digital-planimetry-for-assessing-wound-closure-kinetics-mouse

Digital Planimetry for Assessing Wound Closure Kinetics in a Mouse Model

Chronic wounds, due to their high prevalence, are a serious global health concern. Effective therapeutic strategies can significantly accelerate healing, ...

Autonomous University of the State of Mexico

In the physiological state a multitude of gut hormones are released into the circulation at the same time depending on the quality and quantity of the diet. These hormones interact with receptors at various points in the "gut-brain axis" to affect short-term and intermediate-term feelings of hunger and satiety. The combined effects of macronutrients on the predominant gut hormone secretion are still poorly understood. Besides, adipokines form an important part of an "adipoinsular axis" dysregulation which may contribute to β -cell failure and hence to type 2 diabetes mellitus (T2DM). Even more, gestational diabetes mellitus (GDM) and T2DM seem to share a genetic basis. In susceptible individuals, chronic exaggerated stimulation of the proximal gut with fat and carbohydrates may induce overproduction of an unknown factor that causes impairment of incretin production and/or action, leading to insufficient or untimely production of insulin, so that glucose intolerance develops. The bypass of the duodenum and jejunum might avoid a putative hormone overproduction in the proximal foregut in diabetic patients that might counteract the action of insulin, while the early presentation of undigested or incompletely digested food to the ileum may anticipate the production of hormones such as GLP1, further improving insulin action.

Peripheral Pathways in the Food-Intake Control towards the Adipose-Intestinal Missing Link.

Pesticides are often used in agriculture, especially in floriculture. They are frequently applied in binary or ternary mixtures. Nevertheless, their impact on the genetic material has been scarcely explored. In this study, the mutagenic and cytostatic effect of three widely used pesticides, alone and combined, were analyzed. Briefly, lymphocytes cultures were obtained from peripheral blood samples of five healthy donors to determine the sister chromatid exchange and the replicative index (RI). Then, lymphocytes were exposed to Tamaron (100 ppm), Lannate (200 ppm) and Manzate (300 ppm) alone and combined. For the binary mixtures, the concentrations used were 50 ppm of Tamaron, 100 ppm of Lannate and 150 ppm of Manzate. For the ternary mixtures the following concentrations were used: Tamaron (33 ppm), Lannate (70 ppm) and Manzate (100 ppm). Finally, differential staining was performed. It was found that the frequency of SCE/cell showed a significant difference (P ≤ 0.05) between the control (2.66) and the individual treatments of Tamaron (4.87), Lannate: (5.12) and Manzate (4.23). Also, the values of the SCE in the binary mixture of Tamaron+Lannate (5.57), Tamaron+Manzate (6.06) and Lannate+Manzate (6.22) and the ternary mixture (6.63) were statistically different compared to the control. In the RI there was a significant difference between the control (1.98) and the Manzate (1.87). RI differences were also statistically significant (P ≤ 0.05) in mixtures of Tamaron+Lannate (1.64), Tamaron+Manzate (1.63), Lannate+Manzate (1.69) and total mixture (1.53). Therefore, it is suggested that these pesticides alone and in mixtures have both mutagenic and cytostatic synergistic effect in human lymphocytes in vitro.

In vitro evaluation of the mutagenic and cytostatic effect of Tamaron, Lannate and Manzate alone and in mixture.

Hydrogels are suitable materials to promote cell proliferation and tissue support because of their hydrophilic nature, porous structure and sticky properties. However, hydrogel synthesis involves the addition of additives that can increase the risk of inducing cytotoxicity. Sterilization is a critical process for hydrogel clinical use as a proper scaffold for tissue engineering. In this study, poly(ethylene glycol) (PEG), poly(ethylene glycol)-chitosan (PEG-CH) and multi-arm PEG hydrogels were synthesized by free radical polymerization and sterilized by gamma irradiation or disinfected using 70 % ethanol. The biocompatibility assessment in human fibroblasts and hemocompatibility studies (hemolysis, platelet aggregation, morphology of mononuclear cells and viability) in peripheral blood from healthy volunteers (ex vivo), were performed. The sterilization or disinfection effect on hydrogel structures was evaluated by FT-IR spectroscopy. Results indicated that hydrogels do not induce any damage to fibroblasts, erythrocytes, platelets or mononuclear cells. Moreover, there was no significant difference in the biocompatibility after the sterilization or disinfection treatment. However, after gamma irradiation, several IR spectroscopic bands were shifted to higher or lower energies with different intensity in all hydrogels. In particular, several bands associated to carboxyl or hydroxyl groups were slightly shifted, possibly associated to scission reactions. The disinfection treatment (70 % ethanol) and γ-irradiation at 13.83 ± 0.7 kGy did not induce morphological damages and yielded sterile and biocompatible PEG hydrogels potentially useful for clinical applications.

