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1.
Ther Adv Neurol Disord ; 14: 17562864211054952, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34777577

RESUMO

Background: Neurofilament light chain (NfL) and glial fibrilliary acidic protein (GFAP) have been suggested to be biomarkers of the pathophysiological process of neuromyelitis optica spectrum disorders (NMOSD), but the relationship between the plasma levels of these molecules with disease activity and treatment is incompletely understood. Objective: To investigate the treatment effects of disease-modifying drugs on plasma neurofilament light chain (pNfL) and plasma glial fibrillary acidic protein (pGFAP) and explore the predictive value of pNfL and pGFAP in the activity of NMOSD. Methods: pNfL and pGFAP levels were measured using single-molecule arrays in 72 patients with NMOSD and 38 healthy controls (HCs). Patients with NMOSD received tocilizumab (n = 29), rituximab (n = 23), oral prednisone (n = 16), and oral azathioprine or mycophenolate mofetil (n = 4). Results: NMOSD patients had significantly higher pNfL and pGFAP levels than HCs (pNfL, 18.3 (11.2-39.3) versus 11.5 (7.0-23.3) pg/mL; p = 0.001; pGFAP, 149.7 (88.6-406.5) versus 68.7 (59.4-80.8) pg/mL; p < 0.001). Multivariable regression analyses indicated that baseline pNfL concentration was associated with age (p = 0.017), Expanded Disability Status Scale (EDSS) score (p = 0.002), and recent relapses (p < 0.001). Baseline pGFAP concentration was also associated with EDSS (p < 0.001) and recent relapses (p < 0.001). Compared with prednisone, tocilizumab and rituximab significantly reduced pNfL [tocilizumab, exp(ß), 0.65; 95% confidence interval (CI), 0.56-0.75; p < 0.001; rituximab, exp(ß), 0.79; 95% CI = 0.68-0.93; p = 0.005] and pGFAP levels [tocilizumab, exp(ß), 0.64; 95% CI, 0.51-0.80; p < 0.001; rituximab, exp(ß), 0.77; 95% CI, 0.61-0.98; p = 0.041] at the end of the study. The pNfL levels in the tocilizumab and rituximab groups were reduced to those of HCs [tocilizumab, 8.5 (7.06-17.90) pg/mL; p = 0.426; rituximab, 14.0 (9.94-21.80) pg/mL; p = 0.216]. However, the pGFAP levels did not decrease to those of HCs in NMOSD patients at the end of study [tocilizumab, 88.9 (63.4-131.8) pg/mL; p = 0.012; rituximab, 141.7 (90.8-192.7) pg/mL; p < 0.001]. Conclusion: pNfL and pGFAP may serve as biomarkers for NMOSD disease activity and treatment effects.

2.
Gen Physiol Biophys ; 40(5): 351-363, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34602449

RESUMO

Successful implantation requires endometrial receptivity. To investigate the mechanisms of miR-494-3p on endometrial receptivity, GnRHa's superovulation scheme was designed to reduce endometrial receptivity, and the pregnant mice were injected with miR-494-3p antagomir. The regulatory role of miR-494-3p was identified by RT-qPCR, uterine blastocyst count, scanning electron microscopy, hematoxylin-eosin (HE) staining, and Western blot. Results indicated that miR-494-3p antagomir increased uterine blastocysts numbers, promoted the pinocytosis expressions, and increased endometrial thickness. Besides, miR-494-3p antagomir significantly increased leukemia inhibitory factor (LIF), Ang-2 and VEGF protein expressions, and up-regulated p-AKT/AKT and p-mTOR/mTOR protein ratios in endometrium. Luciferase assay confirmed that LIF was a potential target of miR-494-3p. Subsequently, human endometrial epithelial cells (hEECs) were transfected with miR-494-3p inhibitor and PI3K inhibitor (LY294002). The role of miR-494-3p was identified by RT-qPCR, CCK-8 assay, transwell assay and flow cytometry. Results indicated that miR-494-3p inhibitor significantly increased proliferation and invasion, and significantly inhibited apoptosis in hEECs, while LY294002 reversed its biological function. Overall, these results suggested that miR-494-3p is the key regulator of endometrial receptivity in mice, regulating this complex process through the PI3K/AKT/mTOR pathway. Understanding the role of miR-494-3p in endometrial receptivity is of great significance for exploring new targets for the diagnosis and treatment of early pregnancy failure, and improving the success rates of artificial reproduction.


