366 research outputs found
Hepatitis C Virus Infection Among non-IDU HIV-Infected and Uninfected Men who Have Sex with Men
In the Mediterranean countries, hepatitis C virus infection affect nearly 45% of HIV-1 infected individuals, consistently to the high proportion of patients with a history of intravenous drug use and exposed to the two viruses by parenteral route. Even in association with HIV-infection, HCV infection is rarely transmitted through sexual intercourse due to the lower efficiency of mucosal exposure to virus than that blood-borne. Thus, the incidence and prevalence of HCV infection are far lower among the non-intravenous drug users (IDU) at risk of sexually transmitted infections (STI). Two hypotheses may be taken in account to explain the lower prevalence rates observed in our seroprevalence study. The MSMs participating to our study could have less sexual contacts with IDU-MSMs than other gay community residents in other western countries. The non-IDU MSMs recruited in this study could have a lower frequency of at-risk sexual practices for HCV then the non-IDU MSMs enrolled in other studies
Protective effects of the melanocortin analog NDP-α-MSH in rats undergoing cardiac arrest
We previously reported that melanocortins afford cardioprotection in conditions of experimental myocardial ischemia/reperfusion, with involvement of the janus kinases (JAK), extracellular signal-regulated kinases (ERK) and signal transducers and activators of transcription (STAT) signalings. We investigated the influence of the melanocortin analog [Nle(4), D-Phe(7)]α-melanocyte-stimulating hormone (NDP-α-MSH) on short-term detrimental responses to cardiac arrest (CA) induced in rats by intravenous (i.v.) administration of potassium chloride, followed by cardiopulmonary resuscitation (CPR) plus epinephrine treatment. In CA/CPR rats i.v. treated with epinephrine (0.1mg/kg) and returned to spontaneous circulation (48%) we recorded low values of mean arterial pressure (MAP) and heart rate (HR), alteration of hemogasanalysis parameters, left ventricle low expression of the cardioprotective transcription factors pJAK2 and pTyr-STAT3 (JAK-dependent), increased oxidative stress, up-regulation of the inflammatory mediators tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), and down-regulation of the anti-inflammatory cytokine IL-10, as assessed at 1h and 3h after CPR. On the other hand, i.v. treatment during CPR with epinephrine plus NDP-α-MSH (340μg/kg) almost completely restored the basal conditions of MAP and HR, reversed metabolic acidosis, induced left ventricle up-regulation of pJAK2, pTyr-STAT3 and IL-10, attenuated oxidative stress, down-regulated TNF-α and IL-6 levels, and improved survival rate by 81%. CA/CPR plus epinephrine alone or in combination with NDP-α-MSH did not affect left ventricle pSer-STAT3 (ERK1/2-dependent) and pERK1/2 levels. These results indicate that melanocortins improve return to spontaneous circulation, reverse metabolic acidosis, and inhibit heart oxidative stress and inflammatory cascade triggered by CA/CPR, likely via activation of the JAK/STAT signaling pathway
Mechanisms of Hydrogen Sulfide against the Progression of Severe Alzheimer’s Disease in Transgenic Mice at Different Ages
Abstract
Backgroud: Alzheimer disease is an age-related severe neurodegenerative
pathology. The level of the third endogenous
gas, hydrogen sulfide (H2S), is decreased in the brain of
Alzheimer’s disease (AD) patients compared with the brain
of the age-matched normal individuals; also, plasma H2S levels
are negatively correlated with the severity of AD. Recently,
we have demonstrated that systemic H2S injections are
neuroprotective in an early phase of preclinical AD. Objectives:
This study focuses on the possible neuroprotection of
a chronic treatment with an H2S donor and sulfurous water
(rich of H2S) in a severe transgenic 3×Tg-AD mice model.
Method: 3×Tg-AD mice at 2 different ages (6 and 12 months)
were daily treated intraperitoneally with an H2S donor and
sulfurous water (rich of H2S) for 3 months consecutively. We
investigated the cognitive ability, brain morphological alterations,
amyloid/tau cascade, excitotoxic, inflammatory and
apoptotic responses. Results: Three months of treatments
with H2S significantly protected against impairment in learning
and memory in a severe 3×Tg-AD mice model, at both
ages studied, and reduced the size of Amyloid β plaques
with preservation of the morphological picture. This neuroprotection
appeared mainly in the cortex and hippocampus,
associated with reduction in activity of c-jun N-terminal kinases,
extracellular signal-regulated kinases and p38, which
have an established role not only in the phosphorylation of
tau protein but also in the inflammatory and excitotoxic response.
