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1.
J Cosmet Dermatol ; 21(11): 6249-6260, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35818134

RESUMO

BACKGROUND: Acne vulgaris is a chronic inflammatory skin disease. If skin lesions are not treated well in time, they can leave a permanent impact on the appearance and a negative influence on personal confidence. The common therapy for acne symptom includes antibiotics, benzoyl peroxide, and azeleic acid. However, those medications have side effects, and the long-term use should be cautious. Therefore, it is necessary to develop a safe and effective material, which is more suitable for daily use. OBJECTIVE: Collagen was selected to co-ferment with three probiotic strains TYCA06/AP-32/CP-9 (TAC) due to its excellent feature on wound healing. The fermented material was added into cosmetic gel and applied on subjects' acne lesions. The antimicrobial activity against Propionibacterium acnes and anti-inflammation effect around lesion area were investigated in a 4-week clinical study. MATERIAL AND METHODS: An anti-P. acnes assay, a keratinocytes HaCaT cell-based wound healing assay, and a cytokine assay on thymic stromal lymphopoietin (TSLP) and interleukin (IL)-33 were used to evaluate the function of the fermented material in vitro. The TAC/Collagen formula was further incorporated into a cosmetic gel, and the human clinical trial was carried out by applying this gel on 20 volunteers' face with acne vulgaris. The moisture score, sebum content, inflammation, porphyrins numbers, and brown spot number of whole face were observed and recorded. RESULTS: The postbiotics of the TAC/Collagen displayed a good growth inhibition against P. acnes and reduced TSLP and IL-33 inflammation in vitro. This TAC/Collagen formula enhanced the wound healing in HaCaT cell culture. The result of the clinical trial showed the TAC/Collagen gel improved the moisture score and inflammation index of the skin in vivo. In addition, this TAC/Collagen gel also improved the wound healing of acne symptom in volunteers with acne vulgaris. Moreover, this TAC/Collagen gel reduced the number of the porphyrins and brown spots on facial skin. CONCLUSION: These postbiotics of TAC/Collagen have beneficial effects on skin health and are able to ameliorate the redness, inflammation, and acne symptom in acne vulgaris patients.


Assuntos
Acne Vulgar , Cosméticos , Fármacos Dermatológicos , Humanos , Acne Vulgar/diagnóstico , Antibacterianos , Peróxido de Benzoíla , Fármacos Dermatológicos/uso terapêutico , Cosméticos/farmacologia , Citocinas , Colágeno/farmacologia , Propionibacterium acnes
2.
Aging (Albany NY) ; 14(5): 2221-2238, 2022 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-35236778

RESUMO

The oral cavity plays a crucial role in food digestion and immune protection. Thus, maintaining oral health is necessary. Postbiotic and heat-killed probiotic cells have shown increased antibacterial potential with stable viability compared with live strains. However, clinical evidence regarding their effect on oral health is insufficient. Therefore, in this study, we tested postbiotic lozenges of Lactobacillus salivarius subsp. salicinius AP-32, L. paracasei ET-66, and L. plantarum LPL28 and heat-killed probiotic lozenges of L. salivarius subsp. salicinius AP-32 and L. paracasei ET-66 for their effect on oral health. In total, 75 healthy individuals were blindly and randomly divided into placebo, postbiotic lozenge, and heat-killed probiotic lozenge groups and were administered the respective lozenge type for 4 weeks. Postbiotic and heat-killed probiotic lozenge groups demonstrated antibacterial activities with a considerable increase in L. salivarius in their oral cavity. Furthermore, their salivary immunoglobulin A, Lactobacillus, and Bifidobacterium increased. Subjective questionnaires completed by the participants indicated that participants in both the experimental groups developed better oral health and intestinal conditions than those in the placebo group. Overall, our study revealed that a food additive in the form of an oral postbiotic or heat-killed probiotic lozenge may effectively enhance oral immunity, inhibit the growth of oral pathogens, and increase the numbers of beneficial oral microbiota.


