Tissue reaction after subcutaneous implants of a new material composed of ethylene-vinyl acetate and starch for future use as a biomaterial.

This study aimed to evaluate the tissue reaction of ethylene-vinyl acetate (EVA) in 4 different compositions and processing: EVA foamed at high pressure with ultrasound (EVACU); EVA with 15% starch foamed at high pressure with ultrasound (EVAMCU); EVA with 15% starch foamed at high pressure without ultrasound and EVA foamed at high pressure without ultrasound as future use as a porous scaffold. Scanning electron microscopy images showed the influence of starch, reducing the diameter of pores. The number of open pores was also reduced with the addition of starch. The ultrasound applied during the manufacturing of composites does not affect these characteristics. Eighteen rats were used to test the tissue reaction of materials and PTFE (polytetrafluoroethylene), proven biocompatible material. After 7, 15, and 60 days of surgery, the materials were removed and processed for microscopic evaluation and counting of the inflammatory infiltrate. The data shows inflammatory reaction similar to PTFE. However, in the quantitative analysis at 60 days, the EVACU and EVAMCU showed less quantity of mononuclear cells (p < 0.05). Thus, the results suggest that the use of ultrasound in the production method (EVA) seems to have improved cell behavior regarding the reduction of infiltration over the period, with tissue response equivalent to the PTFE. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 107B: 400-407, 2019.

Glucose homeostasis in rats treated with 4-vinylcyclohexene diepoxide is not worsened by dexamethasone treatment.

4-vinilcyclohexene diepoxide (4-VCD) causes premature ovarian failure and may result in estrogen deficiency, characterizing the transition to estropause in rodents (equivalent to menopause in women). Estropause/menopause is associated with metabolic derangements such as glucose intolerance and insulin resistance. Glucocorticoids (GCs) are known to exert diabetogenic effects. Thus, we aimed to investigate whether rats with premature ovarian failure are more prone to the diabetogenic effects of GC. For this, immature female rats received daily injections of 4-VCD [160mg/kg body weight (b.w.), intraperitoneally (i.p.)] for 15 consecutive days, whereas control rats received vehicle. After 168days of the completion of 4-VCD administration, rats were divided into 4 groups: CTL-received daily injections of saline (1mL/kg, b.w., i.p.) for 5days; DEX-received daily injections of dexamethasone (1mg/kg, b.w., i.p.) for 5days; VCD-treated as CTL group; VCD+DEX-treated as DEX group. Experiments and euthanasia occurred one day after the last dexamethasone injection. 4-VCD-treated rats exhibited ovary hypotrophy and reduced number of preantral follicles (p<0.05). Premature ovarian failure had no impact on the body weight gain or food intake, but both were reduced by the effects of dexamethasone. The increase in blood glucose, plasma insulin and triacylglycerol levels as well as the reduction in insulin sensitivity caused by dexamethasone treatment was not exacerbated in the VCD+DEX group of rats. Premature ovarian failure did change neither the hepatic content of glycogen and triacylglycerol nor the glycerol release from perigonadal adipose tissue. Glucose intolerance was observed in the VCD group after an ipGTT (p<0.05), but not after an oral glucose challenge. Glucose intolerance and compensatory pancreatic ß-cell mass caused by GC were not modified by ovarian failure in the VCD+DEX group. We conclude that reduced ovarian function has no major implications on the diabetogenic effects promoted by GC treatment, indicating that other factors related to aging may make rats more vulnerable to GC side effects on glucose metabolism.

Caracterización del ambiente físico en viviendas Petrocasas en el Asentamiento Simón Bolívar de Cienfuegos (2008-2009) / Characterization of the physical environment in petrohouses from the village of Simón Bolívar in the province of Cienfuegos (2008-2009)

En varios asentamientos del país se han construido viviendas Petrocasas de policloruro de vinilo, relleno con hormigón sobre balsa y cubierta de lámina de aluminio revestida de papel asfalto por ambas caras. El policloruro de vinilo como material de construcción resulta controversial en relación a sus efectos en la salud. Con el objetivo de caracterizar desde el punto de vista sanitario el ambiente físico en viviendas Petrocasas de Cienfuegos, fue conducido un estudio descriptivo en dos semanas seleccionadas de las estaciones seca y húmeda de 2008 y 2009. Se monitoreó factores de riesgo físico en una muestra de 6 viviendas seleccionadas según la opinión de expertos, del total de las 104 viviendas del asentamiento según su ubicación en las filas de viviendas: centro, culata de fila y fachada. Se estudió el ruido, componente magnético del campo electromagnético de baja frecuencia, iluminación natural, artificial, microclima y penetración del viento. La evaluación del monitoreo se efectuó por descriptores estadísticos, modelos de regresión, varianza y espectro de potencia bivariado con los paquetes estadísticos: SPSS v. 17,0 y Statistica v. 8,0. Durante la estación seca, la temperatura del aire es mayor en la habitación principal de viviendas con fachada al sur. En ambas estaciones, las temperaturas y humedades relativas de las viviendas son más altas que en la intemperie. Las cubiertas y paredes muestran calentamientos ante el asoleamiento. Los coeficientes de iluminación natural presentan elevadas reflexiones. Los valores del campo electromagnético son bajos. En la estación seca los niveles sonoros reflejan una contaminación acústica moderada. Concluimos que el microclima en el interior de las viviendas durante el día es inconfortable(AU)

