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1.
Hong Kong Med J ; 29(6): 514-523, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37968897

RESUMO

INTRODUCTION: The utilisation of extracorporeal membrane oxygenation (ECMO) has been rapidly increasing in Hong Kong. This study examined 10-year trends in the utilisation and clinical outcomes of ECMO in Hong Kong. METHODS: We retrospectively reviewed the records of all adult patients receiving ECMO who were admitted to the intensive care units (ICUs) of public hospitals in Hong Kong between 2010 and 2019. Temporal trends across years were assessed using the Mann-Kendall test. Observed hospital mortality was compared with the Acute Physiology and Chronic Health Evaluation (APACHE) IV-predicted mortality. RESULTS: The annual number of patients receiving ECMO increased from 18 to 171 over 10 years. In total, 911 patients received ECMO during the study period: 297 (32.6%) received veno-arterial ECMO, 450 (49.4%) received veno-venous ECMO, and 164 (18.0%) received extracorporeal cardiopulmonary resuscitation. The annual number of patients aged ≥65 years increased from 0 to 47 (27.5%) [P for trend=0.001]. The median (interquartile range) Charlson Comorbidity Index increased from 1 (0-1) to 2 (1-3) [P for trend<0.001] while the median (interquartile range) APACHE IV score increased from 90 (57-112) to 105 (77-137) [P for trend=0.003]. The overall standardised mortality ratio comparing hospital mortality with APACHE IV-predicted mortality was 1.11 (95% confidence interval=1.01-1.22). Hospital and ICU length of stay both significantly decreased (P for trend=0.011 and <0.001, respectively). CONCLUSION: As ECMO utilisation increased in Hong Kong, patients put on ECMO were older, more critically ill, and had more co-morbidities. It is important to combine service expansion with adequate resource allocation and training to maintain quality of care.


Assuntos
Reanimação Cardiopulmonar , Oxigenação por Membrana Extracorpórea , Adulto , Humanos , Hong Kong , Estudos Retrospectivos , APACHE
4.
Int Nurs Rev ; 66(4): 514-522, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31184377

RESUMO

BACKGROUND: The ageing population and the changing disease profile have been driving the demand for community nurses. However, few nursing students in Singapore aspire to have a career in community nursing following graduation. OBJECTIVES: To explore undergraduate nursing students' perceptions of a career in community nursing and to identify strategies to promote community nursing among nursing students. METHODS: An exploratory qualitative design was used. Four focus group discussions were conducted with a purposive sample of 24 undergraduate nursing students from a university. Interview transcripts were analysed using thematic analysis. FINDINGS: Four key themes emerged as follows: 'mid-life career', 'limited career progression', 'a difficult transition' and 'international nurses-dominated workforce'. DISCUSSION: While most participants rejected a career in community nursing immediately after graduation, they planned to join it at the later stages of their lives to accommodate changing life priorities. Limited career progression and increased difficulty in career transition from community nursing to acute care nursing were identified as deterrent factors in the participants' choices of community nursing as a career. Feelings of marginalization and a lack of role models in community nursing were perceived to be the result of the international nurses-dominated community workforce. CONCLUSION: Community nursing remains an underrated career. There is a need to foster an optimistic career outlook and mobility in community nursing to entice nursing students into this career track. IMPLICATIONS FOR NURSING POLICY: Strategies to enhance community nursing recruitment should focus on providing more quality and diverse community placement opportunities in various community care settings, implementing a clearly defined career developmental plan to elucidate the role of community nurses, and improving community care and cultural competencies to develop a skilled and diverse community nursing workforce.


Assuntos
Escolha da Profissão , Enfermagem em Saúde Comunitária/educação , Estudantes de Enfermagem/psicologia , Mobilidade Ocupacional , Bacharelado em Enfermagem , Feminino , Grupos Focais , Humanos , Masculino , Pesquisa Qualitativa , Singapura , Adulto Jovem
5.
Anaesthesia ; 73(9): 1067-1078, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29974459

RESUMO

Inappropriate dosing of neostigmine for antagonism of neuromuscular blockade has been associated with postoperative pulmonary complications. We evaluated the effects of a quality improvement initiative tailored to optimise the use of neostigmine in antagonising neuromuscular blockade on postoperative pulmonary complications, costs and duration of hospital stay. The quality improvement initiative consisted of: a reduction in available neostigmine aliquot sizes; a cognitive aid; an educational component; and a financial incentive for the intra-operative documentation of train-of-four measurement before administration of neostigmine. We conducted a pre-specified analysis of data obtained in our quality improvement study. Additional analyses were conducted in a propensity-matched cohort. An interrupted time series design was used to discriminate between the intervention and a counterfactual scenario. We analysed 12,025 consecutive surgical cases performed in 2015. Postoperative pulmonary complications occurred in 220 (7.5%) of 2937 cases pre-intervention and 568 (6.3%) of 9088 cases post-intervention. Adjusted regression analyses showed significantly a lower risk of postoperative pulmonary complications (OR 0.73 (95%CI 0.61-0.88); p = 0.001), lower costs (incidence rate ratio 0.95 (95%CI 0.93-0.97); p < 0.001) and shorter duration of hospital stay (incidence rate ratio 0.91 (95%CI 0.87-0.94); p < 0.001) after implementation of the quality improvement initiative. Analyses in a propensity-matched sample (n = 2936 per group) and interrupted time series analysis (n = 27,202 cases) confirmed the findings. Our data show that a local, multifaceted quality improvement initiative can enhance the quality of intra-operative neuromuscular blocking agent utilisation, thereby reducing the incidence of postoperative pulmonary complications.


Assuntos
Inibidores da Colinesterase/administração & dosagem , Pneumopatias/prevenção & controle , Neostigmina/administração & dosagem , Bloqueio Neuromuscular/métodos , Complicações Pós-Operatórias/prevenção & controle , Adulto , Idoso , Inibidores da Colinesterase/efeitos adversos , Inibidores da Colinesterase/farmacologia , Relação Dose-Resposta a Droga , Feminino , Custos Hospitalares/estatística & dados numéricos , Humanos , Tempo de Internação/estatística & dados numéricos , Pneumopatias/induzido quimicamente , Pneumopatias/epidemiologia , Masculino , Massachusetts/epidemiologia , Pessoa de Meia-Idade , Neostigmina/efeitos adversos , Neostigmina/farmacologia , Bloqueio Neuromuscular/economia , Junção Neuromuscular/efeitos dos fármacos , Assistência Perioperatória/métodos , Complicações Pós-Operatórias/induzido quimicamente , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Melhoria de Qualidade/organização & administração , Adulto Jovem
7.
Med J Malaysia ; 73(1): 41-43, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29531201

RESUMO

Procidentia is uncommon condition altering quality of life of young and nulliparous women. Its management poses significant dilemma and challenges as its associated body image, fertility and sexuality issues. Uterine preservation surgery described by Archibald Donald in 1888 known as Manchester -Fothergill procedure seems best option as alternative to vaginal hysterectomy. Despite its increasing popularity among surgeons and patients, robust clinical evidence is needed. We report a case of recurrent procidentia in a young nulliparous woman who had Manchester repair following vaginal sacrospinous hysteropexy. We concluded that Manchester repair is a useful and safe alternative for uterine-preserving technique.


Assuntos
Prolapso Uterino/cirurgia , Útero/cirurgia , Adulto , Feminino , Humanos , Recidiva , Tomografia Computadorizada por Raios X , Ultrassonografia , Prolapso Uterino/diagnóstico por imagem , Útero/diagnóstico por imagem
8.
Anaesthesia ; 72(11): 1334-1343, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28891046

RESUMO

We thought that the rate of postoperative pulmonary complications might be higher after pressure-controlled ventilation than after volume-controlled ventilation. We analysed peri-operative data recorded for 109,360 adults, whose lungs were mechanically ventilated during surgery at three hospitals in Massachusetts, USA. We used multivariable regression and propensity score matching. Postoperative pulmonary complications were more common after pressure-controlled ventilation, odds ratio (95%CI) 1.29 (1.21-1.37), p < 0.001. Tidal volumes and driving pressures were more varied with pressure-controlled ventilation compared with volume-controlled ventilation: mean (SD) variance from the median 1.61 (1.36) ml.kg-1 vs. 1.23 (1.11) ml.kg-1 , p < 0.001; and 3.91 (3.47) cmH2 O vs. 3.40 (2.69) cmH2 O, p < 0.001. The odds ratio (95%CI) of pulmonary complications after pressure-controlled ventilation compared with volume-controlled ventilation at positive end-expiratory pressures < 5 cmH2 O was 1.40 (1.26-1.55) and 1.20 (1.11-1.31) when ≥ 5 cmH2 O, both p < 0.001, a relative risk ratio of 1.17 (1.03-1.33), p = 0.023. The odds ratio (95%CI) of pulmonary complications after pressure-controlled ventilation compared with volume-controlled ventilation at driving pressures of < 19 cmH2 O was 1.37 (1.27-1.48), p < 0.001, and 1.16 (1.04-1.30) when ≥ 19 cmH2 O, p = 0.011, a relative risk ratio of 1.18 (1.07-1.30), p = 0.016. Our data support volume-controlled ventilation during surgery, particularly for patients more likely to suffer postoperative pulmonary complications.


