Periodontitis promotes bacterial extracellular vesicle-induced neuroinflammation in the brain and trigeminal ganglion.

Gram-negative bacteria derived extracellular vesicles (EVs), also known as outer membrane vesicles, have attracted significant attention due to their pathogenic roles in various inflammatory diseases. We recently demonstrated that EVs secreted by the periodontopathogen Aggregatibacter actinomycetemcomitans (Aa) can cross the blood-brain barrier (BBB) and that their extracellular RNA cargo can promote the secretion of proinflammatory cytokines, such as IL-6 and TNF-α, in the brain. To gain more insight into the relationship between periodontal disease (PD) and neuroinflammatory diseases, we investigated the effect of Aa EVs in a mouse model of ligature-induced PD. When EVs were administered through intragingival injection or EV-soaked gel, proinflammatory cytokines were strongly induced in the brains of PD mice. The use of TLR (Toll-like receptor)-reporter cell lines and MyD88 knockout mice confirmed that the increased release of cytokines was triggered by Aa EVs via TLR4 and TLR8 signaling pathways and their downstream MyD88 pathway. Furthermore, the injection of EVs through the epidermis and gingiva resulted in the direct retrograde transfer of Aa EVs from axon terminals to the cell bodies of trigeminal ganglion (TG) neurons and the subsequent activation of TG neurons. We also found that the Aa EVs changed the action potential of TG neurons. These findings suggest that EVs derived from periodontopathogens such as Aa might be involved in pathogenic pathways for neuroinflammatory diseases, neuropathic pain, and other systemic inflammatory symptoms as a comorbidity of periodontitis.

Cardiovascular risk factors and quality of life among stroke survivors in Korea from 2013 to 2018: a cross-sectional cohort study.

BACKGROUND: Although the cardiovascular health and quality of life (QoL) of stroke survivors have been previously studied, no study has investigated the correlation between cardiovascular health and QoL. This study aimed to investigate whether there would be a difference in the quality of life (QoL) in this population depending on the degree of cardiovascular health. METHODS: Overall, 577 people aged > 40 years who participated in the Korea National Health and Nutrition Examination Survey from 2013 to 2018 were included and were divided into three groups according to the survey period (2013-2014, n = 145; 2015-2016, n = 198; and 2017-2018, n = 234). Participants were further divided into the following groups based on their cardiovascular health score, as defined by the American Heart Association: poor, intermediate, and ideal groups. We examined how the health-related QoL score was expressed through the five-dimensional European Quality of Life Questionnaire (EQ-5D-3L). RESULTS: The ideal (cardiovascular health scores 11-14) and intermediate (cardiovascular health scores 8-10) groups had the lowest (7.72-8.14%) and highest (46.39-57.70%) number of participants, respectively. The total EQ-5D index score was highest in the ideal group, followed by the intermediate and poor groups across all three periods (2013-2014, p = 0.0015; 2015-2016, p = 0.0040; 2017-2018, p < 0.0001). The dimension-specific analysis revealed that, Findings showed that stroke survivors' mobility significantly varied by cardiovascular health scores (p = 0.0371 in 2015-2016, p =0.0486 in 2017-2018), whereas usual activities (p = 0.0322) and pain/discomfort (p = 0.0420) were significantly different among the three groups in 2015-2016. CONCLUSION: QoL in post-stroke survivors, when related to cardiovascular health degree, could be correlated with stroke sequelae.

Changes in Intestinal Microbiota Due to the Expanded Polystyrene Diet of Mealworms (Tenebrio molitor).

Expanded polystyrene (EPS), which is difficult to decompose, is usually buried or incinerated, causing the natural environment to be contaminated with microplastics and environmental hormones. Digestion of EPS by mealworms has been identified as a possible biological solution to the problem of pollution, but the complete degradation mechanism of EPS is not yet known. Intestinal microorganisms play a significant role in the degradation of EPS by mealworms, and relatively few other EPS degradation microorganisms are currently known. This study observed significant differences in the intestinal microbiota of mealworms according to the dietary results of metagenomics analysis and biodiversity indices. We have proposed two new candidates of EPS-degrading bacteria, Cronobacter sakazakii and Lactococcus garvieae, which increased significantly in the EPS feeding group population. The population change and the new two bacteria will help us understand the biological mechanism of EPS degradation and develop practical EPS degradation methods.

