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Search Results: 1 - 10 of 788355 matches for " Andrés C. A. Culasso "
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Molecular Survey of Hepatitis C Virus in the Touristic City of Mar Del Plata, Argentina
Andrés C. A. Culasso, Mercedes Elizalde, Rodolfo H. Campos, Luciana Barbini
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0044757
Abstract: The global epidemiology of Hepatitis C Virus (HCV) may be roughly described by two groups of genotypes: the worldwide distributed ones (subtypes 1a, 1b, 2a and 3a, among others) and the endemic ones (subtypes 4a, 5a, 6a, among others). Epidemiological and population dynamic studies of the worldwide distributed genotypes have shown that subtypes 1a and 3a are common among intravenous drug users (IDUs) and that they are also in expansion in some countries. The molecular survey of HCV provides some clues about the epidemiological status of the infections in a local scale and the phylogenetic and demographic reconstruction analyses complement this study by inferring whether the infections of certain subtypes are in a steady state or expanding. Here, a molecular survey of the HCV variants that circulate in the touristic city of Mar del Plata (Buenos Aires, Argentina) was performed in samples obtained from 42 patients. The subtypes detected were 1a (32 patients), 3a (8 patients) and 1b (2 patients). The demographic history of subtype 1a inferred using the sequence data showed an exponential growth in the 1990′s. The period of viral expansion was delayed compared with that observed for the same genotype in other countries where the transmission was associated with IDUs. Also, the phylogeographic analysis of HCV-1a showed a statistically significant association between the location of the samples and the phylogeny, which may be the result of the local transmission of HCV in the city. The molecular analysis helped in the description of the complex epidemiological context of a touristic city, and pointed out that some sanitary measures should be taken in order to reduce the transmission of HCV (and maybe of HIV) among IDUs.
Hepatitis C Virus Diversification in Argentina: Comparative Analysis between the Large City of Buenos Aires and the Small Rural Town of O'Brien
Marcelo D. Golemba, Andrés C. A. Culasso, Federico G. Villamil, Patricia Bare, Adrián Gadano, Ezequiel Ridruejo, Alfredo Martinez, Federico A. Di Lello, Rodolfo H. Campos
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0084007
Abstract: Background The estimated prevalence of HCV infection in Argentina is around 2%. However, higher rates of infection have been described in population studies of small urban and rural communities. The aim of this work was to compare the origin and diversification of HCV-1b in samples from two different epidemiological scenarios: Buenos Aires, a large cosmopolitan city, and O'Brien, a small rural town with a high prevalence of HCV infection. Patients and Methods The E1/E2 and NS5B regions of the viral genome from 83 patients infected with HCV-1b were sequenced. Phylogenetic analysis and Bayesian Coalescent methods were used to study the origin and diversification of HCV-1b in both patient populations. Results Samples from Buenos Aires showed a polyphyletic behavior with a tMRCA around 1887–1900 and a time of spread of infection approximately 60 years ago. In contrast, samples from óBrien showed a monophyletic behavior with a tMRCA around 1950–1960 and a time of spread of infection more recent than in Buenos Aires, around 20–30 years ago. Conclusion Phylogenetic and coalescence analysis revealed a different behavior in the epidemiological histories of Buenos Aires and óBrien. HCV infection in Buenos Aires shows a polyphyletic behavior and an exponential growth in two phases, whereas that in O'Brien shows a monophyletic cluster and an exponential growth in one single step with a more recent tMRCA. The polyphyletic origin and the probability of encountering susceptible individuals in a large cosmopolitan city like Buenos Aires are in agreement with a longer period of expansion. In contrast, in less populated areas such as O'Brien, the chances of HCV transmission are strongly restricted. Furthermore, the monophyletic character and the most recent time of emergence suggest that different HCV-1b ancestors (variants) that were in expansion in Buenos Aires had the opportunity to colonize and expand in O’Brien.
