RÉSUMÉ
Computational fluid dynamics (CFD) is an emerging technology applied in the field of cardiovascular medicine, which can obtain hemodynamic data by simulating the blood flow in the patient's heart for cardiac function assessment and disease diagnosis. Left ventricular function plays a key role in the occurrence and development of cardiomyopathies and coronary disease. CFD can reconstruct the left ventricular anatomic structures of patients to clarify pathophysiologic mechanisms and analyze hemodynamic parameters to evaluate left ventricular function, verify surgical efficacy, and guide surgical strategy, which has a positive effect on achieving early diagnosis and reducing mortality from cardiomyopathies and coronary disease. At present, there are still technical limitations in the large-scale clinical application of CFD, and various solutions are being developed and tested, and further improvement and refinement are needed.
Sujet(s)
Cardiomyopathies , Hydrodynamique , Fonction ventriculaire gauche , Humains , Cardiomyopathies/physiopathologie , Fonction ventriculaire gauche/physiologie , Maladie coronarienne/physiopathologie , Simulation numérique , Hémodynamique , Modèles cardiovasculairesRÉSUMÉ
Objective: To study the clinical features and related factors of invasive pulmonary aspergillosis (IPA) in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Methods: This retrospective study enrolled patients hospitalized for AECOPD in ten tertiary hospitals of China from September 2017 to July 2021. AECOPD patients with IPA were included as case group, AECOPD patients without IPA were randomly selected as control group from the same hospitals and same hospitalization period as the patients with IPA using the random function in the software of Microsoft Excel 2003, at a ratio of 2â¶1. The clinical characteristics, treatment and outcome were compared between the two groups. Binary logistic regression model was used to analyze the factors associated with IPA in AECOPD patients. Results: A total of 14 007 inpatients with AECOPD were included in this study, and 300 patients were confirmed to have IPA, with an incidence rate of 2.14%. According to the above matching method, 600 AECOPD patients without aspergillus infection were enrolled as the control group. The age of the case group and the control group were (72.5±9.7) and (73.5±10.3) years old, with 78.0%(n=234) male and 76.8%(n=461) male, respectively. There were no significant differences in age and gender composition between the two groups (all P>0.05). The prognosis of case group was significantly worse than that of the control group, with longer hospital stay [M(Q1,Q3)], [14 (10-20) d vs 11 (8-15) d, P<0.001], higher ICU admission rate [16.3% (49 case) vs 10.0% (60 case), P=0.006], higher in-hospital mortality [4.0% (12 cases) vs 1.3% (8 cases), P=0.011], and higher hospitalization costs (28 000 ¥ vs 13 700 ¥, P<0.001). The smoking index of the case group and proportions of patients with diabetes mellitus, chronic pulmonary heart disease in the case group were significantly higher than those in control group (all P<0.05). In terms of clinical features, the proportions of patients with cough, expectoration, purulent sputum, hemoptysis and fever in the case group were higher than those in the control group, the serum albumin was significantly lower than that in the control group, and the proportions of patients with bronchiectasis and pulmonary bullae on imaging were significantly higher than those in the control group (all P<0.05). Diabetes (OR=1.559, 95%CI: 1.084-2.243), chronic pulmonary heart disease (OR=1.476, 95%CI: 1.075-2.028), bronchiectasis (OR=1.506, 95%CI: 1.092-2.078), pulmonary bullae (OR=1.988, 95%CI: 1.475-2.678) and serum albumin<35 g/L (OR=1.786, 95%CI: 1.325-2.406) were the related factors of IPA in patients with AECOPD. Conclusions: The incidence of IPA in AECOPD patients is relatively high and the prognosis of these patients is worse. Diabetes, chronic pulmonary heart disease, bronchiectasis, pulmonary bulla, hypoproteinemia are the related factors of IPA in patients with AECOPD.
Sujet(s)
Dilatation des bronches , Aspergillose pulmonaire invasive , Broncho-pneumopathie chronique obstructive , Coeur pulmonaire , Humains , Mâle , Cloque , Études rétrospectivesRÉSUMÉ
To investigate the distribution and clinical significance of nuclear dense fine speckled (DFS) pattern in various diseases. A total of 95 289 patients who received DFS tests at Peking Union Medical College Hospital from January 2019 to December 2020 were included in this study. The results of indirect immunofluorescence assay (IIF) for detection of antinuclear antibody (ANA) were evaluated. The positive rates of ANA and DFS were 39.60% (37 733/95 289) and 1.19% (1 139/95 289) respectively. The positive rate of DFS in ANA-positive patients was 3.02% (1 139/37 733). DFS and ANA positivity were significantly different among different age groups rather than gender. The positivity rate of DFS reached the peak (55.57%, 633/1 139) in young patients between 21-40 years, while positive ANA with negative DFS was mainly observed in patients between 41-60 years (37.26%, 13 636/36 594). Additionally, single ANA-positivity were mainly detected in rheumatology department (59.23%, 18 402/31 066), whereas positive DFS was more common in obstetrics and gynecology department (3.08%, 49/1 593). There were 82.88% (944/1 139) patients with positive DFS diagnosed with non-autoimmune disease (non-AID), and 19.49%(222/1 139) with dermatosis. Positive DFS with higher titer (≥1â¶320) was detected more frequently in autoimmune disease (AID) patients (5.13%, 10/195) than in non-AID patients (1.69%, 16/944) (P<0.05). The DFS pattern is rare in ANA positive patients, which is mainly observed in women between 21-49 years. High titer of DFS is prevalent in AID patients, but positive DFS is detected more in non-AID patients, especially those with dermatosis.
Sujet(s)
Maladies auto-immunes , Maladies de la peau , Protéines adaptatrices de la transduction du signal , Anticorps antinucléaires , Maladies auto-immunes/diagnostic , Femelle , Technique d'immunofluorescence indirecte/méthodes , Humains , Facteurs de transcriptionRÉSUMÉ
Objective: To investigate whether vestibular-evoked myogenic potentials(VEMPs) can be used to assess brainstem involvement in patients with Kennedy's disease (KD). Method: This was a case-control study.Twenty consecutive patients with genetically confirmed KD and 20 age-and sex-matched healthy subjects were enrolled from November 2018 to September 2020.All subjects were tested for three types of VEMPs, including cervical VEMP (c-VEMP) recorded by the sternocleidomastoid muscle (parameter:p13, n23), masseter VEMP (m-VEMP) recorded by the masseter muscle(parameter: p11), and ocular VEMP (o-VEMP) recorded by the inferior oblique muscle (parameter n10, p15).The latency of each wave, interside peak latency and interpeak latency of c-VEMP, the corrected amplitude and amplitude asymmetry ratio were recorded. Bilateral sternocleidomastoid muscle (SCMM) electromyography (EMG) was performed. The spinal cord and bulbous muscular atrophy functional rating scale (SBMAFRS) was used for assessment. Results: The mean p13 latency of c-VEMP was (15.5±1.4)ms, which was longer than that of the control group[(13.3±0.9)ms](P<0.05); the mean n23 latency was(25.5±1.4)ms, which was also longer than that of the control group[(22.5±1.0)ms] (P<0.05); the difference of bilateral p13[(2.3±0.6)ms] was significantly higher than that of the control group(P<0.05). The abnormal rates of c-, m-, o-VEMP in KD patients were 75%(15/20), 30%(6/20) and 20%(4/20), respectively. There was a significant positive correlation between c-VEMP latency and course of disease in KD patients(left: r=0.715, 0.695, right: r= 0.708, 0.715, both P<0.05). However, c-VEMP latency was negatively correlated with SBMAFRS score (left: r=-0.701, -0.694, right: r=-0.644, -0.685, both P<0.05). Abnormal rates of SCMM EMG in KD group were as follows: 15%(3/20)of patients showed spontaneous potential in resting state and 45% (9/20) of patients exhibited simple recruitment. Conclusions: The c-VEMP latency is a sensitive tool for detecting lower brainstem involvement in patients with KD, and the degree of damage increases with prolongation of disease course. The o-and m-VEMP abnormalities indicate that some KD patients develop upper brainstem damage.
