Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
1.
Sensors (Basel) ; 22(13)2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35808350

RESUMO

In recent years, ozone pollution has been increasing in some parts of the world. In this study, we used the Beijing-Tianjin-Tangshan (BJ-TJ-TS) urban agglomeration region as a case study and used satellite remotely sensed inversion data and hourly ground monitoring observations of surface ozone concentrations, meteorological data, and other factors from 2016 to 2019 to explore the spatiotemporal dynamic characteristics of surface ozone concentration and its pollution levels. We also investigated their coupling relationships with meteorological factors, including temperature, pressure, relative humidity, wind velocity, and sunshine duration, in order to support the development of effective control measures for regional ozone pollution. The results revealed that the surface ozone concentration throughout the BJ-TJ-TS region from 2016 to 2019 exhibited an overall pattern of high values in the northwest and low values in the southeast, as well as an obvious difference between built-up and non-built-up areas (especially in Beijing). Meanwhile, a notable increasing trend of ozone levels was discovered in the BJ and TJ areas from 2016 to 2019, whereas this upward trend was not evident in the TS area. In all three areas, the highest monthly average ozone values occurred in the summer month of June, while the lowest monthly average levels occurred in the winter month of December. Their diurnal variation values reached a maximum value at approximately 3:00-4:00 p.m. and a minimum value at approximately 7:00 a.m. It is clear that high temperature, long sunshine duration, low atmospheric pressure, and weak wind velocity conditions, as well as certain relative humidity levels, readily led to high-concentration ozone pollution. Meanwhile, the daily average values of the five meteorological factors on days with Grade I and Grade II ozone pollution displayed different characteristics.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Ozônio , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Pequim , China , Monitoramento Ambiental/métodos , Conceitos Meteorológicos , Ozônio/análise , Material Particulado , Estações do Ano
2.
J Pineal Res ; 63(1)2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28273380

RESUMO

Melatonin as a potent antioxidant exhibits important nutritional and medicinal values. To produce melatonin-enriched milk will benefit the consumers. In this study, a sheep bioreactor which generates melatonin-enriched milk has been successfully developed by the technology that combined CRISPR/Cas9 system and microinjection. The AANAT and ASMT were cloned from pineal gland of Dorper sheep (Ovis aries). The in vitro studies found that AANAT and ASMT were successfully transferred to the mammary epithelial cell lines and significantly increased melatonin production in the culture medium compared to the nontransgenic cell lines. In addition, the Cas9 mRNA, sgRNA, and the linearized vectors pBC1-AANAT and pBC1-ASMT were co-injected into the cytoplasm of pronuclear embryos which were implanted into ewes by oviducts transferring. Thirty-four transgenic sheep were generated with the transgenic positive rate being roughly 35% which were identified by Southern blot and sequencing. Seven carried transgenic AANAT, two carried ASMT, and 25 carried both of AANAT and ASMT genes. RT-PCR and Western blot demonstrated that the lambs expressed these genes in their mammary epithelial cells and these animals produced melatonin-enriched milk. This is the first report to show a functional AANAT and ASMT transgenic animal model which produce significantly high levels of melatonin milk compared to their wild-type counterparts. The advanced technologies used in the study laid a foundation for generating large transgenic livestock, for example, the cows, which can produce high level of melatonin milk.


Assuntos
Acetilserotonina O-Metiltransferasa/genética , Arilalquilamina N-Acetiltransferase/genética , Sistemas CRISPR-Cas/genética , Glândulas Mamárias Animais/metabolismo , Melatonina/metabolismo , Ovinos/metabolismo , Acetilserotonina O-Metiltransferasa/metabolismo , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/metabolismo , Arilalquilamina N-Acetiltransferase/metabolismo , Clonagem Molecular , Feminino , Melatonina/análise , Melatonina/química , Melatonina/genética , Leite/química , Leite/metabolismo , Ovinos/genética
3.
Sensors (Basel) ; 16(4)2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27104536

