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Biomedical subjects

P Kuperan

Publications and source records attributed to P Kuperan.

At least 19 recordsLinked to original sources
PubMed2000

Morbidity after a bite from a 'non-venomous' pet snake.

We report the first recorded case of morbidity from the bite of a red-neck keelback snake (Rhabdophis subminiatus) from South East Asia. This is a species of the Colubrid family which originated from South East Asia. Severe envenomation from this snake was reported as poisonous in the West as far back as 1978 but it is still being classified as non-venomous. This classification led our patient to keep this 'harmless' snake as a pet. We recommend that this snake be reclassified as 'venomous' or at least warnings be issued to the public not to keep it as a pet.

Adult↗
PubMed1999

Identification and characterization of two missense mutations causing factor XIIIA deficiency.

In this study, two amino acid substitutions, Arg260His and Val414Phe, have been identified in the factor XIIIA subunits of factor XIII deficient patients of Syrian and Indian descent, respectively. To confirm the deleterious effects of these substitutions, both variant sequences have been engineered into cDNA clones and the mutant enzymes expressed in yeast. Determination of the transglutaminase activity and immuno detection of the mutant enzymes together with mRNA hybridization revealed that the mutations dramatically reduce both the catalytic activity and the level of enzyme expressed in yeast. The mutations Arg260His and Val414Phe occur within the 'core' domain of the enzyme. Computer modelling of the mutant enzymes reveals that the substitution of the Arg260 by His results in the loss of a conserved electrostatic interaction whereas the effect of the Val414Phe substitution is a consequence of the large increase in side-chain volume. Although both mutations do not effect the active site directly, they are predicted to reduce the stability of the enzyme. The effects of these two amino acid substitutions on enzyme expression and three-dimensional structure strongly confirm that residues which are located outside of the active site can have a significant effect on protein stability and function.

Adult↗
PubMed1998

Cardiovascular risk factors in non-insulin-dependent diabetics compared to non-diabetic controls: a population-based survey among Asians in Singapore.

Cardiovascular risk factors were compared between 126 people with non-insulin-dependent diabetes mellitus (NIDDM) and 530 non-diabetics (controls), in a random sample of people (Chinese, Malays, and Asian Indians) aged 40-69 years from the general population of Singapore. Data were adjusted for age and ethnicity. For both genders, people with NIDDM had higher mean body mass indices, waist-hip ratios and abdominal diameters. They also had a higher prevalence of hypertension, higher mean levels of fasting serum triglyceride, slightly lower mean levels of serum high-density-lipoprotein cholesterol, and higher mean levels of plasma plasminogen activator inhibitor-1 and tissue plasminogen activator (antigen). These factors are components of syndrome X (metabolic syndrome) and increase the risk of atherosclerosis and thrombosis. In contrast, there were no important differences for cigarette smoking, serum total and low-density-lipoprotein cholesterol, serum apolipoproteins A1 and B, plasma factor VIIc and plasma prothrombin fragment 1 + 2. Females with NIDDM, but not males, had a higher mean serum fibrinogen level than non-diabetics, which could explain why NIDDM has a greater cardiovascular effect in females than males. Serum lipoprotein(a) concentrations were lower in people with NIDDM. Mean levels of serum ferritin, a pro-oxidant, were higher in people with NIDDM than controls, but there were no important differences for plasma vitamins A, C and E, and serum selenium, which are anti-oxidants.

Arteriosclerosis↗
PubMed1998

Cardiovascular risk factors in relation to cigarette smoking: a population-based survey among Asians in Singapore.

