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1.
BMC Plant Biol ; 23(1): 141, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36915047

RESUMEN

BACKGROUND: The WRKY transcription factors play significant roles in plant growth, development, and defense responses. However, in cotton, the molecular mechanism of most WRKY proteins and their involvement in Verticillium wilt tolerance are not well understood. RESULTS: GhWRKY70 is greatly up-regulated in cotton by Verticillium dahliae. Subcellular localization suggests that GhWRKY70 is only located in the nucleus. Transcriptional activation of GhWRKY70 further demonstrates that GhWRKY70 function as a transcriptional activator. Transgenic Arabidopsis plants overexpressing GhWRKY70 exhibited better growth performance and higher lignin content, antioxidant enzyme activities and jasmonic acid (JA) levels than wild-type plants after infection with V. dahliae. In addition, the transgenic Arabidopsis resulted in an enhanced expression level of AtAOS1, a gene related to JA synthesis, further leading to a higher JA accumulation compared to the wild type. However, the disease index (DI) values of the VIGS-treated cotton plants with TRV:WRKY70 were also significantly higher than those of the VIGS-treated cotton plants with TRV:00. The chlorophyll and lignin contents of TRV:WRKY70 plants were significantly lower than those of TRV:00 plants. GhAOS1 expression and JA abundance in TRV:WRKY70 plants were decreased. The GhWRKY70 protein was confirmed to bind to the W-box element in the promoter region of GhAOS by yeast one-hybrid assay and transient expression. CONCLUSION: These results indicate that the GhWRKY70 transcription factor is a positive regulator in Verticillium wilt tolerance of cotton, and may promote the production of JA via regulation of GhAOS1 expression.


Asunto(s)
Resistencia a la Enfermedad , Gossypium , Enfermedades de las Plantas , Factores de Transcripción , Verticillium , Arabidopsis/genética , Arabidopsis/metabolismo , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas , Gossypium/genética , Gossypium/metabolismo , Lignina/metabolismo , Enfermedades de las Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Verticillium/patogenicidad , Plantas Modificadas Genéticamente
2.
Electrophoresis ; 43(3): 464-471, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34611912

RESUMEN

We developed a low-cost polymer-film spiral inertial microfluidic device for the effective size-dependent separation of malignant tumor cells. The device was fabricated in polymer films by rapid laser cutting and chemical bonding. After fabricating the prototype device, the separation performance of our device was evaluated using particles and cells. The effects of operational flow rate, cell diameter, and cell concentration on the separation performance were explored. Our device successfully separated tumor cells from polydisperse white blood cells according to their different migration modes and lateral positions. Then, the separation of rare cells was carried out using the high-concentration lysed blood spiked with 200 tumor cells. Experimental results showed that 83.90% of the tumor cells could be recovered, while 99.87% of white blood cells could be removed. We successfully employed our device for processing clinical pleural effusion samples from patients with advanced metastatic breast cancer. Malignant tumor cells with an average purity of 2.37% could be effectively enriched, improving downstream diagnostic accuracy. Our device offers the advantages of label-free operation, low cost, and fast fabrication, thus being a potential tool for effective cell separation.


Asunto(s)
Técnicas Analíticas Microfluídicas , Neoplasias , Separación Celular , Humanos , Dispositivos Laboratorio en un Chip , Microfluídica , Polímeros
3.
J Acoust Soc Am ; 150(1): 225, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34340515

RESUMEN

The sound-transmission, beam-formation, and sound-reception processes of a short-finned pilot whale (Globicephala macrorhynchus) were investigated using computed tomography (CT) scanning and numerical simulation. The results showed that sound propagations in the forehead were modulated by the upper jaw, air components, and soft tissues, which attributed to the beam formation in the external acoustic field. These structures owned different acoustic impedance and formed a multiphasic sound transmission system that can modulate sounds into a beam. The reception pathways composed of the solid mandible and acoustic fats in the lower head conducted sounds into the tympano-periotic complex. In the simulations, sounds were emitted in the forehead transmission system and propagated into water to interrogate a steel cylinder. The resulting echoes can be interpreted from multiple perspectives, including amplitude, waveform, and spectrum, to obtain the acoustic cues of the steel cylinder. By taking the short-finned pilot whale as an example, this study provides meaningful information to further deepen our understanding of biosonar system operations, and may expand sound-reception theory in odontocetes.


Asunto(s)
Ballena de Aleta , Calderón , Acústica , Animales , Sonido , Espectrografía del Sonido
4.
Electrophoresis ; 34(2): 260-8, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23161242

RESUMEN

Based on the investigation of the effect of microemulsion charge on the chiral separation, a new chiral separation method with MEEKC employing neutral microemulsion was established. The method used a microemulsion containing 3.0% (w/v) neutral surfactant Tween 20 and 0.8% (w/v, 30 mM) dibutyl l-tartrate in 40 mM sodium tetraborate buffer to separate the enantiomers of ß-blockers. The effect of major parameters on the chiral separation was investigated. The applied voltage had little effect on the resolution, but the chiral separation could be improved by suppressing the EOF. Nine racemic ß-blockers obtained relatively good enantioseparation after appropriate concentrations of tetradecyl trimethyl ammonium bromide were added into the microemulsion to suppress the EOF. These results were explained based on the analysis of the separation mechanism of the method and deduced separation equations. The resolution equation of the method was further elucidated. It was found that the fourth term in the resolution equation, an additional term compared to the conventional resolution equation for column chromatography, represents the ratio of the relative movement distance between the analyte and microemulsion droplets relative to the effective capillary length. It can be regarded as a correction for the effective capillary length. These findings are significant for the development of the theory of MEEKC and the development of new chiral MEEKC method.


