Less invasive Achilles tendon reconstruction

<p>Abstract</p> <p>Background</p> <p>The optimal management of chronic ruptures of the Achilles tendon is surgical reconstruction. Reconstruction of the Achilles tendon using peroneus brevis has been widely reported. Classically, these procedures involve relatively long surgical wounds in a relatively hypovascular area which is susceptible to wound breakdown.</p> <p>Results</p> <p>We describe our current method of peroneus brevis reconstruction for the Achilles tendon using two para-midline incisions.</p> <p>Conclusion</p> <p>This technique allows reconstruction of the Achilles tendon using peroneus brevis preserving skin integrity over the site most prone to wound breakdown, and can be especially used to reconstruct the Achilles tendon in the presence of previous surgery.</p

A Complexed Sol-Gel (CSG) Approach to High Surface Area (HSA) Durable Ultra Active Platinum-Ruthenium Electro-Catalysts for Direct Methanol Fuel Cells

Direct Methanol Fuel Cell (DMFC) is a promising power source for continuous generation of energy without evolution of any toxic by-products and greenhouse gases. Pt-Ru has been the accepted gold standard anode electro-catalyst for DMFC, but significant advances are required to enhance its performance and stability. A complexed sol-gel (CSG) approach has been used to develop nanostructured powder materials. Herein we report a novel CSG process to synthesize nanoparticulate high specific surface area (HSA), completely unsupported Pt(Ru) based electro-catalyst exhibiting three fold higher electrochemically active surface area (ECSA) and ultra high electrochemical performance compared to commercially available Johnson Matthey Pt-Ru black catalyst, the currently accepted gold standard. Furthermore, in identical single full cell DMFC configuration tests for methanol oxidation, current and power densities ∼40% higher than that displayed by Johnson Matthey catalyst is achieved. Proton exchange membrane fuel cells (PEMFCs) are ubiquitously known for efficient continuous energy and power generation with reduced greenhouse emissions. Commercialization of low cost PEMFCs have however been thwarted by inferior catalyst activity and stability hence limited by loading constraints. • C), has been considered for applications that require faster start-up times, and frequent starts and stops such as automotive applications, material handling equipment, and auxiliary backup power systems. 1-5 On the other hand, methanol-powered direct methanol fuel cell (DMFC) are well suited for portable power applications in consumer electronic devices wherein the power requirements are low. 3-7 A significant fraction of the cost of DMFC and PEMFC arises from the use of precious metal catalysts hitherto platinum group-metal (PGM) catalysts currently used to accelerate electrochemical reactions at the electrodes. 3-8 For widespread commercialization of PEMFC and DMFCs, there is a critical need for continued advancements to minimize PGM loading or the development of equally performing non-PGM catalysts alternatives to reduce the cost. 3-10 The durability of catalysts is also a major issue under conditions of load-cycling in harsh corrosive environment. Mitigation of catalyst dissolution/degradation during operation of low and high-temperature fuel cells will certainly translate alone to higher performance leading to reduce costs. 3-11 Moreover, while addressing cost and durability, fuel cell performance and efficiency must also meet or exceed that of competing technologies (e.g. battery) to allow for market penetration and the benefits of this technology. In light of the current situation, it is of paramount importance to design and synthesize effective electro-catalysts with improved electrochemical activity, improved durability/stability, and significantly reduced precious metal loading to ultra-low levels exhibiting enhanced tolerance to air, fuel and system-derived impurities. To meet these tremendous constraints on performance and efficiency, durability and * Electrochemical Society Student Member. * * Electrochemical Society Active Member. z E-mail: [email protected] cost requirements of fuel cells, significant research has been conducted over the years focusing largely on identifying new materials, and developing novel design and fabrication methods for catalysts and supports. 3-13 Carbon monoxide generated during methanol oxidation reaction (MOR) as it is the surface bound intermediate at low temperatures during DMFC operation further inevitably leads to poisoning of the platinum catalyst surface which reduces the catalytic activity of platinum thus causing it to become inactive if used by itself. In this context, a novel complexed sol-gel process (CSG) has been developed by our group to synthesize unsupported nanocrystalline PtRu based binary, ternary and quaternary solid solutions having high ESCA with excellent electrochemical activity and durable microstructure for the methanol oxidation reaction

The Healing Process of Intracorporeally and In Situ Devitalized Distal Femur by Microwave in a Dog Model and Its Mechanical Properties In Vitro

Background: Limb-salvage surgery has been well recognized as a standard treatment and alternative to amputation for patients with malignant bone tumors. Various limb-sparing techniques have been developed including tumor prosthesis, allograft, autograft and graft-prosthesis composite. However, each of these methods has short- and long-term disadvantages such as nonunion, mechanical failures and poor limb function. The technique of intracorporeal devitalization of tumor-bearing bone segment in situ by microwave-induced hyperthermia after separating it from surrounding normal tissues with a safe margin is a promising limb-salvage method, which may avoid some shortcomings encountered by the above-mentioned conventional techniques. The purpose of this study is to assess the healing process and revitalization potential of the devitalized bone segment by this method in a dog model. In addition, the immediate effect of microwave on the biomechanical properties of bone tissue was also explored in an in vitro experiment. Methods: We applied the microwave-induced hyperthermia to devitalize the distal femurs of dogs in situ. Using a monopole microwave antenna, we could produce a necrotic bone of nearly 20 mm in length in distal femur. Radiography, bone scintigraphy, microangiography, histology and functional evaluation were performed at 2 weeks and 1, 2, 3, 6, 9 and 12 months postoperatively to assess the healing process. In a biomechanical study, two kinds of bone specimens, 3 and 6 cm in length, were used for compression and three-point bending test respectively immediately after extracorporeall

