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1.
J Gastroenterol Hepatol ; 39(3): 568-575, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38114452

RESUMO

BACKGROUND: Direct-acting antiviral (DAA) therapies for hepatitis C virus infection (HCV) lead to excellent rates of sustained virological response (SVR). However, loss to follow-up (LTFU) for SVR testing remains a challenge. We examine factors associated with LTFU in a real-world setting. METHODS: Adults who received DAA therapy for HCV in one of 26 centers across Australia during 2016-2021 were followed up for 2 years. Data sources included the patient medical records and the national Pharmaceutical and Medicare Benefits Schemes. Linkage to Medicare provided utilization data of other health-care providers and re-treatment with DAAs. LTFU was defined as no clinic attendance for SVR testing by at least 52 weeks after DAA treatment commencement. Multivariable logistic regression assessed factors associated with LTFU. RESULTS: In 3619 patients included in the study (mean age 52.0 years; SD = 10.5), 33.6% had cirrhosis (69.4% Child-Pugh class B/C), and 19.3% had HCV treatment prior to the DAA era. Five hundred and fifteen patients (14.2%) were LTFU. HCV treatment initiation in 2017 or later (adj-OR = 2.82, 95% confidence interval [CI] 2.25-3.54), younger age (adj-OR = 2.63, 95% CI 1.80-3.84), Indigenous identification (adj-OR = 1.99, 95% CI 1.23-3.21), current injection drug use or opioid replacement therapy (adj-OR = 1.66, 95% CI 1.25-2.20), depression treatment (adj-OR = 1.49, 95% CI 1.17-1.90), and male gender (adj-OR = 1.31, 95% CI 1.04-1.66) were associated with LTFU. CONCLUSIONS: These findings stress the importance of strengthening the network of providers caring for patients with HCV. In particular, services targeting vulnerable groups of patients such as First Nations Peoples, youth health, and those with addiction and mental health disorders should be equipped to treat HCV.


Assuntos
Hepatite C Crônica , Hepatite C , Adulto , Humanos , Masculino , Idoso , Adolescente , Pessoa de Meia-Idade , Antivirais/uso terapêutico , Programas Nacionais de Saúde , Hepatite C/tratamento farmacológico , Hepacivirus , Resposta Viral Sustentada , Assistência ao Paciente , Continuidade da Assistência ao Paciente
2.
BMC Psychiatry ; 24(1): 103, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321403

RESUMO

BACKGROUND: Severe deterioration in mental health and disrupted care provision during the COVID-19 increased unmet needs for mental health. This review aimed to identify changes in mental health services for patients in response to the pandemic and understand the impact of the changes on patients and providers. METHODS: Following the Cochrane guidance for rapid reviews, Cochrane CENTRAL, MEDLINE, Embase and PsycInfo were searched for empirical studies that investigated models of care, services, initiatives or programmes developed/evolved for patients receiving mental health care during COVID-19, published in English and undertaken in high-income countries. Thematic analysis was conducted to describe the changes and an effect direction plot was used to show impact on outcomes. RESULTS: 33 of 6969 records identified were included reporting on patients' experiences (n = 24), care providers' experiences (n = 7) and mixed of both (n = 2). Changes reported included technology-based care delivery, accessibility, flexibility, remote diagnostics and evaluation, privacy, safety and operating hours of service provision. These changes had impacts on: (1) care access; (2) satisfaction with telehealth; (3) comparability of telehealth with face-to-face care; (4) treatment effectiveness; (5) continuity of care; (6) relationships between patients and care providers; (7) remote detection and diagnostics in patients; (8) privacy; (9) treatment length and (10) work-life balance. CONCLUSIONS: A shift to telecommunication technologies had a significant impact on patients and care providers' experiences of mental health care. Improvements to care access, flexibility, remote forms of care delivery and lengths of operating service hours emerged as crucial changes, which supported accessibility to mental health services, increased attendance and reduced dropouts from care. The relationships between patients and care providers were influenced by service changes and were vastly depending on technological literacy and context of patients and availability and care access ranging from regular contact to a loss of in-person contact. The review also identified an increase in care inequality and a feeling of being disconnected among marginalised groups including homeless people, veterans and ethic minority groups. Telehealth in mental care could be a viable alternative to face-to-face service delivery with effective treatment outcomes. Further research is needed to better understand the impact of the changes identified particularly on underserved populations.


