588 research outputs found
Management of undescended testis: italian experience of a single center of pediatric surgery
Abstract
The undescended testis (UDT) is a common male genital anomaly. Sub fertility and testicular hypotrophy are considered the principal long-term consequences
of UDT. There are two modes of treatment of UDT: hormonal and surgical treatment surgical that can be used alone or as complementary methods.
Testicular histology, testicular volume (TV) and hormonal evaluation are considered to be the most relevant measure to establish future potential fertility.
During follow-up each patient undergoes physical and ultrasound examination after three, twelve months and then five years. Serum level of gonadal hormone
(LH, FSH, Inhibin B, LDH, Free Testosterone and DHEA) is evaluated before surgery and six months after orchidopexy.
We assumed that testis biopsy is more predictive about future potential fertility than TV. Our patients have been found to have higher levels of LH and
FSH and lower levels of inhibin B. To discern the presence of an effect of hormonal treatment we decided to consider the Testicular Atrophy Index (TAI), which
is applicable only in unilateral UDT. Due to the necessity to consider also the case of bilateral UDT, we have introduced the normalized Testicular Atrophy Index
(TAIn).
Through the performed management, it has been possible to provide an estimate of the future fertility of these children. We noted that the degree of
reduction in testicular volume does not seem to correlate with the severity of histological findings, nor does it seem to affect future fertility. The patients with
a TAIn ≥ 20 % treated with preoperative and post-operative GnRHa therapy have a significant increase in TV after 5 years of follow-up, as shown by the
relative reduction of TAIn values. Immediate and delayed post-surgery complications have not occurred. In the cases treated with hormonal therapy, a slight
accentuation of secondary sexual characteristics occurs but it is completely regressed after discontinuation of the treatment (one month post-surgery). There
have been no recurrences UDT after orchidopexy
EFFECT OF Γ-AMINOBUTYRRIC ACID (GABA) EXPOSURE ON EMBRYOGENESIS OF PARACENTROTUS LIVIDUS AND IDENTIFICATION OF GABA-RECEPTOR GENES IN SEA URCHINS
Developmental processes are controlled by regulatory genes encoding for transcription factors
and signaling molecules. Functional relationships between these genes are described by gene
regulatory networks (GRN), models which allow integration of various levels of information.
The sea urchin embryo is an experimental model system which offers many advantages for the
analysis of GRN. Recently, the GRN that governs the biomineralization of the sea urchin
embryonic skeleton has begun to be deciphered. Preliminary evidence suggest that the γ-
aminobutyric acid (GABA) signaling pathway is involved in skeletal morphogenesis during
development of the sea urchin. GABA is a molecule synthesized by nearly all organism, from
bacteria to humans, and it acts through ionotropic and metabotropic receptors (GABAA-Rs and
GABAB-Rs, respectively).
We report that Paracentrotus lividus embryos exposed to GABA at concentrations ranging from
0.01 to 1.0 mM showed aberrations in axial patterning, with a dose dependent effect.
Washout experiments allowed to determine that the period of sensitivity is restricted from the
blastula to the gastrula stage.
In order to identify GABA-R genes we performed a comprehensive in silico analysis in selected
sea urchin species (P. lividus, Strongylocentrotus purpuratus, and Lytechinus variegatus), and in
phylogenetically related organisms, such as the hemichordate Saccoglossus kowalevskii, the
chordate Ciona intestinalis, and the nematode Caenorhabditis elegans.
By combining iteration of ab initio predictions and pairwise comparative methods, we identified
the orthologous genes encoding for GABAB1 and GABAB2, the two subunits which assemble
GABAB-R, and we confirmed that all of these organisms possess a unique α/β GABAA-R gene
pair clustered in the genome. Furthermore, we have observed that the reciprocal disposition of
GABAA-R genes is also evolutionarily conserved.
Interestingly, in adjacent position to these genes, we have identified an additional gene, which
shows significant sequence similarity to a invertebrate-specific GABAA-R gene. Indeed, such a
gene has been only identified in C. elegans, Drosophila melanogaster, and Nematostella
vectensis.
We also retrieved several cDNA sequences from staged EST databases of the three sea urchin
species inspected, indicating that these genes are actively transcribed during development. Some
selected cDNA plasmids were also isolated from P. lividus total RNA samples and fully
sequenced.
