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1.
Biochem Biophys Res Commun ; 704: 149660, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38428303

RESUMEN

Soybean is an economically important crop, which often suffers various abiotic stresses. REVEILLE (RVE) genes have been generally considered as circadian oscillators to mediate diverse developmental processes and plant response to environmental stresses. Addressing their roles is of significance for utilizing them to enhance agronomic traits in crops. However, our understanding of soybean RVEs is extremely limited. In the study, we investigated the expression patterns of soybean CCA1-like genes under salt stress using our RNA-Seq data. Subsequently, a salt stress-inducible gene, GmRVE8a, was chosen for further study. Phylogenetic analysis indicated that GmRVE8a is most closely related to Arabidopsis RVE4 and RVE8. Also, GmRVE8a showed circadian expression pattern with 24 h rhythmic period, suggesting that it might be a clock-regulated gene. Moreover, transgenic Arabidopsis lines over-expressing GmRVE8a were generated. It was observed that ectopic over-expression of GmRVE8a caused a significant delay in flowering. Further observation indicated that under salt and drought stress, transgenic seedlings were stronger than wild type. Consistently, three-week-old transgenic plants grew better than wild type under salt and drought conditions, and the MDA content in transgenic lines was significantly lower than wild type, suggesting that GmRVE8a might be a positive regulator in response to salt and drought stress. Intriguingly, Y2H assay indicated that GmRVE8a physically interacted with a drought-tolerant protein, GmNAC17. Overall, our findings provided preliminary information regarding the functional roles of GmRVE8a in response to salt and drought stress.


Asunto(s)
Arabidopsis , Glycine max , Glycine max/genética , Arabidopsis/metabolismo , Resistencia a la Sequía , Filogenia , Estrés Salino/genética , Estrés Fisiológico/genética , Plantas Modificadas Genéticamente/genética , Sequías , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
2.
J Craniofac Surg ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38958949

RESUMEN

OBJECTIVE: To compare the range of endoscopic and microscopic exposure of the petroclival core area through the middle skull base and to observe the corresponding anatomical structures. METHODS: Ten intact adult cadaveric head specimens fixed with formaldehyde were craniotomized through an expanded middle skull base epidural approach on 20 sides. The distance from the greater superficial petrosal nerve to the petrous ridge was measured. When different degrees (1-3 degrees) of the Kawase triangle bone were removed, the exposed anatomical structure was observed, and the exposed core area of the rock slope was measured under an endoscope and microscope. RESULTS: The average distance from the greater superficial petrosal nerve to the petrous ridge was 14.26 mm. During 1 to 2 degrees of bone removal, the petrous segment of the internal carotid artery (ICA) was not exposed, whereas during 3 degrees of bone removal, the petrous segment of the ICA was exposed. At 1 degree of bone removal, 400.62 ± 15.73 mm2 of the area was exposed by endoscopy and 170.87 ± 8.93 mm2 by microscopy, and the abducens nerve was not exposed. However, there was a significant difference between the two areas (P < 0.001). During 2 degrees of bone removal, 689.30 ± 32.06 mm2 of the abducens nerve was exposed by endoscopy, but 366.84 ± 30.30 mm2 of the abducens nerve could not be exposed by microscopy; moreover, there was a significant difference in the area of exposure between the two (P < 0.001). At 3 degrees of bone removal, the endoscopic exposure area was 875.92 ± 31.87 mm2, the microscopic exposure area was 699.26 ± 48.00 mm2, and the abducens nerves were exposed. There were significant differences between the two areas (P < 0.001). However, the difference between the 2-degree endoscopic exposure area and the 3-degree microscopic exposure area was studied by using paired t tests, and there was no difference (P > 0.05). CONCLUSION: When the same degree of the Kawase triangle bone was removed, the extent of endoscopic exposure of the petroclival core area was significantly greater than the extent of microscopic exposure. At 2 degrees of bone removal, an endoscopic application can maximally expose the petroclival core area, thus reducing the probability of exposure damage to the ICA and abductor nerve.

