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1.
J Hosp Infect ; 147: 146-157, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522561

RESUMO

Bacteria commonly adhere to surfaces and produce polymeric material to encase the attached cells to form communities called biofilms. Within these biofilms, bacteria can appear to be many times more resistant to antibiotics or disinfectants. This systematic review explores the prevalence and microbial profile associated with biofilm production of bacteria isolated from endotracheal tubes and its associations with antimicrobial resistance. A comprehensive search was performed on databases PubMed, Embase, and Google Scholar for relevant articles published between 1st January 2000 and 31st December 2022. The relevant articles were exported to Mendeley Desktop 1.19.8 and screened by title and abstract, followed by full text screening based on the eligibility criteria of the study. Quality assessment of the studies was performed using the Newcastle-Ottawa Scale (NOS) customized for cross-sectional studies. Furthermore, the prevalence of antimicrobial resistance in biofilm-producers isolated from endotracheal tube specimens was investigated. Twenty studies encompassing 981 endotracheal tubes met the eligibility criteria. Pseudomonas spp. and Acinetobacter spp. were predominant isolates among the biofilm producers. These biofilms provided strong resistance against commonly used antibiotics. The highest resistance rate observed in Pseudomonas spp. was against fluoroquinolones whereas the least resistance was seen against piperacillin-tazobactam. A similar trend of susceptibility was observed in Acinetobacter spp. with a very high resistance rate against fluoroquinolones, third-generation cephalosporins and carbapenems. In conclusion, endotracheal tubes were associated with colonization by biofilm forming bacteria with varying levels of antimicrobial resistance. Biofilms may promote the occurrence of recalcitrant infections in endotracheal tubes which need to be managed with appropriate protocols and antimicrobial stewardship. Research focus should shift towards meticulous exploration of biofilm-associated infections to improve detection and management.


Assuntos
Biofilmes , Farmacorresistência Bacteriana , Intubação Intratraqueal , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Humanos , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Bactérias/classificação
2.
Mol Ther ; 32(4): 1061-1079, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38382529

RESUMO

Complement-mediated diseases can be treated using systemic inhibitors. However, complement components are abundant in circulation, affecting systemic inhibitors' exposure and efficacy. Furthermore, because of complement's essential role in immunity, systemic treatments raise infection risk in patients. To address these challenges, we developed antibody fusion proteins combining the alternative-pathway complement inhibitor factor H (fH1-5) with an anti-C3d monoclonal antibody (C3d-mAb-2fH). Because C3d is deposited at sites of complement activity, this molecule localizes to tissue complement while minimizing circulating complement engagement. These fusion proteins bind to deposited complement in diseased human skin sections and localize to activated complement in a primate skin injury model. We further explored the pharmacology of C3d-mAb-2fH proteins in rodent models with robust tissue complement activation. Doses of C3d-mAb-2fH >1 mg/kg achieved >75% tissue complement inhibition in mouse and rat injury models while avoiding circulating complement blockade. Glomerular-specific complement inhibition reduced proteinuria and preserved podocyte foot-process architecture in rat membranous nephropathy, indicating disease-modifying efficacy. These data indicate that targeting local tissue complement results in durable and efficacious complement blockade in skin and kidney while avoiding systemic inhibition, suggesting broad applicability of this approach in treating a range of complement-mediated diseases.


Assuntos
Fator H do Complemento , Nefropatias , Humanos , Camundongos , Ratos , Animais , Fator H do Complemento/genética , Complemento C3d/metabolismo , Nefropatias/etiologia , Anticorpos , Ativação do Complemento
4.
Cancer Epidemiol Biomarkers Prev ; 32(1): 91-97, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36620897

