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

Objective:To study the implementation progress of the prevention and control measures for drinking water-borne endemic fluorosis and the changing trend of fluorosis conditions in Inner Mongolia Autonomous Region, comprehensively evaluate the effectiveness of prevention and control measures, and provide a basis for the next step of prevention and control of the disease.Methods:In 2015 and 2023, a cross-sectional survey method was used to investigate the water improvement situation, the operation of water improvement projects, the detection of fluoride level in water, and the prevalence of dental fluorosis in children aged 8 to 12 in all affected villages of 11 leagues (cities) in the entire autonomous region. The prevention and control effect of drinking water-borne endemic fluorosis in the entire autonomous region was evaluated.Results:The water improvement rates of all affected villages in the entire autonomous region in 2015 and 2023 were 84.12% (8 218/9 769) and 95.38% (8 944/9 377), respectively. The qualified rates of water fluoride in the villages with water improvement in the entire autonomous region were 66.21% (5 441/8 218) and 91.00% (8 139/8 944), respectively. The water improvement rate and water fluoride qualification rate of water improvement villages in 2023 were both higher than those in 2015, and the differences were statistically significant (χ 2 = 652.96, 1 593.81, P < 0.001). The detection rates of dental fluorosis in children aged 8 to 12 years in the entire autonomous region in 2015 and 2023 were 9.26% (7 548/81 484) and 4.46% (3 441/77 155), respectively. The detection rate of dental fluorosis in children in 2023 was lower than that in 2015, and the difference was statistically significant (χ 2 = 1 418.20, P < 0.001). In 2015 and 2023, the total compliance rate of all affected villages in the entire autonomous region reaching the control standards were 57.94% (5 660/ 9 769) and 92.37% (8 662/9 377), respectively. The total compliance rate of all affected villages in 2023 was higher than that in 2015, and the difference was statistically significant (χ 2 = 3 010.38, P < 0.001). Conclusions:Compared with 2015, the prevention and control measures of drinking water-borne endemic fluorosis in Inner Mongolia Autonomous Region have been effectively implemented in 2023, with a significant decrease in the detection rate of dental fluorosis in children. However, there are still a few affected villages that have not achieved the control standards, and prevention and control work still need to be further strengthened.

Objective:To investigate the characteristics of the population of skeletal fluorosis patients in drinking-tea-borne endemic fluorosis (referred to as drinking-tea-borne fluorosis) areas in Inner Mongolia Autonomous Region (referred to as Inner Mongolia) and the influencing factors of treatment willingness, and to provide a basis for improving the prevention and control measures of drinking-tea-borne fluorosis and the treatment plan of skeletal fluorosis.Methods:From August to October 2022, a face-to-face questionnaire survey was conducted in key areas of drinking-tea-borne fluorosis in Inner Mongolia (administrative villages with an average daily intake of tea fluoride > 3.5 mg and skeletal fluorosis patients identified by the general survey of drinking-tea-borne fluorosis in Inner Mongolia in 2019), and to investigate the demographic, severity, and treatment status of patients with skeletal fluorosis, analyze the demographic characteristics of patients with skeletal fluorosis and the influencing factors of treatment willingness.Results:A total of 734 patients with skeletal fluorosis were investigated, including 543 mild cases, 125 moderate cases and 66 severe cases. The gender ratio of patients with skeletal fluorosis was 0.71 ∶ 1.00 (305/429), the age was concentrated in > 50 - 70 years old (70.57%, 518/734), the proportion of Mongolians was 94.28% (692/734), the proportion of herders was 97.68% (717/734), the educational level was mainly primary school (54.63%, 401/734), and the proportion of poor households and immigrants who had moved to their current residence was 7.08% (52/734) and 8.04% (59/734), respectively. The distribution of the severity of skeletal fluorosis in patients of different ages, genders, and educational levels was compared, and the differences were statistically significant ( P < 0.05). Fifty-three point two seven percent (391/734) of the patients had a willingness to undergo non-pharmacological treatment, of which 69.82% (273/391) had already started non-pharmacological treatment, with a treatment effectiveness rate of 73.99% (202/273). Sixty-five point two six percent (479/734) of the patients had a willingness to receive medication treatment, of which 7.31% (35/479) had already started medication treatment, with a treatment effectiveness rate of 54.29% (19/35). Zero point two seven percent (2/734) of the patients expressed a willingness to undergo surgical treatment, while no patients underwent surgical treatment. Multivariate logistic regression analysis showed that the age, ethnicity, occupation, educational level, poverty status, immigrants status, and the severity of skeletal fluorosis were all influencing factors of non-pharmacological treatment willingness ( P < 0.05). Occupation, educational level, poverty status, immigrants status, and the severity of skeletal fluorosis were all influencing factors of medication treatment willingness ( P < 0.05). Conclusions:Patients with skeletal fluorosis caused by tea drinking in Inner Mongolia are mainly from Mongolian ethnic groups, herders, middle-aged and elderly people, and those with a lower educational levels. The willingness of patients to receive treatment is influenced by various factors, and corresponding intervention measures can be formulated and taken based on these influencing factors to effectively improve the disease prevention awareness and treatment willingness of patients and the public.

