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1.
Br J Surg ; 108(2): 196-204, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33711132

RESUMO

BACKGROUND: Laparoscopic liver resection for hepatocellular carcinoma (HCC) in Child-Pugh A cirrhosis has been demonstrated as beneficial. However, the role of laparoscopy in Child-Pugh B cirrhosis is undetermined. The aim of this retrospective cohort study was to compare open and laparoscopic resection for HCC with Child-Pugh B cirrhosis. METHODS: Data on liver resections were gathered from 17 centres. A 1 : 1 propensity score matching was performed according to 17 predefined variables. RESULTS: Of 382 available liver resections, 100 laparoscopic and 100 open resections were matched and analysed. The 90-day postoperative mortality rate was similar in open and laparoscopic groups (4.0 versus 2.0 per cent respectively; P = 0.687). Laparoscopy was associated with lower blood loss (median 110 ml versus 400 ml in the open group; P = 0.004), less morbidity (38.0 versus 51.0 per cent respectively; P = 0.041) and fewer major complications (7.0 versus 21.0 per cent; P = 0.010), and ascites was lower on postoperative days 1, 3 and 5. For laparoscopic resections, patients with portal hypertension developed more complications than those without (26 versus 12 per cent respectively; P = 0.002), and patients with a Child-Pugh B9 score had higher morbidity rates than those with B8 and B7 (7 of 8, 10 of 16 and 21 of 76 respectively; P < 0.001). Median hospital stay was 7.5 (range 2-243) days for laparoscopic liver resection and 18 (3-104) days for the open approach (P = 0.058). The 5-year overall survival rate was 47 per cent for open and 65 per cent for laparoscopic resection (P = 0.142). The 5-year disease-free survival rate was 32 and 37 per cent respectively (P = 0.742). CONCLUSION: Patients without preoperative portal hypertension and Child-Pugh B7 cirrhosis may benefit most from laparoscopic liver surgery.


Assuntos
Carcinoma Hepatocelular/cirurgia , Hepatectomia , Laparoscopia , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Intervalo Livre de Doença , Feminino , Hepatectomia/efeitos adversos , Hepatectomia/métodos , Hepatectomia/mortalidade , Humanos , Hipertensão Portal/patologia , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Laparoscopia/mortalidade , Tempo de Internação/estatística & dados numéricos , Cirrose Hepática/patologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Pontuação de Propensão , Estudos Retrospectivos , Índice de Gravidade de Doença , Análise de Sobrevida , Adulto Jovem
3.
Transplant Proc ; 50(10): 3681-3688, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30577255

RESUMO

Our study aimed to determine if a double-dose pre-S containing hepatitis B virus (HBV) vaccination (Sci-B-Vac) could elicit an adequate and sustainable immune response in HBV patients who developed spontaneous hepatitis B surface antibody (anti-HBs) response after liver transplant. PATIENTS AND METHODS: All patients who received transplants for HBV-related disease for >1 year with normal graft function and hepatitis B surface antigen seronegativity were evaluated. They received a 40-µg HBV vaccine if they were responders in our previous vaccine trial, if anti-HBs was positive for >1 year after liver transplant (LT), or if a peak anti-HBs at any time point after LT was >100 mIU/mL. Primary endpoint was the development of anti-HBs ≥ 10 mIU/mL from previous negative value or a 1-log increase from baseline. RESULTS: A total of 86 patients were recruited; 5 were responders from a previous trial; 45 patients had detectable anti-HBs >1 year after LT, and 36 patients had an anti-HBs >100 mIU/mL. All (5/5, 100%) previous responders responded to booster vaccination. For the remaining 81 patients, 10 of 81 (12.3%) responded. CONCLUSION: All previous responders responded to booster vaccination, implying durability and memory of HBV immune response, which is an important prerequisite for definitive host immunity for HBV. In patients who had spontaneous anti-HBs production after LT, a single vaccination can induce response in 12.3% of patients.


