Angiotensin I converting enzyme gene polymorphism in non-insulin dependent diabetes mellitus

A total of 168 patients with non-insulin dependent diabetes (NIDDM) followed over 10 years were recruited in this study. The patients were divided into two groups: Group 1 patients had a stable renal function (N = 96) and Group 2 had a declining renal function (N = 72). Group 1 included those whose serum creatinine was normal five years ago but had increased to > or = 2 mg/dl or those who has reached end-stage renal failure (requiring dialysis) by the time of study. All patients were genotyped for the insertion/deletion (I/D) polymorphism of the ACE gene, the M235T polymorphism of the angiotensinogen (Atg) gene and the A1166C polymorphism of the angiotensin II type 1 receptor (AT1) gene. The genotype frequency distributions of M235T Atg and the A116C AT1 gene polymorphisms were not different between Group 1 versus Group 2. While the frequency of the ACE DD genotype in Group 1 (7.3%) was comparable to that of the general population, the DD frequency was significantly higher in Group 2 (26.4%) than in Group 1 (odds ratio, 4.56; 95% confidence interval, 1.80 approximately 11.56, P < 0.001). Among all 168 patients studied, the renal survival rate was significantly lower among DD than ID (P < 0.005) or II patients (P < 0.001). In patients with a declining renal function (Group 2), those with the DD genotype had a significantly shorter time interval from onset of diabetes to the initiation of dialysis (13.4 +/- 1.4 years) than those with ID (20.7 +/- 1.2 years, P < 0.01) or II genotypes (17.5 +/- 1.1 year, P < 0.01). Analysis of the clinical course of the three ACE genotypes revealed that the majority (95%) of patients with the DD genotype who had albuminuria progressed to end-stage renal disease within 10 years of diagnosis of diabetes. Our analysis also revealed that initiation and continuation of dialysis are associated with a progressive decrease in the frequency of the DD genotype. These results indicate that, in NIDDM, the ACE DD genotype has a high prognostic value for progressive deterioration of renal function. Moreover, the DD genotype appears to increase the mortality once dialysis is initiated.

Structural gene and complete amino acid sequence of Pseudomonas aeruginosa IFO 3455 elastase

The DNA encoding the elastase of Pseudomonas aeruginosa IFO 3455 was cloned, and its complete nucleotide sequence was determined. When the cloned gene was ligated to pUC18, the Escherichia coli expression vector, bacteria carrying the gene exhibited high levels of both elastase activity and elastase antigens. The amino acid sequence, deduced from the nucleotide sequence, revealed that the mature elastase consisted of 301 amino acids with a relative molecular mass of 32,926 daltons. The amino acid composition predicted from the DNA sequence was quite similar to the chemically determined composition of purified elastase reported previously. We also observed nucleotide sequence encoding a signal peptide and "pro" sequence consisting of 197 amino acids upstream from the mature elastase protein gene. The amino acid sequence analysis revealed that both the N-terminal sequence of the purified elastase and the N-terminal side sequences of the C-terminal tryptic peptide as well as the internal lysyl peptide fragment were completely identical to the deduced amino acid sequences. The pattern of identity of amino acid sequences was quite evident in the regions that include structurally and functionally important residues of Bacillus subtilis thermolysin.

Efficacy and safety profile of exenatide once weekly compared with insulin once daily in Japanese patients with type 2 diabetes treated with oral antidiabetes drug(s): results from a 26-week, randomized, open-label, parallel-group, multicenter, noninferiority study

BACKGROUND

Exenatide once weekly (QW) is an extended-release formulation of exenatide, a glucagon-like peptide-1 receptor agonist that reportedly improves glycemic control in patients with type 2 diabetes.

OBJECTIVE

The goal of this study was to test the hypothesis that exenatide QW is noninferior to insulin glargine, as measured by change in glycosylated hemoglobin (HbA(1c)) from baseline to end point (week 26 [primary end point]) in Japanese patients with type 2 diabetes who have inadequate glycemic control with oral antidiabetes drugs.

METHODS

In this open-label, parallel-group, multicenter, noninferiority registration study, patients were randomized (1:1) to add exenatide QW (2 mg) or once-daily insulin glargine (starting dose, 4 U) to their current oral antidiabetes drug treatment. The primary analysis was change in HbA(1c) from baseline to end point, evaluated by using a last-observation-carried-forward ANCOVA model, with a predefined noninferiority margin of 0.4%. Secondary analyses (a priori) included analysis of superiority for between-group comparisons of change in weight and the proportion of patients reaching HbA(1c) target levels of ≤7.0% or ≤6.5%.

RESULTS

The baseline characteristics of the exenatide QW (215 patients) and insulin glargine (212 patients) treatment groups were similar: mean (SD) age, 57 (10) years and 56 (11) years, respectively; 66.0% and 69.8% male; mean HbA(1c), 8.5% (0.82%) and 8.5% (0.79%); and mean weight, 69.9 (13.2) kg and 71.0 (13.9) kg. Exenatide QW was statistically noninferior to insulin glargine for the change in HbA(1c) from baseline to end point (least squares mean difference, -0.43% [95% CI, -0.59 to -0.26]; P < 0.001), with the 95% CI upper limit less than the predefined noninferiority margin (0.4%). A significantly greater proportion of patients receiving exenatide QW compared with insulin glargine achieved HbA(1c) target levels of ≤7.0% (89 of 211 [42.2%] vs 44 of 210 [21.0%]) or ≤6.5% (44 of 214 [20.6%] vs 9 of 212 [4.2%]) at end point (P < 0.001 for both). Patient weight was reduced with exenatide QW compared with insulin glargine at end point (least squares mean difference, -2.01 kg [95% CI, -2.46 to -1.56]; P < 0.001). Exenatide QW was well tolerated, with a lower risk of hypoglycemia compared with insulin glargine but a higher incidence of injection-site induration.

CONCLUSIONS

Exenatide QW was statistically noninferior to insulin glargine for the change in HbA(1c) from baseline to end point; these results suggest that exenatide QW may provide an effective alternative treatment for Japanese patients who require additional therapy to control their diabetes. ClinicalTrials.gov identifier: NCT00935532.

Role of glycemic control and blood pressure in the development and progression of nephropathy in elderly Japanese NIDDM patients

OBJECTIVE

To investigate the role of glycemic control and blood pressure in the development and progression of nephropathy and to suggest goals for glycemic control and blood pressure for the prevention of nephropathy in elderly Japanese NIDDM patients.

RESEARCH DESIGN AND METHODS

A total of 123 age- and diabetes duration-matched elderly Japanese NIDDM patients (aged 60-75 years; 74 normoalbuminuric and 49 microalbuminuric) were retrospectively studied for 6 years.

RESULTS

The group that developed microalbuminuria from normoalbuminuria (group NM: n = 24) showed a higher 6-year mean HbA1c than the group that remained normoalbuminuric (group NN: n = 50; 9.0 +/- 0.8 vs. 8.1 +/- 0.8%, P < 0.01) in spite of no significant difference in 6-year mean blood pressure (MBP). On the other hand, the group that progressed from microalbuminuria to overt proteinuria (group MP: n = 26) showed a higher 6-year MBP than the group that remained microalbuminuric (group MM: n = 23; 106 +/- 5 vs. 95 +/- 6 mmHg, P < 0.01) in spite of no significant difference in 6-year mean HbA1c. The cutoff level of HbA1c separating group NN from group NM was 8.5% (normal range < or = 6.5%), and that of MBP separating group MM from group MP was 100 mmHg.

CONCLUSIONS

Glycemic control is a more potent factor than blood pressure level on the development of microalbuminuria. However, as far as the progression of microalbuminuria to overt proteinuria is concerned, hypertension is the most crucial factor in elderly NIDDM patients. Suggested goals for glycemic control and blood pressure level for the prevention of nephropathy in elderly Japanese patients are an HbA1c of < or = 8.5% (equivalent to 7.8% in the current measurement of stable HbA1c; normal range < or = 5.8%) and an MBP of < or = 100 mmHg.

Diabetes associated with a novel 3264 mitochondrial tRNA(Leu)(UUR) mutation

OBJECTIVE

To present a novel mitochondrial DNA mutation in a diabetic family

RESEARCH DESIGN AND METHODS

The proband was a 64-year-old man. In the family, diabetes was maternally inherited. He had diabetes, cerebellar ataxia, cervical lipoma, hearing loss, olfactory dysfunction, ophthalmoplegia, and facial nerve bilateral palsy. On examination, early insulin secretion was blunted, and the M value on glucose clamp test was low. In muscle, ragged red fibers were not found. T-to-C mutation at position 3264 was detected in the proband (0.5% mutant DNAs in leukocyte and 30% in muscle), but was not detected in 201 normal individuals.