Assuntos
Pneumopatias/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Respiração Artificial/efeitos adversos , Adulto , Idoso , Pressão do Ar , Feminino , Humanos , Ventilação com Pressão Positiva Intermitente , Pneumopatias/etiologia , Medidas de Volume Pulmonar , Masculino , Pessoa de Meia-Idade , Razão de Chances , Respiração com Pressão Positiva , Pontuação de Propensão , Respiração Artificial/estatística & dados numéricos , Medição de Risco , Fatores de Risco , Volume de Ventilação Pulmonar
9.
Epidemiol Infect ; 144(12): 2540-5, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27174845

RESUMO

Prevalence of vancomycin-resistant enterococci (VRE) and use of daptomycin are increasing in Asia. To determine the prevalence of daptomycin non-susceptible enterococci (DNSE) and understand factors associated with reduced daptomycin susceptibility in VRE, we conducted a case-control study in a 1600-bed adult tertiary hospital in Singapore. All VRE isolates from inpatients in 2012 were tested for daptomycin susceptibility. Patients with VRE isolates of daptomycin minimum inhibitory concentration (MIC) ⩾3 µg/ml were classified as daptomycin-reduced susceptible VRE (DRS-VRE) and those with daptomycin MIC 4 µg/ml (DNSE). About half (135, 55%) had reduced susceptibility to daptomycin (MIC 3-4 µg/ml). None in the DS-VRE group had prior exposure to daptomycin. After adjusting for age, gender, comorbidity, hospitalization duration, surgical history, indwelling device use, and duration of antibiotic exposure in the prior 3 months, >1 movement between wards [odds ratio (OR) 0·35, 95% confidence interval (CI) 0·16-0·74, P = 0·006] and minocycline resistance (OR 0·45, 95% CI 0·25-0·84, P = 0·011) were independently associated with DRS-VRE. Our study suggests that daptomycin exposure, >1 movement between wards, and resistance to minocycline, were associated with reduced daptomycin susceptibility in VRE.


Assuntos
Antibacterianos/farmacologia , Daptomicina/farmacologia , Infecções por Bactérias Gram-Positivas/epidemiologia , Resistência a Vancomicina , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Enterococos Resistentes à Vancomicina/fisiologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Risco , Singapura/epidemiologia , Centros de Atenção Terciária
10.
Epidemiol Infect ; 144(6): 1248-56, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26538070

RESUMO

Hospital-acquired methicillin-resistant Staphylococcus aureus (HA-MRSA) is becoming increasingly established in Asian hospitals. The primary aim of this study was to decompose the risk factors for HA-MRSA based on conceptual clinical pathways. The secondary aim was to show the amount of effect attributable to antibiotic exposure and total length of stay before outcome (LBO) so that institutions can manage at-risk patients accordingly. A case-control study consisting of 1200 inpatients was conducted in a large tertiary hospital in Singapore between January and December 2006. Results from the generalized structural equation model (GSEM) show that LBO [adjusted odds ratio (aOR) 14·9, 95% confidence interval (CI) 8·7-25·5], prior hospitalization (aOR 6·2, 95% CI 3·3-11·5), and cumulative antibiotic exposure (aOR 3·5, 95% CI 2·3-5·3), directly affected HA-MRSA acquisition. LBO accounted for the majority of the effects due to age (100%), immunosuppression (67%), and surgery (96%), and to a lesser extent for male gender (22%). Our model enabled us to account and quantify effects of intermediaries. LBO was found to be an important mediator of age, immunosuppression and surgery on MRSA infection. Traditional regression approaches will not only give different conclusions but also underestimate the effects. Hospitals should minimize the hospital stay when possible to reduce the risk of MRSA.