RESUMO

BACKGROUND: Through adequate screening and follow-up, cervical cancer can be prevented or detected at early-stage (stage I), which is related to excellent survival. Current guidelines recommend discontinuing screening for women ≥65 years with history of normal Pap and/or HPV tests, potentially leaving this age group vulnerable. This study examined late-stage disease in a population-based cohort. METHODS: Using California Cancer Registry data, we identified 12,442 patients ages ≥21 years with a first primary cervical cancer diagnosed during 2009-2018. Proportions of late-stage disease (stages II-IV) and early- and late-stage 5-year relative survival are presented by the age group. Among patients ages ≥65 years, multivariable logistic regression estimated associations of sociodemographic and clinical characteristics with late-stage cervical cancer. RESULTS: Nearly one fifth of patients (n = 2,171, 17.4%) were ≥65 years. More women ages ≥65 years (71%) presented with late-stage disease than younger women (48% in patients ages <65). Late-stage 5-year relative survival was lower for women ≥65 years (23.2%-36.8%) compared with patients <65 (41.5%-51.5%). Characteristics associated with late-stage cervical cancer in women ≥65 years included older age [odds ratio (OR), 1.02; 95% confidence interval (CI), 1.01-1.04; each year], non-adenocarcinoma histologic subtypes, and comorbidities (OR, 1.59; 95% CI, 1.21-2.08). CONCLUSIONS: There remains a significant burden of advanced cervical cancer in women ≥65. IMPACT: Efforts should be made to better understand how the current screening paradigm is failing women of 65 years and older. Future work should focus on determining past screening history, lapses in follow-up care, and non-invasive testing approaches.


Assuntos
Infecções por Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , Adulto Jovem , Adulto , Idoso , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/patologia , Esfregaço Vaginal , Teste de Papanicolaou , Programas de Rastreamento , Sistema de Registros , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/complicações , California/epidemiologia , Detecção Precoce de Câncer
5.
Hong Kong Med J ; 28(6): 430-437, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36442841

RESUMO

INTRODUCTION: The global neonatal death (NND) rate has been declining in recent decades, but there are no comprehensive data concerning the characteristics of NNDs in Hong Kong. This study investigated the trends and aetiologies of NNDs among singleton pregnancies in Hong Kong. METHODS: This study included all cases of NND from singleton pregnancies in a tertiary hospital in Hong Kong between 2000 and 2019. The rates, clinical characteristics, and aetiologies of NND were compared between the first (2000-2009) and the second (2010-2019) decades. RESULTS: The NND rate decreased from 1.66/1000 livebirths (97 cases) in the first decade to 1.32/1000 livebirths (87 cases) in the second decade. Congenital or genetic abnormalities (82 cases) caused 44.6% of all NNDs. There was a significant reduction from 0.82/1000 livebirths in the first decade to 0.52/1000 livebirths in the second decade (P=0.037). Other causes of NND were prematurity (69 cases; 37.5%), sepsis (16 cases; 8.7%), hypoxic-ischaemic encephalopathy (15 cases; 8.2%), and sudden infant death syndrome (2 cases; 1.1%). Gestational age-specific neonatal mortality for moderately preterm neonates (31-33 weeks of gestation) significantly decreased from 34.73/1000 in 2000-2009 to 8.63/1000 in 2010-2019 (P=0.001), but there were no significant changes in neonatal mortality for other gestations. CONCLUSION: The NND rate in Hong Kong is among the lowest worldwide. Neonatal deaths in our centre declined over the past two decades, mainly because of improvements in the prenatal diagnosis and treatment of congenital or genetic abnormalities, as well as an improved survival rate among moderately preterm neonates.


Assuntos
Mortalidade Infantil , Recém-Nascido Prematuro , Gravidez , Recém-Nascido , Lactente , Feminino , Humanos , Estudos Retrospectivos , Hong Kong/epidemiologia
6.
Water Sci Technol ; 85(4): 1065-1078, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35228354

