Factors Associated With Microalbuminuria in 7,549 Children and Adolescents With Type 1 Diabetes in the T1D Exchange Clinic Registry

OBJECTIVE

To examine factors associated with clinical microalbuminuria (MA) diagnosis in children and adolescents in the T1D Exchange clinic registry.

RESEARCH DESIGN AND METHODS

T1D Exchange participants <20 years of age with type 1 diabetes ≥1 year and urinary albumin-to-creatinine ratio (ACR) measured within the prior 2 years were included in the analysis. MA diagnosis required all of the following: 1) a clinical diagnosis of sustained MA or macroalbuminuria, 2) confirmation of MA diagnosis by either the most recent ACR being ≥30 mg/g or current treatment with an ACE inhibitor (ACEI) or angiotensin receptor blocker (ARB), and 3) no known cause for nephropathy other than diabetes. Logistic regression was used to assess factors associated with MA.

RESULTS

MA was present in 329 of 7,549 (4.4%) participants, with a higher frequency associated with longer diabetes duration, higher mean glycosylated hemoglobin (HbA_1c) level, older age, female sex, higher diastolic blood pressure (BP), and lower BMI (P ≤ 0.01 for each in multivariate analysis). Older age was most strongly associated with MA among participants with HbA_1c ≥9.5% (≥80 mmol/mol). MA was uncommon (<2%) among participants with HbA_1c <7.5% (<58 mmol/mol). Of those with MA, only 36% were receiving ACEI/ARB treatment.

CONCLUSIONS

Our results emphasize the importance of good glycemic and BP control, particularly as diabetes duration increases, in order to reduce the risk of nephropathy. Since age and diabetes duration are important nonmodifiable factors associated with MA, the importance of routine screening is underscored to ensure early diagnosis and timely treatment of MA.Elevated urinary albumin excretion is an early sign of diabetic kidney disease (DKD). The American Diabetes Association (ADA) recommends screening for microalbuminuria (MA) annually in people with type 1 diabetes after 10 years of age and 5 years of diabetes duration, with a diagnosis of MA requiring two of three tests to be abnormal (1). Early diagnosis of MA is important because effective treatments exist to limit the progression of DKD (1). However, although reduced rates of MA have been reported over the past few decades in some (2–4) but not all (5,6) studies, it has been suggested that the development of proteinuria has not been prevented but, rather, has been delayed by ∼10 years and that further improvements in care are needed (7).Limited data exist on the frequency of a clinical diagnosis of MA in the pediatric population with type 1 diabetes in the U.S. Our aim was to use the data from the T1D Exchange clinic registry to assess factors associated with MA in 7,549 children and adolescents with type 1 diabetes.     

Extended culturing of androgen-responsive human primary epithelial prostate cell isolates by continuous treatment with interstitial collagenase

Continuous culturing of two distinct human prostate specimens in the presence of interstitial collagenase added directly to conventional medium resulted in the isolation and extended growth of primary epithelial prostate cell (PEPC) cultures from each. Both continued to proliferate substantially beyond the average time determined for analogous untreated epithelial prostate isolates. Both repeatedly stain positive for keratin and are characteristically epithelial in morphological appearance and growth model. Both express androgen receptor mRNA and stain positive for androgen receptors. PEPC-2 displays an androgen dose-dependent stimulation of cell proliferation, as well as specifically binding ³H-R1881. PEPC-1 exhibits a hypotetraploid karyotype with loss of the Y chromosome. PEPC-2 conserves a normal human ploidy, including the Y chromosome, although there is extensive random chromosome loss. Elimination of the collagenase from the medium resulted in decreased cellular proliferation and accumulation of stainable collagen in both PEPC cultures. Neither PEPC isolate produced tumors in male nude mice, whether injected alone, mixed with matrigel, or combined with prostate or bone fibroblastic cells. Prostate 30:7–19, 1997 © 1997 Wiley-Liss, Inc.     

Early epidermal destruction with subsequent epidermal hyperplasia is a unique feature of the papilloma-independent squamous cell carcinoma phenotype in PKCepsilon overexpressing transgenic mice

Protein kinase C epsilon (PKCepsilon) overexpressing transgenic (PKCepsilon Tg) mice develop papilloma-independent squamous cell carcinomas (SCC) elicited by 7,12-dimethylbenz[a]anthracene (DMBA) tumor initiation and 12-O-tetradecanoylphorbol-13-acetate (TPA) tumor promotion. We examined whether epidermal cell turnover kinetics was altered during the development of SCC in PKCepsilon Tg mice. Dorsal skin samples were fixed for histological examination. A single application of TPA resulted in extensive infiltration of polymorphonuclear neutrophils (PMNs) into the epidermis at 24 h after TPA treatment in PKCepsilon Tg mice while wild-type (WT) mouse skin showed focal infiltration by PMNs. Complete epidermal necrosis was observed at 48 h in PKCepsilon Tg mice only; at 72 h, epidermal cell regeneration beginning from hair follicles was observed in PKCepsilon Tg mice. Since the first TPA treatment to DMBA-initiated PKCepsilon Tg mouse skin led to epidermal destruction analogous to skin abrasion, we propose the papilloma-independent phenotype may be explained by death of initiated interfollicular cells originally destined to become papillomas. Epidermal destruction did not occur after multiple doses of TPA, presumably reflecting adaptation of epidermis to chronic TPA treatment. Prolonged hyperplasia in the hair follicle may result in the early neoplastic lesions originally described by Jansen et al. (2001) by expanding initiated cells in the hair follicles resulting in the subsequent development of SCC.     

Characteristics of Streptolysin O Action

A study of the lysis of rabbit erythrocytes by streptolysin O (SO) revealed at least two steps in the hemolytic process. The initial interaction between SO and erythrocytes is the adsorption of the toxin molecule to the cell surface. Adsorption occurred at 4 C and was independent of ionic strength and pH; these results suggest that hydrophobic interactions between SO and the cell may be important in this process. Cholesterol was shown to prevent the adsorption of toxin to the cell, and it is proposed that cholesterol in the red cell membrane may be the site of toxin adsorption. The concept of a lipid attachment site is supported by the findings that proteolytic enzymes and sulfhydryl inhibitors known to affect external erythrocyte proteins did not affect SO hemolysis. Although the number of toxin molecules that will adsorb to a cell is limited, more than one toxin molecule was required for hemolysis. The step(s) following adsorption was dependent on temperature, ionic strength, and pH. Thus, it is evident that this step(s) is readily separable from adsorption, suggesting that an ionic interaction occurs between toxin and an erythrocyte membrane molecule. The step(s) following adsorption was also inhibited by divalent cations. Since N-ethyl maleimide will also inhibit lysis after toxin adsorption, it is possible that divalent cations may prevent SO hemolysis by reacting with free sulfhydryl groups on the toxin molecule.     

Civil defence in a nuclear disaster

Any nuclear war would be horrific and our main aim should be universal abolition of nuclear weapons. Civil defence, with its medical attributes, could certainly increase the survival rate should a disaster occur. The effect of the explosion of a nuclear warhead is outlined, together with what could be done to reduce casualties. Nuclear winter is discussed and it is suggested that the results of computerization of doubtful surmises have been treated too much as proven facts. The possibility of its occurrence should not deter emergency planning. Civil defence can save lives, and the fact that medicine as we know it would cease to exist in an all‐out nuclear war does not excuse us from doing what we can to increase the survival rate, if the worst should happen. Action should therefore be taken now to plan decentralization of resources and to instruct the public in protection, first aid and self‐sufficiency.