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1.
Opt Express ; 32(9): 16398-16413, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38859267

ABSTRACT

Attosecond electron bunches have wide application prospects in free-electron laser injection, attosecond X/γ-ray generation, ultrafast physics, etc. Nowadays, there is one notable challenge in the generation of high-quality attosecond electron bunch, i.e., how to enhance the electron bunch density. Using theoretical analysis and three-dimensional particle-in-cell simulations, we discovered that a relativistic vortex laser pulse interacting with near-critical density plasma can not only effectively concentrate the attosecond electron bunches to over critical density, but also control the duration and density of the electron bunches by tuning the intensity and carrier-envelope phase of the drive laser. It is demonstrated that this method can efficiently produce attosecond electron bunches with a density up to 300 times of the original plasma density, peak divergence angle of less than 0.5 ∘, and duration of less than 67 attoseconds. Furthermore, by using near-critical density plasma instead of solid targets, our scheme is potential for the generation of high-repetition-frequency attosecond electron bunches, thus reducing the requirements for experiments, such as the beam alignment or target supporter.

2.
Zhonghua Yi Xue Za Zhi ; 104(15): 1310-1315, 2024 Apr 16.
Article in Zh | MEDLINE | ID: mdl-38637167

ABSTRACT

Objective: To investigate the imaging factors associated with postoperative cerebral infarction in adult patients aged 18 and above with ischemic Moyamoya disease. Methods: The clinical data of adult patients who underwent surgeries for ischemic Moyamoya disease in the Department of Neurosurgery at Peking University International Hospital from October 2015 to October 2020 were retrospectively analyzed. Of the 239 patients, 120 were male and 119 were female, with ages ranging from 18 to 63 (41.7±10.3) years. A total of 239 patients(290 cases) underwent direct and indirect combined revascularization (CR).Gender, age, surgical side, preoperative transient ischemic attack (TIA), presence of old cerebral infarction, and imaging features were compared between the patients with (48 cases) and without (242 cases) cerebral infarction within 1 week after surgery. Multivariate logistic binary regression model was used to analyze the imaging risk factors of postoperative cerebral infarction. Results: Cerebral infarction occurred in 48 cases(16.5%) among the 290 CR group within 1 week after surgery. The proportion of patients with TIA, old cerebral infarction, ICA stenosis, A1 segment stenosis, M1 segment stenosis, abnormal posterior cerebral artery (PCA), and unstable compensation before CR in the cerebral infarction group was higher than that in the non-cerebral infarction group (P<0.05).Preoperative TIA (OR=4.514, 95%CI: 1.920-10.611), old cerebral infarction (OR=2.856,95%CI:1.176-6.936), A1 stenosis (OR=7.027,95%CI:1.877-26.308), M1 stenosis (OR=6.968,95%CI:2.162-22.459), abnormal PCA (OR=4.114,95%CI:1.330-12.728)and unstable compensation (OR=4.488,95%CI:1.194-16.865) were risk factors for cerebral infarction after CR surgery (all P<0.05). Conclusion: Among the imaging factors, TIA, old cerebral infarction, A1 stenosis, M1 stenosis, abnormal PCA and unstable compensation were risk factors for cerebral infarction in adult patients with ischemic Moyamoya disease treated by combined revascularization.


Subject(s)
Cerebral Revascularization , Ischemic Attack, Transient , Moyamoya Disease , Adult , Humans , Male , Female , Moyamoya Disease/surgery , Retrospective Studies , Constriction, Pathologic/complications , Cerebral Revascularization/adverse effects , Cerebral Revascularization/methods , Cerebral Infarction , Risk Factors , Treatment Outcome
3.
Zhonghua Yi Xue Za Zhi ; 104(32): 3050-3058, 2024 Aug 20.
Article in Zh | MEDLINE | ID: mdl-39143773