3.
J Asian Nat Prod Res ; : 1-10, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38996034

RESUMEN

Three new diterpenoid alkaloids (1, 2, 3) and seventeen known (4-20) compounds were isolated from the whole plant of Delphinium sherriffii Munz (Ranunculaceae). Their structures were elucidated by various spectroscopic analyses, including IR, HR-ESI-MS, 1D and 2D NMR spectra. All compounds were evaluated for the inhibitory activity of Sf9 cells and compound 5 exhibited the strongest cytotoxicity (IC50 = 8.97 µM) against Sf9 cell line.

4.
J Org Chem ; 88(3): 1403-1410, 2023 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-36656018

RESUMEN

A nickel-catalyzed three-component tandem radical cyclization reaction of aryl bromides with 1,3-enynes and aryl boric acids to construct γ-lactam-substituted allene derivatives has been described. This protocol provides lactam alkyl radicals through the free radical cyclization process, which can be effectively used to participate in the subsequent multicomponent coupling reaction so that 1,3-enynes could directly convert into corresponding poly-substituted allene compounds. In addition, this efficient method enjoys a broad substrate scope and provides a series of 1,5-difunctionalized allenes in a one-pot reaction.

5.
Nanotechnology ; 34(48)2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37647874

RESUMEN

Isotope engineering has been shown to be an effective means of regulating thermal conductivity. In this work, we studied the isotope engineering of thermal conductivity in bulk and 2D GaN, and diametrically opposite atom isotope dependence is found. That is, Ga isotope has a large effect (77%) on bulk GaN, while the effect of N isotope on the thermal conductivity is negligible. In 2D GaN, however, N isotope effect (20%) is more significant than that of Ga. Understanding of the different isotope dependence is achieved by deeper insight. Due to the relative magnitude of scattering rate, isotopic scattering influences the thermal conductivity of bulk and 2D GaN in different frequency regions, leading to the opposite atom dependence.

6.
Cost Eff Resour Alloc ; 21(1): 1, 2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36635702

RESUMEN

BACKGROUND: Image-guided system (IGS) has been gradually applied in the field of rhinology, making functional endoscopic sinus surgery (FESS) a truly minimally invasive and precise surgery. This study was based on real-world data from China hospitals and aimed to evaluate the clinical and economic benefits of the IGS navigation system in FESS. METHODS: This was a two-center retrospective chart review of patients with chronic rhinosinusitis who underwent FESS, including open frontal sinus between July 1, 2018 and December 31, 2019 in China. The intervention group consisted of 100 patients who underwent FESS with the IGS navigation system (IGS group), and the control group consisted of 100 patients who underwent conventional FESS (Non-IGS group). Data were collected from surgical notes and hospital medical records. The primary endpoints for clinical effectiveness and safety were avoid rehospitalization due to bleeding, avoid reoperation due to bleeding, and avoid reoperation due to recurrence. RESULTS: There were no cases of rehospitalization due to bleeding, reoperation due to bleeding, and reoperation due to recurrence in the IGS group, with an avoidance rate of 100%. In the non-IGS group, there were four cases of rehospitalization and reoperation due to bleeding, with an avoidance rate 96.00% (P = 0.121). No cases of reoperation due to recurrence were in the non-IGS group. The total hospitalization cost was 17,391.51 CNY in the IGS group and 17,742.41 CNY in the non-IGS group per patient, with no statistical difference between the two groups (P = 0.715). Compared with the non-IGS group, the IGS group had an overall cost saving of 350.90 CNY per patient. Although the procedure-related medical costs of IGS group were increased by 1,286.12 CNY compared with the non-IGS group, this was more than offset by other costs. CONCLUSION: The results of the study indicated that the IGS may avoid occurrence of rehospitalization and reoperation due to postoperative bleeding. Although the use of navigation technology increased the cost of surgery, its clinical effectiveness brought other medical cost savings, resulting in no significant difference in the overall cost of navigation surgery compared to conventional surgery. The IGS should be considered cost-effectiveness in the treatment of FESS.

