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1.
Virulence ; 15(1): 2327096, 2024 12.
Article in English | MEDLINE | ID: mdl-38466143

ABSTRACT

Legionella pneumophila (L. pneumophila) is a prevalent pathogenic bacterium responsible for significant global health concerns. Nonetheless, the precise pathogenic mechanisms of L. pneumophila have still remained elusive. Autophagy, a direct cellular response to L. pneumophila infection and other pathogens, involves the recognition and degradation of these invaders in lysosomes. Histone deacetylase 6 (HDAC6), a distinctive member of the histone deacetylase family, plays a multifaceted role in autophagy regulation. This study aimed to investigate the role of HDAC6 in macrophage autophagy via the autophagolysosomal pathway, leading to alleviate L. pneumophila-induced pneumonia. The results revealed a substantial upregulation of HDAC6 expression level in murine lung tissues infected by L. pneumophila. Notably, mice lacking HDAC6 exhibited a protective response against L. pneumophila-induced pulmonary tissue inflammation, which was characterized by the reduced bacterial load and diminished release of pro-inflammatory cytokines. Transcriptomic analysis has shed light on the regulatory role of HDAC6 in L. pneumophila infection in mice, particularly through the autophagy pathway of macrophages. Validation using L. pneumophila-induced macrophages from mice with HDAC6 gene knockout demonstrated a decrease in cellular bacterial load, activation of the autophagolysosomal pathway, and enhancement of cellular autophagic flux. In summary, the findings indicated that HDAC6 knockout could lead to the upregulation of p-ULK1 expression level, promoting the autophagy-lysosomal pathway, increasing autophagic flux, and ultimately strengthening the bactericidal capacity of macrophages. This contributes to the alleviation of L. pneumophila-induced pneumonia.


Subject(s)
Legionella pneumophila , Legionella , Legionnaires' Disease , Pneumonia , Animals , Mice , Autophagy , Histone Deacetylase 6/genetics , Legionella pneumophila/genetics , Legionnaires' Disease/genetics , Macrophages
2.
Materials (Basel) ; 16(20)2023 Oct 19.
Article in English | MEDLINE | ID: mdl-37895756

ABSTRACT

In order to improve the utilization rate of coal gangue and expand the application range of coal gangue concrete (CGC), a certain proportion of steel fiber was added to the concrete, and the freeze-thaw cycles (FTCs) and flexural tests were used to explore the effects of different mass replacement rates of coal gangue (0%, 25%, 50%, 75%, and 100%) and different proportions of the volumetric blending of the steel fiber (0%, 0.8%, 1.0%, and 1.2%) on the frost resistance of steel fiber-reinforced CGC (SCGC). The governing laws of mass loss rate, relative dynamic elastic modulus and load-midspan deflection curve were obtained on the base of the analysis of testing results. The damage mechanisms of the SCGC under the FTCs were analyzed using the results of scanning electron microscopy (SEM). Based on the Lemaitre's strain equivalence principle and Krajcinovic's vector damage theory, a damage evolution model of the SCGC under the FTCs was established by introducing the damage variable of the SCGC satisfying Weibull distribution. The results show an increasing mass loss rate of the SCGC and a decreasing relative dynamic elastic modulus with an increasing mass replacement rate of coal gangue. The proper content of the steel fiber can reduce the mass loss rate of concrete by 10~40% and the relative loss rate of dynamic elastic modulus of concrete by 2~8%, thus significantly improving the ductility and toughness of the concrete. The established damage evolution model is well validated by the experimental results, which further help to improve the modelling accuracy. This study provides key experimental data and a theoretical basis for a wider range of proper utilization of coal gangue in cold regions.

