Place of plasma argon coagulation in the treatment of vascular abnormalities of the digestive tract in adults

The aim of our study is to evaluate the value of Argon Plasma Coagulation in the treatment of gastrointestinal vascular abnormalities. Patients and methods: This is a descriptive and analytical retrospective study, from January 2009 to September 2020. 198 patients who have benefited from treatment with Argon Plasma Coagulation for vascular anomalies of the digestive tract divided into 2 groups: -Group A: Patients with radial rectitis lesions (n = 107). -Group B: Patients with lesions of digestive angiodysplasia (n = 91). Results: The mean age of our patients was 64.95 ± 9.88 years [43 - 83] in group A, while in group B the mean age was 65.19 ± 14.29 years [40 - 91] with a clear male predominance in 72.5%. The majority of patients in group A were followed for prostate cancer in 33,8%, and 26.3% of patients in group B had chronic renal failure, followed by stomach cancer in 15.8%, and esophageal cancer in 10.5%. Clinical symptomatology was dominated by rectories in 40.2% in group A versus 46.8% in group B. Rectal involvement was dominated in group A in 98.1%, whereas in group B the lesions were mainly located in the stomach in 60.5%. The endoscopic evolution was favorable in all our patients with a clear improvement of rectal lesions and digestive angiodysplasia lesions. The total complication rate in our series was nil. Conclusion: Plasma Argon coagulation is a very effective method in the endoscopic treatment of digestive haemorrhages with good tolerability and a low complication rate. (AU)

Prospective Meta-analysis of Weight Loss Regained and Success Rate of Argon Plasma Coagulation to Suture and Surgery Procedures Post-bariatric Surgery: Status of the Art of Endoscopic Treatment.

BACKGROUND: This study performed a meta-analysis to compare the safety and efficacy of argon plasma coagulation (APC) concerning suture (SUT) and surgery (SUR). METHODS: The One-Way tests were applied, with p <0.05 significant. The value of R2 was analyzed (heterogeneity), and the risk of bias of articles was evaluated. RESULTS: A total of 34 studies were found, eight about APC, twenty about SUT, and six about SUR. For the percentage of Weight Loss Regained (%WLR), the means for APC, SUT, and SUR were 19.39 ± 10.94, 26.06 ± 16.71, and 17.05 ± 9.85, and for success rate (%SR), the means were 89.75 ± 16.75, 86.80 ± 11.44, and 76.00 ± 21.57, respectively with p >0.05, with R2 ≥ 50%. CONCLUSION: The APC proved to be efficient and safe like the other techniques.

Argon Beam Coagulation as an Adjuvant for Extended Curettage for Giant Cell Tumors of the Bone: A Study of 50 Cases / Coagulação por plasma de argônio como adjuvante à curetagem estendida em tumores de células gigantes do osso: Um estudo de 50 casos

Abstract Objective Extended curettage with adjuvants of giant cell tumors of bone is associated with a lower rate of recurrence of the tumor while preserving the adjacent joint. The present study was conducted to estimate the recurrence rate and functional outcome after using argon beam as an adjuvant for extended curettage. Methods We selected 50 patients with giant cell tumors, meeting all the inclusion criteria, who underwent extended curettage using high speed burr and argon beam photocoagulation between July 2016 to January 2019. On their follow-up visit, they were assessed for any complaints of pain and signs like tenderness, locally raised temperature, and decreased range of motion of the adjacent joint. Radiologically, the patients were assessed for any increased lucency around the cement mantle and uptake of the subarticular graft. Musculoskeletal Tumor Society Score (MSTS) was administered to the patients, and range of motion of the adjacent joint was compared with the contralateral joint. Results Recurrence was found in 4 patients, that is, an 8% recurrence rate. Twenty-six out of 28 patients with a tumor in the lower limb had a grade-5 weight bearing status 6 months from the surgery, and their range of motion was comparable to contralateral healthy joint with an average MSTS score of 27 (18-30). Conclusion Extended curettage of giant cell tumors using argon beam coagulation is associated with low recurrence rates of the tumor and is an effective modality in the treatment of these tumors besides having a functional outcome comparable to the healthy limb.

Resumo Objetivo A curetagem estendida com adjuvantes de tumores de células gigantes do osso está associada a uma menor taxa de recidiva da neoplasia e à preservação da articulação adjacente. Este estudo foi feito para estimar a taxa de recidiva e o resultado funcional após o uso de plasma de argônio como adjuvante à curetagem estendida. Métodos Cinquenta pacientes com tumores de células gigantes que atendiam a todos os critérios de inclusão foram selecionados para o estudo e submetidos à curetagem estendida com broca de alta velocidade e fotocoagulação com plasma de argônio entre julho de 2016 e janeiro de 2019. À consulta de acompanhamento, os pacientes foram avaliados quanto a quaisquer queixas de dor e sinais como sensibilidade, aumento local da temperatura e diminuição da amplitude de movimento da articulação adjacente. Radiologicamente, os pacientes foram avaliados quanto à presença de qualquer aumento de radiotransparência ao redor do manto de cimento e incorporação do enxerto subarticular. O questionário Musculoskeletal Tumor Society Score (MSTS) foi administrado aos pacientes e a amplitude de movimentação da articulação adjacente foi comparada à articulação contralateral. Resultados Quatro pacientes apresentaram recidiva, o que corresponde a uma taxa de 8%. Seis meses após a cirurgia, 26 de 28 pacientes com tumor no membro inferior tinham capacidade de sustentação de peso de grau 5 e amplitude de movimento comparável à articulação saudável contralateral, com pontuação MSTS média de 27 (intervalo de 18 a 30). Conclusão A curetagem estendida de tumores de células gigantes com coagulação por plasma de argônio está associada a baixas taxas de recidiva da neoplasia; é uma modalidade eficaz no tratamento desses tumores e o resultado funcional é comparável ao do membro saudável.