Conclusion: Our findings indicate that appropriate
treatments with various sources of H2S, might represent an
innovative approach to counteract early and severe AD progression
in humans
Science with the ASTRI mini-array for the Cherenkov Telescope Array: Blazars and fundamental physics
ASTRI ("Astronomia a Specchi con Tecnologia Replicante Italiana") is a flagship project of the Italian Ministry of Research (MIUR), devoted to the realization, operation and scientific validation of an end-to-end prototype for the Small Size Telescope (SST) envisaged to become part of the Cherenkov Telescope Array (CTA). The ASTRI SST-2M telescope prototype is characterized by a dual mirror, Schwarzschild-Couder optical design and a compact camera based on silicon photo-multipliers. It will be sensitive to multi-TeV very high energy (VHE) gamma rays up to 100 TeV, with a PSF ∼ 6′ and a wide (9.6°) unaberrated optical field of view. Right after validation of the design in single-dish observations at the Serra La Nave site (Sicily, Italy) during 2015, the ASTRI collaboration will be able to start deployment, at the final CTA southern site, of the ASTRI mini-array, proposed to constitute the very first CTA precursor. Counting 9 ASTRI SST-2M telescopes, the ASTRI mini-array will overtake current IACT systems in differential sensitivity above 5 TeV, thus allowing unprecedented observations of known and predicted bright TeV emitters in this band, including some extragalactic sources such as extreme high-peaked BL Lacs with hard spectra. We exploited the ASTRI scientific simulator ASTRIsim in order to understand the feasibility of observations tackling blazar and cosmic ray physics, including discrimination of hadronic and leptonic scenarios for the VHE emission from BL Lac relativistic jets and indirect measurements of the intergalactic magnetic field and of the extragalactic background light. We selected favorable targets, outlining observation modes, exposure times, multi-wavelength coverage needed and the results expected. Moreover, the perspectives for observation of effects due to the existence of axion-like particles or to Lorentz invariance violations have been investigated
Gestational Diabetes and Thyroid Autoimmunity
Background. About 10% of pregnancies are complicated by previously unknown impairment of glucose metabolism, which is defined as gestational diabetes. There are little data available on prevalence of thyroid disorders in patients affected by gestational diabetes, and about their postgestational thyroid function and autoimmunity. We therefore investigated pancreatic and thyroid autoimmunity in gestational diabetic patients and in women who had had a previous gestational diabetic pregnancy. Methods. We investigated 126 pregnant women at the time of a 100-g oral glucose tolerance test: 91 were classified as gestational diabetics, and 35 were negative (controls). We also studied 69 women who had delivered a baby 18–120 months prior to this investigation and who were classified at that time gestational diabetics (38 women) or normally pregnant (31 women; controls). Results. Our data show no differences for both thyroid function and prevalence of autoimmune disorders during pregnancy; however, a significant increase in thyroid autoimmunity was seen in women previously affected by gestational diabetes. This increased prevalence of thyroid autoimmunity was not associated with the development of impaired glucose metabolism after pregnancy. Conclusions. Our data suggest that maternal hyperglycemia is a risk factor for the development of thyroid autoimmunity, a conclusion that should now be confirmed in a larger cohort of patients
Production of Composite Zinc Oxide–Polylactic Acid Radiopaque Filaments for Fused Deposition Modeling: First Stage of a Feasibility Study
Three-dimensional printing technologies are becoming increasingly attractive for their versatility; the geometrical customizability and manageability of the final product properties are the key points. This work aims to assess the feasibility of producing radiopaque filaments for fused deposition modeling (FDM), a 3D printing technology, starting with zinc oxide (ZnO) and polylactic acid (PLA) as the raw materials. Indeed, ZnO and PLA are promising materials due to their non-toxic and biocompatible nature. Pellets of PLA and ZnO in the form of nanoparticles were mixed together using ethanol; this homogenous mixture was processed by a commercial extruder, optimizing the process parameters for obtaining mechanically stable samples. Scanning electron microscopy analyses were used to assess, in the extruded samples, the homogenous distribution of the ZnO in the PLA matrix. Moreover, X-ray microtomography revealed a certain homogenous radiopacity; this imaging technique also confirmed the correct distribution of the ZnO in the PLA matrix. Thus, our tests showed that mechanically stable radiopaque filaments, ready for FDM systems, were obtained by homogenously loading the PLA with a maximum ZnO content of 6.5% wt. (nominal). This study produced multiple outcomes. We demonstrated the feasibility of producing radiopaque filaments for additive manufacturing using safe materials. Moreover, each phase of the process is cost-effective and green-oriented; in fact, the homogenous mixture of PLA and ZnO requires only a small amount of ethanol, which evaporates in minutes without any temperature adjustment. Finally, both the extruding and the FDM technologies are the most accessible systems for the additive manufacturing commercial apparatuses
Use of Antimicrobial Irrigation and Incidence of Capsular Contracture in Breast Augmentation and Immediate Implant Based Breast Reconstruction
t Capsular contracture (CC) is one of the most
common complications of implant-based breast reconstruction or augmentation surgery. Common risk factors of
CC include biofilm, surgical site infections, history of prior
CC or fibrosis, history of radiation therapy, and implant
characteristics. Though bacterial contamination of breast
protheses is associated with adverse sequelae, there are not
universally accepted guidelines and limited best practice
recommendations for antimicrobial breast pocket irrigation. Despite advanced molecular biology, the exact
mechanism of this complication is not fully understood.
