Objective To establish a monkey model of muscle atrophy by fixing the right lower limb and set up e-valuation criteria for that model. Methods Twelve healthy,6-7 year old male cynomolgus monkeys(body weight 6-7 kg)were used in this study. All animals were normal and had no malformed lower limb bones. Right lower limbs of the an-imals were fixed with fiberglass bandage(from knee joint to anklebone)for 15 weeks. Body weight,crus perimeter and crus volume were recorded every two weeks. MRI examinations of the gastrocnemius muscle were conducted at weeks 11,13 and 15. Muscle biopsy was taken for pathological examination at week 15. Results There were no obvious changes of body weight during the experiment. At 15 weeks after modeling,the right crus perimeter and crus volume of the experimental an-imals were significantly decreased(P <0.05),and some biochemical indexes such as serum creatinine,gloucose and al-kaline phosphatase were significantly decreased(P <0.05), while cholesterol was significantly increased(P <0.05).MRI showed atrophy of the right gastrocnemius muscle. Muscle biopsy also showed muscle atrophy and muscle fibers be-came thinner in the right gastrocnemius,and the cross-section area of the muscle fibers was significantly decreased. Con?clusions It is easy to operate and establish a muscle atrophy model in Cynomolgus monkeys by fixing the right lower limb. This model is suitable for objective and easy evaluation of muscle atrophy by measurement of crus perimeter and crus volume of the limb,blood biochemical parameters,MRI examination,and histopathological examination in combination.

Objective To summarize the clinical features,diagnosis and treatment and prognosis of trocar site hernia(TSH).Methods Clinical data of 12 patients with TSH receiving laparoscopic surgery from January 2019 to January 2023 were retrospectively analyzed.The clinical manifestations included intestinal obstruction in 8 cases,trocar incision prolongation with fluid seepage in 1 case,and no obvious symptoms in 3 cases.The patients were diagnosed by abdominal CT in 9 cases,by small intestine contrast imaging in 1 case,by abdominal MRI in 1 case,and by abdominal plain film combined with abdominal color ultrasound in 1 case.The hernia was located in the right lower abdomen in 5 cases,the left lower abdomen in 4 cases,and the right upper abdomen in 3 cases.The trocar diameter was 12 mm in 6 cases,10 mm in 5 cases,and 5 mm in 1 case.A drainage tube was placed at trocar site in 5 cases.Open operations were performed in 11 cases,including small intestine reduction and abdominal wall layer-by-layer suture in 4 cases,partial small intestine resection and anastomosis in 3 cases,Onlay repair in 3 cases,and partial omentectomy,transverse colon reduction and Onlay repair in 1 case.Another case developed trocar site refractoriness which did not heal,and the patient refused surgery,who was given dynamic observation.Results The operation was successful in the 11 cases.Postoperatively,1 case of inflammatory intestinal obstruction underwent intestinal decompression tube implantation,1 case of incision bleeding underwent emergency operation again to stop bleeding,and the rest recovered smoothly.All the 12 patients were followed up for 5-48 months,with a median of 13 months.The patient without surgery had persistent induration and intermittent exudation at the trocar site.One case died due to tumor metastasis,and none of the others had hernia recurrence.Conclusions The most common manifestation of TSH is intestinal obstruction,which mostly occurs at trocar with diameter≥10 mm.If there are symptoms,it should be treated by surgery as soon as possible.

Objective:To estimate the burden of hip fractures and related factors among the Chinese middle-aged and elderly population.Methods:Based on the data of China Health and Retirement Longitudinal Study (CHARLS) in 2015, the burden of hip fractures among Chinese middle-aged and elderly population was evaluated as the years lived with disability (YLD) rate. The relationship between gender, age (45-49, 50-59, 60-69 and ≥70 years old), educational level (no education, elementary school, junior high school, high school and above), region (urban, rural), gross domestic production (GDP) per capita (low, medium and high) and geographic area (northern, eastern, south-central, northwest and southwest regions) and the YLD rate of hip fractures were analyzed, respectively.Results:Excluding items with missing basic information and hip fracture data, a total of 17,830 subjects (8,405 males and 9,425 females) were included in the study with average age 61.6±9.8 years (range 45 to 105 years). The average age in male was 61.9±9.6 years, and that in female was 61.2±10.1 years. The prevalence of hip fractures was 2.3% (410/17,830). The total YLD rate was [694/100,000 (95% Uncertainty Interval ( UI): 462/100,000, 989/100,000)]. The YLD rates were similar between male [693/100,000 (95% UI: 461/100,000, 988/100,000)] and female [696/100,000 (95% UI: 463/100,000, 992/100,000)] subgroups. The YLD rate of hip fractures was increasing with age, which reached at maximum of 1,155/100,000 (95% UI: 769/100,000, 1,646/100,000) for participants aged 70 years or above. The rate was gradually decreased with the upgrade of the educational level. The participants with high school education and above reached the lowest of 434/100,000 (95% UI: 289/100,000, 619/100,000). In addition, the YLD rate of hip fractures in rural areas [721/100,000 (95% UI: 480/100,000, 1,027/100,000)] was higher than that in urban areas [650/100,000 (95% UI: 433/100,000, 926/100,000)]. The YLD rate in areas with higher GDP per capita [545/100,000 (95% UI: 363/100,000, 777/100,000)] was lower than that in areas with lower GDP per capita [761/100,000 (95% UI: 506/100,000, 1,084/100,000)]. Moreover, the participants living in the Northwest region were with the highest YLD rate of hip fractures [1,056/100,000 (95% UI: 703/100,000, 1,506/100,000)], followed by the Southwest region [887/100,000 (95% UI: 590/ 100,000, 1,264/100,000)] and the Northeast region [317/100,000 (95% UI: 211/100,000, 452/100,000)]. Conclusion:Hip fractures exerted heavy burdens on the Chinese middle-aged and elderly population. The YLD rate of hip fractures varied according to geographical regions, greater age, rural areas, low educational levels and low GDP per capita. These related factors could affect the disease burden of hip fractures in China.