HIV and Other Sexually Transmitted Infections among Men Who Have Sex with Men Recruited by RDS in Buenos Aires, Argentina: High HIV and HPV Infection

The aim of this study was to estimate the prevalence of HIV and other STIs, among MSM from Buenos Aires (2007-2009).Responding Driven Sampling was used for recruitment of MSM. Participants completed a structured web-based survey and provided biological samples.A total of 496 MSM were studied for HIV, HBV, HCV, and T. pallidum infections. Chlamydia and HPV diagnoses were only performed in 98 and 109 participants, respectively. Prevalence of HIV was 17.3%, HBV 22.9%, HCV 7.5%, T. pallidum 20.5%, HPV 83.5%, and C. trachomatis 1.7%. In the year prior to the evaluation, 71% of the participants had had sex with men and/or trans and women (MMW) while 29% had not had sex with women (MM). Comparing MM to MMW, prevalence of HIV (30.7% vs. 11.9%, p<0.001), HBV (36.4% vs. 17.8%, p<0.001), T. pallidum (32.1% vs. 15.7%, p<0.001), and HPV (88.3% vs. 70.4%, p = 0.039) were significantly higher among MM, whereas no significant differences were found for HCV and C. trachomatis. The MM group had also significantly higher HIV incidence (5.60 vs. 4.28 per 100 persons-year, p = 0.032). HPV genotypes 16, 6, and 11 were the most frequently found; 40.7% of the MSM had more than one genotype and one high risk genotype was detected in 43.6% of participants.Both MM and MMW are at high risk of infection for HIV and other STIs. Rates of HIV, HBV, T. pallidum and HPV infections are higher in the MM group

Mechanical, pH and Thermal Stability of Mesoporous Hydroxyapatite

The stability of mesoporous hydroxyapatite (HAP) powder was studied following treatments of ultrasound, pH and heating. HAP was found to be mechanically stable up to (and including) 1 h continuous ultrasonic treatment in water. The HAP structure was also stable to pH, evidenced by practically identical XRD and FTIR spectra over the pH range 2–12. The surface area increased progressively with increasing acidity, reaching a maximum of 121.9 m 2 g −1 at pH 2, while alkaline conditions decreased the surface area to a minimum of 55.4 m 2 g −1 at pH 12. Heating in air had a significant influence on the structural and morphological properties of HAP, which underwent dehydroxylation to form oxyhydroxyapatite (OHAP) at temperatures ≥ 650 °C, and β-tricalcium phosphate (β-TCP) ≥750 °C. The surface area decreased at elevated temperatures due to agglomeration of HAP crystals by sintering, which was associated with an increased particle size

Efficacy of Endoscopic Submucosal Dissection for Superficial Gastric Neoplasia in a Large Cohort in North America

Background & Aims Endoscopic submucosal dissection (ESD) is a widely accepted treatment option for superficial gastric neoplasia in Asia, but there are few data on outcomes of gastric ESD from North America. We aimed to evaluate the safety and efficacy of gastric ESD in North America. Methods We analyzed data from 347 patients who underwent gastric ESD at 25 centers, from 2010 through 2019. We collected data on patient demographics, lesion characteristics, procedure details and related adverse events, treatment outcomes, local recurrence, and vital status at the last follow up. For the 277 patients with available follow-up data, the median interval between initial ESD and last clinical or endoscopic evaluation was 364 days. The primary endpoint was the rate of en bloc and R0 resection. Secondary outcomes included curative resection, rates of adverse events and recurrence, and gastric cancer-related death. Results Ninety patients (26%) had low-grade adenomas or dysplasia, 82 patients (24%) had high-grade dysplasia, 139 patients (40%) had early gastric cancer, and 36 patients (10%) had neuroendocrine tumors. Proportions of en bloc and R0 resection for all lesions were 92%/82%, for early gastric cancers were 94%/75%, for adenomas and low-grade dysplasia were 93%/ 92%, for high-grade dysplasia were 89%/ 87%, and for neuroendocrine tumors were 92%/75%. Intraprocedural perforation occurred in 6.6% of patients; 82% of these were treated successfully with endoscopic therapy. Delayed bleeding occurred in 2.6% of patients. No delayed perforation or procedure-related deaths were observed. There were local recurrences in 3.9% of cases; all occurred after non-curative ESD resection. Metachronous lesions were identified in 14 patients (6.9%). One of 277 patients with clinical follow up died of metachronous gastric cancer that occurred 2.5 years after the initial ESD. Conclusions ESD is a highly effective treatment for superficial gastric neoplasia and should be considered as a viable option for patients in North America. The risk of local recurrence is low and occurs exclusively after non-curative resection. Careful endoscopic surveillance is necessary to identify and treat metachronous lesions

Assessment of gestational age in newborn with birth-weight less than 2 kg

Neurological study of 190 newborns with birth-weight less than 2 Kg. was done. These babies were between 29 weeks to 40 weeks gestation of which 29 were babies of less than 33 weeks gestation and 161 were between 34 weeks to 40 weeks gestational age