RESUMO

Multiple cropping provides China with a very important system of intensive cultivation, and can effectively enhance the efficiency of farmland use while improving regional food production and security. A multiple cropping index (MCI), which represents the intensity of multiple cropping and reflects the effects of climate change on agricultural production and cropping systems, often serves as a useful parameter. Therefore, monitoring the dynamic changes in the MCI of farmland over a large area using remote sensing data is essential. For this purpose, nearly 30 years of MCIs related to dry land in the North China Plain (NCP) were efficiently extracted from remotely sensed leaf area index (LAI) data from the Global LAnd Surface Satellite (GLASS). Next, the characteristics of the spatial-temporal change in MCI were analyzed. First, 2162 typical arable sample sites were selected based on a gridded spatial sampling strategy, and then the LAI information was extracted from the samples. Second, the Savizky-Golay filter was used to smooth the LAI time-series data of the samples, and then the MCIs of the samples were obtained using a second-order difference algorithm. Finally, the geo-statistical Kriging method was employed to map the spatial distribution of the MCIs and to obtain a time-series dataset of the MCIs of dry land over the NCP. The results showed that all of the MCIs in the NCP showed an increasing trend over the entire study period and increased most rapidly from 1982 to 2002. Spatially, MCIs decreased from south to north; also, high MCIs were mainly concentrated in the relatively flat areas. In addition, the partial spatial changes of MCIs had clear geographical characteristics, with the largest change in Henan Province.


Assuntos
Agricultura , Monitoramento Ambiental , Sistemas de Informação Geográfica , Tecnologia de Sensoriamento Remoto , China , Mudança Climática , Ecossistema , Humanos , Folhas de Planta/crescimento & desenvolvimento
4.
Nucl Med Commun ; 44(8): 732-740, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37272287

RESUMO

OBJECTIVE: To investigate the value of 18 F-fluorodeoxyglucose(FDG) PET/CT multi-time points imaging (MTPI) on the differential diagnosis between lung cancer (LC) and tuberculosis (TB). METHODS: Sixty-four patients underwent 18 F-FDG PET/CT MTPI. The stdSUVmax, stdSUVavg, retention index, metabolic tumor volume, total lesion glycolysis at four-time points and slope of metabolic curve were measured and calculated, and the sex, age, and uniformity of FDG uptake were recorded. The difference in each index between LC and TB was analyzed, and dynamic metabolic curves (DMCs) of LC and TB were fitted by significance indexes. Artificial neural network (ANN) prediction models were established between squamous cell carcinoma (SCC) and TB, as well as between adenocarcinomas and TB. RESULTS: Differences between SCC and TB, stdSUVmax/avg at four-time points, total lesion glycolysis, stdSUVmax/avg slope (1-2 h,1-3 h and 1-4 h), uniformity of FDG uptake and age were significant. stdSUVavg has the largest area under the 4 h curve; age was only significant between adenocarcinomas and TB. DMCs at 1-4 h fitted by stdSUVavg were more helpful in differentiating LC and TB than stdSUVmax. stdSUVavg(1 h and 4 h), stdSUVavg slope 1-4 h, age, and uniformity of FDG uptake were selected to establish an ANN prediction model between SCC and TB; the area under the curve (AUC) was 100.0%. The same indices were used to establish the prediction model between adenocarcinomas and TB; the AUC was up to 83.5, and after adding stdSUVavg (2 and 4 h) to adenocarcinomas and TB models, the AUC was 87.7%. CONCLUSION: 18 F-FDG PET/CT MTPI fitting DMCs and establishing an ANN prediction model would distinguish SCC from TB relatively accurately and provide certain help in the differentiation between adenocarcinomas and TB.


Assuntos
Adenocarcinoma , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Tuberculose , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Fluordesoxiglucose F18 , Diagnóstico Diferencial , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Tuberculose/diagnóstico por imagem , Carcinoma de Células Escamosas/diagnóstico por imagem , Estudos Retrospectivos , Compostos Radiofarmacêuticos
5.
Ann Nucl Med ; 36(8): 710-716, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35729486

RESUMO

OBJECTIVE: To analyze the characteristics of blood flow perfusion images at different injection levels to establish an evaluation standard for renal dynamic imaging injection quality and reduce misdiagnosis. METHODS: Data from 140 single-photon emission computed tomography renal dynamic imaging, collected in our hospital, were retrospectively analyzed. The scans were divided into four groups according to the injection quality: total leakage of the imaging agent (group A), partial leakage (group B), poor bolus injection quality (group C), and good bolus injection quality (group D). The time of appearance and regression of the pulmonary blood perfusion phase, the peak time in the abdominal aorta, and the ratio between peak count and actual drug injection count were analyzed. The renal dynamic imaging was repeated in low-quality examinations, and the comparison between the two exams provided the misdiagnosis rate caused by inadequate injections. RESULTS: The images of the lungs and abdominal aorta in group A were blurred and indistinguishable; thus, these exams were unreliable. Both appearance and fading time of the bilateral lung shadows were significantly different between groups B, C, and D (p = 0.002 and p = 0.003, respectively). The peak time and peak counting ratio in the abdominal aorta were also significantly different between these groups (p = 0.002 and p < 0.001, respectively). The misdiagnosis rates of renal dynamic imaging in groups A, B, and C due to the different injection levels were significantly different at 94.29%, 77.14%, and 18.29%, respectively. CONCLUSIONS: The times of appearance and regression of the lung shadows and the peak time and peak count ratio in the abdominal aorta in the dynamic renal imaging perfusion phase can help assess the imaging agent injection quality and identify the need for a repeated examination. Improving the imaging agent injection quality can effectively reduce the renal function misdiagnosis rate.


