AIM:To establish a cell model of visceral hypersensitivity and nerve hyperplasia in irritable bowel syndrome(IBS)by conducting an in vitro co-culture of mouse P815 mast cells and N2a nerve cells and explore its possible mechanism.METHODS:Enzyme-linked immunosorbent assay(ELISA)with three replicates was used to confirm the C48/80-induced P815 degranulation.The length of neurites was observed under bright field microscopy to determine the number of differentiated neurons,thereby selecting the concentration of retinoic acid(RA)for stimulating the differentia-tion of N2a cells,with four replicates.A co-culture system of P815 and N2a cells was established using Transwell cham-bers with four replicates.The following groups were established:N2a cells cultured alone,N2a cells co-cultured with P815 cells,N2a cells co-cultured with P815 cells plus C48/80,and N2a cells plus RA group.After co-culturing,the num-ber of differentiated N2a cells was observed under bright field.The expression of nerve growth factor(NGF),tyrosine ki-nase receptor A(TRKA),growth-associated protein-43(GAP43),neuron-specific enolase(NSE),synapsin(SYN),and postsynaptic density protein-95(PSD-95)at both protein and gene levels in N2a cells was detected using Western blot and polymerase chain reaction(PCR),with four replicates.RESULTS:The best condition for N2a differentiation was stimulation with 10 μmol/L RA for 24 hours,whereas the best condition for degranulation was stimulation of P815 cells with 20 mg/L C48/80 for 24 hours.Compared with N2a cells cultured alone,the differentiation ratio of the N2a+P815+C48/80 and N2a+RA groups was significantly increased(P<0.01),and the protein and mRNA expressions of NGF,TRKA,GAP43,NSE,SYN,and PSD-95 were significantly increased(P<0.05).CONCLUSION:Our results revealed that mast cell degranulation enhances the level of nerve hyperplasia in enteric nerve cells and promotes changes in nerve structure and function.Synaptic remodeling regulated by abnormal expression of key proteins such as NGF,TRKA,and GAP43 is involved in the nerve hyperplasia induced by mast cell degranulation.

Objective To analyze the differences of brain activity between first-episode untreated depressive patients with and without suicidal ideation(SI),and its correlations with clinical characteristics.Methods A total of 40 major depressive disorder(MDD)patients with SI(MDD+SI group),40 patients without SI MDD(MDD+NSI group),and 40 healthy controls(HC)(HC group)were enrolled.The 17-item Hamilton depression scale(HAMD-17)and Beck scale for suicide ideation(BSI)were used to assess the severity of depression and SI,respectively.MRI data were collected.The values of fractional amplitude of low-frequency fluctuation(fALFF)were calculated.Results(1)Compared with the HC group,the MDD+NSI group showed decreases in the fALFF val-ues of the default network and attention network.The fALFF values of the attention network in the MDD+SI group showed decreases.Compared with the MDD+NSI group,the MDD+SI group showed decreases in the fALFF values of the attention network.(2)The fALFF values in the left middle frontal gyrus were negatively correlated with the total score of HAMD-17(r=-0.55;P<0.001)in the MDD+NSI group,while the fALFF values in the left middle frontal gyrus were negatively correlated with the total score of HAMD-17(r=-0.53;P<0.001)and the total score of BSI(r=-0.51;P<0.001)in the MDD+SI group.(3)The optimal critical value of fALFF value in left middle frontal gyrus for predicting SI occurrence in MDD patients was-0.039,area under the curve(AUC)was 0.76,sensitivity was 0.63,and specificity was 0.80.Conclusion The decreased local activity intensity in the left middle frontal gyrus of the brain might be the central mechanism for the occurrence of SI in MDD patients.In addition,the left middle frontal gyrus might have certain value in identifying SI and predicting the severity of SI.