7.
Opt Lett ; 47(21): 5525-5528, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37219260

RESUMEN

Ti2AlC is a kind of ternary layered structured ceramic metal compound, combining the advantages of both ceramic and metal. Herein, the saturable absorption performance of Ti2AlC at the 1-µm wave band is investigated. The Ti2AlC behaves with excellent saturable absorption, which has a modulation depth of 14.53% and a saturable intensity of 13.27 MW/cm2. An all-normal dispersion fiber laser based on the Ti2AlC saturable absorber (SA) is constructed. The repetition frequency of the Q switched pulses increased from 44 to 49 kHz as the pump power rose from 276 to 365 mW, and the corresponding pulse width decreased from 3.64 to 2.42 µs. The maximum output single Q switched pulse energy is as high as 169.8 nJ. Our experiments prove that the MAX phase Ti2AlC has potential as a low-cost, simple preparation, and broadband SA material. To the best of our knowledge, this is the first demonstration of Ti2AlC serving as a SA material achieving Q switched operation at the 1-µm wave band.

8.
Phys Chem Chem Phys ; 23(39): 22423-22429, 2021 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-34585691

RESUMEN

The indirect bandgap of two-dimensional GaN hinders its application in the optical field. Hydrogenation can convert the bandgap type of the GaN monolayer from an indirect to a direct one and also tune the bandgap size. The thermal transport, an important property in the application of two-dimensional materials, is also influenced by hydrogenation. By performing first-principles calculations and solving the phonon Boltzmann equation, we investigate the effect of hydrogenation on the thermal conductivity of the GaN monolayer. The results show that hydrogenation will slightly increase the thermal conductivity of the GaN monolayer from 70.62 Wm-1 K-1 to 76.23 Wm-1 K-1 at 300 K. The little effect of hydrogenation on thermal conductivity is mainly dominated by two competing factors: (1) the reduction of ZA mode lifetime due to the breaking of reflection symmetry after hydrogenation and (2) the increased contribution from TA and LA modes due to the reduction of anharmonic scattering caused by the enlarged phonon bandgap after hydrogenation. The results are compared with other two-dimensional materials with hexagonal monolayer structures.

9.
Appl Opt ; 60(24): 7214-7222, 2021 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-34613009

RESUMEN

In the dairy farming industry, we can obtain the temperature, color, and location information of dairy cows by patrol inspection robot so as to monitor the health status and abnormal behaviors of dairy cows. We build and calibrate a heterogeneous binocular stereo vision (HBSV) system comprising a high-definition color camera and infrared thermal camera and mount it on a patrol inspection robot. First, based on the traditional chessboard, an easy-to-make calibration board for the HBSV system is designed. Second, an accurate locating and sorting algorithm for the calibration points of the calibration board is designed. Then, the cameras are calibrated and the HBSV system is stereo-calibrated. Finally, target locating is achieved based on the above calibration results and Yolo target detection technology. In this paper, several experiments are carried out from many aspects. The target locating average error of HBSV system is 3.11%, which satisfies the needs of the dairy farming environment. The video's FPS captured by using HBSV is 7.3, which is 78% higher than that by using binocular stereo vision system and infrared thermal camera. The results show that the HBSV system has application value to a certain degree.


Asunto(s)
Percepción de Profundidad/fisiología , Fotograbar/instrumentación , Visión Binocular/fisiología , Algoritmos , Calibración , Diseño de Equipo , Imagenología Tridimensional , Robótica/instrumentación
10.
Curr Genet ; 66(2): 345-359, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31422448

