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1.
BMC Genomics ; 25(1): 260, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38454328

RESUMEN

In this study, we conducted an assembly and analysis of the organelle genomes of Aconitum carmichaelii. Our investigation encompassed the examination of organelle genome structures, gene transfer events, and the environmental selection pressures affecting A. carmichaelii. The results revealed distinct evolutionary patterns in the organelle genomes of A. carmichaelii. Especially, the plastome exhibited a more conserved structure but a higher nucleotide substitution rate (NSR), while the mitogenome displayed a more complex structure with a slower NSR. Through homology analysis, we identified several instances of unidirectional protein-coding genes (PCGs) transferring from the plastome to the mitogenome. However, we did not observe any events which genes moved from the mitogenome to the plastome. Additionally, we observed multiple transposable element (TE) fragments in the organelle genomes, with both organelles showing different preferences for the type of nuclear TE insertion. Divergence time estimation suggested that rapid differentiation occurred in Aconitum species approximately 7.96 million years ago (Mya). This divergence might be associated with the reduction in CO2 levels and the significant uplift of the Qinghai-Tibet Plateau (QTP) during the late Miocene. Selection pressure analysis indicated that the dN/dS values of both organelles were less than 1, suggested that organelle PCGs were subject to purification selection. However, we did not detect any positively selected genes (PSGs) in Subg. Aconitum and Subg. Lycoctonum. This observation further supports the idea that stronger negative selection pressure on organelle genes in Aconitum results in a more conserved amino acid sequence. In conclusion, this study contributes to a deeper understanding of organelle evolution in Aconitum species and provides a foundation for future research on the genetic mechanisms underlying the structure and function of the Aconitum plastome and mitogenome.


Asunto(s)
Aconitum , Filogenia , Aconitum/genética , Aconitum/química , Aconitum/metabolismo , Orgánulos/genética , Tibet
2.
Front Psychiatry ; 14: 1199408, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37520234

RESUMEN

Background: Globally, the coronavirus disease 2019 (COVID-19) pandemic has negatively affected mental health services, but there is no clear evidence of this in China. Therefore, we examined the effect of the COVID-19 pandemic on the use of serious mental illness (SMI)-related outpatient services in Ningbo, China. Methods: We analyzed the trends in monthly SMI-related outpatient department utilization from January 2018 to June 2022 using interrupted time series (ITS) regression analysis, and we defined the onset of the COVID-19 pandemic as January 2020. We also performed ITS regression analyses for sex and age subgroups. Results: A significant difference in the monthly number of outpatient visit slopes before and after the onset of the pandemic was shown in the SMI analysis [-175.6, 95% confidence interval (CI) (-338.3 to -12.9), p < 0.05]. All sex and age categories, except the 20-30 years age category, showed statistically significant changes in their slopes after the onset of the pandemic. Significant differences in the number of outpatient visit slopes before and after the onset of the pandemic were seen for schizophrenia and bipolar disorders [-153.3, 95% CI (-294.1 to -12.5) and -16.8 (-31.0 to -2.6), respectively]. Moreover, a negative relationship was observed between the monthly number of outpatient visits and the number of incidents and accidents due to SMI (r = -0.38, p < 0.05). Conclusion: The COVID-19 pandemic has had a negative effect on SMI-related outpatient visits in Ningbo, especially by patients with schizophrenia. A strategy should be developed and implemented to maintain access to SMI services during the COVID-19 pandemic.

