Search PubMed⌕ Search

Biomedical subjects

S C Peh

Publications and source records attributed to S C Peh.

At least 37 records · Page 2Linked to original sources
PubMed1999

The pattern of lymphoma in east Malaysian patients as experienced in the University Hospital, Kuala Lumpur.

Lymphoma is a highly heterogeneous group of malignant disease. This study aimed to elucidate the pattern of lymphoma in the East Malaysian patient population. 107 cases of confirmed lymphomas from East Malaysian biopsy material were retrieved from the files of the Department of Pathology, University of Malaya, in the 3-year period between 1981 to 1983. With the use of a panel of lymphoid antibodies, the disease was sub-classified using the Rye classification for Hodgkin's lymphoma (HL) and the REAL classification for non-Hodgkin's lymphoma (NHL). All of the cases were tested for the presence of the Epstein-Barr virus by EBER-ISH. There were 11 (10.3%) HL, 80 (74.7%) B-NHL and 16 (15%) T-NHL. The HL:NHL ratio was 1:9. The most common tumour in children was Burkitt's lymphoma 7/13 (53.8%). In the adult group, there were 72/94 (76.6%) B-NHL ¿diffuse large cell type 51 (of which 2 were CD30+), Burkitt's lymphoma 8, follicular lymphoma 5, low grade MALT 2, mantle cell type 1 and not otherwise specified due to poor morphology 5¿, 13/94 (13.8%) T-NHL and 9/94 (9.6%) HL. Of the 9 adult HL, the most common subtype was nodular sclerosis (6, 66.7%). The EBER positive rate in classical HL, T-NHL, BL and B-NHL were 33.3%, 56.3%, 60.0% and 3.1% respectively. In conclusion, the spectrum of lymphoma seen in East Malaysia was rather similar to West Malaysia except for the very low prevalence of peripheral T-cell lymphoma (PTCL) in Sarawak (3.3%).

Adolescent↗
PubMed1999

Pattern of lymph node pathology in a private pathology laboratory.

Lymph node excision biopsy is commonly carried out for the investigation of lymphadenopathy. The objective of this study is to elucidate the pattern of nodal pathology seen in a private pathology practice. A total of 137 nodal biopsies for primary investigation of nodal enlargement were retrieved from the files in a private diagnostic pathology laboratory in the year 1997. Lymph nodes excised for cancer staging were excluded from this study. The histology was reviewed based on H&E stained sections, and with additional histochemical and immunoperoxidase stains when deemed necessary. Cases of malignant lymphomas were sub-classified with the aid of further immunophenotyping using a panel of monoclonal and polyclonal lymphoid antibodies. One case was excluded from this study due to inadequate tissue for further assessment. There were 58 males and 78 females, giving a ratio of 1:1.3 in the remaining 136 cases. They consisted of 13 Malays (M), 108 Chinese (C), 14 Indians (I) and 1 other ethnic group (O). The ratio of M:C:I:O was 1:8.3:1.1:0.1. The majority of the cases were in the age range of 20 to 50 years. The pathology consisted of 17 (12.5%) malignant lymphomas [6 Hodgkin's lymphoma, 11 non-Hodgkin's lymphoma], 35 (25.7%) metastatic carcinomas, 45 (33.1%) reactive hyperplasia, 19 (13.9%) tuberculosis, 11 (8.2%) Kikuchi's disease and 9 (6.6%) others (Castleman's disease 2, cat scratch disease 2, Kimura's disease 1, sarcoidosis 1, non-specific lymphadenitis 3). All categories of nodal disease showed approximately similar ratio of ethnic and gender distribution as above, except for Kikuchi's disease, for which 100% of the patients were female. The most common site of biopsy was from the head and neck region, particularly the cervical group of nodes. The most common nodal pathology seen in the private laboratory was reactive hyperplasia, followed by metastatic carcinoma. Malignant lymphoma constituted only 12.5% of the cases.

Adolescent↗
PubMed1997

Epstein-Barr virus (EBV) and Hodgkin's disease in a multi-ethnic population in Malaysia.