RESUMEN

Verticillium dahliae, a soil-borne fungus, can invade plant vascular tissue and cause Verticillium wilt. The enzyme α-oxoglutarate dehydrogenase (OGDH), catalyzing the oxidation of α-oxoglutarate in the tricarboxylic acid cycle (TCA), is vital for energy metabolism in the fungi. Here, we identified the OGDH gene in V. dahliae (VdOGDH, VDAG_10018) and investigated its function in virulence by generating gene deletion mutants (ΔVdOGDH) and complementary mutants (ΔVdOGDH-C). When the ΔVdOGDH mutants were supplemented with different carbon sources, vegetative growth on Czapek Dox medium was significantly impaired, suggesting that VdOGDH is crucial for vegetative growth and carbon utilization. Conidia of the ΔVdOGDH mutants were atypically rounded or spherical, and hyphae were irregularly branched and lacked typical whorled branches. Mutants ΔVdOGDH-1 and ΔVdOGDH-2 were highly sensitive to H2O2 in the medium plates and had higher intracellular ROS levels. ΔVdOGDH mutants also had elevated expression of oxidative response-related genes, indicating that VdOGDH is involved in response to oxidative stress. In addition, the disruption of VdOGDH caused a significant increase in the expression of energy metabolism-related genes VdICL, VdICDH, VdMDH, and VdPDH and melanin-related genes Vayg1, VdSCD, VdLAC, VT4HR, and VaflM in the ΔVdOGDH mutants; thus, VdOGDH is also important for energy metabolism and melanin accumulation. Cotton plants inoculated with ΔVdOGDH mutants exhibited mild leaf chlorosis and the disease index was lower compared with wild type and ΔVdOGDH-C strains. These results together show that VdOGDH involved in energy metabolism of V. dahliae, is also essential for full virulence by regulating multiple fungal developmental factors.


Asunto(s)
Oxidorreductasas/metabolismo , Verticillium/enzimología , Factores de Virulencia/metabolismo , Metabolismo Energético , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica , Peróxido de Hidrógeno/metabolismo , Peróxido de Hidrógeno/toxicidad , Especies Reactivas de Oxígeno/metabolismo , Verticillium/metabolismo , Verticillium/patogenicidad
11.
Int J Geriatr Psychiatry ; 34(4): 513-521, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30623504

RESUMEN

OBJECTIVE: Benzodiazepines and benzodiazepine-related drugs (BZRDs) are used to treat various psychiatric diseases. However, there are concerns that BZRDs increase the risk of pneumonia. METHODS: We performed a systematic review and meta-analysis of observational studies to determine whether BZRD use affects the risk of pneumonia. Our analysis included all observational studies that compared pneumonia development among patients receiving BZRD vs those with no treatment. RESULTS: In total, 12 citations of 10 studies involving more than 120,000 pneumonia cases were included in our meta-analysis. After pooling the estimates, the odds for developing pneumonia were 1.25-fold higher (odd ratio, OR = 1.25; 95% confidence interval (CI), 1.09-1.44) in BZRD users compared with individuals who had not taken BZRD. On the basis of exposure window, we found an increased risk of pneumonia among current (OR = 1.4; 95%CI, 1.22-1.6) and recent (OR = 1.38; 95%CI, 1.06-1.8) users, but not with the past users (OR = 1.11; 95%CI, 0.96-1.27). CONCLUSION: Current or recent exposure to BZRD is associated with an increased pneumonia risk. Clinicians need to weight the benefit-risk balance of BZRD use, especially those with other risk factors for pneumonia.


Asunto(s)
Benzodiazepinas , Hipnóticos y Sedantes , Neumonía , Benzodiazepinas/efectos adversos , Peso Corporal , Humanos , Hipnóticos y Sedantes/efectos adversos , Trastornos Mentales/tratamiento farmacológico , Oportunidad Relativa , Neumonía/inducido químicamente , Medición de Riesgo , Factores de Riesgo
12.
Int J Mol Sci ; 20(2)2019 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-30654456

