Investigations into the Creation of a Strip Test capable of monitoring Glucose concentration using Tears

Background: To create a strip test to monitor blood sugar levels in diabetics using tears. For most diabetics, the current available methods for testing blood glucose are either invasive, inconvenient or both. A test such as glucose tear strip would improve patient compliance and disease control. Methods: 50 diabetic and 50 non-diabetic subjects, participated in this study. A sample of tears was collected from each subject's right eye using a glass microcapillary tube. Following tear collection, the blood glucose level of each subject was tested and recorded. At the end of sample collection 100 samples of tears were tested for glucose concentration. The results were examined to determine the correlation of glucose in tears to that in blood. Results: Based on this study conducted, the average TG concentration in non-diabetics was found to be 1.89 0.54 mg/dL and in diabetics, 3.10 0.55 mg/dL, whilst the PPBG concentration in non-diabetics and diabetics was found to be 118.60 4.67 mg/dL and 233.98 16.21 mg/dL respectively. Conclusion: There was a significant difference in between the glucose concentration in tears and the glucose concentration in blood. There was a weak correlation between the two variables. The development of a non-invasive, convenient and patient-friendly method of monitoring glucose concentration may not be possible but with advancements in technology, a strips sensitive to low concentrations of glucose present in tears can be developed.

Investigating the impact of the local health care system in controlling blood glucose levels and preventing complications in patients with type 2 diabetes

OBJECTIVES: To determine if the local health-care system controls blood glucose levels and prevents complications in Trinidadian type 2 diabetic subjects. This study also focused on assessing the structures that are established to monitor blood glucose levels of type 2 diabetics in the public health facilities. DESIGN AND METHODS: This study was a cross-sectional retrospective study of 388 adult type 2 diabetic participants. Participants were taken from all four Regional Health Authorities (RHAs) in Trinidad. RESULTS: The mean and SD of fasting blood glucose of participants, over the 3 year monitoring period, was 197ñ61.67 and a standard error of ñ3.13. The blood glucose levels of the participants did not change significantly (p = 0.848). Results showed that the higher the fasting blood sugar values, the more complications a patient presented. Fasting blood sugar values were the standard for monitoring blood glucose levels, however HbA1c and other measures mandated under protocol were absent. CONCLUSIONS: Across all Regional Health Authorities in Trinidad, fasting blood sugar values were found to be out of control and remained high. It was noted that the higher a patient’s fasting blood sugar values, the more complications they presented.

Adipose tissue infiltration in skeletal muscle: age patterns and association with diabetes among men of African ancestry

BACKGROUND: Although obesity is strongly associated with diabetes, the greater prevalence of diabetes in persons of African ancestry than in those of other ancestries cannot be explained simply by differences in total or central adiposity. OBJECTIVE: We examined whether skeletal muscle composition is associated with diabetes in 1249 men of African ancestry aged >or=40 y. DESIGN: Anthropometry and fasting serum glucose were measured, and lower-leg skeletal muscle composition was assessed with peripheral quantitative computerized tomography (pQCT). RESULTS: The prevalence of diabetes in this population was high (21%). We observed an age-associated adipose tissue remodeling in skeletal muscle and greater intermuscular (IMAT) and lesser subcutaneous (SAT) adipose tissue area with advancing age (P < 0.0001). Multivariate stepwise logistic regression identified more IMAT and less SAT to be significantly associated with a greater prevalence of diabetes. Even among normal-weight men [body mass index (BMI; in kg/m(2)) < 25], diabetic men had significantly (P = 0.01) more IMAT than did those without diabetes. Greater IMAT was also associated with a greater prevalence of hyperglycemia in men with a family history of diabetes than in those without such history (P for interaction = 0.02). CONCLUSIONS: These findings underscore the independent associations of subcutaneous and intermuscular fat among men of African ancestry, an effect that may be modified by a family history of diabetes. Further studies are needed to identify the genetic and physiologic mechanisms that influence the distribution and remodeling of adipose tissue in skeletal muscle with aging.'

Influence of aerobic treadmill exercise on blood glucose homeostasis in noninsulin dependent diabetes mellitus patients.

