1,297 research outputs found

    Položaj kefalometrijske točke “A” nakon širenja nepca

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    Objectives: Palatal expansion is used to treat severely constricted maxillary arches associated with a posterior unilateral o f bilateral crossbite. The purpose of this study was to evaluate the affects of such treatment on the position of the “A ” point. Material and Methods: Ninety six cases where palatal expansion was the first orthodontic treatment were retrospectively analyzed using lateral cephalographs taken before and after the expansion phase. Vertical movement of “A ” point was assessed relative to the perpendicular distance from the Frankfort Horizontal Plane and from the anterior cranial base (Sella-Nasion). Horizontal movement o f “A ” point was measured parallel to the Frankfort Plane using a line tangenital to the posterior limit of the pterygomandibular fissure and also parallel to the anterior cranial base from point Sella. Subgroups o f “rapid” and “slow” palatal expansion were compared. Results: Here was a mean downward and forward movement o f point “A ” during palatal expansion, with displacement being greater on average with rapid than with slow palatal expansion therapy. The mean vertical component changes relative to speed of palatal expansion was statistically significant (p 1 mm more with rapid palatal expansion compared to slow expansion; however, no statistical significance was proven. Mean increase in the mandibular plane angel was 1.4° to 2.0°. Conclusions: Palatal expansion is generally associated with a downward and forward movement o f point “A ” which is greater on average with rapid than with slow activation therapy.Širenje nepca koristi se u terapji uskih maksilarnih lukova udruženih sa jednostranim ili obostranim kriznim zagrizom. Cilj je ovog ispitivanja bio utvrditi djelovanje takvog tretmana na točku “A ”. Laterolateralni rendgenkefalogrami devedeset i šest pacijenata gdje je širenje nepce bi prvi ortodontski zahvat analizirani su prije i poslije tretmana. Vertikalni pomaci točke “A ” promatran je u odnosu na vertiklanu udaljenost od Frankfurtske horizontale do prednje kranijalne baze (sela -nasion). Horizontalni pomak točke “A ” mjeren je paralelno s Frankfurtskom horizontalom od tangente stražnjeg ruba pterigomaksilarne fisure i paralelno s prednjom kranijalnom bazom od točke sela. Podgrupe ‘forsirano” i “sporo” širenje nepca također su međusobno uspoređene. Točka “A ” značajno se pomiče prema dolje i prema naprijed, s tim da je pomak značajniji u grupi s forsiranim širenjem. Vertikalni pomak u značajnoj je vezi s brzinom širenja nepca (p<0,l). Horizontalna komponenta pomaka prosječno je za više od 1 mm veća kod fosriranog nego kod sporog širenja; statistička značaj-nost nije pronađena. Povećanje inklinacije mandibularne ravnine iznosilo je od 1,4° do 2,0°. Sirenje nepca je povezano s pomakom toćke “A ” prema dolje i prema naprijed koje je veće kod pacijenata gdje se nepce forsirano širilo

    Statistics of non-linear stochastic dynamical systems under L\'evy noises by a convolution quadrature approach

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    This paper describes a novel numerical approach to find the statistics of the non-stationary response of scalar non-linear systems excited by L\'evy white noises. The proposed numerical procedure relies on the introduction of an integral transform of Wiener-Hopf type into the equation governing the characteristic function. Once this equation is rewritten as partial integro-differential equation, it is then solved by applying the method of convolution quadrature originally proposed by Lubich, here extended to deal with this particular integral transform. The proposed approach is relevant for two reasons: 1) Statistics of systems with several different drift terms can be handled in an efficient way, independently from the kind of white noise; 2) The particular form of Wiener-Hopf integral transform and its numerical evaluation, both introduced in this study, are generalizations of fractional integro-differential operators of potential type and Gr\"unwald-Letnikov fractional derivatives, respectively.Comment: 20 pages, 5 figure

    (B)On(e)-cohistones and the epigenetic alterations at the root of bone cancer

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    Identification of mutations in histones in a number of human neoplasms and developmental syndromes represents the most compelling evidence to date for a causal role of epigenetic perturbations in human disease. In most cases, these mutations have gain of function properties that cause deviation from normal developmental processes leading to embryo defects and/or neoplastic transformation. These exciting discoveries represent a step-change in our understanding of the role of chromatin (dys)regulation in development and disease. However, the mechanisms of action of oncogenic histone mutations (oncohistones) remain only partially understood. Here, we critically assess existing literature on oncohistones focussing mainly on bone neoplasms. We show how it is possible to draw parallels with some of the cell-autonomous mechanisms of action described in paediatric brain cancer, although the functions of oncohistones in bone tumours remain under-investigated. In this respect, it is becoming clear that histone mutations targeting the same residues display, at least in part, tissue-specific oncogenic mechanisms. Furthermore, it is emerging that cancer cells carrying oncohistones can modify the surrounding microenvironment to support growth and/or alter differentiation trajectories. A better understanding of oncohistone function in different neoplasms provide potential for identification of signalling that could be targeted therapeutically. Finally, we discuss some of the main concepts and future directions in this research area, while also drawing possible connections and parallels with other cancer epigenetic mechanisms

    An overview and update on soft tissue lesions of the head and neck

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    Soft tissue lesions of the head and neck encompass a broad range of pathological entities associated with different prognoses and requiring different treatments. All pathologists will encounter a wide range of soft tissue tumours in whatever specialist area they practice. Getting the diagnosis ‘right the first time’ is critical for patients to be offered optimal treatment. Molecular testing can help reach the correct diagnoses and this arena is developing fast. However, pathologists should not rely unquestioningly on special tests, whether it is immunohistochemistry or whole genome sequencing as no test is entirely specific or sensitive. Pathologists should provide a diagnosis in the context of all tests including the histology along with medical imaging and the patient's symptoms, signs and family history. This article reviews key clinical, pathological and histologic features of tumours most commonly presenting in the head and neck region, including those most recently described

    Should reduction of increased short-term blood pressure variability be a target of antihypertensive therapy?

