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1.
J Biosci Bioeng ; 135(3): 232-237, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36693775

RESUMEN

The microparticle-enhanced cultivation (MPEC) was used to enhance the production of Antrodin C by submerged fermentation of medicinal mushroom Antrodia cinnamomea. The crucial factors such as types, sizes, concentrations, and addition time of microparticles were optimized. The mechanism of MPEC on the membrane permeability and fluidity of A. cinnamomea and the expression of key genes in Antrodin C were investigated. When talc (18 µm, 2 g/L) was added into the fermentation liquid at 0 h, the promoting effect on Antrodin C was the best. The maximum yield of Antrodin C was 1615.7 mg/L, which was about 2.98 times of the control (541.7 mg/L). Talc slightly damaged the mycelia of A. cinnamomea, increased the release of intracellular constituents, and enhanced the index of unsaturated fatty acid. In addition, the key genes (IDI, E2.3.3.10, HMGCR, atoB) that might play an important role in the synthesis of the triquine-type sesquiterpene Antrodin C, were upregulated. In conclusion, talc increased the permeability and fluidity of cell membrane, upregulated the key genes and improved the biosynthesis process to enhance the yield of Antrodin C in the submerged fermentation of A. cinnamomea.


Asunto(s)
Agaricales , Antrodia , Talco/metabolismo , Antrodia/genética , Antrodia/metabolismo
2.
Int J Mol Sci ; 23(10)2022 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-35628368

RESUMEN

Xanthomonas oryzae pv. oryzae (Xoo) strains that cause bacterial leaf blight (BLB) limit rice (Oryza sativa) production and require breeding more resistant varieties. Transcription activator-like effectors (TALEs) activate transcription to promote leaf colonization by binding to specific plant host DNA sequences termed effector binding elements (EBEs). Xoo major TALEs universally target susceptibility genes of the SWEET transporter family. TALE-unresponsive alleles of clade III OsSWEET susceptibility gene promoter created with genome editing confer broad resistance on Asian Xoo strains. African Xoo strains rely primarily on the major TALE TalC, which targets OsSWEET14. Although the virulence of a talC mutant strain is severely impaired, abrogating OsSWEET14 induction with genome editing does not confer equivalent resistance on African Xoo. To address this contradiction, we postulated the existence of a TalC target susceptibility gene redundant with OsSWEET14. Bioinformatics analysis identified a rice locus named ATAC composed of the INCREASED LEAF INCLINATION 2 (ILI2) gene and a putative lncRNA that are shown to be bidirectionally upregulated in a TalC-dependent fashion. Gain-of-function approaches with designer TALEs inducing ATAC sequences did not complement the virulence of a Xoo strain defective for SWEET gene activation. While editing the TalC EBE at the ATAC loci compromised TalC-mediated induction, multiplex edited lines with mutations at the OsSWEET14 and ATAC loci remained essentially susceptible to African Xoo strains. Overall, this work indicates that ATAC is a probable TalC off-target locus but nonetheless documents the first example of divergent transcription activation by a native TALE during infection.


Asunto(s)
Oryza , Efectores Tipo Activadores de la Transcripción , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Resistencia a la Enfermedad/genética , Susceptibilidad a Enfermedades , Regulación de la Expresión Génica de las Plantas , Oryza/metabolismo , Fitomejoramiento , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Talco/metabolismo , Efectores Tipo Activadores de la Transcripción/metabolismo , Xanthomonas
3.
Appl Biochem Biotechnol ; 194(10): 4333-4347, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35083705

RESUMEN

Liquid submerged fermentation is an effective strategy to achieve large-scale production of active ingredients by macrofungi, and controlling mycelium morphology is a key factor restricting the development of this technology. Mining for superior morphological regulatory factors and elucidation of their regulatory mechanisms are vital for the further development of macrofungal fermentation technology. In this study, microparticles were used to control the morphology of Paraisaria dubia (P. dubia) in submerged fermentation, and the underlying regulatory mechanisms were revealed by transcriptomic. The relative frequency of S-type pellet diameter increased significantly from 7.14 to 88.31%, and biomass increased 1.54 times when 15 g/L talc was added. Transcriptome analysis showed that the morphological regulation of filamentous fungi was a complex biological process, which involved signal transduction, mycelium polar growth, cell wall synthesis and cell division, etc. It also showed a positive impact on the basic and secondary metabolism of P. dubia. We provided a theoretical basis for controlling the mycelium morphology of P. dubia in submerged fermentation, which will promote the development of macrofungal fermentation technology.