Effect of Plasma Argon Pretreatment on the Surface Properties of AZ31 Magnesium Alloy.

Climate change has evidenced the need to reduce carbon dioxide emissions into the atmosphere, and so for transport applications, lighter weight alloys have been studied, such as magnesium alloys. However, they are susceptible to corrosion; therefore, surface treatments have been extensively studied. In this work, the influence of argon plasma pretreatment on the surface properties of an AZ31 magnesium alloy focus on the enhancement of the reactivity of the surface, which was examined by surface analysis techniques, electrochemical techniques, and gravimetric measurements. The samples were polished and exposed to argon plasma for two minutes in order to activate the surface. Contact angle measurements revealed higher surface energy after applying the pretreatment, and atomic force microscopy showed a roughness increase, while X-Ray photoelectron spectroscopy showed a chemical change on the surface, where after pretreatment the oxygen species increased. Electrochemical measurements showed that surface pretreatment does not affect the corrosion mechanism of the alloy, while electrochemical impedance spectroscopy reveals an increase in the original thickness of the surface film. This increase is likely associated with the high reactivity that the plasma pretreatment confers to the surface of the AZ31 alloy, affecting the extent of oxide formation and, consequently, the increase in its protection capacity. The weight loss measurements support the effect of the plasma pretreatment on the oxide thickness since the corrosion rate of the pretreated AZ31 specimens was lower than that of those that did not receive the surface pretreatment.

Development of adenocarcinoma after radiofrequency ablation of barrett's esophagus associated to fundoplication and suppression-duodenal diversion procedure: a lesson to be learned / Adenocarcinoma em esôfago de barrett após ablação por radiofrequência associada a fundoplicatura e diversão duodenal

ABSTRACT Despite endoscopic eradication therapy being an effective and durable treatment for Barrett's esophagus-related neoplasia, even after achieving initial successful eradication, these patients remain at risk of recurrence and require ongoing routine examinations. Failure of radiofrequency ablation and argon plasma coagulation is reported in 10-20% of cases.

RESUMO Apesar de a terapia de erradicação endoscópica ser um tratamento eficaz e durável para a neoplasia relacionada ao esôfago de Barrett (BE), mesmo após a erradicação inicial bem-sucedida, esses pacientes permanecem em risco de recorrência e requerem exames de rotina contínuos. A falha na ablação por radiofrequência e na coagulação com plasma de argônio é relatada em 10-20% dos casos.

Endoscopic ablation combined with fundoplication plus acid suppression-duodenal diversion procedure for long segment barrett´s esophagus: early and long-term outcome / Ablação endoscópica combinada com fundoplicatura associada a diversão duodenal no esôfago de barrett longo: resultados precoce e de longo prazo

ABSTRACT BACKGROUND: The addition of endoscopic ablative therapy plus proton pump inhibitors or fundoplication is postulated for the treatment of patients with long-segment Barrett´s esophagus (LSBE); however, it does not avoid acid and bile reflux in these patients. Fundoplication with distal gastrectomy and Roux-en-Y gastrojejunostomy is proposed as an acid suppression-duodenal diversion procedure demonstrating excellent results at long-term follow-up. There are no reports on therapeutic strategy with this combination. AIMS: To determine the early and long-term results observed in LSBE patients with or without low-grade dysplasia who underwent the acid suppression-duodenal diversion procedure combined with endoscopic therapy. METHODS: Prospective study including patients with endoscopic LSBE using the Prague classification for circumferential and maximal lengths and confirmed by histological study. Patients were submitted to argon plasma coagulation (21) or radiofrequency ablation (31). After receiving treatment, they were monitored at early and late follow-up (5-12 years) with endoscopic and histologic evaluation. RESULTS: Few complications (ulcers or strictures) were observed after the procedure. Re-treatment was required in both groups of patients. The reduction in length of metaplastic epithelium was significantly better after radiofrequency ablation compared to argon plasma coagulation (10.95 vs 21.15 mms for circumferential length; and 30.96 vs 44.41 mms for maximal length). Intestinal metaplasia disappeared in a high percentage of patients, and histological long-term results were quite similar in both groups. CONCLUSIONS: Endoscopic procedures combined with fundoplication plus acid suppression with duodenal diversion technique to eliminate metaplastic epithelium of distal esophagus could be considered a good alternative option for LSBE treatment.

RESUMO RACIONAL: A adição de terapia ablativa endoscópica associado a inibidores da bomba de prótons ou fundoplicatura tem sido postulada para o tratamento de pacientes com esôfago de Barrett de segmento longo (EBSL), no entanto, essa conduta não evita o refluxo ácido/biliar nesses pacientes. A fundoplicatura com gastrectomia distal e gastrojejunostomia em Y de Roux (FGD-Y) foi proposta como procedimento de supressão de ácido, demonstrando excelentes resultados no seguimento a longo prazo. Não há relatos na literature com a combinação dessa estratégia terapêutica. OBJETIVOS: Determinar os resultados precoces e a longo prazo observados em pacientes com EBSL com ou sem dysplasia de baixo grau, submetidos a FGD-Y, combinado com terapia endoscópica. MÉTODOS: Estudo prospectivo incluindo pacientes com EBSL, empregando a classificação de Praga, sendo o comprimento circunferencial (C) e máximo (M) e confirmado por estudo histológico. Os pacientes foram submetidos à coagulação com plasma de argônio (CPA, 21 pacientes) ou ablação por radiofrequência (ARF, 31 pacientes). Após o tratamento, eles foram seguidos precoce e tardiamente (5-12 anos), mediante avaliação endoscópica e histológica. RESULTADOS: Foram observadas poucas complicações após o procedimento (úlcera ou estenose). Re-tratamento foi necessário em ambos os grupos de pacientes. A redução do comprimento do epitélio metaplásico foi significativamente melhor após ARF em comparação com CPA (10,95 versus 21,15 mm para C e 30,96 versus 44,41 mm para M). A metaplasia intestinal desapareceu em elevada porcentagem de pacientes, e os resultados histológicos a longo prazo foram bastante semelhantes em ambos os grupos. CONCLUSÕES: Procedimentos endoscópicos combinados com fundoplicatura e gastrectomia distal e gastrojejunostomia em Y de Roux, para eliminar o epitélio metaplásico do esôfago distal podem ser considerados uma boa opção alternativa para o tratamento da EBSL.

Argon plasma application on the surface of titanium implants: osseointegration study / Aplicação de plasma de argônio na superfície de implantes de titânio: estudo de osseointegração

Introduction: The development of new biomaterials with improved properties is a trend in regenerative medicine. The successful healing of implants is related to their osseointegration and the topographic geometry of their surface. Treatment with argon plasma acts on the surface of the implants, bringing several benefits to their osseointegration in the body. Material and Methods: Previously the in vivo study, the topography implants were observed by scanning electron microscopy (SEM). Following the implants were inserted in 14 male rats, and one perforation was made in the right and left tibias for implant placement without the surface treatment (control group), and with the argon plasma surface treatment (experimental group), respectively. The rats were euthanized at 4 weeks, a time in which tibia fragments were submitted for histological and histomorphometric examination, and torque removal test for comparison and analysis of osseointegration. Results: The SEM images showed the argon plasma surface treatment altered the topography. At the end of the study, both greater bone formation and better osseointegration were verified in the experimental group, and a statistically significant difference between the groups was observed. Conclusion: It was concluded that implants with this surface treatment can bring more practicality in the rehabilitation treatment, and more comfort in the patients' postoperative time (AU)

Introdução: O desenvolvimento de novos biomateriais com propriedades aprimoradas é uma tendência na medicina regenerativa. A cicatrização bem-sucedida dos implantes está relacionada à sua osseointegração e à geometria topográfica de sua superfície. O tratamento com plasma de argônio atua na superfície dos implantes, trazendo diversos benefícios para sua osseointegração no corpo. Materiais e Métodos: Antes do estudo in vivo, a topografia dos implantes foi observada por microscopia eletrônica de varredura (MEV). Em seguida, os implantes foram inseridos em 14 ratos machos, e uma perfuração foi feita nas tíbias direita e esquerda para a colocação do implante sem o tratamento de superfície (grupo controle) e com o tratamento de superfície de plasma de argônio (grupo experimental), respectivamente. Os ratos foram sacrificados após 4 semanas, momento em que fragmentos das tíbias foram submetidos a exame histológico e histomorfométrico, além do teste de remoção de torque para comparação e análise da osseointegração. Resultados: As imagens de MEV mostraram que o tratamento de superfície com plasma de argônio alterou a topografia. Ao final do estudo, foi verificada maior formação óssea e melhor osseointegração no grupo experimental, e foi observada diferença estatisticamente significativa entre os grupos. Conclusão: Concluiu-se que os implantes com esse tratamento de superfície podem trazer mais praticidade no tratamento de reabilitação e maior conforto no pós-operatório dos pacientes (AU)

Tratamiento endoscópico del esófago de Barrett con displasia de bajo y alto grado / Endoscopic treatment of Barrett's esophagus with low- and high-grade dysplasia

RESUMEN Introducción: El esófago de Barrett es una condición esofágica adquirida, que puede evolucionar a un adenocarcinoma. Con el paso de los años, la terapia endoscópica ha remplazado la cirugía en el tratamiento de esta afección. Objetivos: Mostrar los resultados de la aplicación de la técnica de resección endoscópica de la mucosa y la ablación con Hibrid-APC en pacientes portadores de esófago de Barrett con displasia de bajo o alto grado. Métodos: Se realizó un estudio descriptivo y retrospectivo en 29 pacientes entre los años 2014-2019, en el Servicio de endoscopias del Centro Nacional de Cirugía de Mínimo Acceso. Se estudiaron variables sociodemográficas, se estableció la clasificación endoscópica del esófago de Barrett, se describieron las características de la lesión, el diagnóstico histológico, la terapéutica endoscópica, la presencia de complicaciones, la resección incompleta y recidiva. Se aplicaron técnicas de estadística descriptiva y métodos no paramétricos. Resultados: Predominó el sexo masculino (58,62 %) y el grupo de 41-60 años (58,62 %). El segmento corto con lesiones planas y el largo con lesiones elevadas fueron más frecuentes (37,93 %). Se realizaron 15 resecciones y 14 ablaciones con Hibrid-APC; se observó una estenosis como complicación de la resección endoscópica de la mucosa y recidivas con ambas técnicas (5 pacientes, 17 %), tres relacionadas con la resección y dos con el Hibrid-APC. El Hibrid-APC alcanzó una efectividad terapéutica del 85,71 % y la resección del 80 %. Conclusiones: El tratamiento endoscópico con displasia de bajo y alto grado, mostró ser un procedimiento efectivo y seguro, con bajo porciento de complicaciones y recidivas.

ABSTRACT Introduction: Barrett's esophagus is an acquired esophageal condition that can evolve into an adenocarcinoma. Over the years, endoscopic therapy has replaced surgery in the treatment of this condition. Objectives: to show the results of the application of the endoscopic mucosal resection and Hybrid-APC ablation technique in patients with Barrett's esophagus with low-grade or high-grade dysplasia. Methods: a descriptive and retrospective study was carried out in 29 patients between 2014 and 2019, in the Endoscopy service of the National Center for Minimal Access Surgery. Social and demographic variables were studied; endoscopic classification of Barrett's esophagus was established, as well as the characteristics of the lesion, histological diagnosis, endoscopic therapy, the presence of complications, incomplete resection and recurrence were described. Descriptive statistics techniques and non-parametric methods were applied. Results: male gender (58.62%) and the group aged 41-60 years (58.62%) predominated. The short segment with flat lesions and the long segment with raised lesions were more frequent (37.93%). A number of 15 resections and 14 ablations were performed with Hybrid-APC; one stricture was observed as a complication of endoscopic mucosal resection and recurrences with both techniques (5 patients, 17%), three related to resection and two to Hybrid-APC. The Hybrid-APC achieved a therapeutic effectiveness of 85.71% and the resection one of 80%. Conclusions: endoscopic treatment with low- and high-grade dysplasia proved to be an effective and safe procedure, with a low percentage of complications and recurrences.

Argon plasma coagulation in radiation-induced proctitis

Abstract Background Argon plasma coagulation (APC) is a non-tactile ablative therapy that helps to stop rectal bleeding in patients who have developed actinic proctitis after exposure to radiotherapy. This approach seems to be more effective than medications or surgical procedures. Objective To review the literature to verify the effectiveness of APC in the treatment of patients with actinic proctitis induced by radiation therapies. Methods A systematic search was conducted on the following databases: MEDLINE/PubMed, LILACS, SCIELO, and the Cochrane Central Register of Controlled Trials. We identified 81 studies, and 5 of them fulfilled the inclusion criteria. Results In the articles included, a total of 236 patients were evaluated. Most of them were men (67.7%) with a mean age of 66.6 years. Prostate cancer was the main cause of actinic proctitis (67.3%), and control of the bleeding was achieved in 83.3% of the cases, after a mean of 1.67 session of APC. Moreover, 66 patients had complications with the treatment, and rectal pain was the most referred. Conclusions Argon plasma coagulation is a well-tolerated and effective treatment to control rectal bleeding in patients who underwent radiotherapy, and the number of sessions varies from 1 to 2, according to the case. (AU)

XPS Study in BiFeO3 Surface Modified by Argon Etching.

This paper reports an XPS surface study of pure phase BiFeO3 thin film produced and later etched by pure argon ions. Analysis of high-resolution spectra from Fe 2p, Bi 4f and 5d, O 1s, and the valence band, exhibited mainly Fe3+ and Bi3+ components, but also reveal Fe2+. High-energy argon etching induces the growth of Fe(0) and Bi(0) and an increment of Fe2+, as expected. The BiFeO3 semiconductor character is preserved despite the oxygen loss, an interesting aspect for the study of the photovoltaic effect through oxygen vacancies in some ceramic films. The metal-oxygen bonds in O 1s spectra are related only to one binding energy contrary to the split from bismuth and iron reported in other works. All these data evidence that the low-pressure argon atmosphere is proved to be efficient to produce pure phase BiFeO3, even after argon etching.

