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1.
Glob Chang Biol ; 29(13): 3575-3590, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37021594

RESUMEN

Enhancing soil organic carbon (SOC) sequestration and food supply are vital for human survival when facing climate change. Site-specific best management practices (BMPs) are being promoted for adoption globally as solutions. However, how SOC and crop yield are related to each other in responding to BMPs remains unknown. Here, path analysis based on meta-analysis and machine learning was conducted to identify the effects and potential mechanisms of how the relationship between SOC and crop yield responds to site-specific BMPs in China. The results showed that BMPs could significantly enhance SOC and maintain or increase crop yield. The maximum benefits in SOC (30.6%) and crop yield (79.8%) occurred in mineral fertilizer combined with organic inputs (MOF). Specifically, the optimal SOC and crop yield would be achieved when the areas were arid, soil pH was ≥7.3, initial SOC content was ≤10 g kg-1 , duration was >10 years, and the nitrogen (N) input level was 100-200 kg ha-1 . Further analysis revealed that the original SOC level and crop yield change showed an inverted V-shaped structure. The association between the changes in SOC and crop yield might be linked to the positive role of the nutrient-mediated effect. The results generally suggested that improving the SOC can strongly support better crop performance. Limitations in increasing crop yield still exist due to low original SOC level, and in regions where the excessive N inputs, inappropriate tillage or organic input is inadequate and could be diminished by optimizing BMPs in harmony with site-specific conditions.


Asunto(s)
Agricultura , Suelo , Humanos , Suelo/química , Agricultura/métodos , Carbono/análisis , Secuestro de Carbono , China , Productos Agrícolas
2.
J Environ Manage ; 329: 117065, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36566726

RESUMEN

Recommended management practices (RMPs, e.g., manuring, no-tillage, crop residue return) can increase soil organic carbon (SOC), reduce greenhouse gas emissions, and maintain soil health in croplands. However, there is no consensus on how RMPs affect the SOC storage potential of cropland soils for climate change mitigation. Here, based on 2301 comparisons from 158 peer-reviewed papers, a meta-analysis was conducted to explore management-induced SOC stock changes and their variations under different conditions. The results show that SOC stocks in the 0-20 cm layer were increased by 31.8% when chemical fertilization combined with manure application was compared with no fertilizer; 9.98% when no-tillage was compared with plow tillage; and 10.84% when straw return was compared with removal. The RMPs favorably increased SOC stock in arid areas, and in alkaline and fine-textured soils. Initial SOC, carbon-nitrogen ratio, and experimental duration could also affect SOC storage. Compared with the initial SOC stock, RMPs increased the SOC sequestration potential by 2.6-4.5% in the 0-20 cm soil depth, indicating that these practices can help China achieve targets to increase SOC by 4.0‰. Hence, it is essential to implement RMPs for climate change mitigation and soil fertility improvement.


Asunto(s)
Agricultura , Suelo , Suelo/química , Agricultura/métodos , Carbono/análisis , Productos Agrícolas , China , Secuestro de Carbono , Estiércol/análisis
3.
Int J Cancer ; 138(4): 918-26, 2016 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-26314689

RESUMEN

A DNA aptamer was identified against the shared tumor-specific MAGE-A3111-125 peptide antigen. The dissociation constant between the aptamer and the peptide was measured at 57 nM. Binding of the aptamer to seven types of cancer cells, melanoma, breast, colorectal, liver, lung, pancreas and oral cancer, was confirmed with flow cytometry and fluorescence imaging. Cy3-conjugated aptamers signals were specifically localized to the surface of those cancer cells. The results indicate that the DNA aptamer against the shared tumor-specific MAGE-A3 peptide can be used in cancer cell targeting and has the potential for developing into new modalities for the diagnosis of multiple cancers.


