357 research outputs found

    The Saccharomyces cerevisiae OXA1 gene is required for the correct assembly of cytochrome c oxidase and oligomycin-sensitive ATP synthase

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    AbstractThe nuclear gene OXA1 was first isolated in Saccharomyces cerevisiae and found to be required at a post-translational step in cytochrome c oxidase biogenesis, probably at the level of assembly. Mutations in OXA1 lead to a complete respiratory deficiency. The protein Oxa1p is conserved through evolution and a human homolog has been isolated by functional complementation of a yeast oxa1− mutant. In order to further our understanding of the role of Oxa1p, we have constructed two yeast strains in which the OXA1 open reading frame was almost totally deleted. Cytochrome spectra and enzymatic activity measurements show the absence of heme aa3 and of a cytochrome c oxido-reductase activity and dramatic decrease of the oligomycin sensitive ATPase activity. Analysis of the respiratory complexes in non-denaturing gels reveals that Oxa1p is necessary for the correct assembly of the cytochrome c oxidase and the ATP synthase complex

    The Majority of Yeast UPF1 Co-localizes with Polyribosomes in the Cytoplasm

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    In Saccharomyces cerevisiae the UPF1 protein is required for nonsense-mediated mRNA decay, the accelerated turnover of mRNAs containing a nonsense mutation. Several lines of evidence suggest that translation plays an important role in the mechanism of nonsense mRNA decay, including a previous report that nonsense mRNAs assemble in polyribosomes. In this study we show that UPF1 and ribosomal protein Li co-localize in the cytoplasm and that UPF1 co-sediments with polyribosomes. To detect UPF1, three copies of the influenza hemagglutinin epitope were placed at the C-terminus. The tagged protein, UPF1-3EP, retains 86% (± 5%) of function. Using immunological detection, we found that UPF1-3EP is primarily cytoplasmic and was not detected either in the nucleus or in the mitochondrion. UPF1-3EP and Li co-distributed with polyribosomes fractionated in a 7-47% sucrose gradient. The sucrose sedimentation profiles for UPF1-3EP and Li exhibited similar changes using three different sets of conditions that altered the polyribosome profile. When polyribosomes were disaggregated, UPF1-3EP and Li accumulated in fractions coincident with 80S ribosomal particles. These results suggest that UPF1-3EP associates with polyribosomes. L3 and S3 mRNAs, which code for ribosomal proteins of the 60S and 40S ribosomal subunits, respectively, were on average about 100-fold more abundant than UPF1 mRNA. Assuming that translation rates for L3, S3, and UPF1 mRNA are similar, this result suggests that there are far fewer UPF1 molecules than ribosomes per cell. Constraints imposed by the low UPF1 abundance on the functional relationships between UPF1, polyribosomes, and nonsense mRNA turnover are discussed

    Stapled hemorrhoidopexy: no more a new technique

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    Haemorrhoidal disease affect between 4.4% and 36.4% of the general population. The common symptoms are: bleeding, prolapse, pain, discharge, itching and hampered anal hygiene. There is no correlation between specific symptoms and anatomic grading. Apparently severe looking haemorrhoids can cause relatively few symptoms. Open haemorrhoidectomy, as described by Milligan, has been accepted worldwide as the best choice for treatment of symptomatic haemorrhoids. In 1998, Longo proposed a procedure for haemorrhoidectomy with minimal postoperative pain, no perianal wound requiring postoperative wound care and a relatively short operative time. His technique presented a new notion for treating haemorrhoids as he proposed circumferential rectal mucosectomy that results in mucosal lifting (anopexy). His aim was not excision of the haemorrhoidal tissue but rather restoring anatomical and physiological aspects of the haemorrhoidal plexus. The grading system described by Goligher, is the most commonly used and is based on objective findings and patient history. Stapled hemorrhoidopexy is performed for grade III and IV, for grade II in case of major bleeding. In lithotomy position and spinal anesthesia and after taking all aseptic precautions, the procedure of stapled hemorrhoidectomy was performed according to Longo’s technique. After this surgical procedure, the need to manually reduce prolapse will have been cured in approximately 90% of patients and the overall preoperative symptoms will be much reduced in the great majority. There should be no anal pain. Bowel habits should have returned to a normal pattern without urgency. One year follow-up or longer 11% of patients had remaining or recurrent prolapse, the reintervention rate is about 10%

    Invasive filamentous fungus infection with secondary cerebral vasculitis in a patient with no obvious immune suppression.

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    Summary Invasive mold infections represent an emerging and important diagnostic challenge, especially in immunocompetent patients when microscopy and cultures of the biological fluids remain negative. A central nervous system localization is not common and the clinical presentation is aspecific

    Spittlebugs of Mediterranean Olive Groves: Host-Plant Exploitation throughout the Year

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    Spittlebugs are the vectors of the bacterium Xylella fastidiosa Wells in Europe, the causal agent of olive dieback epidemic in Apulia, Italy. Selection and distribution of dierent spittlebug species on host-plants were investigated during field surveys in 2016–2018 in four olive orchards of Apulia and Liguria Regions of Italy. The nymphal population in the herbaceous cover was estimated using quadrat samplings. Adults were collected by sweeping net on three dierent vegetational components: herbaceous cover, olive canopy, and wild woody plants. Three species of spittlebugs were collected: Philaenus spumarius L., Neophilaenus campestris (Fallén), and Aphrophora alni (L.) (Hemiptera: Aphrophoridae). Philaenus spumarius was the predominant species both in Apulia and Liguria olive groves. Nymphal stages are highly polyphagous, selecting preferentially Asteraceae Fabaceae plant families, in particular some genera, e.g., Picris, Crepis, Sonchus, Bellis, Cichorium, and Medicago. Host-plant preference of nymphs varies according to the Region and through time and nymphal instar. In the monitored sites, adults peak on olive trees earlier in Apulia (i.e., during inflorescence emergence) than in Liguria (i.e., during flowering and beginning of fruit development). Principal alternative woody hosts are Quercus spp. and Pistacia spp. Knowledge concerning plant selection and ecological traits of spittlebugs in dierent Mediterranean olive production areas is needed to design eective and precise control strategies against X. fastidiosa vectors in olive groves, such as ground cover modifications to reduce populations of spittlebug vectors

    Lipoprotein(a) as a Risk Factor for Cardiovascular Diseases: Pathophysiology and Treatment Perspectives

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    Cardiovascular disease (CVD) is still a leading cause of morbidity and mortality, despite all the progress achieved as regards to both prevention and treatment. Having high levels of lipoprotein(a) [Lp(a)] is a risk factor for cardiovascular disease that operates independently. It can increase the risk of developing cardiovascular disease even when LDL cholesterol (LDL-C) levels are within the recommended range, which is referred to as residual cardiovascular risk. Lp(a) is an LDL-like particle present in human plasma, in which a large plasminogen-like glycoprotein, apolipoprotein(a) [Apo(a)], is covalently bound to Apo B100 via one disulfide bridge. Apo(a) contains one plasminogen-like kringle V structure, a variable number of plasminogen-like kringle IV structures (types 1–10), and one inactive protease region. There is a large inter-individual variation of plasma concentrations of Lp(a), mainly ascribable to genetic variants in the Lp(a) gene: in the general po-pulation, Lp(a) levels can range from 1000 mg/dL. Concentrations also vary between different ethnicities. Lp(a) has been established as one of the risk factors that play an important role in the development of atherosclerotic plaque. Indeed, high concentrations of Lp(a) have been related to a greater risk of ischemic CVD, aortic valve stenosis, and heart failure. The threshold value has been set at 50 mg/dL, but the risk may increase already at levels above 30 mg/dL. Although there is a well-established and strong link between high Lp(a) levels and coronary as well as cerebrovascular disease, the evidence regarding incident peripheral arterial disease and carotid atherosclerosis is not as conclusive. Because lifestyle changes and standard lipid-lowering treatments, such as statins, niacin, and cholesteryl ester transfer protein inhibitors, are not highly effective in reducing Lp(a) levels, there is increased interest in developing new drugs that can address this issue. PCSK9 inhibitors seem to be capable of reducing Lp(a) levels by 25–30%. Mipomersen decreases Lp(a) levels by 25–40%, but its use is burdened with important side effects. At the current time, the most effective and tolerated treatment for patients with a high Lp(a) plasma level is apheresis, while antisense oligonucleotides, small interfering RNAs, and microRNAs, which reduce Lp(a) levels by targeting RNA molecules and regulating gene expression as well as protein production levels, are the most widely explored and promising perspectives. The aim of this review is to provide an update on the current state of the art with regard to Lp(a) pathophysiological mechanisms, focusing on the most effective strategies for lowering Lp(a), including new emerging alternative therapies. The purpose of this manuscript is to improve the management of hyperlipoproteinemia(a) in order to achieve better control of the residual cardiovascular risk, which remains unacceptably high

    Longitudinal investigation of the parietal lobe anatomy in bipolar disorder and its association with general functioning

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    The parietal lobe (PL) supports cognitive domains, including attention and memory, which are impaired in bipolar disorder (BD). Although cross-sectional voxel-based morphometry studies found reduced PL grey matter (GM) in BD, none has longitudinally focused on PL anatomy in BD, relating it to patients? functioning. Thirty-eight right-handed BD patients and 42 matched healthy subjects (HS) underwent a Magnetic Resonance Imaging (MRI) scan at baseline. Seventeen BD patients and 16 matched HS underwent a follow-up MRI. PL white matter (WM) and GM volumes were measured. The trajectory of parietal volumes over time and the possible relation with the global functioning were investigated in both BD patients and HS. At baseline, BD patients showed significant reduced PL WM and GM and different WM laterality compared with HS. Furthermore, smaller PL WM volumes predicted lower global functioning in BD, but not in HS. At follow-up, although BD patients reported reduced PL WM compared with HS, no different pattern of volume changes over time was detected between groups. This study suggests the involvement of the PL in the pathophysiology of BD. In particular, PL WM reductions seem to predict an impairment in general functioning in BD and might represent a marker of functional outcome

