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1.
JACC Case Rep ; 29(11): 102355, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38765200

RESUMO

Streptococcus bovis/Streptococcus equinus complex includes the subspecies Streptococcus alactolyticus. The prevalence of systemic infection in humans with S alactolyticus is scarce. We present a case of infective endocarditis complicated with hemorrhagic and ischemic stroke in a healthy 31-year-old woman.

2.
Neurocrit Care ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589692

RESUMO

BACKGROUND: Standard treatment for eligible patients presenting with acute ischemic stroke (AIS) is thrombolysis with tissue plasminogen activators alteplase or tenecteplase. Current guidelines recommend monitoring patients in an intensive care unit (ICU) for 24 h after thrombolytic therapy. However, recent studies have questioned the need for prolonged ICU monitoring. This retrospective cohort study aims to identify potential candidates for early transition to a lower level of care by assessing risk factors for neurological deterioration, symptomatic intracranial hemorrhage (sICH), or need for ICU intervention within 24 h post-thrombolysis. METHODS: This retrospective cohort study included adult patients 18 years and older with AIS who received thrombolysis. Patients were excluded if they were transferred to another facility, if they were transitioned to comfort care or hospice care within 24 h, or if they lacked imaging and National Institutes of Health Stroke Scale (NIHSS) score data. The primary end point was incidence of sICH between 0-12 and 12-24 h. Secondary end points included the need for ICU intervention and rates of neurological deterioration. RESULTS: The analysis included 204 patients who received the full dose of alteplase. Among them, ten patients (4.9%) developed sICH, with the majority (n = 7) occurring within 12 h post-thrombolysis. Sixty-two patients required ICU interventions within 12 h compared with four patients after 12 h. Twenty-four patients had neurological deterioration within 12 h, and seven patients had neurological deterioration after 12 h. Multivariable analysis identified mechanical thrombectomy and increased blood pressure at presentation as predictors of ICU need beyond 12 h post-thrombolysis. CONCLUSIONS: Our study demonstrates that sICH, neurological deterioration, and need for ICU intervention rarely occur beyond 12 h after thrombolytic administration. Patients presenting with blood pressures < 140/90 mm Hg, NIHSS scores < 10, and not undergoing mechanical thrombectomy may be best candidates for early de-escalation. Larger prospective studies are needed to more fully evaluate the safety, feasibility, and financial impact of early transition out of the ICU.

3.
Micromachines (Basel) ; 15(3)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38542543

RESUMO

The surface cleaning of metals plays a pivotal role in ensuring their overall performance and functionality. Dielectric barrier discharge (DBD) plasma, due to its unique properties, has been considered to be a good alternative to traditional cleaning methods. The confinement of DBD plasma in microreactors brings additional benefits, including excellent stability at high pressures, enhanced density of reactive species, reduced safety risks, and less gas and energy consumption. In the present work, we demonstrated a DBD plasma-based method for the degradation of stains from metal surfaces in a microreactor. Aluminum plates with capsanthin stains were used to investigate the influence of operational parameters on the decolorization efficiency, including plasma discharge power, plasma processing time, and O2 content in the atmosphere. The results revealed that an increase in plasma discharge power and plasma processing time together with an appropriate amount of O2 in the atmosphere promote the degradation of capsanthin stains. The optimum processing condition was determined to be the following: plasma power of 11.3 W, processing time of 3 min, and Ar/O2 flow rate of 48/2 sccm. The evolution of composition, morphology, bonding configuration, and wettability of aluminum plates with capsanthin and lycopene stains before and after plasma treatment were systematically investigated, indicating DBD plasma can efficiently degrade stains from the surface of metals without damage. On this basis, the DBD plasma cleaning approach was extended to degrade rhodamine B and malachite green stains from different metals, suggesting it has good versatility. Our work provides a simple, efficient, and solvent-free approach for the surface cleaning of metals.