Asunto(s)
Antígenos de Neoplasias/metabolismo , Aptámeros de Nucleótidos/síntesis química , Aptámeros de Nucleótidos/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Calorimetría , Línea Celular Tumoral , Citometría de Flujo , Humanos , Immunoblotting , Microscopía Confocal , Unión Proteica , Técnica SELEX de Producción de Aptámeros , Transfección
4.
Biochem Biophys Res Commun ; 471(1): 95-102, 2016 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-26845356

RESUMEN

Hepatitis C virus (HCV) nonstructural protein 5B (NS5B) functions as an RNA-dependent RNA polymerase in the HCV replication complex derived from the endoplasmic reticulum in hepatic cells. In this study, NS5B was used as bait in a yeast two-hybrid assay to screen a human liver cDNA library. We confirmed that CYP4F12, a member of the cytochrome P450 superfamily, interacted with NS5B. Furthermore, overexpression of CYP4F12 facilitated HCV replication. In contrast, knockdown of CYP4F12 by specific shRNA decreased HCV replication and viral protein expression. Moreover, our results demonstrated that HCV infection increased the binding of the transcription factor SREBP1 to the CYP4F12 promoter and activated the promoter activity, which indicated that HCV infection increased the expression of CYP4F12 through the SREBP1 pathway. Our results showed that HCV infection induced expression of CYP4F12 protein, which bound to the HCV replication complex to facilitate viral replication.


Asunto(s)
Hidrocarburo de Aril Hidroxilasas/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/virología , Hepacivirus/fisiología , Proteínas no Estructurales Virales/metabolismo , Replicación Viral/fisiología , Línea Celular Tumoral , Hepatitis C/metabolismo , Hepatitis C/virología , Humanos
5.
Appl Microbiol Biotechnol ; 100(1): 1-8, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26476642

RESUMEN

Polysialic acid (PSA) is a unique polysaccharide that plays critical roles in many bioprocesses, which makes it useful in a wide range of biomedical applications. The increased demand for PSA has led to considerable efforts to improve its production using bacteria, such as Escherichia coli. Bioprocess optimization and metabolic engineering have allowed the efficient production of PSA. This review aims to summarize the metabolism of PSA with an emphasis on the importance of the key pathway components. In addition, this review provides an update on state of the art PSA production using E. coli with a special emphasis on strategies of strain engineering and process development for the enhanced production of PSA.


Asunto(s)
Biotecnología , Escherichia coli/metabolismo , Ingeniería Metabólica , Ácidos Siálicos/biosíntesis , Ácidos Siálicos/metabolismo , Redes y Vías Metabólicas/genética
6.
Appl Microbiol Biotechnol ; 99(6): 2603-11, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25620366

RESUMEN

A number of reports have described the production of polysialic acid (PSA), focusing on the fermentation and purification of PSA. However, little work has been done to strengthen the synthetic pathway of PSA to improve PSA production. In this study, an efficient process for enhanced production of PSA using a recombinant Escherichia coli strain was developed. To improve the PSA production efficiency, the key enzymes of PSA synthetic pathway were overexpressed separately or in combination, including N-acetylneuraminate (Neu5Ac) 7-O(or 9-O)-acetyltransferase (NeuD), CMP-Neu5Ac synthetase (NeuA), and alpha-Neu5Ac alpha-2,8-sialyltransferase (NeuS). The PSA production was significantly improved by coexpression of NeuD and NeuA. In terms of the efficiency, NeuD was considered as the most important factor. Secondly, the competing pathway of intermediate Neu5Ac was blocked by nanA deletion. The efficient PSA-producing strain E. coli SA9ΔnanA/pDB1S-DA was constructed, and 16.15 ± 1.45 g/L PSA was obtained in the fed-batch culture. The production of PSA by engineered strain was increased by 85 % compared to the original strain. These results provide evidence for improvement of PSA production by regulation of the PSA biosynthetic pathway. The high productivity of our process should make it a promising cost-effective resource for PSA.


