Human ; Endocrinology

BACKGROUND: Heavy metals are significant risk factors for kidney function. Numerous studies have shown that exposure to heavy metals negatively correlates with kidney function through oxidative stress pathways, and serum α-klotho is linked to oxidative stress. However, the role of α-klotho in the relationship between blood lead, mercury, and kidney function remains unclear. METHOD: This study evaluated the mediating role of alpha-klotho in the relationship between lead, mercury and renal function, using data from the 2007-2016 National Health and Nutrition Examination Survey (NHANES) in U.S. adults aged 40-79. The sample included 11,032 participants, with blood lead, mercury, α-klotho, and other relevant covariates measured. Inductively coupled plasma mass spectrometry was used to assess blood lead and mercury levels, and enzyme-linked immunosorbent assay (ELISA) was employed to measure serum α-klotho. Kidney function was evaluated using estimated glomerular filtration rate (eGFR) based on creatinine levels. Multivariable linear regression was conducted to analyze the relationships between blood lead, mercury, α-klotho, and eGFR. A mediation analysis model was used to assess whether α-klotho influenced these associations. RESULTS: We observed a significant association between blood lead and eGFR. Mediation analysis revealed that α-klotho accounted for 12.76% of the relationship between serum lead and eGFR in the NHANES population. Subgroup analysis showed that α-klotho mediated 12.43%, 6.87%, 21.50% and 5.44% of the relationship between blood lead and eGFR in women, middle-aged adults (40-59 years old), without cardiovascular disease and hypertension, respectively. However, α-klotho did not mediate the relationship between blood mercury and eGFR in terms of gender or age. This newly identified pathway may provide valuable insights for the prevention and treatment mechanisms related to kidney function impairment. CONCLUSION We found that blood lead was associated with renal function. According to the results of subgroup analysis, for blood lead, serum α-klotho mediated the association in females, middle aged 60-79 years. The relationship between blood mercury and renal function was not clinically significant, and serum α-Klotho mediated the relationship between blood mercury and renal function without significant clinical significance.
Humans ; Middle Aged ; Lead/blood* ; Female ; Klotho Proteins ; Male ; Aged ; Adult ; Mercury/blood* ; Glomerular Filtration Rate ; Nutrition Surveys ; United States ; Kidney/physiology* ; Glucuronidase/blood* ; Environmental Pollutants/blood*

BACKGROUND: SARS-CoV-2 (COVID-19) is transmitted via infectious respiratory particles. Infectious respiratory particles are released when an infected person breathes, coughs, or speaks. Several studies have measured respiratory particle concentrations through focusing on activities such as breathing, coughing, and short speech. However, few studies have investigated the effect of speech duration. METHODS: This study aimed to clarify the effects of speech duration and volume on the respiratory particle concentration. Study participants were requested to speak at three voice volumes across five speech durations, generating 15 speech patterns. Participants spoke inside a clean booth where particle concentrations and voice volumes were measured and analyzed during speech. RESULTS: Our findings suggest that as speech duration increased, the aerosol number concentration also increased. Through focusing on individual differences, we considered there might be super-emitters who emit more aerosol particles than the average human. Two participants were identified as statistical outliers (aerosol number concentration, n = 1; mass concentration, n = 1). CONCLUSIONS Considering speech duration may improve our understanding of respiratory particle concentration dynamics. Two participants were identified as potential super-emitters.
Humans ; Male ; Speech/physiology* ; Adult ; Female ; COVID-19/transmission* ; Respiratory Aerosols and Droplets ; Voice ; SARS-CoV-2 ; Time Factors ; Young Adult ; Aerosols/analysis*

BACKGROUND: Low-density lipoprotein cholesterol (LDLc) is regarded as a risk factor for endothelial dysfunction. However, LDLc stimulates the proliferation of hematopoietic stem cells (CD34-positive cells), which contribute to endothelial repair. Therefore, LDLc may have a beneficial influence on the endothelium of individuals with lower endothelial repair activity. METHODS: This cross-sectional study included 245 men aged 60-69 years. Endothelial repair activity was categorized by the circulating levels of CD34-positive cells based on median values. The status of endothelium was evaluated using the cardio-ankle vascular index (CAVI). RESULTS: Among individuals with low levels of circulating CD34-positive cells, LDL-c levels were significantly inversely correlated with CAVI and positively correlated with circulating CD34-positive cells. No significant correlations were observed among the participants with high levels of circulating CD34-positive cells. Among low levels of CD34-positive cells, the adjusted standardized parameter (β) and p value were -0.24 (p = 0.021) for CAVI and 0.41 (p < 0.001) for CD34-positive cells, whereas among high levels of CD34-positive cells, the corresponding values were 0.03 (p = 0.738) and -0.09 (p = 0.355). CONCLUSION LDLc has a beneficial influence on endothelial health among individuals with low endothelial repair activity, possibly by stimulating the proliferation of hematopoietic stem cells.
Humans ; Middle Aged ; Male ; Aged ; Cross-Sectional Studies ; Cholesterol, LDL/blood* ; Endothelium, Vascular/physiology* ; Antigens, CD34/blood* ; Hematopoietic Stem Cells

BACKGROUND: Neck cooling is a practical method for preventing heat-related illness, however, its effectiveness in general workers is not well established. This study aimed to assess the effects of neck cooling on core body temperature and other physiological markers during exercise in a hot environment. METHODS: This randomized crossover trial was conducted from November 2023 to April 2024 at the Shared-Use Research Center at UOEH. Fourteen healthy adult males participated in the study under two conditions: with neck cooling (COOL) and without neck cooling (CON). All participants completed both conditions, and the order of condition assignment was determined by a random draw. Participants first rested for 10 minutes in a 28.0 °C, 50% relative humidity environment, followed by a rest in a 35.0 °C, 50% relative humidity environment for another 10 minutes. In the COOL condition, participants wore a neck cooler containing 1,200 g of ice while exercising at 50% Heart Rate Reserve on a bicycle ergometer for 20 minutes. Afterward, they rested for 15 minutes in the hot environment while still wearing the cooler. MAIN OUTCOME MEASURES: Core body temperature (rectal and esophageal), forehead skin temperature, and heart rate were continuously monitored and compared using a mixed model. Estimated sweat volume was calculated based on changes in body weight before and after the experiment. RESULTS: At the end of the rest period, no significant differences were observed between the COOL and CON conditions in rectal temperature (37.76 ± 0.18 °C versus 37.75 ± 0.24 °C, p = 0.9493), esophageal temperature (37.75 ± 0.30 °C versus 37.76 ± 0.23 °C, p = 0.7325), forehead skin temperature (36.87 ± 0.29 °C versus 36.88 ± 0.27 °C, p = 0.2160), or heart rate (104.18 ± 7.56 bpm versus 107.52 ± 7.40 bpm, p = 0.1035). Estimated sweat loss was similar between conditions (578 ± 175 g for CON versus 572 ± 242 g for COOL, p = 0.5066). While more participants felt cooler in the COOL condition, RPE showed no significant difference. CONCLUSION Neck cooling did not significantly affect core temperature or perceived exertion. Maintaining close contact with the skin at sufficiently low temperatures or utilizing cooling methods that prevent excessive negative feedback may be necessary to enhance the effectiveness of neck cooling.
Humans ; Male ; Cross-Over Studies ; Exercise/physiology* ; Adult ; Neck/physiology* ; Hot Temperature/adverse effects* ; Young Adult ; Body Temperature ; Heart Rate ; Skin Temperature ; Body Temperature Regulation ; Cold Temperature

BACKGROUND: Difficulty in chewing has been shown to be associated with increased mortality, geriatric syndromes, and poor activities of daily living, indicating the need for intervention. Chewing difficulties are related to tooth loss, periodontitis, dry mouth, and a number of oral health conditions. Diabetes mellitus (DM) is one of the major causes of global burden of diseases, and has been associated with poor oral health. Prospective association between oral health status and the development of diabetes has also been reported. However, relationship between glycemic control and self-reported chewing difficulty remains less explored in working-age populations. The objective of this study is to cross-sectionally explore the association between fasting blood glucose (FBG) and self-reported chewing difficulty in adults working in a Japanese worksite. METHODS: Participants from the Aichi Workers' Cohort Study who responded to the 2018 survey were included. Participants were categorized into five FBG groups (<100, 100-109, 110-125, 126-159, and ≥160 mg/dl). Multivariable odds ratios (ORs) and 95% confidence intervals (CIs) for chewing difficulty were estimated using logistic regression adjusted for age, sex, body mass index, smoking and alcohol consumption status, number of teeth, presence of periodontal disease and the number of anti-diabetic medication classes. RESULTS: A total of 164 participants (4.2%) reported difficulty with chewing, the prevalence of which tended to increase with increasing FBG level. FBG ≥160 mg/dl was significantly and strongly associated with difficulty with chewing in the final multivariable model (multivariable OR 3.84 [95% CI 1.13-13.0]). CONCLUSIONS A relationship between higher FBG levels and difficulty with chewing was observed, independent of potential confounding factors. However, prospective or interventional studies are needed to determine causality.
Humans ; Male ; Japan/epidemiology* ; Female ; Mastication/physiology* ; Middle Aged ; Adult ; Blood Glucose/analysis* ; Cross-Sectional Studies ; Fasting/blood* ; Cohort Studies ; Oral Health ; Prevalence

OBJECTIVE: To explore the changes of CKLF-like MARVEL transmembrane domain-containing 6 (CMTM6) and programmed death-ligand 1 (PD-L1) expression in gastric mucosal epithelial cells after Helicobacter pylori infection and the regulation of CMTM6 on PD-L1, and to analyze the mRNA expression differences before and after CMTM6 gene knock-out in helicobacter pylori infected gastric epithelial cells by microarray analysis. METHODS: The standard Helicobacter pylori strain ATCC 26695 was co-cultured with human gastric epithelial cell GES-1 for 6, 24 and 48 hours, and the mRNA and protein levels of CMTM6 and PD-L1 were detected by real-time quantitative PCR and Western blot. Using CRISPR/Cas9 to construct CMTM6 gene knockout plasmid and knockout CMTM6 gene of GES-1 cells. Helicobacter pylori was co-cultured with CMTM6 gene knockout and wild type GES-1 cells for 48 hours to detect PD-L1 transcription and protein level changes, and CMTM6 gene knockout GES-1 cells were treated with the proteasome inhibitor MG-132 to detect the changes in PD-L1 protein levels. Agilent Human ceRNA Microarray 2019 was used to detect the differentially expressed genes in CMTM6 gene knockout and wild-type GES-1 cells co-cultured with Hp for 48 hours, and the signal pathway of differentially expressed genes enrichment was analyzed by Kyoto Encyclopedia of Genes and Genomes (KEGG) database. RESULTS: The mRNA and protein levels of CMTM6 and PD-L1 in GES-1 cells were significantly up-regulated after Helicobacter pylori infection, and CMTM6 mRNA was most significantly up-regulated 48 hours after infection. After CMTM6 gene knockout, the CD274 gene transcription level of Helicobacter pylori infected GES-1 cells did not change significantly, but PD-L1 protein level was significantly down-regulated, and the PD-L1 level increased after the application of proteasome inhibitor MG-132. After CMTM6 gene knockout, 67 genes had more than two times of differential expression. The transcription levels of TMEM68, FERMT3, GPR142, ATP6V1FNB, NOV, UBE2S and other genes were significantly down-regulated. The transcription levels of PCDHGA6, CAMKMT, PDIA2, NTRK3, SPOCK1 and other genes were significantly up-regulated. After CMTM6 gene knockout, ubiquitin-conjugating enzyme E2S (UBE2S) gene expression was significantly down-regulated, which might affect protein ubiquitination degradation. After CMTM6 gene knockout, adrenoceptor alpha 1B (ADRA1B), cholinergic receptor muscarinic 1 (M1), CHRM1, platelet activating factor receptor (PTAFR) gene expression was significantly up-regulated. CONCLUSION Helicobacter pylori infection up-regulates the expression level of CMTM6 in gastric mucosa cells, and CMTM6 can stabilize PD-L1 and maintain the protein level of PD-L1. CMTM6 gene knockout may affect biological behaviors such as protein ubiquitination and cell surface receptor expression.
Humans ; MARVEL Domain-Containing Proteins/metabolism* ; Helicobacter pylori/physiology* ; B7-H1 Antigen/genetics* ; Helicobacter Infections/metabolism* ; Epithelial Cells/metabolism* ; Gastric Mucosa/metabolism* ; Chemokines/metabolism* ; Cell Line ; Gene Knockout Techniques ; Myelin Proteins

