Objective:To study the effects of chronic fluoride exposure on spatial learning and memory and the expression of phosphatidylinositol 3-kinase (PI3K), protein kinase B (Akt), and mammalian target of rapamycin (mTOR) in hippocampus of second offspring (F2 generation) rats.Methods:Sixteen clean-grade healthy SD pregnant rats were randomly divided into four groups according to their body mass [(200 ± 50) g] using a random number table method: the control group [0 mg/L sodium fluoride (NaF)], and the low, medium, and high fluoride groups (60, 120, 240 mg/L NaF), with four rats in each group. Fluoride exposure was carried out from the 0th day of pregnancy to the 21st day of birth (PND21) of first offspring (F1 generation) rats through free drinking water. The F1 generation rats continued to be exposed to fluoride at the same dose and method as the female rats in the same group until the 90th day of birth (PND90). Six rats (male to female ratio 2∶1) were selected from each group and housed together. Female F1 were continuously exposed with the same method until PND21 of the F2 generation rats. Eight F2 generation rats (4 males and 4 females, with a male to female ratio of 1∶1 in the same litter) were randomly selected from each group and exposed to NaF with corresponding concentrations from PND22 to PND90. Before the execution of F2 generation rats, Morris water maze experiment was used to examine spatial learning and memory ability. After execution, real-time fluorescence quantitative PCR (qRT-PCR) and Western blotting were used to detect the mRNA and protein expression levels of PI3K, Akt, and mTOR in the hippocampus, respectively.Results:Compared with the control group days 2 - 4 [(46.72 ± 4.24), (24.87 ± 3.15), (14.10 ± 2.52) s], the escape latency of F2 generation rats was prolonged in the medium and high fluoride groups on the second day [(53.96 ± 3.45), (54.48 ± 6.20) s] and on the fourth day [(19.47 ± 2.51), (25.02 ± 3.86) s], and in the low, medium and high fluoride groups on the third day [(32.37 ± 4.56), (37.32 ± 4.65), (41.79 ± 7.08) s, P < 0.05]. Compared with the control group, the first arrival time of F2 generation rats in the high fluoride group was prolonged, while the number of crossing platforms in both the medium and high fluoride groups decreased ( P < 0.05). Except for mTOR mRNA in the low fluoride group, the mRNA and protein expression levels of PI3K, Akt, mTOR in the hippocampus of rats in all other exposure groups were lower than those in the control group ( P < 0.05). The results of correlation analysis showed that NaF concentration was positively correlated with the escape latency and the first arrival time of F2 generation rats on days 1 - 4 ( r = 0.44, 0.57, 0.79, 0.80, 0.58, P < 0.05), and negatively correlated with the mRNA and protein expression levels of PI3K, Akt, mTOR in the hippocampus of F2 generation rats, as well as the number of crossing platforms ( r = - 0.71, - 0.67, - 0.73, - 0.61, - 0.58, - 0.71, - 0.82, P < 0.05). Conclusion:Chronic fluoride exposure can lead to spatial learning and memory impairment in F2 generation rats, and its mechanism of action may be related to the inhibition of the PI3K/Akt/mTOR signaling pathway in the hippocampus.
