983 resultados para BIOLOGICAL SAMPLES


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Since 1966 especially recent decade, Caspian trout (Salmo trutta caspius Kessler, 1877) considered as a strategic endemic species for Caspian Sea fisheries resources also coldwater aquaculture in Iran. Nowadays habitat condition effects on this subspecies during life stages, artificial breeding and incubation period noticed by research and execution sessions of fisheries in Iran. Incubation duration of Caspian trout from artificial fertilization followed by green egg and eyed egg, hatching and yolk sac absorption identified as most sensitive stages for fish and any pollution, stress and deviation by natural life conditions of embryo up to larvae could provide possible mortalities and observable or hidden alterations. Among all vital factors for Caspian trout welfare even in conservation plans and stocks rehabilitation programs or recent attempts for domestication of this fish for introduction to cold water aquaculture industry, water temperature as the most important physical factor which might conserve or induce stress to rearing environment condition is not considered yet. In hatcheries activities, the temperature for incubation and rearing Caspian trout eggs is determining by available water temperature and wide range of temperatures in governmental or private farms is using depend on the water resources availability. Also global climate change consideration and increase temperature trend accompany with group of physical and chemical factors provided by fish farm discharges and other source points entered to the migration pathway of Caspian trout in spawning season were not investigated before. Natural spawning migration pathway is upstream of Caspian tout south and south west rivers especially in Cheshmehkileh upstream in Tonekabon, Iran directed this research focus on the mentioned location. For simulation of natural spawning bed for Caspian trout, water supplied from the upstream of Daryasar branch as headwater of Cheshmehkileh River which provided REDD water condition for in vitro incubation. Green eggs treatments of wild and F1 cultured brooders both 3+ were incubated. Incubation implemented in dark, constant temperature (4, 8, 12 degree centigrade) and DO–pH–temperature digital monitoring in 3 recycling incubators ended to yolk sac absorption and entering larval stage. Hatching success, possible genome alterations by HSP70 gene expression and comet assay implemented as diagnostic tools in 3 life stages of eyed egg– Alevin and Larvae. Numbers and diameters of larvae white fiber muscles measured by histology experiment and Hematoxylin–eosine staining. Results stated significant effect of incubation temperature on hatching success, genome and white fiber muscles of wild and F1 samples. Hatching success measured as 31% and 38% for cultured and wild cold treatments, 79% and 91% for normal and 64% and 73% for warm cultured and wild treatments respectively. Considerable mortality occurred for cold treatment and 8 degree centigrade stated the best thermal condition in normal incubator according to hatching success in wild Caspian trout samples.

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Vaccinum myrtillus L. belongs to Ericaceae family, being commonly known for its sweet small fruits: the blueberries. Widely consumed in fresh, these fruits are also used in jams and marmalades due to their digestive and hypoglycemic properties and also due to the presence of several bioactive compounds [!]. Therefore, it has become a very appealing matrix in the development of functional products that, beyond their nutritional properties, will add a long-term beneficial physiological/health effect [2]. In the present work, three novel blueberry based products developed by RBR Foods Company (Portugal), were characterized in terms of their nutritional and chemical properties: carbohydrates, ash, proteins, fat and energetic value (following official methods of food analysis), fatty acids profile (by CG-FID), soluble sugars (by HPLCRI), organic acids (by HPLC-DAD) and tocopherols (by HPLC-fluorescence). The products result from a mixture of the fruits with rose petals (PI), marigold petals (P2) and apple and goji berries (P3). The blueberry fruits were used as control sample. The nutritional profile of the novel products was very similar to the control sample: the carbohydrates were the most abundant macronutrient, followed by proteins and total fat. Regarding sugars, fructose, glucose and sucrose were identified in all the samples. P 1 and P2 didn't show significant differences in comparison to the control, however, P3 revealed a lower concentration of sugars. In terms of fatty acids composition, all the studied samples presented higher contents in polyunsaturated fatty acids, especially due to the contribution of linoleic and alinolenic acids. The results of tocopherols revealed that the control sample only presented two isoforrns of tocopherols, a- and y-tocopherol, being the same observed in P3. However, P 1 revealed the presence of all the isoforrns of tocopherols, while P2 was lacking otocopherol; which is related with the contribution of rose and marigold petals, respectively. The a-tocopherol isoforrn was the most abundant in all the studied samples. Overall, this work contributed to the nutritional characterization of novel blueberry based products and is a part of a wider project that aims the detailed study of these products, namely their potential to be used as functional foods.