RESUMEN

Cyclophilins (CYPs) are a member of the immunophilin superfamily (in addition to FKBPs and parvulins) and play a significant role in peptidyl-prolyl cis-trans isomerase (PPIase) activity. Previous studies have shown that CYPs have important functions in plants, but no genome-wide analysis of the cotton CYP gene family has been reported, and the specific biological function of this gene is still elusive. Based on the release of the cotton genome sequence, we identified 75, 78, 40 and 38 CYP gene sequences from G. barbadense, G. hirsutum, G. arboreum, and G. raimondii, respectively; 221 CYP genes were unequally located on chromosomes. Phylogenetic analysis showed that 231 CYP genes clustered into three major groups and eight subgroups. Collinearity analysis showed that segmental duplications played a significant role in the expansion of CYP members in cotton. There were light-responsiveness, abiotic-stress and hormone-response elements upstream of most of the CYPs. In addition, the motif composition analysis revealed that 49 cyclophilin proteins had extra domains, including TPR (tetratricopeptide repeat), coiled coil, U-box, RRM (RNA recognition motif), WD40 (RNA recognition motif) and zinc finger domains, along with the cyclophilin-like domain (CLD). The expression patterns based on qRT-PCR showed that six CYP expression levels showed greater differences between Xinhai21 (long fibres, G. barbadense) and Ashmon (short fibres, G. barbadense) at 10 and 20 days postanthesis (DPA). These results signified that CYP genes are involved in the elongation stage of cotton fibre development. This study provides a valuable resource for further investigations of CYP gene functions and molecular mechanisms in cotton.


Asunto(s)
Fibra de Algodón , Ciclofilinas/genética , Regulación de la Expresión Génica de las Plantas , Genoma de Planta , Gossypium/crecimiento & desarrollo , Gossypium/genética , Familia de Multigenes , Proteínas de Plantas/genética , Cromosomas de las Plantas/genética , Genes de Plantas , Filogenia , Proteínas de Plantas/metabolismo , Regiones Promotoras Genéticas/genética , Especificidad de la Especie
13.
J Craniofac Surg ; 29(3): e287-e290, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29419591

RESUMEN

OBJECTIVE: The aim of the study was to explore the values and disadvantages of micromirror in the intracranial aneurysm clipping surgery. METHODS: Micromirror was used to assist microsurgical clipping to 36 intracranial aneurysms in 31 patients, of which 3 were carotid-ophthalmic artery aneurysms, 3 were anterior choroidal artery aneurysms, 11 were posterior communicating artery aneurysms, 7 were middle cerebral artery aneurysms, 10 were anterior communicating artery or anterior cerebral artery aneurysms, and the rest were a posterior cerebral artery aneurysm and a posterior inferior cerebellar artery aneurysm. The micromirror was used before and after clipping to observe the anatomic features of necks hidden behind and medial to aneurysms, to visualize surrounding neurovascular structures, and to verify the optimal clipping position. Intraoperative indocyanine green fluorescein angiography, postoperative computerized tomography angiography, and digital subtraction angiography confirmed the success of sufficient clipping. RESULTS: Intraoperative indocyanine green angiography, postoperative computerized tomography angiography , or digital subtraction angiography were performed and showed no case of wrong or insufficient clipping of aneurysm. CONCLUSIONS: Micromirror-assisted microsurgical clipping to the intracranial aneurysm is safe, sufficient, convenient, and practical.


Asunto(s)
Angiografía Cerebral , Aneurisma Intracraneal , Procedimientos Neuroquirúrgicos , Cirugía Asistida por Computador , Procedimientos Quirúrgicos Vasculares , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/cirugía
14.
Neurol Neurochir Pol ; 52(1): 25-28, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-28964406

RESUMEN

OBJECTIVE: Pericallosal artery aneurysms are not common clinically. The microsurgery and endovascular therapy are surgically challenging operations. The objective of the study is to summarize their clinical symptoms and optimal treatment strategies of pericallosal artery aneurysms. METHODS: Nine cases of pericallosal artery aneurysms detected by digital subtraction angiography (DSA) were reviewed. The clinical manifestation, brain imaging characteristics, and optimal treatment methods were summarized. RESULTS: Patients with spontaneous aneurysm had good clinical outcomes after endovascular coiling or microsurgical clipping treatment. There were no any neurological function deficits in five patients. One patient suffered from permanent neurological function deficits. Patients with traumatic aneurysm pericallosal had relatively poor outcomes, including two patients showing disturbed consciousness and the paralysis of the lower limbs with slow recovery, and one patient was dead after the surgery. CONCLUSION: Spontaneous subarachnoid hemorrhage and interhemispheric fissure hematoma suggest spontaneously pericallosal aneurysm, while traumatic corpus callosum hematoma as well the accompanying embryo of intraventricular hemorrhage suggest traumatic pericallosal aneurysm. Endovascular embolization is the primary surgical treatment for pericallosal aneurysm, while patients with pericallosal aneurysm are not suitable for surgical treatment. Microsurgical clipping treatment may be a choice. However, both of these treatment strategies have high risk.


