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1.
BMC Ophthalmol ; 24(1): 71, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360630

RESUMO

OBJECTIVE: To study the changes of retinal function in type 2 diabetes mellitus(DM) patients without apparently diabetic retinopathy via multifocal electroretinogram. METHODS: Thirty-six type 2 DM patients (72 eyes) without visible diabetic retinopathy were selected as the experimental group, and thirty-five healthy subjects (70 eyes) were selected as the control group. All subjects were underwent multifocal electroretinogram (mf- ERG). RESULTS: Compared with the control group, the implicit time delay of the P1 wave in the first ring, third ring, fourth ring, and fifth ring of the experimental group was significant (t = -3.154, p = 0.004, t = -8.21, p = 0.000, t = -3.067, p = 0.004, t = -4.443, p = 0.000, respectively). The implicit time of the N1 wave in the fourth- and fifth-ring were also significantly delayed compared with the control group (t = -3.549, p = 0.001, t = 2.961, p = 0.005, respectively). Compared with the control group, the implicit time of the P1 wave and N1 wave in the temporal region of the experimental group were delayed (t = -2.148, p = 0.037, t = -2.834, p = 0.007, respectively). There were no significant difference between the experimental group and the control group of the temporal area in the amplitude density of P1 wave, N1 wave. There was no difference in the implicit time and amplitude density of the N1 and P1 waves in the nasal region between the experimental group and the control group. The multifocal electroretinogram complex parameters showed better specificity and sensitivity in the diagnosis of diabetic retinopathy. CONCLUSION: The multifocal electroretinogram can detect abnormal changes in the retina of type 2 DM patients without visible diabetic retinopathy. The multifocal electroretinogram complex parameter is a potential indicator for the early diagnosis of diabetic retinopathy.


Assuntos
Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Humanos , Retinopatia Diabética/diagnóstico , Diabetes Mellitus Tipo 2/complicações , Retina , Eletrorretinografia , Acuidade Visual
2.
Asia Pac J Clin Nutr ; 33(1): 94-1013, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38494691

RESUMO

BACKGROUND AND OBJECTIVES: It is recommended by Asian Working Group for Sarcopenia to early identify people at risk for sarcopenia using simple screening tools like SARC-F. The modified version SARC-F+EBM showed higher diagnostic performance. However, this cut-off value of body mass index (BMI) remained uncertain to be used in Chinese population. In this study, we used appropriate BMI recommended for Chinese older population and further modified SARC-F+EBM by combining calf circumference. METHODS AND STUDY DESIGN: Diagnostic tests were performed and the receiver operating characteristics analyses were conducted between the SARC-F, SARC-F+EBM (cut-off of BMI: ≤ 21 kg/m2), SARC-F+EBM (CN) (cut-off of BMI: ≤ 22 kg/m2), SARC-CalF and SARC-CalF+EBM (CN) (cut-off of BMI: ≤ 22 kg/m2) in 1660 community-dwelling participants aged ≥ 65 years from China. RESULTS: The participants had an average age of 71.7±5.1 years, of which 56.8% were women. All the modified models could enhance the areas under the receiver operating characteristic curve (AUC) of original SARC-F (all p<0.001). The SARC-F+EBM (CN) also showed a significantly higher sensitivity of 47.4% (p<0.001) and an AUC of 0.809 (p=0.005) than SARC-F+EBM. SARC-CalF+EBM (CN) was validated to be of great diagnostic value of the highest AUC of 0.88 among these sarcopenia screening tools, including SARC-F, SARC-CalF and SARC-F+EBM (CN) (all p<0.001). Using this study population as a reference, the optimal cut-off value of SARC-CalF+EBM (CN) is ≥12 points, with a sensitivity of 79.3% and a specificity of 80.7%. CONCLUSIONS: The SARC-F+EBM (CN) and SARC-CalF+EBM (CN) could enhance the diagnostic performance of SARC-F and SARC-F+EBM and are suitable sarcopenia screening tools for Chinese population.