Assuntos
MicroRNAs/genética , Fosfatidilinositol 3-Quinases , Animais , Endométrio , Feminino , Camundongos , Gravidez , Proteínas Proto-Oncogênicas c-akt , Serina-Treonina Quinases TOR
3.
Neurosurgery ; 89(6): 978-986, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34634107

RESUMO

BACKGROUND: Carpal tunnel syndrome (CTS) is a common peripheral entrapment neuropathy. However, CTS-related changes of brain structural covariance and structural covariance networks (SCNs) patterns have not been clearly studied. OBJECTIVE: To explore CTS-related brain changes from perspectives of structural connectivity and SCNs. METHODS: Brain structural magnetic resonance images were acquired from 27 CTS patients and 19 healthy controls (HCs). Structural covariance and SCNs were constructed based on gray matter volume. The global network properties including clustering coefficient (Cp), characteristic path length (Lp), small-worldness index, global efficiency (Eglob), and local efficiency (Eloc) and regional network properties including degree, betweenness centrality (BC), and Eloc of a given node were calculated with graph theoretical analysis. RESULTS: Compared with HCs, the strength of structural connectivity between the dorsal anterior insula and medial prefrontal thalamus decreased (P < .001) in CTS patients. There was no intergroup difference of area under the curve for Cp, Lp¸ Eglob, and Eloc (all P > .05). The real-world SCN of CTS patients showed a small-world topology ranging from 2% to 32%. CTS patients showed lower nodal degrees of the dorsal anterior insula and medial prefrontal thalamus, and higher Eloc of a given node and BC in the lateral occipital cortex (P < .001) and the dorsolateral middle temporal gyrus (P < .001) than HCs, respectively. CONCLUSION: CTS had a profound impact on brain structures from perspectives of structural connectivity and SCNs.

4.
Biomaterials ; 278: 121169, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34626937

RESUMO

In the early stage of osteoarthritis (OA), cartilage degradation in the surface region leads to superficial cartilage defect. However, enhancing the regeneration of cartilage defect remains a great challenge for existing hydrogel technology because of the weak adhesion to wet tissue. In the present study, an injectable mussel-inspired highly adhesive hydrogel with exosomes was investigated for endogenous cell recruitment and cartilage defect regeneration. The hydrogel with high bonding strength to the wet surface was prepared using a crosslinked network of alginate-dopamine, chondroitin sulfate, and regenerated silk fibroin (AD/CS/RSF). Compared with commercial enbucrilate tissue adhesive, the AD/CS/RSF hydrogel provided a comparative lap shear strength of 120 kPa, with a similar gelation time and a higher capacity for maintaining adhesive strength. The AD/CS/RSF/EXO hydrogel with encapsulated exosomes recruited BMSCs migration and inflation, promoted BMSCs proliferation and differentiation. Most importantly, the AD/CS/RSF/EXO hydrogel accelerated cartilage defect regeneration in situ, and extracellular matrix remodeling after injection in rat patellar grooves. The exosomes released by the hydrogels could recruit BMSCs into the hydrogel and neo-cartilage via the chemokine signaling pathway. Our findings reveal an injectable and adhesive hydrogel for superficial cartilage regeneration, which is a promising approach for minimally treating cartilage defect with arthroscopic assistance.


Assuntos
Exossomos , Hidrogéis , Adesivos , Animais , Cartilagem , Ratos , Regeneração , Engenharia Tecidual , Tecidos Suporte
5.
World J Stem Cells ; 13(7): 753-775, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34367476

RESUMO

Tendon-bone insertion injuries such as rotator cuff and anterior cruciate ligament injuries are currently highly common and severe. The key method of treating this kind of injury is the reconstruction operation. The success of this reconstructive process depends on the ability of the graft to incorporate into the bone. Recently, there has been substantial discussion about how to enhance the integration of tendon and bone through biological methods. Stem cells like bone marrow mesenchymal stem cells (MSCs), tendon stem/progenitor cells, synovium-derived MSCs, adipose-derived stem cells, or periosteum-derived periosteal stem cells can self-regenerate and potentially differentiate into different cell types, which have been widely used in tissue repair and regeneration. Thus, we concentrate in this review on the current circumstances of tendon-bone healing using stem cell therapy.