3.
Heliyon ; 8(11): e11252, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36387482

ABSTRACT

This paper solves the technical difficulties of the capillary water rising height of the construction waste improved expansive soil subgrade (CWS), analyses the capillary water rising mechanism of the construction waste improved expansive soil subgrade cushion and evaluates the improvement effect of the improved cushion by comparing different working conditions with simulation software. The analysis results show that: (1) a reasonable ratio of the improved subgrade bed can effectively improve the porosity of the cushion layer, thus effectively inhibiting capillary water rising height. (2) the practical improvement of the thickness of the cushion layer can slow the matrix suction effect of expansive soil, (3) the construction waste had a more significant influence on the particle gradation for the capillary water rise, poor grading cushion layer has a significant influence on the capillary water rise, (4) the construction waste particles in the improved graded cushion of construction waste have strong water absorption, which improves the matrix suction effect of expansive soil. (5) Through experiments and simulation tests, this paper concludes that the optimal grade subgrade bedding of construction waste expansive soil is of specific theoretical value and practical significance for developing the construction waste material transformation subgrade. Keyword: Construction Waste, the capillary water rise mechanism, well-graded CWS.

4.
World J Clin Cases ; 10(20): 7045-7053, 2022 Jul 16.
Article in English | MEDLINE | ID: mdl-36051134

ABSTRACT

BACKGROUND: Atherosclerosis is one of the main causes of coronary artery ostial lesions seen clinically. Secondary coronary artery ostial lesions are rare, and cases reported previously were associated with syphilitic vasculitis and aortic dissection. Here, we report three rare cases of secondary coronary ostial lesions. Due to their rareness, these lesions can easily be neglected, which may lead to misdiagnosis and missed diagnosis. CASE SUMMARY: We present three patients with acute myocardial infarction and unstable angina caused by secondary coronary artery ostial lesions. In Case 1, coronary angiography (CAG) revealed 90% stenosis of the left main coronary ostium. Chest contrast computed tomography (CT) suggested thymic carcinoma invading the left main coronary ostium. Coronary artery bypass grafting and tumor resection were performed. In Case 2, echocardiography revealed a sinus of Valsalva aneurysm (SVA)-like dilatation. CAG showed a right coronary sinus giant aneurysm and complete obstruction of the right coronary artery (RCA) ostium. Aortic contrast CT confirmed these findings. The Bentall procedure was performed. In Case 3, CT CAG identified an anomalous origin of the right coronary artery (AORCA) from the left sinus of Valsalva coursing between the aorta and pulmonary trunk, causing severe RCA ostium stenosis by compression. Surgical correction of the AORCA was performed. CONCLUSION: The cases reported here suggest that we should consider other causes of coronary ostial lesions other than atherosclerosis.

5.
Sci Total Environ ; 776: 145911, 2021 Jul 01.
Article in English | MEDLINE | ID: mdl-33647655

ABSTRACT

Dissolved organic carbon (DOC) and nitrogen (N) play essential roles in global C and N cycles. To address the possible role of DOC and N in precipitation and enrich the related global database, the characteristics of DOC and N in precipitation were investigated in a typical remote permafrost region (upper Heihe River Basin) of the northern Tibetan Plateau (TP) from February 2019 to March 2020. The results demonstrated that the average DOC and total dissolved N (TDN) concentrations in the precipitation were 1.41 ± 1.09 µg mL-1 and 0.84 ± 0.48 µg mL-1, respectively, with relatively lower concentrations in the summer. The annual DOC and TDN fluxes were estimated to be 6.42 kg ha-1 yr-1 and 3.39 kg ha-1 yr-1, respectively, indicating that precipitation was a significant factor in C and N deposition. The light-absorbing properties of precipitation DOC from the SUVA254 and spectral slope revealed that precipitation DOC containing more aromatic components and lower molecular weights mostly was present during the summer; the mass cross-section (at the wavelength of 365 nm) ranged 0.26-1.84 m2 g-1, suggesting the potential impact of DOC on climatic forcing in the area. The principal component analysis combined with air mass backward trajectories indicated that the air masses from west Siberia, Central Asia, and northwestern China most significantly influenced the precipitation C and N in the study area. The WRF-Chem simulations and aerosol vertical distributions further illustrated the air mass transport pathways, demonstrating that dust and anthropogenic emissions could be transported over the studied area by westerlies and monsoonal winds. In the study basin, the precipitation deposition of DOC and N contributed largely to the riverine DOC and N exportation during the summer and had potential ecological effects. These results highlight the importance of DOC and N deposition from precipitation in the northern TP.

