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1.
J Clin Ultrasound ; 51(8): 1312-1317, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37667623

RESUMEN

PURPOSE: To analyze the clinical values of echocardiography combined with vascular ultrasound in the diagnosis of aortic dissection according to the DeBakey classification. METHODS: The clinical data of 77 patients with aortic dissection admitted to our hospital from August 2016 to January 2022 were retrospectively analyzed. All patients were examined with ultrasound and CT angiography (CTA), the consistency between ultrasound and CTA ± intraoperative diagnosis for the classification of AD was checked, as well as the differences in ultrasound signs and Ultrasound parameters between different types of AD were analyzed. RESULTS: The results of Kappa value: There was a high level of agreement between echocardiography combined with transabdominal vascular ultrasound and CTA ± intraoperative diagnosis for the classification of AD (Kappa = 0.897, p = 0.000). In the ultrasound signs, the proportion of pericardial effusion, aortic regurgitation, aortic widening, and coronary artery involvement in type DeBakey I and II aortic dissection was significantly higher than that in Type III. There was no significant difference in the proportion of intimal floating, true and false lumen, and intimal rupture in Types I, II, and III aortic dissections. In the comparison of ultrasound parameters, there is a statistically significant difference in the values of LAD (left atrial diameter), LAV (left atrial volume), and LVEDD (left ventricular end-diastolic diameter) among different types of aortic dissection. There is no significant difference in IVS (interventricular septum thickness), LVPW (left ventricular posterior wall thickness), LVEF (left ventricular ejection fraction), and E/e' ratio among different types of aortic dissection. CONCLUSION: Echocardiography combined with transabdominal vascular ultrasound can accurately evaluate aortic dissection with real-time dynamic images and provide important clinical significance for early individualized treatment of patients through accurate classification of different aortic dissection.


Asunto(s)
Disección Aórtica , Función Ventricular Izquierda , Humanos , Volumen Sistólico , Estudios Retrospectivos , Disección Aórtica/diagnóstico por imagen , Ecocardiografía
2.
Arch Gerontol Geriatr ; 125: 105486, 2024 10.
Artículo en Inglés | MEDLINE | ID: mdl-38761527

RESUMEN

BACKGROUND: Osteoporosis and sarcopenia are common age-related conditions characterized by the progressive loss of bone density and muscle mass, respectively. Their co-occurrence, often referred to as osteosarcopenia, presents significant challenges in elderly care due to increased fragility and functional impairment. Existing studies have identified shared pathological mechanisms between these conditions, including inflammation, hormonal imbalances, and metabolic dysregulation, but a comprehensive understanding of their molecular interplay remains incomplete. OBJECTIVE: This study aims to deepen our understanding of the molecular interactions between sarcopenia and osteoporosis through an integrated omics approach, revealing potential therapeutic targets and biomarkers. METHODS: Employing a combination of proteomics and transcriptomics analyses, this study analyzed bone and muscle tissue samples from patients diagnosed with osteoporosis and osteosarcopenia. Techniques included high-throughput sequencing and label-free proteomics, supported by advanced bioinformatics tools for data analysis and functional annotation of genes and proteins. RESULTS: The study found marked differences in gene and protein expressions between osteoporosis and osteosarcopenia tissues. Specifically, genes like PDIA5, TUBB1, and CYFIP2 in bone, along with MYH7 and NCAM1 in muscle, exhibited differential expression at both mRNA and protein levels. Pathway analyses revealed the significance of oxidative-reduction balance, cellular metabolism, and immune response in the progression of these conditions. Importantly, the study pinpointed osteoclast differentiation and NF-kappa B signaling pathways as critical in the molecular dynamics of osteosarcopenia, suggesting potential targets for therapy. CONCLUSIONS: This study utilized transcriptomics and proteomics to identify key genes and proteins impacting sarcopenia and osteoporosis, employing advanced network tools to delineate interaction networks and crucial signaling pathways. It highlighted genes like PDIA5 and TUBB1, consistently expressed in both analyses, involved in pathways such as osteoclast differentiation and cytokine interactions. These insights enhance understanding of the molecular interplay in bone and muscle degeneration with aging, suggesting directions for future research into therapeutic interventions and prevention strategies for age-related degenerative diseases.


