Recent amendments to regulatory frameworks have placed a greater emphasis on the utilization of in vitro testing platforms for preclinical drug evaluations and toxicity assessments. This requires advanced tissue models capable of accurately replicating liver functions for drug efficacy and toxicity predictions. Liver organoids, derived from human cell sources, offer promise as a reliable platform for drug evaluation. However, there is a lack of standardized quality evaluation methods, which hinders their regulatory acceptance. This paper proposes comprehensive quality standards tailored for liver organoids, addressing cell source validation, organoid generation, and functional assessment. These guidelines aim to enhance reproducibility and accuracy in toxicity testing, thereby accelerating the adoption of organoids as a reliable alternative or complementary tool to animal testing in drug development. The quality standards include criteria for size, cellular composition, gene expression, and functional assays, thus ensuring a robust hepatotoxicity testing platform.

Background: Ultrasound-guided first sacral transforaminal epidural steroid injection (S1 TFESI) is a useful and easily applicable alternative to fluoroscopy or computed tomography (CT) in lumbosacral radiculopathy. When a needle approach is used, poor visualization of the needle tip reduces the accuracy of the procedure, increasing its difficulty. This study aimed to improve ultrasound-guided S1 TFESI by evaluating radiological S1 posterior foramen data obtained using three-dimensional CT (3D-CT). Methods: Axial 3D-CT images of the pelvis were retrospectively analyzed. The radiological measurements obtained from the images included 1st posterior sacral foramen depth (S1D, mm), 1st posterior sacral foramen width (S1W, mm), the angle of the 1st posterior sacral foramen (S1A, °), and 1st posterior sacral foramen distance (S1ds, mm). The relationship between the demographic factors and measured values were then analyzed. Results: A total of 632 patients (287 male and 345 female) were examined. The mean S1D values for males and females were 11.9 ± 1.9 mm and 10.6 ± 1.8 mm, respectively (P < 0.001); the mean S1A 28.2 ± 4.8° and 30.1 ± 4.9°, respectively (P < 0.001); and the mean S1ds, 24.1 ± 2.9 mm and 22.9 ± 2.6 mm, respectively (P < 0.001); however, the mean S1W values were not significantly different. Height was the only significant predictor of S1D (β =0.318, P = 0.004). Conclusions Ultrasound-guided S1 TFESI performance and safety may be improved with adjustment of needle insertion depth congruent with the patient’s height.

Background: Soft tissue fillers are increasingly used to rejuvenate and beautify the body and face. Unknown foreign materials that have not always been proven to be safe for human use have been used for injections in the past. Various commercial injectable materials have since been developed and are used; however, the number of complications has increased as soft tissue fillers have increased in use. Methods: A retrospective study of 39 patients with facial foreign body complications who underwent surgical treatment between March 2012 and February 2021 was conducted. Patient information was analyzed, and patient satisfaction was evaluated using a questionnaire after surgical treatment. A comparative statistical analysis was undertaken. Results: Patients who underwent procedures performed by unlicensed practitioners tended to be older at the time of presenting to the hospital (P=0.004). The degree of satisfaction after surgical repair was significantly lower following the direct approach than after the indirect approach using a bypass incision (P=0.044). The degree of satisfaction significantly decreased (P=0.001) as the number of operations the patient received increased. Conclusions When treating complications caused by foreign material injections, surgical removal is a more reliable method than treatment with medication or further injections; however, treatment decisions should be made thoughtfully, and many factors must be considered. Patient satisfaction can be improved by reducing the number of operations and making the appropriate corresponding incisions or excisions to treat the full range of symptoms caused by foreign substances and by indirectly using bypass incisions to mitigate post-surgery scars.

Background: Although it is known that inhaled corticosteroid (ICS) use may increase the risk of respiratory infection, its influence on the risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection remains unknown. Thus, the aim of this study was to investigate the association between ICS use and the positivity of SARS-CoV-2 infection among patients with chronic respiratory diseases. Methods: Nationwide data of 44,968 individuals with chronic respiratory diseases tested for SARS-CoV-2 until May 15, 2021 were obtained from the Ministry of Health and Welfare and Health Insurance Review and Assessment Service in Korea. The positivity of SARS-CoV-2 infection was retrospectively analysed according to the prescription, type, and dose of ICS taken one year before SARS-CoV-2 test. Results: Among 44,968 individuals tested, 931 (2.1%) were positive for SARS-CoV-2. A total of 7,019 patients (15.6%) were prescribed ICS one year prior to being tested for SARS-CoV-2. Low, medium, and high doses of ICS were prescribed in 7.5%, 1.6%, and 6.5% of total cases, respectively. Among types of ICS, budesonide, fluticasone, beclomethasone, and ciclesonide were prescribed in 3.7%, 8.9%, 2.3%, and 0.6% of total cases, respectively. A multivariate analysis showed no significant increase in infection with ICS use (odds ratio, 0.84; 95% confidence interval, 0.66–1.03). Moreover, there were no associations between the positivity of infection and the dose or type of ICS prescribed. Conclusion Prior ICS use did not increase the positivity for SARS-CoV-2 infection. Moreover, different doses or types of ICS did not affect this positivity.

The complexity in the molecular mechanism of the internal anal sphincter (IAS) limits preclinical or clinical outcomes of fecal incontinence (FI) treatment. So far, there are no systematic reviews of IAS translation and experimental studies that have been reported. This systematic review aims to provide a comprehensive understanding of IAS critical role in FI. Previous studies revealed the key pathway for basal tone and relaxation of IAS in different properties as follows; calcium, Rho-associated, coiled-coil containing serine/threonine kinase, aging-associated IAS dysfunction, oxidative stress, renin-angiotensin-aldosterone, cyclooxygenase, and inhibitory neurotransmitters. Previous studies have reported improved functional outcomes of cellular treatment for regeneration of dysfunctional IAS, using various stem cells, but did not demonstrate the interrelationship between those results and basal tone or relaxation-related molecular pathway of IAS. Furthermore, these results have lower specificity for IAS-incontinence due to the included external anal sphincter or nerve injury regardless of the cell type. An acellular approach using bioengineered IAS showed a physiologic response of basal tone and relaxation response similar to human IAS. However, in both cellular and acellular approaches, the lack of human IAS data still hampers clinical application. Therefore, the IAS regeneration presents more challenges and warrants more advances.

Background: Recently, microbiome research has been actively conducted for various skin areas. However, no study has yet compared the microbiome of bacteria and fungi in the ear canal of healthy individuals and patients with chronic otitis externa in Korea. Objective: This study aimed to investigate the difference in the distribution of fungal and bacterial microbial communities in ear canal samples of healthy individuals and patients with chronic otitis externa. Methods: In 24 patients with bilateral chronic otitis externa and 24 healthy controls, cotton swabs were used to obtain samples from the bilateral ear canal. To characterize the fungal and bacterial communities, we sequenced and analyzed the 16S rRNA V4–V5 and ITS1 regions using Quantitative Insights into Microbial Ecology 2, respectively. Results: The alpha diversity analysis for bacteria and fungi confirmed that both richness and evenness decreased in the patient group. The beta diversity analysis for bacteria confirmed that these parameters differed between the control and patient groups. The beta diversity analysis for fungi showed no difference between the groups. Conclusion We observed different skin microbiomes in the patients with chronic otitis externa compared with those in the healthy individuals.