Assuntos
COVID-19 , Serviços de Saúde Mental , Humanos , Pandemias , Países Desenvolvidos , Atenção à Saúde
3.
J Hepatol ; 77(5): 1287-1298, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35870702

RESUMO

BACKGROUND & AIMS: RNA interference therapy has been shown to reduce hepatitis B surface antigen (HBsAg) levels in preclinical models, which could confer functional cure in patients with chronic hepatitis B. This phase IIa trial (ClinicalTrials.gov Identifier: NCT03365947) assessed the safety and efficacy of the small-interfering RNA JNJ-73763989 (JNJ-3989) plus a nucleos(t)ide analogue (NA), with/without the capsid assembly modulator JNJ-56136379 (JNJ-6379) in patients with chronic hepatitis B. METHODS: Treatment-naïve and NA-suppressed patients received 3 subcutaneous JNJ-3989 doses every week (QW; 100, 200, or 300 mg), 2 weeks (Q2W; 100 mg) or 4 weeks (Q4W; 25, 50, 100, 200, 300, or 400 mg), or JNJ-3989 Q4W (200 mg) plus oral JNJ-6379 250 mg daily for 12 weeks. Patients received NAs throughout. RESULTS: Eighty-four patients were recruited. All treatments were well tolerated, with all 5 serious adverse events considered unrelated to study drugs. JNJ-3989 100 to 400 mg Q4W resulted in HBsAg reductions ≥1 log10 IU/ml from baseline in 39/40 (97.5%) patients at the nadir. All patients receiving the triple combination (n = 12) had HBsAg reductions ≥1 log10 IU/ml from baseline at the nadir. HBsAg reductions were similar for HBeAg-positive (n = 21) and HBeAg-negative (n = 47) patients in all JNJ-3989 Q4W treatment arms, including the triple combination (n = 68). Smaller HBsAg reductions were seen with 25 mg (n = 8) and 50 mg (n = 8) than with 100 to 400 mg (n = 40). Shorter dosing intervals (QW [n = 12] and Q2W [n = 4]) did not improve response vs. Q4W dosing. HBsAg reductions ≥1 log10 IU/ml from baseline persisted in 38% of patients 336 days after the last JNJ-3989 dose. CONCLUSIONS: JNJ-3989 plus an NA, with/without JNJ-6379, was well tolerated and resulted in HBsAg reductions up to 336 days after the last JNJ-3989 Q4W dose. CLINICAL TRIAL NUMBER: NCT03365947. LAY SUMMARY: Hepatitis B virus affects people's livers and produces particles called hepatitis B surface antigen (HBsAg) that damage a person's liver and can help the virus infect a person for a long time, known as chronic hepatitis B (CHB). In this study, a new treatment called JNJ-3989 was assessed (in combination with normal treatment known as nucleos(t)ide analogues), for its safety and effectiveness in reducing the number of HBsAg particles in people with CHB. The results of this study showed that treatment with JNJ-3989 could be safe for people with CHB, lowered their HBsAg levels, and kept HBsAg levels lowered for 336 days in 38% of patients after receiving their last dose of JNJ-3989.


Assuntos
Hepatite B Crônica , RNA Interferente Pequeno , Humanos , Antivirais/uso terapêutico , Antígenos E da Hepatite B , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Compostos Orgânicos , RNA Interferente Pequeno/uso terapêutico , Resultado do Tratamento , Quimioterapia Combinada/efeitos adversos
4.
Liver Transpl ; 28(2): 236-246, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34624175

RESUMO

Introduction of universal access to direct-acting antiviral (DAA) therapy for hepatitis C virus (HCV) in Australia and New Zealand on March 1st , 2016, has had a major impact on the number of people with chronic HCV infection, but the impact on liver transplantation rates is unknown. We conducted a retrospective registry study including all adult liver transplantations from the Australia and New Zealand Liver and Intestinal Liver Transplant Registry (ANZLITR) data set. Interrupted time series analysis determined the impact of DAAs in 2016 on the number of HCV liver transplantations per year. Cox regression analysis was used to determine the impact of DAAs on post-liver transplantation survival. Between January 1, 1990, and December 31, 2019 5318 adult liver transplantations were performed, and 29% (1531) were for HCV infection. Prior to the introduction of DAAs, there was a mean increase of 3.5 adult liver transplantations performed for HCV per annum, but between 2016 and 2019 there was a mean decrease of 7.9 adult liver transplantations per annum (P < 0.001). Similarly, the proportion of liver transplantations performed for HCV increased from 9% (1990) to 33% in 2016 and then fell to 23% in 2019 (P < 0.001). The number and proportion of patients with HCV added to the liver transplantation waiting list also fell in 2016 (P < 0.001) when compared with other indications. The introduction of DAAs was associated with a 31% reduction in death after liver transplantation, adjusted for age at transplant and hepatocellular carcinoma (HCC; hazard ratio [HR], 0.69; 95% confidence interval [CI], 0.48-0.99; P = 0.047). The number of adult liver transplantations performed for HCV-related liver cirrhosis and HCC has reduced since the introduction of universal access to DAAs in 2016 in Australia and New Zealand.