6.
Plants (Basel) ; 9(11)2020 Oct 28.
Article in English | MEDLINE | ID: mdl-33126554

ABSTRACT

Degradation of permafrost with a thin overlying active layer can greatly affect vegetation via changes in the soil water and nutrient regimes within the active layer, while little is known about the presence or absence of such effects in areas with a deep active layer. Here, we selected the northeastern Qinghai-Tibet Plateau as the study area. We examined the vegetation communities and biomass along an active layer thickness (ALT) gradient from 0.6 to 3.5 m. Our results showed that plant cover, below-ground biomass, species richness, and relative sedge cover declined with the deepening active layer, while the evenness, and relative forb cover showed a contrary trend. The vegetation indices and the dissimilarity of vegetation composition exhibited significant changes when the ALT was greater than 2.0 m. The vegetation indices (plant cover, below-ground biomass, evenness index, relative forb cover and relative sedge cover) were closely associated with soil water content, soil pH, texture and nutrient content. Soil water content played a key role in the ALT-vegetation relationship, especially at depths of 30-40 cm. Our results suggest that when the ALT is greater than 2.0 m, the presence of underlying permafrost still benefits vegetation growth via maintaining adequate soil water contents at 30-40 cm depth. Furthermore, the degradation of permafrost may lead to declines of vegetation cover and below-ground biomass with a shift in vegetation species.

7.
Int J Cardiol ; 270: 268-272, 2018 Nov 01.
Article in English | MEDLINE | ID: mdl-29945807

ABSTRACT

BACKGROUND: Intramural hematomas (IMHs) are reported to dynamically evolve into different clinical outcomes ranging from regression to aortic rupture, but no practice guidelines are available in China. OBJECTIVE: To determine the evolution of IMHs after long-term follow-up and to identify the predictive factors of IMH outcomes in the Chinese population. METHODS: A total of 123 IMH patients with clinical and imaging follow-up data were retrospectively studied. The primary endpoints were aortic disease-related death, aortic dissection, penetrating aortic ulcer (PAU), thickening of the aortic hematoma and aortic complications requiring surgical or endovascular treatment. RESULTS: All 123 IMH patients were monitored clinically. The follow-up duration ranged from 1.4 to 107 months (median, 20 months). Thirty-nine patients had type A IMH, and 84 had type B. The multivariate analysis showed that a baseline MAD ≥ 44.75 mm (2.9% vs 61.4%, P < 0.001) and acute PAUs (2.9% vs 34.1%, P = 0.008) were independent predictors of aorta-related events. CONCLUSIONS: Medication and short-term imaging are recommended for Chinese IMH patients with a hematoma thickness < 10.45 mm and a baseline MAD < 44.75 mm. Rigorous medical observation should also be performed during the acute phase of IMH.


Subject(s)
Aortic Dissection/diagnostic imaging , Aortic Dissection/epidemiology , Aortic Rupture/diagnostic imaging , Aortic Rupture/epidemiology , Hematoma/diagnostic imaging , Hematoma/epidemiology , Aged , China/epidemiology , Female , Follow-Up Studies , Humans , Male , Middle Aged , Retrospective Studies , Time Factors
8.
Chin Med J (Engl) ; 131(12): 1430-1435, 2018 Jun 20.
Article in English | MEDLINE | ID: mdl-29893359

