754 research outputs found

    Developing a framework for evaluating robotic care devices in the introduction phase

    Get PDF

    Utilización de desperdicios de camarón para recuperación de quitina, proteínas y pigmentos por vía microbiana

    Get PDF
    La fermentación láctica ha sido utilizada desde tiempos inmemoriales para aumentar la vida de anaquel de los alimentos, debido principalmente a la producción de ácidos orgánicos y compuestos con actividad antimicrobiana. En la presente tesis se estudió el uso de la fermentación láctica del desecho de camarón para la recuperación de productos de alto valor agregado, tales como quitina, pigmentos y proteasas. En una primera etapa se establecieron las condiciones de la fermentación mediante la selección del iniciador, probando dos cultivos comerciales de Christian Hansen: Floracarn SL (Lactobacillus pentosus y Staphylococcus carnosus) y LP- 1 (Lactobacillzrs pentoszts), así como cepas aisladas de camarones tropicales identificadas como Lactobacillus casei (A3) y Lactobacillus sp. (B2). La cepa B2 y Lactobacillus pentosus produjeron concentraciones más altas de ácido láctico, aunque en las fermentaciones con Lb. pentoms se detectaron bajas concentraciones de ácido acético, de ahí que la cepa B2 fuera elegida para la determinación de las concentraciones de la fbente de carbono (glucosa) y nivel de inoculación. Las concentraciones de glucosa e inóculo con las que se obtuvieron mejores resultados heron 10% (p/p base húmeda) y 5% (v/p base húmeda), respectivamente. Para la elección de las condiciones antes mencionadas e realizaron análisis estadístico de varianza así como superficies de respuesta. El uso de iniciador y la concentración inicial de glucosa heron factores determinantes en la fermentación láctica de desechos de camarón. En este sentido, altas concentraciones de glucosa e iniciador redujeron el tiempo de fermentación, e incrementaron la concentración del ácid0 láctico producido. La inoculación modificó el patrón fermentativo de hetero a homoláctico La microflora mostró una reducción inicial de enterobacterias, sin embargo después de 8 horas la cuenta de coliformes aumentó, mientras que la de bacterias Iácticas fue constante durante todo el tiempo de fermentación y solo hacia el final del cultivo disminuyó. La segunda etapa consistió en el aislamiento de los productos: proteasas, quitina y pigmentos, a partir del ensilado obtenido después de 48 horas. Se separaron dos fracciones una sólida y otra líquida, las cuales heron de un 55 a 60% y de 40 a 45 YO del peso original en base húmeda, respectivamente. El sólido o sedimento consistió principalmente de quitina, proteína, pigmentos y minerales, en un 2 1.23, 21.73, 0.0123 y 8.21% (p/p base seca) respectivamente. La purificación parcial de las proteasas a partir del ensilado fie llevada a cabo mediante ultrafiltración y cromatografia de permeación en gel (GPC). La fracción soluble de la fermentación he filtrada y centrifigada, y el líquido liofilizado para su almacenamiento. Posteriormente el polvo fue resuspendido y ultrafiltrado, su concentración y fraccionamiento fueron hechos probando diferentes membranas de 300, 50, 10 y 2 kDa. Las concentraciones de proteína y actividad proteolítica en caseína pH 7 y hemoglobina pH 2, heron determinadas en el permeado y retenido de cada ultrafiltración realizada, observándose que había una mayor concentración de proteínas con actividad utilizando membranas de 2 y 10 ma, no encontrándose diferencias significativas entre éstas. Sin embargo con la membraria de 2 el proceso era muy lento, por lo que se eligió el retenido obtenido con la de 10 kDa. Las fracciones de la ultrafiltración mostraron actividad en condiciones ácidas y alcalinas. El peso molecular de las fracciones con actividad fie determinado mediante (3% correspondiendo a 13, 26 y 56 kDa; la actividad específica he mayor a