Objective:The distribution characteristics of intrathecal drugs and the limitation of current catheterization techniques make traditional intrathecal analgesic treatment nearly useless for refractory craniofacial pain,such as trigemina neuralgia.This technical guideline aims to promote the widespread and standardize the application of intra-prepontine cisternal drug delivery via spinal puncture and catheterization. Methods:A modified Delphi approach was used to work for this guideline.On the issues related to the intra-prepontine cisternal targeted drug delivery technique,the working group consulted 10 experts from the field with 3 rounds of email feedback and 3 rounds of conference discussion. Results:For the efficacy and safety of the intra-prepontine cisternal targeted drug delivery technique,a consensus was formed on 7 topics(with an agreement rate of more than 80%),including the principles of the technique,indications and contraindications,patient preparation,surgical specifications for intra-prepontine cisternal catheter placement,analgesic dosage coordination,analgesic management,and prevention and treatment of complications. Conclusion:Utilizing the intra-prepontine cisternal drug infusion system to manage refractory craniofacial pain could provide advantages in terms of minimally invasive,secure,and effective treatment.This application can not only alleviate the suffering of individuals experiencing the prolonged pain but also support the maintenance of quality of life and dignity in their final moments,justifiing its widespread dissemination and standardized adoption in domestic and international professional fields.

Objective:To provide evidence-based recommendations for the prevention and management of lower limb ischemia in veno-arterial extracorporeal membrane oxygenation (VA-ECMO) patients during treatment according to search, evaluate, and summarize the best evidence on the prevention and management of lower limb ischemia in patients with VA-ECMO.Methods:Based on the PIPOST framework (population, intervention, professional, outcome, setting, and type of evidence), an evidence-based question was formulated. A systematic search was conducted according to the "6S" evidence pyramid model in both domestic and international databases, as well as professional association websites, for all evidence related to the prevention and management of lower limb ischemia in VA-ECMO patients (aged ≥18 years). The types of evidence included clinical decisions, guidelines, expert consensus, systematic reviews, evidence summaries, and original studies. The search was conducted from the construction of the databases to February 2024. Two researchers independently conducted a literature quality evaluation, extracted and summarized evidence from the studies that met the quality criteria.Results:A total of 13 articles were included, consisting of 3 clinical decisions, 3 guidelines, 3 expert consensus, 3 systematic reviews, and 1 randomized controlled trial. A total of 18 pieces of evidence in 7 dimensions were summarized, including risk factors of VA-ECMO lower limb ischemia, evaluation before catheterization, evaluation and monitoring during treatment, prevention of lower limb ischemia, treatment of lower limb ischemia, management of distal perfusion catheter (DPC), and monitoring after VA-ECMO weaning.Conclusion:This evidence summary provides evidence-based recommendations for the prevention and management of lower limb ischemia in VA-ECMO patients, aiming to assist clinical healthcare professionals in developing tailored strategies for the prevention and management of lower limb ischemia based on during VA-ECMO support.

The investigation of environmental radioactivity level is an important basic work of ecological environment protection. It can provide basic data and scientific basis for the evaluation of radioactive environment quality and the formulation of radiation safety regulations and standards. Based on many years of practical experience of environmental radioactivity level investigation, combined with relevant regulations and standards, this paper summarizes the common investigation methods in the investigation and research of environmental radioactivity level at home and abroad, summarizes a set of environmental radioactivity level investigation scheme with strong applicability, and gives detailed suggestions on the ideas, methods, technical routes and other key points of the investigation scheme. The research results of this paper can provide a reference for the preparation of environmental radioactive level investigation scheme.

