bluuebunny/crossref_metadata_2025 huggingface dataset:
Kidney-Graft Survival in Simultaneous Kidney-Pancreas Transplantation
Authors: LeFrancois Nicole , Faure Jean Louis , Melandri Marco , Sanseverino Roberto , Martin Xavier , Camozzi Luca , Betuel Hervé , Gelet Albert , Touraine Jean Louis , Dubernard Jean Michel
Published: September 2013

Patient and kidney survival rates were compared between 69 diabetic patients undergoing simultaneous kidney-pancreas transplantation (group 1) and 723 nondiabetic patients undergoing kidney transplantation (group 2). The patients were treated with different immunosuppressive regimens over the years: steroids plus antilymphocyte globulin (ALG) plus azathioprine (Aza); cyclosporin A (CsA) plus ALG; steroids plus ALG plus Aza, replacing Aza 1 mo posttransplantation; or low doses of steroids plus CsA plus Aza. One-year kidney survival rates with the different regimens were 50, 42, 54, and 76%, respectively, in group 1 and 71, 74, 78, and 84%, respectively, in group 2. Patient survival was 60, 57, 71, and 86%, respectively, in group 1 and 93, 95, 94, and 96%, respectively, in group 2. Differences between the two groups were statistically significant for the first three protocols but not for the one used in this study. In group 1,38 patients (55%) had a functioning kidney graft, whereas 15 (21%) lost their kidney to rejection. Between these two patient categories, there was no significant difference in age, sex, duration of diabetes, time on dialysis, blood transfusion number, HLA immunization, or HLA matching. Thus, since 1984, kidney-graft survival has not been inferior in diabetic patients. This improvement is mainly due to a decreased mortality related to better patient preparation and improvement in immunosuppression.
Method for Home Monitoring of Urinary Amylase After Pancreas Transplantation
Authors: Prieto Mikel , Collins Wayne , Scott Michael H , Sells Robert A
Published: September 2013

Urinary amylase activity (UAA) is used for diagnosis of rejection in bladder-drained pancreas grafts. Unfortunately, most rejection episodes occur after the patient has been discharged. In those cases, an early diagnosis is often difficult, and a method for home UAA monitoring is needed. We have developed a method that can be used for this purpose. The method, based on Kodak dry-film technology, is shown to have good response to the wide range of UAA seen in these patients compared with responses to standard laboratory kinetic methods. The analysis (performed by the patient) involves 1) collecting urine for 24 h in a 4-L container, 2) diluting the urine with tap water to a total urine of 4 L, and 3) placing a drop of this dilution onto a slide. The slide is read by a handheld spectrophotometer that displays the UAA in secreted units per hour. The reliability of this system has been tested for wide changes of urine pH, volume of the drop applied to the slide, and tap water from different sources. Temperature coefficients have been determined to correct changes in ambient temperatures. The final handheld prototype is being developed based on these preliminary studies. This device could be of benefit for the early diagnosis of rejection episodes in recipients of bladder-drained pancreas grafts after hospital discharge.
Rejection of Kidney and Pancreas After Pancreas-Kidney Transplantation
Authors: Margreiter Raimund , Klima Günther , Bösmüller Claudia , Königsrainer Alfred , Schmid Thomas , Steiner Ekkehard
Published: September 2013

On the basis of 26 combined pancreas-kidney transplants we questioned whether both organs undergo rejection simultaneously. Reliable diagnosis of pancreas-graft rejection was made possible by monitoring exocrine graft function, including quantitative measurements of pancreatic juice, its amylase content, and pancreatic juice cytology. In addition, diagnosis of pancreas rejection was based on regular flow studies, daily urinary neopterin excretion, and a retrospective analysis of the clinical course. Clinical symptoms, blood chemistry, and, primarily, histology were used to assess rejection of the kidney allograft. In 18 cases the kidney and pancreas were rejected together; in 8 cases the kidney or the pancreas was rejected. Although both organs were rejected at the same time in most cases, either organ can be rejected alone. Thus, the kidney cannot be used to monitor the pancreas allograft in every case.
Mechanism of IGF-I-Stimulated Glucose Transport in Human Adipocytes: Demonstration of Specific IGF-I Receptors Not Involved in Stimulation of Glucose Transport
Authors: Sinha Madhur K , Buchanan Cresada , Leggett Nancy , Martin Lourdes , Khazanie Prabhaker G , Dimarchi Richard , Pories Walter J , Caro José F
Published: September 2013

We demonstrate the presence of specific insulinlike growth factor I (IGF-I) receptors in human adipocytes. Competition studies with 125I-labeled IGF-I and unlabeled IGF-I, IGF-II, and insulin showed the specificity of 125I-IGF-I binding to the IGF-I receptors in adipocytes, membranes, and partially purified detergent-solubilized extracts. The monoclonal antibody to the IGF-I receptor (α-IR3) inhibits 125I-IGF-I binding and immunoprecipitates the IGF-I receptor. In addition, the α-subunit of IGF-I receptor is ∼10,000 Mr larger than the α-subunit of insulin receptor, and IGF-I stimulates phosphorylation of the β-subunit of the IGF-I receptor. IGF-I stimulates basal glucose transport in human adipocytes, but the concentrations of IGF-I required for half-maximal and maximal stimulation of glucose transport are 800- and 1000-fold greater than that of insulin. The possibility of IGF-I stimulating glucose transport by interacting predominantly with insulin receptors is suggested by data showing that 1) IGF-I competes with insulin-binding sites, 2) there is a lack of an additive effect with IGF-I and insulin in stimulating glucose transport, 3) α-IR3, which specifically inhibits IGF-I binding, does not inhibit IGF-I or insulin-stimulated glucose transport, 4) insulinreceptor antibody MA-10 inhibits IGF-I and insulinstimulated glucose transport, and 5) IGF-I stimulates insulin-receptor autophosphorylation, although its effect is markedly decreased compared with insulin. In summary, human adipocytes possess specific IGF-I receptors. However, IGF-I stimulates glucose transport predominantly by interacting with the insulin receptor.
Comparison of Insulin Autoantibodies in Diabetes-Related and Healthy Populations by Precise Displacement ELISA
Authors: Dean Betty M , McNally Jessica M , Bonifacio Ezio , Jennings Adrian M , Dunger David B , Gale Edwin A M , Bottazzo Gian Franco
Published: September 2013