Assuntos
Sarcopenia , Humanos , Feminino , Idoso , Masculino , Sarcopenia/diagnóstico , Sarcopenia/epidemiologia , Programas de Rastreamento/métodos , Curva ROC , Vida Independente , China/epidemiologia , Avaliação Geriátrica/métodos , Inquéritos e Questionários
3.
Chin Med Sci J ; 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38755752

RESUMO

Objective To investigate the efficacy of raw corn starch (RCS) in clinical management of insulinoma-induced hypoglycemia.Methods We retrospectively collected clinical data of insulinoma patients who received RCS-supplemented diet preoperatively, and analyzed the therapeutic effects of the RCS intervention on blood glucose control, weight change, and its adverse events.Results The study population consisted of 24 case of insulinoma patients, 7 males and 17 females, aged 46.08 ± 14.15 years. Before RCS-supplemented diet, all patients had frequent hypoglycemic episodes (2.51 ± 3.88 times/week), concurrent with neuroglycopenia (in 83.3% of patients) and autonomic manifestations (in 75.0% of patients), with the median fasting blood glucose (FBG) of 2.70 [interquartile range (IQR): 2.50-2.90] mmol/L. The patients' weight increased by 0.38 (IQR: 0.05-0.65) kg per month, with 8 (33.3%) cases developing overweight and 7 (29.2%) cases developing obesity. All patients maintained the RCS-supplemented diet until they underwent tumor resection (23 cases) and transarterial chemoembolization for liver metastases (1 case). For 19 patients receiving RCS throughout the day, the median FBG within one week of nutritional management was 4.30 (IQR: 3.30-5.70) mmol/L, which was a significant increase compared to pre-nutritional level [2.25 (IQR: 1.60-2.90) mmol/L; P = 0.000]. Of them, 10 patients receiving RCS throughout the day for over four weeks had sustained improvement in FBG compared to pre-treatment [3.20 (IQR: 2.60-3.95) mmol/L vs. 2.15 (IQR: 1.83-2.33) mmol/L; P = 0.000). Five patients who received RCS only at night also had a significant increase in FBG within one week of nutritional management [3.50 (IQR: 2.50-3.65) mmol/L vs. 2.20 (IQR:1.80-2.60) mmol/L; P = 0.000], but only one patient who continued to receive RCS for over 4 weeks did not have a significant improvement in FBG. No improvement in weight gain was observed upon RCS supplementation. Mild diarrhea (2 cases) and flatulence (1 case) occurred, and were relieved by reduction of RCS dose.Conclusion The RCS-supplemented diet is effective in controlling insulinoma-induced hypoglycemia.

4.
Acta Pharmacol Sin ; 44(9): 1826-1840, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37095199

RESUMO

Obesity contributes to the progression of various chronic diseases, and shortens life expectancy. With abundant mitochondria, brown adipose tissue (BAT) dissipates energy through heat to limit weight gain and metabolic dysfunction in obesity. Our previous studies have shown that aurantio-obtusin (AO), a bioactive ingredient in Chinese traditional medicine Cassiae semen significantly improves hepatic lipid metabolism in a steatotic mouse model. In the current study we investigated the effects of AO on lipid metabolism in the BAT of diet-induced obesity mice and in oleic acid and palmitic acid (OAPA)-stimulated primary mature BAT adipocytes. Obese mice were established by feeding a HFHS diet for 4 weeks, and then administered AO (10 mg/kg, i.g.) for another 4 weeks. We showed that AO administration significantly increased the weight of BAT and accelerated energy expenditure to protect the weight increase in the obese mice. Using RNA sequencing and molecular biology analysis we found that AO significantly enhanced mitochondrial metabolism and UCP1 expression by activating PPARα both in vivo and in vitro in the primary BAT adipocytes. Interestingly, AO administration did not improve metabolic dysfunction in the liver and white adipose tissue of obese mice after interscapular BAT excision. We demonstrated that low temperature, a trigger of BAT thermogenesis, was not a decisive factor for AO to stimulate the growth and activation of BATs. This study uncovers a regulatory network of AO in activating BAT-dependent lipid consumption and brings up a new avenue for the pharmaceutical intervention in obesity and related comorbidities.


