Difference in Sugar-Sweetened Beverage Consumption before and during the COVID-19 Pandemic among Korean Adolescents.

BACKGROUND: Previous studies have identified various factors associated with sugar-sweetened beverage (SSB) consumption among children and adolescents. Recent studies attempted to analyze changes in SSB consumption of adolescents during the COVID-19 pandemic and showed conflicting results. OBJECTIVES: This study aimed to estimate the difference in SSB consumption before (2018-2019) and during (2020-2021) the COVID-19 pandemic among Korean adolescents. METHODS: The study population consisted of students (n = 227,139) aged 12-18 y from the Korean Youth Risk Behavior Web-based Survey (KYRBWS). Data collection was done between 2018 and 2021. The primary outcome was the difference in the SSB consumption status (none/<7 times/wk, ≥7 times/wk) before and during the COVID-19 pandemic. Multinomial logistic regression was used to examine the association. Additional analysises were also conducted by gender, school grades, household income, grade point average, region, household members, fast-food intake, and fruit intake. RESULTS: The COVID-19 pandemic was associated with a decrease in adolescents' SSB intake. [(<7 times/wk) 2019: 59.4, 2020: 58.8, (≥7 times/wk) 2019: 35.3, 2020: 33.4]. CONCLUSIONS: The study found a difference in SSB consumption among Korean adolescents between before and during the COVID-19 pandemic. These findings are noteworthy considering the importance of continuous care in managing SSB intake.

Single-Cell RNA Sequencing Analysis of Human Dental Pulp Stem Cell and Human Periodontal Ligament Stem Cell.

INTRODUCTION: Many studies have investigated the transcriptome profiles of dental stem cells for regenerative medicine. However, such studies use bulk RNA and do not consider cell-level heterogeneity. Here, we investigated the characteristics and heterogeneity of human dental pulp stem cells (hDPSCs) and human periodontal ligament stem cells (hPDLSCs) at the single-cell level and examined the differences between them. METHODS: hDPSCs and hPDLSCs were obtained from caries-free premolars (n = 2). Single-cell RNA sequencing of hDPSCs and hPDLSCs was performed using a Single Emulsion Systems (Dolomite Microfluidics, Royston, UK) droplet microfluidic device and the Illumina NextSeq550 system (Illumina, San Diego, CA). Data alignment was performed using STAR v2.4.0, and further analysis was performed using the Seurat, singleR, and clusterProfiler packages in R (R Foundation for Statistical Computing, Vienna, Austria). RESULTS: hDPSCs and hPDLSCs were separated into 3 clusters. hDPSCs mainly exhibited osteogenic and neurogenic cell populations. The main populations of hPDLSCs comprised osteogenic and myofibroblastic populations. hPDLSCs showed high "scores" for osteogenic gene expression, whereas hDPSCs had high neurogenic and endogenic scores. CONCLUSIONS: Single-cell RNA sequencing of hDPSCs and hPDLSCs revealed that the genes were expressed in specific clusters. The results of these analyses can be used as reference databases and valuable resources for further research in dental therapeutics.

MAPS-seq: magnetic bead-assisted parallel single-cell gene expression profiling.

Recently developed single-cell RNA sequencing methods allow the simultaneous profiling of the transcriptomes of thousands of individual cells. However, current methods still require advanced equipment or entail substantial waste of reagents. Here, we introduce magnetic bead-assisted parallel single-cell gene expression sequencing (MAPS-seq), a microwell-based method that pools samples before the reverse transcription step, increasing the ease of sample preparation and reducing reagent waste. Moreover, because this method uses universal reagents and standard molecular biology lab instruments, it is easy to implement, even in labs that have not previously conducted single-cell RNA sequencing. We validated our method by demonstrating that it can generate gene expression data at the single-cell level. We then applied the MAPS-seq method to analyze 237 human myelogenous leukemia cells treated with one of three different drugs or dimethyl sulfoxide. We observed transcriptional changes and identified marker genes that indicate a drug response. Furthermore, the MAPS-seq method produced data of comparable quality to those of existing single-cell RNA sequencing methods. Consequently, we expect that our method will provide researchers with a more accessible, less wasteful, and less burdensome method for investigating the transcriptomes of individual cells.

Neural regulation of energy and bone homeostasis by the synaptic adhesion molecule Calsyntenin-3.

Neuronal regulation of energy and bone metabolism is important for body homeostasis. Many studies have emphasized the importance of synaptic adhesion molecules in the formation of synapses, but their roles in physiology still await further characterization. Here, we found that the synaptic adhesion molecule Calsyntenin-3 (CLSTN3) regulates energy and bone homeostasis. Clstn3 global knockout mice show reduced body mass with improved leptin sensitivity and increased energy expenditure compared to their wild-type littermates. In addition, Clstn3 knockout mice show reduced marrow volume and cortical bone mass without alteration of trabecular bone microarchitecture. This reduced bone mass is not bone cell-autonomous because neither osteoblast- nor osteoclast-specific Clstn3 knockout mice show bone defects; similarly, in vitro cultures of both Clstn3 knockout osteoblasts and osteoclasts do not show any defects. These reduced body and bone mass phenotypes can be attributed instead to neuronal CLSTN3 because they are recapitulated by pan-neuronal but not sympathetic neuron-specific deletion of Clstn3. This study reveals novel physiological functions of neuronal Clstn3 as a key regulator of energy and bone homeostasis.

Do anatomic variations of the middle turbinate have an effect on nasal septal deviation or paranasal sinusitis?

OBJECTIVES: We evaluated the relationship between 1) anatomic variations of the middle turbinate and bony septal deviations and 2) chronic sinusitis. METHODS: We compared 73 computed tomographic scans of healthy control patients with 461 scans performed for evaluation of nasal symptoms. Paranasal sinusitis was identified. We recorded the incidences of anatomic variation of the middle turbinate and of bony septal deviation. RESULTS: The incidences of anatomic variation of the middle turbinate and of bony septal deviation were not significantly different between the control group and the symptomatic group. Anatomic variation of the middle turbinate was related to contralateral septal deviation. There was no statistical relationship between bony septal deviation or middle turbinate variation and sinusitis. CONCLUSIONS: Anatomic variations of the middle turbinate have an effect on bony septal deviations to the contralateral side. However, middle turbinate variations and bony septal deviation are not associated with chronic sinusitis.

Short-term changes of hearing and distortion product otoacoustic emissions in sudden sensorineural hearing loss.

OBJECTIVES: The function of outer hair cells can be measured objectively and noninvasively by distortion product otoacoustic emission (DPOAE). The aims of the study were to investigate the changes of DPOAE in the recovery course and to pursue the relationship between the changes of DPOAE and hearing improvement in patients with sudden sensorineural hearing loss. STUDY DESIGN: : Retrospective case series review. METHODS: Both DPOAE and pure tone audiometry were performed before 7 days after the onset and followed after 2 weeks in 40 patients with sudden sensorineural hearing loss. Patients were grouped on the basis of the initial hearing loss and the results of their recovery. All DPOAE amplitudes were analyzed at 2f1-f2, and DPOAE sum was calculated. RESULTS: The initial DPOAE sum in ears with the initial mild-to-moderate hearing loss (hearing threshold, 55 dB) compared with that in contralateral normal ears. In ears with the initial moderately severe to profound hearing loss, the changes of DPOAE sum values positively correlated with the hearing improvement but not in ears with the initial mild-to-moderate hearing loss. Although the presence of initial DPOAE responses indicated good prognosis, the absence of initial DPOAE responses did not always indicate poor prognosis. CONCLUSION: Our findings showed that the function of outer hair cells is relatively spared in ears with the initial mild-to-moderate hearing loss, and its recovery is not related to the hearing improvement; however, the function of outer hair cells is impaired in ears with the initial moderately severe to profound hearing loss, and the functional improvement of outer hair cells is important for hearing recovery. Clinical implications of our findings were discussed.

Test-retest reliability of vibration-induced nystagmus in peripheral dizzy patients.

The purpose of this study was to analyze test-retest reliability of vibration-induced nystagmus (VIN) in dizzy patients. Fifty-two consecutive patients with positive eye movements induced by vibration at all four different stimulation sites were enrolled. Evaluation of VIN was repeated in 2 separate sessions, 30 minutes apart. Maximum slow-phase eye velocities at different sites from the first and second sessions were assessed via the intraclass correlation coefficient (ICC) and the Pearson correlation coefficient. The incidence of directional changing of evoked nystagmus and the abnormal rates were also evaluated. Excellent reliability with ICC values ranging from 0.89-0.98 and substantial-to-excellent correlation was obtained for the maximum slow-phase eye velocities at different sites. The incidence of directional changes of evoked nystagmus was 0%-4% at each stimulation site. Forty-three patients (83%) had abnormal results in the first session and 41 patients (79%) had abnormal results in the second session. Overall, the direction and maximum slow-phase eye velocities of VIN for different stimulation sites had excellent test-retest reliability. The VIN test is a reliable test for detecting vestibular imbalance in evaluating a dizzy patient.

Effects of dietary iron levels on growth performance, hematological status, liver mineral concentration, fecal microflora, and diarrhea incidence in weanling pigs.

An experiment was conducted in weanling pigs (Landrace x Yorkshire x Duroc) to evaluate the effects of dietary iron levels on growth performance, hematological status, liver mineral concentration, fecal microflora, and diarrhea incidence. One hundred and forty-four piglets (initial BW 5.96 +/- 0.93 kg) were randomly allotted to one of the four dietary treatments on the basis of their body weights. The basal diets for each phase (phase 1: days 0 to 14; phase 2: days 15 to 28) were formulated to contain minimal Fe and then supplemented with gradient levels of Fe (0, 50, 100, and 250 mg/kg) from ferrous sulfate. Feces were collected on days 14 and 28 and used for the analysis of microbial count and trace minerals. Eight piglets from each treatment (two piglets per pen) were bled at 0, 7, 14, 21, and 28 days to determine their hematological and plasma Fe status. In addition, two piglets from each pen (eight piglets per treatment) were killed at days 14 and 28 to determine liver mineral concentrations. Pigs fed supplemental 250 ppm Fe showed lowest overall average daily gain (linear, p = 0.036). Diarrhea incidence was linearly increased (p < 0.001) with supplemental Fe level. On days 14, coliform population in normal feces was increased (p = 0.036) linearly with supplemental Fe level, and there were higher (p = 0.043) coliform population and lower (p < 0.001) Bifidobacterium spp. in the diarrhea feces. Supplemental Fe linearly (p < 0.05) improved the total red blood cells, hemoglobin, plasma, and liver (p = 0.109) Fe status of pigs and also increased (linear and quadratic, p < 0.001) the fecal excretion of Fe on days 14 and 28. It is concluded that increasing the dietary iron levels in piglets improved their hematological status and liver Fe content; however, higher dietary Fe levels might also be associated with the increased diarrhea incidence.