Petrohouses have been built in several villages in the country. These houses are made of polyvinyl chloride, filled with raft concrete and covered with aluminum sheets coated with asphalt paper on both sides. The health effects of polyvinyl chloride as a construction material is a matter of controversy. With the purpose of carrying out a health characterization of the physical environment in Cienfuegos petrohouses, a descriptive study was conducted during two weeks selected from the dry and wet seasons of 2008 and 2009. Physical risk factors were monitored in a sample of 6 houses selected on the basis of expert opinion, of the total 104 houses in the village, according to their location in the rows: front, mid and end positions. The variables studied were noise, magnetic component of the low frequency electromagnetic field, natural and artificial lighting, microclimate and wind penetration. Monitoring was evaluated with statistical descriptors, regression models, variance and bivariate power spectrum, with the statistical software SPSS v. 17.0 and Statistica v. 8.0. In the dry season, air temperature is higher in the main room of houses with facades facing the south. In both seasons, temperature and relative humidity values are higher inside the houses than outside. Covers and walls heat up when hit by the sun. Natural lighting coefficients show high reflection values. Electromagnetic field values are low. In the dry season, sound levels show moderate acoustic contamination. It is concluded that the microclimate inside houses during the day is uncomfortable(AU)

Subcutaneous tissue reaction and cytotoxicity of polyvinylidene fluoride and polyvinylidene fluoride-trifluoroethylene blends associated with natural polymers.

Cytotoxicity and subcutaneous tissue reaction of innovative blends composed by polyvinylidene fluoride and polyvinylidene fluoride-trifluoroethylene associated with natural polymers (natural rubber and native starch) forming membranes were evaluated, aiming its applications associated with bone regeneration. Cytotoxicity was evaluated in mouse fibroblasts culture cells (NIH3T3) using trypan blue staining. Tissue response was in vivo evaluated by subcutaneous implantation of materials in rats, taking into account the presence of necrosis and connective tissue capsule around implanted materials after 7, 14, 21, 28, 35, 60, and 100 days of surgery. The pattern of inflammation was evaluated by histomorphometry of the inflammatory cells. Chemical and morphological changes of implanted materials after 60 and 100 days were evaluated by Fourier transform infrared (FTIR) absorption spectroscopy and scanning electron microscopy (SEM) images. Cytotoxicity tests indicated a good tolerance of the cells to the biomaterial. The in vivo tissue response of all studied materials showed normal inflammatory pattern, characterized by a reduction of polymorphonuclear leukocytes and an increase in mononuclear leukocytes over the time (p < 0.05 Kruskal-Wallis). On day 60, microscopic analysis showed regression of the chronic inflammatory process around all materials. FTIR showed no changes in chemical composition of materials due to implantation, whereas SEM demonstrated the delivery of starch in the medium. Therefore, the results of the tests performed in vitro and in vivo show that the innovative blends can further be used as biomaterials.

Clinical profile of Implanon: a single-rod etonogestrel contraceptive implant.

This 3-year study investigating the contraceptive efficacy and tolerability of Implanon in 635 volunteers demonstrates that it was well tolerated and had excellent, reversible, contraceptive efficacy. No pregnancies (Pearl index, 0; 95% CI 0.0-0.2) occurred during 1,200 woman-years of exposure. Irregular bleeding, mainly frequent and prolonged, was the primary reason for discontinuation (19.0%). Infrequent bleeding (29-51%) was the most common bleeding disturbance. Adverse events, other than bleeding irregularities, were generally mild to moderate in intensity and resulted in 9.3% of discontinuations. Over 85% of women with dysmenorrhea at baseline noted an improvement at the end of treatment, while 4% reported new or worsened symptoms. The most commonly reported non-bleeding adverse events were breast pain (16%), acne (12.6%), vaginitis (12%) and pharyngitis (10.5%). However, acne present at enrolment improved or disappeared during treatment in 59% of women. Less than 5% of women experienced implant site symptoms after insertion or removal, mainly mild pain of short duration. Average insertion and removal times were 2.2 and 5.4 min, respectively. In most women, menses returned to normal within 3 months of implant removal. Of those using no contraceptive method, 13.8% became pregnant within 90 days. Implanon represents a highly effective contraceptive option for women.

A multicentre efficacy and safety study of the single contraceptive implant Implanon. Implanon Study Group.

An open, multicentre study was performed to assess efficacy, safety and acceptability of the single-rod contraceptive implant Implanon. The study involved 635 young healthy women, who were sexually active and of childbearing potential. The women were followed up every 3 months over the entire study period. Originally the study was designed for 2 years, but was extended to 3 years in a group of 147 women from two centres. Altogether, 21 centres in nine different countries participated. The average age of the women was 29 years (range 18-42 years), of whom 83.5% had been pregnant in the past. No pregnancy occurred during treatment with Implanon, resulting in a Pearl Index of 0 (95% confidence interval: 0.0-0.2). In the first 2 years, 31% had discontinued the treatment. Of the 147 women in the study extension, nine discontinued (6%) treatment. Bleeding irregularities was the main reason for discontinuation during the first 2 years of use (17.2%) and adverse experiences in the third year (3.4%). Implant insertion and removal were fast and uncomplicated in the vast majority (97%) of cases. Return of fertility was prompt. In conclusion, Implanon has excellent contraceptive action during its lifetime of 3 years. The safety profile is acceptable and not essentially different from progestogens in general.

Exposure to vinyl chloride and angiosarcoma of the liver: a report of the register of cases.

The Association of Plastic Manufacturers in Europe maintains a register of all cases of angiosarcoma of the liver (ASL) resulting from exposure to vinyl chloride monomer (VCM). This register has recorded all known VCM related cases of the disease worldwide that have been histologically confirmed. Although likely to be incomplete, it is the most comprehensive tabulation of such cases available and, by the end of 1984, 118 men had been registered. The information from analysis of the cases currently on the register is used to make an approximate projection of the number of cases to be expected in the future. The conclusion from this projection is that the industry is reaching the halfway stage in the appearance of VCM related ASL.