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1.
Environ Sci Pollut Res Int ; 30(50): 109438-109452, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37775628

RESUMEN

Plant diseases induced by various phytopathogens pose a significant threat to contemporary agricultural systems around the world. In modern agriculture, the use of pesticides is still a valuable and effective method to control plant diseases. However, agrochemicals are becoming less popular because of the accretion of toxic compounds perilous and potentially hazardous to humans and the environment. Taking into consideration these aspects, the present study was conducted to explore the biocontrol potential of an endophytic Streptomyces sp. SP5 bioformulations against Fusarium wilt. Three bioformulations were prepared using cell biomass and different carriers, i.e., B1 (talc-kaolin), B2 (MgSO4/glycerol/Na-alginate/talc/Ca-lignosulfonate), and B3 (calcium carbonate/CMC/talc). Apart from antagonistic action against Fusarium wilt, the influence of bioformulations on plant growth and systemic resistance was investigated by analyzing morphological parameters (root length, shoot length, root weight, shoot weight), biochemical parameters (photosynthetic pigments, non-enzymatic antioxidants), and induction of antioxidative enzymes, e.g., catalase (CAT), ascorbate peroxidase (APX), guaiacol peroxidase (GPX), and superoxide dismutase (SOD), in S. lycopersicum and C. annum seedlings. The results revealed that Streptomyces bioformulations effectively controlled Fusarium wilt in S. lycopersicum and C. annum (82.6-83.4% and 81.8-100%, respectively). Besides reducing disease prevalence, bioformulations significantly increased all the morphological parameters and increased the activity of antioxidative enzymes, i.e., CAT, APX, GPX, and SOD, in plants. The current findings display that bioformulations can be utilized as environment-friendly biocontrol agents against Fusarium wilt and also as plant growth promoters.


Asunto(s)
Capsicum , Fusarium , Solanum lycopersicum , Streptomyces , Humanos , Plantones , Talco/farmacología , Antioxidantes/farmacología , Superóxido Dismutasa , Enfermedades de las Plantas/prevención & control
2.
PeerJ ; 10: e13198, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35441060

RESUMEN

Introductions: In many areas, particularly in Asia, the oriental fruit fly Bactrocera dorsalis (Hendel) causes considerable fruit damage on various plants. The fruit fly causes significant economic losses every year due to reduced fruit quantity and quality as well as export restrictions. This study aimed to examine the potency of minerals in controlling the oriental fruit fly infestation in chili fruits. Methods: Experiments were conducted under laboratory and semi-field conditions using randomized block design. Ten minerals (i.e. kaolin, talc, zinc oxide, bentonite, sulfur, dolomite, calcium oxide, calcium hydroxide, calcium carbonate, and zeolite) and an untreated control were tested under laboratory conditions. Twenty chili fruits at a green stage were soaked in each mineral suspension (2%, w/v), air-dried, and placed in a trial cage (23-L plastic container) containing 20 female oriental fruit flies. In a semi-field bioassay using a screen cage (100 cm × 70 cm × 120 cm), 20 female oriental fruit flies were exposed to a fruit-bearing chili plant sprayed with mineral suspension. Results: Talc and calcium oxide significantly reduced the numbers of visiting fruit flies, oviposition holes, and eggs laid, as well as the percentage of infested chili fruits in a laboratory bioassay. Calcium hydroxide was substantially better than talc in controlling fruit fly infestation in a semi-field bioassay, although it was not significantly different from calcium oxide and calcium carbonate. Conclusion: Overall, calcium oxide is a viable option for the long-term control of the oriental fruit fly on chili fruits. Calcium oxide could be utilized as the push component of a push-pull strategy to manage oriental fruit fly infestation in chili fruits because of its potential to inhibit the number of visiting fruit flies and oviposition.


Asunto(s)
Talco , Tephritidae , Animales , Femenino , Talco/farmacología , Drosophila , Oviposición
3.
Biotechnol Bioeng ; 117(12): 3858-3875, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32808679

