334 research outputs found

    Selective cell response on natural polymer bio-interfaces textured by femtosecond laser

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    This study reports on the evaluation of laser processed natural polymer-chitosan, which is under consideration as a biointerface used for temporary applications as skin and cartilage substitutes. It is employed for tissue engineering purposes, since it possesses a significant degree of biocompatibility and biodegradability. Chitosan-based thin films were processed by femtosecond laser radiation to enhance the surface properties of the material. Various geometry patterns were produced on polymer surfaces and employed to examine cellular adhesion and orientation. The topography of the modified zones was observed using scanning electron microscopy and confocal microscopy. Test of the material cytotoxicity was performed by evaluating the life/dead cell correlation. The obtained results showed that texturing with femtosecond laser pulses is appropriate method to initiate a predefined cellular response. Formation of surface modifications in the form of foams with an expansion of the material was created under laser irradiation with a number of applied laser pulses from N = 1-5. It is shown that irradiation with N > 5 results in disturbance of microfoam. Material characterization reveals a decrease in water contact angle values after laser irradiation of chitosan films. Consequently, changes in surface roughness of chitosan thin-film surface result in its functionalization. Cultivation of MC3T3 and ATMSC cells show cell orientational migration concerning different surface patterning. The influence of various pulse durations (varying from tau = 30-500 fs) over biofilms surface was examined regarding the evolution of surface morphology. The goal of this study was to define the optimal laser conditions (laser energy, number of applied pulses, and pulse duration) to alter surface wettability properties and porosity to improve material performance. The acquired set of results indicate the way to tune the surface properties to optimize cell-interface interaction

    Hubungan Antara Perilaku Masyarakat dengan Kejadian Malaria di Wilayah Kerja Puskesmas Tombatu Kabupaten Minahasa Tenggara

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    Malaria masih menjadi salah satu penyebab masalah kesehatan terlebih lagi di negara-negara tropis dan sub tropis. Tujuan penelitian : mengenalisa hubungan perilaku masyarakat dengan kejadian malaria di wilayah kerja Puskesmas Tombatu Minahasa Tenggara. Penelitian ini menggunakan pendekatan crossectional yaitu mencari hubungan antara perilaku masyarakat dengan kejadian malaria di wilayah kerja Puskesmas Tombatu Minahasa Tenggara. Populasi penelitian adalah masyarakat di empat desa Tombatu yaitu, Desa Betelen, Tombatu, Tombatu 3 Selatan dan Tombatu 3 Timur,  yang dipilih 100 orang untuk menjadi responden. Hasil : penelitian menunjukan bahwa masyarakat yang memiliki pengetahuan baik sebanyak 54 orang (54%) sedangkan yang berpengetahuan buruk terdapat 46 orang (46%), masyarakat yang memiliki sikap yang positif atau baik terhadap malaria terdapat 92 orang (92%) dan yang masih bersikap negatif atau buruk terhadap malaria sebanyak 8 orang (8%) dan untuk masyarakat yang memiliki tindakan baik terdapat 75 orang (75%) dan yang buruk 25 orang (25%). Kesimpulan : terdapat hubungan perilaku masyarakat dengan kejadian malaria di wilayah kerja Puskesmas Tombatu Kabupaten Minahasa Tenggara. Saran: perlunya sosialisasi kepada masyarakat untuk meningktkan pengetahuan akan malaria.Kata Kunci : Perilaku masyarakat, Kejadian malaria, Puskesmas Tombatu

    Results and Lessons Learned on Robotic Assisted Kidney Transplantation

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    Introduction. Nowadays, minimally invasive surgery in kidney transplantation is a reality thanks to robotic assistance. In this paper, we describe our experience, how we developed the robotic assisted Kidney transplantation (RAKT) technique, and analyze our results. Material and Methods. This is a retrospective study of all RAKTs performed at our center between July 2015 and March 2020. We describe the donor selection, surgical technique, and analyze the surgical results and complications. A comparison between the first 20 cases and the following ones is performed. Results. During the aforementioned period, 82 living donor RAKTs were performed. The mean age was and 50 (61%) were male. Mean body mass index was and preemptive in 63.7% of cases. Right kidneys and multiple arteries were seen in 14.6% and 12.2%, respectively. Mean operative and rewarming time was and minutes, respectively. Five cases required conversion to open surgery because of abnormal kidney vascularization. Two patients required embolization for subcapsular and hypogastric artery bleeding without repercussion. Three kidneys were lost, two of them due to acute rejection and one because venous thrombosis. Late complications requiring surgery included one kidney artery stenosis, one ureteral stenosis, two lymphoceles, and three hernia repairs. We noticed a significant reduction in time between the first 20 cases and the following ones from to (). With a mean follow-up time of 1.8 years (SD 1.3), the mean creatinine was 1.52 (SD 0.7) and RAKT graft survival was 98%. Conclusions. The robotic approach is an attractive, minimally invasive method for kidney transplantation, yielding good results. Further studies are needed to consider it a standard approach

    Cell-Free DNA as a Prognostic Biomarker for Monitoring Muscle-Invasive Bladder Cancer

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    Cell-free DNA (cfDNA) has recently emerged as a real-time biomarker for diagnosis, monitoring and prediction of therapy response in tumoral disease. Here, we evaluated cfDNA as a prognostic biomarker for monitoring muscle-invasive bladder cancer (MIBC) patients at different follow-up time points. Blood samples from 37 MIBC patients who underwent radical cystectomy (RC) were collected at cystectomy and 1, 4, 12 and 24 months later. Plasma cfDNA amount and fragmentation patterns were determined. Four mutations were analyzed in cfDNA to detect circulating tumor DNA (ctDNA) during patient follow-up. During a median follow-up of 36 months, 46% of patients progressed; median time to progression was 10 months. cfDNA levels and ctDNA status four months after RC were identified as independent prognostic biomarkers of tumor progression (HR 5.290; p = 0.033) and cancer-specific survival (HR 4.199; p = 0.038), respectively. Furthermore, ctDNA clearance four months after RC was significantly associated with patients' clinical outcomes. In conclusion, cfDNA levels and ctDNA status four months after RC have prognostic implications in MIBC patients. In addition, cfDNA monitoring is useful to predict patient outcomes after RC. cfDNA analysis in the clinical setting could greatly improve MIBC patient management

    High Performance Multicell Series Inverter-Fed Induction Motor Drive

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    This document is the Accepted Manuscript version of the following article: M. Khodja, D. Rahiel, M. B. Benabdallah, H. Merabet Boulouiha, A. Allali, A. Chaker, and M. Denai, ‘High-performance multicell series inverter-fed induction motor drive’, Electrical Engineering, Vol. 99 (3): 1121-1137, September 2017. The final publication is available at Springer via DOI: https://doi.org/10.1007/s00202-016-0472-4.The multilevel voltage-source inverter (VSI) topology of the series multicell converter developed in recent years has led to improved converter performance in terms of power density and efficiency. This converter reduces the voltage constraints between all cells, which results in a lower transmission losses, high switching frequencies and the improvement of the output voltage waveforms. This paper proposes an improved topology of the series multicell inverter which minimizes harmonics, reduces torque ripples and losses in a variable-speed induction motor drive. The flying capacitor multilevel inverter topology based on the classical and modified phase shift pulse width modulation (PSPWM, MPSPWM) techniques are applied in this paper to minimize harmonic distortion at the inverter output. Simulation results are presented for a 2-kW induction motor drive and the results obtained demonstrate reduced harmonics, improved transient responses and reference tracking performance of the voltage in the induction motor and consequently reduced torque ripplesPeer reviewe

    HPV-negative Penile Intraepithelial Neoplasia (PeIN) With Basaloid Features.

