Body composition, muscular strength and cardiovascular strength of the second-year medical students at faculty of medicine Siriraj Hospital, Mahidol University.

Objective: This study was conducted to evaluate Siriraj medical students’ fitness thereby obtaining data for promoting greater physical fitness in Siriraj medical students. Methods: Physical fitness among second year medical students academic year 2008 was measured by methods including body mass index (BMI) and waist to hip circumference ratio in determining body composition, hand grip dynamometer in determining muscular strength, heart rate as well as blood pressure before and after performing a YMCA step test in determining cardiovascular strength and a questionnaire in determining the lifestyle of medical students. Results: Average BMI and cardiovascular strength of both male and female medical students were within normal range compared to those of Thai. However, muscular strength of both male and female medical students was relatively low compared to those of average Thai as sixty-six per cent of them had exercise less than twice a week. Conclusion: Siriraj medical students need more physical exercises to improve their physical fitness. It is important to persuade medical students to pay more attention to their health, which will eventually make them to be healthy doctors in the future.

Glycemic and lipid responses to glucomannan in Thais with type 2 diabetes mellitus.

OBJECTIVE: To evaluate the benefits of glucomannan supplement on glycemic and lipid controls in type 2 diabetic patients. MATERIAL AND METHOD: A single-blind, placebo-controlled, crossover trial with two treatments separated by a 2-week washout period was performed in 10 men and 10 women with type 2 diabetes mellitus. Two separated protocols of experiments were sequentially followed. Initially, purified glucomannan (1 g) or placebo was ingested 30 min before 75-g glucose load to evaluate their effects on glucose absorption and insulin secretion in oral glucose tolerance test (OGTT). Later, the glycemic and lipid changes after 4-week intervention with 3 g/day glucomannan comparing to the placebo were determined. The standard OGTT was performed before and after ending of each intervention. RESULTS: Glucomannan taken before performing the OGTT can lower the rise of blood glucose and insulin from 1 to 2 hour in comparison with the placebo, though a statistically significance of insulin was not achieved. Long-term glucomannan supplement significantly reduced the 120-min glucose area under the curve of OGTT. Glucomannan also decreased the rise of low-density lipoprotein cholesterol (LDL-C). Reductions of HOMA-insulin resistance index and body mass index were detected in glucomannan-treated group though the former was shown only in females. No within- and between-group differences of insulin, fructosamine, and other lipids were observed in glucomannan- nor placebo- treated groups. CONCLUSION: In type 2 diabetes, pre-prandial glucomannan ingestion attenuated a rise of blood glucose without significantly affecting insulin levels. Long-term supplement of glucomannan to the regular diabetic regimen lessened post challenge glucose AUC and impeded the rise of LDL-C. Supplement of glucomannan may be beneficial to the glycemic and lipid controls in type 2 diabetes mellitus.

Estrogen reduced blood glucose in high fat-fed mice: An animal model of type 2 diabetes.

Objective: This study aims to produce a mouse model of type 2 diabetes by using high fat diet. The C57BL/6J mouse strain can develop type 2 diabetes by putting on high fat diet. Methods: A group of C57BL/6J male mice were fed with a high fat diet (53% energy by fat) while another group was fed with normal diet (4.5% energy by fat). Results: At the 16th week of feeding study, the high fat-fed mice developed type 2 diabetes and had higher fat-pad weight than the normal diet-fed mice. However, plasma triglyceride (TG) levels of the two groups were not different. High fat-induced diabetic mice were administered 0.2 ตg/g body weight of 17-β estradiol for 2 weeks. Their fasting blood levels were reduced to become lesser than the levels in high-fat fed mice without estrogen. A trend of decrease in plasma TG level of 17β estradiol treated mice was observed. Conclusion: This study demonstrated that high fat diet could induce type 2 diabetes in a mouse model and that estrogen could reduce the fasting blood glucose in these mice.

