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1.
BMC Med Educ ; 23(1): 457, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37340427

RESUMO

OBJECTIVES: A partnership model in interprofessional education (IPE) is important in promoting a sense of global citizenship while preparing students for cross-sector problem-solving. However, the literature remains scant in providing useful guidance for the development of an IPE programme co-implemented by external partners. In this pioneering study, we describe the processes of forging global partnerships in co-implementing IPE and evaluate the programme in light of the preliminary data available. METHODS: This study is generally quantitative. We collected data from a total of 747 health and social care students from four higher education institutions. We utilized a descriptive narrative format and a quantitative design to present our experiences of running IPE with external partners and performed independent t-tests and analysis of variance to examine pretest and posttest mean differences in students' data. RESULTS: We identified factors in establishing a cross-institutional IPE programme. These factors include complementarity of expertise, mutual benefits, internet connectivity, interactivity of design, and time difference. We found significant pretest-posttest differences in students' readiness for interprofessional learning (teamwork and collaboration, positive professional identity, roles, and responsibilities). We also found a significant decrease in students' social interaction anxiety after the IPE simulation. CONCLUSIONS: The narrative of our experiences described in this manuscript could be considered by higher education institutions seeking to forge meaningful external partnerships in their effort to establish interprofessional global health education.


Assuntos
Educação Interprofissional , Estudantes de Ciências da Saúde , Humanos , Aprendizagem , Resolução de Problemas , Universidades , Relações Interprofissionais , Atitude do Pessoal de Saúde
2.
Clin Radiol ; 77(8): 592-599, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35599188

RESUMO

Nasopharyngeal carcinoma is frequently an undifferentiated squamous cell carcinoma, which is primarily treated with radiotherapy with or without chemotherapy; however, for residual or recurrent cancer, salvage surgery is the treatment of choice for resectable disease because it reduces the significant morbidity associated with re-irradiation. This review highlights the current surgical approach, mapping the extent of disease with an emphasis on magnetic resonance imaging (MRI) and integrated positron-emission tomography (PET)/computed tomography (CT), imaging features that determine operability for nasopharyngectomy and neck dissection, and need for a succinct radiological report and multidisciplinary team discussion, which are of paramount importance for successful surgical planning.


Assuntos
Neoplasias Nasofaríngeas , Cirurgiões , Humanos , Carcinoma Nasofaríngeo/diagnóstico por imagem , Carcinoma Nasofaríngeo/cirurgia , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/cirurgia , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/cirurgia , Terapia de Salvação , Tomografia Computadorizada por Raios X/métodos
3.
Malays J Pathol ; 43(1): 81-85, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33903310

RESUMO

BACKGROUND: Small bowel volvulus is defined as the torsion of the small intestine, potentially leading to bowel obstruction, gangrene and perforation. It is a rare condition, especially in adults. CASE PRESENTATION: A 30-year-old man was retrieved from the jungle with severe weight loss and abdominal symptoms. He succumbed to death despite 22 days of intensive medical treatment. An autopsy revealed a ruptured gangrenous ileal volvulus with peritonitis and subdiaphragmatic abscess. Further laboratory analysis detected systemic Candida tropicalis and intestinal gramnegative bacterial sepsis, systemic Zika virus viremia, leptospirosis complicating rhabdomyolysis and disseminated intravascular coagulopathy, Type I Herpes Simplex virus infection of the tongue and upper gastrointestinal tract. The cause of death was the ruptured ileal volvulus, complicated with upper gastrointestinal bleeding due to Herpes simplex virus esophagitis in a malnourished patient with resolving leptospirosis and underlying Zika virus co-infection. CONCLUSION: Rare clinical scenarios of adult-onset intestinal volvulus with concomitant multiple infections precludes clinical diagnosis and early treatment, leading to devastating consequences of clinical outcome. The positive clinical and postmortem correlation is a good learning lesson in many disciplines of medicine and science.


