Effects of Liquid Medium Environment on Elastic Modulus of Breast Cancer Cells / 医用生物力学

Objective To study the effect of three kinds of commonly used liquid culture media for in vitro cell experiments on elastic modulus of breast cancer cells, so as to provide references for developing novel diagnosis and treatment approach of tumour based on mechanics principles. Methods The elastic modulus and adhesion force of breast cancer cells MCF7 to atomic force microscopy (AFM) probes in phosphate buffered solution(PBS), Dulbecco’s modified eagle media (DMEM) and DMEM+10% fetal bovine serum (FBS) were measured using AFM technology. Results The elastic moduli of breast cancer cells in PBS, DMEM and DMEM+10% FBS were 2.59, 2.11 and 1.59 kPa, respectively. The cell adhesion forces in the above three kinds of liquid medium environment were 63.81, 66.09 and 121.97 pN, respectively. Cell adhesion force in DMEM+10%FBS was significantly different from that of the other two kinds of liquid media. Conclusions There are significant differences in elastic modulus of breast cancer cells in three kinds of liquid media. The difference between DMEM and DMEM+10%FBS might be caused by the different adhesion force caused by serum proteins in the media, and the difference between DMEM and PBS might be attributed to the difference in pH of the media.

Comparación del sistema BacT/ALERT® 3D con los métodos de cultivo Lowenstein-Jensen y Ogawa-Kudoh para el aislamiento de micobacterias / Comparison of BacT/ALERT 3D® system with the culture methods of Lowenstein-Jensen and Ogawa-Kudoh, for the isolation of mycobacteria

La tuberculosis es una enfermedad causada por bacterias pertenecientes al Complejo Mycobacterium tuberculosis. El diagnóstico se dificulta por su sintomatología inespecífica y los métodos bacteriológicos que ofrecen resultados tardíos. El objetivo del presente estudio fue comparar el desempeño del sistema automatizado BacT/ALERT® 3D con los métodos convencionales de cultivo en medio Lowenstein-Jensen (L-J) y Ogawa-Kudoh (O-K) para el aislamiento de micobacterias. Se procesaron 266 muestras provenientes de pacientes con sospecha de tuberculosis entre mayo y octubre de 2013. Se aislaron 63 bacilos acido-resistentes: 46 M. tuberculosis y 17 micobacterias no tuberculosas (MNT). Al comparar los tres métodos, se observó que todos presentaron desempeño similar en el aislamiento de M. tuberculosis. Las tasas de recuperación obtenidas no mostraron diferencia estadísticamente significativa (p>0,05) sin embargo, con BacT/ALERT® 3D se aislaron mayor número de MNT, con diferencia significativa respecto al L-J (p<0,05). El tiempo de detección promedio de M. tuberculosis fue de 11 días por BacT/ALERT® 3D, 20 días en L-J y 23 días en O-K. La contaminación cruzada, fue de 0,38%. Se concluyó que BacT/ALERT® 3D es una excelente herramienta para el aislamiento de M. tuberculosis, mejora la recuperación de las MNT y reduce significativamente el tiempo de diagnóstico, lo que permitiría un tratamiento oportuno, con mayor probabilidad de sobrevida del paciente.

Tuberculosis is a disease caused by species of the Mycobacterium tuberculosis complex. The diagnosis is difficult due to nonspecific symptoms and late results of bacteriological culture methods. The aim of this study was to compare the efficiency of the BacT/ALERT® 3D automated system with conventional methods of culture on Lowenstein-Jensen (L-J) and Ogawa-Kudoh (O-K). A total of 266 specimens from patients with clinical suspected tuberculosis were studied from May to October 2013. We recovered, 63 acid fast bacilli isolates: 46 identified as M. tuberculosis and 17 as nontuberculous mycobacteria (NTM). The three methods had a similar performance for isolation of M. tuberculosis; recovery rates obtained showed no statistically significant difference (p> 0.05). However, with the BacT/ALERT® 3D system, a larger number of MNT were isolated, with significant statistic difference for L-J (p <0.05). The average detection time for M. tuberculosis was 11 days with the BacT/ALERT® 3D system, with significant statistic difference for LJ (20.4 days) and O-K (23.2 days). Additionally, cross-contamination was determined as 0.38%. The study results showed that the BacT/ALERT® 3D system is an excellent tool for isolation of M. tuberculosis and it improves the recovery of NTM. Also, the time of diagnosis is significantly reduced, leading to earlier treatment that could improve patient recovery.

