Chemical characterization (LC-MS-ESI), cytotoxic activity and intracellular localization of PAMAM G4 in leukemia cells.

Generation 4 of polyamidoamine dendrimer (G4-PAMAM) has several biological effects due to its tridimensional globular structure, repetitive branched amides, tertiary amines, and amino-terminal subunit groups liked to a common core. G4-PAMAM is cytotoxic due to its positive charges. However, its cytotoxicity could increase in cancer cells due to the excessive intracellular negative charges in these cells. Furthermore, this work reports G4-PAMAM chemical structural characterization using UHPLC-QTOF-MS/MS (LC-MS) by electrospray ionization to measure its population according to its positive charges. Additionally, the antiproliferative effects and intracellular localization were explored in the HMC-1 and K-562 cell lines by confocal microscopy. The LC-MS results show that G4-PAMAM generated multivalent mass spectrum values, and its protonated terminal amino groups produced numerous positive charges, which allowed us to determine its exact mass despite having a high molecular weight. Additionally, G4-PAMAM showed antiproliferative activity in the HMC-1 tumor cell line after 24 h (IC50 = 16.97 µM), 48 h (IC50 = 7.02 µM) and 72 h (IC50 = 5.98 µM) and in the K-562 cell line after 24 h (IC50 = 15.14 µM), 48 h (IC50 = 14.18 µM) and 72 h (IC50 = 9.91 µM). Finally, our results showed that the G4-PAMAM dendrimers were located in the cytoplasm and nucleus in both tumor cell lines studied.

Assessment of bullet holes through the analysis of mushroom-shaped morphology in synthetic fibres: analysis of six cases.

Textiles damage analysis is a very valuable tool in forensic investigations. However, to date, very little research has been carried out to understand the impact of bullet causing damages to clothing. According to the review of the most recent scientific papers, the frictional heating and crushing action of a bullet passing through synthetic fibres cause a unique transformation in their ends called mushroom-shaped morphology. In this study, the textile remains of six individuals executed during the first decade of the Chilean military dictatorship period (1973-1990) were analysed. The purpose was to examine their clothing in order to describe the fibre defects in the bullet holes. The fibres were directly observed using two different models of stereomicroscopy (MZ16A and EZ4D, Leica Microsystem Ltd., Wetzlar, Germany) and through a combination of transmitted, oblique and co-axial illumination (with Leica DFC500 Digital Camera), at × 230 and at a resolution of up to 840 Lp/mm. The mushroom-shaped morphology, along with rupturing of yarns, fibrillation or splitting of fibres, was observed in the bullet holes. Although the mushroom-shaped is a useful pattern for bullet hole identification in synthetic fibres, further research needs to be performed for developing a sounder interpretational framework of this type of forensic evidence.

Avaliação in vitro de carga máxima de fratura em próteses fixas adesivas de resina composta indireta reforçadas com malha de sílica-nylon submetidas ao processo de envelhecimento / In vitro evaluation of maximum fracture load in resin-bonded fixed dental prostheses of indirect composite resin reinforced by silica-nylon mesh submitted to the aging process