Objective To investigate the global burden of visceral leishmaniasis (VL) from 1990 to 2021 and predict the trends in the burden of VL from 2022 to 2035, so as to provide insights into global VL prevention and control. Methods The global age-standardized incidence, prevalence, mortality and disability-adjusted life years (DALYs) rates of VL and their 95% uncertainty intervals (UI) were captured from the Global Burden of Disease Study 2021 (GBD 2021) data resources. The trends in the global burden of VL were evaluated with average annual percent change (AAPC) and 95% confidence interval (CI) from 1990 to 2021, and gender-, age-, country-, geographical area- and socio-demographic index (SDI)-stratified burdens of VL were analyzed. The trends in the global burden of VL were projected with a Bayesian age-period-cohort (BAPC) model from 2022 to 2035, and the associations of age-standardized incidence, prevalence, mortality, and DALYs rates of VL with SDI levels were examined with a smoothing spline model. Results The global age-standardized incidence [AAPC = -0.25%, 95% CI: (-0.25%, -0.24%)], prevalence [AAPC = -0.06%, 95% CI: (-0.06%, -0.06%)], mortality [AAPC = -0.25%, 95% CI: (-0.25%, -0.24%)] and DALYs rates of VL [AAPC = -2.38%, 95% CI: (-2.44%, -2.33%)] all appeared a tendency towards a decline from 1990 to 2021, and the highest age-standardized incidence [2.55/10⁵, 95% UI: (1.49/10⁵, 4.07/10⁵)], prevalence [0.64/10⁵, 95% UI: (0.37/10⁵, 1.02/10⁵)], mortality [0.51/10⁵, 95% UI: (0, 1.80/10⁵)] and DALYs rates of VL [33.81/10⁵, 95% UI: (0.06/10⁵, 124.09/10⁵)] were seen in tropical Latin America in 2021. The global age-standardized incidence and prevalence of VL were both higher among men [0.57/10⁵, 95% UI: (0.45/10⁵, 0.72/10⁵); 0.14/10⁵, 95% UI: (0.11/10⁵, 0.18/10⁵)] than among women [0.27/10⁵, 95% UI: (0.21/10⁵, 0.33/10⁵); 0.06/10⁵, 95% UI: (0.05/10⁵, 0.08/10⁵)], and the highest mortality of VL was found among children under 5 years of age [0.24/10⁵, 95% UI: (0.08/10⁵, 0.66/10⁵)]. The age-standardized incidence (r = -0.483, P < 0.001), prevalence (r = -0.483, P < 0.001), mortality (r = -0.511, P < 0.001) and DALYs rates of VL (r = -0.514, P < 0.001) correlated negatively with SDI levels from 1990 to 2021. In addition, the global burden of VL was projected with the BAPC model to appear a tendency towards a decline from 2022 to 2035, and the age-standardized incidence, prevalence, mortality and DALYs rates were projected to be reduced to 0.11/10⁵, 0.03/10⁵, 0.02/10⁵ and 1.44/10⁵ in 2035, respectively. Conclusions Although the global burden of VL appeared an overall tendency towards a decline from 1990 to 2021, the burden of VL showed a tendency towards a rise in Central Asia and western sub-Saharan African areas. The age-standardized incidence and prevalence rates of VL were relatively higher among men, and the age-standardized mortality of VL was relatively higher among children under 5 years of age. The global burden of VL was projected to continue to decline from 2022 to 2035.

