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1.
Dis Markers ; 2021: 8800358, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34512816

RESUMO

Background: Renal cell carcinoma (RCC) is one of the most common aggressive malignant tumors in the urinary system, among which the clear cell renal cell carcinoma (ccRCC) is the most common subtype. The immune-related long noncoding ribonucleic acids (irlncRNAs) which are abundant in immune cells and immune microenvironment (IME) have potential significance in evaluating the prognosis and effects of immunotherapy. The signature based on irlncRNA pairs and independent of the exact expression level seems to have a latent predictive significance for the prognosis of patients with malignant tumors but has not been applied in ccRCC yet. Method: In this article, we retrieved The Cancer Genome Atlas (TCGA) database for the transcriptome profiling data of the ccRCC and performed coexpression analysis between known immune-related genes (ir-genes) and lncRNAs to find differently expressed irlncRNA (DEirlncRNA). Then, we adopted a single-factor test and a modified LASSO regression analysis to screen out ideal DEirlncRNAs and constructed a Cox proportional hazard model. We have sifted 28 DEirlncRNA pairs, 12 of which were included in this model. Next, we compared the area under the curve (AUC), found the cutoff point by using the Akaike information criterion (AIC) value, and distinguished the patients with ccRCC into a high-risk group and a low-risk group using this value. Finally, we tested this model by investigating the relationship between risk score and survival, clinical pathological characteristics, cells in tumor immune microenvironment, chemotherapy, and targeted checkpoint biomarkers. Results: A novel immune-related lncRNA pair signature consisting of 12 DEirlncRNA pairs was successfully constructed and tightly associated with overall survival, clinical pathological characteristics, cells in tumor immune microenvironment, and reactiveness to immunotherapy and chemotherapy in patients with ccRCC. Besides, the efficacy of this signature was verified in some commonly used clinicopathological subgroups and could serve as an independent prognostic factor in patients with ccRCC. Conclusions: This signature was proven to have a potential predictive significance for the prognosis of patients with ccRCC and the efficacy of immunotherapy.

2.
BMC Neurol ; 21(1): 348, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34507542

RESUMO

BACKGROUND: Central nervous system overlapping autoimmune syndromes are uncommon, especially with the coexistence of MOG-IgG and GFAP-IgG. CASE PRESENTATION: A 23-year-old woman presented with transient convulsions, a loss of consciousness, persistent fever, headache, and vomiting. Cerebrospinal fluid (CSF) analysis revealed elevated cellularity, and magnetic resonance imaging (MRI) showed diffuse leptomeningeal enhancement. She had fever and headache with antiviral and antibiotic treatment for 2 weeks, and she had empirical anti-tuberculosis treatment and oral prednisolone therapy. She was followed for 3 months after presentation with improved symptoms and normal CSF analysis. A 3-month follow-up MRI showed asymmetric lesions in the cerebellum, corona radiata, and white matter with enhancement. The anti-tuberculosis treatment was continued, and steroid therapy was discontinued. After she stopped taking prednisolone, an interrupted headache gradually appeared. MRI at 4 months after presentation revealed a partial reduction in lesions but enlarged areas in the left cerebellum and right parietal white matter and a new lesion in the region of the right ependyma with linear enhancement. Her CSF was positive for anti-myelin oligodendrocyte glycoprotein (MOG) and anti-glial fibrillary acidic protein (GFAP) antibodies using a transfected cell-based assay. She was diagnosed with overlapping syndrome of MOG­IgG­associated disease and GFAP astrocytopathy. She received steroid pulse therapy (methylprednisolone, 1 g for 5 days), followed by a gradual tapering of oral prednisolone and the addition of an immunosuppressant (tacrolimus, 3 mg per day). Six months after the initial presentation, she had no symptoms. An MRI showed that the lesions had diminished, and no enhancement was found. CONCLUSIONS: We report a case that was positive for double antibodies, which was initially misdiagnosed as infectious meningoencephalitis. This case broadens the clinical and phenotypic presentation of the overlapping syndrome spectrum.