6.
Artigo em Inglês | MEDLINE | ID: mdl-34435457

RESUMO

BACKGROUND: Sarcopenia widely exists in elderly people and triggers numerous age-related events. The essential pathologic change lies in the increased intramuscular adipose tissue after aging with no exception to non-obese objects. Pim1 appears to be associated with adipogenic differentiation in recent studies, inspiring us to explore whether it regulates adipogenesis in aging muscles and affects sarcopenia. METHODS: Wild-type and Pim1 knockout C57/BL6J mice were randomized into young and old groups. Histo-pathological and molecular biological methods were applied to assess the intramuscular adipose tissue content, the atrophy and regeneration, and the expressions of Pim1 and adipogenic transcription factors. PDGFRα+ mesenchymal progenitors were separated and their replicative aging model were established. Different time of adipogenic induction and different amounts of Pim1 inhibitor were applied, after which the adipogenic potency were evaluated. The expressions of Pim1 and adipogenic transcription factors were measured through western blotting. RESULTS: The aging mice demonstrated decreased forelimb grip strength (P = 0.0003), hanging impulse (P < 0.0001), exhaustive running time (P < 0.0001), tetanic force (P = 0.0298), lean mass (P = 0.0008), and percentage of gastrocnemius weight in body weight (P < 0.0001), which were improved by Pim1 knockout (P = 0.0015, P = 0.0222, P < 0.0001, P = 0.0444, P = 0.0004, and P = 0.0003, respectively). To elucidate the mechanisms, analyses showed that Pim1 knockout decreased the fat mass (P = 0.0005) and reduced the intramuscular adipose tissue content (P = 0.0008) by inhibiting the C/EBPδ pathway (P = 0.0067) in aging mice, resulting in increased cross-sectional area of all and fast muscle fibres (P = 0.0017 and 0.0024 respectively), decreased levels of MuRF 1 and atrogin 1 (P = 0.0001 and 0.0329 respectively), and decreased content of Pax7 at the basal state (P = 0.0055). In vitro, senescent PDGFRα+ mesenchymal progenitors showed significantly increased the intracellular adipose tissue content (OD510) compared with young cells after 6 days of adipogenic induction (P < 0.0001). The Pim1 expression was elevated during adipogenic differentiation, and Pim1 inhibition significantly reduced the OD510 in senescent cells (P = 0.0040) by inhibiting the C/EBPδ pathway (P = 0.0047). CONCLUSIONS: Pim1 knockout exerted protective effects in sarcopenia by inhibiting the adipogenic differentiation of PDGFRα+ mesenchymal progenitors induced by C/EBPδ activation and thus reducing the intramuscular adipose tissue content in aging mice. These results provide a potential target for the treatment of sarcopenia.

7.
Fitoterapia ; 153: 104989, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34252513

RESUMO

Ten new nortriterpenes, euphorbiumrins A-J (1-10), together with three known analogues (11-13) were isolated from the latex of Euphorbia resinifera. Their structures were established on the basis of extensive spectroscopic analyses (IR, UV, HRESIMS, 1D and 2D NMR). Their inhibitions on tomato yellow leaf curl virus (TYLCV) were evaluated and compound 5 exhibited significant anti-TYLCV activity with an inhibition rate of 71.7% at concentration of 40 µg/mL.


Assuntos
Begomovirus/efeitos dos fármacos , Euphorbia/química , Doenças das Plantas/prevenção & controle , Triterpenos/farmacologia , China , Látex/química , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Doenças das Plantas/virologia , Tabaco/virologia , Triterpenos/isolamento & purificação
8.
Mol Med Rep ; 24(1)2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34080650

RESUMO

Diet and exercise are the most effective approaches used to induce weight loss. D­psicose is a low­calorie sweetener that has been shown to reduce weight in obese individuals. However, the effect of D­psicose on muscle cells under oxidative stress, which is produced during exercise, requires further investigation. The present study aimed to determine the effects of D­psicose on C2C12 myogenic cells in vitro. Hydrogen peroxide (H2O2) was used to stimulate the generation of intracellular reactive oxygen species (ROS) in muscle cells to mimic exercise conditions. Cell viability was analyzed using a MTT assay and flow cytometry was used to analyze the levels of apoptosis, mitochondrial membrane potential (MMP), the generation of ROS and the cell cycle distribution following treatment. Furthermore, protein expression levels were analyzed using western blotting and cell proliferation was determined using a colony formation assay. The results of the present study revealed that D­psicose alone exerted no toxicity on C2C12 mouse myogenic cells. However, in the presence of low­dose (100 µM) H2O2­induced ROS, D­psicose induced C2C12 cell injury and significantly decreased C2C12 cell viability in a dose­dependent manner. In addition, the levels of apoptosis and the generation of ROS increased, while the MMP decreased. MAPK family molecules were also activated in a dose­dependent manner following treatment. Notably, the combined treatment induced G2/M phase arrest and reduced the proliferation of C2C12 cells. In conclusion, the findings of the present study suggested that D­psicose may induce toxic effects on muscle cells in a simulated exercise situation by increasing ROS levels, activating the MAPK signaling pathway and disrupting the MMP.