ABSTRACT

Objective: To construct a repetitive implantation failure (RIF)-related competitive endogenous RNA (ceRNA) regulatory network and validate with clinical samples. Methods: RIF-related long non-coding RNA (lncRNA), microRNA (miRNA) and messenger RNA (mRNA) from the high-throughput gene expression omnibus (GEO) database Expression profile data set were obtained to construct a ceRNA regulatory network of lncRNA-miRNA-mRNA. At the same time, weighted gene co-expression network analysis (WGCNA) was used to explore hub genes in the network. This retrospective study collected RIF patients and controls (at least one pregnancy history after assisted conception) who underwent in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) for assisted pregnancy from 2020 to 2021 at the Reproductive Medicine Center of the First Affiliated Hospital of Zhengzhou University. In the endometrial tissue of patients with 1 pregnancy history, real-time fluorescence quantitative polymerase chain reaction (qRT-PCR) was used to verify the mRNA expression levels of RIF-related hub genes, and Western blotting and immunohistochemistry were used to verify protein expression levels of vascular cell adhesion molecule-1 (VCAM1). Results: A RIF-related ceRNA regulatory network consisting of 32 lncRNAs, 31 miRNAs and 88 mRNAs was constructed, and 7 RIF-related hub genes were identified using WGCNA. By intersecting 88 mRNAs and hub genes in the ceRNA network, two RIF-related key genes were obtained, i.e., VCAM1 and interleukin-2 receptor α (interleukin-2 receptor α, IL-2RA). In clinical verification, the ages of the control group and RIF group [M (Q1, Q3)] were 26.50 (25.00, 34.00) and 30.50 (25.75, 35.25) years old, respectively (P>0.05). Compared with the control group, the mRNA [0.30 (0.15, 0.42) vs 0.99 (0.69, 1.34), P=0.001] and protein expression [0.44 (0.16, 1.27) vs 2.39 (1.58, 2.58), P<0.001] of VCAM1 in the endometrium of the RIF group were both reduced. Conclusions: This study uses bioinformatics analysis methods to construct a RIF-related ceRNA regulatory network, and it is confirmed through clinical samples that the expression level of VCAM1 in the endometrial tissue of RIF patients is significantly reduced.


Subject(s)
Embryo Implantation , Fertilization in Vitro , Gene Regulatory Networks , RNA, Competitive Endogenous , Female , Humans , Pregnancy , Embryo Implantation/genetics , Endometrium/metabolism , Gene Expression Profiling , MicroRNAs/genetics , Retrospective Studies , RNA, Competitive Endogenous/genetics , RNA, Long Noncoding/genetics , RNA, Messenger/genetics , Sperm Injections, Intracytoplasmic , Vascular Cell Adhesion Molecule-1/genetics , Vascular Cell Adhesion Molecule-1/metabolism
4.
Zhonghua Yi Xue Za Zhi ; 104(9): 704-707, 2024 Mar 05.
Article in Zh | MEDLINE | ID: mdl-38418170

ABSTRACT

A total of 82 patients with temporal lobe epilepsy (TLE) and temporal plus epilepsy (TPE)admitted in Xuanwu Hospital from January 1, 2019, to January 1, 2021 were restrospectively analyzed, including 41 males and 41 females, aged 2 to 52 (24±10) years. The patients were randomly divided into the training set (58 cases) and test set (24 cases) by Python. FreeSurfer software was used to segment the cortex of the affected hemisphere, defining 33 regions of interest (ROIs), and radiomics features were extracted by Python. After selecting features using the filter-based feature selection method, a radiomics model was constructed with a logistic regression classifier, and radiomics scores were calculated. Combining clinical characteristics with radiomics scores, a nomogram model was constructed using R software, the predictive accuracy of the model was assessed with the concordance index (C-index), and the model's goodness-of-fit was tested with the Hosmer-Lemeshow method. The results showed statistically significant differences between TLE and TPE patients in disease duration, intracranial electrode implantation, and hippocampal sclerosis (both P<0.05). The accuracy of the radiomics model in the training set and the test set was 91.4% and 87.5%, respectively. The nomogram model uses C-index to predict accuracy. Hosmer-Lemeshow method was used to test the goodness of fit, with AUCs of 0.95 (95%CI: 0.853-0.991) in the training set and 0.84 (95%CI: 0.676-0.999) in the test set. The study indicates that the radiomics nomogram model based on MPRAGE sequences can effectively differentiate TLE from TPE, providing reference for the development of personalized treatment plans in clinical practice.


