75 research outputs found

    Density dependence of resonance broadening and shadowing effects in nuclear photoabsorption

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    Medium effects as a function of the mass number AA are studied in the total photonuclear cross section from the Δ\Delta-resonance region up to the region where shadowing effects are known to exist. A consistent picture is obtained by simply assuming a density dependence of the different mechanisms of resonance broadening and shadowing. The Δ\Delta-mass shift is found to increase with AA.Comment: 7 pages, LaTeX, 2 figures available from the author

    Contraception: Influence on vaginal microbiota and identification of vaginal lactobacilli using MALDI-TOF MS and 16S rDNA sequencing

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    The vaginal microbiome is influenced by a wide variety of factors, including contraceptive methods. To evaluate the effect of contraceptive methods on vaginal microbiota and to compare MALDI-TOF MS and 16S rDNA sequencing for lactobacilli identification. Patients and Methods: One hundred and one (101) women consulting for birth control were included in a prospective study. Their vaginal content was sampled and analyzed once before they started using the contraceptive method of their choice, and twice after the initiation of contraception, at three months (94/101 women attended) and at six months (89/101 women attended). The relative frequencies of yeasts and trichomonas were analyzed. MALDI-TOF MS and 16S rDNA sequence analysis were applied for the identification of lactobacilli in their vaginal microbiota. The following contraceptive methods were assessed: Combined Oral Contraceptive Pill (COCP), Condom (CON) and The Rhythm Method (RHYT). McNemar's statistical test was applied. A statistically significant association between COCP and normal microbiota was observed after three months (p< 0.01) and after six months (p< 0.0001), when the vaginal microbiota was modified. At six months, inflammatory reaction was detected in 3/7 women in the CON group, while 6/7 patients using RHYT showed the same state. Yeast colonization increased with the COCP. Identification of lactobacilli by MALDI-TOF MS analysis compared to 16S rDNA sequencing yielded 92.9% concordant results. Lactobacillus gasseri and L. crispatus were the predominant species. The pattern of vaginal states was significantly modified. Hormone administration apparently corrected the alterations and retained a normal vaginal state. MALDI-TOF MS has the potential of being an accurate tool for the identification of vaginal lactobacilli species L. murinus was for the first time isolated from the vagina.Fil: Fosch, Sonia E.. Ministerio de Salud; Argentina. Fundación Bioquímica Argentina; ArgentinaFil: Aristimuño Ficoseco, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumån. Centro de Referencia para Lactobacilos; ArgentinaFil: Marchesi, Antonella. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumån. Centro de Referencia para Lactobacilos; ArgentinaFil: Cocucci, Silvina Ema. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Nader, Maria Elena Fatima. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumån. Centro de Referencia para Lactobacilos; Argentina. Universidad del Norte Santo Tomås de Aquino; ArgentinaFil: Perazzi, Beatriz Elizabeth. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; Argentin

