Association between serum α-Klotho levels and osteoarthritis prevalence among middle-aged and older adults: an analysis of the NHANES 2007-2016.

BACKGROUND: As individuals age, the prevalence of osteoarthritis tends to increase gradually. α-Klotho is a hormone renowned for its anti-aging properties. However, the precise role of serum α-Klotho in osteoarthritis is still not fully comprehended. METHODS: We conducted a cross-sectional study utilizing data from the National Health and Nutrition Examination Survey (NHANES) spanning from 2007 to 2016. Serum α-Klotho levels were measured using an enzyme-linked immunosorbent assay (ELISA). Osteoarthritis was assessed through self-reported questionnaires. Through univariate and multivariate logistic regression analyses, smooth curve fitting, threshold effect analysis, and subgroup analyses, we delved into the potential association between them. RESULTS: The study encompassed a cohort of 10,265 participants. In fully adjusted models of multivariate logistic regression analysis, we identified a negative correlation between serum ln α-Klotho and OA (OR = 0.77, 95% CI: 0.65-0.91, p = 0.003). When stratifying serum α-Klotho levels into tertiles, individuals in the highest tertile exhibited a 26% reduced risk of OA compared to those in the lowest tertile (OR = 0.84, 95% CI: 0.73-0.97, p = 0.014). Subsequent analyses indicated a linearly negative association. In subgroup analyses, we explored the relationship between serum ln α-Klotho and osteoarthritis across diverse populations, revealing the persistence of this association in the majority of subgroups. CONCLUSION: Serum α-Klotho levels exhibit a significant negative linear correlation with the prevalence of osteoarthritis in middle-aged and elderly populations in the United States.

Sand Burial, Rather than Salinity or Drought, Is the Main Stress That Limits the Germination Ability of Sophora alopecuroides L. Seed in the Desert Steppe of Yanchi, Ningxia, China.

Global change and environmental pollution have reawakened ecologists to the great threat of multi-stress interactions to different growth stages of plants. Sophora alopecuroides L., a dune plant, has been widely studied for its medicinal components and strong salinity tolerance. S. alopecuroides seeds, obtained from the desert steppe of Yanchi, Ningxia, China, were used to analyze the effects of sand burial, salinity, drought, and their interactions on seed germination (germination percentage, germination energy, and germination index). The results showed that sand burial and salinity stress had significant effects on the seed germination ability of S. alopecuroides, and drought stress had no significant effect, but the interaction of the three stresses had a significant effect. Under different drought-stress treatments, the interaction of no sand burial and a certain degree of salinity stress significantly improved the germination ability of S. alopecuroides, and the overall intensity of the effects of the three stresses showed that sand burial > salinity > drought. Considering the germination percentage, germination energy, and germination index of S. alopecuroides under various stress interactions, the treatment of no sand burial × 1% soil saline-alkali content × 18-20% soil water content was adopted to maximize the germination ability of S. alopecuroides. In the desert steppe area of Yanchi, Ningxia, sand burial stress was still the most limiting factor for seed germination of S. alopecuroides, and soil saline-alkali content should be increased moderately, and soil moisture should be ensured to obtain the best germination ability.

Effect of Climate and Competition on Radial Growth of Pinus sylvestris var. mongolica Forest in Hulunbuir Sandy Land of Inner Mongolia, China.

(1) Background: The forest of Pinus sylvestris var. mongolica is an important semi-arid ecosystem in Hulunbuir sandy land that plays a key role in the carbon cycle and wind erosion control. It is crucial to explore the main factors affecting the radial growth of trees of P. sylvestris var. mongolica. (2) Methods: The study established the tree-ring chronology of P. sylvestris var. mongolica and analyzed the relationships among the radial growth, competition index, and climate variables using correlation analysis and a linear mixed effect model to explore the influence of competition and climate on radial growth of P. sylvestris var. mongolica. (3) Results: The results indicated that tree growth is mainly affected by the maximum average temperature (Tmax) and precipitation in June and July of the current year and that tree growth significantly decreased with increasing competition pressure. Analysis of the linear mixed effect model showed that tree age, competition intensity, self-calibrating Palmer drought severity index (scPDSI) from May to July, and vapor pressure deficit (VPD) have a significant impact on radial growth. (4) Conclusions: The competition plays a dominant role in radial growth of P. sylvestris var. mongolica compared to climate factors. This study helps to understand the growth mechanism of P. sylvestris var. mongolica forests under climate change and provides a scientific basis for effective management of semi-arid forests.

