Coated-platelet levels in patients with Type 1 and with Type 2 diabetes mellitus

Coated-platelet levels were quantified in 58 people with Type 1 diabetes, 90 with Type 2 diabetes, and 54 non-diabetic controls. In diabetes high coated-platelet levels were related to smoking and glucose control drugs, but not to glycaemia or other drugs. Prospective studies should evaluate coated-platelets and complications and drug effects.

Effect of intensive glycemic control on levels of markers of inflammation in type 1 diabetes mellitus in the diabetes control and complications trial

Type 1 diabetes mellitus is associated with an increased risk of cardiovascular disease (CVD) that is not fully explained by conventional risk factors. The Diabetes Control and Complications Trial (DCCT) showed that intensive diabetes therapy reduced levels of LDL cholesterol and triglycerides but increased the risk of major weight gain, which might adversely affect CVD risk. The present study examined the effect of intensive therapy on levels of several markers of inflammation that have been linked to risk of CVD.

Maillard reaction products and their relation to complications in insulin-dependent diabetes mellitus

Glycation, oxidation, and browning of proteins have all been implicated in the development of diabetic complications. We measured the initial Amadori adduct, fructoselysine (FL); two Maillard products, N epsilon-(carboxymethyl) lysine (CML) and pentosidine; and fluorescence (excitation = 328 nm, emission = 378 nm) in skin collagen from 39 type 1 diabetic patients (aged 41.5 +/- 15.3 [17-73] yr; duration of diabetes 17.9 +/- 11.5 [0-46] yr, [mean +/- SD, range]). The measurements were related to the presence of background (n = 9) or proliferative (n = 16) retinopathy; early nephropathy (24-h albumin excretion rate [AER24] > or = 20 micrograms/min; n = 9); and limited joint mobility (LJM; n = 20). FL, CML, pentosidine, and fluorescence increased progressively across diabetic retinopathy (P <0.05, P <0.001, P <0.05, P <0.01, respectively). FL, CML, pentosidine, and fluorescence were also elevated in patients with early nephropathy (P <0.05, P <0.001, P <0.01, P <0.01, respectively). There was no association with LJM. Controlling for age, sex, and duration of diabetes using logistic regression, FL and CML were independently associated with retinopathy (FL odds ratio (OR) = 1.06, 95% confidence interval (CI) = 1.01-1.12, P <0.05; CML OR = 6.77, 95% CI = 1.33-34.56, P <0.05) and with early nephropathy (FL OR = 1.05, 95% CI = 1.01-1.10, P <0.05; CML OR = 13.44, 95% CI = 2.00-93.30, P <0.01). The associations between fluorescence and retinopathy and between pentosidine and nephropathy approached significance (P = 0.05). These data show that FL and Maillard products in skin correlate with functional abnormalities in other tissues and suggest that protein glycation and oxidation (glycoxidation) may be implicated in the development of diabetic retinopathy and early nephropathy.

Decrease in skin collagen glycation with improved glycemic control in patients with insulin-dependent diabetes mellitus

Glycation, oxidation, and nonenzymatic browning of protein have all been implicated in the development of diabetic complications. The initial product of glycation of protein, fructoselysine (FL), undergoes further reactions, yielding a complex mixture of browning products, including the fluorescent lysine-arginine cross-link, pentosidine. Alternatively, FL may be cleaved oxidatively to form N(epsilon)-(carboxymethyl)lysine (CML), while glycated hydroxylysine, an amino-acid unique to collagen, may yield N(epsilon)-(carboxymethyl)hydroxylysine (CMhL). We have measured FL, pentosidine, fluorescence (excitation = 328 nm, emission = 378 nm), CML, and CMhL in insoluble skin collagen from 14 insulin-dependent diabetic patients before and after a 4-mo period of intensive therapy to improve glycemic control. Mean home blood glucose fell from 8.7 +/- 2.5 (mean +/- 1 SD) to 6.8 +/- 1.4 mM (P less than 0.005), and mean glycated hemoglobin (HbA1) from 11.6 +/- 2.3% to 8.3 +/- 1.1% (P less than 0.001). These changes were accompanied by a significant decrease in glycation of skin collagen, from 13.2 +/- 4.3 to 10.6 +/- 2.3 mmol FL/mol lysine (P less than 0.002). However, levels of browning and oxidation products (pentosidine, CML, and CMhL) and fluorescence were unchanged. These results show that the glycation of long-lived proteins can be decreased by improved glycemic control, but suggest that once cumulative damage to collagen by browning and oxidation reactions has occurred, it may not be readily reversed. Thus, in diabetic patients, institution and maintenance of good glycemic control at any time could potentially limit the extent of subsequent long-term damage to proteins by glycation and oxidation reactions.

