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1.
J Altern Complement Med ; 9(5): 641-9, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14629842

RESUMO

OBJECTIVES: To examine the relative effectiveness of electro-acupuncture (EA) and transcutaneous electrical nerve stimulation (TENS) in alleviating osteoarthritic (OA)-induced knee pain. DESIGN: Single-blinded, randomized controlled study. SUBJECTS: Twenty-four (24) subjects (23 women and 1 man), mean age 85, were recruited from eight subsidized Care & Attention Homes for the elderly. INTERVENTIONS: Subjects were randomly assigned to the EA, TENS, or control groups. Subjects in the EA group (n = 8) received low-frequency EA (2 Hz) on two acupuncture points (ST-35, Dubi and EX-LE-4, Neixiyan) of the painful knee for 20 minutes. Subjects in the TENS group (n = 8) received low-frequency TENS of 2 Hz and pulse width of 200 micros on the same acupuncture points for 20 minutes. In both treatment groups, electrical treatment was carried out for a total of eight sessions in 2 weeks. Eight subjects received osteoarthritic knee care and education only in a control group. All subjects were evaluated before the first treatment, after the last treatment, and at 2-week follow-up periods. RESULTS: After eight sessions of treatment, there was significant reduction of knee pain in both EA group and TENS group, as measured by the Numeric Rating Scale (NRS) of pain (p < 0.01). Prolonged analgesic effect was maintained in the EA and the TENS groups at a 2-week follow-up evaluation. The Timed Up-and-Go Test (TUGT) score of the EA group was significantly lower than that of the control group (p < 0.05), but such change was not observed in the TENS group. CONCLUSIONS: Both EA and TENS treatments were effective in reducing OA-induced knee pain. EA had the additional advantage of enhancing the TUGT results as opposed to TENS treatment or no treatment, which did not produce such corollary effect.


Assuntos
Eletroacupuntura , Osteoartrite do Joelho/terapia , Manejo da Dor , Estimulação Elétrica Nervosa Transcutânea , Pontos de Acupuntura , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Distribuição de Qui-Quadrado , Eletroacupuntura/métodos , Feminino , Seguimentos , Humanos , Masculino , Dor/etiologia , Medição da Dor , Método Simples-Cego , Fatores de Tempo , Estimulação Elétrica Nervosa Transcutânea/métodos , Resultado do Tratamento
2.
Eur J Ophthalmol ; 13(2): 147-50, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12696633

RESUMO

PURPOSE: To describe the clinic-pathological analysis of the visually significant opacification of the Cirrus International Hydroflex foldable hydrophilic acrylic intraocular lens (IOL) (model SC600-2, Medical Developmental Research Inc., Clearwater, Florida) and to highlight that this IOL is the same model as the Acryflex SC600-2 IOL, by the same manufacturer. METHODS: Retrospective review of five eyes of four patients with opacification of their Cirrus International Hydroflex foldable hydrophilic acrylic IOLs (model SC600-2) after uncomplicated phacoemulsification and IOL implantation. Two IOLs were explanted from two patients 14 to 24 months after initial implantation. Each explanted lens was divided into equal halves, one half for scanning electron microscopy (SEM) study and the other half for transmission electron microscopy (TEM) examination. SEM and TEM samples were also subjected to energy dispersive X-ray analysis (EDX). RESULTS: The IOL opacification was detected 14 to 24 months after uncomplicated phacoemulsification and IOL implantation. EDX analysis showed that the crystals contained calcium and phosphorus, presumably calcium phosphate. CONCLUSIONS: The Cirrus International Hydroflex foldable hydrophilic acrylic IOL (model SC600-2) is associated with opacification, that appeared worse centrally than peripherally. This is the same model as the Acryflex SC600-2 IOL, made by the same manufacturer. The opacification consists of calcium and phosphate.


Assuntos
Resinas Acrílicas/efeitos adversos , Materiais Biocompatíveis/efeitos adversos , Calcinose/etiologia , Calcinose/patologia , Lentes Intraoculares/efeitos adversos , Falha de Prótese , Calcinose/metabolismo , Cálcio/análise , Remoção de Dispositivo , Microanálise por Sonda Eletrônica , Humanos , Implante de Lente Intraocular , Microscopia Eletrônica de Varredura , Facoemulsificação , Fósforo/análise , Estudos Retrospectivos
3.
J Med Virol ; 62(3): 364-76, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11055247