Assessment of hormonal and metabolic effects of dietary fiber in young Thai women.

OBJECTIVE: To investigate whether daily dietary fiber intake at the reference level has any impact on studied hormones in a population of Thai women. MATERIAL AND METHOD: Twenty-eight healthy Thai women (aged 18-20 years, BMI 18.5-25 kg/m2) with a history of regular menstrual cycles committed themselves to prepared food without changing the usual ratio of three major macronutrients. Dietary fiber from natural source at the amount of 8-10 g/day equal to their regular consumption was added to their daily diet for one menstrual cycle, then, increased to be 25-30 g/day for another 2 successive cycles. A single blood sample on midluteal day (day 18-23) was obtained in all three cycles. Plasma luteinizing hormone, follicle stimulating hormone, prolactin, estradiol, progesterone, cortisol, and insulin together with total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides were analyzed. RESULTS: The measured hormones and lipids did not change significantly when compared between a control and two experimental cycles (p > 0.05). CONCLUSION: Short-term consumption of 25-30 g/day fiber diet as recommended by the Reference Daily Intake (RDI) in a Thai population did not alter the studied hormones and lipids thus did not create any health problems.

Postprandial leptin response to Thai meals with different macronutrient mixtures.

The objective of this study was to investigate the postprandial response of leptin, an appetite-regulating hormone, to different macronutrient mixtures in Thai meals. A within-subject repeat measurement was performed. Two groups of healthy Thais (10 men and 10 women in each group) received a single meal of equal calories composed either a high carbohydrate, low fat, low protein diet (HC-LFLP, carbohydrate:fat:protein = 70%:15%:15%) or a low carbohydrate, high fat, high protein diet (LC-HFHP, carbohydrate:fat:protein = 20%:50%:30%). Fasting and 30-minute interval postprandial blood levels of leptin, insulin and glucose were measured for a 2-hour period. In comparison to the LC-HFHP meal, the HC-LFLP meal produced a greater increase in glucose and insulin levels, but halted leptin from decreasing. Postprandial leptin levels were suppressed by a LC-HFHP meal but not by a HC-LFLP meal. The reduced leptin in conjunction with lower glucose and insulin levels may encourage overeating in habitual LC-HFHP diet consumers.

In vitro study of insulin secretion from mouse pancreatic islets-siriraj experiences.

Pancreatic islet isolation and culture technique are tools for direct investigation of the effects of substances on insulin secretion. Glucose is a well known insulin stimulating substance from the pancreatic islet. This study aims to demonstrate the first success (in Thailand) in islet isolation with intact insulin secretion from a mouse pancreas using collagenase P enzyme and histopaque separation. Isolated islets were cultured in RPMI 1640 for 24 hours before undergoing a glucose stimulation test. Glucose at five different concentrations (2.8, 5.6, 10, 15 and 20 mM glucose was higher than with 2.8mM basal glucose concentration. Insulin secretion increased about 1.7 to 3.5 fold from a basal level of 2.8 mM glucose without any difference in insulin content at any glucose concentrations used. To our knowledge, these data demonstrate the first success in mouse pancreatic islet isolation and culture in Thailand. This technique can be used as a tool for further investigation of the in vitro effects of substances such as plants or new drugs on insulin secretion.

Association between estrogen receptor concentration in breast cancer tissue and bone mineral density.

