Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.415
Filtrar
1.
Sci Total Environ ; 806(Pt 3): 151290, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34743874

RESUMO

With the increasing application of tetracycline (TC) in medical treatment, animal husbandry and aquaculture in recent decades, high quantities of TC have been frequently detected in the aquatic environment, and accordingly TC-related toxicity and environmental pollution have become a global concern. The present study was performed to explore the toxicological influences of TC exposure at its environmentally relevant concentrations on the gills of tilapia Oreochromis niloticus, based on the alteration in histopathology, oxidative stress, inflammatory response, cell cycle, mitochondrial function, apoptosis, and transcriptomic analysis. Our findings revealed that TC exposure damaged the structure and function, induced oxidative stress, affected inflammatory responses, and reduced Na+/K+-ATPase (NKA) activity in the gills. TC also caused the inhibition in cell cycle, resulted in mitochondrial dysfunction and activated apoptosis. Further transcriptomic analysis indicated the extensive influences of TC exposure on the gill function, and immune system was the main target to waterborne TC exposure. These results elucidated that environmental TC had more complex toxicological effects on gills of fish than previously assessed, and provided novel insight into molecular toxicology of TC on fish and good basis for assessing the environmental risk of TC.

2.
Cryobiology ; 2021 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-34848188

RESUMO

To overcome the shortage of organ donors and morbidity and mortality caused by lifetime immunosuppression, development of a transplantable graft to permanently replace the organ function is required. This study is focused on the effects of a freeze-thaw process and cryoprotectants on the ultrastructure and composition of decellularization scaffolds. Results showed that cryoprotectants and freezing temperatures had significant effects on the decellularization scaffold. The vascular network integrity at -20 °C was better than that at -80 °C. For low-concentration cryoprotectants, 10% dimethyl sulfoxide and 5% trehalose could achieve a better balance between preserving the vascular tree and decellularization. For high-concentration cryoprotectants (vitrification solutions VS55 and VS83), the vascular network integrity was best because of the absence of freezing damage and ice-induced disruption of cells, but the decellularization effect was poor because the cells remained in the scaffold. Collagen, elastic fiber, protein, and mechanical properties of the scaffold could be retained after decellularization using the freeze-thaw method. Further studies and further optimization of the freeze-thaw decellularization protocol are necessary for clinical applications.

3.
J Neurointerv Surg ; 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34753811

RESUMO

OBJECTIVE: To evaluate predictors of unfavorable outcome in stent-assisted coiling for symptomatic unruptured intracranial spontaneous vertebral artery dissecting aneurysms (uis-VADAs) based on 608 reconstructed lesions in 30 medical centres. METHODS: A total of 608 patients (male:female=479:129; mean age, 53.26±10.26 years) with 608 symptomatic uis-VADAs underwent reconstructive treatments using stent(s) with coils between January 2009 and December 2015. Treatments and predictors of unfavorable outcomes were retrospectively analyzed. RESULTS: Mainly, three methods were used to treat patients with uis-VADAs, including routine single-stent in 208 patients (such as Enterprise and others), new low-profile LVIS single stent in 107 patients, and multiple stents in 293 patients. During the median 66 months of clinical follow-up, 14 patients died, and 16 of the remaining 594 survivors had unfavorable outcomes (modified Rankin Scale score 3-5). The overall mortality rate was 2.3% (14/608), and the unfavorable outcome (mRS score 3-6) rate was 4.9% (30/608). Multivariate logistic regression analysis indicated that preprocedural ischemic infarctions (OR=3.78; 95% CI 1.52 to 9.40; p<0.01), diabetes mellitus (OR=3.74; 95% CI 1.31 to 10.68; p=0.01), and procedural complications (OR=14.18; 95% CI 5.47 to 36.80; p<0.01) were predictors of unfavorable outcome in the reconstructed VADAs. CONCLUSIONS: This multicenter study indicated that preprocedural ischemic infarctions, diabetes mellitus, and procedural complications were related to unfavorable clinical outcomes in the reconstructed uis-VADAs.

4.
Perioper Med (Lond) ; 10(1): 37, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34743734

RESUMO

BACKGROUND: Homocysteine, folate, and vitamin B12 involved in 1-carbon metabolism are associated with cognitive disorders. We sought to investigate the relationships between these factors and delayed neurocognitive recovery (dNCR) after non-cardiac surgery. METHODS: This was a prospective observational study of patients (n = 175) who were ≥ 60 years of age undergoing non-cardiac surgery. Patients were evaluated preoperatively and for 1 week postoperatively by using neuropsychological tests and were divided into dNCR or non-dNCR groups according to a Z-score ≤ - 1.96 on at least two of the tests. The relationship between the occurrence of dNCR and preoperative levels of homocysteine, folate, and vitamin B12 was analyzed. Univariate and multivariable logistic regression analyses were conducted to identify factors associated with dNCR. RESULTS: Delayed neurocognitive recovery was observed in 36 of 175 patients (20.6%; 95% confidence interval [CI], 14.5-26.6%) 1 week postoperatively. Patients who developed dNCR had significantly higher median [interquartile range (IQR)] homocysteine concentrations (12.8 [10.9,14.4] µmol/L vs 10.6 [8.6,14.7] µmol/L; P = 0.02) and lower folate concentrations (5.3 [4.2,7.3] ng/mL vs 6.9 [5.3,9.5] ng/mL; P = 0.01) than those without dNCR. Compared to the lowest tertile, the highest homocysteine tertile predicted dNCR onset (odds ratio [OR], 3.9; 95% CI, 1. 3 to 11.6; P = 0.02), even after adjusting for age, sex, education, and baseline Mini Mental State Examination. CONCLUSIONS: Elderly patients with high homocysteine levels who underwent general anesthesia for non-cardiac surgery have an increased risk of dNCR. This knowledge could potentially assist in the development of preventative and/or therapeutic measures. TRIAL REGISTRATION: NCT03084393 ( https://www.clinicaltrials.gov ).

5.
Psychol Health Med ; : 1-9, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34758658

RESUMO

The rapid development of the coronavirus disease 2019 (COVID-19) outbreak has brought great harm to physical and mental health of the public. This study aims to investigate the psychological status and sleep quality of the Chinese public during the outbreak of the COVID-19 and its related factors. The survey was conducted from February 17th to February 26th, 2020 in southwestern China. The snowball sampling method was used to invite subjects. Demographic data were collected, and mental status and sleep quality were assessed by the Generalized Anxiety Disorder-7 Scale (GAD-7), the Patient Health Questionnaire-9 (PHQ-9), and the Pittsburgh Sleep Quality Index (PSQI). Descriptive, univariate, and correlation analyses were used to investigate risk factors for psychological status and sleep patterns. A total of 1509 adults (713 males and 796 females) were enrolled in this study. The overall prevalence of anxiety, depression, and decreased sleep quality were 22.3%, 32.2% and 35.4%, respectively. Compared with females, male population has witnessed a higher prevalence of anxiety symptoms (25.1% vs 20.4%, P= 0.007) and depressive symptoms (34.6% vs 30.0%, P= 0.027). In addition, age, marital status, living situation, involvement in anti-pandemic work, basic health status and work status were significant risk factors for anxiety or depression (P< 0.05). During the COVID-19 outbreak, psychological problems and sleep disorders were prevalent among the Chinese public. More attention should be paid to males, the elderly, the solitary, the unemployed, front-line workers in pandemic prevention, and patients with chronic diseases.

6.
J Xray Sci Technol ; 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34744047

RESUMO

BACKGROUND: Energetics alteration plays a crucial role in the myocardial injury process in chronic hypoxia diseases (CHD). 31P magnetic resonance spectroscopy (MRS) can investigate alterations in cardiac energetics in vivo. OBJECTIVE: To characterize the potential value of 31P MRS in evaluating cardiac energetics alteration of chronic hypoxic rats (CHRs). METHODS: Twenty-four CHRs were induced by SU5416 combined with hypoxia and divided into four groups according to the modeling time of one, two, three and five weeks, respectively. Control group also contains six rats. 31P MRS was performed weekly and the ratio of concentrations of phosphocreatine (PCr) to adenosine triphosphate (ATP) (PCr/ATP) was obtained. In addition, the cardiac structure index and systolic function parameters, including the right ventricular ejection fraction (RVEF), right ventricular end-diastolic volume index (RVEDVi), right ventricular end-systolic volume index (RVESVi), and the left ventricular function parameters, were measured. RESULTS: Decreased resting cardiac PCr/ATP ratio in CHRs was observed at the first week, compared to the control group (2.90±0.35 vs. 3.31±0.45, p = 0.045), while the RVEF, RVEDVi, and RVESVi decreased at the second week (p < 0.05). The PCr/ATP ratio displayed a significant correlation with RVEF (r = 0.605, p = 0.001), RVEDVi, and RVESVi (r = -0.661, r = -0.703; p < 0.001). CONCLUSIONS: 31P MRS can easily detect the cardiac energetics alteration in a CHR model before the onset of ventricular dysfunction. The decreased PCr/ATP ratio likely reveales myocardial injury and cardiac dysfunction.