4.
Neurocrit Care ; 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38379103

RESUMO

BACKGROUND: Elevated intracranial pressure (ICP) is a neurological emergency in patients with acute brain injuries. Such a state requires immediate and effective interventions to prevent potential neurological deterioration. Current clinical guidelines recommend hypertonic saline (HTS) and mannitol as first-line therapeutic agents. Notably, HTS is conventionally administered through central venous catheters (CVCs), which may introduce delays in treatment due to the complexities associated with CVC placement. These delays can critically affect patient outcomes, necessitating the exploration of more rapid therapeutic avenues. This study aimed to investigate the safety and effect on ICP of administering rapid boluses of 3% HTS via peripheral intravenous (PIV) catheters. METHODS: A retrospective cohort study was performed on patients admitted to Sisters of Saint Mary Health Saint Louis University Hospital from March 2019 to September 2022 who received at least one 3% HTS bolus via PIV at a rate of 999 mL/hour for neurological emergencies. Outcomes assessed included complications related to 3% HTS bolus and its effect on ICP. RESULTS: Of 216 3% HTS boluses administered in 124 patients, complications occurred in 8 administrations (3.7%). Pain at the injection site (4 administrations; 1.9%) and thrombophlebitis (3 administrations; 1.4%) were most common. The median ICP reduced by 6 mm Hg after 3% HTS bolus administration (p < 0.001). CONCLUSIONS: Rapid bolus administration of 3% HTS via PIV catheters presents itself as a relatively safe approach to treat neurological emergencies. Its implementation could provide an invaluable alternative to the traditional CVC-based administration, potentially minimizing CVC-associated complications and expediting life-saving interventions for patients with neurological emergencies, especially in the field and emergency department settings.

5.
Polymers (Basel) ; 15(19)2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37836031

RESUMO

Slippery coatings, such as the slippery liquid-infused porous surface (SLIPS), have gained significant attention for their potential applications in anti-icing and anti-fouling. However, they lack durability when subjected to mechanical impact. In this study, we have developed a robust slippery coating by blending polyurethane acrylate (PUA) with methyltriethoxysilane (MTES) and perfluoropolyether (PFPE) in the solvent of butyl acetate. The resulting mixture is homogeneous and allows for uniform coating on various substrates using a drop coating process followed by drying at 160 °C for 3 h. The cured coating exhibits excellent water repellency (contact angle of ~108° and sliding angle of ~8°), high transparency (average visible transmittance of ~90%), exceptional adherence to the substrate (5B rating according to ASTMD 3359), and remarkable hardness (4H on the pencil hardness scale). Moreover, the coating is quite flexible and can be folded without affecting its wettability. The robustness of the coating is evident in its ability to maintain a sliding angle below 25° even when subjected to abrasion, water jetting, high temperature, and UV irradiation. Due to its excellent nonwetting properties, the coating can be employed in anti-icing, anti-graffiti, and anti-sticking applications. It effectively reduces ice adhesion on aluminum substrates from approximately 217 kPa to 12 kPa. Even after 20 cycles of icing and de-icing, there is only a slight increase in ice adhesion, stabilizing at 40 kPa. The coating can resist graffiti for up to 400 cycles of writing with an oily marker pen and erasing with a tissue. Additionally, the coating allows for easy removal of 3M tape thereon without leaving any residue.

6.
Cureus ; 15(9): e45218, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37842403

RESUMO

Posterior reversible encephalopathy syndrome (PRES) is a clinicoradiological syndrome that typically presents with headache, visual disturbances, seizures, and altered consciousness. Its hallmark radiological features involve subcortical white matter lesions on magnetic resonance imaging (MRI), predominantly in the parietal and occipital lobes. While generally reversible with favorable outcomes, a minority of cases may progress to malignant cerebral edema and herniation, resulting in death. We present an unusual case of a 47-year-old woman who developed malignant PRES associated with severe diabetic ketoacidosis (DKA). Despite aggressive medical and surgical treatments, the patient's condition worsened, indicating the potential for devastating outcomes in malignant PRES. This case adds to the limited body of literature that suggests the need for vigilance in monitoring patients with severe glycemic disturbances for neurological complications, such as PRES. It also highlights the importance of early recognition and aggressive management in improving neurological outcomes in malignant PRES. Further research is warranted to understand the underlying mechanisms better and identify optimal treatment strategies for this rare but potentially life-threatening condition.

