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1.
Mol Phylogenet Evol ; 197: 108106, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38750675

RESUMO

The Hildenbrandiales, a typically saxicolous red algal order, is an early diverging florideophycean group with global significance in marine and freshwater ecosystems across diverse temperature zones. To comprehensively elucidate the diversity, phylogeny, biogeography, and evolution of this order, we conducted a thorough re-examination employing molecular data derived from nearly 700 specimens. Employing a species delimitation method, we identified Evolutionary Species Units (ESUs) within the Hildenbrandiales aiming to enhance our understanding of species diversity and generate the first time-calibrated tree and ancestral area reconstruction for this order. Mitochondrial cox1 and chloroplast rbcL markers were used to infer species boundaries, and subsequent phylogenetic reconstructions involved concatenated sequences of cox1, rbcL, and 18S rDNA. Time calibration of the resulting phylogenetic tree used a fossil record from a Triassic purportedly freshwater Hildenbrandia species and three secondary time points from the literature. Our species delimitation analysis revealed an astounding 97 distinct ESUs, quintupling the known diversity within this order. Our time-calibration analysis placed the origin of Hildenbrandiales (crown age) in the Ediacaran period, with freshwater species emerging as a monophyletic group during the later Permian to early Triassic. Phylogenetic reconstructions identified seven major clades, experiencing early diversification during the Silurian to Carboniferous period. Two major evolutionary events-colonization of freshwater habitats and obligate systemic symbiosis with a marine fungus-marked this order, leading to significant morphological alterations without a commensurate increase in species diversification. Despite the remarkable newly discovered diversity, the extant taxon diversity appears relatively constrained when viewed against an evolutionary timeline spanning over 800 million years. This limitation may stem from restricted geographic sampling or the prevalence of asexual reproduction. However, species richness estimation and rarefaction analyses suggest a substantially larger diversity yet to be uncovered-potentially four times greater. These findings drastically reshape our understanding of the deeply diverging florideophycean order Hildenbrandiales species diversity, and contribute valuable insights into this order's evolutionary history and ecological adaptations. Supported by phylogenetic, ecological and morphological evidence, we established the genus Riverina gen. nov. to accommodate freshwater species of Hildenbrandiales, which form a monophyletic clade in our analyses. This marks the first step toward refining the taxonomy of the Hildenbrandiales, an order demanding thorough revisions, notably with the creation of several genera to address the polyphyletic status of Hildenbrandia. However, the limited diagnostic features pose a challenge, necessitating a fresh approach to defining genera. A potential solution lies in embracing a molecular systematic perspective, which can offer precise delineations of taxonomic boundaries.


Assuntos
Filogenia , Rodófitas , Simbiose , Simbiose/genética , Rodófitas/genética , Rodófitas/classificação , Filogeografia , Rios , Análise de Sequência de DNA , Teorema de Bayes , Biodiversidade , Evolução Molecular , Evolução Biológica , RNA Ribossômico 18S/genética
2.
Front Plant Sci ; 12: 700413, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34589095

RESUMO

The antioxidant glutathione (GSH) mitigates adverse physio-metabolic effects and defends against abiotic types of stress, such as cadmium (Cd) stress. However, its function and role in resisting Cd phytotoxicity by leveraging plant antioxidant-scavenging, redox-regulating, and hormone-balancing systems have not been comprehensively and systematically demonstrated in the Cd-hyperaccumulating plant Brassica napus L. cv. Tammi (oilseed rape). In this study, the effects of exogenously applied GSH to the leaves of B. napus seedlings exposed to Cd (10 µM) were investigated. As a result, Cd stress alone significantly inhibited growth and increased the levels of reactive oxygen species (ROS) and the bioaccumulation of Cd in the seedlings compared with those in unstressed controls. Furthermore, Cd stress induced an imbalance in plant stress hormone levels and decreases in endogenous GSH levels and GSH redox ratios, which were correlated with reductions in ascorbate (AsA) and/or nicotinamide adenine dinucleotide phosphate (NADPH) redox states. However, the exogenous application of GSH to Cd-stressed B. napus seedlings reduced Cd-induced ROS levels and enhanced antioxidant-scavenging defenses and redox regulation by both increasing seedling AsA, GSH, and NADPH concentrations and rebalancing stress hormones, thereby enhancing Cd uptake and accumulation. These results demonstrate that GSH improved plant redox status by upregulating the AsA-GSH-NADPH cycle and reestablishing normal hormonal balance. This indicates that exogenously applied GSH can mitigate Cd phytotoxicity in B. napus and possibly other plants. Therefore, GSH can potentially be applied to Cd-polluted soil for plant remediation.