RESUMO

Polyclonal antibodies derived from dengue virus immune sera and 3H5 monoclonal antibody showed potent neutralisation effect on dengue-2 virus in the plaque reduction neutralisation assay. This study demonstrated that antibodies present in immune human sera and 3H5 monoclonal antibody neutralised dengue-2 virus by altering the virus entry pathway into cells. In the presence of neutralising antibodies, dengue-2 virus was endocytosed by LLC-MK2 cells. The endocytosis process involved ruffling of antibody-coated virions by cellular pseudopodia and invagination of cell membrane. This mode of entry is atypical as compared to direct fusion of dengue-2 virus with cell membrane in the absence of antibody. The virions were internalised in the form of virion-antibody complexes consisting of single or clumps of virions. After 3 minutes of incubation, neutralised virions were detected in cellular vesicles, and signs of intra-endosomal penetration into cytoplasm were not evident even after a prolonged incubation of 10 minutes, suggesting that viral uncoating was compromised. Vesicle-bound virions were no longer detected after 20 minutes of incubation. In addition, no sign of viral replication was detected in cells infected with "neutralised" virions by immunofluorescence assay. This indicated that internalised virions had been degraded leading to abortive infection. In conclusion, antibodies present in 3H5 monoclonal antibody and human immune sera rendered dengue-2 virus non-infective by neutralising the viral fusion site and causing alteration of viral entry mode. Antibodies in immune sera but not 3H5 monoclonal antibody also exerted minimal inhibitory effect on virus binding and internalisation.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Vírus da Dengue/imunologia , Anticorpos Monoclonais/metabolismo , Anticorpos Antivirais/metabolismo , Linhagem Celular , Vírus da Dengue/isolamento & purificação , Glicoproteínas/imunologia , Humanos , Microscopia Eletrônica , Testes de Neutralização , Fatores de Tempo , Vírion/imunologia , Vírion/isolamento & purificação
4.
Epilepsia ; 40(10): 1370-7, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10528931

RESUMO

PURPOSE: Reproductive dysfunction and endocrine disorders are common among women with temporal lobe epilepsy. This study used the kindled rat model to test the hypothesis that limbic seizures directly contribute to reproductive dysfunction. METHODS: Kindling electrodes were implanted in the basolateral amygdala in adult female rats. Females were kindled by either brief, daily, suprathreshold stimulations with a bipolar electrode or sham-kindled (controls). Electrographic and behavioral seizures were monitored. Estrous cycles also were monitored with daily vaginal smears. RESULTS: Seizures arrested ovarian cyclicity in all (n = 42) kindled animals, the rats exhibiting persistent vaginal cornification (PVC). In these animals PVC was associated with high serum estradiol, increased pituitary weight, and polyfollicular ovaries consisting of many cystic follicles, as well as follicles in various stages of growth and atresia. In 93% of females, this effect occurred after the development of stage 5 motor seizures, when focal seizures had secondarily generalized. In contrast, only five (21%) of 24 sham-kindled controls exhibited PVC. A single injection of progesterone (P4) temporarily restored cyclicity in five (18%) of 28 kindled females exhibiting PVC. In contrast, P4 administration restored cyclicity in all five sham-kindled controls that had spontaneously stopped cycling. P4 treatment to kindled females in PVC resulted in a different endocrine profile than that in non-P4-treated, kindled rats in PVC. P4-treated rats had high serum estradiol, testosterone, and prolactin levels; they showed an increase in pituitary weight; and their ovaries contained numerous corpora lutea and cystic follicles surrounded by markedly overdeveloped thecal cell layers. CONCLUSIONS: Seizures initiated in the amygdala result in impairment of the hypothalamic-pituitary axis, resulting in loss of ovarian cyclicity.


Assuntos
Tonsila do Cerebelo/fisiologia , Excitação Neurológica/fisiologia , Ovário/fisiologia , Síndrome do Ovário Policístico/etiologia , Convulsões/etiologia , Animais , Estimulação Elétrica , Estradiol/sangue , Estro/efeitos dos fármacos , Estro/fisiologia , Feminino , Tamanho do Órgão , Ovário/efeitos dos fármacos , Ovário/patologia , Ovulação/efeitos dos fármacos , Hipófise/anatomia & histologia , Hipófise/efeitos dos fármacos , Síndrome do Ovário Policístico/patologia , Progesterona/farmacologia , Prolactina/sangue , Ratos , Convulsões/patologia , Testosterona/sangue , Vagina/efeitos dos fármacos , Vagina/patologia
5.
J Med Virol ; 57(3): 322-30, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10022806

