214 research outputs found
High scale impact in alignment and decoupling in two-Higgs doublet models
The two-Higgs doublet model (2HDM) provides an excellent benchmark to study
physics beyond the Standard Model (SM). In this work we discuss how the
behaviour of the model at high energy scales causes it to have a scalar with
properties very similar to those of the SM -- which means the 2HDM can be seen
to naturally favor a decoupling or alignment limit. For a type II 2HDM, we show
that requiring the model to be theoretically valid up to a scale of 1 TeV, by
studying the renormalization group equations (RGE) of the parameters of the
model, causes a significant reduction in the allowed magnitude of the quartic
couplings. This, combined with -physics bounds, forces the model to be
naturally decoupled. As a consequence, any non-decoupling limits in type II,
like the wrong-sign scenario, are excluded. On the contrary, even with the very
constraining limits for the Higgs couplings from the LHC, the type I model can
deviate substantially from alignment. An RGE analysis similar to that made for
type II shows, however, that requiring a single scalar to be heavier than about
500 GeV would be sufficient for the model to be decoupled. Finally, we show
that not only a 2HDM where the lightest of the CP-even scalars is the 125 GeV
one does not require new physics to be stable up to the Planck scale but this
is also true when the heavy CP-even Higgs is the 125 GeV and the theory has no
decoupling limit for the type I model.Comment: 28 pages, 19 figure
Struttura familiare e comportamenti devianti dei giovani in Italia: uno studio effettuato attraverso il metodo del self-report
Pediatric lymphomas in Brazil
OBJECTIVE: This study provides the clinical pathological characteristics of 1301 cases of pediatric/adolescent lymphomas in patients from different geographic regions of Brazil. METHODS: A retrospective analyses of diagnosed pediatric lymphoma cases in a 10-year period was performed. We believe that it represents the largest series of pediatric lymphomas presented from Brazil. RESULTS: Non-Hodgkin lymphomas represented 68% of the cases, including those of precursor (36%) and mature (64%) cell origin. Mature cell lymphomas comprised 81% of the B-cell phenotype and 19% of the T-cell phenotype. Hodgkin lymphomas represented 32% of all cases, including 87% of the classical type and 13% of nodular lymphocyte predominant type. The geographic distribution showed 38.4% of the cases in the Southeast region, 28.7% in the Northeast, 16.1% in the South, 8.8% in the North, and 8% in the Central-west region. The distribution by age groups was 15-18 years old, 33%; 11-14 years old, 26%; 6-10 years old, 24%; and 6 years old or younger, 17%. Among mature B-cell lymphomas, most of the cases were Burkitt lymphomas (65%), followed by diffuse large B-cell lymphomas (24%). In the mature T-cell group, anaplastic large cell lymphoma, ALK-positive was the most prevalent (57%), followed by peripheral T-cell lymphoma, then not otherwise specified (25%). In the group of classic Hodgkin lymphomas, the main histological subtype was nodular sclerosis (76%). Nodular lymphocyte predominance occurred more frequently than in other series. CONCLUSION: Some of the results found in this study may reflect the heterogeneous socioeconomical status and environmental factors of the Brazilian population in different regions
Personaggi scientifici e personaggi letterari:la delinquente di Lombroso, la Norma di Bellini e l’influsso reciproco fra cultura di massa ed elaborazione scientifica
HPV infection and immunochemical detection of cell-cycle markers in verrucous carcinoma of the penis
Penile verrucous carcinoma is a rare disease and little is known of its aetiology or pathogenesis. In this study we examined cell-cycle proteins expression and correlation with human papillomavirus infection in a series of 15 pure penile verrucous carcinomas from a single centre. Of 148 penile tumours, 15 (10%) were diagnosed as pure verrucous carcinomas. The expression of the cell-cycle-associated proteins p53, p21, RB, p16INK4A and Ki67 were examined by immunohistochemistry. Human papillomavirus infection was determined by polymerase chain reaction to identify a wide range of virus types. The expression of p16INK4A and Ki67 was significantly lower in verrucous carcinoma than in usual type squamous cell carcinoma, whereas the expression of p53, p21 and RB was not significantly different. p53 showed basal expression in contrast to usual type squamous cell carcinoma. Human papillomavirus infection was present in only 3 out of 13 verrucous carcinomas. Unique low-risk, high-risk and mixed viral infections were observed in each of the three cases. In conclusion, lower levels of p16INK4A and Ki67 expressions differentiate penile verrucous carcinoma from usual type squamous cell carcinoma. The low Ki67 index reflects the slow-growing nature of verrucous tumours. The low level of p16INK4A expression and human papillomavirus detection suggests that penile verrucous carcinoma pathogenesis is unrelated to human papillomavirus infection and the oncogenes and tumour suppressor genes classically altered by virus infection.Peer reviewedFinal Accepted Versio
Burkitt Lymphoma in Brazil Is Characterized by Geographically Distinct Clinicopathologic Features
Burkitt lymphoma (BL) is a highly aggressive non-Hodgkin lymphoma with a consistent MYC translocation. Epstein-Barr virus (EBV) has been associated with BL at different frequencies, depending on the clinical variant and geographic regions. This is a large-scale study of BL in Brazil, including 234 patients from 5 geographic regions that are widely disparate socioeconomically, including pediatric (61.1%) and adult (37.6%) populations. EBV was present in 52.6% of all BL cases, varying from 29% (12/42) in the South to 76% (13/17) in the North. Most of the cases were EBV type A. The frequency was higher in the pediatric group, and EBV association within this age range predominated in all regions except the South. Expression of p53 protein was observed in 16.2%, and only rare cases showed p63 expression. BL in Brazil is regionally distinct and has a low incidence of p53 overexpression and a higher-than-expected association with EBV in sporadic cases
Primary hyperparathyroidism diagnosed after surgical ablation of a costal mass mistaken for giant-cell bone tumor: a case report
<p>Abstract</p> <p>Introduction</p> <p>Primary hyperparathyroidism is a common endocrine disorder characterized by elevated parathyroid hormone levels, which cause continuous osteoclastic bone resorption. Giant cell tumor of bone is an expansile osteolytic tumor that contains numerous osteoclast-like giant cells. There are many similarities in the radiological and histological features of giant cell tumor of bone and brown tumor. This is a rare benign focal osteolytic process most commonly caused by hyperparathyroidism.</p> <p>Case presentation</p> <p>We report the unusual case of a 40-year-old Caucasian woman in which primary hyperparathyroidism was diagnosed after surgical ablation of a costal mass. The mass was suspected of being neoplastic and histopathology was compatible with a giant cell tumor of bone. On the basis of the biochemical results (including serum calcium, phosphorous and intact parathyroid hormone levels) primary hyperparathyroidism was suspected and a brown tumor secondary to refractory hyperparathyroidism was diagnosed.</p> <p>Conclusions</p> <p>Since giant cell tumor is a bone neoplasm that has major implications for the patient, the standard laboratory tests in patients with bone lesions are important for a correct diagnosis.</p
Aberrant antigenic expression in extranodal NK/T-cell lymphoma: a multi-parameter study from Thailand