To investigate how cigarette smoking increases the risk of cardiovascular disease, risk factors were compared between 166 cigarette smokers and 312 non-smokers, in a random sample of males (Chinese, Malays and Asian Indians) aged 30-69 years from the general population of Singapore. There was adjusted for age and ethnic group. The prevalence of hypertension was lower in cigarette smokers (15.2%) than non-smokers (21.9%), with the difference reduced by adjustment for body mass index (BMI). Smokers had: lower mean serum HDL-cholesterol (0.76 versus 0.81 mmol/l) and higher mean serum fasting triglyceride (1.92 versus 1.71 mmol/l), which will increase atherosclerosis; higher mean plasma fibrinogen (2.75 versus 2.67 g/l) and plasminogen activator inhibitor 1 [PAI-1] (24.9 versus 22.2 ng/ml), which will increase thrombosis; and lower mean plasma vitamin C (4.4 versus 6.4 mg/l) and serum selenium (118 versus 123 microg/l), which may increase atherosclerosis. Adjustment for BMI slightly increased the differences for HDL-cholesterol, fasting triglyceride, fibrinogen and PAI-1, indicating that less generalised obesity among smokers reduces their increased cardiovascular disease risk. Smoking was not found to be related to: diabetes mellitus; serum total cholesterol, LDL-cholesterol, apolipoproteins A1 and B and lipoprotein(a); plasma factor VIIc and prothrombin fragment 1 + 2; and plasma vitamins A and E and serum ferritin. There was no evidence of increased insulin resistance in smokers, as measured by mean fasting serum insulin.

Adult↗
PubMed1998

Structuring a safer donor-replacement program.

BACKGROUND: Replacement donors are more likely than volunteer donors to have positive or abnormal tests for transfusion-transmissible disease. In an effort to increase the donor pool, workers sought to identify a safer replacement-donor subgroup that may be acceptable for routine donations. STUDY DESIGN AND METHODS: In a retrospective review and cohort study, the replacement-donor effect was separated from the new-donor effect. The relative effect the replacement donor has on the risk of transfusion-transmissible diseases, donor retention, and frequency of returning donations was then quantified by comparison against the effect of repeat volunteer donors. RESULTS: The replacement donor had 3.1 times the risk and 0.72 times the donor retention rate and made 0.81 times as many returning donations as the repeat volunteer donor. The figures for the new-donor effect were similar. The two risks were additive, making a new replacement donor particularly hazardous. If replacement donations only from repeat replacement donors were considered, the donor risk and the number of donations per returning donor were made comparable to those for the general (combined) volunteer donor. CONCLUSION: The negative effect of the replacement donor is similar in magnitude to that of the new volunteer donor. A replacement-donation program targeting repeat replacement donors has an acceptable risk profile and may be a valuable adjunct to the collection of blood from general volunteer donors.

Blood Donors↗
PubMed1998

A comparison between intravenous iron polymaltose complex (Ferrum Hausmann) and oral ferrous fumarate in the treatment of iron deficiency anaemia in pregnancy.

Anaemia is the most common medical disorder in pregnancy with iron deficiency anaemia accounting for the majority of cases. Over 90% of the iron deficiency anaemia is due to red cell iron deficiency associated with depleted iron stores and deficient intake. The two main modalities of treating iron deficiency anaemia are oral or parenteral iron. Ferrous Hausmann (iron dextrin) is the latest iron preparation which can be used for intravenous parenteral administration as a total dose infusion. This study compares the efficacy of Ferrum Hausmann with oral ferrous fumarate therapy in the treatment of iron deficiency anaemia in pregnancy. Our study shows that treatment with intravenous Ferrum Hausmann (iron dextrin) resulted in a significantly better level and rate of increase of haemoglobin (p<0.001). Serum ferritin, which is the best indicator of iron stores, was significantly higher (p<0.001) in the intravenous group. Other indices of iron status such as serum iron, serum transferrin and zinc protoporphyrin also showed a significant improvement in the intravenous group compared to those given oral iron. The results suggest that intravenous iron as a total dose infusion is able to replenish iron stores more efficiently, completely and at a faster rate than oral iron therapy, thus providing the fuel for stimulation of full erythopoiesis compared to oral iron. There were also no reports of any adverse reactions with intravenous iron dextrin, whereas there were a considerable proportion of women on oral iron therapy who reported side effects. In conclusion, intravenous iron therapy with Ferrous Hausmann (iron dextrin) is a suitable, effective and safe alternative to oral iron therapy in the treatment of iron deficiency anaemia in pregnancy.