OBJECTIVE To study protective effect and potential mechanism of Modified yupingfeng nasal spray （YPF+） on nasal mucosal injury in allergic rhinitis （AR） model rats. METHODS AR model was induced by ovalbumin （OVA） and randomly divided into model group， YPF+group （50 µg/side，twice a day）， positive control group （Mometasone furoate aqueous nasal spray， 50 µg/side，once a day）； the blank group was set up， with 10 rats in each group. Administration groups were given relevant medicine， and blank group and model group were given equivalent normal saline for consecutive 4 weeks. Thirty minutes after last medication， the behavioral scores of rats were recorded， and the pathological changes of their nasal mucosa tissue were observed. The level of reactive oxygen species （ROS） in nasal mucosa tissue was detected. The protein and mRNA expressions of nucleotide- binding oligomerization domain-like receptor protein 3 （NLRP3），caspase-1，gasdermin D （GSDMD） were detected； the contents of interleukin-1β （IL-1β） and IL-18 in serum were also determined. RESULTS Compared with blank group， in model group， the nasal mucosa tissue structure was disordered， inflammatory cells infiltrated seriously， and lamina propria vascular dilation was visible； its behavioral score and pathological score， the level of ROS， protein and mRNA expressions of NLRP3， caspase-1 and GSDMD， serum contents of IL-1β and IL-18 in nasal mucosa tissue were increased significantly （P＜0.05）. Compared with model group， the symptoms of nasal mucosal injury in rats of each drug group were improved to varying degrees， and the above indicators were significantly reduced （P＜0.05）. CONCLUSIONS YPF+ may improve nasal mucosal injury of rats， relieve AR symptoms such as sneezing， itchy nose， runny nose， the mechanism of which may be associated with reducing the production of ROS in nasal mucosa and downregulating NLRP3/caspase-1/ GSDMD pathway.

OBJECTIVETo fabricate organic-inorganic composite tissue engineering scaffolds for reconstructing calcified cartilage layer based on three-dimensional (3D) printing technique.

METHODSThe scaffolds were developed by 3D-printing technique with highly bioactive calcium-magnesium silicate ultrafine particles of 1%, 3% and 5% of mass fraction, in which the organic phases were composed of type I collagen and sodium hyaluronate. The 3D-printed scaffolds were then crosslinked and solidified by alginate and CaCl₂ aerosol. The pore size and distribution of inorganic phase were observed with scanning electron microscope (SEM); the mechanical properties were tested with universal material testing machine, and the porosity of scaffolds was also measured.

RESULTSPore size was approximately (212.3 ± 34.2) μm with a porosity of (48.3 ± 5.9)%, the compressive modulus of the scaffolds was (7.2 ± 1.2) MPa, which was irrelevant to the percentage changes of calcium-magnesium silicate, the compressive modulus was between that of cartilage and subchondral bone.

CONCLUSIONThe porous scaffolds for calcified cartilage layer have been successfully fabricated, which would be used for multi-layered composite scaffolds in osteochondral injury.

Bioprinting ; Cartilage ; growth & development ; Materials Testing ; Porosity ; Printing, Three-Dimensional ; Tissue Engineering ; methods ; Tissue Scaffolds ; chemistry

METTL3 and METTL14 are two components that form the core heterodimer of the main RNA m6A methyltransferase complex (MTC) that installs m6A. Surprisingly, depletion of METTL3 or METTL14 displayed distinct effects on stemness maintenance of mouse embryonic stem cell (mESC). While comparable global hypo-methylation in RNA m6A was observed in Mettl3 or Mettl14 knockout mESCs, respectively. Mettl14 knockout led to a globally decreased nascent RNA synthesis, whereas Mettl3 depletion resulted in transcription upregulation, suggesting that METTL14 might possess an m6A-independent role in gene regulation. We found that METTL14 colocalizes with the repressive H3K27me3 modification. Mechanistically, METTL14, but not METTL3, binds H3K27me3 and recruits KDM6B to induce H3K27me3 demethylation independent of METTL3. Depletion of METTL14 thus led to a global increase in H3K27me3 level along with a global gene suppression. The effects of METTL14 on regulation of H3K27me3 is essential for the transition from self-renewal to differentiation of mESCs. This work reveals a regulatory mechanism on heterochromatin by METTL14 in a manner distinct from METTL3 and independently of m6A, and critically impacts transcriptional regulation, stemness maintenance, and differentiation of mESCs.
Animals ; Mice ; Methylation ; Chromatin ; Histones/metabolism* ; RNA, Messenger/genetics* ; Methyltransferases/metabolism* ; RNA/metabolism*