Asunto(s)
Escherichia coli/enzimología , Escherichia coli/genética , Ingeniería Metabólica , Ácidos Siálicos/biosíntesis , Acetiltransferasas/metabolismo , Vías Biosintéticas , Proteínas de Escherichia coli/metabolismo , Fermentación , Peso Molecular , Sialiltransferasas/metabolismo
7.
Artif Intell Med ; 151: 102828, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38564879

RESUMEN

Reliable large-scale cell detection and segmentation is the fundamental first step to understanding biological processes in the brain. The ability to phenotype cells at scale can accelerate preclinical drug evaluation and system-level brain histology studies. The impressive advances in deep learning offer a practical solution to cell image detection and segmentation. Unfortunately, categorizing cells and delineating their boundaries for training deep networks is an expensive process that requires skilled biologists. This paper presents a novel self-supervised Dual-Loss Adaptive Masked Autoencoder (DAMA) for learning rich features from multiplexed immunofluorescence brain images. DAMA's objective function minimizes the conditional entropy in pixel-level reconstruction and feature-level regression. Unlike existing self-supervised learning methods based on a random image masking strategy, DAMA employs a novel adaptive mask sampling strategy to maximize mutual information and effectively learn brain cell data. To the best of our knowledge, this is the first effort to develop a self-supervised learning method for multiplexed immunofluorescence brain images. Our extensive experiments demonstrate that DAMA features enable superior cell detection, segmentation, and classification performance without requiring many annotations. In addition, to examine the generalizability of DAMA, we also experimented on TissueNet, a multiplexed imaging dataset comprised of two-channel fluorescence images from six distinct tissue types, captured using six different imaging platforms. Our code is publicly available at https://github.com/hula-ai/DAMA.


Asunto(s)
Encéfalo , Encéfalo/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Aprendizaje Automático Supervisado , Humanos , Aprendizaje Profundo , Animales , Algoritmos , Neuroimagen/métodos
8.
Mar Environ Res ; 193: 106296, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38113589

RESUMEN

A recent study based on gonad histology revealed that the existence of the spawning grounds for Gray's grenadier anchovy (Coilia grayii) and Osbeck's grenadier anchovy (C. mystus) in the Min River Estuary, the largest in Fujian Province, southern China. Further confirming their natal sources and migratory patterns is essential to understand their life histories. We used otolith microchemistry to assess the origins and habitat uses of 23 C. grayii and 22 C. mystus, collected the Min River Estuary and the adjacent waters. The results showed that C. grayii spawned in both freshwater (n| = 14) and brackish water (n = 9), and C. mystus spawned mainly in brackish water (n| = 20) with minor in freshwater (n| = 1) and marine water (n| = 1). The migratory patterns of C. grayii (four types) and C. mystus (five types) were diverse, mainly exhibiting anadromous and semi-anadromous behaviors. The first migratory behavior of C. grayii and C. mystus occurred within the age of the first year. The findings have significant implications for fishery stock management of the Min River Estuary and its adjacent waters.


Asunto(s)
Membrana Otolítica , Ríos , Animales , Estuarios , Microquímica , Peces , China
9.
Appl Microbiol Biotechnol ; 97(11): 4775-84, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23420269

