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1.
Sci Total Environ ; 933: 173125, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38734095

RESUMO

The abuse of antibiotics has caused the accumulation of antibiotic residues in environmental media, threatening the ecosystem and human health. Many studies on the distribution of aqueous antibiotics have been reported. However, the pollution status of antibiotics in the environment in Chinese herbal medicine planting areas is rarely comprehensively clarified, resulting in the lack of updated pollution data and conducive suggestions for ecological cultivation and sustainable development of Chinese herbal medicine. Thus, we comprehensively investigated the distribution, profiles, sources, and risks of the antibiotics in the surface water of an important tributary of the Huaihe River Basin, located in Bozhou City, a significant Chinese herbal medicine planting region. Solid-phase extraction coupled with an ultra-performance liquid chromatography-tandem mass spectrometer (SPE-UPLC-MS) was utilized to detect the antibiotics in the water. 27 kinds of antibiotics were identified with total concentrations ranging from 75.01 to 1737.99 ng·L-1, with doxycycline (DC) and doxycycline hydrochloride (DCH) possessed the highest concentration. And DC, DCH, oxilinic acid (OA), sulfamethoxazole (SMZ), clarithromycin (CLA), and roxithromycinum (ROX) were the main antibiotics detected in this basin. Correlation analysis and principal component analysis (PCA) indicated that animal husbandry was the primary source of antibiotics. Furthermore, the ecological risk assessment revealed that certain antibiotics could seriously threaten the survival of aquatic organisms, implying that local Chinese herbal medicines might be at similar growth risk. The drinking risk assessment showed that antibiotics in the water posed low risks for human, and children faced a greater drinking risk than adults. The study can help to facilitate the management of aqueous antibiotic pollution for the ecological cultivation and safe production of Chinese herbal medicine.


Assuntos
Antibacterianos , Monitoramento Ambiental , Rios , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Antibacterianos/análise , Rios/química , China , Medicamentos de Ervas Chinesas
2.
Int J Biol Macromol ; 269(Pt 2): 131803, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38670205

RESUMO

Melatonin plays an important role in mammalian reproductive activities, to further understand the effects of endogenous melatonin on functions of ovary, the transgenic sheep with overexpression of melatonin synthetic enzyme gene ASMT in ovary were generated. The results showed that total melatonin content in follicular fluid of transgenic sheep was significantly greater than that in the wild type. Accordingly, the follicle numbers of transgenic sheep were also significantly greater than those in the WT. The results of follicular fluid metabolites sequencing showed that compared with WT, the differential metabolites of the transgenic sheep were significantly enriched in several signaling pathways, the largest number of metabolites was lipid metabolism pathway and the main differential metabolites were lipids and lipoid molecules. SMART-seq2 were used to analyze the oocytes and granulosa cells of transgenic sheep and WT sheep. The main differential enrichment pathway was metabolic pathway, in which lipid metabolism genes accounted for the majority. In conclusion, this is the first report to show that ovary overexpression of ASMT increased local melatonin production and follicle numbers. These results may imply that ASMT plays an important role in follicle development and formation, and melatonin intervention may be a potential method to promote this process.


Assuntos
Animais Geneticamente Modificados , Metabolismo dos Lipídeos , Melatonina , Folículo Ovariano , Animais , Feminino , Metabolismo dos Lipídeos/genética , Ovinos , Folículo Ovariano/metabolismo , Melatonina/metabolismo , Ovário/metabolismo , Líquido Folicular/metabolismo , Arilalquilamina N-Acetiltransferase/genética , Arilalquilamina N-Acetiltransferase/metabolismo , Oócitos/metabolismo , Células da Granulosa/metabolismo
3.
J Anim Sci Biotechnol ; 13(1): 145, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36434676