RESUMO

The Western blot (WB) assay was used to determine dengue virus antibodies present in human immune sera arising from recent primary and secondary dengue virus infections in Singapore. Cell lysates of dengue-2 virus-infected C6/36 and Vero cells were used. Antibodies directed against structural proteins of dengue-2 virus including envelope (E, gp60/50), capsid-premembrane (C-PrM, gp35), and premembrane (PrM, gp20) were detected, with antibody against envelope protein being most dominant. Similar WB profiles were detected in both primary and secondary dengue virus infections. The reactivity rate of antibodies to dengue-2 virus proteins was higher in infected Vero cell lysate than in infected C6/36 cell lysate, with the exception of antibodies to nonstructural proteins of NS1 and NS3, which were detected predominantly in infected C6/36 cell lysate. More than 75% of "normal" individuals (with no complaint of recent dengue virus infection) examined had low levels of dengue virus antibodies, but all presented with similar WB profiles as patients with recent dengue virus infections. This finding reflects a high seroprevalence of dengue virus infections and the long lasting nature of E, C-PrM, and PrM antibodies. Results from this study indicate that in natural dengue virus infections, native E, C-PrM, and PrM antigens of dengue virus are immunogenic and elicit long-lasting antibodies.


Assuntos
Anticorpos Antivirais/imunologia , Western Blotting , Dengue/imunologia , Animais , Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , Western Blotting/métodos , Chlorocebus aethiops , Dengue/sangue , Testes de Inibição da Hemaglutinação , Hospitalização , Humanos , Imunoglobulina M/imunologia , Estudos Retrospectivos , Células Vero
6.
Aust Fam Physician ; 27(7): 615-8, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9679383

RESUMO

BACKGROUND: The overall incidence of tuberculosis (TB) in the general Australian population is low and has been stable over the past 10 years. The incidence is, however, much higher in certain subgroups of the population and these include overseas-born people (especially from countries in Asia) and Aboriginal and Torres Strait Islander populations. Other groups regarded as at increased risk of TB are nursing home residents, the homeless, prison populations and immunosuppressed patients, especially those who are HIV positive. OBJECTIVE: Patients regarded as high risk should be investigated promptly if they present with signs or symptoms suggestive of TB. DISCUSSION: The best method of preventing the transmission of TB and preventing the emergence of drug resistant strains of the organism are by ensuring that sputum smear positive patients are isolated till non-infectious; that any patient with TB receives prompt and adequate treatment; that all patients with TB comply with a full course of treatment till cured: and that contact tracing is undertaken to detect newly infected patients so as to offer chemoprophylaxis and to detect previously unrecognised cases.


Assuntos
Tuberculose , Adolescente , Adulto , Idoso , Austrália/epidemiologia , Vacina BCG/uso terapêutico , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Teste Tuberculínico , Tuberculose/diagnóstico , Tuberculose/tratamento farmacológico , Tuberculose/epidemiologia , Tuberculose/prevenção & controle , Tuberculose Pulmonar/diagnóstico
7.
J Mol Recognit ; 9(2): 143-8, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8877806

RESUMO

Seven new steroidal polyamines derived from bile acids, either lithocholic or deoxycholic acid, have been studied as DNA-binding agents using four complimentary methods: an ethidium displacement assay, observed changes in the thermal denaturation of poly[d(AT)], effects on hyperchromicity of DNA, and circular dichroism. In addition, modelling studies were conducted to examine the electrostatic surface potential of the polycations. The results point to a key role for a large hydrophobic surface area on the steroid in addition to the Coulombic attraction by ammonium and guanidinium groups on the steroid interacting with the polyphosphate backbone.


Assuntos
DNA/metabolismo , Modelos Químicos , Poliaminas/química , Poliaminas/metabolismo , Ácidos e Sais Biliares/química , Cátions , Dicroísmo Circular , DNA/química , Etídio/química , Etídio/metabolismo , Guanidina , Guanidinas/química , Modelos Moleculares , Conformação de Ácido Nucleico , Ácidos Nucleicos Heteroduplexes , Compostos de Amônio Quaternário/química , Relação Estrutura-Atividade , Temperatura
8.
J Surg Oncol ; 61(2): 134-7, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8606545