Assuntos
Infecção Hospitalar/epidemiologia , Tempo de Internação , Staphylococcus aureus Resistente à Meticilina/fisiologia , Infecções Estafilocócicas/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Infecção Hospitalar/microbiologia , Feminino , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Pessoa de Meia-Idade , Fatores de Risco , Singapura/epidemiologia , Infecções Estafilocócicas/microbiologia
12.
Pharmazie ; 71(8): 427-433, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442028

RESUMO

Bone diseases such as osteoporosis, osteoarthritis, bone tumours and bone fractures are rather common and not just in the elderly. Parathyroid hormone (PTH) is responsible for maintaining calcium homeostasis, increasing bone mineral density (BMD), increasing cortical and trabecular bone thickness and thus increasing bone strength. Teriparatide (PTH 1-34) has the same effects as endogenous PTH and is pharmacologically used to treat bone diseases such as osteoporosis, osteoarthritis, bone fractures and bone tumours. This review discusses how PTH 1-34 plays a role in managing bone diseases. Clinical studies have shown that short or intermittent dosing of PTH 1-34 has minimal adverse effects, while long-term dosing (over two years) has been linked to de novo osteoarthritis and bone deformation. Currently PTH therapy is only approved in the treatment of post-menopausal osteoporosis, however it is also proven to have effects in treating osteoarthritis, bone tumours and bone fractures. If the patient undergoing therapy is closely monitored, the major pitfalls are very unlikely to take place, thus it is highly recommended that patients be closely monitored by a medical practitioner.


Assuntos
Doenças Ósseas/tratamento farmacológico , Hormônio Paratireóideo/efeitos adversos , Hormônio Paratireóideo/uso terapêutico , Idoso , Conservadores da Densidade Óssea/uso terapêutico , Difosfonatos/uso terapêutico , Humanos , Hormônio Paratireóideo/fisiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
13.
Mol Cell Biol ; 9(8): 3473-81, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2477686

RESUMO

RNA and protein products encoded by the testosterone-repressed prostate message-2 gene (TRPM-2) are induced to high levels, coordinate with the onset of cell death, in numerous rodent models of inducible tissue damage. These models include cell death initiated by hormonal stimuli (prostate regression), pressure insult (renal atrophy after ureteral obstruction), developmental stimuli (necrosis of interdigital tissue), and cytotoxic injury (chemotherapeutic regression of a tumor). Sequence analysis of cDNA encoding TRPM-2 revealed its close homology with a product referred to as SGP-2 or clusterin expressed constitutively by Sertoli cells; however, the immunologically related polypeptides expressed in regressing tissues differ in molecular mass from the forms secreted by the testis. Although the function(s) of the products encoded by the TRPM-2 gene remains unclear, their presence provides a remarkable and early indicator of programmed cell death in many types of mammalian cells.


Assuntos
Sobrevivência Celular , Regulação da Expressão Gênica , Chaperonas Moleculares , Próstata/citologia , Testosterona/fisiologia , Animais , Autorradiografia , Clusterina , Extremidades/embriologia , Feminino , Glicoproteínas/genética , Rim/citologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Hibridização de Ácido Nucleico , RNA , RNA Antissenso , Ratos , Ratos Endogâmicos , Homologia de Sequência do Ácido Nucleico , Células de Sertoli/imunologia , Células de Sertoli/metabolismo , Obstrução Ureteral/patologia , Neoplasias da Bexiga Urinária/genética
14.
Comput Math Methods Med ; 2017: 2610628, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28473865

RESUMO

Medical imaging techniques have widely been in use in the diagnosis and detection of breast cancer. The drawback of applying these techniques is the large time consumption in the manual diagnosis of each image pattern by a professional radiologist. Automated classifiers could substantially upgrade the diagnosis process, in terms of both accuracy and time requirement by distinguishing benign and malignant patterns automatically. Neural network (NN) plays an important role in this respect, especially in the application of breast cancer detection. Despite the large number of publications that describe the utilization of NN in various medical techniques, only a few reviews are available that guide the development of these algorithms to enhance the detection techniques with respect to specificity and sensitivity. The purpose of this review is to analyze the contents of recently published literature with special attention to techniques and states of the art of NN in medical imaging. We discuss the usage of NN in four different medical imaging applications to show that NN is not restricted to few areas of medicine. Types of NN used, along with the various types of feeding data, have been reviewed. We also address hybrid NN adaptation in breast cancer detection.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Detecção Precoce de Câncer , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Algoritmos , Humanos , Processamento de Imagem Assistida por Computador/normas , Sensibilidade e Especificidade
15.
Cancer Res ; 52(16): 4313-9, 1992 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-1353702