Asunto(s)
Arterias , Aneurisma Roto , Embolización Terapéutica , Humanos , Aneurisma Intracraneal , Resultado del Tratamiento
15.
BMC Plant Biol ; 17(1): 101, 2017 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-28595571

RESUMEN

BACKGROUND: Cotton (Gossypium spp.) is the most important fiber and oil crop in the world. With the emergence of huge -omics data sets, it is essential to have an integrated functional genomics database that allows worldwide users to quickly and easily fetch and visualize genomic information. Currently available cotton-related databases have some weakness in integrating multiple kinds of -omics data from multiple Gossypium species. Therefore, it is necessary to establish an integrated functional genomics database for cotton. DESCRIPTION: We developed CottonFGD (Cotton Functional Genomic Database, https://cottonfgd.org ), an integrated database that includes genomic sequences, gene structural and functional annotations, genetic marker data, transcriptome data, and population genome resequencing data for all four of the sequenced Gossypium species. It consists of three interconnected modules: search, profile, and analysis. These modules make CottonFGD enable both single gene review and batch analysis with multiple kinds of -omics data and multiple species. CottonFGD also includes additional pages for data statistics, bulk data download, and a detailed user manual. CONCLUSION: Equipped with specialized functional modules and modernized visualization tools, and populated with multiple kinds of -omics data, CottonFGD provides a quick and easy-to-use data analysis platform for cotton researchers worldwide.


Asunto(s)
Bases de Datos Genéticas , Gossypium/genética , Predicción , Marcadores Genéticos , Variación Genética , Genoma de Planta , Almacenamiento y Recuperación de la Información , Internet , Anotación de Secuencia Molecular
16.
Plant Biotechnol J ; 15(12): 1622-1629, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28418615

RESUMEN

Glyphosate-resistant (GR) crops have been adopted on a massive scale by North and South American farmers. Currently, about 80% of the 120 million hectares of the global genetically modified (GM) crops are GR crop varieties. However, the adoption of GR plants in China has not occurred at the same pace, owing to several factors including, among other things, labour markets and the residual effects of glyphosate in transgenic plants. Here, we report the co-expression of codon-optimized forms of GR79 EPSPS and N-acetyltransferase (GAT) genes in cotton. We found five times more resistance to glyphosate with 10-fold reduction in glyphosate residues in two pGR79 EPSPS-pGAT co-expression cotton lines, GGCO2 and GGCO5. The GGCO2 line was used in a hybridization programme to develop new GR cottons. Field trials at five locations during three growing seasons showed that pGR79-pGAT transgenic cotton lines have the same agronomic performance as conventional varieties, but were USD 390-495 cheaper to produce per hectare because of the high cost of conventional weed management practices. Our strategy to pyramid these genes clearly worked and thus offers attractive promise for the engineering and breeding of highly resistant low-glyphosate-residue cotton varieties.


Asunto(s)
3-Fosfoshikimato 1-Carboxiviniltransferasa/genética , Acetiltransferasas/genética , Glicina/análogos & derivados , Gossypium/genética , Resistencia a los Herbicidas/genética , Regulación de la Expresión Génica de las Plantas , Ingeniería Genética/métodos , Glicina/farmacocinética , Glicina/farmacología , Gossypium/efectos de los fármacos , Herbicidas/farmacocinética , Herbicidas/farmacología , Plantas Modificadas Genéticamente , Nicotiana/genética , Glifosato
17.
Remote Sens Environ ; 196: 76-88, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32848282