The role of treadmill exercise on blood glucose homeostasis in noninsulin dependent diabetes mellitus (NIDDM) were studied using males between age of 45 and 60 years (X-52), who wereclinically and biochemically-confirmed cases of NIDDM were taken into study group. Control group comprised of 10 males between age group of 45 to 60 (X-53) years. All the subjects were assessed by physician and were investigated to confirm diabetic status. The whole study period was extendedfor 6 weeks. The significant decrease in postprandial blood sugar (44.4mg per cent for the study group and 32.2mg per cent for the control group) with a significant inter group difference (P<0.05) was observed. The mean decrease in fasting blood sugar 39.4mg per cent for the study group and 27.4mg per cent for the control group), with a marginal inter group difference (P<0.05) was observed. The treadmill exercise was found to be a definite tool in addition to drug and diet in glycemic control.

Glycaemic control and cardiovascular risk factors among patients with Type 1 diabetes mellitus in Trinidad [abstract]

Healthcare providers working at the primary care setting are often faced with the challenges of providing standard medicare in the absence of adequate resources and facilities. We assessed long-term glycaemic control and cardiovascular risk factors among patients with Type 1 diabetes mellitus at primary care clinics in an attempt to suggest an intervention programme to prevent long-term diabetic complications. Twenty-five (14 females, 11 males, mean age: 53.7 ñ 3.2 years) patients with Type 1 diabetes mellitus (mean (SE) duration: 15.7 ñ 2.0 years) attending two primary care clinics in Trinidad were studied after an overnight fast. Weight, height, waist and hip circumferences and blood pressure were measured and blood sample was taken for glucose, glycated haemoglobin, total cholesterol, triglyceride, HDL-cholesterol, LDL-cholesterol and creatinine determinations. There were no significant differences in the glycaemic exposure and the measured cardiovascular risk factors between male and female patients (p> 0.05). However, more than one-half (56 percent) of the patients had truncal obesity while 96 percent had glycated haemoglobin levels> 7.0 percent. The prevalence rates of hypercholesterolaemia (84 percent), hypertriglyceridaemia (28 percent) and increased LDL-cholesterol levels (88 percent) were high. About 48 percent of the patients had diastolic blood pressure> 83mmHg while 40 percent had total-cholesterol/HDL-cholesterol ratio greater than 6. We report that patients with Type 1 diabetes mellitus attending primary care clinics in Trinidad had poor glycaemic control and high levels of classical cardiovascular risk factors. These patients are at great risk of progressing to cardiovascular disease and therefore efforts at strict glycaemic control and protection against long-term diabetic complications should be intensified at primary care levels. (AU)

Effect of water extract of Coraili (Momordica charantia) on blood glucose levels in Sprague Dawley Rays [abstract]

Water extracts from the fruit of the coraili plant, Mormordica charantia, have been reported to have hypoglycaemic effect. The fruit of this plant is eaten as a vegetable by man. Significant lowering of blood glucose levels has been observed following the oral administration of coraili fruit extracts. However, some authors have shown that there are no beneficial hypoglycaemic effect from fruit extracts. In this experiment, water extract of the entire coraili fruit was administered orally to alloxan-diabetic Sprague Dawley Rats ad libitum for 7 hours. The rats were placed on normal diet during the experiment. Results showed that 7 hours after the administration of this extract, blood glucose levels dropped significantly. It was also observed that, 7 hours after the discontinuation of the administration of the extract in alloxan-diabetic rats, blood glucose levels rose close to the pre-administration levels. The implications of these findings will be discussed. (AU)

The effect of yoga exercise therapy on metabolic activity and oxidative stress indicators in non-insulin dependent diabets mellitus (NIDDM) patients [abstract]

OBJECTIVE: To evaluate the effort of yoga traditional exercises on indicators of oxidative damage and on anti-oxidative enzyme system in patients with NIDDM. METHODS: Ninety-four NIDDM volunteers were divided randomly into two groups: traditional and yoga exercise (female to male 5:1, age 50 to 70 yeras, with 2-5 years of duration of diabetes and without clinical complications). Both groups twice weekly for six months with similar nutritional support. Blood samples were taken at the beginning, and six months following exercise treatments and the following were determined: glycaemia by glucose oxidase (automatic analyser), microalbuminuria by semiquantative methods, creatinine by kinetic method, malondialdehyde (MDA) by products of thiobarbituricacid, superoxide dismutase (SOD) by kinetic method - the inhibition of pyrogallol, phospholipase A2 by colorimetry, protein oxidation (POX) by the method of Reznicky and Pucker. RESULTS: There was a reduction of glycaemia in the yoga group after 6 months (8.84 vs 8.35 mmol/l), while there was an increase in the traditional group 8.74 vs 9.51 mmol/l). The concentration of creatinine and microalbumin decreased in both groups notably in the yoga group. (AU)

