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1.
AJNR Am J Neuroradiol ; 43(10): 1494-1499, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36137666

RESUMO

BACKGROUND AND PURPOSE: Distribution of intracranial hemorrhage in term and late-preterm neonates is relatively unexplored. This descriptive study examines the MR imaging-detectable spectrum of intracranial hemorrhage in this population and potential risk factors. MATERIALS AND METHODS: Prevalence and distribution of intracranial hemorrhage in consecutive term/late-preterm neonates who underwent brain MR imaging between January 2011 to August 2018 were assessed. MRIs were analyzed to determine intracranial hemorrhage distribution (intraventricular, subarachnoid, subdural, intraparenchymal, and subpial/leptomeningeal), and chart review was performed for potential clinical risk factors. RESULTS: Of 725 term/late-preterm neonates who underwent brain MR imaging, intracranial hemorrhage occurred in 63 (9%). Fifty-two (83%) had multicompartment intracranial hemorrhage. Intraventricular and subdural were the most common hemorrhage locations, found in 41 (65%) and 39 (62%) neonates, respectively. Intraparenchymal hemorrhage occurred in 33 (52%); subpial, in 19 (30%); subarachnoid, in 12 (19%); and epidural, in 2 (3%) neonates. Twenty infants (32%) were delivered via cesarean delivery, and 5 (8%), via instrumented delivery. Cortical vein thromboses were present in 34 (54%); periventricular or medullary vein thromboses, in 37 (59%); and cerebral venous sinus thrombosis, in 5 (8%). Thirty-seven (59%) had elevated markers of coagulopathy (international normalized ratio > 1.2, fibrinogen level < 234), 9 (14%) had a clinically meaningful elevation in the international normalized ratio (>1.4), and 3 (5%) had a clinically meaningful decrease in the fibrinogen level (<150). Three (5%) neonates had thrombocytopenia (platelet count < 100 × 103/µL). CONCLUSIONS: While relatively infrequent, there was a wide distribution of intracranial hemorrhage in term and late-preterm infants; intraventricular and subdural hemorrhages were the most common types. We report a high prevalence of venous congestion or thromboses accompanying neonatal intracranial hemorrhage.


Assuntos
Doenças do Recém-Nascido , Recém-Nascido Prematuro , Hemorragias Intracranianas , Feminino , Humanos , Recém-Nascido , Gravidez , Encéfalo/diagnóstico por imagem , Hemorragia Cerebral/etiologia , Fibrinogênio , Hematoma Subdural/complicações , Hemorragias Intracranianas/diagnóstico por imagem , Hemorragias Intracranianas/epidemiologia , Imageamento por Ressonância Magnética
2.
Clin Radiol ; 77(9): 717-718, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35732570
3.
AJNR Am J Neuroradiol ; 41(9): 1718-1725, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32816765

RESUMO

BACKGROUND AND PURPOSE: Posterior fossa tumors are the most common pediatric brain tumors. MR imaging is key to tumor detection, diagnosis, and therapy guidance. We sought to develop an MR imaging-based deep learning model for posterior fossa tumor detection and tumor pathology classification. MATERIALS AND METHODS: The study cohort comprised 617 children (median age, 92 months; 56% males) from 5 pediatric institutions with posterior fossa tumors: diffuse midline glioma of the pons (n = 122), medulloblastoma (n = 272), pilocytic astrocytoma (n = 135), and ependymoma (n = 88). There were 199 controls. Tumor histology served as ground truth except for diffuse midline glioma of the pons, which was primarily diagnosed by MR imaging. A modified ResNeXt-50-32x4d architecture served as the backbone for a multitask classifier model, using T2-weighted MRIs as input to detect the presence of tumor and predict tumor class. Deep learning model performance was compared against that of 4 radiologists. RESULTS: Model tumor detection accuracy exceeded an AUROC of 0.99 and was similar to that of 4 radiologists. Model tumor classification accuracy was 92% with an F1 score of 0.80. The model was most accurate at predicting diffuse midline glioma of the pons, followed by pilocytic astrocytoma and medulloblastoma. Ependymoma prediction was the least accurate. Tumor type classification accuracy and F1 score were higher than those of 2 of the 4 radiologists. CONCLUSIONS: We present a multi-institutional deep learning model for pediatric posterior fossa tumor detection and classification with the potential to augment and improve the accuracy of radiologic diagnosis.


