71 research outputs found
Antarctic micrometeorites collected at the Dome Fuji Station
Antarctic micrometeorites (AMMs) were found among the precipitated fine particles recovered from a water tank in the Dome Fuji Station. These AMMs had been contained in the recent fallen snow around the station. Initial processing of the precipitated particles revealed that they were dominated by natural and artificial terrestrial materials, thus a series of processes were developed to separate AMMs from terrestrial particles. The recovery rate of AMMs by the processes was approximately 45% in weight, which was determined from a weight ratio of recovered/accreted AMMs. The micro-morphology and major-element concentration of the recovered AMMs were characterized. They appear to have been heated upon atmospheric entry to varying temperatures and can be classified into two major types based on the degree of heating : (1) fine-grained, irregular-shaped, partial-melted micrometeorites with chondritic composition, and (2) total-melted spherical micrometeorites with chondritic composition except for volatile elements. A digital catalog for the AMMs identified in this study was established on the web site [URL : http : //dust. cc. gakushuin. ac. jp/], in which optical characteristics, high-resolution images, and chemical compositions of individual AMMs are presented. The AMMs listed in the catalog are the first Japanese collection of extraterrestrial dust. The criterion and techniques developed for the selection and initial analysis of AMMs are applicable for the dust samples that are being collected by the 39th Japanese Antarctic Research Expedition team
CARACTERÍSTICAS MICROBIOLÓGICAS DE CARNE DE SIRI BENEFICIADA EM ANTONINA (PR) ANTES E APÓS A ADOÇÃO DE MEDIDAS DE BOAS PRÁTICAS
A carne de siri produzida em Antonina (PR) tradicionalmente é beneficiada e comercializada informalmente, em condiçõesmuitas vezes precárias. Na unidade de beneficiamento de pescado Serramar buscou-se a implantação de um modelo de produçãoindustrial. A adoção das boas práticas de fabricação é necessária para garantir a qualidade e segurança dos alimentos. O objetivo do trabalho foi verificar o efeito da adoção de medidas de boas práticas sobre a qualidade microbiológica da carne de siri beneficiada. Como instrumento de avaliação utilizou-se análise microbiológica da água de abastecimento e da carne de siri beneficiada na unidade. As amostras de carne de siri foram distribuídas em quatro grupos: grupo I – antes das alterações na higienização dos objetos e utensílios e mãos, tempo de exposição da carne de siri à temperatura ambiente e uso de luva; grupo II após adoção de medidas de boas práticas de fabricação referentes a higienização dos objetos, utensílios e mãos; grupo III após adoção das medidas de higienização, juntamente com a diminuição do tempo de exposição da carne de siri à temperatura ambiente e grupo IV posteriormente à adoção de medidas de higienização, diminuição do tempo de exposição e utilização de luva. A água de abastecimento não apresentou crescimentomicrobiológico. A análise microbiológica da carne de siri apresentou os seguintes resultados: contaminação por mesófilos e número mais provável (NMP) de coliformes totais mais alta no grupo I e decrescente à medida que foram adotadas as boas práticas. O NMP de coliformes termotolerantes foram altos no grupo I, com decréscimo nos grupos subseqüentes, havendo crescimento não esperado no grupo 4. Esse crescimento pode estar relacionado com contaminações da água do mar e cozimento inadequado. Em todas as amostras foi negativa a pesquisa de Salmonela sp. A pesquisa de Staphylococcus aureus apresentou-se em desacordo com a legislação nos 3 primeiros grupos e dentro do limite no grupo 4. Para o beneficiamento do siri a adoção de procedimentos de higienização e diminuição do tempo de exposição são insuficientes para prevenir o crescimentos S. aureus, sendo necessário o uso de luvas. Os resultados apresentados reforçam a necessidade da adoção de medidas de treinamento, capacitação pessoal e monitoramento da qualidade da água do mar e adequação de condições higiênico-sanitárias.The crab meat that is produced in Antonina (PR) is traditionally processed and commercialized informally under conditions that are many times precarious. With the Serramar Processing Unit a new model of industrial processing is sought. The adoption of of good manufacturing practices is made necessary to assure quality and safety of the foods. The main goal of this work is to assess thequality of the product by microbiologic analyses, considering the adoption of measures of good manufacturing practices. The microbiologic analysis of the supplied water and the crabmeat processed in the unit was