OBJECTIVE: To assess the osteogenesis height in maxillary sinus segment one year after zygomatic implantation by imaging methods, and evaluate the influence of patient factors, maxillary sinus anatomical factors and surgical factors on postoperative osteogenesis height. METHODS: This study is a retrospective study, including patients who underwent zygomatic implantation and whose zygomatic implants passed through the maxillary sinus at the Department of Implantology, Peking University School and Hospital of Stomatology from July 2017 to January 2022. Preoperative and postoperative cone beam CT (CBCT)was taken to measure and calculate the average osteogenesis height (AOH) in maxillary sinus segment of the zygomatic implants, then the residual bone height, the width and morphology of the maxillary sinus floor in the buccal and palatal directions were measured. Besides, the integrity of Schneiderian membrane during implant surgery, and the general information of the patients and zygomatic implants were recorded. By comparing anatomical situations and surgical characteristics, the differences of AOH under different conditions were analyzed. Then AOH was divided into two groups (obvious osteogenesis group and non-obvious osteogenesis group) using the median as the threshold, and the influencing factors of osteogenesis were evaluated using mixed effect generalized linear model univariable and multivariable analysis. RESULTS: A total of 47 zygomatic implants were implanted in 24 patients. During the average follow-up period of 12.1 months, there was no implant failure, and the implant survival rate was 100%. Postoperative CBCT showed that 43 zygomatic implants had osteogenic images in the maxillary sinus segment, most of which originated from the floor of the maxillary sinus, and the median AOH was 3.1 mm [interquartile range (IQR): 4.0 mm]. In terms of maxillary sinus width, there were 31 cases (66.0%) of wide type and 16 cases (34.0%) of narrow type. In the aspect of buccal and palatal morphology, 17 cases were taper (36.2%), 20 cases were round (42.6%), and 10 cases were flat (21.3%). The median of residual bone height was 2.8 mm (IQR: 2.2 mm) before operation. Univa-riate analysis of mixed effect generalized linear model showed that postoperative obvious osteogenic rate was related to the residual bone height (OR=2.09, P=0.006). Multivariate analysis showed that the resi-dual bone height (OR=2.55, P=0.022) and the shape of a taper maxillary sinus (OR=11.44, P=0.040) had a significant impact on the postoperative obvious osteogenic rate. CONCLUSION The maxillary sinus floor showed osteogenic images 1 year after the zygomatic implantation surgery. Larger residual bone height and the shape of a taper maxillary sinus may be favorable factors for osteogenesis.
Humans ; Maxillary Sinus/surgery* ; Cone-Beam Computed Tomography ; Retrospective Studies ; Zygoma/diagnostic imaging* ; Male ; Female ; Osteogenesis/physiology* ; Middle Aged ; Adult ; Dental Implants ; Aged ; Dental Implantation, Endosseous/methods*