Assuntos
Aprendizado Profundo , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias Infratentoriais/classificação , Neoplasias Infratentoriais/diagnóstico por imagem , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Neoplasias Infratentoriais/patologia , Imageamento por Ressonância Magnética/métodos , Masculino , Adulto Jovem
4.
AJNR Am J Neuroradiol ; 41(7): 1256-1262, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32586967

RESUMO

BACKGROUND AND PURPOSE: Conventional single-shot FSE commonly used for fast MRI may be suboptimal for brain evaluation due to poor image contrast, SNR, or image blurring. We investigated the clinical performance of variable refocusing flip angle single-shot FSE, a variation of single-shot FSE with lower radiofrequency energy deposition and potentially faster acquisition time, as an alternative approach to fast brain MR imaging. MATERIALS AND METHODS: We retrospectively compared half-Fourier single-shot FSE with half- and full-Fourier variable refocusing flip angle single-shot FSE in 30 children. Three readers reviewed images for motion artifacts, image sharpness at the brain-fluid interface, and image sharpness/tissue contrast at gray-white differentiation on a modified 5-point Likert scale. Two readers also evaluated full-Fourier variable refocusing flip angle single-shot FSE against T2-FSE for brain lesion detectability in 38 children. RESULTS: Variable refocusing flip angle single-shot FSE sequences showed more motion artifacts (P < .001). Variable refocusing flip angle single-shot FSE sequences scored higher regarding image sharpness at brain-fluid interfaces (P < .001) and gray-white differentiation (P < .001). Acquisition times for half- and full-Fourier variable refocusing flip angle single-shot FSE were faster than for single-shot FSE (P < .001) with a 53% and 47% reduction, respectively. Intermodality agreement between full-Fourier variable refocusing flip angle single-shot FSE and T2-FSE findings was near-perfect (κ = 0.90, κ = 0.95), with an 8% discordance rate for ground truth lesion detection. CONCLUSIONS: Variable refocusing flip angle single-shot FSE achieved 2× faster scan times than single-shot FSE with improved image sharpness at brain-fluid interfaces and gray-white differentiation. Such improvements are likely attributed to a combination of improved contrast, spatial resolution, SNR, and reduced T2-decay associated with blurring. While variable refocusing flip angle single-shot FSE may be a useful alternative to single-shot FSE and, potentially, T2-FSE when faster scan times are desired, motion artifacts were more common in variable refocusing flip angle single-shot FSE, and, thus, they remain an important consideration before clinical implementation.


Assuntos
Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Adolescente , Artefatos , Criança , Pré-Escolar , Feminino , Humanos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Fatores de Tempo
5.
AJNR Am J Neuroradiol ; 40(11): 1804-1810, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31694820

RESUMO

BACKGROUND AND PURPOSE: Diffuse midline gliomas with histone H3 K27M mutation are biologically aggressive tumors with poor prognosis defined as a new diagnostic entity in the 2016 World Health Organization Classification of Tumors of the Central Nervous System. There are no qualitative imaging differences (enhancement, border, or central necrosis) between histone H3 wildtype and H3 K27M-mutant diffuse midline gliomas. Herein, we evaluated the utility of diffusion-weighted imaging to distinguish H3 K27M-mutant from histone H3 wildtype diffuse midline gliomas. MATERIALS AND METHODS: We identified 31 pediatric patients (younger than 21 years of age) with diffuse gliomas centered in midline structures that had undergone assessment for histone H3 K27M mutation. We measured ADC within these tumors using a voxel-based 3D whole-tumor measurement method. RESULTS: Our cohort included 18 infratentorial and 13 supratentorial diffuse gliomas centered in midline structures. Twenty-three (74%) tumors carried H3-K27M mutations. There was no difference in ADC histogram parameters (mean, median, minimum, maximum, percentiles) between mutant and wild-type tumors. Subgroup analysis based on tumor location also did not identify a difference in histogram descriptive statistics. Patients who survived <1 year after diagnosis had lower median ADC (1.10 × 10-3mm2/s; 95% CI, 0.90-1.30) compared with patients who survived >1 year (1.46 × 10-3mm2/s; 95% CI, 1.19-1.67; P < .06). Average ADC values for diffuse midline gliomas were 1.28 × 10-3mm2/s (95% CI, 1.21-1.34) and 0.86 × 10-3mm2/s (95% CI, 0.69-1.01) for hemispheric glioblastomas with P < .05. CONCLUSIONS: Although no statistically significant difference in diffusion characteristics was found between H3-K27M mutant and H3 wildtype diffuse midline gliomas, lower diffusivity corresponds to a lower survival rate at 1 year after diagnosis. These findings can have an impact on the anticipated clinical course for this patient population and offer providers and families guidance on clinical outcomes.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Glioma/diagnóstico por imagem , Adolescente , Adulto , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Criança , Estudos de Coortes , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Glioma/genética , Glioma/patologia , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Masculino , Mutação , Adulto Jovem
6.
Sci Adv ; 5(1): eaau7126, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30662947

