Objective: To analyze the change trends in the body shape indicators and proportions of students in Harbin from 2010 to 2024, and to investigate ergonomic compatibility of functional dimensions of school desks and chairs with current student shape indicators, so as to provide a reference for revising furniture standards of desks and chairs. Methods: Between September and November of both 2010 and 2024, a combination of convenience sampling and stratified cluster random sampling was conducted across three districts in Harbin, yielding samples of 6 590 and 6 252 students, respectively. Anthropometric shape indicators cluding height, sitting height, crus length, and thigh length-and their proportional changes were compared over the 15-year period. The 2024 data were compared with current standard functional dimensions of school furniture. The statistical analysis incorporated t-test and Mann-Whitney U- test. Results: From 2010 to 2024, average height increased by 1.8 cm for boys and 1.5 cm for girls; sitting height increased by 1.5 cm for both genders; crus length increased by 0.3 cm for boys and 0.4 cm for girls; and thigh length increased by 0.5 cm for both genders. The ratios of sitting height to height, and sitting height to leg length increased by less than 0.1 . The difference between desk chair height and 1/3 sitting height ranged from 0.4-0.8 cm. Among students matched with size 0 desks and chairs, 22.0% had a desk to chair height difference less than 0, indicating that the desk to chair height difference might be insufficient for taller students. The differences between seat height and fibular height ranged from -1.4 to 1.1 cm; and the differences between seat depth and buttock popliteal length ranged from -9.8 to 3.4 cm. Among obese students, the differences between seat width and 1/2 hip circumference ranged from -20.5 to -8.7 cm, while it ranged from -12.2 to -3.8 cm among non obese students. Conclusion Current furniture standards basically satisfy hygienic requirements; however, in the case of exceptionally tall and obese students, ergonomic accommodations such as adaptive seating allocation or personalized adjustments are recommended to meet hygienic requirements.

Background: Nasopharyngeal carcinoma (NPC) is characterized by high programmed death-ligand 1 (PD-L1) expression and abundant infiltration of non-malignant lymphocytes, which renders patients potentially suitable candidates for immune checkpoint blockade therapies. Palate, lung, and nasal epithelium clone (PLUNC) inhibit the growth of NPC cells and enhance cellular apoptosis and differentiation. Currently, the relationship between PLUNC (as a tumor-suppressor) and PD-L1 in NPC is unclear. Methods: We collected clinical samples of NPC to verify the relationship between PLUNC and PD-L1. PLUNC plasmid was transfected into NPC cells, and the variation of PD-L1 was verified by western blot and immunofluorescence. In NPC cells, we verified the relationship of PD-L1, activating transcription factor 3 (ATF3), and β-catenin by western blot and immunofluorescence. Later, we further verified that PLUNC regulates PD-L1 through β-catenin. Finally, the effect of PLUNC on β-catenin was verified by co-immunoprecipitation (Co-IP). Results: We found that PLUNC expression was lower in NPC tissues than in paracancer tissues. PD-L1 expression was opposite to that of PLUNC. Western blot and immunofluorescence showed that β-catenin could upregulate ATF3 and PD-L1, while PLUNC could downregulate ATF3/PD-L1 by inhibiting the expression of β-catenin. PLUNC inhibits the entry of β-catenin into the nucleus. Co-IP experiments demonstrated that PLUNC inhibited the interaction of DEAD-box helicase 17 (DDX17) and β-catenin. Conclusions PLUNC downregulates the expression of PD-L1 by inhibiting the interaction of DDX17/β-catenin in NPC.

Background: Nasopharyngeal carcinoma (NPC) is characterized by high programmed death-ligand 1 (PD-L1) expression and abundant infiltration of non-malignant lymphocytes, which renders patients potentially suitable candidates for immune checkpoint blockade therapies. Palate, lung, and nasal epithelium clone (PLUNC) inhibit the growth of NPC cells and enhance cellular apoptosis and differentiation. Currently, the relationship between PLUNC (as a tumor-suppressor) and PD-L1 in NPC is unclear. Methods: We collected clinical samples of NPC to verify the relationship between PLUNC and PD-L1. PLUNC plasmid was transfected into NPC cells, and the variation of PD-L1 was verified by western blot and immunofluorescence. In NPC cells, we verified the relationship of PD-L1, activating transcription factor 3 (ATF3), and β-catenin by western blot and immunofluorescence. Later, we further verified that PLUNC regulates PD-L1 through β-catenin. Finally, the effect of PLUNC on β-catenin was verified by co-immunoprecipitation (Co-IP). Results: We found that PLUNC expression was lower in NPC tissues than in paracancer tissues. PD-L1 expression was opposite to that of PLUNC. Western blot and immunofluorescence showed that β-catenin could upregulate ATF3 and PD-L1, while PLUNC could downregulate ATF3/PD-L1 by inhibiting the expression of β-catenin. PLUNC inhibits the entry of β-catenin into the nucleus. Co-IP experiments demonstrated that PLUNC inhibited the interaction of DEAD-box helicase 17 (DDX17) and β-catenin. Conclusions PLUNC downregulates the expression of PD-L1 by inhibiting the interaction of DDX17/β-catenin in NPC.