3.
Head Neck ; 2021 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-34510610

RESUMO

BACKGROUND: To describe the indications, technique, and our experience in the application of the transverse cervical artery anterior perforator flap (ap-TCAF) for reconstruction of head and neck oncological defects. METHODS: From September 2016 to September 2019, 11 patients underwent surgical treatment for head neck squamous cell carcinoma and were subsequently reconstructed with ap-TCAFs. The clinical details were recorded, and the postoperative appearance and function were analyzed. RESULTS: The ap-TCAF was used to reconstruct intraoral defects in eight patients and to repair an oropharyngeal defect in one patient. In two remaining patients, the ap-TCAF was divided into two to restore defects with both an intraoral and extraoral component. The flap size ranged from 6 × 4 cm to 15 × 9 cm. All flaps healed uneventfully. There was no delayed wound healing or dysfunction at the donor site. CONCLUSIONS: The ap-TCAF is reliable with characteristics making it useful for head and neck oncological reconstruction, especially in male patients.

4.
Zhongguo Zhong Yao Za Zhi ; 46(16): 4175-4186, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34467730

RESUMO

Excitatory toxicity(ET) is an important factor of neuropathic pain(NPP) induced by central sensitization(CS), and the association of pannexin-1(Panx1)-Src-N-methyl-D-aspartate receptor subunit 2 B(NMDAR-2 B) is an important new pathway for ET to initiate CS. The present study confirmed whether the central analgesic effect of Chuanxiong Rhizoma extract(CRE) was achieved through the synchronous regulation of the brain and spinal pathways of Panx1-Src-NMDAR-2 B. In this study, dynamic and simulta-neo-us microdialysis of the brain and spinal cord in vivo combined with behavioristics, high performance liquid chromatography(HPLC)-fluorescence detection, microdialysis analysis(ISCUS~(flex)), ultrasensitive multifactorial electrochemiluminescence immunoassay, ELISA, and Western blot was employed to investigate the protein expression of NMDAR-2 B, Src, and Panx1, extracellular excitatory amino acids, cytokines, energy metabolites, and substance P in spinal dorsal horn(SDH) and anterior cingulate cortex(ACC) after CRE intervention with the rat model of spared sciatic nerve injury(SNI) as the experimental tool. Compared with the sham group, the SNI group exhibited diminished mechanical withdrawal threshold(MWT)(P<0.01), increased cold spray scores(P<0.01), glutamate(Glu), D-serine(D-Ser), and glycine(Gly) in extracellular fluids of ACC, and Glu, D-Ser, interleukin-1ß(IL-1ß), and lactic acid(Lac) in extracellular fluids of SDH(P<0.05), dwindled tumor necrosis factor(TNF-α)(P<0.05), and elevated protein levels of NMDAR-2 B, Src, and Panx1 in ACC(P<0.05). Compared with the SNI model rats, high-and medium-dose CRE(CRE-H/M) could potentiate the analgesic activity as revealed by the MWT test(P<0.05) and CRE-M enabled the decrease in cold spray scores(P<0.05). CRE-H/M could inhibit the levels of Glu, D-Ser and Gly in the extracellular fluids of ACC(P<0.05), and the levels of Glu in the extracellular fluids of SDH(P<0.05) in SNI rats. CRE-M significantly increased the levels of glucose(Gluc), Lac, interferon-gamma(IFN-γ), keratinocyte chemoattractant/human growth-regulated oncogenes(KC/GRO), and IL-4 in extracellular fluids of SDH in SNI rats(P<0.05). CRE-H/M/L could also inhibit the levels of NMDAR-2 B, Src and Panx1 in ACC and SDH in SNI rats(P<0.05). The central analgesic effect of CRE is presumedly related to the inhibited release of excitatory amino acid transmitters(Glu, D-Ser and Gly) in ACC and SDH of SNI rats, decreased protein expression of NMDAR-2 B, Src and Panx1 in the two regions, and the regulation of the Panx1-Src-NMDAR-2 B pathway in the spinal cord and brain. The above findings partially clarified the scientific basis of clinical analgesic effect of Chuanxiong Rhizoma.


