1.Research progress on the role and mechanism of high mobility group box protein 1 after spinal cord injury
Xin XUE ; Chang-zheng YIN ; Jin-hui CHEN ; Lu-rong HUANG ; Xin ZHENG ; Yi-min LI ; Guo-bao XIAO ; Ping ZHANG ; Jian-hua ZHAO
Journal of Regional Anatomy and Operative Surgery 2025;34(10):918-923
High mobility group box protein 1(HMGB1)is one of the most widely expressed protein member in the HMGs family,which is well known for its involvement in the body inflammatory response.Previous researches have found that it plays a significant role in cell migration,immune identification and neuroprotection.Spinal cord injury is a disease that causes severe damage to the nervous system,and neural circuits are disrupted after a spinal cord injury,which leads to many conditions including ischemia and hypoxia,inflammatory responses,demyelinating lesions,and glial scar formation that are detrimental to nerve regeneration and repair,making it one of the most difficult diseases to treat in the modern spinal surgery field.HMGB1 is upregulated after spinal cord injury,thereby regulating neuroinflam-matory responses,and participating in the neuronal apoptosis,promoting neuronal regeneration,and inducing neural stem cell differentiation and migration,which plays an important role in the process of neural function recovery.This paper summarizes the structure and function of HMGB1,as well as its role in spinal cord injury,in order to provide direction for founding therapeutic target for neurological function recovery after spinal cord injury.
2.Host MYH9 protein promotes Zika virus invasion in U251 cells
Qianyi PENG ; Yalan FENG ; Jing HE ; Rong HUANG ; Jiafei ZHAN ; Yuhang ZHENG ; Chen CHEN ; Rong XIA ; Lei YUAN ; Jian YANG ; Kui XU
Chinese Journal of Experimental and Clinical Virology 2025;39(3):278-286
Objective:This study aimed to investigate the regulatory role and mechanism of myosin heavy chain 9 (MYH9) in the invasion of Zika virus (ZIKV) into human glioma cells (U251).Methods:Utilizing CRISPR/Cas9 technology, MYH9-knockout U251 cells (U251-MYH9 KD) were constructed. Following ZIKV infection, the protein expression levels, RNA load, and viral titer of ZIKV were detected through western blot (WB), Real-time fluorescence quantitative polymerase chain reaction (qPCR), and plaque formation assays, respectively. The infection efficiency of ZIKV in U251 cells treated with the MYH9 inhibitor blebbistatin was assessed. The binding and internalization efficiency of ZIKV were measured in U251-MYH9 KD cells. The interaction between MYH9 and the ZIKV envelope protein (E) was studied using co-immunoprecipitation (Co-IP). The effects of soluble MYH9 recombinant protein and anti-human MYH9 antibodies on ZIKV infection were evaluated by qPCR and plaque formation assays. Results:It was found that knockout or inhibition of MYH9 significantly suppressed ZIKV infection in U251 cells. MYH9 knockout notably inhibited the binding and internalization of ZIKV in U251 cells. MYH9 interacted with the ZIKV E protein, and both MYH9 recombinant protein and anti-human MYH9 antibodies, by blocking the binding of ZIKV E protein to cell surface MYH9, inhibited ZIKV infection in U251 cells in a dose-dependent manner.Conclusions:MYH9 facilitates ZIKV invasion into U251 cells through interaction with the ZIKV E protein.