RESUMEN

N-Acetyl-D-neuraminic acid (Neu5Ac) has attracted considerable interest due to its promising potential applications in medicine. Significant efforts have been made in whole-cell biocatalyst for Neu5Ac production, but the processes often result in suboptimal performance due to poor expression of enzymes, imbalances of pathway components, disturbance of competing pathways, and barriers of mass transport. In this study, we engineered Escherichia coli strains capable of producing Neu5Ac by assembling a two-step heterologous pathway consisting of N-acetyl-D-glucosamine 2-epimerase (AGE) and Neu5Ac aldolase (NanA). Multiple approaches were used to improve the efficiency of the engineered pathway and process for enhanced Neu5Ac production. Firstly, we identified that NanA was the rate-controlling enzyme in this pathway. With increased expression of NanA, a ninefold increase in Neu5Ac production (65 mM) was observed. Secondly, knocking out nanTEK genes blocked Neu5Ac uptake and the competing pathway, which kept the reactions to the synthetic direction as the final product went outside of the cells and enhanced the Neu5Ac production by threefold, resulting in 173.8 mM of Neu5Ac. Thirdly, we improved the performance of the system by promoting substrate transport and optimizing concentrations of substrates. An overall whole-cell biocatalytic process was developed and a maximum titer of 240 mM Neu5Ac (74.2 g/L) was achieved, with productivity of 6.2 g Neu5Ac/L/h and conversion yield of 40 % from GlcNAc. The engineered strain could be reused for at least five cycles with a productivity of >6 g/L/h. It is a cost-effective process for Neu5Ac production with potential applications in large-scale industrial production.


Asunto(s)
Biotecnología/métodos , Enzimas/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Ingeniería Metabólica/métodos , Ácido N-Acetilneuramínico/metabolismo , Enzimas/genética , Fermentación , Eliminación de Gen , Expresión Génica , Redes y Vías Metabólicas/genética
10.
Biomed Res Int ; 2023: 7745815, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36726842

RESUMEN

Physical activity (PA) in which physical exercise (PE) is an important component is probably the most important intervention for preventing noncommunicable diseases (NCDs). However, few studies on PA and PE of rural residents in China were reported. This study conducted the first population-based cross-sectional survey in three provinces of China in 2021 that examined both PA and PE as well as the associated factors of rural residents. The International Physical Activity Questionnaire Short Form (IPAQ-S) was used, and a total of 3780 rural residents were surveyed. The result showed that 22.2% of the rural residents were physical inactivity and rural residents reporting practice of PE was 54.4%. Binary logistic regression analyses showed that being female, people aged between 15 to 34 years or 60 years old and above, employees of governmental departments/retirees, school students, the unemployed, and people with NCDs were risk factors of PA while ethnic minority groups, smoking, and alcohol consumption were risk factors of PE. Health promotion programme aiming at increasing people's PA in rural China is urgently needed, and it should focus on the population groups of the female, people aged 60 years and above, school students, the unemployed, and people with NCDs.


Asunto(s)
Etnicidad , Grupos Minoritarios , Humanos , Femenino , Adolescente , Adulto Joven , Adulto , Masculino , Estudios Transversales , Ejercicio Físico , Población Rural , China/epidemiología
11.
Sci Total Environ ; 842: 156822, 2022 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-35738372

RESUMEN

Conservation agriculture (CA) can be an important strategy for improving soil organic carbon (SOC) and total nitrogen (TN). Numerous studies have examined SOC and TN dynamics in different cropping systems. However, there is some uncertainty regarding the relative impacts of some CA practices, and it is not always clear how other agricultural management, particularly nitrogen addition, interacts with these practices to influence SOC and TN sequestration. Thus, we conducted a global meta-analysis of 752 comparisons from 97 papers to analyze the impacts of nitrogen fertilizers and CA practices (namely crop diversification, minimal soil disturbance (no-tillage) and permanent soil cover), on SOC and TN content worldwide. Overall, our study showed the most significant increase of SOC [21.39 % (CI = 15.16 to 28.64)] and TN [54.34 % (CI = 26.19 to 96.69)] stock with CA practices compared to conventional practices in the 0-15 cm soil depth. It also showed a significant increase in SOC and TN stock with all the individual components of CA compared to conventional practices in the 0-15 cm soil depth. However, the impact of CA on SOC and TN is reduced in 0-60 cm depths compared to surface soil depths due to the limited input of crop residue deeper in the soil profile. Manure and manure mixed with mineral-N led to greater SOC sequestration [20.67 % (CI = 15.23 to 27.10) and 41.67 % (CI = 31.03 to 52.79), respectively] than mineral-N alone [9.08 % (CI = 6.44 to 11.83)]. Cropping systems that included legume residue decreased the C/N ratio. This highlights that adequate mineral-N fertilizer addition may also be required in conjunction with residue retention practices to improve SOC and TN content. Overall, these results show that CA systems that include legume residue and manure mixed with mineral-N have great potential to increase SOC and TN, particularly at 0-15 cm and 0-30 cm soil depth.


