Blood pressure management and progression of chronic kidney disease in a canine remnant kidney model.

The canine remnant kidney model is fundamental to understanding the relationship between hypertension and chronic kidney disease (CKD). This study aimed to create a 1/16 remnant kidney model and to determine whether blood pressure (BP) control affects the progression of CKD. A group of dogs received BP treatment (group A) and another received BP treatment except for the first 2 weeks (group B). The remnant kidney model was induced using a two-step subtotal nephrectomy method; dogs received antihypertensive therapy. Systolic BP, blood urea nitrogen, serum creatinine, urinary protein, and creatinine levels were measured weekly. Kidney tissues were obtained at the conclusion of the study. Systolic BP was controlled to <160 mmHg in both groups for 18 weeks, except for the first 2 weeks in group B. Proteinuria was elevated after renal ligation in both groups, but gradually increased in group B and decreased in group A (p = 0.009). Blood urea nitrogen (p = 0.014) and creatinine (p = 0.020) levels were higher in group B than in group A. More histological damage was observed in group B than in group A. Induction of 1/16 nephrectomy successfully established CKD. Control of BP may be important to prevent or control the progression of CKD in dogs.

Open anatomical coracoclavicular ligament reconstruction using a tendon graft with an Endobutton loop.

We describe a technique of open anatomical coracoclavicular ligament reconstruction restoring both parts of the native ligament, aiming at achieving maximum stability of the acromioclavicular joint without disturbing the normal anatomy. Using the same anatomical principle of ligament reconstruction as in other joints, transosseous tunnels are created at the native footprints of the conoid and trapezoid ligaments. An autologous graft is fixed using an Endobutton continuous loop and a PEEK screw; adequate healing of the ligament is ensured with an appropriate working length. Although an open procedure, this technique offers several advantages. It can be easily reproduced using basic anatomical principles and simple cost-effective instrumentation. The implant does not have to be removed, important anatomical structures are respected, normal acromioclavicular joint kinematics are restored, the scar is cosmetically acceptable and post-operative morbidity is very low.

Noninvasive vascular occlusion with HIFU for venous insufficiency treatment: preclinical feasibility experience in rabbits.

Venous insufficiency is a common disease arising when veins of the lower limb become incompetent. A conventional surgical strategy consists in stripping the incompetent veins. However, this treatment option is invasive and carries complication risks. In the present study, we propose noninvasive high-intensity focused ultrasound (HIFU) to treat lower limbs venous insufficiency, in particular incompetent perforating veins (mean diameter between 2-6 mm). Sonication parameters were designed by numerical simulations using the k-Wave toolbox to ensure continuous coagulation of a vein with a diameter superior or equal to 2 mm. The selected ultrasound exposures were 4 s pulses in continuous wave mode. Two types of sonication were studied: (1) fixed pulses and (2) moving pulses at constant speed (0.75 mm s-1) across the vein. The potential of these exposures to thermally occlude veins were investigated in vivo on rabbit saphenous veins. The impact of vein compression during ultrasonic exposure was also investigated. Fifteen rabbits were used in these trials. A total of 27 saphenous veins (mean diameter 2.0 ± 0.6 mm) were sonicated with a transducer operated at 3 MHz. After a mean 15 d follow-up, rabbits were euthanized and venous samples were extracted and sent for histologic assessment. Only samples with the vein within the HIFU lesion were considered for analysis. Simulated thermal damage distribution demonstrated that fixed pulses and moving pulses respectively placed every 1.5 and 0.5 mm along the vein and delivered at an acoustic power of 85 W and for 4 s were able to induce continuous thermal damages along the vein segments. Experimentally, both treatment parameters (1) and (2) have proven effective to occlude veins with a success rate of 82%. Occlusion was always observed when compression was applied. Our results demonstrate that HIFU can durably and non-invasively occlude veins of diameters comparable to human veins.

Circulating TNF receptors predict cardiovascular disease in patients with chronic kidney disease.

Cardiovascular disease (CVD) is the main public health problem in patients with chronic kidney disease (CKD); however, there is no established biomarker for predicting CVD morbidity and mortality in CKD. The aim of this study was to evaluate the role of circulating tumor necrosis factor receptors (cTNFRs) in predicting CVD risk in CKD patients.We prospectively recruited 984 patients with CKD from 11 centers between 2006 and 2012. The levels of cTNFR1 and cTNFR2 were determined by performing an enzyme-linked immunosorbent assay. During the mean follow-up period of 4 years, 36 patients experienced a CVD event. The median serum concentrations of cTNFR1 and cTNFR2 were 2703.4 (225.6-13,057.7) and 5661.0 (634.9-30,599.6) pg/mL, respectively, and the cTNFR1 level was closely correlated with the cTNFR2 level (r = 0.86, P < .0001). The urinary protein-to-creatinine ratio (UPCR) and estimated glomerular filtration rate (eGFR) were significantly correlated with the cTNFR2 level (r = 0.21 for UPCR, r = -0.67 for eGFR; P < .001 for all). Similar correlations were observed for serum cTNFR1 (r = 0.21 for UPCR, r = -0.75 for eGFR; P < .001 for all). In the Cox proportional hazard analyses, cTNFR1 (hazard ratio [HR] 2.506, 95% confidence interval [CI] 1.186-5.295, P = .016) and cTNFR2 (HR 4.156, 95% CI 1.913-9.030, P < .001) predicted CVD risk even after adjustment for clinical covariates, such as UPCR, eGFR, and high-sensitivity C-reactive protein. cTNFR1 and 2 are associated with CVD and other risk factors in CKD, independently of eGFR and UPCR. Furthermore, cTNFRs could be relevant predictors of CVD in CKD patients.

Autoantibodies to islet amyloid polypeptide in diabetes.

Islet amyloid polypeptide (IAPP) is the constituent peptide of amyloid in pancreatic islets of Type 2 diabetic patients and in insulinomas. Amyloid formation in Type 2 diabetes is associated with islet cell destruction which may promote formation of autoantibodies to IAPP. An ELISA method has been developed to detect IAPP autoantibodies and used to assay serum from 80 non-diabetic subjects, 49 Type 1 and 228 Type 2 diabetic patients, and 10 patients with insulinomas. Microtitre plates coated with IAPP 1-37 were used to detect antibody binding followed by an alkaline phosphatase conjugated anti-human IgG. ELISA binding decreased with sample dilution and with pre-incubation of the samples with IAPP. The optical density of the substrate reaction was compared with results from a standard serum from a non-diabetic subject (OD ratio). Elevated OD ratios were detected in some subjects from each patient group but the Type 2 diabetic group had significantly higher titres than the non-diabetic subjects (p less than 0.001). The OD ratio was elevated (greater than mean + 2SD non-diabetic group) in 15% of Type 2 and 18% of Type 1 diabetic patients and in 20% with insulinomas. IAPP antibody levels did not correlate with age or gender of subjects, or duration of diabetes. IAPP autoantibodies could be an additional marker for B-cell damage in diabetes.