1,770 research outputs found

    Transcriptome of the deep-sea black scabbardfish, Aphanopus carbo (Perciformes: Trichiuridae) : tissue-specific expression patterns and candidate genes associated to depth adaptation

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    Deep-sea fishes provide a unique opportunity to study the physiology and evolutionary adaptation to extreme environments. We carried out a high throughput sequencing analysis on a 454 GS-FLX titanium plate using unnormalized cDNA libraries from six tissues of A. carbo. Assemblage and annotations were performed by Newbler and InterPro/Pfam analyses, respectively. The assembly of 544,491 high quality reads provided 8,319 contigs, 55.6% of which retrieved blast hits against the NCBI nonredundant database or were annotated with ESTscan. Comparison of functional genes at both the protein sequences and protein stability levels, associated with adaptations to depth, revealed similarities between A. carbo and other bathypelagic fishes. A selection of putative genes was standardized to evaluate the correlation between number of contigs and their normalized expression, as determined by qPCR amplification. The screening of the libraries contributed to the identification of new EST simple-sequence repeats (SSRs) and to the design of primer pairs suitable for population genetic studies as well as for tagging and mapping of genes. The characterization of the deep-sea fish A. carbo first transcriptome is expected to provide abundant resources for genetic, evolutionary, and ecological studies of this species and the basis for further investigation of depth-related adaptation processes in fishes.Publisher PDFPeer reviewe

    Evolution of Thermotolerance and Variation in the Heat Shock Protein, Hsp70

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    Low to moderate levels of stress induce a class of molecular chaperones called heat shock proteins (Hsps), which protect cells, tissues and whole organisms from more severe stress. In higher Eukaryotes, Hsp70 is one of the principle heat-induced chaperones. This response is general, and how much Hsp70 an animal produces correlates with the level of stress to which it is exposed. Nonetheless, definitively linking high Hsp70 expression as an adaptation to stress tolerance is problematic, because organisms and cells respond to stress in many ways. By molecular manipulation of Hsp70 in one animal group, Drosophila, differences in hsp70 copy number are shown to directly influence heat-induced expression of Hsp70 and tolerance of heat. However, too high an expression level of Hsp70 can harm individuals during periods of rapid growth. This strong physiological relationship between Hsp70 concentration and thermotolerance, along with Hsp70\u27s remarkable degree of interspecific coding sequence conservation, suggest that hsp70 regulatory elements may evolve as an adaptation in diverse species to their thermal environments. To examine this possibility, correlative studies within species and research on phylogenetic covariation between these traits is reviewed with a focus on Drosophila species. However, the techniques and results discussed should broadly apply to other animal groups where evolutionary approaches can be used to test whether genetic variation in both thermotolerance and Hsp expression within and among species select locally on either hsp70 sequence and/or expression

    Exames andrológicos em bovinos de carne na região do Alentejo, Portugal#

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    É referida a importância do exame andrológico em bovinos explorados em regime extensivo e como este serviço médico-veterinário tem vindo a ser oferecido em Portugal. Descrevem-se os resultados encontrados por uma equipa médico-veterinária em contexto prático na região do Alentejo e discute-se como podem ser avaliados estes resultados com critérios o mais objectivo possiveis para selecção dos melhores touros

    Interaction between vortices in models with two order parameters

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    The interaction energy and force between widely separated strings is analyzed in a field theory having applications to superconducting cosmic strings, the SO(5) model of high-temperature superconductivity, and solitons in nonlinear optics. The field theory has two order parameters, one of which is broken in the vacuum (giving rise to strings), the other of which is unbroken in the vacuum but which could nonetheless be broken in the core of the string. If this does occur, there is an effect on the energetics of widely separated strings. This effect is important if the length scale of this second order parameter is longer than that of the other fields in the problem.Comment: 11 pages, 3 figures. Minor changes in the text. Accepted for publication in Phys. Rev.

    Semi-automatic quantification of the epicardial fat in CT images

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    In this work we present a technique to automatically or semi-automatically quantify the epicardial fat in noncontrasted Computed Tomography (CT) images. In CT images, the epicardial fat is very close to the pericardial fat, distincted only by the pericardium. The pericardium appears in the image as a very thin line, very hard to discriminate. To enhance the pericardium line and to remove noise as well as higher intensities due to calcifications, some pre-processing was applied, namely region growing, thresholding and average filtering techniques. To detect the pericardium line an algorithm was developed that considerer the heart anatomy to find control points belonging to that line. From the points detected an interpolation was done based on the cubic spline method. This method was also improved to avoid incorrect interpolation that occurs when one of the coordinates of the points is repeated. After having the line delineation, the pixels bellow the line were counted, considering only the pixels in the fat window (-190 to -30 Hounsfiel Units). In 10 images tested, in 4 the system fully automatically returned the correct value for epicardial fat. In the other 6 the system needed a small correction by moving 1 or 2 points to return the correct value of epicardial fat. The values of the automatic quantification were compared to the values obtained by the manual process, having 10% as maximum error allowed. We concluded that this method is able to, automatically or with a small interaction, return the value of the epicardial fat, for the non contrast CT images tested

    Isolated left ventricular apical hypoplasia

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    Winding Number Correlation Functions and Cosmic String Formation

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    We develop winding number correlation functions that allow us to assess the role of field fluctuations on vortex formation in an Abelian gauge theory. We compute the behavior of these correlation functions in simple circumstances and show how fluctuations are important in the vicinity of the phase transition. We further show that, in our approximation, the emerging population of long/infinite string is produced by the classical dynamics of the fields alone, being essentially unaffected by field fluctuations.Comment: Latex file, 27 pages. 8 figures, available in compressed form by anonymous ftp from ftp://euclid.tp.ph.ic.ac.uk/papers/94-5_39.fig Latex and postscript versions also available at http://euclid.tp.ph.ic.ac.uk/Papers/index.htm

