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1.
Ecotoxicol Environ Saf ; 209: 111773, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33340953

RESUMO

Cadmium (Cd) is a highly toxic heavy metal that occurs widely in the environment and poses extensive threats to human health, animals, and plants. This study aims to identify and apportion multi-source and multi-phase Cd pollution from natural and anthropogenic inputs using ensemble models that include random forest (RF) in agricultural soils on Karst areas. The contributions of natural and anthropogenic factors to Cd accumulation were quantitatively assessed using the RF machine learning method. The results revealed that the main influencing factors were pH, organic carbon (Corg), and elevation. Moreover, the interaction effects of pH and Corg on distance and elevation were also quantified and visualised. It is observed that pH and Corg had stronger effects on soil Cd concentration than that of distance when pH > 7.02 and Corg > 1.53. In other words, higher Cd content in the soil along roadways may be caused by the interaction of distance, pH and Corg, with pH and Corg playing the dominant role in our case. Moreover, the maximum contribution of a single factor, elevation, to Cd concentration was about 0.13 mg/kg, and its interactions reached 1.082 mg/kg and 0.83 mg/kg, respectively, when combined with pH and Corg at 194.0 m. However, with increasing elevation, pH and Corg gradually took over the leading roles. This result not only gives us a quantitative understanding of the relationship between the factors that affect soil cadmium accumulation, but also provides an accurate method for source apportionment of heavy metals in soil.


Assuntos
Cádmio/análise , Monitoramento Ambiental/métodos , Poluição Ambiental/estatística & dados numéricos , Poluentes do Solo/análise , Agricultura , Carbonato de Cálcio , China , Poluição Ambiental/análise , Humanos , Metais Pesados/análise , Solo/química
2.
Reproduction ; 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33258800

RESUMO

Polycystic ovary syndrome (PCOS) is a common endocrine disorder accompanied by chronic low-grade inflammation; its etiology is still undefined. This study investigated the expression of CXCL12, CXCR4, and CXCR7 in PCOS rats and their role in regulation of apoptosis. To accomplish this, we established an in vivo PCOS rat model and studied KGN cells (human ovarian granulosa cell line) in vitro. In PCOS rats, the ovarian expression of CXCL12, CXCR4, and CXCR7 was reduced, and the apoptosis rate of granulosa cells was increased, accompanied by decreased expression of BCL2 and increased expression of BAX and cleaved CASPASE3 (CASP3). We further showed that recombinant human CXCL12 treatment upregulated BCL2, downregulated BAX, and cleaved CASP3 in KGN cells to inhibit their apoptosis in a concentration-dependent manner; moreover, the effect of CXCL12 was weakened by CXCR4 antagonist AMD3100 and anti-CXCR7 neutralizing antibody. In conclusion, PCOS rats showed decreased CXCL12, CXCR4, and CXCR7 expression and increased apoptosis rate of ovarian granulosa cells. Further, in human KGN cells, CXCL12 regulated the expression of BAX, BCL2, and cleaved CASP3 to inhibit apoptosis through CXCR4- and CXCR7-mediated signal transmission. These findings may provide a theoretical and practical basis for illuminating the role of proinflammatory cytokines in the pathogenesis of PCOS.

