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.

Guided by the theory of "mutual dependence of ascending and descending"， recurrent pediatric cough and asthma are considered to result from the imbalance of the ascending and descending of zang-fu organ qi， which is closely associated with deficiency， phlegm， and blood stasis. In clinical practice， the disease is treated based on differentiation during the initial stage， progression stage， and stable stage. In the initial stage， the pathogenesis is attributed to lung deficiency complicated by external pathogens and liver qi rising to attack the lung； the treatment should focus on restraining the lung and calming the liver， using the self-formulated Longchai Yuchuan Fomulation （龙柴愈喘方）. During the progression stage， the disorder is due to the spleen failing to ascend clear qi and the kidney failing to grasp qi， leading to phlegm formation from deficiency； treatment should focus on tonifying spleen yang， supplementing kidney qi， and resolving phlegm and fluid retention， using a modified combination of Linggui Zhugan Decoction （苓桂术甘汤） and Jinkui Shenqi Pill （金匮肾气丸）. In the stable stage， qi deficiency leads to poor consolidation， with phlegm turbidity and blood stasis； the treatment should aim at tonifying qi， transforming phlegm， and dispelling blood stasis， using a modified version of Guizhi Fuling Pill （桂枝茯苓丸）.

Guided by "triple-yang combination of diseases"， it is believed that the core pathogenesis of acute respiratory infection in children is external cold and internal heat， and triple-yang combination， and its transmission can be divided into two forms. First， the taiyang syndrome usually happens earlier， presenting as the exterior cold in taiyang is not yet resolved， and inward penetration of exterior cold transfers into heat， which combines the disease of shaoyang and yangming； second， yangming meridian already has internal heat， then meets with taiyang meridian externally infected with pathogenic qi， both internal and external pathogens accumulated in the two meridians and affected shaoyang meridian. It is proposed that the therapeutic method should release the exterior and clean the interior， and treat the triple-yang at the same time， with self-prescribed Chaige Gaore Formula （柴葛高热方） as the empirical formula for the treatment of acute respiratory infections in children.

Objective:To investigate the clinicopathological and genetic characteristics of malignant transformation of polyostotic fibrous dysplasia (FD) in long bone.Methods:A retrospective analysis of clinical characteristics and morphological features was conducted from 4 cases of malignant transformation of FD diagnosed at Beijing Jishuitan Hospital from January 2016 to December 2023. Hotspot mutations for GNAS gene were tested in 4 cases by Sanger sequencing, in which both FD and malignant tissues were detected in 3 cases respectively.Results:There were 2 female and 2 male patients, aged 46 to 53 years [mean (49±3.2) years], and the course of the disease spanned from 2 months to 36 years. The tumor involved the femur ( n=2), tibia ( n=1) and humerus ( n=1). Three of them were diagnosed with FD before surgery. Single photon emission computed tomography showed multiple increases in bone metabolism, CT showed poorly margin, cortical destruction and soft tissue mass with uneven enhancement. Three cases had both FD and sarcoma components, while the remaining case exhibited exclusively sarcoma. The sarcomas displayed significant morphological variation, with 1 case diagnosed as osteosarcoma and 3 cases classified as low to high grade spindle cell sarcoma. Immunohistochemical results did not provide any indications for clear classification. Sanger sequencing demonstrated GNAS mutations of p.R201H (c.CGT>CAT, n=2) and p.R201C (c.CGT>TGT, n=2). All 4 cases were followed-up for 18 to 76 months, and received chemotherapy after surgery; 2 cases maintained disease-free, one case was diagnosed with invasive breast cancer through a core needle biopsy 3 months after chemotherapy, and another one was found to relapse 18 months after surgery. Conclusions:Some cases of polyostotic FD occur in association with café-au-lait macules and/or endocrine hyperfunctioning in McCune-Albright syndrome (MAS); polyostotic FD and MAS have more malignant potential than monostotic FD, but they are not the risk factors for FD malignancy. GNAS mutations may be involved in the occurrence and development of FD. The histologic types of malignant transformation of polyostotic FD in long bone are diverse, the sarcoma components of FD also present the GNAS mutation, suggesting potential involvement in the pathogenesis of FD malignancy.