pH neutro que a ácido. El retenido que fie la fracción que presentó mayor actividad he aplicada en una etapa subsecuente para la desproteinización de quitina. Por vía fermentativa se removió un 75.7 YO de proteína y 65.80 YO de calcio de la quitina cruda (sedimento). Posteriofmente, se ralizaron tratamientos químicos para llevar a cabo despigmentación, desmineralización y desproteinización, para este último tratamiento se probaron proteasas comerciales y proteasas aisladas del camarón (retenido). Para la desproteinización enzimática se procedió a determinar el tiempo de reacción con tripsina bovina comercial durante 96 horas, encontrándose un aumento en la proteína soluble dukante las primeras 48 horas, y después de ese tiempo la concentración de proteína soluble se mantuvo estable. Por lo que se fijó un tiempo de 48 horas para estudios con las otras enzimas, proteasas de camarón, mezcla de enzimas: Savinasa, Neutrasa, Alcalasa y Esperasa (Novo, Copenhague, Dinamarca). Asimismo para comparar fueron obtenidas quitinas a partir del desecho sin fermentar y se analizaron productos comerciales. Análisis elemental y espectroscopia de infrarrojo por transformada de Fourier heron empleadas para caracterizar las quitinas obtenidas. Los resultados indicaron que los productos de la fermentación Iáctica heron similares a los producidos por métodos tradicionales.Ensilation of prawn waste allows the recovery of added value products such as chitin, pigments and proteins, which could be used for animal feed, and other applications. Ensilation is defined as a conservation process in which acids, added or produced, inhibit the growth of pathogen microorganisms. In a fermented silage acid is produced in sit21 by lactic acid bacteria, using carbohydrate sources. In this study the fermentation conditions and selection of microorganism were determined based on acid production, glucose concentration as carbohydrate source, and inoculum level. Afterwards the fermentation pattern was determined. From the various lactic acid bacteria tested, Lactobacillus yerltoszts and Lactobacillus sp. (B2) were the best acid-producing microorganisms. However small quantities of acetic acid were detected in samples inoculated with Lactobacillus pentosns, therefore B2 was chosen for the determination of glucose and inoculum levels; the best results were obtained at 10% (w/w w.b.1 and 5% (viw w.b.), respectively. The use of starters and the initial glucose concentration were critical factors in prawn head fermentation. High initial glucose and starter concentrations reduced fermentation time and increased the amount of lactic acid produced. Inoculation modified the fermentation from heterofermentative to homofermentative. There was an initial reduction of enterobacteria, but after 8 hours of fermentation coliform counts increased whereas lactic acid bacteria counts were constant during most of the fermentation time, and decreased at the end. The above described conditions produced a stable silage, with two fractions: solid and liquid The next stage was the recovery of products: partial purification of proteases was done from the liquid by means of ultrafiltration and gel permeation chromatography. Molecular weight proteases ranged at 13, 26 and 56 kDa, specific activity was higher at pH 7 than 2 Finally the chitin and pigments were extracted from the solid, 21 and 0.012 YO (wiw wet basis): respectively. Chitin was isolated from the silage solid after demineralisation with hydrochloric acid and deproteination with alkali. Enzymatic deproteination was carried out using commercial proteases (Alcalase, Pronase, Savlnase and Esperase) and proteases from the fermented prawn waste. Chitin FTIR spectra and elemental analysis were comparable with commercial products. K-qwords: prcrwn wastes, lactic acid fermentation, chitin, Lactobacillw, proteases, pigmerlts, protein silage

