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1.
Nature ; 578(7796): 559-562, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32103194

RESUMEN

Strain-hardening (the increase of flow stress with plastic strain) is the most important phenomenon in the mechanical behaviour of engineering alloys because it ensures that flow is delocalized, enhances tensile ductility and inhibits catastrophic mechanical failure1,2. Metallic glasses (MGs) lack the crystallinity of conventional engineering alloys, and some of their properties-such as higher yield stress and elastic strain limit3-are greatly improved relative to their crystalline counterparts. MGs can have high fracture toughness and have the highest known 'damage tolerance' (defined as the product of yield stress and fracture toughness)4 among all structural materials. However, the use of MGs in structural applications is largely limited by the fact that they show strain-softening instead of strain-hardening; this leads to extreme localization of plastic flow in shear bands, and is associated with early catastrophic failure in tension. Although rejuvenation of an MG (raising its energy to values that are typical of glass formation at a higher cooling rate) lowers its yield stress, which might enable strain-hardening5, it is unclear whether sufficient rejuvenation can be achieved in bulk samples while retaining their glassy structure. Here we show that plastic deformation under triaxial compression at room temperature can rejuvenate bulk MG samples sufficiently to enable strain-hardening through a mechanism that has not been previously observed in the metallic state. This transformed behaviour suppresses shear-banding in bulk samples in normal uniaxial (tensile or compressive) tests, prevents catastrophic failure and leads to higher ultimate flow stress. The rejuvenated MGs are stable at room temperature and show exceptionally efficient strain-hardening, greatly increasing their potential use in structural applications.

2.
Mol Psychiatry ; 29(2): 369-386, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38102482

RESUMEN

Understanding the role of small, soluble aggregates of beta-amyloid (Aß) and tau in Alzheimer's disease (AD) is of great importance for the rational design of preventative therapies. Here we report a set of methods for the detection, quantification, and characterisation of soluble aggregates in conditioned media of cerebral organoids derived from human iPSCs with trisomy 21, thus containing an extra copy of the amyloid precursor protein (APP) gene. We detected soluble beta-amyloid (Aß) and tau aggregates secreted by cerebral organoids from both control and the isogenic trisomy 21 (T21) genotype. We developed a novel method to normalise measurements to the number of live neurons within organoid-conditioned media based on glucose consumption. Thus normalised, T21 organoids produced 2.5-fold more Aß aggregates with a higher proportion of larger (300-2000 nm2) and more fibrillary-shaped aggregates than controls, along with 1.3-fold more soluble phosphorylated tau (pTau) aggregates, increased inflammasome ASC-specks, and a higher level of oxidative stress inducing thioredoxin-interacting protein (TXNIP). Importantly, all this was detectable prior to the appearance of histological amyloid plaques or intraneuronal tau-pathology in organoid slices, demonstrating the feasibility to model the initial pathogenic mechanisms for AD in-vitro using cells from live genetically pre-disposed donors before the onset of clinical disease. Then, using different iPSC clones generated from the same donor at different times in two independent experiments, we tested the reproducibility of findings in organoids. While there were differences in rates of disease progression between the experiments, the disease mechanisms were conserved. Overall, our results show that it is possible to non-invasively follow the development of pathology in organoid models of AD over time, by monitoring changes in the aggregates and proteins in the conditioned media, and open possibilities to study the time-course of the key pathogenic processes taking place.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Síndrome de Down , Células Madre Pluripotentes Inducidas , Organoides , Proteínas tau , Humanos , Organoides/metabolismo , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/genética , Proteínas tau/metabolismo , Síndrome de Down/metabolismo , Síndrome de Down/genética , Síndrome de Down/patología , Células Madre Pluripotentes Inducidas/metabolismo , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Neuronas/metabolismo , Encéfalo/metabolismo , Encéfalo/patología , Proteínas Portadoras/metabolismo , Proteínas Portadoras/genética , Trisomía/genética , Estrés Oxidativo , Placa Amiloide/metabolismo , Placa Amiloide/patología , Medios de Cultivo Condicionados , Microscopía Fluorescente/métodos
3.
Phys Rev Lett ; 132(9): 099901, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38489658

RESUMEN

This corrects the article DOI: 10.1103/PhysRevLett.123.107703.

