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1.
J Minim Invasive Gynecol ; 29(5): 683-690, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35085838

RESUMEN

STUDY OBJECTIVE: Evaluate inter-rater and intrarater reliability of a novel scoring tool for surgical complexity assessment of endoscopic hysterectomy. DESIGN: Validation study. SETTING: Academic medical center. PARTICIPANTS: Total of 11 academic obstetrician-gynecologists with varying years of postresidency training, clinical practice, and surgical volumes. INTERVENTIONS: Application of a novel scoring tool to evaluate surgical complexity of 150 sets of images taken in a standardized fashion before surgical intervention (global pelvis, anterior cul-de-sac, posterior cul-de-sac, right adnexa, left adnexa). Using only these images, raters were asked to assess uterine size, number, and location of myomas, adnexal and uterine mobility, need for ureterolysis, and presence of endometriosis or adhesions in relevant locations. Surgical complexity was staged on a scale of 1 to 4 (low to high complexity). MEASUREMENTS AND MAIN RESULTS: Number of postresidency years in practice for participating surgeons ranged from 2 to 15, with an average of 8 years. A total of 8 obstetrician-gynecologists (72.7%) had completed a fellowship in minimally invasive gynecologic surgery. Six (54.6%) reported an annual volume of >50 hysterectomies. Raters reported that 95.4% of the images were satisfactory for assessment. Of the 150 sets of images, most were found to be stage 1 to 2 complexity (stage 1: 23.8%, stage 2: 41.6%, stage 3: 32.8%, stage 4: 1.8%). The level of inter-rater agreement regarding stage 1 to 2 vs 3 to 4 complexity was moderate (κ = 0.49; 95% confidence interval [CI], 0.42-0.56). Moderate inter-rater agreement was also found between surgeon raters with an annual hysterectomy volume >50 (κ = 0.49; 95% CI, 0.40-0.57) as well as between surgeon raters with fellowship experience (κ = 0.50; 95% CI, 0.42-0.58). Intrarater agreement averaged 80.2% among all raters and also achieved moderate agreement (mean weighted κ = 0.53; range, 0.38-0.72). CONCLUSION: This novel scoring tool uses clinical assessment of preintervention anatomic images to stratify the surgical complexity of endoscopic hysterectomy. It has rich and comprehensive evaluation capabilities and achieved moderate inter-rater and intrarater agreement. The tool can be used in conjunction with or instead of traditional markers of surgical complexity such as uterine weight, estimated blood loss, and operative time.


Asunto(s)
Fondo de Saco Recto-Uterino , Histerectomía , Femenino , Humanos , Variaciones Dependientes del Observador , Tempo Operativo , Reproducibilidad de los Resultados
2.
Respirology ; 26(2): 147-152, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33319478

RESUMEN

Spirometry has been established as an essential test for diagnosing and monitoring respiratory disease, particularly asthma and COPD, as well as in occupational health surveillance. In Australia and New Zealand, there is currently no pathway for spirometry operators in community-based healthcare settings to demonstrate spirometry competence. The Australia and New Zealand Society of Respiratory Science (ANZSRS) has identified a need for developing a pathway for operators working in community-based practices in Australia and New Zealand to demonstrate spirometry competence and certification. Spirometry certification provides evidence to patients, clients, employers and organizations that an individual has participated in an assessment process that qualifies them to perform spirometry to current international spirometry standards set out by the American Thoracic Society and the European Respiratory Society (ATS/ERS). This document describes a competence assessment pathway that incorporates a portfolio and practical assessment. The completion of this pathway and the award of certification confer an individual is competent to perform spirometry for 3 years, after which re-certification is required. The adoption of this competency assessment and certification process by specialist organizations, and the commitment of operators performing spirometry to undergo this process, will enhance spirometry quality and practice in community-based healthcare settings.


Asunto(s)
Certificación , Servicios de Salud Comunitaria , Sociedades Médicas , Espirometría/normas , Australia , Atención a la Salud , Humanos , Modelos Teóricos , Nueva Zelanda
3.
J Surg Res ; 195(2): 385-9, 2015 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-25777824