Argón plasma: respuesta terapéutica y calidad de vida en pacientes con proctitis actínica crónica hemorrágica / Impact of exclusive breastfeeding withdrawal on the health of babies

Introducción: La proctitis actínica crónica hemorrágica (PACH) se presenta secundaria a la radioterapia pélvica. La coagulación con argón plasma (APC) es una terapéutica eficaz, segura, de fácil uso y relativo bajo costo. Objetivo: Describir la respuesta terapéutica a corto y largo plazo del APC en pacientes con PACH, así como evaluar la calidad de vida antes y después de la intervención. Material y Métodos: Estudio observacional, prospectivo de serie de casos en 46 pacientes con PACH, atendidos en el Centro Nacional de Cirugía de Mínimo Acceso entre 2017 y 2020. Se emplearon medidas de resumen y comparación de medias (t de Student pareada) para la hemoglobina inicial y final, así como para los puntajes de calidad de vida aplicados antes y después de la intervención. Para determinar el tiempo libre de resangrado se utilizó l Método de Kaplan-Meier. Se estimó una significación menor a 0.05 para un intervalo de confianza de 95 por . Resultados: Se necesitó una media de 3,6 ± 2,394 sesiones de APC. La media de hemoglobina se incrementó 1,9 g/L. La respuesta terapéutica a corto plazo se observó en 100 por ciento de los pacientes y a largo plazo en 91,3 . La media de puntaje para la calidad de vida descendió en 12,065 puntos (p˂ 0,00), La percepción global percibida se incrementó en una media de 7.326 puntos (p˂ 0,00). Conclusiones: El APC tiene buena respuesta terapéutica a corto y largo plazo con pocas sesiones y bajo número de complicaciones, con mejoría de la calidad de vida de los pacientes(AU)

Introduction: Chronic hemorrhagic radiation proctitis (CHRP) appears secondary to pelvic radiotherapy. Argon plasma coagulation (APC) is an effective, safe, easy-to-use, and relatively inexpensive therapy. Objective: To describe the short- and long-term therapeutic response of APC in patients with CHRP, as well as to evaluate the quality of life before and after the intervention. Material and Methods: Observational, prospective case series study of 46 patients with CHRP, treated at the National Center for Minimally Access Surgery between 2017 and 2020. Summary measures and comparison of means (paired Student's t-test) were used for baseline and final hemoglobin, as well as for the quality of life scores applied before and after the intervention. The Kaplan-Meier method was used to determine the recurrence free time. A level of significance less than 0.05 was estimated for a 95 por ciento confidence interval. Results: A mean of 3,6 ± 2,394 APC sessions was required. The mean hemoglobin increased 1,9 g / L. Short-term therapeutic response was observed in 100 % of patients, and long-term in 91,3 por ciento. The mean score for quality of life decreased by 12,065 points (p˂ 0,00). The perceived global perception increased by a mean of 7,326 points (p˂ 0,00). Conclusions: APC has a good therapeutic response in the short and long term with few sessions and a low number of complications, with an improvement in the quality of life of the patients(AU)

Good Clinical Practices on Argon Plasma Coagulation Treatment for Weight Regain Associated with Dilated Gastrojejunostomy Following Roux-en-Y Gastric Bypass: a Brazilian-Modified Delphi Consensus.

INTRODUCTION: Argon plasma coagulation (APC) alone is effective and safe at treating weight regain following Roux-en-Y gastric bypass (RYGB). However, technical details of the treatment vary widely among studies. Therefore, we aimed to create good clinical practice guidelines through a modified Delphi consensus, including experts from the collaborative Bariatric Endoscopy Brazilian group. METHODS: Forty-one locally renowned experts were invited to the consensus by email. Experiences of > 150 APC-treated cases or authorship of relevant articles were the eligibility criteria. An initial questionnaire with short-answer questions was distributed to the experts. The organizing committee converted the responses into statements for an online 2-day voting webinar. Consensus was defined as more than 67% of positive answers. Three consecutive voting rounds were planned with discussion and statement refinements between rounds. RESULTS: Thirty-seven experts fulfilled eligibility criteria and attended the live webinar voting. The total number of patients treated by the panel was 12,349. By the third round, all 79 statements reached consensus. The recommendations include the definition of dilated gastrojejunal anastomosis as ≥ 15 mm, minimum regain of 20% of the lost weight to indicate the APC therapy, 6 to 8 weeks as the ideal interval between ablation sessions, and stopping treatment when the stoma reaches < 12 mm of breadth. CONCLUSIONS: This consensus provides several recommendations based on a highly experienced panel of endoscopists. Although it covers most aspects of the treatment, the level of evidence is low for the majority of the statements. Therefore, bariatric endoscopists should be constantly attentive to new evidence on APC treatment.

Synthesis of poly (N-vinyl pyrrolidone) (PVP) nanogels by gamma irradiation using different saturation atmospheres

Nanogels are internally crosslinked particles of nanometric size used in various fields e.g. as such as carriers in drug delivery systems. They can be produced using ionizing radiation in dilute aqueous solutions. This method is carried out in a pure polymer-solvent system, avoiding the addition of any additives such as monomers, surfactants, catalysts and crosslinking agents and no further purification step is necessary. Poly(N-vinyl pyrrolidone) (PVP K-90) nanogels were prepared by gamma irradiation in an aqueous solution. The samples were prepared in triplicate in multipurpose cobalt-60 gamma irradiator using 1, 10, 25 and 100 mM PVP solutions. Samples were irradiated in argon and nitrous oxide conditions with doses from 1 kGy up to 25 kGy with 10 kGy/h dose rate. The mean particle size (Rh) was determined by Dynamic Light Scattering (DLS) and radius of gyration (Rg) and weight-average molecular weight (Mw) by Static Light Scattering (SLS). These samples were morphologically characterized using Atomic Force Microscopy (AFM) and Transmission Electron Microscopy (TEM). Samples prepared with 100 mM PVP K-90 solution formed macroscopic gels, in the samples obtained with 25 mM PVP K-90 solution there was a prevalence of intermolecular crosslinking. On the other hand, in the samples generated with 10 mM PVP K-90 solution, there was a predominance of intramolecular crosslinking demonstrated in the tendency to: decrease in the radius of gyration (Rg), in the constancy of the weight-average molecular weight (Mw), in the increase in polymer coil density (ρcoil), in the Rg/Rh ratio (shape factor) around 1.0 indicating homogenous, internally cross-linked spheres, in the high relief spherical structures observed in the AFM images and in the spherical particles with high contrast observed in the TEM images. The saturation of the samples with nitrous oxide doubled formation of hydroxyl radicals, favoring the generation of polymeric radicals. Higher average number of radicals in each macromolecule contributed to the higher number of intramolecular crosslinks.

Obesity and social representations among patients subjected to argon plasma coagulation (APC) / Obesidade e representações sociais entre pacientes submetidos à coagulação de plasma de argônio (APC) / Obesidad y representaciones sociales entre pacientes sujetos a coagulación de plasma de argón (APC)

This study sought to identify the Social Representations of Obesity among 15 individuals who underwent bariatric surgery through the Roux-en-Y Gastric Bypass (RYGB) method and were subjected to Argon Plasma Coagulation (APC) due to weight relapse. Data were collected through interviews and analyzed via Descending Hierarchical Classification. Obesity was associated with physical limitations and difficulties in social relationships. Prejudice and difficulty in changing habits are associated with the choice to undergo surgical treatment and to weight relapse. The suffering that goes along with obesity and the difficulty in changing habits seem to be associated with the search for surgical help.

Este estudo procurou identificar as representações sociais da obesidade entre 15 indivíduos submetidos à cirurgia bariátrica pelo método Bypass Gástrico em Y de Roux (RYGB) e submetidos à Coagulação por Plasma de Argônio (APC) devido à recidiva de peso. Os dados foram coletados através de entrevistas e analisados por meio da Classificação Hierárquica Descendente. A obesidade foi associada a limitações físicas e dificuldades nas relações sociais. Preconceito e dificuldades na mudança de hábitos estão associados à escolha de se submeter a tratamento cirúrgico e à recidiva de peso. O sofrimento que acompanha a obesidade e a dificuldade de mudar hábitos parecem estar associados à busca de ajuda cirúrgica.

Este estudio buscó identificar las representaciones sociales de la obesidad entre 15 individuos que se sometieron a cirugía bariátrica utilizando el método de bypass gástrico Roux-en-Y (RYGB) y que se sometieron a coagulación con plasma de argón (APC) debido a una recaída en el peso. Los datos fueron recolectados a través de entrevistas y analizados utilizando la Clasificación Jerárquica Descendente. La obesidad se asoció con limitaciones físicas y dificultades en las relaciones sociales. Los prejuicios y las dificultades para cambiar los hábitos están asociados con la opción de someterse a un tratamiento quirúrgico y una recaída del peso. El sufrimiento que acompaña a la obesidad y la dificultad para cambiar los hábitos parecen estar asociados con la búsqueda de ayuda quirúrgica.

Endoscopic Band Ligation Versus Argon Plasma Coagulation in the Treatment of Gastric Antral Vascular Ectasia: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

BACKGROUND/AIMS: Argon plasma coagulation (APC) is the most commonly used endoscopic treatment for gastric antral vascular ectasia (GAVE). Endoscopic band ligation (EBL) has emerged as an alternative therapy. Our goal was to evaluate the feasibility, efficacy, and safety of APC and EBL for the treatment of GAVE. This is the first systematic review that included only randomized controlled trials (RCTs) on this topic. METHODS: A comprehensive search was performed using electronic databases to identify RCTs comparing APC and EBL for the treatment of GAVE following the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. RESULTS: Four RCTs were included, with a total of 204 patients. EBL was related to higher endoscopic eradication rates risk difference [RD], 0.29; 95% confidence interval [CI] [0.14, 0.44]; I2=0%) and less bleeding recurrence than APC (RD, 0.29; 95% CI [0.15, 0.44]; I2=0%). Patients treated with EBL required fewer blood transfusions (mean difference [MD], 1.49; 95% CI [0.28, 2.71]; I2=96%) and hospitalizations (MD, 0.29; 95% CI [0.19, 0.39]; I2=0%). The number of sessions required for the obliteration of lesions was higher with APC. There was no difference in the incidence of adverse events. CONCLUSION: EBL is superior to APC in the treatment of GAVE in terms of endoscopic eradication rates, recurrence of bleeding, and transfusion requirements.