The second international workshop on insulin autoantibodies (IAAs) demonstrated improved concordance among laboratories with both radioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA) when measurements were based on signals displaceable by preincubation with excess insulin. This feature has been incorporated into our original ELISA for IAAs, and the assay was used to compare IAAs in diabetes-related and healthy populations. The serum from a healthy islet cell antibody (ICA)+ and IAA+ subject was used to construct standard curves with and without preincubation with 1 U/ml human insulin. Reporting results in arbitrary displacement (Δ ± IAA) units derived from the standard curve improved precision and increased the specificity of the assay. Frequency analysis of the results from 200 control adults did not show a normal distribution, and cumulative frequency analysis demonstrated two populations: 10 of 200 (5%) control adults, 8 of 241 (3.3%) healthy schoolchildren, and 18 of 229 (7.9%) non-insulin-dependent diabetes mellitus (NIDDM) patients had IAAs >12 Δ ± IAA units. On the same basis, we tested samples from 89 individuals in the prospective Bart's Windsor Family Study for insulin-dependent diabetes mellitus (IDDM), 31 of whom had ICAs >5 Juvenile Diabetes Foundation (JDF) units. Of those with ICAs >5 JDF units, 12 developed IDDM and 1 developed NIDDM in 10 yr of study. IAAs >12 Δ ± IAA units were found in 6 of 12 (50%) who became diabetic and in 4 of 18 (22%) who remain healthy. A significant association of IgG IAAs with ICAs >5 JDF units is confirmed in this IDDM-susceptible cohort (P < .0005) but was not observed in the other groups studied. The predictive value of a positive test with IgG IAAs alone is poor (20%), but the combined positive predictive value of both markers conjointly for IDDM is 60%, and the predictive value for health is 98.7%. We suggest that screening for IAAs by ELISA should be restricted to those with ICAs >5 JDF units.
Influence of Maternal Dietary Zn Intake on Expression of Diabetes-Induced Teratogenicity in Rats
Authors: Uriu-Hare Janet Y , Stern Judith S , Keen Carl L
Published: September 2013

Diabetic rat pregnancies are characterized by altered maternal and fetal Zn metabolism and a higher frequency of fetal malformations. In this study, the effect of varying maternal dietary Zn on pregnancy and fetal outcome and on maternal and fetal trace element status were investigated. Starting on day 0 of gestation, streptozocin-induced diabetic andondiabetic control rats were fed a low-Zn diet (4.5 (μg/g diet), an adequate-Zn diet (24.5 μg/g diet), or a high-Zn diet (500 μg/g diet) throughout gestation. Fetuses were taken by cesarean section on gestation day 20. Fetuses from diabetic dams were smaller, weighed less, and had less calcified skeletons and more malformations than fetuses from control dams. In the controls, maternal dietary Zn had a minor effect on fetal malformation frequency. In contrast, in the diabetic animals, the low-Zn diet had a strong teratogenic effect. In diabetic dams, the adequate- and high-Zn diets improved fetal length and weight more than it did in fetuses from nondiabetic dams. However, supplemental dietary Zn during diabetic pregnancy did not further improve malformation frequencies. Liver and kidney Zn, Cu, and metallothionein concentrations were higher in diabetic dams than in control dams. In contrast, liver Zn, Cu, and metallothionein concentrations in fetuses of diabetic dams were lower than in fetuses from control dams, regardless of maternal dietary Zn intake. These results show that diabetes during pregnancy can amplify the teratogenic effects of a mild maternal Zn deficiency. The results also suggest that the diabetic condition alters Zn and Cu transport across diabetic placentas and/or alters Zn and Cu retention of fetuses from diabetic versus control dams, despite differing levels of maternal dietary Zn intake.
Comparison of High— and Low—Diabetes-Incidence NOD Mouse Strains
Authors: Baxter Alan G , Adams Mark A , Mandel Thomas E
Published: September 2013

The nonobese diabetic (NOD) mouse is a model of insulin-dependent diabetes mellitus. These mice develop insulinopenia and hyperglycemia secondary to α-cell destruction, which is associated with insulitis and autoantibody production. We have two strains of NOD mice: a low-incidence strain (NOD/Wehi), in which <10% females and <1% males develop diabetes by 150 days despite intense insulitis, and a highincidence strain (NOD/Lt), in which most females and many males develop diabetes by 150 days. This phenotypic difference has been maintained for 24 mo despite identical housing in our specific pathogenfree unit. Reciprocal skin grafting and allozyme electrophoresis have not identified a difference between the strains. Mixed-lymphocyte cultures were performed with splenic T-lymphocytes cultured with equal numbers of irradiated stimulator splenocytes for 3–6 days. NOD/Wehi mice demonstrated a heightened syngeneic mixed-lymphocyte response (SMLR), averaging 19% of the allogeneic response to CBA/CaHWehi cells. The response to NOD/Lt stimulator cells was not significantly different from the syngeneic response. In contrast, NOD/Lt mice had an SMLR similar to that of BALB/cAnBradleyWehi control mice, averaging 5% of the allogeneic response. NOD/Lt cells also responded similarly to NOD/Wehi stimulator cells and briskly to allogeneic cells. The heightened SMLR in NOD/Wehi mice may reflect active generation of suppressor function, and this may account for the low incidence of diabetes.
Life-Table Analysis of Progression to Diabetes of Anti-Insulin Autoantibody-Positive Relatives of Individuals With Type I Diabetes
Authors: Ziegler Anette G , Ziegler Ralph , Vardi Pnina , Jackson Richard A , Soeldner J Stuart , Eisenbarth George S
Published: September 2013

