphilis line immunoblot assay (LIA) and analysed by sex. Logistic regression was undertaken to assess factors associated with LIA status. Medical record review and descriptive analysis of a separate cohort of women with the IRTCIA phenotype from a single campus was also undertaken. RESULTS: Overall, 19/63 (30.1%) subjects with the IRTCIA phenotype were positive in the LIA, including 13 men and 6 women. Women were significantly less likely to have definitive results (positive or negative) than men (p=0.015). Pregnant women were less likely than non-pregnant women to have a negative LIA result (OR 0.57; p=0.03). Record review of 22 different women with IRTCIA reactivity showed that 2/22 (9.1%) had HIV and previous syphilis infection, 15/22 (68.2%) were pregnant and 3 (13.6%) had autoimmune disease. CONCLUSIONS: A significant proportion of sera with IRTCIA results on serological tests are reactive on LIA testing and some may not be false positive results. The interpretation of IRTCIA results should be undertaken in conjunction with an assessment of factors such as sex, pregnancy, a history of syphilis and other STIs and syphilis risk.


Assuntos
Anticorpos Antibacterianos/imunologia , Immunoblotting , Complicações Infecciosas na Gravidez/imunologia , Sorodiagnóstico da Sífilis , Sífilis/imunologia , Treponema pallidum/isolamento & purificação , Adulto , Idoso , Anticorpos Antibacterianos/sangue , Reações Falso-Positivas , Feminino , Humanos , Medições Luminescentes , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Gravidez , Complicações Infecciosas na Gravidez/sangue , Estudos Retrospectivos , Caracteres Sexuais , Fatores Sexuais , Sífilis/sangue , Sorodiagnóstico da Sífilis/métodos , Adulto Jovem
16.
AIDS Behav ; 22(3): 887-895, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-27995435

RESUMO

An online survey was conducted among people living with HIV (PLHIV) in Australia to discern key factors associated with distinctive ART use patterns. The sample (N = 358), was further divided into three groups: those on ART continuously since initiation (n = 208, 58.1%); those on ART intermittently (n = 117, 32.7%); and those not on ART at the time of survey (n = 33, 9.2%). ART non-users were the most likely to hold serious concerns about ART that outweighed perceived necessities (benefits) from ART (AOR = 0.13; 95% CI 0.06-0.29; p < 0.001). They were also the least self-efficacious in HIV disease management (AOR = 0.29; 95% CI 0.09-0.87; p = 0.028). Intermittent ART users were more likely to receive their HIV diagnosis prior to 2003 (AOR = 0.38; 95% CI 0.28-0.53; p < 0.001) and perceive lower HIV management self-efficacy (AOR = 0.50, 95% CI 0.28-0.87; p = 0.015) than continuous users. ART-related beliefs and perceived self-efficacy in HIV self-management play an important role in achieving universal treatment uptake and sustained high levels of adherence.


Assuntos
Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , Adesão à Medicação , Adulto , Austrália , Feminino , Infecções por HIV/psicologia , Humanos , Masculino , Percepção , Autoeficácia , Inquéritos e Questionários
17.
Infection ; 46(4): 541-548, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29808462

RESUMO

PURPOSE: Surgical antibiotic prophylaxis (SAP) is a common area of antimicrobial misuse. The aim of this study was to explore the social dynamics that influence the use of SAP. METHODS: 20 surgeons and anaesthetists from a tertiary referral hospital in Australia participated in semi-structured interviews focusing on experiences and perspectives on SAP prescribing. Interview data were analysed using the framework approach. RESULTS: Systematic analysis of the participants' account of the social factors influencing SAP revealed four themes. First, antibiotic prophylaxis is treated as a low priority with the competing demands of the operating theatre environment. Second, whilst guidelines have increased in prominence in recent years, there exists a lack of confidence in their ability to protect the surgeon from responsibility for infectious complications (thus driving SAP over-prescribing). Third, non-concordance prolonged duration of SAP is perceived to be driven by benevolence for the individual patient. Finally, improvisation with novel SAP strategies is reported as ubiquitous, and acknowledged to confer a sense of reassurance to the surgeon despite potential non-concordance with guidelines or clinical efficacy. CONCLUSIONS: Surgical-specific concerns have thus far not been meaningfully integrated into antimicrobial stewardship (AMS) programmes, including important dynamics of confidence, trust and mitigating fear of adverse infective events. Surgeons require specific forms of AMS support to enact optimisation, including support for strong collaborative ownership of the surgical risk of infection, and intra-specialty (within surgical specialties) and inter-specialty (between surgery, anaesthetics and infectious diseases) intervention strategies to establish endorsement of and address barriers to guideline implementation.


