Intervertebral disc degeneration is associated with diverse spine diseases, including spinal stenosis, facet arthropathy, and disc herniation, which have socio-economic effects. A normal intervertebral disc has consistency and homeostasis, consisting of annulus fibrosus, nucleus pulposus, notochordal cells, nucleus pulposus cells, and an endplate with an immune privilege. On the other hand, when the degenerative process has pathologic causes, the inflammatory reaction could lead to nerve sprouting and vascularization into the tissue. Histopathologically, the pathologic process involves the degradation of the extracellular matrix, apoptosis and necrosis of nucleus pulposus cells, inhibition of chondrogenic differentiation, disruption of endplate chondrogenic cells, and other processes. Various approaches for managing disc degeneration have been reported. Among them, mesenchymal stem cells (MSCs) have been regarded as representative trials. In vitro and animal studies with MSCs have reported some promising outcomes in terms of inflammatory modulation and regeneration, but several limitations have been pointed out, including the issues of graft rejection and survival. Because the paracrine mechanism would be a main therapeutic factor of MSCs, extracellular vesicles (EVs), one of the factors released from MSCs, have been considered a promising source for regenerative medicine. EVs possess nucleic acids, functional proteins, and inflammation-related factors, playing a significant role in the inflammatory reaction and regeneration. The current review article discusses the pathophysiology of disc degeneration, outcomes of conventional MSCs and EVs, and current limitations and future perspectives on EV therapeutics.

Intervertebral disc degeneration is associated with diverse spine diseases, including spinal stenosis, facet arthropathy, and disc herniation, which have socio-economic effects. A normal intervertebral disc has consistency and homeostasis, consisting of annulus fibrosus, nucleus pulposus, notochordal cells, nucleus pulposus cells, and an endplate with an immune privilege. On the other hand, when the degenerative process has pathologic causes, the inflammatory reaction could lead to nerve sprouting and vascularization into the tissue. Histopathologically, the pathologic process involves the degradation of the extracellular matrix, apoptosis and necrosis of nucleus pulposus cells, inhibition of chondrogenic differentiation, disruption of endplate chondrogenic cells, and other processes. Various approaches for managing disc degeneration have been reported. Among them, mesenchymal stem cells (MSCs) have been regarded as representative trials. In vitro and animal studies with MSCs have reported some promising outcomes in terms of inflammatory modulation and regeneration, but several limitations have been pointed out, including the issues of graft rejection and survival. Because the paracrine mechanism would be a main therapeutic factor of MSCs, extracellular vesicles (EVs), one of the factors released from MSCs, have been considered a promising source for regenerative medicine. EVs possess nucleic acids, functional proteins, and inflammation-related factors, playing a significant role in the inflammatory reaction and regeneration. The current review article discusses the pathophysiology of disc degeneration, outcomes of conventional MSCs and EVs, and current limitations and future perspectives on EV therapeutics.

Intervertebral disc degeneration is associated with diverse spine diseases, including spinal stenosis, facet arthropathy, and disc herniation, which have socio-economic effects. A normal intervertebral disc has consistency and homeostasis, consisting of annulus fibrosus, nucleus pulposus, notochordal cells, nucleus pulposus cells, and an endplate with an immune privilege. On the other hand, when the degenerative process has pathologic causes, the inflammatory reaction could lead to nerve sprouting and vascularization into the tissue. Histopathologically, the pathologic process involves the degradation of the extracellular matrix, apoptosis and necrosis of nucleus pulposus cells, inhibition of chondrogenic differentiation, disruption of endplate chondrogenic cells, and other processes. Various approaches for managing disc degeneration have been reported. Among them, mesenchymal stem cells (MSCs) have been regarded as representative trials. In vitro and animal studies with MSCs have reported some promising outcomes in terms of inflammatory modulation and regeneration, but several limitations have been pointed out, including the issues of graft rejection and survival. Because the paracrine mechanism would be a main therapeutic factor of MSCs, extracellular vesicles (EVs), one of the factors released from MSCs, have been considered a promising source for regenerative medicine. EVs possess nucleic acids, functional proteins, and inflammation-related factors, playing a significant role in the inflammatory reaction and regeneration. The current review article discusses the pathophysiology of disc degeneration, outcomes of conventional MSCs and EVs, and current limitations and future perspectives on EV therapeutics.

A noncontact sensor field is an innovative device that can detect, measure, or monitor physical properties or conditions without direct physical contact with the subject or object under examination. These sensors use a variety of methods, including electromagnetic, optical, and acoustic technique, to collect information about the target without physical interaction. Noncontact sensors find wide-ranging applications in various fields such as manufacturing, robotics, automobiles, security, environmental monitoring, space industry, agriculture, and entertainment. In particular, they are used in the medical field, where they provide continuous monitoring of patient conditions and offer opportunities in rehabilitation medicine. This article introduces the potential of noncontact sensors in the field of rehabilitation medicine.

Background/Aims: Since the coronavirus disease 2019 (COVID-19) outbreak, hospitals have implemented infection control measures to minimize the spread of the virus within facilities. This study aimed to investigate the impact of COVID-19 on the incidence of healthcare-associated infections (HCAIs) and common respiratory virus (cRV) infections in hematology units. Methods: This retrospective study included all patients hospitalized in Catholic Hematology Hospital between 2019 and 2020. Patients infected with vancomycin-resistant Enterococci (VRE), carbapenemase-producing Enterobacterales (CPE), Clostridium difficile infection (CDI), and cRV were analyzed. The incidence rate ratio (IRR) methods and interrupted time series analyses were performed to compare the incidence rates before and after the pandemic. Results: The incidence rates of CPE and VRE did not differ between the two periods. However, the incidence of CDI increased significantly (IRR: 1.41 [p = 0.002]) after the COVID-19 pandemic. The incidence of cRV infection decreased by 76% after the COVID-19 outbreak (IRR: 0.240 [p < 0.001]). The incidence of adenovirus, parainfluenza virus, and rhinovirus infection significantly decreased in the COVID-19 period (IRRs: 0.087 [p = 0.003], 0.031 [p < 0.001], and 0.149 [p < 0.001], respectively). Conclusions The implementation of COVID-19 infection control measures reduced the incidence of cRV infection. However, CDI increased significantly and incidence rates of CPE and VRE remained unchanged in hematological patients after the pandemic. Infection control measures suitable for each type of HCAI, such as stringent hand washing for CDI and enough isolation capacities, should be implemented and maintained in future pandemics, especially in immunocompromised patients.

Purpose: Firefighting duties range from field roles such as suppression, rescue, and emergency medical services (EMS) to various administrative tasks. Despite these differences, they face uniform fitness standards in Korea. This study seeks to define distinct fitness needs for each duty and provide data for customized standards. Methods: One hundred seventy-six Korean male firefighters participated, categorized into suppression (n=76), rescue (n=22), administrative (n=27), and EMS (n=51) roles. All underwent maximal oxygen consumption (VO2 max) tests for aerobic capacity, with body composition measured using bioelectrical impedance and height recorded with a stadiometer. Results: The VO2 max (mL/kg/min) among Korean male firefighters varied across different job duties: suppression (39.96±5.84), rescue (44.84±4.85), administration (40.27±7.01), and EMS (40.51±6.75). Rescue had the highest VO2 max, which was significantly higher (p=0.013). The body mass index (BMI, kg/m2 ) values were as follows: suppression (25.07±2.55), rescue (24.95±1.71), EMS (24.33±3.21), and administration (25.10±2.48). There was no statistically significant difference in BMI values (p=0.464). Conclusion This study evaluated the VO2 max and BMI of South Korean male firefighters according to their job duties. It found that 54.5% did not meet the recommended VO2 max standard of 42 mL/kg/min for their activities, and 77.5% had a BMI indicating overweight or higher. However, it is important to note that not every firefighting duty requires high fitness levels. The key is ensuring firefighters possess the fitness necessary for their specific roles to maintain safety and efficiency. The study aims to provide data for creating fitness management guidelines tailored to the diverse duties of firefighters.

Background: Cage subsidence after oblique lumbar interbody fusion (OLIF) induces restenosis and adversely affects patient outcomes. Many studies have investigated the causes of subsidence, one of which is endplate fracture (EF). This study aimed to identify predictors of EF after OLIF. Methods: This retrospective study reviewed consecutive patients who underwent OLIF at a single institute between August 2019 and February 2022. A total of 104 patients were enrolled. The patients’ demographic data and surgical details were collected through chart reviews. Radiographic variables were measured. Related variables were also analyzed using binomial logistic regression, dividing each group into those with versus without EF. Results: EF occurred at 30 of 164 levels (18.3%), and the binary logistic analysis revealed that sex (odds ratio [OR], 11.07), inferior endplate concave depth (OR, 1.95), disc wedge angle (OR, 1.22), lumbar lordosis (OR, 1.09), pelvic incidence (OR, 1.07), sagittal vertical axis (OR, 1.02), sacral slope (OR, 0.9), L3–4 level (OR, 0.005), and L4–5 level (OR, 0.004) were significantly related to EF. Conclusions OLIF in older Asian patients should be performed carefully after recognizing the high possibility of EF and confirming the factors that should be considered preoperatively.