RESUMO

During the European Middle Ages, the opening of long-distance Asian trade routes introduced exotic goods, including ultramarine, a brilliant blue pigment produced from lapis lazuli stone mined only in Afghanistan. Rare and as expensive as gold, this pigment transformed the European color palette, but little is known about its early trade or use. Here, we report the discovery of lapis lazuli pigment preserved in the dental calculus of a religious woman in Germany radiocarbon-dated to the 11th or early 12th century. The early use of this pigment by a religious woman challenges widespread assumptions about its limited availability in medieval Europe and the gendered production of illuminated texts.


Assuntos
Silicatos de Alumínio/história , Cálculos Dentários/história , Literatura Medieval/história , Freiras/história , Datação Radiométrica , Restos Mortais , Cor , Feminino , Alemanha , História Medieval , Humanos , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Pinturas , Espectrometria por Raios X , Análise Espectral Raman
7.
AJNR Am J Neuroradiol ; 39(8): 1390-1399, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29348136

RESUMO

Resting-state fMRI was first described by Biswal et al in 1995 and has since then been widely used in both healthy subjects and patients with various neurologic, neurosurgical, and psychiatric disorders. As opposed to paradigm- or task-based functional MR imaging, resting-state fMRI does not require subjects to perform any specific task. The low-frequency oscillations of the resting-state fMRI signal have been shown to relate to the spontaneous neural activity. There are many ways to analyze resting-state fMRI data. In this review article, we will briefly describe a few of these and highlight the advantages and limitations of each. This description is to facilitate the adoption and use of resting-state fMRI in the clinical setting, helping neuroradiologists become familiar with these techniques and applying them for the care of patients with neurologic and psychiatric diseases.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Imageamento por Ressonância Magnética/métodos , Humanos , Masculino , Descanso
8.
Osteoarthritis Cartilage ; 25(8): 1353-1361, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28365462

RESUMO

OBJECTIVE: Arthroscopy with lavage and synovectomy can remove tissue debris from the joint space and the synovial lining to provide pain relief to patients with osteoarthritis (OA). Here, we developed an in vitro model to study the interaction of cartilage wear particles with fibroblast-like synoviocytes (FLS) to better understand the interplay of cartilage particulates with cytokines on cells of the synovium. METHOD: In this study sub-10 µm cartilage particles or 1 µm latex particles were co-cultured with FLS ±10 ng/mL interleukin-1α (IL-1α) or tumor necrosis factor-α (TNF-α). Samples were analyzed for DNA, glycosaminoglycan (GAG), and collagen, and media samples were analyzed for media GAG, nitric oxide (NO) and prostaglandin-E2 (PGE2). The nature of the physical interaction between the particles and FLS was determined by microscopy. RESULTS: Both latex and cartilage particles could be phagocytosed by FLS. Cartilage particles were internalized and attached to the surface of both dense monolayers and individual cells. Co-culture of FLS with cartilage particulates resulted in a significant increase in cell sheet DNA and collagen content as well as NO and PGE2 synthesis compared to control and latex treated groups. CONCLUSION: The proliferative response of FLS to cartilage wear particles resulted in an overall increase in extracellular matrix (ECM) content, analogous to the thickening of the synovial lining observed in OA patients. Understanding how cartilage particles interface with the synovium may provide insight into how this interaction contributes to OA progression and may guide the role of lavage and synovectomy for degenerative disease.


