Biocompatibility Assessment of Poly(lactic acid) Films after Sterilization with Ethylene Oxide in Histological Study In Vivo with Wistar Rats and Cellular Adhesion of Fibroblasts In Vitro

Biomaterials must meet certain fundamental requirements for their usage in living beings, such as biocompatibility, bifunctionality, and sterilizability, without having chemical and structural changes. The biocompatibility of poly(lactic acid) (PLA) films, shaped by compression, was evaluated after sterilization by ethylene oxide by a histological in vivo test with Wistar rats and cytotoxicity in cell adhesion in vitro. The cytotoxicity test was performed by the reduction of tetrazolium salt (MTT). Thermal and chemical changes in PLA films concerning the proposed sterilization process and characteristics were not observed to evidence polymer degradation due to sterilization. The analysis of the cytotoxicity by the MTT method has shown that the sterilized PLA films are not cytotoxic. The adhesion and proliferation of fibroblasts on PLA films were homogeneously distributed over the evaluation period, showing an elongated appearance with unnumbered cytoplasmic extensions and cell-cell interactions. By examining the biocompatibility in a histological study, a mild tissue inflammation was observed with the presence of fibrosis in the samples that had been exposed for 21 days in the rats’ bodies. PLA films sterilized with ethylene oxide did not exhibit cell adhesion in vitro and toxicity to the surrounding tissue in vivo and they may be used in future in vivo testing, according to histological findings in Wistar rats in the present study

Indkomne bøger fra oktober 1999 til september 2000

Head and neck cancer (HNC) has a high incidence in Brazil, with cancer of the oral cavity being one of the five most common cancers among Brazilians. Alcohol and tobacco consumption may contribute to synchronous or metachronous HNC and esophageal cancer. The early detection of superficial esophageal cancer and dysplasia in asymptomatic patients with HNC, after successfully treating the primary cancer, may provide an effective cure. A prospective study involving 60 patients with HNC was carried out at the State University of Campinas (UNICAMP) to screen for superficial esophageal cancer and dysplasia using endoscopy and a 2% lugol dye solution followed by biopsy of the suspicious areas. Five patients (8.3%) had superficial esophageal cancer, which was diagnosed as intraepithelial carcinoma in three of them (5.0%). In four patients, the superficial esophageal cancer was synchronous, and in one it was metachronous to HNC. Five patients (8.3%) had dysplasias in the esophageal epithelium (three were classified as mild and two as moderate). These results demonstrate the value of endoscopic screening of the esophagus using lugol dye in patients with HNC, particularly because superficial esophageal cancer is extremely difficult to detect by conventional methods in asymptomatic patients.22170-

Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

Videolaparoscopic surgical treatment of gastroesophageal reflux disease: modified Nissen technique - clinical and functional results

BACKGROUND: Gastroesophageal reflux disease is highly common worldwide and surgical treatment is being indicated more frequently. Currently, laparoscopic is the access of choice and several antireflux techniques may be used. We prefer a modified Nissen technique. PURPOSE: To analyze preoperative clinical and functional parameters and compare with postoperative outcome of a modified valve technique performed by laparoscopy. METHODS: A group of 59 patients underwent laparoscopic modified Nissen valve. Preoperative diagnosis was made by radiological contrast exams and endoscopy in all patients. Esophagus manometry was performed in 35 patients and scintigraphy scan in 15 patients. Complicated esophagitis occurred in 54.2%, with 21 (35.6%) patients presenting a Barrett's epithelium. Laparoscopic surgery was performed in all patients with no conversion to open surgery, with an average time of 123.9 minutes. RESULTS: There were no intraoperative complications. Hospital discharge occurred in an average of 47.6 hours. Symptoms as dysphagia, pain, regurgitation and flatus occurred in 48.1% of the patients in the first thirty days. Average follow-up was 20.8 months. Postoperative radiological, endoscopic, manometric and scintigrafic scan exams showed a significant improvement, as well as clinical assessment using Visick's classification, which showed excellent and good results in 93.1% of the patients. CONCLUSION: Comparative analysis of clinical assessment and exam results lad us to conclude that modified Nissen surgery by laparoscopic access corrects gastroesophageal reflux in most patients followed-up.A doença do refluxo gastroesofagiano é muito freqüente na população e o tratamento cirúrgico é indicado em um número respeitável de pacientes. A escolha da via de acesso é a laparoscopia. Várias técnicas anti-refluxo podem ser empregadas e preferimos a técnica de Nissen modificada. OBJETIVO: Analisar os parâmetros clínicos e funcionais pré-operatórios comparados com os mesmos parâmetros pós-operatórios com a técnica empregada. MÉTODOS: Um grupo de 59 pacientes foi submetido a tratamento cirúrgico pela técnica de Nissen modificada videolaparoscópica. O diagnóstico pré-operatório foi feito por exame radiográfico contrastado e endoscopia digestiva alta em todos os pacientes. A manometria do esôfago realizada em 35 e a cintilografia em 15. Esofagite complicada ocorreu em 54,2% sendo 21 pacientes (35,6%) com epitélio de Barrett. A técnica cirúrgica laparoscópica foi concluída em todos os pacientes. O tempo médio de cirurgia foi de 123,9 minutos. RESULTADOS: Não ocorreram complicações intra-operatórias. A alta se deu em média com 47,6 horas. Sintomas de disfagia, dor, epigastralgia, regurgitação e flatulência até o 30° dia ocorreram em 48,1% dos pacientes. Ocorreu uma reoperação por recurrência da doença e um óbito por necrose do fundo gástrico. O seguimento médio foi de 20,8 meses. Os exames pós-operatórios radiográficos, endoscópicos, manométricos e de cintilografia mostraram melhora significativa, bem como a avaliação clínica, que mostrou excelentes e bom resultados em 93,1% dos pacientes. CONCLUSÃO: A cirurgia de Nissen modificada videolaparoscópica corrigiu a doença do refluxo gastroesofagiano na maioria dos doentes acompanhados, associada à baixa morbimortalidade.14114