Efficacy and safety of botulinum toxin for treating motor dysfunction in patients with Parkinson's disease: a systematic review and meta-analysis.

OBJECTIVE: To evaluate the efficacy and safety of botulinum toxin (BTX) for motor dysfunction in Parkinson's disease (PD). DESIGN: Systematic review and meta-analysis. DATA SOURCES: Searches of PubMed, EMBASE and the Cochrane Library, from database inception to 20 October 2022. ELIGIBILITY CRITERIA: Studies reported in English with adult PD patients treated with BTX. DATA EXTRACTION AND SYNTHESIS: Primary outcomes were United Parkinson's Disease Rate Scale Section (UPDRS) III (or its items) and Visual Analogue Scale (VAS). Secondary outcomes were UPDRS-II (or its items), Freezing of Gait Questionnaire (FOG-Q), Timed Up and Go test (TUG) and treatment-related adverse events (TRAEs). Mean difference (MD) or standardised MD (SMD) before and after treatment with 95% CIs were used for continuous variables and risk ratios (RRs) with 95% CIs was used for TRAEs. RESULTS: Six randomised controlled trials (RCTs) and six non-RCTs (case series) were included (ntotal=224 participants, nRCT=165). No significant difference was found in pooled results of UPDRS-III (available in four RCTs and two non-RCTs, SMD=-0.19, 95% CI -0.98 to 0.60), UPDRS-II (four RCTs and one non-RCT, SMD=-0.55, 95% CI -1.22 to 0.13), FOG-Q (one RCT and one non-RCT, SMD=0.53, 95% CI -1.93 to 2.98) or the risk of TRAEs (five RCTs, RR 0.87, 95% CI 0.37 to 2.01). Significant decreases were found in pooled VAS score (three RCTs and five non-RCTs, MD=-2.14, 95% CI -3.05 to -1.23) and TUG (MD=-2.06, 95% CI -2.91 to -1.20) after BTX treatment. CONCLUSIONS: BTX may not be associated with motor symptoms alleviation, although it benefits pain alleviation and functional mobility improvement.

Kinase POGSK-3ß modulates fungal plant polysaccharide-degrading enzyme production and development.

The filamentous fungus Penicillium oxalicum secretes integrative plant polysaccharide-degrading enzymes (PPDEs) applicable to biotechnology. Glycogen synthase kinase-3ß (GSK-3ß) mediates various cellular processes in eukaryotic cells, but the regulatory mechanisms of PPDE biosynthesis in filamentous fungi remain poorly understood. In this study, POGSK-3ß (POX_c04478), a homolog of GSK-3ß in P. oxalicum, was characterised using biochemical, microbiological and omics approaches. Knockdown of POGSK-3ß in P. oxalicum using a copper-responsive promoter replacement system led to 53.5 - 63.6%, 79.0 - 92.8% and 76.8 - 94.7% decreases in the production of filter paper cellulase, soluble starch-degrading enzyme and raw starch-degrading enzyme, respectively, compared with the parental strain ΔKu70. POGSK-3ß promoted mycelial growth and conidiation. Transcriptomic profiling and real-time quantitative reverse transcription PCR analyses revealed that POGSK-3ß dynamically regulated the expression of genes encoding major PPDEs, as well as fungal development-associated genes. The results broadened our understanding of the regulatory functions of GKS-3ß and provided a promising target for genetic engineering to improve PPDE production in filamentous fungi. KEY POINTS: • The roles of glycogen synthase kinase-3ß were investigated in P. oxalicum. • POGSK-3ß regulated PPDE production, mycelial growth and conidiation. • POGSK-3ß controlled the expression of major PPDE genes and regulatory genes.

