951 resultados para biologic samples
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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In dieser Arbeit werden neue Rylenimide und Anwendungsmöglichkeiten für diese Farbstoffklasse beschrieben, die sich durch hohe Photostabilitäten und hohe Fluoreszenzquantenausbeute auszeichnet. Ziel dieser Arbeit war es, durch systematische Wahl der Substituenten in den Imidstrukturen und/oder den bay-Regionen von Rylendiimidfarbstoffen vollkommen neue Produkteigenschaften zu verwirklichen, Reaktionen bzw. Anwendungen zu ermöglichen und den Aufbau von komplexeren Chromophorarchitekturen zu gestatten. Das Strukturmotiv des Terrylendiimids nahm dabei die zentrale Rolle ein. Die Arbeit wurde in vier Kapitel aufgeteilt. Das Ziel des ersten Kapitels war es, wasserlösliche Terrylendiimide zur Untersuchung von biologischen Proben im Wellenlängenbereich über 600 nm einzusetzen. Ein wasserlösliches Terrylendiimid erwies sich dabei als deutlich photostabiler als zwei weitverbreitete Fluoreszenzfarbstoffe. Eine erste Proteinmarkierung mit monofunktionellem Farbstoff wurde an Proteinmolekülen erfolgreich durchgeführt. Durch gezielte Modifikationen konnten zwei Terrylendiimide hergestellt werden, die sich noch deutlich besser zum Abbilden von Zellstrukturen eignen. In dem zweiten Kapitel spielte die Löslichkeit von Rylendiimiden in organischen Lösungsmitteln eine zentrale Rolle. Es wurde eine Rylendiimidserie hergestellt, deren löslichkeitssteigernde Gruppen eine Organisation der Moleküle in ausgedehnten Stapelstrukturen nicht verhindern. Mit dieser Serie konnte das flüssigkristalline Verhalten und die Selbstorganisation in der Rylendiimidreihe untersucht werden. Aufbauend auf diesen Ergebnissen wurde die Selbstorganisation der Diimide in Donor-Akzeptor Gemischen untersucht. In STM-Experimenten konnten für alle drei Diimide selbstorganisierte Monoschichten mit dem Rastertunnelmikroskop mit molekularer Auflösung abgebildet werden. Darüber hinaus wurden in diesem Kapitel die ersten organischen Feldeffekttransistoren (OFET) auf der Basis des synthetisierten Terrylendiimids beschrieben. Im Rahmen eines Projektes in dem die elektronische Energieübertragung in Donor-Akzeptor-Diaden mit Hilfe von Einzelmolekülspektroskopie untersucht wird, wurde eine Perylendiimid-Terrylediimid Diade hergestellt. Die geringere Photostabilität des Donors ermöglichte zeitaufgelöste Einzelmolekül-messungen der Akzeptoremission mit und ohne Energietransfer vom Donor auf den Akzeptor. Durch diese Messungen konnten die Zeitkonstanten des Energietransfers für einzelne Diaden ermittelt werden. Ein weiterer Chromophor aus diesem Donor-Akzeptor-Paar soll die Möglichkeit eröffnen, den Energiefluß im Molekül gezielt zu manipulieren. Dazu wurde ein Donorchromophor mit zwei Akzeptoren in einem Multichromophor kombiniert. Im Rahmen der Synthesen dieser Arbeit wurden Terrylendiimide hergestellt, die in einer Imidstruktur eine Halogenfunktion trugen. Diese waren wichtige Synthesebausteine zum Aufbau von komplexen Chromophorarchitekturen. Ziel eines weiteren Kapitels war es, ein Terrylendiimid herzustellen, das als Sensibilisatorfarbstoff gemeinsam mit dem Haupt-Antennenkomplex von höheren Pflanzen LHCII in einer photoelektrochemischen Farbstoff-Solarzelle integriert werden konnte. Das hergestellte Terrylendiimid mit Carbonsäuregruppe eignete sich für Farbstoffsolarzellen auf Zinndioxidbasis.