Assuntos
Tecido Adiposo Marrom , PPAR alfa , Camundongos , Animais , Tecido Adiposo Marrom/metabolismo , PPAR alfa/metabolismo , Camundongos Obesos , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Mitocôndrias/metabolismo , Metabolismo Energético , Tecido Adiposo Branco/metabolismo , Termogênese , Camundongos Endogâmicos C57BL
5.
Cereb Cortex ; 32(4): 824-838, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-34383018

RESUMO

Sleep deprivation (SD) causes deficits in off-line memory consolidation, but the underlying network oscillation mechanisms remain unclear. Hippocampal sharp wave ripple (SWR) oscillations play a critical role in off-line memory consolidation. Therefore, we trained mice to learn a hippocampus-dependent trace eyeblink conditioning (tEBC) task and explored the influence of 1.5-h postlearning SD on hippocampal SWRs and related spike dynamics during recovery sleep. We found an increase in hippocampal SWRs during postlearning sleep, which predicted the consolidation of tEBC in conditioned mice. In contrast, sleep-deprived mice showed a loss of tEBC learning-induced increase in hippocampal SWRs during recovery sleep. Moreover, the sleep-deprived mice exhibited weaker reactivation of tEBC learning-associated pyramidal cells in hippocampal SWRs during recovery sleep. In line with these findings, tEBC consolidation was impaired in sleep-deprived mice. Furthermore, sleep-deprived mice showed augmented fast excitation from pyramidal cells to interneurons and enhanced participation of interneurons in hippocampal SWRs during recovery sleep. Among various interneurons, parvalbumin-expressing interneurons specifically exhibited overexcitation during hippocampal SWRs. Our findings suggest that altered hippocampal SWRs and associated spike dynamics during recovery sleep may be candidate network oscillation mechanisms underlying SD-induced memory deficits.


Assuntos
Hipocampo , Privação do Sono , Animais , Hipocampo/fisiologia , Camundongos , Parvalbuminas/metabolismo , Células Piramidais/fisiologia , Sono
6.
BMC Ophthalmol ; 23(1): 173, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37095450

RESUMO

AIM: To evaluate association between pretreatment serum metrics and best corrected visual acuity ( BCVA) of patients with macular edema secondary to retinal vein occlusion and its subtypes after intravitreal ranibizumab or conbercept implant. METHODS: This prospective research included 201 patients(201 eyes) who were diagnosed with macular edema secondary to retinal vein occlusion at Heibei Eye Hospital between January 2020 and January 2021, who all received intravitreal anti- vascular endothelial growth factor treatment. Serum metrics were measured before the first treatment, and correlations between BCVA and each of four parameters- platelets, neutrophil- to- lymphocyte ratio(NLR), platelet- to- lymphocyte ratio(PLR) and monocyte- to- lymphocyte ratio(MLR)- were analyzed to identify predictors of effective intravitreal injection treatment outcomes. RESULTS: The mean platelets was significantly different in the effective and ineffective group for RVO-ME (273.02 ± 41.49 × 109/L,214.54 ± 44.08 × 109/L P < 0.01),BRVO-ME (269.43 ± 49.52 × 109/L,214.72 ± 40.42 × 109/L P < 0.01), and CRVO-ME (262.32 ± 32.41 × 109/L,209.27 ± 42 0.91 × 109/L P < 0.01). The cutoff value of the platelets was 266.500, the area under the curve was 0.857,and the sensitivity and specificity were 59.8% and 93.6%, respectively. The mean PLR was significantly different in the effective and ineffective group for RVO-ME (154.66 ± 49.60, 122.77± 44.63 P < 0.01),BRVO-ME (152.24 ± 54.99, 124.72 ± 41.46 P = 0.003), and CRVO-ME (152.06±44.23, 118.67 ± 41.80 P = 0.001). The cutoff value of the platelets was 126.734, the area under the curve was 0.699, and the sensitivity and specificity were 70.7% and 63.3%, respectively. There were no statistical differencies between the effective and ineffective group(RVO- ME and its subtypes) in NLR and MLR. CONCLUSION: Higher pretreatment platelets and PLR were associated with BCVA in patients with RVO- ME and its subtypes who were treated with anti- VEGF drugs. The platelets and PLR may be used as predictive and prognostic tools for effective intravitreal injection treatment outcomes.


