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Glucose Concentration (glucose + concentration)
Kinds of Glucose Concentration Selected AbstractsEffects of Glucose Concentration on in vitro Fertilization in BALB/c MiceREPRODUCTION IN DOMESTIC ANIMALS, Issue 6 2003HT Wu Contents BALB/c mice are widely used in genetic, tumour and immunological studies. However, the mice demonstrate a lower reproduction rate, low fertility and small litters, because of their highly genetic homozygoisty. Based on in vitro fertilization (IVF), a routine technique for biomedical studies, it is worth to evaluate the effects to BALB/c mice on IVF efficiency. In order to test the genetic factor affecting the IVF efficiency of BALB/c, four reciprocal IVF tests of BALB/cByJ and FVB/NCrl mice were performed. The results showed that the average fertility of IVF sponsored by FVB/NCrl spermatozoa was 69.6%, but only 12.1% was obtained from BALB/cByJ strain. Effect of glucose contained in the culture medium to the IVF efficiency of BALB/cByJ was also evaluated. The results showed that the fertility of BALB/cByJ spermatozoa incubated with 0, 2.7, 5.5, 11.1 and 22.2 mm of glucose in the TYH medium were 6.8, 9.9, 13.9, 32.7 and 22.2%, respectively. It is showed that IVF efficiency of BALB/cByJ spermatozoa could be improved depending on the concentration of glucose in the IVF medium. According to the results, it is beleived that lower IVF of BALB/cByJ mice might be due to the genetic defect in spermatozoa and increasing glucose in the IVF medium which significantly affect the IVF efficiency of BALB/cByl via activating the spermatozoa. [source] Vitreous Fluid and/or Urine Glucose Concentrations in 1335 Civil Aviation Accident Pilot Fatalities,JOURNAL OF FORENSIC SCIENCES, Issue 3 2009Arvind K. Chaturvedi Ph.D. Abstract:, During aviation accident investigations, vitreous fluid and urine samples from pilot fatalities are analyzed for glucose and blood for hemoglobin A1c (HbA1c) to monitor diabetic pilots and to discover other pilots with undiagnosed/unreported diabetes. The prevalence of elevated glucose concentrations in fatally injured pilots was evaluated by searching the Civil Aerospace Medical Institute's Toxicology Database for the period 1998,2005. Out of 1335 pilots involving 363 vitreous fluid, 365 urine, and 607 vitreous fluid and urine analyses, 43 pilots had elevated glucose in vitreous fluid (>125 mg/dL) and/or in urine (>100 mg/dL). Of the 20 pilots whose blood samples were analyzed, nine had >6% HbA1c,four were known diabetics, and five were unknown diabetics. Urinary glucose levels were elevated in all 13 known hyperglycemic pilots. A considerable number of pilots (30 of 43) had elevated glucose and HbA1c (5 of 20), suggesting undiagnosed/unreported diabetic conditions. [source] Role for the Pineal and Melatonin in Glucose Homeostasis: Pinealectomy Increases Night-Time Glucose ConcentrationsJOURNAL OF NEUROENDOCRINOLOGY, Issue 12 2001S. E. La Fleur Abstract The effects of melatonin on glucose metabolism are far from understood. In rats, the biological clock generates a 24-h rhythm in plasma glucose concentrations, with declining concentrations in the dark period. We hypothesized that, in the rat, melatonin enhances the dark signal of the biological clock, decreasing glucose concentrations in the dark period. We measured 24-h rhythms of plasma concentrations of glucose and insulin in pinealectomized rats fed ad libitum and subjected to a scheduled feeding regimen with six meals equally distributed over the light/dark cycle and compared them with previous data of intact rats. Pinealectomy dampened the amplitude of the 24-h rhythm in plasma glucose concentrations in rats fed ad libitum, and abolished it completely in rats subjected to the scheduled feeding regimen, while plasma insulin concentrations did not change under both conditions. Pinealectomy abolished the nocturnal decline in plasma glucose concentrations irrespective of whether rats were fed ad libitum or subjected to the scheduled feeding regimen. Melatonin replacement restored 24-h mean plasma glucose concentrations in pinealectomized rats that were subjected to the scheduled feeding regimen but, interestingly, it did not restore the 24-h rhythm. Melatonin treatment also resulted in higher meal-induced insulin responses, probably mediated via an increased sensitivity of the ,-cells. Taken together, our data demonstrate that the pineal hormone, melatonin, influences both glucose metabolism and insulin secretion from the pancreatic ,-cell. The present study also demonstrates that removal of the pineal gland cannot be compensated by mimicking plasma melatonin concentrations only. [source] Comparison of the effect of ketamine added to bupivacaine and ropivacaine, on stress hormone levels and the duration of caudal analgesiaACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 10 2005M. Akbas Background:, The aim of this study was to compare bupivacaine 0.25% and ropivacaine 0.2%, singly and in combination with ketamine, for caudal administration in children. Duration of analgesia, the need for other analgesics and the stress response were measured. Methods:, Eighty children were ramdomized into four groups of twenty. The bupivacaine group received bupivacaine 0.25% and the ketamine/bupivacaine group received bupivacaine 0.25% plus 0.5 mg/kg ketamine. The ropivacaine group received ropivacaine 0.2%, and the ketamine/ropivacaine group received ropivacaine 0.2% plus 0.5 mg/kg ketamine. The duration of analgesia and analgesic requirements were recorded for each group, as were peri-operative and post-operative concentrations of the stress hormones insulin, glucose and cortisol. Results:, Ketamine, added to either bupivacaine or ropivacaine for caudal analgesia, gave a longer duration of analgesia (P < 0.05) than bupivacaine or ropivacaine alone. In all groups, blood insulin concentration was increased, and cortisol concentration reduced. Glucose concentration was significantly increased in all groups (P < 0.05). Conclusions:, Ketamine can safely be added to ropivacaine 0.2% or bupivacaine 0.25% for caudal anesthesia in order to prolong duration of analgesia and reduce the