Assuntos
Cartilagem , Látex , Membrana Sinovial/química , Sinovite/patologia , Animais , Bovinos , Células Cultivadas , Citocinas/farmacologia , Fibroblastos/fisiologia , Modelos Biológicos , Fagocitose/fisiologia
9.
J Clin Pharm Ther ; 41(4): 414-8, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27255463

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Patients admitted to general medical units and emergency short-stay units are often complex with multiple comorbidities, polypharmacy and at risk for drug-related problems associated with increased morbidity and mortality. The aim of this study was to evaluate the effectiveness of a partnered pharmacist charting model completed at the time of admission to prevent medication errors. METHODS: We conducted an unblinded cluster randomized controlled trial comparing partnered pharmacist charting to standard medical charting among patients admitted to general medical units and emergency short-stay units with complex medication regimens or polypharmacy. This trial was conducted at an adult major referral hospital in metropolitan Melbourne, Australia, with an annual emergency department attendance of approximately 60 000 patients. The evaluation included patients' medication charts written in the period of 16 March 2015 to 27 July 2015. Patients randomized to the intervention were managed using the partnered pharmacist charting model. The primary outcome variable was a medication error identified by an independent assessor within 24 h of admission, who was not part of the patient's admission process. RESULTS: Of the 473 patients who received standard medical staff charting during the study period, 372 (78·7%) had at least one medication error identified compared to 15 patients (3·7%) on the partnered pharmacist charting arm (P < 0·001). The relative risk of an error with standard medical charting was 21·4 (95% CI: 13·0-35·0) with a number needed to treat (NNT) to prevent one error of 1·3 (95% CI: 1·3-1·4), and the relative risk of a high or extreme risk error with standard medical charting was 150·9 (95% CI: 21·2-1072·9) with a NNT to prevent one high or extreme error of 2·7 (95% CI 2·4-3·1). WHAT IS NEW AND CONCLUSION: Partnering between medical staff and pharmacists to jointly chart initial medications on admission significantly reduced inpatient medication errors (including errors of high and extreme risk) among general medical and emergency short-stay patients with complex medication regimens or polypharmacy.


Assuntos
Erros de Medicação/prevenção & controle , Admissão do Paciente/normas , Farmacêuticos/organização & administração , Serviço de Farmácia Hospitalar/organização & administração , Idoso , Idoso de 80 Anos ou mais , Austrália , Análise por Conglomerados , Serviço Hospitalar de Emergência/organização & administração , Feminino , Hospitalização , Humanos , Pessoa de Meia-Idade , Polimedicação , Papel Profissional
10.
Ir Med J ; 108(9): 283-4, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26625656

RESUMO

We present a case of a deep full thickness burn from topical formic acid. Our patient developed a burn over her proximal interphalangeal joint (PIPJ) of her finger, secondary to inappropriate application of an anti-wart treatment. The burn required extensive deridement, and the resultant defect was reconstructed using a subcutaneous flap from the adjacent finger (a reverse cross finger flap). She was reviewed six months post-surgery, and overall she has a sub-optimal result. This incident was referred to the Irish Medicine's Board who have since reviewed the case and ordered the manufacturer to alter their usage instructions.


Assuntos
Queimaduras Químicas/etiologia , Fármacos Dermatológicos/efeitos adversos , Traumatismos dos Dedos/etiologia , Formiatos/efeitos adversos , Verrugas/tratamento farmacológico , Administração Cutânea , Adulto , Queimaduras Químicas/cirurgia , Desbridamento , Fármacos Dermatológicos/administração & dosagem , Feminino , Traumatismos dos Dedos/cirurgia , Formiatos/administração & dosagem , Humanos , Medicamentos sem Prescrição/administração & dosagem , Medicamentos sem Prescrição/efeitos adversos , Retalhos Cirúrgicos
11.
J Wound Care ; 23(7): 355-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25041311

RESUMO

OBJECTIVE: Reconstruction of large abdominal wall defects is a challenging procedure, often contraindicated in critically ill patients, with high incidences of complications. We present a case of a patient with a large abdominal wall defect who had reconstruction with MatriDerm® (an engineered dermal template) and split thickness skin grafting (SSG) as an alternative to reconstruction with myo- or fascio-cutaneous flaps. Successful wound closure was achieved with a single technique, while providing a robust reconstruction and an interface between skin and underlying viscera, should further surgery be necessary.