RESUMO

Castration initiates extensive apoptosis of the secretory epithelial cells lining the ducts of the rat ventral prostate, resulting in the striking regression of this male sexual accessory tissue. We had previously described the paradox of finding similar cascades of gene activity (c-fos greater than c-myc greater than hsp-70) induced during the early period of ventral prostate regression and during the regrowth of the ventral prostate gland initiated by testosterone replenishment. This common pattern of protooncogene expression during periods of predominant cellular apoptosis or proliferation caused us to examine further the possibility that the two cellular events occur through identical early molecular pathways. In the present study we demonstrate that apoptotic prostate epithelial cells incorporate bromodeoxyuridine into nuclear high-molecular-weight DNA prior to nuclear DNA fragmentation. The DNA synthetic activity occurs in coordination with a massive induction of proliferative cell nuclear antigen, a proliferation marker, in the nuclei of androgen-deprived prostatic epithelial cells. Moreover, this activity is also associated with the increased expression of mRNA encoding p53, a suppressor gene well known as a cell cycle-blocking agent. Our data indicate that quiescent (G0) prostate epithelial cells undergo apoptosis due to two sequential events initiated by testosterone depletion. The first event is the active reentry of these cells into the cell cycle. The second event is the apoptotic destruction resulting from the inability of the differentiated cells to successfully complete this cycle.


Assuntos
Morte Celular/fisiologia , DNA/biossíntese , Proteínas Nucleares/análise , Próstata/fisiopatologia , Fase S/fisiologia , Animais , Southern Blotting , Bromodesoxiuridina/farmacocinética , Morte Celular/genética , Masculino , Desnaturação de Ácido Nucleico , Orquiectomia , Antígeno Nuclear de Célula em Proliferação , Próstata/metabolismo , Próstata/patologia , Ratos , Ratos Endogâmicos , Fase S/genética , Proteína Supressora de Tumor p53/análise , Proteína Supressora de Tumor p53/genética
16.
Eur J Obstet Gynecol Reprod Biol ; 198: 110-115, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26808667

RESUMO

OBJECTIVE: To determine the prevalence of urinary incontinence among primigravida in the third trimester, its risk factors and its effect to quality of life. STUDY DESIGN: This is a cross sectional study involving primigravida in their third trimester of pregnancy, who attended the Patient Assessment Centre of a tertiary referral hospital in Klang Valley from July 2012 to June 2013. The participants were chosen randomly using convenience sampling. A face-to-face interview and a review of their antenatal record were done by trained interviewers. Data on sociodemographic and risk factors were obtained followed by the International Consultation on Incontinence Questionnaire - Short Form (ICIQ-SF). The data was analysed using Statistical Package for Social Science version 20.0. RESULTS: A total of 306 women were involved. The prevalence of urinary incontinence during third trimester was 34.3% (95%CI: 29.0, 39.7). Stress incontinence (64.8%) is the commonest followed by mixed incontinence (24.8%) and urge incontinence (6.7%). Childhood enuresis (p=0.003) and previous history of urinary incontinence (p<0.001) were significantly associated with urinary incontinence. More than 50 percent of women with urinary incontinence in the third trimester felt that it did not affect their daily activities at all. Only 10% of women felt greatly affected by this problem. CONCLUSION: Urinary incontinence is not uncommon among primigravida however many women did not feel that it affected their quality of life. Childhood enuresis and history of urinary incontinence were proven risk factors.