3.
Am J Clin Nutr ; 2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33381807

RESUMO

BACKGROUND: Although adherence to healthful dietary patterns has been associated with a lower risk of kidney function decline in Western populations, evidence in Asian populations remains scanty. OBJECTIVES: We examined predefined dietary patterns, namely, the Alternate Healthy Eating Index-2010 (AHEI-2010), the Dietary Approaches to Stop Hypertension (DASH), and the alternate Mediterranean diet (aMED), in relation to risk of end-stage kidney disease (ESKD). METHODS: We included 56,985 Chinese adults (aged 45-74 y) in the Singapore Chinese Health Study who were free of cancer, stroke, coronary artery disease, and ESKD at recruitment (1993-1998). Dietary pattern scores were calculated based on a validated 165-item FFQ. AHEI-2010 and aMED scores were modified by excluding the alcohol intake component because daily drinking has been associated with a higher risk of ESKD in our study population. We identified 1026 ESKD cases over a median follow-up of 17.5 y via linkage with the nationwide Singapore Renal Registry. Multivariable Cox regression models were used to compute HRs and their 95% CIs. RESULTS: Higher scores of all 3 dietary patterns were associated with lower ESKD risk in a dose-dependent manner. Compared with the lowest quintiles, the multivariable-adjusted HRs (95% CIs) of ESKD were 0.75 (0.61, 0.92) for the highest quintile of AHEI-2010, 0.67 (0.54, 0.84) for DASH, and 0.73 (0.59, 0.91) for aMED (all P-trend ≤ 0.004). These inverse associations were stronger with increasing BMI (in kg/m2), and the HRs for the diet-ESKD association were lowest in the obese (BMI ≥ 27.5), followed by the overweight (BMI = 25 to <27.5) participants, compared with those in lower BMI categories; the P-interaction values between BMI and diet scores were 0.03 for AHEI-2010, 0.004 for aMED, and 0.06 for DASH. CONCLUSIONS: Adherence to healthful dietary patterns was associated with a lower ESKD risk in an Asian population, especially in overweight or obese individuals.

4.
Small ; 16(49): e2005035, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33169482

RESUMO

The rational modulation of the nontraditional intrinsic luminescence (NTIL) of nonconventional luminophores remains difficult, on account of the limited understanding on the structure-property relationships and emission mechanisms. Herein, the effective modulation of NTIL is demonstrated based on a group of nonaromatic anhydrides and imides. Mutual bridging of isolated subgroups effectively promotes intramolecular through-space conjugation (TSC), leading to red-shifted emission, enhanced efficiency, and prolonged persistent room-temperature phosphorescence (p-RTP). The substitution of heteroatoms from oxygen to nitrogen drastically changes the TSC and enhances intermolecular interactions, resulting in enhanced emission efficiency. In addition, upon freezing, compression, or embedding into polymer matrices, the emission intensity and color remain well regulated. These results shed new light on the rational modulation of the NTIL and p-RTP of nonconventional luminophores.

5.
J Mol Endocrinol ; 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33151904

RESUMO

The aberrant histone methylation patterns contribute to the pathogenesis of endometriosis (EM). Mixed lineage leukemia 1 (MLL1), a histone methyltransferase, is crucial for gene expression by catalyzing the trimethylation of histone 3 lysine 4 (H3K4me3) in gene promoter. This study aimed to explore whether MLL1 is involved in EM-related infertility. The expressions of MLL1 and H3K4me3 were analyzed in the eutopic endometria from EM women with infertility (n=22) and the normal endometria from EM-free women (n=22). Mouse EM model was established. The MLL1 and H3K4me3 expression patterns in mice endometria of early pregnancy were also investigated. Immortalized human endometrial stromal cells (iESCs) were cultured and underwent in vitro decidualization. The chromatin immunoprecipitation followed by deep sequencing (ChIP-seq) was performed to find the target gene of MLL1 during decidual process. Results showed that both MLL1 and H3K4me3 decreased in the eutopic endometrium from EM patients compared to that in the normal endometrium. During early pregnancy and the decidual process, MLL1 and H3K4me3 were significantly upregulated in stromal cells. ChIP-seq and ChIP-qPCR found that the cytochrome c oxidase subunit 4I 2 (COX4I2) was directly targeted by MLL1. The dominance of COX4I2-containing enzyme induced the expression of hypoxia-inducible factor-2α (HIF-2α), whose expression in the peri-implantation endometrium is essential for embryo implantation. Further results showed that MLL1 was directly regulated by progesterone (P4) - P4 receptors (PRs). Our study proved that MLL1 was involved in EM-related infertility, which may provide a novel approach to treat the nonreceptive endometrium in EM patients.

