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1.
J Digit Imaging ; 36(1): 365-372, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36171520

RESUMO

We describe the curation, annotation methodology, and characteristics of the dataset used in an artificial intelligence challenge for detection and localization of COVID-19 on chest radiographs. The chest radiographs were annotated by an international group of radiologists into four mutually exclusive categories, including "typical," "indeterminate," and "atypical appearance" for COVID-19, or "negative for pneumonia," adapted from previously published guidelines, and bounding boxes were placed on airspace opacities. This dataset and respective annotations are available to researchers for academic and noncommercial use.


Assuntos
COVID-19 , Humanos , Inteligência Artificial , Radiografia , Aprendizado de Máquina , Radiologistas , Radiografia Torácica/métodos
2.
Gene Ther ; 21(3): 272-81, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24430237

RESUMO

Corneal graft rejection is a major problem in chronic herpetic keratitis (HK) patients with latent infection. A new class of antiviral agents targeting latent and active forms of herpes simplex virus type 1 (HSV-1) is importantly required. Meganucleases are sequence-specific homing endonucleases capable of inducing DNA double-strand breaks. A proof-of-concept experiment has shown that tailor-made meganucleases are efficient against HSV-1 in vitro. To take this work a step forward, we hypothesized that the pre-treatment of human corneas in eye banks using meganuclease-encoding vectors will allow HK patients to receive a medicated cornea to resist the recurrence of the infection and the common graft rejection problem. However, this strategy requires efficient gene delivery to human corneal endothelium. Using recombinant adeno-associated virus, serotype 2/1 (rAAV2/1), efficient gene delivery of a reporter gene was demonstrated in human corneas ex vivo. The optimum viral dose was 3.7 × 10(11) VG with an exposure time of 1 day, followed by 6 days incubation in de-swelling medium. In addition, 12 days incubation can result in transgene expression in excess of 70%. Using similar transduction conditions, meganuclease transgene expression was detected in 39.4% of the endothelial cells after 2 weeks in culture. Reduction of the total viral load in the media and the endothelial cells of corneas infected with HSV-1 was shown. Collectively, this work provides information about the optimum conditions to deliver genetic material to the cornea, and demonstrates for the first time the expression of meganuclease in human corneas ex vivo and its antiviral activity. In conclusion, we demonstrate that the treatment of human corneas in eye banks before transplantation is a new approach to address the unmet clinical needs in corneal diseases.


Assuntos
Córnea/metabolismo , Desoxirribonuclease I/genética , Proteínas Virais/genética , Desoxirribonuclease I/metabolismo , Dependovirus/genética , Dependovirus/metabolismo , Técnicas de Transferência de Genes , Genes Reporter/genética , Herpesvirus Humano 1/enzimologia , Humanos , Técnicas In Vitro , Proteínas Virais/metabolismo
4.
Ann R Coll Surg Engl ; 106(4): 377-384, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37843132

RESUMO

INTRODUCTION: Inhalation of foreign bodies represents a potentially fatal emergency in both adults and children. Chest x-ray, in isolation, is neither sensitive nor specific. Rigid bronchoscopy represents the gold standard to diagnose and retrieve paediatric foreign bodies. Cases are encountered infrequently, creating anxieties about their management. Little is known about the confidence in, and maintenance of, rigid bronchoscopy skills by ear, nose and throat teams. METHODS: A 15-question survey was completed by 50 practising otolaryngology consultants in England. RESULTS: Results show that almost 40% of otolaryngology consultants covering rigid bronchoscopy have not performed bronchoscopy in more than 5 years. Consultants raised concerns about the anaesthetic support and the speed of equipment assembly. Questions on clinical practice showed disparities in practice in the same scenario. CONCLUSIONS: The authors advocate addressing many of the issues raised by the study with a greater availability of simulation courses and regular scheduled intradepartmental teaching days for all professionals involved. National guidelines on criteria for transfer to tertiary centres would improve the consistency of practice.