Subject(s)
Epilepsy, Temporal Lobe , Epilepsy , Female , Male , Humans , Epilepsy, Temporal Lobe/diagnostic imaging , Nomograms , Radiomics , Area Under Curve , Retrospective Studies
7.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 35(6): 565-572, 2024 Jan 25.
Article in Zh | MEDLINE | ID: mdl-38413017

ABSTRACT

OBJECTIVE: To investigate the distribution of malaria vector Anopheles in Sichuan Province from 2011 to 2021, so as to provide the scientific evidence for improving the surveillance of malaria vector Anopheles and preventing re-establishment of imported malaria in Sichuan Province. METHODS: The density and species of Anopheles mosquitoes were investigated using human-bait trapping and light trapping techniques in malaria vector surveillance sites of Sichuan Province from 2011 to 2021. The number, population and density of captured Anopheles mosquitoes were collected and descriptively analyzed, and the geographical distribution map of malaria vectors was plotted using the software ArcGIS 10.7 in Sichuan Province. RESULTS: A total of 152 243 Anopheles mosquitoes were captured in malaria vector surveillance sites of Sichuan Province from 2011 to 2021, including 150 987 An. sinensis (99.18%) and 1 256 An. anthropophagus (0.82%), and no other Anopheles species were captured. The annual densities of An. sinensis and An. anthropophagus were 0.64 to 1.27 mosquitoes/(person-hour) and 0 to 0.07 mosquitoes/(person-hour) by the human-bait trapping technique, and 6.46 to 26.50 mosquitoes/(light-night) and 0 to 0.82 mosquitoes/(light-night) by the light trapping technique in malaria vector surveillance sites of Sichuan Province from 2011 to 2021. A relatively higher density of An. anthropophagus was seen in Renshou County, Jianyang City, Weiyuan County and Mabian Yi Autonomous County [> 0.40 mosquitoes/(person-hour)] by the human-bait trapping technique, and in Cuiping District and Gaoxian County in Yibin City [> 1.00 mosquito/(light-night)] by the light trapping technique in Sichuan Province from 2011 to 2018, with no An. anthropophagus captured from 2019 to 2021, and a relatively higher density of An. sinensis was detected in Emeishan City, Lushan County, Luojiang District, Tongchuan District and Zhaohua District [> 4.00 mosquitoes/(person-hour)] by the human-bait trapping technique, and in Huili County, Yuexi County, Dechang County, Langzhong City, Pingchang County and Xuanhan County [> 40.00 mosquitoes/(light-night)] by the light trapping technique in Sichuan Province from 2011 to 2021. CONCLUSIONS: Malaria vectors were still widespread in Sichuan Province from 2011 to 2021, and An. sinensis was the dominant species of malaria vectors. There is still a risk of local re-establishment of imported malaria in Sichuan Province, and it is needed to continue to improve the surveillance of imported malaria cases and malaria vectors.


Subject(s)
Anopheles , Malaria , Animals , Humans , Malaria/epidemiology , Malaria/prevention & control , Mosquito Vectors , Population Density , China/epidemiology
8.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 36(2): 169-173, 2024 May 09.
Article in Zh | MEDLINE | ID: mdl-38857961