6.
J Assist Reprod Genet ; 37(12): 2929-2945, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33073301

RESUMO

PURPOSE: We performed a systematic review and meta-analysis of available literature to investigate the efficacy of the intracytoplasmic sperm injection (ICSI) in couples with non-male factor with respect to the clinical outcomes. METHODS: The literature search was based on EMBASE, PubMed, and the Cochrane Library. All studies published after 1992 until February 2020 and written in English addressing patients in the presence of normal semen parameters subjected to ICSI and in vitro fertilization (IVF) were eligible. Reference lists of retrieved articles were hand-searched for additional studies. The primary outcomes were fertilization rate, clinical pregnancy rate, and implantation rate; the secondary outcomes were good-quality embryo rate, miscarriage rate, and live birth rate. RESULTS: Four RCTs and twenty-two cohort studies fulfilling the inclusion criteria were included. Collectively, a meta-analysis of the outcomes in RCTs showed that compared to IVF, ICSI has no obvious advantage in fertilization rate (RR = 1.16, 95% CI: 0.83-1.62), clinical pregnancy rate (RR = 1.04, 95% CI: 0.66-1.64), implantation rate (RR = 1.12, 95% CI: 0.67-1.86), and live birth rate (RR = 1.17, 95% CI: 0.43-3.15). Pooled results of cohort studies demonstrated a statistically significant higher fertilization rate (RR = 1.16, 95% CI: 1.03-1.31) and miscarriage rate (RR = 1.04, 95% CI: 1.01-1.06) in the ICSI group; furthermore, higher clinical pregnancy rate (RR = 0.85, 95% CI: 0.77-0.94), implantation rate (RR = 0.78, 95% CI: 0.65-0.95), and live birth rate (RR = 0.86, 95% CI: 0.79-0.94) was founded in the IVF group; no statistically significant difference was observed in good-quality embryo rate (RR = 0.98, 95% CI: 0.93-1.04). CONCLUSION: ICSI has no obvious advantage in patients with normal semen parameters. Enough information is still not available to prove the efficacy of ICSI in couples with non-male factor infertility comparing to IVF.

7.
Int J Cancer ; 2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33129230

RESUMO

There is limited research on the effect of dietary quality on hepatocellular carcinoma (HCC) risk in populations with relatively high risk of HCC. Using data from Singapore Chinese Health Study, a prospective cohort study, of 63 257 Chinese aged 45 to 74, we assessed four diet-quality index (DQI) scores: the Alternative Health Eating Index-2010 (AHEI-2010), Alternate Mediterranean Diet (aMED), Dietary Approaches to Stop Hypertension (DASH) and Heathy Diet Indicator (HDI). We identified 561 incident HCC cases among the cohort participants after a mean of 17.6 years of follow-up. Cox proportional hazard regression model was used to estimate hazard ratio (HR) and 95% confidence interval (CI) for HCC in relation to these DQI scores. Unconditional logistic regression method was used to evaluate the associations between DQIs and HCC risk among a subset of individuals who tested negative for hepatitis B surface antigen (HBsAg). High scores of AHEI-2010, aMED and DASH, representing higher dietary quality, were associated with lower risk of HCC (all Ptrend < .05). Compared with the lowest quartile, HRs (95% CIs) of HCC for the highest quartile of AHEI-2010, aMED and DASH were 0.69 (0.53-0.89), 0.70 (0.52-0.95) and 0.67 (0.51-0.87), respectively. No significant association between HDI and HCC risk was observed. Among HBsAg-negative individuals, similar inverse associations were observed, and the strongest inverse association was for aMED (HRQ4vsQ1 = 0.46, 95% CI: 0.23-0.94, Ptrend = .10). These findings support the notion that adherence to a healthier diet may lower the risk of HCC, suggesting that dietary modification may be an effective approach for primary prevention of HCC.

