Radiographers and COVID-19 pneumonia: Diagnostic performance using CO-RADS.

INTRODUCTION: A more structured role of radiographers is advisable to speed up the management of patients with suspected COVID-19. The purpose of our study was to evaluate the diagnostic performance of radiographers in the detection of COVID-19 pneumonia on chest CT using CO-RADS descriptors. METHODS: CT images of patients who underwent RT-PCR and chest CT due to COVID-19 suspicion between March and July 2020 were analysed retrospectively. Six readers, including two radiologists, two highly experienced radiographers and two less experienced radiographers, independently scored each CT using the CO-RADS lexicon. ROC curves were used to investigate diagnostic accuracy, and Fleiss'κ statistics to evaluate inter-rater agreement. RESULTS: 714 patients (419 men; 295 women; mean age: 64 years ±19SD) were evaluated. CO-RADS> 3 was identified as optimal diagnostic threshold. Highly experienced radiographers achieved an average sensitivity of 58.7% (95%CI: 52.5-64.7), an average specificity of 81.8% (95%CI: 77.9-85.2), and a mean AUC of 0.72 (95%CI: 0.68-0.75). Among less experienced radiographers, an average sensitivity of 56.3% (95%CI: 50.1-62.2) and an average specificity of 81.5% (95%CI: 77.6-84.9) were observed, with a mean AUC of 0.71 (95%CI: 0.68-0.74). Consultant radiologists achieved an average sensitivity of 60.0% (95%CI: 53.7-65.8), an average specificity of 81.7% (95%CI: 77.8-85.1), and a mean AUC of 0.73 (95%CI: 0.70-0.77). CONCLUSION: Radiographers can adequately recognise the classic appearances of COVID-19 on CT, as described by the CO-RADS assessment scheme, in a way comparable to expert radiologists. IMPLICATIONS FOR PRACTICE: Radiographers, as the first healthcare professionals to evaluate CT images in patients with suspected SARS-CoV-2 infection, could diagnose COVID-19 pneumonia by means of a categorical reporting scheme at CT in a reliable way, hence playing a primary role in the early management of these patients.

p14ARF interacts with the focal adhesion kinase and protects cells from anoikis.

The ARF protein functions as an important sensor of hyper-proliferative stimuli restricting cell proliferation through both p53-dependent and -independent pathways. Although to date the majority of studies on ARF have focused on its anti-proliferative role, few studies have addressed whether ARF may also have pro-survival functions. Here we show for the first time that during the process of adhesion and spreading ARF re-localizes to sites of active actin polymerization and to focal adhesion points where it interacts with the phosphorylated focal adhesion kinase. In line with its recruitment to focal adhesions, we observe that hampering ARF function in cancer cells leads to gross defects in cytoskeleton organization resulting in apoptosis through a mechanism dependent on the Death-Associated Protein Kinase. Our data uncover a novel function for p14ARF in protecting cells from anoikis that may reflect its role in anchorage independence, a hallmark of malignant tumor cells.

Modelling the interdependence between the stoichiometry of receptor oligomerization and ligand binding for a coexisting dimer/tetramer receptor system.

Many G protein-coupled receptors have been shown to exist as oligomers, but the oligomerization state and the effects of this on receptor function are unclear. For some G protein-coupled receptors, in ligand binding assays, different radioligands provide different maximal binding capacities. Here we have developed mathematical models for co-expressed dimeric and tetrameric species of receptors. We have considered models where the dimers and tetramers are in equilibrium and where they do not interconvert and we have also considered the potential influence of the ligands on the degree of oligomerization. By analogy with agonist efficacy, we have considered ligands that promote, inhibit or have no effect on oligomerization. Cell surface receptor expression and the intrinsic capacity of receptors to oligomerize are quantitative parameters of the equations. The models can account for differences in the maximal binding capacities of radioligands in different preparations of receptors and provide a conceptual framework for simulation and data fitting in complex oligomeric receptor situations.

[The effectiveness of training schemes in the treatment of acute coronary syndrome at health centers]. / Mejoría en la asistencia al síndrome coronario agudo en los centros de asistencia primaria mediante un plan de formación.

