784 research outputs found
Caracterización funcional y estructural del biofilm epipélico en relación al aumento de la urbanización en un arroyo de la Llanura Pampeana (Argentina)
Fil: Sierra, María Victoria. Instituto de Limnología Dr. Raúl A. Ringuelet (ILPLA). Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Gómez, Nora. Instituto de Limnología Dr. Raúl A. Ringuelet (ILPLA). Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Marano, Agostina Virginia. División Instituto Spegazzini. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Di Siervi, Miguel A.. Instituto de Limnología Dr. Raúl A. Ringuelet (ILPLA). Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; Argentin
Antibiotic resistance and integrons in Shiga toxin-producing Escherichia coli (STEC)
Shiga toxin-producing Escherichia coli (STEC) cause hemorrhagic colitis (HC) and hemolyticuremic syndrome in humans (HUS). Cattle are the main reservoir of STEC and transmission to humans occurs through contaminated food and water. Antibiotics are used in pig production systems to combat disease and improve productivity and play a key role in the dissemination of antibiotic resistance genes to the bacteria. Integrons have been identified in resistant bacteria allowing for the acquisition and dissemination of antibiotic resistance genes. STEC strains isolated from humans and animals have developed antibiotic resistance. In our laboratory, 21 non-157 STEC strains isolated from pigs were analyzed to detect class 1 and 2 integrons by PCR. Eight carried integrons, 7 of them harbored intl2. In another study 545 STEC strains were also analyzed for the presence of intl1 and intl2. Strains carrying intl1 belonged to isolates from environment (n = 1), chicken hamburger (n = 2), dairy calves (n = 4) and pigs (n = 8). Two strains isolated from pigs harbored intl2 and only one intl1/intl2, highlighting the presence of intl2 in pigs. The selection for multiresistant strains may contribute to the emergence of antibiotic resistant pathogens and facilitate the spreading of the mobile resistance elements to other bacteria
Effectiveness of high-intensity interval training for weight loss in adults with obesity: A randomised controlled non-inferiority trial
Introduction Obesity treatment guidelines suggest moderate-intensity continuous training (MICT), but the patient's compliance to this indication remains low. High-intensity interval training (HIIT) is a time sparing training mode whose metabolic effects are not clear. This study aimed to determine whether a 12-week HIIT was more effective than MICT for weight loss in obese adults. Methods 44 obese subjects were randomised and trained with isoenergetic treadmill exercises for 12 weeks: MICT (60% of maximal oxygen peak, VO 2 peak) or HIIT (3-7 repetition of 3 min 100% of VO 2 peak interspersed by 1.5 min 50% of VO 2 peak). The primary outcome was a change in body weight; the secondary outcomes were changes in body composition, blood pressure, lipid profile, glycaemia, insulin and VO 2 peak. Results 32 subjects (53% male, mean age: 38.5 years, mean body mass index: 35.5 kg/m 2) completed the trial. MICT and HIIT showed comparable effect within groups in weight loss (-6.0 kg (-9.0 kg to -3.0 kg) vs -5.7 kg (-8.3 kg to -3.1 kg)), changes in fat mass (-2.9% (-4.4% to -1.4%) vs -3.6% (-5.9% to -1.2%)), fat free mass (-5.3% (-7.8% to -2.8%) vs -5.5% (-8.3% to -2.6%)), diastolic blood pressure (-5.5 mm Hg (-10.6 mm Hg to -0.3 mm Hg) vs -5.8 mm Hg (-11.3 mm Hg to -0.3 mm Hg)) and low-density lipoprotein cholesterol (-16.4 mg/dL (-30.8 mg/dL to -2.0 mg/dL) vs -14.7 mg/dL (-25.6 mg/dL to -3.8 mg/dL)). There was a significant change between groups in VO 2 peak (HIIT: +461.6 mL (329.3a \u20ac'593.8 mL); MICT: +170.5 mL (86.7-254.4 mL); p<0001) and duration of sessions (HIIT: 35.0 min (31.7 a \u20ac'35.6 min); MICT: 46.5 min (40.2a \u20ac'48.3 min); p<0.001). No significant changes in systolic blood pressure, high-density lipoprotein cholesterol, triglycerides, glycaemia or plasma insulin were observed. Conclusions In healthy adults with obesity, HIIT compared with MICT induced similar weight loss and cardiovascular risk factors improvement but resulted in a larger increase in cardiorespiratory fitness over a shorter period
From the Feynman-Schwinger representation to the non-perturbative relativistic bound state interaction
We write the 4-point Green function in QCD in the Feynman-Schwinger
representation and show that all the dynamical information are contained in the
Wilson loop average. We work out the QED case in order to obtain the usual
Bethe-Salpeter kernel. Finally we discuss the QCD case in the non-perturbative