7.
Front Neurol ; 14: 1195008, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37602250

RESUMO

Introduction: Ondine's curse is a rare respiratory disorder that is characterized by central alveolar hypoventilation (CAH) during sleep. It is most commonly congenital. However, it can also be acquired very rarely. Herein, we report a young survivor who developed CAH following cardiopulmonary arrest. Case presentation: A 35-year-old man was admitted to the Intensive Care Unit following unwitnessed cardiopulmonary arrest. Following resuscitative interventions, he remained comatose. Early diagnostic testing showed elevated neuronal specific enolase (28.7 ng/ml), absent cortical responses on evoked potential testing and MRI evidence of restricted diffusion in the cerebellum, hippocampi, juxtacortical white matter, superior cerebellar peduncles, dorsal pons, dorsolateral medulla, and upper cervical spinal cord. Ten days following admission, the patient remained comatose and underwent tracheostomy. He subsequently began to emerge from coma but had persistent unexplained hypotension and bradypnea necessitating ongoing vasopressor and respiratory support. Repeat MRI on hospital day 40 revealed residual FLAIR hyperintensities in the medulla within the nucleus tractus solitarius (NTS). After being discharged to long-term acute care facility, he was successfully liberated from mechanical ventilation 70 days post arrest. Conclusion: We report the first survivor of cardiopulmonary arrest who was complicated by CAH and hypotension with MRI verified ischemic injury to the bilateral NTS regions. Despite this injury, ventilator and vasopressor dependency resolved over a period of 10 weeks. Our case highlighted the essential functions of NTS in regulating the respiratory and cardiovascular systems.

8.
J Pharm Pract ; : 8971900231167932, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36961745

RESUMO

Background: Anticonvulsant prophylaxis (ACP) for early post-traumatic seizures (PTS) is recommended in patients with traumatic brain injury (TBI). Phenobarbital (PB) may be used to prevent alcohol withdrawal syndrome (AWS) in at-risk patients. The dual-purpose use of PB in the TBI population would allow for consolidation of pharmacotherapy. Objective: The primary objective of this study was to determine the frequency of early PTS in TBI patients at risk of AWS treated with PB as ACP. Secondary objectives included determining rates of over sedation and endotracheal intubation. Methods: Patients received an intravenous (IV) loading dose of PB at 15-20 mg/kg followed by 1 mg/kg every 12 hours for 7 days with a goal level of 15-20 mcg/mL. Medication data, seizure frequency, and episodes of over sedation and endotracheal intubation were collected. Results: Eighty patients were treated with PB over a 1-year period. Thirty-nine patients were analyzed. Median loading dose was 19.9 (Interquartile Range 19.1-20.0) mg/kg with a median post load level of 21.7 mcg/mL (IQR 18.3-25.8) mcg/mL. One patient (2.6%) had electrographic evidence for early PTS. PB was discontinued in 4 (10.3%) patients out of concern for over sedation. One patient required endotracheal intubation after rapid PB loading. Conclusion: The frequency of early PTS was low when PB was used as primary ACP in patients with TBI at risk for AWS. Over sedation is a potential adverse effect that should be considered in the choice of ACP. No conclusions can be drawn as to the effectiveness of PB in preventing AWS.

9.
BMJ Open Qual ; 11(2)2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35534043

RESUMO

ICU readmission is associated with increased mortality, resource utilisation and hospital expenditure. In the general population, respiratory-related event is one of the most common causes of unexpected ICU readmission. Patients with neurological deficits faced an increased risks of ICU readmissions due to impaired mentation, protective reflexes and other factors. A retrospective review revealed that the leading cause of unexpected ICU readmissions in adult neurovascular patients admitted to our hospital was respiratory related. A respiratory therapists-driven assessment-and-treat protocol was developed for proactively assessing and treating adult neurovascular patients. On-duty respiratory therapists assessed all neurovascular patients on admission, assigned a respiratory severity score to each patient and then recommended interventions based on a standardised algorithm.Our quality improvement initiative had no effect on the rate of unexpected ICU readmissions in adult neurovascular patients. When compared with the baseline population, patients enrolled in the intervention group were significantly older ((79, 68-85 years) vs (71, 56-81 years)), but they spent comparable amount of time in the ICU (4.5 vs 4 days, p=0.42). When the respiratory severity score was trended in the intervention group, patients demonstrated significant improvement in their respiratory function, with a greater proportion of patients scoring in the minimal and mild categories and smaller proportion in the moderate category (p<0.01).