Phylodynamics of Hepatitis C Virus Subtype 2c in the Province of Córdoba, Argentina
Viviana E. Ré,Andrés C. A. Culasso,Silvia Mengarelli,Adrián A. Farías,Fabián Fay,María B. Pisano,Osvaldo Elbarcha,Marta S. Contigiani,Rodolfo H. Campos
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0019471
Abstract: The Hepatitis C Virus Genotype 2 subtype 2c (HCV-2c) is detected as a low prevalence subtype in many countries, except in Southern Europe and Western Africa. The current epidemiology of HCV in Argentina, a low-prevalence country, shows the expected low prevalence for this subtype. However, this subtype is the most prevalent in the central province of Córdoba. Cruz del Eje (CdE), a small rural city of this province, shows a prevalence for HCV infections of 5%, being 90% of the samples classified as HCV-2c. In other locations of Córdoba Province (OLC) with lower prevalence for HCV, HCV-2c was recorded in about 50% of the samples. The phylogenetic analysis of samples from Córdoba Province consistently conformed a monophyletic group with HCV-2c sequences from all the countries where HCV-2c has been sequenced. The phylogeographic analysis showed an overall association between geographical traits and phylogeny, being these associations significant (α = 0.05) for Italy, France, Argentina (places other than Córdoba), Martinique, CdE and OLC. The coalescence analysis for samples from CdE, OLC and France yielded a Time for the Most Common Recent Ancestor of about 140 years, whereas its demographic reconstruction showed a “lag” phase in the viral population until 1880 and then an exponential growth until 1940. These results were also obtained when each geographical area was analyzed separately, suggesting that HCV-2c came into Córdoba province during the migration process, mainly from Europe, which is compatible with the history of Argentina of the early 20th century. This also suggests that the spread of HCV-2c occurred in Europe and South America almost simultaneously, possibly as a result of the advances in medicine technology of the first half of the 20th century.
Enterococos resistentes a vancomicina: prevalencia y factores asociados a la colonización intestinal en pacientes oncológicos del Hospital de Ni os de Córdoba Vancomycin-resistant enterococci: prevalence and factors associated with intestinal colonization in oncology patients from Hospital de Ni os de Córdoba
A. L. Reale,M. L. Depetri,C. Culasso,M. Paviolo
Revista argentina de microbiolog?-a , 2009,
Abstract: Los enterococos resistentes a vancomicina (EVR) tienen un importante impacto sobre la población pediátrica oncológica. Los objetivos del presente estudio fueron conocer la prevalencia de colonización intestinal por EVR en pacientes oncológicos, identificar los factores de riesgo que predisponen a la colonización durante la hospitalización y determinar el perfil de resistencia de los EVR a diferentes agentes antimicrobianos. Se estudiaron todos los ni os de entre un mes y 16 a os de edad con enfermedad oncológica que ingresaron en el protocolo, de los internados desde octubre de 2006 hasta abril de 2007 en la Unidad de Oncohematología del Hospital de Ni os la Santísima Trin idad de Córdoba (Argentina). Se investigó la colonización intestinal con EVR al ingreso, a las 72 h y semanalmente durante la internación. Se obtuvieron 333 muestras de 67 pacientes y se aislaron EVR de 12 pacientes, lo que arroja una prevalencia de 17,9%. De los 28 aislamientos estudiados (uno por paciente), 10 fueron Enterococcus faecium y 2 Enterococcus faecalis, ambos con fenotipo de resistencia VanA (CIM90 512 μg/ml a vancomicina y CIM90 256 μg/ml a teicoplanina). El uso de vancomicina (p=0,02), la duración de la neutropenia mayor de 7 días (p=0,03) y la internación prolongada (media 42,8 días) (p=0,0001) fueron factores de riesgo asociados significativamente a la colonización con EVR. En función de estos resultados consideramos necesaria la vigilancia epidemiológica y la implementación de medidas de prevención y control. Vancomycin-resistant enterococci (VRE) have an important impact on pediatric oncology population. The objectives of this study were: to know the prevalence of VRE intestinal colonization in oncology patients, to identify the risk factors that predispose hospitalized patients to VRE intestinal