Tumor de células gigantes esternal: esternectomía total y reconstrucción con barras de titanio más malla de polipropileno / Sternal Giant Cell Tumor: Total Sternectomy and Reconstruction with Titanium Rods Plus Polypropylene Mesh

El tumor de células gigantes (TCG) constituye un tumor óseo benigno relativamente frecuente. Se caracteriza por ser localmente agresivo y el lugar de presentación más frecuente es a nivel del esqueleto axial (fémur distal o tibia proximal). Hasta la actualidad, existen escasos informes de presentaciones atípicas, como a nivel del esternón. En este informe, se presenta el caso de una paciente mujer de 24 años que presenta tumoración indurada a nivel de la región esternal de crecimiento progresivo asociado a dolor. Los hallazgos radiológicos revelan tumoración osteolítica que tiene como origen el cuerpo del esternón y lo compromete casi en su totalidad. Este se proyecta hacia las partes blandas y llega al plano superficial. Debido a la extensión de la enfermedad y al compromiso extenso en el cuerpo del esternón, se realiza la resección del cuerpo y manubrio esternal. El defecto es reconstruido con malla de polipropileno, barras de titanio, parche de epiplón y autoinjerto de piel; se obtiene una adecuada estabilidad de la caja torácica y resultados estéticos favorables. El caso tiene un adecuado manejo oncológico puesto que la resección es completa con márgenes microscópicos libres (resección R0).

Giant cell tumor (GCT) constitutes a relatively common benign bone tumor, characteri-zed by its local aggressiveness. The most frequent site of occurrence is in the axial ske-leton (distal femur or proximal tibia). To date, there have been few reports of atypical presentations, such as at the level of the sternum. In this report, we present the case of a 24-year-old female patient who presented with an indurated mass in the sternal region, progressively growing and associated with pain. Radiological findings revealed an osteolytic mass originating from the body of the sternum, involving almost its entire extent and projecting into the soft tissues, reaching the superficial plane. Due to the extent of the disease and the extensive involvement of the sternal body, resection of the body and manubrium of the sternum was performed. The surgical defect was reconstructed with polypropylene mesh, titanium bars, an omental patch and a skin graft, achieving adequate stability of the thoracic cage and favorable cosmetic results.

Experiencia de la histeropexia vaginal, usando prótesis de polipropileno / Experience of vaginal hysteropexy, using polypropylene prosthesis

Introducción: El prolapso de órganos pélvicos (POP) o distopia genital, es el descenso o desplazamiento de los órganos del suelo pélvico a través del canal vaginal o fuera de este. Objetivo: Evaluar los resultados de la histeropexia vaginal en la corrección quirúrgica del prolapso genital apical grado III o IV, usando prótesis de polipropileno; además describir la tasa de éxito, recurrencias y complicaciones. Método: Estudio de cohorte, en 42 mujeres sometidas a histeropexia vaginal (histero-cistopexia ortotópica) mediante prótesis de polipropileno (Splentis®), entre 2016 y 2021. Se realizaron tres evaluaciones postoperatorias (tres, seis y 12 meses). Se hizo muestreo no probabilístico. Se utilizó estadística descriptiva. Resultados: La edad media fue de 56,19 ± 9,27 años. El tiempo quirúrgico de 58,95 ± 13,74 minutos, el sangrado quirúrgico de 119,85 ± 68,73 ml. La tasa de éxito a los 12 meses fue del 90,47%. La recurrencia del prolapso apical fue del 4,76% a los seis meses y del 9,52% a los 12 meses; el de compartimento anterior a los seis meses arrojó un 7,14%, frente al 11,9% a los 12 meses. El 14,28% de las pacientes presentaron complicaciones menores. La incidencia de incontinencia urinaria de esfuerzo a los 12 meses fue del 16,66%. Conclusiones: la histeropexia vaginal es un procedimiento efectivo y seguro, con bajas tasas de recurrencias o complicaciones. Es importante que se sigan haciendo estudios con mejores diseños estadísticos.

Introduction: Pelvic organ prolapse (POP), or genital dystopia, is the descent or displacement of pelvic floor organs through the vaginal canal or outside of it. Objective: To evaluate the results of vaginal hysteropexy in the surgical correction of grade III or IV apical genital prolapse, using polypropylene prosthesis; also describe the success rate, recurrences and complications. Method: Cohort study in 42 women undergoing vaginal hysteropexy (orthotopic hystero-cystopexy) using a polypropylene prosthesis (Splentis®); between 2016 and 2021. Three postoperative evaluations were carried out (three, six and twelve months). Non-probabilistic sampling was done. Descriptive statistics were used. Results: The mean age was 56.19 ± 9.27 years. Surgical time of 58.95 ± 13.74 minutes, surgical bleeding of 119.85 ± 68.73 ml. The success rate after twelve months was 90.47%. Apical prolapse recurrence was 4.76% at six months and 9.52% at twelve months; that of the previous compartment, after six months it showed 7.14%, compared to 11.9% after twelve months; 14.28% of the patients presented minor complications. The incidence of stress urinary incontinence, at twelve months, was 16.66%. Conclusions: Vaginal hysteropexy is an effective and safe procedure, with low rates of recurrence or complications. It is important that studies continue to be carried out with better statistical designs.

