Claudin-3 regulates bile canalicular paracellular barrier and cholesterol gallstone core formation in mice

Background & Aims

Most cholesterol gallstones have a core consisting of inorganic and/or organic calcium salts, although the mechanisms of core formation are poorly understood. We examined whether the paracellular permeability of ions at hepatic tight junctions is involved in the core formation of cholesterol gallstones, with particular interest in the role of phosphate ion, a common food additive and preservative.

Metabolic syndrome in Japanese patients with obstructive sleep apnea syndrome.

We investigated the prevalence of metabolic syndrome in patients with obstructive sleep apnea syndrome (OSAS) referred to a tertiary university-based medical center. A cross-sectional study of patients with a definite diagnosis of OSAS was performed using new diagnostic criteria for metabolic syndrome that were designed for the Japanese population. Clinical features and comorbidities related to metabolic syndrome were compared between 819 patients with OSAS (719 men and 100 women) and 89 control subjects without OSAS. Metabolic syndrome was significantly more common in the patients with OSAS than in the controls (49.5% vs. 22.0% for men, p < 0.01; 32.0% vs. 6.7% for women, p < 0.01). Men with OSAS (apnea-hypopnea index [AHI] > or =5/h) had a higher risk of metabolic syndrome compared with controls (odds ratio [OR]: 3.47; 95% confidence interval [CI]: 1.84-6.53). There was a significantly increased risk of metabolic syndrome in men with moderate OSAS (AHI: 15-29.9/h) (OR: 2.83; 95% CI: 1.42-5.66) and men with severe OSAS (AHI > or =30/h) (OR: 5.09; 95% CI: 2.67-9.71). Women with OSAS (AHI> or =5/h) also had an increased risk of metabolic syndrome (OR: 6.59; 95% CI: 1.47-29.38), and the risk was significantly higher in women with severe OSAS (AHI > or =30/h) (OR 14.00; 95% CI: 2.93-66.82). Risk factors for metabolic syndrome differed by gender: in men, age, body mass index (BMI), and OSAS (AHI > or =15/h) were significantly associated with metabolic syndrome, whereas, in women, BMI was the only risk factor for metabolic syndrome. The increase of metabolic syndrome in Japanese OSAS patients suggests that this patient population is burdened with multiple risk factors for cardiovascular disease.     

Association between insulin resistance and metabolic syndrome risk factors in Japanese

Aims/Introduction: It is important to identify individuals at risk of metabolic syndrome (MetS), namely those with insulin resistance. Therefore, the aim of the present study was to find anthropometric and metabolic parameters that can better predict insulin resistance. Subjects and Methods: We selected 3899 individuals (2058 men and 1841 women), excluding those with fasting plasma glucose (FPG) ≥126 mg/dL, on medication for hypertension, dyslipidemia or diabetes, and those with a history of advanced macrovascular disease. Using multivariate analyses, we selected components for obesity, lipids, and blood pressure based on the strength of their association with the homeostasis model assessment of insulin resistance (HOMA‐IR). Results: In multiple linear regression analysis, body mass index (BMI), waist circumference (WC), triglycerides (TG), high‐density lipoprotein–cholesterol (HDL‐C), and systolic blood pressure (SBP) were selected in men and women, and the effect of BMI on HOMA‐IR outweighed that of WC. In multiple logistic regression analysis, BMI, TG, and SBP were significantly associated with HOMA‐IR ≥2.5 in both genders, but WC and HDL‐C were only selected in men. Combinations of BMI, TG, SBP, and FPG showed higher HOMA‐IR values than those of the existing MetS components, considered useful for the identification of individual with higher insulin resistance. Conclusions: Body mass index, TG and SBP were selected as components significantly related to insulin resistance. The selected components were fundamentally adherent to the existing MetS criteria, the only difference being the measure of obesity, in which a stronger association with insulin resistance was observed for BMI than WC. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2011.00162.x, 2011)     

Asymmetry of the Leg Alignment Affects Trunk Bending in the Coronal Plane After Unilateral Total Knee Arthroplasty

Unilateral total knee arthroplasty (TKA) would produce asymmetric changes of lower extremity in patients with bilateral varus deformity. Our purpose was to investigate whether asymmetry of the leg alignment would affect trunk bending in the coronal plane after unilateral TKA. Twenty patients (mean 76 years old) with bilateral end-stage knee osteoarthritis (OA) participated. Spine images during relaxed standing were obtained on pre- and postoperative day 21. As a result, the shoulder tilted more to the TKA side and the pelvis inclined more to the contralateral OA side. These results suggested that the trunk would bend away from the contralateral OA side after unilateral TKA in patients with bilateral end-stage knee OA and varus deformity. Asymmetry of the leg alignment led to asymmetric trunk bending.     

Long-term observations of clinicopathological characteristics and outcome of Japanese patients with pauci-immune crescentic glomerulonephritis

Background

The clinicopathological characteristics and outcome with pauci-immune crescentic glomerulonephritis (CreGN) are presumed to vary over time. We examined the characteristics and outcome of Japanese patients with CreGN according to the treatment periods.

Patients and methods

From 1968 to 2011, we examined a total of 102 patients diagnosed with pauci-immune CreGN by renal biopsy. The patients were divided into three groups according to the treatment periods—Group I (1968–1988, n = 18), Group II (1989–2001, n = 37; when the nationwide survey of rapidly progressive glomerulonephritis [RPGN] was performed in Japan), and Group III (2002–2011, n = 47; after publication of the Japanese guideline for RPGN).