Assuntos
Neuralgia , Receptores de N-Metil-D-Aspartato , Animais , Sensibilização do Sistema Nervoso Central , Neuralgia/tratamento farmacológico , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/genética , Receptores de N-Metil-D-Aspartato/metabolismo , Transdução de Sinais , Medula Espinal/metabolismo
5.
Medicine (Baltimore) ; 100(35): e27087, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34477143

RESUMO

BACKGROUND: Diabetic nephropathy (DN) is one of the most serious complications in the development of diabetes mellitus, which has become the main cause of end-stage renal disease and one of the main causes of death in diabetic patients. With the prevalence of diabetes, the number of patients at risk for developing DN is increasing, with 20-40 percent of all patients with diabetes at risk for developing DN. Acupuncture and Chinese herbal medicine treatments are often combined to treat DN; however, there has been no meta-analysis on their synergistic effects. Therefore, we aimed to perform a systematic review and meta-analysis to estimate the effectiveness of acupuncture combined with Chinese herbal medicine for DN treatment. METHODS: Nine electronic databases were retrieved for this study. The English databases mainly retrieved PubMed, Web of Science, Embase, AMED, and the Cochrane Library, while the CNKI, VIP, CBM, and Wanfang databases were used to retrieve the Chinese literature. There is no definite time limit for the retrieval literature, and the languages are limited to Chinese and English. We will consider articles published between database initiation and August 2021. We used Review Manager 5.4, provided by the Cochrane Collaborative Network for statistical analysis. Clinical randomized controlled trials related to acupuncture combined with Chinese herbal medicine for DN were included in this study. Research selection, data extraction, and research quality assessments were independently completed by two researchers. We then assessed the quality and risk of the included studies and observed the outcome measures. RESULTS: This study provides a high-quality synthesis to assess the effectiveness and safety of acupuncture combined with Chinese herbal medicine for treating DN. CONCLUSION: This systematic review will provide evidence to determine whether acupuncture combined with Chinese herbal medicine is an effective and safe intervention for patients with DN. ETHICS AND DISSEMINATION: The protocol of the systematic review does not require ethical approval because it does not involve humans. This article will be published in peer-reviewed journals and presented at relevant conferences. REGISTRATION NUMBER: INPLASY202180018.


Assuntos
Terapia por Acupuntura/normas , Protocolos Clínicos , Nefropatias Diabéticas/tratamento farmacológico , Medicamentos de Ervas Chinesas/normas , Terapia por Acupuntura/métodos , Terapia por Acupuntura/estatística & dados numéricos , Nefropatias Diabéticas/fisiopatologia , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Metanálise como Assunto , Revisões Sistemáticas como Assunto , Resultado do Tratamento
6.
BMC Musculoskelet Disord ; 22(1): 761, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34488716

RESUMO

BACKGROUND: Up to now in the surgical treatment of Kümmell's disease combined with thoracolumbar kyphosis, little research has focused on the evaluation of the imaging and clinical outcomes of restoring the normal alignment and sagittal balance of the spine. This study aimed to evaluate the short to mid-term radiographic and clinical outcomes in the treatment of Kümmell's disease with thoracolumbar kyphosis. METHODS: From February 2016 to May 2018, 30 cases of Kümmell's disease with thoracolumbar kyphosis were divided into group A and B according to whether the kyphosis was combined with neurological deficits. All of the cases underwent surgical treatment to regain the normal spinal alignment and sagittal balance. The radiographic outcomes and clinical outcomes of the cases were retrospectively evaluated. The sagittal imaging parameters including sagittal vertebral axis (SVA),thoracic kyphosis (TK),thoracolumbar kyphosis (TLK),lumbar lordosis (LL),pelvic incidence (PI),pelvic tilt (PT),and sacral slope (SS) before operation,immediately after operation,and the last follow-up of each case were measured and evaluated. The clinical results included the Oswestry Disability Index (ODI) and the Numerical Rating Scale (NRS) of the two groups. Statistical software SPSS21.0 was used to analyze the data. RESULTS: In group A: Mean SVA before operation was 75 mm and 26.7 mm at the final postoperative evaluation (P = 0.000); Mean TLK before operation was 39°, and 7.1° at the final postoperative evaluation (P = 0.000); Mean NRS before operation was 4.7, compared with 0.9 at the final postoperative evaluation (P = 0.000). In group B: Mean preoperative SVA was 62.5 mm and decreases to 30.7 mm at the final postoperative evaluation (P = 0.000); Mean TLK before operation was 33°, and 9.7° 2 years post-operation (P = 0.000); Mean NRS prior to surgery was 4.0, and 0.8 at the last follow-up evaluation (P = 0.000). The improvement of the NRS scores of groups A and B was related to the improvement of the cobb angle (P = 0.020); (P = 0.009) respectively. CONCLUSION: In the treatment of Kümmell's disease with thoracolumbar kyphosis,to restore the normal alignment and sagittal balance can obtain a satisfactory radiographic and clinical short and medium-term effects.