Quiste meniscal posterior a la sutura meniscal con monofilamento de polipropileno / Meniscal cyst after polypropylene monofilament suture

Introducción: la función del tejido meniscal es fundamental en la transmisión y distribución de cargas de la rodilla. En casos de lesión meniscal, la sutura es el tratamiento quirúrgico de elección, y pueden utilizarse diferentes materiales para realizarla. El objetivo del trabajo es analizar la aparición de quistes meniscales sintomáticos con el uso de sutura no reabsorbible del tipo monofilamento de polipropileno en un grupo de pacientes con lesiones en asa de balde y evaluar el material de sutura como causal de quiste.Materiales y métodos: se realizó un estudio retrospectivo de un grupo de pacientes con lesiones en asa de balde suturadas con material no reabsorbible del tipo monofilamento de polipropileno (MP) y sutura de alta resistencia de polietileno de ultra alto peso molecular UHMWPE (SAR) y se analizó la presencia de quiste meniscal sintomático como complicación. Los criterios de inclusión para este estudio fueron pacientes con lesiones en asa de balde a los cuales se les realizó sutura meniscal con técnicas combinadas con material de tipo no reabsorbible. Se excluyeron pacientes con lesiones que no fueran con patrón en asa de balde o a los cuales se les hizo sutura meniscal todo-adentro únicamente.Resultados: un total de veinticinco pacientes, quince de sexo masculino y diez de sexo femenino. La edad media del grupo evaluado fue de 27.8 años. El 72% fue suturado con sutura de alta resistencia (SAR) mientras que a un 28% se les realizó sutura con monofilamento de polipropileno (MP). El 92% de las lesiones se presentaron en el menisco interno. Se observaron tres pacientes con quistes meniscales sintomáticos asociados a la sutura MP, los cuales fueron tratados quirúrgicamente con buena evolución. Conclusión: identificamos en nuestra serie que la aparición de quistes sintomáticos se relaciona estrechamente con el uso de monofilamento de polipropileno (MP). Consideramos la utilización de hilos no reabsorbibles de alta resistencia (polietileno de ultra alto peso molecular UHMWPE) como la primera opción para realizar las suturas meniscales por la baja tasa de complicación y los buenos resultados. Nivel de Evidencia: IV

Introduction: The function of the meniscal tissue is fundamental in the transmission and distribution of knee loads. In cases of meniscal injury, suturing is the surgical treatment of choice, and different materials can be used to perform it. The aim of the work is to analyze the appearance of symptomatic meniscal cysts with the use of non-absorbable polypropylene monofilament suture in a group of patients with bucket handle injuries and to evaluate the suture material as a cause of the cyst. Materials and methods: a retrospective study was carried out on a group of patients with bucket-handle injuries sutured with non-absorbable polypropylene monofilament (MP) material and high-strength ultra-high molecular weight UHMWPE polyethylene (SAR) suture and the presence of a symptomatic meniscal cyst as a complication was analyzed. The inclusion criteria for this study were patients with bucket-handle injuries in whom meniscal suture was performed with combined techniques with non-resorbable material. Patients with injuries other than a bucket-handle pattern or who underwent all-in meniscal suturing only were excluded.Results: a total of twenty-five patients, fifteen males and ten females. The average age of the evaluated group was 27.8 years. 72% were sutured with high resistance suture (SAR) while 28% were sutured with polypropylene monofilament (MP). 92% of the injuries occurred in the medial meniscus. Three patients were observed with symptomatic meniscal cysts associated with the MP suture, which were treated surgically with good outcomes. Conclusion: we identified in our series that the appearance of symptomatic cysts is closely related to the use of polypropylene monofilament (MP). We consider the use of high-strength non-absorbable threads (ultra-high molecular weight polyethylene UHMWPE) as the first option to perform meniscal sutures due to the low complication rate and good results. Level of Evidence: IV

Neo-osteogenesis using an intentionally exposed polypropylene membrane after tooth extraction versus guided bone regeneration technique: a single-blind randomized controlled trial / Neo-osteogénesis utilizando una membrana de polipropileno expuesta intencionalmente después de la extracción del diente versus técnica de regeneración ósea guiada: ensayo clínico aleatorizado ciego / Neo-osteogênese utilizando uma membrana de polipropileno exposta intencionalmente após extração dentária versus técnica de regeneração óssea guiada: ensaio clínico randomizado e cego

Introduction: The intentionally exposed polypropylene (PP) membrane has been proposed for guided bone regeneration (GBR) of the alveo lar bone after extraction; however, there are biological limitations to this proposal. This study aimed to describe the effects of the PP membrane on neo-osteogenesis after tooth extraction, comparing to intentionally ex posed and primary soft tissue coverage techniques. Methodology: This clinical trial followed the TIDieR checklist and guide. Clinical and histo logical parameters of alveolar repair were compared between groups: 1 (control group), without regenerative procedure; 2, GBR; and 3, inten tionally exposed membrane. Results: Group 3 showed slight effect on the quality of new bone, compared to the control group. Although the GBR was underestimated by the early exposure of the membrane, alveo lar repair and newly formed bone were superior to the other groups. Poly propylene membrane intentionally exposed compromised the volume density of the immature and mineralized bone matrix, the osteoblast and osteocyte count, and stimulated the granulation tissue formation and local inflammatory infiltrate. Conclusions: Despite the exposure of the PP membrane in GBR, this technique improved the quality of new bone and alveolar repair compared to the surgical technique of intentional exposure and alveolus only sutured.

RESUMEN Introducción: La membrana de polipropileno (PP) intencionalmente expuesta ha sido propuesta para la regeneración ósea guiada (GBR) del hueso alveolar después de la extracción; sin embargo, existen limitaciones biológicas a esta propuesta. Este estudio tuvo como objetivo describir los efectos de la membrana de PP en la neo-osteogénesis después de la extracción del diente, en comparación con las técnicas de cobertura de tejido blando primarias y expuestas intencionalmente. Metodología: Este ensayo clínico siguió la lista de verificación y la guía TIDieR. Se compararon los parámetros clínicos e histológicos de la reparación alveolar entre los grupos: 1 (grupo control), sin procedimiento regenerativo; 2, GBR; y 3, membrana expuesta intencionalmente. Resultados: el grupo 3 mostró un ligero efecto sobre la calidad del hueso nuevo, en comparación con el grupo de control. Aunque la GBR fue subestimada por la exposición temprana de la membrana, la reparación alveolar y el hueso neoformado fueron superiores a los otros grupos. La membrana de polipropileno expuesta intencionalmente comprometió la densidad de volumen de la matriz ósea inmadura y mineralizada, el recuento de osteoblastos y osteocitos, y estimuló la formación de tejido de granulación y el infiltrado inflamatorio local. Conclusiones: A pesar de la exposición de la membrana de PP en GBR, esta técnica mejoró la calidad del hueso nuevo y la reparación alveolar en comparación con la técnica quirúrgica de exposición intencional y alvéolo solo suturado.