Administration, Oral↗
PubMed1997

Central obesity, insulin resistance, syndrome X, lipoprotein(a), and cardiovascular risk in Indians, Malays, and Chinese in Singapore.

STUDY OBJECTIVE: To examine the hypothesis that the higher rates of coronary heart disease (CHD) in Indians (South Asians) compared with Malays and Chinese is at least partly explained by central obesity, insulin resistance, and syndrome X (including possible components). DESIGN: Cross sectional study of the general population. SETTING: Singapore. PARTICIPANTS: Random sample of 961 men and women (Indians, Malays, and Chinese) aged 30 to 69 years. MAIN RESULTS: Fasting serum insulin concentration was correlated directly and strongly with body mass index (BMI), waist-hip ratio (WHR), and abdominal diameter. The fasting insulin concentration was correlated inversely with HDL cholesterol and directly with the fasting triglyceride concentration, blood pressures, plasminogen activator inhibitor 1 (PAI-1), and tissue plasminogen activator (tPA), but it was not correlated with LDL cholesterol, apolipoproteins B and A1, lipoprotein(a), (Lp(a)), fibrinogen, factor VIIc, or prothrombin fragment (F)1 + 2. This indicates that the former but not the latter are part of syndrome X. While Malays had the highest BMI, Indians had a higher WHR (men 0.93 and women 0.84) than Malays (men 0.91 and women 0.82) and Chinese (men 0.91 and women 0.82). In addition, Indians had higher fasting insulin values and more glucose intolerance than Malays and Chinese. Indians had lower HDL cholesterol, and higher PAI-1, tPA, and Lp(a), but not higher LDL cholesterol, fasting triglyceride, blood pressures, fibrinogen, factor VIIc, or prothrombin F1 + 2. CONCLUSIONS: Indians are more prone than Malays or Chinese to central obesity with insulin resistance and glucose intolerance and there are no apparent environmental reasons for this in Singapore. As a consequence, Indians develop some but not all of the features of syndrome X. They also have higher Lp(a) values. All this puts Indians at increased risk of atherosclerosis and thrombosis and must be at least part of the explanation for their higher rates of CHD.

Adult↗
PubMed1997

Splenic lymphoma with villus lymphocytes--an uncommon cause for lymphocytosis.

We describe the clinical and laboratory features of four patients who presented with mild to moderate lymphocytosis but with no peripheral lymphadenopathy. These patients in the past, would have been classified as chronic lymphocytic leukaemia (CLL). However, it is now realised that chronic lymphoproliferative disorders are very heterogeneous and the clinical and laboratory features of our patients would support a diagnosis of splenic lymphoma with villus lymphocytes (SLVL) with characteristic morphological features. SLVL usually runs a benign clinical course but symptoms related a benign clinical course but symptoms related to splenomegaly or hypersplenism may be a problem. Splenectomy is considered the treatment of choice in these patients. Two of our patients had splenectomy and the other two patients are on regular follow-up without any specific treatment. It is therefore important to recognise this uncommon condition and also to differentiate it from CLL.

Diagnosis, Differential↗
PubMed1996

The incidence of viremia and the heterogeneity of hepatitis C virus genotypes among blood donors, hemophiliacs and patients with chronic liver disease.