RESUMEN

Stereogrammetry applied to globally available high resolution spaceborne imagery (HRSI; < 5 m spatial resolution) yields fine-scaled digital surface models (DSMs) of elevation. These DSMs may represent elevations that range from the ground to the vegetation canopy surface, are produced from stereoscopic image pairs (stereopairs) that have a variety of acquisition characteristics, and have been coupled with lidar data of forest structure and ground surface elevation to examine forest height. This work explores surface elevations from HRSI DSMs derived from two types of acquisitions in open canopy forests. We (1) apply an automated mass-production stereogrammetry workflow to along-track HRSI stereopairs, (2) identify multiple spatially coincident DSMs whose stereopairs were acquired under different solar geometry, (3) vertically co-register these DSMs using coincident spaceborne lidar footprints (from ICESat-GLAS) as reference, and (4) examine differences in surface elevations between the reference lidar and the co-registered HRSI DSMs associated with two general types of acquisitions (DSM types) from different sun elevation angles. We find that these DSM types, distinguished by sun elevation angle at the time of stereopair acquisition, are associated with different surface elevations estimated from automated stereogrammetry in open canopy forests. For DSM values with corresponding reference ground surface elevation from spaceborne lidar footprints in open canopy northern Siberian Larix forests with slopes < 10°, our results show that HRSI DSMs acquired with sun elevation angles > 35° and < 25° (during snow-free conditions) produced characteristic and consistently distinct distributions of elevation differences from reference lidar. The former include DSMs of near-ground surfaces with root mean square errors < 0.68 m relative to lidar. The latter, particularly those with angles < 10°, show distributions with larger differences from lidar that are associated with open canopy forests whose vegetation surface elevations are captured. Terrain aspect did not have a strong effect on the distribution of vegetation surfaces. Using the two DSM types together, the distribution of DSM-differenced heights in forests (µ = 6.0 m, σ = 1.4 m) was consistent with the distribution of plot-level mean tree heights (µ = 6.5 m, σ = 1.2 m). We conclude that the variation in sun elevation angle at time of stereopair acquisition can create illumination conditions conducive for capturing elevations of surfaces either near the ground or associated with vegetation canopy. Knowledge of HRSI acquisition solar geometry and snow cover can be used to understand and combine stereogrammetric surface elevation estimates to co-register and difference overlapping DSMs, providing a means to map forest height at fine scales, resolving the vertical structure of groups of trees from spaceborne platforms in open canopy forests.

18.
J Med Virol ; 88(4): 614-21, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26381060

RESUMEN

Henan, China is characterized by the outbreak of HIV epidemic of Thai B strain in former plasma donors in 1990s. After the forbidden of paid blood donation, whether Thai B strain will spread out of former plasma donors into sexual transmitted population is unknown. To answer the question, phylogenetic analysis was used to explore relationships of HIV strains circulating in those two populations in the study. HIV-1 sero-positive drug-naïve patients infected through sexual contact were enrolled into the study. Full length gag and pol genes were amplified with nested RT-PCR followed by sequencing and phylogenetic analysis. The genotypes of anti-HIV drug resistance were also analyzed with available pol genes. HIV subtypes were determined in 249 individuals from 288 participants. Subtype B was dominant (202/249, 81.1%), followed by CRF01_AE (25/249, 10.0%), CRF07_BC (14/249, 5.6%), C (4/249, 1.6%), URF (3/249, 1.2%), and CRF08_BC (1/249, 0.4%). Most of subtype B strains belong to Thailand B lineage. All of Thai B strains identified in sexual transmitted population intermixed with those from former blood donors in phylogenetic tree, suggesting close phylogenetic relationship between strains epidemic in those two populations. TDR was identified in 9.9% individuals. Thai B strain has spread out of former blood donors in Henan province. The finding will contribute to understanding the distribution and evolution of HIV-1 in Henan province and also provide clue to behavior change intervention.