Introdução: A membrana de polipropileno (PP) intencionalmente exposta tem sido proposta para regeneração óssea guiada (ROG) do osso alveolar após exodontia; no entanto, existem limitações biológicas a esta proposta. Este estudo teve como objetivo descrever os efeitos da membrana de PP na neo-osteogênese após a extração dentária, comparando com as técnicas de exposição intencional e cobertura primária de tecidos moles. Metodologia: Este ensaio clínico seguiu a lista de verificação e o guia TIDieR. Parâmetros clínicos e histológicos do reparo alveolar foram comparados entre os grupos: 1 (grupo controle), sem procedimento regenerativo; 2, GBR; e 3, membrana intencionalmente exposta. Resultados: O Grupo 3 apresentou leve efeito na qualidade do novo osso, em comparação com o grupo controle. Embora o GBR tenha sido subestimado pela exposição precoce da membrana, o reparo alveolar e o osso neoformado foram superiores aos outros grupos. A exposição intencional da membrana de polipropileno comprometeu a densidade volumétrica da matriz óssea imatura e mineralizada, a contagem de osteoblastos e osteócitos e estimulou a formação de tecido de granulação e infiltrado inflamatório local. Conclusões: Apesar da exposição da membrana PP na ROG, esta técnica melhorou a qualidade do novo osso e da reparação alveolar em comparação com a técnica cirúrgica de exposição intencional e alvéolo apenas suturado.

The influence of the retention feature in artificial teeth on its attachment to the thermoplastic resin denture base / Influência da forma de retenção em dentes artificiais de resina acrílica na fixação na base de prótese termoplástica

Objective: Teeth play a crucial role in masticatory efficiency and esthetic harmony making rehabilitation of partially edentulous patients a challenge because of the limitations of conventional removable partial dentures. As a therapeutic alternative, thermoplastic polymers are used in current dental practice either for practical processing purposes or aesthetics. However, it is recognized that the bond between acrylic resin artificial teeth and thermoplastic polymers has no chemical interaction, and depends on retentive features added to the teeth. This study analyzed the efficacy of two retentive forms of features through compressive strength test and as a secondary outcome, fracture and displacement resistance test. Material and Methods: Three groups of samples each with 14 sets of acrylic teeth were compared when two retentive features, single hole and groove retention, and a control group with teeth without any specific form. The experimental unit consisted of six maxillary anterior teeth, positioned in a linear pattern into a polypropylene block, where each tooth was submitted to a static load until its removal, on a universal testing machine. Results: Those specimens with a groove retention presented larger resistance to displacement when compared to the other groups (p <0.05). This was emphasized by the fracture of the tooth tested, with part of the cervical portion remaining embed in the base, and not its displacement as with (or without) the retentive feature. Conclusion: In this study, the type of retention influenced significantly to a better retention considering teeth and thermoplastic polymer base. The data in this study indicates that a groove placed on the artificial tooth offers significantly better retention efficacy to the point where the displacement was only possible after its fracture (AU)

Objetivo: Os dentes são um fator essencial na eficiência mastigatória. A harmonia estética e a reabilitação dos indivíduos parcialmente dentados tornam-se um desafio, frente às limitações das próteses parciais removíveis convencionais. Como uma alternativa terapêutica, os polímeros termoplásticos são utilizados na odontologia contemporânea, tanto para o seu processamento prático como seu apelo estético. Entretanto, pouco se sabe a respeito da união entre a resina acrílica de dentes artificiais e resinas termoplásticas, assim como a influência dos mecanismos de retenção, uma vez que não há interação química entre eles. O objetivo deste estudo foi analisar duas formas de retenção de dentes de resina acrílica a bases de prótese de material termoplástico, por força compressiva e como desfecho secundário, teste de resistência a fratura e deslocamento dos dentes artificiais. Material e Métodos: O presente estudo analisou dois tipos diferentes de retenções: uma cavidade com único ponto e uma canaleta de mesial a distal; e como grupo controle, dentes colocados sem qualquer recurso específico. A unidade experimental consistiu de seis dentes superiores anteriores, posicionados em linha em um bloco de polipropileno. Em cada dente artificial foi aplicada força até a sua remoção, em uma máquina universal de ensaios. Resultados: Os resultados mostraram que a retenção com canaleta apresentou maior força de deslocamento, quando comparado com os outros grupos (p <0,05). Tal fato foi evidenciado pelo teste de fratura e deslocamento, no qual parte da porção cervical do dente artificial permaneceu unida à base, não ocorrendo o deslocamento com (ou sem) a retenção. Conclusão: Neste estudo, o tipo de retenção influenciou de forma significante a retenção de dentes artificiais de resina acrílica a bases de prótese termoplásticas. Os dados deste estudo indicam que a confecção da retenção em canaleta nos dentes artificiais oferece significante aumento na eficiência da retenção, ao ponto em que o deslocamento do dente ocorreu somente após sua fratura (AU).