Hepatitis C Virus (HCV) is the major cause of parentally transmitted non-A, non-B hepatitis. We studied the incidence of HCV Viremia in blood donors, hemophiliacs and patients with chronic liver disease who are positive for antibodies to HCV, and then correlated the HCV genotypes among the three groups. 23 blood donors, 10 hemophiliacs and 97 patients with chronic liver disease were found to be positive for anti-HCV during this study period from June 1993 to December 1993. Only 3 (13%) blood donors, 6 (60%) hemophiliacs and 71 (73%) patients with chronic liver disease were found to be viremic when tested for HCV RNA by reverse transcriptase-polymerase chain reaction (RT-PCR). The low incidence of viremia among blood donors may be due to any one of the following three reasons. 1, the level of viremia was below the level of detection. 2, the viremia was intermittent with persistent infection. 3, the majority of cases represented resolved infection. The HCV genotypes were heterogeneous among the three groups. All the blood donors with viremia and 35 (50%) of patients with chronic liver disease, belonged to type II (1b). However only one (17%) of the hemophiliacs belonged to type II (1b). Studies have shown that the genotype I(1a) is the predominant type in the USA and Europe, whereas type II(1b) is more frequent in the Far East. It is also suggested that type II (1b) is associated with non-responsiveness to interferon therapy. Our hemophiliacs were treated with imported coagulation factors, thus they were probably exposed to the genotypes in the west. There was significant difference in the incidence of HCV type II (1b) among local blood donors and hemophiliacs (P = 0.005). However the difference between the hemophiliacs and the patients with chronic liver disease was not statistically significant. The number of patients in this study was too small to draw any firm conclusions. However the findings highlight the importance of studying the genotypes of patients with Hepatitis C infection due to their relevance in the management of these cases with interferon therapy.

Adolescent↗
PubMed1994

Multiple myeloma: the National University Hospital (NUH) experience.

The aim of this retrospective study was to define the characteristics of local patients with multiple myeloma. Twenty-nine de novo cases were accrued from October 1986 to January 1992 at the National University Hospital of Singapore. Features like median age of presentation, sex distribution, the incidence of IgG, IgA and light chain subtypes were similar to published data. However IgD myeloma appeared to be more common here and it tended to be more advanced at presentation. Objective response rate to treatment with the melphalan-prednisolone combination was about 40% with a median survival of 18 months.

Adult↗
PubMed1993

Prevalence of antibodies to hepatitis C virus in relation to surrogate markers in a blood donor population of Singapore.

Prevalence of antibodies to HCV is studied among a blood donor population in Singapore and its relationship to surrogate markers was examined. Sequential serum samples from 4,091 blood donors were tested for the presence of anti-HCV using the second generation immunoassay (Abbott). 275 random serum samples were tested for anti-HBc and ALT. All the samples positive for anti-HCV were also tested for anti-HBc and ALT. Only 22 of the 4,091 donor samples (0.54%) were repeatedly reactive for anti-HCV. Of the 275 random samples tested, 43 samples (15.6%) were positive for anti-HBc and 24 (8.7%) had ALT levels more than 45 IU/l. None of these 67 samples were positive for anti-HCV. Only 3 of the 22 anti-HCV positive samples (13.6%) were positive for anti-HBc and only 6 samples (27.2%) had ALT level more than 45 IU/l. The prevalence of anti-HCV among the donors is only 0.54% which is much lower than the prevalence of HBV. An important finding is that about 60% of the donors positive for anti-HCV had no detectable surrogate markers. Exclusion of blood donors positive for anti-HBc, if implemented in an area where the prevalence of HBV infection is relatively high will result in the loss of blood donors estimated to be 15.6% and the use of raised ALT will result in a further loss of 6.1% of the blood donors.

Adolescent↗
PubMed1990

Multiple myeloma in the University Hospital: a retrospective study of biodata, clinical, laboratory and radiological profiles, 1980-1987.