    Clinical Performance of Two Methods for Detecting Anti SARS-CoV-2 Antibodies

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    Evaluating the clinical performance of available methods to detect antibodies against Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has become a primordial issue in clinical laboratories. The aim of this study was to evaluate the clinical performance of two methods for SARS-CoV-2 antibodies detection, an automated Chemiluminescent Immunoassay (CLIA) and an immunochromatographic Lateral-Flow Assay (LFA) in patients with positive reverse transcription polymerase chain reaction (RT-PCR). Performance for CLIA method was Positive Agreement (PA) 56.6% and Negative Agreement (NA) 96,6% for IgM and PA 85.8%/NA 90,2% for IgG. Performance for LFA method was PA 56.2% and NA 100% for IgM and PA 95.5% and NA 100 % for IgG. LFA general agreement IgG was better than CLIA. In both methods, significant differences in Kappa index are observed when IgG and IgM are compared. When evaluating the data from a clinical perspective, we found that both method performance for IgM detection may not meet the expected requirements for their clinical utility and could lead to an inappropriate medical decision. The findings of this study show that both immunoassay methods might be reliable for assessing immunological response in COVID-19 patients. Our results also confirm that IgG measurement could be helpful, especially for epidemiological studies in our population. These results provide evidence to justify epidemiological studies in our population.Fil: Jacobsen, Dario Gustavo. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂ­mica. Departamento de BioquĂ­mica ClĂ­nica; ArgentinaFil: Gonzalez, D.. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂ­mica. Departamento de BioquĂ­mica ClĂ­nica; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂ­mica. Instituto de FisiopatologĂ­a y BioquĂ­mica ClĂ­nica; ArgentinaFil: Jamardo, J.. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂ­mica. Departamento de BioquĂ­mica ClĂ­nica; ArgentinaFil: Ibar, C.. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂ­mica. Departamento de BioquĂ­mica ClĂ­nica; ArgentinaFil: Pugliese, L.. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂ­mica. Departamento de BioquĂ­mica ClĂ­nica; ArgentinaFil: Fortuna, F.. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂ­mica. Departamento de BioquĂ­mica ClĂ­nica; ArgentinaFil: Carrizo, E.. Coordinadora de Salud Misionar; ArgentinaFil: Caro, E. M.. Laboratorio Biogenar; ArgentinaFil: Perazzi, Beatriz Elizabeth. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂ­mica. Departamento de BioquĂ­mica ClĂ­nica; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂ­mica. Instituto de FisiopatologĂ­a y BioquĂ­mica ClĂ­nica; ArgentinaFil: Repetto, Esteban MartĂ­n. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂ­mica. Departamento de BioquĂ­mica ClĂ­nica; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; ArgentinaFil: Reboredo, G.. Universidad de Buenos Aires. Facultad de Medicina. Hospital de ClĂ­nicas General San MartĂ­n; ArgentinaFil: Fabre, B.. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂ­mica. Departamento de BioquĂ­mica ClĂ­nica; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂ­mica. Instituto de FisiopatologĂ­a y BioquĂ­mica ClĂ­nica; Argentin

    Goldstino and sgoldstino in microscopic models and the constrained superfields formalism

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    We examine the exact relation between the superconformal symmetry breaking chiral superfield (X) and the goldstino superfield in microscopic models of an arbitrary Kahler potential (K) and in the presence of matter fields. We investigate the decoupling of the massive sgoldstino and scalar matter fields and the offshell/onshell-SUSY expressions of their superfields in terms of the fermions composites. For general K of two superfields, we study the properties of the superfield X after integrating out these scalar fields, to show that in the infrared it satisfies (offshell) the condition X3=0X^3=0 and X2=Ìž0X^2\not=0. We then compare our results to those of the well-known method of constrained superfields discussed in the literature, based on the conjecture X2=0X^2=0. Our results can be used in applications, to couple offshell the (s)goldstino fields to realistic models such as the MSSM.Comment: 24 page

    Yukawa Deflected Gauge Mediation in Four Dimensions

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    We construct a four dimensional realization of a higher dimensional model, Yukawa deflected gauge mediation, in which supersymmetry breaking is communicated to the visible sector through both gauge and Yukawa interactions. The reduction to four dimensions is achieved by `deconstructing' or `latticizing' the extra dimension. Three sites (gauge groups) are sufficient to reproduce the spectrum of the higher dimensional model. The characteristic features of Yukawa deflected gauge mediation, in particular, alignment of squarks and quarks, and a natural solution to the mu problem, carry over to the deconstructed version of the model. We comment on the implications of our results for a solution of the mu problem in the context of deconstructed gaugino mediation.Comment: 11 pages, 1figur

    Allogeneic mesenchymal stem cells improve the wound healing process of sheep skin

