ObjectiveThis paper aims to investigate the effects of icariin on spermatogenesis in mice with exercise-induced fatigue and explore the underlying mechanisms. MethodsICR male mice were screened by swimming and randomly divided into normal group， model group， vitamin C group， icariin groups with low， medium， and high doses， and medium-dose icariin+N-nitro-L-arginine methyl ester （L-NAME） group， with 10 mice per group. Except for the normal group， all the other groups underwent weighted swimming training to establish an exercise-induced fatigue model. No gavage was administered during the first two weeks of the weighted training. From week three to four， the icariin groups with low， medium， and high doses received 0.03， 0.06， and 0.12 g·kg^-1 icariin via gavage， respectively. The vitamin C group received 0.2 g·kg^-1 vitamin C. The L-NAME group received 0.06 g·kg^-1 icariin and 0.01 g·kg^-1 L-NAME via intraperitoneal injection. The normal and model groups received equivalent physiological saline. After the experiment， body weight and the last exhaustive swimming time were recorded. Blood urea nitrogen （BUN）， lactate （LA）， lactate dehydrogenase （LDH）， malondialdehyde （MDA）， testicular testosterone （T）， testicular Ca²⁺/Mg²⁺-adenosine triphosphatase （ATPase） （micro-assay）， and the levels of testicular cyclic guanosine monophosphate （cGMP） were measured by using kits. Sperm CD46 levels were detected by flow cytometry. Testicular seminiferous tubules were observed via hematoxylin-eosin （HE） staining， and the testicular morphometric score （TMS） was used to evaluate the spermatogenic function. Protein expression of regucalcin （RGN， SMP30）， cGMP-dependent protein kinase 1 （PKG）， and cGMP-dependent protein kinase anchoring protein （GKAP1） was detected by Western blot. Testicular regucalcin expression was examined by immunofluorescence （IF）. The epididymal sperm quality of mice was observed under a microscope. Fluorescence-stained sections of stimulated by retinoic acid gene 8 （STRA8）， synaptonemal complex protein 3 （SCP3）， and transition protein 1（TNP1） in testicular seminiferous tubules were assessed by immunohistochemistry （IHC）. ResultsCompared with the normal group， the model group showed decreased body weight and exhaustive swimming time （P<0.01）， significantly increased fatigue markers （LA， LDH， and BUN） and lipid peroxidation product MDA （P<0.01）， reduced testicular RGN， PKG， GKAP1， testosterone， Ca²⁺/Mg²⁺-ATPase， and cGMP levels （P<0.01）， decreased sperm motility， sperm count， and TMS scores， and downregulated the expression of STRA8， SCP3， and TNP1. Compared with the model group， the icariin group with high dose exhibited increased exhaustive swimming time （P<0.01）， reduced LA， LDH， BUN， and MDA levels （P<0.01）， elevated superoxide dismutase （SOD） （P<0.01）， upregulated testicular RGN， PKG， GKAP1， testosterone， Ca²⁺/Mg²⁺-ATPase， and cGMP levels （P<0.01）， improved sperm motility， sperm count， and TMS scores， and enhanced STRA8， SCP3， and TNP1 expression. Compared with the L-NAME group， the icariin group with medium dose showed increased expression of STRA8， SCP3， and TNP1 in the testicular tissue （P<0.01） and elevated cGMP and GKAP1 levels （P<0.01）. ConclusionExercise-induced fatigue reduces the expression of RGN and cGMP/PKG/GKAP1 in mice， thereby causing abnormal spermatogenesis and impairing reproductive function in mice. Icariin ameliorates spermatogenic dysfunction in exercise-induced fatigue mice by promoting the expression of RGN and cGMP/PKG/GKAP1， thereby mitigating the damage of exercise-induced fatigue to the reproductive system.

ObjectiveThis paper aims to investigate the effects of icariin on spermatogenesis in mice with exercise-induced fatigue and explore the underlying mechanisms. MethodsICR male mice were screened by swimming and randomly divided into normal group， model group， vitamin C group， icariin groups with low， medium， and high doses， and medium-dose icariin+N-nitro-L-arginine methyl ester （L-NAME） group， with 10 mice per group. Except for the normal group， all the other groups underwent weighted swimming training to establish an exercise-induced fatigue model. No gavage was administered during the first two weeks of the weighted training. From week three to four， the icariin groups with low， medium， and high doses received 0.03， 0.06， and 0.12 g·kg^-1 icariin via gavage， respectively. The vitamin C group received 0.2 g·kg^-1 vitamin C. The L-NAME group received 0.06 g·kg^-1 icariin and 0.01 g·kg^-1 L-NAME via intraperitoneal injection. The normal and model groups received equivalent physiological saline. After the experiment， body weight and the last exhaustive swimming time were recorded. Blood urea nitrogen （BUN）， lactate （LA）， lactate dehydrogenase （LDH）， malondialdehyde （MDA）， testicular testosterone （T）， testicular Ca²⁺/Mg²⁺-adenosine triphosphatase （ATPase） （micro-assay）， and the levels of testicular cyclic guanosine monophosphate （cGMP） were measured by using kits. Sperm CD46 levels were detected by flow cytometry. Testicular seminiferous tubules were observed via hematoxylin-eosin （HE） staining， and the testicular morphometric score （TMS） was used to evaluate the spermatogenic function. Protein expression of regucalcin （RGN， SMP30）， cGMP-dependent protein kinase 1 （PKG）， and cGMP-dependent protein kinase anchoring protein （GKAP1） was detected by Western blot. Testicular regucalcin expression was examined by immunofluorescence （IF）. The epididymal sperm quality of mice was observed under a microscope. Fluorescence-stained sections of stimulated by retinoic acid gene 8 （STRA8）， synaptonemal complex protein 3 （SCP3）， and transition protein 1（TNP1） in testicular seminiferous tubules were assessed by immunohistochemistry （IHC）. ResultsCompared with the normal group， the model group showed decreased body weight and exhaustive swimming time （P<0.01）， significantly increased fatigue markers （LA， LDH， and BUN） and lipid peroxidation product MDA （P<0.01）， reduced testicular RGN， PKG， GKAP1， testosterone， Ca²⁺/Mg²⁺-ATPase， and cGMP levels （P<0.01）， decreased sperm motility， sperm count， and TMS scores， and downregulated the expression of STRA8， SCP3， and TNP1. Compared with the model group， the icariin group with high dose exhibited increased exhaustive swimming time （P<0.01）， reduced LA， LDH， BUN， and MDA levels （P<0.01）， elevated superoxide dismutase （SOD） （P<0.01）， upregulated testicular RGN， PKG， GKAP1， testosterone， Ca²⁺/Mg²⁺-ATPase， and cGMP levels （P<0.01）， improved sperm motility， sperm count， and TMS scores， and enhanced STRA8， SCP3， and TNP1 expression. Compared with the L-NAME group， the icariin group with medium dose showed increased expression of STRA8， SCP3， and TNP1 in the testicular tissue （P<0.01） and elevated cGMP and GKAP1 levels （P<0.01）. ConclusionExercise-induced fatigue reduces the expression of RGN and cGMP/PKG/GKAP1 in mice， thereby causing abnormal spermatogenesis and impairing reproductive function in mice. Icariin ameliorates spermatogenic dysfunction in exercise-induced fatigue mice by promoting the expression of RGN and cGMP/PKG/GKAP1， thereby mitigating the damage of exercise-induced fatigue to the reproductive system.

The Peking Union Medical College School of Nursing has been dedicated to exploring the education of undergraduate students specializing in geriatric nursing since 2016. Through seven years of exploration and practice, aiming at the pain points and difficulties in the process of cultivating geriatric nursing students, the teaching team has developed a progressive and modular curriculum system, with the goal of training geriatric nursing professionals with specialized knowledge and practical innovation abilities, on the platform of a seamless teaching practice base connecting settings from laboratory to community/elderly care institutions/hospital to society, with an emphasis on the integration of ideological and political education with geriatric nursing education. Moreover, a specialized faculty team has been established. This course serves as a model for nurturing excellent nursing professionals possessing the right values and outlook on life as well as ability to cope with the national challenges posed by aging populations.