Assuntos
Parede Abdominal/cirurgia , Abdominoplastia/métodos , Colágeno/uso terapêutico , Elastina/uso terapêutico , Fasciite Necrosante/cirurgia , Transplante de Pele/métodos , Desbridamento , Feminino , Humanos , Pessoa de Meia-Idade , Tratamento de Ferimentos com Pressão Negativa , Cicatrização
12.
J Huazhong Univ Sci Technolog Med Sci ; 34(3): 354-358, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24939298

RESUMO

Under global cerebral ischemia, the effect of different brain temperature on cerebral ischemic injury was studied. Male Sprague-Dawley rats were divided into normothermic (37-38°C) ischemia, mild hypothermic (31-32°C) ischemia, hyperthermic (41-42°C) ischemia and sham-operated groups. Global cerebral ischemia was established using the Pulsinelli four-vessel occlusion model and brain temperature was maintained at defined level for 60 min after 20-min ischemia. The expression of c-fos protein and the levels of malondialdehyde (MDA) and lactate in brain regions were detected by immunochemistry and spectrophotometrical methods, respectively. C-fos positive neurons were found in the hippocampus and cerebral cortex after cerebral ischemia reperfusion. Mild hypothermia increased the expression of c-fos protein in both areas, whereas hyperthermia decreased the expression of c-fos protein in the hippocampus at 24 h reperfusion, and the cerebral cortex at 48 h reperfusion when compared to normothermic conditions. In normothermic, mild hypothermic and hyperthermic ischemia groups, the levels of MDA and lactate in brain tissue were increased at 24, 48 and 72 h reperfusion following 20-min ischemia as compared with the sham-operated group (P<0.01). The levels of MDA and lactate in mild hypothermic group were significantly lower than those in normothermic group (P<0.01). It is suggested that brain temperature influences the translation of the immunoreactive protein product of c-fos after global cerebral ischemia, and MDA and lactate are also affected by hypothermia and hyperthermia.


Assuntos
Isquemia Encefálica/metabolismo , Encéfalo/metabolismo , Ácido Láctico/metabolismo , Malondialdeído/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Animais , Temperatura Corporal , Encéfalo/irrigação sanguínea , Encéfalo/fisiopatologia , Isquemia Encefálica/fisiopatologia , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/metabolismo , Córtex Cerebral/fisiopatologia , Hipocampo/irrigação sanguínea , Hipocampo/metabolismo , Hipocampo/fisiopatologia , Imunoquímica , Masculino , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/fisiopatologia , Espectrofotometria , Temperatura , Fatores de Tempo , Proteína Supressora de Tumor p53/metabolismo
15.
AJNR Am J Neuroradiol ; 34(2): 402-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22859283

RESUMO

BACKGROUND AND PURPOSE: Parameters other than luminal narrowing are needed to predict the risk of stroke more reliably, particularly in patients with <70% stenosis. The goal of our study was to identify clinical risk factors and CT features of carotid atherosclerotic plaques, in a retrospective cohort of patients free of stroke at baseline, that are independent predictors of incident stroke on follow-up. MATERIALS AND METHODS: We identified a retrospective cohort of patients admitted to our emergency department with suspected stroke between 2001-2007 who underwent a stroke work-up including a CTA of the carotid arteries that was subsequently negative for acute stroke. All patients also had to receive a follow-up brain study at least 2 weeks later. From a random sample, we reviewed charts and imaging studies of patients with subsequent new stroke on follow-up as well as those who remained stroke-free. All patients were classified either as "new carotid infarct patients" or "no-new carotid infarct patients" based on the Causative Classification for Stroke. Independently, the baseline CTA studies were processed using a custom, CT-based automated computer classifier algorithm that quantitatively assesses a set of carotid CT features (wall thickness, plaque ulcerations, fibrous cap thickness, lipid-rich necrotic core, and calcifications). Univariate and multivariate statistical analyses were used to identify any significant differences in CT features between the patient groups in the sample. Subsequent ROC analysis allowed comparison to the classic NASCET stenosis rule in identifying patients with incident stroke on follow-up. RESULTS: We identified a total of 315 patients without a new carotid stroke between baseline and follow-up, and 14 with a new carotid stroke between baseline and follow-up, creating the main comparison groups for the study. Statistical analysis showed age and use of antihypertensive drugs to be the most significant clinical variables, and maximal carotid wall thickness was the most relevant imaging variable. The use of age ≥ 75 years, antihypertensive medication use, and a maximal carotid wall thickness of at least 4 mm was able to successfully identify 10 of the 14 patients who developed a new incident infarct on follow-up. ROC analysis showed an area under the ROC curve of 0.706 for prediction of new stroke with this new model. CONCLUSIONS: Our new paradigm of using age ≥ 75 years, history of hypertension, and carotid maximal wall thickness of >4 mm identified most of the patients with subsequent new carotid stroke in our study. It is simple and may help clinicians choose the patients at greatest risk of developing a carotid infarct, warranting validation with a prospective observational study.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/epidemiologia , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/epidemiologia , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Artéria Carótida Primitiva/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Hipertensão/epidemiologia , Incidência , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/epidemiologia , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos , Medição de Risco/métodos , Fatores de Risco , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X
17.
Appl Environ Microbiol ; 78(6): 1701-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22247155