Knowledge, beliefs, practices, blood pressure and blood glucose control in women with diabetes mellitus [abstract]

OBJECTIVE: To determine the knowledge, beliefs, practices, blood pressure and blood glucose control among women with diabetes mellitus attending a specialist medical clinic. METHOD: A 43-item pre-tested questionnaire was administered to a purposive sample of 28 (26.4 percent) of women attending the University Hospital of the West Indies Diabetes Clinic in May/June 2001. Weight (wt), height (ht), blood pressure (BP), fasting blood glucose (FBG) and two hour post-prandial blood glucose (2hpp), diet and activity were recorded. Body mass index (BMI, wt/ht2) was calculated. RESULTS: Median age of 57 years, range, 21-85 years; median time since diagnosis was 14.5 years, range, 0.5-51 years. Only 27 percent of patients had BP controlled to ó135/85 mm/Hg. There was an association between systolic BP and BMI (r= 0.43, p<0.05). The majority of the patients were inactive, overweight or obese: median BMI, 30.3 kg/m2. The majority did not follow a diabetic diet and had no recent contact with a dietitian. There was an association between reported intake of sucrose and 2hpp (r= 0.75, p<0.001). The majority (82 percent) did not take alcohol; 14 percent smoked cigarettes. Only 28.6 percent were controlled to FBG ó 8 mmol/l and 2 hpp ó10 mmol/l. Sixty-seven percent of the patients were on insulin; 21.3 percent used a glucometer. Medications were missed a median of two days per month. There were inverse associations between years since diagnosis and number of days per month that medications were missed (r= -0.39, p<0.05) and knowledge scores and age (r= -0.47, p<0.01). There were associations between knowledge, practice and educational level (p<0.01). The doctor was the main source of information. The majority reported having had ECG (57 percent), blood cholesterol and renal function tests (64 percent) in the past year. The majority (57 percent) reported never having had a foot examination; 32 percent reported never having had an eye examination. CONCLUSION: The majority of these patients were inactive and obese with limited control of blood glucose and blood pressure. Although fairly compliant with medication, there was little adherence to therapeutic guidelines regarding diet, exercise and maintenance of normal weight. Closer attention should be given to foot and eye examinations for early detection of complications. Closer monitoring and counselling of patients in these areas is recommended. (AU)

Management of diabetes mellitus in three settings in Jamaica

OBJECTIVES: To evaluate the quality of diabetic care in three clinics (one of them private and the other two public) in Jamaica, which is a middle-income country with a high prevalence (13 percent) of diabetes. METHODS: During a six-week census in 1995 at the three clinics we collected data retrospectively on a total of 437 diabetic patients. One of the clinics was a specialist public-hospital clinic ("SPMC"), one was a private group general practice ("PRMC"), and one was a public polyclinic ("PUBMC"). The patients median age ranged from 56 years at SPMC, 9.2 years at PRMC, and 6.3 years at PUBMC. RESULTS: Fewer than 10 percent of the patients wer controlled with diet alone. Insulin was the most commonly prescribed agent at SPMC (46 percent), compared to 7 percent each at the two other clinics. Sulfonylurea drugs alone or in combination with metformin were the most common agents at PUBMC and PRMC. Overall, 40 percent of the patients had satisfactory blood glucose control of (<8 mmol/L fasting or <10 mmol/L postprandial). There was no significant difference among the clinics in the proportion of patients with satisfactory blood glucose control (P= 0.26). A blood glucose measurement had been recorded in the preceding year in 84 percent of the patients at SPMC, 79 percent at PRMC, and 67 percent at PUBMC. Glycosylated hemoglobin was infrequently measured: 16 percent at SPMC, 10 percent at PRMC, and 0 percent at PUBMC. Overall, 96 percent of patients have had surveillance for hypertension, and 81 percent had had surveillance for proteinuria. Surveillance for foot and retinal complications was generally infrequent and had been noted in patients' clinical records most commonly at SPMC (14 percent for foot complications, and 13 percent for retinal complications). The staff at the three clinics seldom advised the diabetic patients on diet, exercise, and other nonpharmacological measures, according to the clinics' records. CONCLUSIONS: The management of diabetes in Jamaica fell short of international guidelines. Our results also indicate the need to better sensitize health care professionals to these standards in order to reduce the burden of diabetes. (AU)