Assuntos
Anticorpos Anti-Hepatite B/imunologia , Vacinas contra Hepatite B/administração & dosagem , Hepatite B/prevenção & controle , Imunização Secundária/métodos , Transplante de Fígado , Adulto , Antivirais/uso terapêutico , Feminino , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Humanos , Masculino , Pessoa de Meia-Idade
4.
Transplant Proc ; 50(4): 1087-1093, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29731072

RESUMO

OBJECTIVE: The objective of this study was to compare the long-term outcomes of primary and salvage liver transplantation for patients with hepatocellular carcinoma (HCC). METHOD: This was a 10-year retrospective analysis in a tertiary referral center. RESULTS: There were 184 patients recruited (primary liver transplantation [pLT]:salvage liver transplantation [sLT], 143:41). The median follow-up time was 79 months. Operation time was shorter in the pLT group than the sLT group (661 ± 164 minutes vs 754 ± 206 minutes; P = .01) and the blood loss was 3749 mL and 3545 mL for pLT and sLT, respectively (P = .735). The reoperation rate was 5.6% and 4.9%, respectively (P = 1.0). The 5-year overall and disease-free survival rates from the time of transplantation for pLT and sLT were 84.1% versus 70.2% (P = .01) and 82.2% versus 65.8% (P = .01), respectively. The 5-year overall survival rate from the time of primary treatment for sLT was 80.3% (P = .1). Subgroup analysis of sLT showed that young age (50 vs 56 year old; P = .004) was the only factor associated with poor overall survival. Young age (P = .004) and microvascular permeation (P = .008) in the recurrent tumor were associated with HCC recurrence. Young age stands out to be the only independent factor associated with HCC recurrence. CONCLUSION: sLT is the treatment of choice for patients with recurrent HCC in regions of graft shortage.


Assuntos
Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/métodos , Terapia de Salvação , Carcinoma Hepatocelular/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Transplante de Fígado/efeitos adversos , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/cirurgia , Estudos Retrospectivos , Terapia de Salvação/efeitos adversos , Terapia de Salvação/mortalidade , Taxa de Sobrevida
5.
Br J Surg ; 104(13): 1775-1784, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29091283

RESUMO

BACKGROUND: Hepatic resection and radiofrequency ablation (RFA) are treatment options for early-stage hepatocellular carcinoma (HCC). Whether tumour recurrence and long-term survival favour either treatment has not been established. This randomized trial aimed to test the hypothesis that RFA is superior to hepatic resection in terms of lower tumour recurrence rate and better long-term survival. METHODS: Patients with early-stage HCC (solitary tumour no larger than 5 cm; or no more than 3 tumours, each 3 cm or smaller) were randomized into hepatic resection and RFA groups. Demographic and clinical characteristics, and short- and long-term outcome measures were compared between groups. Primary and secondary outcome measures were overall tumour recurrence and survival respectively. RESULTS: Clinicopathological data were similar in the two groups, which each contained 109 patients. The RFA group had a shorter treatment duration, less blood loss and shorter hospital stay than the resection group. Mortality and morbidity rates were similar in the two groups. The overall tumour recurrence rate was similar in the resection and RFA groups (71·3 versus 81·7 per cent respectively). The 1-, 3-, 5- and 10-year overall survival rates were 94·5, 80·6, 66·5 and 47·6 per cent respectively in the resection group, compared with 95·4, 82·3, 66·4 and 41·8 per cent in the RFA group (P = 0·531). Corresponding disease-free survival rates were 74·1, 50·9, 41·5 and 31·9 per cent in the resection group, and 70·6, 46·6, 33·6 and 18·6 per cent in the RFA group (P = 0·072). CONCLUSION: RFA for early-stage HCC is not superior to hepatic resection, in terms of tumour recurrence, overall survival and disease-free survival. Registration number: HKUCTR-10 (http://www.hkuctr.com).