Stigmatizing Beliefs About Depression in Diverse Ethnic Groups of Asian Americans.

Focusing on diverse ethnic groups of Asian Americans, the present study examined the prevalence, ethnic variations, and predictors of stigmatizing beliefs about depression (beliefs that associate depression with a sign of weakness, shame to the whole family, and family disappointment, and beliefs that antidepressant medicines are addictive). Data were drawn from 2609 participants (age range 18-98) in the 2015 Asian American Quality of Life survey that includes Chinese, Asian Indian, Korean, Vietnamese, Filipinos, and other Asians. Results of a series of logistic models indicated that age, gender, ethnicity, length of stay in the U.S., English proficiency, and acculturation were significantly associated with stigmatizing beliefs about depression. Ethnic variations in beliefs were also observed. Implications for research and practice are discussed.

Electrochemical Fragmentation of Cu2O Nanoparticles Enhancing Selective C-C Coupling from CO2 Reduction Reaction.

In this study, we demonstrate that the initial morphology of nanoparticles can be transformed into small fragmented nanoparticles, which were densely contacted to each other, during electrochemical CO2 reduction reaction (CO2RR). Cu-based nanoparticles were directly grown on a carbon support by using cysteamine immobilization agent, and the synthesized nanoparticle catalyst showed increasing activity during initial CO2RR, doubling Faradaic efficiency of C2H4 production from 27% to 57.3%. The increased C2H4 production activity was related to the morphological transformation over reaction time. Twenty nm cubic Cu2O crystalline particles gradually experienced in situ electrochemical fragmentation into 2-4 nm small particles under the negative potential, and the fragmentation was found to be initiated from the surface of the nanocrystal. Compared to Cu@CuO nanoparticle/C or bulk Cu foil, the fragmented Cu-based NP/C catalyst achieved enhanced C2+ production selectivity, accounting 87% of the total CO2RR products, and suppressed H2 production. In-situ X-ray absorption near edge structure studies showed metallic Cu0 state was observed under CO2RR, but the fragmented nanoparticles were more readily reoxidized at open circuit potential inside of the electrolyte, allowing labile Cu states. The unique morphology, small nanoparticles stacked upon on another, is proposed to promote C-C coupling reaction selectivity from CO2RR by suppressing HER.

Is neighborhood poverty harmful to every child? Neighborhood poverty, family poverty, and behavioral problems among young children.

This longitudinal study investigates the association between neighborhood poverty and behavioral problems among young children. This study also examines whether social environments mediate the relationship between neighborhood poverty and behavioral problems. We used data from the third and fourth waves of the Fragile Families and Child Wellbeing study to assess behavioral problems separately for children who experienced no family poverty, moved out of family poverty, moved into family poverty, and experienced long-term family poverty. Regression models assessed the effect of neighborhood poverty on behavioral problem outcomes among children aged 5 years, after controlling for sociodemographic characteristics and earlier behavioral problems. Results showed an association between neighborhood poverty and lower social cohesion and safety, which lead to greater externalizing problems among children with long-term family poverty living in high-poverty neighborhoods compared with those in low-poverty neighborhoods. Policies and community resources need to be allocated to improve neighborhood social environments, particularly for poor children in high-poverty neighborhoods.

Moderating Effects of Community Social Capital on Depression in Later Years of Life: A Latent Interaction Model.