Assuntos
Aorta Abdominal , Meios de Contraste , Aorta Abdominal/diagnóstico por imagem , Humanos , Rim/diagnóstico por imagem , Rim/fisiologia , Pulmão/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada de Emissão de Fóton Único
6.
Ying Yong Sheng Tai Xue Bao ; 32(7): 2565-2577, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34313075

RESUMO

Atmospheric aerosols, i.e., suspension of liquid and/or solid particles in air, have serious impacts on human health. Exploring the variation and patterns of regional atmospheric aerosols is of great significance to monitor and evaluate atmosphere quality, especially in urban areas with large population. Here, with nine typical pivotal cities along the 21st Century Maritime Silk Road through Southeast Asia, South Asia to West Asia as case studies, based on MCD19A2 550 nm AOD products, combined meteorological factors, land use data, and nighttime light data, we analyzed the spatio-temporal distribution, variation features, influencing and/or driving factors of aerosols in developed urban areas over Asia. The results showed that the descending sequence of the annual aerosol optical depth (AOD) of the nine cities was Karachi, Doha, Chittagong, Bangkok, Colombo, Ho Chi Minh, Singapore, Gwadar, and Yangon during 2013-2018. Due to the influence of regional climate system and atmospheric aerosol types, the time series of annual, seasonal, and monthly AODs were significantly different. The high values of AODs in most cities were mainly located in the urban center or rapid socio-economic (e.g., industrial and agricultural) development regions. The effects of different meteorological factors on the AODs varied in different cities. The rainfall, relative humidity, and wind speed had great impacts on AODs in Ho Chi Minh, Bangkok, Singapore, and Yangon. Temperature, relative humidity, and wind speed had close correlations with AODs in Chittagong, Colombo, Karachi, and Gwadar of South Asia and Doha in West Asia. The urban area's AOD was influenced by the combined and synergistic effects of socio-economy, urbanization, and meteorological factors, with that in Karachi being the most significant.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Aerossóis/análise , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Bangladesh , Cidades , Monitoramento Ambiental , Singapura , Tailândia
7.
Fa Yi Xue Za Zhi ; 22(4): 275-6, 2006 Aug 15.
Artigo em Zh | MEDLINE | ID: mdl-17080666

RESUMO

OBJECTIVE: To improve the correct rate of ABO genotyping by meliorating AS-PCR primer. METHODS: The primer P1 was changed into primer P1' by substituting the fifth base G for C of 3' end and the ABO genotyping results of primer P1 and P1' was compared and analysed. RESULTS: The non-specific product of OO typing is reducing and the wrong genotyping of OO and AO was avoided by meliorating AS-PCR primer. CONCLUSION: The rates of wrong ABO genotyping results could be effectively reduced by using altering primer P1'.


Assuntos
Sistema ABO de Grupos Sanguíneos/genética , Alelos , Primers do DNA/genética , Reação em Cadeia da Polimerase/métodos , Sequência de Bases , Genótipo , Humanos , Dados de Sequência Molecular , Sensibilidade e Especificidade
8.
Artigo em Inglês | MEDLINE | ID: mdl-27408716

RESUMO

BACKGROUND: Brucella is a zoonotic Gram-negative pathogen that causes abortion and infertility in ruminants and humans. TLR4 is the receptor for LPS which can recognize Brucella and initiate antigen-presenting cell activities that affect both innate and adaptive immunity. Consequently, transgenic sheep over-expressing TLR4 are an suitable model to investigate the effects of TLR4 on preventing Brucellosis. In this study, we generated transgenic sheep overexpressing TLR4 and aimed to evaluate the effects of different seasons (breeding and non-breeding season) on superovulation and the imported exogenous gene on growth. RESULTS: In total of 43 donor ewes and 166 recipient ewes in breeding season, 37 donor ewes and 144 recipient ewes in non-breeding season were selected for super-ovulation and injected embryo transfer to generate transgenic sheep. Our results indicated the no. of embryos recovered of donors and the rate of pronuclear embryos did not show any significant difference between breeding and non-breeding seasons (P > 0.05). The positive rate of exogenous TLR4 tested were 21.21 % and 22.58 % in breeding and non-breeding season by Southern blot. The expression level of TLR4 in the transgenic sheep was 1.5 times higher than in the non-transgenic group (P < 0.05). The lambs overexpressing TLR4 had similar growth performance with non-transgenic lambs, and the blood physiological parameters of transgenic and non-transgenic were both in the normal range and did not show any difference. CONCLUSIONS: Here we establish an efficient platform for the production of transgenic sheep by the microinjection of pronuclear embryos during the whole year. The over-expression of TLR4 had no adverse effect on the growth of the sheep.