Assuntos
Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/cirurgia , Ablação por Cateter , Hepatectomia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/cirurgia , Recidiva Local de Neoplasia , Adulto , Idoso , Idoso de 80 Anos ou mais , Perda Sanguínea Cirúrgica , Carcinoma Hepatocelular/patologia , Corantes , Intervalo Livre de Doença , Feminino , Hepatite C/complicações , Hong Kong/epidemiologia , Humanos , Verde de Indocianina , Tempo de Internação , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Adulto Jovem
6.
Hong Kong Med J ; 23(5): 446-53, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28862143

RESUMO

INTRODUCTION: Immunoglobulin G4-related disease remains an under-recognised and evolving disease. Local data are sparse and previous publications have been limited to individual case reports or case series only. We conducted this study to review the clinical features, treatment practices, and factors associated with multisystem involvement in Hong Kong. We described the clinical features and treatment modalities of the largest cohort of immunoglobulin G4-related disease in our locality thus far. METHODS: We retrospectively evaluated all patients with immunoglobulin G4-related disease between January 2003 and December 2015 in Queen Mary Hospital and combined this with patient data extracted from previous local publications. We analysed the clinical features, treatment practices, and factors associated with the number of organ systems involved. RESULTS: A total of 104 patients (55 from Queen Mary Hospital and 49 from literature review) were identified. Patients were predominantly older men (mean [standard deviation] age, 61.9 [12.7] years; male-to-female ratio=3:1) and 94.4% had elevated pre-treatment serum immunoglobulin G4 levels. Hepatobiliary and pancreatic system (40.4%), salivary gland (33.7%), lymph node (29.8%), and eye (19.2%) were the most common organ systems involved. Lymphadenopathy was associated with glucocorticoid use (odds ratio=2.65; 95% confidence interval, 1.08-6.54; P=0.034). Pre-treatment serum immunoglobulin G4 levels correlated with the number of organ systems involved (ß=0.347; P=0.004) and, specifically, more associated with patients having salivary gland involvement than those without (mean, 1109 mg/dL vs 599 mg/dL; P=0.012). CONCLUSION: We identified pre-treatment serum immunoglobulin G4 to be associated with multisystem disease, especially with salivary gland involvement, highlighting its potential for disease prognostication and monitoring. Increased physician awareness and multidisciplinary efforts are required for early diagnosis and optimal management of this masquerading disease.


Assuntos
Imunoglobulina G/sangue , Sarcoidose/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Hong Kong/epidemiologia , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Pâncreas/patologia , Padrões de Prática Médica , Glândulas Salivares/patologia , Sarcoidose/sangue , Sarcoidose/complicações
7.
Asian J Surg ; 40(4): 320-323, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25797563

RESUMO

Cystic artery pseudoaneurysm is a rare condition, which usually arises from the complication of gallstone disease. Patients may present with Quinke's triad (epigastric pain, obstructive jaundice, and gastrointestinal bleeding). The results can be fatal if present with a ruptured pseudoaneurysm. We report a patient who presented with upper gastrointestinal bleeding, and later diagnosis was confirmed with a computer tomography scan of the abdomen and a three-vessel angiogram. Endovascular intervention was attempted. Although it failed, the patient was eventually cured with an open cholecystectomy.


Assuntos
Falso Aneurisma/diagnóstico , Doenças da Vesícula Biliar/diagnóstico , Vesícula Biliar/irrigação sanguínea , Melena/etiologia , Falso Aneurisma/complicações , Artérias , Doenças da Vesícula Biliar/complicações , Humanos , Masculino , Pessoa de Meia-Idade
8.
Hong Kong Med J ; 22(4): 382-92, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27380753