3.
Front Plant Sci ; 11: 586547, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33329648

RESUMO

The role of ascorbate (AsA) in antioxidant defense system-associated resistance to cadmium (Cd) in oilseed rape plants has not yet been clearly demonstrated. The present study investigated the critical role of exogenous AsA on the physiological and biochemical responses of reactive oxygen species (ROS) and antioxidant scavenging defense systems in oilseed rape (Brassica napus L. cv. Tammi) seedlings exposed to Cd. Cd (10 µM) treatment led to significant reductions in plant growth; increases in the levels of superoxide anion radical, hydrogen peroxide, and malondialdehyde; and increases in Cd uptake and accumulation by the roots and shoots in hydroponically grown 10-day-old seedlings. Moreover, it reduced AsA content and AsA redox ratios, which have been correlated with reductions in glutathione (GSH) and/or nicotinamide adenine dinucleotide phosphate (NADPH) redox status. However, exogenously applying AsA to Cd-exposed seedlings decreased Cd-induced ROS, improved antioxidant defense systems by increasing AsA, GSH, and NADPH contents, and increased Cd uptake and accumulation in both roots and shoots of the plants. These results provided evidence that the enhancement in AsA redox status can be linked to an increase in the GSH and/or NADPH redox ratios through the induction of the AsA-GSH-NADPH cycle. Thus, these results suggest that exogenous AsA application to oilseed rape seedlings under Cd stress might alleviate the overall Cd toxicity by regulating the homeostasis of the AsA-GSH-NADPH cycle, which reestablishes the steady-state cellular redox status.

4.
Biomolecules ; 9(10)2019 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-31614510

RESUMO

Flumequine is a well-known second generation quinolone antibiotic that induces phototoxicity. However, the effect of flumequine on skin melanogenesis is unclear. Therefore, we, for the first time, investigated whether flumequine regulates melanogenesis. The present study showed that flumequine slightly inhibited in vitro mushroom tyrosinase activity but significantly increased extracellular and intracellular melanin content in B16F10 cells and promoted the expression of microphthalmia-associated transcription factor (MITF) and tyrosinase. Additionally, flumequine remarkably increased melanin pigmentation in zebrafish larvae without any toxicity. We also found that flumequine stimulated p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK) phosphorylation; inhibition of p38 MAPK and JNK resulted in significant downregulation of extracellular and intracellular melanin content in B16F10 cells and pigmentation of zebrafish larvae accompanied with suppression of MITF and tyrosinase expression, indicating that flumequine-mediated p38 and JNK promote melanogenesis in vitro and in vivo. According to the molecular docking prediction, flumequine targeted dual-specificity MAPK phosphatase 16 (DUSP16), which is a major negative regulator of p38 MAPK and JNK. Our findings demonstrate that flumequine induces an increase in melanin content in B16F10 cells and zebrafish larvae by activating p38 MAPK and JNK. These data show the potential of flumequine for use as an anti-vitiligo agent.


Assuntos
Antibacterianos/farmacologia , Fluoroquinolonas/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Larva/efeitos dos fármacos , Pele/efeitos dos fármacos , Peixe-Zebra/crescimento & desenvolvimento , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Agaricales/enzimologia , Animais , Antibacterianos/química , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Fluoroquinolonas/química , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Larva/citologia , Larva/enzimologia , Melaninas/antagonistas & inibidores , Melaninas/biossíntese , Camundongos , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Pele/metabolismo , Células Tumorais Cultivadas , Regulação para Cima/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
5.
Yonsei Med J ; 56(1): 295-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25510778

RESUMO

Worksite smoking cessation programs offer accessibility of the target population, availability of occupational health support, and the potential for peer pressure and peer support. The purpose of this study was to identify the efficacy of the financial incentives given to various teams in the workplace. St. Paul's Hospital's employees were enrolled. Each team of employees consisted of smoking participants and non-smoking fellow workers from the same department. The financial incentive of 50000 won (about $45) was rewarded to the team for each successful participant-not to individual members-after the first week and then after one month. If the smokers in the team remained abstinent for a longer time period, the team was given an incentive of 100000 won for each successful participant after 3 and 6 months. A total 28 smoking participants and 6 teams were enrolled. Self-reported abstinence rates validated by urinary cotinine test at 3, 6, and 12 months after the initial cessation were 61%, 54%, and 50%, respectively. Smokers with high nicotine dependence scores or those who began participation 1 month after enrollment initiation had a lower abstinence rate at 3 months, but not at 6 and 12 months. Participants who succeeded at smoking cessation at 12 months were more likely to be older and have a longer smoking duration history. The financial incentives given to teams could be promising and effective to improve long-term rates of smoking cessation. This approach could use peer pressure and peer support in the workplace over a longer period.


