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1.
Materials (Basel) ; 17(17)2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39274744

RESUMEN

Aluminum nanoparticles (nAl) have received sustained interest due to their higher reactivity than micron aluminum particles (mAl). However, in practice, the densities of explosive formulations with nAl are far smaller than those with mAl, which greatly undercuts the energy release performance. To take advantages of both kinds of Al particles, in situ integration of mAl@nAl composites was proposed and evaluated. The mAl@nAl composites were prepared by in situ electrical explosion of Al wire. Their morphology, density, and specific surface area (SSA) were characterized by scanning electron microscope (SEM), densimetry, and Brunauer-Emmett-Teller (BET), respectively. SEM showed that nAl uniformly adhered to the surface of mAl. With the increase in voltage, the average diameter and density of the composites decreased, but the SSA of the composites increased. And the largest density of the composites was 1.13 g/cm3, comparable to that of the commercial graded Al product (1.25 g/cm3). Meanwhile, the highest SSA of the composites was 12.1192 m2/g. In addition, the combustion efficiency of mAl@nAl composites at 20 kV was 8.26% higher than that of physically graded counterparts. The constant-volume combustion test under zero oxygen balance revealed that the pressurization rate and peak pressure of mAl@nAl composites prepared at 20 kV were the highest of all. Furthermore, constant-volume combustion under constant heat showed that the combustion temperatures of mAl@nAl composites were 1.15-1.45 times higher than those of physically graded counterparts. Finally, the ignition delay of mAl@nAl composites was reduced with the increase in explosion voltage.

2.
Acta Neurol Belg ; 124(1): 91-99, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37525074

RESUMEN

BACKGROUND: Nemaline myopathy, the most common of the congenital myopathies, is caused by various genetic mutations. In this study, we attempted to investigate the clinical features, muscle pathology and genetic features of 15 patients with nemaline myopathy. RESULTS: Among the 15 patients, there were 9 (60.00%) males and 6 (40.00%) females, and 9 (60.00%) of them came from three families respectively. The age of seeing a doctor ranged from 9 to 52 years old, the age of onset was from 5 to 23 years old, and the duration of disease ranged from 3 to 35 years. Ten out of the 15 patients had high arched palate and elongated face. Only one patient had mild respiratory muscle involvement and none had dysphagia. Muscle biopsies were performed in 9 out of the 15 patients. Pathologically, muscle fibers of different sizes, atrophic muscle fibers and compensatory hypertrophic fibers could be found, and occasionally degenerated and necrotic muscle fibers were observed. Different degrees of nemaline bodies aggregation could be seen in all 9 patients. The distribution of type I and type II muscle fibers were significantly abnormal in patients with nemaline myopathy caused by NEB gene, however, it was basically normal in patients with nemaline myopathy caused by TPM3 gene and ACTA1 gene. Electron microscopic analysis of 6 patients showed that nemaline bodies aggregated between myofibrils were found in 5(83.33%) cases, and most of them were located near the Z band, but no intranuclear rods were found. The gene analysis of 15 NM patients showed that three NM-related genes were harbored, including 11 (73.33%) patients with NEB, 3 (20.00%) patients with TPM3, and 1 (6.67%) patient with ACTA1, respectively. A total of 12 mutation sites were identified and included 10 (83.33%) mutations in exon and 2(16.67%) mutations in intron. CONCLUSIONS: The clinical phenotype of nemaline myopathy is highly heterogeneous. Muscle pathology shows that nemaline bodies aggregation is an important feature for the diagnosis of NM. NEB is the most frequent causative gene in this cohort. The splicing mutation, c.21522 + 3A > G may be the hotspot mutation of the NEB gene in Chinese NM patients.


Asunto(s)
Enfermedades Musculares , Miopatías Nemalínicas , Masculino , Femenino , Humanos , Niño , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Miopatías Nemalínicas/genética , Miopatías Nemalínicas/patología , Músculo Esquelético/patología , Mutación , China
3.
Journal of Leukemia & Lymphoma ; (12): 161-171, 2024.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1017401

RESUMEN

Objective:To systematically evaluate the efficacy and safety of ruxolitinib in the treatment of Chinese patients with refractory graft-versus-host disease(SR-GVHD) by using meta-analysis.Methods:China National Knowledge Infrastructure(CNKI), WanFang database, VIP database, China Biology Medicine disc, PubMed, Ebscore Medline, EMBASE, Web of Science Core Collection and Cochrane Library were searched by using "ruxolitinib" "Graft vs Host Disease" "graft versus host disease" "Graft-Versus-Host Disease" as key words. The retrieve time was from the establishment of the database to December 7th, 2021. The related literatures of ruxolitinib for Chinese patients with SR-GVHD were screened according to inclusion and exclusion criteria, and the characteristics of the literatures were extracted. Outcomes indexes included overall objective response rate (ORR), proportion of hormone reduction and discontinuation, survival indexes and incidence of adverse events. Meta-analysis of ORR, remission rate of affected organs, 12-month overall survival rate, overall mortality and mortality due to graft-versus-host disease (GVHD) were performed by using Stata 16.0 software or R3.6.3 software. The statistics analysis was performed on the hormone usage and adverse events.Results:A total of 19 literatures involving 775 Chinese patients with SR-GVHD treated by ruxolitinib were included. Meta analysis showed that the ORR of ruxolitinib for treatment of acute GVHD (aGVHD) was 84% (285/339), with moderate heterogeneity among studies ( I2 = 62.04%, P<0.01), and the complete remission (CR) rate, partial remission (PR) rate and non-remission (NR) rate was 56% (190/339), 28% (95/339), and 14%(47/339), respectively. The ORR of ruxolitinib for treatment of chronic GVHD (cGVHD) was 77% (332/431), with moderate heterogeneity among studies ( I2 = 50.17%, P = 0.02), and the CR rate, PR rate and NR rate was 36% (155/431), 41% (177/431) and 21% (91/431), respectively. As for hormone usage, 46.51% of aGVHD patients had steroid reduction and 34.88% patients had steroid discontinuation. Similarly, 28.2% of patients with cGVHD had steroid reduction and 36.9% had steroid discontinuation. The overall 12-month survival rate of patients with SR-GVHD after the treatment of ruxolitinib was 71% (95% CI: 63%-79%, I2 = 72.70%, P<0.01). Adverse events occurred for 760 times in total, among which 287 times (36.0%) of viral infection and 269 times (34.7%) of hemocytopenia were the most common adverse events. Conclusions:Ruxolitinib is effective in the treatment of Chinese patients with SR-GVHD, and it helps reduce hormone-dependency and prolong the survival time.

4.
Tianjin Medical Journal ; (12): 290-296, 2024.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1021012

RESUMEN

Objective To observe and compare in-hospital and 1-year survival and prognosis of patients with 4b acute myocardial infarction(AMI)caused by early and late stent thrombosis(ST).Methods A total of 302 patients with 4b acute myocardial infarction caused by ST were enrolled in this study from January 2015 to February 2018.ST patients were confirmed by coronary angiography.These patients were divided into two groups:the early ST group(n=26)and the late ST group(n=276)according to the time of ST occurrence.Endpoint events during hospitalization and one year of follow up were compared between the two groups of patients.The primary endpoint events included cardiac death and recurrent AMI.The secondary endpoint events included target lesion revascularization(TLR),re-stent thrombosis,heart failure and stroke.The incidence of no endpoint events was compared between two groups of patients by Kaplan and Meier survival analysis.Cox regression analysis was used to analyze risk factors for endpoint events in patients with type 4b AMI.Results There was no significant difference in the incidence of the primary endpoint events during hospitalization between the two groups(7.7%vs.3.3%,P=0.243).The incidence of heart failure was higher in the early ST group than that of the late ST group(11.5%vs.1.4%,P=0.016).There was no significant difference in the incidence rates of other secondary endpoint events between the two groups(P>0.05).After a mean follow-up of 1 year,the incidence rates of primary endpoint events and the secondary eendpoint events were higher in the early ST group(20.0%vs.5.9%,P<0.05 and 36.0%vs.11.5%,P<0.01)than that of the late ST group.Kaplan and Meier survival analysis showed that the 1-year cumulative incidences of non-primary(P= 0.022)and non-secondary events(P<0.001)were lower in the early ST group than those of the late ST group.Cox regression analysis showed that hypertension and history of coronary artery bypass grafting were independent risk factors for primary endpoint events in patients with 4b AMI,and intraoperative implantation of intraaortic balloon pump(IABP)and shortening the time from stent thrombosis to balloon dilation(ST to B)were independent protective factor.Conclusion Early ST patients have similar in-hospital outcomes and poor long-term prognosis compared with late ST induced 4b type AMI patients.Intraoperative implantation of IABP and shortening of ST to B time may improve the prognosis of 4b type AMI patients.

5.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1021583

RESUMEN

BACKGROUND:Bone tissue remodeling is closely related to stress loading.Currently,there are few studies or guidelines on the relationship between bone and occlusal adjustment of implant prostheses and there is also a lack of scientific evidence. OBJECTIVE:To investigate the effects of different implant occlusal gaps on stress distribution,stress peak and displacement at the implant-bone interface under Ⅰ-Ⅳ bone conditions by a finite element method. METHODS:After scanning the equal-scale tooth model with an optical scanner,equal-scale models of the upper right first molar Straumann 4.8×8 mm BL RC implant and its related components was constructed using Solidworks 2022.Then,using Mimics,Geomagic,and Solidworks software,the maxillary and mandibular bone models of class Ⅰ-Ⅳ bones were established based on the bone classification proposed by ZARB and LEKHOLM in the literature,and the NORTON and TRISI bone density classification method.The models were assembled with the occlusal gaps of 0,20,40,60,80,and 100 μm for the restorations,and an additional set of homogeneous models without density ratio settings was constructed for comparison.After the above models were imported into Hypermesh for meshing,the material assignment,boundary constraints and parameter setting were performed for the finite element analysis.Finally,250 N was used as the loading force to simulate the maxillary and mandibular stress conditions.Stress distribution,peak stress and displacement of the implant-bone interface in each group of models were analyzed and compared. RESULTS AND CONCLUSION:Under the same loading conditions,the stresses in the implant restorations were evenly distributed with the occlusal contact points.When the occlusal gap reached 80 and 100 μm,stress interruptions occurred in the implant crowns under class Ⅰ bone and class Ⅱ,Ⅲ and Ⅳ bones,respectively.The displacement of the implant-bone interface was mainly concentrated in the cortical bone region around the implant and transmitted down the long axis of the implant to the cancellous bone region at the bottom.With the changes of class Ⅰ-Ⅳ jaw bones,the displacement and Von Mises stress in the cortical bone region increased in all groups,and were greater than those in the cancellous bone region.The Von Mises stress in the cancellous bone region was similar to that in the cortical bone region except that it showed a downward trend from class Ⅱ bone.However,when the occlusal gap increased,the stress and displacement peak values in the cortical bone and the cancellous bone showed a decreasing trend.The stress of the implant-bone interface was between 20 MPa and 60 MPa when the occlusal gap was 0-40 μm for class Ⅱ-Ⅳ bones and 60 μm for class Ⅳ bone,and the stress of the other groups was less than 20 MPa.The Von Mises stress was mainly concentrated in the neck of the implant,and the peak value of von Mises stress in class Ⅱ-Ⅳ bones with the occlusal gap of 20 μm was higher than that(144.10 MPa)in class Ⅰ bone with the occlusal gap of 0 μm.In the homogeneous model with different elastic moduli,the distribution of stress and displacement was more uniform than that in the heterogeneous model and the occlusal space should increase with the decrease of jaw bone density in clinical practice.To conclude,from the perspective of biomechanics,the alveolar bone should be taken into account in the occlusal adjustment of implant denture.An occlusal gap of 20-40 μm between a single dental implant and a natural tooth in the opposite jaw is a relatively suitable solution for occlusal adjustment under different bone conditions.However,due to the particularity of finite element analysis method,it needs to be further studied in combination with clinical practice.

6.
Modern Hospital ; (6): 7-10, 2024.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1022187

RESUMEN

Objective To explore the research status,hot topics and trends in the construction of integrity in public hos-pitals in China,provide references for the research on integrity construction in public hospitals and promote their high-quality de-velopment.Methods The relevant literature on the construction of integrity in public hospitals from 2009 to 2022 was collected from the China National Knowledge Infrastructure(CNKI)database.CiteSpace software was used to analyze the selected litera-ture in terms of publication timeline,author co-citation,institution co-citation,keyword co-occurrence,keyword clustering and keyword burst analysis,and visualize the knowledge graph.Results The research on the construction of integrity in public hos-pitals in China showed an upward trend from 2009 to 2022.The hot topics in the research mainly focused on incorruptible medical practices,integrity risks and integrity culture.The keyword burst analysis revealed that discipline inspection and supervision,in-formation platforms and institutional development were the future research directions.Conclusion The research on the construc-tion of integrity in public hospitals in China has a clear policy orientation,and various subfields are being explored.Internal inde-pendent research is predominant,while collaboration among multiple scholars and institutions needs to be strengthened.The con-struction of integrity in public hospitals in China mainly focuses on three areas.

7.
International Eye Science ; (12): 484-490, 2024.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1011406

RESUMEN

AIM: To evaluate the clinical effect of toric implantable collamer lens(TICL)V4c for correcting moderate to high myopia with high astigmatism using vector analysis and quality of life impact of refractive correction(QIRC).METHODS: Retrospective case series. A total of 55 patients(90 eyes)with moderate to high myopia and high astigmatism who received TICL V4c implantation in the refraction surgery center of ophthalmology department in our hospital from January 2019 to December 2022 were collected. Followed-up for 1 a, the uncorrected distance visual acuity(UDVA), best corrected visual acuity(BCVA)and diopters were observed. Alpins vector analysis was used to evaluate the effect of astigmatism correction, and QIRC scale was used to evaluate patients' quality of life.RESULTS: At 1 a postoperatively, the UDVA of 98% eyes was the same or better than pre-operative BCVA, the safety index was 1.11±0.14, and the efficacy index was 1.11±0.15. The angle of error of 97% of the astigmatic eyes was within ±15°. The results of vector analysis showed that correction index was 0.83±0.13, angle of error was 1.00±4.49°, and index of success was 0.21±0.15. The total higher order aberrations under a pupil diameter of 6 mm was significantly increased compared with preoperatively(P&#x003C;0.05), the QIRC score was significantly better than that before surgery(P&#x003C;0.001), and the increase of total QIRC scores was positively correlated with preoperative spherical equivalent(rs=0.215, P&#x003C;0.05), indicating that the higher degree of myopia before surgery the patients, the better the quality of life after TICL implantation.CONCLUSION: TICL V4c implantation for the correction of moderate to high myopia with high astigmatism is safe and effective, and the patients' quality of life significantly improved after surgery.

8.
Chinese Medical Journal ; (24): 922-932, 2023.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-980843

RESUMEN

BACKGROUND@#Pancreatic β-cells elevate insulin production and secretion through a compensatory mechanism to override insulin resistance under metabolic stress conditions. Deficits in β-cell compensatory capacity result in hyperglycemia and type 2 diabetes (T2D). However, the mechanism in the regulation of β-cell compensative capacity remains elusive. Nuclear factor-Y (NF-Y) is critical for pancreatic islets' homeostasis under physiological conditions, but its role in β-cell compensatory response to insulin resistance in obesity is unclear.@*METHODS@#In this study, using obese ( ob/ob ) mice with an absence of NF-Y subunit A (NF-YA) in β-cells ( ob , Nf-ya βKO) as well as rat insulinoma cell line (INS1)-based models, we determined whether NF-Y-mediated apoptosis makes an essential contribution to β-cell compensation upon metabolic stress.@*RESULTS@#Obese animals had markedly augmented NF-Y expression in pancreatic islets. Deletion of β-cell Nf-ya in obese mice worsened glucose intolerance and resulted in β-cell dysfunction, which was attributable to augmented β-cell apoptosis and reactive oxygen species (ROS). Furthermore, primary pancreatic islets from Nf-ya βKO mice were sensitive to palmitate-induced β-cell apoptosis due to mitochondrial impairment and the attenuated antioxidant response, which resulted in the aggravation of phosphorylated c-Jun N-terminal kinase (JNK) and cleaved caspase-3. These detrimental effects were completely relieved by ROS scavenger. Ultimately, forced overexpression of NF-Y in INS1 β-cell line could rescue palmitate-induced β-cell apoptosis, dysfunction, and mitochondrial impairment.@*CONCLUSION@#Pancreatic NF-Y might be an essential regulator of β-cell compensation under metabolic stress.