OBJECTIVE: A preliminary evaluation of the impact of a training program on pre-hospitalization care of acute coronary syndrome (ACS). DESIGN: A cross-sectional study. SETTING: Lleida Health Service area. PATIENTS: A total of 661 ACS cases were observed in the Intensive Medical Care Unit from January 1st 2002 to December 31st 2004. INTERVENTIONS: A training program for primary health care medical staff on the pre-hospitalization management of ACS from July 2003 to December 2006 in 29 health care centers was conducted. MAIN ENDPOINTS OF INTEREST: The evolution of 5 pre-hospitalization interventions, (acetylsalicylic acid, nitroglycerine, electrocardiogram, intravenous tube and intravenous morphine) throughout the study period was measured. RESULTS: It was noted during the study that those centers in which training programs were held had a clear increase in the use of the 5 pre-hospitalization interventions. Insertion of an intravenous line, administration of intravenous morphine and administration of acetylsalicylic acid were all observed to have multiplied their use 10, 8 and 3 times, respectively. CONCLUSIONS: A training scheme for general practitioners (GP) is essential to ensure appropriate care of patients with this condition.

TBP-1 protects the human oncosuppressor p14ARF from proteasomal degradation.

The p14ARF tumor suppressor is a key regulator of cellular proliferation, frequently inactivated in human cancer. The mechanisms that regulate alternative reading frame (ARF) turnover have been obscure for long time, being ARF a relatively stable protein. Recently, it has been described that its degradation depends, at least in part, on the proteasome and that it can be subjected to N-terminal ubiquitination. We have previously reported that ARF protein levels are regulated by TBP-1 (Tat-Binding Protein 1), a multifunctional protein, component of the regulatory subunit of the proteasome, involved in different cellular processes. Here we demonstrate that the stabilization effect exerted by TBP-1 requires an intact N-terminal 39 amino acids in ARF and occurs independently from N-terminal ubiquitination of the protein. Furthermore, we observed that ARF can be degraded in vitro by the 20S proteasome, in the absence of ubiquitination and this effect can be counteracted by TBP-1. These observations seem relevant in the comprehension of the regulation of ARF metabolism as, among the plethora of cellular ARF's interactors already identified, only NPM/B23 and TBP-1 appear to be involved in the control of ARF intracellular levels.

Cranial evolution in sakis (Pithecia, Platyrrhini). II: Evolutionary processes and morphological integration.

Patterns of interspecific differentiation in saki monkeys (Pithecia) are quantitatively described and possible evolutionary processes producing them are examined. The comparison of species correlation matrices to expected patterns of morphological integration reveal significant and similar patterns of development-based cranial integration among species. Aspects of the facial region are more heavily influenced by general size variation than features of the neural region. The comparison of pooled within- and between-groups V/CV matrices suggests that genetic drift might be a sufficient explanation for saki cranial evolution. Differential natural selection gradients are also reconstructed because selection may also have caused population differentiation through evolutionary time. These gradients illustrate the inherent multivariate nature of selection, being a consequence of the interaction between existing morphological integration (correlation) among traits and the action of natural selection. Yet, our attempt to interpret selection gradients in terms of their functional significance did not result in any clear association between selection and function. Perhaps this is also an indication that morphological evolution in sakis was mostly neutral.

ALX 5407: a potent, selective inhibitor of the hGlyT1 glycine transporter.

High-affinity glycine transport in neurons and glial cells is a primary means of inactivating synaptic glycine. We have synthesized a potent selective inhibitor of glycine transporter 1 (GlyT1), and characterized its activity using a quail fibroblast cell line (QT6). The glycine transporters GlyT1A, GlyT1B, GlyT1C, and GlyT2 were stably expressed in QT6 cells. The transporters expressed in these cells exhibited appropriate characteristics as described previously for these genes: Na(+)/Cl(-) dependence, appropriate K(m) values for glycine uptake, and appropriate pharmacology, as defined in part by the ability of N-methyl glycine (sarcosine) to competitively inhibit glycine transport. Furthermore, the characteristics of the transporters in the cell lines recapitulate the characteristics of glycine transporters observed in tissue preparations. We developed a sarcosine derivative, (R)-(N-[3-(4'-fluorophenyl)-3-(4'-phenylphenoxy)propyl])sarcosine (ALX 5407), and examined its activity against the cloned glycine transporters. ALX 5407 completely inhibited glycine transport in the GlyT1 cells, with an IC(50) value of 3 nM, but had little or no activity at the human GlyT2 transporter, at other binding sites for glycine, or at other neurotransmitter transporters. The inhibition of glycine transport was essentially irreversible. ALX 5407 represents a novel tool in the investigation of N-methyl-D-aspartate-receptor function. This class of drug may lead to novel therapies in the treatment of schizophrenia.

Polyamines in the basal ganglia of human brain. Influence of aging and degenerative movement disorders.

The distribution of polyamines in the human basal ganglia was examined, using dansyl-derivatives and high pressure liquid chromatography with fluorimetric detection. A heterogeneous distribution of putrescine, spermidine (SD) and spermine (SM) was observed in control brains. A consistent negative correlation between SD and SM content and age was found in different brain areas. These results suggest an involvement of polyamines in age-related changes occurring in white-matter. When the influence of degenerative movement disorders -Parkinson's disease, Huntington's disease (HD) and progressive supranuclear palsy- was analyzed, significant changes were observed only in HD, where a decrease in the concentration of SM was found in the putamen. These results suggest that in advanced stages of neurodegenerative processes, polyamines maintain their regulation. Only in the presence of severe atrophy, SM concentration is reduced.