<p>Abstract</p> <p>Background</p> <p>Extranodal NK/T-cell lymphoma, nasal type (ENKTL) is not common worldwide, but it is the most common T- and NK-cell lymphomas in many Asian countries. Immunophenotypic profiles were studied based on limited series. The authors, therefore, studied on ENKTL according to characterize immunophenotypic profiles as well as the distribution of EBV subtype and LMP-1 gene deletion.</p> <p>Methods</p> <p>By using tissue microarray (TMA), immunohistochemical study and EBV encoded RNA (EBER) in situ hybridization were performed. T-cell receptor (TCR) gene rearrangement, EBV subtyping, and LMP-1 gene deletion were studied on the available cases.</p> <p>Results</p> <p>There were 22 cases eligible for TMA. ENKTL were positive for CD3 (91%), CD5 (9%), CD7 (32%), CD4 (14%), CD56 (82%), TIA-1 (100%), granzyme B (95%), perforin (86%), CD45 (83%), CD30 (75%), Oct2 (25%), and IRF4/MUM1 (33%). None of them was positive for ÎČF1, CD8, or CD57. TCR gene rearrangement was negative in all 18 tested cases. EBV was subtype A in all 15 tested cases, with 87% deleted LMP-1 gene. Cases lacking perforin expression demonstrated a significantly poorer survival outcome (p = 0.008).</p> <p>Conclusions</p> <p>The present study demonstrated TIA-1 and EBER as the two most sensitive markers. There were a few CD3 and/or CD56 negative cases noted. Interestingly, losses of CD45 and/or CD7 were not uncommon while Oct2 and IRF4/MUM1 could be positive in a subset of cases. Based on the present study in conjunction with the literature review, determination of PCR-based TCR gene rearrangement analysis might not be a useful technique for making diagnosis of ENKTL.</p
On the general theory of the origins of retroviruses
<p>Abstract</p> <p>Background</p> <p>The order retroviridae comprises viruses based on ribonucleic acids (RNA). Some, such as HIV and HTLV, are human pathogens. Newly emerged human retroviruses have zoonotic origins. As far as has been established, both repeated infections (themselves possibly responsible for the evolution of viral mutations <b>(Vm) </b>and host adaptability <b>(Ha)</b>); along with interplay between <it>inhibitors </it>and <it>promoters </it>of cell tropism, are needed to effect retroviral cross-species transmissions. However, the exact <it>modus operadi </it>of intertwine between these factors at molecular level remains to be established. Knowledge of such intertwine could lead to a better understanding of retrovirology and possibly other infectious processes. This study was conducted to derive the mathematical equation of a general theory of the origins of retroviruses.</p> <p>Methods and results</p> <p>On the basis of an arbitrarily non-Euclidian geometrical "thought experiment" involving the cross-species transmission of simian foamy virus (sfv) from a non-primate species <it>Xy </it>to <it>Homo sapiens </it>(<it>Hs</it>), initially excluding all social factors, the following was derived. At the port of exit from <it>Xy </it>(where the species barrier, SB, is defined by the <it>Index of Origin</it>, IO), sfv shedding is (1) enhanced by two transmitting tensors <b>(Tt)</b>, (i) virus-specific immunity (VSI) and (ii) evolutionary defenses such as APOBEC, RNA interference pathways, and (when present) expedited therapeutics (denoted e<sup>2</sup>D); and (2) opposed by the five accepting scalars <b>(At)</b>: (a) genomic integration hot spots, gIHS, (b) nuclear envelope transit <b>(</b>NMt) vectors, (c) virus-specific cellular biochemistry, VSCB, (d) virus-specific cellular receptor repertoire, VSCR, and (e) pH-mediated cell membrane transit, (â<sub>pH </sub>CMat). Assuming <b>As </b>and <b>Tt </b>to be independent variables, <b>IO = Tt/As</b>. The same forces acting in an opposing manner determine SB at the port of sfv entry (defined here by the <it>Index of Entry</it>, <b>IE = As/Tt</b>). Overall, If sfv encounters no unforeseen effects on transit between X<it>y </it>and <it>Hs</it>, then the square root of the combined index of sfv transmissibility (â<b>|RTI|) </b>is proportional to the product IO* IE (or ~Vm* Ha* âTt*âAs*<b>Ω</b>), where <b>Ω </b>is the retrovirological constant and â is a function of the ratio Tt/As or As/Tt for sfv transmission from <it>Xy </it>to <it>Hs</it>.</p> <p>Conclusions</p> <p>I present a mathematical formalism encapsulating the general theory of the origins of retroviruses. It summarizes the choreography for the intertwined interplay of factors influencing the probability of retroviral cross-species transmission: <b>Vm, Ha, Tt, As, </b>and <b>Ω</b>.</p
Association of interferon regulatory factor 4 gene polymorphisms rs12203592 and rs872071 with skin cancer and haematological malignancies susceptibility: a meta-analysis of 19 caseâcontrol studies
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