Assuntos
Cifose , Lordose , Seguimentos , Humanos , Cifose/diagnóstico por imagem , Cifose/cirurgia , Lordose/diagnóstico por imagem , Lordose/cirurgia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Estudos Retrospectivos , Sacro , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/cirurgia , Resultado do Tratamento
7.
Oxid Med Cell Longev ; 2021: 9979706, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34504645

RESUMO

Angiotensin II- (Ang II-) induced cardiac hypertrophy and apoptosis are major characteristics of early-stage heart failure. Choline exerts cardioprotective effects; however, its effects on Ang II-induced cardiomyocyte apoptosis are unclear. In this study, the role and underlying mechanism of choline in regulating Ang II-induced cardiomyocyte apoptosis were investigated using a model of cardiomyocyte apoptosis, which was induced by exposing neonatal rat cardiomyocytes to Ang II (10-6 M, 48 h). Choline promoted heat shock transcription factor 1 (HSF1) nuclear translocation and the intracellular domain of Notch1 (NICD) expression. Consequently, choline attenuated Ang II-induced increases in mitochondrial reactive oxygen species (mtROS) and promotion of proapoptotic protein release from mitochondria, including cytochrome c, Omi/high-temperature requirement protein A2, and second mitochondrial activator of caspases/direct inhibitor of apoptosis-binding protein with low P. The reversion of these events attenuated Ang II-induced increases in cardiomyocyte size and numbers of terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling-positive cells, presumably via type 3 muscarinic acetylcholine receptor (M3AChR). Indeed, downregulation of M3AChR or Notch1 blocked choline-mediated upregulation of NICD and nuclear HSF1 expression, as well as inhibited mitochondrial apoptosis pathway and cardiomyocyte apoptosis, indicating that M3AChR and Notch1/HSF1 activation confer the protective effects of choline. In vivo studies were performed in parallel, in which rats were infused with Ang II for 4 weeks to induce cardiac apoptosis. The results showed that choline alleviated cardiac remodeling and apoptosis of Ang II-infused rats in a manner related to activation of the Notch1/HSF1 pathway, consistent with the in vitro findings. Taken together, our results reveal that choline impedes oxidative damage and cardiomyocyte apoptosis by activating M3AChR and Notch1/HSF1 antioxidant signaling, and suggest a novel role for the Notch1/HSF1 signaling pathway in the modulation of cardiomyocyte apoptosis.

8.
BMC Anesthesiol ; 21(1): 203, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34399695

RESUMO

BACKGROUND: Cerebral ischemia/reperfusion injury (CIRI) is a complication of surgical procedure associated with high mortality. The protective effect of dexmedetomidine (DEX) on CIRI has been explored in previous works, yet the underlying molecular mechanism remains unclear. Our study explored the protective effect of DEX and its regulatory mechanism on CIRI. METHODS: A CIRI rat model was established using middle cerebral artery occlusion (MCAO). Neurological deficit scores for rats received MCAO modeling or DEX treatment were measured. Cerebral infarction area of rats was detected by TTC staining, while damage of neurons in hippocampal regions of rats was determined by hematoxylin-eosin (HE) staining. Apoptosis rate of neurons in hippocampal regions was examined by TUNEL staining. The dual-luciferase assay was performed to detect the binding of microRNA-214 (miR-214) to Rho-associated kinase 1 (ROCK1). RESULTS: DEX treatment significantly reduced infarction area of MCAO rats and elevated miR-214 expression. Injection of miR-214 inhibitor attenuated the effect of DEX in MCAO rats by increasing the area of cerebral infarction in rats and apoptosis rate of hippocampal neurons. ROCK1 was targeted and negatively regulated by miR-214. The overexpression of ROCK1 led to activation of NF-κB to aggravate CIRI. CONCLUSION: Therapeutic effects of DEX on CIRI was elicited by overexpressing miR-214 and impairing ROCK1 expression and NF-κB activation. Our finding might provide novel insights into the molecular mechanism of DEX in rats with CIRI.