The human tumor suppressor arf interacts with spinophilin/neurabin II, a type 1 protein-phosphatase-binding protein.

The INK4a gene, one of the most often disrupted loci in human cancer, encodes two unrelated proteins, p16(INK4a) and p14(ARF) (ARF) both capable of inducing cell cycle arrest. Although it has been clearly demonstrated that ARF inhibits cell cycle via p53 stabilization, very little is known about the involvement of ARF in other cell cycle regulatory pathways, as well as on the mechanisms responsible for activating ARF following oncoproliferative stimuli. In search of factors that might associate with ARF to control its activity or its specificity, we performed a yeast two-hybrid screen. We report here that the human homologue of spinophilin/neurabin II, a regulatory subunit of protein phosphatase 1 catalytic subunit specifically interacts with ARF, both in yeast and in mammalian cells. We also show that ectopic expression of spinophilin/neurabin II inhibits the formation of G418-resistant colonies when transfected into human and mouse cell lines, regardless of p53 and ARF status. Moreover, spinophilin/ARF coexpression in Saos-2 cells, where ARF ectopic expression is ineffective, somehow results in a synergic effect. These data demonstrate a role for spinophilin in cell growth and suggest that ARF and spinophilin could act in partially overlapping pathways.

Reversible erythrocyte skeleton destabilization is modulated by beta-spectrin phosphorylation in childhood leukemia.

The erythrocyte skeleton plays an essential role in determining the shape and deformability of the red cell. Disruption of the interaction between components of the red cell membrane skeleton may cause loss of structural and functional integrity of the membrane. Several observations based on studies in vitro strongly suggest that phosphorylation may modify interactions between proteins, leading to a reduced affinity. In particular, increased phosphorylation of beta-spectrin decreases membrane mechanical stability. In order to investigate the presence of membrane protein defects we investigated the erythrocyte membrane protein composition and phosphorylation in 22 children with leukemia at diagnosis and during the remission phase. Sixteen children had acute lymphoblastic leukemia (ALL), three had chronic myeloid leukemia (CML) and three had acute myeloid leukemia (AML). Ten patients (eight ALL and two CML) displayed elliptocytosis and poikilocytosis, an increase of spectrin dimers (41.8 +/- 15.6) and an enhanced phosphorylation of beta-spectrin (108 +/- 15%) at diagnosis. These alterations disappeared during the remission phase. This is the first demonstration of a reversible erythrocyte membrane alteration in leukemia. Since the beta-spectrin phosphate sites are located near the C-terminal region and close to the head of the beta-chain that is involved in dimer-dimer interaction, we supposed that the beta-chain phosphorylation has an effect upon the interactions between spectrin dimers, ie the tetramerization process. The weakening of this process should be responsible for the presence of elliptocytes and poikilocytes as reported in hereditary elliptocytosis and pyropoikilocytosis.

Giant inguino-scrotal bladder hernia. Report of a case.

Bladder hernia is very uncommon. It tends to affect patients over the age of 50 and is predisposed by cervico-urethral obstruction. The condition is often diagnosed during inguinal hernia surgery. The authors report a case of massive inguino-scrotal bladder herniation. The different types of bladder hernia are described, and the clinical-radiological findings and surgical management are discussed.

Epidural and subarachnoidal pneumocephalus after epidural technique.

Iatrogenic pneumocephalus is an uncommon complication observed after using the 'loss-of-resistance' technique with an air filled syringe. We report and review two cases of pneumocephalus: one subarachnoid and the other epidural.

Frequent de novo mutations of the ANK1 gene mimic a recessive mode of transmission in hereditary spherocytosis: three new ANK1 variants: ankyrins Bari, Napoli II and Anzio.

A subset of spherocytosis cases associated with mutations of the ANK1 gene present an apparently recessive inheritance pattern on a clinical and haematological basis. We identified three novel out-of-frame deletions in the ANK1 gene: allele Bari (1361delG), Napoli II (2883delC) and Anzio (3032delCA) in three Italian patients, two of whom have been splenectomized. Analysis of the cDNA showed small or trace amounts of ankyrin mRNAs in Bari, Napoli II and Anzio. The parents were normal clinically and haematologically and did not carry the mutations exhibited by their children. We confirmed the de novo character of the HS mutations based on paternity testing. Recessive HS associated with the ANK1 gene is probably rarer than initially thought, and spherocytosis may often be due to de novo mutations.