Assuntos
Apoptose/efeitos dos fármacos , Frutose/farmacologia , Peróxido de Hidrogênio/efeitos adversos , Proteínas de Membrana/metabolismo , Desenvolvimento Muscular/efeitos dos fármacos , Músculo Esquelético/metabolismo , Edulcorantes/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Frutose/química , Pontos de Checagem da Fase M do Ciclo Celular , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas de Membrana/genética , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
9.
Brain Res ; 1767: 147558, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34116054

RESUMO

Functional and structural brain alterations have been noted in carpal tunnel syndrome (CTS), the most common entrapment peripheral neuropathy. Previous studies were mainly focused on somatosensory cortices. However, the changes of white matter diffusion properties in nonsensorimotor cortices remain uninvestigated. We utilized a modified tract-based spatial statistics (TBSS) pipeline to explore CTS-related white matter plasticity, omitting the skeletonization step and registering diffusion tensor imaging (DTI) data to a study-specific, high resolution T1 template by an optimized registration method. The modified TBSS was demonstrated to be more sensitive to detect changes in white matter integrity than the standard TBSS approach. In this study, 25 moderate/severe CTS patients and 17 age- and sex-matched healthy controls (HC) were evaluated with DTI. Fractional anisotropy (FA) and radial diffusivity (RD) were calculated for group comparison. And the relationship between diffusion parameters and clinical assessments was also analyzed. Comparing with the healthy controls, CTS patients showed significantly increased FA and decreased RD in areas of multisensory integration and motor control involving the central opercular cortex and supplementary motor area (SMA) of the dominant hemisphere. Moreover, altered diffusion parameters in the central opercular cortex of the dominant hemisphere were significantly correlated with Boston Carpal Tunnel Questionnaire (BCTQ) scores. It is considered to be a form of maladaptive neuroplastic response to CTS-associated afference and motor control deficits. Such insight may be helpful in developing new strategies for the treatment of CTS.

10.
Chemistry ; 27(42): 10957-10965, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-33884685

RESUMO

Porous materials have been investigated as efficient photochromic platforms for detecting hazardous radiation, while the utilization of hydrogen bonded organic frameworks (HOFs) in this field has remained intact. Herein, two HOFs were synthesized through self-assembly of tetratopic viologen ligand and formic acid (PFC-25, PFC-26), as a new class of "all-organic" radiochromic smart material, opening a gate for HOFs in this field. PFC-26 is active upon both X-ray and UV irradiation, while PFC-25 is only active upon X-ray irradiation. The same building block yet different radiochromic behaviors of PFC-25 and PFC-26 allow us to gain a deep mechanistic understanding of the factors that control the detection specificity. Theoretical and experimental studies reveal that the degree of π-conjugation of viologen ligand is highly related to the threshold energy of triggering a charge transfer, therefore being a vital factor for the particularity of radiochromic materials. Thanks to its convenient processibility, nanoparticle size, and UV silence, PFC-25 can be further fabricated into a portable naked-eye sensor for X-ray detection, which shows obvious color change with the merits of high transmittance contrast, good sensitivity (reproducible dose threshold of 3.5 Gy), and excellent stability. The work exhibits the promising practical potentials of HOF materials in photochromic technology.


Assuntos
Hidrogênio , Viologênios , Ligação de Hidrogênio , Raios X
11.
Apoptosis ; 26(3-4): 219-231, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33738673