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La spectrométrie de masse mesure la masse des ions selon leur rapport masse sur charge. Cette technique est employée dans plusieurs domaines et peut analyser des mélanges complexes. L’imagerie par spectrométrie de masse (Imaging Mass Spectrometry en anglais, IMS), une branche de la spectrométrie de masse, permet l’analyse des ions sur une surface, tout en conservant l’organisation spatiale des ions détectés. Jusqu’à présent, les échantillons les plus étudiés en IMS sont des sections tissulaires végétales ou animales. Parmi les molécules couramment analysées par l’IMS, les lipides ont suscité beaucoup d'intérêt. Les lipides sont impliqués dans les maladies et le fonctionnement normal des cellules; ils forment la membrane cellulaire et ont plusieurs rôles, comme celui de réguler des événements cellulaires. Considérant l’implication des lipides dans la biologie et la capacité du MALDI IMS à les analyser, nous avons développé des stratégies analytiques pour la manipulation des échantillons et l’analyse de larges ensembles de données lipidiques. La dégradation des lipides est très importante dans l’industrie alimentaire. De la même façon, les lipides des sections tissulaires risquent de se dégrader. Leurs produits de dégradation peuvent donc introduire des artefacts dans l’analyse IMS ainsi que la perte d’espèces lipidiques pouvant nuire à la précision des mesures d’abondance. Puisque les lipides oxydés sont aussi des médiateurs importants dans le développement de plusieurs maladies, leur réelle préservation devient donc critique. Dans les études multi-institutionnelles où les échantillons sont souvent transportés d’un emplacement à l’autre, des protocoles adaptés et validés, et des mesures de dégradation sont nécessaires. Nos principaux résultats sont les suivants : un accroissement en fonction du temps des phospholipides oxydés et des lysophospholipides dans des conditions ambiantes, une diminution de la présence des lipides ayant des acides gras insaturés et un effet inhibitoire sur ses phénomènes de la conservation des sections au froid sous N2. A température et atmosphère ambiantes, les phospholipides sont oxydés sur une échelle de temps typique d’une préparation IMS normale (~30 minutes). Les phospholipides sont aussi décomposés en lysophospholipides sur une échelle de temps de plusieurs jours. La validation d’une méthode de manipulation d’échantillon est d’autant plus importante lorsqu’il s’agit d’analyser un plus grand nombre d’échantillons. L’athérosclérose est une maladie cardiovasculaire induite par l’accumulation de matériel cellulaire sur la paroi artérielle. Puisque l’athérosclérose est un phénomène en trois dimension (3D), l'IMS 3D en série devient donc utile, d'une part, car elle a la capacité à localiser les molécules sur la longueur totale d’une plaque athéromateuse et, d'autre part, car elle peut identifier des mécanismes moléculaires du développement ou de la rupture des plaques. l'IMS 3D en série fait face à certains défis spécifiques, dont beaucoup se rapportent simplement à la reconstruction en 3D et à l’interprétation de la reconstruction moléculaire en temps réel. En tenant compte de ces objectifs et en utilisant l’IMS des lipides pour l’étude des plaques d’athérosclérose d’une carotide humaine et d’un modèle murin d’athérosclérose, nous avons élaboré des méthodes «open-source» pour la reconstruction des données de l’IMS en 3D. Notre méthodologie fournit un moyen d’obtenir des visualisations de haute qualité et démontre une stratégie pour l’interprétation rapide des données de l’IMS 3D par la segmentation multivariée. L’analyse d’aortes d’un modèle murin a été le point de départ pour le développement des méthodes car ce sont des échantillons mieux contrôlés. En corrélant les données acquises en mode d’ionisation positive et négative, l’IMS en 3D a permis de démontrer une accumulation des phospholipides dans les sinus aortiques. De plus, l’IMS par AgLDI a mis en évidence une localisation différentielle des acides gras libres, du cholestérol, des esters du cholestérol et des triglycérides. La segmentation multivariée des signaux lipidiques suite à l’analyse par IMS d’une carotide humaine démontre une histologie moléculaire corrélée avec le degré de sténose de l’artère. Ces recherches aident à mieux comprendre la complexité biologique de l’athérosclérose et peuvent possiblement prédire le développement de certains cas cliniques. La métastase au foie du cancer colorectal (Colorectal cancer liver metastasis en anglais, CRCLM) est la maladie métastatique du cancer colorectal primaire, un des cancers le plus fréquent au monde. L’évaluation et le pronostic des tumeurs CRCLM sont effectués avec l’histopathologie avec une marge d’erreur. Nous avons utilisé l’IMS des lipides pour identifier les compartiments histologiques du CRCLM et extraire leurs signatures lipidiques. En exploitant ces signatures moléculaires, nous avons pu déterminer un score histopathologique quantitatif et objectif et qui corrèle avec le pronostic. De plus, par la dissection des signatures lipidiques, nous avons identifié des espèces lipidiques individuelles qui sont discriminants des différentes histologies du CRCLM et qui peuvent potentiellement être utilisées comme des biomarqueurs pour la détermination de la réponse à la thérapie. Plus spécifiquement, nous avons trouvé une série de plasmalogènes et sphingolipides qui permettent de distinguer deux différents types de nécrose (infarct-like necrosis et usual necrosis en anglais, ILN et UN, respectivement). L’ILN est associé avec la réponse aux traitements chimiothérapiques, alors que l’UN est associé au fonctionnement normal de la tumeur.

