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1.
Rev Sci Instrum ; 95(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38578918

RESUMO

This paper presents a novel reaction microscope designed for ion-atom collision investigations, established at the Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China. Its time-of-flight (TOF) spectrometer employs an innovative flight-time focusing method consisting of two acceleration regions, providing optimal time focusing conditions for charged fragments with diverse initial velocities. The TOF spectrometer's axis intentionally tilts by 12° relative to the ion beam direction, preventing potential obstructions from the TOF grid electrodes. The introduced focusing method allows for a flexible time-focusing TOF spectrometer design without restricting the length ratio of the two regions. In addition, this configuration in our case significantly suppresses noise on the recoil ion detector produced by residual gas in the ion beam trajectory, which is a considerable challenge in longitudinal spectrometers. In a test experiment on the single electron capture reaction involving 62.5 keV/u He2+ ions and a helium atomic beam, the recoil longitudinal momentum resolution achieved 0.068 atomic units. This novel configuration and successful test run show excellent precision for ion-atom collision studies.

2.
Zhonghua Yi Xue Za Zhi ; 103(8): 578-584, 2023 Feb 28.
Artigo em Chinês | MEDLINE | ID: mdl-36822869

RESUMO

Objective: To investigate the knowledge, use and barriers when prescribing GLP-1RA and SGLT2i among cardiologists, endocrinologists and general practitioners, and explore the influencing factors that hinder the use of these medications. Methods: A questionnaire was conducted among physicians in the above departments in Peking University Third Hospital and health service institutions at all levels in its medical consortium. A total of 342 physicians were involved. Among them, 40.6% (139) were cardiologists, 28.9% (99) were endocrinologists and 30.4% (104) were general practitioners; 66.7% (270) came from Beijing while 33.3% (72) from other provinces. The survey included clinicians' knowledge and current use of GLP-1RA and SGLT2i, and the possible reasons that influenced the prescription of these medications. Medical therapies of physicians were investigated by simulating different clinical scenarios. The difference of measures among physicians in different departments was compared. Results: A total of 342 physicians were involved, with the average age of 40 (35, 46) years old and the average working time of 13 (7, 20) years. Among them, 40.6% (139) were male. 77.5% (265) physicians had comprehensive knowledge of SGLT2i and prescribed it, which was higher than that for GLP-1RA (70.5%, 241) (P<0.001). 21.1% (72) physicians prescribed SGLT2i more than 20 times per month, which was higher than that for GLP-1RA (8.2%, 28) (P<0.001). Endocrinologists had more knowledge and prescribed more GLP-1RA and SGLT2i compared with other physicians (both P values<0.001). 38.1% (53) cardiologists, 22.2% (22) endocrinologists, and 30.8% (32) general practitioners believed patients needed an endocrinologist to evaluate and adjust GLP-1RA, which was the primary barrier for the use of medications (P=0.042). 27.4% (38) cardiologists, 14.1% (14) endocrinologists, and 30.8% (32) general practitioners believed patients needed an endocrinologist to evaluate and adjust SGLT2i, which was the primary barrier for the use of medications (P=0.018). 21.6% (30) cardiologists, 45.5% (45) endocrinologists, and 31.7% (33) general practitioners believed side effects of SGLT2i was the primary barrier for the use of medications (P<0.001). For patients with unqualified glycemic control and cardiovascular complications, 65.4% (75) cardiologists, 69.7% (69) endocrinologists, and 43.3% (45) general practitioners chose the above medications (P<0.001). For patients with qualified glycemic control, combined with cardiovascular complications and diabetic organ damage, 35.3% (49) cardiologists, 52.5% (52) endocrinologists, and 25.0% (26) general practitioners chose the above medications (P<0.001). Conclusions: Physicians had more knowledge and prescription of SGLT2i than that of GLP-1RA. Endocrinologists had more knowledge and prescription of the above medications than other physicians. The side effect of medications was potential primary barrier for the use of the novel hypoglycemic agent with cardiovascular benefits. In clinical practice, most of physicians considered that high-risk patients with cardiovascular comorbidities need to be referred to cardiologist or endocrinologist to adjust clinical therapies.