Sujet(s)
Amyotrophie bulbospinale liée à l'X , Potentiels évoqués vestibulaires myogéniques , Stimulation acoustique , Tronc cérébral , Études cas-témoins , Électromyographie , HumainsRÉSUMÉ
Objective: To investigate the risk factors associated with in-hospital mortality in hospitalized patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Methods: A total of 6 668 patients hospitalized for AECOPD in seven tertiary hospitals from September 2017 to January 2021 were consecutively included, and clinical data related to medical history, laboratory tests, treatment and prognosis were collected, and patients were divided into death group and survival group according to whether they died during hospitalization. After univariate analysis, multivariate logistic regression analysis was then performed to explore the independent risk factors related to in-hospital mortality. Results: Among 6 668 patients hospitalized for AECOPD, 128 patients experienced in-hospital death, with a mortality rate of 1.9%. The mean age of the death group was (81±9) years, which was significantly older than that of the survival group ((72±11) years P<0.001). The proportion of patients in the AECOPD in-hospital death group with a combination of prolonged bed rest, hypertension, myocardial infarction within 3 months, cardiac insufficiency, chronic pulmonary heart disease, pneumonia, type 2 diabetes, venous thromboembolism (VTE), and chronic renal insufficiency was also significantly higher than in the survival group (all P<0.05) The median length of stay in the in-hospital death group was 18 d, which was significantly longer than that in the survival group (9 d, P<0.001), and the proportion of patients admitted to the ICU, receiving invasive mechanical ventilation and non-invasive mechanical ventilation was also significantly higher than that in the survival group (all P<0.05). The white blood cell count, glutamic transaminase, blood creatinine, calcitoninogen, C-reactive protein, D-dimer, N-terminal B-type natriuretic and Pseudomonas aeruginosa infection rates were significantly higher than those in the survival group (all P<0.05). Multifactorial analysis showed that age>80 years (OR=3.82, 95%CI 2.36 to 6.18, P<0.001), prolonged bed rest (OR=2.95, 95%CI: 1.79 to 4.86, P<0.001), chronic pulmonary heart disease (OR=1.85, 95%CI: 1.14 to 3.00, P=0.012), and pneumonia (OR=2.75, 95%CI: 1.65 to 4.60, P<0.001), invasive mechanical ventilation (OR=7.33, 95%CI: 4.40 to 12.21, P<0.001), noninvasive mechanical ventilation (OR=3.73, 95%CI: 2.30 to 6.04, P<0.001), anemia (OR=2.03. 95%CI: 1.21 to 3.42, P=0.008), and calcitoninogen>0.5 ng/ml (OR=2.38, 95%CI: 1.41 to 4.02, P=0.001) were independent risk factors for in-hospital mortality in patients with AECOPD. Conclusion: Advanced age (>80 years), prolonged bed rest, chronic pulmonary heart disease, pneumonia, invasive mechanical ventilation, noninvasive mechanical ventilation, anemia, and calcitoninogen>0.5 ng/ml were independent risk factors for in-hospital mortality in patients hospitalized with AECOPD.
Sujet(s)
Diabète de type 2 , Broncho-pneumopathie chronique obstructive , Sujet âgé , Sujet âgé de 80 ans ou plus , Mortalité hospitalière , Humains , Études rétrospectives , Facteurs de risqueRÉSUMÉ
Objective: To observe the application effects of a standard communication system-based continuous home remote visit mode in the management of visits to severely burned patients in the post-pandemic era of coronavirus disease 2019 (hereinafter referred to as post-pandemic era). Methods: A retrospective cohort study was conducted. A total of 69 severely burned patients who met the inclusion criteria and were admitted to the First Affiliated Hospital of Army Medical University (the Third Military Medical University) from February to December, 2020 and their 69 family members were recruited into this study. According to the difference of visit model, 33 severely burned patients who were admitted into burn intensive care unit (BICU) from February to June, 2020 and received completely restricted visits according to the requirements for epidemic prevention and control and their corresponding 33 family members were included into conventional visit group; 36 severely burned patients who were admitted into BICU from July to December, 2020 and received the standard communication system-based continuous home remote visits and their 36 corresponding family members were recruited into remote visit group. The family members in conventional visit group could only communicate with the primary nurses by telephone, while the patients and family members in remote visit group could communicate