A modified rehabilitation paradigm bilaterally increased rat extensor digitorum communis muscle size but did not improve forelimb function after stroke

Malnutrition after stroke may lessen the beneficial effects of rehabilitation on motor recovery through influences on both brain and skeletal muscle. Enriched rehabilitation (ER), a combination of environmental enrichment and forelimb reaching practice, is used preclinically to study recovery of skilled reaching after stroke. However, the chronic food restriction typically used to motivate engagement in reaching practice is a barrier to using ER to investigate interactions between nutritional status and rehabilitation. Thus, our objectives were to determine if a modified ER program comprised of environmental enrichment and skilled reaching practice motivated by a short fast would enhance post-stroke forelimb motor recovery and preserve forelimb muscle size and metabolic fiber type, relative to a group exposed to stroke without ER. At one week after photothrombotic cortical stroke, male, Sprague-Dawley rats were assigned to modified ER or standard care for 2 weeks. Forelimb recovery was assessed in the Montoya staircase and cylinder task before stroke and on days 5-6, 22-23, and 33-34 after stroke. ER failed to improve forelimb function in either task (p > 0.05). Atrophy of extensor digitorum communis (EDC) and triceps brachii long head (TBL) muscles was not evident in the stroke-targeted forelimb on day 35, but the area occupied by hybrid fibers was increased in the EDC muscle (p = 0.038). ER bilaterally increased EDC (p = 0.046), but not TBL, muscle size; EDC muscle fiber type was unchanged by ER. While the modified ER did not promote forelimb motor recovery, it does appear to have utility for studying the role of skeletal muscle plasticity in post-stroke recovery.

Antioxidant Effect and Acute Oral Toxicity of Hot Springs

According to the research, there are many illnesses for which therapeutic mineral hot springs are employed as an alternative. Its physicochemical characteristics have a substantial body of evidence. The in vivo antioxidant effect of Mosul's hot springs in Iraq has been investigated in the current investigation. An experimental design for toxicity, a control group, and a study group were created. In addition, in vivo antioxidant effect of the hot springs of Mosul, Iraq, has been studied by the lipid antiperoxidation method with (p < 0.05), in vitro by the free radical scavenging method (DPPH) for its complexing capacity of hot springs. In acute oral toxicity in vivo at fixed doses, looking for signs and symptoms of toxicity, there are no signs of intoxication or significant changes in the biochemical analysis (blood count). And, it was discovered that the variances are substantial. The animal was necropsied, and hematological and biochemical parameters were determined, as well as the organs' histological processing at the study's conclusion. It was found that the thermal waters from Mosul, Iraq, are medicinal mineral waters, chlorinated, sodium, and sulfated, nontoxic and have an antioxidant effect. With the help of the research's findings, it is hoped to provide scientific support for knowledge that, when made public, encourages the development of Mosul's hot springs as a safe and environmentally friendly tourist destination. With the results of this research, the parameters were presented with their mean and standard deviation statistics, promoting the ecological and sanitary tourism development of the Mosul hot springs, which will generate more significant income for the population, therefore growth in the region.

Environmental Enrichment for Rats and Mice Housed in Laboratories: A Metareview

Simple Summary

Environmental enrichment has been widely studied with laboratory rodents, but there is no consensus regarding what counts as enrichment or what it should achieve. Inconsistent use of the term “enrichment” creates challenges in drawing conclusions about the quality of an environment. We conducted a metareview to better understand the definitions and goals of enrichment, perceived risks or requirements of enrichment, and what forms of enrichment have previously been endorsed for use with rodents housed in laboratories. This may help researchers and animal care staff to better define their chosen approach and intended outcomes when providing environmental enrichment.

Abstract

Environmental enrichment has been widely studied in rodents, but there is no consensus on what enrichment should look like or what it should achieve. Inconsistent use of the term “enrichment” creates challenges in drawing conclusions about the quality of an environment, which may slow housing improvements for laboratory animals. Many review articles have addressed environmental enrichment for laboratory rats and mice (Rattus norvegicus and Mus musculus). We conducted a metareview of 29 review articles to assess how enrichment has been defined and what are commonly described as its goals or requirements. Recommendations from each article were summarised to illustrate the conditions generally considered suitable for laboratory rodents. While there is no consensus on alternative terminology, many articles acknowledged that the blanket use of the terms “enriched” and “enrichment” should be avoided. Environmental enrichment was most often conceptualised as a method to increase natural behaviour and improve animal welfare. Authors also commonly outlined perceived risks and requirements of environmental enrichment. We discuss these perceptions, make suggestions for future research, and advocate for the adoption of more specific and value-neutral terminology.