Assuntos
Carcinoma Hepatocelular , Hepatite C Crônica , Hepatite C , Neoplasias Hepáticas , Transplante de Fígado , Adulto , Antivirais/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/cirurgia , Hepacivirus , Hepatite C/complicações , Hepatite C/tratamento farmacológico , Hepatite C/epidemiologia , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/epidemiologia , Humanos , Transplante de Fígado/efeitos adversos , Nova Zelândia/epidemiologia , Estudos Retrospectivos
5.
J Med Virol ; 94(12): 6116-6121, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35982504

RESUMO

HBV RNA is used as a marker of cccDNA transcription and is applicable in the setting of nucleos(t)ide analog (NA) treatment, which suppresses HBV DNA. Traditional assays for quantification of HBV RNA rely on labor-intensive 3'RACE assays targeting the polyA tail. In this study, the high-throughput Roche cobas®HBV RNA investigational assay was assessed on the Roche cobas® 6800 automated platform. Of 969 samples collected for a NA treatment cessation trial, and tested on the cobas assay, 249 were analyzed for sensitivity, reproducibility, sample type applicability, and results were compared to a RACE-based assay. Results of 97 paired serum and plasma samples demonstrated an excellent correlation of 0.98. However, 14.5% of plasma samples yielded detectable (below the limit of quantification) results, when the paired serum was undetectable, and plasma was shown to yield a statistically significant (p < 0.001) greater mean 0.119 log10 copies/ml. Quantification of 152 samples showed good correlation (0.91) between the cobas and RACE assays. The cobas assay demonstrated superior lower limit of quantification, 10 copies/ml, which resulted in detection of 13.2% more samples than the RACE assay. Reproducibility and linear range of the automated assay were also confirmed. The Roche cobas assay for HBV RNA is sensitive and highly recommended.


Assuntos
DNA Viral , Vírus da Hepatite B , DNA Viral/genética , Vírus da Hepatite B/genética , Humanos , Nucleosídeos/uso terapêutico , RNA , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Carga Viral/métodos
6.
BMC Gastroenterol ; 22(1): 16, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35012471

RESUMO

BACKGROUND: A widely used method in assessing small bowel permeability is the lactulose:mannitol test, where the lactulose:mannitol ratio (LMR) is measured. However, there is discrepancy in how the test is conducted and in the values of LMR obtained across studies. This meta-analysis aims to determine LMR in healthy subjects, coeliac and Crohn's disease. METHODS: A literature search was performed using PRISMA guidance to identify studies assessing LMR in coeliac or Crohn's disease. 19 studies included in the meta-analysis measured gut permeability in coeliac disease, 17 studies in Crohn's disease. Outcomes of interest were LMR values and comparisons of standard mean difference (SMD) and weighted mean difference (WMD) in healthy controls, inactive Crohn's, active Crohn's, treated coeliac and untreated coeliac. Pooled estimates of differences in LMR were calculated using the random effects model. RESULTS: Pooled LMR in healthy controls was 0.014 (95% CI: 0.006-0.022) while pooled LMRs in untreated and treated coeliac were 0.133 (95% CI: 0.089-0.178) and 0.037 (95% CI: 0.019-0.055). In active and inactive Crohn's disease, pooled LMRs were 0.093 (95% CI: 0.031-0.156) and 0.028 (95% CI: 0.015-0.041). Significant differences were observed in LMR between: (1) healthy controls and treated coeliacs (SMD = 0.409 95% CI 0.034 to 0.783, p = 0.032), (2) healthy controls and untreated coeliacs (SMD = 1.362 95% CI: 0.740 to 1.984, p < 0.001), (3) treated coeliacs and untreated coeliacs (SMD = 0.722 95% CI: 0.286 to 1.157, p = 0.001), (4) healthy controls and inactive Crohn's (SMD = 1.265 95% CI: 0.845 to 1.686, p < 0.001), (5) healthy controls and active Crohn's (SMD = 2.868 95% CI: 2.112 to 3.623, p < 0.001), and (6) active Crohn's and inactive Crohn's (SMD = 1.429 (95% CI: 0.580 to 2.278, p = 0.001). High heterogeneity was observed, which was attributed to variability in protocols used across different studies. CONCLUSION: The use of gut permeability measurements in screening and monitoring of coeliac and Crohn's disease is promising. LMR is useful in performing this function with significant limitations. More robust alternative tests with higher degrees of clinical evidence are needed if measurements of gut permeability are to find widespread clinical use.


Assuntos
Doença Celíaca , Doença de Crohn , Humanos , Lactulose , Manitol , Permeabilidade
7.
BMC Public Health ; 22(1): 536, 2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35303855

RESUMO

BACKGROUND: Hepatitis B is a chronic viral infection, a leading cause of primary liver cancer and identified as a major public health priority by the World Health Organization. Despite a high proportion of people in Australia who have been diagnosed with hepatitis B, significant gaps remain in health care access and in accurate knowledge about hepatitis B. Most people with hepatitis B in Australia were born in China, where the infection has an intergenerational impact with significant social implications resulting from the infection. Understanding how people of Chinese ethnicity with hepatitis B understand and respond to hepatitis B is imperative for reducing morbidity, mortality, and the personal and social impact of the infection. METHODS: Qualitative semi-structured interviews with people with hepatitis B of Chinese ethnicity recruited through a specialist service identified the advice people with hepatitis B thought was important enough to inform the experience of people newly diagnosed with hepatitis B. A thematic analysis of the data privileged the lived experience of participants and their personal, rather than clinical, explanations of the virus. RESULTS: Hepatitis B infection had psychological and physical consequences that were informed by cultural norms, and to which people had responded to with significant behavioural change. Despite this cohort being engaged with specialist clinical services with access to the most recent, comprehensive, and expert information, much of the advice people with hepatitis B identified as important for living with hepatitis B was not based on biomedical understandings. Key suggestions from people with hepatitis B were to form sustainable clinical relationships, develop emotional resilience, make dietary changes, regulate energy, and issues related to disclosure. CONCLUSIONS: The study highlights conflicts between biomedical and public health explanations and the lived experience of hepatitis B among people of Chinese ethnicity in Australia. Beliefs about hepatitis B are embedded within cultural understandings of health that can conflict with bio-medical explanations of the infection. Acknowledging these perspectives provides for insightful communication between health services and their clients, and the development of nuanced models of care informed by the experience of people with hepatitis B.