Assuntos
Obstrução Intestinal , Volvo Intestinal , Leptospirose , Infecção por Zika virus , Zika virus , Adulto , Autopsia , Humanos , Volvo Intestinal/complicações , Masculino
4.
Clin Infect Dis ; 57(8): 1069-77, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23876395

RESUMO

BACKGROUND: Better understanding of complications and outcomes of adults hospitalized with respiratory syncytial virus (RSV) infection is necessary. METHODS: A retrospective cohort study was conducted on all adults (≥ 18 years) admitted to 3 acute care general hospitals in Hong Kong with virologically confirmed RSV infection during 2009-2011 (N = 607). Adults hospitalized for seasonal influenza during the period were used for comparison (n = 547). Both infections were prospectively diagnosed following a standard protocol. Independent reviews of chest radiographs were performed by radiologists. Main outcome measures were all-cause death, respiratory failure requiring ventilatory support, and hospitalization duration. Cox proportional hazards models were used for analyses. RESULTS: The mean age of RSV patients was 75 (SD, 16) years; 87% had underlying conditions. Lower respiratory and cardiovascular complications were diagnosed in 71.9% (pneumonia, 42.3%; acute bronchitis, 21.9%; chronic obstructive pulmonary disease/asthma exacerbation, 27.3%) and 14.3% of patients, respectively; 12.5% had bacterial superinfections. Supplemental oxygen and ventilatory support were required in 67.9% and 11.1%, respectively. Crude all-cause mortality was 9.1% and 11.9% within 30 days and 60 days, respectively; mean length of stay of survivors was 12 (SD, 13) days. Advanced age, radiographic pneumonia, requirement for ventilation, bacterial superinfection, and elevated urea level and white blood cell count were independently associated with poorer survival. Systemic corticosteroid use was associated with longer hospitalization and secondary infections. The overall outcomes of survival and length of stay were not significantly different from those in influenza. CONCLUSIONS: RSV can cause severe lower respiratory complications in older adults, resulting in respiratory failure, prolonged hospitalization, and high mortality similar to seasonal influenza. Corticosteroids did not seem to improve outcomes. The unmet need for antiviral therapy and vaccination against RSV in adults should be promptly addressed.


Assuntos
Infecções por Vírus Respiratório Sincicial/mortalidade , Infecções Respiratórias/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade , Estudos Retrospectivos
5.
Curr Top Microbiol Immunol ; 359: 95-104, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22427144

RESUMO

The clinicopathological features of human Nipah virus and Hendra virus infections appear to be similar. The clinical manifestations may be mild, but if severe, includes acute encephalitic and pulmonary syndromes with a high mortality. The pathological features in human acute henipavirus infections comprise vasculopathy (vasculitis, endothelial multinucleated syncytia, thrombosis), microinfarcts and parenchymal cell infection in the central nervous system, lung, kidney and other major organs. Viral inclusions, antigens, nucleocapsids and RNA are readily demonstrated in blood vessel wall and numerous types of parenchymal cells. Relapsing henipavirus encephalitis is a rare complication reported in less than 10% of survivors of the acute infection and appears to be distinct from the acute encephalitic syndrome. Pathological evidence suggests viral recrudescence confined to the central nervous system as the cause.


Assuntos
Vasos Sanguíneos/patologia , Sistema Nervoso Central/patologia , Encefalite Viral/patologia , Infecções por Henipavirus/patologia , Infarto do Miocárdio/patologia , Miocárdio/patologia , Animais , Vasos Sanguíneos/virologia , Sistema Nervoso Central/virologia , Encefalite Viral/complicações , Encefalite Viral/mortalidade , Encefalite Viral/virologia , Vírus Hendra/patogenicidade , Vírus Hendra/fisiologia , Infecções por Henipavirus/complicações , Infecções por Henipavirus/mortalidade , Infecções por Henipavirus/virologia , Humanos , Rim/patologia , Rim/virologia , Pulmão/patologia , Pulmão/virologia , Infarto do Miocárdio/complicações , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/virologia , Vírus Nipah/patogenicidade , Vírus Nipah/fisiologia , Taxa de Sobrevida
6.
J Nanosci Nanotechnol ; 13(7): 5158-63, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23901546

RESUMO

Molecules with donor (diphenylamine) and acceptor moieties (dicyano or cyanoacrylic acid moieties) were linked by fluorene or spirobisfluorene cores and the chain length has been changed by introducing a thiophene group between fluorene and diphenylamine. Four different kinds of fluorene and spirobisfluorene compounds were adsorbed from highly diluted solutions at ultra-thin nanoporous TiO2 (np-TiO2), Au and ITO surfaces. Charge separation has been investigated by surface photovoltage spectroscopy in the fixed capacitor and Kelvin probe arrangements in vacuum. Striking differences between the interaction of linking (dicyano or cyanoacrylic moieties) and different substrates were observed. Intra-molecular charge separation and electron injection have been distinguished and the directed adsorption of spiro compounds was deduced.


