5,265 research outputs found
de Sitter Vacua, Renormalization and Locality
We analyze the renormalization properties of quantum field theories in de
Sitter space and show that only two of the maximally invariant vacuum states of
free fields lead to consistent perturbation expansions. One is the Euclidean
vacuum, and the other can be viewed as an analytic continuation of Euclidean
functional integrals on . The corresponding Lorentzian manifold is the
future half of global de Sitter space with boundary conditions on fields at the
origin of time. We argue that the perturbation series in this case has
divergences at the origin, which render the future evolution of the system
indeterminate without a better understanding of high energy physics.Comment: JHEP Latex, 13 pages, v2. references adde
Spatial analysis of the 1999-2000 highly pathogenic avian influenza (H7N1) epidemic in northern Italy
The influence of diffusion- and relaxation-related factors on signal intensity: An introductive guide to magnetic resonance diffusion-weighted Imaging studies
Effects of a water extract of Lepidium meyenii root in different models of persistent pain in rats
Pomegranate mesocarp against colitis-induced visceral pain in rats: Effects of a decoction and its fractions
Impact of COVID-19 pandemic on Italian Otolaryngology Units: a nationwide study
Objective: The aim of this study was to provide an accurate picture of the changes which have occurred during the COVID-19 pandemic, and the contributions given by Italian Otolaryngology Units. Methods: A 29-item questionnaire was completed and returned by 154 Otorhinolaryngology Units across Italy that investigated geographic distribution, the main changes which occurred in workload management and in clinical and surgical activities and screening procedures for COVID-19 in healthcare personnel and patients. Results: Nearly half of the Otolaryngology Units that responded to the questionnaire were merged with other units, while 22% were converted into COVID-19 units or temporarily closed. A reduction of 8.55% in the number of team members was reported, and about 50% of the units applied uniform work shifts for all staff. Elective activities were uniformly stopped or delayed, passing from 30,295 (pre-COVID data) to 5,684 (COVID data) weekly procedures, with a mean decrease of 81.24% (p < 0.001). Conclusions: Most of the elective otolaryngology activities were suspended during the pandemic; the only procedures were for oncology and emergency patients. Italian Otolaryngologists have demonstrated a high availability to collaborate with non-surgical colleagues
Carbonic Anhydrase IV Selective Inhibitors Counteract the Development of Colitis-Associated Visceral Pain in Rats
Persistent pain affecting patients with inflammatory bowel diseases (IBDs) is still very difficult to treat. Carbonic anhydrase (CA) represents an intriguing pharmacological target considering the anti-hyperalgesic efficacy displayed by CA inhibitors in both inflammatory and neuropathic pain models. The aim of this work was to evaluate the effect of inhibiting CA IV, particularly when expressed in the gut, on visceral pain associated with colitis induced by 2,4-di-nitrobenzene sulfonic acid (DNBS) in rats. Visceral sensitivity was assessed by measuring animals’ abdominal responses to colorectal distension. Repeated treatment with the selective CA IV inhibitors AB-118 and NIK-67 effectively counteracted the development of visceral pain induced by DNBS. In addition to pain relief, AB-118 showed a protective effect against colon damage. By contrast, the anti-hyperalgesic activity of NIK-67 was independent of colon healing, suggesting a direct protective effect of NIK-67 on visceral sensitivity. The enzymatic activity and the expression of CA IV resulted significantly increased after DNBS injection. NIK-67 normalised CA IV activity in DNBS animals, while AB-118 was partially effective. None of these compounds influenced CA IV expression through the colon. Although further investigations are needed to study the underlying mechanisms, CA IV inhibitors are promising candidates in the search for therapies to relieve visceral pain in IBDs
Lectures on Supersymmetry Breaking
We review the subject of spontaneous supersymmetry breaking. First we
consider supersymmetry breaking in a semiclassical theory. We illustrate it
with several examples, demonstrating different phenomena, including metastable
supersymmetry breaking. Then we give a brief review of the dynamics of
supersymmetric gauge theories. Finally, we use this dynamics to present various