RESUMO

Ultrasound has been developed for therapeutic use in addition to its diagnostic ability. The use of focused ultrasound energy can offer a non-invasive method for tissue ablation, and can therefore be used to treat various solid tumours. High-intensity focused ultrasound is being increasingly used in the treatment of both primary and metastatic tumours as these can be precisely located for ablation. It has been shown to be particularly useful in the treatment of uterine fibroids, and various solid tumours including those of the pancreas and liver. High-intensity focused ultrasound is a valid treatment option for liver tumours in patients with significant medical co-morbidity who are at high risk for surgery or who have relatively poor liver function that may preclude hepatectomy. It has also been used as a form of bridging therapy while patients awaiting cadaveric donor liver transplantation. In this article, we outline the principles of high-intensity focused ultrasound and its clinical applications, including the management protocol development in the treatment of hepatocellular carcinoma in Hong Kong by performing a search on MEDLINE (OVID), EMBASE, and PubMed. The search of these databases ranged from the date of their establishment until December 2015. The search terms used were: high-intensity focused ultrasound, ultrasound, magnetic resonance imaging, liver tumour, hepatocellular carcinoma, pancreas, renal cell carcinoma, prostate cancer, breast cancer, fibroids, bone tumour, atrial fibrillation, glaucoma, Parkinson's disease, essential tremor, and neuropathic pain.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Neoplasias Ósseas/terapia , Encefalopatias/terapia , Neoplasias da Mama/terapia , Protocolos Clínicos , Feminino , Ablação por Ultrassom Focalizado de Alta Intensidade/instrumentação , Humanos , Neoplasias Hepáticas/terapia , Imageamento por Ressonância Magnética , Masculino , Neoplasias Pancreáticas/terapia , Neoplasias da Próstata/terapia
9.
Postgrad Med J ; 92(1085): 123-4, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26917775
10.
Appetite ; 106: 2-12, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-26407803

RESUMO

Food manufacturers and policy makers have been tailoring food product ingredient information to consumers' self-reported preference for natural products and concerns over food additives. Yet, the influence of this ingredient information on consumers remains inconclusive. The current study aimed at examining the first step in such influence, which is consumers' attention to ingredient information on food product packaging. Employing the choice-blindness paradigm, the current study assessed whether participants would detect a covertly made change to the naturalness of ingredient list throughout a product evaluation procedure. Results revealed that only few consumers detected the change on the ingredient lists. Detection was improved when consumers were instructed to judge the naturalness of the product as compared to evaluating the product in general. These findings challenge consumers' self-reported use of ingredient lists as a source of information throughout product evaluations. While most consumers do not attend to ingredient information, this tendency can be slightly improved by prompting their consideration of naturalness. Future research should investigate the reasons for consumers' inattention to ingredient information and develop more effective strategies for conveying information to consumers.


Assuntos
Comportamento de Escolha , Comportamento do Consumidor , Ingredientes de Alimentos , Rotulagem de Alimentos , Embalagem de Alimentos/métodos , Preferências Alimentares/psicologia , Adulto , Atenção , Feminino , Alimentos Orgânicos , Humanos , Masculino , Países Baixos
11.
Transplant Proc ; 47(9): 2768-70, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26680090

RESUMO

Reuse of liver graft for transplantation is extremely uncommon. We report the 1st case of reuse of liver graft from a recipient who had hepatitis B virus (HBV) infection, 11 years after the 1st transplantation. Our relay liver transplantation challenged conventional thinking because of late reuse of graft in the presence of HBV infection. Moreover, both the 1st and the 2nd donors were of advanced age. The key questions were whether the liver graft could be reused safely, especially in the setting of HBV infection, and technical concerns during organ procurement and implantation. The absence of HBV replication was confirmed with negative hepatitis B surface antigen and undetectable serum HBV DNA in the 2nd donor. Based on our experience in managing HBV infection after liver transplantation, we were confident that the adequately suppressed HBV infection in the donor would not jeopardize graft function and that the graft would be able to withstand another ischemia-perfusion injury to continue to function well in our recipient.