3.
Phys Chem Chem Phys ; 25(13): 9158-9167, 2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-36942943

RESUMEN

Owing to some special superiority, luminescence ratiometric thermometry, mainly including dual excitations single emission and single excitation dual emissions, has gained popularity over the past few years. However, developing novel ratiometric thermometry that can work in multi-mode is still a challenge. Here we report a temperature measurement method based on the photoinduced luminescence of Tb3+ in the low-cost and easy to prepare calcium tungstate. Both the conventional luminescence intensity ratio (LIR) and recently developed single-band ratiometric (SBR) strategies have been achieved in our materials. On the one hand, upon excitation of the charge transfer state, the emissions from the excited 5D4 and 5D3 states present different responses to temperature. A thermometry depending on the LIR between these two emissions has thus been developed, with adjustable relative sensitivity that is sensitive to the excitation wavelength. On the other hand, both the emissions from the excited 5D4 and 5D3 states respond dissimilarly to the temperature variation. A SBR thermometer has thus been constructed with two excitation modes, reaching the maximum relative sensitivity of 1.83% K-1 at 573 K. The present work is expected to inspire other researchers to exploit more multi-mode optical ratiometric thermometries.

4.
Sensors (Basel) ; 22(21)2022 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-36365961

RESUMEN

A theoretical model for studying the temperature properties of singlemode-multimode-singlemode (SMS) fiber structure fabricated by absorptive multimode fiber (MMF) cladding is established. Moreover, an SMS-based temperature sensor is fabricated and experimentally demonstrated. Experimental results show that the dip wavelength of the transmission spectrum changes linearly with temperature, which is in good agreement with the simulated results obtained by using the model. Further, a comprehensive study of temperature characteristics affected by the thermo-optic effect, thermal expansion effect, and thermal effect of absorption characteristics is performed for SMS fiber optic structures with different refractive indexes, thermo-optic coefficients, and absorption properties of MMF cladding, MMF core diameters, and thermal expansion coefficients of packaging shell. According to the obtained rules, investigations are carried out into the thermal response of an SMS fiber structure resulting from combined thermal effects for temperature performance optimization. Excellent temperature stability with a temperature sensitivity of 0 pm/°C or good temperature sensitivity of -441.58 pm/°C is achieved accordingly.

5.
Plant Physiol Biochem ; 170: 98-109, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34863059

RESUMEN

MYB proteins play a crucial role in plant growth and development and stress responses. In this study, 160 members of the MYB gene family from the pepper genome database were used to analyze gene structures, chromosome localization, collinearity, genetic affinity and expression in response to heavy metals. The results identified R2R3-MYB members and further phylogenetically classified them into 35 subgroups based on highly conserved gene structures and motifs. Collinearity analysis showed that segmental duplication events played a crucial role in the functional expansion of the CaMYB gene family by intraspecific collinearity, and at least 12 pairs of CaMYB genes existed between species prior to the differentiation between monocots and dicots. Moreover, the upstream CaMYB genes were mainly localized to the phytohormone elements ABRE and transcription factor elements MYB and MYC. Further analysis revealed that MYB transcription factors were closely associated with a variety of abiotic stress-related proteins (e.g., MAC-complex and SKIP). Under the stress of five metal ions, Cd2+, Cu2+, Pb2+, Zn2+, and Fe3+, the expression levels of some CaMYB family genes were upregulated. Of these genes, pairing homologous 1 (PH-1), PH-13, and PH-15 in the roots of Capsicum annuum were upregulated to the greatest extent, indicating that these three MYB family members are particularly sensitive to these five metals. This study provides a theoretical reference for the analysis of the molecular regulatory mechanism of MYB family genes in mediating the response to heavy metals in plants. This study reveals the mode of interaction between MYB and a variety of abiotic stress proteins and clarifies the biological functions of CaMYB family members in the regulation of heavy metal stress.


Asunto(s)
Capsicum , Metales Pesados , Capsicum/genética , Capsicum/metabolismo , Regulación de la Expresión Génica de las Plantas , Metales Pesados/toxicidad , Familia de Multigenes , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
6.
Environ Pollut ; 247: 285-292, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30685669