Assuntos
Temperatura Alta , Probióticos , Antibacterianos , Humanos , Lactobacillus , Higiene Bucal
3.
Oral Dis ; 28(6): 1723-1732, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33749084

RESUMO

OBJECTIVE: Probiotics participate in regulating oral microbiota and reducing the prevalence of oral diseases; however, clinical research on probiotics is insufficient. Therefore, in this study, we performed in vitro screening of potential oral protective probiotic strains and then evaluated the clinical efficacy of the selected strains on maintaining oral health. MATERIALS AND METHODS: Fifty healthy individuals were recruited and randomly assigned into the placebo group and probiotics group, which included three strains of probiotics, Lactobacillus salivarius subs. salicinius AP-32, Lactobacillus paracasei ET-66, and Lactobacillus plantarum LPL28. Each group was blindly administered placebo or probiotics for four weeks. RESULTS: Next-generation sequencing results showed that the oral microbiota of Lactobacillus salivarius in the oral cavity were significantly increased in subjects supplemented with mixed probiotic lozenges. The anti-bacterial activities of viable probiotics were observed within two weeks. Both IgA levels and Lactobacillus and Bifidobacterium abundances in the oral cavity were significantly increased in the experimental groups, along with a reduced formation of plaque. Most participants reported that their oral health conditions and intestinal symptoms had improved. CONCLUSIONS: Overall, our clinical study suggests that oral probiotic lozenges may enhance oral immunity, modulate oral microbiota, and improve oral health.


Assuntos
Placa Dentária , Probióticos , Bifidobacterium/fisiologia , Placa Dentária/microbiologia , Humanos , Imunidade , Lactobacillus/fisiologia , Probióticos/uso terapêutico
4.
Curr Microbiol ; 78(9): 3541-3549, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34345965

RESUMO

Oral-nasal mucosal immunity plays a crucial role in protecting the body against bacterial and viral invasion. Safe probiotic products have been used to enhance human immunity and oral health. In this study, we verified the beneficial effects of mixed viable probiotic tablets, consisting of Lactobacillus salivarius subsp. salicinius AP-32, Bifidobacterium animalis subsp. lactis CP-9, and Lactobacillus paracasei ET-66, and heat-killed probiotic tablets, consisting of L. salivarius subsp. salicinius AP-32 and L. paracasei ET-66, on oral immunity among 45 healthy participants. Participants were randomly divided into viable probiotic, heat-killed probiotic, and placebo groups. The administration of treatment lasted for 4 weeks. Saliva samples were collected at Weeks 0, 2, 4, and 6, and Lactobacillus, Bifidobacterium and Streptococcus mutans populations and IgA concentration were measured. IgA concentrations, levels of TGF-beta and IL-10 in PBMCs cells were quantified by ELISA method. Results showed that salivary IgA levels were significantly increased on administration of both the viable (119.30 ± 12.63%, ***P < 0.001) and heat-killed (116.78 ± 12.28%, ***P < 0.001) probiotics for 4 weeks. Among three probiotic strains, AP-32 would effectively increase the levels of TGF-beta and IL-10 in PBMCs. The oral pathogen Streptococcus mutans was significantly reduced on viable probiotic tablet administration (49.60 ± 31.01%, ***P < 0.001). The in vitro antibacterial test confirmed that viable probiotics effectively limited the survival rate of oral pathogens. Thus, this clinical pilot study demonstrated that oral probiotic tablets both in viable form or heat-killed form could exert beneficial effects on oral immunity via IL-10, TGB-beta mediated IgA secretion. The effective dosage of viable probiotic content in the oral tablet was 109 CFUs/g and the heat-killed oral tablet was 1 × 1010 cells/g.


Assuntos
Probióticos , Método Duplo-Cego , Temperatura Alta , Humanos , Imunoglobulina A , Mucosa Bucal , Projetos Piloto
5.
PeerJ ; 9: e11209, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33986988