RESUMO

For hepatocellular carcinoma, the peak age of patients is at the sixth decade. However, the influence of age on the tumor biologic behavior and long-term patient survival is controversial. We retrospectively studied 278 patients whose hepatocellular carcinomas were surgically resected to analyze the pathologic and clinical features of the tumors and patient survival in relation to age. The patients were divided into two groups, younger than 50 years of age and older than 50 years. Ninety-seven patients were 50 years of age or under, and 181 were older than 50 years. The younger patients had: (1) more frequent hepatitis B surface antigen positivity (P = 0.022), (2) less cirrhosis (P = 0.050), (3) less tumor encapsulation, (4) a more advanced tumor stage in terms of more venous permeation (P = 0.012), more liver invasion (P = 0.010) and larger tumor (P = 0.002), and (5) a more frequently raised serum alpha-fetoprotein level (P = 0.035). In spite of the more advanced stage of the tumors, both the actuarial and disease-free survival rates did not differ significantly from those of the older group. The operative mortality rates also were similar in both groups. To conclude, there were distinct differences in the clinical and pathologic features of the tumors of patients < 50 years and those older. Although the tumors were more advanced in the younger group, the less frequently associated cirrhosis in this group might have partly compensated to result in survival rates similar to those of the older group. Because of the comparable survival rates, the treatment policy in the older group should not differ greatly from that in the younger group.


Assuntos
Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Adulto , Fatores Etários , Idoso , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/virologia , Intervalo Livre de Doença , Feminino , Antígenos de Superfície da Hepatite B/análise , Humanos , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida
9.
Cancer ; 76(12): 2443-8, 1995 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-8625069

RESUMO

BACKGROUND: In patients with hepatocellular carcinoma, surgical resection may offer a chance of cure. However, tumor recurrence is not infrequent after resection. METHODS: To identify the pathologic factors that are of prognostic significance and predictive value in tumor recurrence, the authors studied 278 patients (243 men, 35 women) who had hepatectomy for hepatocellular carcinoma. Disease free and actuarial survival were correlated with 20 pathologic parameters of the resected specimens using multivariate analysis. RESULTS: The median follow-up period was 23.6 months. The overall disease free survival rates at 1, 3 and 5 years were 42%, 23%, and 17%, respectively, and the overall actuarial survival rates for the corresponding time periods were 70%, 39%, and 28%, respectively. The results indicated that tumor encapsulation (P = 0.004) and heavy intratumor inflammatory infiltrates (P = 0.003) were independent favorable factors related to tumor recurrence. Negative resection margins (P = 0.001) and heavy intratumor inflammatory infiltrates (P = 0.003) were independent favorable factors correlated with survival. CONCLUSIONS: From this analysis, it was determined that detailed histologic examination of resected specimens of hepatocellular carcinoma is important in assessing long term prognosis and stratification of patients for treatment.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Análise Atuarial , Adulto , Idoso , Carcinoma Hepatocelular/cirurgia , Intervalo Livre de Doença , Feminino , Hepatectomia , Humanos , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia , Valor Preditivo dos Testes , Prognóstico , Fatores de Risco , Análise de Sobrevida , Resultado do Tratamento
10.
J Gastroenterol Hepatol ; 10(5): 570-6, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8963033

RESUMO

To examine the relationship between society stress and peptic ulcer perforation, time-trend analysis was performed on the annual incidence of perforated peptic ulcer per 100,000 population in Hong Kong during the years 1962-85, when Hong Kong, as a developing city, went through significant socio-economic and political changes, and the trend was correlated with specially designed and validated society stress scores estimated annually during the same period. The society stress scores were derived independently by two expert panels blinded to the purpose of the study, one selecting and categorizing negative news events for Hong Kong during this period, and the other weighing the categories and scoring the impact of the news on Hong Kong. The incidence of perforation increased significantly during the years and manifested three distinct peaks, which coincided with the worst economic recession in Hong Kong, the influx of mainlander Chinese and Vietnamese boat people, and the Sino-British negotiation on the sovereignty of Hong Kong after 1997. Both linear and autoregression analysis, the latter taking into consideration point fluctuations in rates, showed that perforation rates correlated significantly with the society stress scores (r = 0.57, P < 0.002). The peak effects and the significant correlations indicate that an association exists between society stress and peptic ulcer perforation, and suggest that chronic society stress plays an important role in the aetiology of this condition, although the relatively low r value also suggests the presence of other aetiological factors.


Assuntos
Úlcera Péptica Perfurada/etiologia , Estresse Psicológico/complicações , Adulto , Feminino , Hong Kong , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Úlcera Péptica Perfurada/epidemiologia , Fatores Socioeconômicos
11.
Australas Radiol ; 39(3): 249-53, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7487759

RESUMO

The imaging appearances of three patients with variable clinical presentations of dissecting neuropathic joints are described. Plain radiographs demonstrated bony debris within the soft tissues adjacent to and distant from neuropathic joints. Computed tomography combined with arthrography confirmed that the soft tissue bony debris communicated with the joints.