Asunto(s)
Nitrógeno , Suelo , Agricultura/métodos , Carbono/química , Secuestro de Carbono , Fertilizantes , Estiércol , Minerales , Nitrógeno/análisis , Suelo/química
12.
BMC Genomics ; 12: 439, 2011 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-21880155

RESUMEN

BACKGROUND: To elucidate the molecular complications in many complex diseases, we argue for the priority to construct a model representing the normal physiological state of a cell/tissue. RESULTS: By analyzing three independent microarray datasets on normal human tissues, we established a quantitative molecular model GET, which consists of 24 tissue-specific Gene Expression Templates constructed from a set of 56 genes, for predicting 24 distinct tissue types under disease-free condition. 99.2% correctness was reached when a large-scale validation was performed on 61 new datasets to test the tissue-prediction power of GET. Network analysis based on molecular interactions suggests a potential role of these 56 genes in tissue differentiation and carcinogenesis.Applying GET to transcriptomic datasets produced from tissue development studies the results correlated well with developmental stages. Cancerous tissues and cell lines yielded significantly lower correlation with GET than the normal tissues. GET distinguished melanoma from normal skin tissue or benign skin tumor with 96% sensitivity and 89% specificity. CONCLUSIONS: These results strongly suggest that a normal tissue or cell may uphold its normal functioning and morphology by maintaining specific chemical stoichiometry among genes. The state of stoichiometry can be depicted by a compact set of representative genes such as the 56 genes obtained here. A significant deviation from normal stoichiometry may result in malfunction or abnormal growth of the cells.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Genoma Humano , Neoplasias/genética , Especificidad de Órganos , Línea Celular , Análisis por Conglomerados , Bases de Datos Genéticas , Redes Reguladoras de Genes , Humanos , Anotación de Secuencia Molecular , Análisis de Secuencia por Matrices de Oligonucleótidos , Sensibilidad y Especificidad , Piel/metabolismo
13.
Cancer Biol Ther ; 22(1): 12-18, 2021 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-33249980

RESUMEN

We developed a DNA aptamer, Ap52, against the shared tumor-specific MAGE-A3111-125 peptide antigen that was used to target multiple types of cancer cells. Here we report the in vivo study of mice implanted with pancreatic tumor cells AsPC-1, which demonstrates accumulation of phosphorothioate-modified Ap52 (ThioAp52) at the xenograft tumor following either intravenous or in situ injection. When complexed with antitumor drug doxorubicin (Dox), ThioAp52 achieves targeted delivery to four types of cancer cells, including breast, oral, pancreatic, and skin. Image analysis shows that ThioAp52-Dox complex selectively enters cancer cells, while free Dox is taken up by all cell lines. The cytotoxicity of ThioAp52-Dox for cancer cells is enhanced as compared to that for the corresponding normal/noncancerous cells. These results indicate that this aptamer against shared tumor-specific antigen can be a potential delivery vehicle for therapeutics to treat multiple cancers.