OBJECTIVE: To investigate the associations between eight serum per- and polyfluoroalkyl substances (PFASs) and regional fat depots, we analyzed the data from the National Health and Nutrition Examination Survey (NHANES) 2011-2018 cycles. METHODS: Multiple linear regression models were developed to explore the associations between serum PFAS concentrations and six fat compositions along with a fat distribution score created by summing the concentrations of the six fat compositions. The associations between structurally grouped PFASs and fat distribution were assessed, and a prediction model was developed to estimate the ability of PFAS exposure to predict obesity risk. RESULTS: Among females aged 39-59 years, trunk fat mass was positively associated with perfluorooctane sulfonate (PFOS). Higher concentrations of PFOS, perfluorohexane sulfonate (PFHxS), perfluorodecanoate (PFDeA), perfluorononanoate (PFNA), and n-perfluorooctanoate (n-PFOA) were linked to greater visceral adipose tissue in this group. In men, exposure to total perfluoroalkane sulfonates (PFSAs) and long-chain PFSAs was associated with reductions in abdominal fat, while higher abdominal fat in women aged 39-59 years was associated with short-chain PFSAs. The prediction model demonstrated high accuracy, with an area under the curve (AUC) of 0.9925 for predicting obesity risk. CONCLUSION PFAS exposure is associated with regional fat distribution, with varying effects based on age, sex, and PFAS structure. The findings highlight the potential role of PFAS exposure in influencing fat depots and obesity risk, with significant implications for public health. The prediction model provides a highly accurate tool for assessing obesity risk related to PFAS exposure.
Humans ; Fluorocarbons/blood* ; Female ; Adult ; Middle Aged ; Male ; Environmental Pollutants/blood* ; Abdominal Fat ; Nutrition Surveys ; Alkanesulfonic Acids/blood* ; Obesity ; Environmental Exposure

Body weight abnormalities, including overweight, obesity, and underweight, have become a dual public health challenge in Chinese adults: overweight and obesity lead to a variety of chronic complications, while underweight increases the risks of malnutrition, sarcopenia, and organ dysfunction. To systematically address these issues, multidisciplinary experts in endocrinology, sports science, nutrition, and psychiatry from various regions have held multiple weight management seminars. Based on the latest epidemiological data and clinical evidence, they expanded the guideline to include assessment and intervention strategies for underweight, in addition to the core content of obesity management. This guideline outlines the etiological mechanisms, evaluation methods, and multidimensional management strategies for overweight and obesity, covering key areas such as diagnosis and assessment, medical nutrition therapy, exercise prescription, pharmacological intervention, and psychological support. It is intended to provide a scientific and standardized approach to weight management across the adult population, aiming to curb the rising prevalence of obesity, mitigate complications associated with abnormal body weight, and improve nutritional status and overall quality of life.

Objective:To explore the differences in the ability of different parts of the human skin to recognize vibration frequencies in order to provide data for physiological optimization of vibration parameters in pilots′ tactile vests.Methods:Ten healthy volunteers were selected and grouped by age as 20-40 years (6 cases) and 41-50 years (4 cases). All the subjects participated in 3 trials: ① identification test of frequency steps using cutaneous tactile perception: the back of the left hand was chosen as the test area, a dual-oscillator synchronous vibration system was adopted, and the frequency step was gradually increased (initially 0.1 Hz) to determine the threshold of frequency identification; ② maximum frequency threshold test of cutaneous tactile perception: the maximum frequency recognition thresholds in 7 parts of the trunk (the left waist, right waist, chest, back, left shoulder, right shoulder, neck) and the back of the hand were tested; ③ frequency discrimination test of cutaneous tactile perception: 5 equally spaced frequencies (covering the frequency recognition thresholds) were set to evaluate the accuracy of tactile frequency memory on the back of the hand after 3, 15 min and 24 h. The relationships between the adjacent step sizes of cutaneous tactile perception and the average value of the sum of adjacent frequencies were analyzed using simple linear regression. The highest identification thresholds of frequencies in different parts of the subjects as well as the accuracy of frequency discrimination during different periods were compared across the age groups.Results:The maximum thresholds of frequency identification of cutaneous tactile perception among the 10 subjects ranged from 16.20 to 33.55 Hz, while the range of adjacent step sizes was between 3.60 and 7.10 Hz. The adjacent step sizes were positively correlated with the average value of the sum of adjacent frequencies ( r=0.882, F=529.18, P<0.001). In the test on the maximum threshold of frequency identification of cutaneous tactile perception, there was a statistically significant difference in the main effect of an age group between the 2 groups ( F=15.87, P<0.001), but not in the main effect of the site ( P>0.05), or in the interactions between the group and age ( P>0.05). The accuracies of skin vibration frequency memory on the dorsal hand of the subjects at 3, 15 min and 24 h were 88%, 72% and 68% respectively. In the frequency discrimination test, there were no statistically significant differences in the main effect of the group, main effect of time or in their interactions between the 2 groups (all P>0.05). Conclusions:The ability of the human skin to identify vibration frequency is impacted by age, but there is no difference in sensitivity between the trunk and the back of the hand. It is recommended that the tactile vest for pilots be designed for general purposes to make it easy to adapt to vibration frequencies of multiple parts.