Interventions that decrease the rate of CC include antibiotic
prophylaxis or irrigation, acellular dermal matrix, leukotriene inhibitors, surgical techniques, and others. However,
there is inconsistent evidence supporting these risk factors,
and the current data was based on broad heterogeneous
studies. The objective of this review was to provide a
summary of the current data of contributing risk factors as well as preventative and treatment measures for CC
Mechanism of Action of Bortezomib and the New Proteasome Inhibitors on Myeloma Cells and the Bone Microenvironment: Impact on Myeloma-Induced Alterations of Bone Remodeling
Multiple myeloma (MM) is characterized by a high capacity to induce alterations in the bone remodeling process. The increase in osteoclastogenesis and the suppression of osteoblast formation are both involved in the pathophysiology of the bone lesions in MM. The proteasome inhibitor (PI) bortezomib is the first drug designed and approved for the treatment of MM patients by targeting the proteasome. However, recently novel PIs have been developed to overcome bortezomib resistance. Interestingly, several preclinical data indicate that the proteasome complex is involved in both osteoclast and osteoblast formation. It is also evident that bortezomib either inhibits osteoclast differentiation induced by the receptor activator of nuclear factor kappa B (NF-κB) ligand (RANKL) or stimulates the osteoblast differentiation. Similarly, the new PIs including carfilzomib and ixazomib can inhibit bone resorption and stimulate the osteoblast differentiation. In a clinical setting, PIs restore the abnormal bone remodeling by normalizing the levels of bone turnover markers. In addition, a bone anabolic effect was described in responding MM patients treated with PIs, as demonstrated by the increase in the osteoblast number. This review summarizes the preclinical and clinical evidence on the effects of bortezomib and other new PIs on myeloma bone disease
Anal cytological abnormalities and epidemiological correlates among men who have sex with men at risk for HIV-1 infection
BACKGROUND: The incidence of anal cancer, a Human Papillomavirus (HPV)-related neoplasia, has been increasing in recent decades, mainly in men who have sex with men (MSM). Cytological changes of the anal epithelium induced by HPV can be detected through an anal pap smear. This study aimed to evaluate the prevalence and epidemiological correlates of anal cytological abnormalities among relatively young MSM at risk for HIV-1 infection, to help clarify whether or not this population deserves further investigation to assess the presence of anal cancer precursor lesions. METHODS: MSM were recruited among attendees of a large STI clinic for a HIV-1 screening program. Anal samples, collected with a Dracon swab in PreservCyt, were used both for liquid-based cytology and HPV testing by the Linear Array HPV Genotyping Test. Data regarding socio-demographic characteristics and sexual behavior were collected in face-to-face interviews. RESULTS: A total of 346 MSM were recruited (median age 32 years). Overall, 72.5% of the individuals had an anal HPV infection, with 56.1% of them being infected by oncogenic HPV genotypes. Anal cytological abnormalities were found in 29.8% of the cases (16.7% ASC-US and 13.1% L-SIL). Presence of ASC-US+ was strongly associated with infection by any HPV type (OR=4.21, 95% CI: 1.97-9.23), and particularly by HPV 16 and/or 18 (OR=5.62, 95% CI: 2.33-13.81). A higher proportion of ASC-US+ was found in older MSM, in those with a higher number of lifetime partners and in those with a history of ano-genital warts. However, none of these variables or the others analyzed showed any significant association with abnormal cytological findings. CONCLUSIONS: The presence of anal cytological abnormalities in about one third of the recruited MSM and their strong association with HPV infection, in particular that caused by HPV 16 and/or 18, might provide a further complement to the data that now support the introduction of HPV vaccination among MSM to protect them from the development of HPV-associated diseases. Additional studies are needed to determine whether and how screening for anal cancer precursor lesions should be performed in younger MSM
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