Assuntos
Sistema Cardiovascular , Diabetes Mellitus Tipo 2 , Cardiopatias , Médicos , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Feminino , Hipoglicemiantes/uso terapêutico , Diabetes Mellitus Tipo 2/complicações , Mediastino , Cardiopatias/complicações
3.
Phys Rev Lett ; 131(25): 253001, 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38181359

RESUMO

Interatomic Coulombic decay (ICD) is a significant fragmentation mechanism observed in weakly bound systems. It has been widely accepted that ICD-induced molecular fragmentation occurs through a two-step process, involving ICD as the first step and dissociative-electron attachment (DEA) as the second step. In this study, we conducted a fragmentation experiment of ArCH_{4} by electron impact, utilizing the coincident detection of one electron and two ions. In addition to the well-known decay pathway that induces pure ionization of CH_{4}, we observed a new channel where ICD triggers the ionization dissociation of CH_{4}, resulting in the cleavage of the C-H bond and the formation of the CH_{3}^{+} and H ion pair. The high efficiency of this channel, as indicated by the relative yield of the Ar^{+}/CH_{3}^{+} ion pair, agrees with the theoretical prediction [L. S. Cederbaum, J. Phys. Chem. Lett. 11, 8964 (2020).JPCLCD1948-718510.1021/acs.jpclett.0c02259; Y. C. Chiang et al., Phys. Rev. A 100, 052701 (2019).PLRAAN2469-992610.1103/PhysRevA.100.052701]. These results suggest that ICD can directly break covalent bonds with high efficiency, bypassing the need for DEA. This finding introduces a novel approach to enhance the fragmentation efficiency of molecules containing covalent bonds, such as DNA backbone.

4.
Zhonghua Yi Xue Za Zhi ; 102(46): 3698-3703, 2022 Dec 13.
Artigo em Chinês | MEDLINE | ID: mdl-36509542

RESUMO

Objective: To explore the effect of "one-stop" outpatient management on the therapeutic schedule and control rate of patients with metabolic disorders. Methods: A total of 332 patients who met the inclusion criteria were enrolled and treated regularly in the "one-stop" outpatient department of the Department of Cardiology of the Third Hospital of Peking University from November 1, 2020 to April 30, 2022. The general information, personal history, family history, drug treatment plan, blood pressure, height, weight, waist circumference, and hip circumference of patients were collected through the outpatient electronic medical record system, and patients were followed up through conducting "one-stop" comprehensive management. The baseline clinical characteristics were analyzed, and the changes of metabolic indexes, treatment conditions and control rate of patients with different metabolic disorders before and after the "one-stop" outpatient management were compared. Results: The time interval between the first visit and the last visit was 44 (26, 60) weeks in 332 patients, whose age was (57.2±13.2) years, including 219 males (66.0%). After the "one-stop" outpatient management, fasting blood glucose (FBG) [ 6.6 (5.6, 7.9) mmol/L vs 6.3 (5.6, 6.9) mmol/L], glycosylated hemoglobin A1c (HbA1c) [ (7.2±1.5) % vs (6.6±0.8) %], low density lipoprotein cholesterol (LDL-C) [ 2.70 (1.97, 3.55) mmol/L vs 2.04 (1.66, 2.63) mmol/L] and blood uric acid (UA) [ (383.7±107.1) µmol/L vs (341.2±90.6) µmol/L] all decreased significantly (all P values<0.05). The control rates of hypertension (19.8% vs 28.2%), diabetes (45.2% vs 66.5%), hyperlipidemia (54.9% vs 87.6%) and hyperuricemia (16.7% vs 49.0%) were significantly improved after the "one-stop" outpatient management (all P values<0.05). Conclusion: The "one-stop" outpatient management of cardiovascular department can significantly improve the metabolic condition and the control rate of patients with multiple metabolic disorders.