3.National bloodstream infection bacterial resistance surveillance report 2023: Gram-positive bacteria
Chaoqun YING ; Jinru JI ; Zhiying LIU ; Qing YANG ; Haishen KONG ; Jiangqin SONG ; Hui DING ; Yanyan LI ; Yuanyuan DAI ; Haifeng MAO ; Pengpeng TIAN ; Lu WANG ; Yongyun LIU ; Yizheng ZHOU ; Jiliang WANG ; Yan JIN ; Donghong HUANG ; Hongyun XU ; Peng ZHANG ; Xinhua QIANG ; Hong HE ; Lin ZHENG ; Junmin CAO ; Zhou LIU ; Ying HUANG ; Yan GENG ; Haiquan KANG ; Dan LIU ; Guolin LIAO ; Lixia ZHANG ; Fenghong CHEN ; Yanhong LI ; Baohua ZHANG ; Haixin DONG ; Xiaoyan LI ; Donghua LIU ; Qiuying ZHANG ; Xuefei HU ; Liang GUO ; Sijin MAN ; Dijing SONG ; Rong XU ; Youdong YIN ; Kunpeng LIANG ; Aiyun LI ; Zhuo LI ; Hongxia HU ; Guoping LU ; Jinhua LIANG ; Qiang LIU ; Yinqiao DONG ; Jilu SHEN ; Shuyan HU ; Liang LUAN ; Jian LI ; Ling MENG ; Dengyan QIAO ; Xiusan XIA ; Bo QUAN ; Dahong WANG ; Chunhua HAN ; Xiaoping YAN ; Fei LI ; Shifu WANG ; Ping SHEN ; Yunbo CHEN ; Yonghong XIAO
Chinese Journal of Clinical Infectious Diseases 2025;18(2):118-132
Objective:To report the nationwide surveillance results of pathogenic profiles and antimicrobial resistance patterns of Gram-positive bloodstream infections in China in 2023.Methods:The clinical isolates of Gram-posttive bacteria from blood cultures were collected in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System(BRICS)during January to December 2023. Antimicrobial susceptibility testing was performed using the dilution method recommended by the Clinical and Laboratory Standards Institute(CLSI). Statistical analyses were conducted using WHONET 5.6 and SPSS 25.0 software.Results:A total of 4 385 Gram-positive bacterial isolates were obtained from 60 participating center. The top five pathogens were Staphylococcus aureus( n=1 544,35.2%),coagulase-negative Staphylococci( n=1 441,32.9%), Enterococcus faecium( n=574,13.1%), Enterococcus faecalis( n=385,8.8%),and α-hemolytic Streptococci( n=187,4.3%). The prevalence of methicillin-resistant Staphylococcus aureus(MRSA)and methicillin-resistant coagulase-negative Staphylococci(MRCNS)was 26.2%(405/1 544)and 69.8%(1 006/1 441),respectively. Notably,all Staphylococci remained susceptible to glycopeptide or daptomycin. Staphylococcus aureus demonstrated excellent susceptibility(>97.0%)to cephalobiol,rifampicin,trimethoprim-sulfamethoxazole,linezolid,minocycline,tigecycline,and eravacycline. No Enterococcus exhibiting resistance to linezolid were detected. Glycopeptide resistance was uncommon but more frequent in Enterococcus faecium(resistance to vancomycin and teicoplanin:both 1.7%)compared to Enterococcus faecalis(both 0.3%). The detection rates of MRSA and MRCNS exhibited significant regional variations across the country( χ2=17.674 and 148.650,respectively,both P<0.001). No vancomycin-resistant Enterococci were detected in central China. Institutional comparison demonstrated higher prevalence of MRSA( χ2=14.111, P<0.001)and MRCNS( χ2=4.828, P=0.028)in provincial hospitals than that in municipal hospitals. Socioeconomic analysis identified elevated detection rates of both MRSA( χ2=18.986, P<0.001)and MRCNS( χ2=4.477, P=0.034)in less developed regions(per capita GDP
4.National bloodstream infection bacterial resistance surveillance report (2023) : Gram-negative bacteria
Jinru JI ; Zhiying LIU ; Chaoqun YING ; Qing YANG ; Haishen KONG ; Jiangqin SONG ; Hui DING ; Yanyan LI ; Yuanyuan DAI ; Haifeng MAO ; Pengpeng TIAN ; Lu WANG ; Yongyun LIU ; Yizheng ZHOU ; Jiliang WANG ; Yan JIN ; Donghong HUANG ; Hongyun XU ; Peng ZHANG ; Xinhua QIANG ; Hong HE ; Lin ZHENG ; Junmin CAO ; Zhou LIU ; Ying HUANG ; Yan GENG ; Haiquan KANG ; Dan LIU ; Guolin LIAO ; Lixia ZHANG ; Fenghong CHEN ; Yanhong LI ; Baohua ZHANG ; Haixin DONG ; Xiaoyan LI ; Donghua LIU ; Qiuying ZHANG ; Xuefei HU ; Liang GUO ; Sijin MAN ; Dijing SONG ; Rong XU ; Youdong YIN ; Kunpeng LIANG ; Aiyun LI ; Zhuo LI ; Hongxia HU ; Guoping LU ; Jinhua LIANG ; Qiang LIU ; Yinqiao DONG ; Jilu SHEN ; Shuyan HU ; Liang LUAN ; Jian LI ; Ling MENG ; Dengyan QIAO ; Xiusan XIA ; Bo QUAN ; Dahong WANG ; Chunhua HAN ; Xiaoping YAN ; Fei LI ; Shifu WANG ; Ping SHEN ; Yunbo CHEN ; Yonghong XIAO
Chinese Journal of Clinical Infectious Diseases 2025;18(1):47-62