Asunto(s)
Antígenos de Neoplasias/metabolismo , Aptámeros de Nucleótidos/metabolismo , Sistemas de Liberación de Medicamentos/métodos , Proteínas de Neoplasias/metabolismo , Péptidos/metabolismo , Animales , Humanos , Masculino , Ratones
14.
Zool Stud ; 60: e33, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34963786

RESUMEN

A total of 40 juveniles belonging to a temperate deepwater gnomefish species, Scombrops boops, were sampled from littoral habitats (2-5 m depth) of eastern Hong Kong waters in April and May 2017 and March 2019. The presence of gnomefish juveniles in subtropical southern China is reported for the first time at a record low latitude of 22°11'-22°21'N. The specimens were identified based on the COI gene sequence. The genetic composition between Japan and Hong Kong gnomefish populations were compared by sequencing the mitochondrial Cytb gene, which showed no genetic differentiation. The juveniles ranged from 3.5-10.1 cm (n = 40) in total length, with 35 individuals caught from Sargassum beds and five from rocky reefs. Our findings highlighted that the littoral habitats in Hong Kong waters, in particular the seasonal Sargassum beds, are important for small juveniles of S. boops.

15.
Am J Cancer Res ; 11(6): 2654-2669, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34249420

RESUMEN

Colorectal cancer patients with synchronous liver metastases (CRSLM) can be treated by simultaneous surgery, that is the primary tumor and liver metastasis are removed at the same time. However, criteria for simultaneous surgery are underwent continuously modified and expanded. An appropriate selection of adequate candidates for simultaneous surgery is vital to get best benefits. A retrospective study including CRSLM patients underwent simultaneous surgical treatment was conducted. CRSLM patients from SEER database were screened as development set, while CRSLM patients in Harbin (China) were enrolled as validation set. Overall survival (OS) and cancer-specific survival (CSS) were applied as end-point. Variables were screen by LASSO-Cox regression, then Cox regression was applied to construct 1-, 3- and 5-year OS, and CSS nomograms. Nomograms were compared to TMN stage for survival prediction and evaluated by concordance indexes (C-indexes), Time-dependent receiver operating characteristic (ROC) curves, Decision Curve Analysis (DCA). 1347 and 112 CRSLM patients were included in the development set and validation set respectively. Nine factors were found associated with OS and CSS, i.e., Age, Primary Site, Differentiation grade, Histology type, T stage, N stage, Tumor size, Chemotherapy, CEA. Compared to the TNM stage, OS nomogram in development set and validation set got C-indexes values of 0.701 vs 0.641, 0.670 vs 0.557 respectively. Meanwhile, compared to the TNM stage, CSS nomogram in development set and validation set got C-indexes values of 0.704 vs 0.649, 0.677 vs 0.569 respectively. AUC values of the OS and CSS nomograms were higher than the TNM stage, DCA showed the OS and CSS nomograms got more clinical net benefit than the TNM stage, in both the development set and validation set. Our nomograms for predicting survival might be helpful to identify the right CRSLM patients who can get most benefit from simultaneous surgery.

16.
Respiration ; 80(1): 24-31, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-19864882

RESUMEN

BACKGROUND: Bronchial artery (BA) embolization (BAE) is recommended as a minimally invasive therapy for hemoptysis, though some patients recover after only conservative treatment. OBJECTIVES: The purpose of our study was to assess the characteristics of BAs using multidetector row computed tomography (MDCT) and identify BAs requiring BAE without BA angiography (BAG). METHODS: We retrospectively studied 41 patients and classified the visualized BAs into groups based on their BAE and bleeding statuses. Patients presenting with massive hemoptysis requiring emergency BAE were excluded. Patients presenting with persistent hemoptysis that was resistant to conservative treatment received BAE. Radiologists measured BA diameters at the ostium, bronchial bifurcation and pulmonary hilum, and also evaluated the degree of vascularization. RESULTS: MDCT enabled visualization of 102 ostia and 96 traceable BAs. Among the participating patients, 13 had at least one ectopic origin. We obtained a good correlation between BAG and MDCT diameters (r = 0.709, p < 0.001). The diameters of BAs responsible for bleeding and receiving BAE were apparently larger in each measured segment than those that were not (p < 0.05). Moreover, the diameters of arteries receiving BAE remained largely unchanged from the origin to the hilum and through the mediastinum. BAs with low MDCT scores were significantly less likely to required BAE than those with high scores (p = 0.004), and in multiple logistic regression analysis, ostium diameter and bleeding status were independent predictive factors for BAE. CONCLUSIONS: Evaluation of BAs on MDCT could be useful for identifying the anatomical characteristics of bleeding-related BAs and determining whether BAE is indicated or whether conservative treatment is sufficient.