4.
Bull Exp Biol Med ; 176(4): 515-518, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38492109

RESUMEN

We studied the effect of structural properties of deproteinized spongy bone (DSB) on functional activity of adipose tissue mesenchymal stromal cells of (MSC) for the potential use of these materials as components of a combined tissue-engineered construct. The porosity of the structure of DSB samples and the pore size promote MSC adhesion, migration, and proliferation on their surface and in the depth, revealing the architectonics of this bone matrix. The depth of cell penetration into the samples (from 273 to 702 µm) and an increase in the total number of cells (from 302 on day 1 to 1744 on day 7) demonstrated MSC adhesion, migration, and proliferation. The viability of cultured MSC was preserved for up to 7 days. The obtained results prove the possibility of using allogeneic DSB from femoral heads as a bone matrix in tissue-engineered constructs in combination with MSC. Such constructs can be used to efficiently restore the structural and functional integrity of the bone tissue in abnormal processes of various etiopathogenesis associated with the formation of bone defects or bone tissue deficiency.


Asunto(s)
Hueso Esponjoso , Células Madre Mesenquimatosas , Ingeniería de Tejidos/métodos , Matriz Ósea , Tejido Adiposo , Células Cultivadas , Diferenciación Celular
5.
Dokl Biochem Biophys ; 516(1): 53-57, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38700816

RESUMEN

Study of CD4+ T cell response and T cell receptor (TCR) specificity is crucial for understanding etiology of immune-mediated diseases and developing targeted therapies. However, solubility, accessibility, and stability of synthetic antigenic peptides used in T cell assays may be a critical point in such studies. Here we present a T cell activation reporter system using recombinant proteins containing antigenic epitopes fused with bacterial thioredoxin (trx-peptides) and obtained by bacterial expression. We report that co-incubation of CD4+ HA1.7 TCR+ reporter Jurkat 76 TRP cells with CD80+ HLA-DRB1*01:01+ HeLa cells or CD4+ Ob.1A12 TCR+ Jurkat 76 TRP with CD80+ HLA-DRB1*15:01+ HeLa cells resulted in activation of reporter Jurkat 76 TPR after addition of recombinant trx-peptide fusion proteins, containing TCR-specific epitopes. Trx-peptides were comparable with corresponding synthetic peptides in their capacity to activate Jurkat 76 TPR. These data demonstrate that thioredoxin as a carrier protein (trx) for antigenic peptides exhibits minimal interference with recognition of MHC-specific peptides by TCRs and consequent T cell activation. Our findings highlight potential feasibility of trx-peptides as a reagent for assessing the immunogenicity of antigenic fragments.


Asunto(s)
Linfocitos T CD4-Positivos , Péptidos , Receptores de Antígenos de Linfocitos T , Proteínas Recombinantes de Fusión , Tiorredoxinas , Humanos , Tiorredoxinas/inmunología , Tiorredoxinas/genética , Células Jurkat , Linfocitos T CD4-Positivos/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo , Proteínas Recombinantes de Fusión/farmacología , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/inmunología , Péptidos/farmacología , Péptidos/inmunología , Péptidos/química , Activación de Linfocitos/efectos de los fármacos , Células HeLa
6.
Zhonghua Wai Ke Za Zhi ; 62(8): 744-750, 2024 Jun 28.
Artículo en Zh | MEDLINE | ID: mdl-38937125

