Adult stem cell therapy for the treatment of tendon injuries is a growing area of research. This study is aimed to investigate the efficacy of human adipose-derived stem cell (hADSC) injection on the tendon during its healing process in a rat model of rotator cuff injury. hADSCs were injected 3 days after collagenase-induced rotator cuff injuries in experimental groups, while the control group received saline as a placebo. Histological and biomechanical analyses were performed 7, 14, 21, and 28 days after collagenase injection. Compared to the control group, it was found that inflammatory cells were significantly decreased in the hADSC-treated group after collagenase injection for 7 and 14 days. In the hADSC-injected group, the fiber arrangement and tendon organization had also been improved. On the seventh day after collagenase injection, the load to failure of the hADSC-injected group (15.87 ± 2.20 N) was notably higher than that of the saline-injected group (11.20 ± 1.35 N). It is suggested that the tensile strength of the supraspinatus tendon was significantly enhanced. Local administration of hADSCs might have the possibility to restore the tensile strength and attenuate the progression of tendinitis. Taken together, these findings demonstrate that the recovery processes in damaged tendons can be facilitated architecturally and functionally after hADSC injection.

Neurodegenerative diseases represent a significant unmet medical need in our aging society. There are no effective treatments for most of these diseases, and we know comparatively little regarding pathogenic mechanisms. Among the challenges faced by those involved in developing therapeutic drugs for neurodegenerative diseases, the syndromes are often complex, and small animal models do not fully recapitulate the unique features of the human nervous system. Human induced pluripotent stem cells (iPSCs) are a novel technology that ideally would permit us to generate neuronal cells from individual patients, thereby eliminating the problem of species-specificity inherent when using animal models. Specific phenotypes of iPSC-derived cells may permit researchers to identify sub-types and to distinguish among unique clusters and groups. Recently, iPSCs were used for drug screening and testing for neurologic disorders including Alzheimer’s disease (AD), amyotrophic lateral sclerosis (ALS), spinocerebellar atrophy (SCA), and Zika virus infection. However, there remain many challenges still ahead, including how one might effectively recapitulate sporadic disease phenotypes and the selection of ideal phenotypes and for large-scale drug screening. Fortunately, quite a few novel strategies have been developed that might be combined with an iPSC-based model to solve these challenges, including organoid technology, single-cell RNA sequencing, genome editing, and deep learning artificial intelligence. Here, we will review current applications and potential future directions for iPSC-based neurodegenerative disease models for critical drug screening.

Hydrocortisone did not significantly reduce the incidence of postextubation laryngeal edema or stridor. From the risk factors evaluated, we were unable to demonstrate a statistical correlation between postextubation stidor and the duration of the intubation, the patient's age, the internal diameter of the endotracheal tube, or the route of intubation. However, female patients were more likely to develop this complication.