with the primary nurses, responsible doctors, rehabilitation therapists, and nutrition therapists through WeChat video call. The survey results of general information questionnaire and Hamilton Anxiety Scale (HAMA) scores of two groups of patients and their family members at BICU admission of patients, HAMA scores of the two groups of patients and their family members in the second week of BICU admission and at discharge from BICU of patients, the scores of the Visiting Effect Evaluation Scale of the two groups of patients and their family members and the scores of Chinese version of Critical Care Family Satisfaction Survey (C-CCFSS) of the two groups of family members at discharge from BICU, and the scores of Satisfaction Survey and Evaluation Scale During Hospitalization of patients within the first week after the discharge of patients from BICU were compared. Data were statistically analyzed with chi-square test, Fisher's exact probability test, and Mann-Whitney U test. Results: In remote visit group, there were 29 males and 7 females in patients, aged 48 (34, 53) years, and 15 males and 21 females in family members, aged 45 (30, 48) years. In conventional visit group, there were 24 males and 9 females in patients, aged 49 (38, 54) years, and 9 males and 24 females in family members, aged 44 (35, 48) years. At BICU admission of patients, the HAMA scores of the two groups of patients and family members were both similar (P>0.05). The total HAMA scores of patients and family members in remote visit group were significantly lower than those in conventional visit group in the second week when the patients were admitted to BICU (Z=-3.195, -3.018, P<0.01) and discharged from BICU (Z=-2.118, -2.380, P<0.05). At discharge from BICU of patients, the scores of each dimension in Visiting Effect Evaluation Scale of the patients in the two groups were similar (P>0.05); while scores of 3 dimensions including patient safety information, diagnosis and treatment quality information, and psychological support information in Visiting Effect Evaluation Scale of family members in remote visit group were significantly higher than those in conventional visit group (Z=-2.372, -2.209, -2.174, P<0.05), and only the scores of visit perception of family members were close to those in conventional visit group (P>0.05). At discharge from BICU of patients, the C-CCFSS scores of the family members in remote visit group was 99 (98, 108), which were significantly higher than 98 (97, 100) in conventional visit group (Z=-2.545, P<0.05). Within the first week after the discharge of patients from BICU, the scores of Satisfaction Survey and Evaluation Scale During Hospitalization of patients in remote visit group were 99 (98, 100), which were significantly higher than 96 (94, 98) in conventional visit group (Z=-5.213, P<0.01). Conclusions: In the management of visits to severely burned patients in the post-pandemic era, application of the standard communication system-based continuous home remote visit mode can improve the visit effect and satisfaction, and effectively alleviate the anxiety of patients and their family members.
Sujet(s)
COVID-19 , Pandémies , Communication , Femelle , Humains , Mâle , Études rétrospectives , SARS-CoV-2RÉSUMÉ
Objective: To study the clinical application effect of modified nasopharyngeal swab sampling for 2019 novel coronavirus nucleic acid detection. Methods: This study covered the period from January 14 to March 1, 2020.The supine position method and the protective face screen were used to collect nasopharyngeal swabs from February 24 onwards, before which, the nasopharyngeal swabs were collected by sitting position method. All the patients who were diagnosed with suspected/confirmed 2019 novel coronavirus infection were admitted from February 19 with the nasopharyngeal swabs collected outside the hospital before admission. (1) Thirty-four swabbing operators meeting the inclusion criteria of the study were recruited in this retrospective cohort study. They were grouped according to the collection method of nasopharyngeal swabs. Sixteen operators of Wuhan Taikang Tongji Hospital who applied the supine position method and the protective face screen were included in supine position method+ protective face screen group (15 males and 1 female, aged 34-49 years); 18 operators (12 from the First Affiliated Hospital of Army Medical University (the Third Military Medical University), 1 from Wuhan Jiangxia Mobile Cabin Hospital, 5 from the East District of People's Hospital of Wuhan University) who applied the traditional sitting position method were included in sitting position method group (2 males and 16 females, aged 25-49 years). In supine position method+ protective face screen group, when collecting sample, the patient lay flat and wore a special protective face screen for nasopharyngeal swab sampling, with neck slightly extending and face turning to the opposite side of the operator about 10°. The self-designed questionnaire was used to investigate the cooperation, the incidence of nausea, coughing, sneezing, and struggling of patients evaluated by the operators, the operation time for a single swab sample, the fear of operation and the perceived exposure risk of operators in the two groups. (2) Sixty-five patients (22 males and 43 females, aged 25-91 years) admitted to Wuhan Taikang Tongji Hospital who successively received the sitting position method and supine position method+ protective face screen for nasopharyngeal swabs sampling and with complete nucleic acid detection results were included. The positive rates of nucleic acid detection by the two sampling methods of nasopharyngeal swabs of the patients were statistically analyzed. (3) Forty-one patients who could express their feelings accurately were selected out of those 65 patients (12 males and 29 females, aged 27-83 years). The comfort of patients in the process of sampling by the two methods was investigated. (4) Thirty-four patients (10 males and 24 females, aged 25-83 years) with two or more consecutive negative results of nucleic acid detection of nasopharyngeal swabs by sitting position method were selected from the above 65 patients. The positive rate of nucleic acid detection of nasopharyngeal swab of patients by supine position method+ protective face screen, i. e. negative to positive rate was statistically analyzed. Data were statistically analyzed with t test, Wilcoxon signed rank test, and chi-square test. Results: (1) Compared with those of sitting position method group, the cooperation score of patients evaluated by the operators in supine position method+ protective face screen group was significantly higher (Z=-4.928, P<0.01), the incidence of nausea, choking cough, sneezing, and struggling of patients evaluated by the operators, and the fear of operation score and the perceived exposure risk score of operators in supine position method+ protective face screen group were significantly lower (Z=-5.071, -5.046, -4.095, -4.397, -4.174, -5.049, P<0.01), and the operation time for a single swab sample in supine position method+ protective face screen group was significantly longer (t=223.17, P<0.01). (2) The positive rate of nucleic acid detection of nasopharyngeal swabs by supine position method+ protective face screen was 60.00% (39/65), which was obviously higher than 41.54% (27/65) by sitting position method (χ(2)=4.432, P<0.05). (3) The comfort score of the 41 patients during nasopharyngeal swabs sampling by supine position method+ protective face screen was significantly higher than that by sitting position method (Z=-5.319, P<0.01). (4) Of the 34 patients with two or more consecutive negative results of nucleic acid detection of nasopharyngeal swabs by sitting position method, the rate of negative to positive of nucleic acid detection was 26.47% (9/34) after sampling by supine position method+ protective face screen. Conclusions: Compared with the traditional sitting position method, detection of 2019 novel coronavirus nucleic acids of nasopharyngeal swabs collected by supine method combined with protective face screen is worth promoting, because of its better comfort of patients, low exposure risk for operators, in addition to reducing in the false negative result to some extent, which may help reduce false recurrence of discharged patients.
Sujet(s)
Betacoronavirus , Infections à coronavirus , Pandémies , Pneumopathie virale , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , COVID-19 , Femelle , Humains , Mâle , Adulte d'âge moyen , Acides nucléiques , Études rétrospectives , SARS-CoV-2RÉSUMÉ
The magnetic vortex, as one of the most interesting magnetic solitons, has attracted great interest over the past two decades. A fast and reliable method to switch vortex polarity and chirality is one of the key issues for various applications. Based on micromagnetic simulation, here we report a fast, low energy cost and deterministic switching of a vortex core, by the designing of a notch structure in disks and the use of out-of-plane current geometry. We demonstrate that with such a design, the multiple switching problems found in notch disk systems can be avoided. Furthermore, the switching time can be reduced by more than 50% compared with disks without notches.