ABSTRACT

BACKGROUND: The prevalence, presentation, management, and prognosis of coronary heart disease differ according to sex. Greater understanding on the differences between men and women with acute aortic dissection (AAD) is needed. We aimed to investigate whether sex disparities are found in patients with AAD, and to study sex differences in complications, mortality in-hospital, and long-term. METHODS: We included 884 patients enrolled in our institute between June 2002 and May 2016. Considering psychosocial factors, treatments, and the outcomes in men versus those in women with AAD, we explored the association of sex with psychosocial characteristics and mortality risk. For categorical variables, significant differences between groups were assessed with the Chi-square test or Fisher's exact test, and continuous parameters were assessed with Student's t-test. Univariate and stratified survival statistics were computed using Kaplan-Meier analysis. RESULTS: A total of 884 patients (76.1% male, mean age 51.4 ± 11.8 years) were included in this study. There were fewer current smokers in female compared with male (17.5% vs. 67.2%, χ2 = 160.06, P < 0.05). The percentage of men who reported regular alcohol consumption was significantly higher than that in women (40.6% vs. 3.8%, χ2 = 100.18, P < 0.05). About 6.2% (55 of 884) of patients with AAD died before vascular or endovascular surgery was performed, 34.4% (304 of 884) of patients underwent surgical procedures, and 52.7% (466 of 884) and 12.8% (113 of 884) of patients received endovascular treatment and medication. Postoperative mortality similar (6.0% vs. 5.6%, respectively, χ2 = 0.03, P = 0.91) between men and women. Follow-up was completed in 653 of 829 patients (78.8%). Adjustment for age, history of coronary disease, hypertension, smoking and drinking, Type A and use of beta-blocker, angiotensin II receptor blockers, angiotensin converting enzyme (ACE) inhibitor, calcium-channel blockers and statins by multivariate logistic regression analysis suggested that age (odds ratios [OR s], 1.04; 95% confidence interval [CI], 1.01-1.07; P < 0.05), using of calcium-channel blockers (OR, 0.37; 95% CI, 0.18-0.74; P < 0.05), at discharge were independent predictors of late mortality, ACE inhibitors (OR, 1.91; 95% CI, 1.03-3.54; P = 0.04) was independent risk factor of late mortality. CONCLUSIONS: In Chinese with AAD, sex is not independently associated with long-term clinical outcomes. Age, the intake of calcium-channel blockers at discharge might help to improve long-term outcomes.


Subject(s)
Aortic Dissection/diagnosis , Aortic Dissection/drug therapy , Adult , Age Factors , Aortic Dissection/pathology , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Calcium Channel Blockers/therapeutic use , Female , Humans , Hypertension/diagnosis , Hypertension/drug therapy , Hypertension/pathology , Kaplan-Meier Estimate , Logistic Models , Male , Middle Aged , Odds Ratio , Prognosis , Retrospective Studies , Risk Factors , Sex Factors , Treatment Outcome
9.
Sci Total Environ ; 618: 1033-1045, 2018 Mar 15.
Article in English | MEDLINE | ID: mdl-29092743

ABSTRACT

Ecology, hydrology, and natural resources in the source areas of the Yangtze and Yellow rivers (SAYYR) are closely linked to interactions between climate and permafrost. However, a comprehensive study of the interactions is currently hampered by sparsely- and unevenly-distributed monitoring sites and limited field investigations. In this study, the thermal regime of warm-dry permafrost in the SAYYR was systematically analyzed based on extensive data collected during 2010-2016 of air temperature (Ta), ground surface temperature (GST) and ground temperature across a range of areas with contrasting land-surface characteristics. Mean annual Ta (MAAT) and mean annual GST (MAGST) were regionally averaged at -3.19±0.71°C and -0.40±1.26°C. There is a close relationship between GST and Ta (R2=0.8477) as obtained by a linear regression analysis with all available daily averages. The mean annual temperature at the bottom of the active layer (TTOP) was regionally averaged at -0.72±1.01°C and mostly in the range of -1.0°C and 0°C except at Chalaping (~-2.0°C). Surface offset (MAGST-MAAT) was regionally averaged at 2.54±0.71°C. Thermal offset (TTOP-MAGST) was regionally averaged at -0.17±0.84°C, which was generally within -0.5°C and 0.5°C. Relatively consistent thermal conductivity between the thawed and frozen states of the soils may be responsible for the small thermal offset. Active layer thickness was generally smaller at Chalaping than that on other parts of the QTP, presumably due to smaller climatic continentality index and the thermal dampening of surface temperature variability under the presence of dense vegetation and thick peaty substrates. We conclude that the accurate mapping of permafrost on the rugged elevational QTP could be potentially obtained by correlating the parameters of GST, thermal offset, and temperature gradient in the shallow permafrost.