Assuntos
Corpos Estranhos , Otolaringologia , Criança , Humanos , Lactente , Broncoscopia/métodos , Consultores , Inquéritos e Questionários , Corpos Estranhos/diagnóstico , Estudos Retrospectivos
5.
Int Urogynecol J ; 24(6): 1053-5, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22825417

RESUMO

Large fasciomuscular damage of the feminine pelvic floor resulting in pelvic organ prolapse constitutes a challenge for surgical reconstruction.Between 2005 and 2010, ten women aged 47-75 years were treated by abdominoperineal implantation of polypropylene mesh for modified sacral perineocolporectopexy and subsequently followed up. They were suffering from enterocele (9), genital prolapse (8), descending perineum (5), rectal prolapse (4), and rectocele (3). Five women were incontinent (mean Wexner 9) and six had incomplete rectal evacuation. Defecography revealed enterocele III (5) and II (4). Magnetic resonance (MR) diagnosed descending perineum in five patients (mean 3.8 cm).Permanent reconstruction of the pelvic floor and remission of organ prolapse was achieved at 12-months of follow-up in all except one patient. There were two small vaginal mesh erosions and one hematoma within the pelvic floor. Improvement at rectal emptying and anal incontinence (mean Wexner 4) were found.Modified sacral perineocolporectopexy is effective in the treatment of complex pelvic floor anatomical defects and organ prolapse. Improvements in rectal emptying, pelvic feeling of heaviness, and dyspareunia were achieved. The procedure was safe and characterized by good implant tolerance and a low rate of complications.


Assuntos
Colposcopia/efeitos adversos , Procedimentos Cirúrgicos em Ginecologia/efeitos adversos , Prolapso de Órgão Pélvico/cirurgia , Telas Cirúrgicas/efeitos adversos , Incontinência Urinária/cirurgia , Remoção de Dispositivo , Feminino , Humanos , Pessoa de Meia-Idade , Retocele/cirurgia , Resultado do Tratamento , Vagina/cirurgia
6.
Int Urogynecol J ; 24(7): 1091-103, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23632798

RESUMO

INTRODUCTION AND HYPOTHESIS: The objective of this study was to create a valid, reliable, and responsive sexual function measure in women with pelvic floor disorders (PFDs) for both sexually active (SA) and inactive (NSA) women. METHODS: Expert review identified concept gaps and generated items evaluated with cognitive interviews. Women underwent Pelvic Organ Prolapse Quantification (POPQ) exams and completed the Incontinence Severity Index (ISI), a prolapse question from the Epidemiology of Prolapse and Incontinence Questionnaire (ISI scores), the Pelvic Floor Distress Inventory-20 (PFDI-20), and the Female Sexual Function Index (FSFI). Principle components and orthogonal varimax rotation and principle factor analysis with oblique rotation identified item grouping. Cronbach's alpha measured internal consistency. Factor correlations evaluated criterion validation. Change scores compared to change scores in other measures evaluated responsiveness among women who underwent surgery. RESULTS: A total of 589 women gave baseline data, 200 returned surveys after treatment, and 147 provided test-retest data. For SA women, 3 subscales each in 2 domains (21 items) and for NSA women 2 subscales in each of 2 domains (12 items) emerged with robust psychometric properties. Cronbach's alpha ranged from .63 to .91. For SA women, correlations were in the anticipated direction with PFDI-20, ISI, and FSFI scores, POPQ, and EPIQ question #35 (all p < .05). PFDI-20, ISI, and FSFI subscale change scores correlated with Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire International Urogynecological Association-revised (PISQ-IR) factor change scores and with mean change scores in women who underwent surgery (all p < .05). For NSA women, PISQ-IR scores correlated with PFDI-20, ISI scores, and with EPIQ question #35 (all p < .05). No items demonstrated differences between test and retest (all p ≥ .05), indicating stability over time. CONCLUSIONS: The PISQ-IR is a valid, reliable, and responsive measure of sexual function.


Assuntos
Distúrbios do Assoalho Pélvico/complicações , Prolapso de Órgão Pélvico/complicações , Disfunções Sexuais Fisiológicas/diagnóstico , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Psicometria , Reprodutibilidade dos Testes , Disfunções Sexuais Fisiológicas/etiologia , Inquéritos e Questionários
7.
Int Urogynecol J ; 23(5): 579-84, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22083515

RESUMO

INTRODUCTION AND HYPOTHESIS: This study was conducted to determine the differences in the inter-observer agreement of the simplified Pelvic Organ Prolapse Quantification (POP-Q) system from center to center in a large international multicenter study. METHODS: This is a secondary analysis of the results of a large prospective single blind multicenter trial studying the inter-observer agreement of a simplified POP-Q exam. Twelve centers from four continents with a total of 511 subjects were included in this study. The number of subjects recruited per center ranged from 20 to 81. Each patient was independently examined by two investigators, with examination order randomly assigned and investigators blinded to each other's result. The weighted kappa statistic was used to evaluate the inter-observer agreement. RESULTS: Good and significant associations were observed on the anterior, posterior, and apical segments. Six out of 11 sites did not provide adequate number of subjects with prior hysterectomy for weighted kappa statistics or achieve significance regarding vaginal cuff measurement. CONCLUSIONS: The simplified POP-Q demonstrated good inter-examiner agreement across multiple centers.


Assuntos
Prolapso de Órgão Pélvico/diagnóstico , Prolapso de Órgão Pélvico/epidemiologia , Exame Físico/métodos , Idoso , Feminino , Humanos , Cooperação Internacional , Pessoa de Meia-Idade , Variações Dependentes do Observador , Prevalência , Estudos Prospectivos , Reprodutibilidade dos Testes , Método Simples-Cego
8.
Ergonomics ; 54(9): 792-805, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21867372

RESUMO

The use of multimodal (speech plus manual) control of the sensors on combinations of one, two, three or five simulated unmanned vehicles (UVs) is explored. Novice controllers of simulated UVs complete a series of target checking tasks. Two experiments compare speech and gamepad control for one, two, three or five UVs in a simulated environment. Increasing the number of UVs has an impact on subjective rating of workload (measured by NASA-Task Load Index), particularly when moving from one to three UVs. Objective measures of performance showed that the participants tended to issue fewer commands as the number of vehicles increased (when using the gamepad control), but, while performance with a single UV was superior to that of multiple UVs, there was little difference across two, three or five UVs. Participants with low spatial ability (measured by the Object Perspectives Test) showed an increase in time to respond to warnings when controlling five UVs. Combining speech with gamepad control of sensors on UVs leads to superior performance on a secondary (respond-to-warnings) task (implying a reduction in demand) and use of fewer commands on primary (move-sensors and classify-target) tasks (implying more efficient operation). STATEMENT OF RELEVANCE: Benefits of multimodal control for unmanned vehicles are demonstrated. When controlling sensors on multiple UVs, participants with low spatial orientation scores have problems. It is proposed that the findings of these studies have implications for selection of UV operators and suggests that future UV workstations could benefit from multimodal control.


Assuntos
Automação , Interface para o Reconhecimento da Fala , Análise e Desempenho de Tarefas , Interface Usuário-Computador , Adulto , Simulação por Computador , Desenho de Equipamento , Feminino , Humanos , Masculino , Veículos Automotores , Segurança , Carga de Trabalho , Adulto Jovem
9.
AJNR Am J Neuroradiol ; 41(9): 1690-1697, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32816774

RESUMO

BACKGROUND AND PURPOSE: Parathyroid gland weight is a clinically relevant parameter used to diagnose parathyroid adenomas intraoperatively. We evaluated the accuracy of a formula to estimate parathyroid weight on preoperative 4D-CT. MATERIALS AND METHODS: A single-institution retrospective study was performed in patients with primary hyperparathyroidism who underwent 4D-CT between January 2013 and December 2014 with subsequent parathyroidectomy and surgical cure. All patients had correct localization of a solitary parathyroid adenoma. The longest 3 dimensions of all identified parathyroid glands were measured on CT, and weight was estimated using the formula: weight4D-CT (mg) = 1 mg/mm3 × Length (mm) × Width (mm) × Height (mm) × π/6. We correlated weight4D-CT with pathology specimen weight (weightpathology). Using receiver operating characteristic analysis, we estimated the performance of weight4D-CT to discriminate a parathyroid adenoma from normal glands on 4D-CT and determined the optimal threshold based on the Youden index. RESULTS: One hundred sixteen patients (85 women, 31 men) were evaluated. Weight4D-CT was shown to be strongly correlated with weightpathology as demonstrated by Spearman ρ = 0.73 (P < .01), concordance correlation coefficient = 0.92 (95% CI, 0.89-0.94), and Cronbach α = 0.96. The performance of weight4D-CT for the diagnosis of parathyroid adenoma was excellent, with an area under the curve of 0.955 (95% CI, 0.925-0.985; P < .001). Based on the Youden index, the optimal threshold was >50 mg, with a sensitivity of 96.7% and a specificity of 95.7%. CONCLUSIONS: Radiologists can accurately estimate parathyroid adenoma weight on 4D-CT. This metric is highly correlated with pathologic weight, and a threshold cutoff of >50 mg can be used to distinguish parathyroid adenoma from normal glands.