Objective:To analyze the monitoring results of skeletal fluorosis in coal-burning type endemic fluorosis areas in Guizhou Province, and evaluate the effectiveness of comprehensive treatment of coal-burning type endemic fluorosis in the affected areas.Methods:In 2009, 2014, and 2019, monitoring of skeletal fluorosis was carried out in six counties (cities, districts) of Renhuai City, Qixingguan District, Dafang County, Qianxi City, Puding County, and Pu'an County in Guizhou Province. Age stratification was conducted in each county (city, district) for permanent residents aged 25 and above, and survey subjects were selected for X-ray examination of skeletal fluorosis.Results:The detection rates of skeletal fluorosis in 2009, 2014, and 2019 were 51.48% (798/1 550), 34.88% (308/883), and 6.51% (60/922), respectively, showing a decreasing trend year by year (χ 2trend = 505.83, P < 0.001), decreased by 44.97 percentage points from 2009 to 2019. The age distribution of patients with skeletal fluorosis was mainly in the age group of 55 years and older, with annual proportions of 53.88% (430/798), 56.49% (174/308), and 78.33% (47/60), all higher than 50%. In 2009, 2014, and 2019, 483, 222 and 21 cases of mild skeletal fluorosis were detected, and 315, 86, and 39 cases of moderate to severe skeletal fluorosis were detected. There was a statistically significant difference in disease grading among different years(χ 2 = 32.63, P < 0.001). Among them, there were statistically significant differences in the grading of skeletal fluorosis in Qixingguan District, Qianxi City, Puding County, and Pu'an County(χ 2 = 14.56, 12.24, 35.01, 23.35, P < 0.05). Conclusions:The detection rate of skeletal fluorosis in Guizhou Province decreases year by year, and the prevention and control effect is significant. Patients with skeletal fluorosis are mainly in the age group of 55 years and older, and the proportion of patients with moderate to severe skeletal fluorosis is increasing. We should continue to monitor and manage the treatment of current patients with skeletal fluorosis.
Objective:To study the effects of water fluoride and tea fluoride on the occurrence of dental fluorosis in children, and to provide a basis for scientific prevention and control of the disease.Methods:From April to September 2020, Baolongshan Town with qualified water fluoride but no habit of drinking brick tea, Xingyao Town with qualified water fluoride and habit of drinking brick tea, Baokang Town with exceeded water fluoride but no habit of drinking brick tea, and Wuliyasitai Town with exceeded water fluoride and habit of drinking brick tea were selected as survey sites in Inner Mongolia Autonomous Region based on historical monitoring data. In all Gacha (villages) of 4 towns, a survey was carried out on residents' drinking water, brick tea drinking habits and children's dental fluorosis detection, and the water fluoride, tea fluoride exceeding standard rates, daily per capita intake of brick tea fluoride and the detection rate of children's dental fluorosis were calculated. At the same time, multivariate logistic regression was used to analyze the influencing factors affecting the occurrence of dental fluorosis in children.Results:In 2020, a total of 165 water samples were collected in 4 towns of Inner Mongolia Autonomous Region, and the total water fluoride exceeding standard rate was 38.18% (63/165). A total of 320 tea samples were collected, the tea fluoride exceeding standard rates in Xingyao Town and Wuliyasitai Town were 96.38% (213/221) and 89.90% (89/99), respectively; the daily per capita intake of brick tea fluoride was 5.67 and 7.35 mg, respectively. A total of 1 652 children were examined for dental fluorosis, and 639 cases were detected, the detection rate was 38.68%. The detection rates of dental fluorosis in boys and girls were 37.18% (322/866) and 40.33% (317/786), respectively, with no significant difference between sexes (χ 2 = 1.72, P = 0.104); the detection rates of dental fluorosis in children aged 8 - 12 years were 43.93% (105/239), 40.50% (147/363), 46.57% (163/350), 30.56% (88/288) and 33.01% (136/412), respectively, with statistical significant difference among ages (χ 2 = 26.07, P < 0.001); the detection rates of dental fluorosis in children in Baolongshan, Baokang, Xingyao and Wuliyasitai towns were 0.68% (2/293), 14.09% (31/220), 24.79% (89/359) and 66.28% (517/780), respectively, with statistical significant differences among regions (χ 2 = 213.05, P < 0.001). Multivariate logistic regression analysis showed that when the fluoride content in water was 1.2 - < 2.0, 2.0 - < 2.5, and ≥2.5 mg/L, the risk of dental fluorosis in children was 3.93, 6.60, and 9.02 times of water fluoride content < 1.2 mg/L; when the daily per capita intakes of brick tea fluoride was 3.6 - 7.0 and > 7.0 mg, the risk of dental fluorosis in children was 2.94 and 3.90 times of daily per capita intakes of brick tea fluoride ≤3.5 mg; the risk of dental fluorosis in children aged 10 years was 1.81 times of children aged 8 years; the risk of dental fluorosis in children in Xingyao, Baokang, and Wuliyasitai towns was 22.35, 40.93, and 151.58 times of Baolongshan Town, respectively. Conclusions:The prevalence of dental fluorosis in children still exists in Inner Mongolia Autonomous Region, and the detection rate of dental fluorosis is high. High water fluoride and high tea fluoride are the main risk factors for dental fluorosis in children.