Assuntos
Edema Macular , Oclusão da Veia Retiniana , Humanos , Oclusão da Veia Retiniana/tratamento farmacológico , Edema Macular/tratamento farmacológico , Fator A de Crescimento do Endotélio Vascular , Dexametasona , Glucocorticoides , Estudos Prospectivos , Tomografia de Coerência Óptica , Resultado do Tratamento , Injeções Intravítreas , Inibidores da Angiogênese/uso terapêutico
7.
Sensors (Basel) ; 23(4)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36850835

RESUMO

The VIIRS instrument (Visible Infrared Imaging Radiometer Suite) on board the SNPP (Suomi National Polar-orbiting Partnership) satellite contains 11 narrow channels (M1-M11) in the 0.4-2.5 µm solar spectral region. The M9 channel is specifically designed for detecting thin cirrus clouds. It is centered at 1.378 µm with a width of 15 nm, which is located within a strong atmospheric water vapor band absorption region. In comparison with the corresponding MODIS Channel 26, the VIIRS M9 channel is narrower and more sensitive for cirrus detections. Because the radiances of the M9 channel over cirrus pixels are subjected to absorption by atmospheric water vapor molecules above and within the cirrus clouds, the water vapor absorption effect needs to be properly taken into consideration when using the M9 channel for quantitative removal of cirrus effects in other VIIRS channels in the 0.4-2.5 µm spectral range. In this article, we describe in detail an empirical technique for the retrieval of cirrus reflectances in the visible and near-IR (VNIR, 0.4-1.0 µm), where ice particles within cirrus clouds have negligible absorption effects, and in shortwave IR (SWIR, 1.0-2.5 µm) where ice particles' absorption effects are observed. The descriptions include all elements leading to the development of the operational VIIRS cirrus reflectance algorithm, the journal literature backing up the approach, theoretical descriptions of the algorithm's physics and mathematical background, and sample retrieval results from the VIIRS data. The SNPP VIIRS cirrus reflectance data products from 1 March 2012 to the present are available from a NASA data center.

8.
Amino Acids ; 54(12): 1541-1552, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35939077

RESUMO

The post-translational modifications (PTMs), which are crucial in the regulation of protein functions, have great potential as biomarkers of cancer status. Fascin (Fascin actin-bundling protein 1, FSCN1), a key protein in the formation of filopodia that is structurally based on actin filaments (F-actin), is significantly associated with tumor invasion and metastasis. Studies have revealed various regulatory mechanisms of human Fascin, including PTMs. Although a number of Fascin PTM sites have been identified, their exact functions and clinical significance are much less explored. This review explores studies on the functions of Fascin and briefly discusses the regulatory mechanisms of Fascin. Next, to review the role of Fascin PTMs in cell biology and their associations with metastatic disease, we discuss the advances in the characterization of Fascin PTMs, including phosphorylation, ubiquitination, sumoylation, and acetylation, and the main regulatory mechanisms are discussed. Fascin PTMs may be potential targets for therapy for metastatic disease.


Assuntos
Citoesqueleto de Actina , Pseudópodes , Humanos , Linhagem Celular Tumoral , Pseudópodes/metabolismo , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo
9.
Arch Insect Biochem Physiol ; 111(1): e21921, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35635368

RESUMO

The oriental armyworm Mythimna separata (Walker) is a devastating pest of cereal crops mainly in Asia and Oceania and recently become resistant to beta-cypermethrin (beta-CP). However, molecular biological studies of its response to beta-CP are scarce, and related genomic information is not available. In this study, we sequenced and de novo assembled the transcriptome of beta-CP susceptible M. separata (MsS-whole, abbr. MsS-W). A total of 30,486 unigenes were obtained, with an N50 length of 506 bp. A number of 21,051 unigenes were matched to public databases, of which 10,107 were classified into 59 gene ontology subcategories, 5792 were assigned into 25 clusters of orthologous groups of proteins subgroups and 12,123 were assigned to 257 Kyoto Encyclopedia of Genes and Genomes pathways. A total of 729 simple sequence repeats were detected. In addition, a total of 323 cytochrome P450-associated sequences from nine lepidopterous species, of which 130 were from M. separata, were analyzed using the maximum likelihood method and Bayesian inference. Among the 130 cytochrome P450-associated sequences from M. separata, 60 were dropped into CYP3 clan, which is associated with metabolizing xenobiotics and plant natural compounds. Furthermore, the beta-CP susceptible (MsS-2) and resistant (MsR-2) M. separata population transcriptomes were sequenced. Certain critical genes involved in beta-CP detoxification were detected and verified by quantitative real-time polymerase chain reaction. Collectively, our results provided a basis for further studies of the molecular mechanism of insecticide resistance in M. separata.