Assuntos
Hepatite B/imunologia , Transplante de Fígado/métodos , Transplantes/virologia , Idoso , Morte Encefálica , DNA Viral/sangue , Evolução Fatal , Hepatite B/tratamento farmacológico , Antígenos de Superfície da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Humanos , Transplante de Fígado/classificação , Masculino , Pessoa de Meia-Idade , Reoperação , Coleta de Tecidos e Órgãos , Obtenção de Tecidos e Órgãos , Transplantes/cirurgia , Transplantes/transplante
14.
Invest New Drugs ; 30(6): 2384-90, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22402942

RESUMO

BACKGROUND: The combination of bevacizumab (B) and erlotinib (E) has shown promising clinical outcomes as the first-line treatment of advanced HCC patients. We aimed to evaluate the efficacy and safety of using combination of B + E in treating advanced HCC patients who had failed prior sorafenib treatment. METHODS: Eligible advanced HCC patients with documented radiological evidence of disease progression with sorafenib treatment were recruited. All patients received bevacizumab(B) at 10 mg/kg every 2 weeks with erlotinib(E) at 150 mg daily for a maximum of 6 cycles. Response assessments using both RECIST and modified RECIST criteria were performed after every 6 weeks. The primary endpoint was clinical benefit (CB) rate and a Simon two-stage design was employed. RESULTS: The trial was halted in the first stage according to the pre-set statistical criteria with 10 patients recruited. The median age was 47 years (range, 28-61) and all patients were in ECOG performance status 1. Eighty percent of patients were chronic hepatitis B carriers and all patients had Child A cirrhosis. Among these 10 patients, none of the enrolled patients achieved response or stable disease. The median time-to-progression was 1.81 months (95 % confidence interval [C.I.], 1.08-1.74 months) and overall survival was 4.37 months (95 % C.I., 1.08-11.66 months). Rash (70 %), diarrhea (50 %) and malaise (40 %) were the most commonly encountered toxicities. CONCLUSION: The combination of B + E was well tolerated but had no activity in an unselected sorafenib-refractory advanced HCC population. Condensed abstract The combination of bevacizumab and erlotinib had no clinical activity in sorafenib-refractory HCC population.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Adulto , Anticorpos Monoclonais Humanizados/administração & dosagem , Bevacizumab , Resistencia a Medicamentos Antineoplásicos , Cloridrato de Erlotinib , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Niacinamida/administração & dosagem , Niacinamida/análogos & derivados , Compostos de Fenilureia/administração & dosagem , Quinazolinas/administração & dosagem , Sorafenibe
15.
Scand J Rheumatol ; 39(3): 181-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20166847

RESUMO

OBJECTIVES: To summarize the clinical presentation, histological features, treatment, and outcome of minimal change nephropathy (MCN) in patients with systemic lupus erythematosus (SLE). METHODS: We performed a systematic review of cases of MCN in SLE patients reported in the English literature from January 1985 to May 2009 by a Medline search. RESULTS: The estimated prevalence of MCN in biopsy-proven lupus nephritis is 2.3% in childhood and 1.1% in adults. There are 13 individual cases (12 women, one man) of SLE-related MCN reported in the literature. The mean age of nephritis onset was 32.7 years. In six (46%) patients, MCN was the initial manifestation of SLE. All patients presented with nephrotic syndrome and two (15%) had active urinary sediments. Renal function was impaired in eight (62%) patients and six (46%) patients had active lupus serology. All patients responded promptly to high-dose glucocorticoids but four (31%) had relapse of proteinuria during their course of SLE. None of the patients developed thromboembolic or infective complications. CONCLUSIONS: MCN is an uncommon histological class of lupus nephritis. Typically, patients present with heavy proteinuria, and transient renal dysfunction is common. The prognosis of MCN in SLE appears to be good because of its rapid response to glucocorticoids. Relapses of proteinuria may be reduced by the use of maintenance immunosuppression. Alkylating agents, calcineurin inhibitors, mycophenolate mofetil, and rituximab can be considered in glucocorticoid-dependent or refractory cases of SLE-related MCN.