8.
J Pharm Biomed Anal ; 191: 113638, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32980794

RESUMO

Rubiae Radix et Rhizoma (called "Qiancao", QC), the root and rhizome of Rubia cordifolia L., has been widely used in clinical practice for its excellent performance in removing blood stasis and haemostasis. However, after carbonization processing, significant changes occurred in chemical components of the charcoal of Rubiae Radix et Rhizoma (called "Qiancaotan", QCT), which enhanced the performance in haemostasis and weakened the performance in removing blood stasis in clinic. In order to study the material basis of function variation during processing, a rapid, reliable, accurate and validated UPLC-MS/MS approach was established to determine twelve quinones in QC and QCT simultaneously. Meanwhile, the antithrombotic effect of target components on zebrafish thrombus model induced by phenylhydrazine (PHZ) was investigated. Chromatographic separation was accomplished on an ACQUITY UPLC C18column with acetonitrile-water containing 0.2 % (v/v) formic acid as mobile phase, at a flow rate of 0.30 mL/min. Quantitation was performed using multiple reaction monitoring (MRM) in positive and negative ion electrospray ionization (ESI). Furthermore, the activity evaluation studies showed that the reduction of removing blood stasis effect of QCT was due to the decrease of dehydro-α-lapachone, lapachol, rubioncolin C and mollugin. This study demonstrated that the method has been successfully applied to determine the content of twelve quinones responsible for the function variation of QCT, and provided a new insight into the material basis and the effect of eliminating stasis before and after processing of QC.

9.
Dalton Trans ; 49(24): 8056-8059, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32530019

RESUMO

In this study, we present a photo-luminescence (PL) and persistent luminescence (PersL) investigation of Ca6BaP4O17:Eu2+,Tb3+ (CBPO:Eu,Tb) at high hydrostatic pressure in the range of 0-11.04 GPa. More importantly, there is a significant increase of PL intensity and extension of PersL duration time at a pressure point of ∼0.15 GPa.

10.
J Phys Chem A ; 124(20): 3984-3992, 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32242664

RESUMO

The excited state relaxation pathways of isoxazole and oxazole upon excitation with UV-light were investigated by nonadiabatic ab initio dynamics simulations and time-resolved photoelectron spectroscopy. Excitation of the bright ππ*-state of isoxazole predominantly leads to ring-opening dynamics. Both the initially excited ππ*-state and the dissociative πσ*-state offer a combined barrier-free reaction pathway, such that ring-opening, defined as a distance of more than 2 Å between two neighboring atoms, occurs within 45 fs. For oxazole, in contrast, the excited state dynamics is about twice as slow (85 fs) and the quantum yield for ring-opening is lower. This is caused by a small barrier between the ππ*-state and the πσ*-state along the reaction path, which suppresses direct ring-opening. Theoretical findings are consistent with the measured time-resolved photoelectron spectra, confirming the timescales and the quantum yields for the ring-opening channel. The results indicate that a combination of time-resolved photoelectron spectroscopy and excited state dynamics simulations can explain the dominant reaction pathways for this class of molecules. As a general rule, we suggest that the antibonding σ*-orbital located between the oxygen atom and a neighboring atom of a five-membered heterocyclic system provides a driving force for ring-opening reactions, which is modified by the presence and position of additional nitrogen atoms.