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The Kenya (a.k.a., Gregory) Rift is a geologically active area located within the eastern branch of the larger East African Rift System (EARS). The study area is located in the southern Kenya Rift between 1° South and the Kenya-Tanzania border (covering approximately 1.5 square degrees, semi-centered on Lake Magadi) and is predominantly filled with extrusive igneous rocks (mostly basalts, phonolites and trachytes) of Miocene age or younger. Sediments are thin, less than 1.5Ma, and are confined to small grabens. The EARS can serve both as an analogue for ancient continental rifting and as a modern laboratory to observe the geologic processes responsible for rifting. This study demonstrates that vintage (as in older, quality maps published by the Kenya Geological Survey, that may be outdated based on newer findings) quarter-degree maps can be successfully combined with recently published data, and used to interpret satellite (mainly Landsat 7) images to produce versatile, updated digital maps. The study area has been remapped using this procedure and although it covers a large area, the mapping retains a quadrangle level of detail. Additionally, all geologic mapping elements (formations, faults, etc.) have been correlated across older map boundaries so that geologic units don't end artificially at degree boundaries within the study area. These elements have also been saved as individual digital files to facilitate future analysis. A series of maps showing the evolution of the southern Kenya rift from the Miocene to the present was created by combining the updated geologic map with age dates for geologic formations and fault displacements. Over 200 age dates covering the entire length of the Kenya Rift have been compiled for this study, and 6 paleo-maps were constructed to demonstrate the evolution of the area, starting with the eruption of the Kishalduga and Lisudwa melanephelinites onto the metamorphic basement around 15Ma. These eruptions occurred before the initial rift faulting and were followed by a massive eruption of phonolites between 13-10 Ma that covered most of the Kenya dome. This was followed by a period of relative quiescence, until the initial faulting defined the western boundary of the rift around 7Ma. The resulting graben was asymmetrical until corresponding faults to the east developed around 3Ma. The rift valley was flooded by basalts and trachytes between 3Ma and 700ka, after which the volcanic activity slowed to a near halt. Since 700ka most of the deposition has been comprised of sediments, mainly from lakes occupying the various basins in the area. The main results of this study are, in addition to a detailed interpretation of the rift development, a new geologic map that correlates dozens of formations across old map boundaries and a compilation of over 300 age dates. Specific products include paleomaps, tables of fault timing and displacement, and volume estimates of volcanic formations. The study concludes with a generalization of the present environment at Magadi including discussions of lagoon chemistry, mantle gases in relation to the trona deposit, and biology of the hot springs. Several biologic samples were collected during the 2006 field season in an attempt to characterize the organisms that are commonly seen in the present Lake Magadi environment. Samples were selected to represent the different, distinctive forms that are found in the hotsprings. Each sample had it own distinctive growth habit, and analysis showed that each was formed by a different cyanobacterial. Actual algae was rare in the collected samples, and represented by a few scattered diatoms.
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The Amazonian manatee (Trichechus inunguis) is endemic in the Amazonian basin and is the only exclusively fresh water sirenian. Historically hunted on a large scale, this species is now considered endangered, and Studies on the reproductive physiology are critical for the improvement of reproductive management of captive and wild Populations of manatees. The aim of this Study was to verify the viability of androgen measurement in saliva, lacrimal, urine, and fecal samples of the Amazonian manatee by conducting a hormone challenge. Two adult male manatees (A-1 and A-2) were Submitted to an experimentation protocol of 12 day (D1 to D10). On D0, the animals received an intramuscular injection of gonadotropin-releasing hormone (GnRH)-analogue. Salivary, lacrimal, urinary, and fecal samples were collected daily (between 0800 hours and 0900 hours) and frozen at -20 degrees C until assayed. Fecal samples were lyophilized, extracted with 80% methanol, and diluted in buffer before the radioimmunoassay (RIA). Urine samples underwent acid hydrolysis and were diluted in depleted bovine serum. Salivary and lacrimal samples were assayed without the extraction step. Hormonal assays were conducted with a commercial testosterone RIA kit. An androgen peak (>median + 2 interquartile range [IQR]) was observed in all matrices of both animals, although it was less prominent in the lacrimal samples of A-2. However, the fecal androgen peak (A-1 peak = 293.78 ng/g dry feces, median [IQR] = 143.58 [32.38] ng/g dry feces; A-2 peak = 686.72 ng/g dry feces, median [IQR] = 243.82 [193.16] ng/g dry feces) occurred later than urinary (A-1 peak = 648.16 ng/mg creatinine [Cr], median [IQR] = 23.88 [30.44] ng/mg Cr; A-2 peak = 370.44 ng/mg Cr, median [IQR] = 113.87 [117.73] ng/mg Cr) and salivary (A-1 peak = 678.89 pg/ml, median [IQR] = 103.69 [119.86] pg/ml; A-2 peak = 733.71 pg/ml, median [IQR] = 262.92 [211.44] pg/ml) androgen peaks. These intervals appear to be correlated with the long digesta passage time in this species. The salivary and urinary peaks were closely associated. These results demonstrate that androgen concentrations in saliva, urine, or feces samples reflect reliably physiologic events and are a powerful tool for noninvasive reproductive monitoring of Amazonian manatees.