regime giving some insight in the nature of the interaction kernel.Comment: 25 pages, RevTex, 3 figures included, typos corrected, to appear in
Phys. Rev. D 5
Chromosomal plasticity and evolutionary potential in the malaria vector Anopheles gambiae sensu stricto: insights from three decades of rare paracentric inversions
Background: In the Anopheles gambiae complex, paracentric chromosomal inversions are nonrandomly distributed along the complement: 18/31 (58%) of common polymorphic inversions are on chromosome arm 2R, which represents only ~30% of the complement. Moreover, in An.gambiae sensu stricto, 6/7 common polymorphic inversions occur on 2R. Most of these inversions are considered markers of ecological adaptation that increase the fitness of the carriers of alternative karyotypes in contrasting habitats. However, little is known about the evolutionary forces responsible for their origin and subsequent establishment in field populations. Results: Here, we present data on 82 previously undescribed rare chromosomal inversions (RCIs) recorded during extensive field sampling in 16 African countries over a 30 year period, which may shed light on the dynamics of chromosomal plasticity in An. gambiae. We analyzed breakpoint distribution, length, and geographic distribution of RCIs, and compared these measures to those of the common inversions. We found that RCIs, like common inversions, are disproportionately clustered on 2R, which may indicate that this arm is especially prone to breakages. However, contrasting patterns were observed between the geographic distribution of common inversions and RCIs. RCIs were equally frequent across biomes and on both sides of the Great Rift Valley (GRV), whereas common inversions predominated in arid ecological settings and west of the GRV. Moreover, the distribution of RCI lengths followed a random pattern while common inversions were significantly less frequent at shorter lengths. Conclusion: Because 17/82 (21%) RCIs were found repeatedly at very low frequencies – at the same sampling location in different years and/or in different sampling locations – we suggest that BMC Evolutionary Biology 2008, 8:309 http://www.biomedcentral.com/1471-2148/8/309 RCIs are subject mainly to drift under unperturbed ecological conditions. Nevertheless, RCIs may represent an important reservoir of genetic variation for An. gambiae in response to environmental changes, further testifying to the considerable evolutionary potential hidden within this pan-African malaria vector
An In Vivo Screen Identifies PYGO2 as a Driver for Metastatic Prostate Cancer
Advanced prostate cancer displays conspicuous chromosomal instability and rampant copy number aberrations, yet the identity of functional drivers resident in many amplicons remain elusive. Here, we implemented a functional genomics approach to identify new oncogenes involved in prostate cancer progression. Through integrated analyses of focal amplicons in large prostate cancer genomic and transcriptomic datasets as well as genes upregulated in metastasis, 276 putative oncogenes were enlisted into an in vivo gain-of-function tumorigenesis screen. Among the top positive hits, we conducted an in-depth functional analysis on Pygopus family PHD finger 2 (PYGO2), located in the amplicon at 1q21.3. PYGO2 overexpression enhances primary tumor growth and local invasion to draining lymph nodes. Conversely, PYGO2 depletion inhibits prostate cancer cell invasion in vitro and progression of primary tumor and metastasis in vivo In clinical samples, PYGO2 upregulation associated with higher Gleason score and metastasis to lymph nodes and bone. Silencing PYGO2 expression in patient-derived xenograft models impairs tumor progression. Finally, PYGO2 is necessary to enhance the transcriptional activation in response to ligand-induced Wnt/β-catenin signaling. Together, our results indicate that PYGO2 functions as a driver oncogene in the 1q21.3 amplicon and may serve as a potential prognostic biomarker and therapeutic target for metastatic prostate cancer.Significance: Amplification/overexpression of PYGO2 may serve as a biomarker for prostate cancer progression and metastasis. Cancer Res; 78(14); 3823-33. ©2018 AACR
Partial growth hormone insensitivity and dysregulatory immune disease associated with de novo germline activating STAT3 mutations