8.
J Biochem Mol Toxicol ; : e22951, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34791735

RESUMO

Quercetin has been preliminarily proven to serve as a potential agent for the treatment of osteoarthritis (OA). However, its effects and potential mechanisms on the pathological process of OA are not very clear. This study aimed to study the protective effect of quercetin on OA. Lipopolysaccharide (LPS)-treated chondrocytes (C28/I2 cell) and anterior cruciate ligament transection with partial medial meniscectomy-treated Wistar rats were used as models of OA in vitro and in vivo. Cell counting kit-8 (CCK-8 kit), flow cytometry, enzyme-linked immunosorbent assay (ELISA) kit, western blot, dichlorodihydrofluorescein diacetate (DCFH-DA) kit, thiobarbituric acid (TBA) test, toluidine blue staining, Hematoxylin eosin (HE) staining and terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling (TUNEL) staining were used to evaluate cell viability, cell apoptosis, inflammatory cytokines level, protein expression, reactive oxygen species (ROS) level, malondialdehyde (MDA) content, morphological changes, and chondrocyte apoptosis of cartilage, respectively. Results showed that quercetin could reduce LPS-induced C28/I2 cell apoptosis, extracellular matrix (ECM) degradation, and cell pyroptosis, and overexpression of nucleotide-binding domain and leucine-rich-repeat-containing (NLR) family, pyrin domain-containing 3 (NLRP3) revealed that quercetin reduced chondrocyte apoptosis and ECM degradation by inhibiting NLRP3-mediated pyroptosis. Furthermore, quercetin could reduce chondrocyte apoptosis and ECM degradation, and inhibit NLRP3-mediated pyroptosis through blocking oxidative stress. It was further confirmed in the rat OA model that quercetin alleviated OA by blocking oxidative stress, reduces chondrocyte pyroptosis, apoptosis, and ECM degradation. In conclusion, quercetin inhibited OA via blocking oxidative stress-induced chondrocyte pyroptosis in models of OA in vitro and in vivo.

9.
PLoS One ; 16(11): e0259563, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34784377

RESUMO

microRNAs (miRNA) in extracellular vesicles (EVs) have been investigated as potential biomarkers for pancreatic ductal adenocarcinoma (PDAC). However, a mixed population of EVs is often obtained using conventional exosome isolation methods for biomarker development. EVs are derived from different cellular processes and present in various sizes, therefore miRNA expression among them is undoubtedly different. We developed a simple protocol utilizing sequential filtration and ultracentrifugation to separate PDAC EVs into three groups, one with an average diameter of more than 220 nm, named operational 3 (OP3); one with average diameters between 100-220 nm, named operational 2 (OP2); and another with average diameters around 100 nm, named operational 1 (OP1)). EVs were isolated from conditioned cell culture media and plasma of human PDAC xenograft mice and early stage PDAC patients, and verified by nanoparticle tracking, western blot, and electronic microscopy. We demonstrate that exosome specific markers are only enriched in the OP1 group. qRT-PCR analysis of miRNA expression in EVs from PDAC cells revealed that expression of miR-196a and miR-1246, two previously identified miRNAs highly enriched in PDAC cell-derived exosomes, is significantly elevated in the OP1 group relative to the other EV groups. This was confirmed using plasma EVs from PDAC xenograft mice and patients with localized PDAC. Our results indicate that OP1 can be utilized for the identification of circulating EV miRNA signatures as potential biomarkers for PDAC.

