Knowledge of the incidence of clinical mastitis (CM) and the distribution of pathogens involved is essential for development of prevention and control programs as well as treatment protocols. No country-wide study on the incidence of CM and the distribution of pathogens involved has been conducted in China. Core objectives of this study were, therefore, to determine the cumulative incidence of CM and the distribution of pathogens causing CM on large Chinese (>500 cows) dairy farms. In addition, associations between the distribution of CM pathogens and bedding materials and seasonal factors were also investigated. Bacterial culture was done on a total of 3,288 CM quarter milk samples from 161 dairy herds (located in 21 provinces) between March 2014 and September 2016. Additional data, including geographical region of herds, herd size, bedding types, and number of CM cases during the last month, were also recorded. Mean cumulative incidence of CM was 3.3 cases per 100 cows per month (range = 1.7 to 8.1). The most frequently isolated pathogens were Escherichia coli (14.4%), Klebsiella spp. (13.0%), coagulase-negative staphylococci (11.3%), Streptococcus dysgalactiae (10.5%), and Staphylococcus aureus (10.2%). Streptococcus agalactiae was isolated from 2.8% of CM samples, whereas Streptococcus uberis were isolated from 2.1% of samples, and 15.8% of 3,288 samples were culture-negative. Coagulase-negative staphylococci, E. coli, and other Enterobacter spp. were more frequently isolated in the northwest than the northeast or south of China. Streptococcus dysgalactiae, other streptococci, and Strep. agalactiae were more frequently isolated in winter (October-March), whereas E. coli and Klebsiella spp. were mostly isolated in summer (April-September). Streptococcus dysgalactiae was more often isolated from CM cases of herds using sand bedding, whereas Klebsiella spp. and other streptococci were more common in herds using organic bedding. The incidence of CM and distribution of pathogens differed among herds and better mastitis management is needed. Furthermore, geography, bedding materials, and season should be included when designing mastitis control and prevention schemes for Chinese dairies.

Osteoporosis is a disorder of bone and its development is closely associated with oxidative stress and reactive oxygen species (ROS). Chlorogenic acid (CGA) has potential antioxidant effects and its pharmacological action in osteoblasts is not clearly understood. The present study aimed to clarify the protective effects and mechanisms of CGA on hydrogen peroxide (H2O2)-induced oxidative stress in osteoblast cells. MC3T3-E1 cells were treated with H2O2 to induce oxidative stress model in vitro. Cells were treated with CGA prior to H2O2 exposure, the intracellular ROS production, malondialdehyde content, nitric oxide release and glutathione level were measured. We also investigated the protein levels of heme oxygenase-1 (HO-1), the nuclear translocation of transcription factor NF-erythroid 2-related factor (Nrf2) and the phosphorylation levels of Akt in CGA-treated cells. The results showed that pretreatment of CGA could reverse the inhibition of cell viability and suppress the induced apoptosis and caspase-3 activity. Additionally, it significantly reduced H2O2-induced oxidative damage in a dose-dependent manner. Furthermore, it induced the protein expression of HO-1 together with its upstream mediator Nrf2, and activated the phosphorylation of Akt in MC3T3-E1 cells. LY294002, a PI3K/Akt inhibitor, significantly suppressed the CGA-induced Nrf2 nuclear translocation and HO-1 expression. Reduction of cell death mediated by CGA in presence of H2O2 was significantly inhibited by Zinc protoporphyrin IX (a HO-1 inhibitor) and LY294002. These data demonstrated that CGA protected MC3T3-E1 cells against oxidative damage via PI3K/Akt-mediated activation of Nrf2/HO-1 pathway, which may be an effective drug in treatment of osteoporosis.

A B S T R A C TBackground: A physiological hallmark of patients with type 2 diabetes mellitus (T2DM) is b cell dysfunction.Despite adequate treatment, it is an irreversible process that follows disease progression. Therefore, the development of novel therapies that restore b cell function is of utmost importance.Methods: This study aims to unveil the mechanistic action of mesenchymal stem cells (MSCs) by investigating its impact on isolated human T2DM islets ex vivo and in vivo.Findings: We propose that MSCs can attenuate b cell dysfunction by reversing b cell dedifferentiation in an IL-1Ra-mediated manner. In response to the elevated expression of proinflammatory cytokines in human T2DM islet cells, we observed that MSCs was activated to secret IL-1R antagonist (IL-1Ra) which acted on the inflammed islets and reversed b cell dedifferentiation, suggesting a crosstalk between MSCs and human T2DM islets. The co-transplantation of MSCs with human T2DM islets in diabetic SCID mice and intravenous infusion of MSCs in db/db mice revealed the reversal of b cell dedifferentiation and improved glycaemic control in the latter. Interpretation: This evidence highlights the potential of MSCs in future cell-based therapies regarding the amelioration of b cell dysfunction.

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Background and Objectives: Adipose tissue-derived mesenchymal stem cells (ASCs) are recognized as an advantaged source for the prevention and treatment of diverse diseases including type 2 diabetes mellitus (T2DM). However, alterations in characteristics of ASCs from the aforementioned T2DM patients are still obscure, which also hinder the rigorous and systematic illumination of progression and pathogenesis. Methods and Results: In this study, we originally isolated peripancreatic adipose tissue-derived mesenchymal stem cells from both human type 2 diabetic and non-diabetic donors (T2DM-ASCs, ND-ASCs) with the parental consent, respectively. We noticed that T2DM-ASCs exhibited indistinguishable immunophenotype, cell vitality, chondrogenic differentiation and stemness as ND-ASCs. Simultaneously, there's merely alterations in migration and immunoregulatory capacities in T2DM-ASCs. However, differing from ND-ASCs, T2DM-ASCs exhibited deficiency in adipogenic and osteogenic differentiation, and in particular, the delayed cell cycle and different cytokine expression spectrum. Conclusions: The conservative alterations of T2DM-ASCs in multifaceted characteristics indicated the possibility of autologous application of ASCs for cell-based T2DM treatment in the future.