Background: Nasopharyngeal carcinoma (NPC) is characterized by high programmed death-ligand 1 (PD-L1) expression and abundant infiltration of non-malignant lymphocytes, which renders patients potentially suitable candidates for immune checkpoint blockade therapies. Palate, lung, and nasal epithelium clone (PLUNC) inhibit the growth of NPC cells and enhance cellular apoptosis and differentiation. Currently, the relationship between PLUNC (as a tumor-suppressor) and PD-L1 in NPC is unclear. Methods: We collected clinical samples of NPC to verify the relationship between PLUNC and PD-L1. PLUNC plasmid was transfected into NPC cells, and the variation of PD-L1 was verified by western blot and immunofluorescence. In NPC cells, we verified the relationship of PD-L1, activating transcription factor 3 (ATF3), and β-catenin by western blot and immunofluorescence. Later, we further verified that PLUNC regulates PD-L1 through β-catenin. Finally, the effect of PLUNC on β-catenin was verified by co-immunoprecipitation (Co-IP). Results: We found that PLUNC expression was lower in NPC tissues than in paracancer tissues. PD-L1 expression was opposite to that of PLUNC. Western blot and immunofluorescence showed that β-catenin could upregulate ATF3 and PD-L1, while PLUNC could downregulate ATF3/PD-L1 by inhibiting the expression of β-catenin. PLUNC inhibits the entry of β-catenin into the nucleus. Co-IP experiments demonstrated that PLUNC inhibited the interaction of DEAD-box helicase 17 (DDX17) and β-catenin. Conclusions PLUNC downregulates the expression of PD-L1 by inhibiting the interaction of DDX17/β-catenin in NPC.

Objective To investigate the application value of spectral computed tomography venography(CTV)in the display and staging of deep venous thrombosis(DVT)in the lower extremity.Methods Eighty-two patients with CTV were selected and ran-domly divided into group A(42 patients)and group B(40 patients).Group A:tube voltage 120 kVp.Group B:gemstone spectral ima-ging(GSI)mode,reconstruction of 50 keV and iodine(water)maps.The CT and standard deviation(SD)values of the veins were measured,signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)were calculated in 120 kVp images of group A and in 50 keV images of group B.Two observers scored the image quality of the 2 groups subjectively,and Kappa test was used to examine the con-sistency.Based on the duration from the occurrence of clinical symptoms,the DVTs were classified.The CT values and iodine con-centration(IC)of DVT were measured in the 120 kVp images of group A and in the iodine(water)maps of group B,respectively.The receiver operating characteristic(ROC)curve was drawn to compare the effectiveness of CT values and IC in diagnosing DVT staging.Results CT values,SNR,and CNR of veins in group B were higher than those in group A(P<0.05).The subjective scores of the two groups were consistent(Kappa=0.926-0.955,P<0.05).The score for the display of veins and thrombus clarity in group B was 5(4,5),which was better than the score of 4(3,4)in group A(P<0.05).The efficiency of IC in diagnosing DVT staging[area under the curve(AUC)=0.973]was better than that of CT values(AUC=0.891).Conclusion The spectral CTV can improve the contrast of lower extremity deep veins and the clarity of thrombus,and can provide more objective indicators for the diagnosis of thrombus staging,which is conducive to accurate clinical diagnosis and treatment.

Objective To perform laboratory detection and molecular traceability analysis on a case of imported kala-azar in Shenzhen to determine the infection strain. Methods Bone marrow puncture fluid and blood samples from a case of kala-azar in Shenzhen were collected for laboratory tests. The patient's bone marrow puncture fluid smears were stained with Giemsa and examined under a microscope. Blood samples were examined for antibodies using the rk39 visceral leishmania rapid diagnostic reagent. Whole blood DNA was extracted, and the ITS-1 sequence was amplified by PCR, sequenced and aligned, and a phylogenetic tree was constructed based on the ITS-1 sequence. Results Microscopic examination of the patient's bone marrow smears revealed a large number of Leishmania amastigotes without flagella, confirming the diagnosis of kala-azar. The patient's blood was tested positive with the rk39 rapid diagnostic reagent, and PCR amplification yielded an ITS-1 gene product sequence that matched the expected size. Sequence alignment with the NCBI database showed 100% sequence similarity with the ITS-1 gene sequence of Leishmania infantum, confirming the infecting strain as Leishmania infantum. Phylogenetic tree construction of the amplified ITS-1 sequence revealed clustering into a clade with Leishmania infantum , and close to KC347299, one of the reference sequence selected. Conclusions The case of kala-azar in Shenzhen was caused by Leishmania infantum. Kala-azar still occurs in China, so the diagnostic technology of medical personnel in non-epidemic areas should be strengthened so that they can actively use new diagnostic technologies to assist in diagnosis, thus improving their prevention and control ability of Leishmania parasites.