The Epstein-Barr virus (EBV) has been implicated as a contributing factor in the development of Hodgkin's disease. Western cases of Hodgkin's disease have shown the presence of EBV in Hodgkin and Reed-Sternberg cells in approximately 50%. We studied a total of 100 consecutive cases of Hodgkin's disease from Malaysia, with the aim to elucidate its association with EBV in a multi-ethnic Asian population. Of 34 patients (34%) less than 15 years of age (childhood), 25 had classical Hodgkin's disease (eight nodular sclerosis, 16 mixed cellularity, one lymphocyte depleted) and nine had lymphocyte predominance Hodgkin's disease. Of the 66 from patients aged 15 years and above, 33 had nodular sclerosis, 24 mixed cellularity, two lymphocyte depleted, one unclassifiable and six lymphocyte predominance Hodgkin's disease. The ethnic distribution of classical Hodgkin's disease was: Malay 23, Chinese 32 and Indian 30 (Malay:Chinese:Indian = 1:1.4:1.3), and the ethnic distribution in the 15 cases of lymphocyte predominance Hodgkin's disease was: Malay four, Chinese 10 and Indian one. Taking into account the ethnic distribution of the general population and of hospital admissions, there appears to be a significant predilection of classical Hodgkin's disease cases in ethnic Indian compared to non-Indian patients (chi-squared test, 0.025 > P > 0.01). Eighty-one cases were tested for the presence of EBV by in situ hybridization for EBV encoded RNA, and 57 cases by immunostaining for EBV latent membrane protein 1. In the younger age group, all except one of the 15 cases (nine mixed cellularity, six nodular sclerosis) showed the presence of EBV (93%). In the older age group, EBV was detected (52%) in the following proportion: 6/27 nodular sclerosis, 19/22 mixed cellularity, 1/2 lymphocyte depleted, 1/1 unclassifiable. None of the 14 cases of lymphocyte predominance Hodgkin's disease showed the presence of EBV in the Hodgkin and Reed-Sternberg cells. The findings suggest a strong association of EBV with Hodgkin's disease in Malaysians (41/67, 61%), in particular childhood cases (93%). In adults, the association with EBV is significantly higher in the mixed cellularity subtype (86%) compared with the nodular sclerosis subtype (22%).

Adolescent↗
PubMed1997

Does Helicobacter pylori infection affect gastric emptying in patients with functional dyspepsia?

The objectives of the study were first, to determine if gastric emptying was altered in patients with functional dyspepsia with and without Helicobacter pylori infection compared with normal healthy volunteers; and second, to determine if there were further alterations in gastric emptying when the infection was eradicated. Gastric emptying was measured using a 99mtechnetium radiolabelled solid meal and gastric emptying time was measured as t1/2, viz. time taken for half the radiolabelled meal to be emptied from the stomach. The mean gastric emptying time for H. pylori-positive patients (n=20) was 56.4+/-24.8 min; H. pylori-negative patients (n=19) 67.8+/-31.8 min; and normal controls (n=20) 58.8+/-18.8min. No significant difference was obtained between the groups (ANOVA; P=0.348). Thirteen of 18 H. pylori-positive patients successfully eradicated the infection following treatment with omeprazole 40 mg o.m. and amoxycillin 500 mg t.d.s. for 2 weeks. The mean difference in the gastric emptying time before and after H. pylori eradication was 23.9+/-13.2 min (P= 0.556). There was no significant difference in the frequency of specific dyspeptic symptoms as well as the overall mean symptom score between the H. pylori-positive and -negative patients. Gastric emptying was not different between patients with functional dyspepsia and normal controls. Helicobacter pylori infection does not appear to affect gastric emptying in patients with functional dyspepsia.

Adolescent↗
PubMed1997

The pattern of Ki-67 and bcl-2 expression in lymphoid malignancies.