9.
Sci Total Environ ; 800: 149572, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34392221

RESUMO

The replacement of dominant sedges/grasses with secondary forbs is common in alpine rangelands, but the underlying plant ecological strategies and their relevance to leaf traits and their variabilities of different plant functional groups remain largely unknown. Here, we measured key leaf traits and analyzed the competitor, stress-tolerator and ruderal (CSR) strategies of major species with different functional groups (sedges, grasses and forbs) in an alpine meadow along a degradation gradient on the Tibetan Plateau. Our results indicated that S-selected species were dominant in both non-degraded (C:S:R = 1:95:4%) and severely degraded (C:S:R = 2:87:11%) meadows. However, there was a shift from S- to R-strategy in the communities after rangeland degradation. More specifically, sedges and grasses with a "conservative" strategy maintained stronger S-strategy to tolerate degraded and stressful conditions. In contrast, forbs with an "opportunistic" strategy (increase 9.5% in R-score) tended to adapt to degraded stages. Moreover, 51.1% and 23.9% of the increased R-scores in forbs were accounted by leaf mass per area and specific leaf area, respectively. Generally, higher leaf water and nitrogen contents coupled with larger variations in leaf traits and flexible SR strategies in forbs enabled them to capitalize on lower soil water and nutrient availability. Our findings highlighted that the contrasting strategies of plant species in response to the decrease in available resources might lead to niche expansion of secondary forbs and loss of diversity in the degraded alpine meadow. The emerging alternative stable states in the degraded rangelands might bring about a predicament for rangeland restoration.

10.
Transl Vis Sci Technol ; 10(9): 16, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34398225

RESUMO

Purpose: The purpose of this study was to assess the accuracy of artificial neural networks (ANN) in estimating the severity of mean deviation (MD) from peripapillary retinal nerve fiber layer (RNFL) thickness measurements derived from optical coherence tomography (OCT). Methods: Models were trained using 1796 pairs of visual field and OCT measurements from 1796 eyes to estimate visual field MD from RNFL data. Multivariable linear regression, random forest regressor, support vector regressor, and 1D convolutional neural network (CNN) models with sectoral RNFL thickness measurements were examined. Three independent subsets consisting of 698, 256, and 691 pairs of visual field and OCT measurements were used to validate the models. Estimation errors were visualized to assess model performance subjectively. Mean absolute error (MAE), root mean square error (RMSE), median absolute error, Pearson correlation, and R-squared metrics were used to assess model performance objectively. Results: The MAE and RMSE of the ANN model based on the testing dataset were 4.0 dB (95% confidence interval = 3.8-4.2) and 5.2 dB (95% confidence interval = 5.1-5.4), respectively. The ranges of MAE and RMSE of the ANN model on independent datasets were 3.3-5.9 dB and 4.4-8.4 dB, respectively. Conclusions: The proposed ANN model estimated MD from RNFL measurements better than multivariable linear regression model, random forest, support vector regressor, and 1-D CNN models. The model was generalizable to independent data from different centers and varying races. Translational Relevance: Successful development of ANN models may assist clinicians in assessing visual function in glaucoma based on objective OCT measures with less dependence on subjective visual field tests.

11.
Med Chem ; 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34463230

RESUMO

BACKGROUND: Mononcyclic ß-lactams are regarded as the most resistant class of ß-lactams against a series of ß-lactamases though possess limited antibacterial activity. Aztreonam being the first clinically approved monobactam needs broad-spectrum efficacy through structural modification. OBJECTIVE: We strive to synthesize a number of monocyclic ß-lactams by varying the substituents at N1, C3 and C4 positions of azetidinone ring and study the antimicrobial effect on variable bacterial strains. METHODS: Seven new monobactam derivatives 23a-g, containing substituted-amidine moieties linked to the azetidinone ring via thiazole linker, were synthesized through multistep synthesis. The final compounds were investigated for their in vitro antibacterial activities using broth microdilution method, against ten bacterial strains of clinical interest. The minimum inhibitory concentrations (MICs) of newly synthesized derivatives were compared with aztreonam, ceftazidime and meropenem, existing clinical antibiotics. RESULTS: All compounds 23a-g showed higher antibacterial activities (MIC 0.25 µg/mL to 64 µg/mL) against tested strains as compared to aztreonam (MIC 16 µg/mL to >64 µg/mL) and ceftazidime (MIC >64 µg/mL). However all compounds, except 23d, exhibited lower antibacterial activity against all tested bacterial strains as compared to meropenem. CONCLUSION: Compound 23d showed comparable or improved antibacterial activity (MIC 0.25 µg/mL to 2 µg/mL) to meropenem (MIC 1 µg/mL to 2 µg/mL) in case of seven bacterial species. Therefore, compound 23d may be valuable lead target for further investigations against multi-drug resistant Gram-negative bacteria.