RESUMEN

Objective: To evaluate the long-term outcomes and prognostic factors of locally advanced gastric cancer with serosa-invasion. Methods: This study is a retrospective cohort study. The clinical and pathological data of 495 patients with locally advanced gastric cancer with serosa-invasion who underwent laparoscopic radical gastrectomy in Department of General Surgery, the First Hospital Affiliated to Army Medical University from October 2012 to October 2018 was analyzed retrospectively. There were 356 males and 139 females with an age (M(IQR)) of 59 (16) years (range: 18 to 75 years). Observation indicators included postoperative results and long-term prognosis. The survival curve was drawn by the Kaplan-Meier method. Univariate and multivariate prognostic analysis was performed using the Cox proportional hazards model. Results: Among the 495 patients, a total of 57 patients (11.5%) were lost to follow-up, with a follow-up time of 89 (40) months (range: 23 to 134 months). The 5-year disease-free survival rate (DFS) and the 5-year overall survival rate (OS) were 56.0% and 58.2%, respectively. The 5-year DFS for patients with stage ⅡB, ⅢA, ⅢB, ⅢC were 71.2%, 60.5%, 51.6%, 33.3%, respectively. The 5-year OS for patients with stage ⅡB, ⅢA, ⅢB, ⅢC were 71.2%, 62.2%, 54.1%, 39.3%, respectively. Multivariate analysis showed that age >65 years (DFS: HR=1.402, 95%CI: 1.022 to 1.922, P=0.036; OS: HR=1.461, 95%CI: 1.057 to 2.019, P=0.022), lymph node dissection number less than 25 (DFS: HR=1.348, 95%CI: 1.019 to 1.779, P=0.036; OS: HR=1.376, 95%CI: 1.035 to 1.825, P=0.028), pathological stage Ⅲ (DFS: HR=2.131, 95%CI: 1.444 to 3.144, P<0.01; OS: HR=2.079, 95%CI: 1.406 to 3.074, P<0.01), and no postoperative chemotherapy (DFS: HR=3.127, 95%CI: 2.377 to 4.113, P<0.01; OS: HR=3.768, 95%CI: 2.828 to 5.020, P<0.01) were independent prognostic factors for the decrease in DFS and OS rates. Conclusions: Laparoscopic radical gastrectomy for locally advanced gastric cancer with serosa-invasion could achieve satisfactory long-term oncological outcomes. More lymph node dissection and standardized postoperative adjuvant chemotherapy are expected to further improve the prognosis of patients with locally advanced gastric cancer with serous invasion after laparoscopic radical surgery.

7.
Sud Med Ekspert ; 67(2): 39-42, 2024.
Artículo en Ruso | MEDLINE | ID: mdl-38587157

RESUMEN

A rare clinical observation of death from prolonged uneven external irradiation due to the deliberate use of an ionizing radiation source for illegal purposes has been presented. The main difficulties of postmortem diagnosis of this type of radiation-induced injury, considering the features of histological examinations and special methods of retrospective dosimetric evaluations, have been identified.


Asunto(s)
Radiación Ionizante , Estudios Retrospectivos
8.
Sud Med Ekspert ; 67(2): 20-27, 2024.
Artículo en Ruso | MEDLINE | ID: mdl-38587154

RESUMEN

OBJECTIVE: To study emergence mechanism, physical nature, pattern of intravital and postmortem changes of biological and non-biological objects originated in the period from 1550 to 1918 yr. using traditional X-ray and X-ray computed tomography. MATERIAL AND METHODS: The relics of Saint Macarius the Roman of Novgorod, the remains of the First Reverend of the Resurrection Novodevichy Convent in Saint Petersburg Mother Superior Theophania, damages on the chair leg on which Tsesarevich Alexey sat during the shooting of Russian Emperor Nicholas II, his family and entourage in 1918 in Yekaterinburg were stidued. RESULTS AND CONCLUSION: The application of highly informative methods of traditional X-ray and X-ray computed tomography of biological and non-biological objects showed their high informativity and allowed to correctly interpret the emergence mechanism, physical nature, pattern of intravital and postmortem changes of skeleton bones and historical artefact (chair legs) originated long ago. The necessity of special professional training and advanced training of experts in forensic radiology to prevent possible diagnostic and expert errors has been substantiated.


Asunto(s)
Artefactos , Cambios Post Mortem , Humanos , Rayos X , Tomografía Computarizada por Rayos X/métodos
9.
Anal Chem ; 95(41): 15254-15263, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37782556

RESUMEN

The formation of soluble α-synuclein (α-syn) and amyloid-ß (Aß) aggregates is associated with the development of Parkinson's disease (PD). Current methods mainly focus on the measurement of the aggregate concentration and are unable to determine their heterogeneous size and shape, which potentially also change during the development of PD due to increased protein aggregation. In this work, we introduce aptamer-assisted single-molecule pull-down (APSiMPull) combined with super-resolution fluorescence imaging of α-syn and Aß aggregates in human serum from early PD patients and age-matched controls. Our diffraction-limited imaging results indicate that the proportion of α-syn aggregates (α-syn/(α-syn+Aß)) can be used to distinguish PD and control groups with an area under the curve (AUC) of 0.85. Further, super resolution fluorescence imaging reveals that PD serums have a higher portion of larger and rounder α-syn aggregates than controls. Little difference was observed for Aß aggregates. Combining these two metrics, we constructed a new biomarker and achieved an AUC of 0.90. The combination of the aggregate number and morphology provides a new approach to early PD diagnosis.


