Single nucleotide polymorphisms in the proximal promoter region of the adiponectin (APM1) gene are associated with type 2 diabetes in Swedish caucasians

Adiponectin (APM1) is an adipocyte-derived peptide. The APM1 gene is located on chromosome 3q27 and linked to type 2 diabetes. In patients with type 2 diabetes, the adiponectin level in plasma is decreased in comparison to healthy subjects. To identify genetic defects of the APM1 gene that contribute to the development of type 2 diabetes, we genotyped 13 single nucleotide polymorphisms (SNPs) in 106 patients with type 2 diabetes, 325 patients with impaired glucose tolerance (IGT), and 497 nondiabetic control subjects in Swedish Caucasians by using dynamic allele-specific hybridization (DASH). We found that SNPs -11426(A/G) and -11377(G/C) in the proximal promoter region had significant differences of allele frequencies between type 2 diabetic patients and nondiabetic control subjects (P = 0.02 and P = 0.04, respectively). SNP-11426(A/G) was significantly associated with fasting plasma glucose in type 2 diabetic patients (P = 0.02) and in IGT subjects (P = 0.04), while the patients carrying CC and CG genotypes for SNP-11377(G/C) had a higher BMI than the patients with the GG genotype (P = 0.03). Haplotype analysis of 13 SNPs in the APM1 gene showed that estimates of haplotype frequencies in Swedish Caucasians are similar to those estimated in French Caucasians. However, no significant association of haplotypes with type 2 diabetes and IGT was detected in our study. The present study provides additional evidence that SNPs in the proximal promoter region of the APM1 gene contribute to the development of type 2 diabetes.     

Cigarette smoking and the risk of gestational and pregestational diabetes in two consecutive pregnancies

OBJECTIVE: Cigarette smoking during pregnancy may increase the risk of gestational diabetes mellitus (GDM) or pregestational diabetes mellitus (PDM). Smoking has been associated positively with hyperinsulinemia and insulin resistance in experimental studies, although the association with diabetes remains unclear. To further explore this issue, we examined the association with smoking in the largest prospective cohort study of GDM and PDM to date. RESEARCH DESIGN AND METHODS: The study population comprised 212190 women in the population-based Swedish Birth Registry who had their first and second deliveries between January 1987 and December 1995. Maternal characteristics were recorded in a standardized manner at the first prenatal visit, followed by a clinical examination and a standardized in-person interview to assess lifestyle habits. Women were categorized as nonsmokers, light smokers (one to nine cigarettes per day), or moderate-to-heavy smokers (at least 10 cigarettes per day). RESULTS: Women with GDM in their first pregnancy experienced an eight- to ninefold increased risk of GDM or PDM in their second pregnancy. Cigarette smoking was not associated with increased risk of these conditions. Neither women who smoked during their first and second pregnancies nor those who commenced smoking between pregnancies had a higher risk of GDM or PDM than nonsmokers. CONCLUSIONS: Our findings do not support an association between cigarette smoking and risk of GDM or PDM in young women of childbearing age.     

Effect of carbohydrate feeding on insulin action in skeletal muscle after surgical trauma in the rat

Metabolic stress after surgery is associated with peripheral insulin resistance. Recent studies have suggested that preoperative glucose can ameliorate postoperative decreases in insulin-stimulated glucose disposal. In the present experiments, we used a bowel-resection model of surgical trauma to test the hypothesis that elevations of serum insulin induced by preoperative oral glucose or ad libitum feeding affects postoperative insulin-stimulated glucose uptake in skeletal muscle. Insulin-stimulated glucose transport was measured in vitro in soleus muscles after surgical trauma in fasted rats given oral glucose or water before surgery. Insulin-stimulated glucose transport was also assessed in vitro in fasted or fed traumatized rats and non-traumatized control animals. In addition, stress hormones (glucagon, corticosterone, and adrenaline) were measured before and after surgical trauma in fasted rats and rats fed ad libitum. In vitro skeletal-muscle insulin sensitivity and responsiveness were reduced postoperatively in fasted animals that received oral glucose loads before bowel resections and in rats fed ad libitum or fasted before surgery versus non-traumatized rats (all P < 0.05). Stress-hormone concentrations after trauma did not differ between fed and fasted animals. In the current study, insulin sensitivity and responsiveness were reduced in isolated skeletal muscles after bowel resection, but neither preoperative glucose supplementation nor free intake of mixed nutrients ameliorated the development of postoperative insulin resistance.     