RESUMO

BACKGROUND: Uric acid (UA) is the end product of purine metabolism in the liver and is excreted by the kidneys. When purine metabolism is impaired, the serum UA level will be elevated (hyperuricemia) and eventually lead to gout. During evolution, humans and some primates have lost the gene encoding uricase, which is vital in UA metabolism. With the advances of human society, the prevalence of hyperuricemia has dramatically increased because of the refined food culture. Hyperuricemia can be controlled by drugs, such as allopurinol and probenecid. However, these drugs have no preventive effect and are associated with unpleasant side effects. An increasing number of probiotic strains, which are able to regulate host metabolism and prevent chronic diseases without harmful side effects, have been characterized. The identification of probiotic strains, which are able to exert beneficial effects on UA metabolism, will provide an alternative healthcare strategy for patients with hyperuricemia, especially for those who are allergic to anti-hyperuricemia drugs. METHODS: To elicit hyperuricemia, rats in the symptom control group (HP) were injected with potassium oxonate and fed a high-purine diet. Rats in the probiotic groups received the high-purine diet, oxonate injection, and supplements of probiotic strains TSR332, TSF331, or La322. Rats in the blank control group (C) received a standard diet (AIN-93G) and oxonate injection. RESULTS: Purine-utilizing strains of probiotics were screened using high-pressure liquid chromatography (HPLC) in vitro, and the lowering effect on serum UA levels was analyzed in hyperuricemia rats in vivo. We found that Lactobacillus reuteri strain TSR332 and Lactobacillus fermentum strain TSF331 displayed significantly strong assimilation of inosine (90%; p = 0.00003 and 59%; p = 0.00545, respectively) and guanosine (78%; p = 0.00012 and 51%; p = 0.00062, respectively) within 30 min in vitro. Further animal studies revealed that serum UA levels were significantly reduced by 60% (p = 0.00169) and 30% (p = 0.00912), respectively, in hyperuricemic rats treated with TSR332 and TSF331 for 8 days. Remarkably, TSR332 ameliorated the occurrence of hyperuricemia, and no evident side effects were observed. Overall, our study indicates that TSR332 and TSF331 are potential functional probiotic strains for controlling the development of hyperuricemia.

6.
Exp Ther Med ; 21(3): 188, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33488797

RESUMO

Alcoholic steatohepatitis (ASH) is a complex multifactorial disease that can lead to liver fibrosis and cirrhosis if not treated promptly. Alcohol-induced oxidative stress and inflammation are the main factors that cause steatohepatitis and liver injury; however, probiotic bacteria in the gastrointestinal tract have been revealed to regulate immune responses and reduce oxidative stress, suggesting that functional probiotics could help to prevent ASH and liver injury. Despite numerous reports on the interactions between ASH and probiotics, the mechanisms underlying probiotic-mediated liver protection remain unknown. Therefore, the aim of the present study was to screen probiotics with high antioxidant capacity and investigate the ability of different probiotic combinations to reduce alcoholic liver disease (ALD) in a mouse model. It was identified that Lactobacillus plantarum (TSP05), Lactobacillus fermentum (TSF331) and Lactobacillus reuteri (TSR332) neutralized free radicals and displayed high antioxidant activity in vitro. In addition, these three functional probiotic strains protected mice from alcohol-induced liver injury in vivo. Mice treated with the probiotics demonstrated significantly lower alanine aminotransferase, aspartate aminotransferase and triglyceride levels, which were associated with the downregulation of the proinflammatory cytokines TNF-α and IL-6. Furthermore, probiotic treatment upregulated glutathione and glutathione peroxidase activity, which are bioindicators of oxidative stress in the liver. Collectively, the present results indicated that Lactobacillus strains TSP05, TSF331 and TSR332 reduced oxidative stress and inflammatory responses, thus preventing ASH development and liver injury.

7.
Nutrients ; 12(7)2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32630786

RESUMO

Bifidobacterium longum subsp. longum Olympic No. 1 (OLP-01) has been shown in previous animal experiments to improve exercise endurance performance, but this effect has not been confirmed in humans, or more particularly, in athletes. Toward this end, the current study combined OLP-01 supplementation with regular exercise training in well-trained middle- and long-distance runners at the National Taiwan Sport University. The study was designed as a double-blind placebo-controlled experiment. Twenty-one subjects (14 males and seven females aged 20-30 years) were evenly distributed according to total distance (meters) traveled in 12 min to one of the following two groups: a placebo group (seven males and three females) and an OLP-01 (1.5 × 1010 colony forming units (CFU)/day) group (seven males and four females). All the participants received placebo or OLP-01 supplements for five consecutive weeks consisting of three weeks of regular training and two weeks of de-training. Before and after the experiment, the participants were tested for 12-min running/walking distance, and body composition, blood/serum, and fecal samples were analyzed. The results showed that OLP-01 significantly increased the change in the 12-min Cooper's test running distance and the abundance of gut microbiota. Although no significant change in body composition was found, OLP-01 caused no adverse reactions or harm to the participants' bodies. In summary, OLP-01 can be used as a sports nutrition supplement, especially for athletes, to improve exercise performance.