Assuntos
Artropatia Neurogênica/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso , Articulação do Tornozelo/diagnóstico por imagem , Artrografia , Articulação do Cotovelo/diagnóstico por imagem , Feminino , Humanos , Articulação do Joelho/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Articulação do Ombro/diagnóstico por imagem , Coxa da Perna/diagnóstico por imagem
12.
Cancer ; 75(1): 18-22, 1995 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-7804971

RESUMO

BACKGROUND: Hepatocellular carcinoma is notably more prevalent in men than in women. METHODS: To examine the sex-related characteristics of patients with primary hepatocellular carcinoma, 35 women were compared with 243 men, both groups having undergone surgical resection of the tumor. RESULTS: Women had a lower incidence of tumor recurrence, with median disease free survival of 19.5 months compared with 4.5 months for men (P < 0.001). Women also had more favorable actuarial survival than men [36.5 months for women compared with 12.4 months for men (P = 0.002)]. Women had a significantly higher incidence (80%) of tumor encapsulation than men (45%) (P < 0.001). Furthermore, the tumors in women were frequently less invasive in terms of lower incidence of tumor microsatellites, liver invasion, and positive histologic margin. Tumor microsatellite formation was present with 16% of tumors in women, compared with 60% for men (P < 0.0001). Liver invasion was found in 37% of tumors in women and 61% in men (P = 0.03). Only 6% of tumors in women had a positive histologic margin, compared to 24% in men (P = 0.04). There was no statistical significance in the incidence of cirrhosis in the nontumorous liver, hepatitis B surface antigen positivity, mean age, or tumor size, between women and men. CONCLUSIONS: Women who had hepatocellular carcinoma and hepatic resection had better survival rates and a lower rate of tumor recurrence than male patients. The better prognosis in women with hepatocellular carcinoma appeared to be related to the pathobiologic characteristics of the tumor (i.e., frequent encapsulation and lower tumor invasiveness).


Assuntos
Carcinoma Hepatocelular/mortalidade , Neoplasias Hepáticas/mortalidade , Adulto , Idoso , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Cirrose Hepática/complicações , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Caracteres Sexuais , Análise de Sobrevida
13.
Biochemistry ; 33(40): 12119-26, 1994 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-7918433

RESUMO

Isoguanosine has been incorporated into a 34-mer hammerhead ribozyme by the solid-phase phosphoramidite method, using an acetamidine base protecting group. The activity of the hammerhead ribozyme when singly mutated to isoguanosine at the adenosine positions 6, 9, and 13 was 1-2-fold less than the wild-type activity. Mutations to 2-aminopurine ribonucleoside at positions 9 and 13 were 5-fold reduced in activity, but that at position 6 was approximately 30-fold reduced. These results support the view that the 6-amino functions of A6, A9, and A13 are not very important for catalysis. The 2-position of A6 tolerates a carbonyl function but not an amino group, whereas A9 and A13 tolerate both functional groups. The tolerance of a 2-amino group at A9 and A13 makes G(anti)/A(anti) Watson-Crick type base mispairing for G12/A9 and A13/G8 unlikely.


Assuntos
Adenosina/química , Guanosina/química , Oligodesoxirribonucleotídeos/síntese química , RNA Catalítico/química , 2-Aminopurina/química , Adenosina/genética , Adenosina/metabolismo , Amidinas/química , Sequência de Bases , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Eletroforese em Gel de Poliacrilamida , Guanosina/genética , Guanosina/metabolismo , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Mutação/genética , Oligodesoxirribonucleotídeos/química , RNA Catalítico/genética , RNA Catalítico/metabolismo , Relação Estrutura-Atividade , Inibidores da Tripsina/química
14.
Cancer ; 74(1): 30-7, 1994 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-8004579

RESUMO

BACKGROUND: Gene deletion, point mutations, and abnormalities in expression of the tumor suppressor gene p53 in hepatocellular carcinoma have been reported to occur with varying frequency in different geographic regions. METHODS: To assess the expression and point mutation of the p53 gene, 31 patients with hepatocellular carcinomas were examined using Northern blotting, immunohistochemical methods, and DNA sequencing. All patients were Chinese, and 90.3% were positive for hepatitis B surface antigen (HBsAg). RESULTS: p53 transcript or protein was found in 14 (48.4%) of the 31 patients. Detectable p53 mRNA transcripts were found in 10 patients, and p53 protein was detected in 8 patients. In most cases of patients who had detectable p53 mRNA transcripts, the transcripts in the tumors were exhibited at a higher level than they were in the corresponding nontumorous livers. No p53 protein was detected in the nontumorous livers in all 31 patients. Six (23.1%) of the 26 tumors sequenced showed point mutation scattered in exons 5-9. Of these, only two were at codon-249, and the nature of these two mutations was G-to-T transversions. All but one of the six patients with point mutations had overexpression of the gene. CONCLUSIONS: Our results show that scattered point mutations are not uncommon in hepatocellular carcinomas in patients from Hong Kong. The distribution pattern of the mutations seems to have no particular correlation with HBsAg status despite a high prevalence rate of HBsAg positivity in our patients. Consistent with a low aflatoxin exposure, aflatoxin-related specific mutation at codon-249 is much less related to the pathogenesis of hepatocellular carcinoma in Hong Kong Chinese people than in other regions with a high-aflatoxin exposure.