Asunto(s)
Osteoporosis , Proteómica , Sarcopenia , Transcriptoma , Humanos , Sarcopenia/metabolismo , Sarcopenia/genética , Osteoporosis/genética , Osteoporosis/metabolismo , Anciano , Masculino , Femenino , Persona de Mediana Edad , Biomarcadores/metabolismo
3.
Materials (Basel) ; 16(2)2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36676282

RESUMEN

LT21 a type of aluminum alloy used for the irradiation channel of the first heavy water research reactor (HWRR) in China. Studying the mechanical property of irradiated LT21 aluminum under actual service conditions is essential for evaluating its application property. In this paper, tensile specimens of irradiated LT21 were manufactured from the decommissioned irradiation channel of an HWRR; then, tensile tests were carried out, and then the fracture surfaces were observed. The effect of neutron irradiation on tensile behavior and the failure mechanism was analyzed by comparing the result of irradiated and unirradiated LT21 specimens. The results show that, with the thermal neutron flux increasing to 2.38 × 1022 n/cm2, the YS gradually increased from the initial 158 MPa to 251 MPa, the UTS increased from 262 MPa to 321 MPa, and the elongation decreased from 28.8% to about 14.3%; the brittle fracture of the LT21 specimen appeared after irradiation, and the proportion of brittle fracture increased as the neutron fluence increased; the nanophase structures, with a size of less than 50 nm, were precipitated in the LT21 aluminum alloy after neutron irradiation. Transmutation Si is presumed to be the main cause of the radiation effect mechanism of LT21.

4.
RSC Adv ; 13(51): 36424-36429, 2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38099260

RESUMEN

In order to promote the wide application of clean energy-fuel cells, it is urgent to develop transition metal-based high-efficiency oxygen reduction reaction (ORR) catalytic materials with a low cost and available rich raw material resources to replace the currently used precious metal platinum-based catalytic materials. Herein, a novel 'active-site-anchoring' strategy was developed to synthesize highly-activated carbon-based ORR catalysts. Firstly, poly(p-phenylene benzobisoxazole) (PBO) fiber with a stable chemical structure was selected as the main precursor, and iron was complexed on its surface, and then poly-dopamine (PDA) was coated on the surface of PBO-Fe to form a PBO-Fe-PDA composite structure. Therefore, carbon-based catalyst PBO-Fe-PDA-900 with abundant Fe2O3 active sites was prepared by anchoring iron sites by PDA after pyrolysis. As a result, the PBO-Fe-PDA-900 catalyst displayed a 30 mV higher half-wave potential (0.86 V) than that of a commercial Pt/C electrocatalyst. Finally, PBO-Fe-PDA-900 was used as a cathode material for zinc-air batteries, showing a high peak power density superior to Pt/C. This work offers new prospects for the design of efficient, non-precious metal-based materials in zinc-air batteries.

5.
RSC Adv ; 12(51): 33329-33339, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36425195

RESUMEN

The graphene oxide (GO) and polyethylene terephthalate (PET) molecular chains are connected together by the two amino groups of the crosslinking agent p-phenylenediamine (PPD). The presence of macromolecular chains could make GO uniformly dispersed in the polymer matrix, improving the antistatic performance and thermal stability of the nanocomposite. In this paper, GO was prepared by the improved Hummers, method. In the first step, an amine group of PPD undergoes a nucleophilic ring-opening reaction with an epoxy group on GO. Multiple characterization methods indicate that PPD is successfully grafted to the surface of GO sheets and GO is partially reduced simultaneously. The graphene layer spacing increased from 0.81 nm for GO to 1.49 nm for grafted graphene oxide (g-GO). The number of oxygen-containing functional groups in GO is also reduced. The conductivity of g-GO at room temperature is 1.8 S cm-1, which is much higher than that of GO. In addition, the thermal stability of g-GO has also been improved. In the second step, the other unreacted terminal amino group of PPD is grafted to PET molecular chains through hydrogen bonding or amidation reactions. Antistatic and thermally stable nanocomposites were then obtained by hot pressing. Different ratios of graphene/polyester nanocomposites were obtained. At the same time, the g-GO is further thermally reduced. The thermal stability of PET/g-GO nanocomposite has been greatly improved, while the thermal stability of PET/GO nanocomposite is basically the same as that of pure PET. For the PET/g-GO nanocomposite, the residue rate has increased by nearly 10%, and the maximum thermal decomposition temperature has also increased by 11 °C. When the content of g-GO is 1.0 vol%, the bulk conductivity of PET/g-GO nanocomposite is increased by 8 orders of magnitude. However, when the content of GO is 1.0 vol%, the bulk conductivity of the PET/GO nanocomposite is only improved by 3 orders of magnitude. PET/g-GO nanocomposites exhibit good antistatic properties. The PET/g-GO nanocomposite's conductive percolation threshold is 0.61 vol%, while that of the PET/GO nanocomposite is 1.64 vol%. The electrical conductivity of the nanocomposite increases with the increase of graphene content. And the well-dispersed modified graphene can improve the electrical conductivity of the nanocomposite.

