OBJECTIVE: To explore and quantify the association of hot night exposure during the sperm development period (0-90 lag days) with semen quality. METHODS: A total of 6,640 male sperm donors from 6 human sperm banks in China during 2014-2020 were recruited in this multicenter study. Two indices (i.e., hot night excess [HNE] and hot night duration [HND]) were used to estimate the heat intensity and duration during nighttime. Linear mixed models were used to examine the association between hot nights and semen quality parameters. RESULTS: The exposure-response relationship revealed that HNE and HND during 0-90 days before semen collection had a significantly inverse association with sperm motility. Specifically, a 1 °C increase in HNE was associated with decreased sperm progressive motility of 0.0090 (95% confidence interval [ CI]: -0.0147, -0.0033) and decreased total motility of 0.0094 (95% CI: -0.0160, -0.0029). HND was significantly associated with reduced sperm progressive motility and total motility of 0.0021 (95% CI: -0.0040, -0.0003) and 0.0023 (95% CI: -0.0043, -0.0002), respectively. Consistent results were observed at different temperature thresholds on hot nights. CONCLUSION Our findings highlight the need to mitigate nocturnal heat exposure during spermatogenesis to maintain optimal semen quality.
Humans ; Male ; Semen Analysis ; Adult ; Sperm Motility ; Hot Temperature/adverse effects* ; China ; Middle Aged ; Spermatozoa/physiology* ; Young Adult

OBJECTIVE: To assess health equity in the Yangtze River region to improve understanding of the correlation between hand, foot, and mouth disease (HFMD) and socioeconomic factors. METHODS: From 2014-2016, data on HFMD incidence, population statistics, economic indicators, and meteorology from 26 cities along the Yangtze River were analyzed. A multi-city random-effects meta-analysis was performed to study the relationship between temperature and HFMD transmission, and health equity was assessed with respect to socio-economic impact. RESULTS: Over the study period, 919,458 HFMD cases were reported, with Shanghai (162,303) having the highest incidence and Tongling (5,513) having the lowest. Males were more commonly affected (male-to-female ratio, 1.49:1). The exposure-response relationship had an M-shaped curve, with two HFMD peaks occurring at 4 °C and 26 °C. The relative risk had two peaks at 1.30 °C (1.834, 95% CI: 1.204-2.794) and 31.4 °C (1.143, 95% CI: 0.901-1.451), forming an M shape, with the first peak higher than the second. The most significant impact of temperature on HFMD was observed between -2 °C and 18.1 °C. The concentration index (0.2463) indicated moderate concentration differences, whereas the Theil index (0.0418) showed low inequality in distribution. CONCLUSION The incidence of HFMD varied across cities, particularly with changes in temperature. Economically prosperous areas showed higher risks, indicating disparities. Targeted interventions in these areas are crucial for mitigating the risk of HFMD.
Female ; Humans ; Male ; China/epidemiology* ; Cities/epidemiology* ; Hand, Foot and Mouth Disease/transmission* ; Incidence ; Risk Factors ; Temperature

OBJECTIVE: The role of cold spells of different intensities in the economic burden of death is crucial for health adaptation to climate change, especially in a multi-site setting. The objective of the study was to explore the economic burden of mortality attributable to cold spells. METHODS: We performed a two-stage time-series analysis using the Value of Statistical Life (VSL) approach to evaluate the economic impact of mortality related to cold spells of varying lengths and intensities. This analysis employed a case-crossover design, with a distributed lag nonlinear model (DLNM) used for analysis. Analysis was stratified according to age, sex, and region of origin. The results of the assessment show that cold spells have an enormous impact on the economic losses of mortality due to climate change and aging. RESULTS: Totally, 8.3% (95% CI: 0.0%, 16.0%) to 13.8% (95% CI: 1.0%, 24.8%) of VSL were ascribed to cold spells, accounting for economic losses of 4.71 (95% CI: 0.34, 8.47) to 11.45 (95% CI: 0.00, 21.00) billion CNY, in the cold season. The population aged over 65 y and females are particularly vulnerable. Economic impacts in warmer regions, such as the southern and subtropical zones, are more extensive than those in the northern and temperate zones. CONCLUSION Customizing cold spell prevention measures for vulnerable populations or regions is vital to alleviating the socioeconomic burden.
China/epidemiology* ; Humans ; Female ; Male ; Cold Temperature/adverse effects* ; Aged ; Middle Aged ; Adult ; Mortality ; Infant ; Child ; Adolescent ; Child, Preschool ; Young Adult ; Climate Change ; Aged, 80 and over ; Cost of Illness ; Infant, Newborn

