Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
1.
Ecotoxicology ; 33(2): 151-163, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38329639

RESUMEN

Suspended particulate matter (SPM), an important component of the natural water environment, can act as a carrier of many pollutants that affect aquatic organisms. In the present study, the effect of SPM obtained from Jinjiang Estuary on the physiological, biochemical, and photosynthetic properties of typical freshwater algae (Chlorella pyrenoidosa) was investigated. The results showed that under different concentrations of SPM treatment, the superoxide dismutase (SOD), catalase (CAT) activities, and malondialdehyde (MDA) content of C. pyrenoidosa increased, but the soluble protein content decreased. SPM with different particle sizes had less effect on SOD of C. pyrenoidosa, but showed a promoting effect on CAT and MDA as well as soluble protein content. In terms of photosynthetic activity, high concentrations (70, 90 mg/L) and small particle sizes (0-75, 75-120 µm) of SPM had a greater effect on the chlorophyll a content of C. pyrenoidosa. In addition, different concentrations of SPM had no significant effect on the potential photosynthetic activity of PS II (Fv/F0) and the maximum quantum yield of PS II (Fv/Fm), but the inhibition of the initial slope (alpha), the maximum photosynthetic rate (ETRmax) and the semi-light saturation point (Ik) increased with the increase of SPM concentration. Fv/F0, ETRmax, and Ik of C. pyrenoidosa showed some degree of recovery after inhibition in the presence of SPM of different particle sizes.


Asunto(s)
Chlorella , Contaminantes Químicos del Agua , Clorofila A/metabolismo , Clorofila A/farmacología , Material Particulado/toxicidad , Material Particulado/metabolismo , Estuarios , Superóxido Dismutasa/metabolismo , Contaminantes Químicos del Agua/análisis
2.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(5): 450-455, 2024 May 15.
Artículo en Zh | MEDLINE | ID: mdl-38802903

RESUMEN

OBJECTIVES: To investigate the incidence rate, clinical characteristics, and prognosis of neonatal stroke in Shenzhen, China. METHODS: Led by Shenzhen Children's Hospital, the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022. The incidence, clinical characteristics, treatment, and prognosis of neonatal stroke in Shenzhen were analyzed. RESULTS: The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137, 1/6 060, and 1/7 704, respectively. Ischemic stroke accounted for 75% (27/36); boys accounted for 64% (23/36). Among the 36 neonates, 31 (86%) had disease onset within 3 days after birth, and 19 (53%) had convulsion as the initial presentation. Cerebral MRI showed that 22 neonates (61%) had left cerebral infarction and 13 (36%) had basal ganglia infarction. Magnetic resonance angiography was performed for 12 neonates, among whom 9 (75%) had involvement of the middle cerebral artery. Electroencephalography was performed for 29 neonates, with sharp waves in 21 neonates (72%) and seizures in 10 neonates (34%). Symptomatic/supportive treatment varied across different hospitals. Neonatal Behavioral Neurological Assessment was performed for 12 neonates (33%, 12/36), with a mean score of (32±4) points. The prognosis of 27 neonates was followed up to around 12 months of age, with 44% (12/27) of the neonates having a good prognosis. CONCLUSIONS: Ischemic stroke is the main type of neonatal stroke, often with convulsions as the initial presentation, involvement of the middle cerebral artery, sharp waves on electroencephalography, and a relatively low neurodevelopment score. Symptomatic/supportive treatment is the main treatment method, and some neonates tend to have a poor prognosis.


Asunto(s)
Accidente Cerebrovascular , Humanos , Masculino , Recién Nacido , Femenino , China/epidemiología , Accidente Cerebrovascular/epidemiología , Pronóstico , Electroencefalografía , Incidencia , Imagen por Resonancia Magnética
3.
Comp Cytogenet ; 18: 73-95, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38798789