need for additional analgesics. Stress hormone levels are partially attenuated. [source] Interstitial glucose in skeletal muscle of diabetic patients during an oral glucose tolerance testDIABETIC MEDICINE, Issue 1 2005M. Frossard Abstract Aim The presence of a transcapillary arterial,interstitial gradient for glucose (AIGglu) in skeletal muscle may be interpreted as a consequence of intact cellular glucose uptake. We hypothesized that the AIGglu decreases in Type 2 diabetes mellitus as a consequence of insulin resistance, whereas it remains intact in Type 1 diabetes. Methods Glucose concentrations were measured in serum and interstitial space fluid of skeletal muscle during an oral glucose tolerance test (OGTT) in patients with Type 1 and Type 2 diabetes and in young and middle-aged healthy volunteers, using microdialysis. Results The area under the curve for glucose in serum (AUCSE) was higher than in interstitial space fluid of skeletal muscle (AUCMU) in healthy young (AUCSE = 1147 ± 332 vs. AUCMU = 633 ± 257 mM/min/ml; P = 0.006), healthy middle-aged volunteers (AUCSE = 1406 ± 186 vs. AUCMU = 1048 ± 229 mM/min/ml; P = 0.001) and in Type 1 diabetic patients (AUCSE = 2273 ± 486 vs. AUCMU = 1655 ± 178 mM/min/ml; P = 0.003). In contrast, in Type 2 diabetic patients AUCSE (2908 ± 1023 mM/min/ml) was not significantly different from AUCMU (2610 ± 722 mM/min/ml; P = NS). Conclusion The present data indicate that AIGglu is compromised in Type 2 diabetes in contrast to Type 1 diabetes where it appears to be normal. Because no changes in muscle blood flow were detected, insulin resistance appears to be the main cause for the observed decreased AIGglu in skeletal muscle in Type 2 diabetic patients. [source] Energy substrates in bovine oviduct and uterine fluid and blood plasma during the oestrous cycleMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 3 2008S.A. Hugentobler Abstract Up to 40 percent of cattle embryos die within 3 weeks of fertilization but there is little or no published information on the composition of the oviduct and uterine fluids essential for their survival during this time. We have measured the concentrations of the energy substrates, glucose, lactate, and pyruvate in cattle oviduct fluid on Days 0, 2, 4, and 6 and uterine fluid on Days 6, 8, and 14 of the oestrous cycle and corresponding blood samples. Oviduct and uterine fluids were collected in situ. Glucose concentrations in oviduct and uterine fluids were similar on all days and lower than in plasma (P,<,0.05). Oviduct lactate concentration was up to eightfold higher than uterine or plasma concentration (P,<,0.01). Oviduct pyruvate concentrations were similar on all days and lower than plasma concentrations on Days 0 and 2 (P,<,0.005). Pyruvate concentrations were similar in the uterus and in plasma except on Day 14 when the concentration in plasma was higher (P,<,0.05). There were no associations between systemic progesterone or oestradiol and glucose, lactate or pyruvate. There was a linear positive relationship (P,<,0.001) between oviduct fluid secretion rate and oviduct glucose concentration and a linear negative relationship (P,<,0.001) between oviduct fluid secretion rate and oviduct lactate, but no association between uterine fluid secretion rate and energy substrates. The different concentrations and associations between the energy substrates in oviduct and uterine fluids and blood plasma indicate a differential regulation of the secretion of these energy substrates by the oviduct and uterine epithelium. Mol. Reprod. Dev. 75: 496,503, 2008. © 2007 Wiley-Liss, Inc. [source] Neonatal blood glucose concentrations in caesarean and vaginally delivered term infantsACTA PAEDIATRICA, Issue 10 2010Ronella Marom Abstract Background:, Little is known about the glucose concentrations at and after birth of infants delivered by caesarean section (CS), when compared with infants born vaginally (VD). Aim:, To compare venous cord blood glucose concentrations of term infants born after elective CS to infants born by VD. We studied the null hypothesis that mode of delivery does not affect neonatal blood glucose values. Methods:, We compared cord blood glucose concentrations in healthy term infants born after VD (n = 16) or by elective CS (n = 21). Glucose concentrations were obtained immediately at birth from the umbilical cord. Kruskal,Wallis was used to compare glucose concentrations and demographic variables between the groups. Results:, Gestational age was 39.6 ± 0.8 weeks in VD group vs. 38.7 ± 0.9 weeks in CS group, and birthweight was 3359 ± 494 vs. 3500 ± 528 g. Cord blood glucose concentration was higher in VD (81.3 ± 16.9 mg/dL) than CS infants (70.3 ± 9.7 mg/dL, p = 0.039). The change in blood glucose concentration over the first 2-h of life differed significantly between the two groups, being an increase in CS versus a decrease in VD infants (,3.5 ± 15.2 vs. ,15.4 ± 24.6 mg/dL, p = 0.013). Conclusions:, Glucose concentrations in VD infants are higher than in infants born by elective CS without labour. [source] Fetal cyclic motor activity in diabetic pregnancies: Sensitivity to maternal blood glucoseDEVELOPMENTAL PSYCHOBIOLOGY, Issue 1 2003Steven S. Robertson Abstract Spontaneous fetal movement in the last third of human gestation is dominated by irregular oscillations on a scale of minutes (cyclic motility, CM). The core properties of these oscillations are stable during the third trimester of gestation in normal fetuses, but disrupted by poorly controlled maternal diabetes. Here we investigated whether fetal CM is linked to short-term instabilities in maternal glucose metabolism. The fetuses of 40 mothers with type I (n,=,28) or gestational (n,=,12) diabetes were studied one to six times between 27 and 40 postmenstrual weeks of gestation. Fetal movement and maternal blood glucose concentration were measured during two separate periods of fetal activity in each session. Fetal CM was quantified with spectral analysis. Early in the third trimester, changes in the rate of oscillation in fetal CM between the two periods of activity were inversely related to changes in maternal blood glucose levels. Fetal CM was unrelated to concurrent maternal blood glucose levels at any point in the third trimester. The pattern of results suggests that disruption of the temporal organization of spontaneous fetal motor activity in pregnancies complicated by maternal diabetes represents an acute response to fluctuations in the metabolic environment rather than an alteration of CM development. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 42: 9,16, 2003. [source] An exploratory study of the effect of using high-mix biphasic insulin aspart in people with type 2 diabetesDIABETES OBESITY & METABOLISM, Issue 7 2009U. Dashora Objective:, To compare blood glucose control when using biphasic insulin aspart (BIAsp) three times a day (using 70/30 high-mix before breakfast and lunch), with biphasic human insulin (BHI, 30/70) twice daily in adults with type 2 diabetes already treated with insulin. Research design and methods:, In a 60-day, open-label, crossover study, people with insulin-treated type 2 diabetes [n = 38, baseline haemoglobin A1c 8.3 ± 0.9 (s.d.) %] were randomized to BIAsp three times a day before meals, as BIAsp 70 (70% insulin aspart and 30% protamine-complexed insulin aspart) before breakfast and lunch and BIAsp 30 (30/70 free and protamine-complexed insulin aspart) before dinner, or to human premix insulin (BHI) 30/70 twice a day before meals. A 24-h in-patient plasma glucose profile was performed at the end of each 30-day treatment period. The total daily insulin dose of BIAsp regimen was 110% of BHI and the doses were not changed during the study. Results:, There was no difference between BIAsp and BHI in geometric weighted average serum glucose over 24 h [7.3 vs. 7.7 mmol/l, BIAsp/BHI ratio 0.95 (95% CI 0.88,1.02), not significant (NS)], but daytime geometric weighted average glucose concentration was significantly lower with the BIAsp regimen than with BHI [8.3 vs. 9.2 mmol/l, BIAsp/BHI ratio 0.90 (0.84,0.98), p = 0.014]. The mealtime serum glucose excursion was also lower with BIAsp than with BHI with statistically significant differences at lunchtime [difference ,4.9 (,7.0 to ,2.7) mmol/l, p = 0.000); the difference in glucose excursions above 7.0 mmol/l was also significant [,5.8 (,8.3 to ,3.2) mmol/l, p = 0.000). The proportion of participants experiencing confirmed hypoglycaemic episodes was similar between regimens (42 vs. 43%, NS). Conclusions:, An insulin regimen using high-mix BIAsp (BIAsp 70) before breakfast and lunch and BIAsp 30 before dinner can achieve lower blood glucose levels during the day through reduced mealtime glucose excursions in particular at lunchtime than a twice-daily premix regimen. [source] Rosiglitazone is more effective than metformin in improving fasting indexes of glucose metabolism in severely obese, non-diabetic patientsDIABETES OBESITY & METABOLISM, Issue 6 2008A. Brunani Aim:, In obese patients, the diet-induced weight loss markedly improves glucose tolerance with an increase in insulin sensitivity and a partial reduction of insulin secretion. The association with metformin treatment might potentiate the effect of diet alone. Methods:, From patients admitted to our Nutritional Division for diet programme, we selected obese, non-diabetic, uncomplicated patients with age 18,65 years and body mass index 35,50 kg/m2 and studied the effects of a 6-month pharmacological treatment with either metformin (850 mg twice daily) or rosiglitazone (4 mg twice daily) on possible changes in body weight, fat mass, glucose and lipids metabolism. Results:, A significant weight loss and reduction of fat mass was demonstrated with metformin (,9.7 ± 1.8 kg and ,6.6 ± 1.1 kg) and also with rosiglitazone (,11.0 ± 1.9 kg and ,7.2 ± 1.8 kg), without fluid retention in either treatment group. Rosiglitazone administration induced a significant decrease in glucose concentration (4.7 ± 0.1 vs. 4.4 ± 0.1 mmol/l, p < 0.005) and insulin-circulating level (13.6 ± 1.5 vs. 8.0 ± 0.,7 ,U/ml, p < 0.005), an increase in insulin sensitivity as measured by homeostatic model assessment (HOMA) of insulin sensitivity (68.9 ± 8.8 vs. 109.9 ± 10.3, p < 0.005) with a concomitant decrease in ,-cell function as measured by HOMA of ,-cell function (163.2 ± 16.1 vs. 127.4 ± 8.4, p < 0.005). In contrast, metformin did not produce any significant effect on blood glucose concentration, insulin level and HOMA2 indexes. No adverse events were registered with pharmacological treatments. Conclusion:, Our study shows that in severely obese, non-diabetic, hyperinsulinaemic patients undergoing a nutritional programme, rosiglitazone is more effective than metformin in producing favourable changes in fasting-based indexes of glucose metabolism, with a reduction of both insulin resistance and hyperinsulinaemia. In spite of previous studies reporting rosiglitazone-induced body weight gain, in our study the joint treatment with diet and rosiglitazone was accompanied by weight loss and fat mass reduction. [source] High glucose activates pituitary proopiomelanocortin gene expression: possible role of free radical-sensitive transcription factorsDIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 4 2007Koichi Asaba Abstract Background Hyperglycemia is recognized as a metabolic stress, and indeed it is known to stimulate hypothalamo-pituitary-adrenal (HPA) axis, a representative anti-stress system, in patients with diabetes mellitus or in animal models of hyperglycemia. Thus, we tried to clarify the molecular mechanism of glucose-induced HPA axis activation. Methods We studied the effect of high glucose on the transcriptional regulation of proopiomelanocortin (POMC) gene that encodes adrenocorticotropic hormone, a central mediator of HPA axis, using AtT20 corticotroph cell line in vitro. Results We found that high glucose concentration (24 mM) significantly stimulated the 5,-promoter activity of POMC gene. The effect was promoter-specific, and was mimicked by nuclear factor-kappaB (NF-,B)- or AP1-responsive promoters but not by cAMP-responsive element or serum-response element-containing promoters. Furthermore, the stimulatory effect of high glucose on POMC gene was eliminated by NF-,B and AP1 inhibitors, suggesting the involvement of the transcriptional factors. The