Assuntos
Nanopartículas Metálicas/química , Nanopartículas Metálicas/efeitos da radiação , Campos Eletromagnéticos , Transporte de Elétrons , Luz , Teste de Materiais , Nanopartículas Metálicas/ultraestrutura , Óxidos/química , Óxidos/efeitos da radiação , Propriedades de Superfície/efeitos da radiação
8.
J Urol ; 188(3): 837-42, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22819406

RESUMO

PURPOSE: We assessed the effects of different shock wave delivery rates in patients treated with shock wave lithotripsy for renal stones, particularly treatment success, degree of renal injury and pain experienced, and analgesic demand. MATERIALS AND METHODS: A total of 206 patients with renal stones were prospectively randomized to receive shock waves delivered at 60 (group 1) or 120 (group 2) shocks per minute using a Sonolith® Vision at a single institution in October 2008 and August 2010. The primary outcome was successful treatment 12 weeks after 1 lithotripsy session. Secondary outcome measures included the degree of renal injury, as reflected by changes in urinary markers of renal injury, as well as patient pain scores and analgesia consumed during treatment. RESULTS: Mean stone size in groups 1 and 2 was 8.95 and 9.28 mm, respectively (p = 0.525). The overall treatment success rate was 43.2%. It was significantly better in group 1 than in group 2 (50.5% vs 35.9%, p = 0.035). There was no between group difference in the success rate for stones 10 mm or less but the success rate was statistically better for group 1 patients with stones greater than 10 mm (p = 0.002). Immediately after shock wave lithotripsy there was a statistically significant greater increase in urinary NAG (p = 0.003) and interleukin-18 (p = 0.022) in group 1. There was no between group difference in pain scores, analgesic consumption during shock wave lithotripsy or unplanned hospital visits. CONCLUSIONS: Slower shock wave delivery yielded better treatment outcomes, particularly for stones greater than 10 mm, without increasing patient pain or analgesic demand. However, slower shock wave delivery also appeared to cause a statistically significant increase in acute renal injury markers, although the clinical implication was uncertain.


Assuntos
Cálculos Renais/terapia , Litotripsia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Rim/lesões , Litotripsia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Estudos Prospectivos , Método Simples-Cego
9.
Neuropathol Appl Neurobiol ; 38(5): 443-53, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22236252

RESUMO

AIMS: To investigate if two important epidemic viral encephalitis in children, Enterovirus 71 (EV71) encephalomyelitis and Japanese encephalitis (JE) whose clinical and pathological features may be nonspecific and overlapping, could be distinguished. METHODS: Tissue sections from the central nervous system of infected cases were examined by light microscopy, immunohistochemistry and in situ hybridization. RESULTS: All 13 cases of EV71 encephalomyelitis collected from Asia and France invariably showed stereotyped distribution of inflammation in the spinal cord, brainstem, hypothalamus, cerebellar dentate nucleus and, to a lesser extent, cerebral cortex and meninges. Anterior pons, corpus striatum, thalamus, temporal lobe, hippocampus and cerebellar cortex were always uninflamed. In contrast, the eight JE cases studied showed inflammation involving most neuronal areas of the central nervous system, including the areas that were uninflamed in EV71 encephalomyelitis. Lesions in both infections were nonspecific, consisting of perivascular and parenchymal infiltration by inflammatory cells, oedematous/necrolytic areas, microglial nodules and neuronophagia. Viral inclusions were absent. CONCLUSIONS: Immunohistochemistry and in situ hybridization assays were useful to identify the causative virus, localizing viral antigens and RNA, respectively, almost exclusively to neurones. The stereotyped distribution of inflammatory lesions in EV71 encephalomyelitis appears to be very useful to help distinguish it from JE.