Asunto(s)
Antagonistas Adrenérgicos beta/aislamiento & purificación , Cromatografía Capilar Electrocinética Micelar/métodos , Antagonistas Adrenérgicos beta/química , Boratos/química , Campos Electromagnéticos , Electroósmosis , Emulsiones/química , Polisorbatos/química , Propanolaminas/química , Propanolaminas/aislamiento & purificación , Estereoisomerismo , Tensoactivos/química , Tartratos/química
5.
Integr Zool ; 16(4): 440-450, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33259136

RESUMEN

A pioneering boat-based survey was conducted in 2019, to gather baseline information regarding the presence, composition, relative abundance, and spatial distribution of deep-diving and off-shore cetaceans in the northern South China Sea (SCS). A total of 27 sightings comprising at least 8 cetacean species were recorded during the 13-day survey, including 5 deep-diving species (i.e. Risso's dolphin [Grampus griseus], short-finned pilot whale [Globicephala macrorhynchus], sperm whale [Physeter macrocephalus], Cuvier's beaked whale [Ziphius cavirostris], and an unidentified beaked whale [either the ginkgo-toothed beaked whale, Mesoplodon ginkgodens, or Deraniyagala's beaked whale, Mesoplodon hotaula]), as well as 3 off-shore dolphins (i.e. pantropical spotted dolphin [Stenella attenuate], striped dolphin [Stenella coeruleoalba], and Fraser's dolphin [Lagenodelphis hosei]). With the exception of pantropical spotted dolphins, all other species were sighted and recorded at sea in the northern SCS for the first time. The pantropical spotted dolphin was the most frequently sighted species, comprising 30% of the total sightings. Deep-diving cetaceans were mainly sighted in the northern Xisha Archipelago, whereas off-shore dolphins were distributed across the survey area. The pantropical spotted dolphin was observed in aggregations of more than 100 individuals and nearly all encountered species included calves; these findings suggested that the survey area functions as an important feeding and calving ground for various cetacean species. This pioneering survey provides fundamental information regarding cetacean fauna in the northern SCS and highlights the need to strengthen research and conservation efforts concerning these species.


Asunto(s)
Cetáceos , Animales , Ecosistema , Femenino , Masculino , Océano Pacífico
6.
Integr Zool ; 16(4): 451-461, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33289310

RESUMEN

Beaked whales represent around 25% of known extant cetacean species, yet they are the least known of all marine mammals. Identification of many Mesoplodon species has relied on examination of a few stranded individuals. Particularly, the ginkgo-toothed beaked whale (Mesoplodon ginkgodens) and Deraniyagala's beaked whale (Mesoplodon hotaula) are among the least-known of beaked whale species, without confirmed sightings of living individuals to date. We present a sighting of 3 free-ranging individuals of M. ginkgodens/hotaula whale from a dedicated marine mammal vessel survey carried out in the South China Sea in April and May 2019. Photographic data (301 photographs) from the sighting were compared to photos of fresh stranded ginkgo-toothed beaked whale and Deraniyagala's beaked whale from both historical and unpublished records. We found that free-ranging M. ginkgodens and M. hotaula individuals can be easily distinguished from other Mesoplodon species due to differences in melon and gape shapes and coloration patterns. However, accurate at-sea differentiation of M. ginkgodens and M. hotaula may not be possible due to high similarity in both coloration and scarring patterns. In addition to our photo-identification data, we collected what we believe to be the first preliminary descriptions of surfacing behavior and diving patterns of one of these species. Finally, the presence of scars possibly caused by fishing gear or marine litter raises concerns about anthropogenic impacts and conservation of these poorly known species.


Asunto(s)
Ballenas/anatomía & histología , Animales , Conducta Animal , Buceo , Océano Pacífico , Ballenas/clasificación , Ballenas/fisiología
7.
J Acoust Soc Am ; 128(3): 1476-82, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20815482

RESUMEN

Data on distribution, abundance, ecology, and behavior are essential for conservation and management of endangered animals in the wild. Yangtze finless porpoise (Neophocaena phocaenoides asiaeorientalis) is an endangered small odontocete species, living exclusively in the Yangtze River and its connecting Poyang and Dongting Lakes. Frequent production of high-frequency bio-sonar signals allows the animal to be detectable using passive acoustic methods. Recently, a stereo acoustic event data-logger (A-tag) has been used extensively to detect the animal by using both fixed and mobile platforms. The passive acoustic monitoring methods were not only successful in detecting the presence of animals, but also in counting, localizing, and tracking phonating individuals. Underwater behavior observed acoustically helped to assess possible effects of vessels on the animals during acoustic surveys.