Effect of argon plasma on repair bond strength using nanofilled and microhybrid composites.

OBJECTIVES: To evaluate the effect of atmospheric pressure plasma (PLA), sandblasting (SAN), silanization (SIL) and hydrophobic bonding resin (HBR) on the micro-shear bond strength (MSBS) of fresh nanofilled (NF) or microhybrid (MH) composites to water-aged nanofilled composite. MATERIALS AND METHODS: NF plates were fabricated and stored in distilled water for 4 months. The aged plates were assigned to the groups (n = 6): 1- untreated; 2- SAN + SIL + HBR; 3- HBR; 4- PLA + HBR; 5- SAN + HBR; 6- SAN + PLA + HBR; and 7- PLA. Two fresh composite cylinders were constructed on each plate with NF or MH composites and tested after 24 h or 1 year of water-storage, using the MSBS testing. Data were analyzed by three-way ANOVA and Tukey test (α = 0.05). RESULTS: NF yielded better outcomes than MH at 24 h, which was not observed at 1 year. HBR showed the highest MSBS results, while untreated and PLA groups yielded the lowest one. MSBS reduced for all groups after 1 year. CONCLUSIONS: Only HBR can obtain good MSBS results, while PLA alone was not beneficial. After 1 year, a reduction in repair MSBS was observed and the type of composite did not influence the results. CLINICAL RELEVANCE: The repair technique can be simplified with the use of only an adhesive and macromechanical retentions in the old composite, regardless the type of fresh composite.

El Hybrid-APC en el tratamiento endoscópico del esófago de Barrett / The Hybrid-APC in the endoscopic treatment of Barrett'sesophagus

RESUMEN Fundamento: debido al riesgo de evolución insatisfactoria de los pacientes con esófago de Barrett hacia el adenocarcinoma esofágico, es necesaria la aplicación de técnicas seguras y efectivas que logren prevenir el desenlace hacia lesiones malignas esofágicas. El Hybrid-APC (Argón plasma coagulación) es una de estas técnicas que permiten detener la historia natural del esófago de Barrett en su etapa inicial. Objetivo: realizar una revisión y reflexión acerca del tratamiento endoscópico del esófago de Barrett con el Hybrid-APC. Métodos: se realizó una búsqueda en los motores Google, PudMed, SciELO regional, SciELO Public Health, National Library of Medicine PudMed. En la estrategia de la búsqueda se utilizaron los términos: esófago de Barrett, tratamiento endoscópico, Hybrid-APC. Se evaluaron los documentos en extensos y se desarrolló un documento resumen de la información recolectada. En la búsqueda bibliográfica realizada se encontraron 20 trabajos relacionados con esófago de Barrett, tratamiento endoscópico 10 y específico del uso del Hybrid-APC cinco. Resultados: los estudios reportaron la efectividad y seguridad de la ablación con el Hybrid-APC en el tratamiento endoscópico del esófago de Barrett con displasia de bajo grado; y en la displasia de alto grado y carcinoma in situ remanente, luego de una resección mucosa endoscópica. Conclusiones: el tratamiento endoscópico del esófago de Barrett con Hybrid-APC, se considera una técnica alternativa para detener la evolución de esta enfermedad hacia el adenocarcinoma. Esto generará motivación para entrenamientos y su puesta en práctica de forma generalizada.

ABSTRACT Background: due to the risk of unsatisfactory evolution of patients with Barrett's esophagus (EB) towards esophageal adenocarcinoma, it is necessary to apply safe and effective techniques that prevent the outcome towards esophageal malignant lesions. The Hybrid-APC (argon plasma coagulation) is one of these techniques that allow stopping the natural history of EB in its initial stage. Objective: to conduct a review and reflection on the endoscopic treatment of Barrett's esophagus with the Hybrid-APC. Methods: a search was conducted on Google, PudMed, SciELo regional, SciELo Public Health, National Library of Medicine PudMed engines. The search strategy used the terms: Barrett's esophagus, endoscopic treatment, Hybrid-APC. Extensive documents were evaluated and a summary document of the information collected was developed. The literature search found 20 works related to Barrett's esophagus, ten on endoscopic treatment, and five on specific to the use of Hybrid-APC. Results: studies reported the effectiveness and security of the ablation with the Hybrid-APC in the endoscopic treatment of Barrett's esophagus with low degree dysplasia, and in the high degree dysplasia and remnant carcinoma in situ, after the endoscopic mucous resection. Conclusions: the endoscopic treatment of Barrett's esophagus with Hybrid-APC is considered an alternative technique to stop the evolution of this pathology towards adenocarcinoma. This will generate motivation for training and its implementation in a generalized way.

Argon Atmospheric Plasma Treatment Promotes Burn Healing by Stimulating Inflammation and Controlling the Redox State.