Assuntos
Mariposas , Animais , Teorema de Bayes , Sistema Enzimático do Citocromo P-450 , Perfilação da Expressão Gênica , Anotação de Sequência Molecular , Piretrinas , Transcriptoma
10.
Neoplasma ; 69(5): 1079-1091, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35818964

RESUMO

Gastric cancer is the third most frequent cancer with high prevalence and mortality globally. Circular RNAs (circRNAs) play a key role in cancer regulation, including gastric cancer. Nevertheless, only a few circRNAs have been well elucidated in gastric cancer. Hence, we investigated the action of circ_0067514 on gastric cancer and clarified the underlying mechanism. Here, we found that circ_0067514 was decreased in gastric cancer patients and cancer cells. The circ_0067514 expression was correlated with gastric cancer overall survival, lymph node metastasis, tumor, node, metastasis (TNM) stage, and histological differentiation. Overexpression of circ_0067514 blocked proliferation, invasion, and glycolysis of gastric cancer cells. Besides, circ_0067514 regulated large tumor suppressor kinase 2 (LATS2) expression by absorbing microRNA (miR)-654-3p. Furthermore, circ_0067514 modulated gastric cancer aggressive behaviors and glycolysis via miR-654-3p/LATS2 axis. Moreover, circ_0067514 constrained tumor growth in vivo. Together, this study showed that circ_0067514 suppressed gastric cancer aggressive development and glycolysis via miR-654-3p/LATS2 axis, making circ_0067514 a valuable target for preventing gastric cancer progression.


Assuntos
MicroRNAs , Neoplasias Gástricas , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Glicólise/genética , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Serina-Treonina Quinases , RNA Circular/genética , Neoplasias Gástricas/patologia , Proteínas Supressoras de Tumor/genética
11.
BMC Ophthalmol ; 22(1): 162, 2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35395739

RESUMO

AIM: To study the short-term change of macular function and the correlates after intravitreal conbercept for CRVO-ME. STUDY DESIGN: Prospective, clinical study. METHODS: Twenty Three patients(23 eyes) were recruited, who were non-ischemia central retinal vein occlusion diagnosed by FFA (fundus fluorescein angiography) and treated with intravitreal conbercept for macular edema, best - corrected visual acuity ( BCVA), central macular thickness(CMT), amplitude density of P1 wave and implicit time of P1,N1 wave from ring 1 and ring 2 of mf-ERG were measured before and 1 week、2 month after treatment. RESULTS: Compared to the baseline, BCVA、CMT、amplitude density of P1 wave and implicit time of P1,N1 wave from ring 1 and ring 2 were greatly improved at 1 W、2 M after treatment; better results were gained at 2 M compared to 1 W; Pearson correlation analysis shows no significantly correlation between the improvement of mf-ERG with the change of BCVA、CMT. CONCLUSION: The BCVA、the structure and the function of macular were greatly improved after intravitreal conbercept for central retinal vein occlusion induced macular edema; however no significantly correlation between the improvement of the function of macular with the strcture of macular and BCVA.


Assuntos
Edema Macular , Oclusão da Veia Retiniana , Inibidores da Angiogênese/uso terapêutico , Angiofluoresceinografia , Humanos , Injeções Intravítreas , Edema Macular/diagnóstico , Edema Macular/tratamento farmacológico , Edema Macular/etiologia , Estudos Prospectivos , Proteínas Recombinantes de Fusão , Oclusão da Veia Retiniana/diagnóstico , Oclusão da Veia Retiniana/tratamento farmacológico , Tomografia de Coerência Óptica/métodos , Resultado do Tratamento , Acuidade Visual
12.
Anal Chem ; 93(39): 13311-13318, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34569224

RESUMO

As a global health challenge, hepatocellular carcinoma (HCC) is strongly associated with chronic inflammation. Targeting inflammation, particularly inflammatory factors, is regarded as an important strategy for HCC diagnosis and treatment. Pyroglutamic aminopeptidase I (PGP-I), a common exopeptidase, was recently identified as a novel inflammatory cytokine in cells. However, whether PGP-I is involved in HCC development and can be regarded as a biomarker remains unclear. To address this issue, endogenous PGP-I was imaged in live cells and in vivo, and the related biochemical and pathological processes were analyzed accordingly with a newly developed fluorogenic PGP-I biosensor. Bioimaging with the specific biosensor demonstrated the aberrant expression of PGP-I in HCC cell lines and tumor-bearing nude mice. Moreover, overexpression of PGP-I in HCC cells promoted tumor progression, whereas knockdown of PGP-I significantly suppressed tumor cell growth and migration. The activity of PGP-I was further identified to be highly related to the phosphorylation of STAT3, which could be impeded by the natural product parthenolide. Collectively, these findings suggest that PGP-I, which can promote hepatocellular tumor progression through the classical inflammation-/tumor-related IL-6/STAT3 pathway, may serve as a potential HCC biomarker and therapeutic target.