O uso de próteses fixas adesivas é uma opção de tratamento reabilitador em casos de ausência dentária. A resina composta é um material com boas características mecânicas e estéticas, mas se faz necessário a utilização de reforços para proporcionar maior resistência ao conjunto. O presente estudo teve como objetivo avaliar a carga máxima de fratura quando da utilização de um sistema de reforço de sílica-nylon em próteses fixas adesivas confeccionadas em resina composta indireta. O estudo in vitro simulou uma prótese fixa adesiva de três elementos anterior (A) e posterior (P). Dessa forma, foram confeccionados 80 espécimes distribuídos em 8 grupos experimentais (n=10), tendo como variáveis a presença do sistema de reforço em sílica-nylon (R) e a ciclagem mecânica da peça protética (C). O processo de envelhecimento foi realizado através da ciclagem mecânica por 106 ciclos a 4 Hz (ERIOS ER-11000 Plus, São Paulo, Brasil). As amostras foram submetidas ao ensaio de resistência à carga máxima de fratura na máquina de ensaio universal (EMIC DL 1000, EMIC, Brasil) com uma célula de carga de 1000 Kgf e foram feitas análises das amostras após a fratura em estereomicroscópio (Discovery V20 CarlZeiss, Jena, Alemanha) e Microscopia Eletrônica de Varredura (Inspect S 50, FEI Company, Brno, República Tcheca). A análise estatística foi constituída pela análise de variância (ANOVA) e teste Tukey 5%. O estudo in silico foi realizado através da Análise em Elementos Finitos (FEA), onde os dentes pilares e as próteses foram escaneados (Ceramill Map 400, Amann Girrbach) e transferidos para o software CAD Rhinoceros (version 4.0SR8; McNeel North America, Seattle, WA), para elaboração do modelo volumétrico 3D e posteriormente a análise foi feita através do Software Ansys 19.3 (ANSYS, Inc. Southpointe, Canonsburg, EUA). Os resultados de resistência à carga máxima de fratura foram (N): A=163,55; AC=184,48; AR=198,81; ARC=192,24; P=539,99; PC=359,61; PR=541,74 e PRC=608,74. Foi constatado que houve diferença estatística na presença do reforço tanto nos grupos da região anterior (p=0,025), quanto da região posterior (p=0,001). Os resultados de tensão máxima principal, obtidos no FEA, foram (MPa): A=53,24/122,40; AR=55,07/117,70; P=33,28/36,18 e PR=28,06/42,87. Concluiu-se que a incorporação da malha de sílica-nylon aumentou a resistência à carga máxima de fratura das próteses fixas adesivas, independente da área em que se encontra, e os resultados obtidos no FEA corroboraram com os encontrados no teste in vitro o que permite concluir que houve validação do teste in silico(AU)

The use of resin-bonded fixed dental prostheses is a rehabilitative treatment option in cases of missing teeth. Composite resin is a material with good mechanical and aesthetic characteristics, but it is necessary to use reinforcements to provide greater resistance to the prosthesis. The present study aims to evaluate the maximum fracture load using a silica-nylon reinforcement system on resin-bonded fixed dental prostheses made of indirect composite resin. In vitro test simulated an anterior (A) and posterior (P) three-element resin-bonded fixed dental prostheses. Thus, 80 specimens were made in 8 experimental groups (n = 10), with variables the presence of the silica-nylon reinforcement system (R) and the mechanical cycling of the prosthesis (C). The aging process was performed through mechanical cycling for 106 cycles at 4 Hz (ERIOS ER-11000 Plus, São Paulo, Brazil). The samples were tested by maximum fracture load in the universal test machine (EMIC DL 1000, EMIC, Brazil) with a 1000 Kgf load cell and analyzed by stereomicroscope (Discovery V20 CarlZeiss, Jena, Germany) and Scanning Electron Microscopy (Inspect S 50, FEI Company, Brno, Czech Republic). Statistical analysis consisted of analysis of variance (ANOVA) and Tukey test 5%. In silico study was performed by Finite Element Analysis (FEA), where the abutment teeth and the prostheses were scanned (Ceramill Map 400, Amann Girrbach) and transferred to the CAD Rhinoceros (version 4.0SR8; McNeel North America, Seattle, WA) for the elaboration of the 3D volumetric model and the analysis test was made in the Ansys Software 19.3 (ANSYS, Canonsburg, PA, USA). The results of resistance to the maximum fracture load were (N): A=163,55; AC=184,48; AR=198,81; ARC=192,24; P=539,99; PC=359,61; PR=541,74 and PRC=608,74. It was found that there was a statistical difference in the presence of reinforcement in both the anterior region (p=0,025) and posterior region groups (p=0,001). The maximum main stress results obtained in the FEA were (MPa): A=53,24/122,40; AR=55,07/117,70; P=33,28/36,18 and PR=28,06/42,87. It was concluded that the incorporation of the silica-nylon mesh increased the resistance to maximum fracture load of the resin-bonded fixed dental prostheses regardless of the area it is located, and the results obtained in the FEA corroborated the results of in vitro test, which allows to conclude that the in silico test was validated(AU)

Marine debris in Trindade Island, a remote island of the South Atlantic.