Assuntos
Antígenos Virais/análise , Sistema Nervoso Central/patologia , Encefalite Japonesa/patologia , Enterovirus Humano A , Infecções por Enterovirus/patologia , RNA Viral/análise , Adolescente , Ásia , Sistema Nervoso Central/virologia , Criança , Pré-Escolar , Encefalite Japonesa/virologia , Enterovirus Humano A/genética , Enterovirus Humano A/isolamento & purificação , Enterovirus Humano A/metabolismo , Infecções por Enterovirus/virologia , Feminino , França , Humanos , Imuno-Histoquímica , Masculino , Adulto Jovem
10.
Eur Radiol ; 22(4): 832-6, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22080282

RESUMO

UNLABELLED: The management of a neck mass is dictated by its nature, location and extent. Pathological diagnosis by fine needle aspiration cytology (FNAC) or core biopsy is often required before proceeding to definitive treatment. It is not uncommon for the cytology result to come back as inadequate for various reasons. The unique design of the end-cutting biopsy needle in our experience makes it a good choice for use in obtaining both transcutaneous and intraoral biopsy under ultrasound guidance of neck lesions and serves as a useful alternative or adjunct to FNAC. Although there is, as yet, only a limited evidence base about end-cutting in comparison to side-cutting needles, they carry several potential advantages. KEY POINTS: End-cutting needles are safe to use for lesions close to vital structures. End-cutting needles yield sufficient tissue samples in a single pass. End-cutting biopsy needles are a useful adjunct to FNAC.


Assuntos
Biópsia por Agulha/instrumentação , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/patologia , Pescoço/diagnóstico por imagem , Pescoço/patologia , Cirurgia Assistida por Computador/instrumentação , Ultrassonografia de Intervenção/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos
11.
Hong Kong Med J ; 18(3): 207-13, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22665684

RESUMO

OBJECTIVE: To compare the outcome of cryothermal and radiofrequency energy transcatheter ablation of atrioventricular junctional re-entrant tachycardia in children and adolescents. DESIGN: Case series with internal comparison. SETTING: Two hospitals in Hong Kong. PATIENTS: Consecutive transcatheter ablation procedures for atrioventricular junctional re-entrant tachycardia in children and adolescents in our unit from August 2000 to September 2008 were retrospectively reviewed. Radiofrequency ablation was performed from August 2000 to June 2005, and cryoablation from July 2005 to September 2008. MAIN OUTCOME MEASURES: Demographic data, outcome and procedural details. RESULTS: Thirty-eight procedures were reviewed. The radiofrequency ablation group (n=20) and cryoablation group (n=18) had similar demographic characteristics, except that there were more patients with congenital heart disease in the latter group (P=0.03). Acute procedural success rate was 100% in both groups. One patient from the radiofrequency ablation group had recurrence of atrioventricular junctional re-entrant tachycardia. The frequency of post-ablation persistent heart block was higher in the radiofrequency ablation than cryoablation group (10% vs 0%, P=0.17), but this difference was not statistically significant. A shorter fluoroscopy time was noted in the cryoablation group (31 ± 13 vs 38 ± 18 minutes; P=0.03). CONCLUSIONS: Transcatheter cryoablation for atrioventricular junctional re-entrant tachycardia in children and adolescents is as effective as radiofrequency ablation over the medium term. It has an excellent safety profile in terms of avoiding heart block.


Assuntos
Arritmias Cardíacas/cirurgia , Ablação por Cateter/métodos , Criocirurgia/métodos , Taquicardia por Reentrada no Nó Atrioventricular/cirurgia , Adolescente , Ablação por Cateter/efeitos adversos , Criança , Criocirurgia/efeitos adversos , Feminino , Seguimentos , Hong Kong , Humanos , Masculino , Estudos Retrospectivos , Resultado do Tratamento
13.
Clin Radiol ; 66(9): 799-807, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21530955