Asunto(s)
Donantes de Sangre , Brotes de Enfermedades , Transmisión de Enfermedad Infecciosa , Genotipo , Infecciones por VIH/epidemiología , VIH-1/clasificación , VIH-1/genética , Adolescente , Adulto , China/epidemiología , Estudios Epidemiológicos , Femenino , Infecciones por VIH/transmisión , Infecciones por VIH/virología , VIH-1/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Tailandia/epidemiología , Adulto Joven , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/genética
19.
J Environ Biol ; 37(5): 881-8, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-29251473

RESUMEN

Genetically modified crops (GMCs) hold great promise for improving agricultural output, but at the same time present challenges in terms of environmental safety assessment. Ammonia oxidizers, including ammonia oxidizing bacteria (AOB) and archaea (AOA), are very important functional microbial groups in nitrogen cycle. The abundance and diversity of AOA and AOB in the rhizosphere of genetically modified cotton (SGK321) and non-GM cotton (SY321) across growth stages were investigated using real time quantitative PCR (qPCR) and terminal restriction fragment length polymorphism (T-RFLP). Results showed that cotton genotype had a significant effect on the change in abundance of AOA and AOB, as indicated by amoA copy number. Variations in AOB abundance in rhizosphere of SY321 differed from those in SGK321. The number of AOB in the rhizosphere of SY321 fluctuated considerably: It dramatically decreased from 1.2?106 copies g-1 dry soil to 3?105 copies g-1 dry soil during the flowering stage and then increased to 1.1?106 copies g-1 and 1.5?106 copies g-1 at the belling and boll opening stages, respectively. However, abundance of AOB in the rhizosphere of SGK321 was relatively stable during all the stages of growth. The effect of SGK321 and SY321 on AOA number was quite similar to that of AOB: AOA abundance in SGK321 increased smoothly from 1.0 ?105 copies g-1 dry soil to 1.4?106 copies g-1 dry soil during growth, but that in SY321 fluctuated. Correspondence analysis (CA), canonical CA (CCA), and partial CCA (pCCA) of T-RFLP profiles of AOA and AOB showed that AOB community changed across growth stages in both cotton genotypes, and cotton genotype was the most important factor affecting the AOA community. In conclusion, the current findings indicated no adverse effect of GM cotton on functional microorganisms.


Asunto(s)
Amoníaco/metabolismo , Archaea/metabolismo , Bacterias/metabolismo , Gossypium/genética , Microbiología del Suelo , Archaea/clasificación , Bacterias/clasificación , ADN de Archaea/genética , ADN Bacteriano/genética , Oxidación-Reducción , Raíces de Plantas , Plantas Modificadas Genéticamente , Suelo
20.
AIDS Res Ther ; 12: 22, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26120348

RESUMEN

BACKGROUND: In Henan, China, first-line antiretroviral treatment (ART) was implemented early in a large number of treatment-experienced patients who were more likely to have a drug resistance. Therefore, we investigated the human immunodeficiency virus (HIV)-1 drug resistance profiles among patients in Henan who experienced virological failure to ART. METHOD: A cross-sectional survey was administered in 10 major epidemic cities from May 2010 to October 2011. Adult patients who experienced virological failure (virus load ≥1,000 copies/mL) with >1 year of first-line antiretroviral treatment consented to provide blood for genotype resistance testing. The clinical and demographic data were obtained from the patients' medical records. Logistic regression analysis was performed to determine the factors associated with ≥1 significant drug resistance mutation. RESULTS: We included 3,235 patients with integral information and valid genotypic resistance data. The city, age, CD4 counts, virus load, treatment duration, and World Health Organization stage were associated with drug resistance, and 64.76% of patients acquired drug resistance. The nucleoside reverse transcriptase inhibitor (NRTI), non-(N)NRTI, and protease inhibitor resistance mutations were found in 50.26, 63.12, and 1.30% of subjects, respectively. Thymidine analogue mutations, NNRTI and even multidrug resistance complex were quite common in this patient cohort. CONCLUSION: Multiple and complex patterns of HIV-1 drug resistance mutations were identified among individuals who experienced virological failure to first-line ART in Henan, China during 2010-2011. Therefore, timely virological monitoring, therapy adjustments, and more varieties of drugs and individualized treatment should be immediately considered in this patient population.

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