Cytoplasmic islet cell antibody–negative (ICA−; <20 Juvenile Diabetes Foundation units, n = 1670) and ICA+ (n = 42) first-degree relatives of type I (insulindependent) diabetic individuals were studied for competitive insulin autoantibodies (ClAAs) with a radioassay. Overall, 3.7% of first-degree relatives (64 of 1712) were CIAA+. Of ICA− relatives, 2.7% (45 of 1670) exceeded the upper limit of our normal CIAA range (>39 nU/ml), and 45% (19 of 42) of ICA+ relatives exceeded this normal range. Follow-up serums for repeat CIAA determination have been obtained from 16 of the nondiabetic CIAA/ICA individuals (time between samples, 0.4–5.8 yr). Fourteen of these 16 (87%) CIAA/ICA relatives were found to still be positive on follow-up, and 2 of the relatives who were positive on the first determination were negative on their follow-up test. With a mean follow-up of ∼2 yr, 4 of 45 (9%) of the CIAA+/ICA-relatives, 5 of 23 (22%) of the ICA/CIAA-relatives, and 12 of 19 (63%) of the CIAA+/ICA+ relatives developed diabetes. Life-table analysis indicated that, overall, 53% of CIAA+ relatives become diabetic after 5 yr of follow-up versus 65% of ICA+ relatives. Also by life-table analysis, the predicted risk after 5 yr of follow-up for progression to diabetes is 17% for CIAA+/ICA− relatives, 42% for ICA+/CIAA− relatives, and 77% for CIAA/ICA+ relatives. The highest rate of progression to diabetes was found in ICA+ relatives with CIAA levels >150 nU/ml (100% projected to be diabetic within 5 yr, P < .008 vs. ICA/CIAA relatives).
High-Glucose Stimulation of 64,000-Mr Islet Cell Autoantigen Expression
Authors: Kämpe Olle , Andersson Arne , Björk Elisabeth , Hallberg Anders , Karlsson F Anders
Published: September 2013

This study examined the effect of various extracellular glucose concentrations on the expression of a previously described 64,000-Mr islet cell autoantigen associated with insulin-dependent diabetes mellitus. The protein was precipitated from patient serums incubated with Triton X-100 lysates of [35S]methioninelabeled rat pancreatic islets that had been cultured in 5, 11, or 28 mM glucose for 6 h or 3 days. In both types of experiment, 28 mM glucose was the most efficient stimulator of 64,000-Mr autoantigen production. In contrast, the class I antigens of the major histocompatibility complex, precipitated by a rabbit polyclonal antiserum, were not influenced by differences in glucose concentrations. Our data indicate that expression of islet cell antigens may be increased during the course of hyperglycemia and suggest that the functional activity of islet cells influences their antigenicity.
Macrophage-Mediated Islet Cell Cytotoxicity in BB Rats
Authors: Nagy M Varsanyi , Chan Eve K , Teruya Masanori , Forrest Luette E , Likhite Vilas , Charles M Arthur
Published: September 2013

Islet cell killing mediated by natural killer cells and T-lymphocytes in diabetes-prone (DP) and diabetic BB rats has been described, but other killing mechanisms may also be involved. Histopathologic studies suggest that macrophages are the first immune cells to infiltrate islets. To determine if macrophages are the first cells mediating islet damage, macrophagemediated cytotoxicity was evaluated in BB rats of different ages. Splenic macrophages isolated from DP rats at 33,100,120, and 140 days of age showed no enhanced islet killing compared with diabetes-resistant rats. Killing at diabetes onset (121 ± 14 days) was markedly increased (43 ± 9.3%) compared with agematched diabetes-resistant controls (19 ± 8.3%, P < .001). Islet inflammation was monitored at all time points. At 120 and 140 days of age, 9 of 11 (82%) DP rats had insulitis, and cytotoxicity was increased in 6 of 11 (55%) rats, which is similar to the number of DP rats that progress to diabetes. At 100 days, 3 of 6 (50%) DP rats again showed diabetic levels of killing, even in the absence of insulitis. These data indicate that 1) islet inflammation is dissociated from clinical diabetes onset, 2) splenic macrophages may have islet-killing potential before islet inflammation, 3) macrophage-mediated islet killing is elevated in all animals immediately after diabetes onset, and 4) macrophages, in addition to natural killer cells and T-lymphocytes, are responsible for cell-mediated islet destruction and thus are candidates for the first cellular effector to result in islet killing.
Functional and Morphological Aspects of Impaired TRH Release by Mediobasal Hypothalamus of STZ-Induced Diabetic Rats
Authors: Bestetti Gilberto E , Reymond Marianne J , Boujon Claude E , Lemarchand-Béraud Therèse , Rossi Giovanni L
Published: September 2013

