Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 11
    ISSN: 1432-0428
    Keywords: Proinsulin ; insulin ; C-peptide ; identical twins ; Type 1 (insulin-dependent) diabetes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Glucose tolerance and insulin secretion were studied in two groups of non-diabetic identical twins of recently-diagnosed Type 1 (insulin-dependent) diabetic patients: (1) a group of 5 twins with islet cell antibodies, and (2) a group of 6 twins without. Despite similar fasting glucose, insulin and C-peptide concentrations both groups of twins had significantly higher fasting proinsulin concentrations than the control group (p〈0.05). The twins with complement-fixing islet cell antibodies had reduced glucose tolerance and clearance, whilst the twins without islet cell antibodies did not. Neither group of twins showed any abnormality in insulin, C-peptide or proinsulin response to oral or intravenous glucose. We conclude that increased fasting proinsulin levels precede abnormalities of insulin secretion, and are an early indication of minor B-cell damage in these twins irrespective of their risk of developing diabetes.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 12
    ISSN: 1432-0428
    Keywords: Impaired glucose tolerance ; pre-diabetes ; insulin-dependent diabetes ; identical twins ; metabolism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Non-diabetic identical twins of insulin-dependent diabetic patients were studied within five years of the diagnosis of their index twin in order to determine whether changes in intermediary metabolism precede the onset of insulin-dependent diabetes mellitus. Two studies were performed: a cross-sectional study of 12 non-diabetic twins and a prospective study of a separate group of 41 non-diabetic twins. Ofthe 12 twins tested in the cross-sectional study six developed insulin-dependent diabetes and six did not; the six who developed diabetes were given an oral glucose load a mean of 10 months before diagnosis; they then had normal fasting blood glucose levels but worse glucose tolerance than control subjects (120 min post-load (mean±SD) blood glucose 8.5±3.5 vs 4.9±0.9 mmol/l respectively, p〈0.05). However, blood lactate, pyruvate, alanine, glycerol, 3-hydroxybutyrate and serum insulin levels were similar. In contrast, the six twins in this cross-sectional study who did not develop diabetes and are now unlikely to do so, as a group, had no significant changes compared with the control subjects though one had impaired glucose tolerance. To determine the predictive value of impaired glucose tolerance a separate group of 41 non-diabetic twins was studied prospectively for 8 to 22 years having a total of 147 glucose tolerance tests in this period; in this group six developed diabetes. Eight of the 41 had impaired glucose tolerance; impaired glucose tolerance was found in four of the six who developed diabetes as compared with only four of the 35 who did not (p〈0.01). Impaired glucose tolerance in these non-diabetic identical twins had a positive predictive value of33% for developing diabetes. The four twins with impaired glucose tolerance who remain nondiabetic now have normal glucose tolerance. We conclude that impaired glucose tolerance may precede the onset of insulin-dependent diabetes mellitus by many months but the change does not specifically predict the disease even in identical twins of diabetic patients. These observations are consistent with the possibility that in some twins the disease process can occur yet remit without leading to diabetes.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 13
    Electronic Resource
    Electronic Resource
    Springer
    Diabetologia 26 (1984), S. 1-5 
    ISSN: 1432-0428
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 14
    ISSN: 1432-0428
    Keywords: Concordance ; identical twins ; Type 1 (insulin-dependent) diabetes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We studied prospectively 49 non-diabetic identical twins of recently-diagnosed Type 1 (insulin-dependent) diabetic patients for up to 24 years (median 9 years). During this time 15 developed Type 1 diabetes. Actuarial analysis indicates that by 12 years 34% of the twins will have developed Type 1 diabetes and that thereafter only another 2% will do so. Inevitable bias in ascertainment of the twins makes it likely that the true figure is less. We conclude that factors which are not genetically determined must be important in the pathogenesis of the disease. The rates of developing Type 1 diabetes in the co-twins declines sharply in the years after diagnosis of the index twin, which suggests that the initiation of the process leading to Type 1 diabetes occurs within a finite, and not a prolonged, period.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 15
    Electronic Resource
    Electronic Resource
    Springer
    Diabetologia 33 (1990), S. 577-577 
    ISSN: 1432-0428
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 16
    ISSN: 1432-0428
    Keywords: Identical twins ; Type 1 (insulin-dependent) diabetes mellitus ; intravenous glucose ; insulin response
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary To define the glucose to insulin dose-response relationship before the onset of diabetes, we studied 22 nondiabetic co-twins of patients with Type 1 (insulin-dependent) diabetes mellitus and nine control subjects. All had intravenous glucose tests at 0.02, 0.1 and 0.5 g/kg and were followedup prospectively for at least 6 years. Seven twins developed diabetes a mean of 7 months later; the remaining 15 are now unlikely to develop diabetes. The seven pre-diabetic twins had higher fasting insulin levels than control subjects (4.2±2.0 vs 1.8±1.8 nmol/l; p〈0.05); but lower glucose clearance (1.0±0.5 vs 1.9±0.7 %/min; p〈0.05), first phase insulin response at 0.5 g/kg (21.1±23.2 vs 143±50 nmol/l; p〈0.0001), and total insulin responses at 0.1 g/kg (p〈0.05) and 0.5 g/kg (p〈0.00005). Using a curve-fitting programme, the normal glucose to insulin relationship was lost in prediabetic twins who had lower coefficient of determination (R2) than control subjects (p〈0.01). In contrast, 15 low-risk twins and their nine control subjects had similar fasting glucose and insulin levels, glucose clearance, R2 and insulin secretory responses to different glucose loads. The positive predictive values of subnormal R2 and subnormal first phase insulin response were 67 % and 58 % respectively. These observations demonstrate an altered glucose to insulin dose-response relationship and loss of maximum insulin secretory response to glucose before the onset of Type 1 diabetes.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 17