ABSTRACT

OBJECTIVE: To investigate the prevalence of Echinococcus infections in small rodents around human residential areas in Yushu City, Qinghai Province in 2023, so as to provide insights into precision echinococcosis control. METHODS: One or two quadrats, each measuring 50 m × 50 m, were randomly assigned in Shanglaxiu Township and Longbao Township, Yushu City, Qinghai Province on June 2023, respectively, and 300 plate-type mouse traps, each measuring 12.0 cm × 6.5 cm, were assigned in each quadrat. Small rodents were captured during the period between 10 : 00 and 18 : 00 each day for 4 days. Then, all captured small rodents were identified and dissected, and liver specimens with suspected Echinococcus infections were subjected to pathological examinations. The Echinococcus cytochrome c oxidase 1 (cox1) gene was amplified using PCR assay, and the sequence of the amplified product was aligned to that was recorded in the GenBank to characterize the parasite species. In addition, a phylogenetic tree of Echinococcus was generated based on the cox1 gene sequence using the neighbor-joining method. RESULTS: A total of 236 small rodents were captured in Shanglaxiu and Longbao townships, Yushu City, including 65 Qinghai voles and 51 plateau pikas in Shanglaxiu Township, and 62 Qinghai voles and 58 plateau pikas in Longbao Township, and there was no significant difference in the constituent ratio of small rodents between the two townships (χ2 = 0.294, P > 0.05). Seven plateau pikas and 12 Qinghai voles were suspected to be infected with Echinococcus by dissection, and pathological examinations showed unclear structure of hepatic lobules and disordered hepatocyte arrangement in livers of small rodents suspected of Echinococcus infections. PCR assay identified E. shiquicus DNA in 7 Qinghai voles, which were all captured from Shanglaxiu Township. Phylogenetic analysis showed that the cox1 gene sequence of Echinococcus in small rodents was highly homologous to the E. shiquicus cox1 gene sequence reported previously. CONCLUSIONS: Plateau pika and Qinghai vole were predominant small rodents around human residential areas in Yushu City, Qinghai Province in 2023, and E. shiquicus infection was detected in Qinghai voles.


Subject(s)
Echinococcosis , Echinococcus , Phylogeny , Rodentia , Animals , Echinococcosis/epidemiology , Echinococcosis/veterinary , Echinococcosis/parasitology , China/epidemiology , Echinococcus/genetics , Echinococcus/isolation & purification , Echinococcus/classification , Rodentia/parasitology , Prevalence , Humans
9.
J Nutr Health Aging ; 27(12): 1255-1261, 2023.
Article in English | MEDLINE | ID: mdl-38151877

ABSTRACT

This prospective study assessed the effectiveness of screening older long-term care residents (LTCRs) for fracture risk and osteoporosis in Taiwan. Fracture risk screening was done using the Fracture Risk Assessment Tool (FRAX), and those with high or moderate risk were offered osteoporosis workup and treatment at the hospital. Among 785 LTCRs screened, 338 men (mean age 75.6) and 447 women (mean age 81.2) were included. Only 5.2% of women and no men were using anti-osteoporosis medication. Based on the Bone Health and Osteoporosis Foundation (BHOF) recommendations, 69.2% of men and 92.6% of women were classified as high fracture risk. In 110 participants willing to receive bone mineral density examination, osteoporosis was diagnosed in 86.2% of women and half of men. FRAX could effectively differentiate fracture risk in 648 LTCRs who completed 2-year follow-ups; no fracture occurred in the low-risk group. The study emphasizes the importance of fracture risk screening to enhance osteoporosis diagnosis and treatment among LTCRs.


Subject(s)
Fractures, Bone , Osteoporosis , Osteoporotic Fractures , Male , Female , Humans , Aged , Aged, 80 and over , Prospective Studies , Long-Term Care , Risk Assessment , Osteoporosis/complications , Osteoporosis/diagnosis , Osteoporosis/drug therapy , Fractures, Bone/epidemiology , Fractures, Bone/etiology , Fractures, Bone/prevention & control , Bone Density , Risk Factors , Osteoporotic Fractures/epidemiology , Osteoporotic Fractures/etiology , Osteoporotic Fractures/prevention & control , Absorptiometry, Photon
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