11.
JMIR Med Inform ; 8(4): e16076, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32242824

RESUMO

BACKGROUND: Real-world data (RWD) play important roles in evaluating treatment effectiveness in clinical research. In recent decades, with the development of more accurate diagnoses and better treatment options, inpatient surgery for cervical degenerative disease (CDD) has become increasingly more common, yet little is known about the variations in patient demographic characteristics associated with surgical treatment. OBJECTIVE: This study aimed to identify the characteristics of surgical patients with CDD using RWD collected from electronic medical records. METHODS: This study included 20,288 inpatient surgeries registered from January 1, 2000, to December 31, 2016, among patients aged 18 years or older, and demographic data (eg, age, sex, admission time, surgery type, treatment, discharge diagnosis, and discharge time) were collected at baseline. Regression modeling and time series analysis were conducted to analyze the trend in each variable (total number of inpatient surgeries, mean age at surgery, sex, and average length of stay). A P value <.01 was considered statistically significant. The RWD in this study were collected from the Orthopedic Department at Peking University Third Hospital, and the study was approved by the institutional review board. RESULTS: Over the last 17 years, the number of inpatient surgeries increased annually by an average of 11.13%, with some fluctuations. In total, 76.4% (15,496/20,288) of the surgeries were performed in patients with CDD aged 41 to 65 years, and there was no significant change in the mean age at surgery. More male patients were observed, and the proportions of male and female patients who underwent surgery were 64.7% (13,126/20,288) and 35.3% (7162/20,288), respectively. However, interestingly, the proportion of surgeries performed among female patients showed an increasing trend (P<.001), leading to a narrowing sex gap. The average length of stay for surgical treatment decreased from 21 days to 6 days and showed a steady decline from 2012 onward. CONCLUSIONS: The RWD showed its capability in supporting clinical research. The mean age at surgery for CDD was consistent in the real-world population, the proportion of female patients increased, and the average length of stay decreased over time. These results may be valuable to guide resource allocation for the early prevention and diagnosis, as well as surgical treatment of CDD.

12.
J Diabetes ; 12(8): 583-593, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32142209

RESUMO

BACKGROUND: The relationship between alcohol intake and end-stage kidney disease (ESKD) risk is controversial. Moreover, while evidence has shown that the relationship between alcohol and atherosclerosis may be modified by diabetes, whether this applies to ESKD is unknown. METHODS: We examined these associations in the Singapore Chinese Health Study, a prospective cohort of 63 257 adults aged 45 to 74 years. Information on alcohol intake, diet, lifestyle factors, and medical history was collected at recruitment. We identified 1217 ESKD cases via linkage with the Singapore Renal Registry after a mean follow-up of 17.5 years. Cox regression models were used to estimate hazard ratios (HRs) and 95% CI of ESKD. RESULTS: Among the participants without diabetes at baseline, monthly to weekly drinking was associated with a decreased risk of ESKD (HR 0.69; 95% CI, 0.54-0.87) compared to nondrinkers. In contrast, this association was attenuated and not significant among those with diabetes (HR 0.82; 95% CI, 0.58-1.16; Pinteraction = .19). Comparatively, alcohol intake of ≥2 drinks per day was significantly associated with an increased risk of ESKD compared to nondrinkers among those with diabetes (HR 2.00; 95% CI, 1.14-3.53) but not among those without diabetes (HR 0.91; 95% CI, 0.53-1.56; Pinteraction = .01). The risk of ESKD among those with diabetes and who also consumed ≥2 drinks per day was increased by nearly 12-fold compared to nondrinkers without diabetes (HR 11.6; 95% CI, 6.73-19.9). CONCLUSION: Low-dose drinking is associated with a reduced risk of ESKD among individuals without diabetes. However, joint exposure to heavy drinking and diabetes is associated with a substantially higher risk of ESKD.

13.
J Chem Phys ; 152(6): 064301, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32061211

RESUMO

The influence of ring-puckering on the light-induced ring-opening dynamics of heterocyclic compounds was studied on the sample 5-membered ring molecules γ-valerolactone and 5H-furan-2-one using time-resolved photoelectron spectroscopy and ab initio molecular dynamics simulations. In γ-valerolactone, ring-puckering is not a viable relaxation channel and the only available reaction pathway is ring-opening, which occurs within one vibrational period along the C-O bond. In 5H-furan-2-one, the C=C double bond in the ring allows for ring-puckering which slows down the ring-opening process by about 150 fs while only marginally reducing its quantum yield. This demonstrates that ring-puckering is an ultrafast process, which is directly accessible upon excitation and which spreads the excited state wave packet quickly enough to influence even the outcome of an otherwise expectedly direct ring-opening reaction.