OBJECTIVE: This study tested the stress-buffering model and examined the buffering role of community social capital on late-life depression. METHODS: This study used the data from the second wave of National Social Life, Health, and Aging Project (NSHAP, 2010-2012). In the present study, a total of 2,362 older adults aged 65 and older (Mage = 74.5, SD = 6.69) were included. Latent moderated structural equations model was tested by comparing the main effect model and interaction model. Depression, stress, and community social capital were constructed as latent variables for the analyses. RESULTS: The main effect model was acceptable: χ2 (df = 334) = 1596.4, p = .000; RMSEA = .04 (.038 - .042); CFI = .91; and SRMR = .05. And interaction model was significant (D = 35.0, p < .001). The latent constructs of stress (ß = . 50, p < .001) and community social capital (ß = -.14, p < .001) not only had a direct effect on depression, but their interaction was also significant (ß = -.21, p < .01).). The group with a high level of social capital presented a relatively stable slope in the prediction of stress on depression, suggesting their resilience, while the group with a low level of community social capital demonstrated a steep slope, indicating heighten vulnerability to depression when faced with stress. CONCLUSIONS: The findings support the hypothesis of stress buffering model and identify the protective effects of community social capital on depression of older adults. CLINICAL IMPLICATIONS: Older adults with lower community social capital are particularly vulnerable to depression. The results highlight that practitioners and policymakers should pay more attention to finding ways to enhance community resources to improve older adults' mental health.

Mixed Copper States in Anodized Cu Electrocatalyst for Stable and Selective Ethylene Production from CO2 Reduction.

Oxygen-Cu (O-Cu) combination catalysts have recently achieved highly improved selectivity for ethylene production from the electrochemical CO2 reduction reaction (CO2RR). In this study, we developed anodized copper (AN-Cu) Cu(OH)2 catalysts by a simple electrochemical synthesis method and achieved ∼40% Faradaic efficiency for ethylene production, and high stability over 40 h. Notably, the initial reduction conditions applied to AN-Cu were critical to achieving selective and stable ethylene production activity from the CO2RR, as the initial reduction condition affects the structures and chemical states, crucial for highly selective and stable ethylene production over methane. A highly negative reduction potential produced a catalyst maintaining long-term stability for the selective production of ethylene over methane, and a small amount of Cu(OH)2 was still observed on the catalyst surface. Meanwhile, when a mild reduction condition was applied to the AN-Cu, the Cu(OH)2 crystal structure and mixed states disappeared on the catalyst, becoming more favorable to methane production after few hours. These results show the selectivity of ethylene to methane in O-Cu combination catalysts is influenced by the electrochemical reduction environment related to the mixed valences. This will provide new strategies to improve durability of O-Cu combination catalysts for C-C coupling products from electrochemical CO2 conversion.

A New Scoring System for the Differential Diagnosis between Tuberculous Meningitis and Viral Meningitis.

BACKGROUND: Tuberculous meningitis (TBM) is associated with high mortality and morbidity despite administering anti-tuberculous chemotherapy to the patients. Differential diagnosis between TBM and viral meningitis (VM) is difficult in some clinical situations. METHODS: We reviewed and analyzed records of adult patients who were admitted and diagnosed with TBM or VM at a tertiary hospital in Korea, between January 2006 and December 2015. Diagnostic criteria for TBM were categorized into three groups: definite, probable, and possible TBM. The VM group included patients with no evidence of other meningitis who achieved complete recovery with only conservative treatments. Clinical, laboratory and radiological findings, as well as outcomes, were compared between the TBM and VM groups. RESULTS: Ninety-eight patients were enrolled. Among the study patients, 47 had TBM and 51 had VM. Based on univariate analysis and multivariate logistic regression, sodium < 135 mmol/L in serum (hyponatremia), lactate dehydrogenase > 70 (U/L) in cerebrospinal fluid (CSF), protein > 160 (mg/dL) in CSF, voiding difficulty, and symptoms of cranial nerve palsy were significant predictive factors for TBM in the final model. We constructed a weighted scoring system with predictive factors from multiple regression analyses. Receiver operating characteristic curve analyses and decision tree analyses were plotted to reveal an optimum cutoff point as 4 with this scoring system (range: 0-13). CONCLUSION: For differential diagnosis between TBM and VM, we created a new weighted scoring system. This scoring system and decision tree analysis are simple and easy to apply in clinical practice to differentiate TBM from VM.

Awareness and Acceptance of HIV Pre-exposure Prophylaxis among Medical Personnel and Men Who Have Sex with Men in Korea.