Circadian Rhythm Disorders and Corresponding Functional Brain Abnormalities in Young Female Nurses: A Preliminary Study.

Objective: Shift work is associated with a decrease in melatonin level and perturbation of the circadian rhythm; however, it is unknown if these lead to functional brain changes. In this study, we investigated whether circadian rhythm disorders caused by shift work are related to changes in brain functional connectivity (FC) and regional homogeneity (ReHo) using whole-brain resting-state functional magnetic resonance imaging (fMRI). Methods: This prospective case-control study included nine female night shift nurses and nine age-matched female day work nurses with normal sleep rhythms. To assess sleep quality and mood, participants were asked to complete questionnaires. Serum melatonin and cortisol levels were measured. ReHo of whole-brain resting-state function and seed-based FC of the bilateral hypothalamus were compared between groups. Variables that differed significantly between groups were used to examine the association between questionnaire scores and hormone levels and fMRI data. Results: The night shift nurses had significantly lower sleep quality and melatonin levels; lower ReHo activation in the bilateral cerebellar hemisphere and higher ReHo in the bilateral occipital lobe and left parietal lobe; and higher FC from the hypothalamus to the right cingulate gyrus, right putamen, and vermis than did the day shift nurses. Activation of the right cerebellar hemisphere left superior parietal gyrus, and the right superior occipital gyrus was correlated with sleep quality scores. Moreover, activation of the right cerebellar hemisphere (r = 0.583, P = 0.011) was correlated with melatonin levels, and higher sleepiness scores were associated with stronger FC between the hypothalamus and vermis (r = 0.501, P = 0.034). Conclusions: Circadian rhythm disorder caused by night shift work can lead to a decrease in sleep quality and melatonin level, as well as a series of changes in brain FC and ReHo.

The effect of climatic and edaphic factors on soil organic carbon turnover in hummocks based on δ13C on the Qinghai-Tibet Plateau.

Hummocks (thúfur, pounus) are peculiar landforms usually formed by repeated freeze-thaw processes and differential frost heave, and are common in frost soil regions, especially in the Qinghai-Tibet Plateau. However, little is known about the response of δ13C in soil organic carbon (δ13CSOC) to soil and climate properties in hummocks. The ß value indicates the decomposition rate of soil organic carbon (SOC) in soil, and was obtained from the slope of the regression between the log10-transformed SOC concentration and δ13CSOC in soil depth profiles. In this study, we investigated δ13CSOC and SOC contents along a soil profile (0-60 cm), together with edaphic and climatic properties, both in hummocks and control plots (alpine grasslands) on the northeastern Qinghai-Tibet Plateau. Then, the variations in δ13CSOC and ß values, and the main factors affecting them, were analyzed. The results show that δ13CSOC increases with soil depth, while SOC decreases both in the hummocks and control plots. However, ß values in the hummocks were significantly (P < 0.05) higher than in the control plots while δ13CSOC showed no difference between hummock and control. Redundancy analysis showed that altitude is the main control factor for δ13CSOC and ß in the hummocks. Climate type was the main factor affecting δ13CSOC in the control plots, while mean annual precipitation and soil fractal dimension were the main factors controlling ß. Overall, climate, rather than soil, is the key factor that affects the carbon turnover rate in the hummock in the northeastern QTP. The findings of this study will expand our understanding of the soil carbon cycle and δ13CSOC changes, especially in the case of hummocks.

[Partitioning ecosystem respiration of a Platycladus orientalis forest in the west mountainous area of Beijing, China using stable carbon isotope].