Marine debris is widespread in oceans worldwide, including the most remote locations. Here, for the first time, we report macro-debris accumulation on beaches of Trindade Island, a remote island 1160 km from mainland Brazil. High debris density was recorded on windward, east-coast beaches, which are exposed to wind-driven currents. Small-sized plastic fragments were the most abundant debris. Polyethylene (67%), polypropylene (30%) and polyamide (3%) were the most prevalent polymeric materials identified by ATR-FTIR. Identified debris show that interaction with Trindade fauna, mainly with seabirds and endangered terrestrial crabs, exists and already has some impact. This study provides baseline information on Trindade macro-debris demonstrating that the island, located on the edge of the South Atlantic Gyre, acts as a sink for gyre debris, exposing the island fauna to the threats related to plastic contamination.

Microplastics on sandy beaches of the Baja California Peninsula, Mexico.

Microplastics have become a concern in recent years because of their negative impact on marine and freshwater environments. Twenty-one sandy beach sites were sampled to investigate the occurrence and distribution of microplastics on the sandy beaches of the Baja California Peninsula, Mexico, as well as their spectroscopic characterization and morphology. Microplastics were separated using the density method and identified using Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR-FTIR). The mean abundance of microplastics in the samples was 135 ±â€¯92 particles kg−1, and fiber was the most abundant microplastic found in the samples, comprising 91% of the total microplastics identified. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) analysis of the microplastics showed that the main polymers found in microplastics were polyacrylic, polyacrylamide, polyethylene terephthalate, polyesters, and nylon.

Evaluation of polyamide surgical mesh as an abdominal ventral implant in rabbits

Purpose: To evaluate abdominal ventral wound healing by using a specific biomaterial, a handmade polyamide surgical mesh. Methods: A surgical incisional defect was made in ten rabbits to simulate a hernia in the ventral abdominal musculature. A polyamide surgical mesh was used in hernioplasty. They were monitored for surgical wound healing, and macroscopically and histologically evaluated at the end of the experiment. The polyamide surgical mesh did not cause foreign body reaction, pain, edema, or infection in the surgical site. The manure production was not affected by intestinal tissue adherences to the mesh, consistent with the ultrasonography result where adherences were not observed and organized scarring tissue formed in the incisional defect. The polyamide mesh was fixed over the abdominal wall, and its external and internal sides were surrounded by a vascularized connective tissue. Results: None of the experimental animals developed adherences from internal organs to the polyamide mesh, except two rabbits where the omentum formed adherence to the internal scarring tissue without present herniation or compromise of the rabbits health. Conclusion: Polyamide surgical mesh for hernioplasty presents, in rabbits, excellent biocompatibility, with minimal body adverse reactions and low cost.(AU)

Comparação de resultado estético em cicatrizes com uso de fios cirúrgicos e Prineo® / Comparison between surgical sutures and Prineo® in terms of esthetic result and scar formation