Assuntos
Adenoma/diagnóstico por imagem , Algoritmos , Tomografia Computadorizada Quadridimensional/métodos , Hiperparatireoidismo Primário/complicações , Neoplasias das Paratireoides/diagnóstico por imagem , Adenoma/complicações , Adenoma/patologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Neoplasias das Paratireoides/complicações , Neoplasias das Paratireoides/patologia , Curva ROC , Estudos Retrospectivos
10.
FEMS Microbiol Lett ; 73(1-2): 69-74, 1992 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-1521774

RESUMO

Three strains of Peptostreptococcus productus were tested for growth at the expense of methoxylated aromatic compounds. Strain M8A-18 (human fecal isolate) was unable to utilize methoxylated aromatic compounds. While the type strain ATCC 27340 (human septicemia isolate) was capable of minimal growth with methoxylated aromatic compounds, ATCC 35244 (sewage sludge isolate) displayed significant growth on methoxylated aromatic compounds. Methoxylated phenols, benzoates, benzyl alcohol and phenylacrylates supported the growth of ATCC 35244 and were O-demethylated to their respective hydroxylated derivatives. During O-methyl- or CO-dependent growth, the double bond of the acrylate side chain of certain methoxylated and non-methoxylated phenylacrylates was reduced. Although other aromatic substituent groups (-COOH and -CH3) were transformed during CO-dependent growth, in short-term growth studies, the aromatic ring was not subject to reduction or degradation. Of the three strains tested, only strain M8A-18 failed to grow at the expense of carbon monoxide (CO).


Assuntos
Peptostreptococcus/metabolismo , Acrilatos/metabolismo , Benzoatos/metabolismo , Álcoois Benzílicos/metabolismo , Biotransformação , Peptostreptococcus/crescimento & desenvolvimento , Fenóis/metabolismo
11.
J Ophthalmol ; 2013: 670947, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24069532

RESUMO

Aims. To compare HB&L and BACTEC systems for detecting the microorganisms contaminating the corneal storage liquid preserved at 31°C. Methods. Human donor corneas were stored at 4°C followed by preservation at 31°C. Samples of the storage medium were inoculated in BACTEC Peds Plus/F (aerobic microorganisms), BACTEC Plus Anaerobic/F (anaerobic microorganisms), and HB&L bottles. The tests were performed (a) after six days of storage, (b) end of storage, and (c) after 24 hours of preservation in deturgescent liquid sequentially. 10,655 storage and deturgescent media samples were subjected to microbiological control using BACTEC (6-day incubation) and HB&L (24-hour incubation) systems simultaneously. BACTEC positive/negative refers to both/either aerobic and anaerobic positives/negatives, whereas HB&L can only detect the aerobic microbes, and therefore the positives/negatives depend on the presence/absence of aerobic microorganisms. Results. 147 (1.38%) samples were identified positive with at least one of the two methods. 127 samples (134 identified microorganisms) were positive with both HB&L and BACTEC. 14 HB&L+/BACTEC- and 6 BACTEC+/HB&L- were identified. Sensitivity (95.5%), specificity (99.8%), and positive (90.1%) and negative predictive values (99.9%) were high with HB&L considering a 3.5% annual contamination rate. Conclusion. HB&L is a rapid system for detecting microorganisms in corneal storage medium in addition to the existing methods.