Assuntos
Promoção da Saúde/economia , Motivação , Avaliação de Programas e Projetos de Saúde/métodos , Abandono do Hábito de Fumar/economia , Local de Trabalho , Adulto , Demografia , Feminino , Humanos , Masculino , Resultado do Tratamento
6.
Immune Netw ; 13(5): 213-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24198747

RESUMO

Enterotoxigenic Bacteroides fragilis (ETBF) is a human gut commensal bacteria that causes inflammatory diarrhea and colitis. ETBF also promotes colorectal tumorigenesis in the Min mouse model. The key virulence factor is a secreted metalloprotease called B. fragilis toxin (BFT). BFT induces E-cadherin cleavage, cell rounding, activation of the ß-catenin pathway and secretion of IL-8 in colonic epithelial cells. However, the precise mechanism by which these processes occur and how these processes are interrelated is still unclear. E-cadherin form homophilic interactions which tethers adjacent cells. Loss of E-cadherin results in detachment of adjacent cells. Prior studies have suggested that BFT induces IL-8 expression by inducing E-cadherin cleavage; cells that do not express E-cadherin do not secrete IL-8 in response to BFT. In the current study, we found that HT29/C1cells treated with dilute trypsin solution induced E-cadherin degradation and IL-8 secretion, consistent with the hypothesis that E-cadherin cleavage causes IL-8 secretion. However, physical damage to the cell monolayer did not induce IL-8 secretion. We also show that EDTA-mediated disruption of E-cadherin interactions without E-cadherin degradation was sufficient to induce IL-8 secretion. Finally, we determined that HT29/C1 cells treated with LiCl (ß-catenin activator) induced IL-8 secretion in a dose-dependent and time-dependent manner. Taken together, our results suggest that BFT induced IL-8 secretion may occur by the following process: E-cadherin cleavage, disruption of cellular interactions, activation of the ß-catenin pathway and IL-8 expression. However, we further propose that E-cadherin cleavage per se may not be required for BFT induced IL-8 secretion.

7.
Tuberc Respir Dis (Seoul) ; 72(6): 486-92, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23101015

RESUMO

BACKGROUND: The aim of this study was to analyze clinical situations requiring rigid bronchoscopy and evaluate usefulness of rigid bronchoscopic intervention in benign or malignant airway disorders. METHODS: We retrospectively reviewed 29 patients who underwent rigid bronchoscopy from November 2007 to February 2011 at St. Paul's Hospital, The Catholic University of Korea School of Medicine. RESULTS: Of the 29 patients, the most frequent underlying etiology was benign stenosis of trachea (n=20). Of those 20 patients, 16 had post-intubation tracheal stenosis (PITS), 2 had tracheal stenosis due to inhalation burn (IBTS) and other 2 had obstructive fibrinous tracheal pseudomembrane (OFTP). Other etiologies were airway malignancy (n=6), endobronchial stenosis due to tuberculosis (n=2), and foreign body (n=1). For treatment, silicone stent insertion was done in 16 cases of PITS and IBTS and mechanical removal was performed in 2 cases of OFTP. In 6 cases of malignant airway obstruction mechanical debulking was performed and silicone stents were inserted additionally in 2 cases. Balloon dilatation and electrocautery were used in 2 cases of endobronchial stenosis due to tuberculosis. In all cases of stent, airway obstructive symptom improved immediately. Granulation tissue formation was the most common complication. CONCLUSION: Tracheal stenosis was most common indication and silicone stenting was most common procedure of rigid bronchoscopy in our center. Rigid bronchoscopic procedures, at least tracheal silicone stenting, should be included in pulmonary medicine fellowship programs because it is a very effective and indispensable method to relieve critical airway obstruction which needs training to learn.

8.
J Korean Med Sci ; 25(9): 1384-6, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20808687

RESUMO

Obstructive fibrinous tracheal pseudomembrane is a rare, but potentially fatal complication associated with endotracheal intubation. It has been known that the formation of tracheal pseudomembrane is related with intracuff pressure during endotracheal intubation or infectious cause. But in the patient described in this case, pseudomembrane formation in the trachea was associated with subglottic epithelial trauma or caustic injuries to the trachea caused by aspirated gastric contents during intubation rather than tracheal ischemia due to high cuff pressure. We report a patient with obstructive fibrinous tracheal pseudomembrane after endotracheal intubation who presented with dyspnea and stridor and was treated successfully with mechanical removal using rigid bronchoscopy.


Assuntos
Obstrução das Vias Respiratórias/etiologia , Intubação Intratraqueal/efeitos adversos , Doenças da Traqueia/diagnóstico , Idoso , Obstrução das Vias Respiratórias/cirurgia , Broncoscopia , Feminino , Humanos , Tomografia Computadorizada por Raios X , Doenças da Traqueia/etiologia , Doenças da Traqueia/cirurgia
9.
Bioorg Med Chem ; 16(1): 530-5, 2008 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17936631

RESUMO

A series of coumarin types MMP inhibitors were designed based on gelastatin hydroxamates (1) and evaluated for TACE, cellular TNF-alpha, and NO inhibitory activities. Among them, compounds 9b had potent inhibitory activities in enzymatic and cellular assays and good selectivity to MMP-2 and MMP-9. Further investigation of 9b will be carried out for its efficacy in RA animal model system.


Assuntos
Cumarínicos , Metaloendopeptidases/antagonistas & inibidores , Inibidores de Proteases/síntese química , Proteínas ADAM/antagonistas & inibidores , Proteína ADAM17 , Ácidos Hidroxâmicos , Inibidores de Metaloproteinases de Matriz , Óxido Nítrico/antagonistas & inibidores , Inibidores de Proteases/farmacologia , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/antagonistas & inibidores
10.
Bioorg Med Chem Lett ; 17(22): 6234-8, 2007 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-17904843

RESUMO

Novel delta-lactam-based HDAC inhibitors which have various substituted benzyl, bi-aromatic cap groups were prepared using ring closure metathesis reaction, and evaluated their HDAC inhibitory activities and anti-proliferative effects. Among prepared analogues, 11m and 11o have very strong HDAC enzymatic inhibition and showed the most potent growth inhibitory activity to five human tumor cell lines including PC-3, ACHN, NUGC-3, HCT-15, and MBA-MB-231 tumor cell lines. Compounds 11m and 11o also showed good tumor growth inhibition of MDA-MB-231 cells in in vivo xenograft model. Structure-activity relationship study using docking model explained the significance of hydrophobic aromatic cap groups for their in vitro activities.


Assuntos
Inibidores de Histona Desacetilases , Lactamas/química , Lactamas/farmacologia , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Histona Desacetilases/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Korean J Intern Med ; 19(4): 261-5, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15683116

RESUMO

Pseudomembranous colitis is known to develop with long-term antibiotic administration, but antitubercular agents are rarely reported as a cause of this disease. We experienced a case of pseudomembranous colitis associated with rifampin. The patient was twice admitted to our hospital for the management of frequent bloody, mucoid, jelly-like diarrhea and lower abdominal pain that developed after antituberculosis therapy that included rifampin. Sigmoidoscopic appearance of the rectum and sigmoid colon and mucosal biopsy were compatible with pseudomembranous colitis. The antitubercular agents were discontinued and metronidazole was administered orally. The patient's symptoms were resolved within several days. The antituberculosis therapy was changed to isoniazid, ethambutol and pyrazinamide after a second bout of colitis. The patient had no further recurrence of diarrhea and abdominal pain. We report here on a case of pseudomembranous colitis associated with rifampin.


Assuntos
Antibióticos Antituberculose/efeitos adversos , Enterocolite Pseudomembranosa/induzido quimicamente , Rifampina/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Diarreia/etiologia , Humanos , Masculino , Tuberculose Pulmonar/tratamento farmacológico
12.
Cancer Res Treat ; 36(1): 68-71, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20396568

RESUMO

PURPOSE: The purpose of this study was to evaluate the efficacy of intrapleural chemotherapy (IPC) with cisplatin and cytarabine in the management of malignant pleural effusion (MPE) from non-small-cell lung cancer (NSCLC). MATERIALS AND METHODS: A prospective analysis was carried out on 40 patients with pathologically proven MPE from NSCLC who had received IPC. A single dose of cisplatin 100 mg/m(2) plus cytarabine 1200 mg/m(2) in 250 ml normal saline was instilled into the pleural space via a chest tube and drained 4 hours later. Patients were evaluated for toxicities and responses at 1, 2, & 3 weeks and then at monthly intervals if possible. Systemic chemotherapy was administered, if the patient agreed to receive it, after achieving complete control (CC) of MPE. RESULTS: The median duration of chest tube insertion for drainage was 7 (3 approximately 32) days. Among the assessable 37 patients, CC and partial control (PC) were 32 (86.5%) and 4 (10.8%) patients, respectively (overall response rate 97.3%). The median duration of response was 12 months (2 approximately 23) and there were only two relapses of IPC after achieving CC. Among the 35 patients who were assessable until they died, 28 patients (80.0%) maintained CC until the last follow-up. There was only one toxic death and the toxicities of IPC, versus the results obtained, were deemed acceptable. CONCLUSION: The procedures were tolerable to the patients and chemotherapy-induced complications were at an acceptable level. The outcome of this trial indicates that IPC has a superior and long lasting treatment response in the management of patients with MPE from NSCLC.

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