Objective:To study the implementation progress of the prevention and control measures for drinking water-borne endemic fluorosis and the changing trend of fluorosis conditions in Inner Mongolia Autonomous Region, comprehensively evaluate the effectiveness of prevention and control measures, and provide a basis for the next step of prevention and control of the disease.Methods:In 2015 and 2023, a cross-sectional survey method was used to investigate the water improvement situation, the operation of water improvement projects, the detection of fluoride level in water, and the prevalence of dental fluorosis in children aged 8 to 12 in all affected villages of 11 leagues (cities) in the entire autonomous region. The prevention and control effect of drinking water-borne endemic fluorosis in the entire autonomous region was evaluated.Results:The water improvement rates of all affected villages in the entire autonomous region in 2015 and 2023 were 84.12% (8 218/9 769) and 95.38% (8 944/9 377), respectively. The qualified rates of water fluoride in the villages with water improvement in the entire autonomous region were 66.21% (5 441/8 218) and 91.00% (8 139/8 944), respectively. The water improvement rate and water fluoride qualification rate of water improvement villages in 2023 were both higher than those in 2015, and the differences were statistically significant (χ 2 = 652.96, 1 593.81, P < 0.001). The detection rates of dental fluorosis in children aged 8 to 12 years in the entire autonomous region in 2015 and 2023 were 9.26% (7 548/81 484) and 4.46% (3 441/77 155), respectively. The detection rate of dental fluorosis in children in 2023 was lower than that in 2015, and the difference was statistically significant (χ 2 = 1 418.20, P < 0.001). In 2015 and 2023, the total compliance rate of all affected villages in the entire autonomous region reaching the control standards were 57.94% (5 660/ 9 769) and 92.37% (8 662/9 377), respectively. The total compliance rate of all affected villages in 2023 was higher than that in 2015, and the difference was statistically significant (χ 2 = 3 010.38, P < 0.001). Conclusions:Compared with 2015, the prevention and control measures of drinking water-borne endemic fluorosis in Inner Mongolia Autonomous Region have been effectively implemented in 2023, with a significant decrease in the detection rate of dental fluorosis in children. However, there are still a few affected villages that have not achieved the control standards, and prevention and control work still need to be further strengthened.