18.
Aliment Pharmacol Ther ; 27(8): 697-712, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18248653

RESUMO

BACKGROUND: Colorectal cancer screening and treatment are rapidly evolving. Aims To reappraise stool-based colorectal cancer screening in light of changing test performance characteristics, lower test cost and increasing colorectal cancer care costs. METHODS: Using a Markov model, we compared faecal DNA testing every 3 years, annual faecal occult blood testing or immunochemical testing, and colonoscopy every 10 years. RESULTS: In the base case, faecal occult blood testing and faecal immunochemical testing gained life-years/person and cost less than no screening. Faecal DNA testing version 1.1 at $300 (the current PreGen Plus test) gained 5323 life-years/100 000 persons at $16 900/life-year gained and faecal DNA testing version 2 (enhanced test) gained 5795 life-years/100 000 persons at $15 700/life-year gained vs. no screening. In the base case and most sensitivity analyses, faecal occult blood testing and faecal immunochemical testing were preferred to faecal DNA testing. Faecal DNA testing version 2 cost $100 000/life-year gained vs. faecal immunochemical testing when per-cycle adherence with faecal immunochemical testing was 22%. Faecal immunochemical testing with excellent adherence was superior to colonoscopy every 10 years. CONCLUSIONS: As novel biological therapies increase colorectal cancer treatment costs, faecal occult blood testing and faecal immunochemical testing could become cost-saving. The cost-effectiveness of faecal DNA testing compared with no screening has improved, but faecal occult blood testing and faecal immunochemical testing are preferred to faecal DNA testing when patient adherence is high. Faecal immunochemical testing may be comparable to colonoscopy every 10 years in persons adhering to yearly testing.


Assuntos
Neoplasias Colorretais/economia , Fezes/química , Programas de Rastreamento/métodos , Colonoscopia/economia , Neoplasias Colorretais/diagnóstico , Análise Custo-Benefício , Humanos , Cadeias de Markov , Programas de Rastreamento/economia , Sangue Oculto , Anos de Vida Ajustados por Qualidade de Vida
19.
Neurobiol Aging ; 28(10): 1493-506, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16904243

RESUMO

Aged individuals with Down syndrome (DS) develop Alzheimer's disease (AD) neuropathology by the age of 40 years. The purpose of the current study was to measure age-associated changes in APP processing in 36 individuals with DS (5 months-69 years) and in 26 controls (5 months-100 years). Alpha-secretase significantly decreased with age in DS, particularly in cases over the age of 40 years and was stable in controls. The levels of C-terminal fragments of APP reflecting alpha-secretase processing (CTF-alpha) decreased with age in both groups. In both groups, there was significant increase in beta-secretase activity with age. CTF-beta remained constant with age in controls suggesting compensatory increases in turnover/clearance mechanisms. In DS, young individuals had the lowest CTF-beta levels that may reflect rapid conversion of beta-amyloid (Abeta) to soluble pools or efficient CTF-beta clearance mechanisms. Treatments to slow or prevent AD in the general population targeting secretase activity may be more efficacious in adults with DS if combined with approaches that enhance Abeta degradation and clearance.


Assuntos
Envelhecimento/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/biossíntese , Precursor de Proteína beta-Amiloide/metabolismo , Encéfalo/enzimologia , Síndrome de Down/enzimologia , Adolescente , Adulto , Idoso , Envelhecimento/patologia , Biomarcadores/metabolismo , Encéfalo/patologia , Encéfalo/fisiopatologia , Criança , Pré-Escolar , Progressão da Doença , Síndrome de Down/patologia , Síndrome de Down/fisiopatologia , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Placa Amiloide/enzimologia , Placa Amiloide/patologia , Valores de Referência , Regulação para Cima/fisiologia
20.
Sex Transm Dis ; 14(4): 221-6, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3125616

RESUMO

Some human urine is bactericidal for the F-62 strain of Neisseria gonorrhoeae. Gonococci of three auxotypes (Pro-; Arg-, Hyx-, Ura-; and Pro-, Arg-. (Orn*), Ura-) were tested by in-vitro exposure to 31 samples of urine from 14 men. Nineteen of the urine specimens were bactericidal, and 12 were not. Except for one sample, all cidal urines came from five men. Cidal activity was associated with acidic, concentrated urines; it was unaffected by exposure to lowered pH, pronase, heat or cold, and was dialyzable with use of a dialysis membrane with a cut-off molecular weight of 1000. Neutralization of the acid urines removed the antigonococcal activity. Noncidal acid urines became cidal urines when concentrated by lyophilization. Zinc, lysozyme, fluoride ions, and fatty acids are substances that have antibacterial activity and are also present in urine. These substances were examined for antigonococcal activity. Neither zinc salts, fluoride ions, lysozyme, nor fatty acids in concentrations exceeding those found in urine were bactericidal for the gonococci. These results show that sufficiently concentrated, acidic urines kill gonococci by an unknown mechanism.


Assuntos
Neisseria gonorrhoeae/imunologia , Urina/análise , Diálise , Ácidos Graxos/urina , Fluoretos/urina , Humanos , Concentração de Íons de Hidrogênio , Masculino , Muramidase/urina , Pronase/urina , Zinco/urina
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