Assuntos
Diabetes Mellitus , Hipertensão , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Hemoglobinas Glicadas , Circunferência da Cintura , Pressão Sanguínea , Glicemia
5.
J Chem Phys ; 157(15): 154309, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36272776

RESUMO

The fragmentation dynamics of two isomers of C3H6, cyclopropane and propene, induced by 4 keV/u Ar8+ are investigated employing a reaction microscope. Four two-body and two three-body dissociation channels of C3H6 2+ dications are identified for each isomer, among which the channels involving CC bond breaking are found to be much more favored than H3 + and H2 + formation channels. The observation of the CH3 + or H3 + formation channels from cyclopropane are direct evidence of the proton migration within the carbon skeleton before dissociation. Obvious isomer effects are revealed by comparing the relative branching ratios of different channels of the two isomers. Moreover, it was shown that a sequential dissociation mechanism with H elimination prior to CC bond cleavage may be dominant for the two three-body dissociation channels for both isomers.

6.
Beijing Da Xue Xue Bao Yi Xue Ban ; 52(3): 420-424, 2020 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-32541972

RESUMO

OBJECTIVE: The pathogenesis of myocardial injury upon corona virus disease 2019 (COVID-19) infection remain unknown,evidence of impact on outcome is insufficient, therefore, we aim to investigate the risk factors for death among COVID-19 patients combined with hypertension, coronary heart disease or diabetes in this study. METHODS: This was a single-centered, retrospective, observational study. Patients of Sino-French Eco-City section of Tongji Hospital, Wuhan, China attended by Peking University Supporting Medical Team and admitted from Jan. 29, 2020 to Mar. 20, 2020 were included. The positive nucleic acid of COVID-19 virus and combination with hypertension, coronary heart disease or diabetes were in the standard. We collected the clinical data and laboratory examination results of the eligible patients to evaluate the related factors of death. RESULTS: In the study, 94 COVID-19 patients enrolled were divided into the group of death (13 cases) and the group of survivors (81 cases), the average age was 66.7 years. Compared with the survival group, the death group had faster basal heart rate(103.2 beats/min vs. 88.4 beats /min, P=0.004), shortness of breath(29.0 beats /min vs. 20.0 beats /min, P<0.001), higher neutrophil count(9.2×109/L vs. 3.8×109/L, P<0.001), lower lymphocyte count(0.5×109/L vs. 1.1×109/L, P<0.001), creatine kinase MB(CK-MB, 3.2 µg/L vs. 0.8 µg/L, P<0.001), high sensitivity cardiac troponin Ⅰ(hs-cTnⅠ, 217.2 ng/L vs. 4.9 ng/L, P<0.001), N-terminal pro brain natriuretic peptide(NT-proBNP; 945.0 µg/L vs. 154.0 µg/L, P<0.001), inflammatory factor ferritin(770.2 µg/L vs. 622.8 µg/L , P=0.050), interleukin-2 recepter(IL-2R, 1 586.0 U/mL vs. 694.0 U/mL, P<0.001), interleukin-6(IL-6, 82.3 ng/L vs. 13.0 ng/L, P<0.001), interleukin-10(IL-10, 9.8 ng/L vs. 5.0 ng/L, P<0.001)were higher than those in the survival group. Univariate logistic regression analysis showed that the risk factors for death were old age, low non oxygen saturation, low lymphocyte count, myocardial injury, abnormal increase of IL 2R, IL-6, and IL-10. Multivariate regression showed that old age (OR=1.11, 95%CI=1.03-1.19, P=0.026), low non oxygen saturation(OR=0.85, 95%CI=0.72-0.99, P=0.041), and abnormal increase of IL-10(>9.1 ng/L, OR=101.93, 95%CI=4.74-2190.71, P=0.003)were independent risk factors for COVID-19 patients combined with hypertension, coronary heart disease or diabetes. CONCLUSION: In COVID-19 patients combined with hypertension, coronary heart disease or diabetes, the risk factors for death were old age, low non oxygen saturation, low lymphocyte count, myocardial injury, and abnormal increase of IL-2R, IL-6, and IL-10. Old age, low non oxygen saturation and abnormal increase of IL-10 were independent risk factors.