12.
Rev Assoc Med Bras (1992) ; 67(9): 1342-1348, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34816932

RESUMO

OBJECTIVE: This study aimed to assess the effect of the collagen/silk fibroin scaffolds seeded with human umbilical cord-mesenchymal stem cells on functional recovery after acute complete spinal cord injury. METHODS: The fibroin and collagen were mixed (mass ratio, 3:7), and the composite scaffolds were produced. Forty rats were randomly divided into the Sham group (without spinal cord injury), spinal cord injury group (spinal cord transection without any implantation), collagen/silk fibroin scaffolds group (spinal cord transection with implantation of the collagen/silk fibroin scaffolds), and collagen/silk fibroin scaffolds + human umbilical cord-mesenchymal stem cells group (spinal cord transection with the implantation of the collagen/silk fibroin scaffolds co-cultured with human umbilical cord-mesenchymal stem cells). Motor evoked potential, Basso-Beattie-Bresnahan scale, modified Bielschowsky's silver staining, and immunofluorescence staining were performed. RESULTS: The BBB scores in the collagen/silk fibroin scaffolds + human umbilical cord-mesenchymal stem cells group were significantly higher than those in the spinal cord injury and collagen/silk fibroin scaffolds groups (p<0.05 or p<0.01). The amplitude and latency were markedly improved in the collagen/silk fibroin scaffolds + human umbilical cord-mesenchymal stem cells group compared with the spinal cord injury and collagen/silk fibroin scaffolds groups (p<0.05 or p<0.01). Meanwhile, compared to the spinal cord injury and collagen/silk fibroin scaffolds groups, more neurofilament positive nerve fiber ensheathed by myelin basic protein positive structure at the injury site were observed in the collagen/silk fibroin scaffolds + human umbilical cord-mesenchymal stem cells group (p<0.01, p<0.05). The results of Bielschowsky's silver staining indicated more nerve fibers was observed at the lesion site in the collagen/silk fibroin scaffolds + human umbilical cord-mesenchymal stem cells group compared with the spinal cord injury and collagen/silk fibroin scaffolds groups (p<0.01, p< 0.05). CONCLUSION: The results demonstrated that the transplantation of human umbilical cord-mesenchymal stem cells on a collagen/silk fibroin scaffolds could promote nerve regeneration, and recovery of neurological function after acute spinal cord injury.


Assuntos
Fibroínas , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Traumatismos da Medula Espinal , Animais , Colágeno , Humanos , Ratos , Recuperação de Função Fisiológica , Medula Espinal , Tecidos Suporte , Cordão Umbilical
13.
Opt Express ; 29(23): 37443-37452, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34808815

RESUMO

In this paper, we report that the conversion efficiency and spectrum of femtosecond optical parametric amplification (fs-OPA) can be significantly enhanced by employing a compact cascaded femtosecond OPA (CF-OPA) scheme with the self-compensation of the temporal walk-off between two nonlinear gain media. Correspondingly, the gain related temporal contrast can also be improved. The feasibility of the CF-OPA method using three cascaded BBO crystals is numerically and experimentally analyzed. Moreover, by replacing the conventional fs-OPA with the CF-OPA and optimizing the design, the performance of a nonlinear temporal filter combining cross-polarized wave generation and fs-OPA is comprehensively improved. The experimental results demonstrate the superiority of the CF-OPA scheme, which can generate high-performance cleaned pulses at 1 kHz repetition rate with energy of 340µJ, energy fluctuation below 0.9% (RMS), spectral width of 97 nm (FWHM), Fourier-transform-limited pulse width of 12 fs and temporal contrast better than 10-12. To the best of our knowledge, this is the first reported temporal walk-off self-compensated quasi-collinear CF-OPA geometry adopting three cascaded BBO crystals, which can be easily generalized to other wavelengths or nonlinear crystals. The above nonlinear temporal filter with a CF-OPA scheme has the rarest comprehensive parameters, which can provide excellent seed pulses for PW and 10 PW class femtosecond laser systems.

14.
Opt Express ; 29(21): 32973-32982, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34809118

RESUMO

The effect of surface phonon resonance (SPhR) and long range SPhR (LRSPhR) on the Goos-Hänchen shift (GHS) in the mid-infrared wavelength region are investigated. The GHS is significantly enhanced around the resonant angles of SPhR and LRSPhR with the p-polarized incident light. A highly sensitive refractive index sensor based on the enhanced GHS is proposed. The LRSPhR shows higher GHS and sensitivity than those of SPhR. The GHS and refractive index sensitivity can be further enhanced by engineering the damping rate of the phononic material. These results provide a potential route toward the large GHS and high refractive index sensitivity, thus opening up new opportunities for high sensitivity optical sensors based on GHS at the mid-infrared wavelength range.