RESUMO

Acute myeloid leukemia (AML) is a malignant cancer of the hematopoietic system. Although the effectiveness of arsenic compounds has been recognized and applied clinically, some patients are still found resistant to this chemotherapy. In this study, we investigated that a synthetic thyroid hormone analog (TA), 2-iodo-4-nitro-1-(o-tolyloxy) benzene, had a strong apoptosis effect on U937 cells. U937 cells were treated with TA, and examinted the generation of reactive oxygen species (ROS), dysfunction of mitochondria, expression of pro-apoptosis and anti-apoptosis, and cleavage of caspase-3 and Poly (ADP-ribose) polymerase (PARP). Further, it is also evaluated that insight molecular mechanism and signaling pathways involved in the study. It is found that TA significantly induced apoptosis in U937 cells through production of ROS, dysfunction of mitochondria, and activation of caspase cascade. It was also observed that MAPK signaling pathway including ERK, JNK, and P38 signals are involved in the induction of apoptosis. Moreover, marked activation of autophagy and ER stress markers such as LC3, P62, Beclin1 and GRP78, CHOP were observed, respectively. Pretreatment with ER stress inhibitor tauroursodeoxycholic acid (TUDCA) and autophagy inhibitor 3-Methyladenine (3-MA) have successfully attenuated and aggravated TA-induced apoptosis, respectively. We further confirmed the active involvement of ER stress and autophagy signals. In conclusion, TA induced apoptosis through ER stress and activation of autophagy, and the latter is not conducive to TA-induced cell death. Our results may provide a new insight into the strategic development of novel therapy for the treatment of AML.


Assuntos
Apoptose/efeitos dos fármacos , Iodobenzoatos/farmacologia , Leucemia Mieloide/tratamento farmacológico , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Células U937
12.
Front Cell Infect Microbiol ; 11: 643092, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33768014

RESUMO

Rheumatic heart disease refers to the long-term damage of heart valves and results from an autoimmune response to group A Streptococcus infection. This study aimed to analyze the microbiota composition of patients with rheumatic heart disease and explore potential function of microbiota in this disease. First, we revealed significant alterations of microbiota in feces, subgingival plaques, and saliva of the patients compared to control subjects using 16S rRNA gene sequencing. Significantly different microbial diversity was observed in all three types of samples between the patients and control subjects. In the gut, the patients possessed higher levels of genera including Bifidobacterium and Eubacterium, and lower levels of genera including Lachnospira, Bacteroides, and Faecalibacterium. Coprococcus was identified as a super-generalist in fecal samples of the patients. Significant alterations were also observed in microbiota of subgingival plaques and saliva of the patients compared to control subjects. Second, we analyzed microbiota in mitral valves of the patients and identified microbes that could potentially transmit from the gut or oral cavity to heart valves, including Streptococcus. Third, we further analyzed the data using random forest model and demonstrated that microbiota in the gut, subgingival plaque or saliva could distinguish the patients from control subjects. Finally, we identified gut/oral microbes that significantly correlated with clinical indices of rheumatic heart disease. In conclusion, patients with rheumatic heart disease manifested important alterations in microbiota that might distinguish the patients from control subjects and correlated with severity of this disease.


Assuntos
Microbioma Gastrointestinal , Microbiota , Cardiopatia Reumática , Fezes , Humanos , Valva Mitral , Boca , RNA Ribossômico 16S
13.
Neural Plast ; 2021: 8815144, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33603780

RESUMO

Purpose: This study is aimed at investigating brain structural changes and structural network properties in complete spinal cord injury (SCI) patients, as well as their relationship with clinical variables. Materials and Methods: Structural MRI of brain was acquired in 24 complete thoracic SCI patients (38.50 ± 11.19 years, 22 males) within the first postinjury year, while 26 age- and gender-matched healthy participants (38.38 ± 10.63 years, 24 males) were enrolled as control. The voxel-based morphometry (VBM) approach and graph theoretical network analysis based on cross-subject grey matter volume- (GMV-) based structural covariance networks (SCNs) were conducted to investigate the impact of SCI on brain structure. Partial correlation analysis was performed to explore the relationship between the GMV of structurally changed brain regions and SCI patients' clinical variables, including injury duration, injury level, Visual Analog Scale (VAS), American Spinal Injury Association Impairment Scale (AIS), International Classification of Functioning, Disability and Health (ICF) scale, Self-rating Depression Scale (SDS), and Self-rating Anxiety Scale (SAS), after removing the effects of age and gender. Results: Compared with healthy controls, SCI patients showed higher SDS score (t = 4.392 and p < 0.001). In the VBM analysis, significant GMV reduction was found in the left middle frontal cortex, right superior orbital frontal cortex (OFC), and left inferior OFC. No significant difference was found in global network properties between SCI patients and healthy controls. In the regional network properties, significantly higher betweenness centrality (BC) was noted in the right anterior cingulum cortex (ACC) and left inferior OFC and higher nodal degree and efficiency in bilateral middle OFCs, while decreased BC was noted in the right putamen in SCI patients. Only negative correlation was found between GMV of right middle OFC and SDS score in SCI patients (r = -0.503 and p = 0.017), while no significant correlation between other abnormal brain regions and any of the clinical variables (all p > 0.05). Conclusions: SCI patients would experience depressive and/or anxious feelings at the early stage. Their GMV reduction mainly involved psychology-cognition related rather than sensorimotor brain regions. The efficiency of regional information transmission in psychology-cognition regions increased. Greater GMV reduction in psychology region was related with more severe depressive feelings. Therefore, early neuropsychological intervention is suggested to prevent psychological and cognitive dysfunction as well as irreversible brain structure damage.