10.
Chin Med J (Engl) ; 130(19): 2321-2325, 2017 Oct 05.
Article in English | MEDLINE | ID: mdl-28937039

ABSTRACT

BACKGROUND: Acute aortic dissection is known as the most dangerous aortic disease, with management and prognosis determined as the disruption of the medial layer provoked by intramural bleeding. The objective of this study was to evaluate the safety and necessity of antiplatelet therapy on patients with Stanford Type B aortic dissection (TBAD) who underwent endovascular aortic repair (EVAR). METHODS: The present study retrospectively analyzed 388 patients with TBAD who underwent EVAR and coronary angiography. The primary outcomes were hemorrhage, death, endoleak, recurrent dissection, myocardial infarction, and cerebral infarction in patients with and without aspirin antiplatelet therapy at 1 month and 12 months. RESULTS: Of those 388 patients, 139 (35.8%) patients were treated with aspirin and 249 (64.2%) patients were not treated with aspirin. Patients in the aspirin group were elderly (57.0 ± 10.3 years vs. 52.5 ± 11.9 years, respectively, χ2 = 3.812, P < 0.001) and had more hypertension (92.1% vs. 83.9%, respectively, χ2 = 5.191, P = 0.023) and diabetes (7.2% vs. 2.8%, respectively, χ2 = 4.090, P = 0.043) than in the no-aspirin group. Twelve patients (aspirin group vs. no-aspirin group; 3.6% vs. 2.8%, respectively, χ2 = 0.184, P = 0.668) died at 1-month follow-up, while the number was 18 (4.6% vs. 5.0%, respectively, χ2 = 0.027, P = 0.870) at 12-month follow-up. Hemorrhage occurred in 1 patient (Bleeding Academic Research Consortium [BARC] Type 2) of the aspirin group, and 3 patients (1 BARC Type 2 and 2 BARC Type 5) in the no-aspirin group at 1-month follow-up (χ2 = 0.005, P = 0.944). New hemorrhage occurred in five patients in the no-aspirin group at 12-month follow-up. Three patients in the aspirin group while five patients in the no-aspirin group had recurrent dissection for endoleak at 1-month follow-up (2.3% vs. 2.2%, respectively, χ2 = 0.074, P = 0.816). Four patients had new dissection in the no-aspirin group at 12-month follow-up (2.3% vs. 3.8%, respectively, χ2 = 0.194, P = 0.660). Each group had one patient with myocardial infarction at 1-month follow-up (0.8% vs. 0.4%, respectively, χ2 = 0.102, P = 0.749) and one more patient in the no-aspirin group at 12-month follow-up. No one had cerebral infarction in both groups during the 12-month follow-up. In the percutaneous coronary intervention (PCI) subgroup, 44 (31.7%) patients had taken dual-antiplatelet therapy (DAPT, aspirin + clopidogrel) and the other 95 (68.3%) patients had taken only aspirin. There was no significant difference in hemorrhage (0% vs. 1.1%, respectively, χ2 = 0.144, P = 0.704), death (4.8% vs. 4.5%, respectively, χ2 = 0.154, P = 0.695), myocardial infarction (2.4% vs. 0%, respectively, χ2 = 0.144, P = 0.704), endoleak, and recurrent dissection (0% vs. 3.4%, respectively, χ2 = 0.344, P = 0.558) between the two groups at 12-month follow-up. CONCLUSIONS: The present study indicated that long-term oral low-dose aspirin was safe for patients with both TBAD and coronary heart disease who underwent EVAR. For the patients who underwent both EVAR and PCI, DAPT also showed no increase in hemorrhage, endoleak, recurrent dissection, death, and myocardial infarction.