Cattleya walkeriana growth in different micropropagation systems / Crescimento de Cattleya walkeriana em diferentes sistemas de micropropagação

The aim of the present research was to verify the in vitro growth of orchids in different systems of micropropagation, being cultivated in a bioreactor, with natural ventilation and conventional systems. Cattleya walkeriana plants were obtained from the germination of seeds in culture medium. After 8 months, seedlings with 1 cm of length were placed in a culture vessel according to the treatments, which counted with two micropropagation systems (conventional and natural ventilation) in three media of culture (liquid, solid with 5 or 6g L-1 of agar). Two additional treatments in bioreactor of temporary and continuous immersion were performed. The design was entirely randomized (ERD), consisting of a 2x3 factorial with two additional treatments, totaling 8 treatments with three repetitions. The temporary immersion bioreactor promoted a bigger growth of the aerial part and of the root system, bigger accumulation of dry mass and better control of water loss by the plants. The temporary immersion bioreactor is the best micropropagation system for the C. walkeriana growth in vitro.

O objetivo do presente trabalho foi verificar o crescimento in vitro de orquídeas em diferentes sistemas de micropropagação, sendo cultivado em biorreator, sistema de ventilação natural e convencional. Plantas de Cattleya walkeriana foram obtidas a partir da germinação de sementes em meio de cultura. Após o a germinação, as plantas foram uniformizadas com aproximadamente 1,0cm de comprimento e inoculadas nos diferentes tratamentos. Os tratamentos contaram dois sistema de micropropagação (convencional e ventilação natural) e três meios de cultura (líquido, sólido com 5 e 6g L-1 de ágar). Foram realizados dois tratamentos adicionais em biorreator de imersão temporária e contínua. O delineamento foi o inteiramente casualizado, consistindo de um fatorial 2x3 com dois tratamentos adicionais, totalizando oito tratamentos com três repetições. O biorreator de imersão temporária promoveu o maior crescimento da parte aérea e do sistema radicular, maior acúmulo de massa seca e melhor controle da perda de água das plantas. O biorreator de imersão temporária é o melhor sistema de micropropagação para o crescimento in vitro de C. walkeriana.

Volume do frasco e consistência do meio de cultura na multiplicação in vitro da bananeira 'Maçã' / Flask size and growth medium consistence in the in vitro multiplication of 'Maçã' banana tree

A propagação in vitro da bananeira possibilita produzir, em larga escala, mudas livres de doenças em curto espaço de tempo. Para otimizar o processo de micropropagação, pode-se modificar a metodologia de produção das mudas, levando-se em conta também a manutenção da qualidade. O objetivo deste trabalho foi avaliar a influência do volume do frasco e da consistência do meio de cultura na taxa de multiplicação e no desenvolvimento de mudas de bananeira 'Maçã', propagadas in vitro. A partir de ápices caulinares, foram realizados quatro subcultivos (S2, S3, S4 e S5) em meio MS modificado com metade da concentração dos macronutrientes, acrescido de 30g L-1 de sacarose e 2,5mg L-1 de BAP (6 benzilaminopurina), em tratamento fatorial 2x2: dois tipos de meio de cultivo (semissólido por adição de 1,6g L-1 de Phytagel™ e líquido estacionário) e frascos de dois volumes (250 e 500mL). As plântulas foram induzidas ao enraizamento in vitro e aclimatizadas em estufas, em bandejas de 72 células, e posteriormente cultivadas em sacos de polipropileno de 17x18cm. O cultivo meio líquido em frasco de 500mL pode ser adotado com sucesso para multiplicação de mudas de banana 'Maçã', tendo sido observada maior taxa de multiplicação (25,27 brotos/frasco), melhor adaptação no início da aclimatização e desempenho similar aos demais tratamentos após 60 dias de cultivo em sacos de polipropileno.