Burns are a public health problem, with second-degree burns as one of the most common types. Although intense inflammation worsens burn healing, effective therapies are scarce. Thus, infections and hypertrophic scars may occur, which compromise patient quality of life and may delay healing. Argon atmospheric plasma (AP) has been shown to positively influence wound healing. In the context of identifying effective and alternative therapies for the treatment of second-degree burns, the present study evaluated AP in the treatment of second-degree burns in rats compared to that for sham treatment on the 2nd, 7th, 14th, and 21st days post-injury. Our results revealed proinflammatory effect for AP by recruiting predominantly neutrophils on the 7th day and macrophages on the 21st day compared to sham treatment, allowing a greater production of interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, and IL-17, and also controlled the inflammation by IL-10 and transforming growth factor (TGF)-ß1. AP also showed antioxidant activity important for controlling oxidative damage on the 2nd day. This favored the induction of angiogenesis from the 2nd day and induction fibroplasia and fibrillogenesis after the 14th day, which enhanced burn healing with the formation of a thinner burn eschar before the 21st day post-burn. Thus, AP effectively modulated the inflammatory phase of second-degree burn healing through the control of oxidative damage that favored the following phases. Therefore, AP is a relevant alternative in the treatment of second-degree burns.

Aplicação de plasma de argônio endoscópico para tratamento do reganho de peso após cirurgia bariátrica em uma clínica privada de Florianópolis / Using of endoscopic argon plasma for treatment of weight regain after bariatric surgery in a private clinic in Florianópolis

Introdução: Atualmente o bypass gástrico em Y de Roux (BGYR) é o método cirúrgico de escolha no tratamento da obesidade. Todavia, pode ocorrer reganho de peso após a cirurgia. A aplicação do plasma de argônio por via endoscópica constitui uma opção terapêutica que visa redução do calibre da anastomose gastrojejunal, com consequente perda de peso. Objetivo: Avaliar a relação da redução do calibre da anastomose gastrojejunal com a perda de peso e sensação de saciedade nos pacientes que readquiriram peso após BGYR. Métodos: Estudo observacional transversal, que incluiu 34 pacientes submetidos à aplicação do plasma de argônio entre 2014 e 2018, na Usuy Clínica Médica em Florianopólis. As diferenças entre as médias de peso, IMC e diâmetro da anastomose gastrojejunal frente a aplicação do plasma de argônio e saciedade referida foram estabelecidas pelo teste de Wilcoxon (p≤0,05). Resultados: Observou-se redução de 6,26% do peso, 6,21% do IMC e 43,04% do diâmetro anastomótico comparando as médias pré e pós seis meses do procedimento. 53,3% dos pacientes sentiram-se mais saciados. Conclusão: A aplicação do plasma de argônio mostrou-se eficaz na redução do diâmetro da anastomose gastrojejunal, perda de peso corporal e diminuição do IMC.

Introduction: Nowadays the Roux-en-Y Gastric Bypass (RYGB) is the surgical choice method in obesity treatment. However, weight regain may occur after the surgery. The endoscopy applied argon plasma constitutes one therapeutic option in order to reduce the gastrojejunal anastomosis caliber and consequently weight loss. Objective: To evaluate the relation between the gastrojejunal anastomosis caliber reduction, weight loss and sensation of satiety in patients who regained weight after RYGB. Methods: Observational cross-sectional study that includes 34 patients submitted to argon plasma application between 2014 and 2018 at the Usuy Medical Center in Florianopolis. Weight averages, Body Mass Index (BMI) and gastrojejunal anastomosis diameter differences regarding argon plasma application and referred satiety were established by the Wilcoxon Test (p ≤ 0,05). Results: A reduction of 6.26 % of the weight, 6.21 % of the BMI and 43.04 % of the anastomotic diameter was observed upon comparing the average rate six months before and after the procedure. 53.3 % of the patients felt more satiated. Conclusion: The argon plasma application was effective in reducing gastrojejunal anastomosis diameter, body weight and BMI.

[A probable fatal argon gas embolism during resection of a cutaneous biliary fistula - a case report]. / Provável embolia letal por gás argônio durante ressecção de fístula cutânea biliar ­ relato de caso.

BACKGROUND: The Argon Beam Coagulator (ABC) achieves hemostasis but has potential complications in the form of argon gas embolisms. Risk factors for embolisms have been identified and ABC manufacturers have developed guidelines for usage of the device to prevent embolism development. CASE REPORT: A 49 year-old male with history of recurrent cholangiocarcinoma status post resection presented for resection of a cutaneous biliary fistula. Shortly after initial use of the ABC, the patient underwent cardiac arrest. After resuscitation, air bubbles were observed in the left ventricle via Transesophageal Echo (TEE). CONCLUSION: Although argon embolisms have been described more commonly during laparoscopies, this patient most likely experienced an argon gas embolism during an open resection of a cutaneous biliary fistula via the biliary tract or vein with possible transpulmonary passage of the embolism. Consequently, a high degree of suspicion should be maintained for an argon gas embolism during ABC use in laparoscopic, open, and cutaneous surgeries.