Germinal heterozygous activating STAT3 mutations represent a novel monogenic defect associated with multi-organ autoimmune disease and, in some cases, severe growth retardation. By using whole-exome sequencing, we identified two novel STAT3 mutations, p.E616del and p.C426R, in two unrelated pediatric patients with IGF-I deficiency and immune dysregulation. The functional analyses showed that both variants were gain-of-function (GOF), although they were not constitutively phosphorylated. They presented differences in their dephosphorylation kinetics and transcriptional activities under interleukin-6 stimulation. Both variants increased their transcriptional activities in response to growth hormone (GH) treatment. Nonetheless, STAT5b transcriptional activity was diminished in the presence of STAT3 GOF variants, suggesting a disruptive role of STAT3 GOF variants in the GH signaling pathway. This study highlights the broad clinical spectrum of patients presenting activating STAT3 mutations and explores the underlying molecular pathway responsible for this condition, suggesting that different mutations may drive increased activity by slightly different mechanisms.Fil: Gutiérrez, Mariana Lilián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Scaglia, Paula Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Keselman, Ana Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Martucci, Lucia Camila. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Karabatas, Liliana Margarita. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Domene, Sabina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Martin, Ayelen. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Pennisi, Patricia Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Blanco, Miguel. Hospital Universitario Austral; ArgentinaFil: Sanguineti, Nora María. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Bezrodnik, Liliana. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez". Area de Inmunología. Grupo de Inmunología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Di Giovanni, Daniela. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez". Area de Inmunología. Grupo de Inmunología; ArgentinaFil: Caldirola, Maria Soledad. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez". Area de Inmunología. Grupo de Inmunología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Esnaola Azcoiti, María. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez". Area de Inmunología. Grupo de Inmunología; ArgentinaFil: Gaillard, María Isabel. Cincinnati Children's Hospital Medical Center; Estados UnidosFil: Denson, Lee A.. Cincinnati Children's Hospital Medical Center; Estados UnidosFil: Zhang, Kejian. Cincinnati Children's Hospital Medical Center; Estados UnidosFil: Husami, Ammar. Cincinnati Children's Hospital Medical Center; Estados UnidosFil: Yayah Jones, Nana Hawa. Cincinnati Children's Hospital Medical Center; Estados UnidosFil: Hwa, Vivian. Cincinnati Children's Hospital Medical Center; Estados UnidosFil: Revale, Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Agrobiotecnología de Rosario; ArgentinaFil: Vazquez, Martin Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Agrobiotecnología de Rosario; ArgentinaFil: Jasper, Hector Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Kumar, Ashish. Cincinnati Children's Hospital Medical Center; Estados UnidosFil: Domene, Horacio Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; Argentin
Inclusive Decays of Heavy Quarkonium to Light Particles
We derive the imaginary part of the potential NRQCD Hamiltonian up to order
1/m^4, when the typical momentum transfer between the heavy quarks is of the
order of Lambda_{QCD} or greater, and the binding energy E much smaller than
Lambda_{QCD}. We use this result to calculate the inclusive decay widths into
light hadrons, photons and lepton pairs, up to O(mv^3 x
(Lambda_{QCD}^2/m^2,E/m)) and O(mv^5) times a short-distance coefficient, for
S- and P-wave heavy quarkonium states, respectively. We achieve a large
reduction in the number of unknown non-perturbative parameters and, therefore,
we obtain new model-independent QCD predictions. All the NRQCD matrix elements
relevant to that order are expressed in terms of the wave functions at the
origin and six universal non-perturbative parameters. The wave-function
dependence factorizes and drops out in the ratio of hadronic and
electromagnetic decay widths. The universal non-perturbative parameters are
expressed in terms of gluonic field-strength correlators, which may be fixed by
experimental data or, alternatively, by lattice simulations. Our expressions
are expected to hold for most of the charmonium and bottomonium states below
threshold. The calculations and methodology are explained in detail so that the
evaluation of higher order NRQCD matrix elements in this framework should be
straightforward. An example is provided.Comment: 61 pages, 9 figures. Minor change
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