3D printing of human ear pinna using cartilage specific ink

Biofabrication of a complex structure such as ear pinna is not precise with currently available techniques. Auricular deformities (e.g. microtia) can cause physical, social as well as psychological impacts on a patient's wellbeing. Currently available surgical techniques and transplantation methods have many limitations that can be overcome with the help of 3D bioprinting technology. Printable bioink enriched with cartilage-specific extracellular matrix (ECM) synthesis was done by digesting goat ear pinna cartilage and polymerized by adding polyvinyl alcohol and gelatine. Rheological analysis and Fourier-transform infrared spectroscopy were used for the characterization of bioink to get desired viscosity and polymerization. Human ear pinna was printed using extrusion method and computer-aided design, stereolithography software which facilitated the automated printing in relatively less time without continuous monitoring. Thermal degradation of pinna was checked by thermal gravimetric analysis. Biodegradability and swelling of ear pinna were observed for understanding the nature of pinna and the impact of external factors. Reconstructed pinna's biocompatibility was proved byin ovoandin vivostudies. The occurrence of angiogenesis in the grafted ear manifested the capacity of proliferation and engraftment of cartilage cells. Histology and SEM analysis revealed the recellularization and the synthesis of ECM components such as glycosaminoglycan and collagen in transplanted 3D printed ear pinna. The expression of CD90+ which indicated newly synthesized cartilage in the transplanted 3D printed ear pinna. The absence expression of CD14+ also indicated acceptance of xenogenic transplanted 3D printed ear pinna. Transplantation of 3D ear pinna was successful in an animal model and can be utilized as tissue engineered ear bank.

Long Term Physiologic and Behavioural Effects of Housing Density and Environmental Resource Provision for Adult Male and Female Sprague Dawley Rats

There is considerable interest in refining laboratory rodent environments to promote animal well-being, as well as research reproducibility. Few studies have evaluated the long term impact of enhancing rodent environments with resources and additional cagemates. To that end, male and female Sprague Dawley (SD) rats were housed singly (n = 8/sex), in pairs (n = 16/sex), or in groups of four (n = 16/sex) for five months. Single and paired rats were housed in standard cages with a nylon chew toy, while group-housed rats were kept in double-wide cages with two PVC shelters and a nylon chew toy and were provided with food enrichment three times weekly. Animal behaviour, tests of anxiety (open field, elevated plus maze, and thermal nociception), and aspects of animal physiology (fecal corticoid levels, body weight, weekly food consumption, organ weights, and cerebral stress signaling peptide and receptor mRNA levels) were measured. Significant differences were noted, primarily in behavioural data, with sustained positive social interactions and engagement with environmental resources noted throughout the study. These results suggest that modest enhancements in the environment of both male and female SD rats may be beneficial to their well-being, while introducing minimal variation in other aspects of behavioural or physiologic responses.

Effects of Metabolic Cage Housing on Rat Behavior and Performance in the Social Interaction Test

Although the metabolic cage is commonly used for housing nonhuman animals in the laboratory, it has been recognized as constituting a unique stressor. Such an environment would be expected to affect behavioral change in animals housed therein. However, few studies have specifically addressed the nature or magnitude of this change. The current study sought to characterize the behavioral time budget of rats in metabolic cage housing in comparison to that of individually housed animals in standard open-top cages. Rats in metabolic cages spent less time moving, manipulating enrichment, and carrying out rearing behaviors, and there was a corresponding shift toward inactivity. In an applied Social Interaction Test, behavioral scoring implied that metabolic cage housing had an anxiogenic effect. In conclusion, metabolic cage housing produces measurable effects on spontaneous and evoked behavior in rats in the laboratory. These behavioral changes may lead to a negative emotional state in these animals, which could have negative welfare consequences. Further research is needed to quantify the existence and magnitude of such an effect on rat well being.