Asunto(s)
Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/metabolismo , Agregado de Proteínas , alfa-Sinucleína/metabolismo , Péptidos beta-Amiloides/metabolismo
10.
Phys Rev Lett ; 130(14): 146101, 2023 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-37084444

RESUMEN

Because of the half-filled t_{2g}-electron configuration, the BO_{6} octahedral distortion in a 3d^{3} perovskite system is usually very limited. In this Letter, a perovskitelike oxide Hg_{0.75}Pb_{0.25}MnO_{3} (HPMO) with a 3d^{3} Mn^{4+} state was synthesized by using high pressure and high temperature methods. This compound exhibits an unusually large octahedral distortion enhanced by approximately 2 orders of magnitude compared with that observed in other 3d^{3} perovskite systems like RCr^{3+}O_{3} (R=rare earth). Essentially different from centrosymmetric HgMnO_{3} and PbMnO_{3}, the A-site doped HPMO presents a polar crystal structure with the space group Ama2 and a substantial spontaneous electric polarization (26.5 µC/cm^{2} in theory) arising from the off-center displacements of A- and B-site ions. More interestingly, a prominent net photocurrent and switchable photovoltaic effect with a sustainable photoresponse were observed in the current polycrystalline HPMO. This Letter provides an exceptional d^{3} material system which shows unusually large octahedral distortion and displacement-type ferroelectricity violating the "d^{0}-ness" rule.

11.
Brain ; 145(2): 632-643, 2022 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-34410317

RESUMEN

Aggregation of α-synuclein plays a key role in the development of Parkinson's disease. Soluble aggregates are present not only within human brain but also the CSF and blood. Characterizing the aggregates present in these biofluids may provide insights into disease mechanisms and also have potential for aiding diagnosis. We used two optical single-molecule imaging methods called aptamer DNA-PAINT and single-aggregate confocal fluorescence, together with high-resolution atomic force microscopy for specific detection and characterization of individual aggregates with intermolecular ß-sheet structure, present in the CSF and serum of 15 early stage Parkinson's disease patients compared to 10 healthy age-matched controls. We found aggregates ranging in size from 20 nm to 200 nm, in both CSF and serum. There was a difference in aggregate size distribution between Parkinson's disease and control groups with a significantly increased number of larger aggregates (longer than 150 nm) in the serum of patients with Parkinson's disease. To determine the chemical composition of the aggregates, we performed aptamer DNA-PAINT on serum following α-synuclein and amyloid-ß immunodepletion in an independent cohort of 11 patients with early stage Parkinson's disease and 10 control subjects. ß-Sheet aggregates in the serum of Parkinson's disease patients were found to consist of, on average, 50% α-synuclein and 50% amyloid-ß in contrast to 30% α-synuclein and 70% amyloid-ß in control serum [the differences in the proportion of these aggregates were statistically significant between diseased and control groups (P = 1.7 × 10-5 for each species)]. The ratio of the number of ß-sheet α-synuclein aggregates to ß-sheet amyloid-ß aggregates in serum extracted using our super-resolution method discriminated Parkinson's disease cases from controls with an accuracy of 98.2% (AUC = 98.2%, P = 4.3 × 10-5). Our data suggest that studying the protein aggregates present in serum can provide information about the disruption of protein homeostasis occurring in Parkinson's disease and warrants further investigation as a potential biomarker of disease.


Asunto(s)
Enfermedad de Parkinson , alfa-Sinucleína , Péptidos beta-Amiloides/metabolismo , Biomarcadores/metabolismo , Encéfalo/metabolismo , Humanos , Enfermedad de Parkinson/metabolismo , Agregado de Proteínas , alfa-Sinucleína/metabolismo
12.
Nature ; 541(7636): 242-246, 2017 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-27841871

RESUMEN

Riboswitches are structural RNA elements that are generally located in the 5' untranslated region of messenger RNA. During regulation of gene expression, ligand binding to the aptamer domain of a riboswitch triggers a signal to the downstream expression platform. A complete understanding of the structural basis of this mechanism requires the ability to study structural changes over time. Here we use femtosecond X-ray free electron laser (XFEL) pulses to obtain structural measurements from crystals so small that diffusion of a ligand can be timed to initiate a reaction before diffraction. We demonstrate this approach by determining four structures of the adenine riboswitch aptamer domain during the course of a reaction, involving two unbound apo structures, one ligand-bound intermediate, and the final ligand-bound conformation. These structures support a reaction mechanism model with at least four states and illustrate the structural basis of signal transmission. The three-way junction and the P1 switch helix of the two apo conformers are notably different from those in the ligand-bound conformation. Our time-resolved crystallographic measurements with a 10-second delay captured the structure of an intermediate with changes in the binding pocket that accommodate the ligand. With at least a 10-minute delay, the RNA molecules were fully converted to the ligand-bound state, in which the substantial conformational changes resulted in conversion of the space group. Such notable changes in crystallo highlight the important opportunities that micro- and nanocrystals may offer in these and similar time-resolved diffraction studies. Together, these results demonstrate the potential of 'mix-and-inject' time-resolved serial crystallography to study biochemically important interactions between biomacromolecules and ligands, including those that involve large conformational changes.


Asunto(s)
Cristalografía por Rayos X/métodos , Nanotecnología/métodos , Conformación de Ácido Nucleico , ARN Bacteriano/química , Riboswitch , Regiones no Traducidas 5'/genética , Aptámeros de Nucleótidos/química , Cristalización , Difusión , Electrones , Cinética , Rayos Láser , Ligandos , Modelos Moleculares , Pliegue del ARN , ARN Bacteriano/genética , Factores de Tiempo , Vibrio vulnificus/genética
13.
J Endocrinol Invest ; 46(2): 271-283, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35972686

RESUMEN

BACKGROUND: Stroke is one of the leading causes of disability and mortality in patients with type 2 diabetes mellitus (T2DM). Risk models have been developed for predicting stroke and stroke-associated mortality among patients with T2DM. Here, we evaluated risk factors of stroke for individualized prevention measures in patients with T2DM in northern China. METHODS: In the community-based Tianjin Chronic Disease Cohort study, 58,042 patients were enrolled between January 2014 and December 2019. We used multiple imputation (MI) to impute missing variables and univariate and multivariate Cox's proportional hazard regression to screen risk factors of stroke. Furthermore, we established and validated first-ever prediction models for stroke (Model 1 and Model 2) and death from stroke (Model 3) and evaluated their performance. RESULTS: In the derivation and validation groups, the area under the curves (AUCs) of Models 1-3 was better at 5 years than at 8 years. The Harrell's C-index for all models was above 0.7. All models had good calibration, discrimination, and clinical net benefit. Sensitivity analysis using the MI dataset indicated that all models had good and stable prediction performance. CONCLUSION: In this study, we developed and validated first-ever risk prediction models for stroke and death from stroke in patients with T2DM, with good discrimination and calibration observed in all models. Based on lifestyle, demographic characteristics, and laboratory examination, these models could provide multidimensional management and individualized risk assessment. However, the models developed here may only be applicable to Han Chinese.


Asunto(s)
Diabetes Mellitus Tipo 2 , Accidente Cerebrovascular , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/diagnóstico , Estudios de Cohortes , Factores de Riesgo , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , China/epidemiología
14.
Zhonghua Yi Xue Za Zhi ; 103(16): 1217-1224, 2023 Apr 25.
Artículo en Zh | MEDLINE | ID: mdl-37087405