Subject(s)
Coronary Disease/drug therapy , Coronary Disease/therapy , Platelet Aggregation Inhibitors/adverse effects , Platelet Aggregation Inhibitors/therapeutic use , Adult , Aged , Aspirin/adverse effects , Aspirin/therapeutic use , Clopidogrel , Coronary Angiography , Coronary Disease/diagnostic imaging , Female , Hemorrhage/etiology , Humans , Male , Middle Aged , Myocardial Infarction/diagnostic imaging , Myocardial Infarction/etiology , Percutaneous Coronary Intervention/adverse effects , Retrospective Studies , Risk Factors , Ticlopidine/adverse effects , Ticlopidine/analogs & derivatives , Ticlopidine/therapeutic use
11.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 8): m1018-9, 2009 Jul 31.
Article in English | MEDLINE | ID: mdl-21583314

ABSTRACT

The asymmetric unit of the title complex, {[AgEr(C(5)H(3)N(2)O(2))(2)(C(2)O(4))]·H(2)O}(n), contains one Er(III) atom, one Ag(I) atom, two pyrazine-2-carboxyl-ate (pyc) ligands, two half oxalate ligands (each lying on an inversion center) and one uncoordinated water mol-ecule. The Er(III) atom is coordinated by two O atoms and two N atoms from two pyc ligands, one O atom from a third pyc ligand and four O atoms from two oxalate ligands in a distorted monocapped square-anti-prismatic geometry. The Ag(I) atom is coordinated by two N atoms from two pyc ligands, one O atom from a third pyc ligand and one O atom from one oxalate ligand. The crystal structure exhibits a three-dimensional heterometallic polymeric network. O-H⋯O hydrogen bonding between the uncoordinated water mol-ecule and carboxyl-ate O atoms is observed.

12.
Zhonghua Fu Chan Ke Za Zhi ; 44(12): 892-7, 2009 Dec.
Article in Chinese | MEDLINE | ID: mdl-20193414

ABSTRACT

OBJECTIVE: To investigate high risk human papillomavirus (HR-HPV) prevalence among married women in Beijing and to study the high risk factors. METHODS: During March 2007 to September 2008, a total of 6185 married women sampled from 137 communities in 12 districts were screened by HR-HPV DNA test and cytological test. The interview was carried out with unified questionnaires. The database was set up and twice entered in EpiData 3.0. After checked up, the data were analyzed in SPSS 15.0. RESULTS: (1) The HR-HPV infection rate was 9.89%. The HR-HPV infection rate of the city zone, the suburb and the exurb were 9.34%, 10.51% and 9.51% (P > 0.05). The HR-HPV infection rate of the native and the outlander were 9.53%, 11.30% (P < 0.05). (2) The age distribution of HR-HPV infection was that the rate was around 10% among 25 to 44 age groups, which was the highest (11.21%) in 30 to 34 age group; then the rate was descended as the age raising, the rate of 50 to 54 age group was the lowest (7.78%). (3) Multiple logistic regression showed that the related risk factors of HR-HPV infection mainly included 1000 RMB and above of family income per person per month, possessing more than 1 sexual partner of her husband, outlander and high levels of education. (4) The prevalence of cervical intraepithelial neoplasia (CIN) in HR-HPV positive group was significantly higher than that in HR-HPV negative group (29.76% vs 3.32%, P < 0.01). CONCLUSIONS: (1) The HR-HPV infection rate among aged 25 to 54 years was 9.9% and there was no significant difference in area distribution. (2) The high risk population which should strengthen screening was the married bearing-age women with high level of family income, outlander, high levels of education and her husband possessing more than 1 sexual partner. (3) HR-HPV infection is the main risk factor for CIN and cervical cancer, while does not provide a causal relationship with them. The high risk population should be checked regularly to understand the development of HR-HPV infection and CIN incidence.


Subject(s)
Papillomavirus Infections , Uterine Cervical Dysplasia , Beijing , Epidemiologic Studies , Female , Humans , Papillomavirus Infections/virology , Uterine Cervical Neoplasms/diagnosis , Uterine Cervical Dysplasia/virology
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