Assuntos
Técnicas Biossensoriais , Carcinoma Hepatocelular , Interleucina-6/metabolismo , Neoplasias Hepáticas , Piroglutamil-Peptidase I , Fator de Transcrição STAT3/metabolismo , Animais , Camundongos , Camundongos Nus , Ácido Pirrolidonocarboxílico
13.
Anal Chem ; 92(13): 9205-9213, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32512997

RESUMO

Carboxylesterases (CEs) exist as multiple types of isomers in humans, and two major types are CE1 and CE2. They are widely distributed in human tissues and well-known for their important roles in drug metabolism and pathology of various diseases. Thus, the detection of CEs in living systems could provide efficient proof in disease diagnostics, as well as important information regarding chemotherapeutic effects of antitumor drugs and prognosis. To develop a specific probe to discriminate CEs from other hydrolases, especially cholinesterases, is quite challenging due to their structural similarities and substrate specificity. To date, almost all of the fluorescent probes developed for CEs have been constructed with an acetyl group as the recognition unit. Herein we proposed a new design strategy of probe-cavity matching, which led to the identification of a new fluorogenic substrate (termed as HBT-CE) with high specificity toward both CE isomers and improved sensitivity, considering the higher binding affinity and catalysis efficiency. The promising capability of HBT-CE was further demonstrated for endogenous CEs imaging in living cells, zebrafish, and nude mice. In addition, HBT-CE was successfully applied in kinetically monitoring drug-induced CE regulation in cancer cells. All of these findings suggest that HBT-CE is a valuable tool for tracking and imaging endogenous CEs in complex biological systems.


Assuntos
Carboxilesterase/metabolismo , Corantes Fluorescentes/metabolismo , Microscopia de Fluorescência/métodos , Animais , Benzotiazóis/química , Benzotiazóis/metabolismo , Linhagem Celular , Corantes Fluorescentes/química , Humanos , Isoenzimas/metabolismo , Cinética , Fígado/enzimologia , Camundongos , Camundongos Nus , Fenóis/química , Fenóis/metabolismo , Especificidade por Substrato , Imagem com Lapso de Tempo , Distribuição Tecidual , Peixe-Zebra/metabolismo
14.
Phys Rev Lett ; 124(11): 116802, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32242698

RESUMO

The exotic topological surface states of Dirac or Weyl semimetals, namely Fermi arcs, are predicted to be spin polarized, while their spin polarization nature is still not revealed by transport measurements. Here, we report the spin-polarized transport in a Dirac semimetal Cd_{3}As_{2} nanowire employing the ferromagnetic electrodes for spin detection. The spin-up and spin-down states can be changed by reversing the current polarity, showing the spin-momentum locking property. Moreover, the nonlocal measurements show a high fidelity of the spin signals, indicating the topological protection nature of the spin transport. As tuning the Fermi level away from the Dirac point by gate voltages, the spin signals gradually decrease and finally are turned off, which is consistent with the fact that the Fermi arc surface state has the maximum ratio near the Dirac point and disappears above the Lifshitz transition point. Our results should be valuable for revealing the transport properties of the spin-polarized Fermi arc surface states in topological semimetals.