Based on the theory of "spleen functions as wei qi"， this paper believes that the disease mechanism of allergic rhinitis （AR） in children is the nasal dysfunction caused by the loss of spleen's wei qi. The root cause of AR is the failure of splenic transportation as well as its inability to properly distribute nutrients. The inducement of AR is the invasion of pathogenic qi coupled with insecurity of the wei exterior. The key to AR recurrence lies in the deficiency of healthy qi and lingering of pathogenic qi， with pathogenic qi lodging inside the body. The treatment should adhere to the principle of helping the spleen restore wei qi. During the acute phase， the treatment should dispel wind， conso-lidate the wei qi， and relieve stuffy orifices， and the modified Qufeng Tongqiao Decoction （祛风通窍汤） is used. During the remission phase， the treatment should fortify the spleen， raise the clear， and harmonize the wei qi， and the modified Yuhan Decoction （御寒汤） is applied. During the recovery phase， the treatment should reinforce the healthy qi， consolidate the constitution， and strengthen the wei qi， and the modified Huangqi Jianzhong Decoction （黄芪建中汤） is employed.

Based on the "sweat pore-qi and liquid-collaterals" theory， it is considered that the core pathogenesis of pediatric infectious mononucleosis lies in the obstruction of sweat pores， the failure of qi and liquid to disperse， and damage to the collaterals due to pathogenic toxins. Accordingly， the treatment principles proposed include unblocking the sweat pores， regulating qi and liquid， and smoothing the collaterals. In clinical practice， treatment is differentiated according to stages： initial， acute， and late stages. In the initial stage， invasion of warm pathogenic toxins into the lung defense leads to obstruction of the sweat pores， which should be treated by unblocking the sweat pores and expelling pathogens outward. In the acute stage， the obstruction of the sweat pores worsens， leading to the failure of qi and liquid dispersal， resulting in intense heat toxins with accumulation of dampness， phlegm， and blood stasis， which should be treated by promoting qi movement， resolving dampness and phlegm， clearing heat， detoxifying， and dispersing stasis to regulate qi and liquid. In the late stage， residual pathogens remain， with qi and yin deficiency and unsmooth collaterals， which should be treated by unblocking the collaterals， dissipating nodules， tonifying qi， and nourishing yin to smooth the collaterals. This approach may provide new insights for the clinical treatment of pediatric infectious mononucleosis.

Objective:To investigate the clinicopathological and genetic characteristics of malignant transformation of polyostotic fibrous dysplasia (FD) in long bone.Methods:A retrospective analysis of clinical characteristics and morphological features was conducted from 4 cases of malignant transformation of FD diagnosed at Beijing Jishuitan Hospital from January 2016 to December 2023. Hotspot mutations for GNAS gene were tested in 4 cases by Sanger sequencing, in which both FD and malignant tissues were detected in 3 cases respectively.Results:There were 2 female and 2 male patients, aged 46 to 53 years [mean (49±3.2) years], and the course of the disease spanned from 2 months to 36 years. The tumor involved the femur ( n=2), tibia ( n=1) and humerus ( n=1). Three of them were diagnosed with FD before surgery. Single photon emission computed tomography showed multiple increases in bone metabolism, CT showed poorly margin, cortical destruction and soft tissue mass with uneven enhancement. Three cases had both FD and sarcoma components, while the remaining case exhibited exclusively sarcoma. The sarcomas displayed significant morphological variation, with 1 case diagnosed as osteosarcoma and 3 cases classified as low to high grade spindle cell sarcoma. Immunohistochemical results did not provide any indications for clear classification. Sanger sequencing demonstrated GNAS mutations of p.R201H (c.CGT>CAT, n=2) and p.R201C (c.CGT>TGT, n=2). All 4 cases were followed-up for 18 to 76 months, and received chemotherapy after surgery; 2 cases maintained disease-free, one case was diagnosed with invasive breast cancer through a core needle biopsy 3 months after chemotherapy, and another one was found to relapse 18 months after surgery. Conclusions:Some cases of polyostotic FD occur in association with café-au-lait macules and/or endocrine hyperfunctioning in McCune-Albright syndrome (MAS); polyostotic FD and MAS have more malignant potential than monostotic FD, but they are not the risk factors for FD malignancy. GNAS mutations may be involved in the occurrence and development of FD. The histologic types of malignant transformation of polyostotic FD in long bone are diverse, the sarcoma components of FD also present the GNAS mutation, suggesting potential involvement in the pathogenesis of FD malignancy.