Objective To analyze the differences of brain activity between first-episode untreated depressive patients with and without suicidal ideation(SI),and its correlations with clinical characteristics.Methods A total of 40 major depressive disorder(MDD)patients with SI(MDD+SI group),40 patients without SI MDD(MDD+NSI group),and 40 healthy controls(HC)(HC group)were enrolled.The 17-item Hamilton depression scale(HAMD-17)and Beck scale for suicide ideation(BSI)were used to assess the severity of depression and SI,respectively.MRI data were collected.The values of fractional amplitude of low-frequency fluctuation(fALFF)were calculated.Results(1)Compared with the HC group,the MDD+NSI group showed decreases in the fALFF val-ues of the default network and attention network.The fALFF values of the attention network in the MDD+SI group showed decreases.Compared with the MDD+NSI group,the MDD+SI group showed decreases in the fALFF values of the attention network.(2)The fALFF values in the left middle frontal gyrus were negatively correlated with the total score of HAMD-17(r=-0.55;P<0.001)in the MDD+NSI group,while the fALFF values in the left middle frontal gyrus were negatively correlated with the total score of HAMD-17(r=-0.53;P<0.001)and the total score of BSI(r=-0.51;P<0.001)in the MDD+SI group.(3)The optimal critical value of fALFF value in left middle frontal gyrus for predicting SI occurrence in MDD patients was-0.039,area under the curve(AUC)was 0.76,sensitivity was 0.63,and specificity was 0.80.Conclusion The decreased local activity intensity in the left middle frontal gyrus of the brain might be the central mechanism for the occurrence of SI in MDD patients.In addition,the left middle frontal gyrus might have certain value in identifying SI and predicting the severity of SI.

AIM:To establish a cell model of visceral hypersensitivity and nerve hyperplasia in irritable bowel syndrome(IBS)by conducting an in vitro co-culture of mouse P815 mast cells and N2a nerve cells and explore its possible mechanism.METHODS:Enzyme-linked immunosorbent assay(ELISA)with three replicates was used to confirm the C48/80-induced P815 degranulation.The length of neurites was observed under bright field microscopy to determine the number of differentiated neurons,thereby selecting the concentration of retinoic acid(RA)for stimulating the differentia-tion of N2a cells,with four replicates.A co-culture system of P815 and N2a cells was established using Transwell cham-bers with four replicates.The following groups were established:N2a cells cultured alone,N2a cells co-cultured with P815 cells,N2a cells co-cultured with P815 cells plus C48/80,and N2a cells plus RA group.After co-culturing,the num-ber of differentiated N2a cells was observed under bright field.The expression of nerve growth factor(NGF),tyrosine ki-nase receptor A(TRKA),growth-associated protein-43(GAP43),neuron-specific enolase(NSE),synapsin(SYN),and postsynaptic density protein-95(PSD-95)at both protein and gene levels in N2a cells was detected using Western blot and polymerase chain reaction(PCR),with four replicates.RESULTS:The best condition for N2a differentiation was stimulation with 10 μmol/L RA for 24 hours,whereas the best condition for degranulation was stimulation of P815 cells with 20 mg/L C48/80 for 24 hours.Compared with N2a cells cultured alone,the differentiation ratio of the N2a+P815+C48/80 and N2a+RA groups was significantly increased(P<0.01),and the protein and mRNA expressions of NGF,TRKA,GAP43,NSE,SYN,and PSD-95 were significantly increased(P<0.05).CONCLUSION:Our results revealed that mast cell degranulation enhances the level of nerve hyperplasia in enteric nerve cells and promotes changes in nerve structure and function.Synaptic remodeling regulated by abnormal expression of key proteins such as NGF,TRKA,and GAP43 is involved in the nerve hyperplasia induced by mast cell degranulation.