colonization , and to determine the VRE resistance profile to different antimicrobial agents. We studied all children with oncological disease aged 1 month to 16 years that had joined the protocol and had been hospitalized from October 2006 to April 2007. VRE intestinal colonization was analyzed when the patient was admitted to hospital, 72 hours later, and weekly during hospitalization. A total of 333 samples were taken from 67 patients. From these, VRE were isolated in 12 patients, with a prevalence of 17.9%. Of the 28 isolates studied, taking one per patient, 10 were Enterococcus faecium and 2 Enterococcus faecalis, both with resistance phenotype VanA (CIM90 512 μg/ml to vancomycin and CIM90 256 μg/ml to teicoplanin). The use of vancomycin (p=0.02), duration of neutropen
Onset of the ridge structure in AA, pA and pp collisions
C. Andrés,A. Moscoso,C. Pajares
Physics , 2014, DOI: 10.1103/PhysRevC.90.054902
Abstract: It is shown that the anomalous sharp increasing of the strength of the near-side ridge structures observed in Au-Au collisions at $\sqrt{s}=$ 62 GeV and $\sqrt{s}=$ 200 GeV and the onset of the ridge structure in pPb and in pp collisions can be naturally explained in the framework of string percolation. In all the cases the near-side strength reflects the collision area covered by the strings stretched between the colliding objects and therefore it is related to the shape of their profile functions. The dependence of the pseudorapidty and azimuthal widths on multiplicty and energy is qualitatively explained.
Universal geometrical scaling for hadronic interactions
C. Andrés,A. Moscoso,C. Pajares
Physics , 2012, DOI: 10.1016/j.nuclphysa.2013.02.013
Abstract: It is shown that defining a suitable saturation momentum $Q_s$, the $p_T$ distributions of pp and AA collisions for any centrality and energy depend only on $\tau=p^2_T/Q_s^2$ for $p_T1$, the higher the energy or the larger the size of the participant nuclei, the larger suppression present the respective spectra. The integrated spectrum gives a fraction of the hard multiplicity in the range from 9% for pp at 0.9 TeV to 2% for Pb-Pb central collisions at 2.76 TeV.
Displasia arritmogénica del ventrículo derecho y enfermedad del nódulo sinusal
Balderramo,Domingo C.; Caeiro,Andrés A.;
Medicina (Buenos Aires) , 2004,
Abstract: arrhythmogenic right ventricular dysplasia (arvd) involves primarily the right ventricle, and should be considered in young patients presenting with syncope, ventricular tachycardia, cardiac arrest or in adults patients with congestive heart failure. atrial electrical abnormalities due to arvd have been rarely described. we report a case of arvd in a 60-year-old man who developed sick sinus syndrome during evolution (sinus node recovery time of 6113 mseg). atrial arrhythmias may be explained by gradual replacement of right atrium myocytes by adipose tissue.
Displasia arritmogénica del ventrículo derecho y enfermedad del nódulo sinusal Arrhythmogenic right ventricular dysplasia and sick sinus syndrome
Domingo C. Balderramo,Andrés A. Caeiro
Medicina (Buenos Aires) , 2004,
Abstract: La displasia arritmogénica del ventrículo derecho (DAVD) compromete principalmente al ventrículo derecho y debe ser considerada en pacientes jóvenes que presentan síncope, taquicardia ventricular o paro cardíaco y en adultos con insuficiencia cardíaca congestiva. Las alteraciones eléctricas auriculares debidas a DAVD han sido poco descriptas. Informamos el caso de un varón de 60 a os con DAVD que durante la evolución presentó enfermedad del nódulo sinusal (tiempo de recuperación del nódulo sinusal de 6113 mseg). Las arritmias auriculares se podrían explicar por el reemplazo gradual de los miocitos auriculares por tejido adiposo. Arrhythmogenic right ventricular dysplasia (ARVD) involves primarily the right ventricle, and should be considered in young patients presenting with syncope, ventricular tachycardia, cardiac arrest or in adults patients with congestive heart failure. Atrial electrical abnormalities due to ARVD have been rarely described. We report a case of ARVD in a 60-year-old man who developed sick sinus syndrome during evolution (sinus node recovery time of 6113 mseg). Atrial arrhythmias may be explained by gradual replacement of right atrium myocytes by adipose tissue.
