Light-activated conjugated polymer nanoparticles to defeat pathogens associated with bovine mastitis.

Bovine mastitis (BM) represents a significant challenge in the dairy industry. Limitations of conventional treatments have prompted the exploration of alternative approaches, such as photodynamic inactivation (PDI). In this study, we developed a PDI protocol to eliminate BM-associated pathogens using porphyrin-doped conjugated polymer nanoparticles (CPN).

1,25 dihydroxyvitamin D-mediated effects on bovine innate immunity and on biofilm-forming Staphylococcus spp. isolated from cattle with mastitis.

Mastitis is one the most widespread and serious diseases in dairy cattle. Recurrent and chronic infections are often attributable to certain pathogenicity mechanisms in mastitis-causing pathogens such as Staphylococcus spp. These include growing in biofilm and invading cells, both of which make it possible to resist or evade antimicrobial therapies and the host's immune system.

Teat-apex colonizer Bacillus from healthy cows antagonizes mastitis-causing Staphylococcus aureus biofilms.

Staphylococcus aureus is the most frequent causal agent of bovine mastitis, which is largely responsible for milk production losses worldwide. The pathogen's ability to form stable biofilms facilitates intramammary colonization and may explain disease persistence. This virulence factor is also highly influential in the development of chronic intramammary infections refractory to antimicrobial therapy, which is why novel therapies that can tackle multiple targets are necessary.

Chitosan can improve antimicrobial treatment independently of bacterial lifestyle, biofilm biomass intensity and antibiotic resistance pattern in non-aureus staphylococci (NAS) isolated from bovine clinical mastitis.

Bovine mastitis is the most frequent and costly disease that affects dairy cattle. Non-aureus staphylococci (NAS) are currently one of the main pathogens associated with difficult-to-treat intramammary infections. Biofilm is an important virulence factor that can protect bacteria against antimicrobial treatment and prevent their recognition by the host's immune system.

A comparative study of antimicrobial activity of differently-synthesized chitosan nanoparticles against bovine mastitis pathogens.

The greatest concern in dairy farming nowadays is bovine mastitis (BM), which results mainly from bacterial colonization of the mammary gland. Antibiotics are the most widely used strategy for its prevention and treatment, but overuse has led to growing antimicrobial resistance. Pathogens have also developed other mechanisms to persist in the udder, such as biofilm formation and internalization into bovine epithelial cells.

Interaction between bovine mammary epithelial cells and planktonic or biofilm Staphylococcus aureus: The bacterial lifestyle determines its internalization ability and the pathogen recognition.

The main cause of mastitis, one of the most costly diseases in the dairy industry, is bacterial intramammary infection. Many of these bacteria are biofilm formers. Biofilms have been associated with resistance to antibiotics and to the host immune system.

Physicochemical, in vitro antioxidant and cytotoxic properties of water-soluble chitosan-lactose derivatives.

In this study, water-soluble chitosan (Ch) derivatives were synthesized by the Maillard reaction between Ch and lactose. The Ch derivatives were characterized by FT-IR, H-NMR and SLS to determine their structure, degree of deacetylation (DD), and molecular weight (Mw). The solubility at physiological pH, the in vitro antioxidant activity against hydroxyl radical, anion superoxide radical and ABTS cation radical, and the cytotoxicity against epithelial cells of the rat ileum (IEC-18) were also evaluated.

Chitosan nanoparticles enhance the antibacterial activity of the native polymer against bovine mastitis pathogens.

Staphylococcus is the most commonly isolated genus from animals with intramammary infections, and mastitis is the most prevalent disease that affects dairy cows in many countries. These pathogens can live in biofilms, a self-produced matrix, which allow them evade the innate immune system and the antibiotic therapy, thereby producing persistent infections. The aim of this study was to explore the antimicrobial potential of chitosan nanoparticles (Ch-NPs) obtained by the reverse micellar method.

Chitosan disrupts biofilm formation and promotes biofilm eradication in Staphylococcus species isolated from bovine mastitis.

Staphylococci are the main pathogens associated with hard-to-control intramammary infections in dairy cattle, and bacterial biofilms are suspected to be responsible for the antimicrobial resistance and persistence of this disease. Biofilms have the ability to resist to higher levels of antibiotics and reduce their efficacy. It is thus necessary to develop strategies targeted to bacterial biofilm infections.

Soy genistein administered in soluble chitosan microcapsules maintains antioxidant activity and limits intestinal inflammation.

We used water-soluble Chitosan obtained by Maillard reaction with glucosamine to microencapsulate soy genistein (Ge) and preserve its biological activity for oral administration. Release of Ge was pH dependent with a super Case II mechanism at pH 1.2 and an anomalous transport with non-Fickian kinetics at pH 6.