Assuntos
Carcinoma Hepatocelular/genética , Expressão Gênica , Genes p53/genética , Neoplasias Hepáticas/genética , Mutação Puntual , Adulto , Idoso , Northern Blotting , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/etnologia , China/etnologia , Análise Mutacional de DNA , DNA de Neoplasias/análise , Feminino , Hepatite B/complicações , Hong Kong , Humanos , Imuno-Histoquímica , Hibridização In Situ , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/etnologia , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/análise , Proteína Supressora de Tumor p53/análise , Proteína Supressora de Tumor p53/genética
15.
Am J Clin Pathol ; 102(1): 80-6, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8037171

RESUMO

To examine the prognostic and pathobiologic significance of DNA content, the authors studied the surgically resected hepatocellular carcinomas of 69 patients by flow cytometric analysis. Homogeneity of DNA content within individual tumor nodules was present in 15 (88%) of 17 specimens examined. Similarly, homogeneity of DNA content in tumors having multiple nodules was found in 8 (73%) of 11 specimens. In 64 tumors with homogeneous DNA content evaluated further, DNA aneuploidy was present in 30 (46.9%) specimens, and the proportion of aneuploid tumors was similar in the large (> 5 cm in diameter, n = 35) and small (< or = 5 cm, n = 25) lesions, at 42.9% and 40%, respectively. Overall, the diploid tumors had serum alpha-fetoprotein levels increased to greater than 500 micrograms/mL more frequently than did the aneuploid tumors (P = .037). DNA content did not correlate significantly with hepatitis B surface antigen, presence of liver cirrhosis, cellular differentiation, tumor size, or tumor encapsulation. DNA content also did not influence tumor invasiveness in terms of liver invasion, presence of tumor microsatellites, or venous permeation. With multivariate Cox regression analysis, tumor encapsulation (P = .015), negative resection margin (P = .007), and DNA ploidy pattern stratified according to large and small tumors (P = .024) were favorable prognostic factors. In the small tumors, a diploid DNA pattern was associated with significantly better patient survival than was an aneuploid pattern (P = .012). In the large tumors, on the contrary, a diploid pattern was associated with poorer patient survival than was an aneuploid pattern (P = .029). The authors conclude that DNA ploidy pattern in hepatocellular carcinomas is homogeneous and stable. It supplements other predictors in prognostication when the lesions are stratified into small and large ones by tumor size. It is of particular importance as a predictor because it can be assessed preoperatively in needle-biopsy specimens.


Assuntos
Carcinoma Hepatocelular/genética , DNA de Neoplasias/análise , Neoplasias Hepáticas/genética , Ploidias , Adulto , Idoso , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Feminino , Citometria de Fluxo , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida
16.
Biochemistry ; 32(43): 11658-68, 1993 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-8218233

RESUMO

The three guanosines of the central core of a hammerhead ribozyme were replaced by 2-aminopurine ribonucleoside, xanthosine, isoguanosine, inosine, and deoxyguanosine. These analogues were incorporated by automated solid-phase synthesis, with the exception of isoguanosine. This was introduced by ligating a donor, which carried the isoguanosine at its 5'-end, and an acceptor oligoribonucleotide by a T4 DNA ligase-catalyzed reaction. Most of these modifications lowered the rate constant of cleavage by the hammerhead ribozyme drastically. Inspection of the possible hydrogen-bonding interactions disturbed by these modifications suggests that there is no G12A9 or A13G8 mismatched base pair in the central region. Increasing the Mg2+ concentration from 10 to 50 mM did not enhance these rates appreciably. This makes it improbable that the guanosines, including their 2'-hydroxyl groups, are involved in the binding of the catalytically active Mg2+. Transition-state destabilizing energies of 0.6-4.7 kcal mol-1 suggest that essentially all guanosines are involved in a hydrogen-bonding network.


