Human Pluripotent Stem Cell-Derived Retinal Organoids:A Viable Platform for Investigating the Efficacy of Adeno-Associated Virus Gene Therapy

With recent advances in adeno-associated virus (AAV)-based gene therapy, efficacy and toxicity screening have become essential for developing gene therapeutic drugs for retinal diseases. Retinal organoids from human pluripotent stem cells (hPSCs) offer a more accessible and reproducible human test platform for evaluating AAV-based gene therapy.In this study, hPSCs were differentiated into retinal organoids composed of various types of retinal cells. The transduction efficiencies of AAV2 and AAV8, which are widely used in clinical trials of inherited retinal diseases, were analyzed using retinal organoids. These results suggest that retinal organoids derived from hPSCs serve as suitable screening platforms owing to their diverse retinal cell types and similarity to the human retina. In summary, we propose an optimal stepwise protocol that includes the generation of retinal organoids and analysis of AAV transduction efficacy, providing a comprehensive approach for evaluating AAV-based gene therapy for retinal diseases.

Long-Term Expansion of Functional Human Pluripotent Stem Cell-Derived Hepatic Organoids

A human cell-based liver model capable of long-term expansion and mature hepatic function is a fundamental requirement for pre-clinical drug development. We previously established self-renewing and functionally mature human pluripotent stem cell-derived liver organoids as an alternate to primary human hepatocytes. In this study, we tested long-term prolonged culture of organoids to increase their maturity. Organoid growing at the edge of Matrigel started to deteriorate two weeks after culturing, and the expression levels of the functional mature hepatocyte marker ALB were decreased at four weeks of culture. Replating the organoids weekly at a 1：2 ratio in fresh Matrigel, resulted in healthier morphology with a thicker layer compared to organoids maintained on the same Matrigel and significantly increased ALB expression until three weeks, although, it decreased sharply at four weeks. The levels of the fetal hepatocyte marker AFP were considerably increased in long-term cultures of organoids. Therefore, we performed serial passaging of organoids, whereby they were mechanically split weekly at a 1：3∼1：5 ratio in fresh Matrigel. The organoids expanded so far over passage 55, or 1 year, without growth retardation and maintained a normal karyotype after long-term cryopreservation. Differentiation potentials were maintained or increased after long-term passaging, while AFP expression considerably decreased after passaging. Therefore, these data demonstrate that organoids can be exponentially expanded by serial passaging, while maintaining long-term functional maturation potential. Thus, hepatic organoids can be a practical and renewable cell source for human cell-based and personalized 3D liver models.

Upregulation of mitochondrial NAD⁺ levels impairs the clonogenicity of SSEA1⁺ glioblastoma tumor-initiating cells

Emerging evidence has emphasized the importance of cancer therapies targeting an abnormal metabolic state of tumor-initiating cells (TICs) in which they retain stem cell-like phenotypes and nicotinamide adenine dinucleotide (NAD⁺) metabolism. However, the functional role of NAD⁺ metabolism in regulating the characteristics of TICs is not known. In this study, we provide evidence that the mitochondrial NAD⁺ levels affect the characteristics of glioma-driven SSEA1⁺ TICs, including clonogenic growth potential. An increase in the mitochondrial NAD⁺ levels by the overexpression of the mitochondrial enzyme nicotinamide nucleotide transhydrogenase (NNT) significantly suppressed the sphere-forming ability and induced differentiation of TICs, suggesting a loss of the characteristics of TICs. In addition, increased SIRT3 activity and reduced lactate production, which are mainly observed in healthy and young cells, appeared following NNT-overexpressed TICs. Moreover, in vivo tumorigenic potential was substantially abolished by NNT overexpression. Conversely, the short interfering RNA-mediated knockdown of NNT facilitated the maintenance of TIC characteristics, as evidenced by the increased numbers of large tumor spheres and in vivo tumorigenic potential. Our results demonstrated that targeting the maintenance of healthy mitochondria with increased mitochondrial NAD⁺ levels and SIRT3 activity could be a promising strategy for abolishing the development of TICs as a new therapeutic approach to treating aging-associated tumors.

Bawu decoction () ameliorates benign prostatic hyperplasia in rats / 中国结合医学杂志

<p><b>OBJECTIVE</b>To evaluate the efficacy of Bawu Decoction (, BWD, Palmul-tang in Korean) against benign prostatic hyperplasia (BPH).</p><p><b>METHODS</b>Twenty-four male Wistar rats were divided into 4 groups, with 6 rats in each group. The 4 study groups included sham-operated group (CON), BPH model group, fifinasteride-treated group, and BWD-treated group. All the groups except CON group received a subcutaneous injection of 10 mg/kg of testosterone, while CON group received saline. Finasteride at a dose of 5 mg/kg was administered to the finasteride-treated group for a period of 4 weeks. BWD group received BWD at a dose of 200 mg/kg for 4 weeks. The prostatic weight, prostate weight to body weight ratio, relative prostate weight ratio, serum testosterone and dihydrotestosterone (DHT) level, and histological analysis of prostatic tissue were analyzed.</p><p><b>RESULTS</b>Compared to BPH model group, BWD administration was associated with reductions in prostatic weight, prostate and relative prostate weight ratio weight to body weight ratio (P<0.05). The concentration of serum testosterone and DHT were higher in BPH group compared with CON group (P<0.05). Administration of finasteride and BWD suppressed the elevation of serum testosterone and DHT levels signifificantly (both P<0.05). In addition, BWD suppressed the growth of prostatic tissue (P<0.05).</p><p><b>CONCLUSION</b>BWD has suppressant effects on development of BPH through inhibition of serum testosterone and DHT.</p>

The role of NK cell in heart-lung transplanted mice / 대한이식학회지

No abstract available.

Pulmonary Insufficiency after Maasive Blood Transfusion - Case report / 대한마취과학회지

Massive blood transfusion may be defined as the acute administration of blood more than one and a half times the patient's estimated blood volume. When stored whole blood is infused, complications such as coagulation defect, volume overload, acid base disturbance and pulmonary complications will develop. Massive transfusion has been associated with the development of adult respiratory distress syndrome(ARDS) in man, and both humoral factor and microemboli have been proposed as the injurious agent in the transfused blood. WE experiecned the patient who had suffered from acute respiratory failure after the transfusion of massive amount of whole blood and managed him effectively with ventilatory support with positive end expiratory pressure under the monitoring of cardiopulmonary function via the Swan-Ganz Catheter at ICU.

Airway Obstrnction During Endotracheal Anesthesia - Case report / 대한마취과학회지

Airway obstruction following endotracheal intubation may be fraught with danger. Foreign bodies often become lodged in the airway as a result of trauma or rupture of lung lession. Somtiems they are revealed at the time of respiratory obstruction. Injury to individual mass lession is not seen so often. We experienced two cases of airway obstruction due to dislodging of foreign bodies. By exchanging obstructed endotracheal tube or removal of extracted teeth with aid of bronchoscope, the patency of the airway could secured. The aim of this case report is to emphasize that the insertion of an endotrahceal tube does not completely guarantee the patency of the airway.