RESUMO

OBJECTIVE: To evaluate real-time qualitative ultrasound elastography for focal thyroid masses undergoing fine-needle aspiration in a routine thyroid ultrasound clinic. MATERIALS AND METHODS: Ninety-four thyroid nodules scheduled for fine-needle aspiration cytology in a thyroid ultrasound clinic also underwent real-time freehand elastography. Colour-scaled elastograms were graded visually on the stiffness of the solid component of nodules relative to thyroid parenchyma using an elastography score (ES) scale from 1 (soft) to 4 (stiff). The ES for benign and malignant nodules and the influence of cystic change on ES were analysed using Chi-square with trend and Fishers exact tests, with a p<0.05 used to indicate statistical significance. RESULTS: There were 19 papillary carcinomas, five metastases, 57 hyperplastic nodules, and four follicular adenomas based on definitive cytology (n=54) or histology (n=31). Nine nodules were excluded due to indeterminate cytology and no histology. Of malignancies (all solid), two were ES=1, four were ES=2, eight were ES=3, and 10 were ES=4. Of benign nodules, 17 were ES=1, 17 were ES=2, 16 were ES=3, and 11 were ES=4. An ES>2 was more common in benign nodules with predominant cystic components (17/18) than mildly cystic (3/12) or completely solid (7/31) benign nodules (p=0.0004, p<0.0001). The ES was not significantly different between benign and malignant nodules (p=0.09) unless partially cystic nodules were excluded (p=0.005). For solid nodules, an ES>2 optimally predicted malignancy, achieving 74% sensitivity, 77% specificity, and 76% accuracy. CONCLUSION: Qualitative real-time thyroid elastography predicts malignancy only if predominantly cystic nodules are excluded, which may limit its utility in routine clinical practice.


Assuntos
Adenoma/diagnóstico por imagem , Carcinoma Papilar/diagnóstico por imagem , Cistos/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/métodos , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/diagnóstico por imagem , Adenoma/patologia , Idoso , Biópsia por Agulha Fina , Carcinoma Papilar/patologia , Estudos de Coortes , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Neoplasias da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/patologia
14.
Trop Biomed ; 38(3): 239-247, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34362866

RESUMO

Hand, foot and mouth disease (HFMD) is a highly contagious viral disease that predominantly affects children younger than 5 years old. HFMD is primarily caused by enterovirus A71 (EVA71) and coxsackievirus A16 (CV-A16). However, coxsackievirus A10 (CV-A10) and coxsackievirus A6 (CV-A6) are being increasingly reported as the predominant causative of HFMD outbreaks worldwide since the past decade. To date, there are still no licensed multivalent vaccines or antiviral drugs targeting enteroviruses that cause HFMD, despite HFMD outbreaks are still being frequently reported, especially in Asia-Pacific countries. The high rate of transmission, morbidity and potential neurological complications of HFMD is indeed making the development of broad-spectrum antiviral drugs/agents against these enteroviruses a compelling need. In this study, we have investigated the in vitro antiviral effect of 4 Ganoderma neo-japonicum Imazeki (GNJI) crude extracts (S1-S4) against EV-A71, CV-A16, CV-A10 and CV-A6. GNJI is a medicinal mushroom that can be found growing saprophytically on decaying bamboo clumps in Malaysian forests. The antiviral effects of this medicinal mushroom were determined using cytopathic inhibition and virus titration assays. The S2 (1.25 mg/ml) hot aqueous extract demonstrated the highest broad-spectrum antiviral activity against all tested enteroviruses in human primary oral fibroblast cells. Replication of EV-A71, CV-A16 and CVA10 were effectively inhibited at 2 hours post-infection (hpi) to 72 hpi, except for CV-A6 which was only at 2 hpi. S2 also has virucidal activity against EV-A71. Polysaccharides isolated and purified from crude hot aqueous extract demonstrated similar antiviral activity as S2, suggesting that polysaccharides could be one of the active compounds responsible for the antiviral activity shown by S2. To our knowledge, this study demonstrates for the first time the ability of GNJI to inhibit enterovirus infection and replication. Thus, GNJI is potential to be further developed as an antiviral agent against enteroviruses that caused HFMD.


Assuntos
Antivirais , Produtos Biológicos/farmacologia , Enterovirus Humano A , Ganoderma , Antivirais/farmacologia , Células Cultivadas , China , Enterovirus Humano A/efeitos dos fármacos , Infecções por Enterovirus , Fibroblastos/virologia , Ganoderma/química , Doença de Mão, Pé e Boca , Humanos
15.
Neuroepidemiology ; 34(1): 50-4, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19940513