Chitosan and cloxacillin combination improve antibiotic efficacy against different lifestyle of coagulase-negative Staphylococcus isolates from chronic bovine mastitis.

Bovine mastitis affects the health of dairy cows and the profitability of herds worldwide. Coagulase-negative staphylococci (CNS) are the most frequently isolated pathogens in bovine intramammary infection. Based on the wide range of antimicrobial, mucoadhesive and immunostimulant properties demonstrated by chitosan, we have evaluated therapy efficiency of chitosan incorporation to cloxacillin antibiotic as well as its effect against different bacterial lifestyles of seven CNS isolates from chronic intramammary infections.

Commensal coagulase-negative Staphylococcus from the udder of healthy cows inhibits biofilm formation of mastitis-related pathogens.

Bovine mastitis, considered the most important cause of economic losses in the dairy industry, is a major concern in veterinary medicine. Staphylococcus aureus and coagulase-negative staphylococci (CNS) are the main pathogens associated with intramammary infections, and bacterial biofilms are suspected to be responsible for the persistence of this disease. CNS from the udder are not necessarily associated with intramammary infections.

Combined calcitriol and menadione reduces experimental murine triple negative breast tumor.

Background: Calcitriol (D) or 1,25(OH)D inhibits the growth of several tumor cells including breast cancer cells, by activating cell death pathways. Menadione (MEN), a glutathione-depleting compound, may be used to potentiate the antiproliferative actions of D on cancer cells. We have previously shown in vitro that MEN improved D-induced growth arrest on breast cancer cell lines, inducing oxidative stress and DNA damage via ROS generation.

Oxidative stress, cell cycle arrest and differentiation contribute toward the antiproliferative action of BSO and calcitriol on Caco-2 cells.

The prognosis and incidence of colon cancer are linked to vitamin D3 serum levels. To evaluate the effects of D,L-buthionine-S,R-sulfoximine (BSO), 1,25(OH)2D3 and their combination on intestinal Caco-2 cell growth, to elucidate the possible cellular mechanisms involved in their antiproliferative action, and to determine whether BSO acts as a sensitizer to 1,25(OH)2D3 treatment, enabling minimization of the toxic effects caused by high doses of the steroid. Human colon cancer Caco-2 cells were treated with 1,25(OH)2D3, BSO, both, or vehicle.

Molecular aspects of vitamin D anticancer activity.

Environment may influence the development and prevention of cancer. Calcitriol has been associated with calcium homeostasis regulation. Many epidemiological, biochemical, and genetic studies have shown non-classic effects of vitamin D, such as its involvement in the progression of different cancers.

Buthionine sulfoximine and 1,25-dihydroxyvitamin D induce apoptosis in breast cancer cells via induction of reactive oxygen species.

Calcitriol or 1,25(OH)(2)D(3) is a negative growth regulator of breast cancer cells. The aim of this study was to determine whether L-buthionine-S,R-sulfoximine, a glutathione-depleting drug, modifies the antiproliferative effects of 1,25(OH)(2)D(3) on MCF-7 cells. For comparison, we included studies in MCF-7 cells selected for vitamin D resistance and in human mammary epithelial cells transformed with SV40 and ras.

Parotid sialosis: morphometrical analysis of the glandular parenchyme and stroma among diabetic and alcoholic patients.

Background: Among the agents that cause parotid sialosis, diabetes mellitus type 2 and chronic alcoholism are included. In this study, the morphometrical modifications in the diabetic parotid sialosis were determined to compare them with the histopathological characteristics of alcoholic parotid sialosis.

Methods: Five parotid biopsy samples obtained from patients with diabetic sialosis, 12 samples from patients with alcoholic sialosis and seven from individuals without these pathologies (control group) were analyzed.

Morphometric analysis of the parotid gland affected by alcoholic sialosis.

Background: In alcoholic parotid sialosis, the gland is frequently enlarged due to ductal and/or acinar hypertrophy, ductal hyperplasy and stromal fat infiltration. The aim of this study was to determine acinar and ductal dimensions, the number of striated ducts and the proportion of fat tissue in patients with and without alcoholic parotid sialosis.

Methods: Twelve parotid biopsy samples from patients with hepatic alcoholic cirrhosis and those from seven controls were used.

[Molecular aspects of antineoplasic action of vitamin D].

The effects of the environment, particularly dietary factors, may influence in the development and prevention of cancer. Vitamin D (colecalciferol) has been associated for years with calcium homeostasis regulation, but many epidemiological, biochemical and genetic studies reveal non classic effects of vitamin D, such as vitamin D involvement in the progression of different types of cancer. The aim of the present article was to give a review about the molecular mechanisms of the antineoplasic action of vitamin D.