A comparison of the accuracy of two glucometers for the estimation of venous blood glucose - Poster abstract

OBJECTIVE: To determine the accuracy, in ward use, of the Precision QID glucometer in the estimation of venous blood glucose and to compare it with the Prestige glucometer currently in use. METHODS: Paired measurements of capillary blood glucose were done by various doctors. medical students, and nurses using the two glucometers for each subject and a simultaneously obtained venous blood sample measured by the laboratory as the reference value. Forty-three data triplets were obtained. Reproducibility of results was tested on 15 measurements of a heparinized blood sample. Before the experiments, operators were interviewed about their knowledge of the precautions and limitations associated with glucometer use. They were then trained. RESULTS: Linear correlation with the laboratory reference line was found as follows (all values in mmol/l): 1 = 1.25P + 0.6 (r = 0.961) and 1 = 1.1Q - 0.7 (r = 0.975), where L = laboratory value, P = Prestige value, Q = Precision value. A reproducibility study of 15 measurements done on a heparinized whole blood sample for each glucometer showed for Prestige, a mean of 3.1 with SD of 0.26 and for Precision, a mean of 4.7 with SD of 0.18. Operators were ignorant of most of the precautions and limitations associated with glucometer use. CONCLUSIONS: The Precision QID glucometer was superior to the Prestige glucometer for the estimation of venous blood glucose. Operators need to be carefully trained before being allowed to use glucometers.(AU)

Relationships of fasting and postload glucose levels to sex and biased against detection of diabetes in women?

OBJECTIVE: To compare, in men and women, the prevalence of undiagnosed type 2 diabetes assessed using criteria from the American Diabetes Association (ADA) and the World Health Organization (WHO) and to investigate risk factors associated with fasting and 2-h postload plasma glucose. RESEARCH DESIGN AND METHOD: Data from two companion surveys of Europeans, South Asians, and Afro-Caribbean in west London were used. A total of 4,367 men and women aged 40-64 years who were not known to have diabetes underwent an oral glucose tolerance test after an overnight fast. The prevalence of undiagnosed diabetes was estimated using the ADA (fasting plasma glucose > or = 7.0 mmol/l) and WHO (2-h postload glucose > or = 11.1 mmol/l) criteria for epidemiologic studies. The association of body fat and usual alcohol intake with plasma glucose and diabetes prevalence was assessed. RESULTS: Compared with the WHO criterion, the ADA criterion gave a higher prevalence of diabetes in men (6.4 vs 4.7 percent) but a lower prevalence in women (3.3 vs. 4.2 percent). In Afro-Caribbeans, the sex difference in diabetes prevalence was reversed. Women had significantly lower fasting glucose than men despite higher 2-h glucose levels. Alcohol intake was positively associated with fasting glucose in men and women but not with 2-h glucose levels. CONCLUSIONS: The new ADA criterion, based on fasting glucose alone, does not take account of sex differences in metabolic response to fasting or possible artifactual effects on fasting glucose. With ADA criterion, alcohol intake was significant risk factor for diabetes in our study population; this was not the case with the WHO criterion.(AU)

The effect of glycaemic control on peripheral blood flow in diabetics -Poster presentation

Many studies have shown that persistent uncontrolled blood glucose predisposes to several diabetic complications. The aim of this study was to determine the influence of blood glycated haemoglobin levels on plasma fibrinogen concentration - (PFC), relative plasma viscosity (RPV) and ankle blood flow (Qak) in a group of diabetic patients with vascular complications compared with non-diabetic control (C). Qak was measured by the technique of venous occlusion plethysmography. PFC was determined by a clot-weight method. RPV was determined by capillary viscometry. Glycaemic control was determined by measuring glycated haemoglobin levels (GHb). Patients were divided into three categories of glycaemic control, namely good (GHb 4 - 8 percent), moderate (GHb > 8 - 12 percent) and poor (GHb > 12 percent). Qak, PFC and RPV were compared among diabetics with and without peripheral occlusive arterial disease (POAD) and/or neuropathy of various categories of glycaemic control. Qak in diabetics without peripheral occlusive arterial disease (POAD) with good glycaemic control was significantly higher (p <0.05) than that of non-diabetic (C). Qak differed significantly (p < 0.05) between non-neuropathic diabetics (without POAD) (D) with good and poor or good and moderate glycaemic control. PFC was significantly higher (p < 0.05) in all diabetics with POAD, in D with moderate glycaemic control and in neuropathic diabetes (without POAD) (ND) with poor control than in C. RPV was significantly higher (p < 0.05) in D with moderate control and poorly controlled neuropathic diabetics with POAD than in C. RPV differed significantly (p < 0.05) between D with moderate and poor control. The results suggest that in the absence of POAD, an initial vasodilatation occurs in diabetics. The decrease in arterial flow as metabolic control worsens, may be a consequence of the simultaneous increase in plasma viscosity.(AU)