Streptozocin-induced diabetes (STZ-D) in rats is associated with marked hypothyroidism characterized by functional impairment and structural lesions of the pituitary-thyroid axis. Degenerative axonal lesions, which can be prevented by insulin administration, have been reported in the mediobasal hypothalamus (MBH) of STZ-D rats. However, direct evidence connecting anatomic MBH lesions with functional impairment is still missing. We therefore performed a combined functional and morphological investigation in 4-mo-old STZ-D male rats (diabetes lasted 1 mo), applying an in vitro model to study in the same isolated MBH 1) the basal and depolarization-induced thyrotropin-releasing hormone (TRH) release during two successive incubations of 20 min each and 2) morphological and morphometric aspects, including distribution and amount (densitometric evaluation) of immunoreactive TRH in the incubated tissue. In basal conditions, TRH release was much lower in diabetic than control MBH during both incubations (P < .01 vs. P < .05). In depolarizing conditions, TRH release was increased during the second incubation in control (P < .05) and during both incubations in diabetic (P < .01) rats, the percentage increase of the TRH release due to ionic stimulation being much higher in diabetic than control animals (P < .01). As determined by light-microscope morphometry, the total area of dilated-axon cross sections was larger in diabetic than control MBH under basal conditions (P < .01), thus confirming degenerative axonopathy in diabetic rats. By densitometry determination, the amount of immunoreactive TRH was higher in stimulated diabetic MBH compared with both stimulated control and basal diabetic MBH (P < .01). The total area of immunoreactive TRH was increased in stimulated diabetic MBH (P < .05). Our findings show impaired in vitro TRH secretion without reduced TRH content in diabetic MBH. This should play an important role in the pathogenesis of the pituitary and thyroid lesions responsible for the hypothyroidism observed in STZ-D rats.
Combined Effect of Growth Hormone and Cortisol on Late Posthypoglycemic Insulin Resistance in Humans
Authors: Fowelin Jesper , Attvall Stig , Schenck Henning Von , Smith Ulf , Lager Ibe
Published: September 2013

The occurrence and mechanisms for late (6.5- to 7.5-h) posthypoglycemic insulin resistance were studied with the euglycemic clamp in 19 healthy subjects. Comparisons were made with a control study with the same insulin infusion rate but where hypoglycemia was prevented by glucose infusion. Glucose production and utilization were studied with D-[3-3H] glucose infusions. Hypoglycemia induced marked insulin resistance shown by lower glucose infusion rates compared with the control study 3.1 ± 0.3 vs. 6.0 ± 0.7 mg · kg−1 · min−1 P < .001). This late posthypoglycemic insulin resistance was mainly due to a decreased insulin effect on glucose utilization. Infusion of propranolol did not prevent insulin resistance, whereas somatostatin partially prevented its appearance. Somatostatin plus metyrapone completely normalized posthypoglycemic insulin resistance. A positive correlation (r = .72, P < .001) was found between initial insulin sensitivity and percent reduction of the insulin effect after hypoglycemia. Thus, hypoglycemia is followed by prolonged (6- to 8-h) insulin resistance. In contrast to early-phase (2- to 3-h) resistance, long-term resistance is not due to β-adrenergic stimulation but to the combined effect of growth hormone and cortisol. This resistance is also more pronounced in subjects with initially high insulin sensitivity.
Insulin Release in RINm5F Cells and Glyceraldehyde Activation of Protein Kinase C
Authors: Thomas Thomas P , Ellis Thomas R , Pek Sumer Belbez
Published: September 2013

In the insulin-secreting, glucose-insensitive islet cell subclone RINm5F, the distribution of protein kinase C (PKC) activity in the cytosol and membrane fractions was determined, and the activation of the enzyme, as reflected in its translocation to the membrane fraction, was characterized in conjunction with insulin release. DL-Glyceraldehyde (15 mM) evoked a rapid redistribution of PKC from the cytosol to the membrane fraction; insulin release increased concomitantly. When monitored over 5 min with 15 mM glyceraldehyde, membrane stabilization of PKC reached a maximum at 30 s and decreased thereafter; insulin release occurred at a high rate for the first 15 s and diminished thereafter. With 2–20 mM glyceraldehyde, a dose-dependent increase in membrane stabilization of PKC occurred and was accompanied by a matching increase in insulin release. Exogenous 1,2-dioctanoyl-sn-glycerol (100 μM) induced a rapid membrane stabilization of PKC and concomitant stimulation of insulin release. Glucose (15 mM) failed to evoke any redistribution of PKC or release of insulin. Depletion of total PKC activity by 95% induced by 18-h incubations with 2 μM 12-O-tetradecanoylphorbol-13-acetate resulted in a 67–91% reduction in glyceraldehyde-induced insulin release. We conclude that in the RINm5F islet β-cell subclone 7) the rapid activation of PKC, which occurs in response to the administration of glyceraldehyde, a nutrient secretagogue, plays an amplifying role in the initiation of stimulated insulin release; and 2) the failure of the activation of PKC may be responsible for the insensitivity to glucose.
Content of Adenine Nucleotide Translocator mRNA in Insulin-Producing Cells of Different Functional States
Authors: Welsh Nils , Svensson Carina , Welsh Michael
Published: September 2013