Objective:To investigate the arsenic metabolism pattern and possible influencing factors in the population in drinking-water-borne endemic arsenic poisoning (drinking-water-borne arsenic poisoning for short) areas.Methods:In December 2004, a cluster sampling method was used to select arsenic poisoning population (arsenic poisoning group) and healthy population (control group) in drinking-water-borne arsenic poisoning area of Bayannur City, Inner Mongolia Autonomous Region as the survey subjects. A questionnaire survey was conducted. Arsenic content in drinking water at home of survey subjects, the levels of urinary arsenic and its metabolites, including [trivalent arsenic (As Ⅲ), inorganic arsenic (iAs), monomethylarsenic acid (pentavalent, MMA V), dimethylarsenic acid (pentavalent, DMA V), total arsenic (tAs), percentage of inorganic arsenic (iAs%), percentage of monomethylarsenic acid (MMA%), percentage of dimethylarsenic acid (DMA%), primary methylation index (PMI), secondary methylation index (SMI)] were tested using high performance liquid chromatography-inductively coupled plasma mass spectrometry; nail arsenic and nail selenium levels were tested using atomic fluorescence spectrometer. The influencing factors of arsenic metabolism pattern were analyzed by multiple linear regression. Results:A total of 536 survey subjects were included, including 155 individuals in the arsenic poisoning group and 381 in the control group. The water arsenic level ranged from 0.0 to 825.7 μg/L. Compared with the control group, there was no significant difference in the distribution of gender, education level and dental fluorosis in the arsenic poisoning group ( P > 0.05), but there were significant differences in the distribution of age, marital status, smoking, drinking and water arsenic ( P < 0.05). Compared with the control group, the levels of urinary As Ⅲ, iAs, MMA V, DMA V, tAs, MMA%, MMA/DMA and nail arsenic in the arsenic poisoning group were higher ( P < 0.05), while the levels of urinary DMA%, SMI and nail selenium were lower ( P < 0.05); but there was no statistically significant difference in the levels of urinary iAs% and PMI ( P > 0.05). Gender, education level, depth of wells, water arsenic, total number of wells and nail arsenic were the influencing factors of urinary As Ⅲ (β = - 19.82, - 23.83, 0.61, 0.21, 7.26, 2.98, P < 0.05). Age, depth of wells, water arsenic and nail arsenic were the influencing factors of urinary tAs (β = 3.18, 3.25, 1.31, 15.59, P < 0.05). Gender, education level, depth of wells, water arsenic, total number of wells and nail arsenic were the influencing factors of urinary iAs (β = - 20.47, - 25.90, 0.64, 0.25, 7.87, 3.11, P < 0.05). Age, gender, education level, water arsenic and nail arsenic were the influencing factors of urinary MMA V (β = 0.52, - 17.07, - 21.84, 0.22, 2.77, P < 0.05). Age, depth of wells, water arsenic and nail arsenic were the influencing factors of urinary DMA V (β = 2.35, 2.47, 0.85, 9.22, P < 0.05). Conclusions:Compared with healthy individuals, there are differences in arsenic metabolism pattern among individuals with drinking-water-borne arsenic poisoning. Age, gender, education level, depth of wells, water arsenic, total number of wells and nail arsenic may be influencing factors of different arsenic metabolism patterns.

Objective To investigate the application value of energy spectral CT low energy(keV)targeted reconstruction tech-niques combined with adaptive statistical iterative reconstruction-Veo(ASIR-V)algorithm in lower extremity computed tomography venography(CTV).Methods Forty patients with lower extremity CTV examination were retrospectively selected.Gemstone spec-tral imaging(GSI)mode was used with a transient tube voltage of 80 kVp/140 kVp and tube current in GSI Assist mode.Group A(conventional group):70 keV combined with 40％ASIR-V mono-energy images,conventional display field of view(DFOV)inclu-ding both lower extremity.Group B(low keV group):50 keV combined with 50％ASIR-V mono-energy images,DFOV as in group A.Group C(low keV targeted reconstruction group):50 keV combined with 50％to 80％ASIR-V mono-energy images(10％interval,called as groups C1-C4),targeted reconstruction(small DFOV,covered one lower extremity with left and right femurs as the center).The CT and standard deviation(SD)values of the bilateral lower extremity veins were measured on each axial image and the signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)were calculated.Two observers scored the venous images and the sharpness of embolus display subjectively using a 5-point scale and Kappa test was used to examine the consistency.Results In terms of vein dis-play,the score of groups B and C was better than that of group A(P＜0.05).In terms of embolus display sharpness,the scores of large and small embolus in group C increased with the increase of ASIR-V percentage initially and then gradually decreased(P＜0.05).The scores in group C2 were the highest which were superior to the scores of group B and group A(P＜0.05).The CT values of each venous segment in groups B and C were higher than those in group A(P＜0.05).In groups C1 to C4,with the increasing weight of ASIR-V,the SNR and CNR increased gradually(P＜0.05),but slightly lower than those in group B(P＜0.05).Conclusion 50 keV targeted reconstruction techniques combined with 60％ASIR-V algorithm significantly improves the contrast of lower extremity veins and the embolus display sharpness,providing more accurate clinical imaging information.