Objective:To study the clinical characteristics of patients with brucella bloodstream infection in different age groups, and provide a basis for clinicians to take targeted diagnosis and treatment measures. Methods:Demographic data and general condition (age, sex, occupation, location, onset season, source of infection, clinical stage), clinical characteristics (main clinical symptoms and complications), and laboratory test results (routine and pathogenic tests) of adult patients with brucella bloodstream infection admitted to the Affiliated Hospital of Chengde Medical College from January 2015 to January 2020 were collected. According to the age stratification standards recommended by the World Health Organization, the patients were divided into a young group (18 - 44 years old), a middle-aged group (45 - 59 years old), and an elderly group (≥60 years old), and various indicators among different age groups were compared and analyzed. Results:A total of 75 patients were included, including 15 cases (20.00%) in the young group, 37 cases (49.33%) in the middle-aged group, and 23 cases (30.67%) in the elderly group. Among them, 61 cases (81.33%) were males and 14 cases (18.67%) were females, with statistically significant differences in gender ratios among different age groups (χ 2 = 7.28, P = 0.021). The majority of patients were farmers (64 cases, 85.33%), and 92.00% (69/75) of the patients came from rural areas. The main sources of infection were infected cattle and sheep, and contaminated food (39 cases, 52.00%). The main season of onset was spring and summer (45 cases, 60.00%). The clinical staging was mainly in the acute phase (66 cases, 88.00%). In terms of clinical symptoms, the young group of patients had no symptoms of low back pain, while the incidence rates of low back pain in the middle-aged and elderly groups were 35.14% (13/37) and 30.43% (7/23), respectively. There was a statistically significant difference between the three groups (χ 2 = 6.98, P = 0.031). In terms of complications, there were no cases of concurrent spondylitis in the young group of patients. The incidence rates of spondylitis in the middle-aged and elderly groups were 32.43% (12/37) and 34.78% (8/23), respectively. There was a statistically significant difference among the three groups (χ 2 = 6.86, P = 0.032). In terms of routine laboratory examinations, there were statistically significant differences in the proportion of blood lymphocytes and albumin levels among patients of different age groups ( F = 3.41, 3.27, P = 0.038, 0.044). In terms of pathogenic examination, there was a statistically significant difference in the median alarm time for positive blood culture among patients of different age groups ( H = 9.54, P = 0.008), with the middle-aged group having the longest (66.24 h) and the elderly group having the shortest (58.80 h). Conclusions:The clinical characteristics of patients with brucella bloodstream infection vary among different age groups, middle-aged and elderly patients are prone to low back pain symptoms, accompanied by spondylitis. Clinicians should pay attention to the patient's own characteristics and provide targeted diagnosis and treatment.
Fluorine is widely present in nature, and long-term excessive intake of fluoride by the body can cause damages to bone tissues such as teeth and bones, as well as non bone tissues and organs such as nervous, cardiovascular, digestive and immune systems. Fluoride can cause apoptosis and autophagy of spleen lymphocytes, ultimately leading to damage to the structure and function of spleen. This article reviews the research progress of signaling pathways related to fluoride induced spleen immune function damage, in order to provide a theoretical basis for molecular mechanism study.