Objective:To report the results of bacterial resistant investigation collaborative system(BRICS)on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2023,and provide reference for clinical tretment of bloodstream infections and prevention and control of bacterial resistance.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of BRICS were collected during January 2023 to December 2023. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute(CLSI). WHONET 5.6 and SPSS 25.0 were used to analyze the data.Results:During the study period,11 492 strains of Gram-negative bacteria were collected from 60 hospitals,of which 10 098(87.9%)were Enterobacterales and 1 394(12.1%)were non-fermentative bacteria. The top 5 bacterial species were Escherichia coli(50.0%), Klebsiella pneumoniae(26.1%), Pseudomonas aeruginosa(5.1%), Acinetobacter baumannii complex(5.0%)and Enterobacter cloacae complex(4.1%). The ESBL-producing rates in Escherichia coli, Klebsiella pneumoniae and Proteus mirablilis were 46.8%(2 685/5 741),18.3%(549/2 999)and 44.0%(77/175),respectively. The prevalence of carbapenem-resistant Escherichia coli(CREC)and carbapenem-resistant Klebsiella pneumoniae(CRKP)were 1.3%(76/5 741)and 15.0%(450/2 999);32.9%(25/76)and 78.0%(351/450)of CREC and CRKP were sensitive to ceftazidime/avibactam combination,respectively. 94.7%(72/76)and 90.2%(406/450)of CREC and CRKP were sensitive to aztreonam/avibactam combination. Furthermore,57.9%(44/76)and 79.1%(356/450)were sensitive to imipenem/relebactam combination. The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)complex was 64.6%(370/573),while more than 80.0% of CRAB complex was sensitive to tigecycline,eravacycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa(CRPA)was 17.0%(99/581). There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of important Gram-negative bacteria resistance among different regions in China,with statistically significant differences in the prevalence of CREC,CRKP,CRPA and CRAB complex( χ2=10.6,28.6,10.8 and 19.3, P<0.05). The prevalence of ESBL-producing Escherichia coli, CREC,CRAB complex and CRKP were higher in provincial hospitals than those in municipal hospitals( χ2=12.5,9.8,12.7 and 57.8,all P<0.01). Conclusions:Gram-negative bacteria are the main pathogens causing bloodstream infections in China,and Escherichia coli is ranked in the top,while the trend of Klebsiella pneumoniae increases continuously with time. CRKP infection shows a slow upward trend,CREC infecton maintains a low prevalence level,and CRAB complex infection continues to exhibit a high prevalence rate. The composition and resistance patterns of pathogens causing bloodstream infections vary to some extent across different regions and levels of hospitals in China.
5.Research progress on the role and mechanism of high mobility group box protein 1 after spinal cord injury
Xin XUE ; Chang-zheng YIN ; Jin-hui CHEN ; Lu-rong HUANG ; Xin ZHENG ; Yi-min LI ; Guo-bao XIAO ; Ping ZHANG ; Jian-hua ZHAO
Journal of Regional Anatomy and Operative Surgery 2025;34(10):918-923
High mobility group box protein 1(HMGB1)is one of the most widely expressed protein member in the HMGs family,which is well known for its involvement in the body inflammatory response.Previous researches have found that it plays a significant role in cell migration,immune identification and neuroprotection.Spinal cord injury is a disease that causes severe damage to the nervous system,and neural circuits are disrupted after a spinal cord injury,which leads to many conditions including ischemia and hypoxia,inflammatory responses,demyelinating lesions,and glial scar formation that are detrimental to nerve regeneration and repair,making it one of the most difficult diseases to treat in the modern spinal surgery field.HMGB1 is upregulated after spinal cord injury,thereby regulating neuroinflam-matory responses,and participating in the neuronal apoptosis,promoting neuronal regeneration,and inducing neural stem cell differentiation and migration,which plays an important role in the process of neural function recovery.This paper summarizes the structure and function of HMGB1,as well as its role in spinal cord injury,in order to provide direction for founding therapeutic target for neurological function recovery after spinal cord injury.