RESULTS

Heteroplasmy of mutation, maternal inheritance of diabetes, and symptoms related to mitochondrial dysfunction suggest the pathogenecity of this 3264 mutation. As for diabetes etiology, both impaired insulin secretion and decreased insulin sensitivity seem to be important. In phenotypic characteristics, the combination of cerebellar ataxia and lipoma is a symptom sometimes found in myoclonic epilepsy and ragged red fibers (MERRFs). Ophthamoplegia is a symptom of chronic progressive external ophthalmoplegia (CPEO). These suggest that our proband had phenotypic overlap with MERRF and CPEO. Conversely, facial nerve bilateral palsy is a rare finding. The pictures that focused on his cranial nerves were thus unique, suggesting the heterogeneity of mitochondrial DNA (mtDNA)-related diabetes.

CONCLUSIONS

A novel 3264 mitochondrial DNA mutation in diabetes gives new insight to the etiology of mitochondrial diabetes. Its pathogenecity supports the belief that the tRNA(Leu)(UUR) gene is an etiological hot spot of mitochondrial diseases.

Usefulness of revised fasting plasma glucose criterion and characteristics of the insulin response to an oral glucose load in newly diagnosed Japanese diabetic subjects

OBJECTIVE

To examine the usefulness of the revised criterion for fasting plasma glucose (FPG) in the diagnosis of diabetes recommended by the American Diabetic Association (ADA) (126 mg/dl, 7 mmol/l), and to characterize insulin response during the 75-g oral glucose tolerance test (OGTT) in newly diagnosed Japanese diabetic subjects.

RESEARCH DESIGN AND METHODS

A series of 2,121 Japanese subjects underwent a 75-g OGTT (0-3 h) and were divided into three groups (normal glucose tolerance [NGT], impaired glucose tolerance [IGT], and diabetes mellitus [DM] according to the current World Health Organization criteria. After the cutoff values of FPG that distinguish NGT and IGT from diabetes were analyzed, the usefulness of the ADA criterion for FPG was examined by comparing diagnostic parameters (sensitivity, specificity, and accuracy) with those for the cutoff value of 140 mg/dl. To assess insulin response, both the insulinogenic index (IsIx), a marker of early secretion, and the area under the insulin response curve (AUCins), a marker of total secretion, were compared between the DM, NGT, and IGT groups.

RESULTS

First, the FPG cutoff value distinguishing NGT from diabetes was 109 mg/dl. An FPG of 126 mg/dl showed a higher sensitivity (0.52 vs. 0.31), the same specificity (1.00), and a higher accuracy (0.82 vs. 0.74) than an FPG of 140 mg/dl, and it had a higher specificity (1.00 vs. 0.86) with a slightly lower accuracy (0.82 vs. 0.85) than an FPG of 109 mg/dl. Second, the FPG cutoff value differentiating IGT from diabetes was 113 mg/dl. An FPG of 126 mg/dl showed a higher sensitivity (0.52 vs. 0.31) and accuracy (0.80 vs. 0.74) and a similar specificity (0.97 vs. 1.00) compared with an FPG of 140 mg/dl, and it had a higher specificity (0.97 vs. 0.82) with the same accuracy (0.80) as an FPG of 113 mg/dl. Third, the DM group showed the lowest IsIx among the three groups at all FPG values. The AUCIns in the DM group increased along with FPG, reached the maximum level at an FPG of 110 mg/dl, and declined thereafter. AUCIns was higher in the DM group than in the NGT group at FPG values > or = 100 mg/dl.

CONCLUSIONS

The revised ADA criterion for FPG of 126 mg/dl may improve diagnostic sensitivity without loss of specificity in Japanese diabetic subjects when compared with an FPG criterion of 140 mg/dl. Although early insulin secretion was impaired, total insulin secretion did not seem to be reduced in newly diagnosed Japanese diabetic subjects.

T-cell insulitis found in anti-GAD65+ diabetes with residual beta-cell function. A case report

CASE HISTORY

We recently encountered a 65-year-old anti-GAD+ diabetic woman with residual beta-cell function who was proved to have T-cell insulitis. The proportion of CD4+ and CD8+ cells varied among individual islets, although CD4+ cells tended to be the predominant T-cell type in the islets examined. All of the islets examined still contained insulin, suggesting that beta-cell mass may have been preserved.

DISCUSSION

It is well known that lymphocytic infiltration of pancreatic islets, a condition referred to as "insulitis," is seen in acute-onset type 1 diabetes at autopsy and in biopsy specimens. However, there have been no proven cases of insulitis in type 1 diabetes with residual beta-cell function. We believe that this is the first type 1 diabetic patient with residual beta-cell function who was proven to have T-cell insulitis. This novel evidence will contribute to the proper classification and treatment of diabetes and to a better understanding of the pathophysiology of type 1 diabetes.

Well-differentiated adenocarcinoma arising from mature cystic teratoma of the mediastinum (teratoma with malignant transformation). Report of a surgical case

A surgical case of teratoma with malignant transformation (TMT) of the mediastinum in a 66-year-old man is reported. The unilocular, cystic, mediastinal mass, which had been seen in a chest radiograph 7 years earlier, was extirpated. The mass was histologically revealed to be a mature cystic teratoma containing skin and respiratory epithelial tissues, with some areas of well-differentiated adenocarcinoma. Surgical cases of TMT in the mediastinum, which have not received any preoperative chemotherapy or radiation therapy, are rare. By reviewing the previous literature on TMT in various organs, the authors distinguished two types of TMT, chemotherapy- or radiotherapy-induced TMT and naturally occurring TMT. The pathogenesis of these two types are discussed.

Complete nucleotide sequence of the structural gene for alkaline proteinase from Pseudomonas aeruginosa IFO 3455

The DNA-encoding alkaline proteinase (AP) of Pseudomonas aeruginosa IFO 3455 was cloned, and its complete nucleotide sequence was determined. When the cloned gene was ligated to pUC18, the Escherichia coli expression vector, the gene-incorporated bacteria expressed high levels of both AP activity and AP antigens. The amino acid sequence deduced from the nucleotide sequence revealed that the mature AP consists of 467 amino acids with a relative molecular weight of 49,507. The amino acid composition predicted from the DNA sequence was similar to the chemically determined composition of purified AP reported previously. The amino acid sequence analysis revealed that both the N-terminal side sequence of the purified AP and several internal lysyl peptide fragments were identical to the deduced amino acid sequences. The percent homology of amino acid sequences between AP and Serratia protease was about 55%. The zinc ligands and an active site of the AP were predicted by comparing the structure of the enzyme with of Serratia protease, thermolysin, Bacillus subtilis neutral protease, and Pseudomonas elastase.

Precise measurement of individual rapid eye movements in REM sleep of humans

An automated analyzer for individual eye movements (EMs) has been developed that enables precise analyses of their incidence. Three new parameters for each EM are obtained: EM magnitude, the angle and speed of eyeball rotation, and the energy of each EM. All rapid eye movement (REM) sleep EMs from 40 nights of polysomnography for 20 healthy young men were analyzed. The mean frequency of eye movement (EM frequency) was 15.9 per minute. Compared to conventionally analyzed rapid eye movement (REM) density, EM frequency was more sensitive to differences among sleep cycles, nights, and individuals. The mean EM rotation was 6.27 +/- 0.021 degrees, the mean speed of rotation was 58.73 +/- 0.18 degrees/second, and mean energy was 525.85 +/- 3.82 degrees2/second. The distribution of changes in these new parameters differed from conventional measures across REM episodes. The conventional measures, REM episode duration, and REM density increased progressively in successive REM episodes in an ascent-to-right pattern. However, the new parameters peaked in the second, followed by relatively low values, producing an inverted V pattern. This discrepancy could indicate physiological mechanisms of EM that are not revealed in conventional measures of REM sleep intensity.

A comparison of period amplitude analysis and FFT power spectral analysis of all-night human sleep EEG

Zero-cross and zero-derivative period amplitude analysis (PAA) data were compared with power spectral analysis (PSA) data obtained with the fast Fourier transform in all-night sleep EEG from 10 subjects. Although PAA zero-cross-integrated amplitude showed good agreement with PSA power in 0.3-2 Hz, zero-cross analysis appears relatively ineffective in measuring 2-4 Hz and above waves. However, PAA zero-derivative measures of peak-trough amplitude correlated well with PSA power in 2-4 Hz. Thus, while PAA appears able to measure the entire EEG spectrum, the analytic technique should be changed from zero cross to zero derivative at about 2 Hz in human sleep EEG. PAA and PSA both demonstrate robust and interrelated across-night oscillations in three frequency bands: delta (0.3-4 Hz); sigma (12-16 Hz); and fast beta (20-10 Hz). The frequencies between delta and sigma, and between sigma and fast beta, did not show clear across-night oscillations using either method, and the two methods showed lower epoch-to-epoch agreement in these intermediate bands. The causes of this reduced agreement are not immediately clear, nor is it obvious which method gives more valid results. We believe that the three strongly oscillating frequency bands represent fundamental properties of the human sleep EEG that provide important clues to underlying physiological mechanisms. These mechanisms are more likely to be understood if their dynamic properties are preserved and measured naturalistically rather than being forced into arbitrary sleep stages or procrustean models. Both PAA and PSA can be employed for such naturalistic studies. PSA has the advantages of applying the same analytic method across the EEG spectrum and rests on more fully developed theory. Combined zero-cross and zero-derivative PAA demonstrates EEG oscillations that closely parallel those observed with spectral power, and the PAA measures do not rely on assumptions about the spectral composition of the signal. In addition, both PAA techniques can measure the relative contributions of wave amplitude and incidence to total power: These waveform characteristics represent different biological processes and respond differentially to a wide range of experimental conditions.

Activation of the visual cortex imaged by 24-channel near-infrared spectroscopy

Near-infrared spectroscopy (NIRS) is a noninvasive technique for continuous monitoring of the amounts of total hemoglobin (total-Hb), oxygenated hemoglobin, (oxy-Hb) and deoxygenated hemoglobin (deoxy-Hb). The purpose of the present study was to demonstrate the utility of NIRS in functional imaging of the human visual cortex. A new NIRS imaging system enabled measurements from 24 scalp locations covering a 9 cm sq area. Topographic images were obtained from interpolations of the concentration changes between measurement points. Five healthy subjects between 25 and 49 years of age were investigated. After a resting baseline period of 50 s, the subjects were exposed to a visual stimulus for 20 s, followed by a 50 s resting period in a dimly lit, sound attenuating room. The visual stimulus was a circular, black and white, alternating checkerboard. In four of five subjects the visual cortex was the most activated area during visual stimulation. This is the first reported use of a NIRS-imaging system for assessing hemodynamic changes in the human visual cortex. The typical hemodynamic changes expected were observed; the total-Hb and oxy-Hb increased just after the start of stimulation and plateaued after 10 s of the stimulation period.

Dynamic relationships between sleep spindles and delta waves during a NREM period

All-night sleep EEGs from 7 normal young male adults were analyzed by a waveform recognition method using FFT-IFFT band pass filters. The total durations of sleep spindles and sleep delta waves in each 20-s epoch were measured and plotted on an X-Y graph with lines connecting the points in time sequence (dynamic two-component plot). The relationship between these two measures within a single NREM period showed three dynamic phases and one stationary period. In the first phase, spindles increased while delta remained at low level or increased slightly. In the second phase delta increased greatly while spindles decreased. In the third phase, delta decreased while spindles remained at a low level. There was a stationary period between the second and third phases, when delta maintained a higher level and spindles maintained a lower level. These dynamic descriptions reflect the underlying physiological mechanisms more directly than static sleep stages. They should also permit finer analyses of sleep in psychiatric and neurological disorders.

T-cell receptor alpha chain plays a critical role in antigen-specific suppressor cell function

Antigen-specific suppressor T-cell hybridomas release soluble suppressor factors (TsF) in the supernatant that modulate both in vivo delayed-type hypersensitivity and in vitro plaque-forming cell responses in an antigen-specific manner. To study the relationship between the T-cell receptor (TcR) and TsF, we developed a series of TcR alpha- or TcR beta- expression variants from suppressor T-cell hybridomas that expressed the CD3-TcR alpha/beta complex. We demonstrate that loss of TcR alpha but not TcR beta mRNA was accompanied by the concomitant loss of suppressor bioactivity. Homologous transfection of TcR alpha cDNA into a TcR alpha- beta+ clone reconstituted both CD3-TcR expression and suppressor function. Furthermore, suppressor activity from TcR beta- variants was specifically absorbed by antigen and anti-TcR alpha antibodies, but not by anti-CD3 or anti-TcR beta affinity columns. These data directly establish a role for the TcR alpha chain in suppressor T-cell function and suggest that the TcR alpha chain is part of the antigen-specific TsF molecule.

Stratified analyses for selecting appropriate target patients with diabetic peripheral neuropathy for long-term treatment with an aldose reductase inhibitor, epalrestat

AIMS

The long-term efficacy of epalrestat, an aldose reductase inhibitor, in improving subjective symptoms and nerve function was comprehensively assessed to identify patients with diabetic peripheral neuropathy who responded to epalrestat treatment.

METHODS

Stratified analyses were conducted on data from patients in the Aldose Reductase Inhibitor-Diabetes Complications Trial (ADCT). The ADCT included patients with diabetic peripheral neuropathy, median motor nerve conduction velocity > or = 40 m/s and with glycated haemoglobin (HbA(1c)) < or = 9.0%. Longitudinal data on HbA(1c) and subjective symptoms of the patients for 3 years were analysed (epalrestat n = 231, control subjects n = 273). Stratified analyses based on background variables (glycaemic control, grades of retinopathy or proteinuria) were performed to examine the relationship between subjective symptoms and nerve function. Multiple logistic regression analyses were conducted.

RESULTS

Stratified subgroup analyses revealed significantly better efficacy of epalrestat in patients with good glycaemic control and less severe diabetic complications. In the control group, no improvement in nerve function was seen regardless of whether symptomatic benefit was obtained. In the epalrestat group, nerve function deteriorated less or improved in patients whose symptoms improved. The odds ratio of the efficacy of epalrestat vs. control subjects was approximately 2 : 1 (4 : 1 in patients with HbA(1c) < or = 7.0%).

CONCLUSION

Our results suggest that epalrestat, an aldose reductase inhibitor, will provide a clinically significant means of preventing and treating diabetic neuropathy if used in appropriate patients.

Morphological and cytochemical characteristics of periodontal Ruffini ending under normal and regeneration processes

Current knowledge on the Ruffini endings, primary mechanoreceptors in the periodontal ligament is reviewed with special reference to their cytochemical features and regeneration process. Morphologically, they are characterized by extensive ramifications of expanded axonal terminals and an association with specialized Schwann cells, called lamellar or terminal Schwann cells, which are categorized, based on their histochemical properties, as non-myelin-forming Schwann cells. Following nerve injury, the periodontal Ruffini endings of the rat incisor ligament can regenerate more rapidly than Ruffini endings in other tissues. During regeneration, terminal Schwann cells associated with the periodontal Ruffini endings migrate into regions where they are never found under normal conditions. Also during regeneration, alterations in the expression level of various bioactive substances occur in both axonal and Schwann cell elements in the periodontal Ruffini endings. Neuropeptide Y, which is not detected in intact periodontal Ruffini endings, is transiently expressed in their regenerating axons. Growth-associated protein-43 (GAP-43) is expressed transiently in both axonal and Schwann cell elements during regeneration, while this protein is localized in the Schwann sheath of periodontal Ruffini endings under normal conditions. The expression of calbindin D28k and calretinin, both belonging to the buffering type of calcium-binding proteins, was delayed in periodontal Ruffini endings, compared to their morphological regeneration. As the importance of axon-Schwann cell interactions has been proposed, further investigations are needed to elucidate their molecular mechanism particularly the contribution of growth factors during the regeneration as well as development of the periodontal Ruffini endings.

Polymorphism of the solute carrier family 12 (sodium/chloride transporters) member 3, SLC12A3, gene at exon 23 (+78G/A: Arg913Gln) is associated with elevation of urinary albumin excretion in Japanese patients with type 2 diabetes: a 10-year longitudinal study

AIMS/HYPOTHESIS

We have shown previously that the SLC12A3 +78G/A polymorphism in exon 23 (Arg913Gln) was a new candidate for conferring susceptibility to diabetic nephropathy. The aim of this study was to confirm the effect of this polymorphism on the elevation of urinary albumin excretion in type 2 diabetic patients.

METHODS

We retrospectively studied 264 Japanese patients with type 2 diabetes over a ten-year period. The subjects were classified into two groups: (1) persistent normoalbuminuria or microalbuminuria, or improvement from microalbuminuria to normoalbuminuria (group N); and (2) progression from normoalbuminuria to microalbuminuria or overt proteinuria, or progression from microalbuminuria to overt proteinuria (group P). They were assessed for association with the +78G/A polymorphism.

RESULTS

The frequency of the +78A allele was significantly higher in group N than in group P (10% vs 1%, p=0.021). By logistic regression analysis and discriminant analysis, the substituted allele was shown to be an independent factor correlating negatively to the elevation of albumin excretion (p=0.043 and 0.022, respectively).

CONCLUSIONS/INTERPRETATION

The SLC12A3 +78A(+) genotype may have a protective effect against the development and/or progression of diabetic nephropathy in Japanese type 2 diabetic patients.

Chemotactic cytokine receptor 5 (CCR5) gene promoter polymorphism (59029A/G) is associated with diabetic nephropathy in Japanese patients with type 2 diabetes: a 10-year longitudinal study

We previously showed that polymorphisms of the promoter area of chemokine receptor 5 (CCR5) gene (59029G/A) and its agonist, regulated upon activation, normal T-cell expressed and secreted (RANTES) gene (-28C/G) were new candidates for susceptibility to diabetic nephropathy. The aim of this study was to confirm the effect of these polymorphisms on the development and progression of diabetic nephropathy. We performed a 10-year retrospective study of 191 Japanese type 2 diabetic patients with normoalbuminuria at baseline. The subjects were classified into two groups: (1) those with persistent normoalbuminuria (group N) and (2) those with progression from normoalbuminuria to microalbuminuria or overt proteinuria (group P). Then, their association with CCR5 59029G/A and RANTES -28C/G polymorphisms was assessed. The frequency of the RANTES -28G(+) genotype did nor differ between the two groups, but the CCR5 59029A(+) genotype had a significantly higher frequency in group P than in group N (83% versus 71%, p=0.04). By discriminant analysis, only the CCR5 59029A(+) genotype showed an independent positive correlation with the onset or progression of nephropathy (p=0.03, odds ratio=2.41, 95% CI=1.09-5.33). Therefore, the CCR5 59029A(+) genotype seems to be related the etiology of diabetic nephropathy in Japanese type 2 diabetics.

The current status of treatment-related severe hypoglycemia in Japanese patients with diabetes mellitus: A report from the committee on a survey of severe hypoglycemia in the Japan Diabetes Society

Despite great strides in pharmacotherapy for diabetes, there is increasing concern over the risk of hypoglycemia in patients with diabetes receiving pharmacotherapy as they become increasingly older. This has prompted the Japan Diabetes Society (JDS) to initiate a survey on the current status of severe hypoglycemia in clinical settings. In July 2015, following approval from the JDS Scientific Survey/Research Ethics Committee, the JDS extended an invitation to executive educators, who represented a total of 631 healthcare facilities accredited by the JDS for diabetes education, to participate in the proposed survey. Of these, those who expressed their willingness to participate in the survey were sent an application form required for obtaining ethical approval at these healthcare facilities and were then asked, following approval, to enter relevant clinical data on an unlinked, anonymous basis in a web-based registry. The current survey was fully funded by the JDS Scientific Survey/Research Committee. A case registry (clinical case database) was launched after facility-specific information (healthcare facility database) was collected from all participating facilities and after informed consent was obtained from all participating patients. With severe hypoglycemia defined as the "presence of hypoglycemic symptoms requiring assistance from another person to treat and preferably venous plasma glucose levels at onset/diagnosis of disease or at presentation clearly less than 60 mg/dL (capillary whole blood glucose, less than 50 mg/dL)", the current survey was conducted between April 1, 2014 and March 31, 2015, during which facility-specific information was collected from a total of 193 facilities with a total of 798 case reports collected from 113 facilities. Of the 193 respondent facilities, 149 reported having an emergency department as well, with the median number of patients who required emergency transportation services to reach these facilities totaling 4,962 annually, of which those with severe hypoglycemia accounted for 0.34% (17). The respondent facilities accommodated a total of 2,237 patients with severe hypoglycemia annually, with the number of patients thus accommodated being 6.5 patients per site. A total of 1,171 patients were admitted for severe hypoglycemia, with the number of patients thus admitted being 4.0 per site, who accounted for 52.3% of all patients visiting annually for severe hypoglycemia. A review of the 798 case reports collected during the survey revealed that 240, 480 and 78 patients had type 1 diabetes, type 2 diabetes, and other types of diabetes, respectively; those with type 2 diabetes were shown to be significantly older (median [interquartile range], 77.0 [68.0-83.0]) than those with type 1 diabetes (54.0 [41.0-67.0]) (P < 0.001); and the BMI was shown to be significantly higher for those with type 2 diabetes (22.0 [19.5-24.8] kg/m2 ) than for those with type 1 diabetes (21.3 [18.9-24.0] kg/m2 ) (P = 0.003). It was also found that the median estimated glomerular filtration rate (eGFR) was significantly lower among those with type 2 diabetes (50.6 mL [31.8-71.1]/min/1.73 m2 ) than among those with type 1 diabetes (73.3 [53.5-91.1] mL/min/1.73 m2 ) (P < 0.001). Again, the median HbA1c value at onset of severe hypoglycemia was shown to be 7.0 (6.3-8.1)% among all patients examined, 7.5 (6.9-8.6)% among those with type 1 diabetes, and 6.8 (6.1-7.6)% among those with type 2 diabetes, with the HbA1c value at onset of hypoglycemia being significantly lower among those with type 2 diabetes (P < 0.001). Antecedent symptoms of severe hypoglycemia were shown to be present, absent and unknown in 35.5, 35.6, and 28.9% of all patients, respectively, with the incidence of symptomatic hypoglycemia being significantly lower among those with type 1 diabetes (41.0%) than among those with type 2 diabetes (56.9%). The antidiabetic agents used in those with type 2 diabetes were insulin preparations (292 patients including 29 receiving concomitant sulfonylureas [SUs]) (60.8%), SUs (159 insulin-naïve patients) (33.1%), and no insulin preparations or SUs (29 patients) (6.0%). Of the 798 patients surveyed, 296 patients (37.2%) were shown to have required emergency transportation services for severe hypoglycemia before. Thus, the survey revealed, for the first time, the current status of treatment-related severe hypoglycemia in Japan and clearly highlights the acute need for implementing preventive measures against hypoglycemia not only through education on hypoglycemia but through optimization of antidiabetic therapy for those at high risk of severe hypoglycemia or those with a history of severe hypoglycemia.