Asunto(s)
Arterias Bronquiales , Embolización Terapéutica , Hemoptisis/diagnóstico por imagen , Hemoptisis/terapia , Tomografía Computarizada por Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Hemoptisis/etiología , Humanos , Masculino , Persona de Mediana Edad , Selección de Paciente , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Resultado del Tratamiento
17.
J Plant Res ; 123(5): 645-53, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20091204

RESUMEN

Diurnal phototropism has not been reported in ferns. In this study we found that the four leaflets of the amphibious fern Marsilea quadrifolia are capable of adjusting their leaflet angle and leaflet azimuth in response to changes in the position of the sun's direct beam, exhibiting more diaphototropic movements (orienting the plane of the lamina perpendicular to incident light) in the morning and late afternoon, and more paraphototropic movements (orienting the plane of the lamina parallel to incident light) at noon. In addition, by cutting off the leaflet lamina and covering portions of leaflets with black tape, the junction between the leaflet and petiole was found to be responsible for light reception. Among the light spectrum investigated, blue light was the most effective at inducing diaphototropism. The role of diurnal phototropism in enhancing carbon return and ameliorating photoinhibition was also evaluated. It was concluded that diurnal phototropic leaf movement represents one of the plastic responses enabling this amphibious fern to grow under terrestrial conditions.


Asunto(s)
Marsileaceae/fisiología , Fotosíntesis/fisiología , Fototropismo/fisiología , Luz , Hojas de la Planta/fisiología
18.
Mitochondrial DNA B Resour ; 5(1): 920-921, 2020 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-33366810

RESUMEN

In this study, the complete mitogenome of a new species, Johnius taiwanensis (Chao et al. 2019) was obtained. Its mitogenome is 18,451 bp in length, consisting of 37 genes with the typical gene order and direction of transcription in vertebrates. Gene rearrangement was found in J. taiwanensis. The overall nucleotide composition is: 24.2% A; 18.0% C; 21.1% G, and 36.7% T. Sizes of the 22 tRNA genes range from 66 to 75 bp. Two start codons (ATG and GTG) and three stop codons (TAG, AGA and TAA/TA/T) were detected in 13 protein-coding genes. In the Bayesian tree based on the complete mitogenomes of 26 species (including J. taiwanensis) from the family Sciaenidae, all nodes were strongly supported. The result shows that J. taiwanensis was placed as sister to the Trewavas croaker J. trewavasae of the same genus. The mechanism of gene rearrangement in the genus Johnius merits further investigation.