RESUMEN

Streptomyces spp. are a rich source for natural products with recognized industrial value, explaining the high interest to improve and streamline the performance of in these microbes. Here, we studied the production of pamamycins, macrodiolide homologs with a high activity against multiresistant pathogenic microbes, using recombinant Streptomyces albus J1074/R2. Talc particles (hydrous magnesium silicate, 3MgO·4SiO2 ·H2 O) of micrometer size, added to submerged cultures of the recombinant strain, tripled pamamycin production up to 50 mg/L. Furthermore, they strongly affected morphology, reduced the size of cell pellets formed by the filamentous microbe during the process up to sixfold, and shifted the pamamycin spectrum to larger derivatives. Integrated analysis of transcriptome and precursor (CoA thioester) supply of particle-enhanced and control cultures provided detailed insights into the underlying molecular changes. The microparticles affected the expression of 3,341 genes (56% of all genes), revealing a global and fundamental impact on metabolism. Morphology-associated genes, encoding major regulators such as SsgA, RelA, EshA, Factor C, as well as chaplins and rodlins, were found massively upregulated, indicating that the particles caused a substantially accelerated morphogenesis. In line, the pamamycin cluster was strongly upregulated (up to 1,024-fold). Furthermore, the microparticles perturbed genes encoding for CoA-ester metabolism, which were mainly activated. The altered expression resulted in changes in the availability of intracellular CoA-esters, the building blocks of pamamycin. Notably, the ratio between methylmalonyl CoA and malonyl-CoA was increased fourfold. Both metabolites compete for incorporation into pamamycin so that the altered availability explained the pronounced preference for larger derivatives in the microparticle-enhanced process. The novel insights into the behavior of S. albus in response to talc appears of general relevance to further explore and upgrade the concept of microparticle enhanced cultivation, widely used for filamentous microbes.


Asunto(s)
Macrólidos/metabolismo , Ingeniería Metabólica , Streptomyces , Streptomyces/genética , Streptomyces/metabolismo , Talco/química , Talco/farmacología
4.
Am J Respir Cell Mol Biol ; 62(3): 331-341, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31513749

RESUMEN

Hydrated magnesium silicate (or "talc" particles) is a sclerosis agent commonly used in the management of malignant pleural effusions, a common symptom of metastatic diseases, including lung cancers. However, the direct effects of talc particles to lung carcinoma cells, which can be found in the malignant pleural effusion fluids from patients with lung cancer, are not fully understood. Here, we report a study of the signaling pathways that can modulate the cell death and IL-6 secretion induced by talc particles in human lung carcinoma cells. We found that talc-sensitive cells have higher mRNA and protein expression of PI3K catalytic subunits α and ß. Further experiments confirmed that modulation (inhibition or activation) of the PI3K pathway reduces or enhances cellular sensitivity to talc particles, respectively, independent of the inflammasome. By knocking down specific PI3K isoforms, we also confirmed that both PI3Kα and -ß mediate the observed talc effects. Our results suggest a novel role of the PI3K pathway in talc-induced cell death and IL-6 secretion in lung carcinoma cells. These cellular events are known to drive fibrosis, and thus further studies of the PI3K pathway may provide a better understanding of the mechanisms of talc sclerosis in the malignant pleural space.


Asunto(s)
Adenocarcinoma/enzimología , Carcinoma de Pulmón de Células no Pequeñas/enzimología , Fosfatidilinositol 3-Quinasas Clase II/fisiología , Neoplasias Pulmonares/enzimología , Proteínas de Neoplasias/fisiología , Soluciones Esclerosantes/farmacología , Talco/farmacología , Factores de Transcripción/fisiología , Actinas/fisiología , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Muerte Celular , Línea Celular Tumoral , Fosfatidilinositol 3-Quinasas Clase II/biosíntesis , Fosfatidilinositol 3-Quinasas Clase II/genética , Resistencia a Medicamentos , Inducción Enzimática , Humanos , Interleucina-6/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Proteínas de Neoplasias/antagonistas & inhibidores , Derrame Pleural Maligno/química , Inhibidores de Proteínas Quinasas/farmacología , Subunidades de Proteína , Interferencia de ARN , ARN Mensajero/biosíntesis , ARN Mensajero/genética , ARN Neoplásico/biosíntesis , ARN Neoplásico/genética , ARN Interferente Pequeño/genética , Transducción de Señal , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/biosíntesis , Factores de Transcripción/genética
5.
Interact Cardiovasc Thorac Surg ; 30(3): 337-345, 2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-31858124

RESUMEN

Primary spontaneous pneumothorax (PSP) is one of the most common thoracic diseases affecting adolescents and young adults. Despite the high incidence of PSP and the availability of several international guidelines for its diagnosis and treatment, a significant behavioural heterogeneity can be found among those management recommendations. A working group of the Italian Society of Thoracic Surgery summarized the best evidence available on PSP management with the methodological tool of a systematic review assessing the quality of previously published guidelines with the Appraisal of Guidelines for Research and Evaluation (AGREE) II. Concerning PSP physiopathology, the literature seems to be equally divided between those who support the hypothesis of a direct correlation between changes in atmospheric pressure and temperature and the incidence of PSP, so it is not currently possible to confirm or reject this theory with reasonable certainty. Regarding the choice between conservative treatment and chest drainage in the first episode, there is no evidence on whether one option is superior to the other. Video-assisted thoracic surgery represents the most common and preferred surgical approach. A primary surgical approach to patients with their first PSP seems to guarantee a lower recurrence rate than that of a primary approach consisting of a chest drainage positioning; conversely, the percentage of futile surgical interventions that would entail this aggressive attitude must be carefully evaluated. Surgical pleurodesis is recommended and frequently performed to limit recurrences; talc poudrage offers efficient pleurodesis, but a considerable number of surgeons are concerned about administering this inert material to young patients. CLINICAL TRIAL REGISTRATION NUMBER: International Prospective Register of Systematic Reviews (PROSPERO): CRD42018084247.


Asunto(s)
Tubos Torácicos , Pleurodesia/métodos , Neumotórax/epidemiología , Talco/farmacología , Cirugía Torácica Asistida por Video/métodos , Salud Global , Humanos , Incidencia , Neumotórax/diagnóstico , Neumotórax/terapia
6.
Lung Cancer ; 137: 14-18, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31521977

RESUMEN

OBJECTIVES: Recent observations indicate a potential survival benefit in patients with malignant pleural effusion (MPE) who achieve successful pleurodesis in comparison to patients who experience effusion recurrence post pleurodesis. This study aimed to explore this observation using two datasets of patients with MPE undergoing talc pleurodesis. MATERIALS AND METHODS: Dataset 1 comprised patients who underwent talc pleurodesis at Oxford Pleural Unit for MPE. Dataset 2 comprised patients enrolled in the TIME1 clinical trial. Pleurodesis success was defined as absence of need for further therapeutic procedures for MPE in the three months following pleurodesis. Data on various clinical, laboratory and radiological parameters were collected and survival was compared according to pleurodesis outcome (success vs. failure) after adjusting for the aforementioned parameters. RESULTS: Dataset 1 comprised 60 patients with mean age 74.1±10.3 years. The most common primary malignancies were mesothelioma, breast and lung cancer. 29 patients (48.3%) achieved pleurodesis. The adjusted odds ratio (aOR) for poor survival with pleurodesis failure was 2.85 (95% CI 1.08-7.50, =p 0.034). Dataset 2 comprised 259 patients from the TIME1 trial. The mean age was 70.8±10.3 and the most common primary malignancies were mesothelioma, lung and breast cancer. Pleurodesis was successful in 205 patients (79%). aOR for poor survival was 1.62 (95% CI 1.09-2.39, p = 0.015). CONCLUSION: Achieving pleurodesis seems to impart a survival benefit in patients with MPE. Further studies are required to explore factors that may contribute to this phenomenon and to address the difference in survival between pleurodesis and indwelling pleural catheter interventions.


Asunto(s)
Antitranspirantes/farmacología , Neoplasias Pulmonares/mortalidad , Mesotelioma/mortalidad , Derrame Pleural Maligno/mortalidad , Pleurodesia/mortalidad , Talco/farmacología , Anciano , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Masculino , Mesotelioma/tratamiento farmacológico , Mesotelioma/patología , Mesotelioma Maligno , Derrame Pleural Maligno/tratamiento farmacológico , Derrame Pleural Maligno/patología , Pronóstico , Tasa de Supervivencia
7.
Curr Opin Pulm Med ; 25(4): 374-379, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30865037

RESUMEN

PURPOSE OF REVIEW: Talc remains a common sclerosant utilized for pleurodesis. However, the use of talc has documented complications and debate has persisted regarding the safety of talc as well as the differences in talc preparations available throughout the world. We sought to describe an up-to-date review of talc preparations available and the impact these preparations may have on the safety profile of talc. RECENT FINDINGS: Within laboratory-based examinations, talc particle size available within the United States appears to be more consistent with prior reported 'safe' particle sizes. The presence of talc within protein-based solutions appears to modify the overall milieu of the solution and likely results in particle aggregation. SUMMARY: The use of talc remains well accepted for pleurodesis as evidenced by inclusion by multiple guidelines. The medical fields' current understanding of talc and its basic interactions within the pleural space remain limited. Multiple questions related to the pleural space and pleurodesis remain unanswered.


Asunto(s)
Derrame Pleural Maligno/terapia , Pleurodesia , Talco , Humanos , Tamaño de la Partícula , Pleurodesia/efectos adversos , Pleurodesia/métodos , Soluciones Esclerosantes/química , Soluciones Esclerosantes/farmacología , Talco/química , Talco/farmacología , Estados Unidos
8.
J Drugs Dermatol ; 17(5): 566-570, 2018 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-29742190

RESUMEN

INTRODUCTION: Diaper dermatitis is a common condition that develops in the diaper area due to factors such as elevated moisture, increased skin surface pH, and exposure to irritants from urine and feces. These factors suggest interventions to prevent or treat diaper dermatitis such as exposing the skin to air, frequent diaper changes, and thorough cleansing of the diaper area. Barrier creams and powders also have a role in preventing and treating diaper dermatitis. We developed a cream-to-powder product with a formula based on corn starch and other natural ingredients for use in the diaper area. METHODS: Dye exclusion study: The barrier properties of the cream-to-powder product were assessed using a dye exclusion protocol. Skin color at treated and untreated forearm sites was measured at baseline and after exposure to crystal violet stain. The cream-to-powder product's ability to inhibit the water-soluble dye from reaching the skin was judged by comparing color changes at the treated and untreated sites. Tolerance-in-use study: The safety of the cream-to-powder product was assessed in a four-week tolerance-in-use study conducted in a group of 52 diaper-wearing infants and toddlers. Subjects' parents/guardians applied the cream-to-powder product at each diaper change. A pediatrician judged safety endpoints of erythema, dryness, and edema in the diaper area at baseline and at study end. Parents/guardians also completed a questionnaire at study end. These studies have complied with Good Clinical Practices (GCP/ICH). OUTCOMES: The cream-to-powder product prevented about 70% of the test dye from reaching the skin surface, demonstrating its ability to supplement the skin barrier. The tolerance-in-use study showed no statistically significant changes in any of the safety endpoints; there were no adverse events. Parents/guardians responses to the cream-to-powder product were overwhelmingly positive. Taken together, these results support that the cream-to-powder formulation is safe and effective for helping to prevent diaper dermatitis. J Drugs Dermatol. 2018;17(5):566-570.


Asunto(s)
Fármacos Dermatológicos/uso terapéutico , Dermatitis del Pañal/tratamiento farmacológico , Crema para la Piel/uso terapéutico , Piel/efectos de los fármacos , Talco/uso terapéutico , Administración Tópica , Adulto , Preescolar , Fármacos Dermatológicos/administración & dosificación , Fármacos Dermatológicos/farmacología , Dermatitis del Pañal/patología , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Crema para la Piel/administración & dosificación , Crema para la Piel/farmacología , Encuestas y Cuestionarios , Talco/administración & dosificación , Talco/farmacología , Resultado del Tratamiento , Adulto Joven
9.
Microb Cell Fact ; 17(1): 1, 2018 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-29306327

RESUMEN

BACKGROUND: Mushroom showed pellet, clump and/or filamentous mycelial morphologies during submerged fermentation. Addition of microparticles including Talc (magnesium silicate), aluminum oxide and titanium oxide could control mycelial morphologies to improve mycelia growth and secondary metabolites production. Here, effect of microparticle Talc (45 µm) addition on the mycelial morphology, fermentation performance, monosaccharide compositions of polysaccharides and enzymes activities associated with polysaccharide synthesis in G. frondosa was well investigated to find a clue of the relationship between polysaccharide biosynthesis and morphological changes. RESULTS: Addition of Talc decreased the diameter of the pellets and increased the percentage of S-fraction mycelia. Talc gave the maximum mycelial biomass of 19.25 g/L and exo-polysaccharide of 3.12 g/L at 6.0 g/L of Talc, and mycelial polysaccharide of 0.24 g/g at 3.0 g/L of Talc. Talc altered the monosaccharide compositions/percentages in G. frondosa mycelial polysaccharide with highest mannose percentage of 62.76 % and lowest glucose percentage of 15.22 % followed with the corresponding changes of polysaccharide-synthesis associated enzymes including lowest UDP-glucose pyrophosphorylase (UGP) activity of 91.18 mU/mg and highest UDP-glucose dehydrogenase (UGDG) and GDP-mannose pyrophosphorylase (GMPPB) activities of 81.45 mU/mg and 93.15 mU/mg. CONCLUSION: Our findings revealed that the presence of Talc significantly changed the polysaccharide production and sugar compositions/percentages in mycelial and exo-polysaccharides by affecting mycelial morphology and polysaccharide-biosynthesis related enzymes activities of G. frondosa.


Asunto(s)
Grifola/metabolismo , Micelio/efectos de los fármacos , Polisacáridos/biosíntesis , Talco/farmacología , Óxido de Aluminio/farmacología , Biomasa , Medios de Cultivo , Fermentación , Grifola/efectos de los fármacos , Silicatos de Magnesio/farmacología , Microesferas , Micelio/química , Micelio/crecimiento & desarrollo , Micelio/metabolismo , Polisacáridos/análisis , Polisacáridos/metabolismo , Talco/química , Titanio/farmacología
10.
Int J Biol Macromol ; 106: 955-962, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28830776

RESUMEN

The effects of six nucleating agents (NAs), i.e., orotic acid (OA), potassium salt of 3,5-bis(methoxycarbonyl)benzenesulfonate (LAK-301), substituted-aryl phosphate salts (TMP-5), talc (TALC), N'1,N'6-dibenzoyladipohydrazide (TMC-306) and N1,N1'-(ethane-1,2-diyl)bis(N2-phenyloxalamide) (OXA), on the crystallization behavior of poly(lactic acid) (PLA) were compared by DSC. Under the same dosing of 0.5wt%, the nucleation effect of the NAs for PLA declines in the order of TMC-306≈OXA>TALC≫TMP-5≈LAK-301≈OA. The nucleation efficiency (NE) of TMC-306 and OXA is around 50%, which is almost 2 times of the NE of TALC. In the best case of the PLA/TMC-0.5% sample, the half-time of crystallization decreases from 30s to 9s with decreasing the crystallization temperature from 120°C to 100°C, which is of great significance to the fast production of highly crystallized PLA materials. As high-efficient NAs, TMC-306 and OXA are able to accelerate the crystallization rate of PLA even upon fast cooling at 50°C/min, while make no difference on PLA crystal form, as identified by WAXD. DMA analysis shows that the storage modulus of PLA is significantly improved by TMC-306 and OXA.


Asunto(s)
Cristalización , Poliésteres/química , Polímeros/química , Benzamidas/química , Benzamidas/farmacología , Rastreo Diferencial de Calorimetría , Catálisis , Ácido Orótico/química , Ácido Orótico/farmacología , Poliésteres/síntesis química , Polímeros/síntesis química , Talco/química , Talco/farmacología , Temperatura , Difracción de Rayos X
11.
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
12.
Am Surg ; 82(10): 995-999, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27779992

RESUMEN

Malignant pleural effusions (MPE) are commonly managed with either pleural catheter (PC) or talc pleurodesis (TP). The aim of this study was to compare survival in MPE patients treated with either PC or TP. A retrospective review of our cancer center database was performed. Patients with metastatic cancer and MPE were analyzed. Demographic and clinical data were tabulated and compared. A total of 238 patients with MPE treated by either PC or TP were included. Of these, 79 patients comprised the PC group and 159 the TP group. PC had a higher incidence of advanced disease (stage III or IV) at initial diagnosis compared with TP (70.9% vs 57.2%, P = 0.05). TP had a longer postprocedure length of stay compared with PC (7.1 vs 5.0 days, P = 0.02); however, overall length of stay was similar (9.7 vs 11.1 days, P = 0.34). Readmissions were significantly lower in TP (11.9% vs 22.8%, P = 0.04). Mean survival was higher in TP compared with PC (18.7 vs 4.1 months, P < 0.001). Patients with metastatic cancer and MPE treated with TP had significantly higher survival compared with PC. This is likely related to a greater disease burden in PC, as 70 per cent of patients in this group had stage III or IV disease on initial presentation.


Asunto(s)
Drenaje/métodos , Derrame Pleural Maligno/mortalidad , Derrame Pleural Maligno/terapia , Pleurodesia/métodos , Talco/farmacología , Anciano , Catéteres de Permanencia , Bases de Datos Factuales , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Cuidados Paliativos/métodos , Derrame Pleural Maligno/diagnóstico , Pleurodesia/mortalidad , Estudios Retrospectivos , Medición de Riesgo , Análisis de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
13.
J Sci Food Agric ; 96(10): 3292-9, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26847164

RESUMEN

The maximization of both extraction yield and extra virgin olive oil quality during olive processing are the main objectives of the olive oil industry. As regards extraction yield, it can be improved by both acting on time/temperature of malaxation and using physical coadjuvants. It is well known that, generally, increasing temperature of malaxation gives an increase in oil extraction yield due to a reduction in oily phase viscosity; however, high malaxation temperature can compromise the nutritional and health values of extra virgin olive oil, leading to undesirable effects such as accelerated oxidative process and loss of volatile compounds responsible for oil flavor and fragrance. The addition of physical coadjuvants in olive oil processing during the malaxation phase, not excluded by EC regulations owing to its exclusively physical action, is well known to promote the breakdown of oil/water emulsions and consequently make oil extraction easier, thus increasing the yield. Among physical coadjuvants, micronized natural talc is used for olive oil processing above all for Spanish and Italian olive cultivars. The quality of extra virgin olive oil depends on numerous variables such as olive cultivar, ripeness degree and quality, machines utilized for processing, oil storage conditions, etc. However, the coadjuvants utilized in olive processing can also influence virgin olive oil characteristics. The literature highlights an increase in oil yield by micronized natural talc addition during olive processing, whereas no clear trend was observed as regards the chemical, nutritional and sensory characteristics of extra virgin olive oil. Although an increase in oil stability was reported, no effect of talc was found on the evolution of virgin olive oil quality indices during storage. © 2016 Society of Chemical Industry.


Asunto(s)
Manipulación de Alimentos/métodos , Calidad de los Alimentos , Aceite de Oliva/química , Talco/farmacología , Estabilidad de Medicamentos , Emulsiones , Calor , Hidrólisis , Italia , Valor Nutritivo , Oxidación-Reducción , Fenoles/análisis , Gusto , Tocoferoles/análisis , Viscosidad , Compuestos Orgánicos Volátiles/análisis
14.
Bioprocess Biosyst Eng ; 39(2): 323-30, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26658984

RESUMEN

Lactic acid has a wide industrial application area and can be produced by fungal strains. However, excessive bulk growth form of fungi during the fermentations is a major problem, which limits the fermentation performance. Microparticles are excellent tools to prevent bulk fungal growth and provide homogenized fermentation broth to increase uniformity and the prediction performance of the models. Therefore, in this study, addition of aluminum oxide and talcum microparticles into fermentations was evaluated to enhance the production of lactic acid by Rhizopus oryzae. The results showed that the bulk fungal growth was prevented and the lactic acid concentration increased from 6.02 to 13.88 and 24.01 g/L, when 15 g/L of aluminum oxide or 10 g/L of talcum was used, respectively, in the shake-flask fermentations. Additionally, substrate concentration, pH, and agitation were optimized in the bioreactors using response surface methodology, and optimum values were determined as 126 g/L of glucose, 6.22 pH, and 387 rpm, respectively. Under these conditions, lactic acid production further increased to 75.1 ± 1.5 g/L with 10 g/L of talcum addition. Also, lactic acid production and glucose consumption in the batch fermentation were successfully modeled with modified Gompertz model and modified logistic model. RMSE and MAE values for lactic acid production were calculated as 2.279 and 1.498 for the modified Gompertz model; 3.6 and 4.056 for the modified logistic model. Additionally, modified logistic model predicted glucose consumption with -2.088 MAE and 2.868 RMSE, whereas these values were calculated as 2.035 and 3.946 for the modified Gompertz model.


Asunto(s)
Óxido de Aluminio/farmacología , Ácido Láctico/biosíntesis , Modelos Biológicos , Rhizopus/crecimiento & desarrollo , Talco/farmacología , Concentración de Iones de Hidrógeno
15.
Int J Exp Pathol ; 96(2): 111-5, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25885949

RESUMEN

There are several methods used for non-surgical sterilization in birth control including quinacrine, trichloroacetic acid (TCA), erythromycin, tetracycline, silver nitrate and talcum powder. Among these, talcum powder, TCA and silver nitrate are the most commonly used. However, the toxic and carcinogenic activities of these chemicals in ovarian tissue have been poorly elucidated. This study demonstrates the expression levels of antioxidant, apoptotic and anti-apoptotic genes after administration of talc powder, TCA and silver nitrate for non-surgical sterilization in female rat models. The expression changes of some microRNAs (miR-15b, miR-21, miR-34a and miR-98) that play key roles in the apoptosis pathway were also included. All expression analyses were evaluated with real-time PCR. The expression levels of all genes appeared to be upregulated in the talcum powder group, but the results were not statistically significant. Increased expression of Gsr and Sod1 genes was statistically significant in the talcum powder group. In TCA and silver nitrate group, expression of all genes was appeared to be elevated but only the Gsr expression was statistically significant in the TCA-administrated group; there were no statistically significant changes in the silver nitrate group. miRNA expression levels were increased in talcum powder and TCA-administrated groups, but these results were not significant. Expression levels of miR-15b, miR-21 and miR-98 in the silver nitrate group were significantly increased. Consequently, these chemicals appear to be non-carcinogenic agents for rat ovarian tissue which do not induce apoptosis. However, talcum powder and TCA can be considered as agents that are toxic to ovarian tissue.


Asunto(s)
Apoptosis/efectos de los fármacos , MicroARNs/genética , Ovario/patología , ARN Mensajero/genética , Nitrato de Plata/farmacología , Esterilización Reproductiva/métodos , Talco/farmacología , Ácido Tricloroacético/farmacología , Animales , Antioxidantes/metabolismo , Apoptosis/genética , Femenino , MicroARNs/efectos de los fármacos , MicroARNs/metabolismo , Modelos Animales , Ovario/efectos de los fármacos , Ovario/metabolismo , ARN Mensajero/efectos de los fármacos , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética
16.
World J Microbiol Biotechnol ; 31(2): 337-44, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25504372

RESUMEN

Endophytic fungi are plant beneficial rhizospheric microorganisms often applied as bioinoculants for enhanced and disease-free crop production. The objectives of the present work were to develop a carrier-based formulation of root endophyte Piriformospora indica as a bioinoculant. Powder formulation of four different carrier materials viz., talcum powder, clay, sawdust and bioboost (organic supplement) were evaluated and a talc-based formulation was optimized for a longer shelf life with respect to microbial concentration, storage temperature and biological activity. Finally the effect of optimized talc formulation on plant productivity was determined. The application dosages were optimized by studies on plant growth parameters of Phaseolus vulgaris L. plants under green house conditions. Five percent formulation (w/w) of talcum powder was observed to be the most stable at 30 °C with 10(8) CFU g(-1) and effective for a storage period of 6 months. The application of this optimized formulation resulted in increase of growth parameters of P. vulgaris L. and better adaptation of plants under green house conditions.


Asunto(s)
Basidiomycota/fisiología , Phaseolus/crecimiento & desarrollo , Phaseolus/microbiología , Silicatos de Aluminio/farmacología , Arcilla , Endófitos , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/microbiología , Talco/farmacología
17.
Neotrop Entomol ; 41(3): 223-31, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23950047

RESUMEN

The potato tuberworm Phthorimaea operculella (Zeller) is an important agricultural pest that causes significant economic losses to potato growers worldwide. The addition of an effective method of biological control for the potato tuberworm is greatly needed, and is currently unavailable in Brazil. The granulosis virus (Baculoviridae) is a promising biological control agent to protect post-harvest potatoes and in storage from the potato tuberworm. However, the control measure must be economically feasible. Liquid suspensions of a granulosis virus applied alone or in mixture with two commercial neem oil-based products (DalNeem™ and NeemAzal™), and a dry powder formulation of viral granules were evaluated for control of potato tuberworm larvae by treating potato tubers under laboratory conditions. High larval mortality (86.7%) was achieved when DalNeem and virus were applied together at 4 mg of azadirachtin/L and 10(4) occlusion bodies (OBs)/mL, respectively. This combination resulted in ≥50% efficacy in relation to their counterparts alone. Conversely, NeemAzal did not enhance virus effectiveness against larvae of the potato tuberworm. The talc-based virus formulation was used for dusting seed tubers at different concentrations and resulted in 100% larval mortality at 5 × 10(8) OBs/g. Formulated and unformulated virus provided 50% mortality at 166 OBs/g and at 5.0 × 10(5) OBs/mL, respectively. As a result, talc-based virus formulation had a better control efficiency on potato tuberworm than the aqueous virus suspension. The granulosis virus combined with DalNeem at low rates or formulated with talc powder is a viable option to control the potato tuberworm under storage conditions.


Asunto(s)
Azadirachta , Granulovirus , Insecticidas , Lepidópteros/efectos de los fármacos , Lepidópteros/fisiología , Limoninas , Control Biológico de Vectores/métodos , Solanum tuberosum/parasitología , Talco/farmacología , Animales
18.
J Biomed Nanotechnol ; 7(1): 112-3, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21485829

RESUMEN

Particle size reduction of talc from micro- to nanoscale gradually enhanced its cytotoxicity however its inflammatory potential is still not explored. In the current study we observed increased TNF-alpha, IL-1beta and IL-6 mRNA levels in macrophages exposed to Nano-Talc (NT). Further, NT particles also showed constituent phosphorylation of both p38 and ERK1/2 pathway however JNK phosphorylation was transient. Pre-treatment of macrophages with p38 and ERK1/2 inhibitors either alone or in combination showed significant reduction in TNF-alpha mRNA stability, clearly suggesting their role in TNF-alpha mRNA stabilization and expression. Our observations clearly demonstrated the inflammatory potential of NT particles which might be at least partial and potential mechanism in talc mediated pathogenecity in the exposed population.


Asunto(s)
Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Nanoestructuras/administración & dosificación , ARN Mensajero/metabolismo , Talco/farmacología , Factor de Necrosis Tumoral alfa/metabolismo , Células Cultivadas , Humanos
19.
Surg Today ; 41(1): 111-4, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21191701

RESUMEN

PURPOSE: To define the changes in the pleural cavity after pleurodesis induced by talc or OK-432. METHODS: A total of 30 rats were divided into three groups: a normal saline group (control group, n = 10), a group administered 400 mg/kg talc (talc group, n = 10), and a group administered 0.3 KE/kg OK-432 (OK-432 group, n = 10). Pleural cavities were examined and scored on the 30th day after the intrapleural administration of each agent. RESULTS: Both the talc group and OK-432 group showed significantly higher macroscopic or microscopic pleurodesis scores than the control group (P < 0.05). Upon microscopic evaluation, the pleurodesis scores in the talc group were significantly higher than those in the OK-432 group (P < 0.01).The majority of the pleural thickness was found on the visceral pleura, and the parietal pleura was very thin. The thickness of the visceral pleura in the talc group was significantly higher than that in the OK-432 group (P < 0.005). Pathologically, the pleural thickening in the talc group consisted of fibrous tissue with injury of the pleural mesothelium, and talc particles were seen in the submesothelial fibrotic tissue and inside the alveoli. CONCLUSIONS: Talc pleurodesis induces more marked changes in the pleural cavity than OK-432-induced pleurodesis.


Asunto(s)
Antineoplásicos/farmacología , Antitranspirantes/farmacología , Picibanil/farmacología , Cavidad Pleural/efectos de los fármacos , Pleurodesia , Talco/farmacología , Animales , Masculino , Pleura/efectos de los fármacos , Pleura/patología , Cavidad Pleural/patología , Ratas , Ratas Wistar
20.
Respiration ; 80(3): 220-7, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20460881

RESUMEN

BACKGROUND: Medical thoracoscopy (MT) is a procedure considered as minimally invasive. The safety of the procedure has been questioned recently in fragile patients, but no explanation of the pathophysiologic mechanism has been given. Although MT is applied by respiratory physicians who are also dealing with patients with impairment of lung function, it is surprising that there are no data concerning lung mechanics and function in this patient population. OBJECTIVES: To assess respiratory muscle strength and lung function in patients undergoing MT, with or without talc pleurodesis. METHODS: We measured prospectively the maximal inspiratory (MIP) and expiratory pressures (MEP) and lung function of 29 patients who underwent MT before (baseline) and on consecutive days following MT. RESULTS: 29 patients participated with a mean age of 63.6 +/- 13.8 (range 20-79) years. 15 of them underwent talc pleurodesis and 14 diagnostic thoracoscopy. Mean MIP and MEP values were significantly decreased on day (d) 1 after MT compared to baseline (p = 0.03 and p = 0.007, respectively) and recovered on d2. FEV(1) and FVC mean values were also found significantly decreased on d1 after MT compared to baseline (p < 0.0001 and p = 0.0003, respectively) and recovered on d2. Patients with pleurodesis presented with lower mean values of the studied parameters than those with diagnostic thoracoscopy. No significant complication was associated with the procedure. CONCLUSION: Respiratory muscles and lung function can be temporarily affected from MT. Physicians should be alert, especially in patients with already impaired lung function, where any further impairment could be detrimental.


Asunto(s)
Pleurodesia/efectos adversos , Músculos Respiratorios/fisiología , Toracoscopía/efectos adversos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Pruebas de Función Respiratoria , Talco/farmacología , Adulto Joven
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