used as an assessing tool. The crab meat samples were distributed in four groups: group I – before the alteration made in the hygiene process of the objects, tools and hands, exposure time of the crab meat to room temperature and the use of gloves; group II – after the adoption of good manufacturing practices for the hygiene process of objects, tools and hands; group III – after the adoption of the hygiene process together with the diminishing of the crab meat exposure time to room temperature and group IV – after the adoption of hygiene measures, diminishing of exposure time and the use of gloves. The supplied water did not present any microbiological growth. The crab meat presented the following results after the analyses:contamination by mesophylic and high total coliform MPN (most probable number), higher in group I and then going down as goodpractice measures were being adopted. The thermal-tolerant coliform MPN were high in group I, diminishing in the following groups showing an unexpected growth in the group IV. Such growth could be related to seawater contamination and inappropriate cooking. In all samples the presence of Salmonela sp was negative. The search for Staphylococus aureus showed itself in disagreement with the current regulations in the first three groups and within regulation limits in the group IV. For the processing of the crab meat the adoption of hygiene procedures and the diminishing of exposure time had showed themselves insufficient to prevent the growth of S. aureus. The use of gloves is made necessary. The results presented reinforce the need for the adoption of good manufacturing practices. There is a need for training and staff’s professional upgrading as well as the monitoring of seawater quality and appropriate sanitary-hygienicconditions. Such measures should be included in the good manufacturing practices manual
ラットのカルシウム吸収に及ぼすL型発酵乳酸カルシウムの影響
We investigated the effect of fermentation calcium L-lactate on the absorption of calcium in rats. Calcium carbonate was used as a source of calcium of control diet and fermentation calcium L-lactate was used as a source of calcium of test diet. Five-week-old rats were divided into two groups, one group was fed a control diet and another group was fed a test diet for 3 weeks. Both diets contained the same amounts of calcium (0.52%), phosphorus (0.40%) and magnesium (0.05%). Calcium absorption ratio, calcium retention ratio and the concentration of femur calcium of rats fed a test diets did not differ from a control diet group. The amount of femur calcium of rats fed a test diet was slightly higher than those of rats fed a control diet. These results suggest that the ingestion of fermentation calcium L-lactate was imagined to be valid for bony health
Cell-quintupling: Structural phase transition in a molecular crystal, bis(trans-4–butylcyclohexyl)methanol
A structural phase transition at 151.6 K of the title compound [bis(trans-4–butylcyclohexyl)methanol] is examined by X-ray diffraction crystallography, Fourier-transform infrared spectroscopy, and adiabatic calorimetry. A general consideration on possible superstructures indicates that a single modulation wave is sufficient to drive this cell-quintupling transition. The entropy of transition determined calorimetrically indicates that two conformations are dominant in the room-temperature phase in contrast to the fivefold disorder expected from the structure of the low-temperature phase
A prospective compound screening contest identified broader inhibitors for Sirtuin 1
Potential inhibitors of a target biomolecule, NAD-dependent deacetylase Sirtuin 1, were identified by a contest-based approach, in which participants were asked to propose a prioritized list of 400 compounds from a designated compound library containing 2.5 million compounds using in silico methods and scoring. Our aim was to identify target enzyme inhibitors and to benchmark computer-aided drug discovery methods under the same experimental conditions. Collecting compound lists derived from various methods is advantageous for aggregating compounds with structurally diversified properties compared with the use of a single method. The inhibitory action on Sirtuin 1 of approximately half of the proposed compounds was experimentally accessed. Ultimately, seven structurally diverse compounds were identified
Precocious Metamorphosis in the Juvenile Hormone–Deficient Mutant of the Silkworm, Bombyx mori