Assuntos
Unidades de Terapia Intensiva , Readmissão do Paciente , Adulto , Cuidados Críticos , Humanos , Melhoria de Qualidade , Estudos Retrospectivos
10.
J Cereb Blood Flow Metab ; 42(9): 1579-1596, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35491825

RESUMO

Stroke, including ischemic stroke and hemorrhagic stroke can cause massive neuronal death and disruption of brain structure, which is followed by secondary inflammatory injury initiated by pro-inflammatory molecules and cellular debris. Phagocytic clearance of cellular debris by microglia, the brain's scavenger cells, is pivotal for neuroinflammation resolution and neurorestoration. However, microglia can also exacerbate neuronal loss by phagocytosing stressed-but-viable neurons in the penumbra, thereby expanding the injury area and hindering neurofunctional recovery. Microglia constantly patrol the central nervous system using their processes to scour the cellular environment and start or cease the phagocytosis progress depending on the "eat me" or "don't eat me'' signals on cellular surface. An optimal immune response requires a delicate balance between different phenotypic states to regulate neuro-inflammation and facilitate reconstruction after stroke. Here, we examine the literature and discuss the molecular mechanisms and cellular pathways regulating microglial phagocytosis, their resulting effects in brain injury and neural regeneration, as well as the potential therapeutic targets that might modulate microglial phagocytic activity to improve neurological function after stroke.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Isquemia Encefálica/metabolismo , Humanos , Microglia/metabolismo , Neurônios/metabolismo , Fagocitose , Acidente Vascular Cerebral/metabolismo
11.
Cerebellum ; 21(1): 55-63, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33977497

RESUMO

The variability in motor dysfunction is not uncommon in autoimmune disorders. Antibody-mediated system-wide malfunction or effects on the neural network shared by two independent pathophysiological processes can cause such heterogeneity. We tested this prediction for motor dysfunction during gaze holding in 11 patients with increased titers of glutamic acid decarboxylase (anti-GAD) antibody. High-resolution oculography measured horizontal and vertical eye positions. The analysis was performed with customized signal processing algorithms. Downbeat and gaze-evoked nystagmus commonly coexisted; one patient had a combination of upbeat and gaze-evoked nystagmus. The nystagmus was associated with saccadic intrusions in 10 patients; all had squarewaves, but five also had saccadic oscillations. The nystagmus and saccadic intrusions, both in the same axis of eye rotations, were not uncommon. Tandem appearance of the episodes of nystagmus and saccadic intrusions suggested a coupling between the two abnormalities. We speculated a unifying framework where the anti-GAD antibody inhibited (GAD mediated) conversion of glutamate to gamma-aminobutyric acid (GABA). Paucity GABA and excess of glutamate cause nystagmus (less GABA) and high-frequency saccadic oscillations (excessive glutamate).


Assuntos
Doenças do Sistema Imunitário , Nistagmo Patológico , Transtornos da Motilidade Ocular , Glutamato Descarboxilase , Humanos , Doenças do Sistema Imunitário/complicações , Movimentos Sacádicos
12.
Front Neurol ; 12: 727754, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34603185

RESUMO

Introduction: Takotsubo cardiomyopathy (TCM) or "stress cardiomyopathy" is an uncommon condition characterized by transient cardiac dysfunction with left ventricular apical ballooning in an appropriate clinical context. TCM has been observed in a variety of acute neurological conditions most prominently in patients with aneurysmal subarachnoid hemorrhage and status epilepticus. TCM has only been reported infrequently in association with traumatic brain injury (TBI). Herein we present a patient who developed TCM 3 days after hospital admission with severe TBI. Case Presentation: A 30-year-old male presented to the hospital with an acute subdural hematoma, anisocoria, declining consciousness and CT evidence of uncal herniation after being found down in a hotel room. The patient was taken emergently to the operating room for decompressive hemicraniectomy and hematoma evacuation. On the post-trauma day (PTD) 3, the patient developed acute dyspnea with increased oxygen requirements that improved with diuresis. On PTD 4, nursing staff noted T waive inversions (TWI) on the bedside monitor prompting an electrocardiogram (ECG) that showed a prolonged QTc interval and worsening TWI in leads I, II, aVL, and V2-6. Troponin I level was mildly elevated at 0.63ng/mL. Transthoracic echocardiography (TTE) was subsequently performed and showed a low ejection fraction (EF 26%) with apical hypokinesis and basal hyperkinesis, consistent with TCM. A diagnosis of TCM was confirmed by Cardiology consultation and he was started on a beta-blocker and an ACE inhibitor. Follow-up TTE on PTD 20 showed a normal left ventricular EF. Conclusion: While rarely reported in patients with TBI, TCM developed in an otherwise healthy young male following severe TBI necessitating decompressive hemicraniectomy. TTE should be considered in patients with TBI who have cardio-pulmonary symptoms or unexplained ECG abnormalities.