RESUMEN

BACKGROUND: Students often experience passive learning in their surgical rotations as they are delegated to holding the camera during laparoscopic cases. We introduced a laparoscopic skills course to medical students to provide hands-on experience. We hypothesized that the course will improve basic laparoscopic skills and increase interest in a surgical career. MATERIALS AND METHODS: All students on the core surgery rotation attended two sessions in the surgical simulation laboratory lead by Department of Surgery faculty members. Surveys were used before and after the course to assess video game (VG) use and interest in a surgical career. Course effectiveness was assessed with a laparoscopic peg transfer exercise. RESULTS: One hundred one students participated with 82 students documenting preinstruction and postinstruction peg transfer times. There was an overall improvement in median transfer times after instruction (before 63 s [interquartile range {IQR} 46-84.5] versus after 50.5 s [IQR 39-65.2], P < 0.001). When stratified by gender, men (n = 40) had faster median preintervention peg transfer times than women (n = 61; 65 s [IQR 51-88]) versus 81 s [IQR 65-98] (P = 0.030). However, both genders had equivalent postinstruction transfer times (men 48 s [IQR 36-61] versus women 51.3 s [IQR 43.2-68.3], P = 0.478). A similar trend was observed between students with and without prior VG use. Of the 50 students who completed both surveys, there was no significant increase (pre-24% versus post-34%, P = 0.29) or decrease (pre-32% versus post-22%, P = 0.13) in interest in a surgical career after the course. CONCLUSIONS: A laparoscopic course for medical students is effective in improving laparoscopic skills. Although male gender and VG use may be associated with better intrinsic skills, instruction and practice allow female students and non-VG users to "catch up." A longer follow-up study is warranted to determine true interest in a surgical career.


Asunto(s)
Competencia Clínica , Laparoscopía/educación , Estudiantes de Medicina , Curriculum , Evaluación Educacional , Femenino , Humanos , Masculino , Estudios Prospectivos , Juegos de Video
4.
Nucleic Acids Res ; 41(4): 2594-608, 2013 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-23275571

RESUMEN

Messenger RNA encoded signals that are involved in programmed -1 ribosomal frameshifting (-1 PRF) are typically two-stemmed hairpin (H)-type pseudoknots (pks). We previously described an unusual three-stemmed pseudoknot from the severe acute respiratory syndrome (SARS) coronavirus (CoV) that stimulated -1 PRF. The conserved existence of a third stem-loop suggested an important hitherto unknown function. Here we present new information describing structure and function of the third stem of the SARS pseudoknot. We uncovered RNA dimerization through a palindromic sequence embedded in the SARS-CoV Stem 3. Further in vitro analysis revealed that SARS-CoV RNA dimers assemble through 'kissing' loop-loop interactions. We also show that loop-loop kissing complex formation becomes more efficient at physiological temperature and in the presence of magnesium. When the palindromic sequence was mutated, in vitro RNA dimerization was abolished, and frameshifting was reduced from 15 to 5.7%. Furthermore, the inability to dimerize caused by the silent codon change in Stem 3 of SARS-CoV changed the viral growth kinetics and affected the levels of genomic and subgenomic RNA in infected cells. These results suggest that the homodimeric RNA complex formed by the SARS pseudoknot occurs in the cellular environment and that loop-loop kissing interactions involving Stem 3 modulate -1 PRF and play a role in subgenomic and full-length RNA synthesis.


Asunto(s)
Sistema de Lectura Ribosómico , ARN Viral/química , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/genética , Secuencia de Bases , Codón , Secuencia Conservada , Dimerización , Secuencias Invertidas Repetidas , Cinética , Magnesio/química , Viabilidad Microbiana , Datos de Secuencia Molecular , Mutación , Resonancia Magnética Nuclear Biomolecular , Conformación de Ácido Nucleico , Temperatura
5.
Clin Infect Dis ; 59(1): 16-23, 2014 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-24704724

RESUMEN

BACKGROUND: Hepatitis B virus (HBV) is an important blood-borne pathogen that causes hepatic inflammation and can lead to liver cirrhosis and hepatocellular carcinoma. Conventional methods of HBV detection are time consuming and require highly trained personnel and elaborate equipment. This report describes the development of a rapid, simple, specific, and sensitive loop-mediated isothermal amplification assay (LAMP) for detection of HBV genotypes A, B, C, D, E, and F in blood samples. METHODS: HBV standard plasma panels and clinical donor plasma specimens were used for the development and validation of the LAMP assay. Amplification was performed at 60°C for 60 minutes using extracted DNA or heat-treated plasma specimens without DNA extraction. The assay was evaluated for its ability to detect various HBV genotypes and for its sensitivity, specificity, and time-point of detection. RESULTS: The LAMP assay detected HBV genotypes A-F and demonstrated a sensitivity of 10-100 IU per reaction of HBV DNA. The assay also detected 69 of 75 (92%) HBV-positive donor plasma specimens tested and demonstrated a specificity of 100%. CONCLUSIONS: These results demonstrate that our HBV-LAMP assay is rapid, sensitive and specific, and capable of detecting the major HBV genotypes. This assay could be used in clinical point-of-care settings, mainly in endemic and resource-limited environments for HBV diagnostics, donor screening, epidemiological studies, and therapeutic monitoring of patients undergoing antiviral treatment.