RÉSUMÉ
Objective: To investigate the efficacy of simple device of continuous positive airway pressure (CPAP) in the treatment of obstructive sleep apnea (OSA). Methods: A double-blind study was performed on 53 OSA patients who received overnight simple CPAP and traditional CPAP in a random order during polysomnography. Pressure for CPAP treatment was manual titrated. The sleep apnea hypopnea index (AHI), arousal index (ArI), Oxygen desaturation Index (ODI), sleep structure and the preference for CPAP devices of the patients were observed. Results: AHI, ArI, ODI decreased significantly from 35.7 (18.1, 58.8)/h, (29.4±18.6)/h, 22.0 (13.9, 47.3)/h before treatment to 1.7 (0.7, 4.4)/h, (11.5±5.1) /h and 1.3 (0.4, 3.6)/h after treatment with simple CPAP, respectively (all P<0.05). There was no statistically significant difference in residual AHI [1.7 (0.7, 4.4)/h vs 1.9 (0.8, 4.3)/h], ArI [(11.5±5.1)/h vs (10.5±4.4)/h] and ODI [1.3 (0.4, 3.6)/h vs 1.3 (0.5, 4.2)/h] between treatment with simple CPAP and traditional CPAP (all P>0.05). The amount of time spent on deep sleep (stage â ¢) and rapid eye movement (REM) increased significantly from (6.2+ 6.6)% and (16.3+ 7.0)% before treatment to (11.7±8.5)% and (20.7±5.1)% during treatment with simple CPAP and (11.4±8.6)% and (20.9±5.0)% with traditional CPAP, respectively. The patients had no clear preference for two CPAP devices. Conclusion: Traditional CPAP can be replaced by the simple CPAP to treat patients with OSA.
Sujet(s)
Ventilation en pression positive continue , Syndrome d'apnées obstructives du sommeil , Éveil , Méthode en double aveugle , Humains , PolysomnographieRÉSUMÉ
Magnetic proximity effect between two magnetic layers is an important focus of research for discovering new physical properties of magnetic systems. Antiferromagnets (AFMs) are fundamental systems with magnetic ordering and promising candidate materials in the emerging field of antiferromagnetic spintronics. However, the magnetic proximity effect between antiferromagnetic bilayers is rarely studied because detecting the spin orientation of AFMs is challenging. Using X-ray linear dichroism and magneto-optical Kerr effect measurements, we investigated antiferromagnetic proximity effects in epitaxial CoO/NiO/MgO(001) systems. We found the antiferromagnetic spin of the NiO underwent a spin reorientation transition from in-plane to out-of-plane with increasing NiO thickness, with the existence of vertical exchange spring spin alignment in thick NiO. More interestingly, the Néel temperature of the CoO layer was greatly enhanced by the adjacent NiO layer, with the extent of the enhancement closely dependent on the spin orientation of NiO layer. This phenomenon was attributed to different exchange coupling strengths at the AFM/AFM interface depending on the relative spin directions. Our results indicate a new route for modifying the spin configuration and ordering temperature of AFMs through the magnetic proximity effect near room temperature, which should further benefit the design of AFM spintronic devices.
RÉSUMÉ
We compared the physiological work, judged by oxygen uptake, esophageal pressure swing and diaphragm electromyography, elicited by Tai Chi compared with that elicited by constant rate treadmill walking at 60% of maximal load in eleven patients with COPD (Mean FEV1 61% predicted, FEV1/FVC 47%). Dynamic hyperinflation was assessed by inspiratory capacity and twitch quadriceps tension (TwQ) elicited by supramaximal magnetic stimulation of the femoral nerve was also measured before and after both exercises. The EMGdi and esophageal pressure at the end of exercise were similar for both treadmill exercise and Tai Chi (0.109±0.047 mV vs 0.118±0.061 mV for EMGdi and 22.3±7.1 cmH2O vs 21.9±8.1 cmH2O for esophageal pressure). Moreover the mean values of oxygen uptake during Tai Chi and treadmill exercise did not differ significantly: 11.3 ml/kg/min (51.1% of maximal oxygen uptake derived from incremental exercise) and 13.4 ml/kg/min (52.5%) respectively, p>0.05. Respiratory rate during Tai Chi was significantly lower than that during treadmill exercise. Both Tai Chi and treadmill exercise elicited a fall in IC at end exercise, indicating dynamic hyperinflation, but this was statistically significant only after treadmill exercise. TwQ decreased significantly after Tai Chi but not after treadmill. We conclude that Tai Chi constitutes a physiologically similar stimulus to treadmill exercise and may therefore be an acceptable modality for pulmonary rehabilitation which may be culturally more acceptable in some parts of the world.