14.
Nanoscale ; 12(3): 1425-1431, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31912845

RESUMO

Halide perovskites have attracted great attention owing to their outstanding performance in optoelectronic applications and solar cells. Recently, two-dimensional (2D) Cs3Sb2I9 nanocrystals (NCs) have attracted sustained interest due to their potentially useful photovoltaic behavior. However, their practical application is impeded by the large bandgap. In this study, the bandgap of 2D Cs3Sb2I9 NCs is successfully narrowed from 2.05 eV to 1.36 eV by means of a high pressure with a measurable rate of 33.7%. Optical changes of 2D Cs3Sb2I9 NCs originate from Sb-I bond contraction and I-Sb-I bond angle changes within the [SbI6]3- octahedra, which determines the overlap of orbitals. Angle dispersive synchrotron X-ray diffraction spectra and Raman spectra of Cs3Sb2I9 NCs indicate that the structural amorphization gradually begins at about 14.0 GPa and the changes are reversible once pressure is completely released. The band gap is slightly smaller after decompression than that under the initial ambient conditions, resulting from the incomplete recrystallization process. First-principles calculations further elucidate that variations in band gaps are mainly governed by the orbital interactions associated with the distortion of the Sb-I octahedral network upon compression. The research enhances the fundamental understanding of 2D Cs3Sb2I9 NCs and is expected to greatly advance the research progress of perovskites in band gap interception at high pressures. Meanwhile, this study demonstrates that pressure processing can be used as a robust strategy to improve materials-by-design in applications.

15.
Pest Manag Sci ; 76(5): 1626-1638, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31714013

RESUMO

BACKGROUND: The Apolygus lucorum is one of the most destructive insect pests in China with a wide range of host plants. Interaction of A. lucorum with surrounding environment heavily relies on chemical communication. Deorphanization of receptors involved in odors detection elevates our understanding of the olfactory system of this pest and may help to develop a chemical ecology-based control strategy. RESULTS: AlucOR80, an odorant receptor (OR) in A. lucorum was newly cloned. Gene expression analysis showed that this receptor was mainly expressed in the antennae and head of both sexes but with a male bias. The Xenopus oocytes heterologous expression system coupled with the two-electrode voltage-clamp (TEVC) recording revealed that AlucOR80 was tuned to 21 selected compounds. Furthermore, electroantennogram (EAG) tests confirmed that all 21 ligands of AlucOR80 were electrophysiologically active in antennae of both sexes. Behavioral trials in a three-cage olfactometer indicated that 16 compounds were behaviorally active, amongst which, 12 components were attractants and four components were repellents for adults of both sexes. Butyl butyrate and Dimethyl disulfide (DMDS) were the strongest attractive and repellant compounds, respectively. Importantly, we found the repellency of 1, 8-Cineole, S-(-)-cis-Verbenol and (1S)-(1)-beta-Pinene against adults of A. lucorum. CONCLUSION: Although AlucOR80 is a general OR, may play important role in the olfactory perception of A. lucorum. Screening of AlucOR80 ligands by behavioral assay provided valuable insights by which olfactory-based management approaches could be developed by utilizing the behaviorally active components as attractants or repellents. © 2019 Society of Chemical Industry.