BACKGROUND: We aimed to investigate the awareness of human immunodeficiency virus (HIV) infection among high-risk individuals, including men who have sex with men (MSM) and medical personnel (MP) in Korea through a cross-sectional survey, identify possible obstacles hindering their access to pre-exposure prophylaxis (PrEP). METHODS: In 2016, the first questionnaire survey was sent to randomly selected MSM and MP. To compare the changes in attitudes and knowledge of MSM, a second questionnaire survey was conducted in August 2017. RESULTS: More than half of MSM (61.3% in 2016, 88.6% in 2017) were aware of PrEP. However, MP who offered PrEP had less knowledge regarding PrEP (23.4%). The background knowledge and experience with PrEP among MSM and MP in this survey was low (3.4% in 2016 and 5.7% in 2017, 1.9% in MP). The major obstacles that MSM reported were lack of insurance coverage (29% in 2016 and 32% in 2017), concern regarding adverse effects of PrEP (19% and 21%), and risk of exposing HIV-positive status to other people (15% and 18%). Among MP, lack of knowledge regarding the efficacy of PrEP was the most common obstacle (30%), followed by lack of insurance coverage (22%), and concern regarding adverse effects (20%). CONCLUSION: Our study showed that PrEP is required among MSM in Korea; however, most MP were not aware of PrEP. Lack of insurance coverage and knowledge regarding PrEP were major hindrances in the access to PrEP; therefore, further studies on how to make PrEP information more accessible are needed to help prevent HIV infection.

Enhanced Photocurrents with ZnS Passivated Cu(In,Ga)(Se,S)2 Photocathodes Synthesized Using a Nonvacuum Process for Solar Water Splitting.

Chalcopyrite Cu(In,Ga)(Se,S)2 (CIGS) semiconductors are potential candidates for use in photoelectrochemical (PEC) hydrogen generation due to their excellent optical absorption properties and high conduction band edge position. In the present research, CIGS thin film was successfully prepared on a transparent substrate (F:SnO2 glass) using a solution-based process and applied for a photocathode in solar water splitting, which shows control of the surface state associated with sulfurization/selenization process significantly influences on the PEC activity. A ZnS passivation surface layer was introduced, which effectively suppresses charge recombination by surface states of CIGS. The CIGS/ZnS/Pt photocathode exhibited highly enhanced PEC activity (∼24 mA·cm-2 at -0.3 V vs RHE). The performances of our CIGS photocathode on the transparent substrate were also characterized under front/back light illumination, and the incident photon to current conversion efficiency (IPCE) drastically changed depending on the illumination directions showing decreased IPCE especially under UV region with back illumination. The slow minority carrier (electron) transportation is suggested as a limiting factor for the PEC activity of the CIGS photocathode.

Variations in health-related quality of life (EQ-5D) associated with cardiovascular health: a cross-sectional study of adults with diabetes in the Korean general population.

OBJECTIVES: Previous studies on the differences in the mechanism and complications of diabetes between men and women have indicated potential sex differences in cardiovascular health, which affect health-related quality of life (HRQoL). DESIGN: A cross-sectional cohort study. SETTING: To determine how sex differences can be noticed, acknowledged and applied in clinical practice, we aimed to determine the cardiovascular (CV) health status of men and women with diabetes and its effects on HRQoL. PARTICIPANTS: In total, 2829 individuals with diabetes (1518 men and 1311 women) aged ≥40 years who participated in the Korean National Health and Nutrition Examination Survey from 2013 to 2018 were enrolled. OUTCOME MEASURES: Individuals with diabetes were categorised into poor, intermediate and ideal groups based on CV health indicators recommended by the American Heart Association. We used EQ-5D-3L to compare HRQoL scores between the sexes. Multivariable ordinal logistic regression and analysis of covariance were used to analyse the outcome variables. RESULTS: In the poor CV health score group, female sex was associated with mobility problems (OR 1.93, 95% CI 1.46 to 2.54), problems with usual activities (OR1.71, 95% CI 1.24 to 2.35), pain/discomfort (OR 1.69, 95% CI 1.32 to 2.16) and anxiety/depression (OR 1.66 95% CI 1.16 to 2.38). In the intermediate and ideal CV health score groups, female sex was associated with pain/discomfort (OR 1.57, 95% CI 1.15 to 2.15). Men had higher EQ-5D index scores in the poor and intermediate CV health score groups than did women. CONCLUSIONS: Although women tended to have high health-related CV health scores, HRQoL was lower in women than in men, especially in the poor CV health score group and in the pain/discomfort domain.