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    It has long been known that blood pressure (BP) is characterized by marked short-term fluctuations occurring within a 24-h period and also by long-term oscillations occurring over more prolonged periods of time. An increased short-term blood pressure variability (BPV) appears to importantly contribute to target organ damage and to the enhanced cardiovascular risk of hypertensive patients, over and above the effect of an increase in mean BP levels. Reducing 24-h mean BP is the main aim of antihypertensive therapy, but initial data are available that additional cardiovascular protection can be achieved by reducing BPV. However, to definitively prove the prognostic role of short-term BPV and the need for its control by treatment, evidence is still needed from intervention trials aimed at demonstrating that by reducing BPV through administration of antihypertensive drugs, a reduction in organ damage and in the rate of cardiovascular events can be obtained

    A GIANT ANEURYSM OF PROPER HEPATIC ARTERY IN A CRYOGLOBULINEMIC PATIENT ON HEMODIALYSIS: A CASE REPORT.

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    Introductrion. Hepatic artery aneurysms (HAAs) are unusual vascular lesions often associated with many different pathological conditions. Most of reported cases are described in association with connective tissue diseases, such as polyarteritis nodosa and systemic lupus erythematosus. Case report. We observed a 52-year-old man with hypertension and HCV-related cryoglobulinemia complicated by end stage renal disease on replacement therapy by hemodialysis. He was admitted to our hospital because of the worsening of blood pressure values (170/110 mmHg) associated to new onset abdominal pain. After an initial physical examination, that showed a periumbelical bruit associated to a pulsatile mass in right hypocondrium, an abdominal ultrasound was performed with evidence of aneurysms of both the right branch (diameter max 4,5 cm) and the left branch (diameter max 1.5 cm) of the hepatic artery. An abdominal CT study was also performed and it confirmed the diagnosis of right intrahepatic artery aneurysm with partially thrombosed area in its peripheral distal portion. Discussion. Many different factors can contribute to the aneurysm formation in this patient. Vasculitic involvement due to cryoglobulinemic disease, therapy with steroid drugs, inflammatory state associated to HCV-related hepatitis, chronic kidney disease and replacement therapy by hemodialysis may all be involved in the development of the aneurysmatic hepatic lesion

    [OP.2D.05] RELATIONSHIP OF OXIDATIVE STRESS WITH CARDIAC HYPERTROPHY IN HYPERTENSIVE PATIENTS

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    OBJECTIVE: Left ventricular hypertrophy is common in hypertensive patients. In these subjects increased oxidative stress has been observed. Our aim was to evaluate the association of biomarkers of both oxidative stress and inflammation with markers of cardiovascular damage in a large group of hypertensives with different stages of renal function. DESIGN AND METHOD: In 517 hypertensives we analyzed left ventricular mass indexed for body surface area, and we assayed plasma levels of 8-isoprostaglandin F2alpha and high sensitivity C reactive protein. RESULTS: Multivariate analysis carried out considering left ventricular mass as dependent variable, and including 8-isoprostaglandin F2alpha, high sensitivity C reactive protein, age, sex, body mass index, estimated glomerular filtration rate, serum glucose, (log)triglycerides, hemoglobin, pulse pressure or systolic blood pressure, mean or diastolic blood pressure, and antihypertensive treatment showed that in hypertensives plasma levels of 8-isoprostaglandin F2alpha were correlated with left ventricular mass (beta=0.269, p\u200a<\u200a0.0001).The bivariate relationship of left ventricular mass with 8-isoprostaglandin F2alpha in hypertensives with estimated glomerular filtration rate higher and lower than 60\u200aml/min/1.73m2 was also calculated separately, demonstrating no significant differences in both correlations coefficients and slopes of the regression lines (r\u200a=\u200a0.254, p\u200a<\u200a0.001 and r\u200a=\u200a0.226, p\u200a<\u200a0.002; respectively).In the overall group, receiver operating characteristic curves showed that 8-isoprostaglandin F2alpha and high sensitivity C reactive protein were predictors of left ventricular hypertrophy, p\u200a<\u200a0.0001. CONCLUSIONS: To the best of our knowledge, this is the first demonstration that in hypertensives oxidative stress is correlated to left ventricular hypertrophy independently of other confounding factors. Oxidative stress might participate in the development of hypertensive cardiac hypertrophy

    The HIV-1 Nef Protein Interferes with Phosphatidylinositol 3-Kinase Activation 1

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    nef is a human immunodeficiency virus (HIV) gene encoding a 27-kDa myristoylated protein with structural features of a signal transducing molecule, but whose functions are largely unknown. We studied the interactions of Nef with the signal transduction pathways triggered by the platelet-derived growth factor (PDGF) receptor. The association of phosphatidylinositol (PI) 3-kinase with the activated receptor was severely impaired by nef expression. Conversely, PDGF-induced receptor tyrosine phosphorylation, binding to phospholipase C-gamma and to Ras-GAP were not modified. Microtubule-associated protein kinase activation and intracellular calcium influx in response to PDGF were either unaffected or only slightly enhanced. Nef significantly reduced the proliferative response to the growth factor, while the chemotactic response was unchanged. These data show that Nef affects selectively the PI 3-kinase signaling pathway and suggest that this interference results in some of the HIV adverse effects on host cell functions
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