    DESCRIÇÃO DE TRÊS CASOS DE CRIPTORQUIDISMO EM EQUINOS DE RAÇA QUARTO DE MILHA EM PORTUGAL

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    O criptorquidismo consiste na não-descida dos testículos para o escroto, podendo ser uni ou bilateral. Cerca de 10% dos casos são de criptorquidismo bilateral e as situações unilaterais ocorrem frequentemente do lado esquerdo. Os testículos podem localizar-se na cavidade abdominal, no canal inguinal ou no tecido subcutâneo junto ao anel inguinal externo. As características das lesões macro e microscópicas do(s) testículo(s) dependem da idade do cavalo e da localização do testículo. Normalmente a observação macroscópica revela atrofia pronunciada e aumento da consistência. No exame histopatológico observa-se hipoplasia das células da linha germinativa e, em cavalos idosos, fibrose ao nível das túnicas. Os cavalos com criptorquidismo bilateral são estéreis mas, mantendo-se a produção de testosterona pelas células de Leydig, o comportamento sexual masculino não é alterado, apresentando-se, por vezes, estes animais mais agressivos que os não-criptorquídeos. Em equinos é considerado uma situação hereditária com carácter dominante, que ocorre com prevalência elevada em determinadas raças nomeadamente no American Quarter Horse (Quarto de Milha). Assim, mesmo os cavalos com criptorquidismo unilateral, que ainda apresentam de sémen, não devem ser utilizados para a reprodução devendo ser recomendada a sua castração. A castração pode ser efectuada por acesso inguinal, parainguinal, suprapúbico paramediano ou no flanco. Recentemente tem-se desenvolvido a castração por laparoscopia com o cavalo em estação ou em decúbito. O presente trabalho refere três casos de critptorquidismo esquerdo, em cavalos Quarto de Milha, castrados no Hospital Veterinário da Universidade de Évora (HVUE), com 2 1/2, 3 ½ e 6 anos de idade. Os testículos ectópicos localizavam-se, respectivamente, no anel inguinal, no tecido sub-cutâneo e na cavidade abdominal. A castração do cavalo cujo testículo se encontrava sub-cutâneo, junto ao anel inguinal externo, realizou-se por acesso inguinal, com o cavalo sedado e em estação. As outras duas cirurgias realizaram-se sob anestesia geral (por via inalatória) com os cavalos em decúbito dorsal sendo ambas iniciadas por acesso inguinal. O testículo de localização abdominal, teve que ser extraído por acesso parainguinal, dada a impossibilidade de exteriorização pelo anel inguinal. Ao exame macroscópico os testículos ectópicos encontravam-se atrofiados. O testículo com localização subcutânea apresentava forma irregular e os de localização no anel inguinal e na cavidade abdominal apresentavam, respectivamente, aumento da consistência e diminuição da mesma. Ao exame histopatológico observou-se, em todas as amostras, hipoplasia e degenerescência testicular severa sobretudo das células da linha germinativa, sendo que o testículo com localização abdominal apresentava ausência quase total destas células e também alterações degenerativas das células de Sertoli.#The cryptorchidism refers to the retention of one (unilateral) or both (bilateral) testicles and its absence in the scrotum. 10% of the cases of cryptorchidism are bilateral and the unilateral cases are frequently observed on the left side. The ectopic testicles can be located in the abdominal cavity, the inguinal ring or the sub-cutaneous tissue near the external inguinal ring. The macroscopic and microscopic lesions observed in the testicles depend both from the animal’s age as well as from the testicles’s location. More often the macroscopic examination reveals a marked atrophic testicle and a harder consistency of it. On the hystopathological exam we observe hypoplasia of the cells of the germinative pathway and in older horses a pronounced fibrosis in the area of the tunics. Horses with bilateral cryptorchidism suffer from sterility, however since the Leydig cells still produce testosterone, the mating behaviour and secondary sexual characteristics suffer no changes, horses are sometimes even more aggressive than non-cryptorchids horses. Cryptorchidism in horses is considered a hereditary situation with dominant character and has a high prevalence in some horse breeds like the American Quarter Horse. Concerning this fact, horses with this pathology, even if is unilateral and even with production of semen, should not be used as stallions and its castration should be recommended. The castration can be performed by several “traditional” approaches but presently some surgeons prefer the laparoscopic approach with the horse standing or in dorsal recumbency. The present work refers to three cases of left side cryptorchidism (unilateral) in American Quarter Horse that were castrated in the Hospital Veterinário da Universidade de Évora (HVUE). The three horses were 2 1/2, 3½ and 6 years old. The ectopic testicles were located in the inguinal ring (the 2 ½ years old horse), sub-cutaneous tissue (the 3½ years old horse) and in the abdominal cavity (the 6 years old horse). The surgery performed for the testicle located in the subcutaneous tissue was performed by inguinal approach with the animal standing and sedated. The other two surgeries were both performed with general inhalant anaesthesia with the animal in dorsal recumbency. Both surgeries were initially done by inguinal approach being the inguinal testicle well exteriorized by this approach. The intra abdominal testicle was impossible to remove through the inguinal ring so the para inguinal approach was used to exteriorize it. In the macroscopic examination all ectopic testicles were severely atrophic. The testicle removed from the subcutaneous tissue presented an irregular shape and the other testicles presented changes in consistency with higher consistency for the inguinal ring testicle and decreased consistency for the intra abdominal one. In the hystopathological examination, hypoplasia and severe testicular degenerative changes were observed in all samples especially in the germinative cells. In intra abdominal testicle these cells are almost absent and the Sertoli cells had marked degenerative changes
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