RESUMEN

Objective: To investigate the clinical value and efficacy of the nomogram model in evaluating the prognosis of cholangiocarcinoma after interventional therapy. Methods: The clinical data of 259 patients with cholangiocarcinoma who received interventional therapy at the First Affiliated Hospital of zhengzhou University from January 2014 to June 2021 were retrospectively analyzed, including 148 males and 111 females, aged from 26 to 91 (65±12) years. They were randomly divided into a training group (181 cases) and a validation group (78 cases) in a ratio of 7∶3. Cox regression analysis was performed in the training group, independent risk factors affecting the prognosis of patients were screened, and a nomogram for 6-month, 1-year, and 2-year survival was constructed. The performance of the nomogram was analyzed by calculating the area under the receiver operating characteristic curve (AUC) value, calibration curve, and decision curve, and the predictive efficacy of the model was evaluated in the validation group. Results: There was no significant difference in baseline data between the training group and the validation group, which was comparable. Regression analysis showed that T stage (T2: HR=0.147,95%CI: 0.077-0.281;T3: HR=0.207,95%CI: 0.122-0.351;T4: HR=0.864,95%CI: 0.537-1.393), tumor diameter (17-33 mm: HR=0.201,95%CI: 0.119-0.341;≥33 mm: HR=0.795,95%CI: 0.521-1.211) and differentiation degree(middle differentiation: HR=3.318,95%CI: 2.082-5.289;highly differentiation: HR=1.842,95%CI: 1.184-2.867) were risk factors affecting the prognosis of interventional therapy for cholangiocarcinoma. The AUC values of the survival curve prediction models were generally consistent between the training and validation groups, and the AUC values of the training group at 6 months, 1 year, and 2 years were 0.925 (95%CI: 0.888-0.963), 0.921 (95%CI: 0.877-0.964) and 0.974 (95%CI: 0.957-0.993), respectively. In the validation group, the 6-month, 1-year, and 2-year AUC values were 0.951 (95%CI: 0.911-0.991), 0.917 (95%CI: 0.857-0.977) and 0.848 (95%CI: 0.737-0.959), respectively, and the AUC values were all greater than 0.8, suggesting that the nomogram had better discrimination ability. The calibration curves of the prediction models of the two groups were basically consistent, and the shape of the calibration curves at 6 months and 1 year fitted the ideal curve, while the fitting degree of the calibration curves at 2 years was relatively poor. The decision curve showed the high clinical utility of this nomogram in predicting the 6-month, 1-year survival of patients with cholangiocarcinoma. Conclusions: T stage, tumor diameter, and differentiation are independent risk factors affecting the prognosis of patients with interventional cholangiocarcinoma, and the nomogram model proposed in this study has good distinguishing ability and exact clinical value for prognosis evaluation.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Femenino , Masculino , Humanos , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Nomogramas , Estudios Retrospectivos , Pronóstico , Colangiocarcinoma/terapia , Neoplasias de los Conductos Biliares/terapia , Conductos Biliares Intrahepáticos
15.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(11): 1901-1907, 2023 Nov 06.
Artículo en Zh | MEDLINE | ID: mdl-38008584

RESUMEN

High density lipoprotein (HDL) is an important biochemical index of clinical cardiovascular disease. Many new studies have demonstrated abnormalities of plasma HDL subfractions in patients with this disease,and their clinical significance is greater than the overall abnormalities of HDL. Therefore,the HDL subfraction as an important factor in cardiovascular disease has attracted extensive research and attention. This article summarizes current research on HDL subfractions,their measurements and their relationships with atherosclerosis and coronary artery disease.


Asunto(s)
Enfermedades Cardiovasculares , Enfermedad de la Arteria Coronaria , Humanos , Relevancia Clínica , HDL-Colesterol , Lipoproteínas HDL
16.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(9): 1434-1439, 2023 Sep 06.
Artículo en Zh | MEDLINE | ID: mdl-37743305

RESUMEN

Objective: To analyze the genetic characteristics of the first human infection with the G4 genotype of Eurasian avian H1N1 swine influenza virus (EA H1N1 SIV) in Shaanxi Province. Methods: The patient's throat swab samples were collected, and MDCK cells were inoculated for virus isolation to obtain the virus strain. The whole genome deep sequencing method was used to obtain the eight gene segments of the isolated strain. The nucleotide homology analysis was conducted through the Blast program in the GenBank database, and a phylogenetic tree was constructed to analyze the genetic characteristics of the virus. Results: The throat swab specimens of the case were confirmed as EA H1N1 SIV in the laboratory, and the isolated strain was named A/Shaanxi-Weicheng/1351/2022(H1N1v). Homology analysis found that the PB2, NP, HA, NA, and M genes of this isolate had the highest nucleotide homology with A/swing/Beijing/0301/2018 (H1N1), about 98.29%, 98.73%, 97.41%, 97.52%, and 99.08%, respectively. The phylogenetic tree showed that the isolate belonged to G4 genotype EA H1N1 SIV, with PB2, PB1, PA, NP and M genes from pdm/09 H1N1, HA and NA genes from EA H1N1, and NS gene from Triple-reassortant H1N1. The cleavage site of the HA protein was IPSIQSR↓G, which was the molecular characteristic of the low pathogenic influenza virus. No amino acid mutations associated with neuraminidase inhibitors were found in the NA protein. PB2 protein 701N mutation, PA protein P224S mutation, NP protein Q357K mutation, M protein P41A mutation, and NS protein 92D all indicated its enhanced adaptability to mammals. Conclusion: The patient is the first human infection with G4 genotype EA H1N1 SIV in Shaanxi province. The virus is low pathogenic, but its adaptability to mammals is enhanced. Therefore, it is necessary to strengthen the monitoring of such SIVs.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Virus de la Influenza A , Porcinos , Humanos , Animales , Subtipo H1N1 del Virus de la Influenza A/genética , Filogenia , Genotipo , China , Aves , Mamíferos
17.
Bull Exp Biol Med ; 174(4): 571-577, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36894818