Assuntos
Hepatite B , Povo Asiático , Austrália , China/epidemiologia , Etnicidade , Hepatite B/diagnóstico , Humanos
8.
Gut ; 2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103403

RESUMO

Gut function remains largely underinvestigated in undernutrition, despite its critical role in essential nutrient digestion, absorption and assimilation. In areas of high enteropathogen burden, alterations in gut barrier function and subsequent inflammatory effects are observable but remain poorly characterised. Environmental enteropathy (EE)-a condition that affects both gut morphology and function and is characterised by blunted villi, inflammation and increased permeability-is thought to play a role in impaired linear growth (stunting) and severe acute malnutrition. However, the lack of tools to quantitatively characterise gut functional capacity has hampered both our understanding of gut pathogenesis in undernutrition and evaluation of gut-targeted therapies to accelerate nutritional recovery. Here we survey the technology landscape for potential solutions to improve assessment of gut function, focussing on devices that could be deployed at point-of-care in low-income and middle-income countries (LMICs). We assess the potential for technological innovation to assess gut morphology, function, barrier integrity and immune response in undernutrition, and highlight the approaches that are currently most suitable for deployment and development. This article focuses on EE and undernutrition in LMICs, but many of these technologies may also become useful in monitoring of other gut pathologies.

9.
J Viral Hepat ; 28(6): 925-933, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33662159

RESUMO

An estimated 18% of people living with chronic hepatitis B (CHB) in Australia were born in China. While guideline-based care, including regular clinical monitoring and timely treatment, prevent CHB-related cirrhosis, cancer and deaths, over three-quarters of people with CHB do not receive guideline-based care in Australia. This qualitative study aimed to identify enablers to engagement in CHB clinical management among ethnic Chinese people attending specialist care. Participants self-identified as of Chinese ethnicity and who attended specialist care for CHB clinical management were interviewed in Melbourne in 2019 (n = 30). Semi-structured interviews covered experiences of diagnosis and engagement in clinical management services, and advice for people living with CHB. Interviews were recorded with consent; data were transcribed verbatim and thematically analysed. Receiving clear information about the availability of treatment and/or the necessity of long-term clinical management were the main enablers for participants to engage in CHB clinical management. Additional enablers identified to maintain regular clinical monitoring included understanding CHB increases risks of cirrhosis and liver cancer, using viral load indicators to visualize disease status in patient-doctor communication; expectations from family, peer group and medical professionals; use of a patient recall system; availability of interpreters or multilingual doctors; and largely subsidized healthcare services. In conclusion, to support people attending clinical management for CHB, a holistic response from community, healthcare providers and the public health sector is required. There are needs for public health programmes directed to communicate (i) CHB-related complications; (ii) availability of effective and cheap treatment; and that (iii) long-term engagement with clinical management and its benefits.


Assuntos
Hepatite B Crônica , Hepatite B , Austrália/epidemiologia , China/epidemiologia , Etnicidade , Hepatite B Crônica/tratamento farmacológico , Humanos
10.
Proc Natl Acad Sci U S A ; 115(8): E1779-E1788, 2018 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-29432173

RESUMO

Numerous posttranslational modifications have been described in kinesins, but their consequences on motor mechanics are largely unknown. We investigated one of these-acetylation of lysine 146 in Eg5-by creating an acetylation mimetic lysine to glutamine substitution (K146Q). Lysine 146 is located in the α2 helix of the motor domain, where it makes an ionic bond with aspartate 91 on the neighboring α1 helix. Molecular dynamics simulations predict that disrupting this bond enhances catalytic site-neck linker coupling. We tested this using structural kinetics and single-molecule mechanics and found that the K146Q mutation increases motor performance under load and coupling of the neck linker to catalytic site. These changes convert Eg5 from a motor that dissociates from the microtubule at low load into one that is more tightly coupled and dissociation resistant-features shared by kinesin 1. These features combined with the increased propensity to stall predict that the K146Q Eg5 acetylation mimetic should act in the cell as a "brake" that slows spindle pole separation, and we have confirmed this by expressing this modified motor in mitotically active cells. Thus, our results illustrate how a posttranslational modification of a kinesin can be used to fine tune motor behavior to meet specific physiological needs.


