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1.
J Appl Microbiol ; 129(2): 411-421, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32086853

RESUMO

AIMS: Mitochondrial fission is an essential dynamics that maintains mitochondrial morphology and function. This study seeks to determine the roles of mitochondrial fission in the filamentous entomopathogenic fungus Beauveria bassiana. MATERIAL AND METHODS: Three fission-related genes (BbFis1, BbMdv1 and BbDnm1) were functionally characterized via protein intracellular localization and construction of gene disruption mutants. RESULTS: Mitochondrial localization was only observed for BbFis1 which interacts with BbMdv1, but BbMdv1 did not have interaction with BbDnm1. Single disruption mutant of three genes generated the elongated and enlarged mitochondria which could not be eliminated via the mitophagy. Three mutant strains displayed the reduced ATP synthesis and vegetative growth compared with the wild type. Three genes were involved in the early stage of conidiation and unnecessary for the late stage. However, all three genes significantly contribute to blastospore development under submerged condition, and the loss of BbMdv1 had the greatest effects compared with the losses of BbFis1 or BbDnm1. Finally, disruption of three genes significantly attenuated fungal virulence, but their mutations had different influences. CONCLUSIONS: In addition to their consistent roles in mitochondrial division and mitophagy, three fission-related genes perform divergent roles in the development and virulence of the entomopathogenic fungus B. bassiana. SIGNIFICANCE AND IMPACT OF THE STUDY: This study shows that mitochondrial fission is associated with lifecycle of B. bassiana. These findings provide information for the manipulation of fungal physiology and facilitate the application of entomopathogenic fungi.


Assuntos
Beauveria/crescimento & desenvolvimento , Beauveria/patogenicidade , Insetos/microbiologia , Dinâmica Mitocondrial/fisiologia , Mitofagia , Animais , Beauveria/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Dinâmica Mitocondrial/genética , Mitofagia/genética , Esporos Fúngicos/crescimento & desenvolvimento , Virulência/genética
2.
J Appl Microbiol ; 112(1): 175-84, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22044666

RESUMO

AIMS: Probing possible mechanisms involved in the resistance of entomopathogenic fungus Isaria fumosorosea to carbendazim fungicide. METHODS AND RESULTS: A carbendazim-sensitive strain (If116) selected from 15 wild-type strains was subjected to NaNO(2) -induced mutagenesis, yielding nine mutants with carbendazim resistance increased by 82- to 830-fold and thermotolerance decreased by 15-51%. Comparing the protein sequences deduced from the α- and ß-tubulin genes of If116 and its mutants revealed no traceable site mutation relating to the enhanced resistance although the transcripts levels of ß-tubulin gene in all mutants were 0·87- to 7·16-fold of that in If116. Three examined mutants showed multidrug resistance because they were significantly more resistant to glufosinate, imidacloprid and other six fungicides than If116 during growth. Further examination of rhodamine-stained blastospores revealed existence of drug efflux pump protein(s) in all carbendazim-resistant mutants. Thus, the sequences of an ATP-binding cassette (ABC) transporter gene (ifT1) and its promoter region cloned from the wild-type and mutant strains were analysed. Three common point mutations were located, respectively, at the binding sites of Gal4, Abf1 and Raf, which are crucial transcription factors in the regulative network of numerous protein loci. Such point mutations elevated the ifT1 expression by 17 to 137-fold in all the mutants. CONCLUSIONS: The overexpression of the ABC transporter caused by the point mutations at the binding sites was responsible for the fungal resistance to various pesticides including carbendazim. SIGNIFICANCE AND IMPACT OF STUDY: The transporter-mediated multidrug resistance found for the first time in entomopathogenic fungi is potential for use in improving mycoinsecticide compatibility with chemical pesticides.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Benzimidazóis/farmacologia , Carbamatos/farmacologia , Saccharomycetales , Tubulina (Proteína)/genética , Transportadores de Cassetes de Ligação de ATP/química , Resistência a Medicamentos/genética , Fungicidas Industriais/farmacologia , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Temperatura Alta , Dados de Sequência Molecular , Mutação/genética , Saccharomycetales/efeitos dos fármacos , Saccharomycetales/genética , Saccharomycetales/metabolismo
3.
Clin Transl Oncol ; 21(2): 167-177, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30003530

