Contributed Review: Review of thermal methods for space charge measurement

The space charge accumulation phenomenon has garnered great interest over the last two decades because of the increased use of direct current in high voltage electrical systems. In this context, a significant relevance has been achieved by the thermal methods, used for solid dielectrics. This paper presents a review of this non-destructive measurement system used for the measurement of space charge. The thermal pulse method, the thermal step method, and the laser intensity modulation method are described. For each configuration, the principle of operation, the thicknesses analyzed, and the spatial resolution are described, reporting also the main related application

Patch Testing in Non-Immediate Drug Eruptions

<p/> <p>The present review addresses the literature regarding the sensitivity and specificity of the various diagnostic methods for evaluating non-immediate (ie, occurring more than 1 hour after drug administration) hypersensitivity reactions associated with β-lactams and other antibiotics, anticonvulsants, heparins, iodinated contrast media, etc. Such reactions include several clinical entities, which range from mild reactions, such as maculopapular rash and delayed-appearing urticaria, to severe ones, such as acute generalized exanthematous pustulosis (AGEP), Stevens-Johnson syndrome, and toxic epidermal necrolysis (TEN). Clinical and laboratory studies indicate that a cell-mediated pathogenic mechanism is often involved in maculopapular rashes. However, this mechanism has also been demonstrated in other non-immediate reactions, such as urticarial and/or angioedematous manifestations, TEN, bullous exanthems, and AGEP. Patch tests, together with delayed-reading intradermal tests, lymphocyte transformation tests, and challenges, are useful tools for evaluating non-immediate drug eruptions. Patch tests can be performed with any form of commercial drugs and are safer than intradermal tests. However, patch tests are less sensitive than intradermal tests, and their sensitivity may vary, depending on the vehicle used.</p

Two-Dimensional Shear Wave Elastography Versus Transient Elastography: A Non-Invasive Comparison for the Assessment of Liver Fibrosis in Patients With Chronic Hepatitis C

In recent years, several non-invasive methods have been developed for staging liver fibrosis in patients with chronic hepatitis C. A 2D-Shear wave elastography (SWE) technique has been recently introduced on the EPIQ 7 US system (ElastQ), but its accuracy has not been validated in patients with chronic hepatitis C virus (HCV) infection. We enrolled 178 HCV patients to assess their liver fibrosis stage with ElastQ software using transient elastography as a reference standard. The best cut-off values to diagnose ≥ F2, ≥ F3, and F4 were 8.15, 10.31, and 12.65 KPa, respectively. Liver stiffness values had a positive correlation with transient elastography (r = 0.57; p &lt; 0.001). The area under the receiver operating characteristics (AUROC) was 0.899 for ≥ F2 (moderate fibrosis), 0.900 for ≥ F3 (severe fibrosis), and 0.899 for cirrhosis. 2D-SWE has excellent accuracy in assessing liver fibrosis in patients with chronic hepatitis C and an excellent correlation with transient elastograph

Prosthetic strap system for simplified ventral hernia repair. Its results in a porcine experimental model.

Abstract: Introduction Aiming to achieve a simplified ventral hernia repair, a proprietary shaped mesh was experimentally tested in the porcine model. The mesh is structured with a large central body and radiating straps. The friction of the straps passing through the tissues are hypothesized to be adequate to maintain the mesh in place during tissue ingrowth, avoiding classic point fixation while ensuring a wide coverage of the abdomen. Methods The mesh, having 6 radial straps, was placed using a sublay preperitoneal technique in 4 pigs. All straps were passed laterally through the abdominal wall and exteriorized from the skin. The straps were trimmed at the level of the skin, allowing the stumps to recoil into the subcutaneous space. The animal were euthanized at 1 and 4 months to determine the integration of the straps. Results Macroscopically all 24 straps were firmly incorporated within the abdominal wall. The tension free placement of the mesh by using the straps was effective. The friction of the straps passing through the tissues was adequate to keep the mesh well orientated. No dislocation of the implants was observed. The strap system also allowed a broader coverage of the abdominal wall, far beyond the wound opening. Conclusions The described arm system of the described implant seems to be effective in eliminating point fixation of the mesh. The fixation arms seemed to have ensured the mesh stayed orientated in all animals. A very wide lateral mesh placement was accomplished, assuring sufficient defect overlap when shrinkage occurs