17.
Bioengineered ; 12(2): 10945-10958, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34723781

RESUMO

Dysregulated microRNAs (miRNAs) are common in human cancers and are involved in the proliferation, promotion, and metastasis of tumor cells. Therefore, the aim of this study was to evaluate the expression and biological function of miR-889-3p in lung cancer (LC). MiR-889-3p and Homeodomain-interacting protein kinase 1 (HIPK1) expression was detected in human LC tissues and cells. The correlation of miR-889-3p with the clinicopathology of LC patients was observed. After the transfection of miR-889-3p and HIPK1-related plasmids in human LC cell line A549, several studies were employed for detection of cell growth. In addition, the targeting of miR-889-3p with HIPK1 was verified. The results clarified miR-889-3p was down-regulated, while HIPK1 was up-regulated in LC tissues. Elevated miR-889-3p or repressed HIPK1 weakened the viability, epithelial-mesenchymal transition (EMT), invasion, migration of LC cells, whereas strengthened apoptosis. MiR-889-3p targeted HIPK1; MiR-889-3p mediated HIPK1 to affect the proliferation and EMT of LC cells. Therefore, it is concluded that miR-889-3p repressing HIPK1 restrains the proliferation and EMT of LC cells, providing a novel target for LC therapy.

18.
Neoplasia ; 23(12): 1252-1260, 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34775232

RESUMO

T cell based immunotherapies can be applicable to acute myeloid leukemia (AML). Therefore, the selection of optimal T cells, cell manufacturing, and therapeutic T cell engineering are essential for the development of effective adoptive T cell therapies for AML. Autologous tumor-infiltrating lymphocytes (TILs) have been in clinical trials to treat solid malignancies. Herein, we assessed whether TILs can be isolated from the bone marrow (BM) of AML patients, expanded ex vivo and utilized as a novel therapeutic strategy for AML. To this end, firstly we analyzed the immunophenotypes of a series of primary BM samples from AML patients (N = 10) by flow cytometry. We observed a variable amount of CD3+ TILs (range ∼2.3-∼32.6% of mononuclear cells) among BM samples. We then developed a novel protocol that produced a three-log ex vivo expansion of TILs isolated from AML patient BM (N = 10) and peripheral blood (PB) (N = 10), including from patients with a low number of CD3+ T cells, within 3, 4 weeks. Further, we identified previously described naïve T cells (CCR7+CD95-/or CD62L+CD45RA+) in AML BM and PB samples, which seemed to be required for a successful TILs ex vivo expansion. Finally, we showed that the expanded TILs could: (1) cause cytotoxicity to autologous AML blasts ex vivo (90.6% in control without T cell treatment vs. 1.89% in experimental groups with PB derived T cells and 1.77% in experimental groups with BM derived TILs, p < 0.01), (2) be genetically engineered to express CYP27B1 gene, and (3) infiltrate the BM and reside in close proximity to pre-injected autologous AML blasts of engrafted immunodeficiency mice. Altogether, these results provide a rationale for further studies of the therapeutic use of TILs in AML.

19.
J Med Chem ; 64(22): 16687-16702, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34761679

RESUMO

Blockade of immune checkpoint PD-1/PD-L1 has been a promising anticancer strategy; however, clinically available PD-1/PD-L1 small-molecule inhibitors are lacking. In view of the high potency of compound 2 (BMS-1002), structural fine tuning of the methoxy linkage together with diverse modification in the solvent interaction region was conducted. A series of novel derivatives featuring a difluoromethyleneoxy linkage were designed. Compound 43 was identified as the most promising PD-1/PD-L1 inhibitor with an IC50 value of 10.2 nM in the HTRF assay. This compound is capable of promoting CD8+ T cell activation through inhibiting PD-1/PD-L1 cellular signaling. Moreover, in the Hepa1-6 syngeneic mouse model, administration of compound 43 at 1 mg/kg dosage promoted CD8+ T cell activation and delayed the tumor growth with good tolerance. Notably, the tumor in one mouse of the compound 43-treated group was completely regressed. These results indicate that compound 43 is a promising candidate worthy of further investigation.

20.
Sheng Wu Gong Cheng Xue Bao ; 37(11): 4024-4035, 2021 Nov 25.
Artigo em Chinês | MEDLINE | ID: mdl-34841802

RESUMO

Decellularized extracellular matrix (dECM), which contains many proteins and growth factors, can provide three-dimensional scaffolds for cells and regulate cell regeneration. 3D bioprinting can print the combination of dECM and autologous cells layer by layer to construct the tissue structure of carrier cells. In this paper, the preparation methods of tissue and organ dECM bioink from different sources, including decellularization, crosslinking, and the application of dECM bioink in bioprinting are reviewed, with future applications prospected.


Assuntos
Bioimpressão , Engenharia Tecidual , Matriz Extracelular , Impressão Tridimensional , Tecidos Suporte
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...