Asunto(s)
Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B/diagnóstico , Hepatitis B/virología , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , Plasma/virología , Genotipo , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/genética , Humanos , Sistemas de Atención de Punto , Sensibilidad y Especificidad , Temperatura , Factores de Tiempo
6.
Methods Mol Biol ; 2767: 63-74, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37402095

RESUMEN

Understanding the process of human embryo implantation is impeded by the inability to study this phenomenon in vivo, thus limiting opportunities to gain knowledge to in vitro modeling. Previous models have relied on monolayer co-cultures, which do not replicate the complexity of endometrial tissue. Here, we detail the establishment of three-dimensional endometrial assembloids, comprising gland-like epithelial organoids in a stromal matrix. Endometrial assembloids mimic endometrial tissue structure more faithfully and can be used to study human embryo-endometrial interactions. Co-cultures of human embryos and endometrial assembloids will enhance our fundamental understanding of these processes as well as allowing us to study the mechanisms of persistent reproductive failure.


Asunto(s)
Implantación del Embrión , Endometrio , Femenino , Humanos , Blastocisto , Trofoblastos , Técnicas de Cocultivo , Células del Estroma
7.
J Physiother ; 70(2): 124-133, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38494405

RESUMEN

QUESTION: Is remotely delivered physiotherapy as good or better than face-to-face physiotherapy for the management of musculoskeletal conditions? DESIGN: Randomised controlled, non-inferiority trial with concealed allocation, blinded assessors and intention-to-treat analysis. PARTICIPANTS: A total of 210 adult participants with a musculoskeletal condition who presented for outpatient physiotherapy at five public hospitals in Sydney. INTERVENTION: One group received a remotely delivered physiotherapy program for 6 weeks that consisted of one face-to-face physiotherapy session in conjunction with weekly text messages, phone calls at 2 and 4 weeks, and an individualised home exercise program delivered through an app. The other group received usual face-to-face physiotherapy care in an outpatient setting. OUTCOME MEASURES: The primary outcome was the Patient Specific Functional Scale at 6 weeks with a pre-specified non-inferiority margin of -15 out of 100 points. Secondary outcomes included: the Patient Specific Functional Scale at 26 weeks; kinesiophobia, pain, function/disability, global impression of change and quality of life at 6 and 26 weeks; and satisfaction with service delivery at 6 weeks. RESULTS: The mean between-group difference (95% CI) for the Patient Specific Functional Scale at 6 weeks was 2.7 out of 100 points (-3.5 to 8.8), where a positive score favoured remotely delivered physiotherapy. The lower end of the 95% CI was greater than the non-inferiority margin. Whilst non-inferiority margins were not set for the secondary outcomes, the 95% CI of the mean between-group difference ruled out clinically meaningful differences. CONCLUSION: Remotely delivered physiotherapy with support via phone, text and an app is as good as face-to-face physiotherapy for the management of musculoskeletal conditions. TRIAL REGISTRATION: ACTRN12619000065190.


Asunto(s)
Enfermedades Musculoesqueléticas , Calidad de Vida , Adulto , Humanos , Terapia por Ejercicio , Enfermedades Musculoesqueléticas/terapia , Satisfacción del Paciente , Modalidades de Fisioterapia
8.
Physiotherapy ; 124: 143-153, 2024 09.
Artículo en Inglés | MEDLINE | ID: mdl-38901217

RESUMEN

OBJECTIVES: Exercise, support and advice are the key treatment strategies of musculoskeletal problems. The aims of this study were to determine patients', physiotherapists', and other stakeholders' perspectives about supported home physiotherapy for the management of musculoskeletal problems and to identify the barriers and facilitators to rolling out this model of physiotherapy service delivery. METHODS: This study was conducted as part of a process evaluation run alongside a large trial designed to determine whether supported home physiotherapy is as good or better than a course of in-person physiotherapy. Forty interviews were conducted with 20 trial participants, 15 physiotherapists, and 5 other stakeholders. The interviews were semi-structured and based on interview guides. Each interview was transcribed and a three-tiered coding tree was developed. RESULTS: Six key themes were identified. Supported home physiotherapy (i) is convenient for some patients, (ii) does not always align with patients' and therapists' expectations about treatment (iii) is suitable for some but not all, (iv) can reduce personal connection and accountability, (v) has implications for physiotherapists' workloads, and (vi) has barriers and facilitators to future implementation. CONCLUSIONS: Findings suggest that patients are far more accepting of supported home physiotherapy than physiotherapists assume. This model of service delivery could be rolled out to improve access to physiotherapy and to provide a convenient and effective way of delivering physiotherapy to some patients with musculoskeletal conditions if our trial results indicate that supported home physiotherapy is as good or better than in-person physiotherapy. CLINICAL TRIAL REGISTRY NUMBER: ACTRN12619000065190 CONTRIBUTIONS OF THIS PAPER.


Asunto(s)
Servicios de Atención de Salud a Domicilio , Enfermedades Musculoesqueléticas , Fisioterapeutas , Modalidades de Fisioterapia , Investigación Cualitativa , Humanos , Enfermedades Musculoesqueléticas/rehabilitación , Femenino , Masculino , Persona de Mediana Edad , Adulto , Actitud del Personal de Salud , Anciano , Entrevistas como Asunto
9.
BMC Biotechnol ; 13: 72, 2013 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-24047152

RESUMEN

BACKGROUND: Anthrax is a zoonotic disease recognized to affect herbivores since Biblical times and has the widest range of susceptible host species of any known pathogen. The ease with which the bacterium can be weaponized and its recent deliberate use as an agent of terror, have highlighted the importance of gaining a deeper understanding and effective countermeasures for this important pathogen. High quality sequence data has opened the possibility of systematic dissection of how genes distributed on both the bacterial chromosome and associated plasmids have made it such a successful pathogen. However, low transformation efficiency and relatively few genetic tools for chromosomal manipulation have hampered full interrogation of its genome. RESULTS: Group II introns have been developed into an efficient tool for site-specific gene inactivation in several organisms. We have adapted group II intron targeting technology for application in Bacillus anthracis and generated vectors that permit gene inactivation through group II intron insertion. The vectors developed permit screening for the desired insertion through PCR or direct selection of intron insertions using a selection scheme that activates a kanamycin resistance marker upon successful intron insertion. CONCLUSIONS: The design and vector construction described here provides a useful tool for high throughput experimental interrogation of the Bacillus anthracis genome and will benefit efforts to develop improved vaccines and therapeutics.


Asunto(s)
Bacillus anthracis/genética , Marcación de Gen/métodos , Genes Bacterianos , Vectores Genéticos , Cromosomas Bacterianos/genética , Clonación Molecular , ADN Bacteriano/genética , Escherichia coli/genética , Intrones , Mutagénesis Insercional , Conformación de Ácido Nucleico , Plásmidos/genética , Selección Genética
10.
Rheumatology (Oxford) ; 52(8): 1509-19, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23661429

RESUMEN

OBJECTIVE: To determine whether tactile acuity is disrupted in people with knee OA and to determine whether tactile acuity, a clinical signature of primary sensory cortex representation, is related to motor imagery performance (MIP; evaluates working body schema) and pain. METHODS: Experiment 1: two-point discrimination (TPD) threshold at the knee was compared between 20 participants with painful knee OA, 20 participants with arm pain and 20 healthy controls. Experiment 2: TPD threshold, MIP (left/right judgements of body parts) and usual pain were assessed in 20 people with painful knee OA, 17 people with back pain and 38 healthy controls (20 knee TPD; 18 back TPD). RESULTS: People with painful knee OA had larger TPD thresholds than those with arm pain and healthy controls (P < 0.05). TPD and MIP were not related in people with knee OA (P = 0.88) but were related in people with back pain and in healthy controls (P < 0.001). Pain did not relate to TPD threshold or to MIP (P > 0.15 for all). CONCLUSION: In painful knee OA, tactile acuity at the knee is decreased, implying disrupted representation of the knee in primary sensory cortex. That TPD and MIP were unrelated in knee OA, but related in back pain, suggests that the relationship between them may vary between chronic pain conditions. That pain was not related to TPD threshold nor MIP suggests against the idea that disrupted cortical representations contribute to the pain of either condition.


Asunto(s)
Dolor de Espalda/fisiopatología , Osteoartritis de la Rodilla/fisiopatología , Desempeño Psicomotor/fisiología , Tacto/fisiología , Factores de Edad , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Imágenes en Psicoterapia , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Umbral del Dolor , Valores de Referencia , Sensibilidad y Especificidad , Factores Sexuales
11.
ANZ J Surg ; 93(3): 643-648, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36658785

RESUMEN

BACKGROUND: Patients referred to public orthopaedic clinics can experience long waiting times before assessment. This study aims to evaluate the effectiveness of a collaborative Shoulder/Elbow Triage and Assessment (SHELTA) model of care involving orthopaedic surgeons and physiotherapists to reduce the waitlist and improve service and clinical outcomes for patients on an orthopaedic shoulder/elbow clinic waitlist. METHODS: Patients on the waitlist were triaged by surgeons and physiotherapists and invited to an assessment by experienced physiotherapists. Patients were treated nonoperatively or transferred to orthopaedic management based on clinical discussion. The primary outcome was the number of patients on the waitlist. Secondary outcomes included adverse events, patient satisfaction, re-referral and conversion to surgery rates. Pain, function and patient global impression of change were recorded for participants managed nonoperatively. RESULTS: From July 2019 to December 2019, the waitlist reduced from 451 to 298 patients with no adverse events. Seventy-nine patients could not be contacted and 25 no longer required assessment, and were removed from the waitlist. Nonoperatively managed participants reported satisfaction with the service, a median score of 6 on a 7-point Patient Global Impression of Change scale, change in pain of -2.5/10 (95% CI -3.3, -1.7; P < 0.001) on a numerical pain rating scale, and change in function of -17.4/100 (95% CI: -24.1, -10.8; P < 0.001) on the QuickDASH, indicating improvement. CONCLUSIONS: The SHELTA model of care effectively reduced the number of patients on an orthopaedic shoulder/elbow clinic waitlist with good service and clinical outcomes.


Asunto(s)
Ortopedia , Satisfacción del Paciente , Humanos , Hombro , Codo , Triaje , Listas de Espera , Dolor
12.
PLoS Pathog ; 6(5): e1000910, 2010 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-20502631

RESUMEN

HCV (hepatitis C virus) research, including therapeutics and vaccine development, has been hampered by the lack of suitable tissue culture models. Development of cell culture systems for the growth of the most drug-resistant HCV genotype (1b) as well as natural isolates has remained a challenge. Transfection of cultured cells with adenovirus-associated RNA(I) (VA RNA(I)), a known interferon (IFN) antagonist and inhibitor of dsRNA-mediated antiviral pathways, enhanced the growth of plasma-derived HCV genotype 1b. Furthermore, persistent viral growth was achieved after passaging through IFN-alpha/beta-deficient VeroE6 cells for 2 years. Persistently infected cells were maintained in culture for an additional 4 years, and the virus rescued from these cells induced strong cytopathic effect (CPE). Using a CPE-based assay, we measured inhibition of viral production by anti-HCV specific inhibitors, including 2'-C-Methyl-D-Adenosine, demonstrating its utility for the evaluation of HCV antivirals. This virus constitutes a novel tool for the study of one of the most relevant strains of HCV, genotype 1b, which will now be available for HCV life cycle research and useful for the development of new therapeutics.


Asunto(s)
Técnicas de Cultivo de Célula , Hepacivirus/crecimiento & desarrollo , Hepacivirus/genética , Hepatitis C/virología , Transfección/métodos , Adenoviridae/genética , Animales , Antivirales/farmacología , Muerte Celular , Chlorocebus aethiops , Genotipo , Hepacivirus/inmunología , Hepatitis C/sangre , Hepatitis C/tratamiento farmacológico , Anticuerpos contra la Hepatitis C/farmacología , Antígenos de la Hepatitis C/genética , Humanos , Interferón-alfa/genética , Interferón beta/genética , Pruebas de Neutralización , Estabilidad del ARN , ARN Viral/farmacología , Células Vero
13.
Rheumatology (Oxford) ; 51(8): 1455-64, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22467086

RESUMEN

OBJECTIVES: To determine whether motor imagery performance is disrupted in patients with painful knee OA and if this disruption is specific to the location of the pain. METHODS: Twenty patients with painful knee OA, 20 patients with arm pain and 20 healthy pain-free controls undertook a motor imagery task in which they made left/right judgements of pictured hands and feet. Accuracy and reaction time of judgements were compared between groups and pain locations (side: left vs right; site: upper vs lower). RESULTS: Patients with knee pain were less accurate (P < 0.01) than healthy controls, but not different from people with arm pain (all P > 0.11). There were no differences in reaction time between groups (P = 0.64). Further, there was no effect of side or site of pain on reaction time (P = 0.43, 0.54, respectively) and no effect of site of pain on accuracy of left/right judgements (P = 0.12). However, there was an interaction effect of side of pain on accuracy of left vs right images (P = 0.03). If left-sided pain was present, accuracy was lower when images showed left hands/feet than when images showed right hands/feet. CONCLUSION: Motor imagery performance is disrupted in patients with knee OA, but is also disrupted in patients with arm pain. Accuracy of left/right judgements is disrupted in a spatially defined manner, raising the important possibility that brain-grounded maps of peripersonal space contribute to the cortical proprioceptive representation.


Asunto(s)
Artralgia/fisiopatología , Lateralidad Funcional/fisiología , Osteoartritis de la Rodilla/fisiopatología , Desempeño Psicomotor/fisiología , Adulto , Anciano , Brazo , Artralgia/etiología , Estudios de Casos y Controles , Estudios Transversales , Femenino , Humanos , Articulación de la Rodilla , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/complicaciones , Dimensión del Dolor , Tiempo de Reacción/fisiología , Encuestas y Cuestionarios , Adulto Joven
14.
Arch Virol ; 157(11): 2095-104, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22791111

RESUMEN

The severe acute respiratory syndrome coronavirus (SARS-CoV) RNA genome is replicated by a virus-encoded RNA replicase, the key component of which is the nonstructural protein 12 (nsp12). In this report, we describe the biochemical properties of a full-length recombinant SARS-CoV nsp12 RNA-dependent RNA polymerase (RdRp) capable of copying viral RNA templates. The purified SARS-CoV nsp12 showed both primer-dependent and primer-independent RNA synthesis activities using homopolymeric RNA templates. The RdRp activity was strictly dependent on Mn(2+). The nsp12 preferentially copied homopolymeric pyrimidine RNA templates in the absence of an added oligonucleotide primer. It was also able to initiate de novo RNA synthesis from the 3'-ends of both the plus- and minus-strand genome of SARS-CoV, using the 3'-terminal 36- and 37-nt RNA, respectively. The in vitro RdRp assay system established with a full-length nsp12 will be useful for understanding the mechanisms of coronavirus replication and for the development of anti-SARS-CoV agents.