Mental health is influenced by the gut-brain axis; for example, gut dysbiosis has been observed in patients with major depressive disorder (MDD).Gut microbial changes by fecal microbiota transplantation or probiotics treatment reportedly modulates depressive symptoms. However, it remains unclear how gut dysbiosis contributes to mental dysfunction, and how correction of the gut microbiota alleviates neuropsychiatric disorders. Our previous study showed that chronic consumption of Lactobacillus reuteri ATG-F4 (F4) induced neurometabolic alterations in healthy mice. Here, we investigated whether F4 exerted therapeutic effects on depressive-like behavior by influencing the central nervous system. Using chronic unpredictable stress (CUS) to induce anhedonia, a key symptom of MDD, we found that chronic F4 consumption alleviated CUS-induced anhedonic behaviors, accompanied by biochemical changes in the gut, serum, and brain. Serum and brain metabolite concentrations involved in tryptophan metabolism were regulated by CUS and F4. F4 consumption reduced the elevated levels of serotonin (5-HT) in the brain observed in the CUS group. Additionally, the increased expression of Htr1a, a subtype of the 5-HT receptor, in the medial prefrontal cortex (mPFC) of stressed mice was restored to levels observed in stress-naïve mice following F4 supplementation. We further demonstrated the role of Htr1a using AAV-shRNA to downregulate Htr1a in the mPFC of CUS mice, effectively reversing CUS-induced anhedonic behavior. Together, our findings suggest F4 as a potential therapeutic approach for relieving some depressive symptoms and highlight the involvement of the tryptophan metabolism in mitigating CUS-induced depressive-like behaviors through the action of this bacterium.

Background and Objectives: This work investigates the clinical characteristics of benign paroxysmal positional vertigo (BPPV) according to etiology by comparing idiopathic BPPV (iBPPV), BPPV occurring after head trauma (tBPPV) and BPPV associated with idiopathic sudden sensory neural hearing loss (sBPPV).Subjects and Method A total of 869 patients who were diagnosed and treated for BPPV were reviewed retrospectively. Patients were divided into three groups according to the probable etiology of BPPV: iBPPV vs. tBPPV vs. sBPPV. We investigated and compared demographics, the affected sides and canals, the number of canalith repositioning procedure (CRP) performed to achieve successful reposition, canal conversion and recurrence among the three groups. Among the three groups, BPPV patients who performed caloric test and/or video head impulse test (vHIT) were additionally evaluated and compared. Results: The iBPPV group (n=787) had greater female preponderance (72%, 567/787) than the tBPPV (n=51) and sBPPV groups (n=31, p<0.001). The mean number of CRPs needed for successful repositioning in the iBPPV group (1.40±0.03) was significantly (p<0.001) lower than that in the tBPPV and sBPPV groups (2.04±0.24 and 2.45±0.36). There was no difference between the tBPPV and sBPPV groups. Recurrence rate was not significantly different among three groups (14.6% vs. 17.7% vs. 16.2%) statistically. The presence of canal paresis and abnormal results of vHIT test were not related with a greater number of CRPs required and recurrence. Conclusion More CRPs were required for successful repositioning in the tBPPV and sBPPV patients than in the iBPPV patients and there was no difference between tBPPV and sBPPV patients. Recurrence rate was not different among the three groups. This information may be helpful for clinicians in counselling and managing BPPV patients.

Background: Ultrasonography (US) is a simple and reliable tool that can aid in the diagnosis of benign subcutaneous lesions such as epidermal cysts and lipomas. Objective: This study aimed to determine the efficacy of US for the differential diagnosis of epidermal cysts and lipomas. Methods: A retrospective study of 100 patients with epidermal cysts (n=45) or lipomas (n=55) who underwent US and then received a pathological diagnosis in the dermatology department of Pusan National University Hospital was conducted. Results: US and clinical impressions accurately diagnosed the epidermal cysts in 90.0% and 88.0% of the patients, respectively, and the lipomas in 92.0% and 88.0% of the patients, respectively. US combined with clinical impression significantly increased the diagnostic yield of epidermal cysts (98%) and lipomas (99%). On US, the frequency of posterior acoustic enhancement was higher for the epidermal cysts than for the lipomas (82.2% and 29.1%, respectively; p＜0.001), and striated echoes such as internal linear echogenic reflections and dark clefts were more frequently found in the lipomas than in the epidermal cysts (90.9% and 6.7%, respectively; p＜0.001). Conclusion This study implies that the diagnostic role of US can be greatly enhanced by knowledge of the clinical presentation.