The International Working Formulation divides non-Hodgkin's lymphoma (NHL) into three grades: low, intermediate and high. This grading system implies rate of tumour growth and hence prognosis. Ki-67 antigen is a proliferation-related nuclear antigen and bcl-2 oncogene product is known to inhibit apoptosis. This study aimed to determine the pattern of expression of Ki-67 antigen and bcl-2 oncoprotein in various grades of NHL. Paraffin-embedded tissues from 42 cases of NHL (7 low, 15 intermediate, 20 high grade) were retrieved from the files of the Department of Pathology, University of Malaya. Ki-67 antigen and bcl-2 oncoprotein were detected using immunohistochemistry. The percentage of positively stained neoplastic cells was determined by semi-quantitative estimation and given scores ranging from 0 to 6. Partition chi square test demonstrated the association of Ki-67 antigen expression and histological grade (p = 0.007). There was no significant difference in Ki-67 antigen expression between intermediate and high grade malignant lymphomas (p = 0.28), whereas significant difference was demonstrated between low and intermediate/high grade tumours (p = 0.003). Bcl-2 oncoprotein expression in the neoplastic cells varied widely within the three histological grades. Statistical analysis showed no association between the expression of bcl-2 oncoprotein and histological grade (p = 0.25). Ki-67 immunostaining is therefore a useful adjunct to histological grading of NHL.

Humans↗
PubMed1996

Reinfection and duodenal ulcer relapse in south-east Asian patients following successful Helicobacter pylori eradication: results of a 2-year follow-up.

OBJECTIVES: To determine the reinfection rate of Helicobacter pylori and duodenal ulcer relapse rate in a group of patients followed up long term. DESIGN: Prospective study. PATIENTS AND METHODS: Patients were followed up endoscopically at 3, 6, 12 and 24 months after successful H. pylori eradication and duodenal ulcer healing. H. pylori status was determined by culture, rapid urease test, Gram's stain of a fresh tissue smear and histological examination of antral biopsies and rapid urease test and histological examination of corpus biopsies. MAIN OUTCOME MEASURES: Duodenal ulcer healing, H. pylori reinfection. RESULTS: Thirty-eight patients with duodenal ulcer disease (35 active, 3 healed) had successfully eradicated H. pylori following treatment with omeprazole/amoxycillin (n = 11), omeprazole/amoxycillin/metronidazole (n = 16) and colloidal bismuth subcitrate/ amoxycillin/metronidazole (n = 11). All patients with active duodenal ulcer had healed ulcers at the end of therapy. Thirty-five of 38 patients were seen according to schedule up to 2 years; two patients were seen up to 12 months and one up to 6 months only. Reinfection with H. pylori was not recorded in any of our patients. Shallow duodenal ulcers were noted in three patients at 1-year follow-up, two of whom admitted to taking non-steroidal anti-inflammatory drugs (NSAIDs); H. pylori status was negative in all three. Subsequent follow-up revealed spontaneous healing of the ulcers in all three patients. At 2 years, one patient whose H. pylori status was negative had recurrence of duodenal ulcer. All of the three patients who defaulted subsequent to follow-up were negative for H. pylori and had healed ulcers on follow-up endoscopy at 6 and 12 months. CONCLUSION: Reinfection rate with H. pylori was zero in a group of South-East Asian patients who had successfully eradicated the infection. Duodenal ulcer relapse was also low (2.9%) in this group of patients at 2 years.

Amoxicillin↗
PubMed1996

Helicobacter pylori eradication with short-term therapy leads to duodenal ulcer healing without the need for continued acid suppression therapy.