6.
Mol Plant ; 15(4): 689-705, 2022 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-35032687

RESUMEN

Arthropod-borne viruses cause serious threats to human health and global agriculture by rapidly spreading via insect vectors. Southern rice black-streaked dwarf virus (SRBSDV) is the most damaging rice-infecting virus that is frequently transmitted by planthoppers. However, the molecular mechanisms underlying its propagation in the host plants and epidemics in the field are largely unknown. Here, we showed that the SRBSDV-encoded P6 protein is a key effector that regulates rice ethylene signaling to coordinate viral infection and transmission. In early SRBSDV infection, P6 interacts with OsRTH2 in the cytoplasm to activate ethylene signaling and enhance SRBSDV proliferation; this also repels the insect vector to reduce infestation. In late infection, P6 enters the nucleus, where it interacts with OsEIL2, a key transcription factor of ethylene signaling. The P6-OsEIL2 interaction suppresses ethylene signaling by preventing the dimerization of OsEIL2, thereby facilitating viral transmission by attracting the insect vector. Collectively, these findings reveal a novel molecular mechanism by which an arbovirus modulates the host defense system to promote viral infection and transmission.


Asunto(s)
Hemípteros , Oryza , Virosis , Animales , Etilenos , Hemípteros/metabolismo , Insectos Vectores , Oryza/metabolismo , Enfermedades de las Plantas , Proteínas Virales/metabolismo
8.
Front Microbiol ; 12: 684591, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34335511

RESUMEN

Antibiotic-resistant ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) has become a serious threat to public health worldwide. Cationic α-helical antimicrobial peptides (CαAMPs) have attracted much attention as promising solutions in post-antibiotic era. However, strong hemolytic activity and in vivo inefficacy have hindered their pharmaceutical development. Here, we attempt to address these obstacles by investigating BmKn2 and BmKn2-7, two scorpion-derived CαAMPs with the same hydrophobic face and a distinct hydrophilic face. Through structural comparison, mutant design and functional analyses, we found that while keeping the hydrophobic face unchanged, increasing the number of alkaline residues (i.e., Lys + Arg residues) on the hydrophilic face of BmKn2 reduces the hemolytic activity and broadens the antimicrobial spectrum. Strikingly, when keeping the total number of alkaline residues constant, increasing the number of Lys residues on the hydrophilic face of BmKn2-7 significantly reduces the hemolytic activity but does not influence the antimicrobial activity. BmKn2-7K, a mutant of BmKn2-7 in which all of the Arg residues on the hydrophilic face were replaced with Lys, showed the lowest hemolytic activity and potent antimicrobial activity against antibiotic-resistant ESKAPE pathogens. Moreover, in vivo experiments indicate that BmKn2-7K displays potent antimicrobial efficacy against both the penicillin-resistant S. aureus and the carbapenem- and multidrug-resistant A. baumannii, and is non-toxic at the antimicrobial dosages. Taken together, our work highlights the significant functional disparity of Lys vs Arg in the scorpion-derived antimicrobial peptide BmKn2-7, and provides a promising lead molecule for drug development against ESKAPE pathogens.

