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C H Law

Publications and source records attributed to C H Law.

10 recordsLinked to original sources
PubMed2001

Biallelic inactivation of the APC gene is associated with hepatocellular carcinoma in familial adenomatous polyposis coli.

BACKGROUND: Certain primary hepatic tumors have been associated with familial adenomatous polyposis (FAP), a condition caused by germline mutations of the adenomatous polyposis coli (APC) gene. However, a genetic association between FAP and hepatocellular carcinoma (HCC) has not been shown. This study tested the hypothesis that biallelic inactivation of the APC gene contributed to the development of HCC in a patient with FAP and a known germline mutation of the APC gene at codon 208, but no other risk factors for HCC. METHODS: Total RNA and genomic DNA were isolated from the tumor, and in vitro synthesized protein assay and DNA sequencing analysis were used to screen for a somatic mutation in the APC gene. RESULTS: A somatic one-base pair deletion at codon 568 was identified in the wild-type allele of the APC gene. CONCLUSIONS: To the authors' knowledge, this study provides the first evidence that biallelic inactivation of the APC gene may contribute to the development of HCC in patients with FAP.

Adenomatous Polyposis Coli↗
PubMed1999

The association between tamoxifen and the development of hepatocellular carcinoma: case report and literature review.

Tamoxifen has become one of the most widely used drugs in the treatment of breast cancer, and concerns about its long-term safety and efficacy are being raised. Investigations in rats have suggested an association between the administration of tamoxifen and the development of hepatocellular carcinoma. However, no studies to date have demonstrated an increased incidence of hepatocellular carcinoma in women treated with tamoxifen. In the case reported, a 56-year-old woman presented with hepatocellular tumours after 6 years of tamoxifen therapy for breast cancer. The patient had no other risk factors for the development of hepatocellular carcinoma. She underwent successful resection of the lesions, and subsequent pathological studies confirmed hepatocellular carcinoma with a trabecular growth pattern similar to the histologic pattern seen in tamoxifen-induced hepatocellular carcinoma occurring in rat models.

Animals↗
PubMed1996

Post-traumatic small-bowel stricture: a case report.

The use of lap seat belts has recently been recognized as a mechanism of blunt injury to the small bowel. Patients usually present immediately after injury and require urgent laparotomy. An unusual case of delayed small-bowel stricture after conservative management of an injury resulting from blunt trauma is reported. A 37-year-old woman involved in a high-speed motor vehicle accident was managed in hospital by observation. She had abdominal distension and pain, which gradually decreased and allowed slow introduction of a liquid diet. She was discharged from hospital but returned 6 weeks after injury with pain, abdominal distension, vomiting and obstipation. Stricture of an 8-cm segment of distal jejunum was found. Resection of the involved segment with primary anastomosis was curative.

Adult↗
PubMed1977

Risk factors for lung cancer in Singapore Chinese, a population with high female incidence rates.

The high incidence of lung cancer in Chinese females in Singapore, especially among those belonging to the Cantonese dialect group, and the relatively high rates in Chinese males have been studied by means of interviews of cases and controls. A significant dose-response effect of cigarette smoking was found for all male and female groups, but neither smoking nor any other exposure explains the high incidence of lung cancer observed in Cantonese females who exhibit high rates of adenocarcinoma appraently unrelated to smoking. In general, persons with a low consumption of green vegetables were at higher risk for lung cancer. This finding might be due to an increased susceptibility in the presence of a relative deficiency of vitamin A.

China↗
PubMed1977

Hepatitis B antigen in the liver cells in cirrhosis and hepatocellular carcinoma.

The demonstration of hepatitis B antigen in the liver cells in formalin fixed paraffin embedded tissues by Shikata's orcein staining method affords an opportunity to conduct retrospective studies on necrospy materials. Such a study in Singapore showed orcein-positive liver cells in 22 out of 52 (42.3%) and 37 out of 50 (74.0%) cases of cirrhosis of the liver and hepatocellular carcinoma respectively, while only 5 out of 113 (4.4%) 'normal' livers gave positive results. There is a significant difference in the frequency of hepatocellular carcinoma in orcein-positive and orcein-negative cirrhotic livers (28 out of 50, 10 out of 40 respectively). These results suggest a possible aetiological relationship between hepatitis B antigen and hepatocellular carcinoma.

