In Vitro Antimycotic Activity and Structural Damage against Canine Malassezia pachydermatis Strains Caused by Mexican Stingless Bee Propolis.

This work describes the antimycotic activity of propolis from the stingless bees Scaptotrigona mexicana and Tetragonisca angustula, collected from two Mexican regions (Veracruz and Chiapas, respectively), against three clinical isolates and the reference strain ATCC 14522 of Malassezia pachydermatis, the causative agent of canine otitis. The chemical components of the ethanolic extracts of propolis were determined by gas chromatography coupled with mass spectrometry (GC-MS), and sesquiterpenes were the predominant compounds. The antimycotic activity was evaluated by plate microdilution. The induced changes in the yeasts were evaluated by fluorescence microscopy and staining with calcofluor white and propidium iodide. The minimum inhibitory concentration (MIC) was 7.11 mg/mL, and the minimum fungicidal concentration was 21.33 mg/mL for both extracts. The EPPs of Scaptotrigona mexicana and Tetragonisca angustula caused substantial damage to yeast morphology, where the propidium iodide staining of the yeasts treated with both EEPs revealed the penetration of this marker, which indicates the destruction of the cell wall and plasma membrane of the fungi. This result suggests that these types of propolis could be used as alternative treatments for canine external otitis. To the best of our knowledge, this seems to be the first scientific report that has demonstrated structural damage in Malassezia pachydermatis by Mexican stingless bee propolis.

Mesenchymal Stem Cell Therapy for Treating the Underlying Causes of Diabetes Mellitus and Its Consequences.

Diabetes mellitus (DM) is a multifaceted pathological condition, which at present is being considered an epidemic disease keeping the rampant rate of its increase in almost all population groups of the world in consideration. Out of the two types of DM described, T1D is characterized as an autoimmune condition that leads to the destruction of pancreatic ß-cells by macrophages and T-cells, thereby, adversely affecting the production of insulin. On the other hand, T2D, often caused by insulin resistance, is commonly related to unhealthy habits, and therefore, it can be prevented in most cases. In both of the conditions, high levels of proinflammatory cytokines like IL-6, TNF-α, and INF-Æ´, lead to chronic inflammation, and elevated oxidative stress resulting in apoptosis and destruction of tissues. Although several treatments are available to treat the symptoms, the underlying causes are not well addressed. One of the most promising approaches to tackle the ill effects and the primary causes of DM is mesenchymal stem cell (MSC) therapy. The use of MSC therapy, because of the immunomodulatory and regenerative properties recorded in this type of cells in a number of experiments carried out in animal models and clinical trials of the disease, has reported positive outcomes. This review covers the principal mechanisms of action induced during MSC therapy in reference to the described pathophysiological pathways of both T1D and T2D. In addition, how this therapeutic intervention can counteract the ill effects of this condition leading to the promotion of tissue regeneration has been covered.

Stem Cells Therapy as a Possible Therapeutic Option in Treating COVID-19 Patients.

An unfortunate emergence of a new virus SARS-CoV-2, causing a disease known as COVID-19, has spread all around the globe and has caused a pandemic. It primarily affects the respiratory tract and lungs in some cases causing severe organ damage and pneumonia due to overwhelming immune responses. Clinical reports show that the most commons symptoms are fever, dry cough, and shortness of breath, along with several other symptoms. It is thought that an immense cytokine dysregulation in COVID-19 patients is caused following the virus infection. Notably, if patients present with pre-existing specific comorbidities like diabetes or high blood pressure, rates of COVID-19 induced complications and deaths are escalated. Mesenchymal stem cell (MSC) therapy has been shown to alleviate pneumonia and acute respiratory syndrome (ARDS) symptoms, through their immunomodulatory activities in COVID-19 patients. Although more research studies and clinical trial results are needed to elucidate the exact mechanism by which MSCs provide relief to COVID-19 infected patients. Results from clinical trials are encouraging as patients treated with MSCs, regain lung functions and have restored levels of cytokines and trophic factors underscoring the fact that stem cell therapy can be, at least, a complementary therapy to alleviate sufferings in COVID-19 patients. This review discusses the possible therapeutic uses of MSCs for treating COVID-19. Graphical Abstract.

Stem Cell Therapy Offers a Possible Safe and Promising Alternative Approach for Treating Vitiligo: A Review.

BACKGROUND: Normal skin pigmentation pattern is an extremely important component of the appearance of a person, as it can be a significant factor in the social context of any person. A condition known as vitiligo is caused by the death of melanocytes leading to pigmentation loss in the skin. This affects all races across the globe and sometimes leads to social avoidance as in some communities, it is stigmatized. Although there are different pathobiological processes suspected because of the different underlying causes of vitiligo, autoimmunity and oxidative stress are suspected to be the most probable ones. OBJECTIVE: In this review, we present an overview of the underlying mechanisms causing and developing the disease. Also, some of the most successful treatments along with the clinical applications of Mesenchymal Stem Cells (MSCs) as a comprehensive approach for treating this condition will be covered. RESULTS: Autoreactive CD8+ T-cells are the primary suspect considered to be responsible for the destruction of melanocytes. Therefore, topical use of autoimmune inhibitors including those derived from MSCs, thanks to their immune-modulatory properties, have been reported to be successful in the promotion of repigmentation. MSCs can suppress the proliferation of CD8+T via the NKG2D pathway while inducing T-cell apoptosis. The use of pharmacological agents for reducing cellular oxidative stress with the help of topical application of antioxidants and growth factors also have been in use. Intravenous administration of MSCs has been shown to regulate the level of reactive oxidative species (ROS) in a mice model. Growth factors derived from platelet-rich-plasma (PRP) or from MSCs caused rapid tissue regeneration. CONCLUSIONS: Finally, MSC therapy also has been shown to stimulate the mobilization of healthy melanocytes, leading to successful repigmentation of skin lesions in vitiligo patients.

Presence and diversity of Salmonella isolated from layer farms in central Ecuador.

Background: Given the considerable role played by Salmonella in the incidence of food poisoning around the world, surveillance of this infection is prioritized by both food producers and health care authorities. Data remains insufficient concerning the prevalence of Salmonella in poultry systems in Ecuador and in Latin America in general. Methods: In this study we evaluated the prevalence and diversity of Salmonella serovars in samples taken from 21 layer farms and backyard layers in central Ecuador during August-November 2017.   Salmonella was isolated following standardized methods (ISO 6579) and the serovar determination was carried out by PCR. Results: A significant presence of Salmonella was detected, with an incidence of 76% (95% confidence interval (CI): 58-94) in farms, 33% (95%CI: 13-53) in pooled cloacal swabs from layer hens, 33% (95%CI: 12-55) on feed samples, and 10% (95%CI: 0-22) in backyard layer feces from traditional local markets. The dominant serovars detected were S. Infantis and S. Typhimurium. Conclusions: This study forms a basis for further surveillance of Salmonella serovars in layer farms in central Ecuador.