Hypothetical proteins were deduced and used for phylogenetic analysis, including a selection of
vertebrate and invertebrate GABAA-R subunit sequences. The resulting phylogenetic tree
strongly support the hypothesis that the sea urchins contain genes encoding for both
canonical and invertebrate-specific GABAA-R subunits. Such a collection of data should provide
a support to better understand the involvement of GABA-signalling pathway in the skeletal GR
Integración y adaptación de transferencias léxicas. YOLANDA HIPPERDINGER. Bahía Blanca: Universidad Nacional del Sur, 2001, 192 páginas
Spigelian Hernia in a 14-Year-Old Girl: A Case Report and Review of the Literature
Spigelian hernia (SH) is a surgical rarity in children, which occurs through slit-like defects in the anterior abdominal wall adjacent to the semilunar line, the convexity lateral line which joins the nine ribs to the pubic tubercle and signs the limit between the muscular and aponeurotic portion of transversus abdominis muscle. As there are no specific symptoms and signs, the diagnosis is difficult, especially in children. We report a case of SH that comes to our observation: a 14-year-old girl presented recurrent abdominal pain associated to intermittent palpable mass in the paraumbilical region. Starting from our case report, we review the literature of pediatric SH from 2000 to 2013 and we describe the anatomy, etiology, clinical presentation, instrumental diagnosis, and surgical technique of pediatric SH
La lengua wichí del chaco salteño. Aspectos fonológicos y morfosintácticos
El propósito de la tesis es describir la variedad de la lengua wichí –en todos sus niveles, es decir, fonología, morfosintaxis y léxico– que se habla en un grupo de comunidades ubicadas a orillas del río Pilcomayo, y que no ha sido documentada hasta el momento. Este trabajo está basado en datos primarios recogidos en sucesivos trabajos de campo iniciados en el año 2004.La metodología empleada es la que se utiliza en investigaciones de lingüística aplicada y sociolingüística: el método empírico-inductivo. Para la recolección de datos se emplearon las técnicas propias del trabajo de campo: registros directivos o no directivos. Nuestra investigación sigue los lineamientos teórico-metodológicos del funcionalismo y de los estudios tipológico-funcionales. En cuanto a su organización, se divide en siete capítulos en los que presentamos un panorama sociolingüístico de la lengua, luego trabajamos sobre el reconocimiento de las unidades fonológicas, los morfemas y las clases de palabras. En cuanto a la fonología hemos analizado la tipología silábica y hemos realizado una aproximación a los sistemas acentuales. Por otro lado, analizamos los procesos morfológicos derivativos y compositivos que hemos documentado en nuestro corpus. También las características morfosintácticas de la totalidad de las clases léxicas que identificamos. Finalmente, abordamos el estudio de las estructuras sintácticas: orden de los constituyentes, alineamiento sintáctico, tipos de cláusulas (simples y complejas, aunque no hemos profundizado en esta última). Concluimos que la lengua wichí es de carácter aglutinante y polisintético, con marcación en el núcleo. Asimismo, posee un sistema de alineamiento activo/inactivo que se verifica en los índices pronominales verbales (de tercera persona) que señalan el rol semántico de los participantes. Esto significa que distinguen entre participantes activos o agentivos y pasivos o pacientivos.
A demonstrator for bolometric interferometry
Bolometric Interferometry (BI) is one of the most promising techniques for
precise measurements of the Cosmic Microwave Background polarization. In this
paper, we present the results of DIBO (Demonstrateur d'Interferometrie
Bolometrique), a single-baseline demonstrator operating at 90 GHz, built to
proof the validity of the BI concept applied to a millimeter-wave
interferometer. This instrument has been characterized in the laboratory with a
detector at room temperature and with a 4 K bolometer. This allowed us to
measure interference patterns in a clean way, both (1) rotating the source and
(2) varying with time the phase shift among the two interferometer's arms.
Detailed modelisation has also been performed and validated with measurements.Comment: 15 pages, 14 figure
Habitual Joint Dislocations and Recurrent Multiple Hernias: An Unusual Connective Tissue Disease?
Purpose: Joint laxity and hernia defects are two well-defined conditions that are rarely described in association
in literature. The purpose of this study is to describe a peculiar case of connective tissue disorder, not yet defined,
whose features are habitual joint dislocations associated with recurrent and multiple hernias.
Methods: This is an unusual case regarding a 22 years old male adult, who presented shoulder, patellar,
mandibular habitual joint dislocations associated with groin, femoral, epigastric, umbilical, spigelian and lumbar
hernias. His phenotype, consisting of tall stature and joint laxity, recalls a similar-marfanoid habitus.