19.
Front Pharmacol ; 11: 582929, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33551797

RESUMEN

Background: CYP2C19 loss-of-function (LOF) alleles reduce the effectiveness of clopidogrel in patients undergoing percutaneous coronary intervention for acute coronary syndrome. However, the clinical impact of implementing CYP2C19 gene-guided pharmacotherapy is unclear, especially among the Chinese population. The purpose of this study was to evaluate P2Y12 receptor inhibitor selection and clinical outcomes upon implementation of CYP2C19 genotype-guided pharmacotherapy in current clinical practice. Methods: This was a single-center observational cohort study. Adult percutaneous coronary intervention patients who received CYP2C19 genetic testing (*2, *3, *17 alleles) were included. Ticagrelor was recommended for patients with a LOF allele. Factors related to P2Y12 inhibitor selection were determined by logistic regression. The primary endpoint was major cardiac or cerebrovascular adverse events (MACCE) within 12 months. MACCE and clinically significant bleeding events (BARC ≥2) in the LOF-clopidogrel group, non-LOF-clopidogrel group, and non-LOF-ticagrelor group were compared with those in the LOF-ticagrelor group. The inverse probability of treatment weighting (IPTW) was adjusted in a Cox regression analysis to eliminate confounding factors. Results: Among 1,361 patients, 826 (60.7%) had a LOF allele. Patients with a LOF allele were more likely to be prescribed ticagrelor (multivariate-adjusted OR 1.349; 95% CI 1.040 to 1.751; p = 0.024). The MACCE rate was higher in the LOF-clopidogrel group than in the LOF-ticagrelor group (7.8 vs. 4.0%; log-rank p = 0.029; IPTW-adjusted HR 2.138; 95% CI 1.300-3.515). Compared with the LOF-ticagrelor group, the non-LOF-clopidogrel group showed no significant difference in MACCE rate (5.8 vs. 4.0%; log-rank p = 0.272; IPTW-adjusted HR 1.531; 95% CI 0.864-2.714). Among the patients treated with ticagrelor, there was no significant difference in the MACCE rate between the LOF group and non-LOF group (4.3 vs. 4.0%; log-rank p = 0.846; IPTW-adjusted HR 1.184; 95% CI 0.582-2.410). There was no significant difference in the incidence of clinically significant bleeding events among the four groups. Conclusion: This study confirms that efficiently returned CYP2C19 genotype results did partially guide cardiologists to prescribe ticagrelor for patients with a LOF allele, and that clopidogrel had a higher risk of MACCE than ticagrelor in these patients, which provides support for the implementation of CYP2C19 gene-guided antiplatelet therapy in clinical practice.

20.
J Asthma ; 46(2): 142-6, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19253119

RESUMEN

The purpose of this study was to assess the effect on bone mineral density (BMD) of systemic corticosteroid (SCS) intermittently administered for rescue from asthmatic exacerbation. Through digital image processing and calculation of four other indices, BMD was compared in groups of asthmatic patients receiving inhaled corticosteroid (ICS) alone or ICS plus intermittent SCS. We defined SCS as intermittent administration of the equivalent of 1 mg/day prednisolone in the management of asthma exacerbations during the previous 1 year. Serum NTX, a bone resorption marker, was significantly higher (p = 0.02) in the SCS group than the ICS group. SCS had no effect on BMD, although the frequency of patients at "high-risk" for osteoporosis according to the Female Osteoporosis Self-assessment Tool for Asia (FOSTA) tended to be higher in the SCS group (35%) than in the ICS (28%) or control (10%) group. Because patients in the ICS group already had impaired respiratory function due to repeated asthma exacerbations, it was difficult to determine whether it was asthma itself or SCS that is the risk factor for osteoporosis. In addition, the response of biochemical markers of bone turnover to intermittent SCS remains unclear and likely differs from that elicited by high-dose, short-term, or continuous SCS. That said, relatively low-dose intermittent administration of SCS raised levels of bone resorption markers, which likely reflects altered bone metabolism. Taken together, these findings suggest that, without consideration of its effects on bone, SCS administration should be avoided.


Asunto(s)
Corticoesteroides/administración & dosificación , Corticoesteroides/farmacología , Asma/tratamiento farmacológico , Densidad Ósea/efectos de los fármacos , Huesos/efectos de los fármacos , Adolescente , Corticoesteroides/efectos adversos , Corticoesteroides/uso terapéutico , Agonistas Adrenérgicos beta/uso terapéutico , Adulto , Anciano , Asma/complicaciones , Asma/fisiopatología , Estatura/efectos de los fármacos , Huesos/metabolismo , Colágeno Tipo I/sangre , Femenino , Volumen Espiratorio Forzado/fisiología , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/inducido químicamente , Péptidos/sangre , Factores de Riesgo , Adulto Joven
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