13.
ACS Omega ; 6(11): 7266-7274, 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33778241

RESUMO

A superhydrophobic coating endows pristine hydrophilic wood with excellent water/moisture repellency and thus prolongs its service life. Generally, the superhydrophobic coating on wood is fabricated by a two-step process in which the nanoparticles are first introduced onto the surface and then modified by low-surface-energy molecules. Herein, for the first time, we have fabricated the superhydrophobic wood via a one-step process free of nanoparticles by immersing the pristine hydrophilic wood, such as pine, balsawood, and basswood, into a composite silane solution of hexadecyltrimethoxysilane and methyltrimethoxysilane. The wood remains superhydrophobic or highly hydrophobic after long-term exposure to mechanical damage (such as abrading, knife-cutting, and tape-peeling), chemical damage (such as immersion in acid, alkali, or ethanol), and environmental impacting (such as UV irradiation and low/high-temperature exposure).

15.
Materials (Basel) ; 13(21)2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33143059

RESUMO

In this work, a method of imparting hydrophobicity and high strength to hardened cement paste (HCP) is proposed. Sodium laurate (SL) was used as a hydrophobic modifier and nano silica (NS) as a pozzolan. The HCP was modified by SL and NS simultaneously. HCP modified with different contents of SL and NS was prepared. Surface wettability, micro-structures, chemical composition, and organic structure were systematically studied using contact angle (CA) measurement, scanning electron microscope (SEM) observation, X-ray photoelectron spectroscopy (XPS), and attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), respectively. The surface CA of the sample is 138.5° and has high hydrophobicity. Compared with the reference sample, the water absorption of the modified sample reduced by 96.55%, while the compressive strength only reduced by 6.91%. Therefore, using hydrophobic modifier and reinforcing agent as cement admixture is an effective method to endow concrete with hydrophobicity and high strength at the same time.

16.
Materials (Basel) ; 13(15)2020 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-32759689

RESUMO

In this work, magnesium oxychloride cement (MOC) was used to realize the resource use of foundry dust (FD). Portland cement (PC)-based superhydrophobic coating was prepared on the surface of FD/MOC composite to improve the water resistance of the composite. First, the FD/MOC composites with different contents of FD were prepared. The phase structure of the composite was analyzed using X-ray diffraction (XRD). The microstructure of the cross-section and surface of the composite was observed using field emission scanning electron microscope (FE-SEM). The mechanical properties of the FD/MOC composites with different FD contents at different ages were tested and analyzed. Secondly, the superhydrophobic coating was prepared on the surface of MOC composite using silane/siloxane aqueous emulsion as the hydrophobic modifier, PC as the matrix and water as the solvent. The microstructure and chemical composition of the PC-based superhydrophobic coating were tested and analyzed. The results show that FD can significantly improve the early strength of the FD/MOC composite. The 28-day compressive strength of the FD/MOC composite decreases with increasing FD content. When the FD content is 30%, the 28-day compressive strength of the FD/MOC composite is as high as 75.68 MPa. Superhydrophobic coating can effectively improve the water resistance of the FD/MOC composite. The softening coefficient of the FD/MOC composite without superhydrophobic coating is less than 0.26, while that of the composite modified by superhydrophobic coating is greater than 0.81.