Assuntos
Número de Gestações , Complicações na Gravidez/etiologia , Incontinência Urinária de Urgência/etiologia , Adulto , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Gravidez , Terceiro Trimestre da Gravidez , Fatores de Risco
17.
Neuroscience ; 124(2): 299-304, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14980380

RESUMO

The role of nitric oxide (NO) in post-ischemic cerebral infarction has been extensively examined, but few studies have investigated its role on the neurological deficit. In the present study, we investigated the effect of spermine on the temporal evolution of infarct volume, NO production and neurological deficit using magnetic resonance imaging in a model of permanent focal cerebral ischemia in rats. Spermine given at 10 mg/kg 2 h after ischemia reduced the infarct volume by 40% and abolished brain NO production and improved the neurological score 24 h, 48 h and 72 h after ischemia. Spermine also reduced the neurological deficit as evaluated by rotamex, grip strength and neurological severity score tests.


Assuntos
Comportamento Animal/efeitos dos fármacos , Infarto Encefálico/prevenção & controle , Infarto da Artéria Cerebral Média/tratamento farmacológico , Imageamento por Ressonância Magnética , Doenças do Sistema Nervoso/prevenção & controle , Espermina/uso terapêutico , Análise de Variância , Animais , Química Encefálica/efeitos dos fármacos , Infarto Encefálico/etiologia , Infarto Encefálico/patologia , Mapeamento Encefálico , Modelos Animais de Doenças , Força da Mão , Hemiplegia/tratamento farmacológico , Hemiplegia/etiologia , Hemiplegia/fisiopatologia , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/patologia , Masculino , Doenças do Sistema Nervoso/etiologia , Nitratos/metabolismo , Nitritos/metabolismo , Paresia/tratamento farmacológico , Paresia/etiologia , Paresia/fisiopatologia , Desempenho Psicomotor/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Sais de Tetrazólio , Fatores de Tempo
18.
Neurosurgery ; 46(4): 949-56, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10764270

RESUMO

OBJECTIVE: Animal model systems have shown that head trauma can induce cell death in regions of the brain away from the site of the impact via a process of apoptosis. We sought to determine whether there was evidence of cellular apoptosis in clinically collected materials from human head trauma patients, as well as to attempt to determine the pathway by which it may occur. METHODS: Thirty-one sequential specimens of brain tissue excised during emergency craniotomy for evacuation of cerebral contusions with mass effect were examined. Non-necrotic pericontusional tissues were detected in 11 samples. These were examined for the presence of apoptotic cells by the terminal deoxynucleotide transferase-mediated nick end labeling method as well as by immunohistochemistry to detect possible expression of the apoptosis-related genes p53, bcl-2, and bax. RESULTS: Bax expression was detected in all patients, whereas bcl-2 expression was noted in six patients. Terminal deoxynucleotide transferase-mediated nick end labeling-positive cells were noted in eight patients. One instance of p53-positive immunostaining was observed. Patients with bcl-2 expression had a better survival rate than patients in whom no bcl-2 expression was noted (P = 0.01). CONCLUSION: Although necrosis seemed to be the main finding in cerebral contusions, these results support the hypothesis that apoptosis does occur in patients after traumatic brain injury, and this may contribute to the secondary injury processes that are seen with head injury. Patients in whom anti-apoptotic bcl-2 is induced seem to have a better prognosis. This may have important clinical significance in the development of bcl-2 homologs or bax inhibitors to prevent apoptosis.


Assuntos
Apoptose , Lesões Encefálicas/fisiopatologia , Adulto , Idoso , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Lesões Encefálicas/cirurgia , Estudos de Coortes , Craniotomia , Feminino , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Masculino , Pessoa de Meia-Idade , Necrose , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Análise de Sobrevida , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2
19.
Neurosurgery ; 49(3): 622-6; discussion 626-7, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11523672