Non-enzymatic glycosylation of skin collagen in patients with type 1 (insulin-dependent) diabetes mellitus and limited joint mobility

Forearm skin biopsies were obtained from diabetic subjects with and without limited joint mobility, and from non-diabetic control subjects. Collagen purified from these samples was assayed for non-enzymatic glycosylation. The level in all diabetic patients was significantly greater than that in control subjects (p less than 0.001), but those diabetic patients with limited joint mobility had a level of collagen glycosylation similar to that in those with normal joints (15.3 +/- 1.3 and 16.5 +/- 1.3 nmol fructose/10 mg protein, respectively; mean +/- SEM). Glycosylation of collagen in the diabetic patients correlated with glycosylated haemoglobin measured at the time of skin biopsy (r = 0.60). These results do not support the hypothesis that non-enzymatic glycosylation of collagen, as reflected by the ketoamine link, plays an important role in the development of limited joint mobility in diabetes.

Predicting the need for insulin therapy in late onset (40-69 years) diabetes mellitus

A six-year prospective study of 144 newly diagnosed, symptomatic diabetic patients aged 40-69 years showed that 21 (15%) required insulin therapy, commencing 1-61 months after diagnosis. The plasma insulin response to oral glucose was assessed at the time of diagnosis. All 12 patients with very low peak insulin response (less than or equal to 6 mU/l) required insulin therapy. Thirty-six patients had an intermediate insulin response (greater than 6 less than or equal to 18 mU/l); of these, 7 with a mean weight 88% (range 73-96%) of average body weight required insulin, while 29 with a mean weight 117% (range 98-158%) of average body weight, did not. Ninety-six patients had a peak insulin response (greater than 18 mU/l); 2 patients whose weights were 96% and 100% of average body weight, required insulin, while the remainder did not. Consideration of initial body weight and peak insulin response provides a useful prediction of the eventual need for insulin.

Multimodal functional and anatomical imaging identifies preclinical microvascular abnormalities in type 1 diabetes mellitus

Structural and functional change in the microcirculation in type 1 diabetes mellitus predicts future end-organ damage and macrovascular events. We explored the utility of novel signal processing techniques to detect and track change in ocular hemodynamics in patients with this disease. 24 patients with uncomplicated type 1 diabetes mellitus, and 18 age-and-sex matched control subjects were studied. Doppler ultrasound was used to interrogate the carotid and ophthalmic arteries and digital photography to image the retinal vasculature. Frequency analysis algorithms were applied to quantify velocity waveform structure and retinal photographic data at baseline and following inhalation of 100% oxygen. Frequency data was compared between groups. No significant differences were found in the resistive index between groups at baseline or following inhaled oxygen. Frequency analysis of the Doppler flow velocity waveforms identified significant differences in bands 3-7 between patients and controls in data captured from the ophthalmic artery (p<0.01 for each band). In response to inhaled oxygen, changes in the frequency band amplitudes were significantly greater in control subjects compared with patients (p<0.05). Only control subjects demonstrated a positive correlation (R=0.61) between change in retinal vessel diameter and frequency band amplitudes derived from ophthalmic artery waveform data. The use of multimodal signal processing techniques applied to Doppler flow velocity waveforms and retinal photographic data identified preclinical change in the ocular microcirculation in patients with uncomplicated diabetes mellitus. An impaired autoregulatory response of the retinal microvasculature may contribute to the future development of retinopathy in such patients.

A children's nurse's role in the global development of a child with diabetes mellitus.

The nursing care of a six year old with type 1 diabetes reveals the importance of accurate control of the condition for normal physical, emotional and cognitive development. Clearly the children's nurse can educate and support the child, parents and extended family towards achieving independence and self-care. Theoretical knowledge of normal child maturation can guide nurses to constantly adapt their modes of communication and nursing skills, so as to promote every aspect and stage of the child's growth. Prevalence of type 1 diabetes is increasing, and nurses should use their close professional involvement with patients to assist research at every opportunity.

A cross-sectional study demonstrating increased serum amyloid A-related inflammation in high density lipoproteins from subjects with type 1 diabetes mellitus and how this association was augmented by poor glycaemic control

Inflammatory atherosclerosis is increased in subjects with type 1 diabetes mellitus (T1DM). Normally high-density lipoproteins(HDL) protect against atherosclerosis; however, in the presence of serum amyloid-A- (SAA-) related inflammation this propertymay be reduced. Fasting blood was obtained from fifty subjects with T1DM, together with fifty age, gender and BMI matchedcontrol subjects. HDL was subfractionated into HDL2 and HDL3 by rapid ultracentrifugation. Serum-hsCRP and serum-, HDL2-,and HDL3-SAA were measured by ELISAs. Compared to control subjects, SAA was increased in T1DM subjects, nonsignificantly inserum (P = 0.088), and significantly in HDL2 (P  = 0.003) and HDL3 (P  = 0.005). When the T1DM group were separated accordingto mean HbA1c (8.34%), serum-SAA and HDL3-SAA levels were higher in the T1DM subjects with HbA1c ≥ 8.34%, compared towhen HbA1c was <8.34% (P  < 0.05). Furthermore, regression analysis illustrated, that for every 1%-unit increase in HbA1c, SAAincreased by 20% and 23% in HDL2 and HDL3, respectively, independent of BMI. HsCRP did not differ between groups (P  > 0.05).This cross-sectional study demonstrated increased SAA-related inflammation in subjects with T1DM that was augmented by poorglycaemic control. We suggest that SAA is a useful inflammatory biomarker in T1DM, which may contribute to their increasedatherosclerosis risk.