The in vitro propagation of the banana is accomplished to produce large quantities of seedlings free from diseases. Micropropagation process can be optimized changing the method, but also considering plantlet quality. The objective of this work was to evaluate the influence of the flask size and of the growth medium consistence on the multiplication rate and on the initial plantlet development of in vitro propagated 'Maçã' banana tree. Starting from stem apexes, four subcultures were accomplished (S2, S3, S4 and S5) in MS medium modified with the half of the concentration of the macronutrients, added of 30g L-1 of sucrose, 2.5mg L-1 of BAP (6-benzylaminopurine) in factorial design 2x2: two types of growth media (semi solid by addition of 1.6g L-1 Phytagel™ and stationary liquid), and two flask sizes (250 and 500mL). Plantlets were induced in vitro rooting and acclimatization in greenhouse using trays with 72 cells and later grown in 17x18cm polypropylene bags. Cultivation in liquid medium bottle of 500mL can be successfully adopted for propagation of 'Maçã' banana plantlets because it had larger multiplication rate (25.27), better adaptation in the initial stage of acclimatization and similar performance to the other treatments after 60 days of cultivation in the bags.

Cultural Characteristics of Shimizuomyces paradoxus Collected from Korea

This study investigated the cultural characteristics of Shimizuomyces paradoxus in different nutritional and environmental conditions. The highest mycelial growth was observed in Schizophyllum (mushroom) genetics complete medium plus yeast extract agar medium, and the optimal temperature and pH were 25degrees C and pH 8.0, respectively. The optimal carbon and nitrogen sources were 1% dextrose and 1% peptone in agar. However, in liquid culture the highest dry mycelium weight was found for the potato dextrose agar and potato sucrose agar broths. The optimum inoculum size was five mycelial discs (5 mm) per 100 mL of broth, and the optimum liquid culture period was 25 days. This is the first ever report of S. paradoxus cultural characteristics.

Evaluation of the biodegradation of different types of lubricant oils in liquid medium

The aim of this work was to study the biodegradation of different types of automotive lubricant oils adapted to the aqueous medium using a base inoculum and an aqueous inoculum. Four treatments were carried out in two consecutive and similar experiments: T1 (control); T2 (half-synthetic oil); T3 (mineral oil); T4 (used oil). The results showed the following decreasing order of CO2 production in the Bartha and Pramer respirometers: T4 > T2 > T3 > T1. Thus, the used lubricant oil showed with highest biodegradability, followed by the half-synthetic one and the mineral oil. It was also observed that the mineral lubricant presented a longer period of adaptation compared to the half-synthetic one.

Avaliação da Biodegradação de Diferentes Tipos de Óleo Lubrificante em Meio Aquoso pela Norma Técnica L6.350 (CETESB, 1990), utiliza-se o processo respirométrico de Bartha e Pramer para acompanhar a biodegradação de diferentes tipos de óleo lubrificante automotivo adaptado ao meio aquoso. Para realização do experimento foram preparados um inóculo base e, posteriormente, um inóculo aquoso. Quatro tratamentos foram realizados em dois experimentos consecutivos: T1 (controle); T2 (óleo semi-sintético); T3 (óleo mineral); T4 (óleo usado). Dentre os resultados, obteve-se a seguinte ordem decrescente na produção de CO2 nos respirômetros: T4 > T2 > T3 > T1. Assim, o óleo lubrificante usado surgiu com maior biodegradabilidade, seguido do semisintético e do óleo mineral. Observou-se também que o lubrificante mineral apresentou maior período de adaptação comparado ao semisintético.

Production of Blastospore of Entomopathogenic Beauveria bassiana in a Submerged Batch Culture

The principal objective of this study was to determine the optimal liquid culture conditions in shake flasks for maximal sporulation of Beauveria bassiana. The optimal initial pH for the spore production of B. bassiana using Potato Dextrose Broth was 5.2. The screening in shake flasks of carbon and nitrogen sources resulted in the identification of an optimal medium based on 3% sucrose and 1% casamino acid, with a C : N ratio of 22 : 4. Using this medium, a production level of 5.65 x 107 spores per ml was obtained after 5 days of culture. Using 3% corn meal, 2% corn steep powder, and 2% rice bran, the maximum spore concentration of 8.54 x 108/ml was achieved 8 days after inoculation at 25degrees C in a rotary shaking incubator operated at 200 rpm. This represents a yield gain of approximately 2.89 times that of pre-optimization.