A retrospective study of 37 cases of multiple myeloma admitted from 1980 to 1987 to the University Hospital Kuala Lumpur, Malaysia, was carried out to analyse the biodata, clinical presentation, laboratory and radiological profiles. The cases were selected after they had satisfied preset diagnostic criteria. The mean age was 60 years. There was no sex or ethnic preponderance. The most common symptom was bone pain. Pallor was detected in 73% of the patients. Haemoglobin was less than 120 g/L in 95%, and ESR was greater than 100 mm/hr in 70% of cases. Bone marrow and trephine biopsies were diagnostically important. Hypercalcaemia occurred in seven cases out of which three were IgA myelomas. Either serum creatinine or blood urea was raised in nearly 50% of cases. The most common heavy chain paraprotein was IgG while Kappa light chain was the commoner light chain type. 86% of cases had osteolytic lesions. These findings are, in general, similar to those of larger studies on multiple myeloma.

Aged↗
PubMed1990

Splenic lymphoma with hypersplenism--a case report.

A 47-year old man had hypersplenism from massive splenomegaly, the cause of which was undetermined for 2 years. He was initially asymptomatic though there was mild pancytopenia. However, 18 months after presentation he manifested both clinical and haematological deterioration, almost succumbing to sepsis. Splenectomy finally provided a definite diagnosis of follicular lymphoma and also restored his blood counts to within normal range.

Humans↗
PubMed1990

Myelodysplastic syndrome: a review from University Hospital, Kuala Lumpur.

Twenty patients with Myelodysplastic Syndrome (MDS) were diagnosed in University Hospital, Kuala Lumpur over a 5 year period. They were subclassified using the French American British (FAB) criteria. 90% of the patients were above 40 years old and the sex ratio was about equal. The predominant presenting symptom was anaemia and there was paucity of physical signs at presentation. Patients with 'aggressive' subtypes of MDS i.e. refractory anaemia with excess blasts (RAEB), refractory anaemia with excess blasts in transformation (RAEB(-)+) and chronic myelomonocytic leukaemia (CMML) had more frequent thrombocytopenia and neutropenia and their marrow pictures frequently had dysmegakaryopoiesis and dysgranulopoiesis as compared to more the "benign" subtypes i.e. refractory anaemia (RA) and refractory leukaemic anaemia with ringed sideroblasts (RARS). Four patients had leukaemic transformation and all of them came from the 'aggressive' subtypes. The current views on treatment of MDS are discussed.

Adolescent↗
PubMed1989

Adult neuroblastoma: a case report.

Neuroblastoma is an uncommon malignancy in adult life as compared with childhood. A case of Stage IV neuroblastoma in a 24-year-old Chinese man seen at the University Hospital, Kuala Lumpur is reported. The diagnosis was based on characteristic histological features seen in an excised lymph node with metastatic involvement and an elevated urinary metanephrine level. The finding of a suprarenal mass on computerised axial tomographic scan supported an adrenal origin. Other diagnostic aids which help to distinguish this tumour, especially the less differentiated forms, from other "small, dark, round cell tumours" are discussed.

Adult↗
PubMed1988

Megaloblastic anaemia--a review from University Hospital, Kuala Lumpur.

During a 5 year period, 28 adult patients with megaloblastic anaemia (MA) were treated in University Hospital. 71% of the patients were Indians. Symptoms of anaemia was the main presenting complaint in 18 (64%) of patients while in 2 patients peripheral neuropathy was the main problem. Pancytopenia was a common finding (present in 18 (64%) patients) while 6 (21%) patients had severe thrombocytopenia (less than 20 x 10(9)/L). The peripheral blood morphology provided important diagnostic clues i.e. macrocytes and/or hypersegmented neutrophils seen in most patients. Concurrent iron deficiency 'dampened' the megaloblastic picture. Though most patients suffered from MA of nutritional origin, 3 patients were diagnosed to have pernicious anaemia and 2 patients had myelodysplastic syndrome. Important practice points were detection of concurrent infection and hypokalemia which necessitated appropriate treatment. The controversy of blood transfusion in treatment of MA and the importance of reassessing patients after treatment were highlighted.

Anemia, Macrocytic↗