Both bone and the breast are major target tissues of estrogen actions. The biological actions of estrogen depend on the interaction between estrogen and estrogen receptors (ER) in the target tissues. Therefore, ER concentration in tissues such as breast cancer might be associated with the amount of bone mass. The present study was aimed to examine whether there is a relationship between ER concentration in breast cancer tissue (ER-BCA) and bone mineral density (BMD). Forty-seven pre-menopausal and 34 post-menopausal women with newly diagnosed breast cancer were studied. The ER-BCA ranged from 0 to 339 fmol/mg cytosol protein (mean +/- SD = 68.6 +/- 97.0). Pearson's correlation analyses showed that ER-BCA negatively correlated to BMD of the spine (r = -0.251, p = 0.024), forearm (r = -0.341, p = 0.002), hip (r = -0.373, p = 0.001) and total body (r = -0.317, p = 0.004) in all 81 women. In 47 pre-menopausal women, the ER-BCA negatively correlated to the hip (r = -0.455, p = 0.001) and total body (r = -0.395, p = 0.006) but not to the spine and forearm BMD. Whereas, in 34 post-menopausal women, the ER-BCA negatively correlated to forearm BMD (r = -0.399, p = 0.019). Stepwise multiple regression analyses showed that the ER-BCA independently correlated to hip BMD in all 81 women (r = -0.373, p < 0.01) and in pre-menopausal women (r = -0.486, p < 0.001) and independently correlated to forearm BMD in post-menopausal women (r = -0.399, p < 0.05). The results of this study suggest that the presence of high estrogen receptor concentration in breast cancer tissue might induce a deleterious effect on bone mass particularly in pre-menopausal women.

Estrogen receptor-alpha mRNA in primary breast cancer: relationship to estrogen and progesterone receptor proteins and other prognostic factors.

The estrogen receptor (ER)-alpha protein and ER mRNA were measured in 314 primary breast cancer patients by enzyme immunoassay (EIA) and reverse-transcription polymerase chain reaction (RT-PCR) assay, respectively. The positivity of ER protein was 53% while of ER mRNA was 37.6%. A significant positive association between ER phenotype and ER mRNA was observed (r = 0.40, p < 0.0001) with a positive-negative agreement between them of 71.8%. The percentage of ER-negative, progesterone receptor (PR)-positive breast tumors was 1.9% by EIA and 7% by RT-PCR assay. This may indicate a difference in ER variants in these studied patients. The ER protein and ER mRNA status were inversely related to tumor size and p53 positivity. Also, ER protein was frequently positive in patients with a higher number of lymph node invasions, well to moderate nuclear differentiated tumor cells and negative c-erbB-2 status. The difference of the ER or ER mRNA status regarding ages, menopausal status, tumor stages and histological types was not shown. In the present study, ER mRNA did not demonstrate a closer relationship to prognostic indicators of breast cancer than ER protein. Before including the ER mRNA assessment in routine investigations of breast cancer, its relationship to prognostic factors and survival outcome should be further assessed with a higher number of patients and a longer follow-up time.

Expression of p53, c-erbB-2 and cathepsin D in relation to hormone receptors in primary breast cancer.

The immunohistochemical expression of p53, c-erbB-2, and cathepsin D oncogene proteins was examined in 494 primary breast carcinomas. This study aimed to investigate an association of expression of these three proteins with other variables known to be related to poor prognosis as well as with 5-year disease free survival (DFS). P53, c-erbB-2, and cathepsin D alone or in combination was negatively correlated with the presence of estrogen and progesterone receptors in breast cancer tissues. Alteration of these oncogenes rendering an expression of the proteins may affect the synthesis of steroid receptor proteins during the course of breast cancers. However, their significance as predictors of 5- year DFS was not achieved in this group of patients. Lymph node invasion was the only independent indicator for recurrent or metastatic breast carcinoma.

Preliminary study of clinical value of serum prolactin in association with CEA, CA15-3, MCA and c-erbB-2 in primary breast cancer.