This study was undertaken to characterize the expression of the gene coding for the adenine nucleotide translocator (ANT) in the insulin-producing β-cell and to study any possible relationship between its expression and the functional state of the β-cell. Adult and fetal rat pancreatic islets were prepared and cultured under different conditions in vitro. The total RNA from these islets and from the insulin-producing RINm5F cells was isolated and analyzed by the Northern blot technique via a cDNA clone (pAAC-9) coding for the bovine ANT. We found that a 1600-base pair (bp) mRNA hybridizing to the pAAC-9 clone could be detected in RINm5F cells, and a 1450-bp mRNA was similarly observed in the islets. These sizes correspond well to previously reported forms of mRNA for the ANT observed in other tissues. When comparing the intensities of the pAAC-9 hybridizing bands of the different islet groups, it was observed that fetal islets contained less of this mRNA than adult islets. Furthermore, the content of the ANT mRNA in adult islets cultured at a high glucose concentration was increased compared with islets cultured at a low glucose concentration. Finally, streptozocin-treated islets, which display an impaired glucose-sensitive insulin release after 6 days in culture, also contained less of this mRNA than the control islets. We conclude that pancreatic islet cells express an mRNA that appears to be highly homologous to the bovine ANT and that the contents of this mRNA increases with the functional status of the β-cell. It is furthermore suggested that defects in the expression of this gene may be associated with impaired glucose sensitivity.
Effects of Streptozocin-Induced Diabetes on Sympathetic and Parasympathetic Stimulation of Parotid Salivary Gland Function in Rats
Authors: Anderson Leigh C , Garrett John R , Thulin Anders , Proctor Gordon B
Published: September 2013

Diabetes was induced with streptozocin in male Wistar rats. After 4–6 mo, parotid salivary flow was induced by stimulating bipolar electrodes (3–5 V for 2 ms) on either the auriculotemporal nerve (5 Hz) or the cervical sympathetic trunk (10 Hz). During parasympathetic stimulation, flow rates were 443 ± 287 μl/30 min in diabetic animals compared to 657 ± 134 μl/30 min in controls (P < .01). Although parotid flow rates during parasympathetic stimulation were well maintained in controls, they decreased rapidly in most diabetic rats. Parotid secretory response to sympathetic stimulation was also reduced in diabetic compared with control animals (40 ± 16 μl/30 min and 82 ± 50 μl/30 min, respectively, P < .01). In contrast to results obtained with direct neural stimulation, no differences in threshold dose or total saliva were observed when cholinergic (methacholine) and peptidergic (physalaemin) agonists were administered intravenously. Response threshold for an adrenergic agonist (epinephrine) was significantly increased in diabetes. Electron microscopy showed axoplasmic abnormalities in nonmyelinated axons in diabetic glands but not in control glands. Although most nerve profiles appeared normal, neuroaxonal abnormalities were found in every diabetic animal. The ultrastructural findings and the similar responses to methacholine and physalaemin suggest that autonomie neuropathy may be a factor in the abnormal response of the parotid gland to parasympathetic nerve stimulation.
Abnormal T-Lymphocyte Subsets in Type I Diabetes
Authors: Faustman Denise , Eisenbarth George , Daley John , Breitmeyer James
Published: September 2013

Type I (insulin-dependent) diabetes mellitus is a slow autoimmune disease associated with the selective destruction of β-cells in the islets of Langerhans. Recent studies in humans indicate that autoantibodies to insulin and islets of Langerhans appear years before overt diabetes and identify a normoglycemic prediabetic state. To determine whether type I diabetes mellitus represents a generalized immunologic disorder, we studied the phenotypic characteristics of peripheral blood lymphocytes from all stages, i.e., prediabetic, new-onset diabetic, and long-term diabetic patients, with the anti-2H4 monoclonal antibody CD45R, which defines a human suppressor-inducer subset, and the anti-4B4 monoclonal antibody CDw29, which defines a human helper-inducer subset of peripheral blood lymphocytes. All 22 prediabetic patients had elevated T4+2H4+ (suppressor-inducer) cells and reciprocal depressed T4+4B4+ (helper-inducer) cells compared with healthy age-matched control subjects. In addition, the T4/T8 ratio in prediabetic patients was decreased compared with the age-matched control subjects. The abnormal T4+2H4+ and T4+4B4+ subsets were resolved in 20 new-onset and 15 long-term diabetic patients. Family studies showed that the changes in the 2H4 and 4B4 antigens were not part of an inherited polymorphic determinant, because these markers were normal in unaffected siblings and parents. Ten prediabetic patients were restudied >1 yr after the original analysis and showed the persistence of the observed changes. This abnormal increase in suppressor-inducer cells and decrease in helper-inducer cells among islet and insulin antibody-positive prediabetic patients may be of help in understanding diabetes pathogenesis and may also be an early noninvasive screening tool for the detection of the prediabetic state.
Type II Diabetes, Glucose “Non-Sense,” and Islet Desensitization
Authors: Robertson R Paul
Published: September 2013

A universal finding in hyperglycemic patients with type II (non-insulin-dependent) diabetes mellitus is that all share a common defect in glucose recognition resulting in abnormal insulin secretion by pancreatic islet β-cells. This defect is 1) specific for glucose signals rather than global, 2) related to chronic hyperglycemia, and 3) partially reversible after brief treatment with insulin to induce normoglycemia and through use of other pharmacological agents without normalizing glucose levels. My perspective is that an essential component of this defect is secondary and may represent a state of homologous desensitization of the β-cell secretory apparatus to glucose. Elucidation of the biochemical mechanism(s) of defective recognition of glucose signals by β-cells— or glucose “non-sense”—in these patients will provide key insights into the pathogenesis of type II diabetes mellitus.
Evaluation and Clinical Applications of Measurement of Urinary Growth Hormone in Diabetic Subjects
Authors: Suzuki Kazuo , Miyata Hajime , Suzuki Takashi , Kajinuma Hiroshi
Published: September 2013

