The polymorphism linked to the human insulin gene: its lack of association with either IDDM or NIDDM in Japanese

Polymorphism of 5' portion of the human insulin gene was examined in 188 unrelated Japanese subjects (49 normal, 71 with IDDM, and 68 with NIDDM) using restriction endonuclease analysis. Restriction fragments were classified according to the insertion size: Class 1 (600 base pairs), Class 2 (1300 base pairs), and Class 3 (2000 base pairs). We found a very high frequency of Class 1 alleles (96.8%) and a low frequency of both Class 2 (0.8%) and Class 3 alleles (2.4%) and that approximately 94% of the genotypes were Class 1/Class 1 homozygote. In addition, there was no correlation of allelic or genotypic frequency with NIDDM or IDDM. We conclude that length polymorphism of the human insulin gene cannot be a useful marker for diabetes in Japanese.     

Liver Fibrosis is Associated with Ischemic Stroke Risk in Women but not Men: The REGARDS Study

BackgroundNonalcoholic fatty liver disease is inconsistently associated with ischemic stroke, with one study suggesting an association in women and not men. The relative importance of liver fibrosis, as opposed to fatty liver, for cardiovascular risk is increasingly appreciated. We hypothesized that advanced liver fibrosis is associated with incident ischemic stroke risk, and especially in women.MethodsWe performed a case-cohort study in the REasons for Geographic and Racial Differences in Stroke cohort. Black and white individuals aged 45 and older were recruited between 2003 and 2007 and followed for ischemic stroke. The Fibrosis-4 (FIB-4) score and Nonalcoholic Fatty Liver Disease Fibrosis Score (NFS) were calculated using baseline data for stroke cases and a cohort random sample; advanced liver fibrosis was classified using validated cutoffs. Cox proportional hazards models were used to estimate hazard ratios (HR) of stroke after adjusting for potential confounders. Sex differences were assessed.ResultsThere were 572 incident ischemic strokes (285 in women) over 5.4 (SD, 2.2) years. Advanced liver fibrosis was not significantly associated with ischemic stroke overall using the FIB-4 (HR 1.44; 95% CI 0.49–4.28) or NFS (HR 1.76; 95% CI 0.67–4.61). However, liver fibrosis was associated with stroke in women (HR 3.51; 95% CI 1.00–12.34) but not men (HR 0.70, 95% CI 0.16–3.16) (P = 0.098 for interaction) when using FIB-4. A similar but non-significant sex difference was seen for NFS.ConclusionAdvanced liver fibrosis may be associated with a higher risk of ischemic stroke in women but not men.     

A Case of Cerebellar Infarction Caused by Acute Subclavian Thrombus Following Minor Trauma

Subclavian steal syndrome caused by an acute thrombus is very rare. We present a case of cerebellar infarction with proximal subclavian artery thrombosis. A 56-year-old woman was admitted for sudden vertigo. One day prior to admission, she received a shoulder massage comprised of chiropractic manipulation. On examination, her left hand was pale and radial pulses were absent. Blood pressure was weak in the left arm. Downbeat nystagmus and a right falling tendency were observed. Brain MRI showed multiple acute infarctions in the left cerebellum. The findings of Doppler ultrasonography in the left vertebral artery were compatible with a partial subclavian artery steal phenomenon. Digital subtraction angiography demonstrated a large thrombus in the left subclavian artery. After heparin infusion, thrombus size markedly decreased. Cerebellar infarction caused by acute subclavian thrombosis following minor trauma is rare, but the thrombus can be successfully resolved with anticoagulation.     