mechanisms for dynamical supersymmetry breaking. These notes are based on
lectures given by the authors in 2007, at various schools.Comment: 47 pages. v2: minor correction
Selective HCN1 block as a strategy to control oxaliplatin-induced neuropathy
Chemotherapy-Induced Peripheral Neuropathy (CIPN) is the most frequent adverse effect of pharmacological cancer treatments. The occurrence of neuropathy prevents the administration of fully-effective drug regimen, affects negatively the quality of life of patients, and may lead to therapy discontinuation. CIPN is currently treated with anticonvulsants, antidepressants, opioids and non-opioid analgesics, all of which are flawed by insufficient anti-hyperalgesic efficacy or addictive potential. Understandably, developing new drugs targeting CIPN-specific pathogenic mechanisms would dramatically improve efficacy and tolerability of anti-neuropathic therapies. Neuropathies are associated to aberrant excitability of DRG neurons due to the alteration in the expression or function of a variety of ion channels. In this regard, Hyperpolarization-activated Cyclic Nucleotide-gated (HCN) channels are overexpressed in inflammatory and neuropathic pain states, and HCN blockers have been shown to reduce neuronal excitability and to ameliorate painful states in animal models. However, HCN channels are critical in cardiac action potential, and HCN blockers used so far in pre-clinical models do not discriminate between cardiac and non-cardiac HCN isoforms. In this work, we show an HCN current gain of function in DRG neurons from oxaliplatin-treated rats. Biochemically, we observed a downregulation of HCN2 expression and an upregulation of the HCN regulatory beta-subunit MirP1. Finally, we report the efficacy of the selective HCN1 inhibitor MEL57A in reducing hyperalgesia and allodynia in oxaliplatin-treated rats without cardiac effects. In conclusion, this study strengthens the evidence for a disease-specific role of HCN1 in CIPN, and proposes HCN1-selective inhibitors as new-generation pain medications with the desired efficacy and safety profile
Acute febrile illness is associated with Rickettsia spp infection in dogs
BACKGROUND: Rickettsia conorii is transmitted by Rhipicephalus sanguineus ticks and causes Mediterranean Spotted Fever (MSF) in humans. Although dogs are considered the natural host of the vector, the clinical and epidemiological significance of R. conorii infection in dogs remains unclear. The aim of this prospective study was to investigate whether Rickettsia infection causes febrile illness in dogs living in areas endemic for human MSF. METHODS: Dogs from southern Italy with acute fever (n = 99) were compared with case–control dogs with normal body temperatures (n = 72). Serology and real-time PCR were performed for Rickettsia spp., Ehrlichia canis, Anaplasma phagocytophilum/A. platys and Leishmania infantum. Conventional PCR was performed for Babesia spp. and Hepatozoon spp. Acute and convalescent antibodies to R. conorii, E. canis and A. phagocytophilum were determined. RESULTS: The seroprevalence rates at first visit for R. conorii, E. canis, A. phagocytophilum and L. infantum were 44.8%, 48.5%, 37.8% and 17.6%, respectively. The seroconversion rates for R. conorii, E. canis and A. phagocytophilum were 20.7%, 14.3% and 8.8%, respectively. The molecular positive rates at first visit for Rickettsia spp., E. canis, A. phagocytophilum, A. platys, L. infantum, Babesia spp. and Hepatozoon spp. were 1.8%, 4.1%, 0%, 2.3%, 11.1%, 2.3% and 0.6%, respectively. Positive PCR for E. canis (7%), Rickettsia spp. (3%), Babesia spp. (4.0%) and Hepatozoon spp. (1.0%) were found only in febrile dogs. The DNA sequences obtained from Rickettsia and Babesia PCRs positive samples were 100% identical to the R. conorii and Babesia vogeli sequences in GenBank®, respectively. Febrile illness was statistically associated with acute and convalescent positive R. conorii antibodies, seroconversion to R. conorii, E. canis positive PCR, and positivity to any tick pathogen PCRs. Fourteen febrile dogs (31.8%) were diagnosed with Rickettsia spp. infection based on seroconversion and/or PCR while only six afebrile dogs (12.5%) seroconverted (P = 0.0248). The most common clinical findings of dogs with Rickettsia infection diagnosed by seroconversion and/or PCR were fever, myalgia, lameness, elevation of C-reactive protein, thrombocytopenia and hypoalbuminemia. CONCLUSIONS: This study demonstrates acute febrile illness associated with Rickettsia infection in dogs living in endemic areas of human MSF based on seroconversion alone or in combination with PCR
- …