Sex differences in cardiovascular risk factors and quality of life among individuals with hypertension in Korea from 2013 to 2018: A cross-sectional cohort study.

As its prevalence increases and its association with cardiovascular disease and mortality is established, there is a need to improve prevention and management strategies for hypertension. Therefore, we aimed to compare differences in cardiovascular health status between men and women with hypertension defined by systolic blood pressure ≥140 mmHg and diastolic blood pressure ≥90 mmHg, and/or treatment with antihypertensive drugs. The association between cardiovascular health status and health-related quality of life was also evaluated. Additionally, a secondary analysis was performed on the cross-sectional data from 7306 adults with hypertension, ≥40 years of age between 2013 and 2018. Of this sample, 51.2% of patients were women from the Korean National Health and Nutrition Examination Survey. The seven Cardiovascular Health Metrics were used to quantify cardiovascular health status and the 5-dimensional European Quality of Life Questionnaire (EQ-5D) was used to evaluate health-related quality of life. A higher proportion of men than that of women was observed in the poor cardiovascular health score group [total score 0-7], with a higher proportion of women in the intermediate group [total score 8-10] and ideal group [total 11-14] (p<0.0001). The proportion of women in the EQ-5D index was higher than that of men in the poor and intermediate groups (p<0.0001), with no difference in the proportion of men and women in the ideal group (p = 0.1452). Furthermore, specific cardiovascular risk factors were different between men and women: women had lower physical activity level and higher prevalence of high cholesterol (≥200 mg/dl), and men had higher body mass indices and worse diet management. These findings indicate that prevention and management strategies for hypertension and cardiovascular health might need to differ for men and women to improve outcomes.

Mer tyrosine kinase regulates bone metabolism, and its deficiency partially ameliorates periodontitis- and ovariectomy-induced bone loss in mice.

Bone homeostasis is maintained by tightly coordinated activities of bone-forming osteoblasts and bone-resorbing osteoclasts. In the present report, the role of Mer tyrosine kinase (MerTK) in bone metabolism was investigated. The expression of MerTK decreased upon BMP2 stimulation of osteoblast precursors. The femurs of Mertk-deficient mice showed significantly increased bone volume with concomitant increase of bone formation and reduction in bone resorption. These bone phenotypes were attributed to the increased osteoblast differentiation and mineralization accounted by the enhanced ß-catenin and Smad signaling in the absence of MerTK in osteoblast precursors. Although the Mertk-deficient bone marrow macrophages were predisposed to enhanced osteoclast differentiation via augmented Ca2+-NFATc1 signaling, the dramatic increase of Tnfsf11b/Tnfsf11 (Opg/Rankl) ratio in Mertk knockout bones and osteoblast precursors corroborated the reduction of osteoclastogenesis in Mertk deficiency. In ligature-induced periodontitis and ovariectomy models, the bone resorption was significantly attenuated in Mertk-deficient mice compared with wild-type control. Taken together, these data indicate novel role of MerTK in bone metabolism and suggest a potential strategy targeting MerTK in treating bone-lytic diseases including periodontitis and osteoporosis.

Mental health status of individuals with diabetes in Korea before and during the COVID-19 pandemic: a comparison of data from the Korean national health and nutrition examination surveys of 2018-2019 and 2020-2021.