OBJECTIVE: To determine whether duodenal ulcers continue to heal following successful Helicobacter pylori eradication with short-term eradication therapy without further acid suppression therapy. METHODS: Patients with endoscopically proven duodenal ulcers who were H. pylori positive were randomized to receive omeprazole 40 mg each morning and clarithromycin 500 mg three times daily or famotidine 40 mg twice daily and clarithromycin 500 mg three times daily for 2 weeks. No acid-suppressing agents nor ulcerhealing drugs such as bismuth compounds or sucralfate were prescribed after that. Patients were re-examined endoscopically at week 2 at the end of treatment, and at week 6, 4 weeks after the completion of treatment. RESULTS: Thirty of 44 (68.2%) patients from both treatment arms, in whom the bacteria were subsequently noted to have been eradicated, had healed ulcers at week 2; at Week 6, 42 of 44 (95.5%) were noted to have healed ulcers without further acid-suppressing or ulcer-healing treatment. CONCLUSION: Although a short-term acid-suppressing treatment is insufficient to heal ulcers, where an important putative factor such as H. pylori is eliminated, the ulcer healing process continues without further need for acid-suppressing or ulcer-healing agents.

Adult↗
PubMed1995

Epstein-Barr virus (EBV) in Malaysian upper-aerodigestive-tract lymphoma: incidence and sub-type.

Epstein-Barr virus (EBV) type B, a less potent transformer of B lymphocytes than type A, has rarely been detected in EBV-associated neoplasms except in AIDS-related lymphomas, in which about 50% of the cases contained this sub-type. In this study we analyzed the association of EBV and the distribution of virus sub-types in Asian non-Hodgkin's lymphoma (NHL) of the upper aerodigestive tract. We studied archival material of 29 NHL cases from Malaysia. B- and T-cell associated antigens were demonstrated by immunohistochemistry, and EBV early RNA EBER-1 was demonstrated using the RNA in situ hybridization technique. EBV was detected in the majority of tumour cells in 11/13 T-NHL but in only 1/16 B-NHL. EBV was sub-typed by single-step polymerase chain reaction of the EBNA-2 gene. This was successful in 9/10 cases of EBER-1-positive tumours and all contained type-A virus only. Our results showed a preponderance of T-cell lymphoma of the upper aerodigestive tract in the ethnic Chinese group of Malaysian patients, and EBV was strongly associated with T-NHL but not with B-NHL. Our results suggest that type-A EBV is the prevalent sub-type in Asian NHL of the upper aerodigestive tract, similarly to findings in Asian nasopharyngeal carcinoma.

Adult↗
PubMed1995

Prolonged treatment with omeprazole does not improve the eradication rate of Helicobacter pylori infection--a short report [corrected].

Omeprazole has been shown to have a suppressive effect on Helicobacter pylori. The aim of this study was to determine if prolonged treatment with omeprazole would result in a higher eradication rate than short course treatment. Twenty patients with endoscopy proven duodenal ulcers and unequivocal evidence of Helicobacter pylori (HP) infection based on culture, histology, urease test and Gram's stain of a fresh tissue smear were treated with omeprazole 40 mg om for 2-4 weeks. Following ulcer healing, patients received either maintenance omeprazole 20 mg om or placebo for up to one year. All 20 patients had healed ulcers following a 2-4 week course of omeprazole 40 mg om.. All were negative for HP at the end of treatment. Thirteen patients received short course therapy with omeprazole only, followed by placebo. On follow-up endoscopy at 3 months, only one of 13 (7.7%) had eradicated the bacteria. Seven patients received maintenance treatment with omeprazole 20mg om for one year. Following completion of treatment, patients were followed up at 1, 3 and 6 months. Only one of 7 (14.3%) patients had eradicated the infection on long term follow-up. The eradication rates of HP with both short and long course omeprazole monotherapy were low.

Adult↗
PubMed1995

14C-urea breath test: a useful non-invasive test in the diagnosis of Helicobacter pylori infection.