    Imaging Evaluation of Pulmonary and Non-Ischaemic Cardiovascular Manifestations of COVID-19

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    Coronavirus Disease 2019 (COVID-19) has been a pandemic challenge for the last year. Cardiovascular disease is the most described comorbidity in COVID-19 patients, and it is related to the disease severity and progression. COVID-19 induces direct damage on cardiovascular system, leading to arrhythmias and myocarditis, and indirect damage due to endothelial dysfunction and systemic inflammation with a high inflammatory burden. Indirect damage leads to myocarditis, coagulation abnormalities and venous thromboembolism, Takotsubo cardiomyopathy, Kawasaki-like disease and multisystem inflammatory syndrome in children. Imaging can support the management, assessment and prognostic evaluation of these patients. Ultrasound is the most reliable and easy to use in emergency setting and in the ICU as a first approach. The focused approach is useful in management of these patients due its ability to obtain quick and focused results. This tool is useful to evaluate cardiovascular disease and its interplay with lungs. However, a detailed echocardiography evaluation is necessary in a complete assessment of cardiovascular involvement. Computerized tomography is highly sensitive, but it might not always be available. Cardiovascular magnetic resonance and nuclear imaging may be helpful to evaluate COVID-19-related myocardial injury, but further studies are needed. This review deals with different modalities of imaging evaluation in the management of cardiovascular non-ischaemic manifestations of COVID-19, comparing their use in emergency and in intensive care. View Full-Tex

    Epidemiology of atherosclerotic cardiovascular disease in polygenic hypercholesterolemia with or without high lipoprotein(a) levels

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    Background and aimsEpidemiology of atherosclerotic cardiovascular disease might be different in patients with polygenic hypercholesterolemia plus high levels (≥30 mg/dl) of Lp(a) (H-Lpa) than in those with polygenic hypercholesterolemia alone (H-LDL). We compared the incidence of peripheral artery disease (PAD), coronary artery disease (CAD), and cerebrovascular disease (CVD) in patients with H-Lpa and in those with H-LDL.MethodsRetrospective analysis of demographics, risk factors, vascular events, therapy, and lipid profile in outpatient clinical data. Inclusion criteria was adult age, diagnosis of polygenic hypercholesterolemia, and both indication and availability for Lp(a) measurement.ResultsMedical records of 258 patients with H-Lpa and 290 H-LDL were reviewed for occurrence of vascular events. The median duration of follow-up was 10 years (IQR 3–16). In spite of a similar reduction of LDL cholesterol, vascular events occurred more frequently, and approximately 7 years earlier (P = 0.024) in patients with H-Lpa than in H-LDL (HR 1.96 1.21–3.17, P = 0.006). The difference was around 10 years for acute events (TIA, Stroke, acute coronary events) and one year for chronic ones (P = 0.023 and 0.525, respectively). Occurrence of acute CAD was higher in H-Lpa men (HR 3.1, 95% CI 1.2–7.9, P = 0.007) while, among women, PAD was observed exclusively in H-Lpa subjects with smoking habits (P = 0.009).ConclusionsPatients with high Lp(a) levels suffer from a larger and earlier burden of the disease compared to those with polygenic hypercholesterolemia alone. These patients are at higher risk of CAD if they are men, and of PAD if they are women

    Factors associated with lifetime suicide attempts in bipolar disorder: results from an Italian nationwide study

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    The purpose of the present study was to detect demographic and clinical factors associated with lifetime suicide attempts in Bipolar Disorder (BD). A total of 1673 bipolar patients from different psychiatric departments were compared according to the lifetime presence of suicide attempts on demographic/clinical variables. Owing to the large number of variables statistically related to the dependent variable (presence of suicide attempts) at the univariate analyses, preliminary multiple logistic regression analyses were realized. A final multivariable logistic regression was then performed, considering the presence of lifetime suicide attempts as the dependent variable and statistically significant demographic/clinical characteristics as independent variables. The final multivariable logistic regression analysis showed that an earlier age at first contact with psychiatric services (odds ratio [OR] = 0.97, p < 0.01), the presence of psychotic symptoms (OR = 1.56, p < 0.01) or hospitalizations (OR = 1.73, p < 0.01) in the last year, the attribution of symptoms to a psychiatric disorder (no versus yes: OR = 0.71, partly versus yes OR = 0.60, p < 0.01), and the administration of psychoeducation in the last year (OR = 1.49, p < 0.01) were all factors associated with lifetime suicide attempts in patients affected by BD. In addition, female patients resulted to have an increased association with life-long suicidal behavior compared to males (OR: 1.02, p < 0.01). Several clinical factors showed complex associations with lifetime suicide attempts in bipolar patients. These patients, therefore, require strict clinical monitoring for their predisposition to a less symptom stabilization. Future research will have to investigate the best management strategies to improve the prognosis of bipolar subjects presenting suicidal behavior
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