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Cryptosporidiosis has recently attracted attention as an emerging waterborne and foodborne disease as well as an opportunistic infection in HIV infected individuals. The lack of genetic information, however, has resulted in confusion in the taxonomy of Cryptosporidium parasites and in the development of molecular tools for the identification and typing of oocysts in environmental samples. Phylogenetic analysis of the small subunit ribosomal RNA (SSU rRNA) gene has shown that the genus Cryptosporidium is comprised of several distinct species. Our data show the presence of at least four species: C. parvum, C. muris, C. baileyi and C. serpentis (C. meleagridis, C. nasorum and C. felis were not studied). Within each species, there is some sequence variation. Thus, various genotypes (genotype 1, genotype 2, guinea pig genotype, monkey genotype and koala genotype, etc.) of C. parvum differ from each other in six regions of the SSU rRNA gene. Information on polymorphism in Cryptosporidium parasites has been used in the development of species and strain-specific diagnostic tools. Use of these tools in the characterization of oocysts various samples indicates that C. parvum genotype 1 is the strain responsible for most human Cryptosporidium infections. In contrast, genotype 2 is probably the major source for environmental contamination of environment, and has been found in most oysters examined from Chesapeake Bay that serve as biologic monitors of surface water. Parasites of Cryptosporidium species other than C. parvum have not been detected in HIV+ individuals, indicating that the disease in humans is caused only by C. parvum.
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In obstetrics, premature rupture of the membranes (PROM) is a frequent observation which is responsible for many premature deliveries. PROM is also associated with an increased risk of fetal and maternal infections. Early diagnosis is mandatory in order to decrease such complications. Despite that current biological tests allowing the diagnosis of PROM are both sensitive and specific, contamination of the samples by maternal blood can induce false positive results. Therefore, in order to identify new potential markers of PROM (present only in amniotic blood, and absent in maternal blood), proteomic studies were undertaken on samples collected from six women at terms (pairs of maternal plasma and amniotic fluid) as well as on four samples of amniotic fluid collected from other women at the 17(th) week of gestation. All samples (N = 16) were analyzed by two-dimensional (2-D) high-resolution electrophoresis, followed by sensitive silver staining. The gel images were studied using bioinformatic tools. Analyses were focused on regions corresponding to pI between 4.5 and 7 and to molecular masses between 20 and 50 kDa. In this area, 646 +/- 113 spots were detected, and 27 spots appeared to be present on the gels of amniotic fluid, but were absent on those of maternal plasma. Nine out of these 27 spots were also observed on the gels of the four samples of amniotic fluids collected at the 17(th) week of pregnancy. Five of these 9 spots were unambiguously detected on preparative 2-D gels stained by Coomassie blue, and were identified by mass spectrometry analyses. Three spots corresponded to fragments of plasma proteins, and 2 appeared to be fragments of proteins not known to be present in plasma. These 2 proteins were agrin (SWISS-PROT: O00468) and perlecan (SWISS-PROT: P98160). Our results show that proteomics is a valuable approach to identify new potential biological markers for future PROM diagnosis.
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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.
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Infections of the central nervous systems (CNS) present a diagnostic problem for which an accurate laboratory diagnosis is essential. Invasive practices, such as cerebral biopsy, have been replaced by obtaining a polymerase chain reaction (PCR) diagnosis using cerebral spinal fluid (CSF) as a reference method. Tests on DNA extracted from plasma are noninvasive, thus avoiding all of the collateral effects and patient risks associated with CSF collection. This study aimed to determine whether plasma can replace CSF in nested PCR analysis for the detection of CNS human herpesvirus (HHV) diseases by analysing the proportion of patients whose CSF nested PCR results were positive for CNS HHV who also had the same organism identified by plasma nested PCR. In this study, CSF DNA was used as the gold standard, and nested PCR was performed on both types of samples. Fifty-two patients with symptoms of nervous system infection were submitted to CSF and blood collection. For the eight HHV, one positive DNA result-in plasma and/or CSF nested PCR-was considered an active HHV infection, whereas the occurrence of two or more HHVs in the same sample was considered a coinfection. HHV infections were positively detected in 27/52 (51.9%) of the CSF and in 32/52 (61.5%) of the plasma, difference not significant, thus nested PCR can be performed on plasma instead of CSF. In conclusion, this findings suggest that plasma as a useful material for the diagnosis of cases where there is any difficulty to perform a CSF puncture.