Assuntos
Doença das Coronárias , Infecções por Coronavirus , Diabetes Mellitus , Hipertensão , Pandemias , Pneumonia Viral , Idoso , Betacoronavirus , COVID-19 , China/epidemiologia , Doença das Coronárias/complicações , Infecções por Coronavirus/complicações , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/mortalidade , Humanos , Hipertensão/complicações , Pneumonia Viral/complicações , Pneumonia Viral/epidemiologia , Pneumonia Viral/mortalidade , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2
7.
Beijing Da Xue Xue Bao Yi Xue Ban ; 53(1): 159-166, 2020 Dec 28.
Artigo em Chinês | MEDLINE | ID: mdl-33550351

RESUMO

OBJECTIVE: To investigate the risk factors for acute myocardial injury in coronavirus disease 2019 (COVID-19) patients. METHODS: This is a retrospective analysis of a COVID-19 cohort, in which 149 confirmed COVID-19 patients enrolled were divided into the group of myocardial injury (19 cases) and the group of non-myocardial injury (130 cases). Myocardial injury was defined according to Fourth universal definition of myocardial infarction released by European Society of Cardiology (ESC) in 2018, that cardiac troponin (cTn) was above 99th percentile of the reference level. Clinical information and results of laboratory tests of the eligible patients were collected. Factors associated with myocardial injury in COVID-19 patients were evaluated. RESULTS: Compared with the group of non-injury, the patients in the group of injury were older and had a larger proportion of severe or critical cases (P < 0.05), higher respiratory rate and lower percutaneous oxygen saturation (SpO2) without oxygen therapy on admission (P < 0.05). All inflammatory indexes except for tumor necrosis factor α (TNF-α) showed significant elevation in the patients of the group of injury (P < 0.05). Analyzed by Spearman correlation test, we showed that the levels of circulatory cTnI were in positive correlation with the levels of high-sensitivity C-reactive protein (hs-CRP), ferritin, receptor of interleukin-2 (IL-2R), interleukin-6 (IL-6) and interleukin-8 (IL-8) (ρ > 0, P < 0.05). Lower SpO2 without oxygen therapy on admission (OR: 0.860, 95%CI: 0.779-0.949, P=0.003) and higher plasma IL-6 levels (OR: 1.068, 95%CI: 1.019-1.120, P=0.006) were independent risk factors for acute myocardial injury in the patients with COVID-19 by multivariate Logistic regression analyses. CONCLUSION: Hypoxic state and inflammation may play a key role in the pathogenesis of acute myocardial injury in COVID-19 patients.


Assuntos
COVID-19 , Biomarcadores , Humanos , Hipóxia , Inflamação , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2
8.
Zhonghua Yi Xue Za Zhi ; 98(27): 2152-2156, 2018 Jul 17.
Artigo em Chinês | MEDLINE | ID: mdl-30032516