9.
J Immunol ; 181(7): 4798-806, 2008 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-18802083

RESUMEN

Although microbial (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMBPP) can activate primate Vgamma2Vdelta2 T cells, molecular mechanisms by which HMBPP interacts with Vgamma2Vdelta2 T cells remain poorly characterized. Here, we developed soluble, tetrameric Vgamma2Vdelta2 TCR of rhesus macaques to define HMBPP/APC interaction with Vgamma2Vdelta2 TCR. While exogenous HMBPP was associated with APC membrane in an appreciable affinity, the membrane-associated HMBPP readily bound to the Vgamma2Vdelta2 TCR tetramer. The Vgamma2Vdelta2 TCR tetramer was shown to bind stably to HMBPP presented on membrane by various APC cell lines from humans and nonhuman primates but not those from mouse, rat, or pig. The Vgamma2Vdelta2 TCR tetramer also bound to the membrane-associated HMBPP on primary monocytes, B cells and T cells. Consistently, endogenous phosphoantigen produced in Mycobacterium-infected dendritic cells was transported and presented on membrane, and bound stably to the Vgamma2Vdelta2 TCR tetramer. The capability of APC to present HMBPP for recognition by Vgamma2Vdelta2 TCR was diminished after protease treatment of APC. Thus, our studies elucidated an affinity HMBPP-APC association conferring stable binding to the Vgamma2Vdelta2 TCR tetramer and the protease-sensitive nature of phosphoantigen presentation. The findings defined APC presentation of phosphoantigen HMBPP to Vgamma2Vdelta2 TCR.


Asunto(s)
Presentación de Antígeno/inmunología , Células Presentadoras de Antígenos/inmunología , Células Presentadoras de Antígenos/metabolismo , Antígenos Bacterianos/metabolismo , Organofosfatos/metabolismo , Fosfoproteínas/metabolismo , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Secuencia de Aminoácidos , Animales , Presentación de Antígeno/genética , Antígenos Bacterianos/biosíntesis , Antígenos Bacterianos/inmunología , Línea Celular , Línea Celular Tumoral , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Células Dendríticas/microbiología , Dimerización , Humanos , Macaca mulatta , Ratones , Datos de Secuencia Molecular , Organofosfatos/química , Organofosfatos/inmunología , Fosfoproteínas/inmunología , Unión Proteica/inmunología , Ratas , Receptores de Antígenos de Linfocitos T gamma-delta/biosíntesis , Receptores de Antígenos de Linfocitos T gamma-delta/genética , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Porcinos , Células U937
10.
Bioresour Technol ; 292: 121917, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31408778

RESUMEN

Nitrogen pollution in aquaculture needs the efficient and cost-effective in-situ technology. This study aims to apply Marichromatium gracile YL28 to in-situ bioremediation and test its ability to maintain the nitrogen balance in aquaculture. In laboratory aquaculture system, approximately 99.96% of nitrite (1 mg/L) was removed within 7 d through denitrification coupled with assimilatory nitrate reduction. Ammonium (3.5 mg/L) of 95.6% was directly assimilated by YL28 within 7 d. Moreover, in zero exchange water from shrimp (Penaeus vannamei) aquaculture field trials (20 days), YL28 significantly reduced the ammonium accumulation (0.6 mg/L) and 99.3% of nitrite (1.25 mg/L). Toxicological studies with the Institute of Cancer Research (ICR) mice and Oryzias melastigma indicated that M. gracile YL28 can be safely applied in aquatic ecosystems. All results demonstrate that strain YL28 has high promise for future applications of removing inorganic nitrogen and maintaining the nitrogen balance from in-situ aquaculture.


Asunto(s)
Nitrógeno , Estanques , Animales , Acuicultura , Desnitrificación , Ecosistema , Ratones
11.
Int J Biostat ; 12(2)2016 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-27838682

RESUMEN

The Bland-Altman method has been widely used for assessing agreement between two methods of measurement. However, it remains unsolved about sample size estimation. We propose a new method of sample size estimation for Bland-Altman agreement assessment. According to the Bland-Altman method, the conclusion on agreement is made based on the width of the confidence interval for LOAs (limits of agreement) in comparison to predefined clinical agreement limit. Under the theory of statistical inference, the formulae of sample size estimation are derived, which depended on the pre-determined level of α, ß, the mean and the standard deviation of differences between two measurements, and the predefined limits. With this new method, the sample sizes are calculated under different parameter settings which occur frequently in method comparison studies, and Monte-Carlo simulation is used to obtain the corresponding powers. The results of Monte-Carlo simulation showed that the achieved powers could coincide with the pre-determined level of powers, thus validating the correctness of the method. The method of sample size estimation can be applied in the Bland-Altman method to assess agreement between two methods of measurement.


