The development of experimental allergic encephalomyelitis with immunizing doses of myelin basic protein.

Rabbits immunized with low (11.25 mg) and high (57.50 mg) doses of myelin basic protein from several species develop antibasic protein antibodies, delayed type hypersensitivity, and clinical and pathological signs of experimental allergic encephalomyelitis. More than 55% of rabbits immunized with relatively high doses of basic protein develop disease. The absence of circulating antibasic protein antibodies in immunorespondent animals is associated with the appearance of clinical or histological signs of experimental allergic encephalomyelitis; however, the presence of humoral antibodies did not prevent completely the development of disease. Delayed-type hypersensitivity, specific for the basic protein, appears as early as 5 days after immunization and is maintained in nondiseased and surviving animals. Neither excess encephalitogen nor encephalitogen-induced antibody is sufficient to suppress completely the eventual development of clinical or histological manifestations of disease.     

Studies on closure of the ductus arteriosus. XII. effect of indomethacin and sodium salicylate in rats and rabbits

Administration of prostaglandin synthetase inhibitors to pregnant does and dams in late gestation was followed by contraction of the fetal ductus arteriosus when studied by the whole-body freezing method. In the rat this contraction was well established within 6 h and persisted up to 36 h following 15 mg/kg indomethacin p.o. No effect was observed in the 18 d rat fetus but fetuses at 20 d and 22 d of gestation responded significantly to indomethacin. Doses of indomethacin approaching clinical usage (2.5 mg/kg) also caused a positive response . The rat was found to be sensitive also to sodium salicylate and in the rabbit both indomethacin and sodium salicylate were effective. Exposure to prostaglandin synthetase inhibitors with resulting contraction of the ductus may seriously disturb cardiac function in the fetus.     

Stromal-cell-derived factor (SDF) 1-alpha in combination with BMP-2 and TGF-β1 induces site-directed cell homing and osteogenic and chondrogenic differentiation for tissue engineering without the requirement for cell seeding

The clinical translation of tissue engineering approaches is limited by the requirement of a cell source. Cell guidance is a new concept that provides an alternative approach, obviating a requirement for an external cell source. This relies on site-specific homing and differentiation of the patient??s own cells to an implanted scaffold through controlled delivery of cytokines. In this study, we used stromal-cell-derived factor 1-alpha (SDF-1??) in combination with bone morphogenic protein (BMP)-2 or transforming growth factor (TGF)-??1 to induce cell migration and osteogenic or chondrogenic differentiation, respectively, in implanted scaffolds in a rat model. A customized cytokine microdelivery apparatus was used to ensure the constant rate and concentration of cytokine delivery around the scaffold. The formation of osteoid or early cartilage was observed after 4?weeks in specimens treated with SDF-1?? and either BMP-2 or TGF-??1. The density of cellular infiltrate and formation of differentiated tissue were lower in scaffolds treated only with BMP-2 or TGF-??1. Thus, controlled SDF-1?? delivery induces cell migration into scaffolds and can result in enhanced osteogenesis and chondrogenesis when used in combination with differentiation cytokines for purposes of tissue engineering.     

The human–primate interface in the New Normal: Challenges and opportunities for primatologists in the COVID-19 era and beyond

The emergence of SARS-CoV-2 in late 2019 and human responses to the resulting COVID-19 pandemic in early 2020 have rapidly changed many aspects of human behavior, including our interactions with wildlife. In this commentary, we identify challenges and opportunities at human–primate interfaces in light of COVID-19, focusing on examples from Asia, and make recommendations for researchers working with wild primates to reduce zoonosis risk and leverage research opportunities. First, we briefly review the evidence for zoonotic origins of SARS-CoV-2 and discuss risks of zoonosis at the human–primate interface. We then identify challenges that the pandemic has caused for primates, including reduced nutrition, increased intraspecific competition, and increased poaching risk, as well as challenges facing primatologists, including lost research opportunities. Subsequently, we highlight opportunities arising from pandemic-related lockdowns and public health messaging, including opportunities to reduce the intensity of problematic human–primate interfaces, opportunities to reduce the risk of zoonosis between humans and primates, opportunities to reduce legal and illegal trade in primates, new opportunities for research on human–primate interfaces, and opportunities for community education. Finally, we recommend specific actions that primatologists should take to reduce contact and aggression between humans and primates, to reduce demand for primates as pets, to reduce risks of zoonosis in the context of field research, and to improve understanding of human–primate interfaces. Reducing the risk of zoonosis and promoting the well-being of humans and primates at our interfaces will require substantial changes from “business as usual.” We encourage primatologists to help lead the way.     

Forecasting intensifying disturbance effects on coral reefs

Anticipating future changes of an ecosystem's dynamics requires knowledge of how its key communities respond to current environmental regimes. The Great Barrier Reef (GBR) is under threat, with rapid changes of its reef‐building hard coral (HC) community structure already evident across broad spatial scales. While several underlying relationships between HC and multiple disturbances have been documented, responses of other benthic communities to disturbances are not well understood. Here we used statistical modelling to explore the effects of broad‐scale climate‐related disturbances on benthic communities to predict their structure under scenarios of increasing disturbance frequency. We parameterized a multivariate model using the composition of benthic communities estimated by 145,000 observations from the northern GBR between 2012 and 2017. During this time, surveyed reefs were variously impacted by two tropical cyclones and two heat stress events that resulted in extensive HC mortality. This unprecedented sequence of disturbances was used to estimate the effects of discrete versus interacting disturbances on the compositional structure of HC, soft corals (SC) and algae. Discrete disturbances increased the prevalence of algae relative to HC while the interaction between cyclones and heat stress was the main driver of the increase in SC relative to algae and HC. Predictions from disturbance scenarios included relative increases in algae versus SC that varied by the frequency and types of disturbance interactions. However, high uncertainty of compositional changes in the presence of several disturbances shows that responses of algae and SC to the decline in HC needs further research. Better understanding of the effects of multiple disturbances on benthic communities as a whole is essential for predicting the future status of coral reefs and managing them in the light of new environmental regimes. The approach we develop here opens new opportunities for reaching this goal.