OBJECTIVE: To assess relationships between cold spells and genitourinary hospitalization risk. METHODS: Hospitalization records for genitourinary system diseases (GUDs) from 16 districts in Beijing (2013-2018) were analyzed. Cold spells were defined based on varying intensity thresholds. A two-stage analytical method was employed: first, generalized linear models assessed district-specific associations between cold spells and hospitalizations; second, random-effects meta-analysis aggregated the district-level results. Subgroup analyses were performed by admission type (emergency vs. outpatient), age, and sex. RESULTS: A total of 271,579 GUD-related hospitalizations were recorded. Cold spells (p1day2，daily mean temperature below the 1 ^st percentiles of the daily mean temperature distribution from January 1, 2013, to December 31, 2018, lasting for two or more consecutive days) were linked to a significant rise in hospitalization risks: 1.43 (95% CI: 1.32-1.56) for all GUDs, 1.35 (95% CI: 1.23-1.49) for urinary system diseases, and 1.46 (95% CI: 1.28-1.67) for renal failure, when compared to non-cold spell days. Emergency admissions showed higher risk increases than outpatient admissions. CONCLUSION Extreme cold spells significantly elevate hospitalization risks for GUDs. This highlights the urgent need for targeted public health interventions to mitigate cold-related health impacts, especially for vulnerable populations.
Humans ; Hospitalization/statistics & numerical data* ; Male ; Female ; Cold Temperature/adverse effects* ; Infant ; Child, Preschool ; Middle Aged ; Adult ; Child ; Aged ; Adolescent ; Young Adult ; Beijing/epidemiology* ; Female Urogenital Diseases/etiology* ; Male Urogenital Diseases/etiology* ; Infant, Newborn ; Risk Factors

OBJECTIVES: This study aims to analyze the clinical symptoms and imaging manifestations in patients with temporomandibular disorder syndrome (TMD), who are sensitive to sudden temperature drop. METHODS: One hundred and nineteen patients with TMD who attended the Department of Stomatology of the First Medical Center of Chinese People's Liberation Army General Hospital from December 2022 to December 2023 were included, including 44 males and 75 females, with a mean age of 32.4±13.7 years.The questionnaire was used to determine whether they were sensitive to temperature drop, and the TMD patients were divided into a temperature plunge-sensitive group and a temperature drop insensitive group. The clinical symptoms and imaging manifestations of patients in the two groups were observed. SPSS 25.0 was used for statistical analysis. RESULTS: There was no statistically significant difference between the gender and age of patients in the temperature plunge-sensitive group (50 patients) and the insensitivity group (69 patients) (P>0.05). The percentage of patients with pain was slightly higher in the temperature plunge-sensitive group [86.0% (43/50)] than in the insensitive group [68.1% (47/69)], and the difference was statistically significant (χ²=5.031, P=0.025), while the differences in joint murmur and mouth opening limitation between the two groups were not statistically significant. A total of 238 lateral joints were detected in both groups, the percentage of osteoarthropathic imaging changes was significantly higher in the temperature plunge-sensitive group [82.0% (82/100)] than in the insensitive group [53.6% (74/138)] (χ²=20.675, P<0.001). Magnetic imaging showed that the percentage of joint effusion was higher in patients in the temperature plunge-sensitive group [66.0% (33/50)] than in the insensitive group [42.0% (29/69)], and the difference was statistically significant (χ²=5.602, P=0.018). CONCLUSIONS TMD patients with maxillofacial pain symptoms, joint effusions, and abnormal imaging of osteoarticular structures are more likely to be sensitive to sudden temperature drops.
Humans ; Male ; Female ; Adult ; Temporomandibular Joint Disorders/diagnosis* ; Surveys and Questionnaires ; Middle Aged ; Young Adult ; Temperature ; Adolescent