Objective:To investigate the characteristics of the population of skeletal fluorosis patients in drinking-tea-borne endemic fluorosis (referred to as drinking-tea-borne fluorosis) areas in Inner Mongolia Autonomous Region (referred to as Inner Mongolia) and the influencing factors of treatment willingness, and to provide a basis for improving the prevention and control measures of drinking-tea-borne fluorosis and the treatment plan of skeletal fluorosis.Methods:From August to October 2022, a face-to-face questionnaire survey was conducted in key areas of drinking-tea-borne fluorosis in Inner Mongolia (administrative villages with an average daily intake of tea fluoride > 3.5 mg and skeletal fluorosis patients identified by the general survey of drinking-tea-borne fluorosis in Inner Mongolia in 2019), and to investigate the demographic, severity, and treatment status of patients with skeletal fluorosis, analyze the demographic characteristics of patients with skeletal fluorosis and the influencing factors of treatment willingness.Results:A total of 734 patients with skeletal fluorosis were investigated, including 543 mild cases, 125 moderate cases and 66 severe cases. The gender ratio of patients with skeletal fluorosis was 0.71 ∶ 1.00 (305/429), the age was concentrated in > 50 - 70 years old (70.57%, 518/734), the proportion of Mongolians was 94.28% (692/734), the proportion of herders was 97.68% (717/734), the educational level was mainly primary school (54.63%, 401/734), and the proportion of poor households and immigrants who had moved to their current residence was 7.08% (52/734) and 8.04% (59/734), respectively. The distribution of the severity of skeletal fluorosis in patients of different ages, genders, and educational levels was compared, and the differences were statistically significant ( P < 0.05). Fifty-three point two seven percent (391/734) of the patients had a willingness to undergo non-pharmacological treatment, of which 69.82% (273/391) had already started non-pharmacological treatment, with a treatment effectiveness rate of 73.99% (202/273). Sixty-five point two six percent (479/734) of the patients had a willingness to receive medication treatment, of which 7.31% (35/479) had already started medication treatment, with a treatment effectiveness rate of 54.29% (19/35). Zero point two seven percent (2/734) of the patients expressed a willingness to undergo surgical treatment, while no patients underwent surgical treatment. Multivariate logistic regression analysis showed that the age, ethnicity, occupation, educational level, poverty status, immigrants status, and the severity of skeletal fluorosis were all influencing factors of non-pharmacological treatment willingness ( P < 0.05). Occupation, educational level, poverty status, immigrants status, and the severity of skeletal fluorosis were all influencing factors of medication treatment willingness ( P < 0.05). Conclusions:Patients with skeletal fluorosis caused by tea drinking in Inner Mongolia are mainly from Mongolian ethnic groups, herders, middle-aged and elderly people, and those with a lower educational levels. The willingness of patients to receive treatment is influenced by various factors, and corresponding intervention measures can be formulated and taken based on these influencing factors to effectively improve the disease prevention awareness and treatment willingness of patients and the public.

Objective To prepare a variety of quality control(QC)materials for SARS-CoV-2 variants as an addition to the conven-tional SARS-CoV-2 nucleic acid QC products for the laboratory detection of mutant strains by optimizing the preparation and purification process of MS2 phage virus-like particle(VLP)technique,and evaluate their performances.Methods The typical mutation sequence fragments or full length S genes were designed and synthesized according to the genomic information of SARS-CoV-2 variants.Then,they were inserted into the downstream of maturase gene,coat protein and the pac-site of MS2 phage to construct a series of recombi-nant expression vectors.After induced by the prokaryotic expression system,the VLP products were purified through the polyethylenei-mine precipitation,ultrafiltration,nuclease digestion,and gel filtration chromatography.The obtained VLP were validated by the nucle-ic acid electrophoresis,protein electrophoresis,protein concentration determination,and fluorescence PCR,and their performances such as nucleic acid residue and stability were also evaluated.Results A total of 10 kinds of VLP containing the targeted sequences of the gene to be tested were prepared.The length of the foreign sequence wrapped in them ranged from 297 bp to 3 822 bp,which could be combined into a variety of QC materials for the mutation detection of different SARS-CoV-2 variants.The prepared VLP QC materials could not be effectively amplified without nucleic acid extraction or reverse transcription steps during the routine nucleic acid detection.The simulated QC samples remained stable after repeated freeze-thaw cycles.They could be stored stably for 2 months at 25 ℃ and 4 weeks at 37 ℃.Conclusion The established preparation and combined purification process of VLP QC materials can encapsulate vari-ous exogenous nucleic acid sequences with different lengths into the viral coat protein to form VLP,with high production efficiency.The VLP QC products prepared by the above process have stable performance and almost no residual exogenous nucleic acid,which can ef-fectively meet clinical requirements and ensure the quality of laboratory testing.