Asunto(s)
ARN Viral/metabolismo , ARN Polimerasa Dependiente del ARN/metabolismo , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/enzimología , Regiones no Traducidas 3' , Cationes Bivalentes/metabolismo , Coenzimas/metabolismo , Cartilla de ADN/genética , Genoma Viral , Manganeso/metabolismo , ARN Polimerasa Dependiente del ARN/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/genética
15.
Nat Commun ; 13(1): 6755, 2022 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-36347869

RESUMEN

Human beings are made of ~50 trillion cells which arise from serial mitotic divisions of a single cell - the fertilised egg. Remarkably, the early human embryo is often chromosomally abnormal, and many are mosaic, with the karyotype differing from one cell to another. Mosaicism presumably arises from chromosome segregation errors during the early mitotic divisions, although these events have never been visualised in living human embryos. Here, we establish live cell imaging of chromosome segregation using normally fertilised embryos from an egg-share-to-research programme, as well as embryos deselected during fertility treatment. We reveal that the first mitotic division has an extended prometaphase/metaphase and exhibits phenotypes that can cause nondisjunction. These included multipolar chromosome segregations and lagging chromosomes that lead to formation of micronuclei. Analysis of nuclear number and size provides evidence of equivalent phenotypes in 2-cell human embryos that gave rise to live births. Together this shows that errors in the first mitotic division can be tolerated in human embryos and uncovers cell biological events that contribute to preimplantation mosaicism.


Asunto(s)
Segregación Cromosómica , Embrión de Mamíferos , Humanos , Mosaicismo , Metafase , Cariotipo , Blastocisto , Aneuploidia
16.
BMJ Open ; 12(7): e057790, 2022 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-35790326

RESUMEN

INTRODUCTION: The REFORM (REhabilitation FOR Musculoskeletal conditions) trial is a non-inferiority randomised controlled trial (n=210) designed to determine whether a supported home exercise programme is as good or better than a course of face-to-face physiotherapy for the management of some musculoskeletal conditions. The trial is currently being conducted across Sydney government hospitals in Australia. This process evaluation will run alongside the REFORM trial. It combines qualitative and quantitative data to help explain the trial results and determine the feasibility of rolling out supported home exercise programmes in settings similar to the REFORM trial. METHODS AND ANALYSIS: Two theoretical frameworks underpin our process evaluation methodology: the Realist framework (context, mechanism, outcomes) considers the causal assumptions as to why a supported home exercise programme may be as good or better than face-to-face physiotherapy in terms of the context, mechanisms and outcomes of the trial. The RE-AIM framework describes the Reach, Effectiveness, Adoption, Implementation and Maintenance of the intervention. These two frameworks will be broadly used to guide this process evaluation using a mixed-methods approach. For example, qualitative data will be derived from interviews with patients, healthcare professionals and stakeholders, and quantitative data will be collected to determine the cost and feasibility of providing supported home exercise programmes. These data will be analysed iteratively before the analysis of the trial results and will be triangulated with the results of the primary and secondary outcomes. ETHICS AND DISSEMINATION: This trial will be conducted in accordance with the National Health and Medical Research Council National Statement on Ethical Conduct in Human Research (2018) and the Note for Good Clinical Practice (CPMP/ICH-135/95). Ethical approval was obtained on 17 March 2017 from the Northern Sydney Local Health District Human Research Ethics Committee (trial number: HREC/16HAWKE/431-RESP/16/287) with an amendment for the process evaluation approved on 4 February 2020. The results of the process evaluation will be disseminated through publications in peer-reviewed journals and presentations at scientific conferences. TRIAL REGISTRATION NUMBER: ACTRN12619000065190.