Clinical and laboratory features of hepatocellular carcinoma
María C. Londo?o,Andrés Cárdenas
Iatreia , 2007,
Abstract: The clinical presentation of hepatocellular carcinoma (HCC) differs between patients in developing countries (African and Chinese populations) from those in industrialized countries. In industrialized countries, HCC co-exists with symptomatic cirrhosis in 80% of cases and clinical manifestations are usually related to those of the underlying disease. On the other hand, patients from developing countries have HCC and cirrhosis in approximately 40% of cases. Underlying cirrhosis in many cases is not advanced and does not produce any symptoms or associated symptoms are masked by those of the tumor (right upper quadrant pain, mass in the upper abdomen, weight loss and weakness). In a subset of patients, there are no clinical manifestations as HCC may occur in the context of hepatitis B infection without cirrhosis. Clinical Manifestations In Western countries, nearly 35% percent of patients with HCC are asymptomatic. Some of the most common clinical manifestations include: abdominal pain (53-58% of patients), especially in epigastrium or right upper quadrant, abdominal mass (30%), weight loss, malaise, anorexia, cachexia, jaundice or fever. Physical Exam Physical findings vary with the stage of disease. The patient may exhibit slight or moderate wasting when first seen. In patients with cirrhosis, typical stigmata of chronic liver disease may be present. In advanced stages of HCC the liver may be enlarged and there is significant tenderness. An arterial bruit may be heard over the liver. Jaundice is unusual at first presentation and, when present, is mild; it commonly appears or deepens with progression of the disease. A low to moderate, intermittent or remittent fever may be present. Unusual Presentations Obstructive jaundice: is the initial presentation in 1-12% of cases. It is due to compression of the major intrahepatic bile duct by the tumor, invasion of HCC into the lumen of intrahepatic bile ducts, infiltration of the wall of bile ducts causing obliteration of the lumen, hemobilia, or free-floating tumor plugs into the biliary tree. Acute abdomen: is a life-threatening complication caused by rupture of the tumor causing intraperito bleeding. It occurs in later stages of the tumor and is a frequent cause of death. Obstruction of splanchnic veins: tumor may invade the portal vein, hepatic veins and inferior vena cava, resulting in portal hypertension (with ascites and variceal bleeding), Budd-Chiari syndrome and pitting edema of lower limbs. Paraneop
Phylogeny of Bacteria from Steelmaking Wastes and Their Acidic Enrichment Cultures  [PDF]
Mariana P. Reis, Flaviane A. Pinheiro, Patrícia S. Costa, Ana Paula C. Salgado, Paulo S. Assis, Edmar Chartone-Souza, Andréa M. A. Nascimento
Advances in Microbiology (AiM) , 2014, DOI: 10.4236/aim.2014.412090
Abstract: Currently, millions of tons of steel are produced worldwide. This has become a serious economic and environmental challenge because the ores used for steel production are nonrenewable resources and the production generates huge amount of waste. In this study, we identified and investigated the ability of bacteria from steelmaking waste with low and high zinc concentration to promote leaching of zinc, when enriched by acidic (pH 2) culture conditions. The bioleaching assays indicated removal of Zn, as in chemical leaching. Bacterial communities from crude and enrichment culture wastes were characterized by the 16S rRNA gene. Phylogenetic analysis of the generated clone libraries revealed predominance of Proteobacteria and Firmicutes. The Actino- bacteria, Bacteroidetes, Cyanobacteria, and Deinococcus-Thermus phyla were also encountered. The clones were most closely related to cultivable heterotrophic bacteria. Different genera were identified including iron redox cycling and leaching bacteria such as Chromobacterium, Aeromonas, Escherichia, Bacillus, and Ochrobactrum. These data add significant new information on bacteria which survive in extremely acidic conditions. They are distantly related to typical acidophiles responsible for the leaching process, which makes them good candidates for future studies on metal bioleaching.
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