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    Abstract Background Skin wound healing includes a system of biological processes, collectively restoring the integrity of the skin after injury. Healing by second intention refers to repair of large and deep wounds where the tissue edges cannot be approximated and substantial scarring is often observed. The objective of this study was to evaluate the effects of mesenchymal stem cells (MSCs) in second intention healing using a surgical wound model in sheep. MSCs are known to contribute to the inflammatory, proliferative, and remodeling phases of the skin regeneration process in rodent models, but data are lacking for large animal models. This study used three different approaches (clinical, histopathological, and molecular analysis) to assess the putative action of allogeneic MSCs at 15 and 42 days after lesion creation. Results At 15 days post-lesion, the wounds treated with MSCs showed a higher degree of wound closure, a higher percentage of re-epithelialization, proliferation, neovascularization and increased contraction in comparison to a control group. At 42 days, the wounds treated with MSCs had more mature and denser cutaneous adnexa compared to the control group. The MSCs-treated group showed an absence of inflammation and expression of CD3+ and CD20+. Moreover, the mRNA expression of hair-keratine (hKER) was observed in the MSCs-treated group 15 days after wound creation and had increased significantly by 42 days post-wound creation. Collagen1 gene (Col1α1) expression was also greater in the MSCs-treated group compared to the control group at both days 15 and 42. Conclusion Peripheral blood-derived MSCs may improve the quality of wound healing both for superficial injuries and deep lesions. MSCs did not induce an inflammatory response and accelerated the appearance of granulation tissue, neovascularization, structural proteins, and skin adnexa

    Extra Dimensions at the Weak Scale and Deviations from Newtonian Gravity

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    We consider theories in which the Standard Model gauge fields propagate in extra dimensions whose size is around the electroweak scale. The Standard Model quarks and leptons may either be localized to a brane or propagate in the bulk. This class of theories includes models of Scherk-Schwarz supersymmetry breaking and universal extra dimensions. We consider the problem of stabilizing the volume of the extra dimensions. We find that for a large class of stabilization mechanisms the field which corresponds to fluctuations of the volume remains light even after stabilization, and has a mass in the 10−310^{-3} eV range. In particular this is the case if stabilization does not involve dynamics at scales larger than the cutoff of the higher dimensional Standard Model, and if the effective theory below the compactification scale is four dimensional. The mass of this field is protected against large radiative corrections by the general covariance of the higher dimensional theory and by the weakness of its couplings, which are Planck suppressed. Its couplings to matter mediate forces whose strength is comparable to that of gravity and which can give rise to potentially observable deviations from Newton's Law at sub-millimeter distances. Current experiments investigating short distance gravity can probe extra dimensions too small to be accessible to current collider experiments. In particular for a single extra dimension stabilized by the Casimir energy of the Standard Model fields compactification radii as small as 5 inverse TeV are accessible to current sub-millimeter gravity experiments.Comment: Minor corrections, conclusions unchanged. References adde

    Radiative decays of decuplet hyperons

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    We calculate the radiative decay widths of decuplet hyperons in a chiral constituent quark model including electromagnetic exchange currents between quarks. Exchange currents contribute significantly to the E2 transition amplitude, while they largely cancel for the M1 transition amplitude. Strangeness suppression of the radiative hyperon decays is found to be weakened by exchange currents. Differences and similarities between our results and other recent model predictions are discussed.Comment: 11 pages, 1 eps figure, revtex, accepted for publication in Phys. Rev.

    Efficacy of conventional versus innovative therapies for treating skin wounds in veterinary medicine