Assuntos
Encéfalo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Traumatismos da Medula Espinal/diagnóstico por imagem , Adulto , Encéfalo/fisiopatologia , Feminino , Substância Cinzenta/fisiopatologia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Medula Espinal , Traumatismos da Medula Espinal/fisiopatologia , Adulto Jovem
14.
Orthop Surg ; 13(1): 126-133, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33295133

RESUMO

OBJECTIVE: To identify the efficacy and safety of multiple doses of intravenous tranexamic acid (IV-TXA) following primary total knee arthroplasty (TKA) with a tourniquet. METHODS: This is a single-blind randomized controlled study that recruited osteoarthritis patients who had undergone primary unilateral TKA from May 2019 to May 2020 at our medical center. A total of 300 patients were randomly divided into three groups to receive: one dose (1 g) of IV-TXA before skin incision combined with one dose (1.5 g) of intra-articular tranexamic acid(IA-TXA) followed by a single dose of IV-TXA (1 g) for 3 h (group A); two doses of IV-TXA (1 g) for 3 and 6 h (group B); or three doses of IV-TXA (1 g) for 3, 6, and 12 h (group C) postoperatively. TKA with a tourniquet was performed by the same surgical team. The primary outcomes were total blood cell loss (TBL), hidden blood loss (HBL), maximum hemoglobin (Hb) drop, and transfusion rate. Secondary outcomes were levels of C-reactive protein (CRP) and D-dimer, and the incidence of postoperative complications. One-way analysis of variance, subgroup analysis, and multivariate correlation analysis were used to calculate the differences among the three groups. RESULTS: The study included 56 male and 244 female patients aged 60-80 years. The mean TBL, the mean HBL, and the maximum Hb drop in group C (471.2 ± 190.6 mL, 428.4 ± 190.3 mL, and 21.2 ± 3.8 g/L, respectively) were significantly lower than those in groups B (563.4 ± 224.6 mL, P = 0.030; 519.9 ± 226.4 mL, P = 0.033; and 23.2 ± 4.1 g/L, P = 0.001, respectively), and A (651.6 ± 254.1 mL, P < 0.001; 607.1 ± 254.3 mL, P < 0.001; and 25.1 ± 4.3 g/L, P < 0.001, respectively). No transfusions were required. The postoperative acute inflammatory reaction was less problematic for patients in Group C, and the incidence of thromboembolic events was similar among the groups (P > 0.05). In addition, there were positive correlations between the HBL and the tourniquet inflation time (r = 0.844, P < 0.001). Similarly, the level of CRP on POD1 (r = 0.393, P < 0.001) and POD3 (r = 0.149, P = 0.010), and the level of D-dimer on POD1 (r = 0.382, P < 0.001) were positively correlated with the HBL. CONCLUSION: Three doses of postoperative IV-TXA decreased blood loss and diminished the postoperative inflammatory and fibrinolytic response more than a single dose or two doses in elderly patients following TKA without increasing the incidence of adverse events.

15.
Fitoterapia ; 147: 104731, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32979466

RESUMO

Two new steroidal alkaloids (1-2), together with seven known related steroidal alkaloids (3-9), were isolated from the rhizomes of Veratrum nigrum L. Their structures were elucidated by extensive spectroscopic analysis, and by comparison with literature data. Compound 1 possessed a rare 1, 3-oxazolidine unit within varazine-type alkaloids, and 2 was a 9-hydroxy-4-one derivative of 3-veratroylgermine. All isolates were evaluated inhibit tomato yellow leaf curl virus (TYLCV) activity. Compounds 5 and 7 (40 µg/mL) showed a significant anti-TYLCV activity in the host Nicotiana benthamiana with inhibition rates 74.6% and 63.4%, respectively, which are higher than that of the positive control ningnanmycin (51.4%).