RESUMO

Escherichia coli isolates were recovered from the National Antimicrobial Resistance Monitoring System retail meat program and examined for antimicrobial susceptibility. Retail meat samples (n = 11,921) from four U.S. states collected during 2002 to 2008, consisting of 2,988 chicken breast, 2,942 ground turkey, 2,991 ground beef, and 3,000 pork chop samples, were analyzed. A total of 8,286 E. coli isolates were recovered. The greatest numbers of samples contaminated with the organism were chicken (83.5%) and turkey (82.0%), followed by beef (68.9%) and pork (44.0%). Resistance was most common to tetracycline (50.3%), followed by streptomycin (34.6%), sulfamethoxazole-sulfisoxazole (31.6%), ampicillin (22.5%), gentamicin (18.6%), kanamycin (8.4%), amoxicillin-clavulanic acid (6.4%), and cefoxitin (5.2%). Less than 5% of the isolates had resistance to trimethoprim, ceftriaxone, ceftiofur, nalidixic acid, chloramphenicol, and ciprofloxacin. All isolates were susceptible to amikacin. Compared to beef and pork isolates, the poultry meat isolates had a greater percentage of resistance to all tested drugs, with the exception of chloramphenicol, to which pork isolates had the most resistance. More than half of the turkey isolates (56%) were resistant to multidrugs (≥3 classes) compared to 38.9% of chicken, 17.3% of pork, and 9.3% of beef isolates. The bla(CMY) gene was present in all ceftriaxone- and ceftiofur-resistant isolates. The cmlA, flo, and catI genes were present in 45%, 43%, and 40% of chloramphenicol-resistant isolates, respectively. Most nalidixic acid-resistant isolates (98.5%) had a gyrA mutation in S83 or D87 or both, whereas only 6.7% had a parC mutation in either S80 or E84. The results showed that E. coli was commonly present in the retail meats, and antimicrobial resistance profiles differed according to the animal origin of the isolates.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Carne/microbiologia , Animais , Proteínas de Escherichia coli/genética , Genes Bacterianos , Testes de Sensibilidade Microbiana , Prevalência , Estados Unidos
18.
Chin Med J (Engl) ; 124(17): 2764-6, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22040438

RESUMO

BACKGROUND: The optimal time window for the administration of hypothermia following cerebral ischemia has been studied for decades, with disparity outcomes. In this study, the efficacy of mild brain hypothermia beginning at different time intervals on brain endogenous antioxidant enzyme and energy metabolites was investigated in a model of global cerebral ischemia. METHODS: Forty-eight male Sprague-Dawley rats were divided into a sham-operated group, a normothermia (37°C - 38°C) ischemic group and a mild hypothermic (31°C - 32°C) ischemia groups. Rats in the last group were subdivided into four groups: 240 minutes of hypothermia, 30 minutes of normothermia plus 210 minutes of hypothermia, 60 minutes of normothermia plus 180 minutes of hypothermia and 90 minutes of normothermia plus 150 minutes of hypothermia (n = 8). Global cerebral ischemia was established using the Pulsinelli four-vessel occlusion model for 20 minutes and mild hypothermia was applied after 20 minutes of ischemia. Brain tissue was collected following 20 minutes of cerebral ischemia and 240 minutes of reperfusion, and used to measure the levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), reduced glutathione (GSH) and adenosine triphosphate (ATP). RESULTS: Mild hypothermia that was started within 0 to 60 minutes delayed the consumption of SOD, GSH-Px, GSH, and ATP (P < 0.05 or P < 0.01) in ischemic tissue, as compared to a normothermic ischemia group. In contrast, mild hypothermia beginning at 90 minutes had little effect on the levels of SOD, GSH-Px, GSH, and ATP (P > 0.05). CONCLUSIONS: Postischemic mild brain hypothermia can significantly delay the consumption of endogenous antioxidant enzymes and energy metabolites, which are critical to the process of cerebral protection by mild hypothermia. These results show that mild hypothermia limits ischemic injury if started within 60 minutes, but loses its protective effects when delayed until 90 minutes following cerebral ischemia.