Assuntos
RNA Catalítico/química , Bacteriófago T4/enzimologia , Sequência de Bases , DNA Ligases/metabolismo , Guanosina/metabolismo , Ligação de Hidrogênio , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Oligorribonucleotídeos/síntese química , Oligorribonucleotídeos/metabolismo , RNA Catalítico/metabolismo , Relação Estrutura-Atividade , Termodinâmica
17.
Ann Intern Med ; 118(9): 701-6, 1993 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-8460856

RESUMO

OBJECTIVE: To study the prevalence and pathogenesis of hypopituitarism following tuberculous meningitis in childhood. DESIGN: A retrospective cross-sectional study. SETTING: A university teaching hospital and a tuberculosis referral center. PATIENTS: Forty-nine patients, aged 23.4 +/- 6.0 years (mean +/- SD), who had tuberculous meningitis in childhood (age at diagnosis, 5.9 +/- 5.0 years) were studied. MEASUREMENTS: A detailed assessment of hypothalamic-pituitary function, including conventional stimulation tests and responses to four hypothalamic releasing hormones, was done. Magnetic resonance imaging of the hypothalamic-pituitary region was performed in patients with abnormal endocrine function. RESULTS: Ten patients were found to have abnormal pituitary function: Seven had growth hormone deficiency, four of whom also had gonadotropin deficiency; the other three had gonadotropin deficiency, corticotropin deficiency, and mild hyperprolactinemia, respectively; none had diabetes insipidus. Among those with growth hormone deficiency, a significant correlation (r = 0.749, P < 0.05) was found between the height standard deviation score and the age at diagnosis of tuberculous meningitis. Growth hormone, corticotropin, and gonadotropin responses to growth hormone releasing hormone, corticotropin releasing hormone, and gonadotropin releasing hormone, respectively, suggested a hypothalamic defect in five patients. Magnetic resonance imaging scans of the hypothalamic-pituitary region were abnormal in five patients. CONCLUSIONS: Hypopituitarism was documented in 20% of a small subset of patients years after recovery from tuberculous meningitis in childhood. The cause appears to be tuberculous lesions affecting the hypothalamus, pituitary stalk and, directly or indirectly, the pituitary itself. Early recognition and treatment can be beneficial.


Assuntos
Hipopituitarismo/etiologia , Tuberculose Meníngea/complicações , Adolescente , Adulto , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Hipopituitarismo/sangue , Hipopituitarismo/patologia , Hipotálamo/patologia , Lactente , Imageamento por Ressonância Magnética , Masculino , Análise Multivariada , Hormônios Adeno-Hipofisários/sangue , Estudos Retrospectivos
18.
J Gastroenterol Hepatol ; 7(5): 508-11, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1391732

RESUMO

Direct comparisons of ulcer perforation rates and trends between countries have not been made in the past. Data on hospital admissions for perforated peptic ulcer during 1 January 1979 to 31 December 1985 were collected in Hong Kong (5868 perforations) and New South Wales, Australia (1669 perforations). Age and sex specific rates per 100,000 population were calculated. In Hong Kong, annual duodenal ulcer and gastric ulcer perforation rates were 13-16 and under two per 100,000 population respectively. In New South Wales, the corresponding rates were between three and four and under two per 100,000 population, respectively. The male:female ratios for duodenal ulcer perforation were consistently about 5:1 in Hong Kong and 2:1 in New South Wales, and for gastric ulcer perforation about 2:1 and 1:1, respectively. The incidence of perforation increased with age, and there was a statistically significant rise, over time, in duodenal but not gastric ulcer perforation rates in persons aged over 60 years in New South Wales; similar trends were seen in Hong Kong. Thus duodenal ulcer perforation occurs five times more commonly in Hong Kong than in New South Wales and this is largely accountable for by the higher rates of duodenal ulcer perforation in Chinese than in Australian males. Such geographical differences can best be explained by the occurrence of multiple aetiological mechanisms in ulcer perforation. Furthermore, there appears to be an increased susceptibility and an appreciable rising trend for duodenal ulcer perforation to occur in the elderly.