OBJECTIVES: This study aimed to compare the mental health status of patients with diabetes before and after the COVID-19 pandemic and to determine the effect of COVID-19 on their mental health status. This study was the first to investigate the relationship between diabetes and mental health in the Korean population during the COVID-19 pandemic. DESIGN: This retrospective cross-sectional study investigated the prevalence of mental health problems before (2018-2019) and during (2020-2021) the COVID-19 pandemic in individuals with diabetes aged 40 years or older who participated in the Korea National Health and Nutrition Examination Survey. Mental health problems were assessed using self-reported experiences of depression diagnosis, stress perception and suicide ideation. Depression was assessed using the Patient Health Questionnaire-9 (PHQ-9). Clinically significant depression requiring treatment was determined using an optimal cut-off score of 10 out of a total of 27 points. PARTICIPANTS: There were 824 men and 763 women in the 2018-2019 survey and 882 men and 887 women in 2020-2021. RESULTS: In the unadjusted analysis, women had a statistically significantly higher prevalence of suicide ideation in 2020-2021 (2.9, 95% CI: 1.5 to 4.2) than in 2018-2019 (1.0, 95% CI: 0.4 to 1.7, but p<0.0067). There was no statistically significant difference in both men and women in 2018-2019 after adjusting for age, education, economic activity, hypoglycaemic drug intake or insulin injection, current alcohol consumption, hypertension and hypercholesterolaemia. A comparison of the results of the PHQ-9 survey conducted in 2018-2019 and 2020-2021 found no statistically significant difference in the prevalence of depressive disorder among both men and women. CONCLUSIONS: Long-term, retrospective observations and studies on the effects of COVID-19 on the mental health of patients with diabetes should be conducted in the future.

Examining Predictors of Nicotine Dependence in Korean Adolescents : Comparing Ever Quitters and Never Quitters.

Despite growing research on adolescent smokers, evidence for the differences between the two smoker groups who are ever quitters and never quitters is limited. The study aimed to examine predictors of nicotine dependence (ND) in Korean adolescents by comparing ever quitters and never quitters. Data from 349 adolescents were collected through an online survey. Among respondents, most of them were male, living with families, and were enrolled at schools. Data were analyzed by dividing participants into two groups - ever quitters and never quitters. The study found that adolescents' ND was commonly predicted by smoking peers and anxiety. However, schooling status was significantly associated with ever quitters' ND only. In the total sample, never-quitters were associated with higher ND compared to ever-quitters. This study did not control for differences among ever quitters in terms of the number of attempts to quit smoking and did not significantly control age effects in the sample. Based on study results, we suggest various policy implications. Cessation intervention should be designed keeping in mind the smokers' previous quit attempts and their motivation. It is also recommended that individually tailored smoking cessation programs be used to address the heterogenous nature of the adolescents.

Efficacy of acupuncture on cardiovascular complications in patients with diabetes mellitus in Korea: A nationwide retrospective cohort.

OBJECTIVE: The main aim of this study is to investigate whether acupuncture could be an effective complementary treatment for reducing the risk of macrovascular complications in diabetic patients currently taking antidiabetic medications using a nationwide population-based database. METHODS: We conducted a retrospective cohort study to assess the efficacy of acupuncture on cardiovascular complications in diabetic patients using data from patients between 40 and 79 years of age, newly diagnosed with diabetes between 2003 and 2006, found in the National Health Insurance Service-National Sample Cohort (NHIS-NSC) in Korea. From the data, we identified 21,232 diabetic patients who were taking antidiabetic medication between 2003 and 2006. The selected patients were divided into two groups-those who received acupuncture at least three times and those who received no acupuncture (non-acupuncture) in the year following their diagnosis of diabetes. After 1:1 propensity score matching (PSM), each group had 3350 patients, and the observation ceased at the occurrence of a major adverse cardiovascular event (MACE), which was defined as either myocardial infarction, stroke, or death due to cardiovascular cause. RESULTS: After PSM, the acupuncture group had a lower incidence of MACE (hazard ratio [HR]: 0.87; 95% confidence interval [CI]: 0.81-0.94; P = 0.0003) and all-cause mortality (HR: 0.77; 95% CI: 0.70-0.84; P < 0.0001) than the non-acupuncture group; the HRs for stroke-related mortality (HR: 0.75; 95% CI: 0.56-1.00; P = 0.0485), ischemic heart disease mortality (HR: 0.53; 95% CI: 0.34-0.84; P = 0.006) and circulatory system disease mortality (HR: 0.67; 95% CI: 0.55-0.82; P < 0.0001) were lower in the acupuncture group than in the non-acupuncture group in the secondary analysis. CONCLUSION: Our results indicate that diabetic patients receiving acupuncture treatment might have a lower risk of MACE, all-cause mortality and cardiovascular mortality. This population-based retrospective study suggests beneficial effects of acupuncture in preventing macrovascular complications associated with diabetes. These findings call for further prospective cohort or experimental studies on acupuncture treatment for cardiovascular complications of diabetes. Please cite this article as: Jung H, Won T, Kim GY, Jang J, Yeo S, Lim S. Efficacy of acupuncture on cardiovascular complications in patients with diabetes mellitus in Korea: A nationwide retrospective cohort. J Integr Med. 2023; 21(2): 176-183.