Assuntos
Desempenho Atlético/fisiologia , Bifidobacterium/fisiologia , Resistência Física/fisiologia , Probióticos/administração & dosagem , Corrida/fisiologia , Adulto , Composição Corporal/fisiologia , Método Duplo-Cego , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal/fisiologia , Humanos , Masculino , Placebos , Células-Tronco , Taiwan , Adulto Jovem
8.
Arch Med Sci ; 16(1): 66-70, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32051707

RESUMO

INTRODUCTION: Several works have suggested heightened risk for cardiac events in cocaine users following percutaneous coronary intervention (PCI). Such studies have generally been performed in small, poorly defined samples and have not utilised optimal control groups. We aimed to define the short-term risk for death or recurrent myocardial infarction (MI) when PCI was performed for myocardial infarction in subjects presenting with urine toxicology positive for cocaine in relation to subjects testing negative for cocaine use. MATERIAL AND METHODS: Our institutional electronic health record (EHR) was queried for all subjects with urine toxicology performed for cocaine exposure within 5 days before or after having elevated troponin-T assay between 1/1/08 and 12/31/13. Query results were cross-referenced with our institutional cardiology database to identify the sample who had PCI on the same admission as the cocaine test. Subsequent readmission for MI was assessed from the EHR, and deaths were identified from the National Death Index. RESULTS: PCI had been performed in 380 subjects who tested negative for cocaine and 44 subjects who tested positive. In the cocaine-positive group, incidences of death or MI at 30 days and 1 year were 18% and 23%, respectively. Those who tested positive for cocaine had increased odds (odds ratio (OR) = 2.3, 95% confidence interval (CI): 1.0-5.1, p = 0.04) for death or MI at 30 days post PCI, after adjustment for age, sex, prior MI, and comorbidity index. Although the odds for events 1-year post PCI were not increased (OR = 2.0, 95% CI: 0.9-4.3), the p-value approached significance in this small sample (p = 0.09). CONCLUSIONS: This retrospective study suggests that PCI performed in cocaine-associated myocardial infarction comes with a high 30-day and one-year risk. Further prospective studies are needed to better define this risk and to lend insight into better management strategies.

9.
Int J Cardiol ; 293: 109-114, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31147194

RESUMO

BACKGROUND: Cardiac Resynchronization Therapy Defibrillator (CRT-D) has been one of the most important therapies for patients with cardiomyopathy over the last decades. Cardiac perforation occurs infrequently but can be fatal. The occurrence of cardiac perforation after CRT-D implantation has not been studied well. The aim of study is to investigate the occurrence, mortality and predictors of cardiac perforation in patients receiving CRT-D during the index hospitalization. METHODS: Data were obtained from the National Inpatient Sample, the largest all-player inpatient dataset in the United States. Patients who received CRT-D from 2002 to 2012 were identified using ICD-9 codes. Multivariate analyses were used to identify predictors of cardiac perforation. Complications including in-hospital death and cardiac perforation were identified using ICD-9 codes. RESULTS: A total of 77,827 patients with CRT-D implantation were included into our analysis. After the CRT-D implantation, the in-hospital and rate of cardiac perforation was between 0.24 and 0.48% and had increased significantly (p = 0.02). Although occurrence of cardiac perforation is rare (0.32%), the mortality was 10.6% among those patients with cardiac perforation. In Multivariate analysis identified female as independent risk factors for cardiac perforation (OR: 2.628, 95% CI 1.926-3.585, p < 0.0001). CONCLUSION: Despite rapid progress of the tools and skills for CRT-D implantation, the occurrence of cardiac perforation has not improved. While cardiac perforation is rare, it carries the highest rate of mortality, especially in female patients. Implanting physicians should be familiar with the comorbidities and patient demographics that put them at a higher risk for complications.