RESUMO

OBJECTIVE: Nitric oxide (NO) plays an important role in the pathogenesis of neuronal injury after brain ischemia, and decreased levels of NO have been implicated in the pathogenesis of vasospasm after subarachnoid hemorrhage (SAH). In this study, we measured the ventricular cerebrospinal fluid (CSF) NO levels in patients with SAH and correlated the levels with clinical grade and middle cerebral artery velocities measured with transcranial Doppler ultrasound. METHODS: All patients with spontaneous SAH documented on computed tomography and with an external ventricular drain inserted within 24 hours of hemorrhage were included in the study. A total of 16 patients were studied between August 1999 and August 2000. CSF was collected serially at the time of surgery and subsequently at daily intervals. It was collected during the time that the external ventricular drain remained patent and in situ. NO levels were measured by photometric analysis by using a nitrite/nitrate assay kit (Cayman Chemical, Ann Arbor, MI). RESULTS: The peak NO level in patients with SAH ranged from 9.96 to 168.16 micromol, with a median of 36.93 micromol. The levels were significantly elevated as compared with the control group (5.16 micromol, P < 0.05). The median NO level in patients with poor-grade SAH was 67.14 micromol as compared with 27.42 micromol in patients with good-grade hemorrhage (P < 0.05). No correlation was seen between CSF NO levels and middle cerebral artery velocities. The median NO level was 33.2 micromol in patients with a poor outcome as compared with 30.25 micromol in patients with a good outcome (P > 0.05). CONCLUSION: This study showed that NO levels are elevated after spontaneous SAH, and the degree of elevation is higher in patients with poor-grade SAH.


Assuntos
Infarto da Artéria Cerebral Média/líquido cefalorraquidiano , Infarto da Artéria Cerebral Média/diagnóstico , Neurônios/patologia , Óxido Nítrico/líquido cefalorraquidiano , Hemorragia Subaracnóidea/líquido cefalorraquidiano , Hemorragia Subaracnóidea/diagnóstico , Adulto , Idoso , Velocidade do Fluxo Sanguíneo/fisiologia , Morte Celular , Feminino , Humanos , Infarto da Artéria Cerebral Média/etiologia , Masculino , Pessoa de Meia-Idade , Fotometria/métodos , Índice de Gravidade de Doença , Hemorragia Subaracnóidea/complicações , Tomografia Computadorizada por Raios X , Ultrassonografia Doppler , Vasoespasmo Intracraniano/líquido cefalorraquidiano , Vasoespasmo Intracraniano/diagnóstico , Vasoespasmo Intracraniano/etiologia
20.
Neurosurgery ; 48(2): 359-67; discussion 367-8, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11220380

RESUMO

OBJECTIVE: To further understand the role of angiogenic growth factors in the development of cerebral cavernous malformations (CCMs) and arteriovenous malformations (AVMs), we investigated endothelial cell (EC) expression of receptors for vascular endothelial growth factor (VEGF) and angiopoietin systems in patients with surgically resected lesions. METHODS: Paraffin-embedded sections of five AVMs, CCMs, and normal control brain tissue samples were stained immunohistochemically with antibodies to von Willebrand factor and CD31 (to characterize ECs) and angiogenesis growth factor receptors Flt-1 (VEGF-R1), Flk-1 (VEGF-R2), Tie-1, and Tie-2. We counted large and small vessels in each specimen, assessed each specimen's immunoexpression of each antigen, and analyzed differences between CCMs, AVMs, and the normal control brain tissue samples. RESULTS: The ECs of CCMs, AVMs, and normal control brain tissue samples expressed the von Willebrand factor uniformly, but the ECs of CCMs were largely negative for CD31 (P < 0.05). Flk-1, Flt-1, and Tie-2 were not expressed in the control brain tissue samples. The proportion of immunopositive vessels to VEGF receptors Flk-1 and Flt-1 was significantly greater in AVMs and CCMs than in the control brain tissue samples (P < 0.05). Tie-2 in AVMs and CCMs was expressed in a higher percentage of immunopositive vessels than in the control brain tissue samples, but the difference was not statistically significant. Tie-1 was expressed in rare vessels of all lesion types and control brain tissue samples. CONCLUSION: ECs of CCMs do not seem to express CD31 to the same extent that AVMs and normal brain tissue do. AVMs and CCMs show greater expression of VEGF receptors, but not of angiopoietin receptors, than normal brain tissue does.


Assuntos
Seio Cavernoso/anormalidades , Seio Cavernoso/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Malformações Arteriovenosas Intracranianas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores de Fatores de Crescimento/metabolismo , Adolescente , Adulto , Idoso , Seio Cavernoso/patologia , Criança , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Feminino , Humanos , Imuno-Histoquímica , Malformações Arteriovenosas Intracranianas/patologia , Masculino , Pessoa de Meia-Idade , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Receptor de TIE-1 , Receptor TIE-2 , Receptores de TIE , Receptores de Fatores de Crescimento do Endotélio Vascular , Valores de Referência , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Fator de von Willebrand/metabolismo
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