RESUMEN

Previous studies found that mental disorders such as bipolar disorder, seasonal affective disorder and schizophrenia, often show seasonal variability, which usually be attributed to the variations in the number of natural sunlight. However, few studies have been conducted on the acute effects of exposure to sunlight on the onset of these disease. The aim of this study was to evaluate the exposure-response relationship between sunshine duration and the hospital admissions for schizophrenia. We obtained data on hospital admissions for schizophrenia from the largest psychiatric hospital in Ningbo, China, during 2012-2016. A Distributed lag non-linear model was used to estimate the exposure-lag-response relationship between sunlight and schizophrenia. We calculated the effects of short and long sunshine duration, defined using the cutoffs at the 1st and 99th sunshine duration percentiles. We detected significant and non-linear associations between sunlight and schizophrenia, and the overall estimated relative risk (RR) for a lag of 0-21 days was 1.45 (95% CI: 1.07, 1.97) and 1.41(95% CI: 0.72, 2.75) for short and long sunshine duration, respectively. The burden of schizophrenia was greater during periods with short sunshine duration than during periods with long sunshine duration, with the AFs of 19.94% (95% CI: 8.65%, 28.24%) and 2.12% (95% CI: -2.70%, 5.57%), respectively. The female and people more than 45 years old were most susceptible to these effects. We repeated our analysis by using global solar radiation as a continuous exposure variable of sunlight intensity in the model, and the result shows that the female and middle-aged and eldly patients were also susceptible to the effects of low levels of global solar radiation. Our findings suggest that there may be a relationship between lack of exposure to sunlight and increased risk of hospital admissions for schizophrenia. Policymakers and doctors should promote further understanding of the health benefits of sunlight and take effective measures to prevent schizophrenia.


Asunto(s)
Exposición a Riesgos Ambientales/estadística & datos numéricos , Esquizofrenia/epidemiología , Luz Solar , Adulto , China/epidemiología , Femenino , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Riesgo , Estaciones del Año , Factores de Tiempo
7.
Oncol Lett ; 16(4): 4821-4828, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30250547

RESUMEN

Cisplatin-based chemotherapy is commonly used for the clinical treatment of patients with non-small cell lung cancer (NSCLC). However, the anti-tumor efficacy of cisplatin is limited by poor clinical response and the development of chemoresistance. At present, the underlying mechanism for cisplatin resistance remains unclear. In the present study, it was identified that metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), a long non-coding RNA that has been demonstrated to function as an oncogene, was increased in tumor tissues from patients with cisplatin-resistant NSCLC. In addition, the MALAT1 level was increased in A549rCDDP cells compared with the parental A549 cells. Silencing of MALAT1 sensitized A549rCDDP cells to cisplatin treatment, while overexpression of MALAT1 in A549 cells decreased their sensitivity towards cisplatin. Through analysis of the gene expression in patient samples, a decrease in miR-145 and an increase in Kruppel-like factor 4 (KLF4) in tumor tissues compared with adjacent normal tissues was observed. A negative association between MALAT1 and miR-145 was also identified in A549 cells and A549rCDDP cells. Furthermore, reverse transcription quantitative polymerase chain reaction and western blotting identified that KLF4 was positively and negatively regulated by MALAT1 and miR-145, respectively. The direct regulatory association between MALAT1 and miR-145 and the target gene KLF4 was additionally confirmed using a luciferase reporter assay. Knockdown of MALAT1 reversed cisplatin resistance in A549rCDDP cells. Taken together, these data indicated that MALAT1 decreased the sensitivity of NSCLC to cisplatin via the regulation of miR-145 and KLF4.