Asunto(s)
Terapia por Ejercicio , Enfermedades Musculoesqueléticas , Atención Ambulatoria , Australia , Terapia por Ejercicio/métodos , Estudios de Factibilidad , Humanos , Enfermedades Musculoesqueléticas/rehabilitación , Evaluación de Programas y Proyectos de Salud , Ensayos Clínicos Controlados Aleatorios como Asunto , Autocuidado
17.
J Virol ; 84(9): 4330-40, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20164235

RESUMEN

In retroviruses and the double-stranded RNA totiviruses, the efficiency of programmed -1 ribosomal frameshifting is critical for ensuring the proper ratios of upstream-encoded capsid proteins to downstream-encoded replicase enzymes. The genomic organizations of many other frameshifting viruses, including the coronaviruses, are very different, in that their upstream open reading frames encode nonstructural proteins, the frameshift-dependent downstream open reading frames encode enzymes involved in transcription and replication, and their structural proteins are encoded by subgenomic mRNAs. The biological significance of frameshifting efficiency and how the relative ratios of proteins encoded by the upstream and downstream open reading frames affect virus propagation has not been explored before. Here, three different strategies were employed to test the hypothesis that the -1 PRF signals of coronaviruses have evolved to produce the correct ratios of upstream- to downstream-encoded proteins. Specifically, infectious clones of the severe acute respiratory syndrome (SARS)-associated coronavirus harboring mutations that lower frameshift efficiency decreased infectivity by >4 orders of magnitude. Second, a series of frameshift-promoting mRNA pseudoknot mutants was employed to demonstrate that the frameshift signals of the SARS-associated coronavirus and mouse hepatitis virus have evolved to promote optimal frameshift efficiencies. Finally, we show that a previously described frameshift attenuator element does not actually affect frameshifting per se but rather serves to limit the fraction of ribosomes available for frameshifting. The findings of these analyses all support a "golden mean" model in which viruses use both programmed ribosomal frameshifting and translational attenuation to control the relative ratios of their encoded proteins.


Asunto(s)
Regulación Viral de la Expresión Génica , Virus de la Hepatitis Murina/fisiología , Biosíntesis de Proteínas , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/fisiología , Proteínas Virales/biosíntesis , Animales , Sistema de Lectura Ribosómico , Modelos Moleculares , Virus de la Hepatitis Murina/genética , Virus de la Hepatitis Murina/crecimiento & desarrollo , Virus de la Hepatitis Murina/patogenicidad , Mutación , Conformación de Ácido Nucleico , Sistemas de Lectura Abierta , ARN Viral/genética , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/genética , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/crecimiento & desarrollo , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/patogenicidad
18.
Elife ; 102021 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-34487490

RESUMEN

Decidual remodelling of midluteal endometrium leads to a short implantation window after which the uterine mucosa either breaks down or is transformed into a robust matrix that accommodates the placenta throughout pregnancy. To gain insights into the underlying mechanisms, we established and characterized endometrial assembloids, consisting of gland-like organoids and primary stromal cells. Single-cell transcriptomics revealed that decidualized assembloids closely resemble midluteal endometrium, harbouring differentiated and senescent subpopulations in both glands and stroma. We show that acute senescence in glandular epithelium drives secretion of multiple canonical implantation factors, whereas in the stroma it calibrates the emergence of anti-inflammatory decidual cells and pro-inflammatory senescent decidual cells. Pharmacological inhibition of stress responses in pre-decidual cells accelerated decidualization by eliminating the emergence of senescent decidual cells. In co-culture experiments, accelerated decidualization resulted in entrapment of collapsed human blastocysts in a robust, static decidual matrix. By contrast, the presence of senescent decidual cells created a dynamic implantation environment, enabling embryo expansion and attachment, although their persistence led to gradual disintegration of assembloids. Our findings suggest that decidual senescence controls endometrial fate decisions at implantation and highlight how endometrial assembloids may accelerate the discovery of new treatments to prevent reproductive failure.


At the beginning of a human pregnancy, the embryo implants into the uterus lining, known as the endometrium. At this point, the endometrium transforms into a new tissue that helps the placenta to form. Problems in this transformation process are linked to pregnancy disorders, many of which can lead to implantation failure (the embryo fails to invade the endometrium altogether) or recurrent miscarriages (the embryo implants successfully, but the interface between the placenta and the endometrium subsequently breaks down). Studying the implantation of human embryos directly is difficult due to ethical and technical barriers, and animals do not perfectly mimic the human process, making it challenging to determine the causes of pregnancy disorders. However, it is likely that a form of cellular arrest called senescence, in which cells stop dividing but remain metabolically active, plays a role. Indeed, excessive senescence in the cells that make up the endometrium is associated with recurrent miscarriage, while a lack of senescence is associated with implantation failure. To study this process, Rawlings et al. developed a new laboratory model of the human endometrium by assembling two of the main cell types found in the tissue into a three-dimensional structure. When treated with hormones, these 'assembloids' successfully mimic the activity of genes in the cells of the endometrium during implantation. Rawlings et al. then exposed the assembloids to the drug dasatinib, which targets and eliminates senescent cells. This experiment showed that assembloids become very robust and static when devoid of senescent cells. Rawlings et al. then studied the interaction between embryos and assembloids using time-lapse imaging. In the absence of dasatinib treatment, cells in the assembloid migrated towards the embryo as it expanded, a process required for implantation. However, when senescent cells were eliminated using dasatinib, this movement of cells towards the embryo stopped, and the embryo failed to expand, in a situation that mimicks implantation failure. The assembloid model of the endometrium may help scientists to study endometrial defects in the lab and test potential treatments. Further work will include other endometrial cell types in the assembloids, and could help increase the reliability of the model. However, any drug treatments identified using this model will need further research into their safety and effectiveness before they can be offered to patients.