Glucose oxidase (GOD) is an oxygen-consuming dehydrogenase that can catalyze the production of gluconic acid hydrogen peroxide from glucose, and its specific mechanism of action makes it promising for applications, while the low catalytic activity and poor thermostability have become the main factors limiting the industrial application of this enzyme. In this study, we used the glucose oxidase AtGOD reported with the best thermostability as the source sequence for phylogenetic analysis to obtain the GOD with excellent performance. Six genes were screened and successfully synthesized for functional validation. Among them, the glucose oxidase AhGODB derived from Aspergillus heteromorphus was expressed in Pichia pastoris and showed better thermostability and catalytic activity, with an optimal temperature of 40 ℃, a specific activity of 112.2 U/mg, and a relative activity of 47% after 5 min of treatment at 70 ℃. To improve its activity and thermal stability, we constructed several mutants by directed evolution combined with rational design. Compared with the original enzyme, the mutant T72R/A153P showcased the optimum temperature increasing from 40 to 50 ℃, the specific activity increasing from 112.2 U/mg to 166.1 U/mg, and the relative activity after treatment at 70 ℃ for 30 min increasing from 0% to 33%. In conclusion, the glucose oxidase mutants obtained in this study have improved catalytic activity and thermostability, and have potential for application.
Glucose Oxidase/chemistry* ; Enzyme Stability ; Aspergillus/genetics* ; Pichia/metabolism* ; Temperature ; Catalysis ; Fungal Proteins/metabolism* ; Hot Temperature

To screen and identify a chitosanase with high stability, we cloned the chitosanase gene from Bacillus atrophaeus with a high protease yield from the barren saline-alkali soil and expressed this gene in Escherichia coli. The expressed chitosanase of B. atrophaeus (BA-CSN) was purified by nickel-affinity column chromatography. The properties including optimal temperature, optimal pH, substrate specificity, and kinetic parameters of BA-CSN were characterized. The results showed that BA-CSN had the molecular weight of 31.13 kDa, the optimal temperature of 55 ℃, the optimal pH 5.5, and good stability at temperatures below 45 ℃ and pH 4.0-9.0. BA-CSN also had good stability within 4 h of pH 3.0 and 10.0, be activated by K⁺, Na⁺, Mn²⁺, Ca²⁺, Mg²⁺, and Co²⁺, (especially by Mn²⁺), and be inhibited by Fe³⁺, Cu²⁺, and Ag⁺. BA-CSN showcased the highest relative activity in the hydrolysis of colloidal chitosan, and it had good hydrolysis ability for colloidal chitin. Under the optimal catalytic conditions, BA-CSN demonstrated the Michaelis constant K_m and maximum reaction rate V_max of 9.94 mg/mL and 26.624 μmoL/(mL·min), respectively, for colloidal chitosan. In short, BA-CSN has strong tolerance to acids and alkali, possessing broad industrial application prospects.
Bacillus/genetics* ; Hydrogen-Ion Concentration ; Escherichia coli/metabolism* ; Glycoside Hydrolases/biosynthesis* ; Substrate Specificity ; Enzyme Stability ; Chitosan/metabolism* ; Temperature ; Kinetics ; Cloning, Molecular ; Bacterial Proteins/biosynthesis* ; Recombinant Proteins/genetics*

The PIF7 gene is a member of the bHLH family, playing a pivotal role in plant germination. However, its roles in tea plants (Camellia sinensis) remain largely unexplored. In this study, we cloned the phytochrome-interacting factor gene CsPIF7 to elucidate its role in the germination of tea plants. Subcellular localization analysis demonstrated that CsPIF7 was localized in the nucleus. Yeast one-hybrid and dual-luciferase reporter assays demonstrated that CsPIF7 directly bound to a specific region (7-321 bp) of the CsEXP promoter, thereby repressing the expression of CsEXP. These findings suggest that CsPIF7 may modulate the germination of tea plants by inhibiting the expression of CsEXP. Quantitative real-time PCR results showed that both CsPIF7 and CsEXP exhibited high expression levels in tea buds, with different expression patterns in response to abscisic acid (ABA) treatment. Furthermore, both CsPIF7 and CsEXP were upregulated under cold stress at 4 ℃, indicating their involvement in the cold response of tea plants. Taken together, these results suggest that CsPIF7 regulates CsEXP expression in an ABA-dependent manner, thereby influencing the germination of tea plants. This study provides both theoretical and experimental insights into the molecular mechanisms governing the germination of tea plants, laying the groundwork for further exploring the role of PIF7 in plant development and stress responses.
Camellia sinensis/metabolism* ; Gene Expression Regulation, Plant ; Plant Proteins/metabolism* ; Abscisic Acid/pharmacology* ; Germination/genetics* ; Basic Helix-Loop-Helix Transcription Factors/metabolism* ; Promoter Regions, Genetic ; Cold Temperature