RESUMO

BACKGROUND: SCNT (somatic cell nuclear transfer) is of great significance to biological research and also to the livestock breeding. However, the survival rate of the SCNT cloned animals is relatively low compared to other transgenic methods. This indicates the potential epigenetic variations between them. DNA methylation is a key marker of mammalian epigenetics and its alterations will lead to phenotypic differences. In this study, ASMT (acetylserotonin-O-methyltransferase) ovarian overexpression transgenic goat was produced by using SCNT. To investigate whether there are epigenetic differences between cloned and WT (wild type) goats, WGBS (whole-genome bisulfite sequencing) was used to measure the whole-genome methylation of these animals. RESULTS: It is observed that the different mCpG sites are mainly present in the intergenic and intronic regions between cloned and WT animals, and their CG-type methylation sites are strongly correlated. DMR (differentially methylated region) lengths are located around 1000 bp, mainly distributed in the exonic, intergenic and intronic functional domains. A total of 56 and 36 DMGs (differentially methylated genes) were identified by GO and KEGG databases, respectively. Functional annotation showed that DMGs were enriched in biological-process, cellular-component, molecular-function and other signaling pathways. A total of 10 identical genes related to growth and development were identified in GO and KEGG databases. CONCLUSION: The differences in methylation genes among the tested animals have been identified. A total of 10 DMGs associated with growth and development were identified between cloned and WT animals. The results indicate that the differential patterns of DNA methylation between the cloned and WT goats are probably caused by the SCNT. These novel observations will help us to further identify the unveiled mechanisms of somatic cell cloning technology, particularly in goats.

4.
Molecules ; 27(2)2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35056885

RESUMO

BACKGROUND: Transgenic animal production is an important means of livestock breeding and can be used to model pharmaceutical applications. METHODS: In this study, to explore the biological activity of endogenously produced melatonin, Acetylserotonin-O-methyltransferase (ASMT)-overexpressed melatonin-enriched dairy goats were successfully generated through the use of pBC1-ASMT expression vector construction and prokaryotic embryo microinjection. RESULTS: These transgenic goats have the same normal phenotype as the wild-type goats (WT). However, the melatonin levels in their blood and milk were significantly increased (p < 0.05). In addition, the quality of their milk was also improved, showing elevated protein content and a reduced somatic cell number compared to the WT goats. No significant changes were detected in the intestinal microbiota patterns between groups. When the animals were challenged by the intravenous injection of E. coli, the ASMT-overexpressed goats had a lower level of pro-inflammatory cytokines and higher anti-inflammatory cytokines compared to the WT goats. Metabolic analysis uncovered a unique arachidonic acid metabolism pattern in transgenic goats. CONCLUSIONS: The increased melatonin production due to ASMT overexpression in the transgenic goats may have contributed to their improved milk quality and enhanced the anti-inflammatory ability compared to the WT goats.


Assuntos
Acetilserotonina O-Metiltransferasa
5.
Appl Opt ; 59(17): 5247-5251, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32543545

RESUMO

Using an 8 µm long-wave infrared laser as the fundamental wave, we achieved second-harmonic generation (SHG) and sum-frequency generation simultaneously in AgGaGe5Se12 and obtained a 4 µm laser output. Among them, SHG was achieved in the 173 nm spectral range of the fundamental wave, which was consistent with theoretical calculations. The average power of the obtained 4 µm laser was 41 mW, corresponding to an optical-to-optical conversion efficiency of 3.2%. The measured temperature acceptance bandwidth (LδT) (FWHM) was 50 K·cm; the angular acceptance bandwidth (Lδθ) (FWHM) was 13.3 mrad·cm; and the average absorption coefficient in the wavelength range of 0.86-11.30 µm was 0.07cm-1. In addition, the spectral acceptance bandwidth (Lδλ) of fundamental wave in AgGaGe5Se12 SHG and the spectral gain bandwidth of frequency downconversion in AgGaGe5Se12 were calculated. In view of the small absorption coefficient, the large temperature acceptance bandwidth, and the large spectral gain bandwidth, we conclude that AgGaGe5Se12 is a suitable nonlinear crystal for high-power short/mid/long-wave infrared lasers and frequency conversions of nanosecond-femtosecond infrared lasers. These results are conducive to the further development of AgGaGe5Se12 lasers.