Introdução: Cicatrização de ferida é um processo bem organizado que tem como finalidade a reparação tecidual completa. Colas e adesivos tópicos oferecem uma alternativa não invasiva, de retirada fácil e espontânea; boa força tênsil; menor tempo de aplicação, sendo o Prineo® uma cola adesiva associada a uma malha de poliéster aplicados sobre a ferida. Método: Trata-se de um estudo transversal retrospectivo com análise de 101 procedimentos cirúrgicos no período de 2012 a 2014, nos quais a síntese da ferida operatória ocorreu com fios cirúrgicos de náilon ou Prineo®, sendo aplicada análise estatística. Resultados: Neste estudo, seis pacientes apresentaram dermatite de contato ao uso do Prineo® com significância estatística (p = 0,042). O uso desse sistema diminuiu a taxa de alargamento cicatricial (p < 0,05). O presente trabalho não apresentou diferença estatística (p = 0,068) na qualidade da cicatriz entre os pacientes que utilizaram Prineo® em relação ao grupo controle, demonstrando que em ambos os grupos o resultado cicatricial foi de excelente (87%) a bom (27%) na sua maioria. Conclusão: Conclui-se no estudo que os pacientes que utilizaram o sistema de octil-2-cianocrilato associado a malha, Prineo®, apresentaram menores índices de alargamento cicatricial, dependentes de uma espessura de derme satisfatória, e maiores taxas de dermatites por contato em relação àqueles em que a ferida foi encerrada com fios cirúrgicos. Os dois grupos demonstraram qualidades cicatriciais excelentes a bons, sem diferença estatística em tais resultados estéticos cicatriciais.

Introduction: Wound healing is a well-organized, directed process of tissue repair. The process can be expedited using topical glues and adhesives, which offer a non-invasive, easily removable alternative to suturing. Furthermore, such products have good tensile strength and involve lower application time. In particular, the Prineo® adhesive is applied to a polyester mesh that covers the wound. Method: We carried out a retrospective, cross-sectional study, with subsequent statistical analysis , involving 101 surgical procedures in which wound closure was performed using either nylon sutures or Prineo®. All the procedures were performed between 2012 and 2014. Results: Six patients had contact dermatitis after Prineo® was used, with statistical significance (p = 0.042). Furthermore, Prineo® decreased the rate of scar enlargement (p < 0.05) . There was no statistical difference between the Prineo® and suture groups in terms of scar quality (p = 0.068); in both groups, the scar result was mostly excellent (87 %) to good (27%). Conclusion: Patients whose wounds were closed using Prineo® a system involving octyl-2-cyanoacrylate and an associated polyester mesh displayed lower rates of scar enlargement, which depended on whether the thickness of the dermis was satisfactory. However, the same patients had higher rates of contact dermatitis than those whose wounds were closed using surgical sutures. Both groups showed excellent to good scar quality, with no significant difference in terms of esthetic scar results.

Reação tipo corpo estranho a preenchimento facial com poliamida / Foreign body reaction to polyamide filling in the face

O uso de substâncias para preenchimento dérmico é crescente, e o número de complicações devido à sua utilização, significativo. Neste trabalho, relatamos um caso de granulomas de corpo estranho após preenchimento facial com gel de poliamida, chamado AqualiftTM, produto não encontrável nas bases de dados da literatura científica. São discutidos aspectos clínicos, terapêuticos e histopatológicos. Faz-se uma advertência relativa ao uso desta substância.

Dermal fillers are increasingly used, and the number of complications due to their use is significant. In this work, we report the case of foreign body granulomas due to the facial injection of a polyamide gel, named AqualiftTM, a product not found in scientific literature databases. Clinical, therapeutic and hystopathological aspects are discussed. A warning is made, concerning the use of this substance.

Continuous absorbable suture versus interrupted permanent suture in the treatment of diastasis of the rectus abdominis muscle / Sutura contínua com fio absorvível versus interrompida com fio permanente no tratamento da diástase do músculo reto abdominal