Asunto(s)
Hypocreales , Talco , Fermentación , Perfilación de la Expresión Génica , Micelio , Talco/metabolismo , Transcriptoma
4.
World J Microbiol Biotechnol ; 32(12): 205, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27804104

RESUMEN

Postbloom fruit drop (PFD) caused by Colletotrichum acutatum affects flowers and causes early fruit drop in all commercial varieties of citrus. Biological control with the isolate ACB-69 of Bacillus subtilis has been considered as a potential method for controlling this disease. This study aimed to develop and optimize a B. subtilis based-formulation with a potential for large-scale applications and evaluate its effect on C. acutatum in vitro and in vivo. Bacillus subtilis based-formulations were developed using different carrier materials, and their ability to control PFD was evaluated. The results of the assays led to the selection of the B. subtilis based-formulation with talc + urea (0.02 %) and talc + ammonium molybdate (1 mM), which inhibited mycelial growth and germination of C. acutatum. Studies with detached citrus flowers showed that the formulations were effective in controlling the pathogen. In field conditions, talc + urea (0.02 %) provided 73 % asymptomatic citrus flowers and 56 % of the average number of effective fruit (ANEF), equating with fungicide treatment. On the contrary, non-treated trees had 8.8 % of asymptomatic citrus flowers and 0.83 % ANEF. The results suggest that B. subtilis based-formulations with talc as the carrier supplemented with a nitrogen source had a high potential for PFD control.


Asunto(s)
Bacillus subtilis/fisiología , Citrus/crecimiento & desarrollo , Colletotrichum/efectos de los fármacos , Fungicidas Industriales/farmacología , Enfermedades de las Plantas/prevención & control , Citrus/microbiología , Colletotrichum/patogenicidad , Flores/crecimiento & desarrollo , Flores/microbiología , Fungicidas Industriales/metabolismo , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Molibdeno/metabolismo , Molibdeno/farmacología , Talco/metabolismo , Talco/farmacología , Urea/metabolismo , Urea/farmacología
5.
Cell Mol Biol (Noisy-le-grand) ; 60(5): 73-81, 2014 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-25535716

RESUMEN

Stress tolerating strain of Pseudomonas aeruginosa PF07 possessing plant growth promoting activity was screened for the production of exopolysaccharides (EPS). EPS production was monitored in the cell free culture supernatant (CFCS) and extracted EPS was further purified by thin layer chromatography. EPS producing cells were taken to design talc based formulation and its efficacy was checked on oilseed crop sunflower (Hellianthus annuus), under in vivo saline conditions (soil irrigated with 125 mM of saline water). Application of bioformulation significantly enhanced the yield and growth attributes of the plant in comparison to control (untreated seeds) under stress and non—stress conditions. Germination rate, plant length, dry weight and seed weight increased remarkably. The above findings suggest the application and benefits of utilizing EPS formulation in boosting early seedling emergence, enhancing plant growth parameters, increasing seed weight and mitigating stress in saline affected regions. Such bioformulation may enhance RAS/RT (Root Adhering Soil to Root Tissue ratio), texture of the soil, increase porosity, improve uptake of nutrients, and hence may be considered as commercially important formulation for renovation of stressed sites and enhancing plant growth.


Asunto(s)
Helianthus/crecimiento & desarrollo , Polisacáridos Bacterianos/metabolismo , Pseudomonas aeruginosa/metabolismo , Talco/metabolismo , Salinidad
6.
J BUON ; 14(3): 419-23, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19810132

RESUMEN

PURPOSE: Talc remains a commonly used agent for pleurodesis malignant pleural effusion. Nevertheless, it is associated with a 3-9% incidence of pulmonary reactions ranging from simple pneumonitis to acute respiratory distress syndrome (ARDS). The underlying lung pathology and the size and rate of talc particle dissemination have been implicated as the cause of these complications. There seems to be an acknowledged lack of evidence regarding detailed very early intrathoracic talc particle migration. MATERIALS AND METHODS: Thirty white male New Zealand rabbits underwent experimental pleurodesis and were randomly assigned to 3 (A, B, C) study groups (10 in each group). Rabbits were sacrificed 6, 12 and 18 h after talc administration. Samples from both lungs, mediastinum and parietal pleura were obtained. The number of talc crystals (m) deposited was counted and averaged along all slices of the various tissue samples. RESULTS: A high degree of early talc deposition and subsequent epithelial injury in all examined tissues was observed. Diffuse talc deposition occurred in both lungs, but in a different manner. On the side of talc administration, talc particles were deposited in a time-dependent fashion. On the contralateral side, talc was rapidly deposited during the first hours after the procedure, then the rate of deposition decreased, and increased again between 12 and 18 h after the procedure. CONCLUSION: Large-sized talc particles are deposited on both lungs very early after pleurodesis. At the same time inflammatory pulmonary changes appear bilaterally. Despite contradicting data in the literature, these findings should always be kept in mind when performing this procedure in high risk patients.


Asunto(s)
Pulmón/metabolismo , Pleura/metabolismo , Derrame Pleural Maligno/terapia , Pleurodesia , Neumonía/inducido químicamente , Talco/metabolismo , Animales , Modelos Animales de Enfermedad , Pulmón/efectos de los fármacos , Pulmón/patología , Masculino , Pleura/efectos de los fármacos , Pleura/patología , Neumonía/metabolismo , Neumonía/patología , Conejos , Talco/administración & dosificación , Talco/efectos adversos , Distribución Tisular
7.
Clin Nucl Med ; 28(10): 811-4, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14508271

RESUMEN

Talc pleurodesis is a technique used in the treatment of patients with persistent pleural effusions or pneumothorax not amenable to other treatment. These are commonly seen in patients with malignant thoracic neoplasms. Radiographic abnormalities resulting from prior talc pleurodesis could be confused with progression of the underlying neoplastic process. Positron emission tomography with F-18 fluorodeoxyglucose (FDG-PET) might be unable to distinguish between malignant and benign inflammatory processes. This report demonstrates the use of combined positron emission tomography/computed tomography (PET/CT) in a patient with a history of both malignant neoplasm and a prior talc pleurodesis. Fusion of PET and CT studies could add information that CT and PET alone cannot. This could alter the diagnostic and therapeutic course for patients with a history of both thoracic neoplasm and talc pleurodesis.


Asunto(s)
Quilotórax/diagnóstico por imagen , Quilotórax/terapia , Fluorodesoxiglucosa F18 , Pleurodesia , Técnica de Sustracción , Talco/metabolismo , Tomografía Computarizada de Emisión/métodos , Tomografía Computarizada por Rayos X/métodos , Quilotórax/metabolismo , Diagnóstico Diferencial , Errores Diagnósticos , Fluorodesoxiglucosa F18/farmacocinética , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pleurales/diagnóstico por imagen , Radiofármacos/farmacocinética
8.
Am J Gastroenterol ; 90(12): 2164-6, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8540508

RESUMEN

OBJECTIVES: The presence of talc crystals in the liver has been associated with prior history of i.v. drug abuse (IVDA). Patients with hepatitis C virus (HCV) infection often deny IVDA, and many patients have no other identifiable risk factors. To evaluate the role of prior surreptitous IVDA in patients with chronic HCV infection and to assess the role of talc identification in liver tissue, an epidemiological evaluation was performed. METHODS: One hundred and nine patients with chronic HCV (ALT abnormal > 6 months, HCV ELISA and recombinant immunoblot assay positive) underwent careful evaluation for risk factors potentially associated with HCV infection. All patients then had liver biopsy. Liver biopsies were reviewed by two observers to determine histological stage and were then examined by polarized light microscopy to reveal the presence or absence of typical talc crystals. Patients with discordance between history and histological findings were re-interviewed and were confronted with the information. RESULTS: Patient interviews revealed the following risk factors: IVDA, 17.1%; blood transfusion, 24.3%; possible household/occupational exposure, 14.4%; and tattoos, 15.3%. No identifiable risk factors were noted in 28.8% of the cohort. Talc crystals were seen in 9/109 (8.3%) of liver specimens. Of this group, only two patients admitted to prior history of IVDA. Seventeen patients with an IVDA history did not have identifiable talc crystals. Follow-up phone interviews were possible with five out of seven patients with liver talc who had previously denied IVDA history. Of the five patients, three admitted to prior IVDA but only after being confronted with the liver biopsy evidence. CONCLUSIONS: The findings of talc crystals in liver biopsy specimens appears to be a specific, but not a sensitive, marker for prior IVDA. Identification of talc crystals from liver tissue may contribute to categorization of risk factors in patients with community-acquired HCV infection. Tattoos are an important, and frequently unrecognized, risk factor for HCV infection. Despite these findings, a significant proportion of patients still have no identifiable risk factor for HCV acquisition.


Asunto(s)
Hepatitis C/metabolismo , Hepatitis Crónica/metabolismo , Hígado/metabolismo , Talco/metabolismo , Adulto , Anciano , Biopsia , Estudios de Cohortes , Femenino , Hepatitis Crónica/epidemiología , Humanos , Hígado/patología , Masculino , Microscopía de Polarización , Persona de Mediana Edad , Estudios Prospectivos , Abuso de Sustancias por Vía Intravenosa/metabolismo
9.
Gastroenterology ; 99(1): 51-60, 1990 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2160900

RESUMEN

Insulinlike growth factor I is a potent mitogen with insulinlike metabolic effects. Insulinlike growth factor I is synthesized in the liver, intestine, and other organs. Insulinlike growth factor I receptors are widely distributed and structurally similar to insulin receptors. Frozen sections of rabbit gastrointestinal tract were incubated in buffer containing 40 pmol/L [125I]insulinlike growth factor I. Binding was saturable, temperature- and time-dependent, and reversible. Saturation binding experiments showed a single class of high-affinity receptors (Kd = 0.9 nmol/L, Bmax = 0.36 pmol/mg protein). The IC50s for insulinlike growth factor I and insulinlike growth factor II were 3 nmol/L and 90 nmol/L, respectively; whereas insulin at 1-3 mumol/L displaced 50% of specific binding. Autoradiography of insulinlike growth factor I binding demonstrated significant differences in receptor density in gastrointestinal smooth muscle, epithelium of the esophagus, stomach, small intestine, and colon. These results indicate that a single class of specific, high-affinity insulinlike growth factor I receptors were distributed in muscular and mucosal layers of the entire rabbit gastrointestinal tract. Insulinlike growth factor I is likely to be an important local mediator of intestinal growth and metabolism.


Asunto(s)
Factor I del Crecimiento Similar a la Insulina/metabolismo , Mucosa Intestinal/ultraestructura , Receptores de Superficie Celular/ultraestructura , Somatomedinas/metabolismo , Animales , Autorradiografía , Cromatografía Líquida de Alta Presión , Técnicas de Cultivo , Músculo Liso/ultraestructura , Conejos , Receptores de Superficie Celular/efectos de los fármacos , Receptores de Superficie Celular/metabolismo , Receptores de Somatomedina , Talco/metabolismo
11.
Z Erkr Atmungsorgane ; 157(3): 238-46, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-7340208

RESUMEN

Neutron activation provides a sensitive technique to estimate pulmonary deposition, translocation and clearance of inhaled particles. Talc and fly ash were irradiated in an integrated neutron flux of or approximately 10(16) n/cm2. Radionuclides were induced by (n, gamma) reactions on major an minor elements in the dusts. Hamsters received a single nose-only exposure to the dusts. Groups of 4 to 6 animals were than serially sacrificed at intervals up to 4 months postexposure. Lungs, other tissues of interest and excreta were collected for gamma-ray analysis. Limit of detection for the isotopes 60Co or 46Sc was or approximately 0.1 dpm, facilitating detection of 10(-11) gram quantities of these elements. Analyzing for more than one radionuclide and comparing their ratios in the bulk dust to those in the tissue or excreta indicated whether a radionuclide leached from the particle or represented particles in the tissue samples. Six to 8% of the inhaled talc were deposited in the alveoli; its biological half-life in the lung was 7 to 10 days. Alveolar clearance was essentially complete 4 months postexposure. No translocation of talc to liver, kidneys, ovaries of other parts of the body was found. Picogram quantities of 60Co found in the urine probably represented leached 60Co, absorbed in the gastrointestinal tract. Two to 3% of the inhaled fly ash were initially retained in the respiratory tract. Estimated biological half-lives were 3 and 35 days for airways and alveoli, respectively. After 99 days the mean lung burden had decreased to about 10% of its initial value; extrapolation suggests near-complete pulmonary clearance at about 200 days postexposure.


Asunto(s)
Análisis por Activación , Polvo , Pulmón/metabolismo , Análisis de Activación de Neutrones , Análisis por Activación/instrumentación , Aerosoles , Contaminantes Atmosféricos/metabolismo , Animales , Cricetinae , Semivida , Análisis de Activación de Neutrones/instrumentación , Talco/metabolismo
18.
J Clin Invest ; 54(5): 1020-31, 1974 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-4421396

RESUMEN

The interactions of proinsulin with the insulin-specific receptors were investigated in purified rat liver plasma membranes. These studies were designed to characterize the binding of proinsulin to the insulin receptors, to search for proinsulin-specific receptor sites, and to examine the possibility of proinsulin conversion at the insulin receptor site. Proinsulin was only 3-5% as potent as insulin in binding to insulin receptors. Proinsulin reacted with all of the insulin-specific receptors, and direct binding studies of [(125)I]porcine proinsulin and [(125)I]rat proinsulin did not reveal proinsulin-specific receptor sites other than the insulin receptors in rat liver membranes. Quantitative data derived from steady-state and transient-state comparative binding studies of both [(125)I]proinsulin and [(125)I]insulin indicated that a 20-fold lower association rate constant essentially accounts for the reduced affinity of proinsulin for the insulin receptors. The possibility of proinsulin conversion at the insulin receptor sites was investigated. Material recovered from the membranes upon dissociation of the proinsulin-receptor complex was intact proinsulin and did not exhibit any conversion by a variety of analytical methods. These results indicate that the lower affinity of proinsulin for the insulin receptor in the liver is an intrinsic property of the proinsulin molecule. The lower uptake of proinsulin by the insulin receptor represents, in addition to a slower degradation of the prohormone, a further mechanism by which proinsulin exerts prolonged, albeit reduced, action in vivo.


Asunto(s)
Insulina/farmacología , Hígado/efectos de los fármacos , Proinsulina/farmacología , Receptores de Droga , Tejido Adiposo/citología , Adsorción , Animales , Arginina/análogos & derivados , Arginina/aislamiento & purificación , Arginina/metabolismo , Arginina/farmacología , Bovinos , Membrana Celular/efectos de los fármacos , Cromatografía DEAE-Celulosa , Cromatografía en Gel , Dipéptidos/metabolismo , Interacciones Farmacológicas , Electroforesis en Gel de Poliacrilamida , Glucosa/metabolismo , Cobayas/inmunología , Radioisótopos de Yodo , Hígado/ultraestructura , Oxidación-Reducción , Proinsulina/aislamiento & purificación , Proinsulina/metabolismo , Ratas , Porcinos , Talco/metabolismo , Factores de Tiempo
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