6.
Opt Lett ; 44(9): 2201-2203, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31042183

RESUMO

A mid-infrared BaGa4Se7 optical parametric oscillator with high conversion efficiency and beam quality is demonstrated, which is pumped by a 2.79-µm electro-optically Q-switched Cr, Er:YSGG laser. A pulse energy of 3.5 mJ with a pulse width of 21 ns at 10 Hz is obtained in the range of 3.94-9.55 µm, and the beam quality factors are measured to be Mx2=5.0 and My2=4.6. The optical-to-optical conversion efficiency is 18.9%, and the slope efficiency is 31.6%, which is a 59% improvement on the best of the previously reported slope efficiencies for BaGa4Se7-based OPOs.

7.
Inorg Chem ; 57(23): 14866-14871, 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30411888

RESUMO

Recently developed chalcogenides nonlinear optical crystals have potential application in mid- to far-infrared laser fields. However, high-quality single crystals are hard to be prepared because of high vapor pressure of sulfur component and decomposition of chalcogenides during the polycrystalline synthesis and single-crystal growth. A pressure-assisted technique was performed to prepare stoichiometric AgGaS2 and AgGaGeS4 polycrystalline materials. On the basis of the synthesized polycrystalline materials, high-quality AgGaS2 and AgGaGeS4 single crystals were successfully obtained using the seed directional Bridgman method with a well-designed crucible-capsule technique. These single crystals possess high homogeneity and low absorption coefficient, making it can be applied in nonlinear optical experiments. The pressure-assisted method can also be suitable to prepare other chalcogenide and phosphide compounds. The method of polycrystalline synthesis and single crystals growth described in this work will be helpful for preparing other chalcogenides nonlinear optical crystals.

8.
Opt Express ; 25(4): 3373-3380, 2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-28241551

RESUMO

We experimentally demonstrate a ZnGeP2 based optical parametric oscillator (ZGP-OPO) with a record of the optical-to-optical conversion efficiency. To improve the conversion efficiency, we design and construct a double-pass pumped high-gain OPO and a matched large-sized high-peak-power pump beam to suppress the spatial walk-off and conversion. Pulse energy of 19 mJ with pulse width of 27.8 ns at 5 Hz in the mid-infrared 3-5 µm waveband is obtained in the doubly resonated ZGP-OPO, the beam quality M2 is about 9.6, and the corresponding optical-to-optical conversion efficiency reaches up to 75.7%.

9.
Zhonghua Yi Xue Za Zhi ; 82(15): 1046-9, 2002 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-12194796

RESUMO

OBJECTIVE: To study the relationships between polymorphisms of angiotensin-converting enzyme 1 (ACE-1) gene and N(5),N(10) -methylene-tetra-hydrofolic acid reductase (MTHFR) gene and ischemic stroke (IS). METHODS: The polymorphisms of ACE-1 and MTHFR genes in the peripheral white blood cells of 143 patients with IS and 154 controls were analyzed using PCR- RFLP. RESULTS: The frequencies of II, ID, and DD genotypes of ACE-1 gene were 37.1%, 48.3%, and 14.7% respectively in IS patients,and were 44.2%, 37.7%, and 18.2% respectively in the controls. The relative risk of stroke in IS group was 1.2 times that in the control group. The frequencies of TT, CT, and CC genotypes of MTHFR gene were 14.0%; 45.5%, and 40.5% respectively in the IS group, and 5.2%, 31.8%, and 63.0% respectively in the control group. The frequency of TT genotype was 5.2% in the control group and 1.4% in the IS group (P < 0.05). The frequency of T allele was 21.10% in the control group and 36.65% in the IS group (P < 0.01). The individuals with TT + ID or CT + ID were more susceptible to IS. The individuals with TT + ID were 4.3 times susceptible to IS than the controls, and the individuals with CT + ID were 1.63 times susceptible to IS than the controls. However, the individuals with CC + ID were less susceptable to IS in comparison to the controls (P = 0.003). CONCLUSION: TT and CT genotypes of MTHFR gene may be the risk factors of IS. There is a co-effective action between polymorphisms of ACE-1 gene and those of MTHFR gene in the pathogenesis of IS. CC genotype may have a protective effect against IS.


Assuntos
Isquemia Encefálica/genética , Predisposição Genética para Doença , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/genética , Peptidil Dipeptidase A/genética , Polimorfismo Genético , Acidente Vascular Cerebral/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2) , Pessoa de Meia-Idade , Fatores de Risco
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