Repeatability and reproducibility of apparent diffusion coefficient and fat fraction measurement of focal myeloma lesions on whole body magnetic resonance imaging

Objective:To assess intra- and inter-reader variability of apparent diffusion coefficient (ADC) and fat fraction (FF) measurement in focal myeloma bone lesions and the influence of lesion size.Methods:22 myeloma patients with focal active disease on whole body MRI were included. Two readers outlined a small (5–10 mm) and large lesion (>10 mm) in each subject on derived ADC and FF maps; one reader performed this twice. Intra- and inter-reader agreement for small and large lesion groups were calculated for derived statistics from each map using within-subject standard deviation, coefficient of variation, interclass correlation coefficient measures, and visualized with Bland–Altman plots.Results:For mean ADC, intra- and inter-reader repeatability demonstrated equivalently low coefficient of variation (3.0–3.6%) and excellent interclass correlation coefficient (0.975–0.982) for both small and large lesions. For mean FF, intra- and inter-reader repeatability was significantly poorer for small lesions compared to large lesions (intra-reader within-subject standard variation estimate is 2.7 times higher for small lesions than large lesions (p = 0.0071), and for inter-reader variations is 3.8 times higher (p = 0.0070)).Conclusion:There is excellent intra- and inter-reader agreement for mean ADC estimates, even for lesions as small as 5 mm. For FF measurements, there is a significant increase in coefficient of variation for smaller lesions, suggesting lesions >10 mm should be selected for lesion FF measurement.Advances in knowledge:ADC measurements of focal myeloma have excellent intra- and inter-reader agreement. FF measurements are more susceptible to lesion size as intra- and inter-reader agreement is significantly impaired in lesions less than 10 mm.     

Comparison of Complications between Endoscopic and Percutaneous Replacement of Percutaneous Endoscopic Gastrostomy Tubes

When replacing percutaneous endoscopic gastrostomy (PEG) tubes, an internal bolster may be retrieved either percutaneously or endoscopically. The aim of this study was to compare the complications of percutaneous and endoscopic method during PEG tube replacement. The medical records of 330 patients who received PEG tube replacement were retrospectively analyzed. According to the removal method of internal bolster, we categorized as endoscopic group and percutaneous group. Demographic data, procedure-related complications and risk factors were investigated. There were 176 cases (53.3%) in endoscopic group and 154 cases (46.7%) in percutaneous group. The overall immediate complication rate during PEG tube replacement was 4.8%. Bleeding from the stoma (1.3%) occurred in percutaneous group, whereas esophageal mucosal laceration (7.4%) and microperforation (0.6%) occurred in endoscopic group. The immediate complication rate was significantly lower in the percutaneous method (OR, 6.57; 95% CI, 1.47-29.38, P=0.014). In multivariate analysis, old age was a significant risk factor of esophageal laceration and microperforation during PEG tube replacement (OR, 3.83; 95% CI, 1.04-14.07, P=0.043). The percutaneous method may be more safe and feasible for replacing PEG tubes than the endoscopic method in old patients.     

The effect of surfactants on hydrate particle agglomeration in liquid hydrocarbon continuous systems: a molecular dynamics simulation study

Anti-agglomerants (AAs), both natural and commercial, are currently being considered for gas hydrate risk management of petroleum pipelines in offshore operations. However, the molecular mechanisms of the interaction between the AAs and gas hydrate surfaces and the prevention of hydrate agglomeration remain critical and complex questions that need to be addressed to advance this technology. Here, we use molecular dynamics (MD) simulations to investigate the effect of model surfactant molecules (polynuclear aromatic carboxylic acids) on the agglomeration behaviour of gas hydrate particles and disruption of the capillary liquid bridge between hydrate particles. The results show that the anti-agglomeration pathway can be divided into two processes: the spontaneous adsorption effect of surfactant molecules onto the hydrate surface and the weakening effect of the intensity of the liquid bridge between attracted hydrate particles. The MD simulation results also indicate that the anti-agglomeration effectiveness of surfactants is determined by the intrinsic nature of their molecular functional groups. Additionally, we find that surfactant molecules can affect hydrate growth, which decreases hydrate particle size and correspondingly lower the risk of hydrate agglomeration. This study provides molecular-level insights into the anti-agglomeration mechanism of surfactant molecules, which can aid in the ultimate application of natural or commercial AAs with optimal anti-agglomeration properties.

Schematic of anti-agglomeration effect of surfactants promoting gas hydrate particle dispersion.