Total intravenous anaesthesia for caesarean section in a patient with Marfan's syndrome.

The case is described of a pregnant patient with Marfan's syndrome scheduled at 39 weeks' gestation for elective caesarean section carried out for the first time by total intravenous anaesthesia (TIVA) with continuous intravenous (i.v.) infusion of propofol. The diagnosis was based on a positive family history, classic phenotype, scoliosis, arachnodactyly, high narrow palate, hyperextensible joints, ectopia lentis and mitral valve prolapse, with a secondary low mitral insufficiency. Maternal and fetal surveillance did not detect complications during the course of pregnancy. Elective caesarean section was performed at 39 weeks due to high-risk pregnancy and to avoid the risk of haemodynamic alterations that take place during labour and delivery. The patient was given general anaesthesia with continuous i.v. infusion of propofol and boluses of atracurium and fentanyl after delivery. The haemodynamics and oxygen saturation remained stable during surgery. Apgar scores were 9 at 1 and 5 min. The post-delivery course was unremarkable and post partum echocardiography showed no changes from before caesarean section. The cardiovascular problems of Marfan's syndrome, the risk of haemodynamic changes associated with pregnancy and delivery, its anaesthetic implications and the possible advantages of TIVA with continuous i.v. infusion of propofol in the anaesthetic management of caesarean section in patients with this disease are discussed.

Increased membrane protein phosphorylation and anion transport activity in chorea-acanthocytosis.

BACKGROUND AND OBJECTIVE: Chorea-acanthocytosis is a disorder characterized by neuronal degeneration and the presence of acanthocytic erythrocytes on blood smear. The abnormal function and structure of the membrane protein band 3 are considered to be of pathogenetic relevance in determining the erythrocyte defect. METHODS: In a clinically evident case of chorea-acanthocytosis, the following parameters were investigated: membrane cholesterol and fatty acid composition, sulphate influx (as a measure of the anion transport activity), membrane protein phosphorylation, membrane casein and tyrosin-kinase activities; moreover, the promoter and all exons of the EPB3 gene were screened for possible mutations by single strand conformational polymorphism (SSCP) study. RESULTS: The sulphate influx, the Ser/Thr phosphorylation level, and the membrane casein-kinase activity were increased in chorea-acanthocytosis compared with normal controls. In the intact vanadate-treated 32P-labelled erythrocytes, Tyr-phosphorylation of the cytoplasmic domain of band 3, as well as the poly(Glu, Tyr) kinase activity in the membranes, were enhanced in the patient's sample. Apparent molecular weight and concentration of band 3 on SDS/PAGE analysis, membrane fatty acid composition and cholesterol/phospholipid molar ratio were normal and the SSCP study of EPB3 exons did not show any abnormal polymorphisms. INTERPRETATIONS AND CONCLUSIONS: An abnormal degree of phosphorylation of membrane proteins, in particular of band 2 (beta-subunit) and band 3, may contribute in determining both change of cell shape and increased anion transport in chorea-acanthocytosis.

Bombesin and thrombin affect discrete pools of intracellular calcium through different G-proteins.

In mouse NIH 3T3 cells, the mitogens bombesin and thrombin induced Ca2+ release from intracellular stores. Ca2+ release induced by bombesin was inhibited by the Ca(2+)-ATPase inhibitor thapsigargin, while Ca2+ release induced by thrombin was unaffected by this agent. The Ca(2+)-release response to bombesin was not affected by pertussis toxin, but the response to thrombin was abolished by the toxin. Stable transfectants overexpressing the G-protein subunit type alpha 9 showed an accentuated response to bombesin, indicating that the bombesin receptor was coupled to a Gq-like G-protein. Together, these results show that the two mitogenic receptors are coupled to distinct G-proteins that affect functionally different pools of Ca2+. Organization of signalling pathways in this manner may allow cells to differentially encode information from different signals.

[Anesthesia with continuous + infusion of propofol for trans-sternal thymectomy in myasthenic patients]. / Anestesia con infusión continua de propofol para timectomía transesternal en pacientes miasténicos.

Patients with myasthenia gravis respond unpredictably to muscle relaxants and more often suffer respiratory complications after surgery. We describe the use of total intravenous anesthesia with propofol and alfentanil without muscle relaxants is three myasthenic patients classified as Osserman I-IIB. Mean time since appearance of the disease was 1 year and all were undergoing transsternal thymectomy. Time in surgery ranged from 115 to 170 min and mean total dose of propofol was 1,374 mg. In all cases total intravenous anesthesia afforded good conditions for intubation, maintenance during surgery and rapid recovery from anesthesia, with early extubation.