15.
Anal Chem ; 91(6): 3877-3884, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30626182

RESUMO

Neutrophil elastase (NE), a typical hematopoietic serine protease, has significant roles in inflammatory and immune responses, and thus is highly associated with various diseases such as acute lung injury (ALI) and lung cancer. Rapid and accurate measurement of NE activity in biological systems is particularly important for understanding the role of NE in inflammatory diseases, as well as clinical diagnosis. However, the specific detection and noninvasive imaging of NE in vivo remains a challenge. To address this issue, a small-molecule substrate based near-infrared fluorogenic probe (NEP) for NE was constructed via incorporating pentafluoroethyl as the recognition group with a hemicyanine dye-based fluorophore. This initially quenched probe possesses more than 25-fold red fluorescence enhancement upon the catalysis of human NE, and the detection limit is about 29.6 ng/mL. In addition, the high specificity and the long emission wavelength (λemmax = 700 nm) of NEP allowed the direct monitoring of NE-trafficking, exogenous NE uptake, and endogenous NE upregulation at the cellular level. Moreover, the successful spatiotemporal imaging of NE in ALI model mice also made it a promising new tool in clinical diagnosis for ALI and other lung diseases.


Assuntos
Ensaios Enzimáticos/métodos , Corantes Fluorescentes/metabolismo , Raios Infravermelhos , Elastase de Leucócito/metabolismo , Células A549 , Humanos , Limite de Detecção
16.
Sensors (Basel) ; 19(5)2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30871036

RESUMO

The NASA's Earth Polychromatic Imaging Camera (EPIC) on board the Deep Space Climate Observatory (DSCOVR) satellite has been making multiple observations of the entire sunlit Earth in a given day from the Sun-Earth Largangian L1 point since the summer of 2015. EPIC contains 10 narrow channels in the 317⁻780 nm solar spectral range. The data acquired with EPIC have already been used in a variety of scientific investigations, including the study of the global ozone levels, aerosol index and aerosol optical depth, UV reflectivity of clouds over land and ocean, cloud height over land and ocean, and vegetation indices. In this article, we report that EPIC data, particularly for the data measured with narrow channels centered near 443, 551, and 680 nm, can also have important applications in remote sensing of ocean color in different geographical regions. We have modified a version of a multi-channel atmospheric correction algorithm for Moderate Resolution Imaging SpectroRadiometer (MODIS) ocean color applications and adapted the algorithm for processing EPIC data. We present three case studies on water leaving reflectance retrievals from EPIC data acquired over a large turbid river, inland lakes, and oceans. We conclude that a future ocean color instrument on board a satellite at the L1 point, which provides continuous view of the full sunlit disk of the Earth, will complement and extend ocean color observations with the low Earth observing polar orbital and geostationary satellite instruments in both the spatial and time domains.

17.
Molecules ; 24(10)2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31108858

RESUMO

(1) Background: Rhubarb anthraquinones-a class of components with neuroprotective function-can be used to alleviate cerebral ischemia reperfusion injury. (2) Methods: The three pharmacodynamic indicators are neurological function score, brain water content, and cerebral infarction area; UPLC-MS/MS was used in pharmacokinetic studies to detect plasma concentrations at different time points, and DAS software was used to calculate pharmacokinetic parameters in a noncompartmental model. (3) Results: The results showed that the pharmacodynamics and pharmacokinetics of one of the five anthraquinone aglycones could be modified by the other four anthraquinones, and the degree of interaction between different anthraquinones was different. The chrysophanol group showed the greatest reduction in pharmacodynamic indicators comparing with other four groups where the rats were administered one of the five anthraquinones, and there was no significant difference between the nimodipine group. While the Aloe-emodin + Physcion group showed the most obvious anti-ischemic effect among the groups where the subjects were administered two of the five anthraquinones simultaneously. Emodin, rhein, chrysophanol, and physcion all increase plasma exposure levels of aloe-emodin, while aloe-emodin lower their plasma exposure levels. (4) Conclusions: This experiment provides a certain preclinical basis for the study of anthraquinone aglycones against cerebral ischemia and a theoretical basis for the study of the mechanism of interaction between anthraquinones.


Assuntos
Antraquinonas/administração & dosagem , Isquemia Encefálica/tratamento farmacológico , Rheum/química , Aloe/química , Animais , Antraquinonas/química , Antraquinonas/farmacocinética , Modelos Animais de Doenças , Quimioterapia Combinada , Emodina/administração & dosagem , Emodina/análogos & derivados , Emodina/química , Emodina/farmacocinética , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/farmacocinética , Ratos
18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(2): 571-6, 2017 Feb.
Artigo em Zh | MEDLINE | ID: mdl-30291820