POMC 5,-promoter has the canonical NF-,B consensus sequence, and gel shift assay showed the binding of NF-,B to the element. Finally, the effect of high glucose was completely abolished by treatment with a radical quencher 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPOL). Conclusions Our data suggest that hyperglycemia activates POMC gene expression, at least partly, via NF-,B/AP1, and that high-glucose-induced free radical generation may mediate the activation of these transcription factors, which in turn stimulates the transcription of POMC gene. Copyright © 2006 John Wiley & Sons, Ltd. [source] Glucose sensors: a review of current and emerging technologyDIABETIC MEDICINE, Issue 3 2009N. S. Oliver Abstract Glucose monitoring technology has been used in the management of diabetes for three decades. Traditional devices use enzymatic methods to measure glucose concentration and provide point sample information. More recently continuous glucose monitoring devices have become available providing more detailed data on glucose excursions. In future applications the continuous glucose sensor may become a critical component of the closed loop insulin delivery system and, as such, must be selective, rapid, predictable and acceptable for continuous patient use. Many potential sensing modalities are being pursued including optical and transdermal techniques. This review aims to summarize existing technology, the methods for assessing glucose sensing devices and provide an overview of emergent sensing modalities. [source] Continuous Subcutaneous Glucose Monitoring System in diabetic mothers during labour and postnatal glucose adaptation of their infantsDIABETIC MEDICINE, Issue 4 2008E. Stenninger Abstract Aims To assess a new technique for continuous monitoring of glucose concentration during labour in diabetic mothers. A second objective was to study maternal glucose levels in relation to postnatal glucose adaptation and the need for intravenous (IV) glucose treatment in the newborn infant. Methods Fifteen pregnant women with insulin-treated diabetes mellitus participated in this prospective pilot study. To measure their glucose control during labour we used the Continuous Subcutaneous Glucose Monitoring System (CGMS; Medtronic, Minneapolis, MN, USA) to calculate the mean glucose concentration and the area under the curve (AUC) in the last 120 min before delivery. All infants of these women were transferred to the neonatal care unit for early oral feeding and blood glucose measurements up to 14 h after delivery. Infants received IV glucose if blood glucose values were repeatedly < 2.2 mmol/l. Results All women coped well with the CGMS monitoring. AUC 0,120 min before delivery, mean glucose concentration 0,120 min before delivery and cord plasma insulin level were all significantly associated with the need for IV glucose in the newborn children. Conclusions In this study we found an association between maternal glucose concentrations during labour and postnatal glucose adaptation and need for IV glucose treatment in the infants. Online monitoring of glucose levels during delivery might help us to achieve maternal normoglycaemia and further reduce the risk of postnatal hypoglycaemia in the offspring. [source] A method for assessing quality of control from glucose profilesDIABETIC MEDICINE, Issue 7 2007N. R. Hill Abstract Aim As the practice of multiple assessments of glucose concentration throughout the day increases for people with diabetes, there is a need for an assessment of glycaemic control weighted for the clinical risks of both hypoglycaemia and hyperglycaemia. Methods We have developed a methodology to report the degree of risk which a glycaemic profile represents. Fifty diabetes professionals assigned risk values to a range of 40 blood glucose concentrations. Their responses were summarised and a generic function of glycaemic risk was derived. This function was applied to patient glucose profiles to generate an integrated risk score termed the Glycaemic Risk Assessment Diabetes Equation (GRADE). The GRADE score was then reported by use of the mean value and the relative percent contribution to the weighted risk score from the hypoglycaemic, euglycaemic, hyperglycaemic range, respectively, e.g. GRADE (hypoglycaemia%, euglycaemia%, hyperglycaemia%). Results The GRADE scores of indicative glucose profiles were as follows: continuous glucose monitoring profile non-diabetic subjects GRADE = 1.1, Type 1 diabetes continuous glucose monitoring GRADE = 8.09 (20%, 8%, 72%), Type 2 diabetes home blood glucose monitoring GRADE = 9.97 (2%, 7%, 91%). Conclusions The GRADE score of a glucose profile summarises the degree of risk associated with a glucose profile. Values < 5 correspond to euglycaemia. The GRADE score is simple to generate from any blood glucose profile and can be used as an adjunct to HbA1c to report the degree of risk associated with glycaemic variability. [source] Interaction of the G182C polymorphism in the APOA5 gene and fasting plasma glucose on plasma triglycerides in Type 2 diabetic subjectsDIABETIC MEDICINE, Issue 12 2005Y.-D. Jiang Abstract Aim Apolipoprotein AV (APOA5) is an important determinant of plasma triglyceride concentration. This study aimed to investigate the relationship of an amino acid substitution at position 182 (G182C) of the apolipoprotein AV (APOA5) gene with triglyceride concentration in a Taiwanese population. Methods This study enrolled two cohorts: non-diabetic subjects (112 males and 89 females) aged 50.3 ± 11.0 years (mean ± sd) and diabetic subjects (106 males and 96 females) aged 62.1 ± 10.3 years. The relationship between the G182C polymorphism (rs 2075291) and plasma triglycerides was examined. Demographic and metabolic parameters including age, sex, body mass index, fasting plasma glucose and total cholesterol were also obtained. Results The G182C polymorphism was a determinant of plasma triglycerides in both non-diabetic (P = 0.022) and diabetic (P = 0.003) groups, independent of age, gender, fasting plasma glucose, body mass index and total cholesterol. In the diabetic group, this genetic polymorphism interacts significantly (P = 0.032) with fasting plasma glucose concentration on plasma triglycerides after adjustment for age, sex, body mass index and total cholesterol. Conclusions In conclusion, the G182C polymorphism of the APOA5 gene affects plasma triglycerides in both non-diabetic and diabetic populations. The observed interaction of gene and glycaemic control further indicates a multifactorial nature of clinical phenotypes in subjects with Type 2 diabetes. Diabet. Med. (2005) [source] Screening for diabetes in Indigenous populations using glycated haemoglobin: sensitivity, specificity, post-test likelihood and risk of diseaseDIABETIC MEDICINE, Issue 7 2005K. G. Rowley Abstract Aims Screening for diabetes using glycated haemoglobin (HbA1c) offers potential advantages over fasting glucose or oral glucose tolerance testing. Current recommendations advise against the use of HbA1c for screening but test properties may vary systematically across populations, according to the diabetes prevalence and risk. We aimed to: (i) characterize the properties of test cut-offs of HbA1c for diagnosis of diabetes relative to a diagnosis based on a fasting plasma glucose concentration of 7.0 mmol/l for high-risk Indigenous populations; and (ii) examine test properties across a range of diabetes prevalence from 5 to 30%. Methods Data were collected from Aboriginal and Torres Strait Islander communities in Australia and a Canadian First Nations community (diabetes prevalence 12,22%) in the course of diabetes diagnostic and risk factor screening programmes (n = 431). Screening test properties were analyzed for the range of HbA1c observed (3,12.9%). Results In separate and pooled analyses, a HbA1c cut point of 7.0% proved the optimal limit for classifying diabetes, with summary analysis results of sensitivity = 73 (56,86)%, specificity = 98 (96,99)%, overall agreement (Youden's index) = 0.71, and positive predictive value (for an overall prevalence of 18%) = 88%. For diabetes prevalence from 5 to 30% the post-test likelihood of having diabetes given HbA1c = 7.0% (positive predictive value) ranged from 62.7 to 93.2%; for HbA1c < 7.0%, the post-test likelihood of having diabetes ranged from 4.5 to 27.7%. Conclusions The results converge with research on the likelihood of diabetes complications in supporting a HbA1c cut-off of 7.0% in screening for diabetes in epidemiological research. Glycated haemoglobin has potential utility in screening for diabetes in high-risk populations. [source] Effects of acute hyperglycaemia on anorectal motor and sensory function in diabetes mellitusDIABETIC MEDICINE, Issue 2 2004A. Russo Abstract Aims To determine the effects of acute hyperglycaemia on anorectal motor and sensory function in patients with diabetes mellitus. Methods In eight patients with Type 1, and 10 patients with Type 2 diabetes anorectal motility and sensation were evaluated on separate days while the blood glucose concentration was stabilized at either 5 mmol/l or 12 mmol/l using a glucose clamp technique. Eight healthy subjects were studied under euglycaemic conditions. Anorectal motor and sensory function was evaluated using a sleeve/sidehole catheter, incorporating a barostat bag. Results In diabetic subjects hyperglycaemia was associated with reductions in maximal (P < 0.05) and plateau (P < 0.05) anal squeeze pressures and the rectal pressure/volume relationship (compliance) during barostat distension (P < 0.01). Hyperglycaemia had no effect on the perception of rectal distension. Apart from a reduction in rectal compliance (P < 0.01) and a trend (P = 0.06) for an increased number of spontaneous anal sphincter relaxations, there were no differences between the patients studied during euglycaemia when compared with healthy subjects. Conclusions In patients with diabetes, acute hyperglycaemia inhibits external anal sphincter function and decreases rectal compliance, potentially increasing the risk of faecal incontinence. Diabet. Med. 21, 176,182 (2004) [source] Glucose intolerance and associated factors in Mongolia: results of a national surveyDIABETIC MEDICINE, Issue 6 2002J. Suvd Abstract Aims Prevalence of glucose intolerance,diabetes and impaired glucose tolerance (IGT),and of related conditions such as obesity and hypertension, was studied in six population samples in Mongolia in 1999. Methods Diagnosis of glucose intolerance was made on the basis of 2-h blood glucose concentration, according to criteria recommended by the latest report of a WHO Expert Group. Results Crude prevalence of diabetes was 2.9% (2.6% in men and 3.2% in women). Prevalence of IGT was 10.2% (9.3% in men and 10.8% in women). Age standardization to the standard world population of Segi resulted in a total sample prevalence of 3.1% for diabetes and 9.2% for IGT. Prevalence of abnormal glucose tolerance differed according to district of residence. Approximately one-third of the subjects with diabetes were diagnosed prior to the survey. Of those who were diagnosed previously, approximately one-half were not under any form of treatment. Subjects with abnormal glucose tolerance were older, more obese and had higher blood pressure and prevalence of hypertension than those with normoglycaemia. One-half of men and almost one-half of women were hypertensive. Three-quarters of the diabetic subjects were hypertensive. One-third of all subjects were centrally obese. Considering the conditions of principal interest,glucose intolerance, hypertension and obesity,one-half of all subjects demonstrated one or more of these conditions. Central obesity was the most common condition, followed by hypertension and then glucose intolerance. Central obesity and hypertension was the most common combination (17% of all subjects) and 4% exhibited all three conditions. Conclusions Non-communicable diseases are already a threat to public health in Mongolia. Although the prevalence of diabetes is not high by international standards, the relatively high prevalence of IGT suggests that the situation may deteriorate in the future in the absence of concerted action to prevent and control diabetes and related conditions. [source] Gastric emptying in diabetes: clinical significance and treatmentDIABETIC MEDICINE, Issue 3 2002M. Horowitz Abstract The outcome of recent studies has led to redefinition of concepts relating to the prevalence, pathogenesis and clinical significance of disordered gastric emptying in patients with diabetes mellitus. The use of scintigraphic techniques has established that gastric emptying is abnormally slow in approx. 30,50% of outpatients with long-standing Type 1 or Type 2 diabetes, although the magnitude of this delay is modest in many cases. Upper gastrointestinal symptoms occur frequently and affect quality of life adversely in patients with diabetes, although the relationship between symptoms and the rate of gastric emptying is weak. Acute changes in blood glucose concentration affect both gastric motor function and upper gastrointestinal symptoms. Gastric emptying is slower during hyperglycaemia when compared with euglycaemia and accelerated during hypoglycaemia. The blood glucose concentration may influence the response to prokinetic drugs. Conversely, the rate of gastric emptying is a major determinant of post-prandial glycaemic excursions in healthy subjects, as well as in Type 1 and Type 2 patients. A number of therapies currently in development are designed to improve post-prandial glycaemic control by modulating the rate of delivery of nutrients to the small intestine. [source] Integrating an Enzyme-Entrapped Conducting Polymer Electrode and a Prereactor in a Microfluidic System for Sensing GlucoseELECTROANALYSIS, Issue 6 2008Po-Chin Nien Abstract In this study, the flow injection analysis was applied to the enzyme-entrapped electrode on a chip for sensing glucose. The on-chip microelectrode was fabricated by the standard photolithography in clean-room environment and the microfluidic channel height of 100,,m on the chip was formed by poly(dimethylsiloxane). The conducting polymer, poly(3,4-ethylenedioxythiophene), PEDOT, was electropolymerized to entrap the coexisting glucose oxidase (GOD) by cyclic voltammetry (CV). The amount of enzyme entrapped in the matrix measured spectroscopically was about 0.101,U/cm2. At a flow rate of 10,ml/hr, the working electrode (Pt/PEDOT/GOD, WE1) was set at 0.7,V (vs. Ag/AgCl) and sensing of H2O2 was carried out by injecting samples with various concentrations of glucose (Glu). A linear relationship between the sensing current and the glucose concentration, ranging from 1 to 20,mM, was obtained with a sensitivity of 8,nA mm,2 mM,1. The response time and the recovery time were about 30 and 230,s, respectively. For a single-potential test, the oxidation currents of 0.08,mM ascorbic acid (AA) and a blend of 0.08,mM AA and 10,mM Glu reached 31.3% and 145.5%, respectively, when compared with the oxidation current of 10,mM Glu alone. However, when a pre-reactor (WE2) was set at the same potential (0.7,V) before the main enzyme integrated electrode (WE1), the oxidation current for the above mixed solution reached 99.6% of the original one. [source] SECM Visualization of Spatial Variability of Enzyme-Polymer Spots.ELECTROANALYSIS, Issue 19-20 20062: Complex Interference Elimination by Means of Selection of Highest Sensitivity Sensor Substructures, Artificial Neural Networks Abstract Polymer spots with entrapped glucose oxidase were fabricated on glass surfaces and the localized enzymatic response was subsequently visualized using scanning electrochemical microscopy (SECM) in the generator,collector mode. SECM images were obtained under simultaneous variation of the concentration of glucose (0,6,mM) and ascorbic acid (0,200,,M), or, in a second set of experiments, of glucose (0,2,mM) and 2-deoxy- D(+)-glucose (0,4,mM). Aiming at the quantification of the mixture components discretization of the response surfaces of the overall enzyme/polymer spot into numerous spatially defined microsensor substructures was performed. Sensitivity of sensor substructures to measured analytes was calculated and patterns of variability in the data were analyzed before and after elimination of interferences using principal component analysis. Using artificial neural networks which were fed with the data provided by the sensor substructures showing highest sensitivity for glucose, glucose concentration could be calculated in solutions containing unknown amounts of ascorbic acid with a good accuracy (RMSE 0.17,mM). Using, as an input data set, measurements provided by sensing substructures showing highest sensitivity for ascorbic acid in combination with the response of the sensors showing highest dependence on the glucose concentration, the error of the ascorbic acid concentration calculation in solution containing the unknown amount of glucose was 10,,M. Similarly, prediction of the glucose concentration in the presence of 2-deoxy- D(+)-glucose was possible with a RMSE of 0.1,mM while the error of the calculation of 2-deoxy- D(+)-glucose concentrations in the presence of unknown concentrations of glucose was 0.36,mM. [source] Gold Nanoparticles in Nonenzymatic Electrochemical Detection of SugarsELECTROANALYSIS, Issue 19-20 2006Fredy Kurniawan Abstract A nonenzymatic electrochemical sensor for detection of sugars was prepared by layer-by-layer deposition of gold nanoparticles on thin gold electrodes. The deposition was optimized by using of surface plasmon resonance. Voltammetric investigation and impedance spectroscopy of the sensor was performed. Electrical currents caused by glucose on bare gold electrodes and on gold electrodes coated by immobilized gold nanoparticles were compared. The electrodes with nanoparticles display much higher current of glucose oxidation. The oxidation becomes blocked when the swept electrode potential exceeded +0.25,V, during the back scan an oxidation peak is observed again but at less positive potential. The magnitudes of these current peaks are linearly dependent on the glucose concentration; this dependence can be used as calibration for analytical applications. The limit of detection for glucose is below 0.5,mM, the sensitivity (normalized to the macroscopic electrode surface) is about 160,,A,cm,2,mM,1. The sensor response is linear till at least 8,mM of glucose concentration. [source] A study on non-invasive detection of blood glucose concentration from human palm