RESUMO

Objective: To evaluate the effect of patient education and tailored exercise in the knee osteoarthritis (OA) patients. Methods: One hundred and eighty-five patients with knee OA were enrolled in this ongoing prospective cohort study at Arthritis Clinic and Research Center, Peking University People's Hospital since May, 2016.The treatment consisted of two one-hour sessions of patient education and six weeks of supervised, in-group, tailored exercise.The contents of the patient education were evidence-based and its overall focus was to increase the knowledge of the participants regarding OA and how to treat it.The exercise program was a neuromuscular exercise based on biomechanical and neuromuscular principles that aimed at restoring a neutral functional alignment of the lower extremities by improving sensorimotor control and obtaining compensatory functional stability.The outcomes were evaluated at baseline, 3 and 6 months, which included pain on the visual analogue scale (VAS, 0-100), quality of life on the Euro-quality of life-5 Dimensional (EQ-5D) VAS form, Knee Injury and Osteoarthritis Outcome Score (KOOS), 30-second chair stand test, 40-meter walk test and use of analgesics.The participants were also asked to rate their opinion of this program on a five-point scale (very satisfactory, satisfactory, neither satisfactory nor dissatisfactory, dissatisfactory, very dissatisfactory). One way analysis of variance was applied to compare the outcomes at baseline and 3 and 6 months follow-up. Results: One hundred and forty-two participants completed the 6-month follow-up.There were significant improvements in pain VAS, EQ-5D-VAS, 30-second chair stand test and 40-meter walk test at the follow-up at 3 and 6 months when compared with those at baseline (F=22.9, 8.4, 3.4, 4.1, 3.8, all P<0.05). The rate of analgesics use in the past two week at baseline was 43.2%, and it decreased to 18.9% at 6-month follow-up (P<0.001). Most participants (71.1%, 101 out of 142) rated the program as 'Very Satisfactory' and the rest (28.9%, 41 out of 142) rated the program as 'Satisfactory'. Conclusion: This program comprising the group patient education and tailored exercise therapy is effective in relieving pain, improving the function and quality of life in patients with knee OA.


Assuntos
Terapia por Exercício , Osteoartrite do Joelho , Exercício Físico , Humanos , Joelho , Medição da Dor , Estudos Prospectivos , Qualidade de Vida
9.
Genet Mol Res ; 14(4): 17134-44, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26681060

RESUMO

The aim of this study was to investigate the correlation between MACC1 expression and resistance to cisplatin (DDP) in DDP-resistant human epithelial ovarian cancer SKOV-3 cells (SKOV-3/DDP). MACC1 mRNA and protein expression levels in SKOV-3 and SKOV-3/DDP cells were detected by reverse transcriptase polymerase chain reaction and western blot. The SKOV-3/DDP cells were divided into 5 groups: control, shVect (transfected with p-super-EGFP-1 plasmid), pshMACC1 (transfected with psuper-EGFP-shMACC1 plasmid), PD (pretreated with 20 µM PD98059), and combined (transfected with psuper-EGFP-shMACC1 plasmid and pretreated with 20 µM PD98059) groups. Cisplatin sensitivity and cell apoptosis in SKOV-3/DDP cells were assayed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and flow cytometry. ERK1/2 and p-ERK1/2 expression was determined by western blot. MACC1 mRNA and protein expression levels in SKOV-3/DDP cells were 2.66 ± 0.54 and 1.95 ± 0.45 times those seen in SKOV-3 cells (P < 0.05). Cisplatin sensitivity of pshMACC1 group was much higher than that in the control and shVect groups. Cisplatin-induced cell apoptosis rates increased significantly in the pshMACC1, PD, and combined groups, compared to the control and shVect groups. Moreover, the apoptosis rate was the highest in the combined group among the 5 groups (IC50 = 20.836 ± 0.629 µM). p-ERK1/2 expression decreased significantly in the pshMACC1, PD, and combined groups (this decrease was the most obvious in the combined group). In conclusion, downregulation of MACC1 expression could enhance cisplatin sensitivity and decrease drug resistance in SKOV- 3/DDP cells.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição/genética , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo , Técnicas de Silenciamento de Genes , Humanos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , Transativadores , Fatores de Transcrição/metabolismo
10.
Shanghai Kou Qiang Yi Xue ; 1(2): 91-4, 1992 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-15159899

RESUMO

This research was made in a mandibular that simulated dynamic relationship between occlusion,masticatory muscles and TMJ and that has full and normal teeth excepting the right second premolar was lost.This study measue\red and analysed the stress distribution and changing in the abutments and the supporting alveolar bone with strain gauge when the edentulous are was restored by T-type attachment and rest type connectors semifixed bridge.The results suggested that:(1)The stress of the abutment and alveolar bone increased by prematurity and it's distribution and changing were different according to the place of prematurity and type of the connectors.(2) T-type connecter has stress broken action and rest connector hasn't obvious such an action when prematurity of central occlusion.

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