12.
Exp Brain Res ; 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34463828

RESUMO

The purpose of this study is to clarify that exercise may improve the motor dysfunction of Parkinson's disease (PD) model rats by increasing the reuptake of glutamate (Glu) in the striatum. The neurotoxin 6-hydroxydopamine (6-OHDA) was injected into the medial forebrain bundle (MFB) of the rats' right brain to establish PD model rats with unilateral injury, and the sham operation group was given the same dose of normal saline at the same site as the control group. The reliability of the model was evaluated by apomorphine (APO)-induced rotation test combined with tyrosine hydroxylase (TH) immunohistochemical staining in the substantia nigra and striatum. The exercise group started treadmill training intervention (11 m/min, 30 min/day, 5d/week, and 4 weeks in total) 1 week after the operation. The balance bar test, suspension test, and the tail-lifting handstand test were used to evaluate exercise performance of rats; RT-PCR and western blotting were used to detect protein and mRNA expression of glutamate transporter-1 (GLT-1) and glutamine synthetase (GS) in the striatum; and isotope labeling was used to detect the ability of Glu reuptake in the striatum. (1) Compared with PD group, the number of TH immunoreactive cells in the substantia nigra and the content of TH immunoreactive fibers in the striatum did not change significantly in PD + Ex group. (2) Compared with PD group, the latency and total time of crossing the balance beam were significantly shorter (P < 0.01), the retention time of two forepaws on the metal wire was significantly longer (P < 0.01), the maximum lifting of head and trunk was significantly increased (P < 0.01) in PD + Ex group. (3) Compared with PD group, the ability of Glu reuptake in the striatum was significantly increased (P < 0.05), the expression levels of GLT-1 and GS mRNA in the striatum were significantly increased (P < 0.05), the protein expression of GLT-1 and GS in the striatum was significantly upregulated (P < 0.05) in PD + Ex group. Exercise intervention can significantly improve the motor dysfunction of PD model rats, increase the ability of striatal Glu reuptake significantly, and upregulate the expression levels of GLT-1 and GS protein and GS mRNA significantly. Exercise intervention may increase the protein expression level of GLT-1 and increase the reuptake ability of Glu in the striatum, thereby reducing the excitotoxic effect of excessive Glu on the postsynaptic membrane, and ultimately alleviate the motor dysfunction in PD model rats.

13.
Chem Asian J ; 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34431617

RESUMO

The construction of a heterogeneous nanocatalyst with outstanding catalytic performance via an environmentally benign and cost-effective synthetic category has long been one of the challenges in nanotechnology. Herein, we synthesized highly efficient and low-cost mesoporous morphology-dependent CuO/CeO2-Rods and CuO/CeO2-Cubes catalysts by employing a green and multifunctional polyphenolic compound (tannic acid) as the stabilizer and chelating agent for 4-Nitrophenol (4-NP) reduction reaction. The CuO/CeO2-Rods exhibited excellent performance, of which the activity was 3.2 times higher than that of CuO/CeO2-Cubes. This can be connected with the higher density of oxygen vacancy on CeO2-Rods (110) than CeO2-Cubes (100), the oxygen vacancy favors anchoring CuO species on the CeO2 support, which promotes the strong interaction between finely dispersed CuO and CeO2-Rods at the interfacial positions and facilitates the electron transfer from BH4- to 4-NP. The synergistic catalytic mechanism illustrated that 4-NP molecules preferentially adsorbed on the CeO2, while H2 from BH4- dissociated over CuO to form highly active H* species, contributing to achieving efficient hydrogenation of 4-NP. This study is expected to shed light on designing and synthesizing cost-effective and high-performance nanocatalysts through a greener synthetic method for the areas of catalysis, nanomaterial science and engineering, and chemical synthesis.