Assuntos
Dispositivos de Terapia de Ressincronização Cardíaca/efeitos adversos , Terapia de Ressincronização Cardíaca/efeitos adversos , Terapia de Ressincronização Cardíaca/mortalidade , Traumatismos Cardíacos/mortalidade , Complicações Pós-Operatórias/mortalidade , Sistema de Registros , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia de Ressincronização Cardíaca/tendências , Dispositivos de Terapia de Ressincronização Cardíaca/tendências , Bases de Dados Factuais/tendências , Feminino , Traumatismos Cardíacos/diagnóstico , Traumatismos Cardíacos/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade/tendências , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Valor Preditivo dos Testes , Estados Unidos/epidemiologia , Adulto Jovem
10.
Hu Li Za Zhi ; 62(3 Suppl): 21-9, 2015 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-26074114

RESUMO

BACKGROUND & PROBLEMS: Ventilator-associated pneumonia (VAP) is a common healthcare-associated infection in the intensive care unit. The average VAP rate was .128% in our unit during 2011. Therefore, we designed a project to identify relevant problems, including: inadequate knowledge about VAP care, incorrect techniques for sputum suction, patient head elevation < 30~45 degrees, ventilator humidifier installed with water equipment designed without water-resistant barriers, failure to change the resuscitator and small-volume nebulizer regularly, and possible cross-contamination between respiratory-care devices. PURPOSE: We targeted a VAP rate decrease from the current .128% to less than .1%. RESOLUTION: The improvement measures implemented included team resource management (TRM) with VAP education, promotion, a written reminder regarding sputum accumulation sites, instruction to elevate the head of patients to an appropriate height, introduction of an auto-stop water adding system, and regular changes of related devices at assigned positions. RESULTS: The VAP rate decreased from .128% to .065%. CONCLUSIONS: The risk identification and associated TRM project improved teamwork and the quality of care in the ICU.


Assuntos
Unidades de Terapia Intensiva , Pneumonia Associada à Ventilação Mecânica/prevenção & controle , Recursos em Saúde , Humanos
11.
Plant Cell ; 26(7): 3201-19, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25070640

RESUMO

Plasma membrane-localized pattern recognition receptors such as FLAGELLIN SENSING2 (FLS2) and EF-TU RECEPTOR (EFR) recognize microbe-associated molecular patterns (MAMPs) to activate the first layer of plant immunity termed pattern-triggered immunity (PTI). A reverse genetics approach with genes responsive to the priming agent ß-aminobutyric acid (BABA) revealed IMPAIRED OOMYCETE SUSCEPTIBILITY1 (IOS1) as a critical PTI player. Arabidopsis thaliana ios1 mutants were hypersusceptible to Pseudomonas syringae bacteria. Accordingly, ios1 mutants demonstrated defective PTI responses, notably delayed upregulation of PTI marker genes, lower callose deposition, and mitogen-activated protein kinase activities upon bacterial infection or MAMP treatment. Moreover, Arabidopsis lines overexpressing IOS1 were more resistant to P. syringae and demonstrated a primed PTI response. In vitro pull-down, bimolecular fluorescence complementation, coimmunoprecipitation, and mass spectrometry analyses supported the existence of complexes between the membrane-localized IOS1 and FLS2 and EFR. IOS1 also associated with BRASSINOSTEROID INSENSITIVE1-ASSOCIATED KINASE1 (BAK1) in a ligand-independent manner and positively regulated FLS2/BAK1 complex formation upon MAMP treatment. Finally, ios1 mutants were defective in BABA-induced resistance and priming. This work reveals IOS1 as a regulatory protein of FLS2- and EFR-mediated signaling that primes PTI activation upon bacterial elicitation.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/imunologia , Imunidade Vegetal , Proteínas Quinases/metabolismo , Transdução de Sinais , Aminobutiratos/metabolismo , Arabidopsis/genética , Arabidopsis/imunologia , Proteínas de Arabidopsis/genética , Expressão Gênica , Leucina/metabolismo , Mutação , Doenças das Plantas/microbiologia , Proteínas Quinases/genética , Pseudomonas syringae/fisiologia , Receptores de Reconhecimento de Padrão/genética , Receptores de Reconhecimento de Padrão/metabolismo
12.
Plant Cell ; 24(3): 1256-70, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22427336

RESUMO

Plant cells can be sensitized toward a subsequent pathogen attack by avirulent pathogens or by chemicals such as ß-aminobutyric acid (BABA). This process is called priming. Using a reverse genetic approach in Arabidopsis thaliana, we demonstrate that the BABA-responsive L-type lectin receptor kinase-VI.2 (LecRK-VI.2) contributes to disease resistance against the hemibiotrophic Pseudomonas syringae and the necrotrophic Pectobacterium carotovorum bacteria. Accordingly, LecRK-VI.2 mRNA levels increased after bacterial inoculation or treatments with microbe-associated molecular patterns (MAMPs). We also show that LecRK-VI.2 is required for full activation of pattern-triggered immunity (PTI); notably, lecrk-VI.2-1 mutants show reduced upregulation of PTI marker genes, impaired callose deposition, and defective stomatal closure. Overexpression studies combined with genome-wide microarray analyses indicate that LecRK-VI.2 positively regulates the PTI response. LecRK-VI.2 is demonstrated to act upstream of mitogen-activated protein kinase signaling, but independently of reactive oxygen production and Botrytis-induced kinase1 phosphorylation. In addition, complex formation between the MAMP receptor flagellin sensing2 and its signaling partner brassinosteroid insensitive1-associated kinase1 is observed in flg22-treated lecrk-VI.2-1 mutants. LecRK-VI.2 is also required for full BABA-induced resistance and priming of PTI. Our work identifies LecRK-VI.2 as a novel mediator of the Arabidopsis PTI response and provides insight into molecular mechanisms governing priming.


Assuntos
Proteínas de Arabidopsis/imunologia , Arabidopsis/genética , Imunidade Vegetal , Proteínas Serina-Treonina Quinases/imunologia , Aminobutiratos/farmacologia , Arabidopsis/enzimologia , Arabidopsis/imunologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , DNA Bacteriano/genética , Resistência à Doença , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Teste de Complementação Genética , Mutagênese Insercional , Análise de Sequência com Séries de Oligonucleotídeos , Pectobacterium carotovorum/patogenicidade , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Estômatos de Plantas/imunologia , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Pseudomonas syringae/patogenicidade , RNA de Plantas/genética
14.
Plant J ; 65(3): 469-79, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21265899

RESUMO

The priming agent ß-aminobutyric acid (BABA) is known to enhance Arabidopsis resistance to the bacterial pathogen Pseudomonas syringae pv. tomato (Pst) DC3000 by potentiating salicylic acid (SA) defence signalling, notably PR1 expression. The molecular mechanisms underlying this phenomenon remain unknown. A genome-wide microarray analysis of BABA priming during Pst DC3000 infection revealed direct and primed up-regulation of genes that are responsive to SA, the SA analogue benzothiadiazole and pathogens. In addition, BABA was found to inhibit the Arabidopsis response to the bacterial effector coronatine (COR). COR is known to promote bacterial virulence by inducing the jasmonic acid (JA) response to antagonize SA signalling activation. BABA specifically repressed the JA response induced by COR without affecting other plant JA responses. This repression was largely SA-independent, suggesting that it is not caused by negative cross-talk between SA and JA signalling cascades. Treatment with relatively high concentrations of purified COR counteracted BABA inhibition. Under these conditions, BABA failed to protect Arabidopsis against Pst DC3000. BABA did not induce priming and resistance in plants inoculated with a COR-deficient strain of Pst DC3000 or in the COR-insensitive mutant coi1-16. In addition, BABA blocked the COR-dependent re-opening of stomata during Pst DC3000 infection. Our data suggest that BABA primes for enhanced resistance to Pst DC3000 by interfering with the bacterial suppression of Arabidopsis SA-dependent defences. This study also suggests the existence of a signalling node that distinguishes COR from other JA responses.


Assuntos
Aminoácidos/farmacologia , Aminobutiratos/farmacologia , Arabidopsis/genética , Indenos/farmacologia , Imunidade Vegetal/efeitos dos fármacos , Pseudomonas syringae/patogenicidade , Arabidopsis/imunologia , Arabidopsis/microbiologia , Toxinas Bacterianas/farmacologia , Ciclopentanos/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas/efeitos dos fármacos , Genes de Plantas/genética , Mutação , Análise de Sequência com Séries de Oligonucleotídeos , Oxilipinas/metabolismo , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Estômatos de Plantas/fisiologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/microbiologia , Plantas Geneticamente Modificadas/fisiologia , Pseudomonas syringae/imunologia , Ácido Salicílico/farmacologia , Transdução de Sinais , Tiadiazóis/farmacologia , Regulação para Cima/efeitos dos fármacos
15.
Biomaterials ; 30(27): 4700-7, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19501902