perspiration by using artificial neural networksEXPERT SYSTEMS, Issue 3 2010Hamdi Melih Sarao Abstract: In this paper the relationship between blood glucose concentration and palm perspiration rate is studied as a non-invasive method. A glucose concentration range from 83 mg/dl to 116.5 mg/dl is examined. An artificial neural network (ANN) trained by the Levenberg,Marquardt algorithm is developed to detect the performance indices based on the one- and two-input variables. A data set for 72 volunteers is used for this study. Data of 36 volunteers are used for training the ANN and data of 36 volunteers were reserved for testing. Results of the study are acceptable with an error of 8.38% for the Elman neural network and 8.77% for the multilayer neural network. Therefore, the palm perspiration rate may be used as a good indicator for detecting glucose concentration in blood. This non-invasive method has advantages such as time saving, cost etc. over other methods and it is painless. The results of clinical experiments, follow-up methods and other applications are presented. [source] Recombinant glycodelin carrying the same type of glycan structures as contraceptive glycodelin-A can be produced in human kidney 293 cellsbut not in Chinese hamster ovary cellsFEBS JOURNAL, Issue 15 2000Ingrid M. Van den Nieuwenhof We have produced human recombinant glycodelin in human kidney 293 cells and in Chinese hamster ovary (CHO) cells. Structural analyses by lectin immunoassays and fast atom bombardment mass spectrometry showed that recombinant human glycodelin produced in CHO cells contains only typical CHO-type glycans and is devoid of any of the N,N,- diacetyllactosediamine (lacdiNAc)-based chains previously identified in glycodelin-A (GdA). By contrast, human kidney 293 cells produced recombinant glycodelin with the same type of carbohydrate structures as GdA. The presence of a ,1,4- N- acetylgalactosaminyltransferase functioning in the synthesis of lacdiNAc-based glycans in human kidney 293 cells is concluded to be the cause of the occurrence of lacdiNAc-based glycans on glycodelin produced in these cells. Furthermore, human kidney 293 cells were found to be particularly suited for the production of recombinant glycodelin when they were cultured in high glucose media. Lowering the glucose concentration and the addition of glucosamine resulted in higher relative amounts of oligomannosidic-type glycans and complex glycans with truncated antennae. Human glycodelin is an attractive candidate for the development of a contraceptive agent, and this study gives valuable information for selecting the proper expression system and cell culture conditions for the production of a correctly glycosylated recombinant form. [source] Bacterial competition between a bacteriocin-producing and a bacteriocin-negative strain of Streptococcus bovis in batch and continuous cultureFEMS MICROBIOLOGY ECOLOGY, Issue 3 2006Bruno M. Xavier Abstract A bacteriocin-producing Streptococcus bovis strain (HC5) outcompeted a sensitive strain (JB1) before it reached stationary phase (pH 6.4), even though it grew 10% slower and cell-free bovicin HC5 could not yet be detected. The success of bacteriocin-negative S. bovis isolates was enhanced by the presence of another sensitive bacterium (Clostridium sticklandii SR). PCR based on repetitive DNA sequences indicated that S. bovis HC5 was not simply transferring bacteriocin genes to S. bovis JB1. When the two S. bovis strains were coinoculated into minimal medium, bacteriocin-negative isolates predominated, and this effect could be explained by the longer lag time (0.5 vs. 1.5 h) of S. bovis HC5. If the glucose concentration of the minimal medium was increased from 2 to 7 mg mL,1, the effect of lag time was diminished and bacteriocin-producing isolates once again dominated the coculture. When the competition was examined in continuous culture, it became apparent that batch culture inocula were never able to displace a strain that had already reached steady state, even if the inoculum was large. This result indicated that bacterial selection for substrate affinity was even more important than bacteriocin production. [source] Reversible transition between active and dormant microbial states in soilFEMS MICROBIOLOGY ECOLOGY, Issue 2-3 2001John Stenström Abstract The rate of respiration obtained in the substrate-induced respiration (SIR) method can be divided into the respiration rate of growing (r) and non-growing (K) microorganisms. The fraction of r is generally small (5,20%) in soils with no recent addition of substrates, but can be 100% in soils with high substrate availability. This suggests that substrate availability determines the proportion of biomass between these groups, and implies that transitions between them can take place reversibly. These hypotheses were tested by adding three different amounts of glucose which induced first-order, zero-order, and growth-associated respiration kinetics to three soils at four pre-incubation times (4, 12, 27, and 46 days) before the SIR measurement. An abiotic flush of CO2 in the SIR measurement was detected and corrected for before data analysis. Accumulated CO2 -C over 4 days after glucose addition, corrected for the respiration in unamended controls, corresponded to 41,50% mineralization of the glucose-C, and the relative amount mineralized by each soil was independent of the glucose amount added. The high glucose concentration gave an increased SIR, which reverted to the initial value within 27,46 days. In a specific sample, the maximum respiration rate induced during the pre-incubation, and the amount of organisms transformed from the K to the r state, as quantified in respiration rate units in the SIR measurement, were identical to each other, and these parameters were also highly correlated to the initial glucose concentration. The K,r transition was very fast, probably concurrent with the instantaneous increase in the respiration rate obtained by the glucose amendment. Thereafter, a slow first-order back-transition from the r to the K state ensued, with half-lives of 12, 23, and 70 days for the three soils. The results suggest the existence of community-level