Estabilização zigomática e retalho de avanço facial lateral em canino filhote / Zygomatic stabilization and lateral facial advancement flap in a puppy dog

O trauma é frequentemente relatado na rotina clínica de pequenos animais, podendo gerar fraturas de componentes ósseos e lesões de tecidos moles adjacentes. No presente trabalho, objetivou-se relatar o caso de um canino, macho, sem raça definida, de sete meses de idade, vítima de trauma craniomaxilofacial decorrente de mordedura, diagnosticado com fratura e deslocamento de osso zigomático, além de importante laceração de pele. O tratamento estabelecido baseou-se no debridamento da ferida, estabilização cirúrgica de arco zigomático com fios de Nylon e na sutura dos ferimentos de pele causados. Em um segundo tempo cirúrgico, foi realizada enucleação e recobrimento do defeito na órbita com malha cirúrgica de polipropileno, além de remoção de tecido exuberante e confecção de retalho subdérmico de avanço facial lateral para recobrimento do defeito cutâneo. A complicação evidenciada na primeira intervenção cirúrgica foi a deiscência das suturas de pele, enquanto no segundo tempo cirúrgico, não houve sinais de complicações. No pós-operatório, o paciente apresentou evolução clínica satisfatória, recebendo alta médica 21 dias após o segundo procedimento cirúrgico realizado. Tendo em vista a adequada evolução clínica, bem como os reduzidos efeitos colaterais, sugere-se que a conduta clínica e técnicas cirúrgicas adotadas para tratamento do paciente em questão foram efetivas.

Trauma is frequently reported in the small animal clinics, and can lead to fractures of cranial bone components and injuries to the adjacent soft tissues. In the present study, the objective was to report the case of a seven-month-old male mongrel dog, that had a craniomaxillofacial trauma resulting from a bite, characterized by zygomatic bone fracture and displacement, in addition to a major skin laceration. The stablished treatment was based on wound debridement, surgical stabilization of the zygomatic arch with nylon threads and in the suturing of skin wounds. In a second surgical procedure, enucleation was performed and a surgical polypropylene mesh was applied to cover the orbital defect, exuberant tissue was removed and a subdermal advancement flap was used to cover the skin defect. The complication observed in the first surgical intervention was dehiscence of the skin sutures, while in the second surgical procedure, there were no signs of complications. Postoperatively, the patient had a satisfactory clinical recovery, being discharged 21 days after the second surgical procedure. Considering the adequate clinical evolution and the reduced complications, it issuggestedthat the clinical conduct and surgical techniques adopted for the treatment of the patient in question were effective.

Reconstrução de palato com malha de polipropileno e prótese acrílica para correção de fístula oronasal adquirida em cão / Palate reconstruction with polypropylene mesh and acrylic prosthesis in dog for correcton of acquired oronosal fistulae

As fístulas oronosais adquiridas são defeitos que permitem a comunicação anormal entre as cavidades oral e nasal. Inúmeras causas podem ser atribuídas à etiologia de tal defeito. O presente trabalho visa relatar o caso de um cão com fístula oronasal adquirida que foi submetido à reconstrução cirúrgica do palato com o uso de malha de polipropileno e prótese acrílica. Após estabilização do quadro clínico e remoção manual das larvas, o paciente foi encaminhado para o desbridamento cirúrgico das lesões orais e correção do defeito no palato. A palatoplastia foi realizada com o uso da malha e resina de polimetilmetacrilato autopolimerizável. A malha foi suturada sobre o defeito palatino com pontos simples separados e fio náilon 3-0 nas extremidades da ferida. Em seguida, a resina foi preparada e, ao atingir consistência adequada, foi aplicada e modelada sobre o a malha de polipropileno com o auxílio de um descolador de Molt, sendo também suturada nas bordas da fístula com pontos simples separados e fio náilon 3-0. No mesmo tempo cirúrgico foi inserida uma sonda esofágica para alimentação enteral. Devido complicações cirúrgicas no pós operatório, o paciente foi submetido a mais duas intervenções cirúrgicas para desfecho satisfatório do tratamento. Conclui-se que associação entre a tela de polipropileno e a prótese acrílica foi uma alternativa exequível para a palatoplastia em cão.

Acquired oronosal fistulae are abnormal communication between the oral and nasal cavities. A oronasal fistula can be the result of different causes, like oral myiasis. The objetctive of these paper is to report the case of a dog with acquired oronasal fistula that underwent surgical reconstruction of the palate using polypropylene mesh and acrylic prosthesis. After stabilization of the patient ́s clinical condition and mecanic removal of the larvae, the dog was referred for surgical debridement of the oral lesions and correction of the defect in the palate. Palatoplasty was performed using a mesh and polymethylmethacrylate resin. The mesh was sutured over the palatal defect with separate simple suture and 3-0 naylon thread at the ends of the wound. Then, the resin was prepared and, upon reaching adequate consistency, it was applied and shaped over the polypropylene mesh with Molt peeler. It was also sutured on the edges of the fistula with separate simple suture and 3-0 nylon suture. At the same surgical time, an esophageal tube was inserted for enteral feeding. Due to complications, the dog underwent two more surgical interventions for a satisfactory treatment outcome. It is concluded that the association between the polypropylene mesh and the acrylic prosthesis was a practical alternative for palatoplasty in dogs after oral myiasis.

An innovative technique of chest wall stabilization and reconstruction in traumatic flail chest: The figure-of-eight suture with polypropylene mesh and musculofascial flap / 中华创伤杂志(英文版)

Surgical stabilization of the flail chest is challenging and has no established guidelines. Chest wall integrity and stability are the main factors that ensure the protection of intrathoracic organs and an adequate respiratory function. Here, we report a novel chest wall reconstruction technique in a 45-year-old man with a traumatic left flail chest and open pneumothorax diagnosed both clinically and radiographically. Rib approximation and chest wall reconstruction was done using intercostal figure-of-eight suture and polypropylene mesh with vascularized musculofascial flap. The patient improved gradually and was discharged after three weeks of total hospital stay. He returned to regular working after a month with no evidence of respiratory distress or paradoxical chest movement. Follow-up visit at one year revealed no lung hernia or paradoxical chest movement. This is a novel, feasible and cost-effective modification of chest wall reconstruction that can be adopted for thoracic wall repair in case of open flail chest, which needs emergency surgical interventions even in resource constraint settings.