RESUMO

BACKGROUND: The purpose of this prospective study was to examine whether fibrinogen level is associated with Parkinson disease (PD) for both prevalent and incident cases. METHODS: The Honolulu Asia-Aging Study is a longitudinal study of Japanese-American men based on the Honolulu Heart Study birth cohort. The original cohort consisted of 8,006 participants with selective service records who were living on the island of Oahu, Hawaii, in 1965. For this analysis, baseline was defined as the 1991-1993 examination (n = 3,845) when men were aged 71-93 years old. Multivariate logistic regression and Cox proportional hazards models were used, adjusting for potential confounders. RESULTS: We identified 61 prevalent cases and 61 incident cases of PD during the follow-up. High fibrinogen level (presence in the top quintile) was associated with higher frequency of PD for both prevalent (OR = 2.07, 95% CI = 1.10-3.88, p = 0.024) and incident cases (HR = 3.05, 95% CI = 1.34-6.97, p = 0.008) among men aged 76-93 years, after adjusting for age, smoking, and low-density lipoprotein cholesterol. CONCLUSIONS: These results suggest high fibrinogen level is associated with increased risk of PD among men over 75 years.


Assuntos
Asiático , Fibrinogênio/metabolismo , Doença de Parkinson/epidemiologia , Doença de Parkinson/metabolismo , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Seguimentos , Havaí/epidemiologia , Humanos , Incidência , Japão/etnologia , Modelos Logísticos , Masculino , Análise Multivariada , Razão de Chances , Prevalência , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco
16.
J Comp Pathol ; 176: 19-32, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32359633

RESUMO

Coxsackievirus A16 (CV-A16) and enterovirus A71 (EV-A71) are the major causes of hand, foot and mouth disease in young children. Although less so with CV-A16, both viruses are associated with serious neurological syndromes, but the differences between their central nervous system infections remain unclear. We conducted a comparative infection study using clinically-isolated CV-A16 and EV-A71 strains in a 1-day-old mouse model to better understand the neuropathology and neurovirulence of the viruses. New serotype-specific probes for in situ hybridization were developed and validated to detect CV-A16 and EV-A71 RNA in infected tissues. Demonstration of CV-A16 virus antigens/RNA, mainly in the brainstem and spinal cord neurons, confirmed neurovirulence, but showed lower densities than in EV-A71 infected animals. A higher lethal dose50 for CV-A16 suggested that CV-A16 is less neurovirulent. Focal virus antigens/RNA in the anterior horn white matter and adjacent efferent motor nerves suggested that neuroinvasion is possibly via retrograde axonal transport in peripheral motor nerves.


Assuntos
Infecções do Sistema Nervoso Central/virologia , Infecções por Coxsackievirus/virologia , Enterovirus Humano A/patogenicidade , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Camundongos , Virulência
17.
Science ; 369(6510): 1497-1500, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32943524

RESUMO

Binary interactions dominate the evolution of massive stars, but their role is less clear for low- and intermediate-mass stars. The evolution of a spherical wind from an asymptotic giant branch (AGB) star into a nonspherical planetary nebula (PN) could be due to binary interactions. We observed a sample of AGB stars with the Atacama Large Millimeter/submillimeter Array (ALMA) and found that their winds exhibit distinct nonspherical geometries with morphological similarities to planetary nebulae (PNe). We infer that the same physics shapes both AGB winds and PNe; additionally, the morphology and AGB mass-loss rate are correlated. These characteristics can be explained by binary interaction. We propose an evolutionary scenario for AGB morphologies that is consistent with observed phenomena in AGB stars and PNe.

18.
Neuropathol Appl Neurobiol ; 35(3): 296-305, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19473296

RESUMO

AIM: To study the pathology of two cases of human Hendra virus infection, one with no clinical encephalitis and one with relapsing encephalitis. METHODS: Autopsy tissues were investigated by light microscopy, immunohistochemistry and in situ hybridization. RESULTS: In the patient with acute pulmonary syndrome but not clinical acute encephalitis, vasculitis was found in the brain, lung, heart and kidney. Occasionally, viral antigens were demonstrated in vascular walls but multinucleated endothelial syncytia were absent. In the lung, there was severe inflammation, necrosis and viral antigens in type II pneumocytes and macrophages. The rare kidney glomerulus showed inflammation and viral antigens in capillary walls and podocytes. Discrete necrotic/vacuolar plaques in the brain parenchyma were associated with antigens and viral RNA. Brain inflammation was mild although CD68(+) microglia/macrophages were significantly increased. Cytoplasmic viral inclusions and antigens and viral RNA in neurones and ependyma suggested viral replication. In the case of relapsing encephalitis, there was severe widespread meningoencephalitis characterized by neuronal loss, macrophages and other inflammatory cells, reactive blood vessels and perivascular cuffing. Antigens and viral RNA were mainly found in neurones. Vasculitis was absent in all the tissues examined. CONCLUSIONS: The case of acute Hendra virus infection demonstrated evidence of systemic infection and acute encephalitis. The case of relapsing Hendra virus encephalitis showed no signs of extraneural infection but in the brain, extensive inflammation and infected neurones were observed. Hendra virus can cause acute and relapsing encephalitis and the findings suggest that the pathology and pathogenesis are similar to Nipah virus infection.