Recent decline in atmospheric Pb deposition and isotopic constraints on changes in source contributions in snow from northwestern Greenland.

We present lead (Pb) concentrations and isotope ratios in a continuous series of 38 snow samples from a 1.9-m snow pit, covering the period from winter 2012 to summer 2017, at the East Greenland Ice-core Project (EGRIP) ice core drill site in northwestern Greenland. Pb concentrations were highly variable, ranging from 1.53 to 94.9 pg g-1 (mean value of 10.6 pg g-1), with higher concentrations during winter and spring and lower concentrations during summer and fall. Our results show a substantial reduction in the Pb concentration of ∼50% between the 2000s and 2010s, reaching a level close to that observed in the mid-18th century, that is, the time of the Industrial Revolution. Remarkably low radiogenic Pb isotope compositions were observed in our samples compared to previously reported values during the 2000s. The Pb isotope mixing model results indicated a decreasing Chinese contribution from the 2000s onwards, while Europe/Russia emerged as a relatively more important contributor to the anthropogenic Pb input to central Greenland during the corresponding period. Thus, we hypothesized that the reduction in Pb pollution in central Greenland is largely due to a decreasing contribution from Chinese sources in response to the effectiveness of stringent emission control measures in China.

Myeloid-Specific PTP1B Deficiency Attenuates Inflammation-Induced and Ovariectomy-Induced Bone Loss in Mice by Inhibiting Osteoclastogenesis.

The differentiation and activity of bone-resorbing osteoclasts are tightly regulated to maintain the homeostasis of healthy bones. In this study, the role of protein tyrosine phosphatase 1B (PTP1B) during osteoclastogenesis was studied in myeloid-specific Ptpn1-deficient (conditional knockout [cKO]) mice. The mRNA and protein expression of PTP1B increased during the formation of mature osteoclasts from mouse bone macrophages on stimulation with macrophage-colony stimulating factor (M-CSF) and receptor activator of nuclear factor κB ligand (RANKL). The Ptpn1 cKO mice exhibited increased femoral trabecular bone volume with a decreased number and activity of osteoclasts compared with control mice. The in vitro culture of osteoclast precursors corroborated the inhibition of osteoclastogenesis in cKO cells compared with control, with concomitantly decreased RANKL-dependent proliferation, lower osteoclast marker gene expression, reduced nuclear expression of nuclear factor of activated T cells cytoplasmic 1 (NFATc1), diminished intracellular Ca2+ oscillations, and increased phosphorylation of proto-oncogene tyrosine-protein kinase Src on inhibitory tyrosine residue. In a ligature-induced periodontitis model, Ptpn1 cKO mice exhibited attenuated osteoclastogenesis and alveolar bone loss following the induction of inflammation. The Ptpn1-deficient mice were similarly protected from ovariectomy-induced bone loss compared with control mice. These results provide a novel regulatory role of PTP1B in osteoclastogenesis and suggest a potential as a therapeutic target for bone-lytic diseases. © 2021 American Society for Bone and Mineral Research (ASBMR).

Inverted Tako-Tsubo cardiomyopathy associated with bronchoalveolar lavage.

Tako-Tsubo cardiomyopathy (TTC), also known as transient left ventricular (LV) ballooning syndrome or stress-induced cardiomyopathy, is characterised by transient LV dysfunction in the absence of significant angiographic coronary stenoses, frequently provoked by an episode of emotional or physical stress. In TTC, typically transient akinesis or dyskinesis of the LV apical segments with normal or hypercontractile basal wall motions is observed. Recently, several cases of atypical or inverted transient TTC sparing the LV apex have been reported. We report a case of inverted TTC showing akinesis of the basal and mid-ventricular segments of the LV with apical hyperkinesia triggered by bronchoscopy with bronchoalveolar lavage.