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Human scent, or the volatile organic compounds (VOCs) produced by an individual, has been recognized as a biometric measurement because of the distinct variations in both the presence and abundance of these VOCs between individuals. In forensic science, human scent has been used as a form of associative evidence by linking a suspect to a scene/object through the use of human scent discriminating canines. The scent most often collected and used with these specially trained canines is from the hands because a majority of the evidence collected is likely to have been handled by the suspect. However, the scents from other biological specimens, especially those that are likely to be present at scenes of violent crimes, have yet to be explored. Hair, fingernails and saliva are examples of these types of specimens. In this work, a headspace solid phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) technique was used for the identification of VOCs from hand odor, hair, fingernails and saliva. Sixty individuals were sampled and the profiles of the extracted VOCs were evaluated to assess whether they could be used for distinguishing individuals. Preliminary analysis of the biological specimens collected from an individual (intra-subject) showed that, though these materials have some VOCs in common, their overall chemical profile is different for each specimen type. Pair-wise comparisons, using Spearman Rank correlations, were made between the chemical profiles obtained from each subject, per a specimen type. Greater than 98.8% of the collected samples were distinguished from the subjects for all of the specimen types, demonstrating that these specimens can be used for distinguishing individuals. Additionally, field trials were performed to determine the utility of these specimens as scent sources for human scent discriminating canines. Three trials were conducted to evaluate hair, fingernails and saliva in comparison to hand odor, which was considered the standard source of human odor. It was revealed that canines perform similarly to these alternative human scent sources as they do to hand odor implying that, though there are differences in the chemical profiles released by these specimens, they can still be used for the discrimination of individuals by trained canines.

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The presence of inhibitory substances in biological forensic samples has, and continues to affect the quality of the data generated following DNA typing processes. Although the chemistries used during the procedures have been enhanced to mitigate the effects of these deleterious compounds, some challenges remain. Inhibitors can be components of the samples, the substrate where samples were deposited or chemical(s) associated to the DNA purification step. Therefore, a thorough understanding of the extraction processes and their ability to handle the various types of inhibitory substances can help define the best analytical processing for any given sample. A series of experiments were conducted to establish the inhibition tolerance of quantification and amplification kits using common inhibitory substances in order to determine if current laboratory practices are optimal for identifying potential problems associated with inhibition. DART mass spectrometry was used to determine the amount of inhibitor carryover after sample purification, its correlation to the initial inhibitor input in the sample and the overall effect in the results. Finally, a novel alternative at gathering investigative leads from samples that would otherwise be ineffective for DNA typing due to the large amounts of inhibitory substances and/or environmental degradation was tested. This included generating data associated with microbial peak signatures to identify locations of clandestine human graves. Results demonstrate that the current methods for assessing inhibition are not necessarily accurate, as samples that appear inhibited in the quantification process can yield full DNA profiles, while those that do not indicate inhibition may suffer from lowered amplification efficiency or PCR artifacts. The extraction methods tested were able to remove >90% of the inhibitors from all samples with the exception of phenol, which was present in variable amounts whenever the organic extraction approach was utilized. Although the results attained suggested that most inhibitors produce minimal effect on downstream applications, analysts should practice caution when selecting the best extraction method for particular samples, as casework DNA samples are often present in small quantities and can contain an overwhelming amount of inhibitory substances.^