14.
Environ Res ; 203: 111894, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34418448

RESUMO

The Tibetan Plateau (TP) has a variety of vegetation types that range from alpine tundra to tropic evergreen forest, which play an important role in the global carbon (C) cycle and is extremely vulnerable to climate change. The vegetation C uptake is crucial to the ecosystem C sequestration. Moreover, net reduction in vegetation C uptake (NRVCU) will strongly affect the C balance of terrestrial ecosystem. Until now, there is limited knowledge on the recovery process of vegetation net C uptake and the spatial-temporal patterns of NRVCU after the disturbance that caused by climate change and human activities. Here, we used the MODIS-derived net primary production to characterize the spatial-temporal patterns of NRVCU. We further explored the influence factors of the net reduction rate in vegetation C uptake (NRRVCU) and recovery processes of vegetation net C uptake across a unique gradient zone on the TP. Results showed that the total net reduction amount of vegetation C uptake gradually decreased from 2000 to 2015 on the TP (Slope = -0.002, P < 0.05). Specifically, an increasing gradient zone of multi-year average of net reduction rate in vegetation carbon uptake (MYANRRVCU) from east to west was observed. In addition, we found that the recovery of vegetation net C uptake after the disturbance caused by climate change and anthropogenic disturbance in the gradient zone were primarily dominated by precipitation and temperature. The findings revealed that the effects of climate change on MYANRRVCU and vegetation net C uptake recovery differed significantly across geographical space and vegetation types. Our results highlight that the biogeographic characteristics of the TP should be considered for combating future climate change.

15.
Environ Pollut ; 286: 117573, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34438495

RESUMO

Solid fuel is a the most dominant energy source for household usages in developing countries. In this study, emission characteristics on organic carbon (OC), elemental carbon (EC) and fifty-two polycyclic aromatic hydrocarbons (PAHs) in gaseous and particulate phases from seven fuel-stove combinations were studied in a typical rural village in northwest China. For the PAHs, the highest gaseous and particulate phase emission factors (EFs) were both observed for bituminous coal with one-stage stoves, ranging from 459 ± 154 to 1.09 ± 0.36 × 103 mg kg-1. In contrast, the PAHs EFs for the clean briquette coal with two-stage stoves were two orders of magnitude lower than those of the bituminous coals. For parent PAHs (pPAHs) and total quantified PAHs (∑PAHs), they mainly contributed in gaseous phases with compositions of 69-79% and 64-70%, respectively. The gas-to-particle partitioning was mostly governed by the absorption. Moreover, the correlation coefficient (r) between EC and ∑PAHs, OC and parent PAHs (pPAHs), OC and nitro PAHs (nPAHs) were 0.81, 0.67 and 0.85, respectively, supporting that the PAHs species were potential precursors to the EC formation during the solid fuel combustion. The correlation analyses in this study further deduced that the formations of pPAHs and nPAHs were more closely related to that of OC than alkylated PAHs (aPAHs) and oxygenated PAHs (oPAHs). Diagnostic ratios of selective PAHs were calculated and evaluated as well. Among those, the ratio of retene (RET)/[RET + chyrene (CHR)] was found to be an efficient tool to distinguish coal combustion and biomass burning. In general, it was found that the amounts of pollutant emissions from clean briquette coal combustion were definitely lower than those from bituminous coal and biomass combustions. It is thus necessary to introduce and recommend the use of cleaner briquette coal as energy source.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , China , Carvão Mineral/análise , Monitoramento Ambiental , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise
16.
Sensors (Basel) ; 21(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34451016

RESUMO

Fully exploring the correlation of local features and their spatial distribution in point clouds is essential for feature modeling. This paper, inspired by convolutional neural networks (CNNs), explores the relationship between local patterns and point coordinates from a novel perspective and proposes a lightweight structure based on multi-scale features and a two-step fusion strategy. Specifically, local features of multi-scales and their spatial distribution can be regarded as independent features corresponding to different levels of geometric significance, which are extracted by multiple parallel branches and then merged on multiple levels. In this way, the proposed model generates a shape-level representation that contains rich local characteristics and the spatial relationship between them. Moreover, with the shared multi-layer perceptrons (MLPs) as basic operators, the proposed structure is so concise that it converges rapidly, and so we introduce the snapshot ensemble to improve performance further. The model is evaluated on classification and part segmentation tasks. The experiments prove that our model achieves on-par or better performance than previous state-of-the-art (SOTA) methods.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação
17.
Artigo em Inglês | MEDLINE | ID: mdl-34435389

RESUMO

It is unclear that whether Urban and Rural Resident Basic Medical Insurance (URRBMI) is associated with depressive symptoms among middle-aged and older adults. To fulfill this research gap, this study aimed to investigate the association between URRBMI and depressive symptoms among the middle-aged and older adults in China. This data of this study was sourced from the 2018 wave of China Health and Retirement Longitudinal Study (CHARLS). Ordinary least squares (OLS) regression models were used to explore the association between URRBMI and depressive symptoms. Instrumental variable (IV) method was employed to address potential endogeneity problem which is caused by reverse causation and omitted variable bias. Propensity score matching (PSM) and doubly robust estimation were employed to conduct robustness checks. We provide robust evidence indicating that participation of URRBMI was significantly correlated with a reduced depression score. Moreover, we find that improving the utilization of inpatient and outpatient care may be important channels through which URRBMI relieved depressive symptoms.