Assuntos
Nefrite Lúpica/complicações , Células Mesangiais/patologia , Nefrose Lipoide/complicações , Humanos , Nefrite Lúpica/patologia , Nefrite Lúpica/terapia , Nefrose Lipoide/patologia , Nefrose Lipoide/terapia
16.
J Environ Radioact ; 71(3): 215-24, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14613709

RESUMO

Bronchial dosimeters have been designed for adult Chinese males and females for home and mine exposures, which can give the bronchial doses from radon progeny by direct measurements. The bronchial dosimeter for home exposures consists of five 400-mesh wire screens. With a sampling face velocity of 3.3 cm s(-1) for Chinese males and 2.7 cm s(-1) for Chinese females, the deposition pattern on the wire screens were found to satisfactorily match the variation of the dose conversion coefficients (in units of mSv WLM(-1)) with the size of radon progeny from 1 to 1000 nm. The bronchial dosimeter for mine exposures consists of four 250-mesh wire screens. With a sampling face velocity of 3.3 cm s(-1), the deposition pattern on the wire screens were found to satisfactorily match the variation of the dose conversion coefficients for both Chinese males and females. In this way, the bronchial dosimeters directly give the bronchial doses from the alpha counts recorded on the wire-screens.


Assuntos
Exposição por Inalação , Pulmão , Modelos Teóricos , Radiometria/instrumentação , Radiometria/métodos , Radônio/análise , Adulto , China , Etnicidade , Feminino , Humanos , Masculino , Valores de Referência
17.
J Pediatr Surg ; 36(11): 1704-7, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11685706

RESUMO

PURPOSE: The aim of this study was to evaluate the results of laparoscopic treatment of varicocele and findings of testicular volume and blood supply using color Doppler ultrasound scan on follow-up. METHODS: Fourteen patients aged 7 to 15 years old (median, 12.3 years) with left varicocele (grade II, n = 4; grade III, n = 10) underwent laparoscopic clipping of internal testicular vein and artery. At follow-up, both testes were scanned by ultrasonography in axial and longitudinal planes, and at least 3 measurements-length, width, and thickness-were taken to calculate testicular volumes. Arterial perfusion of the testes also was assessed. RESULTS: Operating time ranged from 25 to 80 minutes (mean, 60 minutes). There was no perioperative complication. At a mean follow-up of 14 months (range, 2 to 39 months) all children were asymptomatic with disappearance of varicocele. The volumes of bilateral testes were equal (difference in volumes less than 10%) in 9 children. Ipsilateral testicular hypertrophy was found in 3 children. There was no difference in arterial perfusion between the testes in each patient. Small transient ipsilateral hydrocele was observed in 2 patients. CONCLUSION: Laparoscopic clipping of testicular vein and artery was simple and effective for varicocele treatment and did not compromise testicular blood supply.


Assuntos
Laparoscopia , Instrumentos Cirúrgicos , Varicocele/cirurgia , Adolescente , Artérias , Criança , Seguimentos , Humanos , Masculino , Testículo/irrigação sanguínea , Fatores de Tempo , Ultrassonografia , Varicocele/diagnóstico por imagem , Veias
18.
Appl Radiat Isot ; 55(5): 707-13, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11573806

RESUMO

A true bronchial dosimeter has been designed, consisting of four 400-mesh wire screens and a filter paper. With a face velocity of 3.3 cm s(-1) for home exposure and 4.6 cm s(-1) for mine exposure, the deposition pattern on the wire screens were found to satisfactorily match the variation of the dose conversion factor (in units of mSv WL M(-1)) with the size of radon progeny from 1 to 1000 nm. In this way, the bronchial dosimeter directly gives bronchial dose from the alpha counts recorded on the wire-screens and the filter paper. Calculations of the dose conversion coefficient (DCC) using the proposed bronchial dosimeter and the lung dosimetric model were performed for typical aerosol characteristics. Values obtained from the bronchial dosimeter yielded overestimates of the DCC by 11.1% and 2.4% for typical home and mine conditions, respectively.