RESUMEN

We studied the effect of intranasal administration of neural stem cell (NSC)-derived exosomes on behavior and cognitive functions of mice in the late period after head irradiation in a dose of 8 Gy. The used exosomes had specific markers (CD9+/CD63+, 99.5%; TSG101+, 98.4%) and mean size 105.7±8.8 nm according to dynamic light scattering data and 119.0±12.4 nm according to nanoparticle tracking analysis (NTA). Exosome suspension (2×1012 particles/ml according to NTA measurements) was administered intranasally for 4 weeks starting from 48 h after irradiation in a volume of 5 µl/nostril (2×1010 exosomes/mouse). It was shown that intranasal administration of mouse NSC-derived exosomes prevented delayed radiation-induced behavioral changes and recognition memory impairments in mice after head irradiation.


Asunto(s)
Disfunción Cognitiva , Exosomas , Células-Madre Neurales , Ratones , Animales , Disfunción Cognitiva/etiología , Disfunción Cognitiva/prevención & control
18.
Dokl Biochem Biophys ; 513(Suppl 1): S18-S22, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38189884

RESUMEN

PHF10 is a subunit of the PBAF complex, which regulates the expression of many genes in developing and maturing organisms. PHF10 has four isoforms that differ in domain structure. The PHF10A isoform, containing a DPF domain at the C-terminus and 46 amino acids at the N-terminus, is necessary for the expression of proliferation genes; the functions of the other isoforms are less studied. In this work, we have established that, upon contact inhibition of mouse and human cell proliferation caused by the establishment of a tight junction and adherence junction between cells, the expression of the PHF10A isoform stops and instead the PHF10D isoform is expressed, which does not contain DPF-domain and N-terminal sequence. The function of the PHF10D isoform may be associated with the establishment of intercellular contacts.


Asunto(s)
Ensamble y Desensamble de Cromatina , Inhibición de Contacto , Humanos , Proteínas Cromosómicas no Histona/metabolismo , Factores de Transcripción/metabolismo , Línea Celular , Isoformas de Proteínas/metabolismo , Proliferación Celular , Proteínas de Neoplasias , Proteínas de Homeodominio/metabolismo
19.
Zhonghua Yan Ke Za Zhi ; 59(12): 1003-1011, 2023 Dec 11.
Artículo en Zh | MEDLINE | ID: mdl-38061901