Yoga exercise versus traditional exercise in the control of non-insulin diabetes mellitus - Poster presentation

The sample population was selected from 3 municipals of Havana City. The population size was selected using the programme EP16 with the option statcalc. From a population size of 17,068 diabetics, a sample size of 100 diabetics was calculated as the minimum population size required to obtain a confidence level of 95 percent. Patients were divided into two groups (yoga and traditional group) and were matched according to the following criteria: Age +/- 5 years, Sex, Type of treatment, Evolution of NIDDM, BMI. The two groups of 63 diabetics were matched according to the criteria described above and were then grouped as "yoga exercise group" and "traditional exercise group". Biochemical analysis was done at the start of the investigation, and included: HDL - C Tryglyceride, LDL - C, Total cholesterol, Glycated haemoglobin, Insulinic receptors, Microalbuminuria, Blood glucose, quantification of T3, T4 Insulin, GH, and TSH, Oxidative stress enzymes serum, creatinine. The Second Stage: Both groups had similar diet and practised their respective physical exercise at the same duration and frequency for periods of 3 and 6 months. The biomedical analysis was done at these intervals. The biochemical analysis at the start showed: In most cases there were alterations in lipid metabolism, renal function as seen as hyperlipidaemia and hypercortisolaemia and a reduction in the union and internalization of insulin in the receptors of lymphocytes. There was a correlation between GH and T4. These findings show that it is necessary to deepen the investigation of these patients as there exists a difference in the laboratory results and the clinical manifestations of endocrine metabolc diseases.(AU)

Effects of aqueous extract of neem (azadirachta indica a. juss) on streptozotocin induced diabetic rats

Neem (Azadirachta indica) products have been extensively used in Ayurvedic medicine in India for many centuries. To elucidate a common folkloric saying, "two leaves a day keeps diabetes away", thirty male Wistar rats weighing between 180 to 250 g were randomly assigned to three equal groups. To induce diabetes, rats in groups II and III received a single intraperitoneal dose of Streptozotocin (STZ) at a rate of 50 mg/Kg body weight. After 5 days of STZ treatment, diabetic rats in group III received 0.4 percent aqueous neem extract in drinking water for 188 days. Rats in group III received citrate buffer and served as drinking water for 188 days. Rats in group I received citrate buffer and served as control. All the rats were maintained under standard management conditions and received water/extract and dry pellet diet ad libitum. The animals were sacrificed after 290 days for histological examination of various tissues. The results of the study revealed that (1) the mean blood glucose levels showed a decreasing trend (p>0.05) during 48-77 days of neem treatment and also after 51 days of discontinuation of the neem treatment (2) the percent gain in body weight in neem treated diabetic rats was lower than in diabetic rats (20v/s 80 percent) (p value). In conclusion, the aqueous extract of neem showed significant improvements in the body weights and lessened mortality in STZ induced diabetic rats but could not normalise blood glucose levels.(AU)

Association of waist circumference with risk of hypertension and type 2 diabetes in Nigerians, Jamaicans, and African-Americans