Asunto(s)
Senescencia Celular , Implantación del Embrión/fisiología , Endometrio/citología , Células del Estroma/citología , Técnicas de Cocultivo , Decidua/fisiología , Femenino , Humanos , Organoides , Embarazo
19.
Arch Rehabil Res Clin Transl ; 3(2): 100128, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34179764

RESUMEN

OBJECTIVE: To develop a bank of text messages for a lifestyle-based self-management intervention for people with low back pain (LBP). DESIGN: Iterative development process. SETTING: Community and primary care. PARTICIPANTS: Fifteen researchers, clinicians, and consumer representatives participated in the concept and initial content development phase. Twelve experts (researchers and clinicians) and 12 consumers participated in the experts and consumers review phase. Full study sample of participants was N=39. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: We first conducted two 2-hour workshops to identify important domains for people with LBP, sources of content, appropriate volume, and timing of the messages. The messages were then drafted by a team of writers. Second, we invited expert researchers and clinicians to review and score the messages using a 5-item psychometric scale according to (1) the appropriateness of the content and (2) the likelihood of clinical effectiveness and to provide written feedback. Messages scoring ≤8 out of 10 points would be modified accordingly. Consumers were invited to review the messages and score them using a 5-item psychometric scale according to the utility of the content, the understanding of the content, and language acceptability and to provide feedback. Messages scoring ≤12 out of 15 points would be improved. RESULTS: Exercise, education, mood, sleep, use of care, and medication domains were identified and 82 domain-specific evidence-based messages were written. Messages received a mean score of 8.3 out of 10 points by experts. Twenty-nine messages were modified accordingly. The mean score of the messages based on consumers feedback was of 12.5 out of 15 points. Thirty-six messages were improved. CONCLUSIONS: We developed a bank of text messages for an evidence-based self-management intervention using a theory-based, iterative, codesign process with researchers, consumers, and clinicians. This article provides scientific support for future development of text message interventions within the pain field.

20.
BMJ Open ; 11(5): e041242, 2021 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-34006536

RESUMEN

INTRODUCTION: Exercise, support and advice are considered core components of management for most musculoskeletal conditions and are typically provided by physiotherapists through regular face-to-face treatments. However, exercise can be provided remotely as part of a home exercise programme, while support and advice can be provided over the telephone. There is initial evidence from trials and systematic reviews to suggest that remotely provided physiotherapy can be used to manage a variety of musculoskeletal conditions safely and effectively. METHODS AND ANALYSIS: The aim of this single-blind randomised controlled non-inferiority trial is to determine whether a supported home exercise programme is as good as or better than face-to-face physiotherapy for the treatment of musculoskeletal conditions. Two hundred and ten participants will be recruited from five public hospitals in Sydney, Australia. Participants will be randomised to either the supported home exercise group or the face-to-face physiotherapy group. Participants allocated to the supported home exercise group will initially receive one face-to-face session with the trial physiotherapist and will then be managed remotely for the next 6 weeks. Participants allocated to the face-to-face physiotherapy group will receive a course of physiotherapy as typically provided in Sydney government hospitals. The primary outcome is function measured by the Patient Specific Functional Scale at 6 weeks. There will be nine secondary outcomes measured at 6 and 26 weeks. Separate analyses will be conducted on each outcome, and all analyses will be conducted on an intention-to-treat basis. A health economic evaluation will be conducted from a health funder plus patient perspective. ETHICS AND DISSEMINATION: Ethical approval was obtained on the 17 March 2017 from the Northern Sydney Local Health District HREC, trial number HREC/16HAWKE/431-RESP/16/287. The results of this study will be submitted for publication to peer-reviewed journals and be presented at national and international conferences. Recruitment commenced in March 2019, and it is anticipated that the trial will be completed by December 2021. This trial will investigate two different models of physiotherapy care for people with musculoskeletal conditions. TRIAL REGISTRATION NUMBER: CPMP/ICH-135/95. PROTOCOL VERSION: The most recent version of the protocol is V.1.2 dated November 2019.


Asunto(s)
Terapia por Ejercicio , Fisioterapeutas , Australia , Humanos , Estudios Multicéntricos como Asunto , Modalidades de Fisioterapia , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Método Simple Ciego , Resultado del Tratamiento
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