Assuntos
Cinesinas/química , Cinesinas/metabolismo , Mitose/fisiologia , Sequência de Aminoácidos , Fenômenos Biomecânicos , Células HeLa , Humanos , Modelos Moleculares , Mutação , Conformação Proteica
11.
Pediatr Cardiol ; 42(6): 1341-1349, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33891133

RESUMO

Myocardial strain offers new insights into ventricular performance, There are software packages from several different companies used to ascertain this, and little data is available in patients with single right ventricle (sRV) physiology. We aimed to compare the analysis of two strain software applications using a cohort of patients with sRV for both inter-vendor and inter-observer variability. Echocardiograms from 85 patients with sRV (122 separate studies) were prospectively evaluated. All had Glenn and/or Fontan palliation. Longitudinal 4-chamber (4LS), inflow/outflow (IO), circumferential, and radial strain were assessed using Velocity Vector Imaging (VVI, Seimens, Munich) and Automated Functional Imaging (AFI, General Electric, Boston) software. In a subset of 45 patients (61 separate studies), strain measurements were obtained by two sonographers so a paired "inter-observer" analysis could be performed. A moderate correlation between measurements made by the two systems was observed. Circumferential strain assessment had the highest R value (0.77) with all others having R values < 0.6. Both software packages showed modest inter-observer reproducibility for longitudinal and circumferential strain. VVI intraclass correlation coefficients (ICC) for 4LS and average circumferential strain (ACS) were 0.6 and 0.58, compared to 0.68 and 0.59 for AFI. Other than radial strain and VVI IO inferior strain, mean strain differences between AFI and VVI were ≤ 1%. Inter-observer variability is modest, however, mean differences are minimal suggesting reasonable clinical reliability. Inter-vendor variability is greater and not as clinically reliable. In patients with sRV, serial assessments with strain should be performed using the same software.


Assuntos
Ecocardiografia/métodos , Ventrículos do Coração/diagnóstico por imagem , Contração Miocárdica/fisiologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Técnica de Fontan/métodos , Ventrículos do Coração/fisiopatologia , Ventrículos do Coração/cirurgia , Humanos , Lactente , Masculino , Curva ROC , Reprodutibilidade dos Testes , Adulto Jovem
12.
Transfus Med Hemother ; 48(2): 118-129, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33976612

RESUMO

BACKGROUND AND OBJECTIVES: Pre-donation screening of potential blood donors is critical for ensuring the safety of the donor blood supply, and donor deferral as a result of risk factors is practised worldwide. This systematic review was conducted in the context of an expert review convened by the Australian Red Cross Lifeblood in 2013 to consider Lifeblood's injecting drug use (IDU)-related policies and aimed to identify studies assessing interventions to improve compliance with deferral criteria in blood donation settings. MATERIALS AND METHODS: MEDLINE/PubMed, OVID Medline, OVID Embase, LILACS, and the Cochrane Library (CENTRAL and DARE) databases were searched for studies conducted within blood donation settings that examined interventions to increase blood donor compliance with deferral criteria. Observational and experimental studies from all geographical areas were considered. RESULTS: Ten studies were identified that tested at least one intervention to improve blood donor compliance with deferral criteria, including computerized interviews or questionnaires, direct and indirect oral questioning, educational materials, and a combination of a tickbox questionnaire and a personal donor interview. High-quality evidence from a single study was provided for the effectiveness of a computerized interview in improving detection of HIV risk behaviour. Low-quality evidence for the effectiveness of computerized interviews was provided by 3 additional studies. Two studies reported a moderate effect of direct questioning in increasing donor deferral, but the quality of the evidence was low. CONCLUSION: This review identified several interventions to improve donor compliance that have been tested in blood donation settings and provided evidence for the effectiveness of computerized interviews in improving detection of risk factors.

13.
Molecules ; 26(3)2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33504099

RESUMO

Antibiotic resistance is a growing concern that is driving the exploration of alternative ways of killing bacteria. Here we show that gold nanoparticles synthesized by the mycelium of Mucor plumbeus are an effective medium for antimicrobial photodynamic therapy (PDT). These particles are spherical in shape, uniformly distributed without any significant agglomeration, and show a single plasmon band at 522-523 nm. The nanoparticle sizes range from 13 to 25 nm, and possess an average size of 17 ± 4 nm. In PDT, light (from a source consisting of nine LEDs with a peak wavelength of 640 nm and FWMH 20 nm arranged in a 3 × 3 array), a photosensitiser (methylene blue), and oxygen are used to kill undesired cells. We show that the biogenic nanoparticles enhance the effectiveness of the photosensitiser, methylene blue, and so can be used to kill both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. The enhanced effectiveness means that we could kill these bacteria with a simple, small LED-based light source. We show that the biogenic gold nanoparticles prevent fast photobleaching, thereby enhancing the photoactivity of the methylene blue (MB) molecules and their bactericidal effect.


Assuntos
Anti-Infecciosos/química , Ouro/química , Nanopartículas Metálicas/química , Azul de Metileno/química , Fotodegradação/efeitos dos fármacos , Fotoquimioterapia/métodos , Anti-Infecciosos/farmacologia , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Mucor/química , Micélio/química , Oxigênio/química , Tamanho da Partícula , Fármacos Fotossensibilizantes/química , Staphylococcus aureus/efeitos dos fármacos
14.
J Hepatol ; 72(3): 431-440, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31655134

RESUMO

BACKGROUND & AIMS: Direct-acting antiviral (DAA) therapy for HCV has high efficacy and limited toxicity. We hypothesised that the efficacy of glecaprevir-pibrentasvir for chronic HCV with a simplified treatment monitoring schedule would be non-inferior to a standard treatment monitoring schedule. METHODS: In this open-label multicentre phase IIIb trial, treatment-naïve adults with chronic HCV without cirrhosis were randomly assigned (2:1) to receive glecaprevir-pibrentasvir 300 mg-120 mg daily for 8 weeks administered with a simplified or standard monitoring strategy. Clinic visits occurred at baseline and post-treatment week 12 in the simplified arm, and at baseline, week 4, week 8, and post-treatment week 12 in the standard arm. Study nurse phone contact occurred at week 4 and week 8 in both arms. Participants requiring adherence support were not eligible, including those reporting recent injecting drug use. The primary endpoint was sustained virological response at post-treatment week 12 (SVR12), with a non-inferiority margin of 6%. RESULTS: Overall, 380 participants (60% male, 47% genotype 1, 32% genotype 3) with chronic HCV were randomised and treated with glecaprevir-pibrentasvir in the simplified (n = 253) and standard (n = 127) arms. In the intention-to-treat population, SVR12 was 92% (95% CI 89%-95%) in the simplified and 95% (95% CI 92%-99%) in the standard arm (difference between arms -3.2%; 95% CI -8.2% to 1.8%) and did not reach non-inferiority. In the per-protocol population, SVR12 was 97% (95% CI 96%-99%) in the simplified and 98% (95% CI 96%-100%) in the standard arm. No treatment-related serious adverse events were reported. CONCLUSIONS: In patients with chronic HCV infection without cirrhosis, treatment with glecaprevir-pibrentasvir was safe and effective. In comparison to standard monitoring, a simplified monitoring schedule did not achieve non-inferiority. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT03117569. LAY SUMMARY: Direct-acting antiviral (DAA) therapy for hepatitis C is highly effective and well tolerated. The SMART-C randomised trial evaluated an 8-week regimen of glecaprevir-pibrentasvir for hepatitis C treatment, using a simplified monitoring schedule that included no pathology tests or clinic visits during treatment. This simplified strategy produced a high cure rate (92%), but this was not equivalent to the standard monitoring schedule cure rate (95%).


Assuntos
Ácidos Aminoisobutíricos/administração & dosagem , Antivirais/administração & dosagem , Benzimidazóis/administração & dosagem , Ciclopropanos/administração & dosagem , Monitoramento de Medicamentos/métodos , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Lactamas Macrocíclicas/administração & dosagem , Leucina/análogos & derivados , Prolina/análogos & derivados , Pirrolidinas/administração & dosagem , Quinoxalinas/administração & dosagem , Sulfonamidas/administração & dosagem , Adulto , Idoso , Ácidos Aminoisobutíricos/efeitos adversos , Antivirais/efeitos adversos , Benzimidazóis/efeitos adversos , Ciclopropanos/efeitos adversos , Combinação de Medicamentos , Feminino , Genótipo , Hepatite C Crônica/virologia , Humanos , Lactamas Macrocíclicas/efeitos adversos , Leucina/administração & dosagem , Leucina/efeitos adversos , Masculino , Adesão à Medicação , Pessoa de Meia-Idade , Prolina/administração & dosagem , Prolina/efeitos adversos , Pirrolidinas/efeitos adversos , Quinoxalinas/efeitos adversos , Sulfonamidas/efeitos adversos , Resposta Viral Sustentada , Adulto Jovem
15.
Microbiology (Reading) ; 166(1): 34-43, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31585061

RESUMO

Microbial biofilms are ubiquitous in drinking water systems, yet our understanding of drinking water biofilms lags behind our understanding of those in other environments. Here, a six-member model bacterial community was used to identify the interactions and individual contributions of each species to community biofilm formation. These bacteria were isolated from the International Space Station potable water system and include Cupriavidus metallidurans, Chryseobacterium gleum, Ralstonia insidiosa, Ralstonia pickettii, Methylorubrum (Methylobacterium) populi and Sphingomonas paucimobilis, but all six species are common members of terrestrial potable water systems. Using reconstituted assemblages, from pairs to all 6 members, community biofilm formation was observed to be robust to the absence of any single species and only removal of the C. gleum/S. paucimobilis pair, out of all 15 possible 2-species subtractions, led to loss of community biofilm formation. In conjunction with these findings, dual-species biofilm formation assays supported the view that the contribution of C. gleum to community biofilm formation was dependent on synergistic biofilm formation with either R. insidiosa or C. metallidurans. These data support a model of multiple, partially redundant species interactions to generate robustness in biofilm formation. A bacteriophage and multiple predatory bacteria were used to test the resilience of the community to the removal of individual members in situ, but the combination of precise and substantial depletion of a single target species was not achievable. We propose that this assemblage can be used as a tractable model to understand the molecular bases of the interactions described here and to decipher other functions of drinking water biofilms.


Assuntos
Biofilmes/crescimento & desenvolvimento , Água Potável/microbiologia , Interações Microbianas/fisiologia , Microbiota , Bactérias/classificação , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Bactérias/virologia , Bacteriófagos/fisiologia , Astronave , Microbiologia da Água
16.
J Gastroenterol Hepatol ; 34(1): 40-48, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30151932

RESUMO

Viral hepatitis affects more than 320 million people globally, leading to significant morbidity and mortality due to liver failure and hepatocellular carcinoma (HCC). More than 248 million people (3.2% globally) are chronically infected with hepatitis B virus (HBV), and an estimated 80 million people (1.1% globally) are chronically infected with hepatitis C virus (HCV). In 2015, more than 700 000 deaths were directly attributable to HBV, and nearly 500 000 deaths were attributable to HCV infection; 2-5% of HBV-infected people develop HCC per annum irrespective of the presence of cirrhosis, whereas 1-5% HCV-infected people with advanced fibrosis develop HCC per annum. The rapidly escalating global mortality related to HBV and HCV related viral hepatitis to be the 7th leading cause of death worldwide in 2013, from 10th leading cause in 1990. Australia, New Zealand, and Pacific Island Countries and Territories fall within the World Health Organization Western Pacific Region, which has a high prevalence of viral hepatitis and related morbidity, particularly HBV. Remarkably, in this region, HBV-related mortality is greater than for tuberculosis, HIV infection, and malaria combined. The region provides a unique contrast in viral hepatitis prevalence, health system resources, and approaches taken to achieve World Health Organization global elimination targets for HBV and HCV infection. This review highlights the latest evidence in viral hepatitis epidemiology and explores the health resources available to combat viral hepatitis, focusing on the major challenges and critical needs to achieve elimination in Australia, New Zealand, and Pacific Island Countries and Territories.


Assuntos
Carcinoma Hepatocelular/epidemiologia , Hepatite Viral Humana/epidemiologia , Hepatite Viral Humana/prevenção & controle , Cirrose Hepática/epidemiologia , Neoplasias Hepáticas/epidemiologia , Australásia/epidemiologia , Carcinoma Hepatocelular/virologia , Objetivos , Hepatite Viral Humana/diagnóstico , Hepatite Viral Humana/tratamento farmacológico , Humanos , Cirrose Hepática/virologia , Neoplasias Hepáticas/virologia , Programas de Rastreamento , Organização Mundial da Saúde
17.
N Engl J Med ; 373(27): 2608-17, 2015 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-26575258

RESUMO

BACKGROUND: In phase 2 trials, treatment with the combination of the nucleotide polymerase inhibitor sofosbuvir and the NS5A inhibitor velpatasvir resulted in high rates of sustained virologic response in patients chronically infected with hepatitis C virus (HCV) genotype 2 or 3. METHODS: We conducted two randomized, phase 3, open-label studies involving patients who had received previous treatment for HCV genotype 2 or 3 and those who had not received such treatment, including patients with compensated cirrhosis. In one trial, patients with HCV genotype 2 were randomly assigned in a 1:1 ratio to receive sofosbuvir-velpatasvir, in a once-daily, fixed-dose combination tablet (134 patients), or sofosbuvir plus weight-based ribavirin (132 patients) for 12 weeks. In a second trial, patients with HCV genotype 3 were randomly assigned in a 1:1 ratio to receive sofosbuvir-velpatasvir for 12 weeks (277 patients) or sofosbuvir-ribavirin for 24 weeks (275 patients). The primary end point for the two trials was a sustained virologic response at 12 weeks after the end of therapy. RESULTS: Among patients with HCV genotype 2, the rate of sustained virologic response in the sofosbuvir-velpatasvir group was 99% (95% confidence interval [CI], 96 to 100), which was superior to the rate of 94% (95% CI, 88 to 97) in the sofosbuvir-ribavirin group (P=0.02). Among patients with HCV genotype 3, the rate of sustained virologic response in the sofosbuvir-velpatasvir group was 95% (95% CI, 92 to 98), which was superior to the rate of 80% (95% CI, 75 to 85) in the sofosbuvir-ribavirin group (P<0.001). The most common adverse events in the two studies were fatigue, headache, nausea, and insomnia. CONCLUSIONS: Among patients with HCV genotype 2 or 3 with or without previous treatment, including those with compensated cirrhosis, 12 weeks of treatment with sofosbuvir-velpatasvir resulted in rates of sustained virologic response that were superior to those with standard treatment with sofosbuvir-ribavirin. (Funded by Gilead Sciences; ASTRAL-2 ClinicalTrials.gov number, NCT02220998; and ASTRAL-3, NCT02201953.).


Assuntos
Antivirais/uso terapêutico , Carbamatos/uso terapêutico , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Compostos Heterocíclicos de 4 ou mais Anéis/uso terapêutico , Sofosbuvir/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antivirais/efeitos adversos , Carbamatos/efeitos adversos , Combinação de Medicamentos , Farmacorresistência Viral , Feminino , Genótipo , Hepatite C Crônica/complicações , Hepatite C Crônica/virologia , Compostos Heterocíclicos de 4 ou mais Anéis/efeitos adversos , Humanos , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Sofosbuvir/efeitos adversos , Resultado do Tratamento , Proteínas não Estruturais Virais/antagonistas & inibidores , Adulto Jovem
18.
Small ; 14(16): e1703964, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29479810

RESUMO

Microscale robotic devices have myriad potential applications including drug delivery, biosensing, cell manipulation, and microsurgery. In this work, a tethered, 3D, compliant grasper with an integrated force sensor is presented, the entirety of which is fabricated on the tip of an optical fiber in a single-step process using 2-photon polymerization. This gripper can prove useful for the interrogation of biological microstructures such as alveoli, villi, or even individual cells. The position of the passively actuated grasper is controlled via micromanipulation of the optical fiber, and the microrobotic device measures approximately 100 µm in length and breadth. The force estimation is achieved using optical interferometry: high-dimensional spectral readings are used to train artificial neural networks to predict the axial force exerted on/by the gripper. The design, characterization, and testing of the grasper are described and its real-time force-sensing capability with an accuracy below 2.7% of the maximum calibrated force is demonstrated.

19.
Hepatology ; 66(4): 1083-1089, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28498551

RESUMO

The optimal retreatment strategy for patients chronically infected with hepatitis C virus who experience virologic failure after treatment with direct-acting antiviral-based therapies remains unclear. In this multicenter, open-label, phase 2 study, we evaluated the efficacy and safety of a fixed-dose combination of sofosbuvir-velpatasvir (400 mg/100 mg) plus weight-adjusted ribavirin administered for 24 weeks in patients who did not achieve sustained virologic response after prior treatment with direct-acting antiviral regimens that included the nucleotide analogue nonstructural protein 5B inhibitor sofosbuvir plus the nonstructural protein 5A inhibitor velpatasvir with or without the nonstructural protein 3/4A protease inhibitor voxilaprevir. The primary efficacy endpoint was the proportion of patients achieving sustained virologic response at 12 weeks after the cessation of treatment. In total, 63 of 69 (91%; 95% confidence interval, 82%-97%) patients achieved sustained virologic response at 12 weeks, including 36 of 37 (97%; 95% confidence interval, 86%-100%) patients with hepatitis C virus genotype 1 infection, 13 of 14 (93%; 95% confidence interval, 66%-100%) patients with genotype 2 infection, and 14 of 18 (78%; 95% confidence interval, 52%-94%) patients with genotype 3 infection. Most adverse events were of mild or moderate severity. The most frequently reported adverse events were fatigue, nausea, headache, insomnia, and rash. One patient (1%) with genotype 1a infection discontinued all study drugs due to an adverse event (irritability). CONCLUSION: Retreatment of patients who previously failed direct-acting antiviral-based therapies with sofosbuvir-velpatasvir plus ribavirin for 24 weeks was well tolerated and effective, particularly those with hepatitis C virus genotype 1 or 2 infection. (Hepatology 2017;66:1083-1089).


Assuntos
Antivirais/uso terapêutico , Carbamatos/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Compostos Heterocíclicos de 4 ou mais Anéis/uso terapêutico , Ribavirina/uso terapêutico , Sofosbuvir/uso terapêutico , Adulto , Idoso , Combinação de Medicamentos , Farmacorresistência Viral/genética , Quimioterapia Combinada , Feminino , Hepacivirus/genética , Humanos , Masculino , Pessoa de Meia-Idade
20.
Opt Express ; 26(11): 14186-14200, 2018 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-29877460

RESUMO

Fiber-optic sensors have numerous existing and emerging applications spanning areas from industrial process monitoring to medical diagnosis. Two of the most common fiber sensors are based on the fabrication of Bragg gratings or Fabry-Perot etalons. While these techniques offer a large array of sensing targets, their utility can be limited by the difficulties involved in fabricating forward viewing probes (Bragg gratings) and in obtaining sufficient signal-to-noise ratios (Fabry-Perot systems). In this article we present a micro-scale fiber-optic force sensor produced using direct laser writing (DLW). The fabrication entails a single-step process that can be undertaken in a reliable and repeatable manner using a commercial DLW system. The sensor is made of a series of thin plates (i.e. Fabry-Perot etalons), which are supported by springs that compress under an applied force. At the proximal end of the fiber, the interferometric changes that are induced as the sensor is compressed are read out using reflectance spectroscopy, and the resulting spectral changes are calibrated with respect to applied force. This calibration is performed using either singular value decomposition (SVD) followed by linear regression or artificial neural networks. We describe the design and optimization of this device, with a particular focus on the data analysis required for calibration. Finally, we demonstrate proof-of-concept force sensing over the range 0-50 µN, with a measurement error of approximately 1.5 µN.


Assuntos
Tecnologia de Fibra Óptica/instrumentação , Interferometria/instrumentação , Lasers , Aprendizado de Máquina , Calibragem , Desenho de Equipamento , Análise de Falha de Equipamento , Redes Neurais de Computação , Fenômenos Físicos , Refratometria/instrumentação , Redação
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