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    Most human papillomavirus (HPV)-independent penile squamous cell carcinomas (PSCCs) originate from an intraepithelial precursor called differentiated penile intraepithelial neoplasia, characterized by atypia limited to the basal layer with marked superficial maturation. Previous studies in vulvar cancer, which has a similar dual etiopathogenesis, have shown that about one fifth of HPV-independent precursors are morphologically indistinguishable from high-grade squamous intraepithelial lesions (HSILs), the precursor of HPV-asssociated carcinomas. However, such lesions have not been described in PSCC. From 2000 to 2021, 55 surgical specimens of PSCC were identified. In all cases, thorough morphologic evaluation, HPV DNA detection, and p16, p53, and Ki-67 immunohistochemical (IHC) staining was performed. HPV-independent status was assigned based on both negative results for p16 IHC and HPV DNA. Thirty-six of the 55 PSCC (65%) were HPV-independent. An intraepithelial precursor was identified in 26/36 cases (72%). Five of them (19%) had basaloid features, morphologically indistinguishable from HPV-associated HSIL. The median age of the 5 patients was 74 years (range: 67 to 83 y). All 5 cases were p16 and DNA HPV-negative. Immunohistochemically, 3 cases showed an abnormal p53 pattern, and 2 showed wild-type p53 staining. The associated invasive carcinoma was basaloid in 4 cases and the usual (keratinizing) type in 1. In conclusion, a small proportion of HPV-independent PSCC may arise on adjacent intraepithelial lesions morphologically identical to HPV-associated HSIL. This unusual histologic pattern has not been previously characterized in detail in PSCC. p16 IHC is a valuable tool to identify these lesions and differentiate them from HPV-associated HSIL

    Pathogenesis of Penile Squamous Cell Carcinoma: Molecular Update and Systematic Review.

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    Penile squamous cell carcinoma (PSCC) is a rare but aggressive neoplasm with dual pathogenesis (human papillomavirus (HPV)-associated and HPV-independent). The development of targeted treatment is hindered by poor knowledge of the molecular landscape of PSCC. We performed a thorough review of genetic alterations of PSCC focused on somatic mutations and/or copy number alterations. A total of seven articles have been identified which, overall, include 268 PSCC. However, the series are heterogeneous regarding methodologies employed for DNA sequencing and HPV detection together with HPV prevalence, and include, in general, a limited number of cases, which results in markedly different findings. Reported top-ranked mutations involve TP53, CDKN2A, FAT1, NOTCH-1 and PIK3CA. Numerical alterations involve gains in MYC and EGFR, as well as amplifications in HPV integration loci. A few genes including TP53, CDKN2A, PIK3CA and CCND1 harbor both somatic mutations and copy number alterations. Notch, RTK-RAS and Hippo pathways are frequently deregulated. Nevertheless, the relevance of the identified alterations, their role in signaling pathways or their association with HPV status remain elusive. Combined targeting of different pathways might represent a valid therapeutic approach in PSCC. This work calls for large-scale sequencing studies with robust HPV testing to improve the genomic understanding of PSCC

    Applying multi-phase DES approach for modelling the patient journey through accident and emergency departments

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    Accident and Emergency departments (A&ED) are in charge of providing access to patients requiring urgent acute care. A&ED are difficult to model due to the presence of interactions, different pathways and the multiple outcomes that patients may undertake depending on their health status. In addition, public concern has focused on the presence of overcrowding, long waiting times, patient dissatisfaction and cost overruns associated with A&ED. There is then a need for tackling these problems through developing integrated and explicit models supporting healthcare planning. However, the studies directly concentrating on modelling the A&EDs are largely limited. Therefore, this paper presents the use of a multi-phase DES framework for modelling the A&ED and facilitating the assessment of potential improvement strategies. Initially, the main components, critical variables and different states of the A&ED are identified to correctly model the entire patient journey. In this step, it is also necessary to characterize the demand in order to categorize the patients into pipelines. After this, a discrete-event simulation (DES) model is developed. Then, validation is conducted through the 2-sample t test to demonstrate whether the model is statistically comparable with the real-world A&ED department. This is followed by the use of Markov phase-type models for calculating the total costs of the whole system. Finally, various scenarios are explored to assess their potential impact on multiple outcomes of interest. A case study of a mixed-patient environment in a private A&E department is provided to validate the effectiveness of the multi-phase DES approach

    Fluorescent Discrimination between Traces of Chemical Warfare Agents and Their Mimics

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    An array of fluorogenic probes is able to discriminate between nerve agents, sarin, soman, tabun, VX and their mimics, in water or organic solvent, by qualitative fluorescence patterns and quantitative multivariate analysis, thus making the system suitable for the inthe- field detection of traces of chemical warfare agents as well as to differentiate between the real nerve agents and other related compounds.Ministerio de Economía y Competitividad, Spain (Project CTQ2012- 31611), Junta de Castilla y León, Consejería de Educación y Cultura y Fondo Social Europeo (Project BU246A12-1), the European Commission, Seventh Framework Programme (Project SNIFFER FP7-SEC-2012-312411) and the Swedish Ministry of Defence (no. A403913
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