Objective: To evaluate the bone repair effect of 3D-printed magnesium (Mg)-loaded polycaprolactone (PCL) scaffolds in a rat skull defect model. Methods: PCL scaffolds mixed with Mg microparticles were prepared by using 3D printing technology, as were pure PCL scaffolds. The surface morphologies of the two scaffolds were observed by scanning electron microscopy (SEM), and the surface elemental composition was analyzed via energy dispersive spectroscopy (EDS). The physical properties of the scaffolds were characterized through contact angle measurements and an electronic universal testing machine. This study has been reviewed and approved by the Ethics Committee. A critical size defect model was established in the skull of 15 Sprague-Dawley (SD) rats, which were divided into the PCL group, PCL-Mg group, and untreated group, with 5 rats in each group. Micro-CT scanning was performed to detect and analyze skull defect healing at 4 and 8 weeks after surgery, and samples from the skull defect area and major organs of the rats were obtained for histological staining at 8 weeks after surgery. Results: The scaffolds had a pore size of (480 ± 25) μm, a fiber diameter of (300 ± 25) μm, and a porosity of approximately 66%. The PCL-Mg scaffolds contained 1.0 At% Mg, indicating successful incorporation of Mg microparticles. The contact angle of the PCL-Mg scaffolds was 68.97° ± 1.39°, indicating improved wettability compared to that of pure PCL scaffolds. Additionally, compared with that of pure PCL scaffolds, the compressive modulus of the PCL-Mg scaffolds was (57.37 ± 8.33) MPa, demonstrating enhanced strength. The PCL-Mg group exhibited the best bone formation behavior in the skull defect area compared with the control group and PCL group at 4 and 8 weeks after surgery. Moreover, quantitative parameters, such as bone volume (BV), bone volume/total volume (BV/TV), bone surface (BS), bone surface/total volume (BS/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N) and bone mineral density (BMD), of skull defects were better than those in the other groups, indicating the best bone regeneration effect. H&E, Goldner, and VG staining revealed more mineralized new bone formation in the PCL-Mg group than in the other groups, and H&E staining of the major organs revealed good biosafety of the material. Conclusion PCL-Mg scaffolds can promote the repair of bone defects and have clinical potential as a new scaffold material for the repair of maxillofacial bone defects.

Objective:To investigate the diagnostic value of detecting MDM2 gene amplification by fluorescence in situ hybridization (FISH) in low-grade osteosarcoma (LGOS).Methods:Thirty cases of parosteal osteosarcoma (POS) and 14 cases of low-grade central osteosarcoma (LGCOS) from April 2009 to August 2022 at Beijing Jishuitan Hospital, Capital Medical University were analyzed for the presence of MDM2 gene amplification by FISH. Fifty-eight additional cases were used as negative controls (including 28 cases of fibrous dysplasia, 5 cases of giant cell tumor, 4 cases of conventional osteosarcoma, 2 cases each of periosteal osteosarcoma, reparative changes after fracture, pleomorphic undifferentiated sarcoma, low grade myofibroblastic sarcoma, fibrous dysplasia with malignant transformation, one case each of leiomyosarcoma, sclerosing epithelioid fibrosarcoma, malignant peripheral nerve sheath tumor, desmoplastic fibroma of bone, solitary fibrous tumor, aneurysmal bone cyst, clear cell chondrosarcoma, osteofibrous dysplasia, and 3 cases of unclassified spindle cell tumor).Results:Among the 30 patients with POS, 15 were male and 15 were female, ranging in age from 10 to 59 years (mean 35 years, median 30.5 years). Among the 14 patients with LGCOS, four were male and 10 were female, ranging in age from 15 to 56 years (mean 37 years, median 36 years). All except one case were successfully detected by FISH. MDM2 gene amplification was detected in 27 cases of POS (27/29,91.3%) and 8 cases of LGCOS (8/14). All the negative controls were negative for MDM2 gene amplification. The positive rate of MDM2 gene amplification was significantly different between the case group and the control group ( P<0.05). The sensitivity and specificity of MDM2 gene amplification in diagnosing POS and LGCOS were 91.3% and 100.0%; and 57.1% and 100.0%, respectively. The sensitivity and specificity of MDM2 gene amplification in diagnosing LGOS (including POS and LGCOS) were 81.3% and 100.0%, respectively. In cases where MDM2 gene was amplified, the MDM2 amplified signal was clustered. Nine cases showed increased CEP12 signal different from polyploidy which was displayed as small and weak signal points or cloud flocculent and cluster signals. Conclusions:Detection of MDM2 gene amplification by FISH is a highly sensitive and specific marker for LGOS. The interpretation criteria for FISH detection of MDM2 amplification are currently not unified. The signal characteristics need more attention when interpreting.

Objective To investigate the osteogenic properties of a methacrylated gelatin(GelMA)/bone marrow mesenchymal stem cells(BMSCs)composite hydrogel applied to the skull defect area of rats and to provide an experi-mental basis for the development of bone regeneration biomaterials.Methods This study was approved by the Animal Ethics Committee of Nanjing University.A novel photocurable composite biohydrogel was developed by constructing photoinitiators[lthium phenyl(2,4,6-trimethylbenzoyl)phosphinate,LAP],GelMA,and BMSCs.The surface morphology and elemental composition of the gel were examined using scanning electron microscopy(SEM)and energy-dispersive X-ray spectroscopy(EDX).The compressive strength of the gel was evaluated using an electronic universal testing ma-chine.After in vitro culture for 1,2,and 5 days,the proliferation of the BMSCs in the hydrogels was assessed using a CCK-8 assay,and their survival and morphology were examined through confocal microscopy.A 5 mm critical bone de-ficiency model was generated in a rat skull.The group receiving composite hydrogel treatment was referred to as the Gel-MA/BMSCs group,whereas the untreated group served as the control group.At the 4th and 8th weeks,micro-CT scans were taken to measure the bone defect area and new bone index,while at the 8th week,skull samples from the defect ar-ea were subjected to H&E staining,van Gieson staining,and Goldner staining to evaluate the quality of bone regenera-tion and new bone formation.Results SEM observed that the solidified GelMA showed a 3D spongy gel network with uniform morphology,the porosity of GelMA was 73.41％and the pore size of GelMA was(28.75±7.13)μm.EDX results showed that C and O were evenly distributed in the network macroporous structure of hydrogel.The hydrogel compres-sion strength was 152 kPa.On the 5th day of GelMA/BMSCs culture,the cellular morphology transitioned from oval to spindle shaped under microscopic observation,accompanied by a significant increase in cell proliferation(159.4％,as determined by the CCK-8 assay).At 4 weeks after surgery,a 3D reconstructed micro-CT image revealed a minimal re-duction in bone defect size within the control group and abundant new bone formation in the GelMA/BMSCs group.At 8 weeks after surgery,no significant changes were observed in the control group's bone defect area,with only limited evi-dence of new bone growth;however,substantial healing of skull defects was evident in the GelMA/BMSCs group.Quan-titative analysis at both the 4-and 8-week examinations indicated significant improvements in the new bone volume(BV),new bone volume/total bone volume(BV/TV),bone surface(BS),and bone surface/total bone volume(BS/TV)in the GelMA/BMSCs group compared to those in the control group(P＜0.05).Histological staining showed continuous and dense formation of bone tissue within the defects in the GelMA/BMSCs group and only sporadic formation of new bone,primarily consisting of fibrous connective tissue,at the defect edge in the control group.Conclusion Photocur-ing hydrogel-based stem cell therapy exhibits favorable biosafety profiles and has potential for clinical application by inducing new bone formation and promoting maturation within rat skull defects.