Body weight abnormalities, including overweight, obesity, and underweight, have become a dual public health challenge in Chinese adults: overweight and obesity lead to a variety of chronic complications, while underweight increases the risks of malnutrition, sarcopenia, and organ dysfunction. To systematically address these issues, multidisciplinary experts in endocrinology, sports science, nutrition, and psychiatry from various regions have held multiple weight management seminars. Based on the latest epidemiological data and clinical evidence, they expanded the guideline to include assessment and intervention strategies for underweight, in addition to the core content of obesity management. This guideline outlines the etiological mechanisms, evaluation methods, and multidimensional management strategies for overweight and obesity, covering key areas such as diagnosis and assessment, medical nutrition therapy, exercise prescription, pharmacological intervention, and psychological support. It is intended to provide a scientific and standardized approach to weight management across the adult population, aiming to curb the rising prevalence of obesity, mitigate complications associated with abnormal body weight, and improve nutritional status and overall quality of life.

Objective:To explore the differences in the ability of different parts of the human skin to recognize vibration frequencies in order to provide data for physiological optimization of vibration parameters in pilots′ tactile vests.Methods:Ten healthy volunteers were selected and grouped by age as 20-40 years (6 cases) and 41-50 years (4 cases). All the subjects participated in 3 trials: ① identification test of frequency steps using cutaneous tactile perception: the back of the left hand was chosen as the test area, a dual-oscillator synchronous vibration system was adopted, and the frequency step was gradually increased (initially 0.1 Hz) to determine the threshold of frequency identification; ② maximum frequency threshold test of cutaneous tactile perception: the maximum frequency recognition thresholds in 7 parts of the trunk (the left waist, right waist, chest, back, left shoulder, right shoulder, neck) and the back of the hand were tested; ③ frequency discrimination test of cutaneous tactile perception: 5 equally spaced frequencies (covering the frequency recognition thresholds) were set to evaluate the accuracy of tactile frequency memory on the back of the hand after 3, 15 min and 24 h. The relationships between the adjacent step sizes of cutaneous tactile perception and the average value of the sum of adjacent frequencies were analyzed using simple linear regression. The highest identification thresholds of frequencies in different parts of the subjects as well as the accuracy of frequency discrimination during different periods were compared across the age groups.Results:The maximum thresholds of frequency identification of cutaneous tactile perception among the 10 subjects ranged from 16.20 to 33.55 Hz, while the range of adjacent step sizes was between 3.60 and 7.10 Hz. The adjacent step sizes were positively correlated with the average value of the sum of adjacent frequencies ( r=0.882, F=529.18, P<0.001). In the test on the maximum threshold of frequency identification of cutaneous tactile perception, there was a statistically significant difference in the main effect of an age group between the 2 groups ( F=15.87, P<0.001), but not in the main effect of the site ( P>0.05), or in the interactions between the group and age ( P>0.05). The accuracies of skin vibration frequency memory on the dorsal hand of the subjects at 3, 15 min and 24 h were 88%, 72% and 68% respectively. In the frequency discrimination test, there were no statistically significant differences in the main effect of the group, main effect of time or in their interactions between the 2 groups (all P>0.05). Conclusions:The ability of the human skin to identify vibration frequency is impacted by age, but there is no difference in sensitivity between the trunk and the back of the hand. It is recommended that the tactile vest for pilots be designed for general purposes to make it easy to adapt to vibration frequencies of multiple parts.