Can platelet-rich plasma coating improve polypropylene mesh integration? An immunohistochemical analysis in rabbits

ABSTRACT Purpose: Despite high success rates in the treatment of urinary incontinence, complications related to the use of polypropylene (PP) meshes are still a concern, especially in vaginal prolapses surgeries. The objective of this study was to assess the effect of autologous platelet-rich plasma (PRP) coating on the integration of PP meshes implanted in the vaginal submucosa of rabbits. Materials and Methods: Thirty adult New Zealand rabbits were randomly divided into two groups (n=15): PP, implanted with conventional PP meshes; and PRP, implanted with autologous PRP coated PP meshes. Animals in both groups (n=5) were euthanized at 7, 30 and 90 days postoperatively, the vaginas extracted and sent to immunohistochemical analysis for the assessment of the pro-inflammatory agent TNF-α, anti-inflammatory agents TGF-β and IL-13, collagen metabolism marker MMP-2, and angiogenesis marker CD-31. AxioVision™ image analysis was used for the calculation of the immunoreactive area and density. Statistical analysis was performed with ANOVA followed by Tukey test (p <0.05). Results: Animals in the PRP group showed significantly increased expression of the angiogenesis agent CD-31 at all experimental times when compared to the PP group (p <0.0001). However, no differences concerning the expression of the other markers were observed between the groups. Conclusion: The addition of autologous PRP gel to PP meshes can be simply and safely achieved and seems to have a positive effect on implantation site angiogenesis. Further investigations are required to ascertain PPR coated meshes clinical efficacy in prolapses and stress urinary incontinence surgeries.

Contaminación por microplásticos en playas del Pacífico de Guatemala: abundancia y características / Microplastics pollution in Pacific beaches of Guatemala: abundance and characteristics

La contaminación por microplásticos (MPs) de tamaño menor a 5 mm ha tomado relevancia en los últimos años debido a su impacto en los ecosistemas. En Guatemala, se carece de información relacionada con MPs, por lo que este estudio tuvo como objetivo evaluar la abundancia y características de MPs en cuatro playas del Pacífico de Guatemala, Ocós, Tulate, Sipacate y Las Lisas. Se colectaron muestras de arena en mayo y octubre de 2019. Los MPs se aislaron y se clasificaron por forma, y el tipo de polímero se identificó a través de un equipo de espectroscopia infrarroja con transformada de Fourier (ATR-FTIR). La abundancia expresada en MPs/m2 en mayo fue de 25.6, 5.6, 0.8 y 0 MPs/m2 para Tulate, Las Lisas, Ocós y Sipacate; mientras que en octubre fue de 59.6, 23.2, 17.6 y 17.6 MPs/m2 en Tulate, Ocós, Las Lisas y Sipacate. Fragmentos, foam, pellets y láminas fueron las formas predominantes de MPs que se encontraron en las playas. El análisis por ATR-FTIR muestra que los principales polímeros identificados en las playas son polietileno, poliestireno y polipropileno. Los resultados de este estudio indican que las playas del Pacífico de Guatemala están contaminadas por MPs de diferentes tipos de polímeros. Además, estos resultados ofrecen información importante a los responsables de la toma de decisiones sobre la eliminación y el manejo de la basura plástica marina.

Microplastics < 5 mm (MPs) pollution has gained relevance in the last years because of its impact on the ecosystems. In Guatemala, information related to MPS as an environmental stressor is lacking, that is why this study aimed to assess the abundance and characteristics of MPS in four beaches to the Pacific Ocean of Guatemala, Ocós, Tulate, Sipacate, and Las Lisas. Sand samples were collected in May and October 2019. MPs were isolated and classified by shape and the type of polymer was identified by using Attenuated Total Reflec-tion-Fourier Transform Infrared Spectroscopy (ATR-FTIR). The abundance expressed in MPs/m2 in May was 25.6, 5.6, 0.8 and 0 MPs/m2 in Tulate, Las Lisas, Ocós, and Sipacate; whereas in October was 59.6, 23.2, 17.6, and 17.6 M Ps /m2 in Tulate, Las Lisas, Ocós and Sipacate. Fragments, foam, pellets, and film were the predominant shapes found on the beaches. The ATR-FTIR analysis indicates that the main polymers identified in the beaches are polyethylene, polystyrene, and polypropylene. The results of this study indicate that the Pacific Beaches of Guatemala are contaminated by MPs of different types of polymers. These results offer important information to decision makers about disposal and management of marine plastic litter.

Analysis of tissue inflammatory response, fibroplasia, and foreign body reaction between the polyglactin suture of abdominal aponeurosis in rats and the intraperitoneal implant of polypropylene, polypropylene/polyglecaprone and polyester/porcine collagen meshes

ABSTRACT Purpose To compare tissue inflammatory response, foreign body reaction, fibroplasia, and proportion of type I/III collagen between closure of abdominal wall aponeurosis using polyglactin suture and intraperitoneal implant of polypropylene, polypropylene/polyglecaprone, and polyester/porcine collagen meshes to repair defects in the abdominal wall of rats. Methods Forty Wistar rats were placed in four groups, ten animals each, for the intraperitoneal implant of polypropylene, polypropylene/polyglecaprone, and polyester/porcine collagen meshes or suture with polyglactin (sham) after creation of defect in the abdominal wall. Twenty-one days later, histological analysis was performed after staining with hematoxylin-eosin and picrosirius red. Results The groups with meshes had a higher inflammation score (p < 0.05) and higher number of gigantocytes (p < 0.05) than the sham group, which had a better fibroplasia with a higher proportion of type I/III collagen than the tissue separating meshes (p < 0.05). There were no statistically significant differences between the three groups with meshes. Conclusions The intraperitoneal implant of polypropylene/polyglecaprone and polyester/porcine collagen meshes determined a more intense tissue inflammatory response with exuberant foreign body reaction, immature fibroplasia and low tissue proportion of type I/III collagen compared to suture with polyglactin of abdominal aponeurosis. However, there were no significant differences in relation to the polypropylene mesh group.