RESUMO

Many different types of magnetic particles have been developed for the purpose of hyperthermia cancer therapy. In this study, a magnetic nanoparticle based on dicalcium phosphate dihydrate (DCPD) was formed by co-precipitation method. Addition of different concentrations of ferrous chloride to DCPD can alter its material properties. Various physical, chemical and magnetic tests of the magnetic DCPD nanoparticles (mDCPD) were performed, including X-ray diffraction (XRD), inductively coupled plasma-optical emission spectrometer (ICP-OES), superconducting quantum interference device (SQUID), and transmission electron microscopy (TEM). The heating efficiency of mDCPD in alternating magnetic field was proved to be suitable for hyperthermia. The results of cytotoxicity tests (WST-1 and LDH assay) showed no harmful effect. The mDCPD showed relative cancer-killing ability without damaging normal cells in vitro.


Assuntos
Fosfatos de Cálcio/farmacologia , Magnetismo , Nanopartículas/química , Temperatura , Animais , Bioensaio , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , L-Lactato Desidrogenase/metabolismo , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/ultraestrutura , Neoplasias/patologia , Tamanho da Partícula , Espectrofotometria Atômica , Sais de Tetrazólio , Fatores de Tempo , Difração de Raios X
16.
Opt Express ; 16(18): 14294-303, 2008 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-18773040

RESUMO

We propose and experimentally demonstrate the generation of single-cycle terahertz radiation with two-stage optical rectification in GaSe crystals. By adjusting the time delay between the pump pulses employed to excite the two stages, the terahertz radiation from the second GaSe crystal can constructively superpose with the terahertz field injected from the first stage. The high mutual coherence between the two terahertz radiation fields is ensured with the coherent optical rectification process and can be further used to synthesize a desired spectral profile of coherent THz radiation. The technique is also potentially useful for generating high-power single-cycle terahertz pulses, usually limited by the pulse walk-off effect of the nonlinear optical crystal used.


Assuntos
Desenho Assistido por Computador , Gálio/química , Interferometria/instrumentação , Iluminação/instrumentação , Refratometria/instrumentação , Selênio/química , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Raios Infravermelhos , Micro-Ondas , Modelos Teóricos
17.
Opt Express ; 14(12): 5484-91, 2006 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-19516714

RESUMO

We reported a type-I difference-frequency generator (DFG), based on erbium doped GaSe (Er:GaSe) crystals as a coherent infrared source tunable from 2.4 mum to 28 mum. The two mixing beams used for the DFG are a tunable near infrared output (1.1-1.8 mum) from an optical parametric amplifier (OPA) and the fundamental beam of a picosecond Nd:YAG laser at 1.064 mum. The system can produce a maximum output pulse energy of 5 microJ at wavelength of 3.5 microm, corresponding to a photon conversion efficiency of 8% at a pump intensity of 1.7 GW/cm(2). The nonlinear coefficient (d(eff)) of 0.5 atom % erbium doped GaSe crystal was found to be 55.3 pm/V or 24 % higher than that of a pure GaSe crystal. The improvement of d(eff) is attributed to the substitutive and interstitial doping of Er ion in GaSe unit cell. The optical properties of GaSe influenced by the erbium doping are also presented.

18.
Opt Express ; 14(22): 10636-44, 2006 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-19529468

RESUMO

We report a study of the effect of optical absorption on generation of coherent infrared radiation from mid-IR to THz region from GaSe crystal. The infrared-active modes of epsilon-GaSe crystal at 236 cm(-1) and 214 cm(-1) were found to be responsible for the observed optical dispersion and infrared absorption edge. Based upon phase matching characteristics of GaSe for difference-frequency generation (DFG), new Sellmeier equations of GaSe were proposed. The output THz power variation with wavelength can be properly explained with a decrease of parametric gain and the spectral profile of absorption coefficient of GaSe. The adverse effect of infrared absorption on (DFG) process can partially be compensated by doping GaSe crystal with erbium ions.

19.
Opt Express ; 14(22): 10930-8, 2006 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-19529506

RESUMO

The population-split genetic algorithm (PSGA) was successfully applied to retrieve femtosecond optical fields from interferometric autocorrelation traces. PSGA strikes a balance between diversity and the size of population in the genetic algorithm. As a result, PSGA is less likely prematurely converging to sub-optimal solutions. Theoretical and experimental studies indicate that the PSGA can yield more accurate results in shorter time compared with conventional genetic algorithm and the iterative method. compared with conventional genetic algorithm and iterative method.

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