Asunto(s)
Método de Montecarlo , Tamaño de la Muestra , Biometría , Humanos , Reproducibilidad de los Resultados
12.
Colloids Surf B Biointerfaces ; 100: 163-8, 2012 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22766293

RESUMEN

While granulysin has been suggested to play an important role in adaptive immune responses against bacterial infections by killing pathogens, and molecular force for protein-protein interaction or protein-bacteria interaction may designate the specific functions of a protein, the molecular-force basis underlying the bacteriolytic effects of granulysin at single-molecule level remains unknown. Here, we produced and purified bactericidal domain of macaque granulysin (GNL). Our bacterial lysis assays suggested that GNL could efficiently kill bacteria such as Listeria monocytogenes. Furthermore, we found that the interaction force between GNL and L. monocytogenes measured by an atomic force microscopy (AFM) was about 22.5 pN. Importantly, our AFM-based single molecular analysis suggested that granulysin might lyse the bacteria not only through electrostatic interactions but also by hydrogen bonding and van der Waals interaction. Thus, this work provides a previous unknown mechanism for bacteriolytic effects of granulysin.


Asunto(s)
Antibacterianos/química , Antígenos de Diferenciación de Linfocitos T/química , Listeria monocytogenes/efectos de los fármacos , Silicatos de Aluminio/química , Animales , Antibacterianos/farmacología , Antígenos de Diferenciación de Linfocitos T/farmacología , Bacteriólisis , Células Inmovilizadas , Recuento de Colonia Microbiana , Escherichia coli/genética , Enlace de Hidrógeno , Listeria monocytogenes/crecimiento & desarrollo , Macaca , Microscopía de Fuerza Atómica , Perforina/farmacología , Estructura Terciaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacología , Electricidad Estática
13.
PLoS One ; 4(9): e6905, 2009 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-19730727

RESUMEN

BACKGROUND: In vivo kinetics and frequencies of epitope-specific CD4 T cells in lymphoid compartments during M. tuberculosis infection and their resting memory pool after BCG vaccination remain unknown. METHODOLOGY/FINDINGS: Macaque DR*W201 tetramer loaded with Ag85B peptide 65 was developed to directly measure epitope-specific CD4 T cells in blood and tissues form macaques after M. tuberculosis infection or BCG vaccination via direct staining and tetramer-enriched approach. The tetramer-based enrichment approach showed that P65 epitope-specific CD4 T cells emerged at mean frequencies of approximately 500 and approximately 4500 per 10(7) PBL at days 28 and 42, respectively, and at day 63 increased further to approximately 22,000/10(7) PBL after M. tuberculosis infection. Direct tetramer staining showed that the tetramer-bound P65-specific T cells constituted about 0.2-0.3% of CD4 T cells in PBL, lymph nodes, spleens, and lungs at day 63 post-infection. 10-fold expansion of these tetramer-bound epitope-specific CD4 T cells was seen after the P65 peptide stimulation of PBL and tissue lymphocytes. The tetramer-based enrichment approach detected BCG-elicited resting memory P65-specific CD4 T cells at a mean frequency of 2,700 per 10(7) PBL. SIGNIFICANCE: Our work represents the first elucidation of in vivo kinetics and frequencies for tetramer-bound epitope-specific CD4 T cells in the blood, lymphoid tissues and lungs over times after M. tuberculosis infection, and BCG immunization.


Asunto(s)
Vacuna BCG/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Epítopos/química , Antígenos HLA-DR/química , Memoria Inmunológica/inmunología , Mycobacterium tuberculosis/metabolismo , Tuberculosis Pulmonar/inmunología , Tuberculosis/inmunología , Alelos , Animales , Proliferación Celular , Epítopos de Linfocito T/química , Cinética , Macaca mulatta , Péptidos/química
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