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Eighteen Corynebacterium xerosis strains isolated from different animal clinical specimens were subjected to phenotypic and molecular genetic studies. On the basis of the results of the biochemical characterization, the strains were tentatively identified as C. xerosis. Phylogenetic analysis based on comparative analysis of the sequences of 16S rRNA and rpoB genes revealed that the 18 strains were highly related to C. xerosis, C. amycolatum, C. freneyi, and C. hansenii. There was a good concordance between 16S rRNA and partial rpoB gene sequencing results, although partial rpoB gene sequencing allowed better differentiation of C. xerosis. Alternatively, C. xerosis was also differentiated from C. freneyi and C. amycolatum by restriction fragment length polymorphism analysis of the 16S-23S rRNA gene intergenic spacer region. Phenotypic characterization indicated that besides acid production from D-turanose and 5-ketogluconate, 90% of the strains were able to reduce nitrate. The absence of the fatty acids C(14:0), C(15:0), C(16:1)omega 7c, and C(17:1)omega 8c can also facilitate the differentiation of C. xerosis from closely related species. The results of the present investigation demonstrated that for reliable identification of C. xerosis strains from clinical samples, a combination of phenotypic and molecular-biology-based identification techniques is necessary.

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Background. Glioblastoma (GBM) is the most common primary tumor of central nervous system and it has a poor prognosis. Standard first line treatment, which includes surgery followed by adjuvant radio-chemotherapy,produces only modest benefits to survival. The interest for immunotherapy in this field derives from the development of new drugs and effective therapies as immune-check points inhibitors, adoptive T-cell approaches or dendritic cell (DC) based vaccines or a combinations of these. GBM is described as a typical “immune-deserted” cancer exhibiting a number of systemic and environmental immunosuppressive factors. Considering the role of microenvironment, and above all the lower tumor load and depletion of immunosuppressive cells in GBM, our hypothesis is that DC vaccine may induce an immune response. Main aims and study design. The main aim of this project is to study the role of immune system in GBM, including identification of potential prognostic and predictive markers of outcome and response to dendritic cell vaccine. Firstly, we performed a retrospective analysis on blood samples. Then, we analyzed the immuno-component in tissues samples of enrolled patients; and compared that with blood results. Then, the last part of the project is based on a prospective clinical trial on patients enrolled in DC-based vaccination produced at IRST Cell Factory and actually used for patients with melanoma and other tumors. The enrollment is still ongoing. Expected results. The project will i) develop an immune-panel of prognostic and predictive markers to help clinicians to improve the therapeutic strategy for GBM patients; ii) provide preliminary results on the effectiveness of immunotherapy on GBM patients.

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To detect the presence of male DNA in vaginal samples collected from survivors of sexual violence and stored on filter paper. A pilot study was conducted to evaluate 10 vaginal samples spotted on sterile filter paper: 6 collected at random in April 2009 and 4 in October 2010. Time between sexual assault and sample collection was 4-48hours. After drying at room temperature, the samples were placed in a sterile envelope and stored for 2-3years until processing. DNA extraction was confirmed by polymerase chain reaction for human β-globin, and the presence of prostate-specific antigen (PSA) was quantified. The presence of the Y chromosome was detected using primers for sequences in the TSPY (Y7/Y8 and DYS14) and SRY genes. β-Globin was detected in all 10 samples, while 2 samples were positive for PSA. Half of the samples amplified the Y7/Y8 and DYS14 sequences of the TSPY gene and 30% amplified the SRY gene sequence of the Y chromosome. Four male samples and 1 female sample served as controls. Filter-paper spots stored for periods of up to 3years proved adequate for preserving genetic material from vaginal samples collected following sexual violence.