RESUMEN

Objective: To analyze the relationships between preoperative ocular parameters and postoperative anomalous vaults, and research their predictive diagnostic value. Methods: In this retrospective case series study, 664 eyes from 332 patients underwent posterior chamber phakic intraocular lens (pIOL) implantation at Shanghai Bright Eye Hospital and Wuxi Huaxia Eye Hospital from November 2020 to November 2021. Preoperative ocular parameters, including spherical equivalent, intraocular pressure, horizontal/vertical ciliary sulcus diameters (HCS/VCS), white-to-white diameters (WTW), corneal steep/flat curvature, central corneal thickness, anterior chamber depth (ACD), lens thickness (LT), and axial length were collected. The pIOL vaults were measured 3 months after surgery. Patients were categorized into low vault group, optimal vault group, and high vault group based on whether the vault fell within the ideal range (250 to 750 µm). Using the optimal vault group as a benchmark, receiver operating characteristic (ROC) curves were drawn for each ocular parameter of the low and high vault groups to analyze diagnostic efficiency and cut-off values for abnormal vaults after pIOL operation. Each ocular parameter was used as an independent variable to establish a multivariate logistic regression model for two different vault anomalies. ROC curves were drawn and analyzed again based on the regression results. Results: Statistically significant differences were observed in WTW, HCS-WTW, ACD, and LT among the three groups. Comparisons between each pair of groups indicated that WTW in the high vault group significantly differed from the other two groups (P<0.05), HCS-WTW in the low vault group significantly differed from the other groups (P<0.05), and ACD and LT explained statistical differences among the three groups (P<0.05), while other parameters showed no differences. ROC curves illustrated that independent ocular parameters such as LT, HCS-WTW, and ACD had clinical predictive diagnostic significance for low vault abnormalities. The area under the curve (AUC), sensitivity, and specificity for these parameters were 0.829(0.952, 0.561), 0.745(0.857, 0.644), and 0.730(0.619, 0.853), respectively. The diagnostic cut-off values were 3.745, 0.020, and 2.975 mm, respectively. The clinical predictive significance of independent ocular parameters in diagnosing the high vault group was poor (AUC<0.7). The predictive Logistic model equation for low vault was Logistic(V1)=-10.067+5.328·HCS-3.620·WTW+6.263·LT, and the predictive model for high vault was Logistic(V2)=6.232+1.323·WTW-3.358·LT. The new parameters in the predictive equation significantly improved the diagnostic efficiency of low and high vault abnormalities, reaching 0.884(0.810, 0.824) and 0.736(0.810, 0.554), respectively. Conclusions: Preoperative predictive diagnostic parameters for postoperative low vault group included LT, HCS-WTW, and ACD, while the high vault group had no independent predictive diagnostic parameters. Logistic regression improved the predictive diagnostic efficiency of abnormal vaults.


Asunto(s)
Miopía , Lentes Intraoculares Fáquicas , Humanos , Estudios Retrospectivos , Miopía/cirugía , Miopía/diagnóstico , China , Cámara Anterior
20.
Arkh Patol ; 85(3): 54-63, 2023.
Artículo en Ruso | MEDLINE | ID: mdl-37272441

RESUMEN

OBJECTIVE: To study the effect of the repair stimulator alpha-glutamyl-tryptophan on the morphological characteristics of the gastric mucosa and the expression of CXCL-12 and CDX-2 in chronic atrophic gastritis associated with Helicobacter pylori. MATERIAL AND METHODS: Biopsy samples of 116 patients with a verified diagnosis of chronic atrophic gastritis associated with Helicobacter pylori were analyzed in a multicenter double-blind randomized placebo-controlled study. During the morphological study, the parameters characterizing the process of atrophy were evaluated: the number of glands per 1 mm2 of the gastric mucosa, the depth of the gastric mucosa glands, the number of parietal cells per 100 epithelial cells of the gastric mucosa, and the presence of signs of intestinal metaplasia. Primary antibodies Anti-CXCL-12 (MA5-23759) and Anti-CDX-2 (EP25) were used to set up immunohistochemical reactions to verify the expression of CXCL-12 and CDX-2. RESULTS: In patients taking the studied drug, a statistically significant increase in the number of glands per 1 mm2 of the gastric mucosa was revealed when compared with the initial screening indicators by 26.1% (p=0.028) and with the placebo group (p=0.026), a tendency to decrease the signs of intestinal metaplasia was determined. There was a statistically significant increase in the expression in the relative area of CXCL-12 expression in patients taking placebo when compared with the parameters of the initial data (p=0.045) and the absence of statistically significant changes in the main group. A statistically significant increase in the relative area of the CDX-2 expression was revealed in the group taking alpha-glutamyl-tryptophan in comparison with the baseline data (p=0.015), no statistically significant dynamics of this indicator was found in the placebo group. CONCLUSION: A statistically significant positive effect of the study drug on regenerative mechanisms leading to stabilization and/or improvement of the histological picture in the atrophic area of the gastric mucosa was found in comparison with the control of the initial state and with placebo. The results of an immunohistochemical study to increase CDX-2 expression while taking the study drug can also be regarded as an indicator of improvement in reparative processes.


Asunto(s)
Gastritis Atrófica , Infecciones por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Gastritis Atrófica/tratamiento farmacológico , Gastritis Atrófica/genética , Gastritis Atrófica/complicaciones , Triptófano/análisis , Triptófano/metabolismo , Triptófano/uso terapéutico , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/patología , Mucosa Gástrica/patología , Metaplasia/patología , Neoplasias Gástricas/patología
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