Assuntos
Heterópteros , Animais , China , Feminino , Masculino , Óvulo , Plantas , Receptores Odorantes
16.
J Insect Physiol ; 120: 103986, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31778688

RESUMO

Traps baited with female-produced sex pheromones have been very effective in the monitoring and management of mirid bugs in numerous field trials. However, none of the target odorant receptors for sex pheromone components in Apolygus lucorum have been identified. Here, we identified one candidate sex pheromone receptor, AlucOR4, from A. lucorum. Quantitative real-time PCR (qPCR) analysis revealed that AlucOR4 was antennae-enriched and male-biased in adult A. lucorum. Xenopus oocyte expression system assays demonstrated that AlucOR4/AlucOrco was sensitive to two major sex pheromone constituents and exhibited high sensitivity to (E)-2-hexenyl butyrate (E2HB) and lower sensitivity to hexyl butyrate (HB). The expression level of target mRNA was significantly reduced (>80%) in dsAlucOR4-injected bugs after five days. The electroantennogram (EAG) responses of male antennae to E2HB and HB were also reduced significantly (~40%). Our findings suggest that AlucOR4 is essential to sex pheromone perception in A. lucorum.

17.
Angew Chem Int Ed Engl ; 59(25): 9986-9991, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31743553

RESUMO

Photoactivation in CdSe/ZnS quantum dots (QDs) on UV/Vis light exposure improves photoluminescence (PL) and photostability. However, it was not observed in fluorescent carbon quantum dots (CDs). Now, photoactivated fluorescence enhancement in fluorine and nitrogen co-doped carbon dots (F,N-doped CDs) is presented. At 1.0 atm, the fluorescence intensity of F,N-doped CDs increases with UV light irradiation (5 s-30 min), accompanied with a blue-shift of the fluorescence emission from 586 nm to 550 nm. F,N-doped CDs exhibit photoactivated fluorescence enhancement when exposed to UV under high pressure (0.1 GPa). F,N-doped CDs show reversible piezochromic behavior while applying increasing pressure (1.0 atm to 9.98 GPa), showing a pressure-triggered aggregation-induced emission in the range 1.0 atm-0.65 GPa. The photoactivated CDs with piezochromic fluorescence enhancement broadens the versatility of CDs from ambient to high-pressure conditions and enhances their anti-photobleaching.

18.
J Pharm Biomed Anal ; 179: 113028, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31835126

RESUMO

Members of the genus Rhodiola L. have been widely used in Tibetan medicines for preventing and treating acute mountain sickness (AMS) for a long time. However, the pharmacological mechanisms of these medicines in treating AMS remain unclear. To address this problem, an integrative method combining ultra-performance liquid chromatography coupled with a quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS/MS)analysis and network pharmacology was employed. First, the chemical profiles of Dazhu Hongjingtian (DZ, a Chinese medicine preparation composed of R. kirilowii (Regel) Maxim) were identified or tentatively characterized. Second, the targets of DZ were predicted using the SwissTargetPrediction and STITCH databases; the targets of AMS were also collected from the Drugbank and TTD databases. Then, networks between targets and compounds or diseases were constructed by Cytoscape 3.6.1. Third, GO and pathway enrichment analyses were performed using the Database for Annotation, Visualization and Integrated Discovery (DAVID). As a result, 40 ingredients of 53 compounds in DZ might be biologically active. These activities were related to the regulatory effects of the ingredients on 68 significant signaling pathways, such as the inflammation pathway, apoptosis pathway, HIF-1 signaling pathway, and others, by targeting 33 proteins, including PTGS2 and PTGS1, ALOX5 and ALOX15, BCL2 and BCL2L1, the protein kinase C (PKC) family and HIF1A, among others.