Assuntos
Alcaloides/farmacologia , Begomovirus/efeitos dos fármacos , Doenças das Plantas/prevenção & controle , Esteroides/farmacologia , Veratrum/química , Alcaloides/isolamento & purificação , China , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Doenças das Plantas/virologia , Rizoma/química , Esteroides/isolamento & purificação , Tabaco/virologia
16.
J Int Med Res ; 48(8): 300060520939672, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32865090

RESUMO

OBJECTIVE: We investigated physical deviation and precocious puberty among school-aged children in Leshan City, to provide a theoretical basis for the management of precocious puberty in children. METHODS: We selected 12 primary schools of Leshan City using a cluster random sampling method and conducted physical examinations among healthy students aged 4 12 years. A total of 11,000 students were recruited (5502 boys and 5498 girls). We measured body mass index (BMI), and participants were tested for precocious puberty according to the Tanner stages and standard maps. Nutritional status was also evaluated. RESULTS: Obese and overweight children accounted for a high proportion of participants; the prevalence of underweight was the lowest. The prevalence of obesity among boys was higher than that in girls. Precocious puberty was mainly observed in girls, particularly those age 7 years old. The prevalence of precocious puberty among overweight and obese children was higher than that in children with normal weight. CONCLUSION: We identified a significant sex difference in precocious puberty among children in Leshan City. Overweight and obesity may be associated with precocious puberty.


Assuntos
Puberdade Precoce , Índice de Massa Corporal , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Sobrepeso/epidemiologia , Prevalência , Puberdade Precoce/epidemiologia , Instituições Acadêmicas
17.
Phys Chem Chem Phys ; 22(24): 13603-13612, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32515446

RESUMO

Isoprene is the most abundant alkene in the atmosphere. Ozonolysis of isoprene produces three very reactive carbonyl oxides (Criegee intermediates), including formaldehyde oxide, methyl vinyl ketone oxide (MVKO, CH3(C2H3)COO), and methacrolein oxide. The latter two Criegee intermediates are resonance-stabilized due to the vinyl group. Recently, the electronic spectrum of thermalized MVKO has been reported [Caravan, et al., Proc. Natl. Acad. Sci. U. S. A., 2020, 117, 9733]. In this work, we utilized this strong UV/visible absorption to investigate the reaction kinetics of MVKO with SO2 under a wide pressure range of 4 to 700 Torr. We followed a new method [Barber, et al., J. Am. Chem. Soc., 2018, 140, 10866], in which MVKO is produced through the reaction of a resonance-stabilized iodoalkene radical with O2. The experimental data are consistent with a kinetic model that the reaction goes through an adduct of CH3(C2H3)CIOO, similar to the cases of H/alkyl substituted Criegee intermediates. However, different from the H/alkyl adducts, which are stable over the time scales of typical kinetic experiments, this vinyl adduct CH3(C2H3)CIOO is less stable and decomposes to MVKO + I at a time scale of 10-3 s (faster at higher temperature), consistent with the results of quantum chemistry calculations and the fact that the resonance stabilization is disrupted at the adduct structure. The adduct decomposition is the major pathway that forms MVKO for pressures higher than 50 Torr. In addition, temperature dependence has been investigated for 278-319 K. The experimental activation energy of the adduct decomposition was measured to be 12.7 ± 0.3 kcal mol-1, consistent with the calculated dissociation energy of the adduct to MVKO + I (14 kcal mol-1). Furthermore, the temperature dependent rate coefficient of MVKO + SO2 reaction has been measured to be kSO2 = (4.0 ± 0.6) × 10-11 cm3 s-1 at 4-700 Torr and 298 K with a negative activation energy of -3.7 ± 0.4 kcal mol-1.