Introduction: Plication of the rectus abdominis muscle is an important step in remodeling the abdomen in abdominoplasties. It can be performed using several types of threads with interrupted or continuous sutures, according to the surgeon's preferences. Few studies in the literature compared the different plication techniques in abdominoplasties. The present study aimed to compare continuous anchored suture with polydioxanone (PDS) with interrupted nylon suture regarding surgical time, relapse, and costs and discuss the advantages and disadvantages of each method. Methods: A randomized clinical trial in which 30 patients were enrolled for each of the two groups, 15 with continuous suture and 15 with interrupted suture, was conducted. The plication time was compared between the groups using the Student's t-test. Between 10 and 12 months postoperatively, all patients underwent ultrasonography for investigating diastasis recurrence. Results: Continuous suture decreased the plication time by almost 40% when compared to the interrupted suture (p < 0.001), without affecting the esthetic outcome. The PDS used in the continuous suture implied higher costs than those with the nylon threads used in the interrupted suture. No recurrence was found on the postoperative control ultrasonography results. Conclusion: Continuous suture reduced the plication time by almost 40% (p < 0.001) when compared to interrupted suture. Despite being associated with higher costs, PDS seems to be a good alternative to non-absorbable sutures, such as nylon threads, in plications of the rectus abdominis, since it is a more biocompatible material.

Introdução: A plicatura do músculo reto abdominal é um passo importante no remodelamento do abdômen nas abdominoplastias. Ela pode ser realizada com vários tipos de fios e com suturas interrompidas ou contínuas, de acordo com as preferências do cirurgião. Poucos estudos na literatura compararam diferentes técnicas de plicatura nas abdominoplastias. O objetivo do estudo é comparar a sutura contínua ancorada com polidioxanona (PDS) com a sutura interrompida com náilon quanto ao tempo cirúrgico, recidiva, custos e discutir vantagens de desvantagens de cada método. Métodos: Ensaio clínico randomizado no qual 30 pacientes foram arroladas para cada um dos grupos, 15 sutura contínua e 15 sutura interrompida. O tempo de plicatura foi comparado entre os grupos utilizando-se o teste t de Student. Entre 10 a 12 meses de pós-operatório, todas as pacientes foram submetidas à ecografia em busca de recidivas da diástase. Resultados: A sutura contínua diminuiu em quase 40% o tempo de plicatura quando comparada à sutura interrompida (p < 0,001), sem prejuízo no resultado estético. O PDS utilizado na sutura contínua implicou maiores custos que os fios de náilon utilizados na sutura interrompida. Nenhuma recidiva foi encontrada na ecografia de controle no pós-operatório. Conclusão: A sutura contínua quando comparada à sutura interrompida foi capaz de reduzir o tempo de plicatura em quase 40% (p < 0,001). A utilização do PDS, apesar dos maiores custos, parece ser uma boa alternativa às suturas com fios não absorvíveis como o náilon nas plicaturas do músculo reto abdominal, uma vez que se trata de um fio de maior biocompatibilidade.

Evaluation of the abdominal wall cicatrization of rabbits exposed to nicotine and undergone abdominoplasty using nylon thread or cyanoacrylate / Avaliação da cicatrização da parede abdominal de coelhos expostos à nicotina e submetidos à abdominoplastia, utilizando-se nylon ou cianocrilato

PURPOSE: To compare the wound healing of the abdominal wall of rabbits exposed to nicotine and submitted to abdominoplasty using 2-octyl cyanoacrylate or nylon thread for the surgery suture. METHODS: Thirty two rabbits were used. They were divided in subgroups: A1, A2, B1 e B2. Group A received saline 0.9%; group B received nicotine, both groups for 14 days before surgery. We performed an abdominoplasty with a nylon suture into the A1 and B1 subgroups; as for A2 and B2 groups the suture was performed with cyanoacrylate. The euthanasia happened in the 14th post-operative day. After, we evaluated: swollen process, fibroblast proliferation, collagen, neovascularization, and macroscope and microscope epithelization of the scars. RESULTS: We observed the presence of eosinophils in all scars exposed to the cyanoacrylate, and a significant increase of neovascularization in the subgroup B2 comparing to the A2 one (p=0.037). The other variables haven't showed any statistical difference. CONCLUSIONS: Nicotine hasn't influenced the swollen process, the fibroblast proliferation, the presence of collagen, neither the epithelialization. The neovascularization showed cicatricial immaturity when comparing group A2 to group B2. The eosinophils in the scars repaired with glue showed that the substance has acted as an allergen.(AU)