The clinical value of circulating prolactin as a marker for the diagnosis of primary breast cancer compared with other serum markers was evaluated in Thai women. Forty women with primary breast cancer, 20 women with benign breast disease and 20 normal women were included in the study. Single serum levels of prolactin, CEA, CA 15-3, MCA and c-erbB-2 were simultaneously measured. At 95% specificity, prolactin gave the highest diagnostic sensitivity (92.5%) compared with a sensitivity of 10-30% obtained from the other markers studied but did not correlate with any of them. Concentrations of CEA, CA 15-3, MCA and c-erbB-2 in 40 breast cancer tissue were related to each other by multiple regression analysis and they also showed good positive and negative agreement among subjects. Thus, measurement of a single marker among four of them should be economically and clinically appropriate. CEA when compared with other markers, showed a better relationship with clinicopathological parameters e.g. tumor diameter and axillary lymph node involvement. This preliminary study suggests that prolactin and CEA may be a good combination of paired serum markers for the early detection of breast cancer. A prospective study should be performed in order to demonstrate the exact relationship of elevated blood prolactin levels and the risk of breast cancer in the Thai population.

The development of a reverse transcription polymerase chain reaction system for detection of estrogen receptor in breast cancer.

Estrogen receptor (ER) is widely used as an indicator of prognosis and response to endocrine treatment of primary breast cancer. ER phenotypes detected by conventional assays may not reflect their capability on binding specifically to estrogen response elements of target DNA. The reverse transcription polymerase chain reaction (RT-PCR) has been shown to offer the sensitive and specific method for measuring the ER mRNA in breast cancer. The ER-mutant gene which is positively detected in breast tumor by biochemical or immunocytochemical assays may be negatively shown by RT-PCR or vice versa. PCR technique for examining expression of ER mRNA may therefore provide a good screening method for detection of functioning ER that will affect the selection of appropriate treatment and prognosis of breast cancer patients. We have developed RT-PCR assay using b2-microglobulin as internal control for detection and relative-quantitation of ER mRNA in breast cancer tissue. Preliminary results show that the developed assay provides a sensitive and specific method for detection of ER expression in breast tumor. Also, the assay procedure is simple, rapid, non- expensive and required very small amount of breast cancer tissues.

Serum and tissue markers in primary breast cancer.

Thirty-three primary breast cancers were analyzed for prognostic markers, Immunohistochemical assay of c-erbB-2 oncoprotein was performed in formalin fixed paraffin-embedded tissue. Enzyme immunoassay and radioreceptor assay for ER and PR were respectively done in tumor cytosol. Pre-opertive blood sample obtained from this group of patients were analyzed for CEA, CA15-3 and MCA levels. About 54% of tumor had c-erbB-2 positive staining. Direct association was observed between tumor size, pathological stage, serum CEA levels and c-erbB-2 expression. No significant association existed between the expression of c-erbB-2 and lymph node invasion, histological type, ER and PR status, serum CA15-3 or MCA levels. Increased incidence of c-erbB-2 overexpression among breast cancer patients with large tumor, more advanced stage and elevated CEA level suggests its value for indicating of greater tumor aggressiveness.

Cortisol and 17-hydroxyprogesterone in saliva.

Radioimmunoassays of cortisol and 17OHP in saliva may replace the blood and urine measurements. The steroids in saliva obtained from normal subjects showed similar patterns of circadian rhythm, menstrual profiles and the responses to dynamic tests as seen in blood. The concentrations of these two salivary steroids measured here are similar to those previously reported and the advantages of salivary steroid measurements are suggested for routine clinical assessment of adrenocortical function.

Plasma prolactin, gonadotropins sex steroids and cortisol determined during reproduction period in Thai subjects.

Radioimmunoassay measurements of plasma hormones : gonadotropins (Gn), Luteinizing hormone (LH) and follicle stimulating hormone (FSH), prolactin (PRL), cortisol and sex hormones i.e. estradiol (E2) and progesterone (P4) in women and testosterone (T) in men were simultaneously performed to establish normal range data of hormone secretions in Thai subjects. Values of hormonal profiles in the females during the normal menstrual cycles or in 118 healthy males of reproductive age were similar to data described for Thai and other nationalities by previous investigators. Data obtained in the present study may be useful as a guide for interpretation of normal and abnormal hormone secretions in Thai subjects, although minor inter-laboratory discrepancies in results may exist.