Assuntos
Antibacterianos , Antibioticoprofilaxia , Gestão de Antimicrobianos , Fidelidade a Diretrizes , Pesquisas sobre Atenção à Saúde , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Antibacterianos/uso terapêutico , Resistência Microbiana a Medicamentos , Medicina Baseada em Evidências , Feminino , Humanos , Prescrição Inadequada , Masculino , New South Wales/epidemiologia , Cultura Organizacional , Padrões de Prática Médica , Pesquisa Qualitativa
18.
AIDS Res Ther ; 15(1): 6, 2018 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-29519243

RESUMO

OBJECTIVE: To assess the prevalence of non-AIDS co-morbidities (NACs) and predictors of adverse health outcomes amongst people living with HIV in order to identify health needs and potential gaps in patient management. DESIGN: Retrospective, non-consecutive medical record audit of patients attending a publicly funded HIV clinic in metropolitan Sydney analysed for predictors of adverse health outcomes. We developed a scoring system based on the validated Charlson score method for NACs, mental health and social issues and confounders were selected using directed acyclic graph theory under the principles of causal inference. RESULTS: 211 patient files were audited non-consecutively over 6 weeks. 89.5% were male; 41.8% culturally and linguistically diverse and 4.1% were of Aboriginal/Torres Strait Islander origin. Half of patients had no general practitioner and 25% were ineligible for Medicare subsidised care. The most common NACs were: cardiovascular disease (25%), hepatic disease (21%), and endocrinopathies (20%). One-third of patients had clinical anxiety, one-third major depression and almost half of patients had a lifetime history of tobacco smoking. Five predictors of poor health outcomes were identified: (1) co-morbidity score was associated with hospitalisation (odds ratio, OR 1.58; 95% CI 1.01-2.46; p = 0.044); (2) mental health score was associated with hospitalisation (OR 1.79; 95% CI 1.22-2.62; p = 0.003) and poor adherence to ART (OR 2.34; 95% CI 1.52-3.59; p = 0.001); (3) social issues score was associated with genotypic resistance (OR 2.61; 95% CI 1.48-4.59; p = 0.001), co-morbidity score (OR 1.69; 95% CI 1.24-2.3; p = 0.001) and hospitalisation (OR 1.72; 95% CI 1.1-2.7; p = 0.018); (4) body mass index < 20 was associated with genotypic resistance (OR 6.25; 95% CI 1.49-26.24; p = 0.012); and (5) Medicare eligibility was associated with co-morbidity score (OR 2.21; 95% CI 1.24-3.95; p = 0.007). CONCLUSION: Most HIV patients are healthy due to effective antiretroviral therapy; however, NACs and social/mental health issues are adding to patient complexity. The current findings underpin the need for multidisciplinary management beyond routine viral load and CD4 count monitoring.


Assuntos
Infecções por HIV/epidemiologia , Síndrome da Imunodeficiência Adquirida/epidemiologia , Terapia Antirretroviral de Alta Atividade , Contagem de Linfócito CD4 , Comorbidade , HIV/genética , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Saúde Mental , Avaliação de Resultados em Cuidados de Saúde , Prognóstico , Fatores de Risco , Carga Viral
20.
Intern Med J ; 48(12): 1514-1520, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30517986

RESUMO

There is a global outbreak of infections due to Mycobacterium chimaera associated with cardiac surgery. The most serious infections involve prosthetic material implantation, and all have followed surgical procedures involving cardiopulmonary bypass. We describe a cluster of four cases following cardiac surgery at a tertiary referral centre in Sydney, Australia. We report novel clinical findings, including haemolysis and kidney rupture possibly related to immune reconstitution inflammatory syndrome. The positive effect of corticosteroids on haemodynamic function in two cases and the failure of currently recommended antimicrobial therapy to sterilise prosthetic valve material in the absence of surgery despite months of treatment are also critically examined. Positron emission tomography was positive in two cases despite normal transoesophageal echocardiograms. The proportion of cases with M. chimaera infection after aortic valve replacement (4/890, 0.45%; 95% confidence interval 0.18-1.15%) was significantly higher than after all other cardiothoracic surgical procedures (0/2433, 0%; 95% confidence interval 0-0.16%).


Assuntos
Antibacterianos , Valva Aórtica , Implante de Prótese de Valva Cardíaca/efeitos adversos , Próteses Valvulares Cardíacas/microbiologia , Infecções por Mycobacterium não Tuberculosas , Mycobacterium , Complicações Pós-Operatórias , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/administração & dosagem , Antibacterianos/classificação , Valva Aórtica/microbiologia , Valva Aórtica/cirurgia , Austrália/epidemiologia , Feminino , Doenças das Valvas Cardíacas/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium/efeitos dos fármacos , Mycobacterium/isolamento & purificação , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Infecções por Mycobacterium não Tuberculosas/etiologia , Tomografia por Emissão de Pósitrons/métodos , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/microbiologia , Medição de Risco , Fatores de Risco , Resultado do Tratamento
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