Assuntos
Doença da Altitude/tratamento farmacológico , Medicamentos de Ervas Chinesas/química , Rhodiola/química , Doença da Altitude/fisiopatologia , Cromatografia Líquida de Alta Pressão/métodos , Bases de Dados Factuais , Medicamentos de Ervas Chinesas/farmacologia , Espectrometria de Massas em Tandem/métodos
19.
J Ethnopharmacol ; 250: 112429, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-31812644

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Reduning injection (RDN), a patented traditional Chinese medicine, has the obvious antipyretic effect and has been widely used in China. Although some previous studies proved its antipyretic effect by animal efficacy experiment or clinical observation, its holistic mechanism in vivo was still unclear. AIM OF THE STUDY: To comprehensively elucidate the antipyretic mechanism of RDN, the investigation of fever-related potential biomarkers and metabolic pathways in the rat fever model is described in this paper. MATERIALS AND METHODS: Rat fever model was established by dry yeast. A large number of endogenous metabolites in serum and urine were detected by UPLC-Q-TOF/MS, and fever-related potential biomarkers were screened and identified by multivariate analysis and metabolite databases. The reliability and biological significance of the largely disturbed biomarkers was verified by the metabolic network and the correlation with pharmacodynamic indicators, which contained IL-1ß, IL-6, TNF-α, PGE2 and cAMP. RESULTS: The established UPLC-Q-TOF/MS analytical method afforded satisfactory results in terms of precision, repeatability and stability, which met the requirements of biological sample determination. A total of 32 potential biomarkers associated with fever were screened and identified, among which 22 species could be adjusted by RDN. The metabolism pathway analysis revealed that valine, leucine and isoleucine biosynthesis, and sphingolipid metabolism were greatly disturbed. Their biomarkers involved L-leucine, L-valine, sphinganine and phytosphingosine, all of which showed a callback trend after RDN was given. These 4 biomarkers had a certain correlation with some known fever-related small molecules and pharmacodynamic indicators, which indicated that the selected fever-related biomarkers had certain reliability and biological significance. CONCLUSIONS: RDN has a good regulation of the metabolic disorder of endogenous components in dry yeast-induced fever rats. Its antipyretic mechanism is mainly related to the regulation of amino acid, lipid and energy metabolism. The study is useful to better understand and analyze the pharmacodynamic mechanism of complex systems, such as traditional Chinese medicine.


Assuntos
Antipiréticos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Febre/sangue , Febre/urina , Redes e Vias Metabólicas/efeitos dos fármacos , Aminoácidos/metabolismo , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Biomarcadores/urina , Cromatografia Líquida de Alta Pressão , Citocinas/sangue , Dinoprostona/sangue , Metabolismo Energético/efeitos dos fármacos , Febre/metabolismo , Hipotálamo , Injeções , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Espectrometria de Massas , Metabolômica , Ratos Sprague-Dawley
20.
J Am Heart Assoc ; 8(23): e013282, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31766974

RESUMO

Background Although hypertension is an established risk factor for chronic kidney disease, less is known about the relationship of pulse pressure (PP), a measure of arterial stiffness, with chronic kidney disease. We investigated the association of systolic blood pressure (BP), diastolic BP, PP, and mean arterial pressure with the risk of end-stage renal disease (ESRD) in the prospective population-based Singapore Chinese Health Study. Methods and Results We used data from 30 636 participants who had BP measured at ages 46 to 85 years during follow-up I interviews between 1999 and 2004. Information on lifestyle factors was collected at recruitment from 1993 to 1998, and selected factors were updated at follow-up I. We identified 463 ESRD cases over an average 11.3 years of follow-up I by linkage with the nationwide Singapore Renal Registry. Cox proportional hazards regression models were used to assess the relations between different BP indexes and ESRD risk. Each BP index was positively associated with ESRD when studied individually. However, when PP was included as a covariate, systolic and diastolic BP and mean arterial pressure were no longer associated with ESRD. Conversely, PP remained significantly associated with ESRD risk in a dose-dependent manner (Ptrend<0.001) after adjusting for systolic or diastolic BP. Compared with the lowest group (<45 mm Hg) of PP, the hazard ratio was 5.25 (95% CI, 3.52-7.84) for the highest group (≥85 mm Hg). The association between hypertension and ESRD risk was attenuated and no longer significant after adjusting for PP. Conclusions Our findings provide a basis for targeting reduction of arterial stiffness to decrease ESRD risk.

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