Insect molting and metamorphosis are intricately governed by two hormones, ecdysteroids and juvenile hormones (JHs). JHs prevent precocious metamorphosis and allow the larva to undergo multiple rounds of molting until it attains the proper size for metamorphosis. In the silkworm, Bombyx mori, several “moltinism” mutations have been identified that exhibit variations in the number of larval molts; however, none of them have been characterized molecularly. Here we report the identification and characterization of the gene responsible for the dimolting (mod) mutant that undergoes precocious metamorphosis with fewer larval–larval molts. We show that the mod mutation results in complete loss of JHs in the larval hemolymph and that the mutant phenotype can be rescued by topical application of a JH analog. We performed positional cloning of mod and found a null mutation in the cytochrome P450 gene CYP15C1 in the mod allele. We also demonstrated that CYP15C1 is specifically expressed in the corpus allatum, an endocrine organ that synthesizes and secretes JHs. Furthermore, a biochemical experiment showed that CYP15C1 epoxidizes farnesoic acid to JH acid in a highly stereospecific manner. Precocious metamorphosis of mod larvae was rescued when the wild-type allele of CYP15C1 was expressed in transgenic mod larvae using the GAL4/UAS system. Our data therefore reveal that CYP15C1 is the gene responsible for the mod mutation and is essential for JH biosynthesis. Remarkably, precocious larval–pupal transition in mod larvae does not occur in the first or second instar, suggesting that authentic epoxidized JHs are not essential in very young larvae of B. mori. Our identification of a JH–deficient mutant in this model insect will lead to a greater understanding of the molecular basis of the hormonal control of development and metamorphosis
Extracellular Vesicles in Bone Metastasis: Key Players in the Tumor Microenvironment and Promising Therapeutic Targets
Extracellular vesicles (EVs) are lipid membranous vesicles that are released from every type of cell. It has become clear that EVs are involved in a variety of biological phenomena, including cancer progression, and play critical roles in intracellular communication through the horizontal transfer of cellular cargoes such as proteins, DNA fragments, RNAs including mRNA and non-coding RNAs (microRNA, piRNA, and long non-coding RNA) and lipids. The most common cause of death associated with cancer is metastasis. Recent investigations have revealed that EVs are deeply associated with metastasis. Bone is a preferred site of metastasis, and bone metastasis is generally incurable and dramatically affects patient quality of life. Bone metastasis can cause devastating complications, including hypercalcemia, pathological fractures, spinal compression, and bone pain, which result in a poor prognosis. Although the mechanisms underlying bone metastasis have yet to be fully elucidated, increasing evidence suggests that EVs in the bone microenvironment significantly contribute to cancer progression and cancer bone tropism. Emerging evidence on EV functions in bone metastasis will facilitate the discovery of novel treatments. In this review, we will discuss the remarkable effects of EVs, especially on the tumor microenvironment in bone
Extracellular vesicles as a promising biomarker resource in liquid biopsy for cancer
Liquid biopsy is a minimally invasive biopsy method that uses molecules in body fluids as biomarkers, and it has attracted attention as a new cancer therapy tool. Liquid biopsy has considerable clinical application potential, such as in early diagnosis, pathological condition monitoring, and tailored treatment development based on cancer biology and the predicted treatment response of individual patients. Extracellular vesicles (EVs) are lipid membranous vesicles released from almost all cell types, and they represent a novel liquid biopsy resource. EVs carry complex molecular cargoes, such as proteins, RNAs [e.g., mRNA and noncoding RNAs (microRNA, transfer RNA, circular RNA and long noncoding RNA)], and DNA fragments; these cargoes are delivered to recipient cells and serve as a cell-to-cell communication system. The molecular contents of EVs largely reflect the cell of origin and thus show cell-type specificity. In particular, cancer-derived EVs contain cancer-specific molecules expressed in parental cancer cells. Therefore, analysis of cancer-derived EVs might indicate the presence and nature of cancer. High-speed analytical technologies, such as mass spectrometry and high-throughput sequencing, have generated large data sets for EV cargoes that can be used to identify many candidate EV-associated biomarkers. Here, we will discuss the challenges and prospects of EV-based liquid biopsy compared to other biological resources (e.g., circulating tumor cells and cell-free DNA) and summarize the novel studies that have identified the remarkable potential of EVs as a cancer biomarker
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