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The taxonomic position of a bacterium isolated from water samples from the Rio Negro, in Amazon, Brazil, was determined by using a polyphasic approach. The organism formed a distinct phyletic line in the Chromobacterium 16S rRNA gene tree and had chemotaxonomic and morphological properties consistent with its classification in this genus. It was found to be closely related to Chromobacterium vaccinii DSM 25150(T) (98.6 % 16S rRNA gene similarity) and shared 98.5 % 16S rRNA gene similarity with Chromobacterium piscinae LGM 3947(T). DNA-DNA relatedness studies showed that isolate CBMAI 310(T) belongs to distinct genomic species. The isolate was readily distinguished from the type strain of these species using a combination of phenotypic and chemotaxonomic properties. Thus, based on genotypic and phenotypic data, it is proposed that isolate CBMAI 310(T) (=DSM 26508(T)) be classified in the genus Chromobacterium as the type strain of a novel species, namely, Chromobacterium amazonense sp. nov.
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Ammonium nitrate fuel oil (ANFO) is an explosive used in many civil applications. In Brazil, ANFO has unfortunately also been used in criminal attacks, mainly in automated teller machine (ATM) explosions. In this paper, we describe a detailed characterization of the ANFO composition and its two main constituents (diesel and a nitrate explosive) using high resolution and accuracy mass spectrometry performed on an FT-ICR-mass spectrometer with electrospray ionization (ESI(±)-FTMS) in both the positive and negative ion modes. Via ESI(-)-MS, an ion marker for ANFO was characterized. Using a direct and simple ambient desorption/ionization technique, i.e., easy ambient sonic-spray ionization mass spectrometry (EASI-MS), in a simpler, lower accuracy but robust single quadrupole mass spectrometer, the ANFO ion marker was directly detected from the surface of banknotes collected from ATM explosion theft.
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Conventional reflectance spectroscopy (NIRS) and hyperspectral imaging (HI) in the near-infrared region (1000-2500 nm) are evaluated and compared, using, as the case study, the determination of relevant properties related to the quality of natural rubber. Mooney viscosity (MV) and plasticity indices (PI) (PI0 - original plasticity, PI30 - plasticity after accelerated aging, and PRI - the plasticity retention index after accelerated aging) of rubber were determined using multivariate regression models. Two hundred and eighty six samples of rubber were measured using conventional and hyperspectral near-infrared imaging reflectance instruments in the range of 1000-2500 nm. The sample set was split into regression (n = 191) and external validation (n = 95) sub-sets. Three instruments were employed for data acquisition: a line scanning hyperspectral camera and two conventional FT-NIR spectrometers. Sample heterogeneity was evaluated using hyperspectral images obtained with a resolution of 150 × 150 μm and principal component analysis. The probed sample area (5 cm(2); 24,000 pixels) to achieve representativeness was found to be equivalent to the average of 6 spectra for a 1 cm diameter probing circular window of one FT-NIR instrument. The other spectrophotometer can probe the whole sample in only one measurement. The results show that the rubber properties can be determined with very similar accuracy and precision by Partial Least Square (PLS) regression models regardless of whether HI-NIR or conventional FT-NIR produce the spectral datasets. The best Root Mean Square Errors of Prediction (RMSEPs) of external validation for MV, PI0, PI30, and PRI were 4.3, 1.8, 3.4, and 5.3%, respectively. Though the quantitative results provided by the three instruments can be considered equivalent, the hyperspectral imaging instrument presents a number of advantages, being about 6 times faster than conventional bulk spectrometers, producing robust spectral data by ensuring sample representativeness, and minimizing the effect of the presence of contaminants.
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Several characteristics are important in a traceability system of animal products, such as age at slaughter, breed composition, besides information of the productive chain. In general, the certification agent records information about the animals and the system which it came from, although cannot guarantee that the slaughtering, meat processing and distribution are error proof. Besides, there is a differential price, at least at the international market, based on sex and breed composition of the animals. Genetic markers allow identification of characteristics controlled in the beef cattle traceability program, as sex and breed composition, in order to correctly identify and appraise the final product for the consumer. The hypothesis of this study was that the majority beef samples retailed in the local market originate from female with a great participation of zebu breeds. Therefore, the objective of this work was to characterize retail beef samples with DNA markers that identify cattle sex and breed composition. Within 10 beef shops localized in Pirassununga, SP, Brazil, 61 samples were collected, all were genotyped as harboring Bos taurus mitochondrial DNA and 18 were positive for the Y chromosome amplification (male). For the marker sat1711b-Msp I the frequency of the allele A was 0.278 and for the marker Lhr-Hha I the frequency of the allele T was 0.417. The results of sat1711b-Msp I and Lhr-Hha I allelic frequencies are suggestive that the proportion of indicus genome compared with the taurine genome in the market meat is smaller than the observed in the Nellore breed. The procedure described in this study identified sex and subspecies characteristics of beef meat samples, with potential application in meat products certification in special as an auxiliary tool in beef cattle traceability programs.