9.
Theriogenology ; 80(1): 50-7, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23623352

RESUMO

An ovine fetal fibroblast cell line highly expressing TLR4 was established by inserting TLR4 into a reconstructive p3S-LoxP plasmid. Transgenic sheep overexpressing TLR4 were produced by transferring TLR4-transfected fetal fibroblasts into metaphase (M)II-stage enucleated oocytes (using SCNT). Because reconstructed embryos derived from MII-stage enucleated oocytes matured in vivo using a delayed-activated method had a higher pregnancy rate (18.52%) than that from MII-stage enucleated oocytes matured in vitro, the former procedure was used. Nine TLR4-transgenic live births were confirmed using polymerase chain reaction and Southern blot analysis. Increased expression of TLR4 at mRNA and protein levels in ear tissues of transgenic lambs were verified using reverse transcription polymerase chain reaction and immunohistochemistry, respectively. More toll-like receptor 4 protein was expressed by peripheral blood monocytes and/or macrophages collected from 3-month-old TLR4-transgenic than nontransgenic lambs at 0, 1, and 4 hours after lipopolysaccharide stimulation. Furthermore, interferon-γ and tumor necrosis factor α secreted by monocytes and/or macrophages of TLR4-transgenic lambs were significantly higher at 1 hour. Therefore, lipopolysaccharide-induced inflammatory responses from monocytes and/or macrophages occurred sooner in TLR4-transgenic lambs, consistent with an enhanced host immune response. In conclusion, transgenic sheep overexpressing TLR4 are a primary model to investigate the role of transgenic animals in disease resistance and have potential for breeding sheep with disease resistance.


Assuntos
Animais Geneticamente Modificados/fisiologia , Resistência à Doença/fisiologia , Expressão Gênica , Ovinos/fisiologia , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/fisiologia , Animais , Cruzamento , Clonagem de Organismos/métodos , Clonagem de Organismos/veterinária , Feminino , Feto/citologia , Fibroblastos/ultraestrutura , Vetores Genéticos , Lipopolissacarídeos/administração & dosagem , Macrófagos/imunologia , Monócitos/imunologia , Oócitos/ultraestrutura , Gravidez , RNA Mensageiro/análise , Receptor 4 Toll-Like/análise
10.
Theriogenology ; 78(2): 393-401, 2012 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-22592078

RESUMO

The objective was to investigate the effects of a novel DNA vaccine (pcISI) harboring two copies of inhibin α (1-32) fragments on immune response, hormone concentrations and reproductive performance in rats. Female Wistar rats (n=18 per group) were immunized (twice, 4 wk apart) with 10, 50, or 100 µg (T1, T2 and T3, respectively), of the pcISI plasmid. At 4 wk after the second immunization, plasma antibody titers were higher (P<0.05) in T3 than in either T1 or T2 (0.341±0.123, 0.236±0.068, and 0.251±0.077, respectively, mean±SD). Concurrrently, plasma concentrations of FSH and estradiol were highest (P<0.05) in T3, and were higher (P<0.05) in T1 and T2 than in control groups. For antibody-positive rats, there was a correlation (P<0.01) between antibody titer and FSH concentrations after two pcISI immunizations. The number of mature follicles in the T3 group (46.00±4.65) was higher (P<0.05) than in two control groups (29.25±3.72 and 27.92±3.48), and also higher (P<0.05) than in T1 and T2 (37.17±4.99 and 38.75±7.09). Antibody-positive rats had more mature ovarian follicles than negative rats (46.75±4.23 vs. 35.60±3.38, P<0.05). Moreover, litter size and number of placentas were increased (P<0.05) in the pcISI immunization groups, except for the T1 group, compared to the control groups. In conclusion, the pcISI DNA vaccine successfully induced a humoral immune response, improved reproductive hormone concentrations, stimulated follicular development, and increased number of placentas and litter size. Furthermore, 100 µg yielded the best immune response.


Assuntos
Inibinas/imunologia , Vacinas Anticoncepcionais/imunologia , Vacinas de DNA/imunologia , Animais , Anticorpos/sangue , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Esquemas de Imunização , Inibinas/química , Lipase , Folículo Ovariano , Plasmídeos , Ratos , Ratos Wistar
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA