Quantum corpuscular corrections to the Newtonian potential

We study an effective quantum description of the static gravitational potential for spherically symmetric systems up to the first post-Newtonian order. We start by obtaining a Lagrangian for the gravitational potential coupled to a static matter source from the weak field expansion of the Einstein-Hilbert action. By analysing a few classical solutions of the resulting field equation, we show that our construction leads to the expected post-Newtonian expressions. Next, we show that one can reproduce the classical Newtonian results very accurately by employing a coherent quantum state and modifications to include the first post-Newtonian corrections are considered. Our findings establish a connection between the corpuscular model of black holes and post-Newtonian gravity, and set the stage for further investigations of these quantum models.Comment: 26 pages, 4 figures. Typos corrected, references and clarifications adde

Erectile dysfunction in aging male

With the increasing longevity in men and women, sexual health concerns have become more and more important and demands for help are far more common than in the past. Erectile dysfunction's severity and prevalence both increase with aging: since erectile dysfunction is a symptom, physicians should diagnose underlying pathologies that might lead to it instead of focusing on finding a viable treatment. Cardiovascular alterations occur in the elderly, and might lead to erectile dysfunction because of penile blood flow impairment: diabetes, smoking, and sedentary life-style, being risk factors for vascular pathologies, can affect erectile function. Metabolic syndrome and psychological factors are highly prevalent in aging men, and might be other important determinants of erectile dysfunction.Drugs play a role in the pathogenesis of erectile dysfunction, as they can alter hormonal or vascular mechanics needed for achieving or maintaining erection. Alterations in penile vessels can be observed in the elderly: lack of androgens might lead to a reduction of smooth muscle cells content in the penis and an increase in the caliber of vascular spaces. Hypogonadism, when present, should be treated regardless of age; furthermore, synergistic effects have been found during testosterone replacement therapy when using an oral therapy with a PDE-5 inhibitor (sildenafil, vardenafil or tadalafil). These therapies are effective in the elderly, with no increase in the frequency of adverse events, and might also help in providing relief from lower urinary tract symptoms. (www.actabiomedica.it). © Mattioli 1885

Non-alcoholic fatty liver disease connections with fat-free tissues: A focus on bone and skeletal muscle

The estimates of global incidence and prevalence of non-alcoholic fatty liver disease (NAFLD) are worrisome, due to the parallel burden of obesity and its metabolic complications. Indeed, excess adiposity and insulin resistance represent two of the major risk factors for NAFLD; interestingly, in the last years a growing body of evidence tended to support a novel mechanistic perspective, in which the liver is at the center of a complex interplay involving organs and systems, other than adipose tissue and glucose homeostasis. Bone and the skeletal muscle are fat- free tissues which appeared to be independently associated with NAFLD in several cross-sectional studies. The deterioration of bone mineral density and lean body mass, leading to osteoporosis and sarcopenia, respectively, are age-related processes. The prevalence of NAFLD also increases with age. Beyond physiological aging, the three conditions share some common underlying mechanisms, and their elucidations could be of paramount importance to design more effective treatment strategies for the management of NAFLD. In this review, we provide an overview on epidemiological data as well as on potential contributors to the connections of NAFLD with bone and skeletal muscle

Chromogranin A: From Laboratory to Clinical Aspects of Patients with Neuroendocrine Tumors

Background. Neuroendocrine tumors (NETs) are characterized by having behavior and prognosis that depend upon tumor histology, primary site, staging, and proliferative index. The symptoms associated with carcinoid syndrome and vasoactive intestinal peptide tumors are treated with octreotide acetate. The PROMID trial assesses the effect of octreotide LAR on the tumor growth in patients with well-differentiated metastatic midgut NETs. The CLARINET trial evaluates the effects of lanreotide in patients with nonfunctional, well-, or moderately differentiated metastatic enteropancreatic NETs. Everolimus has been approved for the treatment of advanced pancreatic NETs (pNETs) based on positive PFS effects, obtained in the treated group. Sunitinib is approved for the treatment of patients with progressive gastrointestinal stromal tumor or intolerance to imatinib, because a randomized study demonstrated that it improves PFS and overall survival in patients with advanced well-differentiated pNETs. In a phase II trial, pasireotide shows efficacy and tolerability in the treatment of patients with advanced NETs, whose symptoms of carcinoid syndrome were resistant to octreotide LAR. An open-label, phase II trial assesses the clinical activity of long-acting repeatable pasireotide in treatment-naive patients with metastatic grade 1 or 2 NETs. Even if the growth of the neoplasm was significantly inhibited, it is still unclear whether its antiproliferative action is greater than that of octreotide and lanreotide. Because new therapeutic options are needed to counter the natural behavior of neuroendocrine tumors, it would also be useful to have a biochemical marker that can be addressed better in the management of these patients. Chromogranin A is currently the most useful biomarker to establish diagnosis and has some utility in predicting disease recurrence, outcome, and efficacy of therapy

Erectile dysfunction and its management in patients with diabetes mellitus

Diabetes can be described as a syndrome of multiple closely related conditions induced by a chronic state of hyperglycaemia resulting from defective insulin secretion, insulin action or both. Chronic complications associated with diabetes (including neuropathy, vascular disease, nephropathy and retinopathy) are common, and of these, erectile dysfunction (ED) deserves special attention. ED and its correlation with cardiovascular disease require careful evaluation and appropriate treatment. PDE5 inhibitors (PDE5is) are an important tool for the treatment of ED, with new drugs coming onto the market since the late 90s. This review offers an overview of PDE5is and their use in treating ED in diabetes. We underline the differences between different types of PDE5i, focusing on available doses, duration of action, T ½, side effects and selectivity profiles in relation to patients with diabetes. We also discuss the link between diabetes and ED in presence of various associated cofactors (obesity, hypertension and its pharmacological treatments, atherosclerosis, hyperhomocysteinaemia, neuropathy, nephropathy, hypogonadism and depression). Finally a number of past and ongoing clinical trials on the use of PDE5is in patients with diabetes are presented to offer an overview of the appropriate treatment of ED in this condition

Model of murine ventricular cardiac tissue for in vitro kinematic-dynamic studies of electromagnetic and beta2-adrenergic stimulation

In a model of murine ventricular cardiac tissue in vitro, we have studied the inotropic effects of electromagnetic stimulation (frequency, 75 Hz), isoproterenol administration (10 μM), and their combination. In particular, we have performed an image processing analysis to evaluate the kinematics and the dynamics of beating cardiac syncytia starting from the video registration of their contraction movement. We have found that the electromagnetic stimulation is able to counteract the β-adrenergic effect of isoproterenol and to elicit an antihypertrophic response