Objective To understand the changing distribution and antimicrobial resistance profiles of Proteus,Morganella and Providencia in hospitals across China from January 1,2015 to December 31,2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods Antimicrobial susceptibility testing was carried out following the unified CHINET protocol.The results were interpreted in accordance with the breakpoints in the 2021 Clinical & Laboratory Standards Institute(CLSI)M100(31 st Edition).Results A total of 32 433 Enterobacterales strains were isolated during the 7-year period,including 24 160 strains of Proteus,6 704 strains of Morganella,and 1 569 strains of Providencia.The overall number of these Enterobacterales isolates increased significantly over the 7-year period.The top 3 specimen source of these strains were urine,lower respiratory tract specimens,and wound secretions.Proteus,Morganella,and Providencia isolates showed lower resistance rates to amikacin,meropenem,cefoxitin,cefepime,cefoperazone-sulbactam,and piperacillin-tazobactam.For most of the antibiotics tested,less than 10％of the Proteus and Morganella strains were resistant,while less than 20％of the Providencia strains were resistant.The prevalence of carbapenem-resistant Enterobacterales(CRE)was 1.4％in Proteus isolates,1.9％in Morganella isolates,and 15.6％in Providencia isolates.Conclusions The overall number of clinical isolates of Proteus,Morganella and Providencia increased significantly in the 7-year period from 2015 to 2021.The prevalence of CRE strains also increased.More attention should be paid to antimicrobial resistance surveillance and rational antibiotic use so as to prevent the emergence and increase of antimicrobial resistance.

Human adenovirus pneumonia(adenovirus pneumonia for short)is one of the important types of community-acquired pneumonia in children.Severe pneumonia can easily occur in infants or patients with impaired immune function, which can lead to acute lung injury and pulmonary sequelae.In severe infection, the significant imbalance between inflammatory cells and cytokines leads to tissue damage.In this paper, the classification, structure, infection receptor of human adenovirus and the immunological pathogenesis of adenovirus pneumonia are described.

Since its founding 100 years ago, the Communist Party of China (CPC) has attached great importance to the occupational health of workers, and closely linked the safeguard of occupational safety and health of workers with the missions of leading the people to stand up, get rich, and become strong. Based on this, the achievements of occupational health work made under the leadership of the CPC since the new democratic revolution, socialist revolution and construction, the new period of reform and opening up and socialist modernization, and socialism with Chinese characteristics for a new era were summarized, so as to provide reference for understanding the legacy of China's occupational health undertaking, and innovating to create the future.

Pneumoconiosis is a serious occupational disease with the largest number of patients in China. Social security provides strong support for the treatment of pneumoconiosis patients, but there are few reports on the implementation of social security for pneumoconiosis in China. Through literature review, this paper systematically combs the relevant reports of pneumoconiosis social security, understands the current situation and problems of social security for pneumoconiosis in China, and provides a scientific basis for improving security policy for the pneumoconiosis patient.

Pneumoconiosis is a serious occupational disease with the largest number of patients in China. Social security provides strong support for the treatment of pneumoconiosis patients, but there are few reports on the implementation of social security for pneumoconiosis in China. Through literature review, this paper systematically combs the relevant reports of pneumoconiosis social security, understands the current situation and problems of social security for pneumoconiosis in China, and provides a scientific basis for improving security policy for the pneumoconiosis patient.

As an emerging material with excellent property, nanoparticle has been widely used in multiple fields such as chemical industry, textile, biomedicine, etc., which has caused widespread concern about its potential toxicity in society. Due to the limitations of traditional toxicology technology, the high-throughput methods were urgently needed to assess the potential toxicity of particles at nanoparticle size systematically. Metabolomics has been recognized as an emerging omics technology developed by multidisciplinary combination of modern analytical techniques, biochemistry and bioinformatics, which has been widely used to screened early toxicity potential markers and metabolic pathway by analyzing changes in the types and quantities of metabolites in biological samples such as cells and tissues. This article reviewed the progress and challenges of metabolomics in nanotoxicology research.

With the wide application of nanomaterials in consumer products in the market, it is necessary to understand the existence and release of nanomaterials in consumer products, as well as the current situation of exposure assessment of consumers. China has been a large industrial producer with a huge consumer market, but the supervision of consumer goods with nanomaterials is almost blank. This article summarized and classified the existing consumer products of nanomaterials in the international market, and discussed the release of key nanomaterials in consumer products and the exposure assessment methods of consumers, in order to provide a scientific basis for the establishment of a regulatory system for consumer products of nanomaterials in China in the future.