RESUMEN

To characterize the chromosomes of the four species of Polygonatum Miller, 1754, used in traditional Chinese medicine, P.cyrtonema Hua, 1892, P.kingianum Collett et Hemsley, 1890, P.odoratum (Miller, 1768) Druce, 1906, and P.sibiricum Redouté, 1811, and have an insight into the karyotype variation of the genus Polygonatum, fluorescence in situ hybridization (FISH) with 5S and 45S rDNA oligonucleotide probes was applied to analyze the karyotypes of 9 populations of the four species. Detailed molecular cytogenetic karyotypes of the 9 populations were established for the first time using the dataset of chromosome measurements and FISH signals of 5S and 45S rDNA. Four karyotype asymmetry indices, CVCI, CVCL, MCA and Stebbins' category, were measured to elucidate the asymmetry of the karyotypes and karyological relationships among species. Comparison of their karyotypes revealed distinct variations in the karyotypic parameters and rDNA patterns among and within species. The basic chromosome numbers detected were x = 9, 11 and 13 for P.cyrtonema, x = 15 for P.kingianum, x = 10 and 11 for P.odoratum, and x = 12 for P.sibiricum. The original basic chromosome numbers of the four species were inferred on the basis of the data of this study and previous reports. All the 9 karyotypes were of moderate asymmetry and composed of metacentric, submetacentric and subtelocentric chromosomes or consisted of two of these types of chromosomes. Seven populations have one locus of 5S rDNA and two loci of 45S rDNA, and two populations added one 5S or 45S locus. The karyological relationships among the four species revealed by comparison of rDNA patterns and PCoA based on x, 2n, TCL, CVCI, MCA and CVCL were basically accordant with the phylogenetic relationships revealed by molecular phylogenetic studies. The mechanisms of both intra- and inter-specific dysploidy in Polygonatum were discussed based on the data of this study and literature.

4.
PLoS One ; 18(2): e0278342, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36827361

RESUMEN

OBJECTIVE: To compare the therapeutic effects of emergency cervical cerclage and expectant treatment in preterm birth due to cervical insufficiency in singleton pregnancy. METHODS: A combination of subject words and free words was used to search major domestic and foreign databases. According to inclusion and exclusion criteria, 23 studies were included that met the criteria and quality evaluation and data extraction was carried out. The data were analyzed using STATA 15 and the reporting was done in reference to the list of Preferred Reporting Items for Systematic and Meta-Analyses. RESULTS: Emergency cervical cerclage was superior to expectant treatment for the primary outcome of pregnancy prolongation (WMD = 5.752, 95% CI 5.194-6.311, 22 studies, N = 1435, I2 = 97.1%, P = 0.000). Cervical cerclage was also superior to expectant treatment for the secondary outcomes of neonatal birth weight (WMD = 1051.542, 95% CI 594.107-1508.977, 9 studies, N = 609, I2 = 96.4%, P = 0.000), neonatal Apgar 1' (WMD = 2.8720, 95% CI: 2.105-3.639, 11 studies, N = 716, I2 = 99.0%, P = 0.000), number of live births (OR = 6.018, 95% CI 2.882-12.568, 10 studies, N = 724, I2 = 55.3%, P = 0.000), deliveries after 32 weeks (OR = 8.030, 95% CI 1.38-46.892, 8 studies, N = 381, I2 = 85.9%, P = 0.021). deliveries after 34 weeks (OR = 15.91, 95% CI 5.92-42.77, 9 studies, N = 560, I2 = 59.6%, P = 0.000), number of vaginal deliveries (OR = 3.24, 95% CI 1.32-7.90, 8 studies, N = 502, I2 = 69.4%, P = 0.018), and number of neonatal survivals (OR = 9.300, 95% CI 3.472-24.910, 10 studies, N = 654, I2 = 80.5%, P = 0.000). No difference between emergency cervical cerclage and expectant treatment was found in patients with chorioamnionitis (OR = 1.85, 95% CI 0.602-4.583, 4 studies, N = 296, I2 = 16.3%, P = 0.273). CONCLUSION: Before the 28th week of pregnancy, emergency cervical cerclage can significantly prolong the gestational week and improve the neonatal survival rate, compared to expectant treatment, in women with singleton pregnancies who have a dilated uterine orifice caused by cervical insufficiency.