OBJETIVO: Comparar a cicatrização da parede abdominal de coelhos expostos à nicotina e submetidos à abdominoplastia utilizando 2-octil cianoacrilato ou nylon na síntese cirúrgica. MÉTODOS: Utilizou-se 32 coelhos. Estes foram distribuídos em subgrupos: A1, A2, B1 e B2. O grupo A recebeu solução de NaCl 0,9%; o B recebeu nicotina, ambos durante 14 dias do pré-operatório. Nos subgrupos A1 e B1 foi realizada abdominoplastia e sutura com "nylon"; enquanto A2 e B2 a síntese ocorreu com cianoacrilato. A eutanásia ocorreu no 14º dia do pós-operatório. Na pesquisa avaliou-se: processo inflamatório, proliferação fibroblástica, colágeno, neovascularização, epitelização macro e microscópica das cicatrizes. RESULTADOS: Observou-se presença de eosinofilia em todas as cicatrizes expostas ao cianoacrilato, e aumento significativo da neovascularização no subgrupo B2 em comparação com o A2 (p=0,037). Demais variáveis não apresentaram diferença estatística. CONCLUSÕES: A nicotina não influenciou o processo inflamatório, a proliferação fibroblástica, a presença de colágeno e a epitelização. A neovascularização indicou imaturidade cicatricial na comparação dos grupos A2 e B2. A eosinofilia nas cicatrizes reparadas com cola indica que a substância atuou como alergeno.(AU)

The seasonal and spatial patterns of ingestion of polyfilament nylon fragments by estuarine drums (Sciaenidae).

INTRODUCTION: Artisanal fisheries in tropical estuaries are an important economic activity worldwide. However, gear (e.g. ropes, nets, buoys, crates) and vessels are often in use under dangerous conditions. Polyfilament nylon ropes are used until they are well beyond human and environmental safety limits. Severe wear and tear results in the contamination of the environment with micro-fragments. The spread of these fragments in the marine environment and their ingestion by the biota are documented in the scientific literature and are increasing concerns. The aim of this study was to evaluate the ingestion of plastic fragments by two fish (drum) species in relation to seasonal, habitat and fish size-class variation. MATERIALS AND METHODS: The stomach contents of 569 individuals of Stellifer brasiliensis and Stellifer stellifer from the main channel of the Goiana Estuary were examined to identify variation in the number and the weight of plastic fragments and relate this variation to differences among the seasons (early dry, late dry, early rainy and late rainy), the habitats within the estuary (upper, middle and lower) and the size classes of the fish (juveniles, sub-adults and adults). RESULTS: Plastic fragments were found in 7.9% of the individuals of these two drum species captured from December 2005 to August 2008. Nylon fragments occurred in 9.2% of S. stellifer and 6.9% of S. brasiliensis stomachs. The highest number of nylon fragments ingested was observed in adults during the late rainy season in the middle estuary. DISCUSSION: Blue polyfilament nylon ropes are used extensively in fisheries and can be lost, inappropriately discarded or damaged during use in the estuary. These fragments were the only type of plastic detected during this study. The ingestion of nylon fragments by fish probably occurred during the animals' normal feeding activities. During the rainy season, the discharge of freshwater transports nylon fragments to the main channel and makes the fragments more available to fish. Fishery activities are responsible for a significant amount of the marine debris found in the estuary. CONCLUSIONS: The ingestion of fragments of nylon threads by fish is a demonstrated form of pollution in the Goiana Estuary. The physiological and toxicological consequences of the ingestion of this type of debris are unknown, as is the actual extent of the problem worldwide. The solutions to the problem are in the hands of authorities and communities alike because the good care and timely replacement of gear requires education, investment and effective policies.

Estudo clínico e histopatológico da reação tecidual às suturas interna e externa dos fios monofilamentares de nylon e poliglecaprone 25 em ratos / Clinical and histopathological study of tissue reactivity to monofilament suture materials: nylon and poliglecaprone 25 in rats

OBJETIVOS: Neste estudo realizamos a análise clínica e histopatológica da reação tecidual dos fios de nylon e poliglecaprone 25 monofilamentares nas suturas interna e externa em ratos. MÉTODOS: Foram utilizados 40 Rattus norvegicus (Wistar) machos. O ato operatório consistiu de incisão e divulsão dos planos muscular e cutâneo realizadas na região posterior das coxas dos animais. As suturas internas e externas da coxa direita foram realizadas com o fio de nylon nº5-0, e na coxa esquerda aplicamos o poliglecaprone 25 nº5-0. Os animais foram divididos em 4 grupos (n=10) de acordo com o tempo pós-operatório G1 (7 dias), G2 (14 dias), G3 (21 dias) e G4 (28 dias). Para a avaliação cínica foi considerada a ocorrência de deiscência, de exsudato e edema. Na análise histopatológica objetivou-se avaliar reação inflamatória, células gigantes de corpo estranho, proliferação fibroblástica e fibrose. RESULTADOS: Clinicamente, não foram observadas alterações nos grupos estudados. Histopatologicamente a reação inflamatória, presença de células gigantes de corpo estranho, proliferação fibroblástica e fibrose foram maiores nas suturas internas realizadas com Nylon. Nas suturas realizadas com poliglecaprone 25 essa reação declinou com o passar do tempo pós-operatório. CONCLUSÃO: De acordo com a metodologia empregada podemos concluir que as suturas externas realizadas com nylon induziram menor reação tecidual, enquanto que nas suturas internas este fio contribuiu para perpetuar a reação tecidual. As suturas externas realizadas com poliglecaprone 25 apresentaram maior reação tecidual, e suturas internas realizadas com o mesmo fio a reação tecidual declinou na medida em que o fio estava sendo absorvido. (AU)

PURPOSE: The aim of this experimental study was to evaluate through a clinical and histopatological analysis the tissue reactivity caused by two monofilament sutures nylon and poliglecaprone 25 on the internal and external sutures in rats.METHODS: For this study, we used forty male Rattus novergicus (Wistar rats). The experimental procedures were incisions and divulsions performed on the back of the animals' thighs. Internal and external sutures were done on the right thigh using nylon 0-5, and on the left thigh using poliglecaprone 25 0-5. The animals were distributed in 4 groups of 10 rats, according postoperatory period on the 7, 14, 21 and 28 days, G1 (7th day), G2 (14th day), G3 (21th day) and G4 (28th day). The clinical assentment aimed to verify the existence of deiscence, exsudate and edema. The histopathologic analisy's was intended to eveluate the inflammatory reaction, foregin body giant cells, fibroblastic proliferation and fibrosis.RESULTS: Clinically, no changes were found on groups studied. Histopathological analysis inflammatory reaction, foregin body giant cells, fibroblastic proliferation and fibrosis were higher on the internal sutures with nylon. On the sutures done with poliglecaprone 25 showed an increase in tissue reactivity passing postoperatory period.CONCLUSIONS: On the basis of the methodology used in the study, it was concluded that external sutures done with nylon produce less tissue reactivity; on internal sutures, however, this material contributes to the maintenance of the tissue reaction. The external sutures done with poliglecaprone 25 showed a greater tissue reaction; on the external sutures the tissue reaction decreased while the thread was being absorbed.

Nylon de pescar como sutura quirúrgica: una alternativa en los servicios de salud / Fishing nylon as surgical suture: a choice in health services

Con el fin de comprobar la eficacia y eficiencia del nylon de pescar como sutura qurúrgica, estudiamos prospectivamente 254 pacientes en quienes se utilizó dicho material para el cierre de la pared abdominal, entre Setiembre de 1992 a Junio 1994 en el Hospital de Florencia de Mora del IPSS, Gerencia La Libertad. Los porcentajes de infección de herida encontrados fueron de 1.2 por ciento para heridas limpias y 1.2 por ciento para heridas contaminadas, cifras concordantes con la literatura consultada. En un seguimiento promedio de un año, encontramos que 5 pacientes (1.9 por ciento), prestaron "rechazo" al material, identificándose en 2 de ellos técnica quirúrgica deficiente; y 7 por ciento tuvieron algún grado de defecto estético (queloides, hiperpigmentadas). No hubieron evisceraciones ni, eventraciones. Constatamos una importante reducción de costos respecto al uso de suturas tradicionales de hasta 2000 por ciento. Por lo antes expuesto, planteamos el uso del nylon de pescar como sutura quirúrgica como una alternativa recomendable.

Vida de prateleira de carne mecanicamente separada de frango estocada sob refrigeraçäo / Shelf-life of mechanically separated poultry meat (MSPM) stored under refrigeration

Carne mecanicamente separada (CMS) de dorsos de frango foi submetida a 3 tratamentos: I) acondicionada em sacos de poletileno; II) tratada com BHA/BHT (0,01 por cento) e nitrito de sódio e embalada em sacos de polietileno e III) acondicionadas em sacos de poliamida/polietileno a vácuo. Nos 3 tratamentos, os mateirais foram estocados em câmara mantida à temperatura de 0 a 2oC. Como controle, a carne foi embalada em sacos de poliamida/alumínio/polipropileno a vácuo e estocada a -20oC. A vida-de-prateleira da CMS estocada sob refrigeraçäo foi avaliada por critérios microbiológicos, químicos e sensoriais. Para todos os tratamentos, as contagens de psicotróficos, proteolíticos e mesófilos, inicialmente na faixa de 10(4) - 10(5) UFC/g. atingiram valores acima de 10(6) entre 5 e 7 dias. Até o quinto dia, as amostras embaladas a vácuo apresentaram menores contagens, abaixo de 10(6), mas ao final de 10 dias de estocagem, as amostras tratadas com BHA/BHT e nitrito apresentaram menores contagens, abaixo de 10(8). As avaliaçöes sensoriais de cor e odor indicaram que até o sétimo dia de estocagem somente as amostras do tratamento I apresentaram odor estranho, mas após 10 dias de estocagem somente as amostras do tratamento II apresentavam-se satisfatórias. Os teores de hipoxantina e de malonaldeído (TBA) näo mostraram boa correlaçäo com as determinaçöes microbiológicas, ao contrário dos teores de BVT que estiveram altamente correlacionados com as contagens microbiológicas. Esses resultados indicaram que a vida de prateleira de CMS de dorso de frango, embalada em sacos de polietileno e estocada entre 0 a 2oC, seira de 3 a 5 dias. Este tempo poderia ser estendido por pelo menos 2 dias com a adiçäo de BHA/BHT e nitrito ou pelo uso de embalagens a vácuo

Astigmatismo induzido pela cirurgia da catarata: sutura de nylon x poliéter / Surgically induced astigmatism after cataract extraction: nylon x poliester sutures

Foram analisados dois grupos de 20 pacientes com a finalidade de ser observada a evoluçäo e a magnitude do astigmatismo induzido no pós-operatório da cirurgia da catarata suturada com fios de nylon ou poliéster. Tal comparaçäo demonstrou que o astigmatismo induzido nos grupos nylon ou poliéster näo diferiu estatisticamente durante o período estudado. O grupo nylon mostrou um decréscimo do astigmatismo induzido significantemente maior que o grupo poliéster no período entre 90 e 180 dias. Os fios estudados parecem induzir astigmatismos com evoluçöes distintas no pós-operatório