Objective To prepare a variety of quality control(QC)materials for SARS-CoV-2 variants as an addition to the conven-tional SARS-CoV-2 nucleic acid QC products for the laboratory detection of mutant strains by optimizing the preparation and purification process of MS2 phage virus-like particle(VLP)technique,and evaluate their performances.Methods The typical mutation sequence fragments or full length S genes were designed and synthesized according to the genomic information of SARS-CoV-2 variants.Then,they were inserted into the downstream of maturase gene,coat protein and the pac-site of MS2 phage to construct a series of recombi-nant expression vectors.After induced by the prokaryotic expression system,the VLP products were purified through the polyethylenei-mine precipitation,ultrafiltration,nuclease digestion,and gel filtration chromatography.The obtained VLP were validated by the nucle-ic acid electrophoresis,protein electrophoresis,protein concentration determination,and fluorescence PCR,and their performances such as nucleic acid residue and stability were also evaluated.Results A total of 10 kinds of VLP containing the targeted sequences of the gene to be tested were prepared.The length of the foreign sequence wrapped in them ranged from 297 bp to 3 822 bp,which could be combined into a variety of QC materials for the mutation detection of different SARS-CoV-2 variants.The prepared VLP QC materials could not be effectively amplified without nucleic acid extraction or reverse transcription steps during the routine nucleic acid detection.The simulated QC samples remained stable after repeated freeze-thaw cycles.They could be stored stably for 2 months at 25 ℃ and 4 weeks at 37 ℃.Conclusion The established preparation and combined purification process of VLP QC materials can encapsulate vari-ous exogenous nucleic acid sequences with different lengths into the viral coat protein to form VLP,with high production efficiency.The VLP QC products prepared by the above process have stable performance and almost no residual exogenous nucleic acid,which can ef-fectively meet clinical requirements and ensure the quality of laboratory testing.

Objective:To investigate the distribution of physical and chemical water improvement areas of drinking water-borne endemic fluorosis in Inner Mongolia Autonomous Region, as well as the use of household water purifiers.Methods:From April to October 2021, a survey was conducted in a drinking water-borne endemic fluorosis areas in Inner Mongolia Autonomous Region where physical and chemical water improvement was carried out. The survey included the basic situation of the affected villages (number of permanent households, number of permanent residents, historical water fluoride content) and the use of residential water purifiers. Household peripheral water samples were collected to test the water fluoride content. Water purifier installation rate, normal usage rate, qualified water fluoride rate in normal usage, and the proportion of households covered by filter replacement departments were calculated.Results:In Inner Mongolia Autonomous Region, the physical and chemical water improvement areas of drinking water-borne endemic fluorosis were distributed in 2 735 villages in 11 leagues (cities) throughout the region, with 192 950 permanent households and 540 216 permanent residents. The average historical water fluoride content in all leagues (cities) was 2.18 mg/L, and the current average water fluoride content was 0.40 mg/L. A total of 134 763 water purifiers were installed, with an installation rate of 69.84% (134 763/192 950). A total of 10 773 households were surveyed, with 10 396 households using water purifiers normally and a normal usage rate of 96.50% (10 396/10 773). Among them, 10 158 households had qualified water fluoride of normal usage, with a qualified water fluoride rate of 97.71% (10 158/10 396). Of the 10 396 households using water purifiers normally, 3 974 households (38.23%) had filter cartridges used within one year, and 3 961 households had qualified water fluoride, with a qualified rate of water fluoride of 99.67% (3 961/3 974). Six thousand four hundred and twenty-two households (61.77%) had filter cartridges used for more than one year, with 6 197 households had qualified water fluoride and a qualified rate of water fluoride of 96.50% (6 197/6 422). There was a statistically significant difference in the qualified rate of water fluoride between purifiers with different filter cartridge usage times (χ 2 = 110.73, P < 0.001). Among the 10 773 surveyed households, the filter cartridges replacement department covered 10 470 households, accounting for 97.19% (10 470/10 773). Conclusions:In Inner Mongolia Autonomous Region, the physical and chemical water improvement areas of drinking water-borne endemic fluorosis are widely distributed, and the normal usage rate of household water purifiers is relatively high. The qualified rate of water fluoride in household water purifiers with filter cartridges used for more than one year is low.