Asunto(s)
Acústica/instrumentación , Densidad de Población , Marsopas/fisiología , Vocalización Animal , Animales , China , Especies en Peligro de Extinción , Diseño de Equipo , Miniaturización
8.
iScience ; 23(10): 101640, 2020 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-33103078

RESUMEN

The Indo-Pacific humpback dolphin (Sousa chinensis) is a small inshore species of odontocete cetacean listed as Vulnerable on the IUCN Red List. Here, we report on the evolution of S. chinensis chromosomes from its cetruminant ancestor and elucidate the evolutionary history and population genetics of two neighboring S. chinensis populations. We found that breakpoints in ancestral chromosomes leading to S. chinensis could have affected the function of genes related to kidney filtration, body development, and immunity. Resequencing of individuals from two neighboring populations in the northwestern South China Sea, Leizhou Bay and Sanniang Bay, revealed genetic differentiation, low diversity, and small contemporary effective population sizes. Demographic analyses showed a marked decrease in the population size of the two investigated populations over the last ~4,000 years, possibly related to climatic oscillations. This study implies a high risk of extinction and strong conservation requirement for the Indo-Pacific humpback dolphin.

9.
Talanta ; 76(2): 246-53, 2008 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-18585272

RESUMEN

In this study the interaction between gallic acid and human serum albumin (HSA) in AOT/isooctane/water microemulsions was characterized for the first time using fluorescence quenching technique in combination with UV absorption spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, circular dichroism (CD) spectroscopy and dynamic light scattering (DLS) technique. In water-surfactant molar ratio (omega(o))=20 microemulsions fluorescence data revealed the presence of one binding site of gallic acid on HSA and its binding constants (K) were (1.18+/-0.02)x10(4), (1.13+/-0.02)x10(4), (1.03+/-0.02)x10(4), (0.95+/-0.02)x10(4), (0.87+/-0.02)x10(4) and (0.82+/-0.03)x10(4)M(-1) at 282, 289, 296, 303, 310 and 317 K, respectively. The affinities in microemulsions were much higher than that in buffer solution. FT-IR and CD data suggested that the protein conformations were altered with the reductions of alpha-helices from 54-56% for free HSA in buffer to 40-41% for free HSA in microemulsion. After binding with gallic acid, the alpha-helices of HSA in microemulsion increased 2-7% for different drug-protein molar ratio. The thermodynamic functions standard enthalpy (Delta H(0)) and standard entropy (DeltaS(0)) for the reaction were calculated to be -8.10 kJ mol(-1) and 49.42 J mol(-1)K(-1). These results indicated that gallic acid bound to HSA mainly by hydrophobic interaction and electrostatic interaction in microemulsions. In addition, the displacement experiments confirmed that gallic acid could bind to the site I of HSA, which was approved by the molecular modeling study. Furthermore, the DLS data suggested that HSA may locate at the interface of the microemulsion and gallic acid could interact with them.


Asunto(s)
Ácido Gálico/química , Albúmina Sérica/química , Sitios de Unión , Emulsiones , Humanos , Membranas Artificiales , Unión Proteica , Conformación Proteica , Soluciones , Análisis Espectral
10.
J Fluoresc ; 18(3-4): 661-70, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18297375

RESUMEN

The interaction between bergenin and human serum albumin (HSA) in AOT/isooctane/water microemulsions was studied by fluorescence quenching technique in combination with UV absorption spectroscopy, circular dichroism (CD) spectroscopy and dynamic light scattering (DLS) technique. Fluorescence data in omega (o) 20 microemulsions revealed the presence of a binding site of bergenin on HSA and its binding constants (K) were 1.64 x 10(4), 1.44 x 10(4), 1.26 x 10(4) and 1.09 x 10(4) M(-1) at 289, 296, 303, and 310 K, respectively. The binding of bergenin with HSA in microemulsions was stronger than that in buffer solution. The alterations of protein secondary structure in the microemulsions in the absence and presence of bergenin compared with the free form of HSA in buffer were qualitatively and quantitatively analyzed by the evidence from CD spectra. Enthalpy and entropy changes for the reaction were calculated to be -14.45 kJ mol(-1) and 30.76 J mol(-1) K(-1). These results indicated that bergenin bound to HSA mainly by a hydrophobic interaction in microemulsions which was in agreement with the result of the molecular modeling study. The DLS data suggested that HSA may locate at the interface of the microemulsion and bergenin could interact with them.


Asunto(s)
Benzopiranos/química , Membranas Artificiales , Albúmina Sérica/química , Benzopiranos/metabolismo , Sitios de Unión , Dicroismo Circular , Emulsiones/química , Polarización de Fluorescencia , Humanos , Luz , Modelos Moleculares , Octanos/química , Preparaciones de Plantas/química , Unión Proteica , Dispersión de Radiación , Albúmina Sérica/metabolismo , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Succinatos/química , Termodinámica , Agua/química
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