RESUMO

The molybdenum (Mo) non-point source pollution in the mining area has an irreversible impact on the surrounding water and soil ecosystems. Herein, three integrated vertical subsurface flow constructed wetlands (CWs) were constructed to assess the effects of combination substrates and plant on the removal of Mo(VI). Results showed that CW1 with combination substrates and cattail exhibited a favorable removal performance for Mo(VI) at 80.90%. Moreover, most Mo(VI) retained in the CWs was retained in the substrate (58.13-88.04%), and the largest fraction of Mo(VI) retained was the water-soluble fraction on the surface of the combination substrates. Mo(VI) removal was also influenced by the microbial community composition in substrate, especially their co-occurrence networks. The species that showed significant positive correlation with Mo(VI) removal were Planctomycetes, Latescibacteria, Armatimonadetes, and Gemmatimonadetes. Moreover, CWs added plants showed that more co-occurrences interaction between taxa occurs, which means that the wetlands efficiently select recruitment of potential microbial consortia and change the co-occurrences to remove pollution in the substrate. These results could be useful in providing an ecology-based solution for the treatment of Mo(VI) in wastewater, especially in adjusting the microbial communities for Mo(VI) removal at the genetic level.


Assuntos
Microbiota , Poluentes Químicos da Água , Molibdênio , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Poluentes Químicos da Água/análise , Áreas Alagadas
8.
Ultrasound Obstet Gynecol ; 58(4): 603-608, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33219729

RESUMO

OBJECTIVE: To assess objectively the degree of fetal head elevation achieved by different maneuvers commonly used for managing umbilical cord prolapse. METHODS: This was a prospective observational study of pregnant women at term before elective Cesarean delivery. A baseline assessment of fetal head station was performed with the woman in the supine position, using transperineal ultrasound for measuring the parasagittal angle of progression (psAOP), head-symphysis distance (HSD) and head-perineum distance (HPD). The ultrasonographic measurements of fetal head station were repeated during different maneuvers, including elevation of the maternal buttocks using a wedge, knee-chest position, Trendelenburg position with a 15° tilt and filling the maternal urinary bladder with 100 mL, 300 mL and 500 mL of normal saline. The measurements obtained during the maneuvers were compared with the baseline measurements. RESULTS: Twenty pregnant women scheduled for elective Cesarean section at term were included in the study. When compared with baseline (median psAOP, 103.6°), the knee-chest position gave the strongest elevation effect, with the greatest reduction in psAOP (psAOP, 80.7°; P < 0.001), followed by filling the bladder with 500 mL (psAOP, 89.9°; P < 0.001) and 300 mL (psAOP, 94.4°; P < 0.001) of normal saline. Filling the maternal bladder with 100 mL of normal saline (psAOP, 96.1°; P = 0.001), the Trendelenburg position (psAOP, 96.8°; P = 0.014) and elevating the maternal buttocks (psAOP, 98.3°; P = 0.033) gave modest elevation effects. Similar findings were reported for HSD and HPD. The fetal head elevation effects of the knee-chest position, Trendelenburg position and elevation of the maternal buttocks were independent of the initial fetal head station, but that of bladder filling was greater when the initial head station was low. CONCLUSIONS: To elevate the fetal presenting part, the knee-chest position provides the best effect, followed by filling the maternal urinary bladder with 500 mL then 300 mL of fluid, respectively. Filling the bladder with 100 mL of fluid, the Trendelenburg position and elevation of the maternal buttocks have modest effects. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Feto/diagnóstico por imagem , Cabeça/embriologia , Apresentação no Trabalho de Parto , Posicionamento do Paciente/métodos , Ultrassonografia Pré-Natal/métodos , Adulto , Cesárea , Feminino , Feto/embriologia , Humanos , Períneo/diagnóstico por imagem , Gravidez , Período Pré-Operatório , Prolapso , Estudos Prospectivos , Nascimento a Termo/fisiologia , Cordão Umbilical
9.
Ultrasound Obstet Gynecol ; 57(3): 459-465, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32198896

RESUMO

OBJECTIVE: To evaluate the utility of expanded non-invasive prenatal screening (NIPS), compared with chromosomal microarray analysis (CMA), for the detection of chromosomal abnormalities in high-risk pregnancies. METHODS: This was a multicenter retrospective study of singleton pregnancies at high risk for chromosomal abnormality. Patients who underwent expanded NIPS and CMA sequentially during pregnancy from 2015 to 2019 were included in the analysis. Pregnancies with a positive result for sex chromosome aneuploidy were excluded as the full details could not be retrieved. The utility of expanded NIPS and CMA for detection of chromosomal abnormalities in this cohort was compared by assessing the concordance between the results. RESULTS: Of the 774 included high-risk pregnancies, 550 (71.1%) had a positive NIPS result, while a positive CMA result was detected in 308 (39.8%) cases. The rate of full or partial concordance between NIPS and CMA was 82.2%, 59.6% and 25.0% for trisomies 21, 18 and 13, respectively. For rare aneuploidies and segmental imbalances, NIPS and CMA results were fully or partially concordant in 7.5% and 33.3% of cases, respectively. Copy-number variants < 5 Mb were detected more often by CMA, with an incidence of 7.9% (61/774) compared with 3.1% (24/774) by NIPS. A genetic aberration was detected by CMA in 1 in 17 (5.8%) high-risk pregnancies that had a negative or non-reportable NIPS result. CONCLUSION: CMA allows for comprehensive detection of genome-wide chromosomal abnormalities in high-risk pregnancies. CMA should be offered instead of expanded NIPS for high-risk pregnancies. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Aberrações Cromossômicas/embriologia , Transtornos Cromossômicos/diagnóstico , Análise em Microsséries/estatística & dados numéricos , Teste Pré-Natal não Invasivo/estatística & dados numéricos , Gravidez de Alto Risco/genética , Adulto , Transtornos Cromossômicos/embriologia , Feminino , Humanos , Análise em Microsséries/métodos , Teste Pré-Natal não Invasivo/métodos , Gravidez , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto Jovem
11.
Ultrasound Obstet Gynecol ; 58(2): 214-220, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-32730679

RESUMO

OBJECTIVE: To investigate whether gestational age at intervention (< or ≥ 16 weeks) and other factors affect the risk of loss of the cotwin after selective fetal reduction using radiofrequency ablation (RFA) in monochorionic (MC) pregnancy. METHODS: This was a single-center retrospective analysis of 63 consecutive RFA procedures performed at our institution from January 2011 to October 2019 for selective fetal reduction in complicated MC pregnancies. Indications for RFA were twin reversed arterial perfusion sequence (13 cases), twin-to-twin transfusion syndrome (12 cases), twin anemia-polycythemia sequence (two cases), selective fetal growth restriction (10 cases), discordant anomalies (17 cases) and multifetal pregnancy reduction in triplets or quadruplets with a MC pair (nine cases). Twenty-six (41.3%) of these procedures were performed before and 37 (58.7%) after 16 weeks. Potential factors that could affect the risk of loss of the cotwin, including gestational age at RFA, order of multiple pregnancy, amnionicity, indication for RFA and number of ablation cycles, were assessed first by univariate analysis and then by multivariate analysis. RESULTS: There were 17 (27.0%) cotwin losses. Ablation cycles numbering four or more was the only factor among those investigated to be associated with loss of the cotwin after RFA (P = 0.035; odds ratio, 5.21), while the indication for RFA, order of multiple pregnancy, amnionicity and gestational age at RFA had no effect. Comparing RFA performed at < 16 vs ≥ 16 weeks, there was no difference in the rate of cotwin loss (23.1% vs 29.7%; P = 0.558) or preterm prelabor rupture of the membranes before 34 weeks (7.7% vs 5.4%; P = 0.853), or in the median gestational age at delivery (36.2 vs 37.3 weeks; P = 0.706). CONCLUSIONS: RFA is a promising tool for early selective fetal reduction in MC pregnancy before 16 weeks. Four or more ablation cycles is a major risk factor for cotwin loss. Careful assessment pre- and post-RFA, together with proficient operative skills to minimize the number of ablation cycles, are the mainstay to ensure that this procedure is effective and safe. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Redução de Gravidez Multifetal , Gravidez Múltipla , Adulto , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Complicações Pós-Operatórias , Gravidez , Resultado da Gravidez , Trimestres da Gravidez , Ablação por Radiofrequência , Estudos Retrospectivos
12.
J Asthma ; 57(8): 820-828, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31082287

RESUMO

Introduction: Asthma evidence-based interventions (EBI) are implemented in the home, school, community or primary care setting. Although families are engaged in one setting, they often have to navigate challenges in another setting.Objective: Our objective is to design and implement a comprehensive plan which integrates EBI's and connects the four sectors in underserved communities such as Philadelphia.Methods: September 2015-April 2016 we implemented a three-pronged strategy to understand needs and resources of the community including 1) focus groups and key informant interviews, 2) secondary data analysis and 3) pilot testing for implementation to determine gaps in care, and opportunities to overcome those gaps.Results: Analysis of the focus group and key informant responses showed themes: diagnosis fear, clinician time, home and school asthma trigger exposures, school personnel training and communication gaps across all four sectors. EBI's were evaluated and selected to address identified themes. Pilot testing of a community health worker (CHW) intervention to connect home, primary care and school resulted in an efficient transfer of asthma medications and medication administration forms to the school nurse office for students with uncontrolled asthma addressing a common delay leading to poor asthma management in school.Conclusion: Thus far there has been limited success in reducing asthma disparities for low-income minority children. This study offers hope that strategically positioning CHWs may work synergistically to close gaps in care and result in improved asthma control and reduced asthma disparities.


Assuntos
Asma/prevenção & controle , Serviços de Saúde Comunitária/organização & administração , Implementação de Plano de Saúde/economia , Disparidades nos Níveis de Saúde , Serviços de Saúde Escolar/organização & administração , Adolescente , Asma/diagnóstico , Asma/economia , Criança , Pré-Escolar , Serviços de Saúde Comunitária/economia , Medicina Baseada em Evidências/economia , Medicina Baseada em Evidências/organização & administração , Feminino , Grupos Focais , Acessibilidade aos Serviços de Saúde/economia , Acessibilidade aos Serviços de Saúde/organização & administração , Humanos , Renda , Lactente , Recém-Nascido , Masculino , Saúde das Minorias/economia , Philadelphia , Projetos Piloto , Pesquisa Qualitativa , Serviços de Saúde Escolar/economia
13.
Hong Kong Med J ; 24(3): 226-237, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29888706

RESUMO

INTRODUCTION: Newborn screening is important for early diagnosis and effective treatment of inborn errors of metabolism (IEM). In response to a 2008 coroners' report of a 14-year-old boy who died of an undiagnosed IEM, the OPathPaed service model was proposed. In the present study, we investigated the feasibility of the OPathPaed model for delivering expanded newborn screening in Hong Kong. In addition, health care professionals were surveyed on their knowledge and opinions of newborn screening for IEM. METHODS: The present prospective study involving three regional hospitals was conducted in phases, from 1 October 2012 to 31 August 2014. The 10 steps of the OPathPaed model were evaluated: parental education, consent, sampling, sample dispatch, dried blood spot preparation and testing, reporting, recall and counselling, confirmation test, treatment and monitoring, and cost-benefit analysis. A fully automated online extraction system for dried blood spot analysis was also evaluated. A questionnaire was distributed to 430 health care professionals by convenience sampling. RESULTS: In total, 2440 neonates were recruited for newborn screening; no true-positive cases were found. Completed questionnaires were received from 210 respondents. Health care professionals supported implementation of an expanded newborn screening for IEM. In addition, there is a substantial need of more education for health care professionals. The majority of respondents supported implementing the expanded newborn screening for IEM immediately or within 3 years. CONCLUSION: The feasibility of OPathPaed model has been confirmed. It is significant and timely that when this pilot study was completed, a government-led initiative to study the feasibility of newborn screening for IEM in the public health care system on a larger scale was announced in the Hong Kong Special Administrative Region Chief Executive Policy Address of 2015.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde , Erros Inatos do Metabolismo/diagnóstico , Triagem Neonatal/métodos , Diagnóstico Precoce , Feminino , Hong Kong , Humanos , Recém-Nascido , Masculino , Erros Inatos do Metabolismo/terapia , Projetos Piloto , Guias de Prática Clínica como Assunto , Estudos Prospectivos , Inquéritos e Questionários
14.
J Laryngol Otol ; 131(7): 585-592, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28502275