Objective:To investigate the epidemic status of drinking-tea type endemic fluorosis (fluorosis for short) in Inner Mongolia Autonomous Region (Inner Mongolia for short), and to provide theoretical basis and basic data for formulation and evaluation of prevention and control measures.Methods:From May to October 2022, a cross-sectional survey was conducted in key areas (168 administrative villages in 6 leagues or cities) identified in the 2019 regional census with tea drinking habits, daily per capita intake of tea fluoride > 3.5 mg, and patients with skeletal fluorosis. The drinking condition of brick tea in 10 households of each administrative village was investigated, and the brick tea samples were collected to detect fluoride level. The prevalence of dental fluorosis in children aged 8 - 12 and skeletal fluorosis in adults aged 16 and older was investigated, and urine samples of patients with skeletal fluorosis were collected to detect urinary fluoride levels.Results:Totally 98.40% (1 657/1 684) of the households in the surveyed areas had a habit of drinking brick tea, with an annual per capita consumption of brick tea and a daily per capita intake of tea fluoride of 5.07 kg and 5.38 mg, respectively. The qualified rate of fluoride level in brick tea samples was 55.64% (922/1 657), the average fluoride level of all other brick tea varieties exceeded the national standard limit (300 mg/kg) except for black brick tea (291.08 mg/kg). Totally 2 747 children aged 8 to 12 were examined, with a detection rate of 13.91% (382/2 747) for dental fluorosis. The disease was mainly mild. There was no statistically significant difference in the detection rate of dental fluorosis among different age groups (χ 2 = 5.53, P = 0.238). Totally 71 708 adults aged 16 and older were examined, and the detection rate of skeletal fluorosis was 1.02% (734/71 708). Patients were mainly aged between 50 and 70 years old, and the condition in each age group was mainly mild. Totally 715 urine samples of skeletal fluorosis patients were collected and tested, and 55.24% (395/715) of the urine samples had fluoride levels higher than 1.6 mg/L. Conclusions:In Inner Mongolia, the proportion of high fluoride brick tea in endemic areas of drinking-tea type fluorosis is high. The detection rates of dental fluorosis in children and skeletal fluorosis in adults are relatively high. The prevention and control situation of drinking-tea type fluorosis is still serious.

Objective:To investigate the epidemic scope and intensity of drinking water type endemic arsenic poisoning in Inner Mongolia Autonomous Region, as well as the prevalence and influencing factors, in order to provide scientific basis for precise formulation of prevention and control measures.Methods:A sampling survey was conducted on residents' drinking water in all villages and counties in Inner Mongolia Autonomous Region, water samples were selected according to different water supply methods (engineering water supply, physical and chemical water purification, and decentralized water supply), and the arsenic content was detected by atomic fluorescence method. The "Diagnosis of Endemic Arsenicosis" (WS/T 211-2015) was used for diagnosis of arsenic poisoning among all permanent residents who were exposing to or had been exposed to excessively high arsenic water, in order to search all the arsenic poisoning patients. Analyze the distribution of water arsenic in the historical disease areas and high arsenic villages and newly discovered high arsenic villages, and explore the prevalence and influencing factors of arsenic poisoning.Results:There were a total of 1 186 historical disease areas and high arsenic villages in Inner Mongolia Autonomous Region, mainly distributed in 28 banner counties of 8 league cities such as Bayannur, Hohhot and Baotou, with a regional distribution trend of more in the west and less in the east. At present, the water improvement rate in the historical disease areas and high arsenic villages was 98.23% (1 165/1 186), and the qualified rate of arsenic content in the water was 99.83% (1 184/1 186). The arsenic content in the water of historical disease areas and high arsenic villages ranged from 0.000 to 0.093 mg/L. Four newly discovered villages with arsenic exceeding standards had been found, and their arsenic content ranged from 0.074 to 0.142 mg/L. A total of 2 249 patients with arsenic poisoning were detected in the confirmed disease area/high arsenic villages, and the detection rate was 1.67% (2 249/134 645). The number of patients in Bayannur City was the largest with the most severe disease, accounting for 82.70% (1 860/2 249). Patients aged 60 and above accounted for 61.41% of the total cases (1 381/2 249), which was higher than other age groups (χ 2 = 840.52, P < 0.001). The detection rate of arsenic poisoning was higher in males than in females (χ 2 = 132.38, P < 0.001). There are statistically significant differences in the detection rate and severity distribution of arsenic poisoning patients among different water arsenic content groups(χ 2 = 1 557.85, 1 741.05, P < 0.001). Conclusions:After years of prevention and control work, the arsenic content in most historical disease areas and high arsenic villages in Inner Mongolia Autonomous Region is currently qualified, and some areas have water arsenic exceeding standards or newly discovered villages with arsenic exceeding standards. At the same time, there are still a large number of arsenic poisoning patients in Inner Mongolia Autonomous Region. In the future, the prevention and control of endemic arsenic poisoning in Inner Mongolia Autonomous Region cannot be relaxed, and it is necessary to strengthen water quality monitoring and improve water quality in newly discovered villages with arsenic exceeding standards to prevent the occurrence of new cases.