The plant AT-rich sequence and zinc-binding protein (PLATZ) family is composed of plant-specific zinc finger-like transcription factors, which play important roles in plant growth, development, and stress tolerance. In this study, to gain a better understanding of the PLATZ gene in C. sinensis and elucidate its response under drought and high temperature conditions, the PLATZ gene family of the C. sinensis cultivar 'Tieguanyin' was systematically identified, and a total of 12 CsPLATZ family members were identified. Expasy online and other bioinformatics tools were used to analyze the members of the PLATZ gene family in terms of protein physicochemical properties, phylogenetic relationships, cis-acting elements, gene structures, and intra- and inter-species collinearity. The results of phylogenetic analysis classified the CsPLATZ family members into 2 subfamilies. The conserved domains and gene structures of PLATZ family members within the same subfamily had a high degree of consistency, whereas a certain degree of diversity was observed among the subfamilies. Twelve PLATZ genes were unevenly distributed across 7 chromosomes of C. sinensis and the promoter regions of these genes had multiple cis-acting elements related to hormone and stress responses. The collinearity analysis showed that there were 4 pairs of duplication events in the CsPLATZ gene family, all of which were segmental duplications. Based on this gene family, C. sinensis had a closer evolutionary relationship with A. thaliana than with O. sativa. The transcriptome analysis showed that the expression levels of CsPLATZ family members varied in different tissue samples of C. sinensis. 6 genes (CsPLATZ-1, CsPLATZ-2, CsPLATZ-3, CsPLATZ-4, CsPLATZ-6, and CsPLATZ-8) with high expression in shoots, young leaves, and roots were selected for high temperature and drought stress treatments, and their expression was quantified by qRT-PCR. The results indicated that the six genes might play important roles in the response to drought stress. In addition, CsPLATZ-2 and CsPLATZ-8 might have important functions in the response to high temperature stress. The results of this study will contribute to a better understanding of the biological functions of PLATZ genes and their possible roles in the growth, development, and stress responses of C. sinensis.
Droughts ; Camellia sinensis/physiology* ; Phylogeny ; Gene Expression Regulation, Plant ; Plant Proteins/genetics* ; Stress, Physiological/genetics* ; Multigene Family ; Transcription Factors/genetics* ; Hot Temperature ; Genes, Plant

Rice (Oryza sativa L.), as a thermophilic crop, is highly susceptible to cold stress during its growth process. Chilling injury at the plumule stage and seedling stage often affects the morphological development and leads to yield reduction of rice. The exploration and utilization of cold tolerance genes are among the most direct and effective approaches to address cold stress in rice. To identify quantitative trait loci (QTLs) associated with cold tolerance at plumule and seedling stages, in this study, we measured the seedling rates and survived seedling rates of the indica rice cultivar 'HZ', the japonica cultivar 'Nekken2', and their 120 recombinant inbred lines (RILs) under cold stress. A previously constructed high-density genetic linkage map was used for the mapping of the QTLs conferring cold tolerance at the plumule and seedling stages. A total of 4 QTLs for plumule-stage cold tolerance and 9 QTLs for seedling-stage cold tolerance were detected, with the maximum limit of detection reaching 5.20. Notably, a genetically overlapping QTL for both plumule and seedling stages was identified on chromosome 8, spanning a physical interval of 24 432 953-25 295 129 bp. Candidate genes within the detected QTL intervals were screened, and quantitative real-time polymerase chain reaction (qRT-PCR) was conducted to analyze the gene expression during the plumule and seedling stages. The results revealed that LOC_Os03g06570, LOC_Os03g07100, LOC_Os06g08280, LOC_Os08g38440, LOC_Os08g39100, and LOC_Os08g39540 exhibited significantly differential expression between the parental lines. These genes were either significantly downregulated or upregulated under cold stress. Among them, the first three gene (LOC_Os03g06570, LOC_Os03g07100, and LOC_Os06g08280) were hypothesized to be key candidates regulating the cold tolerance of rice seedlings, while the latter three genes (LOC_Os08g38440, LOC_Os08g39100, and LOC_Os08g39540) were identified as comprehensive regulators of cold tolerance during both plumule and seedling stages. These findings lay a foundation for the fine mapping and cloning of cold tolerance genes at the plumule and seedling stages, providing valuable insights for breeding cold-tolerant rice varieties.
Quantitative Trait Loci/genetics* ; Oryza/growth & development* ; Seedlings/growth & development* ; Cold Temperature ; Chromosome Mapping ; Gene Expression Regulation, Plant