Assuntos
Brônquios/efeitos da radiação , Radiometria/instrumentação , Produtos de Decaimento de Radônio/efeitos adversos , Exposição Ambiental , Desenho de Equipamento , Humanos , Modelos Teóricos , Exposição Ocupacional
19.
J Environ Radioact ; 56(3): 327-40, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11468823

RESUMO

The airway dimensions for Caucasian males have been scaled by multiplying by factors 0.95 and 0.88 to give those for Chinese males and females, respectively. Employing the most recent data on physical and biological parameters, the radiation doses to the basal and secretory cells due to alpha particles from 218Po and 214Po, homogeneously distributed in the mucous layer, have been calculated. The emission of alpha particles has been simulated by a Monte Carlo method. For both basal and secretory cells, the dose conversion coefficients (DCCs) for physical conditions of sleep, rest, light and heavy exercise, have been obtained for Chinese males and females for unattached progeny, and for attached progeny of diameters 0.02, 0.15, 0.25, 0.30 and 0.50 micron. For basal cells, the coefficients lie in the range 0.69-6.82 mGy/(Js/m3) or 8.7-86 mGy/WLM for unattached progeny and in the range 0.045-1.98 mGy/(Js/m3) or 0.57-25 mGy/WLM for attached progeny. The corresponding ranges for Caucasian males are 1.27-8.81 mGy/(Js/m3) or 16-111 mGy/WLM-1 and 0.05-2.30 mGy/(Js/m3) or 0.64-29 mGy/WLM. For secretory cells, the coefficients lie in the range 0.095-16.82 mGy/(Js/m3) (1.2-212 mGy/WLM) for unattached progeny and in the range 0.095-6.67 mGy/(Js/m3) (1.2-84 mGy/WLM) for attached progeny. The corresponding ranges for Caucasian males are 0.34-21.51 mGy/(Js/m3) (4.3-271 mGy/WLM) and 0.1-7.78 mGy/(Js/m3) (1.3-98 mGy/WLM). The overall DCCs calculated for a typical home environment are 0.59 and 0.52 mSv/(Js/m3) (7.4 and 6.5 mSv/WLM) for Chinese males and females, respectively, which are 80 and 70% of the value, 0.73 mSv/(Js/m3) (9.2 mSv/WLM), for Caucasian males.


Assuntos
Povo Asiático , Carcinógenos Ambientais/farmacocinética , Pulmão/química , Produtos de Decaimento de Radônio/farmacocinética , População Branca , Atividades Cotidianas , Antropometria , Peso Corporal , Carcinógenos Ambientais/análise , Exercício Físico , Feminino , Humanos , Masculino , Radiometria , Produtos de Decaimento de Radônio/análise , Valores de Referência , Fatores Sexuais , Sono
20.
Ann Neurol ; 36(6): 903-11, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7998778

RESUMO

The 4-kd amyloid beta protein (A beta) deposited as amyloid in Alzheimer's disease (AD) is produced and released by normal proteolytic processing of the amyloid beta protein precursor (beta APP) and is readily detected in cerebrospinal fluid (CSF). Here, we present the levels of A beta in CSF from a total of 95 subjects, including 38 patients with AD, 14 with early-onset AD and 24 with late-onset AD, 25 normal control subjects, and 32 patients with other neurological diseases. The level of A beta decreased with normal aging, and there was a significant elevation in the level of A beta in the CSF of early-onset AD patients (4.14 +/- 1.37 pmol/ml, p < 0.01). Neither Mini-Mental State nor Functional Assessment Staging were correlated with the amount of A beta in the CSF. The A beta/secreted form of beta APP ratio was elevated, but the level of alpha 1-antichymotrypsin in the CSF did not correlate with the level of CSF A beta in early-onset AD patients. Thus, the level of A beta in the CSF is elevated in early-onset AD patients and is suggested to be correlated with the pathology in the brain that characterizes AD.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Precursor de Proteína beta-Amiloide/líquido cefalorraquidiano , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , alfa 1-Antiquimotripsina/líquido cefalorraquidiano
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