Levels of BPA in makdous, a traditional Syrian food, using solid-phase extraction followed by HPLC

Bisphenol A (BPA), an endocrine disrupter, can migrate from packaging material into food stuff. This research was designed to measure BPA levels in makdous, a traditional Syrian food. Forty three samples of makdous stored in different plastic containers (polyethylene (PE), polypropylene (PP), and unspecified plastic containers) were analyzed every 3 months for one year beginning July 2017. Quantification of BPA was carried out by an RP-HPLC system equipped with fluorescence detector after solid phase extraction. Migration was found in PE and PP plastic containers with slight differences. Statistically significant differences in BPA levels were observed between samples assayed after two weeks of preparation and samples assayed after 12 months (mean 16.32 vs. 38.26 µg/kg, p value=0.003). According to these amounts, BPA levels were all under the specific migration limit of 0.05 mg/kg as newly referred in Regulation (EU) No 2018/213. These levels of exposure would only contribute to 2.15% and 2.75% of the EFSA t-TDI in both men and women respectively based on mean dietary exposure estimates derived from a 24-h dietary information study from 875 participants. Hence there are no concerns about potential health risks from makdous consumption

Comparative analysis of tissular response after abdominal wall repair using polypropylene mesh and bovine pericardium mesh / Análise comparativa da resposta tecidual após reparo da parede abdominal utilizando tela de polipropileno e de pericárdio bovino

ABSTRACT Background: The use of polypropylene meshes for surgical repair of the abdominal wall contributes to a reduction of the of recurrence rates of hernias or defects. However, its intra-abdominal use comes along with the formation of adhesions and several complications. The study and the search for alternative materials, including bovine pericardium, have been regarded as an option for the correction and treatment of resulting hernias with better adaptations and effectiveness. Aim: Evaluating the inflammatory process of the bovine pericardium in comparison with the inflammatory process of synthetic polypropylene mesh. Method: Bovine pericardium mesh and polypropylene mesh were placed, both on the same animal. The first group had the mesh removed for analysis on day 20, and the second group on day 40. The variables congestion, granulation, giant cells, necrosis, acute inflammation, chronic inflammation and collagen were analyzed. Results: All variables were found in greater numbers as a response to the polypropylene mesh, except for the collagen, which, on day 40, was greater in response to the bovine pericardium mesh. Conclusion: The data in this study suggest that there is less inflammatory reaction in response to bovine pericardium mesh when compared to polypropylene mesh.

RESUMO Racional: O uso de telas de polipropileno para a correção cirúrgica da parede abdominal contribui para redução dos índices de recidiva das hérnias ou defeitos. No entanto, o seu uso intra-abdominal cursa com a formação de aderências e diversas complicações. O estudo e a busca por materiais alternativos, como pericárdio bovino, têm se mostrado uma opção na correção e tratamento de hérnias que resultem com melhores adaptações e efetividades. Objetivo: Avaliar o processo inflamatório do pericárdio bovino em comparação ao processo inflamatório da tela sintética de polipropileno. Método: Foi realizada a colocação de tela de pericárdio bovino e polipropileno, ambas no mesmo animal. O primeiro grupo as teve retiradas para análise no dia 20, e o segundo grupo no dia 40. Foram analisadas as variáveis congestão, granulação, células gigantes, necrose, inflamação aguda, inflamação crônica e colágeno. Resultados: Todas as variáveis foram encontradas em maior número como resposta a tela de polipropileno, exceto a variável colágeno, que no dia 40 apresentou-se em maior quantidade em resposta à tela de pericárdio bovino. Conclusão: Há menor reação inflamatória em resposta a tela de pericárdio bovino, quando comparada com a de polipropileno.

Between prolene®, ultrapro® and bard soft® meshes which presents the best performance in the repair of the abdominal wall? / Dentre as telas prolene®, ultrapro® ebard soft® qual apresenta melhor desempenho no reparo da parede abdominal?

ABSTRACT Background: In the definition of the mesh to be used to correct hernias, porosity, amount of absorbable material and polypropylene should be considered in the different stages of healing process. Aim: To evaluate the inflammatory reaction in the use of macro and microporous meshes of high and low weight in the repair of defects in the abdominal wall of rats. Methods: Ninety Wistar rats (Rattus norvegicus albinus) were used. The animals were submitted to similar surgical procedures, with lesion of the ventral abdominal wall, maintaining the integrity of the parietal peritoneum and correction using the studied meshes (Prolene®, Ultrapro® and Bard Soft®). Euthanasia was performed at 30, 60 and 120 days after surgery. The abdominal wall segments were submitted to histological analysis using H&E, Masson's trichrome, immunohistochemistry, picrosirius red and tensiometric evaluation. Results: On the 120th day, the tensiometric analysis was superior with Ultrapro® macroporous mesh. The inflammatory process score showed a significant prevalence of subacute process at the beginning and at the end of the study. Microporous meshes showed block encapsulation and in macroporous predominance of filamentous encapsulation. Conclusion: The Ultrapro® mesh showed better performance than the others in healing process of the abdominal wall.

