62 research outputs found

    Survival and senescence of human young red cells in vitro.

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    Background: A number of experimental investigations in vivo suggest that in humans a decrease of circulating erythrocyte number ensues whenever erythropoietin (EPO) plasma level decreases. Since the process seems to selectively eliminate young red cells (neocytes), it has been named neocytolysis. The experimental models in vivo have revealed and documented multiple forms of neocytolysis but have not fully elucidated the specificity of the target red cells and the relation with EPO level changes. In an attempt to better characterize the neocytolytic process, we have undertaken an in vitro investigation on age-ranked human red cells. Methods: By centrifugation on Percoll density gradient we separated the red cells population into three subsets, neocytes, middle-aged and old. Then we comparatively investigated the kinetics of survival of the subsets cultured under different conditions: with medium alone, with 10% autologous plasma, with EPO, alone or in combination with autologous monocytes. Results: Neocytes showed a viability and a survival rate lower than the other red cells when cultured in medium or with 10% plasma. EPO at physiological doses increased their survival rate, but not that of the other subsets. This effect was enhanced by co-culture with monocytes. Conclusion: Likely neocytes are more sensitive than the other RBCs subsets to presence or absence of survival signals, such as EPO or plasma or monocytes derived factors. These observations could provide an insight into the link between the decrease in EPO plasma level and the reduction of circulating red cells mass and account for the specificity of neocytes clearance

    Sex attribution, gender identity and quality of life in disorders of sex development due to 45,X/46,XY mosaicism: methods for clinical and psychosocial assessment.

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    The choice of sex in newborns with genital ambiguity is challenging. Information concerning the satisfaction of subjects with disorders of sex development from childhood to adulthood is required in order to address sex attribution policies. This study focuses on the methods that enable clinicians to investigate the alignment of phenotypes with gender identity and quality of life in people with disorders of this kind. These methods are presented as tools for studying a cohort of ten subjects with 45,X/46,XY mosaicism examined between 1985 and 2014 in the Department of Pediatric Endocrinology, Regina Margherita Children's Hospital, Turin: five children and five young adults, four reared as females and six as males. Clinical outcome was assessed by means of a clinical scoring system considering height, genital appearance, gonads and pubertal development. The Gender Identity Questionnaire for Children and the World Health Organization Quality of Life assessment were adopted. The four male children strongly identified with their assigned sex: male attribution was satisfactory until pubertal age. In young adults the clinical scores ranged between 55-65% for both genders. In the young male, the reduced sexual activity and the poor body image perception strongly affected his quality of life. The clinical scores of the two young female adults (60% for both) were not balanced with their quality of life scores (87.5% and 68.75% respectively): individual traits and social-familial context should be investigated in order to explain these differences. Clinical and psychosocial assessment in people with disorders of sex development is mandatory in order to plan care procedures; a detailed analysis requires adequate tools. Clinical scoring system, Gender Identity Questionnaire for Children and World Health Organization Quality of Life assessment can be used to investigate the alignment of physical phenotype with gender identity and quality of life

    An Overview of Brazilian Scientific Production on Disasters in the Beginning of this Century

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    Este artigo busca contribuir para a compreensão de como vem se delineando a produção científica brasileira sobre desastres no início do século XXI, a partir de levantamento de três tipos de publicações: i) teses e dissertações; ii) artigos em periódicos brasileiros indexados na base SciELO; e iii) artigos em periódicos indexados na base de dados Web of Science que tenha um ou mais pesquisadores brasileiros como autores. Os resultados indicam as principais áreas do conhecimento que têm se dedicado à realização de pesquisas sobre o tema, a produção acadêmica em formato de teses e dissertações e as publicações em periódicos nacionais e internacionais com autores e/ou coautores brasileiros. Evidencia alguns aspectos envolvidos no crescimento da produção científica brasileira sobre desastres a partir de 2008, abordando os principais temas das investigações e possíveis tendências nesse campo.In this article we seek to present an overview of Brazilian scientific production on disasters in the beginning of this century based on a review of three data bases: (i) PhD Thesis and Master Dissertations; (ii) articles in Brazilian journals indexed in SciELO database; and (iii) articles indexed in Web of Science database which have Brazilian researchers among the authors. The results point out the main scientific areas, and PhD Thesis and Master Dissertations which have focused this subject. Our results also bring forward the published papers in national and international journals which are focused on disaster issue and have been produced by Brazilian authors. We also seek to debate some aspects related to the increase of Brazilian scientific production on disasters after 2008, and to point out possible trends on this field

    Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

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    Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe

    Survival and Senescence of Human Young Red Cells in Vitro

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    Background: A number of experimental investigations in vivo suggest that in humans a decrease of circulating erythrocyte number ensues whenever erythropoietin (EPO) plasma level decreases. Since the process seems to selectively eliminate young red cells (neocytes), it has been named neocytolysis. The experimental models in vivo have revealed and documented multiple forms of neocytolysis but have not fully elucidated the specificity of the target red cells and the relation with EPO level changes. In an attempt to better characterize the neocytolytic process, we have undertaken an in vitro investigation on age-ranked human red cells. Methods: By centrifugation on Percoll density gradient we separated the red cells population into three subsets, neocytes, middle-aged and old. Then we comparatively investigated the kinetics of survival of the subsets cultured under different conditions: with medium alone, with 10% autologous plasma, with EPO, alone or in combination with autologous monocytes. Results: Neocytes showed a viability and a survival rate lower than the other red cells when cultured in medium or with 10% plasma. EPO at physiological doses increased their survival rate, but not that of the other subsets. This effect was enhanced by co-culture with monocytes. Conclusion: Likely neocytes are more sensitive than the other RBCs subsets to presence or absence of survival signals, such as EPO or plasma or monocytes derived factors. These observations could provide an insight into the link between the decrease in EPO plasma level and the reduction of circulating red cells mass and account for the specificity of neocytes clearance

    Application of gelatin Zymography for evaluating low levels of contaminating neutrophils in red blood cell samples

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    Supposedly \u2018\u2018homogeneous\u2019\u2019 red blood cell (RBC) samples are commonly obtained by \u2018\u2018washing\u2019\u2019 whole blood free of plasma, platelets, and white cells with physiological solutions, a procedure that does not result, however, in sufficient removal of polymorphonuclear neutrophils (PMNs), leading to possible artifactual results. Pure RBC samples can be obtained only by leukodepletion procedures. Proposed here is a version of gelatin zymography adapted to detect matrix metalloproteinase 9 (MMP-9), selectively expressed by PMNs, in heterogeneous mixtures of RBCs and PMNs that can reveal contamination at levels as low as 1 PMN/106 RBCs

    SMAP-29: a potent antibacterial and antifungal peptide from sheep leukocytes

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    AbstractSMAP-29 is a cathelicidin-derived peptide deduced from sheep myeloid mRNA. The C-terminally amidated form of this peptide was chemically synthesized and shown to exert a potent antimicrobial activity. Antibiotic-resistant clinical isolates highly susceptible to this peptide include MRSA and VREF isolates, that are a major worldwide problem, and mucoid Pseudomonas aeruginosa associated with chronic respiratory inflammation in CF patients. In addition, SMAP-29 is also active against fungi, including Cryptococcus neoformans isolated from immunocompromised patients. SMAP-29 causes significant morphological alterations of the bacterial surfaces, as shown by scanning electron microscopy, and is also hemolytic against human, but not sheep erythrocytes. Its potent antimicrobial activity suggests that this peptide is an excellent candidate as a lead compound for the development of novel antiinfective agents

    Freely turning over palmitate in erythrocyte membrane proteins is not responsible for the anchoring of lipid rafts to the spectrin skeleton: A study with bio-orthogonal chemical probes

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    6Erythrocyte lipid rafts are anchored to the underlying spectrin membrane skeleton [A. Ciana, C. Achilli, C. Balduini, G. Minetti, On the association of lipid rafts to the spectrin skeleton in human erythrocytes, Biochim. Biophys. Acta 1808 (2011) 183–190]. The nature of this linkage and the molecules involved are poorly understood. The interaction is sensitive to the increase in pH and ionic strength induced by carbonate. Given the role of palmitoylation in modulating the partitioning of certain proteins between various sub-cellular compartments and the plasma membrane, we asked whether palmitoylation of p55, a peripheral protein located at the junctional complex between spectrin-actin-protein 4.1 that anchors the membrane skeleton to the lipid bilayer via the transmembrane protein glycophorin C, could contribute to the anchoring of lipid rafts to the membrane skeleton. We adopted a new, non-radioactive method for studying protein palmitoylation, based on bio-orthogonal chemical analogues of fatty acids, containing an omega-alkynyl group, to metabolically label cell proteins, which are then revealed by a “click chemistry” reaction of the alkynyl moiety with an azide-containing reporter tag. We show that the membrane localization and palmitoylation levels of p55 did not change after carbonate treatment. 2-bromopalmitate and cerulenin, two known palmitoylation inhibitors, completely inhibited p55 palmitoylation, and protein palmitoyl thioesterase-1 (PPT1) reduced it, without affecting the association between lipid rafts and membrane-skeleton, indicating, on the one hand, that p55 palmitoylation is enzymatic, and, on the other, that it is not involved in the modulation of the linkage of lipid rafts to the membrane-skeleton.reservedmixedAnnarita Ciana;Cesare Achilli;Rami N. Hannoush;Angela Risso;Cesare Balduini;Giampaolo MinettiAnnarita, Ciana; Cesare, Achilli; Rami N., Hannoush; Risso, Angela; Cesare, Balduini; Giampaolo, Minett
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