Quantities of growth hormone (GH) excreted into the urine over 24 h were measured by the highly sensitive sandwich enzyme immunoassay in 63 non-insulin-dependent diabetes mellitus (NIDDM) subjects, 6 insulin-dependent diabetes mellitus (IDDM) subjects, and 17 age-matched nondiabetic control subjects. GH-provocative tests with intravenous infusion of arginine revealed that urinary GH levels are closely correlated with the integrated concentrations of serum GH (r = .931, n = 14, P < .001). Furthermore, 24-h urinary GH in control and diabetic subjects was inversely related to body mass index (r = .359, n = 80, P < .001). The mean 24-h urinary GH in NIDDM subjects was 11.1 ± 1.9 ng/g creatinine (Cr), which was not significantly different from that in nondiabetic control subjects (9.2 ± 2.7 ng/g Cr). By contrast, the individual values for IDDM subjects varied widely, and their mean values (42.5 ± 20.8 ng/g Cr) were much greater than those in the control and NIDDM subjects (P < .01). The degree of glycemic control does not seem to affect 24-h urinary GH in NIDDM. The mean 24-h urinary GH in 7 subjects with proliferative diabetic retinopathy was comparable to that in subjects without retinopathy or with background retinopathy. Thus, the measurement of 24-h urinary GH appears to provide reliable assessments of endogenous GH secretion under physiological conditions and will be a useful tool for obtaining further insight into the role of GH in diabetes.
Association of IDDM and Attenuated Response of 2′,5′-Oligoadenylate Synthetase to Yellow Fever Vaccine
Authors: Bonnevie-Nielsen V , Larsen M L , Frifelt J J , Michelsen B , Lernmark Å
Published: September 2013

Basal and yellow fever vaccination-induced 2′,5′-oligoadenylate synthetase (2′,5′A) activity was determined in blood mononuclear cells (peripheral blood lymphocytes [PBLs]) from insulin-dependent diabetes mellitus (IDDM) and matched control subjects. The live attenuated yellow fever vaccine represented a primary stimulus in all subjects. First, basal 2′,5′A activity increased severalfold in response to yellow fever vaccination. In IDDM subjects, this increase was significantly lower (P = .025). Second, the 2′,5′A activity increased proportionately to the higher basal 2′,5′A activity in IDDM subjects. In control subjects, the increase in 2′,5′A activity was not dependent on the basal activity. There was no relationship between basal or stimulated 2′,5′A activity and age, sex, duration of IDDM, age at onset of IDDM, metabolic control, or HLA-DQ β-chain gene polymorphism. There is a direct relationship between 2′,5′A activity and latent viral infections associated with the presence of double-stranded RNA and with cellular interferons (IFNs) formed in response to viral infections. The higher basal 2′,5′A activity (P = .05) in relation to the stimulated activity may therefore signify a latent infection or the presence of double-stranded RNA in PBLs of IDDM subjects. In Vitro stimulation of PBLs showed increased IFN sensitivity in IDDM subjects. Analysis of 2′,5′A activity is proposed to be a sensitive measure of the activation of the IFN system and the level of latent infectivity.
Allotransplantation of Culture-Isolated Neonatal Rat Islet Tissue: Absence of MHC Class II Positive Antigen-Presenting Cells in Nonimmunogenic Islets
Authors: Hegre Orion D , Ketchum Robert J , Popiela Heinz , Eide Cindy R , Meloche R Mark , Serie Janet R , Moore Wayne V
Published: September 2013

When highly purified neonatal rat islet tissue, derived after 10 days in vitro, was allografted, it was found to be nonimmunogenic or weakly immunogenic. In contrast, nonislet pancreatic components, derived from the same culture system, transplanted with highly purified islet tissue resulted in rejection in 88% of cases. Extension of the culture period did not result in reduced immunogenicity of the nonislet material. Immunostaining of islet or nonislet tissue from the culture system failed to demonstrate major histocompatibility complex (MHC) class II positive cells in the islet tissue, whereas the presence of MHC class II staining cells in the nonislet components was clearly demonstrable. These results demonstrate that the islet tissue obtained by culture isolation isfree of cells capable of stimulating an allogeneic immune response and are consistent with the hypothesis that the absence of MHC class II positive antigen-presenting cells reduces the immunogenicity of the tissue and enhances the survival of allogeneic grafts.
Systematic Variation and Differences in Insulin-Autoantibody Measurements
Authors: Wilkin Terence J , Schoenfeld Steven L , Diaz Jose-Luis , Kruse Viggo , Bonifacio Ezio , Palmer Jerry P
Published: September 2013

Insulin autoantibodies (IAAs) are currently the subject of intensive investigation as potential markers for autoimmune insulitis. However, the results of different reports vary widely. In an attempt to elucidate the reasons for the discrepant reports and to initiate standardization procedures, the International Diabetes Workshop (IDW) undertook two studies in which 22 centers worldwidemeasured IAA in coded samples. The variance in binding signal from the 49 sera in study 1 was considerable, even when results were standardized, but was largely systematic and attributable to basic differences in assay type (liquid phase versus solid phase) and to differences in the ligand used (human vs. nonhuman insulin). In study 2, 5 sera were prepared and presented blindly to compare dilution curves, insulin-species specificity, interference from irrelevant serum proteins, precision, and dose-dependent displaceability. Many assays, both liquid and solid phase, were influenced by marked and unpredictable nonspecific binding, revealed by loss of parallelism between dilution curves in pooled normal serum and buffer, by variable binding signals with different normal sera, and by difficulty in distinguishing human insulin-specific from crossreactive IAA sera. It was concluded from the experience of both studies that variance could probably be reduced by using a standard curve with derived common units, a single species of ligand, and methodology to minimize the effect of nonspecific binding. Variation related to assay type was probably due to liquid-versus solid-phase systems being differentially more sensitive to certain aspects of antigen-antibody binding; this issue will be addressed in future serum exchanges and workshops.
Altered Acetylcholine and Norepinephrine Concentrations in Diabetic Rat Hearts: Role of Parasympathetic Nervous System in Diabetic Cardiomyopathy
Authors: Akiyama Naohiko , Okumura Kenji , Watanabe Yukio , Hashimoto Hidekazu , Ito Takayuki , Ogawa Kouichi , Satake Tatsuo
Published: September 2013

The concentrations of acetylcholine (ACh) as a parasympathetic marker and norepinephrine (NE) as a sympathetic marker were investigated in the hearts of rats 2, 4, and 8 wk after the inductionof diabetes by an injection of streptozocin (STZ; 65 mg/kg i.v.). ACh and NE were measured by high-performance liquid chromatography with electrochemical detection. Diabetic rats showed low body weight and heart weight at 2, 4, and 8 wk and higher heart-to-body weight ratio and bradycardiaat 8 wk, almost all of which were normalized after insulin treatment. Myocardial ACh and NE concentrations in the diabetic rats at 2 and 4 wk were not significantly different from those in age-matched control rats. However, ACh and NE concentrations in the diabetic rats at 8 wk significantly increased compared with the control rats. Diabetic rats at 8 wk also had increased myocardial choline concentration and choline acetyltransferase activity and decreased acetylcholinesterase activity. Insulin treatment normalized all of these changes in the diabetic rats. Thus, in STZ-induced diabetes (STZ-D), the concentrations of both cholinergic and noradrenergic neurotransmitters in the myocardium increased. The results of this study confirm a previously reported increase in sympathetic activity to the heart and also indicate that there is an increase in the synthesis and a decrease in the metabolism of ACh in STZ-D and that adequate insulin treatment normalizes these changes.
Autophosphorylation of Cultured Skin Fibroblast Insulin Receptors From Patients With Severe Insulin Resistance and Acanthosis Nigricans
Authors: Stuart Charles A , Pietrzyk Robert A , Peters Edward J , Smith Fannie E , Prince Melvin J
Published: September 2013

The severe insulin resistance with acanthosis nigricans seen in young women without insulin-receptor autoantibodies is characterized by hyperinsulinemia and decreased in vivo responsiveness to insulin. We evaluated the potential cellular defects in insulin-receptor binding and autophosphorylation in 12 subjects with this syndrome. When evaluated as a group, insulin binding to freshly isolated monocytes was 55% that of controls. Specific binding of insulin to skin fibroblasts in monolayer culture was 49% that of controls. Maximal insulin-stimulated receptor autophosphorylation was only 27% that of controls. Individual data demonstrated that the diminished autophosphorylation activity was out of proportion to the diminished fibroblast insulin binding in cell lines from most subjects and was <50% of the predicted activity in 6 of the 12 studied cell lines. These data are consistent with genetically determined defects leading to diminished numbers of cell surface insulin receptors with intact tyrosine kinase autophosphorylation in many of our cell lines. However, in at least half, there appeared to be an additional defect beyond insulin binding, resulting in a disproportionate decrease in insulin-sensitive phosphorylation of the insulin-receptor β-subunit.
Tolbutamide as Mimic of Glucose on β-Cell Electrical Activity: ATP-Sensitive K+ Channels as Common Pathway for Both Stimuli
Authors: Cook Daniel L , Ikeuchi Masatoshi
Published: September 2013

It is accepted for insulin-secreting cells in culture that the closure of ATP-sensitive K+ channels causes the glucose-dependent depolarization of pancreatic β-cells seen at subthreshold levels (<100 mg/dl) of glucose. The question remains for the more thoroughly studied β-cells in freshly dissected intact islets, however, whether closure of these channels is responsible for subthreshold glucose-dependent depolarization and suprathreshold glucose-dependent regulation of membrane electrical activity. To answer this, we took advantage of the ability of tolbutamide, an orally active antidiabetic agent, to specifically inhibit ATP-sensitive K+ channels in pancreatic β-cells to determine whether these channels are active at sub- and suprathreshold levels of glucose and whether channel closure by tolbutamide reproduces the electrophysiological effects of glucose stimulation. We recorded membrane electrical activity from freshly dissected adult mouse pancreatic islets exposed to various levels of glucose and tolbutamide. As previously found by others, tolbutamide depolarizes islet cells in the absence of glucose, but we have found that, although the depolarization can trigger Ca2+ action potentials (spikes), a glucose-dependent permissive factor may be required for the normal bursting pattern of spiking. More significantly, we found that, unlike other β-cell stimuli, tolbutamide specifically mimics the effects of glucose stimulation on the pattern of suprathreshold electrical activity. The effects were seen with levels of tolbutamide that correspond to those required to inhibit ATP-sensitive K+ channels. These data suggest that ATP-sensitive K+ channels are active at sub- and suprathreshold levels of glucose and may be the sole pathway by which either glucose or tolbutamide depolarizes β-cells and controls β-cell electrical activity.
Coordinate Decrease of Tissue Insulinlike Growth Factor I Posttranscriptional Alternative mRNA Transcripts in Diabetes Mellitus
Authors: Fagin James A , Roberts Charles T , LeRoith Derek , Brown Arleen T
Published: September 2013

In these studies, we examined the effect of excess levels of growth hormone (GH) on rat insulinlike growth factor I (IGF-I) gene expression in streptozocin-induced diabetes mellitus. A solution hybridization/RNase protection assay was used to simultaneously quantitate the relative tissue content of the variant IGF-I mRNA species arising from alternative splicing in the region encoding the COOH-terminal extension E-peptide (IGF-Ia and IGF-Ib). IGF-Ia and IGF-Ib mRNAs were markedly decreased in liver, kidney, and lung tissues of diabetic rats. Although GF stimulates IGF-I gene expression, chronic GH excess from implanted somatomammotropic tumors did not appropriately induce tissue IGF-I mRNA content in diabetic animals. Treatment of diabetic rats with insulin for 1 wk restored basal and GH-stimulated IGF-Ia and IGF-Ib mRNA content toward that present in tissues of nondiabetic rats. The ratio of IGF-Ia to IGF-Ib mRNA remained relatively constant for each tissue and was not affected by the diabetic state, chronic GH hyperstimulation, or insulin therapy, suggesting that posttranscriptional splicing is not a regulated event in these conditions. Thus, both circulating IGF-I levels and tissue IGF-I gene expression are profoundly decreased in this model of experimental diabetes. Diminished tissue availability of IGF-I from endocrine and/or paracrine sources may be responsible for the growth retardation seen in uncontrolled diabetes mellitus.
Functional and Morphological Changes in Mediobasal Hypothalamus of Streptozocin-induced Diabetic Rats: In Vitro Study of LHRH Release
Authors: Bestetti Gilberto E , Boujon Claude E , Reymond Marianne J , Rossi Giovanni L
Published: September 2013

To investigate the role of the mediobasal hypothalamus (MBH) in diabetic gonadal axis disorders, the MBHs of adult male streptozocin-induced diabetic (STZ-D) rats were examined after incubation in basal conditions or in K+-enriched medium and compared with those of controls. Diabetes lasted 1 mo. Both luteinizing-hormone-releasing hormone (LHRH) release and MBH morphology were studied. After incubation in basal conditions, the LHRH release was unchanged. By light microscopy, the dilated-axon cross sections were more numerous (P < .01) in the basal arcuate nucleus and in the median eminence. By electron microscopy, the ratio of exocytoses to neurosecretory granules observed in the median eminence axon cross sections was smaller (P < .05). The total LHRH immunoreactivity, the number of labeled axons, and the amount of positive material in the axons were reduced (P < .05). After incubation in K+-enriched medium, the LHRH release was markedly reduced (P < .01). The number and area of dilated-axon cross sections, possibly because of the relation between exocytosis and physiological dilation, were less augmented (P < .01). Whereas the number of exocytoses and the ratio of exocytoses to neurosecretory granules were not decreased, the total LHRH immunoreactivity and the number of labeled axons were reduced (P < .05). The releasable LHRH pool therefore seems to be exhausted in control MBH because of long-term stimulation and reduced in the MBH of STZ-D rats because of diabetes. In conclusion, STZ-D causes functional and anatomical MBH lesions that should be pathogenetically relevant for the disorders of the gonadal axis documented in this animal model.
Effects of Hyperglycemia on Function of Isolated Mouse Pancreatic Islets Transplanted Under Kidney Capsule
Authors: Korsgren Olle , Jansson Leif , Andersson Arne
Published: September 2013

The insulin release from isolated pancreatic islets grafted under the kidney capsule was examined by means of a modified kidney-perfusion technique. The grafts, consisting of 150 C57BL/6 or 250 C57BL/Ks mouse islets, were implanted syngeneically under the left kidney capsule of normoglycemic or alloxan-induced diabetic recipients 4 wk before the perfusion. In both mouse strains, islets grafted to normoglycemic animals showed an immediate distinct peak of insulin release when challenged with high glucose, whereas no response was observed from islets grafted to hyperglycemic mice. In a similar way in C57BL/KS mice, arginine stimulated insulin release from the islet grafts in normoglycemic but not in hyperglycemic recipients. Insulin treatment of the diabetic recipients, however, partially normalized the insulin response to glucose. Islet grafts were removed in toto and analyzed for contents of insulin, glucagon, somatostatin, and DNA or rates of glucose-stimulated (pro)insulin biosynthesis. In both mouse strains, islets implanted into hyperglycemic animals contained significantly less insulin, and their rates of (pro)insulin biosynthesis were markedly decreased. Insulin treatment only marginally affected these parameters. The glucagon content of the grafted islets was unaffected by the hyperglycemia in both strains of mice, whereas a significant decrease in the somatostatin content was observed in the C57BL/Ks mice. We concluded that grafted islets exposed to prolonged hyperglycemic stress become functionally impaired in mice of both strains. Our perfusion technique of islet-graft-bearing kidneys in combination with biochemical studies on the removed grafts provides a suitable model for studies of the effects of prolonged hyperglycemia on islet β-cell function
Epidemiology of IDDM in Black and White Children in Jefferson County, Alabama, 1979–1985
Authors: Wagenknecht Lynne E , Roseman Jeffrey M , Alexander W James
Published: September 2013

For the period of 1 January 1979 through 31 December 1985, an average annual incidence rate (IR) of 12.1/100,000 (95% confidence interval [10.4/100,000, 14.0/100,000]) of insulin-dependent diabetes mellitus (IDDM) was observed in Jefferson County, Alabama, among people <20 yr old. Hospital medical-record review was the primary source of case ascertainment. A large proportion of Black children in the county permitted race-specific analyses. The average annual IR among the Black children was less than half that observed in the White children (7.0/100,000 vs. 15.6/100,000, respectively). Nearly equal numbers of White boys and girls were diagnosed during this period; however, there were three times as many Black girls as Black boys diagnosed. Among the 134 Whites, age-specific annual IRs were highest in the 5- to 9- and 10- to 14-yr age groups. Little variation was observed in age-specific rates among the 41 Black subjects. A seasonal trend was evident in both races, with the fewest cases of IDDM diagnosed in the months of April through June (P < .001). No association between the incidence of diabetes and income level was found among White or Black children. Significant differences in the epidemiology of IDDM between White and Black children suggest an important avenue for studying the etiology of IDDM.