Molecular characterization of commercial porcine factor VIII concentrate

Commercial porcine factor VIII concentrate (Hyate:C) is effective in treatment of patients with hemophilia A who have circulating antibodies to factor VIII. The molecular forms of factor VIII in the concentrate were identified and evaluated in light of the known properties of porcine and human factor VIII. The factor VIII in the concentrate was isolated by tandem chromatography on gelatin-Sepharose and monoclonal anti-factor VIII-Sepharose. The factor VIII was 1% of the protein mass of the concentrate when calculated by either quantity of protein recovered or by radioimmunoassay. Both functional assay and Western blotting of the crude concentrate indicated that maximum coagulant function was achieved by proteolytic activation of procofactor forms of factor VIII. The factor VIII can be fractionated by cation-exchange high-performance liquid chromatography (HPLC) into two or three species of heterodimers depending on the lot. The specific activity of the purified porcine factor VIII was 550 U/mg using pooled porcine plasma at 1 U/mL as a standard. From this value, a factor VIII concentration in normal pig plasma of 2 micrograms/mL was calculated. This agreed well with a value of 3 micrograms/mL obtained by radioimmunoassay (RIA) of factor VIII in porcine plasma. In contrast, reported values for human factor VIII average 5800 U/mg, resulting in a calculated concentration in plasma of 0.2 microgram/mL. The finding that porcine plasma contains a significantly higher circulating mass of factor VIII than human plasma appears to explain previous difficulties in comparing porcine and human factor VIII in standard assays.     

The possible mechanisms by which phanoside stimulates insulin secretion from rat islets

We recently showed that phanoside, a gypenoside isolated from the plant Gynostemma pentaphyllum, stimulates insulin secretion from rat pancreatic islets. To study the mechanisms by which phanoside stimulates insulin secretion. Isolated pancreatic islets of normal Wistar (W) rats and spontaneously diabetic Goto-Kakizaki (GK) rats were batch incubated or perifused. At both 3 x 3 and 16 x 7 mM glucose, phanoside stimulated insulin secretion several fold in both W and diabetic GK rat islets. In perifusion of W islets, phanoside (75 and 150 microM) dose dependently increased insulin secretion that returned to basal levels when phanoside was omitted. When W rat islets were incubated at 3 x 3 mM glucose with 150 muM phanoside and 0 x 25 mM diazoxide to keep K-ATP channels open, insulin secretion was similar to that in islets incubated in 150 microM phanoside alone. At 16 x 7 mM glucose, phanoside-stimulated insulin secretion was reduced in the presence of 0 x 25 mM diazoxide (P<0 x 01). In W islets depolarized by 50 mM KCl and with diazoxide, phanoside stimulated insulin release twofold at 3 x 3 mM glucose but did not further increase the release at 16 x 7 mM glucose. When using nimodipine to block L-type Ca2+ channels in B-cells, phanoside-induced insulin secretion was unaffected at 3 x 3 mM glucose but decreased at 16 x 7 mM glucose (P<0 x 01). Pretreatment of islets with pertussis toxin to inhibit exocytotic Ge-protein did not affect insulin response to 150 microM phanoside. Phanoside stimulated insulin secretion from Wand GK rat islets. This effect seems to be exerted distal to K-ATP channels and L-type Ca2+ channels, which is on the exocytotic machinery of the B-cells.     

Performance of colposcopy in five sub-Saharan African countries

Objective  The performance of colposcopy provided in a screening study in five African countries was evaluated.
Design  Cross-sectional study.
Setting  Burkina Faso, Congo Brazzaville, Guinea Conakry, Mali and Niger.
Population  Women aged 25–59 years.
Methods  A total of 29 294 women participated in a cervical screening study in the five study sites, and newly trained local doctors performed colposcopy and directed biopsies as indicated. Using meta-analytical tools, four measures of colposcopy performance at different thresholds of colposcopic abnormalities were assessed. Sources of heterogeneity were also assessed.
Main outcome measures  Proportions of women receiving biopsies, adequate biopsies and women diagnosed with cervical intraepithelial neoplasia (CIN).
Results  Among 28 553 women with satisfactory colposcopy, 3101 had a colposcopic diagnosis of probable low-grade or worse lesions and 1128 probable high-grade or worse lesions. Overall, the measures that reached the set standards were proportion of biopsy taken at colposcopy threshold of probable high-grade or worse lesions (95%, 95% CI 90–100%) and proportion of adequate biopsy samples. The set standards were not met for the proportions of women diagnosed with CIN at different colposcopic abnormality thresholds. Detection of CIN2 or worse lesions increased with increasing colposcopic abnormality.
Conclusions  The performance of colposcopy in some of the African sites studied was comparable to that previously observed in other studies. With appropriate training, monitoring, continuing practice and quality assurance, adequate standards of colposcopy can be attained in sub-Saharan Africa.     

Isolation and characterization of a 60-residue intestinal peptide structurally related to the pancreatic secretory type of trypsin inhibitor: influence on insulin secretion.

We have isolated from pig intestine a 60-residue polypeptide initially identified by its inhibition of glucose-induced insulin secretion from perfused pancreas. The amino acid sequence of this porcine polypeptide was determined and found to be markedly similar to that of the pancreatic secretory trypsin inhibitor (41% residue identities). Furthermore, the disulfide arrangements of these two proteins appear identical, suggesting related overall conformations. However, the polypeptide, now named PEC-60 (peptide with N-terminal glutamic acid, C-terminal cysteine, and a total of 60 residues), was found not to inhibit trypsin. The amino acid sequence is also similar to that of a peptide recently isolated from rat bile/pancreatic juice which stimulates the release of cholecystokinin. The biological role of PEC-60 is not known, but the effect on insulin secretion and the homologies observed suggest important biological activities and interesting structural relationships.