Assuntos
Encéfalo/patologia , Encefalite Viral/patologia , Vírus Hendra , Infecções por Henipavirus/patologia , Adulto , Antígenos Virais/análise , Encéfalo/irrigação sanguínea , Encéfalo/imunologia , Encéfalo/virologia , Vasos Coronários/patologia , Encefalite Viral/imunologia , Encefalite Viral/virologia , Epêndima/patologia , Epêndima/virologia , Feminino , Vírus Hendra/isolamento & purificação , Infecções por Henipavirus/imunologia , Infecções por Henipavirus/virologia , Humanos , Rim/irrigação sanguínea , Rim/patologia , Rim/virologia , Pulmão/irrigação sanguínea , Pulmão/patologia , Pulmão/virologia , Macrófagos , Masculino , Microglia , Pessoa de Meia-Idade , Miocárdio/patologia , Neurônios/patologia , Neurônios/virologia , RNA Viral/metabolismo , Recidiva , Vasculite/imunologia , Vasculite/patologia , Vasculite/virologia
19.
J Phys Chem B ; 113(25): 8527-31, 2009 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-19485362

RESUMO

By means of time-resolved photoluminescence and photothermal techniques, after-effects from excited-state dynamics, energy migration, and conformational rearrangement of poly(9,9-di-n-octyl-2,7-fluorene) (PFO) and its homologues has been examined and interpreted with rotational potential maps from quantum mechanical calculations. Steady-state photoluminescence spectral changes and time-resolved photoluminescence measurements of oligofluorenes and PFO diluted in toluene suggest excited state ring torsion occurring within 30 ps of photoexitation. With all effects from internal conversion/intersystem crossing processes properly accounted for, we show that the conformational changes associated with this twisting motion can be quantitatively probed by means of photothermal methods. Results suggest mean torsion between neighboring fluorene units by ca. 40 degrees upon excitation, in agreement with the shift of rotational potential minimum from +/-40 degrees (and +/-140 degrees) in the ground state to +/-20 degrees (and +/-160 degrees) in the first excited singlet state according to results of quantum mechanical calculations.


Assuntos
Fluorenos/química , Absorção , Luminescência , Conformação Molecular , Fótons , Rotação , Espectrometria de Fluorescência , Temperatura
20.
Hong Kong Med J ; 15(5): 388-90, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19801699

RESUMO

Popliteal artery entrapment syndrome is an important, albeit infrequent, cause of severe disability among young adults and athletes with anomalous anatomic relationships of the musculotendinous structures surrounding the popliteal artery. We report a case where duplex ultrasonography and dynamic magnetic resonance arteriography was used to diagnose popliteal artery entrapment. We used a posterior surgical approach to give the best view of the anatomic structures compressing the popliteal artery. Compression had not yet damaged the arterial wall, therefore operative decompression of the artery by resection of the aberrant muscle was sufficient. The result was complete recovery, with absence of symptoms and with patency verified by Doppler examination. We conclude that emergency physicians who encounter young patients with progressive lower limb arterial insufficiency should be aware of the possibility of popliteal artery entrapment. Early diagnosis using physical examination, history taking, and imaging is necessary. The treatment of choice is surgical correction to achieve normal anatomy within the popliteal fossa.


Assuntos
Arteriopatias Oclusivas/diagnóstico , Claudicação Intermitente/diagnóstico , Artéria Poplítea/patologia , Adulto , Arteriopatias Oclusivas/cirurgia , Constrição Patológica/diagnóstico , Constrição Patológica/cirurgia , Humanos , Claudicação Intermitente/etiologia , Claudicação Intermitente/cirurgia , Angiografia por Ressonância Magnética/métodos , Masculino , Artéria Poplítea/diagnóstico por imagem , Síndrome , Ultrassonografia Doppler/métodos , Procedimentos Cirúrgicos Vasculares/métodos
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