RESUMO Racional: Na definição da tela a ser utilizada na correção das hérnias deve-se considerar a porosidade, quantidade de material absorvível e polipropileno ou inabsorvível nas diversas fases da cicatrização. Objetivo: Avaliar a reação inflamatória das telas macro e microporosas de alta e baixa gramatura no reparo de defeito da parede abdominal de ratos. Método: Foram utilizados 90 ratos da raça Wistar (Rattus norvegicus albinus). Os animais foram submetidos a procedimentos cirúrgicos semelhantes, com lesão da parede abdominal ventral, mantendo a integridade do peritônio parietal e correção utilizando as telas Prolene®, Ultrapro® e Bard Soft®. Realizou-se a eutanásia aos 30, 60 e 120 dias de pós-operatório. Os segmentos da parede abdominal foram submetidos à análise histológica com H&E, tricômio de Masson, imunoistoquímica, picrosirius red e análise tensiométrica. Resultado: No 120º dia a análise tensiométrica mostrou superioridade da tela macroporosa Ultrapro®. O escore do processo inflamatório demonstrou prevalência significativa de processo subagudo no início e no final do estudo. As telas microporosas mostraram encapsulamento em bloco e as macroporosas encapsulamento predominantemente filamentar. Conclusão: A tela Ultrapro® mostrou melhor desempenho em relação às demais na cicatrização da parede abdominal.

Associação de arcabouço de polipropileno e células tronco mesenqimais para uso em engenharia de tecido / Association of polypropylene scaffolds and mesenchymal stem cells for use in tissue engineering

A engenharia de tecidos tem como objetivo substituir tecidos danificados, manipulando células, confecção de arcabouços e a utilização de moléculas que estimulem o tecido. A proposta deste estudo foi avaliar duas técnicas de cultivo de células-tronco mesenquimais (MSC) em diferentes placas de cultura, utilizando dois tipos de telas de polipropileno (macroporoso e microporoso), para obter as melhores condições de interação entre a tela e as células, e definir uma proposta de protético para engenharia de tecidos. As telas de polipropileno foram cultivadas com células-tronco mesenquimais de tecido adiposo (ADSCs) isoladas de camundongos C57B1/6 GFP+ durante quinze dias em placas revestidas com metacrilato ou não revestidas com metacrilato. A quantidade de ADSCs aderidas foram verificadas diariamente em Câmara de Neubauer e através de uma curva de crescimento realizada pelo ensaio MTT. As ADSCs aderidas às malhas foram visualizadas com marcação de DAPI, panóticas, hematoxilina e eosina imuno-histoquímica e imunofluorescência. O melhor protocolo foi na tela microporosa, no o período de sete dias de cultivo e em placas sem metacrilato. Conclui-se que a tela de polipropileno fornece um bom suporte para as ADSCs se aderirem podendo ser utilizada na engenharia de tecidos.

Tissue engineering replaces injured tissues by manipulating cells, making scaffolds, and using molecules that stimulate the tissue. Mesenchymal stem cells (MSCs) are good candidates for tissue engineering, as this is one of the cell types which are recruited to repair injured tissues. Scaffolds are structural devices that allow cell fixation and migration, with polypropylene meshes being an example. This study aims to evaluate the culture of adipose tissue-derived mesenchymal stem cells (ADSCs), isolated from C57Bl/6 GFP + mice, in two types of polypropylene meshes (macroporous and microporous) in conventional culture plates and plates coated with methacrylate, over a period of fifteen days. The objective was to obtain the best interaction protocol between the mesh and the cells. The choice of the best method was based on adherence, maintenance of adherence and viability during culture. The amount of ADSCs adhering was checked daily by counting in a Neubauer Chamber and by using a growth curve performed with the MTT assay. The ADSCs adhering to the meshes were visualized with DAPI, panotic, hematoxylin and eosin, immunohistochemistry (integrin), and immunofluorescence (actin). ADSCs adhere to all forms of culture and to the two types of polypropylene mesh. ADSCs adhered more to the microporous mesh, within the seven day period of culture and in the plates without methacrylate. Thus, polypropylene meshes offer a good scaffold for ADSCs to adhere to.

Association of polypropylene scaffolds and mesenchymal stem cells for use in tissue engineering / Associação de arcabouço de polipropileno e células tronco mesenquimais para uso em engenharia de tecido

Tissue engineering replaces injured tissues by manipulating cells, making scaffolds, and using molecules that stimulate the tissue. Mesenchymal stem cells (MSCs) are good candidates for tissue engineering, as this is one of the cell types which are recruited to repair injured tissues. Scaffolds are structural devices that allow cell fixation and migration, with polypropylene meshes being an example. This study aims to evaluate the culture of adipose tissue-derived mesenchymal stem cells (ADSCs), isolated from C57Bl/6 GFP + mice, in two types of polypropylene meshes (macroporous and microporous) in conventional culture plates and plates coated with methacrylate, over a period of fifteen days. The objective was to obtain the best interaction protocol between the mesh and the cells. The choice of the best method was based on adherence, maintenance of adherence and viability during culture. The amount of ADSCs adhering was checked daily by counting in a Neubauer Chamber and by using a growth curve performed with the MTT assay. The ADSCs adhering to the meshes were visualized with DAPI, panotic, hematoxylin and eosin, immunohistochemistry (integrin), and immunofluorescence (actin). ADSCs adhere to all forms of culture and to the two types of polypropylene mesh. ADSCs adhered more to the microporous mesh, within the seven day period of culture and in the plates without methacrylate. Thus, polypropylene meshes offer a good scaffold for ADSCs to adhere to.