    在宅認知症高齢者を介護する家族介護者の介護経験を通した気付き

    Get PDF
    在宅認知症高齢者の家族介護者は,介護するうえでさまざまな経験をしながら介護を継続している.その現場で起こっている現象に着目した報告は,未だ嚆矢の段階といえる.そこで,認知症高齢者を抱える家族の介護経験を通した気付きを明らかにするために,質的因子探索的に分析を行った.「認知症の人と家族の会A 県支部」会員の家族介護者70人から半構成的質問紙に対して回答が得られた.その結果,【制度の活用と課題】【患者の交流の場拡充の必要性】【認知症の啓蒙活動充実の必要性】【認知症や介護制度に対する自分の知識不足】【金銭的負担の大きさ】【周囲の協力の必要性】の6カテゴリーを抽出した.家族介護者の気付きを分析し考察した結果,満足して介護制度を活用している半面,制度の課題についても,気付きを持っていた.また,自己の知識不足も含めて社会の理解の重要性も必要であると感じていた.さらに,認知症の本人の交流の場などの充実が重要であるとも気付いていた.やはり,介護は経済的にも負担が大きいが,周囲に理解してもらい協力を得ることが大切であるということに気付いていた.As indicated by the referring to family care givers as“second patients”, family members are known to be providing nursing care while bearing various latent burdens. However, reports focusing on events that occur in the care setting are still only in the initial stages. Therefore, a qualitative factor exploratory analysis was conducted by focusing on findings based on the experiences of caregivers in order to identify thoughts and impressions obtained through the experience of providing care of family members caring for elderly dementia patients. The analysis was targeted at 70 members of the“A Prefecture Branch of a Dementia Patient and Family Member Group”from whom replies were obtained to a semi-structured questionnaire. As a result, 6 categories were extracted from the replies, consisting of“use of programs”,“enhancement of opportunities for exchanges among patients”, “substantiation of dementia educational activities”,“regrets over lack of knowledge”,“monetary burden” and“cooperation of others”. As a result of analyzing and discussing the thoughts of family members from the viewpoint of findings obtained through the providing of care, it was found that the thoughts of family members regarding dementia programs are complex, and consist of numerous thoughts, including those indicating satisfaction as well as calling for improvements. However, the respondents also felt a need to place importance on social understanding, including an awareness of their own lack of knowledge. On the other hand, the respondents were also aware of the importance of providing greater opportunities for exchanges among patients themselves. In addition, although the providing of care is also associated with a considerable financial burden, it was also found that obtaining the understanding and cooperation of others in the community is also important

    Prospect of cytologic diagnosis for malignant melanoma in the maxillary sinus

    Get PDF
    Two cases of malignant melanoma arising in the maxillary sinus are reported. Cytological examination of the solution obtained by local washing through the sinus puncture identified numerous melanoma cells together with melanophages. The cases were then scheduled for well-planned, preoperative treatment. The cytological criteria for diagnosing malignant melanoma are outlined, and the cytological approach is stressed as a valuable diagnostic procedure for early detection of malignant tumors and surveillance of postoperative recurrence, especially in paranasal sinuses.</p

    nfi-1 affects behavior and life-span in C. elegans but is not essential for DNA replication or survival

    Get PDF
    BACKGROUND: The Nuclear Factor I (one) (NFI) family of transcription/replication factors plays essential roles in mammalian gene expression and development and in adenovirus DNA replication. Because of its role in viral DNA replication NFI has long been suspected to function in host DNA synthesis. Determining the requirement for NFI proteins in mammalian DNA replication is complicated by the presence of 4 NFI genes in mice and humans. Loss of individual NFI genes in mice cause defects in brain, lung and tooth development, but the presence of 4 homologous NFI genes raises the issue of redundant roles for NFI genes in DNA replication. No NFI genes are present in bacteria, fungi or plants. However single NFI genes are present in several simple animals including Drosophila and C. elegans, making it possible to test for a requirement for NFI in multicellular eukaryotic DNA replication and development. Here we assess the functions of the single nfi-1 gene in C. elegans. RESULTS: C. elegans NFI protein (CeNFI) binds specifically to the same NFI-binding site recognized by vertebrate NFIs. nfi-1 encodes alternatively-spliced, maternally-inherited transcripts that are expressed at the single cell stage, during embryogenesis, and in adult muscles, neurons and gut cells. Worms lacking nfi-1 survive but have defects in movement, pharyngeal pumping and egg-laying and have a reduced life-span. Expression of the muscle gene Ce titin is decreased in nfi-1 mutant worms. CONCLUSION: NFI gene function is not needed for survival in C. elegans and thus NFI is likely not essential for DNA replication in multi-cellular eukaryotes. The multiple defects in motility, egg-laying, pharyngeal pumping, and reduced lifespan indicate that NFI is important for these processes. Reduction in Ce titin expression could affect muscle function in multiple tissues. The phenotype of nfi-1 null worms indicates that NFI functions in multiple developmental and behavioral systems in C. elegans, likely regulating genes that function in motility, egg-laying, pharyngeal pumping and lifespan maintenance
    corecore