Sixty-three breath samples were collected from patients who underwent a 14C-urea breath test. Following ingestion of a radiolabelled 14C-labelled urea solution, breath samples containing 14C-labelled carbon dioxide were trapped in a solution containing hyamine hydroxide. Samples were then counted in a liquid scintillation counter. Breath samples were collected at 2, 15, 20, 25 and 30 minutes following ingestion of the urea solution. The presence or absence of Helicobacter pylori (HP) infection was determined on the basis of endoscopic biopsy tests which included culture, histological examination, rapid urease test and a gram stain of a fresh tissue smear. Thirty-two HP positive and 31 HP negative samples were collected. The mean counts at 15, 20, 12 and 30 minutes time points were: 4413, 4458, 4109 and 3795 dpm respectively for the positive samples and 1275, 877, 690 and 565 dpm respectively for the negative samples. Based on a cutoff value (mean of the negative samples + 3 standard deviations) for every time point, HP positive and negative samples could be clearly differentiated giving a sensitivity and specificity of 100%. The 14C-urea breath test is a reliable and convenient diagnostic test for H. pylori.

Breath Tests↗
PubMed1994

Identification of potential hot spots in the carboxy-terminal part of the Epstein-Barr virus (EBV) BNLF-1 gene in both malignant and benign EBV-associated diseases: high frequency of a 30-bp deletion in Malaysian and Danish peripheral T-cell lymphomas.

In this study, we have sequenced the C-terminal part of the Epstein-Barr virus (EBV)-BNLF-1 gene encoding for the latent membrane protein-1 from tissues of EBV-positive Danish Hodgkin's disease (HD) and of Danish and Malaysian peripheral T-cell lymphomas (PTLs) and from tonsils of Danish infectious mononucleosis (IM). Our study showed that some of the 7 single-base mutations and the 30-bp deletion previously detected between codons of amino acid 322 and 366 in the BNLF-1 gene of the nasopharyngeal carcinoma cell line CAO were present in all Malaysian PTLs and in 60% of the Danish PTLs. In HD and the IM cases, the mutations were present in about 30%. The 30-bp deletion and the single base mutations occurred independently, and mutations were detectable in the majority of EBV type B-positive cases. These findings suggest that the 30-bp deletion and the 7 single-base mutations in the C-terminal part of the CAO-BNLF-1 gene do not characterize a new EBV type A substrain. Rather, some of the positions of single base mutations and the 30-bp deletion are hot spots that may have mutated independently through the evolution of EBV strains.

Amino Acid Sequence↗
PubMed1994

The rapid urease test in the diagnosis of Helicobacter pylori infection.

With the increasing recognition of the importance of H. pylori in gastrointestinal disease, there is a need for a reliable, efficient and yet inexpensive diagnostic test. The performance of the rapid urease test (RUT) as an endoscopy suite diagnostic test was compared to the established methods of culture, histology and Gram stain of tissue smear, in 274 gastric biopsy samples. Histology had the highest sensitivity of 99.3% followed by the RUT (96.6%). Culture and Gram stain of tissue smear had 100% specificity, while the rapid urease test had 99.2% specificity. The RUT had a positive predictive value of 99.3% and a negative predictive value of 96.2%. The RUT is an inexpensive, rapid and reliable diagnostic test of H. pylori infection.

Biopsy↗
PubMed1994

Omeprazole 40 mg o.m. combined with amoxycillin alone or with amoxycillin and metronidazole in the eradication of Helicobacter pylori.

OBJECTIVES: Our objectives were to determine the effect of dual therapy with omeprazole and amoxicillin and of triple therapy with omeprazole, amoxicillin, and metronidazole in the eradication of Helicobacter pylori (HP) and to study the long-term results of eradication in these patients. METHODS: A prospective, randomized, controlled trial was performed. Patients who were recruited had unequivocal evidence of HP infection based on culture, histology, rapid urease test, and Gram's stain of a tissue smear. Eradication was defined as the absence of bacteria in all tests performed on both corpus and antral biopsies. RESULTS: The infection was eradicated in 15 of 19 (78.9%) patients randomized to receive dual therapy and in 19 of 22 (86.4%) patients who received triple therapy. We followed the course of 30 patients in whom HP had been eradicated for a prolonged term (up to 12 months). All remained clear of HP. Twenty-five of 28 patients (89.3%) with duodenal ulcers in whom HP was successfully eradicated remained healed at 12 months. Fewer side effects were reported among patients who received the dual therapy. CONCLUSIONS: Combination therapy with omeprazole and amoxicillin with or without metronidazole is effective in the eradication of HP. In particular, the dual therapy regimen with amoxicillin is not only effective but is also well tolerated by patients.