Asunto(s)
Cerclaje Cervical , Nacimiento Prematuro , Incompetencia del Cuello del Útero , Embarazo , Recién Nacido , Humanos , Femenino , Cerclaje Cervical/efectos adversos , Nacimiento Prematuro/etiología , Resultado del Embarazo , Estudios Retrospectivos
5.
Am J Cancer Res ; 13(11): 5218-5235, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38058799

RESUMEN

This research is dedicated to investigating the mechanism of programmed cell death ligand 1 (PD-L1) and tumor protein 53 target gene 1 (TP53TG1) in immune regulation of colon cancer (CC). Expressions of TP53TG1, PD-L1 and signal transducers and activators of transcription (STATs) in CC and their correlation were detected through bioinformatics analysis. Effects of PD-L1 and TP53TG1 on the CC were assessed by in vivo and in vitro experiments. Herein, PD-L1 level was negatively correlated with TP53TG1 expression, but was positively correlated with the levels of STATs. Both overexpressed TP53TG1 and PD-L1 antibody reversed the effects of CT26 cells on inhibiting cell proliferation, cytokine secretion and PD-L1 level, and enhancing the cytotoxicity of NK cells and CD8+ T cells. TP53TG1 reduced PD-L1 level by inactivating STATs pathway. Downregulation of PD-L1 increased cytokine secretion and T lymphocyte killing ability, promoted tumor cell apoptosis, and inhibited the tumor growth. Altogether, TP53TG1/STAT axis regulates the immunomodulatory mechanism of CC by reducing PD-L1 expression.

6.
Digit Health ; 9: 20552076231219444, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38107984

RESUMEN

Objective: The aim is to investigate the determinants and mechanisms that influence user's highly sensitive privacy disclosure intention (HSPDI) in home intelligent health service system (HIHSS). Methods: This study improves the privacy calculus theory by considering the influence of service providers' trust enhancement mechanism besides benefit and risk factors and investigates their impact on users' HSPDIs. This study takes perceived valence and perceived security as the trade-off result among perceived benefits, perceived risks, financial trust enhancement mechanism, and the technical trust enhancement mechanism and suggests that perceived valence and perceived security further affect users' HSPDI in HIHSS. Moreover, the common and differential effects of the perceived justice of privacy violation compensation (PJOPVC) and the perceived effectiveness of privacy protection technologies (PEOPPTs) are studied. The structural equation model is used to analyze 204 valid samples to test the proposed model. Results: The results show that perceived benefits and perceived risks are important predictors of perceived valence and perceived security, and further affect users' HSPDI. We find PJOPVC has a greater impact on perceived valence while PEOPPT has a greater impact on perceived security. Conclusions: We recommend that the HSPDI of users with low perceived valence can be improved by providing privacy violation compensation while the HSPDI of users with low perceived security can be enhanced by popularizing relevant knowledge of privacy protection technologies.

7.
Huan Jing Ke Xue ; 34(1): 156-62, 2013 Jan.
Artículo en Zh | MEDLINE | ID: mdl-23487932

RESUMEN

The effects of ethyl cinnamate on the growth and physiological characteristics of Chlorella pyrenoidosa were studied. The allelopathic mechanisms were explored, from views of chlorophyll a content, antioxidant enzyme activities, reactive oxygen species (ROS) level, malondialdehyde (MDA) content and photosynthetic activity. The results revealed that ethyl cinnamate had acute inhibitory effects on the growth of Chlorella pyrenoidosa, and the inhibited degree tended to increase with increased concentrations. The effective concentration causing a 50% inhibition at 96 h was 5.45 mg c L(-1). Ethyl cinnamate induced the decrease of chlorophyll a, the over-accumulation of ROS and the increase of MDA. Therefore, it suggested that ethyl cinnamate could lead to the damage of cell membrane system and metabolic disorder through inducing lipid peroxidation via initiating ROS overproduction. And for scavenging ROS, the algae cells were protected from oxidative damages through increasing the activity of antioxidant enzymes. The results demonstrated ethyl cinnamate had acute inhibition to the maximum quantum yield and the potential activity of photosystem II of Chlorella pyrenoidosa, however, the photosynthetic activity could recover to some extent through self-regulation after some time.


Asunto(s)
Chlorella/efectos de los fármacos , Chlorella/crecimiento & desarrollo , Cinamatos/farmacología , Feromonas/farmacología , Chlorella/fisiología , Clorofila/metabolismo , Clorofila A , Complejo de Proteína del Fotosistema II/efectos de los fármacos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA