Evaluación preliminar de técnicas de crioconservación en una accesión de Solanum phureja

En el Centro de Investigación Tibaitatá de Corpoica se llevan a cabo ensayos para determinar los mejores métodos de crioconservación de los materiales que integran la Colección Central Colombiana de Papa; ésta se encuentra constituida por 1.098 accesiones de las cuales 151 corresponden a Solanum phureja (98 conservadas in vitro y 53 en campo), especie que se considera estratégica por poseer genes de resistencia a Phytophtora infestans y por ser un importante recurso alimenticio para la población colombiana. A tal fin se evaluaron las técnicas de encapsulación-deshidratación y encapsulación-vitrificación, reportadas en la actualidad para Solanum spp., implementando algunos ajustes y dedicando especial atención a las etapas previas a la congelación en cuanto la selección del material vegetal y los medios de propagación, la calidad del tejido, la encapsulación de los ápices, la concentración y el tiempo de exposición a sacarosa, la deshidratación en sílica gel y el efecto de la solución cargadora y de las soluciones PVS2 y PVS4. Fue posible establecer que la calidad de explante y el medio de recuperación determinaron el éxito del proceso de crioconservación. El medio de preacondicionamiento MS, suplementado con 0,18 μM BAP y 0,28 μM durante 3 a 5 días, permitió mejorar la calidad del tejido después del corte. Además, la suplementación del alginato con 0,004 mg·L-1 BAP y 0,04 mg·L-1 AG3, incidió positivamente en la respuesta de los ápices en las etapas previas al congelamiento. Se destaca que S. phureja es muy susceptible a condiciones de estrés físico y químico, razón por la cual la tasa de recuperación después del congelamiento fue de 10%. Preliminary evaluation of cryoconservation techniques in an accession of Solanum phureja The Tibaitatá Research Center of Corpoica is the repository of the main Colombian potato germplasm collection with 1098 accessions, 151 belonging to Solanum phureja (98 preserved in vitro and 53 in the field), a key species because it posses resistant genes against Phytophtora infestans and because it is an important food resource for the Colombian population. There crioconservation methods are evaluated to determine the best conservation practices. For this purpose, encapsulation-dehydration and encapsulationvitrification techniques were evaluated as reported for the Solanum species, adjusting methodologies and paying especial attention to tissue selection and quality, propagation media, apex encapsulation, concentration and time exposure to sucrose, dehydration in silica gel, and the effect of charger and PVS2 and PVS4 solutions, previous to freezing. Results indicated that explant quality and recuperation media determined the success in the crioconservation process. A preconditioning M&S medium supplemented with 0.18 μM of BAP and 0.28 μM of GA3 during 3 to 5 days allowed for tissue quality improvement after excision. Furthermore, alginate supplemented with 0.004 mg·L-1 of BAP and 0.04 mg·L-1 of GA3 positively enhanced the response of shoot tips during steps previous to freezing. Of importance in this study, Solanum phureja is highly susceptible to physical and chemical stress, and the reason why after freezing the recovery rate was only 10%.

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Pilocarpine hydrochloride liposomes: characterization in vitro and preliminary evaluation in vivo in rabbit eye

Journal of Microencapsulation ◽

10.3109/02652048409049359 ◽

1984 ◽

Vol 1 (3) ◽

pp. 203-216 ◽

Cited By ~ 24

Author(s):

S. Benita ◽

J. D. Plenecassagne ◽

G. Cavé ◽

D. Drouin ◽

P. Le Hao Dong ◽

...

Keyword(s):

Preliminary Evaluation ◽

Rabbit Eye

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In vitro 19-norandrogen synthesis by equine placenta requires the participation of aromatase

Journal of Endocrinology ◽

10.1677/joe.0.1440517 ◽

1995 ◽

Vol 144 (3) ◽

pp. 517-525 ◽

Cited By ~ 10

Author(s):

S Moslemi ◽

P Silberzahn ◽

J-L Gaillard

Keyword(s):

Silica Gel ◽

Aromatase Inhibitors ◽

Column Chromatography ◽

Microsomal Fraction ◽

Specific Activity ◽

Reverse Phase Hplc ◽

Reverse Phase ◽

Term Placenta ◽

Flow Detector

Abstract Explants of equine full-term placenta have been shown to synthesize 19-norandrogens from labelled androgens. Steroid metabolites were purified by silica-gel column chromatography then analysed and quantified by C18-reverse-phase HPLC coupled to a radioactive flow detector. 19-Norandrostenedione was subsequently recrystallized to constant specific activity, providing unequivocal evidence of its synthesis by the equine placenta. 19-Norandrostenedione synthesis appeared to be localized in the microsomal fraction. Regardless of the substrate used, formation of 19-norandrogens was far weaker than that of oestrogens; moreover, the yield of 17-oxosteroids produced was much greater than that of 17β-hydroxysteroids, suggesting the presence of a dehydrogenase with predominant oxidative activity. Sulphoconjugated steroids formed were less than 0·5% of total steroids. Although 19-nortestosterone could not be generated by equine purified aromatase incubated with labelled testosterone, the synthesis of 19-norandrogens and oestrogens by equine placental explants was blocked by two specific aromatase inhibitors, 4-hydroxyandrostenedione and fadrozole. Our results provide evidence for a placental origin of at least a part of the 19-norandrogens previously identified in the blood of the pregnant mare. Furthermore, it is suggested that 19-norandrogen biosynthesis would involve the enzymatic metabolism of 19-oxygenated androgens formed by equine aromatase. Journal of Endocrinology (1995) 144, 517–525

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Preliminary In Vitro Wear Assessment of Ceramic Cemented Femoral Components Coupled with Polyethylene Menisci

Materials ◽

10.3390/ma14092112 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2112

Author(s):

Saverio Affatato ◽

Paolo Erani ◽

Maurizio Fersini ◽

Vincenzo Contaldi ◽

Anna Rita Terrizzi ◽

...

Keyword(s):

Surface Roughness ◽

Wear Resistance ◽

Monoclinic Phase ◽

Calf Serum ◽

Wear Test ◽

Clinical Test ◽

Preliminary Evaluation ◽

Before And After ◽

Roughness Measurements

Success of total knee replacement (TKR) depends on the prosthetic design and materials. The use of metal components is well established with the disadvantage of allergic reactions. Ceramics have been recently proposed because of high wear resistance, excellent biocompatibility, wettability, and suitable mechanical properties. This study was aimed at investigating in vitro wear resistance of Zirconia Toughened Alumina (ZTA)/Ultra-high-molecular-weight polyethylene (UHMWPE) of TKR femoral components. An in vitro protocol was designed with the application of relevant load profile, 6-degrees-of-freedom knee simulator, and 8 × 105 cycles on the ZTA/UHMWPE configuration under bovine calf serum. Before and after wear test, the femoral components were investigated by using the Scanning Electron Microscope (SEM) and the X-Ray Diffraction (XRD) analyses, and stylus surface roughness measurements. The proposed pre-clinical test yielded repeatable results. In particular, gravimetric results showed that, after 8 × 105 cycles, the mean weight loss of the polyethylene mobile components is 5.3 ± 1.1 mg. The surface roughness measurements (Ramax) performed after the wear test showed no significant variation on the UHMWPE menisci. A slight increase of roughness has been found on the ZTA (0.02 µm before wear test, 0.28 µm after the test). SEM observations did not show significant modification of the surface morphology. Tetragonal to monoclinic phase ratio was measured by XRD before and after wear test to evaluate stability of tetragonal ZrO2 phase. Minimal conversion of tetragonal to monoclinic phase was found from 5.4 to 8%. Although this study is a preliminary evaluation limited to in vitro tests, it provides novel pre-clinical indications about the potential of ceramic TKR femoral components.

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Antifungal activity of Trichoderma harzianum and T. koningiopsis against Fusarium solani in seed germination and vigor of Miahuateco chili seedlings

Revista Mexicana de Fitopatología Mexican Journal of Phytopathology ◽

10.18781/r.mex.fit.2101-5 ◽

2021 ◽

Vol 39 (2) ◽

Author(s):

Leydi Miguel-Ferrer ◽

Omar Romero-Arenas ◽

Petra Andrade-Hoyos ◽

Primo Sánchez-Morales ◽

José Antonio Rivera-Tapia ◽

...

Keyword(s):

Antifungal Activity ◽

Seed Germination ◽

Trichoderma Harzianum ◽

Fusarium Solani ◽

Para Determinar ◽

Santa Maria

El chile es la segunda hortaliza de mayor producción en México. El objetivo de la investigación fue evaluar la actividad antagónica in vitro e in vivo de Trichoderma harzianum (T-H4) y T. koningiopsis (T-K11) versus Fusarium solani (MX-MIC 798) en la germinación y establecimiento de plántula de chile Miahuateco. Se utilizó la técnica de cultivo dual para determinar el porcentaje de inhibición de crecimiento radial (PICR) de la cepa MX-MIC 798. Además, se analizó el porcentaje de germinación en semillas de chile Miahuateco en vivero, así como la mortalidad de plántulas y grado de severidad a los 40 días después del trasplante (ddt) en Santa María Tecomavaca, Oaxaca, a través de biocontrol y control químico (Mancozeb 80®). La cepa T-H4 presentó el nivel antagónico PICR más alto (53.3%) in vitro y clase II en la escala de Bell, asimismo obtuvo 82% de germinación en semillas de chile Miahuateco en vivero y 48% de mortalidad en campo; de manera que igualó al control químico y superó a T. koningiopsis T-K11. La actividad antifúngica de Trichoderma spp., ofrecen una alternativa para el biocontrol de la marchitez y necrosis en raíz del cultivo de chile Miahuateco causada por F. solani MX-MIC 798.

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SYNTHESIS AND CHARACTERIZATION IN VITRO ANTIMICROBIAL AND CYTOTOXICITY TESTING OF OXALIC ACID-DERIVED CADMIUM CHELATING AGENTS

International Journal of Pharmacy and Pharmaceutical Sciences ◽

10.22159/ijpps.2018v10i7.26034 ◽

2018 ◽

Vol 10 (7) ◽

pp. 80

Author(s):

Daisy Selasteen F ◽

Alfred Cecil Raj S ◽

Alagappa Moses A

Keyword(s):

Antimicrobial Activity ◽

Silica Gel ◽

Optical Conductivity ◽

Cancer Cell Line ◽

Uv Spectra ◽

Diffusion Method ◽

Spectral Studies ◽

Cervical Cancer Cell Line ◽

Cell Line Hela

Objective: The aim of this study is to investigate the growth, structure, spectral, solubility and biological activity of sodium cadmium oxalate dehydrate (NaCdOx) and cadmium oxalate trihydrate (CdOx) crystals prepared by a single diffusion method in the silica gel medium.Methods: The present crystals were grown using single diffusion methods and tested for XRD, UV absorption (190 to 1100 mm) and solubility (distilled water at 20-29 °C) studies. The antimicrobial efficacy of the grown samples at various concentrations (25, 50, 75 and 100 μg/ml) was studied against Streptococcus, (G+Ve), Pseudomonas aeruginosa (G-Ve) and Candida albicans (antifungal). The cytotoxicity evolution was carried out against human cervical cancer cell line (HeLa) using MTT assays.Results: The existing single crystals were successfully grown by silica gel technique. The solubility of sodium cadmium oxalate dehydrate (NaCdOx) was moderately good in deionized warm water. The FTIR spectral studies confirmed the chelating bands of the present samples and UV spectra showed the better the optical conductivity of as-grown crystals. The complexes showed good antimicrobial activity against all tested microbial strains and they exhibited a decrease in cytotoxicity activity.Conclusion: The gel method was suitable to grow metal complexes of legend crystals. The modification of structural properties of cadmium oxalate trihydrate (CdOx) by sodium doping was much improved the solubility, anticancer, antimicrobial activity and polarization by the high optical conductivity of sodium cadmium oxalate dehydrate (NaCdOx) compound. Hence sodium cadmium oxalate dehydrate (NaCdOx) might be a candidate for biomedical applications.

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Antimicrobial activity of extracellular metabolites from antagonistic bacteria isolated from potato (Solanum phureja) crops

Summa Phytopathologica ◽

10.1590/0100-5405/1953 ◽

2014 ◽

Vol 40 (3) ◽

pp. 212-220 ◽

Cited By ~ 7

Author(s):

Sinar David Granada García ◽

Antoni Rueda Lorza ◽

Carlos Alberto Peláez

Keyword(s):

Antimicrobial Activity ◽

Cyclic Peptide ◽

Biological Activities ◽

Pathogenic Fungi ◽

Antagonistic Activity ◽

Solanum Phureja ◽

Dual Culture ◽

Crude Extracts ◽

Extracellular Metabolites

Microorganisms for biological control are capable of producing active compounds that inhibit the development of phytopathogens, constituting a promising tool toob tain active principles that could replace synthetic pesticides. This study evaluatedtheability of severalpotentialbiocontrol microorganismsto produce active extracellular metabolites. In vitro antagonistic capability of 50 bacterial isolates from rhizospheric soils of "criolla" potato (Solanum phureja) was tested through dual culture in this plant with different plant pathogenic fungi and bacteria. Isolates that showed significantly higher antagonistic activity were fermented in liquid media and crude extracts from the supernatants had their biological activities assessed by optical density techniques. Inhibitory effecton tested pathogens was observed for concentrations between 0.5% and 1% of crude extracts. There was a correlation between the antimicrobial activity of extracts and the use of nutrient-rich media in bacteria fermentation. Using a bioguided method, a peptidic compound, active against Fusarium oxysporum, was obtained from the 7ANT04 strain (Pyrobaculum sp.). Analysis by nuclear magnetic resonance and liquid chromatography coupled to mass detector evidenced an 11-amino acid compound. Bioinformatic software using raw mass data confirmed the presence of a cyclic peptide conformed by 11 mostly non-standard amino acids.

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Variability of in vitro ruminal fermentation and methanogenic potential in the pasture legume biserrula (Biserrula pelecinus L.)

Crop and Pasture Science ◽

10.1071/cp13073 ◽

2013 ◽

Vol 64 (4) ◽

pp. 409 ◽

Cited By ~ 7

Author(s):

Bidhyut Kumar Banik ◽

Zoey Durmic ◽

William Erskine ◽

Phillip Nichols ◽

Kioumars Ghamkhar ◽

...

Keyword(s):

Core Collection ◽

Volatile Fatty Acids ◽

Germplasm Collection ◽

Red Clover ◽

Subterranean Clover ◽

Ruminal Fermentation ◽

Rumen Microbes ◽

Pasture Legumes ◽

Pasture Legume

Biserrula (Biserrula pelecinus L.) is an important annual pasture legume for the wheatbelt of southern Australia and has been found to have lower levels of methane output than other pasture legumes when fermented by rumen microbes. Thirty accessions of the biserrula core germplasm collection were grown in the glasshouse to examine intra-specific variability in in vitro rumen fermentation, including methane output. One biserrula cultivar (Casbah) was also grown at two field locations to confirm that low methanogenic potential was present in field-grown samples. All of the biserrula accessions had significantly reduced methane [range 0.5–8.4 mL/g dry matter (DM)] output compared with subterranean clover (28.4 mL/g DM) and red clover (36.1 mL/g DM). There was also significant variation in fermentability profiles (except for volatile fatty acids) among accessions of the core collection. Methanogenic potential exhibited 86% broad-sense heritability within the biserrula core collection. The anti-methanogenic and gas-suppressing effect of biserrula was also confirmed in samples grown in the field. In conclusion, biserrula showed variability in in vitro fermentation traits including reduced methane production compared with controls. This bioactivity of biserrula also persists in the field, indicating scope for further selection of biserrula as an elite methane-mitigating pasture.

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Initial Design and Evaluation of a Pediatric Intra-Cardiac Camera System for Ventricular Septal Defects

Journal of Medical Devices ◽

10.1115/1.4005778 ◽

2012 ◽

Vol 6 (1) ◽

Author(s):

Mark E. Rentschler ◽

Keir D. Hart ◽

Max B. Mitchell

Keyword(s):

Left Ventricular ◽

Primary Objective ◽

Preliminary Evaluation ◽

Design Development ◽

Ventricular Septal Defects ◽

Camera System ◽

Surgical Closure ◽

Septal Defects ◽

Commercial Device

The primary objective of this project is to design, fabricate, and test a small, integrated camera system for aiding in the visualization and surgical repair of certain types of ventricular septal defects (VSD), in pediatric patients. Currently, no purpose-designed commercial device to view VSDs from the left ventricle of the heart exists. The left ventricular perspective is ideal for obtaining an unobstructed view of the VSD. This VSD camera device would also provide a platform for passing a suture through the hole in the ventricular septum, with future work implementing additional tools capable of more advanced tasks. This camera device will help solve some of the major issues currently associated with cardiac imaging and surgical closure of VSDs in newborns and young children This paper examines the design development and preliminary evaluation of a proof of concept device. Included are preliminary results of image quality comparisons, design details of a pediatric-specific VSD camera device, and initial outcomes from in vitro testing.

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Fistulación en bovinos y uso de la técnica de degradabilidad ruminal para análisis de alimentos

Nutrición Animal Tropical ◽

10.15517/nat.v14i2.45167 ◽

2020 ◽

Vol 14 (2) ◽

pp. 209-229

Author(s):

Jorge Alberto Elizondo-Salazar ◽

Cynthia Rebeca Monge-Rojas

Keyword(s):

Para Determinar ◽

In Sacco

La calidad nutritiva de los alimentos o ingredientes utilizados para la alimentación de los rumiantes está en función del nivel de consumo, de la degradabilidad a nivel ruminal, de la digestibilidad, de la concentración de nutrientes y de la eficiencia con que estos pueden ser metabolizados y utilizados. Una vez ingeridos los alimentos, la degradabilidad hace referencia a la cantidad de alimento que desaparece en el rumen por acción de los microorganismos presentes. La degradación ruminal es crucial en el suministro de nutrientes de la dieta para satisfacer las demandas de los microorganismos y de los tejidos corporales de los animales. Por lo tanto, es esencial estudiar la dinámica de la degradación ruminal de los alimentos antes de su uso potencial para formular raciones apropiadas para los rumiantes. Entre los muchos métodos que se han utilizado en el pasado, el método in sacco ha sido el método más eficaz para estudiar la degradación del rumen; sin embargo, el uso de este método es cada vez menos frecuente debido a sus implicaciones para el bienestar animal. Si bien se han probado muchos métodos in vitro como posibles alternativas al método in sacco, no se ha podido eliminar la necesidad de utilizar animales fistulados para obtener el licor o líquido ruminal. La canulación del rumen se puede realizar en un animal sano con un gasto mínimo. La cirugía no es más difícil que la mayoría de los otros procedimientos quirúrgicos de rutina realizados por veterinarios. Un animal canulado o fistulado proporciona además una fuente de contenido ruminal a largo plazo que se puede utilizar fácilmente para transfaunar compañeras del hato que han sufrido diversos trastornos digestivos. El objetivo de este trabajo es presentar, de manera resumida, los diferentes pasos en la fistulación de una vaca y detallar el uso de la técnica in vivo o in sacco para determinar la degradabilidad ruminal de los alimentos o ingredientes.

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Evaluación de las Técnicas Directas e Indirectas para determinar la precisión de la adaptación marginal, in vitro, de una restauración implanto-soportda

Crea Ciencia Revista Científica ◽

10.5377/creaciencia.v0i10.8181 ◽

2019 ◽

pp. 37-47

Author(s):

Natalia Chávez De Rivera ◽

Rosa Escolero De Nieto ◽

Alejandro José Colorado ◽

Hugo Alfredo Saravia ◽

Jorge Alberto Flores ◽

...

Keyword(s):

El Salvador ◽

Para Determinar

La presente investigación experimental in vitro, se realizó en la Escuela de Posgrado de Odontología de la Universidad Evangélica de El Salvador, para evaluar la adaptación marginal que proveen las técnicas directa e indirecta en la elaboración de cofias para prótesis implanto-soportadas. Para la técnica directa, las cofias se elaboraron sobre los pilares originales de los implantes, trasladándolos a un modelo de yeso; y para la indirecta, se realizaron sobre los modelos en yeso de los mismos; cabe resaltar que se la técnica indirecta se realizó dos veces una con supervisión docente y otra sin la misma. Cinco protesistas evaluaron con lupa la calidad de la adaptación marginal de cada cofia; utilizaron estos criterios de medición: cero para mala adaptación, uno para regular y dos para buena. Para las cofias confeccionadas en las que se utilizó la técnica indirecta, sin supervisión la media en cuanto a la calidad de la adaptación fue de 0,18; y con supervisi6n de 1.57; para la técnica directa fue de 1.60. Las técnicas de impresión directa e indirecta supervisada, con 1% de error, no presentaron diferencia estadística significativa, no así la técnica indirecta sin supervisión; por lo que para inexpertos se recomienda la utilización de la técnica directa.

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