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    open16siINTRODUCTION: The skin is the largest organ of mammals. The loss of skin integrity may induce important dysfunctions or even death. For superficial wounds, the endogenous healing mechanisms in combination with traditional wound care are sufficient to achieve functional repair. In contrast, in larger wounds, like third and fourth degree burns, chronic wound or deep ulcers it is difficult to obtain the restitutio ad integrum and fibrosis and/or scar tissue develops1,2. The aim of this study was to verify the efficacy of conventional and innovative topic treatments on skin regeneration, induced experimentally in sheep. To achieve this goal different types of investigations (clinical, molecular, histological, immunohistochemical) were performed. METHODS: Six skin lesions (4x4cm) were surgically created on the back of six healthy adult sheep; every single wound was destined, in a randomized way, to one of the following treatments: Acemannan gel, Manuka Honey, hyaluronic acid, Plasma3 (ionized gas), allogeneic mesenchymal stem cells isolated from peripheral blood (PB-MSCs). The sixth wound was the placebo. Biopsies were collected with a surgical punch (0,6x0,6 cm) at time T0, T15 and T40 days. Lesions were clinically evaluated considering the presence and color of wound fluid, the state of hydration, the wound surface/surroundings and other parameters. Histological examinations considered crust formation, re-epithelization and epidermal thickness, dermis edema, extension of granulation tissue, acute and chronic inflammation. Immunohistochemistry for evaluation of inflammation, vascularization and cell proliferation was performed using CD3, CD20, MHCII, von Willebrand factor (vWF) and KI67 antibodies. Furthermore, Real time-PCR investigated genes as V ascular endothelial growth factors (VEGF), Transforming growth factor beta 1(TGFÎČ1), Vimentin (VIM), Collagen 1α1 (Col1α1) and hair Keratin (hKER). RESULTS: Clinically, the lesions treated with plasma healed more rapidly respect to other treatments and a reduced bacterial load was observed. At T7 wounds treated with stem cells and plasma were less macerated than lesions treated with other therapies. At T15 the wounds treated with hyaluronic acid showed a normal state of hydration while lesions treated with Manuka Honey exhibited a normal hydration from the third week only (Acemannan gel at fourth week). From the second week onwards all wounds did not show presence of fluid and exhibited a dry and clean secondary layer. All lesions, excluded wounds treated with acemannan gel, presented a red (hyaluronic acid and plasma) and dark red (Manuka Honey, PB-MSCs) granulation tissue starting from the first week. Molecular analysis showed a correspondence between clinical and molecular/histologic results. For instance, VEGF mRNA expression confirms angiogenetic events observed at histological level while TGF-ÎČ, CD3 and CD20 mRNA/protein expression indicated the presence/absence of inflammation in the used treatments. DISCUSSION & CONCLUSIONS: Innovative therapies led to surprising results regarding regeneration of mammalian skin. Indeed, on the basis of clinical analysis, wounds treated with plasma and MSC healed more rapidly. Further examinations are ongoing in order to elucidate possible mechanisms explaining these differences. REFERENCES: 1S.Y. Broeckx, S. Maes, T. Martinello, et al (2014) Equine epidermis: a source of epithelial-like stem/progenitor cells with in vitro and in vivo regenerative capacities Stem Cells Dev, pp 1134-48. 2J.H. Spaas, C. Gomiero, S.Y. Broeckx, et al (2016) Wound healing markers after autologous and allogeneic epithelial-like stem cell treatment Cytotherapy 2016 (in press). 3E. Martines, M. Zuin, R. Cavazzana, et al. (2009) A novel plasma source for sterilization of living tissues, New J. Phys. 11, 115014.openPatruno, MARCO VINCENZO; Gomiero, Chiara; Martinello, Tiziana; Perazzi, Anna; Gemignani, F; DE BENEDICTIS, GIULIA MARIA; Ferro, Silvia; Zuin, M; Martines, E; Cordaro, Luigi; Brun, Paola; Maccatrozzo, Lisa; Broeckx, Sy; Spaas, Jh; Chiers, K; Iacopetti, IlariaPatruno, MARCO VINCENZO; Gomiero, Chiara; Martinello, Tiziana; Perazzi, Anna; Gemignani, F; DE BENEDICTIS, GIULIA MARIA; Ferro, Silvia; Zuin, M; Martines, E; Cordaro, Luigi; Brun, Paola; Maccatrozzo, Lisa; Broeckx, Sy; Spaas, Jh; Chiers, K; Iacopetti, Ilari
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