Results: Marfan Syndrome, Ehlers-Danlos syndrome, MEN-2B were excluded by specific assessments. The
aspecific clinical features of the patient do not consent the identification of an exact diagnosis.
Conclusion: This medical case, characterized by joint hypermobility and multiple recurrent hernias, probably
consists in an unacknowledged peculiar case of connective tissue disorder. Further investigations and identification
of subjects with similar features could be surely useful to diagnostic research and definitive characterization of
patient’s disease
Perceptualand cognitive factors imposing "speed limits" on reading rate: a study with the rapid serial visual presentation
Adults read at high speed, but estimates of their reading rate vary greatly, i.e., from 100 to 1500 words per minute (wpm). This discrepancy is likely due to different recording methods and to the different perceptual and cognitive processes involved in specific test conditions. The present study investigated the origins of these notable differences in RSVP reading rate (RR). In six experiments we investigated the role of many different perceptual and cognitive variables. The presence of a mask caused a steep decline in reading rate, with an estimated masking cost of about 200 wpm. When the decoding process was isolated, RR approached values of 1200 wpm. When the number of stimuli exceeded the short-term memory span, RR decreased to 800 wpm. The semantic context contributed to reading speed only by a factor of 1.4. Finally, eye movements imposed an upper limit on RR (around 300 wpm). Overall, data indicate a speed limit of 300 wpm, which corresponds to the time needed for eye movement execution, i.e., the most time consuming mechanism. Results reconcile differences in reading rates reported by different laboratories and thus provide suggestions for targeting different components of reading rate
Derivation and composition on Maká and Wichí (mataguaya family). From syntax to morphology
En este trabajo nos proponemos hacer una comparación entre los diversos procesos de formación de palabras, especialmente derivación y composición, que ocurren tanto en maká como wichí, dos lenguas de la familia mataguaya. Si bien se postula una relación de mayor semejanza o parentesco entre el chorote y el maká, por un lado, y el wichí y el nivaclé, por otro (Tovar 1964), consideramos que existen semejanzas formales y funcionales en los procesos de derivación y composición entre estas dos lenguas que pueden contribuir a indagar en los procesos de gramaticalización ocurridos en ellas. Para cumplir tal propósito, nos basamos en una perspectiva tipológico-funcional que abarca no solo la descripción estructural de los procesos de formación de palabras en cada una de las lenguas, sino también la comparación interlingüística. La investigación es de tipo descriptivo-documental.Our aim in this paper is to compare different word formation processes, especially those of derivation and compounding that take place in Maká and Wichí, both languages of the Mataguayan family. Although it has been established that there is a closer relation between Chorote and Maká, on one hand; and Wichí and Nivaclé on the other hand (Tovar 1964a y b), we propose that these two languages have more aspects in common and that this can help to study grammaticalization processes.To achieve this goal, we use a functional-typological approach that encompasses structural description as well as interlinguistic comparison. The research carried out for this paper is descriptive-documental.Fil: Spinelli, Silvia. Universidad Nacional de La Pampa; ArgentinaFil: Tacconi, Temis Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires; Argentin
Fungi and arsenic. Tolerance and bioaccumulation by soil saprotrophic species
Increasing arsenic environmental concentrations are raising worldwide concern for its impacts on human health and ecosystem functionality. In order to cope with arsenic contamination, bioremediation using fungi can represent an efficient, sustainable, and cost-effective technological solution. Fungi can mitigate arsenic contamination through different mechanisms including bioaccumulation. In this work, four soil saprotrophic fungi Absidia spinosa, Purpureocillium lilacinum, Metarhizium marquandii, and Cephalotrichum nanum, isolated from soils with naturally high arsenic concentrations, were tested for their ability to tolerate different sodium arsenite concentrations and accumulate As in different cultural conditions. pH medium after fungal growth was measured to study pH variation and metabolic responses. Arsenic bioaccumulation and its influence on the uptake of other elements were investigated through multi-elemental analysis using hydride generation atomic fluorescence spectrometry (HG-AFS), inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectroscopy (ICP-OES). Considering the increasing interest in siderophore application for metal bioremediation, the production of siderophores and their affinity for both Fe and As were also evaluated. All species were able to tolerate and accumulate As in their biomass in all of the tested conditions and produced siderophores with different affinities for Fe and As. The results suggest that the tested fungi are attractive potential candidates for the bioremediation of As contaminated soil and worthy of further investigation
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