Assuntos
Úlcera Péptica Perfurada/epidemiologia , Adulto , Feminino , Hong Kong/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , New South Wales/epidemiologia
19.
Cancer ; 70(1): 45-9, 1992 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-1318778

RESUMO

One hundred eighty-nine surgically resected hepatocellular carcinomas (HCC) were analyzed to study tumor encapsulation and the pathologic features that might account for the better prognosis in relation to it, and to examine the prognostic and pathobiologic significance of capsular thickness. Tumor encapsulation was found in 72 (46.8%) of the 154 cases with adequate histologic sections of the tumor-nontumor junctions. Encapsulated tumors showed a much lower incidence of direct liver invasion (P less than 0.0001), tumor microsatellites (P less than 0.0001), and venous permeation (P = 0.02) when compared with nonencapsulated ones. Significantly better disease-free and actuarial survival times were observed in patients with encapsulated tumors (medians, 9.9 and 18.3 months, respectively), compared with those with nonencapsulated ones (medians, 4.0 and 5.9 months, respectively; P = 0.0001 and 0.001, respectively). The incidence of tumor encapsulation did not increase or decrease with tumor size. Tumor encapsulation did not correlate with the presence of cirrhosis or the abundance of tumor stroma, suggesting that formation of the tumor capsule was independent of the degree of fibrosis within and outside the tumor. Among the 72 cases of encapsulated HCC, the capsular thickness ranged from 0.13 to 3.09 mm (mean +/- standard deviation = 0.87 +/- 0.59 mm), and it was unrelated to tumor size or presence of cirrhosis. Although it was apparent that a lower extensive tumor invasiveness contributed significantly to the better prognosis in encapsulated HCC, there was no correlation between capsular thickness and liver invasion, microsatellites, venous permeation, or survivals. Therefore, the thickness of tumor capsules was not helpful in prognostication.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Adulto , Idoso , Carcinoma Hepatocelular/mortalidade , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores Sexuais
20.
Am J Med ; 92(3): 265-74, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1546725

RESUMO

PURPOSE: We performed a randomized controlled trial to compare the efficacy of seven forms of maintenance treatment of duodenal ulcer, including a mealtime regimen of antacids. PATIENTS AND METHODS: We randomized 785 patients with healed duodenal ulcer to receive: (1) no treatment; (2) mealtime antacids with an acid-neutralizing capacity of 80 mmol/day; (3) an antidepressant, trimipramine 25 mg; (4) an anticholinergic, pirenzepine 50 mg; (5) cimetidine 200 mg; (6) cimetidine 400 mg; (7) ranitidine 150 mg; or (8) sucralfate 1 g twice a day. Symptomatology and side effects were assessed every 2 months and endoscopy was performed every 4 months up to 1 year. RESULTS: The patients were comparable in the majority of clinical characteristics before entry. The cumulative percentages of patients with relapse of ulcers at 12 months by life-table analysis were 61% with no treatment, 38% with mealtime antacids, 60% with trimipramine, 52% with pirenzepine, 46% with cimetidine 200 mg, 44% with cimetidine 400 mg, 30% with ranitidine 150 mg, and 40% with sucralfate. Cimetidine 400 mg, antacids, ranitidine 150 mg, and sucralfate were significantly better than no treatment and the other forms of treatment. Ranitidine was significantly better than antacids, cimetidine, and sucralfate in preventing endoscopically documented duodenal ulcer relapse by multiple comparison at 12 months, but not by life-table analysis nor when symptomatic relapses were compared. No significant difference was detected among antacids, cimetidine, and sucralfate. No major side effects occurred with the seven forms of treatment, but those receiving antacids had the highest incidence of minor adverse events (26%). CONCLUSION: This study suggests that mealtime antacids are as effective as H2-receptor antagonists and sucralfate in the maintenance treatment of duodenal ulcer disease, but have to be taken three times a day and had the highest incidence of reported minor adverse events. The relapse rate was lower with ranitidine than with cimetidine, sucralfate, and antacids, but the difference was small and may not be clinically important.


Assuntos
Antiácidos/uso terapêutico , Cimetidina/uso terapêutico , Úlcera Duodenal/tratamento farmacológico , Pirenzepina/uso terapêutico , Ranitidina/uso terapêutico , Sucralfato/uso terapêutico , Trimipramina/uso terapêutico , Adulto , Antiácidos/administração & dosagem , Antiácidos/efeitos adversos , Cimetidina/administração & dosagem , Cimetidina/efeitos adversos , Úlcera Duodenal/epidemiologia , Úlcera Duodenal/patologia , Endoscopia Gastrointestinal , Feminino , Hong Kong/epidemiologia , Hospitais Universitários , Humanos , Tábuas de Vida , Modelos Logísticos , Masculino , Pirenzepina/administração & dosagem , Pirenzepina/efeitos adversos , Ranitidina/administração & dosagem , Ranitidina/efeitos adversos , Recidiva , Fatores de Risco , Sucralfato/administração & dosagem , Sucralfato/efeitos adversos , Trimipramina/administração & dosagem , Trimipramina/efeitos adversos
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