OBJECTIVE: To investigate the changes and symmetry of facial soft tissue during posed smile, to analyze the feature of posed smile in different gender, and verify the reproducibility of posed smile. METHODS: Three-dimensional (3D) facial images of 41 adults (16 males and 25 females with an average age of 26.76±2.70 years) which were taken by FaceScan three-dimensional sensor, including one rest position and two posed smile images. Then these images were imported into 3D soft tissue analysis software for model repositioning. 3D morphable model method (3DMM) was carried out to automatic landmarks setting. After that, the measurement of the eyes, cheeks, nose and perioral area were carried out for 3D soft tissue analysis. Finally, the changes and symmetry of the soft tissues between the two expression states and the gender differences during the posed smiles were compared. Meanwhile, the reproducibility of posed smile was statistically tested. RESULTS: Compared with the rest position, except for nasolabial angle (1.45°±7.65°), the measurements of 3D soft tissue in other region were changed in posed smile (P < 0.001). It should be noted that the eye region was also significantly changed (P < 0.001). Furthermore, the prominent feature of posed smile was that the alar base length became longer, the upper and lower vermilions were narrow and thin, and the mentolabial furrows became shallow. Meanwhile the chin extended anteriorly while the mouth retracted; During posed smile, the labial fissure asymmetry [2.78 (1.73, 3.49) mm], mid-infraorbital asymmetry [2.36 (1.22, 3.27) mm] and outercanthal asymmetry [2.31(1.29, 2.80) mm] were most apparent. Compared with the rest position, the asymmetry was not significantly increased except for cheilion and alar curvature points during the posed smile (P>0.05). In the posed smile, the changes of the right palpebral fissure height and the thickness of lower vermilion (|Li-Stoi| _z) of males were greater than those of females (P < 0.05), and asymmetry of exocanthion and cheekbone increased more than that of females (P < 0.05). There was no obvious difference between the two posed smiles. CONCLUSION In this study, during the posed smile the soft tissues of the eyes, cheeks, nose, lips and chin changed in different degrees, and the asymmetry of cheilion and alar curvature point was greater than that of the rest position; In addition, the reproducibility of posed smile was excellent, which can be a reference for clinical aesthetics and functional research of smile.
Humans ; Smiling/physiology* ; Female ; Male ; Adult ; Imaging, Three-Dimensional/methods* ; Face/anatomy & histology* ; Young Adult ; Facial Expression

OBJECTIVE: To study hesperetin-induced vasorelaxation after depolarizing contraction in human umbilical veins (HUVs) to elucidate the role of L-type Ca²⁺ channel (LTCC) and related signaling pathway. METHODS: Isometric tension recording was performed in HUV rings pre-contracted with K⁺. Hesperetin relaxing mechanism was investigated using a LTCC opener (BayK8644) and blockers of cyclic nucleotides and phosphodiesterases (PDEs). Whole-cell patch-clamping in A7r5 cells, a rat vascular smooth muscle cell line, was performed to study the effect of hesperetin on LTCC current. RESULTS: After depolarizing precontraction, hesperetin induced HUV relaxation concentration-dependently and endothelium-independently; 1 mmol/L hesperetin reduced denuded HUV ring tension by 68.7% ± 4.3% compared to matching vehicle, osmolality, and time controls (P<0.0001). Importantly, hesperetin competitively inhibited BayK8644-induced contraction, shifting the half maximal effective concentration of BayK8644 response from 1.08 nmol/L [95% confidence interval (CI) 0.49-2.40] in vehicle control to 11.30 nmol/L (95% CI 5.45-23.41) in hesperetin (P=0.0001). Moreover, hesperetin elicited further vasorelaxation in denuded HUV rings pretreated with inhibitors of soluble guanylyl cyclase, adenylyl cyclase, PDE3, PDE4, and PDE5 (P<0.01), while rings pretreated with PDE1 inhibitors could not be relaxed by hesperetin (P>0.05). However, simultaneously applying inhibitors of soluble guanylyl cyclase and adenylyl cyclase could not inhibit hesperetin's effect (P>0.05). In whole-cell patch-clamping, hesperetin rapidly decreased LTCC current in A7r5 cells to 66.7% ± 5.8% (P=0.0104). CONCLUSIONS Hesperetin diminishes depolarizing contraction of human vascular smooth muscle through inhibition of LTCC, and not cyclic nucleotides nor PDEs. Our evidence supports direct LTCC interaction and provides additional basis for the use of hesperetin and its precursor hesperidin as vasodilators and may lead to future vasodilator drug development as a treatment alternative for cardiovascular diseases.
Hesperidin/pharmacology* ; Humans ; Calcium Channels, L-Type/metabolism* ; Umbilical Veins/physiology* ; Muscle Contraction/drug effects* ; Animals ; Rats ; Calcium Channel Blockers/pharmacology* ; Vasodilation/drug effects* ; Muscle Relaxation/drug effects*