Lymphaticovenous anastomosis in rabbits: A novel live experimental animal model for supermicrosurgical training.

BACKGROUND: Lymphaticovenous anastomosis is widely used in lymphedema management. Although its effectiveness in reducing edema in patients can be clinically observed, evaluating the long-term outcomes of this technique can be complex. This study established an animal model to assess the outcomes of lymphaticovenous anastomosis technique at 15 and 30-days post-surgery using indocyanine green lymphography, Patent Blue V dye injection, and histopathological examination. METHODS: An experimental model was established in the hindlimbs of 10 rabbits using the popliteal vein and afferent lymphatic vessels in the popliteal area. The subjects were divided into two groups: the first group (n = 5) underwent patency assessment at 0 and 15 days, and the second group (n = 5) at 0 and 30-days, resulting in 20 anastomoses. Patency was verified at 0, 15, and 30-days using indocyanine green lymphography and Patent Blue V injection. Histopathological examinations were performed on the collected anastomosis samples. RESULTS: The patency rate was 90% (19/20) initially, 60% (6/10) at 15 days post-surgery, and 80% (8/10) at 30-days. The average diameter of lymphatic vessels and veins was 1.0 mm and 0.8 mm, respectively. The median number of collateral veins was 3; the median surgical time was 65.8 min. Histopathology revealed minimal endothelial damage and inflammatory responses due to the surgical sutures, with vascular inflammation and thrombosis in a single case. Local vascular neoformations were observed. CONCLUSION: This study highlights the reliability and reproducibility of using rabbits as experimental models for training in lymphaticovenous anastomosis technique owing to the accessibility of the surgical site and dimensions of their popliteal vasculature.

Analysis of Extreme Maternal Morbidity at the Women´s Hospital of Aguascalientes.

Background Extreme maternal morbidity is defined as "events that potentially threaten the life of a pregnant woman during pregnancy, childbirth or the puerperium, but that due to a medical intervention the patient does not die", and this is an indicator of health quality at the hospital and demographic level. Objective The aim of this study was to determine the prevalence of extreme maternal morbidity in the Women´s Hospital of Aguascalientes, Mexico. Material and methods A retrospective cross-sectional study was conducted under the criteria of the World Health Organization and the Latin American Federation of Obstetrics and Gynecology Societies for the definition of extreme maternal morbidity to determine the prevalence of near miss morbidity, between January 1 and December 31, 2016. Results We found 165 cases of extreme maternal morbidity; no maternal death was registered during the study year. The extreme maternal morbidity rate was 0.016 and 16.69 per 1000 live births; the ratio of extreme maternal morbidity cases / obstetric admissions was 11.07. The prevalence of extreme maternal morbidity was 1.6%. The main causes of extreme maternal morbidity were hypertensive disorders (57%), obstetric hemorrhage (29%), sepsis (1%) and other (13%). Conclusion Extreme maternal morbidity in our institution had a similar prevalence to that reported in other countries and was mainly caused by hypertensive disorders.

Waste Refinery: The Valorization of Waste Plastics and End-of-Life Tires in Refinery Units. A Review.

This review collects a wide range of initiatives and results that expose the potential of the refineries to be converted into waste refineries. Thus, they will use their current units for the valorization of consumer society wastes (waste plastics and end-of-life tires in particular) that are manufactured with petroleum derivatives. The capacity, technological development, and versatility of fluid catalytic cracking (FCC) and hydroprocessing units make them appropriate for achieving this goal. Polyolefinic plastics (polyethylene and polypropylene), the waxes obtained in their fast pyrolysis, and the tire pyrolysis oils can be cofed together with the current streams of the industrial units. Conventional refineries have the opportunity of operating as waste refineries cofeeding these alternative feeds and tailoring the properties of the fuels and raw materials produced to be adapted to commercial requirements within the oil economy frame. This strategy will contribute in a centralized and rational way to the recycling of the consumer society wastes on a large scale. Furthermore, the use of already existing and, especially, depreciated units for the production of fuels and raw materials (such as light olefins and aromatics) promotes the economy of the recycling process.

Fuel production by cracking of polyolefins pyrolysis waxes under fluid catalytic cracking (FCC) operating conditions.

The catalytic cracking of high-density polyethylene pyrolysis waxes under fluidized catalytic cracking conditions has been investigated with the aim of producing fuels at large-scale from waxes obtained in pyrolysis plants located nearby collection and segregation points. Additionally, preliminary information about the capacity of these units to valorize waste polyolefins has been obtained. The catalytic cracking runs have been performed in a riser simulator reactor under industrial conditions: 500-560 °C; catalyst to oil mass ratio, 3, 5 and 7 gcat goil-1; and, contact time, 6 s. The product distribution has been quantified determining the yields of different fractions, which have been defined according to their boiling point range: dry gas, liquefied petroleum gas, naphtha, light cycle oil, heavy cycle oil and coke. The concentration of the families of compounds has been also determined, which are n-paraffins, iso-paraffins, olefins, naphthenes and aromatics. For the shake of comparison, the results of catalytic cracking of a common stream fed to the industrial units, i.e., vacuum gasoil, have been included. Globally, promising results have been obtained in the valorization of waste polyolefins by means of this combination of pyrolysis-cracking stages that expose, at the same time, the capacity of this unit to manage waste plastics.

Osteocalcin Serum Levels in Gestational Diabetes Mellitus and Their Intrinsic and Extrinsic Determinants: Systematic Review and Meta-Analysis.

BACKGROUND: Undercarboxylated osteocalcin (ucOC) increases insulin release and insulin resistance in mice. In humans, evidence is scarce but a correlation of ucOC and total osteocalcin (tOC) with glycemic status markers has been demonstrated. The relationship of ucOC and tOC with gestational diabetes mellitus (GDM) has been even less characterized. OBJECTIVE: To assess the mean difference of tOC and ucOC serum concentrations among nondiabetic pregnant women and women diagnosed as GDM in the second trimester of pregnancy and to determine the possible intrinsic and extrinsic contributors to this difference. METHODS: A systematic search was performed to identify relevant studies published in English and Spanish using PubMed, SCOPUS, ISI Web of Knowledge, and PROSPERO database for meta-analysis. Observational studies measuring mean serum levels of osteocalcin among GDM, with at least 10 subjects analyzed in each group were selected. Mean difference (MD) by random effects model was used. Heterogeneity between studies was assessed using Cochran's Q, H, and I 2 statistics. RESULTS: From 38 selected studies, 5 were retained for analysis for a total of 1119 pregnant women. Serum concentrations of tOC were not significantly different among women with GDM and nondiabetic pregnant controls (MD: 1.56; 95% CI: -0.70 to 3.82; p = 0.175). Meanwhile, ucOC serum levels were significantly higher among women with GDM (MD: 1.17; 95% CI: 0.24 to 2.11; p = 0.013). The only factor influencing tOC was the UV index, showing a reduction in mean difference between GDM and controls when exposed to higher concentrations of UV rays. CONCLUSIONS: This meta-analysis provides evidence to support the use of ucOC as a potential marker for GDM rather than tOC, yielding very little variability among studies and no difference among methods or brands used for its analysis.