8.
Genes (Basel) ; 8(7)2017 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-28726715

RESUMEN

Inositol is a cyclic polyol that is involved in various physiological processes, including signal transduction and stress adaptation in plants. l-myo-inositol monophosphatase (IMPase) is one of the metal-dependent phosphatase family members and catalyzes the last reaction step of biosynthesis of inositol. Although increased IMPase activity induced by abiotic stress has been reported in chickpea plants, the role and regulation of the IMP gene in rice (Oryza sativa L.) remains poorly understood. In the present work, we obtained a full-length cDNA sequence coding IMPase in the cold tolerant rice landraces in Gaogonggui, which is named as OsIMP. Multiple alignment results have displayed that this sequence has characteristic signature motifs and conserved enzyme active sites of the phosphatase super family. Phylogenetic analysis showed that IMPase is most closely related to that of the wild rice Oryza brachyantha, while transcript analysis revealed that the expression of the OsIMP is significantly induced by cold stress and exogenous abscisic acid (ABA) treatment. Meanwhile, we cloned the 5' flanking promoter sequence of the OsIMP gene and identified several important cis-acting elements, such as LTR (low-temperature responsiveness), TCA-element (salicylic acid responsiveness), ABRE-element (abscisic acid responsiveness), GARE-motif (gibberellin responsive), MBS (MYB Binding Site) and other cis-acting elements related to defense and stress responsiveness. To further investigate the potential function of the OsIMP gene, we generated transgenic tobacco plants overexpressing the OsIMP gene and the cold tolerance test indicated that these transgenic tobacco plants exhibit improved cold tolerance. Furthermore, transgenic tobacco plants have a lower level of hydrogen peroxide (H2O2) and malondialdehyde (MDA), and a higher content of total chlorophyll as well as increased antioxidant enzyme activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD), when compared to wild type (WT) tobacco plants under normal and cold stress conditions.

9.
Opt Express ; 24(10): 10946-55, 2016 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-27409916

RESUMEN

We investigate ultra-broadband wavelength converters based on cascaded second-harmonic generation and difference frequency generation using Bessel-chirped gratings (BCGs) in lithium niobate waveguides, and compare them to the ones using uniform grating and segmented grating, respectively. For the same length and power, the BCGs show broader bandwidth than the other two types of grating. The ripple of the matching response is very small as well. Analysis also shows that almost the same conversion bandwidth and maximum conversion efficiency with tolerant response flatness can be achieved when the manufacturing tolerance of the waveguide length is smaller than 0.1 cm.

10.
Rev Sci Instrum ; 86(1): 013108, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25638073

RESUMEN

The temperature cross-sensitivity characteristics of a singlemode-multimode-singlemode (SMS) fiber structure packaged by a shell are studied both theoretically and experimentally. By theoretical investigation, we found that the temperature sensitivity of a SMS structure is mainly determined by the thermo-optic effect (TOE) of the cladding of the multimode fiber (MMF). Meanwhile, the TOE of the MMF core, thermal expansion effects (TEEs) of the MMF core, and the packaging material also influence the ultimate sensitivity, and the magnitude of their effects depends on the refractive index of the MMF cladding. Among them, the TEE of the packaging material, inducing an axial strain, is considered to be the second main factor. A temperature sensor based on a packaged SMS structure is designed and investigated to experimentally verify the theoretical findings. The experimentally measured temperature sensitivity of the sensor is -453.4 pm/°C, which agrees well with the theoretical prediction.

11.
Rev Sci Instrum ; 85(8): 083107, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25173246

RESUMEN

A reflective all-fiber current sensor based on magnetic fluid (MF) is reported. The MF is used as the cladding of a piece of no-core fiber which is spliced between two sections of singlemode fiber to form a singlemode-multimode-singlemode structure. An intensity based interrogation scheme with a superluminescent diode as the light source and the dual-balanced detection method is used in the sensing system. The influence of the direction of the magnetic field on the sensitivity of the sensor is also experimentally investigated and analyzed.

12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(10): 1965-7, 2006 Oct.
Artículo en Chino | MEDLINE | ID: mdl-17205764

RESUMEN

The silver chloride microcrystals emulsion which are sensitized by the adsorbed green-sensitive cyanine dye of different concentration, was studied by using the absorption spectrum. The experiments show that when the sensitizing concentration is less than 0.02 mL (5.0 mg x mL(-1))/40 g emulsion, the dye J-aggregate is not formed on the surface of silver chloride microcrystals; when the dye concentration is more than 0.2 mL (5.0 mg x mL(-1)/40 g emulsion, the dye J-aggregate is formed on the surface of silver chloride microcrystals; compare to the M-state of dye, the maximal absorption peak of J-aggregate shifted to a longer wavelength by about 50 nm. It was found, when the J-aggregate is formed, the absorption in the wavelength range of more than 450 nm is increased.

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