Carcinoma, Hepatocellular↗
PubMed1977

Glomerular lesions in patients with asymptomatic persistent andorthostatic proteinuria discovered on routine medical examination.

The incidence of asymptomatic proteinuria in young healthy men entering the army service in Singapore was 0.94%; 0.56% had intermittent orthostatic proteinuria and 0.38% with persistent proteinuria. Renal biopsies from 45 cases with persistent proteinuria and 10 cases with orthostatic proteinuria were studied by light microscopy, electron microscopic and immunofluorescent antibody techniques. Three cases with orthostatic proteinuria showed a minimal lesion ('Nil'), and 7 a minimal lesion with increased centrilobular mesangial matrix and mild focal and segmental mesangial hypercellularity. Focal and segmental capillary loop changes were seen in two cases. No immunoglobulin deposits were found in orthostatic proteinuria. A raised anti-streptolysin O titer was found in 3 cases. 13.3% of cases with persistent proteinuria showed a minimal lesion ('Nil'); 66.6% a minimal lesion with increased centrilobular mesangial matrix and mild focal and segmental mesangial hypercellularity: Focal global sclerosis, focal segmental sclerosing glomerulonephritis and diffuse proliferative GN (mesangial hypercellularity) were each found in 6.7% of patients in this group. Focal and segmental changes in capillary loops were found in 30% of cases. Changes in visceral epithelium such as the appearance of cytoplasmic swelling, vesicles and dense aggregates, and areas of focal foot process fusion were common findings. Mesangial deposits of IgA were found in 34.3%, with an IgA-IgG-beta1C globulin combination in 28.6% of cases. IgM-beta1C globulin was present in 5.7% of cases with persistent proteinuria. Early complement components, C1q and C4, and IgA secretory piece were absent. A raised antistreptolysin O titer was found in 25% of cases. The changes inthe glomeruli may represent the end or healing stages of an early bout of glomerulonephritis. Changed hemodynamic responses on assuming an upright position may play a role in the loss of protein across the glomerular basement membrane in patients with orthostatic proteinuria.

Adolescent↗
PubMed1976

Incidence rates of specific histological types of lung cancer in Singapore Chinese dialect groups, and their aetiological significance.

Significant differences in the incidence levels of lung cancer have been observed among major Chinese dialect groups or communities (Kokkien, Teochew and Cantonese) in Singapore. Among males, the incidence rate is highest in the Hokkiens (age-standardized incidence rate per 100,000 persons per year in Hokkien 67.8, Teochew 55.3, Cantonese 54.0) and among females, it is highest in the Cantonese (Hokkien 12.4, Teochew 12.8, Cantonese 27.2). The present investigation was undertaken to determine the incidence rates of each of the main histological types of lung cancer in the Chinese population and to determine whether there are any correlations between histological patterns and the dialect group differentials that may be of aetiological significance. During the period 1968-1972, a total of 1,747 cases of lung cancer (1,285 males and 462 females) were reported to the Singapore Cancer Registry. It proved possible to type the neoplasms histologically in 476 males (37.0%) and 154 females (33.3%). Age-standardized rates by histological type were computed on the assumption that those histologically typed were a representative sample of all lung cancers. This study shows that Hokkien males have a significantly higher incidence rate of epidermoid carcinoma than the other dialect groups (Hokkien 36.1, Teochew 21.1, Cantonese 17.3). The Cantonese females have significantly higher incidence rates of both epidermoid carcinoma (Hokkien 3.7, Teochew 2.3, Cantonese 5.9) and adenocarcinoma (Hokkien 4.6, Teochew 3.6, Cantonese 11.9). Various sources of bias in studied of this type were examined; it is concluded that the differences in the histologic-specific incidence rates of lung cancer among the various Chinese dialect groups in Singapore are real and not artefactual. The significance of these findings in relation to possible aetiological factors is discussed.

Adenocarcinoma↗