6.Association between maternal age and chromosomal status of pre-implantation embryos
Chunyan WEI ; Rong LI ; Changlong XU ; Ni′na LI ; Ying HUANG ; Jian ZHANG ; Qiuwen SHI
Chinese Journal of Medical Genetics 2025;42(3):257-263
Objective:To analyze the chromosome status of pre-implantation embryos from women of different ages, and assess the impact of age on it.Methods:A retrospective analysis was carried out on the results of PGT-A and PGT-M+ PGT-A cycles by whole-genome amplification followed by next generation sequencing at the Second People′s Hospital of Nanning between July 2021 and November 2023. The embryos were divided into five groups based on the women′s age: ≤ 30 years old group, 31 ~ 34 years old group, 35 ~ 37 years old group, 38 ~ 40 years old group, and ≥ 41 years old group. The chromosomal status of embryos for each group was compared. This study has been approved by the Ethic Committee of the Hospital (Ethics No. Y2024312A).Results:This study has involved 390 couples and 436 PGT cycles, with a total of 1 651 blastocysts biopsied and analyzed. Among these, 835 embryos (50.6%) were found to have chromosomal abnormalities, including 490 (29.7%) with aneuploidies, 154 (9.3%) with chromosomal segment abnormalities, and 264 (16.0%) with chromosome mosaicisms. After adjusting the dosages of Gn, female BMI, male age, PGT indications, infertility type, LH, AMH and other parameters, maternal age appeared to be an independent factor for chromosomal abnormalities and aneuploidies in blastocysts ( OR=1.132, 95% CI = 1.089 - 1.177, P<0.001; OR=1.250, 95% CI = 1.188-1.315, P<0.001). With the increase in female age, embryonic chromosome abnormalities have significantly increased in each group, with the rates being 32.3% (126/390), 43.1% (189/439), 45.1% (116/257), 66.3% (250/377), and 81.9% (154/188) ( P<0.001). Chromosomal aneuploidies have also significantly increased, with the rates being 8.2% (32/390), 16.6% (73/439), 24.5% (63/257), 49.6% (187/377), and 71.8% (135/188) ( P<0.001). The proportion of embryos with ≥ 2 chromosome abnormalities also significantly increased in abnormal embryos, with the rates being 28.6% (36/126), 30.2% (57/189), 39.7% (46/116), 48.4% (121/250), and 64.9% (100/154) ( P<0.001). Of note, the female age did not affect the prevalence of chromosomal segment abnormalities and mosaicisms (all P>0.05). Conclusion:The findings suggested that along with the increase infemale age, there was an increase in the rate of chromosomal abnormalities, at the same time, the type of chromosomal abnormality changed, mainly with an increased incidence of chromosomal aneuploidy, and the proportion of embryos involving multiple chromosomal abnormalities increases significantly.