controls by which growth within or of the whole biomass is inhibited until it has been completely transformed into the r state. The data also suggest that the microbial specific activity is not related to the availability of exogenous substrate in a continuous fashion, rather it responds as a sharp transition between dormant and fully active. Furthermore, the inherent physiological state of the microbial biomass is strongly related to its history. It is proposed that the normal dynamics of the soil microbial biomass is an oscillation between active and dormant physiological states, while significant growth occurs only at substantial substrate amendment. [source] The response of the yeast Saccharomyces cerevisiae to sudden vs. gradual changes in environmental stress monitored by expression of the stress response protein Hsp12pFEMS YEAST RESEARCH, Issue 6 2008Ildar Nisamedtinov Abstract The response of the yeast Saccharomyces cerevisiae to sudden vs. gradual changes in different environmental stress conditions during both respiratory growth and aerobic fermentative growth in the presence of excess glucose was investigated by monitoring the level and rate of expression of the stress response protein Hsp12p using the fluorescent fusion construct Hsp12p-Gfp2p. The initial expression level and the rate of Hsp12p synthesis was significantly greater under glucose-limited conditions in the chemostat (D<0.14 h,1) compared with when excess glucose was present in the auxostat. Decreasing the dilution rate and the glucose concentration further in the A-stat resulted in increased Hsp12p expression, which was more marked when a rapid rather than a gradual change was affected. Common stress factors such as NaCl, ethanol and elevated temperature caused stress responses in both D-stat and auxo-accelerostat culture. The magnitude of the stress response depended on the stress factor, cultivation conditions as well as the rate of change of the stress factor. The rate of Hsp12p synthesis increased due to all applied stresses, with the observed increase between 2 and 20 times lower when the stress was applied gradually rather than rapidly. The results suggested that the Hsp12p expression rate is a good indicator of applied stress in S. cerevisiae. [source] Glucose-Responsive Bioinorganic Nanohybrid Membrane for Self-Regulated Insulin ReleaseADVANCED FUNCTIONAL MATERIALS, Issue 9 2010Claudia R. Gordijo Abstract A bioinorganic nanohybrid glucose-responsive membrane is developed for self-regulated insulin delivery analogous to a healthy human pancreas. The application of MnO2 nanoparticles as a multifunctional component in a glucose-responsive, protein-based membrane with embedded pH-responsive hydrogel nanoparticles is proposed. The bio-nanohybrid membrane is prepared by crosslinking bovine serum albumin (BSA),MnO2 nanoparticle conjugates with glucose oxidase and catalase in the presence of poly(N -isopropyl acrylamide- co -methacrylic acid) nanoparticles. The preparation and performance of this new nanocomposite material for a glucose-responsive insulin release system is presented. The activity and stability of immobilized glucose oxidase and the morphology and mechanical properties of the membrane are investigated. The enzymatic activity is well preserved in the membranes. The use of MnO2 nanoparticles not only reinforces the mechanical strength and the porous structure of the BSA-based membrane, but enhances the long-term stability of the enzymes. The in vitro release of insulin across the membrane is modulated by changes in glucose concentration mimicking possible fluctuations of blood-glucose level in diabetic patients. A four-fold increase in insulin permeation is observed when the glucose concentration is increased from normal to hyperglycemic levels, which returns to the baseline level when the glucose concentration is reduced to a normal level. [source] Survival of planktonic and sessile Acetobacter cerevisiaeINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 3 2008Clelia Altieri Summary This study was designed to investigate the individual or combined effects of ethanol (4,12%), glucose (10,30%) and acetic acid (0,6%) on survival of planktonic and sessile cells of one strain belonging to the new species Acetobacter cerevisiae isolated from traditional balsamic vinegar. The results confirm that the planktonic cells' survival was negatively affected by ethanol and by acetic acid; moreover, there was a positive correlation between survival and glucose concentration. On the contrary, biofilm formation was observed only in the absence of acetic acid, which was the most affecting variable on the natural ability of cells to attach and grow on surfaces. The obtained results supply new information about the physiology of a novel Acetobacter species and about its natural capability to develop biofilms so that improved control over balsamic vinegar fermentation could be implemented in the future. [source] Amino acid ingestion and glucose metabolism,A reviewIUBMB LIFE, Issue 9 2010Mary C. Gannon Abstract Interest in the effect of proteins or amino acids on glucose metabolism dates back at least a century, largely because it was demonstrated that the amino acids from ingested protein could be converted into glucose. Indeed, these observations influenced the dietary information provided to people with diabetes. Subsequently it was shown that ingested protein did not raise the blood glucose concentration. It also was shown that proteins could stimulate a rise in insulin and glucagon but the response to various proteins was different. In addition, it was shown that individual amino acids also could stimulate a rise in insulin and in glucagon concentrations. When individual amino acids are ingested by normal subjects, there is an ordering of the insulin and glucagon responses. However, the order is not the same for insulin and glucagon. In addition, the metabolic response cannot be predicted based on the functional groups of the amino acids. Thus, empirical prediction of the metabolic response to ingested single amino acids is not possible. © 2010 IUBMB IUBMB Life, 62(9): 660,668, 2010 [source] | |||||||||||||||||||||||||||||||||||||||||||