RESUMO

BACKGROUND: Acellular dermal matrices are increasingly used in laryngotracheal and pharyngeal reconstruction, but specific indications and the type of acellular dermal matrix used vary. The authors systematically reviewed outcomes relating to acellular dermal matrix use in head and neck reconstruction. METHODS: Electronic databases were searched through 1 May 2016 for literature on acellular dermal matrix use in laryngotracheal and pharyngeal reconstruction. Studies were appraised for surgical indications, outcomes and study design. RESULTS: Eleven publications with 170 cases were included. Eight articles reported on acellular dermal matrix use in oncological reconstruction. Most studies were case series; no high-level evidence studies were identified. Graft extrusion was more common in non-oncological applications. In general, post-oncological reconstruction with an acellular dermal matrix demonstrated complication rates similar to those reported without an acellular dermal matrix. CONCLUSION: Evidence in support of acellular dermal matrix use in head and neck reconstruction is generally poor. Prospective comparative studies are required to define the indications, safety and effectiveness of acellular dermal matrices in laryngotracheal and pharyngeal reconstruction.


Assuntos
Derme Acelular , Carcinoma de Células Escamosas/cirurgia , Cervicoplastia/métodos , Neoplasias Otorrinolaringológicas/cirurgia , Carcinoma de Células Escamosas/patologia , Seguimentos , Neoplasias Laríngeas/cirurgia , Estadiamento de Neoplasias , Neoplasias Otorrinolaringológicas/patologia , Neoplasias Faríngeas/cirurgia , Retalhos Cirúrgicos/cirurgia , Neoplasias da Traqueia/cirurgia , Resultado do Tratamento
17.
Aliment Pharmacol Ther ; 44(9): 957-966, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27629859

RESUMO

BACKGROUND: In patients with chronic hepatitis B, tenofovir disoproxil fumarate (TDF) plus pegylated interferon (PEG-IFN) for 48-weeks results in higher rates of hepatitis B surface antigen (HBsAg) loss than either monotherapy. AIM: To identify baseline and on-treatment factors associated with HBsAg loss at Week 72 and provide a model for predicting HBsAg loss in patients receiving combination therapy for 48 weeks. METHODS: A secondary analysis of data from an open-label study where patients were randomised to TDF (300 mg/day, oral) plus PEG-IFN (PI, 180 µg/week, subcutaneous) for 48 weeks (TDF/PI-48w); TDF plus PEG-IFN for 16 weeks, TDF for 32 weeks (TDF/PI-16w+TDF-32w); TDF for 120 weeks (TDF-120w) or PEG-IFN for 48 weeks (PI-48w). Logistic regression methods were used to identify models that best predicted HBsAg loss at Week 72. RESULTS: Rates of HBsAg loss at Week 72 were significantly higher in the TDF/PI-48w group (6.5%) than in the TDF/PI-16w+TDF-32w (0.5%), TDF-120w (0%) and PI-48w (2.2%) groups (P = 0.09). The only baseline factor associated with response was genotype A. HBsAg decline at Week 12 or 24 of treatment was associated with HBsAg loss at Week 72 (P < 0.001). HBsAg decline >3.5 log10 IU/mL at Week 24 in the TDF/PI-48w group resulted in a positive predictive value of 85% and a negative predictive value of 99% for HBsAg loss at Week 72. CONCLUSIONS: HBsAg decline at Week 24 of TDF plus PEG-IFN combination therapy may identify patients who, after completing 48 weeks of treatment, have a better chance of achieving HBsAg loss at Week 72.


Assuntos
Antivirais/administração & dosagem , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/administração & dosagem , Polietilenoglicóis/administração & dosagem , Tenofovir/administração & dosagem , Administração Oral , Adulto , DNA Viral/sangue , Quimioterapia Combinada , Feminino , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Humanos , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Proteínas Recombinantes/administração & dosagem , Resultado do Tratamento
18.
Nat Nanotechnol ; 11(9): 741-6, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27294504