18.
Life Sci ; 256: 117923, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32522567

RESUMO

AIMS: Liver kinase B1 (LKB1) deficiency is associated with reduced expression of programmed death ligand 1 (PD-L1) and inferior clinical outcomes of PD-1/PD-L1 blockade in non-small cell lung cancer (NSCLC). This study aimed to investigate the mechanism by which LKB1 regulates PD-L1 expression and its role in programmed death 1 (PD-1) blockade therapy in NSCLC. MAIN METHODS: The impact of LKB1 on PD-L1 was assessed by western blot, qRT-PCR and immunohistochemistry in NSCLC. Activators/inhibitors of AMPK and NRF2 were applied to explore the mechanisms underlying the regulation of PD-L1 by LKB1. Efficiency of combined application of metformin and PD-1 blockade was evaluated in immunocompetent C57BL/6 mice. KEY FINDINGS: A remarkable positive correlation between LKB1 and PD-L1 expression was demonstrated in NSCLC tissues. Knockdown of LKB1 decreased PD-L1 in TC-1 cells, whereas overexpression of LKB1 increased PD-L1 in A549 cells. We further characterized that AMPK mediated the upregulation of PD-L1 by LKB1. Inhibition of AMPK or NRF2 markedly reduced PD-L1 in LKB1-intact NSCLC cells. In contrast, activation of AMPK or NRF2 reversed PD-L1 expression in LKB1-deficient NSCLC cells. Combined administration of metformin and anti-PD-1 antibody efficiently inhibited the growth of LKB1-intact tumors, whereas no obvious suppression was observed in LKB1-deficient tumors. SIGNIFICANCE: These findings demonstrated that LKB1 upregulates PD-L1 expression in NSCLC by activating the AMPK and KEAP1/NRF2 signaling. Activation of LKB1-AMPK with metformin improves the therapeutic effect of PD-1 blockade in NSCLC with wild-type LKB1.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , Metformina/farmacologia , Receptor de Morte Celular Programada 1/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Células A549 , Animais , Anticorpos Monoclonais Humanizados/metabolismo , Antineoplásicos/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Metformina/metabolismo , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Transdução de Sinais , Ativação Transcricional , Regulação para Cima
19.
Proc Natl Acad Sci U S A ; 117(18): 9733-9740, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32321826

RESUMO

Isoprene has the highest emission into Earth's atmosphere of any nonmethane hydrocarbon. Atmospheric processing of alkenes, including isoprene, via ozonolysis leads to the formation of zwitterionic reactive intermediates, known as Criegee intermediates (CIs). Direct studies have revealed that reactions involving simple CIs can significantly impact the tropospheric oxidizing capacity, enhance particulate formation, and degrade local air quality. Methyl vinyl ketone oxide (MVK-oxide) is a four-carbon, asymmetric, resonance-stabilized CI, produced with 21 to 23% yield from isoprene ozonolysis, yet its reactivity has not been directly studied. We present direct kinetic measurements of MVK-oxide reactions with key atmospheric species using absorption spectroscopy. Direct UV-Vis absorption spectra from two independent flow cell experiments overlap with the molecular beam UV-Vis-depletion spectra reported recently [M. F. Vansco, B. Marchetti, M. I. Lester, J. Chem. Phys. 149, 44309 (2018)] but suggest different conformer distributions under jet-cooled and thermal conditions. Comparison of the experimental lifetime herein with theory indicates only the syn-conformers are observed; anti-conformers are calculated to be removed much more rapidly via unimolecular decay. We observe experimentally and predict theoretically fast reaction of syn-MVK-oxide with SO2 and formic acid, similar to smaller alkyl-substituted CIs, and by contrast, slow removal in the presence of water. We determine products through complementary multiplexed photoionization mass spectrometry, observing SO3 and identifying organic hydroperoxide formation from reaction with SO2 and formic acid, respectively. The tropospheric implications of these reactions are evaluated using a global chemistry and transport model.

20.
Zhongguo Zhong Yao Za Zhi ; 45(4): 955-960, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32237499

RESUMO

The standard sample of natural products is an essential standard reference to determine the quality of the product in the quality control of natural products. To develop a certified reference material(CRM) of swertioside according to the Work Guideline for Reference Materials(3): Reference Material-General Principles and Statistical Method for Certification(GB/T 15000.3-2008), swertioside was purified from whole plant of Swertia mussotii by extraction, isolation and Prep-HPLC to obtain certified reference material of swertioside. The structure of swertioside was identified by IR, UV, high-resolution MS, NMR. Thin layer chromatography, optical rotation, elemental analysis and melting point was carried out for the identification. The purity of the prepared sample was tested from different chromatographic elution conditions, thin layer chromatography and HPLC-MS. Swertioside was divided into 140 bottles, with 10 mg per bottle after homogeneity test, stability test and quantitative analysis. This CRM is 7-O-[α-L-rhamnopyranosyl-(1→2)-ß-D-xylopyranosyl]; the homogeneity of the 95% confidence interval was good; the certified purity value was 98.66%, with a relative expanded uncertainty of 0.38%; the storage period was 36 months at 0-8 ℃. Therefore, the CRM of sakuranetin reached the technical requirements of CRM, and was accepted by SAC. Swertioside is successfully developed and can be used for determining content, evaluating test methods, detecting relevant products and controlling quality.


Assuntos
Compostos Fitoquímicos/normas , Swertia/química , Certificação , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Padrões de Referência
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