Assuntos
Antioxidantes/metabolismo , Isquemia Encefálica/enzimologia , Hipotermia Induzida , Trifosfato de Adenosina/metabolismo , Animais , Isquemia Encefálica/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Temperatura
19.
Appl Environ Microbiol ; 76(24): 7949-56, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20971875

RESUMO

The emergence of antimicrobial resistance in Campylobacter spp. has been a growing public health concern globally. The objectives of this study were to determine the prevalence, antimicrobial susceptibility, and genetic relatedness of Campylobacter spp. recovered by the National Antimicrobial Resistance Monitoring System (NARMS) retail meat program. Retail meat samples (n = 24,566) from 10 U.S. states collected between 2002 and 2007, consisting of 6,138 chicken breast, 6,109 ground turkey, 6,171 ground beef, and 6,148 pork chop samples, were analyzed. A total of 2,258 Campylobacter jejuni, 925 Campylobacter coli, and 7 Campylobacter lari isolates were identified. Chicken breast samples showed the highest contamination rate (49.9%), followed by ground turkey (1.6%), whereas both pork chops and ground beef had <0.5% contamination. The most common resistance was to doxycycline/tetracycline (46.6%), followed by nalidixic acid (18.5%), ciprofloxacin (17.4%), azithromycin and erythromycin (2.8%), telithromycin (2.4%), clindamycin (2.2%), and gentamicin (<0.1%). In a subset of isolates tested, no resistance to meropenem and florfenicol was seen. C. coli isolates showed higher resistance rates to antimicrobials, with the exception of doxycycline/tetracycline, than those seen for C. jejuni. Pulsed-field gel electrophoresis (PFGE) fingerprinting resulted in 1,226 PFGE profiles among the 2,318 isolates, with many clones being widely dispersed throughout the 6-year sampling period.


Assuntos
Antibacterianos/farmacologia , Campylobacter coli/efeitos dos fármacos , Campylobacter jejuni/efeitos dos fármacos , Campylobacter lari/efeitos dos fármacos , Farmacorresistência Bacteriana , Carne/microbiologia , Animais , Campylobacter coli/isolamento & purificação , Campylobacter jejuni/isolamento & purificação , Campylobacter lari/isolamento & purificação , Bovinos , Galinhas , Análise por Conglomerados , Impressões Digitais de DNA , Eletroforese em Gel de Campo Pulsado , Genótipo , Tipagem Molecular , Suínos , Perus , Estados Unidos
20.
Nicotine Tob Res ; 12(6): 613-21, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20488931

RESUMO

INTRODUCTION: Vietnamese American men have smoking prevalence rates higher than the general population. We analyzed Vietnamese American smoking behavior by demographic and health-related factors, including some specific to Vietnamese, in the largest tobacco-specific survey yet targeting the Vietnamese population. METHODS: Using a statewide surname probability sample and computer-assisted telephone interviewing, we surveyed 1,101 Vietnamese men and 1,078 Vietnamese women in California (63.5% participation among successfully contacted eligible individuals) in 2007-2008. We conducted multivariate regression models to analyze the association between Vietnamese male smoking status and demographic and health-related factors. RESULTS: Among women, <1% were current smokers and <2% were former smokers. Among men, 25% were current and 24% were former smokers. Regression models for Vietnamese men delineated factors associated with both current and former smoking (vs. never smoking): being married, being employed, having lower educational attainment, and consuming alcohol. Other factors associated with current smoking (vs. never smoking) were having no health insurance, having seen a Vietnamese doctor or no doctor visit in the past year, having Vietnamese military or Vietnamese reeducation camp experience, having less knowledge about the harms of smoking, and reporting higher depression symptoms. Increasing age and not being Buddhist were associated with former (vs. never) smoking. DISCUSSION: Smoking patterns of Vietnamese women and Vietnamese men are significantly different from the general California population. Tobacco control efforts targeting Vietnamese men should include community outreach since current smokers have low health care access, utilization, and knowledge.


Assuntos
Fumar/etnologia , Fumar/epidemiologia , Adolescente , Adulto , Idoso , California/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Análise de Regressão , Fumar/psicologia , Vietnã/etnologia , Adulto Jovem
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