RESUMO

A major achievement of the past decade has been the realization of macroscopic quantum systems by exploiting the interactions between optical cavities and mechanical resonators. In these systems, phonons are coherently annihilated or created in exchange for photons. Similar phenomena have recently been observed through phonon-cavity coupling-energy exchange between the modes of a single system mediated by intrinsic material nonlinearity. This has so far been demonstrated primarily for bulk crystalline, high-quality-factor (Q > 10(5)) mechanical systems operated at cryogenic temperatures. Here, we propose graphene as an ideal candidate for the study of such nonlinear mechanics. The large elastic modulus of this material and capability for spatial symmetry breaking via electrostatic forces is expected to generate a wealth of nonlinear phenomena, including tunable intermodal coupling. We have fabricated circular graphene membranes and report strong phonon-cavity effects at room temperature, despite the modest Q factor (∼100) of this system. We observe both amplification into parametric instability (mechanical lasing) and the cooling of Brownian motion in the fundamental mode through excitation of cavity sidebands. Furthermore, we characterize the quenching of these parametric effects at large vibrational amplitudes, offering a window on the all-mechanical analogue of cavity optomechanics, where the observation of such effects has proven elusive.

19.
Cytoskeleton (Hoboken) ; 73(8): 377-95, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27232264

RESUMO

Several glomerular pathologies resulting from podocyte injury are linked to genetic variation involving the MYH9 gene, which encodes the heavy chain of non-muscle myosin-IIA (NM-IIA). However, the functional role of NM-IIA has not been studied extensively in podocytes. We hypothesized that NM-IIA is critical for maintenance of podocyte structure and mechanical function. To test this hypothesis, we studied murine podocytes in vitro subjected to blebbistatin inhibition of NM-II activity, or RNA interference-mediated, isoform-specific ablation of Myh9 gene and protein (NM-IIA) or its paralog Myh10 gene and protein (NM-IIB). Using quantitative immunofluorescence microscopy, traction force microscopy, and attachment and "wound healing" assays, we found that NM-IIA ablation altered podocyte actin cytoskeletal structure and focal adhesion distribution, decreased cell attachment and contractility, and increased cell motility. Blebbistatin treatment had similar effects. NM-IIB ablation produced cells that exhibited poor attachment, but cytoskeletal structural organization, contractility and motility were maintained. These findings indicate that NM-IIA is essential for maintenance of podocyte cytoskeletal structure and mechanical function in vitro, and NM-IIB does not replace it in this role when NM-IIA expression is altered. We conclude that critical podocyte functions may be affected by MYH9 mutations or disease-associated haplotypes. © 2016 Wiley Periodicals, Inc.


Assuntos
Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Miosina não Muscular Tipo IIA/metabolismo , Podócitos/metabolismo , Movimento Celular , Humanos , Contração Muscular , Podócitos/patologia
20.
Proc Natl Acad Sci U S A ; 112(30): 9484-9, 2015 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-26170290

RESUMO

In a classic model of mammalian brain formation, precursors of principal glutamatergic neurons migrate radially along radial glia fibers whereas GABAergic interneuron precursors migrate tangentially. These migration modes have significant implications for brain function. Here we used clonal lineage tracing of active radial glia-like neural stem cells in the adult mouse dentate gyrus and made the surprising discovery that proliferating neuronal precursors of glutamatergic granule neurons exhibit significant tangential migration along blood vessels, followed by limited radial migration. Genetic birthdating and morphological and molecular analyses pinpointed the neuroblast stage as the main developmental window when tangential migration occurs. We also developed a partial "whole-mount" dentate gyrus preparation and observed a dense plexus of capillaries, with which only neuroblasts, among the entire population of progenitors, are directly associated. Together, these results provide insight into neuronal migration in the adult mammalian nervous system.


Assuntos
Encéfalo/metabolismo , Giro Denteado/fisiologia , Glutamina/química , Neurogênese/fisiologia , Neurônios/fisiologia , Animais , Mapeamento Encefálico/métodos , Movimento Celular , Feminino , Proteínas de Fluorescência Verde/metabolismo , Hipocampo/fisiologia , Imageamento Tridimensional , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia Confocal , Microscopia de Fluorescência , Modelos Neurológicos , Células-Tronco Neurais/citologia , Neurônios/citologia
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