RESUMO

The reflectance of saline soil in the downstream of No.500 reservoir in Fukang, Xinjiang province was investigated. Through filed sampling and spectral test, using the method of spectral transform, correlation analysis and a quantitative analysis were conducted on the salt and water content of the soil under different disturbance degree. A multiple linear regression model was established between the soil reflectance and soil salinity content. The results show that: first, the human disturbance has a significantly positive correlation with the soil content while it has an extremely negative correlation with the water content. The correlation coefficients are 0.961 and -0.929 respectively. Secondly, it shows that those most heavily disturbed soil reflectance is about 10%higher than the slightly disturbed, while the slightly disturbed soil reflectance is about 17% higher than the undisturbed soil. The reason is that the soil surface of barren land with a small amount of vegetation, the biological creature and soil surface crust have been destroyed. The more the disturbance is, the greater chance the surface layer would be destroyed. Meanwhile, the surface layer of soil will be lack of the crust protective; the soil salinity of the bottom rises to the surface associated with the soil moisture will quickly evaporate. The salt is concentrated to the surface layer due to both little precipitation and a lack of protection of soil crust. Thirdly, the peak wavelength location of the spectrum is increased (999, 876~979, 1 182~1 370, 1 900 nm) while the soil is taken from undisturbed to heavily disturbed conditions, which means that with the increase of disturbance, the soil becomes more sensitive in the near infrared region. What's more, the three different prediction models are established though the reflectance R, the reflectivity of the first derivative R', the reflectance R+water. According to the R(2) and the RMSE to comprehensive judge the accuracy of the model. It is found that among those established prediction models of the same soil salinity in the different levels of disturbance, the smaller the degree of human disturbance is, the higher the accuracy of model is. It is found that among all of those established prediction models, the one based on the derivative of R works the best, of which R(2) is larger than 0.983, model accuracy is improved by 5%~10% ,which means that through a derivative transformation, the linear noises in the original spectrum can be removed.

19.
J Phys Chem A ; 120(46): 9330-9340, 2016 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-27934245

RESUMO

Zwitterionic complexes have been the subject of great interest in the past several decades due to their multifunctional application in supramolecular chemistry. Herein, a series of internally stable charge-compensated carboranylated square-planar Pt(II) zwitterionic complexes have been explored by density functional theory aim to assessing their structures, the first hyperpolarizabilities, first hyperpolarizability densities, and electronic absorption spectra. It is found that the first hyperpolarizabilities of two-dimensional (2D) structure complexes are much larger with respect to the one-dimensional complex. It is ascribed to the lower transition energy and more obvious charge transfer, which can be further illustrated by their large amplitude and separate distribution of first hyperpolarizability density. In addition, the first hyperpolarizabilities of 2D complexes can be further significantly modified by introducing electron-donating/withdrawing groups on the carborane cage. As a consequence, we believe that these 2D zwitterionic complexes can behave as novel second-order nonlinear optical chromophore with a promising future.

20.
Sensors (Basel) ; 15(10): 25703-15, 2015 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-26473861

RESUMO

The Geostationary Ocean Color Imager (GOCI) is the first geostationary ocean color sensor in orbit that provides bio-optical properties from coastal and open waters around the Korean Peninsula at unprecedented temporal resolution. In this study, we compare the normalized water-leaving radiance (nLw) products generated by the Naval Research Laboratory Automated Processing System (APS) with those produced by the stand-alone software package, the GOCI Data Processing System (GDPS), developed by the Korean Ocean Research & Development Institute (KORDI). Both results are then compared to the nLw measured by the above water radiometer at the Ieodo site. This above-water radiometer is part of the Aerosol Robotic NETwork (AeroNET). The results indicate that the APS and GDPS processed  correlates well within the same image slot where the coefficient of determination (r²) is higher than 0.84 for all the bands from 412 nm to 745 nm. The agreement between APS and the AeroNET data is higher when compared to the GDPS results. The Root-Mean-Squared-Error (RMSE) between AeroNET and APS data ranges from 0.24 [mW/(cm²srµm)] at 555 nm to 0.52 [mW/(cm²srµm)]  at 412 nm while RMSE between AeroNET and GDPS data ranges from 0.47 [mW/(cm²srµm)] at 443 nm to 0.69 [mW/(cm²srµm)]  at 490 nm.


Assuntos
Monitoramento Ambiental/métodos , Sistemas de Informação Geográfica , Processamento de Imagem Assistida por Computador/métodos , Oceanos e Mares , Astronave , Cor
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