Sujet(s)
Broncho-pneumopathie chronique obstructive/physiopathologie , Broncho-pneumopathie chronique obstructive/rééducation et réadaptation , Tai Chi/méthodes , Sujet âgé , Muscle diaphragme/physiologie , Électromyographie , Traitement par les exercices physiques , Volume expiratoire maximal par seconde , Humains , Magnétothérapie , Mâle , Adulte d'âge moyen , Contraction musculaire , Consommation d'oxygène , Capacité pulmonaire totale , Résultat thérapeutiqueRÉSUMÉ
In order to compare the effects of weathering on two types of mixed oil, simulated weathering experiments were performed. The first sample was a mixture of two fresh oils and the second sample was a mixture of one fresh oil and another oil sample that had undergone a serious weathering process. Comparative studies evaluated decay rates and changes in diagnostic ratios of some fingerprinting biomarkers. Results showed that the mixing process affected the weathering rate of some compounds in the oils and also that certain diagnostic ratios are more suitable for estimating mixing proportions. A Pr/n-C17 versus Ph/n-C18 plot can be used to identify the end-numbers of mixed oils and the (C13+C14)/(C25+C26) ratio is a useful diagnostic ratio to detect the degree of weathering. Finally, hopane, sterane, and alkylated PAH fingerprints were found to give useful insights about the sources of the mixed oils.
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Modèles chimiques , Huiles/composition chimique , Polluants chimiques de l'eau/composition chimique , Marqueurs biologiques , Chromatographie gazeuse-spectrométrie de masse , Hydrocarbures aromatiques polycycliques/composition chimique , Temps (météorologie)RÉSUMÉ
OBJECTIVE: Bone marrow-derived mesenchymal stem cells (MSCs) can serve as a vehicle for gene therapy. FGF2 (basic fibroblast growth factor) is a multifunctional growth factor and exhibits diverse function in different cell types, it also has pleiotropic effects in different tissues and organs, including potent angiogenic effects and an important role in the differentiation and function of the central nervous system. We hypothesized that MSC-based FGF2 gene therapy might be a potential therapeutic approach for lipopolysaccharide (LPS)-induced lung injury. MATERIALS AND METHODS: MSCs were isolated from 6 week-old inbred male mice and transduced with the FGF2 gene, using a lentivirus vector. RESULTS: In the in vivo mouse model, the LPS-induced lung injury was markedly alleviated in the group treated with MSCs carrying FGF2 (MSCs-FGF2), compared with groups treated with MSCs alone. The histopathological index of LPS-induced lung injury was improved after MSCs-based FGF2 gene treatment. The MSCs-FGF2 administration also reduced the level of inflammatory cytokines. CONCLUSIONS: These results suggest that MSCs and FGF2 have a synergistic role in the treatment of LPS-induced lung injury.
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Lésion pulmonaire aigüe/thérapie , Facteur de croissance fibroblastique de type 2/génétique , Thérapie génétique/méthodes , Transplantation de cellules souches mésenchymateuses/méthodes , Lésion pulmonaire aigüe/induit chimiquement , Lésion pulmonaire aigüe/génétique , Animaux , Femelle , Lipopolysaccharides , Mâle , Cellules souches mésenchymateuses/physiologie , Souris , Souris de lignée C57BL , Répartition aléatoireRÉSUMÉ
Melanoma has traditionally been viewed as a radioresistant cancer. However, recent studies suggest that under certain clinical circumstances, radiotherapy may play a significant role in the treatment of melanoma. Previous studies have demonstrated that telomere length is a hallmark of radiosensitivity. The newly discovered mammalian CTC1STN1-TEN1 (CST) complex has been demonstrated to be an important telomere maintenance factor. In this study, by establishing a radiosensitive/radioresistant human melanoma cell model, MDA-MB-435/MDA-MB435R, we aimed to investigate the association of CTC1 expression with radiosensitivity in human melanoma cell lines, and to elucidate the possible underlying mechanisms. We found that CTC1 mRNA and protein levels were markedly increased in the MDA-MB435R cells compared with the MDA-MB435 cells. Moreover, the downregulation of CTC1 enhanced radiosensitivity, induced DNA damage and promoted telomere shortening and apoptosis in both cell lines. Taken together, our findings suggest that CTC1 increases the radioresistance of human melanoma cells by inhibiting telomere shortening and apoptosis. Thus, CTC1 may be an attractive target gene for the treatment of human melanoma.