18.
J Dent ; 113: 103772, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34363893

RESUMO

OBJECTIVE: A novel composite resin (CR) with fluorine-doped nano-zirconia (F-ZrO2) fillers was developed as an antibacterial restorative material. This article described the synthesis and investigated the fluoride release, antibacterial property and cytotoxicity of the novel CR. METHODS: F-ZrO2 powders with different fluorine contents (0% F-ZrO2, 5% F-ZrO2, 10% F-ZrO2 or 20% F-ZrO2) were synthesized by chemical precipitation method and characterized by XRD, SEM and TEM-EDS. The content and release of fluoride were also determined. 20% F-ZrO2 powers were selected to develop the novel CRs (FZ-25, FZ-50, and FZ-75). The fluoride release from the novel CRs during 28 days was recorded. The antibacterial property of the novel CRs was investigated with direct contact test (DCT) and metabolic activity test (CCK8). The cytotoxicity of the CRs was also evaluated here. RESULTS: F-ZrO2 powders with different fluorine contents were obtained. The fluoride release increased with increasing of the fluoride content. Through the antibacterial performance evaluation, 20% F-ZrO2 powders, which exhibiting the best antibacterial property, were selected as the fillers for preparing the novel CR. The novel CR with F-ZrO2 fillers exhibited an effective antibacterial effect. Compared with the control group, the antibacterial rates of FZ-25, FZ-50 and FZ-75 were 51.65%, 54.14% and 66.80% (p<0.05), respectively. No obvious cytotoxicity of the novel CR was detected in this study. CLINICAL SIGNIFICANCE: The novel CR with continuous fluoride release and proper antibacterial property is expected to be used as an antibacterial material to reduce secondary caries.

19.
Ann Med ; 53(1): 1328-1339, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34409894

RESUMO

Antiphospholipid syndrome (APS) is an autoimmune disease mainly characterised by vascular thrombosis and pregnancy morbidity. APS has broad spectrum of clinical manifestations. The digestive system involvement of antiphospholipid syndrome is a critical but under-recognised condition. Digestive system involvement may be the result of direct (autoimmune-mediated) or indirect (thrombotic) mechanisms. Liver is the most commonly involved organ, followed by intestines, oesophagus, stomach, pancreas and spleen. This review describes possible digestive system manifestations in APS patients, and illustrates the epidemiology and possible pathophysiology of APS. The role of different treatment strategies in the management of digestive system manifestations of APS were also discussed.Key messagesAntiphospholipid syndrome is a multi-organ, multi-system disease and its clinical manifestation spectrum is gradually expanding. Since the first diagnosis of APS, the clinical manifestations of digestive system have been reported successively. This narrative review describes the major digestive system manifestations of APS and illustrates the epidemiology, pathophysiology and the role of therapeutic strategies of these patients.

20.
Ecotoxicol Environ Saf ; 224: 112680, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34418851

RESUMO

PM2.5 Road dust samples were collected from 10 representative cities in southern and northern China for examination of chemical components and oxidative stress levels in A549 cells. Downtown road dust was abundance of heavy metals, EC and PAHs compared to nondowntown road dust. Source apportionment also revealed the relative higher contribution of vehicle emission to downtown (35.8%) than nondowntown road dust (25.5%). Consequently, downtown road dust induced much higher intracellular reactive oxidative species (ROS) levels than that from nondowntown (p < 0.05). This study highlights that the ROS-inducing capacity of road dust in China is lower at lower latitudes, which resulted in a significantly higher ROS-inducing capacity of road dust from northern cities than southern ones. Hotspot analysis demonstrated that heavy metals (i.e., Cr, Zn, Cu and Pb) in road dust were the most closely associated with ROS production in A549 cells. Vehicle emission and combustion emission in road dust were identified to be correlated with cellular ROS production. The findings highlight the ROS-inducing effect of PM2.5 road dust and also serve as a reference to make the targeted solutions for urban road dust pollution control, especially from a public health perspective.

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