OBJECTIVE: Prior studies have supported that waist circumference correlates better with visceral adipose tissue and is a better predictor of cardiovascular disease than are BMI and waist-to-hip ratio. In this study, we reexamine the role of waist size on the risk of hypertension and type 2 diabetes in African-origin populations from three contrasting environments. RESEARCH DESIGN AND METHODS: A cross-sectional survey was conducted of 5,042 men and women 25-74 years of age from Nigeria, Jamaica, and the U.S. The relationship between waist, blood pressure, and fasting blood glucose was assessed using multiple linear regression analyses. Logistic regression analyses using sex-specific empirical waist cut-points were used to determine the risks of hypertension and type 2 diabetes. RESULTS: Waist circumference was positively correlated with blood pressure and fasting blood glucose (P < 0.05). Increasing waist quartiles were significantly associated with higher risks of hypertension in the three populations, as estimated from age-adjusted odds ratios obtained from sex-specific logistic regression models. A highly elevated risk of type 2 diabetes-10-fold for Jamaican men and 23-fold for African-American women - was observed in the comparison of lowest to highest quartiles of waist circumference. CONCLUSIONS: Substantial reduction in hypertension and diabetes in men and women is achievable if the waist size is decreased in these populations. Intervention programs designed to reduce waist circumference through lifestyle modification, including exercise and diet, may have significant public health significance in reducing the incidence of hypertension and adult-onset diabetes in these populations (Au)

The Trp64 A rg mutation of the B3- Adrenergic Receptor Is associated with hyperglycemia and current body mass index in Jamaican women

The Trp64Arg mutation the the beta3-adrenergic receptor (beta3-AR) has been linked to earlier onset of non-insulin-dependent diabetes mellitus (NIDDM), insulin resistance, abdominal obesity, and an increase capacity to gain weight in some European and Japanese populations. We studied the prevalence of the mutation and its association with NIDDM and obesity in our population, in which both rates are high, especially in women. The frequency of the homozygous mutation was 1.53 percent, and of the Arg allele, 10.5 percent. Rates were similar in men and women. Significantly higher body mass index (BMI), weight, hip circumference, and fasting and postchallenge 2 hour blood glucose concentrations were associated with the presence of the Arg allele in women but not in men. The association with weight and hip measurements and with hyperglycemia was present only in women aged less than 55 years. In multivariate analysis, the mutation was associated with the BMI and sex in a model that also included age. The variation in fasting and 2 hour blood glucose levels were predicted by beta3-AR, gender, age and BMI. These results suggest that the presence of the mutation contributes to obesity and hyperglycemia in our female population.(AU)

Weight and body composition changes during pregnancy in Barbadian women - abstract

Weight gains occur during normal pregnancy in women with free access to food. Maternal nutrition status prior to conception and during pregnancy is a critical determinant of foetal growth and pregnancy outcomes. These gains reflect changes in the composition of the maternal body as well as changes in the products of conception. There are limited data from the West Indies about maternal nutritional status during pregnancy as well as the factors determining changes in body composition and pregnancy weight gain. We report the results of a prospective study of 342 pregnant Barbadian women conducted between August 1994 and February 1996 which assessed nutritional changes during pregnancy and their impact on glucose metabolism. This report is, however, limited to the changes observed in nutritional indices. At registration, age and parity were strongly analysed demonstrated that change in weight between registration (at a median time of 15 weeks gestation) and 36 weeks gestation and postpartum, were independently and inversely associated with BMI and age. Parity was not found to be independently associated with weight change. Changes in body composition were examined by deriving estimates of fat and lean mass. Estimated fat mass gains were consistent with those reported from well-nourished Western societies, and were mainly determined by initial BMI. We also observed gains in lean mass as a consequence of pregnancy. (AU)

The hyperglycaemic effect of s-nitroso-glutathione via the release of nitric oxide - abstract

Recent evidence suggests that nitric oxide (NO) is an important factor in both inflammatory-induced and streptozotocin-induced diabetes. In this study we investigated the pharmacological activity of S-nitroso-glutathoine (GNSO), a carrier of NO, on blood glucose level in 10 mongrel dogs, and measured their plasma nitrate concentration after the administration of GSNO. S-nitroso-glutathoine elicited a dose-dependent increase in blood glucose level (15 - 102 percent) which was paralled with an increase in nitrate production. The blood glucose levels at 2.0 and 2.5 hrs in an Oral Glucose Tolerance Test were significantly higher in dogs administered with GNSO than those of the controls (p<0.05). There was also a significant increase in plasma nitrate on administration of GSNO (35 - 100 percent). The plasma nitrate concentrations from 0.5hr to 2.5hrs were significantly higher compared to the controls (p<0.05). The hyperglycaemic effect of GSNO was enhanced with the co-adminstration of ascorbic acid. This resulted in 5 - 30 percent increase in blood glucose concentration. The blood glucose levels at 2hrs in dogs after the co-administration of 35mg kg of GSNO (P<0.05). The data from this study showed that persistent hyperglycemia can be an unwanted side effect of GSNO administration and that the glucose concentration should be closely monitored when this drug is used to treat patients(AU)