Hydrogels based on poly(ethylene glycol) as scaffolds for tissue engineering application: biocompatibility assessment and effect of the sterilization process.

The development of breast cancer is influenced by the adipose tissue through the proteins leptin and adiponectin. However, there is little research concerning AdipoR1 and AdipoR2 receptors and the influence of leptin over them. The objective of this work was to analyze the expression of AdipoR1 and AdipoR2, modulated by differential concentrations of leptin in an obesity model (10 ng/mL, 100 ng/mL, and 1000 ng/mL) associated with breast cancer in MCF-7 and HCC1937 cell lines. Each cell line was characterized through immunohistochemistry, and the expression of AdipoR1 and AdipoR2 was analyzed by PCR in real time using TaqMan® probes. Leptin induced an increase in cell population of MCF-7 (23.8%, 10 ng/mL, 48 h) and HCC1937 (17.24%, 1000 ng/mL, 72 h). In MCF-7, the expression of AdipoR1 decreased (3.81%, 1000 ng/mL) and the expression of AdipoR2 increased by 13.74 times (10 ng/mL) with regard to the control. In HCC1937, the expression of AdipoR1 decreased by 86.28% (10 ng/mL), as well as the expression of AdipoR2 (50.3%, 100 ng/mL). In regard to the results obtained, it could be concluded that leptin has an effect over the expression of AdipoR1 and AdipoR2 mRNA.

Expression of AdipoR1 and AdipoR2 Receptors as Leptin-Breast Cancer Regulation Mechanisms.

Proteins are key biomolecules for most biological processes, their function is related to their conformation that is also dictated by their sequence of amino acids. Through evolution, nature has produced an immense variety of enzymatic tools of high efficiency and selectivity, and thanks to the understanding of the molecular basis of life and the technological advances, scientists have learned to introduce mutations and select mutant enzymes, to optimize and control their molecular fitness characteristics mainly for industrial, medical and environmental applications. The relationship between protein structure and enzymatic functionality is essential, and there are various experimental and instrumental techniques for unravelling the molecular changes, activities and specificities. Protein engineering applies computational tools, in hand with experimental tools for mutations, like directed evolution and rational design, along with screening methods to obtain protein variations with the desired properties under a short time frame. With innovations in technology, it is possible to fine tune properties in proteins and reach new frontiers in their applications. The present review will briefly discuss these points and methods, with a glimpse on their strengths and pitfalls, while giving an overview of the versatility of synthetic proteins and their huge potential for biotechnological and biomedical fields.

Tailoring Proteins to Re-Evolve Nature: A Short Review.

Understanding the spatial and temporal patterns of mortality rates in a highly heterogeneous metropolis, is a matter of public policy interest. In this context, there is no, to the best of our knowledge, previous studies that correlate both spatio-temporal and age-specific mortality rates in Mexico City. Spatio-temporal Kriging modeling was used over five age-specific mortality rates (from the years 2000 to 2016 in Mexico City), to gain both spatial (borough and neighborhood) and temporal (year and trimester) data level description. Mortality age-specific patterns have been modeled using multilevel modeling for longitudinal data. Posterior tests were carried out to compare mortality averages between geo-spatial locations. Mortality correlation extends in all study groups for as long as 12 years and as far as 13.27 km. The highest mortality rate takes place in the Cuauhtémoc borough, the commercial, touristic and cultural core downtown of Mexico City. On the contrary, Tlalpan borough is the one with the lowest mortality rates in all the study groups. Post-productive mortality is the first age-specific cause of death, followed by infant, productive, pre-school and scholar groups. The combinations of spatio-temporal Kriging estimation and time-evolution linear mixed-effect models, allowed us to unveil relevant time and location trends that may be useful for public policy planning in Mexico City.