Associations of insulin resistance and glycemic control with the risk of kidney stones

OBJECTIVE

The associations of insulin resistance and glycemic control with the risk of kidney stones were explored.

METHODS

Generally healthy Japanese (n=2,171) who visited Saiseikai Central Hospital (Tokyo, Japan) for a health check were included in a cross-sectional study. We calculated odds ratios (OR) of having kidney stones in terms of four measures: fasting serum insulin, homeostasis model assessment of insulin resistance (HOMA-IR), fasting plasma glucose (FPG) and glycosylated hemoglobin (HbA1c), adjusting for possible risk factors for kidney stones.

RESULTS

Fasting serum insulin and HOMA-IR were non-significantly associated with the risk of kidney stones, whereas FPG and HbA1c were significantly associated. Compared with those with an FPG of <100 mg/dL, the ORs in those with an FPG of 100 to <126 mg/dL and ≥126 mg/dL were 1.38 (95% confidence interval [CI] =0.95-2.00) and 1.83 (95% CI =1.09-3.06) (p for trend =0.016). In relation to those with an HbA1c of <5.5%, the ORs in those with an HbA1c of 5.5 to <6.0%, 6.0% to <6.5% and ≥6.5% were 1.16 (95% CI =0.76-1.79), 1.25 (95% CI =0.70-2.23) and 1.98 (95% CI =1.11-3.52), respectively (p for trend =0.027). The significant associations between glycemic control measures and the risk of kidney stones were preserved even after the adjustment for factors related to insulin resistance.

CONCLUSION

Glycemic control could be an independent risk factor for kidney stones.

Usefulness of stable HbA(1c) for supportive marker to diagnose diabetes mellitus in Japanese subjects

To evaluate the adequacy and usefulness of the stable glycated hemoglobin (HbA(1c)) value of 6.5% suggested by the Japan Diabetic Society in 1999 for supportive diagnostic marker of diabetes, we assessed the sensitivity and specificity of an HbA(1c) value of 6.5% in patients who were newly diagnosed by the 75 g oral glucose tolerance test (75g-OGTT). A total of 866 Japanese subjects underwent the 75g-OGTT and HbA(1c) measurement (normal range: 4.3-5.8%). They were divided into three groups [normal glucose tolerance (NGT), impaired glucose tolerance (IGT), and diabetes mellitus (DM)], using the WHO criteria, since no subject with impaired fasting glycemia (IFG) was observed. The cut-off value of HbA(1c) separating DM from NGT or DM from IGT on cumulative distribution curve analysis was 5.9% (sensitivity 0.76 and specificity 0.86) and 5.9% (sensitivity 0.76 and specificity 0.77), respectively. The sensitivity of an HbA(1c) of 6.5% for separation of DM from NGT or IGT by the same analysis was 0.49 and 0.49, respectively. Similarly, the specificity for separation of DM from NGT or IGT was 0.98 and 0.98, respectively. These results mean that 49% of diabetic subjects show an HbA(1c)> or =6.5%, and 51% have an HbA(1c) less than 6.5%, while only 2% of NGT and IGT subjects have an HbA(1c)> or =6.5%, and 98% have a value less than 6.5%. Therefore, the sensitivity of an HbA(1c) value of 6.5% in separating DM from NGT or IGT is low, and thus 6.5% is too high value to use when screening for diabetes. However, the specificity is very high, so an HbA(1c) of 6.5% is a useful supportive marker to diagnose diabetes.

Activation of visual cortex in REM sleep measured by 24-channel NIRS imaging

To visualize dreaming brain functions we studied hemodynamic changes in the visual cortex during the transition from non-rapid eye movement (NREM) to rapid eye movement (REM) sleep, using a 24-channel Near-Infrared Spectroscopy (NIRS) imaging method. Results were compared to the activation in visual cortex by visual stimulation during wakefulness. Subjects were four healthy males between 25 and 49 years of age. Five all-night polysomnographic and NIRS recordings were made. Increases in the oxygenated hemoglobin concentration in visual cortex were observed from nine of 14 REM periods. The activated areas were broader during REM sleep than during visual stimulation. These findings suggest that activation of visual cortex in REM sleep might represent dream-related brain activity.