Insulin response and gestational diabetes related to maternal age? - abstract

Most cases of gestational diabetes are found in women older than 30 years. Insulin response generally decreases with increased age. To correlate the relationship between maternal age; insulin response and subsequent development of gestational diabetes, 120 pregnant women were classified into three age groups; ages 18-24 years, 25-29 years and o30 years. All women were classified as normal weight when adjusted for expected pregnancy weight gain. The three groups were administered a 50g glucose screen at 27 weeks of gestation. Blood samples were taken 1 hour after ingesttion. Analyses were done for glucose, c-peptide and insulin. Patients in the age group in 18 - 24 years had mean ñSD glucose concentration of 5.6ñ 1.0 mmol/l and showed the greatest insulin response with a mean ñSD of 160ñ 24æU/ml. Patients in the age group 25 - 29 years had a mean glucose value of 6.4ñ 1.0 mmol/l and the mean insulin value of 148ñ 31æU/ml was less than that of the younger group. The oldest women had the lowest mean insulin value of 100ñ 49æU/ml and showed some general glucose intolerance with mean glucose value of 8.1ñ 1.0mmol/l. A significant difference (p=0.001) was formed in insulin values when the women in the age groups 18-24 years and 25-19 years were compared. However the difference was greater (p=0.000002) when the women in the age groups 18 - 24 years and o30 years were compared. A 4.25 percent prevalence rate of gestational diabetes was found among the oldest women. Our findings that glucose tolerance and insulin response are lowest in older pregnant women support the concept that gestational diabetes in more prevalent in older gravidas. (AU)

The hyperglycaemic effect of S-nitroso-glutathione via the release of nitric oxide

Nitric oxide is a pathogenic factor of inflammatoryislet cell death in Type I diabetes. Insulin-Dependent Diabetes Mellitus (IDDM) is mediated by an autoimmune mechanism or inflammatory process that is characterized by destruction of beta cells. Incubation of pancreatic islet cells with activated macrophages, which release large amounts of nitric oxide, causes the death of the islet cells. When the cells are exposed to the nitric oxide donor, sodium nitroprusside, lysis of the cells occur in a concentration and time-dependent manner. In this study we investigated the pharmacological activity of S-nitroso-glutathione (GSNO), a carrier of nitric oxide on blood glucose levels in dogs, and measured the plasma nitrate/nitrite concentration in the dog serum after the administration of GSNO using an automated method. The blood glucose level was measured using the glucose oxidase assay. S-nitroso-glutathione elicited a dose-dependent increase in blood glucose levels which was paralleled with an increase in nitrate/nitrite production. The blood glucose levels at 2.0 hrs and 2.5 hrs of the Oral Glucose Tolerance Test (OGTT) were significantly higher in dogs administered with GSNO than those of the controls (p<0.05). Post-prandial blood glucose levels in dogs administered with 35 mg per kg body weight of GSNO were 7.2 + 0.9mmol/l and 7.1 + 0.7mmol/l, compared with 4.8 + 0.2mmol/l and 4.6 + 0.2mmol/l in controls. The hyperglycaemic effect was more pronounced on adminstration of 35 mg per kg body weight of GSNO and ascorbic acid. Post-prandial blood glucose levels in the dogs after administration of 50 mg per body weight, at 2.0 hrs and 2.5 hrs were 9.2 + 0.7mmol/l and 9.3 + 0.3mmol/l, respectively. The basal nitrate/nitrite concentration was 12.4 + 0.4umol. On administration of 35 mg per kg body weight of GSNO, there was a 35 - 60 percent increase in the plasma nitrate/nitrite concentration. The plasma nitrate/nitrite concentration at 2.0 hrs to 2.5 hrs ranged from 16.8 + 1.0umol. The plasma nitrate/nitrite concentration increase by 100 percent on administration of 50 mg per kg of GSNO. This study confirms that S-nitroso-glutathione is a hyperglycaemic compound which affects the blood glucose levels in dogs. The hyperglycaemic effects can be caused by the nitric oxide action on the pancreatic islet cells (AU).