Adult↗
PubMed1992

HTLV-I antibody study in normal individuals and unselected hospital patients in Malaysia.

A serological investigation for human T cell leukemia virus I (HTLV-I) infection was carried out at the University Hospital, Kuala Lumpur. A total of 626 sera from a non-patient population and 1,038 sera from unselected in-patients were screened for HTLV-I antibodies using an enzyme-linked immunosorbent assay (ELISA). 27/1664 (1.6%) were found to be reactive. However, on Western blotting, only 2 sera were confirmed positive, both showing reactions for the major core (p19 and p24) and the envelope (gp46) proteins. Both of the serum samples were from unselected hospital patients. Most of the remaining sera which were reactive on screening showed indeterminate results on Western blotting. These were further tested by radioimmunoprecipitation assay (RIPA) and none of these sera gave a positive reaction. Therefore, only 2/1038 (0.19%) unselected patients could be confirmed to have antibodies to HTLV-I. None of the normal individuals screened showed a positive Western blot result. Our data indicate that HTLV-I infection is present in our population, but at a low prevalence rate.

Adult↗
PubMed1991

Chronic pyelonephritis: the significance of renal renin and the vascular changes in the human kidney.

Hypertension complicates chronic pyelonephritis. Since arterial narrowing is common in the damaged kidney, activation of the renin-angiotensin system due to renal ischaemia has been suggested as a pathogenetic mechanism. We used an antiserum to human renin and an immunoperoxidase technique to study the anatomy of renin-containing cells (RCC) in 18 kidneys removed for pyeloneophritis. We independently assessed the degree of arterial narrowing and correlated these variables with the clinical findings. There was histological evidence of hyperplasia of RCC in 5 of the 6 hypertensive patients and in 7 of the 12 non-hypertensive cases. There was no difference in the apparent number or distribution of RCC between the hypertensive and the non-hypertensive cases. Also, the degree of arterial narrowing did not correlate with either the hyperplasia of RCC or the blood pressure of the patients. Our results do not support the hypothesis that narrowing of the intrarenal arteries is important in the pathogenesis of hypertension in pyelonephritis. In our cases, the renal veins were more severely damaged than the arteries and their lumina were often obliterated by organized thrombus. We suggest that such widespread obliteration of the renal venous tree could impair blood flow and contribute to the tissue damage in the pyelonephritic kidney.

Adolescent↗
PubMed1991

Helicobacter pylori infection and non-ulcer dyspepsia: the effect of treatment with colloidal bismuth subcitrate.

A study was undertaken to determine the role of Helicobacter pylori in non-ulcer dyspepsia (NUD) and to determine the efficacy of colloidal bismuth subcitrate (CBS) in the treatment of NUD. Seventy-one patients were randomly allocated (double blind) to CBS or placebo, two tablets twice daily for 4 weeks. The severity of dyspepsia was scored and endoscopies performed before and after treatment, and antral biopsy specimens were taken for bacteriologic and histologic examination. Forty patients had H. pylori infection, and all had changes of chronic active gastritis. H. pylori was cleared from 17 to 21 patients (81%) treated with CBS, whereas none of the 19 patients treated with placebo cleared the bacteria. Improvement in histology was noted in 15 of 21 patients (71.4%) treated with CBS, whereas no improvement was noted in any of the placebo controls. Thirty-one patients were negative for H. pylori. All had either normal gastric histology or minor degrees of inflammation. Seventeen of these patients received CBS, and 14 received placebo. All groups reported improvement in the symptom score; however, the H. pylori-positive, CBS-treated group recorded a significantly higher improvement than the other groups (p less than 0.001). Relapse of H. pylori infection after initial clearance of the bacteria was high. Twelve of 16 patients evaluated relapsed 1 month after withdrawal of CBS.

Adult↗