Metropolitan age-specific mortality trends at borough and neighborhood level: The case of Mexico City.

This work shows the synthesis of a polyvinylpyrrolidone (PVP) hydrogel by heat-activated polymerization and explores the production of hydrogels with an open porous network by lyophilisation to allow the three-dimensional culture of human oral mucosa stem cells (hOMSCs). The swollen hydrogel showed a storage modulus similar to oral mucosa and elastic solid rheological behaviour without sol transition. A comprehensive characterization of porosity by scanning electron microscopy, mercury intrusion porosimetry and nano-computed tomography (with spatial resolution below 1 μm) showed that lyophilisation resulted in the heterogeneous incorporation of closed oval-like pores in the hydrogel with broad size distribution (5 to 180 μm, d = 65 μm). Human oral mucosa biopsies were used to isolate hOMSCs, expressing typical markers of mesenchymal stem cells in more than 95% of the cell population. Direct contact cytotoxicity assay demonstrated that PVP hydrogel have no negative effect on cell metabolic activity, allowing the culture of hOMSCs with normal fusiform morphology. Pore connectivity should be improved in future to allow cell growth in the bulk of the PVP hydrogel.

Lyophilized Polyvinylpyrrolidone Hydrogel for Culture of Human Oral Mucosa Stem Cells.

Assessment of the air quality in metropolitan areas is a major challenge in environmental sciences. Issues related include the distribution of monitoring stations, their spatial range, or missing information. In Mexico City, stations have been located spanning the entire Metropolitan zone for pollutants, such as CO, NO, O, SO, PM, PM, NO, NO  , and PM  . A fundamental question is whether the number and location of such stations are adequate to optimally cover the city. By analyzing spatio-temporal correlations for pollutant measurements, we evaluated the distribution and performance of monitoring stations in Mexico City from 2009 to 2018. Based on our analysis, air quality evaluation of those contaminants is adequate to cover the 16 boroughs of Mexico City, with the exception of SO, since its spatial range is shorter than the one needed to cover the whole surface of the city. We observed that NO and NO  concentrations must be taken into account since their long-range dispersion may have relevant consequences for public health. With this approach, we may be able to propose policy based on systematic criteria to locate new monitoring stations.

Article	Year
Peripheral Pathways in the Food-Intake Control towards the Adipose-Intestinal Missing Link. International journal of endocrinology\| PubMed ID: 24381591	2013
In vitro evaluation of the mutagenic and cytostatic effect of Tamaron, Lannate and Manzate alone and in mixture. Journal of environmental science and health. Part. B, Pesticides, food contaminants, and agricultural wastes\| PubMed ID: 27385630	2016
Hydrogels based on poly(ethylene glycol) as scaffolds for tissue engineering application: biocompatibility assessment and effect of the sterilization process. Journal of materials science. Materials in medicine\| PubMed ID: 27752974	2016
Expression of AdipoR1 and AdipoR2 Receptors as Leptin-Breast Cancer Regulation Mechanisms. Disease markers\| PubMed ID: 29311755	2017
Tailoring Proteins to Re-Evolve Nature: A Short Review. Molecular biotechnology\| PubMed ID: 30264233	2018
Metropolitan age-specific mortality trends at borough and neighborhood level: The case of Mexico City. PloS one\| PubMed ID: 33465102	2021
Lyophilized Polyvinylpyrrolidone Hydrogel for Culture of Human Oral Mucosa Stem Cells. Materials (Basel, Switzerland)\| PubMed ID: 33466418	2021
Spatio-Temporal Representativeness of Air Quality Monitoring Stations in Mexico City: Implications for Public Health. Frontiers in public health\| PubMed ID: 33585375	2020

Miriam V. Flores-Merino

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