A engenharia de tecidos substitui tecidos danificados com a manipulação de células, confecção de arcabouços e a utilização de moléculas que estimulem o tecido. As células-tronco mesenquimais (MSCs) são boas candidatas para engenharia de tecido, pois são um dos tipos celulares recrutadas para a reparação de tecidos lesionados. O arcabouço deve ser um dispositivo estrutural que forneça uma estrutura para o crescimento e a diferenciação celular no sítio, sendo a tela de polipropileno um exemplo. O objetivo deste estudo foi avaliar o cultivo de células-tronco mesenquimais de tecido de adiposo (ADSCs), isoladas de camundongos C57Bl/6 GFP+, em dois tipos de telas de polipropileno (macroporosa e microporosa) em placas de cultura convencionais e revestidas com metacrilato, durante quinze dias, para obter o melhor protocolo de interação entre a tela e as células. A escolha do melhor método foi baseada na adesão, manutenção da adesão e viabilidade durante cultivo. A quantidade de ADSCs aderidas foi verificada diariamente em contagem em Câmara de Neubauer e através de uma curva de crescimento realizada através de ensaio de MTT. As ADSCs aderidas nas telas foram visualizadas com a marcação de DAPI, panótico, hematoxilina e eosina, imumo-histoquímica (integrina) e imunofluorescência (actina). Nas duas formas de cultivo e nos dois tipos de telas de polipropileno houve aderência das ADSCs. Houve maior aderência na tela microporosa, no período de sete dias de cultivo e em placas sem metacrilato. Conclui-se que a tela de polipropileno oferece um bom arcabouço para as ADSCs se aderirem.

Cold chain time- and temperature-controlled transport of vaccines: a simulated experimental study

Preparation and evaluation of schisandrin B-loaded F127 modified lipid-polymer nanoparticles for inhibition of breast cancer lung metastasis / 中国中药杂志

In the current study, schisandrin B(SchB)-loaded F127 modified lipid-polymer hybrid nanoparticles(SchB-F-LPNs) were developed to improve the inhibition of breast cancer lung metastasis. Modified nanoprecipitation method was used to prepare SchB-F-LPNs. The nanoparticles were spherical in shape with shell-core structure by TEM observation. SchB-F-LPNs showed a mean particle size of(234.60±6.11) nm with zeta potential of(-5.88±0.49) mV. XRD results indicated that SchB existed in the nanoparticles in an amorphous state. The apparent permeability coefficient through porcine mucus of F-LPNs was 1.43-fold of that of LPNs as shown in the in vitro mucus penetration study. The pharmacokinetics study showed that the C_(max) of SchB was(369.06±146.94) μg·L~(-1),(1 121.34±91.65) μg·L~(-1) and(2 951.91±360.53) μg·L~(-1) respectively in SchB suspensions group, SchB-LPNs group and SchB-F-LPNs group after oral administration in rats. With SchB suspensions as the reference formulation, the relative bioavailability of SchB-F-LPNs was 568.60%. SchB-F-LPNs inhibited the morphological change during transforming growth factor-β1(TGF-β1)-induced epithelial-mesenchymal transition. In addition, SchB-F-LPNs significantly decreased the number of metastatic pulmonary nodules in 4 T1 tumor-bearing mice, suggesting that SchB-F-LPNs may inhibit the metastasis of breast cancer. These results reveal the promising potential of SchB-F-LPNs in treatment of breast cancer lung metastasis.

Does a bilateral polypropylene mesh alter the duct deferens morphology, testicular size and testosterone levels? Experimental study in rats

Abstract Purpose To evaluate the effect of a PP mesh on duct deferens morphology, testicular size and testosterone levels. Methods Forty adult male rats were distributed into groups: 1) no surgery; 2) inguinotomy; 3) mesh placed on the duct deferens; and 4) mesh placed on the spermatic funiculus. After 90 postoperative days, the inguinal region was resected, and blood samples were collected for the measurement of serum testosterone (pg/dl). The ducts deferens were sectioned in three axial sections according to the relationship with the mesh — cranial, medial and caudal. The wall thickness and duct deferens lumen area were measured. Results The morphology of the duct deferens was preserved in all groups. The mesh placement did not alter this morphology in any of the analyzed segments. Surgery, with or without mesh placement, did not alter the morphology, wall thickness or lumen area (p>0.05). In all operated groups, serum testosterone levels were similar (p>0.05) but there was a decrease in testicle size (p<0.05). Conclusion Surgery, with or without mesh placement, did not alter the morphology of the duct deferens and, although this treatment resulted in testicular size reduction, it did not affect serum testosterone levels.

Biomechanical and adhesion comparison of linea alba prophylactic reinforcement with coated and uncoated three-dimensional T-shaped mesh in rabbits

Abstract Purpose: Incisional hernia (IH) is a frequent complication of median laparotomy. The use of prophylactic mesh to reduce IH incidence has gained increasing attention. We hypothesized that in an animal model, linea alba prophylactic reinforcement with a three-dimensional T-shaped polypropylene mesh results in greater abdominal wall resistance. Methods: Study was performed in 27 rabbits. After abdominal midline incision, animals were divided into three groups according to the laparotomy closure method used: (1)3D T-shaped coated mesh; (2)3D T-shaped uncoated mesh; and (3) closure without mesh. After 4 months, each animal's abdominal wall was resected and tensiometric tests were applied. Results included IH occurrence, adhesions to the mesh, and wound complications. Results: There was no significant difference between the groups in maximum tensile strength (p=0.250) or abdominal wall elongation under maximum stress (p=0.839). One rabbit from the control group developed IH (p=1.00). Small intestine and colon adhesions occurred only in the uncoated mesh group (p<0.001) and the degree of adhesions was higher in this group compared to the coated mesh group (p<0.05). Conclusion: Use of the current 3D T-shaped prophylactic mesh model did not result in a significant difference in tensiometric measurements when compared with simple abdominal wall closure in rabbits.