17.
Langmuir ; 36(17): 4664-4670, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32279500

RESUMO

Switchable surface-active colloid particles are critical to the preparation of switchable Pickering emulsions, which are widely involved in multitudinous fundamental and practical fields, such as biomedical, food products, and spinning cosmetics. The stability of switchable surface-active particles relies on the full understanding of interaction forces between individual colloid particles quantitatively. In this work, a dual-laser optical tweezers instrument was applied to measure the interaction forces between silica particles coated with a common cationic surfactant (cetyltrimethylammonium bromide, CTAB) in water, and all of the measured forces can be well fitted with the theoretical model derived from the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. It was revealed that the minimum surface distance to engender the interaction forces between silica particles was closer progressively with the increase of CTAB concentrations, suggesting that the introduction of CTAB molecules in the solution thinned the electric double layer. In addition, the minimum surface distance between surface-inactive silica particles further decreased compared to surface-active states, although the ζ-potential has returned to the initial value of bare silica in pure water when the molecular ratio of 1:1 anionic surfactant (sodium dodecyl sulfate, SDS) was added into the solution to switch the surface-active silica particles to surface-inactive states. Our results provide a considerate methodology for quantifying the interaction forces and investigating the switchable behaviors of CTAB molecules from the adsorption to desorption at the particle-water interfaces, which provide vital foresights into the stabilization mechanism of switchable surface-active colloid particles and the further development of switchable Pickering emulsions.

19.
Materials (Basel) ; 12(11)2019 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-31181832

RESUMO

The main aim of this study is to evaluate the possibility of applying foundry dust (FD) derived filler for the preparation of natural rubber (NR) based composites by characterizing the mechanical properties. The as-received FD was processed via a simple and low-cost procedure, including sieving, deironing and milling using a variety of industrial equipment. FD powders before and after silane coupling agent (Si 69) modification were used as fillers for NR. NR composites inserted with different content of modified and unmodified FD up to 50 phr were prepared via dry-mixing method. Then, comprehensive mechanical performances were performed on the corresponding vulcanizates. It was demonstrated that NR composite filled with 50 phr of modified FD exhibited optimized comprehensive mechanical performance. Tear strength and hardness is increased by 21.3% and 12.8% than pure NR, respectively. Tensile strength is reduced by 21% and elongation at break remained nearly unchanged. Additionally, the composite showed a large increment of 50.9% for its wet grip property, while exhibited an increment of only 11.9% for its rolling resistance in comparison with the composite containing 10 phr of FD. The findings of this study may provide a new application area for the large amounts of utilization of foundry waste with a high level of value being added.

20.
J Exp Bot ; 67(15): 4647-58, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27353280

RESUMO

We previously identified the W-box-like-4 (Wbl-4) element (GTAGTGACTCAT), one of six Wbl elements in the BjC-P promoter of the unusual chitinase gene BjCHI1 from Brassica juncea, as the core element responsive to fungal infection. Here, we report the isolation and characterization of the cognate transcription factor interacting with the Wbl-4 element. Using Wbl-4 as a target, we performed yeast one-hybrid screening of a B. juncea cDNA library and isolated an R2R3-MYB transcription factor designated as BjMYB1. BjMYB1 was localized in the nucleus of plant cells. EMSA assays confirmed that BjMYB1 binds to the Wbl-4 element. Transiently expressed BjMYB1 up-regulated the activity of the BjC-P promoter through its binding to the Wbl-4 element in tobacco (Nicotiana benthamiana) leaves. In B. juncea, BjMYB1 displayed a similar induced expression pattern as that of BjCHI1 upon infection by the fungus Botrytis cinerea Moreover, heterogeneous overexpression of BjMYB1 significantly elevated the resistance of transgenic Arabidopsis thaliana to the fungus B. cinerea These results suggest that BjMYB1 is potentially involved in host defence against fungal attack through activating the expression of BjCHI1 by binding to the Wbl-4 element in the BjC-P promoter. This finding demonstrates a novel DNA target of plant MYB transcription factors.


Assuntos
Quitinases/metabolismo , Resistência à Doença/fisiologia , Mostardeira/metabolismo , Proteínas de Plantas/fisiologia , Fatores de Transcrição/fisiologia , Arabidopsis/microbiologia , Arabidopsis/fisiologia , Botrytis/fisiologia , Regulação da Expressão Gênica de Plantas/fisiologia , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/fisiologia , Nicotiana/metabolismo
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