Nerve degeneration in inguinal hernia specimens

BACKGROUND: The histological study of the herniated inguinal area is rare in the literature. This report is focused on the detection of structural changes of the nerves within tissues bordering the inguinal hernia of cadavers. Their physiopathological consequences are hypothesized. MATERIALS AND METHODS: Primary inguinal hernia was diagnosed in 30 fresh cadavers. Tissue specimens from the inguinal region close to and around the hernia opening were excised for histological examination. A control of the data was achieved through tissue samples excised from equivalent sites of the inguinal region in 15 cadavers without hernia. RESULTS: The detected nerves in the inguinal area demonstrated pathological changes such as fibrotic degeneration, atrophy, and fatty dystrophy of the axons. The thickening of the perineural sheath was constantly seen. These findings were consistently present, independent of the hernia type. CONCLUSIONS: The detected nerve alterations lead us to imagine a worsening, or even the cessation, of the nervous impulse to the muscles, leading to atrophy and weakening of the abdominal wall. This could represent one of the multifactorial causes of hernia genesis

Role and outcomes of laparoscopic cholecystectomy in the elderly.

Introduction: Laparoscopic cholecystectomy is the standard of treatment for gallstones disease and acute colecystitis. The prevalence of this disease increases with age and the population is aging in industrialized countries. So, in this study we report our experience in the treatment of gallstone disease in elderly patients, particularly analyzing the outcomes of laparoscopic approach. Methods: Between January 2010 and May 2014 we performed a total of 1227 cholecystectomies. In this retrospective study age group was the primary independent variable: 351 patients were 65-79 years of age and 65 were 80 years of age or older. Results: Only 65 patients (5.3%) of all population had primary open cholecystectomy, but the rate in young group was 3.7% respect the highest frequency (9.2%) in the elderly group. The conversion rate was higher (1.2%) in the older group but there was no significant difference with younger group. LC in emergency setting was performed in 10.3% of young patients and in 13.8% of elderly group. Conclusion: Laparoscopic cholecystectomy is a feasible and safe procedure in elderly patients and might be performed during the same hospitalization like definitive treatment of gallstone disease. The old age and subsequent comorbidity are the fundamental predictor of surgical outcomes. Elective treatment should be recommended when repeated gallstone symptoms have occurred in the elderly patient before the development of acute cholecystitis and related complications

Damage to the vascular structures in inguinal hernia specimens.

BACKGROUND: Few scientific reports to date describe the histological modification of structures outlining a hernia opening. This article is focused on the identification of the pathological changes in vascular structures in tissues excised from cadavers with inguinal hernia. A deeper comprehension of this topic could lead to essential improvements in the detection of hernia genesis. MATERIALS AND METHODS: Different kinds of hernia, including indirect, direct and mixed, were identified in 30 autopsied subjects. Tissue samples were resected for histological study from abdominal wall structures close to the hernia opening. Histological examination focused on the detection of structural changes in arteries and veins. The results were compared with tissue specimens excised from equivalent sites of the inguinal area in a control group of 15 fresh cadavers without hernia. RESULTS: Significant modification of vascular structures were identified in the tissue specimens examined. The veins demonstrated parietal fibrosis, perivascular edema and vascular dilation due to congestion and stasis. The arterial structures detected showed thickening of the media due to medial hyperplasia, ranging from luminal sub-occlusion to a manifest artery occlusion. These findings are present independent of hernia type in cadavers with inguinal hernia. These pathological changes were lacking in the control group of cadavers without hernia. CONCLUSIONS: The notable changes in vascular structures described in the report could be the result of a steady compressive effect exerted by the abdominal viscera in the inguinal area. These pathological changes could represent one of the factors involved in the weakening of the inguinal region leading to hernia protrusion