Asunto(s)
Ratas , Ratones , Animales , Especies Reactivas de Oxígeno/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Resistencia a la Insulina , Insulina , Células Secretoras de Insulina/metabolismo , Apoptosis , Estrés Fisiológico , Factores de Transcripción/metabolismo , Palmitatos/farmacología , Obesidad/metabolismo
9.
Chinese Journal of Geriatrics ; (12): 303-309, 2023.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-993812

RESUMEN

Objective:To compare the effects of staged percutaneous coronary intervention(PCI)after emergency PCI and emergency culprit-only PCI on clinical outcomes of elderly patients with ST-segment elevation myocardial infarction(STEMI)and multivessel disease.Methods:A retrospective analysis was performed on 389 elderly patients with STEMI and multivessel lesions, aged ≥70 years and within 12 h of onset, admitted to the Clinical College of Thoracic Medicine, Tianjin Medical University, between January 2014 and September 2019.According to different revascularization strategies, enrolled patients were divided into the culprit-only PCI group(79.18%, 308)and the staged PCI group(20.82%, 81). Kaplan-Meier analysis and the Cox proportional hazards regression model were used to compare the incidences of major adverse cardiac and cerebrovascular events(MACCE), all-cause death, cardiac death, recurrent myocardial infarction, stroke and ischemia-driven revascularization between the two groups and to evaluate the effects of different revascularization strategies on MACCE and all-cause death.Then subgroup analysis was performed.Results:During a 56-month follow-up, 131 patients developed MACCE and 96 patients died.Compared with the culprit-only PCI group, the staged PCI group had a lower risk of MACCE( HR: 0.404, 95% CI: 0.227-0.716, P=0.002), all-cause death( HR: 0.354, 95% CI: 0.171-0.730, P=0.005), cardiac death( HR: 0.363, 95% CI: 0.157-0.838, P=0.018), and recurrent myocardial infarction( HR: 0.229, 95% CI: 0.055-0.953, P=0.043). There was no significant difference in the incidence of stroke or ischemia-driven revascularization between the two groups( P>0.05). The reduced risk with staged PCI for MACCE and for all-cause mortality persisted in all subgroups.Multivariate Cox proportional hazards regression revealed that, after adjusting for confounding factors, staged PCI was an independent protective factor for MACCE( HR: 0.44, 95% CI: 0.239-0.815, P=0.009)and for all-cause death( HR: 0.390, 95% CI: 0.90, P=0.020). Conclusion:Compared with culprit-only PCI, staged PCI can significantly improve the long-term prognosis of elderly patients ≥70 years with STEMI and multivessel disease within 12 h of onset.

10.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1031821

RESUMEN

@#Persistent postural-perceptual dizziness (PPPD) is a common clinical chronic dizziness disease,with persistent dizziness,instability,or non-rotational vertigo as the main symptom. It may be aggravated by postural changes,active/passive movements,and exposure to complex visual environments. At present,it is believed that the occurrence of PPPD may be related to the failure of postural control readaptation and abnormal cortical multisensory integration,but the specific pathophysiological mechanism is not clear. In recent years,with the continuous application of neuroimaging technology in the field of vertigo diseases,it has been found that in patients with PPPD,the brain structure,function,and connectivity related to vestibular multisensory and spatial orientation are decreased,while the function and connectivity related to visual processing are enhanced. At the same time,various psychiatric factors (such as anxiety,depression,and neuroticism) as well as triggers may be involved in regulating the brain structure of people with PPPD,which helps explain the differences in outcomes between studies. The above neuroimaging findings are helpful for the early diagnosis and treatment of PPPD. Therefore,this paper reviews the neuroimaging studies of PPPD to provide a reference for explaining the pathophysiological mechanism of PPPD.

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