7.TRIM25 inhibits Japanese encephalitis virus replication in U251 cells by up-regulation of the IFN-β and degrading the viral capsid protein
Chen CHEN ; Kui XU ; Zhuang ZHU ; Rong HUANG ; Yalan FENG ; Ning TAN ; Yajing HE ; Yue LUO ; Jian YANG ; Lei YUAN
Chinese Journal of Microbiology and Immunology 2025;45(2):99-107
Objective:To investigate the inhibitory effect of tripartite motif-containing 25 (TRIM25) on the replication of Japanese encephalitis virus (JEV) in cells and its molecular mechanism.Methods:Human glioma cells (U251 cells) and Kunming mice were infected with JEV, and then the cells and brain tissue samples were collected. The transcription levels of six TRIM genes were detected by real-time PCR, and the expression of TRIM25 in cells was detected by Western blot. U251 and A549 cells overexpressed with TRIM25 and U251 cells knocked out with TRIM25 gene were constructed. Cells were infected with JEV, and the replication of JEV was detected by viral plaque assay, real-time PCR and Western blot. The interaction of TRIM25 with viral proteins was investigated by co-immunoprecipitation (Co-IP) and indirect immunofluorescence assay. The expression of IFN-β in overexpressed TRIM25 cells was detected by real-time PCR and ELISA.Results:JEV infection promoted the expression of TRIM25 in cells and mouse brain tissues. TRIM25 overexpression restricted JEV replication in U251 and A549 cells, while TRIM25 knockout enhanced JEV replication. TRIM25 overexpression upregulated the level of IFN-β in cells. TRIM25 interacted with JEV capsid protein and promoted the degradation of capsid protein.Conclusion:TRIM25 can inhibit the replication of JEV in cells by upregulating IFN-β and promoting the degradation of JEV C protein.
8.Guidelines on the Technical Plan for Emergency Health Response to Acute Gelsemium Poisoning
Jiaxin JIANG ; Ruibo MENG ; Zhongxiang GAO ; Rongzong LI ; Weifeng RONG ; Weihui LIANG ; Shibiao SU ; Jian HUANG ; Cheng JIN ; LlU XIAOYONG
China Occupational Medicine 2025;52(2):203-206
Acute Gelsemium poisoning is a systemic disease primarily affecting the central nervous system and respiratory symptoms caused by the ingestion of a substantial amount of Gelsemium within a short period. It manifests as sudden onset and rapid progression, primarily caused by accidental ingestion due to misidentification, and posing significant health risks. The compilation of the Technical Plan for Emergency Health Response to Acute Gelsemium Poisoning describes in detail the specialized practice and technical requirements in the process of handling acute Gelsemium poisoning, including accident investigation and management, laboratory testing and identification, in-hospital treatment, and health monitoring. The guidelines clarify key procedures and requirements such as personal protection, investigation elements, etiology determination, medical rescue, and health education. The key to acute Gelsemium poisoning investigation lies in promptly identifying the toxin through exposure history, clinical manifestations, and sample testing. Because there is no specific antidote for Gelsemium poisoning, immediate removal from exposure, rapid elimination of the toxin, and respiratory monitoring are critical on-site rescue measures. Visual identification of food or herbal materials, followed by laboratory testing to determine Gelsemium alkaloids in samples is a rapid effective screening method. These guidelines offer a scientific, objective, and practical framework to support effective emergency responses to acute Gelsemium poisoning incidences.
9.Establishment and evaluation of a lipopolysaccharide-induced acute respiratory distress syndrome model in minipigs
Chuang-Ye WANG ; Ran WANG ; Jian ZHANG ; Ling-Xiao QIU ; Bin QING ; Heng YOU ; Jin-Cheng LIU ; Bin WANG ; Nan-Bo WANG ; Jia-Yu LI ; Xing LIU ; Shuang WANG ; Jin HU ; Jian WEN ; Quan LI ; Xiao-Ou HUANG ; Kun ZHAO ; Shuang-Lin LIU ; Gang LIU ; Mei-Ju WANG ; Qing XIANG ; Hong-Mei WU ; Xiao-Rong SUN ; Tao GU ; Dong ZHANG ; Qi LI ; Zhi XU
Medical Journal of Chinese People's Liberation Army 2025;50(9):1154-1161
Objective To establish a stable,reliable,and clinically relevant porcine model of endotoxin-induced acute respiratory distress syndrome(ARDS).Methods Ten 8-month-old male Bama minipigs were deeply sedated,followed by invasive mechanical ventilation and electrocardiographic monitoring.Lipopolysaccharide(LPS)was intravenously pumped at 600 μg/(kg·h)for 3 hours,then maintained at 15 μg/(kg·h)thereafter.Dynamic monitoring was performed at five time points after LPS injection(LPS 0,1,3,5,and 8 h),including arterial blood gas analysis and chest computed tomography(CT)scans.Pathological examination of lung tissues obtained via bronchoscopic biopsy(HE staining and transmission electron microscopy)was conducted.These indicators were comprehensively used to evaluate the success of the animal model.Results At 5 hours after LPS administration,8 minipigs developed symptoms such as skin cyanosis,elevated body temperature,and respiratory distress.The oxygenation index decreased to<300 mmHg.Chest CT scans showed diffuse pulmonary infiltrates.Histopathology revealed alveolar edema and hyaline membrane formation.Transmission electron microscopy demonstrated disruption of pulmonary blood-air barrier,depletion of lamellar bodies in type Ⅱ pneumocytes,inflammatory cell infiltration,and exudation of plasma proteins and fibrin.Compared with LPS 0 h,at LPS 8 h,the oxygenation index and arterial blood pH were significantly decreased(P<0.001),while blood lactic acid and serum potassium were significantly increased(P<0.05);serum calcium and base excess were significantly decreased(P<0.05),and the lung injury score based on HE-stained lung sections was significantly increased(P<0.01).Conclusion The porcine ARDS model established by continuous LPS injection can dynamically simulate the pathophysiological characteristics and typical pathological manifestations of clinical septic ARDS,making it an effective tool to study the pathogenesis,prevention,and treatment strategies of septic ARDS.
10.Association between maternal age and chromosomal status of pre-implantation embryos.
Chunyan WEI ; Rong LI ; Changlong XU ; Ni'na LI ; Ying HUANG ; Jian ZHANG ; Qiuwen SHI
Chinese Journal of Medical Genetics 2025;42(3):257-263
OBJECTIVE:
To analyze the chromosome status of pre-implantation embryos from women of different ages, and assess the impact of age on it.
METHODS:
A retrospective analysis was carried out on the results of PGT-A and PGT-M+PGT-A cycles by whole-genome amplification followed by next generation sequencing at the Second People's Hospital of Nanning between July 2021 and November 2023. The embryos were divided into five groups based on the women's age: ≤ 30 years old group, 31 ~ 34 years old group, 35 ~ 37 years old group, 38 ~ 40 years old group, and ≥ 41 years old group.The chromosomal status of embryos for each group was compared. This study has been approved by the Ethic Committee of the Hospital (Ethics No. Y2024312A).
RESULTS:
This study has involved 390 couples and 436 PGT cycles, with a total of 1 651 blastocysts biopsied and analyzed. Among these, 835 embryos (50.6%) were found to have chromosomal abnormalities, including 490 (29.7%) with aneuploidies, 154 (9.3%) with chromosomal segment abnormalities, and 264 (16.0%) with chromosome mosaicisms. After adjusting the dosages of Gn, female BMI, male age, PGT indications, infertility type, LH, AMH and other parameters, maternal age appeared to be an independent factor for chromosomal abnormalities and aneuploidies in blastocysts (OR = 1.132, 95%CI = 1.089-1.177, P < 0.001; OR = 1.250, 95%CI = 1.188-1.315, P < 0.001). With the increase in female age, embryonic chromosome abnormalities have significantly increased in each group, with the rates being 32.3% (126/390), 43.1% (189/439), 45.1% (116/257), 66.3% (250/377), and 81.9% (154/188) (P < 0.001). Chromosomal aneuploidies have also significantly increased, with the rates being 8.2% (32/390), 16.6% (73/439), 24.5% (63/257), 49.6% (187/377), and 71.8% (135/188) (P < 0.001). The proportion of embryos with ≥ 2 chromosome abnormalities also significantly increased in abnormal embryos, with the rates being 28.6% (36/126), 30.2% (57/189), 39.7% (46/116), 48.4% (121/250), and 64.9% (100/154) (P < 0.001). Of note, the female age did not affect the prevalence of chromosomal segment abnormalities and mosaicisms (all P > 0.05).
CONCLUSION
Above findings suggested that along with the increase in female age, there is an increase in the rate and complexity of chromosomal abnormalities, which may contribute to infertility in women with elder age.
Humans
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Female
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Maternal Age
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Adult
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Retrospective Studies
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Chromosome Aberrations
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Preimplantation Diagnosis/methods*
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Pregnancy
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Blastocyst/metabolism*
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Aneuploidy
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Fertilization in Vitro
;
Male

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