RESUMO

PURPOSE: To assess the efficacy and safety of drug-eluting beads transarterial chemoembolization (DEB-TACE) in liver cancer patients with different times of previous conventional transarterial chemoembolization (cTACE) treatments. METHODS: 367 liver cancer patients about to receive DEB-TACE treatment were enrolled in this prospective cohort study. All patients were divided into no previous cTACE group (NPC group), 1-2 times previous cTACE group (PC group) and triple or above previous cTACE group (TPC group) according to the times of previous cTACE treatments. RESULTS: There was no difference in complete response (CR) (P = 0.671) and objective response rate (ORR) (P = 0.062) among three groups. Additionally, no difference in overall survival (OS) among groups (P = 0.899) was found. As to liver function, most liver function indexes were deteriorative at 1 week after DEB-TACE operation, but returned to baseline at 1-3 months after DEB-TACE operation in all three groups, while percentage of abnormal total bile acid (TBA) patients was higher in TPC group than NPC and PC groups at 1-3 month post-DEB-TACE (P = 0.018). As for safety profiles, the incidence of pain during DEB-TACE operation was lower in TPC group compared to NPC and PC groups (P = 0.005), while no difference of other adverse events was found during and 1 month post-DEB-TACE treatment among three groups. CONCLUSION: DEB-TACE treatment was equally efficient and tolerated in liver cancer patients with different times of previous cTACE treatments.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Quimioembolização Terapêutica/métodos , Doxorrubicina/administração & dosagem , Neoplasias Hepáticas/terapia , Adulto , Idoso , Quimioembolização Terapêutica/mortalidade , Portadores de Fármacos , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Masculino , Microesferas , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/terapia , Resultado do Tratamento
4.
Ann N Y Acad Sci ; 1039: 430-5, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15826995

RESUMO

Two hereditary ataxia syndromes show distinct profiles of region-specific atrophy and ocular motor deficits. Selective pontine atrophy is associated with slowed saccades in ataxin-2 mutations, and selective floccular atrophy is associated with impaired pursuit and gaze-holding abnormalities in Ca(V)2.1 mutations. Although the flocculus seems to be spared relative to the pons in ataxin-2 mutations, and pursuit and gaze-holding appear to be relatively normal, these can be difficult to assess at the bedside, as corrective saccades are also slow and hard to discern. Here, we show the presence of significant floccular atrophy compared with controls in both ataxin-2 and Ca(V)2.1 mutations, which raises the possibility that abnormalities of smooth pursuit or gaze-holding are present in both conditions.


Assuntos
Canais de Cálcio/genética , Mutação , Proteínas do Tecido Nervoso/genética , Ataxias Espinocerebelares/genética , Adulto , Idoso , Ataxinas , Atrofia , Canais de Cálcio/fisiologia , Movimentos Oculares , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/fisiologia , Ataxias Espinocerebelares/patologia , Ataxias Espinocerebelares/fisiopatologia
5.
Drug Res (Stuttg) ; 65(2): 101-6, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25076224

RESUMO

The objective of the present study was to examine the antitumor efficacy of the ethanol extract from Artemisia dracunculus as well as the compounds isolated from it on cultured EC­109 esophageal squamous cell carcinoma (ESCC) cells. Apoptotic activities of the compounds were also studied using flow cytometry. EC­109 esophageal cancer cells were treated with varying concentrations of compounds 1-7 isolated from the plant as well as the ethanol extract of Artemisia dracunculus. The cytotoxicity was evaluated by MTT assay and the apoptotic studies of the compounds were determined using flow-cytometry. Effect on mitochondrial membrane potential loss ΛΨ m induced by compounds 2 and 4 was also studied in these cells. Bioassay-guided fractionation of the ethanol extract from the shoot and root parts of Artemisia dracunculus led to the isolation of 7-methoxycoumarin (1), scopoletin (2), dracumerin (3), sakuranetin (4), elimicin (5), davidigenin (6) and 6-methoxycapillarisin (7). All the compounds as well as the extract showed mild to potent cell proliferation inhibitory activities against the esophageal cell line. Sakuranetin and 6-methoxycapillarisin were found to have the most potent effects in inhibiting the cell proliferation. The 2 potent compounds, sakuranetin and 6-methoxycapillarisin were evaluated for their effects on cell cycle phase distribution (DNA damage) as well as their effects on mitochondrial membrane potential loss ΛΨ m. Both compounds induced DNA damage as well as mitochondrial membrane potential loss in esophageal cancer cells. The study suggests that compounds, Sakuranetin and 6-methoxycapillarisin isolated from Artemisia dracunculus possess potent anticancer effects by inducing DNA damage in these cells.


Assuntos
Apoptose/efeitos dos fármacos , Artemisia/química , Carcinoma de Células Escamosas/tratamento farmacológico , Cromonas/uso terapêutico , Neoplasias Esofágicas/tratamento farmacológico , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cromonas/isolamento & purificação , Cromonas/farmacologia , Dano ao DNA/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago , Etanol , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Extratos Vegetais/farmacologia , Raízes de Plantas/química
6.
AJNR Am J Neuroradiol ; 36(8): 1400-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25907519

RESUMO

BACKGROUND AND PURPOSE: We sought to compare the accuracy of a volumetric fully automated computer assessment of hippocampal volume asymmetry versus neuroradiologists' interpretations of the temporal lobes for mesial temporal sclerosis. Detecting mesial temporal sclerosis (MTS) is important for the evaluation of patients with temporal lobe epilepsy as it often guides surgical intervention. One feature of MTS is hippocampal volume loss. MATERIALS AND METHODS: Electronic medical record and researcher reports of scans of patients with proved mesial temporal sclerosis were compared with volumetric assessment with an FDA-approved software package, NeuroQuant, for detection of mesial temporal sclerosis in 63 patients. The degree of volumetric asymmetry was analyzed to determine the neuroradiologists' threshold for detecting right-left asymmetry in temporal lobe volumes. RESULTS: Thirty-six patients had left-lateralized MTS, 25 had right-lateralized MTS, and 2 had bilateral MTS. The estimated accuracy of the neuroradiologist was 72.6% with a κ statistic of 0.512 (95% CI, 0.315-0.710) [moderate agreement, P < 3 × 10(-6)]), whereas the estimated accuracy of NeuroQuant was 79.4% with a κ statistic of 0.588 (95% CI, 0.388-0.787) [moderate agreement, P < 2 × 10(-6)]). This discrepancy in accuracy was not statistically significant. When at least a 5%-10% volume discrepancy between temporal lobes was present, the neuroradiologists detected it 75%-80% of the time. CONCLUSIONS: As a stand-alone fully automated software program that can process temporal lobe volume in 5-10 minutes, NeuroQuant compares favorably with trained neuroradiologists in predicting the side of mesial temporal sclerosis. Neuroradiologists can often detect even small temporal lobe volumetric changes visually.


Assuntos
Epilepsia do Lobo Temporal/diagnóstico , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Lobo Temporal/patologia , Adulto , Epilepsia do Lobo Temporal/patologia , Feminino , Hipocampo/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Estudos Retrospectivos , Esclerose/patologia , Software
7.
AJNR Am J Neuroradiol ; 36(1): 84-90, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25169926

RESUMO

BACKGROUND AND PURPOSE: Site-specific degeneration patterns of the infratentorial brain in relation to phylogenetic origins may relate to symptoms in patients with spinocerebellar degeneration, but the patterns are still unclear. We investigated macro- and microstructural changes of the infratentorial brain based on phylogenetic origins and their correlation with symptoms in patients with spinocerebellar ataxia type 6. MATERIALS AND METHODS: MR images of 9 patients with spinocerebellar ataxia type 6 and 9 age- and sex-matched controls were obtained. We divided the infratentorial brain on the basis of phylogenetic origins and performed an atlas-based analysis. Comparisons of the 2 groups and a correlation analysis assessed with the International Cooperative Ataxia Rating Scale excluding age effects were performed. RESULTS: A significant decrease of fractional volume and an increase of mean diffusivity were seen in all subdivisions of the cerebellum and in all the cerebellar peduncles except mean diffusivity in the inferior cerebellar peduncle in patients compared with controls (P < .0001 to <.05). The bilateral anterior lobes showed the strongest atrophy. Fractional volume decreased mainly in old regions, whereas mean diffusivity increased mainly in new regions of the cerebellum. Reflecting this tendency, the International Cooperative Ataxia Rating Scale total score showed strong correlations in fractional volume in the right flocculonodular lobe and the bilateral deep structures and in mean diffusivity in the bilateral posterior lobes (r = 0.73 to ±0.87). CONCLUSIONS: We found characteristic macro- and microstructural changes, depending on phylogenetic regions of the infratentorial brain, that strongly correlated with clinical symptoms in patients with spinocerebellar ataxia type 6.


Assuntos
Tronco Encefálico/patologia , Cerebelo/patologia , Ataxias Espinocerebelares/patologia , Adulto , Idoso , Atrofia/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Filogenia , Índice de Gravidade de Doença
11.
AJNR Am J Neuroradiol ; 29(3): 550-1, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18184833

RESUMO

SUMMARY: A 50-year-old woman presented with intermittent headache for the past few years. A paranasal sinus CT scan showed a diffusely calcified lesion at the roof of the sphenoid sinus and sella turcica, with the sellar floor bony cortex involved. Empty sella was noted. MR imaging revealed a soft-tissue lesion with low signal intensity on T1-weighted images, high signal intensity on T2-weighted images, and heterogeneous enhancement on postgadolinium images. Histologic examination revealed an osteoma composed of mature lamellar bone.


Assuntos
Imageamento por Ressonância Magnética , Osteoma/diagnóstico , Neoplasias dos Seios Paranasais/diagnóstico , Sela Túrcica/diagnóstico por imagem , Sela Túrcica/patologia , Seio Esfenoidal/diagnóstico por imagem , Seio Esfenoidal/patologia , Tomografia Computadorizada por Raios X , Feminino , Humanos , Pessoa de Meia-Idade
12.
Lett Appl Microbiol ; 43(3): 331-5, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16910941

RESUMO

AIMS: To produce more thermotolerable conidia of Beauveria bassiana, a well-known fungal biocontrol agent, by optimizing the medium components and culture conditions. METHODS AND RESULTS: The conidia produced on media including 0.5-6% glucose, sucrose or starch as carbon source and 50-300-microg ml(-1) Cu2+, Zn2+, Mn2+ or Fe3+ as additive to Sabouraud dextrose medium at 15-30 degrees C, pH 4-8 or KCl-adjusted water availabilities were exposed to 30-min wet heat stress at 48 degrees C. The medium components for conidial production with greatly enhanced thermotolerance included 4% glucose as optimum or 1% starch as alternative for the carbon source and < or =50-microg ml(-1) Mn2+ for the metal additive. The culture conditions were optimized as 25 degrees C and pH 5-6. Conidial thermotolerance decreased remarkably when sucrose and Fe3+ or Cu2+ were used in the cultures, but altered slightly when 50-200-microg ml(-1) Zn2+ were included. CONCLUSIONS: The tolerance of B. bassiana conidia to the thermal stress was significantly affected by the medium composition and culture conditions under which the conidia were produced. SIGNIFICANCE AND IMPACT OF THE STUDY: Proper treatment of small grains as mass production substrates for more glucose release and supplement of glucose or 50-microg ml(-1) Mn2+ are possible means to enhancing conidial thermotolerance and field persistence for improved insect control.


Assuntos
Meios de Cultura/química , Meios de Cultura/farmacologia , Resposta ao Choque Térmico/efeitos dos fármacos , Hypocreales/efeitos dos fármacos , Hypocreales/fisiologia , Carboidratos/análise , Carboidratos/farmacologia , Carbono/análise , Carbono/farmacologia , Temperatura Alta , Concentração de Íons de Hidrogênio , Hypocreales/crescimento & desenvolvimento , Metais/análise , Metais/farmacologia , Água
13.
Exp Brain Res ; 171(3): 297-305, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16307245

RESUMO

We recorded divergence eye movements after short (4 s) and long (36 s) periods of sustained symmetrical convergence (30 degrees) in nine normal human subjects using the search coil technique. Following the long period of convergence, alignment after the initial 1,250 ms of divergence was more converged than after the short period of convergence, showing short-term "phoria adaptation". The first 1,000 ms of divergence, however, could be slower, faster or relatively unchanged, depending upon the subject. A change in the timing and/or amplitude of associated saccades (which accelerate ongoing vergence) between the long and short stimuli accounted for much of the difference in the rate of divergence. The differences in saccade pattern during early divergence following the long and short periods of convergence may reflect changes in attentional focus (to near or to far).


Assuntos
Adaptação Fisiológica/fisiologia , Convergência Ocular/fisiologia , Movimentos Sacádicos/fisiologia , Estrabismo/fisiopatologia , Adulto , Atenção/fisiologia , Sinais (Psicologia) , Interpretação Estatística de Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa
14.
Biotechnol Lett ; 28(11): 799-804, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16786244

RESUMO

A novel solid-state fermentation apparatus, namely an upright multi-tray conidiation chamber, was developed to facilitate the production of aerial conidia of fungal biocontrol agents, such as Beauveria bassiana. The chamber with 25 bottom-meshed metal trays had a capacity of > or =50 kg rice with each tray holding > or =2 kg. In repeated trials, a mean yield of 2.4 (1.8-2.7) x 10(12) conidia kg(-1) rice was harvested from the 7-day cultures of B. bassiana in a fully loaded chamber. The new apparatus has a high potential for bulk production of fungal conidia.


Assuntos
Beauveria/isolamento & purificação , Fermentação , Controle Biológico de Vetores/métodos , Esporos Fúngicos/isolamento & purificação , Equipamentos e Provisões , Incubadoras/microbiologia , Micologia/instrumentação , Oryza/microbiologia , Esporos Fúngicos/crescimento & desenvolvimento
15.
Neurology ; 66(3): 424-6, 2006 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-16476946

RESUMO

Spinocerebellar ataxia type 2 (SCA2) has protean manifestations, and a clinical marker of progression is needed. Although MRI is a promising tool, it is unclear whether the degree of atrophy shown on MRI is correlated with clinical dysfunction. Here the authors used high-resolution volumetric MRI analysis to show that cerebellar and pontine volumes specifically and closely correlate with functional staging scores.


Assuntos
Cerebelo/patologia , Imageamento por Ressonância Magnética , Ponte/patologia , Ataxias Espinocerebelares/diagnóstico , Ataxias Espinocerebelares/fisiopatologia , Adulto , Idoso , Atrofia , Estudos de Casos e Controles , Avaliação da Deficiência , Feminino , Humanos , Pessoa de Meia-Idade
16.
J Appl Microbiol ; 97(2): 323-31, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15239698

RESUMO

AIMS: This study was to illustrate the relationship between the thermotolerance and the contents of hydrophobin-like or formic-acid-extractable (FAE) proteins in aerial conidia of Beauveria bassiana and Paecilomyces fumosoroseus produced on rice-based substrate. METHODS AND RESULTS: Survival indices of 11 isolates were separately assessed as a ratio of the viability of conidia after 3-150 min thermal stress at 48 degrees C over that of unstressed conidia and fitted well to a survival model (r(2) >/= 0.97). For a given isolate, the fitted model generated an LT(50), the time for 50% viability loss under the stress. The LT(50)s of six B. bassiana isolates (10.1-61.9 min) and five P. fumosoroseus isolates (2.8-6.2 min) were correlated (r(2) = 0.81) with FAE protein contents (6.9-23.4 microg mg(-1)). The survival indices of a fixed B. bassiana isolate after 45-min thermal stress at 48 degrees C were also correlated to the FAE protein contents from conidia produced on glucose-, sucrose-, or starch-based substrate (0.79

Assuntos
Proteínas Fúngicas/fisiologia , Temperatura Alta , Hypocreales/fisiologia , Paecilomyces/fisiologia , Controle Biológico de Vetores , Contagem de Colônia Microbiana , Eletroforese em Gel de Poliacrilamida , Formiatos/metabolismo , Glucose/metabolismo , Hypocreales/crescimento & desenvolvimento , Paecilomyces/crescimento & desenvolvimento , Amido/metabolismo , Sacarose/metabolismo
17.
Conf Proc IEEE Eng Med Biol Soc ; 2004: 5050-2, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-17271452

RESUMO

Radiographic examination and palpation have been two of most common the methods often used in clinical assessment for implant stability for years. However, radiographs are two-dimensional and difficult to standardize in dental clinical diagnosis. In current study, an in vitro model for dental implant during osseointegration was designed and tested. To attain optimal healing range prior to frequency measurement, removal torque measurements of the initial as well as plateau mechanical bounding force will be exam for various stiffness of the base materials. Resonance frequency measurements will then be taken at predetermined healing intervals on implants placed in experimental animal. Significance between mechanical stability and increase in resonance frequency will be observed in search of its correlation with the stability of the implant-tissue interface.

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