Results

There were no significant differences in blood pressure, renal function or anti-neutrophil cytoplasmic antibody titer between groups. On the other hand, the rate of crescent formation and degree of interstitial inflammatory cell infiltration were decreased in Group III. Serum creatinine (<3.0, 3.0–6.0, ≥6.0 mg/dL) and crescent formation (<30, 30–50, 50–80, ≥80 %) were significant renal prognostic factors in Group III [serum creatinine: hazard ratio (HR) 4.79, 95 % confidence interval (CI) 1.43–16.1, P = 0.011; crescent formation: HR 2.86, 95 % CI 1.06–7.73, P = 0.039]. Furthermore, renal survival rate of patients with crescent formation <50 % and patient survival rate of patients with serum creatinine <3 mg/dL were improved in Group III.

Conclusion

Patients with CreGN were diagnosed in the early phase of crescent formation and outcome has improved in recent years.     

Reduction of radiation exposure and image quality using dose reduction tool on computed tomography fluoroscopy

The purpose of our study was to measure the reduction rate of radiation dose and variability of image noise using the angular beam modulation (ABM) on computed tomography (CT) fluoroscopy. The Alderson-Rando phantom and the homemade phantom were used in our study. These phantoms were scanned at on-center and off-center positions at -12 cm along y-axis with and without ABM technique. Regarding the technique, the x-ray tube is turned off in a 100-degree angle sector at the center of 12 o'clock, 10 o'clock, and 2 o'clock positions during CT fluoroscopy. CT fluoroscopic images were obtained with tube voltages, 120 kV; tube current-time product per reconstructed image, 30 mAs; rotation time, 0.5 s/rot; slice thickness, 4.8 mm; and reconstruction kernel B30s in each scanning. After CT scanning, radiation exposure and image noise were measured and the image artifacts were evaluated with and without the technique. The reduction rate for radiation exposure was 75-80% with and without the technique at on-center position regardless of each angle position. In the case of the off-center position at -12 cm, the reduction rate was 50% with and without the technique. In contrast, image noise remained constant with and without the technique. Visual inspection for image artifacts almost have the same scores with and without the technique and no statistical significance was found in both techniques (p>0.05). ABM is an appropriate tool for reducing radiation exposure and maintaining image-noise and artifacts during CT fluoroscopy.     

Characterization of carotid atherosclerosis with black-blood carotid plaque imaging using variable flip-angle 3D turbo spin-echo: comparison with 2D turbo spin-echo sequences

Purpose

To compare the diagnostic performance of three-dimensional variable-flip-angle turbo spin-echo and two-dimensional turbo spin-echo sequences in carotid plaque imaging, with histological analysis as the standard of reference.

Materials and methods

Twenty-two patients scheduled for carotid endarterectomy underwent carotid plaque imaging including axial T1-weighted and T2-weighted two-dimensional turbo spin-echo, and coronal T1-weighted and T2-weighted three-dimensional variable-flip-angle turbo spin-echo sequences. The quality of images was visually graded using a three-point scale. The signal ratio of the arterial lumen to the plaque component, and that of the carotid plaque to the ipsilateral submandibular gland was calculated in each sequence. These ratios between two-dimensional and three-dimensional sequences were compared for each plaque component according to the histological category of the plaque.

Results

No significant difference was observed among the overall imaging quality scores of the two-dimensional and three-dimensional sequences, although three-dimensional sequences allowed visualization in arbitrary orientations, as well as depiction of small plaque components such as ulcerations and calcifications. The signal ratio of the plaque to the submandibular gland on T1-weighted three-dimensional sequence was significantly higher than that on two-dimensional sequence (p < 0.01), whereas no significant difference was found between two T2-weighted sequences.The signal ratios of the plaque to the submandibular gland of histology-defined soft plaque components were significantly higher on T1-weighted three-dimensional sequence than on two-dimensional sequence (p < 0.01), whereas no significant differences were observed between two T1-weighted sequences for hard components.

Conclusions

Three-dimensional variable-flip-angle turbo spin-echo is a promising tool for the diagnosis of carotid plaques.     

Cerebral dysfunction after coronary artery bypass surgery

Cerebral dysfunction after cardiac surgery remains a devastating complication and is growing in importance with our aging populations. Neurological complications following cardiac surgery can be classified broadly as stroke, encephalopathy (including delirium), or postoperative cognitive dysfunction (POCD). These etiologies are caused primary by cerebral emboli, hypoperfusion, or inflammation that has largely been attributed to the use of cardiopulmonary bypass. Preventative operative strategies, such as off-pump coronary artery bypass grafting (CABG), can potentially reduce the incidence of postoperative neurological complications by avoiding manipulation of the ascending aorta. Although off-pump CABG is associated with reduced risk of stroke, there are no convincing differences in POCD between off-pump and on-pump CABG. Recently, the focus of postoperative neurological research has shifted from managing cardiopulmonary bypass to patient-related factors. Identifying changes in brains of aged individuals undergoing cardiac surgery may improve strategies for preventing cerebral dysfunction. Advanced age is associated with more undiagnosed cerebrovascular disease and is a major risk factor for stroke and POCD following cardiac surgery. Preoperative cerebrovascular evaluation and adaptation of surgical strategies will provide preventative approaches for cerebral dysfunction after CABG. This review focuses on recent findings of the relationship between perioperative stress and underlying fragility of the brain in cardiac surgical patients.