Based on stable carbon isotope, we quantitatively partitioned ecosystem respiration in a Platycladus orientalis forest in the west mountainous area of Beijing. Results from this study could lay the foundation for carbon exchange research in forest ecosystems of this region. The spectroscopy technique was used to continuously measure CO2 concentrations and δ13C values at different height of the forest. Soil and branch chambers were used for measuring nighttime δ13C values in underground and aboveground respiration, and then the proportions of respiration components were calculated. Combined with soil respiration efflux measurement, ecosystem respiration was then quantitatively partitioned. The results showed that δ13C values of respiratory components fluctuated, which ranged from -31.74‰ to -23.33‰ in aboveground respiration of plants and from -32.11‰ to -27.74‰ in soil respiration. The δ13C values of ecosystem respiration was at the middle of those ranges. Soil respiration averaged 1.70 µmol·m-2·s-1 at night, accounting for 47%-91% of ecosystem respiration. Aboveground respiration averaged 0.72 µmol·m-2·s-1, contributing less to ecosystem respiration. Daytime respiration based on isotope mixing model calculation had greater variability than that based on temperature response model, with a mean value of 2.31 µmol·m-2·s-1 and 2.28 µmol·m-2·s-1, respectively.

Mini-Mental State Examination in Elderly Chinese: A Population-Based Normative Study.

BACKGROUND: Chinese nationwide norms of the Mini-Mental State Examination (MMSE) have not been established despite its wide use. OBJECTIVE: To obtain norms for the MMSE based on age, gender, education, and rural or urban residences and to determine the optimal cut-off points of the MMSE in elderly Chinese. METHODS: A cross-sectional study was conducted in Chinese community residents aged 65 years or over selected by cluster random sampling. The MMSE was administered to 9,629 subjects (7,110 cognitively normal, 2,024 with mild cognitive impairment, and 495 with dementia). The demographic influences on MMSE scores were investigated and the norms were established considering those factors. Receiver operating characteristic (ROC) analysis was used to determine the optimal cut-off points. RESULTS: Years of education (standardized ß= 0.399), rural residence (standardized ß= -0.261), age (standardized ß= -0.198), and being female (standardized ß= -0.101) had significant effects on MMSE scores (p < 0.001). Accordingly, we presented the demographic-stratified normative data for the MMSE. The optimal cut-off points for dementia screening were 16/17 for illiterate (sensitivity 87.6% and specificity 80.8%), 19/20 for individuals with 1-6 years of education (sensitivity 93.6% and specificity 92.7%), and 23/24 for individuals with 7 or more years of education (sensitivity 94.3% and specificity 94.3%). CONCLUSION: We provide the age-, gender-, education-, and residence-specific reference norms for the MMSE derived from an investigation of a large-scale, multicenter, nationwide representative Chinese elderly population. It could be of great improvement for the use of the MMSE in dementia screening in Chinese elderly population.

A Novel AßPP M722K Mutation Affects Amyloid-ß Secretion and Tau Phosphorylation and May Cause Early-Onset Familial Alzheimer's Disease in Chinese Individuals.

BACKGROUND: Mutations within exons 16 and 17 of the amyloid-ß protein precursor (AßPP) gene were the first known causes of early-onset familial Alzheimer's disease (EOFAD). Since the first AßPP mutation was reported, 39 different AßPP variations have been discovered in EOFAD. OBJECTIVE: We described a novel AßPP M722K mutation found in a Chinese familial Alzheimer's disease pedigree and confirmed its effects on amyloid-ß (Aß) secretion and tau phosphorylation. METHODS: We performed direct sequencing of exons 16 and 17 of the AßPP gene and coding exons 3-12 of the PSEN1 and PSEN2 genes for genetic analysis. N2a cells were transfected with wild-type AßPP, AßPP constructs harboring the M722K mutation, or AßPP constructs harboring the Swedish mutation to demonstrate the effects of the AßPP M722K mutation on Aß secretion and tau phosphorylation. RESULTS: Different phenotypes of patients carrying the AßPP M722K mutation maybe were related to different apolipoprotein E genotypes. The expression of AßPP M722K in mouse neuroblastoma N2a cells induced a 1.7-fold increased ratio of Aß 42 to Aß 40 without changes in sAßPPα and sAßPPß. Tau phosphorylation at the AT8 sites was also increased. CONCLUSION: Maybe the AßPP M722K mutation contributed to the cause of EOFAD in this Chinese pedigree mediated by increased Aß 42/Aß 40. Further studies should be conducted to validate the pathogenicity of AßPP M722K and the interactions among γ-secretase, APOE, and AßPP.