    ISSN: 1432-0428
    Keywords: Keywords Type II diabetes mellitus ; actuarial analysis ; concordance rate ; identical twins.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary To determine the concordance rate for Type II (non-insulin-dependent) diabetes mellitus in monozygotic twin pairs, initially ascertained discordant for diabetes, we carried out a prospective study on 44 non-diabetic subjects, each of whom had a sibling twin with diabetes (21 men, 23 women, median age 55 years, interquartile range 47–65). The subjects were referred as discordant for Type II diabetes. The twin pairs were part of the British Diabetic Twin Study and ascertained between May 1968 and January 1998. These subjects underwent an OGTT at time of referral and periodically thereafter. The mean follow-up was 8 years (range 0–18 years) and data were collected until January 1996. The percentage of twins who developed Type II diabetes was assessed by standard actuarial life-table methods and the pairwise concordance rate, that is the proportion of concordant pairs over the sum of concordant and discordant pairs, was calculated. The observed rates of concordance for Type II diabetes at 1, 5, 10, and 15 years follow-up were 17, 33, 57, and 76 %, respectively. The concordance rate for any abnormality of glucose metabolism (either Type II diabetes or impaired glucose tolerance) at 15 years follow-up was 96 %. The concordance rate for Type II diabetes in monozygotic twins is very high even in twins initially ascertained discordant for diabetes. [Diabetologia (1999) 42: 146–150]
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 18
    Electronic Resource
    Electronic Resource
    Springer
    Diabetologia 17 (1979), S. 333-343 
    ISSN: 1432-0428
    Keywords: Genetics ; identical twins ; chlorpropamide alcohol flushing ; retinopathy ; enkephalin ; piqûre ; insulin dependent diabetes ; non-insulin dependent diabetes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Insulin dependent (IDD) and non-insulin dependent diabetes (NIDD) are separate disorders. Twin studies show that IDD cannot be entirely due to genetic causes as concordance is no more than about 50%, but there is some inherited predisposition to it as shown by HLA patterns. NIDD, on the other hand, is predominantly due to genetic causes since identical twins are nearly always concordant. Many cases of NIDD show chlorpropamide alcohol flushing (CPAF), a dominantly inherited feature which may precede the appearance of diabetes and thus act as a genetic marker for this type of diabetes. Diabetics who show chlorpropamide acohol flushing are less likely to develop retinopathy than those who do not. Genetic factors must therefore affect the incidence and severity of diabetic retinopathy. Chlorpropamide alcohol flushing is due to sensitivity to enkephalin. Enkephalin and other opioids affect carbohydrate metabolism and insulin release. It is possible therefore that they act as neurotransmitters and cause NIDD by a sympathetically mediated effect on the liver and pancreas — in other words, that as far as NIDD is concerned Claude Bernard's views on the cause of diabetes may have been right.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 19
    ISSN: 1432-0428
    Keywords: B-cell responses ; i.v. glucose ; i.v. glucagon ; nondiabetic twins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The B-cells of patients with recently diagnosed Type 1 (insulin-dependent) diabetes may have no response to glucose when the response to glucagon is present but attenuated. This observation suggests that the recognition of glucose is more severely affected than that for non-glucose stimulants. To determine whether a similar selective decrease in glucose response was present before the onset of diabetes we studied two groups of non-diabetic identical twins of patients with recently diagnosed Type 1 diabetes: one group with complement-fixing islet cell antibodies who were at high risk of developing diabetes (four of the five have already developed diabetes) and a group without such antibodies at low risk of developing diabetes. In addition, a group of patients with chronic pancreatitis were studied to control for non-specific damage to the B-cell. Responses to i. v. glucose and i.v. glucagon were compared. Patients with chronic pancreatitis has similar responses to both glucose and glucagon and the responses did not differ from control subjects. The B-cells of the immune positive group showed evidence of pathology because the insulin and C-peptide responses to both stimuli were reduced when compared to either their control subjects or the immune negative twin group. However, the B-cell response to both glucose and glucagon in the immune positive twins was similar. Because the B-cell response to glucose was not less than that to glucagon, a selective destruction of the glucose recognition system cannot be a characteristic of all twins throughout the period before they develop Type 1 diabetes.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 20
    ISSN: 1432-1939
    Keywords: Bromus tectorum ; Festuca idahoenis ; Frequency distribution ; Plant populations ; Size hierarchy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The moment skewness coefficient, coefficient of variation and Gini coefficient are contrasted as statistical measures of inequality among members of plant populations. Constructed examples, real data examples, and distributional considerations are used to illustrate pertinent properties of these statistics to assess inequality. All three statistics possess some undesirable properties but these properties are shown to be often unimportant with real data. If the underlying distribution of the variable follows the often assumed two-parameter lognormal model, it is shown that all three statistics are likely to be highly and positively correlated. In contrast, for distributions which are not two-parameter lognormally distributed, and when the distribution is not concentrated near zero, the coefficient of variation and Gini coefficient, which are sensitive to small shifts in the mean, are often of little practical use in ordering the equality of populations. The coefficent of variation is more sensitive to individuals in the right-hand tail of a distribution than is the Gini coefficient. Therefore, the coefficient of variation may often be recommended over the Gini coefficient if a measure of relative precision is selected to assess inequality. The skewness coeficient is suggested when the distribution is either three-parameter lognormally distributed (or close to such), or when a measure of relative precision is not indicated.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...