Objective To explore the application value of deep learning image reconstruction(DLIR)algorithm in low-dose deep inferior epigastric artery(DIEA)computed tomography angiography(CTA).Methods A total of 59 patients undergoing DIEA CTA were prospectively selected and randomly divided into two groups:group A(29 cases)and group B(30 cases).Group A was the conventional radiation dose group(tube voltage 120 kVp),the tube current was dose modulation 3,and the iterative reconstruction algo-rithm was Karl 5.Group B was the low radiation dose group(tube voltage 120 kVp),the tube current was dose modulation 2,with DLIR reconstruction algorithm,and four levels of DLIR(1-4)were reconstructed and labeled as groups B1 to B4.The mean tube current,vol-ume CT dose index(CTDIvol),and dose length product(DLP)of group A and group B were recorded,and the effective dose(ED)was calculated.The CT and standard deviation(SD)values of the external iliac artery and psoas major muscle were measured on axial images of each group,and signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)were calculated.Two observers using double-blind method independently evaluated the DIEA on volume rendering(VR)and maximum intensity projection(MIP)images of each group using a 3-point scale,and a 5-point scale was used to evaluate the overall image quality on axial images.Results Compared with group A,the mean tube current and ED in group B were decreased by 39.33％and 44.09％,respectively(P＜0.05).With the increasing of DLIR level from groups B1 to B4,the SD value of the image gradually decreased,while SNR and CNR gradually increased(P＜0.05).The CNR in groups B3 and B4 was higher than that in group A(P＜0.05).The subjective scores of the two observers were consistent(Kappa value 0.779-0.889,P＜0.05),and there was no statistical significance between group A and group B in the perforating vessels from the DIEA,intramuscular course,and the point of emergence(P＞0.05).With the increase in DLIR level,the subjective score of the overall image quality from group B1 to group B4 showed a trend of first increasing and then decreasing,and the score of group B3 was the highest(4.50±0.51)points,which had no statistical significance compared with group A(4.45±0.51)points(P＞0.05).Conclusion DLIR can effectively reduce the radiation dose of the DIEA CT A scan and ensure the image quality,among which DLIR 3 is the recommended best reconstruction grade.

Objective To explore the effect of large reconstruction matrix(1 024× 1 024)combined with Karl iterative recon-struction algorithm on adrenal gland image quality and auto-segmentation in CT images.Methods Retrospective analysis was per-formed on 40 patients with adrenal gland CT enhancement.After scanning,the original data of venous phase images were reconstruc-ted and grouped.Group A was reconstructed using conventional 512X512 matrix combined with Karl 5;group B was reconstructed using 1 024X1 024 reconstruction matrix combined with Karl iterative reconstruction algorithm(level 5,7,9)of different levels,and was denoted as group B1-B3.Two radiologists assessed the display of adrenal glands,overall image quality,and auto-segmentation stability on a 5-point scale.The CT and standard deviation(SD)values of the adrenal gland and inferior vena cava in each group were measured.The signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)were calculated.The deep learning(DL)-based organ segmentation model was used to segment the adrenal glands of each group of reconstructed images.The Dice coefficients and the vol-ume difference rates were calculated.Results In terms of the display of adrenal glands,overall image quality,and auto-segmentation stability,group B2 had the highest score and was better than group A(P＜0.05).With the increase of Karl levels,the SD values of adrenal gland and inferior vena cava in group B gradually decreased(P＜0.05),SNR and CNR gradually increased(P＜0.05),and there was no significant difference between group B2 and group A in SD value,SNR and CNR(P＞0.05).Dice coefficients of all groups＞0.90.The volume difference rate of adrenal gland(both sides)in group B was less than 5％,which was lower than that in group A(P＜0.05).Conclusion The use of a 1 024 × 1 024 reconstruction matrix combined with Karl 7 is able to optimize the qual-ity of the adrenal gland images without compromising the segmentation accuracy of the adrenal gland images.