10 research outputs found

    Metal-Substituted Microporous Aluminophosphates

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    This chapter aims to present the zeotypes aluminophosphates (AlPOs) as a complementary alternative to zeolites in the isomorphic incorporation of metal ions within all-inorganic microporous frameworks as well as to discuss didactically the catalytic consequences derived from the distinctive features of both frameworks. It does not intend to be a compilation of either all or the most significant publications involving metal-substituted microporous aluminophosphates. Families of AlPOs and zeolites, which include metal ion-substituted variants, are the dominant microporous materials. Both these systems are widely used as catalysts, in particular through aliovalent metal ions substitution. Here, some general description of the synthesis procedures and characterization techniques of the MeAPOs (metal-contained aluminophosphates) is given along with catalytic properties. Next, some illustrative examples of the catalytic possibilities of MeAPOs as catalysts in the transformation of the organic molecules are given. The oxidation of the hardly activated hydrocarbons has probably been the most successful use of AlPOs doped with the divalent transition metal ions Co2+, Mn2+, and Fe2+, whose incorporation in zeolites is disfavoured. The catalytic role of these MeAPOs is rationalized based on the knowledge acquired from a combination of the most advanced characterization techniques. Finally, the importance of the high specificity of the structure-directing agents employed in the preparation of MeAPOs is discussed taking N,N-methyldicyclohexylamine in the synthesis of AFI-structured materials as a driving force. It is shown how such a high specificity could be predicted and how it can open great possibilities in the control of parameters as critical in catalysis as crystal size, inter-and intracrystalline mesoporosity, acidity, redox properties, incorporation of a great variety of heteroatom ions or final environment of the metal site (surrounding it by either P or Al)

    Molecular Detection of Bartonella schoenbuchensis from Ectoparasites of Deer in Massachusetts

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    Deer keds (Lipoptena cervi) are thought to have been introduced into New England from Europe during the 1800s. We sought to determine whether L. cervi from Massachusetts deer contained evidence of infection by Bartonella schoenbuchensis, which appears to be maintained by L. cervi in Europe. Five of 6 keds were found to contain B. schoenbuchensis DNA, and 2 deer ticks cofeeding on deer with such keds did as well. The detection of Bartonella DNA in deer ticks probably represents contamination by infected deer blood

    Conserved and divergent aspects of human T‐cell development and migration in humanized mice

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    Humanized mice represent an important model to study the development and function of the human immune system. While it is known that mouse thymic stromal cells can support human T-cell development, the extent of interspecies cross-talk and the degree to which these systems recapitulate normal human T-cell development remain unclear. To address these questions, we compared conventional and non-conventional T-cell development in a neonatal chimera humanized mouse model with that seen in human fetal and neonatal thymus samples, and also examined the impact of a human HLA-A2 transgene expressed by the mouse stroma. Given that dynamic migration and cell–cell interactions are essential for T-cell differentiation, we also studied the intrathymic migration pattern of human thymocytes developing in a murine thymic environment. We found that both conventional T-cell development and intra-thymic migration patterns in humanized mice closely resemble human thymopoiesis. Additionally, we show that developing human thymocytes engage in short, serial interactions with other human hematopoietic-derived cells. However, non-conventional T-cell differentiation in humanized mice differed from both fetal and neonatal human thymopoiesis, including a marked deficiency of Foxp3(+) T-cell development. These data suggest that although the murine thymic microenvironment can support a number of aspects of human T-cell development, important differences remain, and additional human-specific factors may be required

    Detection of hemoplasma and Bartonella species and co-infection with retroviruses in cats subjected to a spaying/neutering program in Jaboticabal, SP, Brazil Detecção de hemoplasmas e Bartonella sp. e co-infecção com retrovírus em gatos submetidos a um programa de castração/esterilização em Jaboticabal, SP, Brasil

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    Hemotrophic mycoplasmas and Bartonella species are important pathogens that circulate between cats and invertebrate hosts, occasionally causing diseases in humans. Nevertheless, there are few reports on occurrences of these agents in cats in Brazil. The present study aimed to detect the presence of hemoplasma and Bartonella DNA by means of PCR and sequencing. FIV antigens and anti-FeLV antibodies, were studied by using a commercial kit on blood and serum samples, respectively, among 46 cats that were sampled during a spaying/neutering campaign conducted in Jaboticabal, SP. Three (6.5%) cats were positive for hemoplasmas: two (4.3%) for 'Candidatus M. haemominutum' and one (2.2%) for both M. haemofelis and 'Candidatus M. turicensis'. One of the two 'Candidatus M. haemominutum'-infected cats was also positive for FeLV antigens and showed antibodies for FIV. Two cats (4.3%) were positive for B. henselae. One of them was also positive for FeLV antigens. Eight cats (17.4%) were positive for FeLV, and just one (2.2%) showed anti-FIV antibodies. Bartonella species and hemoplasmas associated with infection due to retroviruses can circulate among apparently healthy cats.<br>Micoplasmas hemotróficos e espécies de Bartonella são importantes patógenos que circulam entre gatos e hospedeiros invertebrados, causando ocasionalmente doenças no homem. Apesar disto, poucos são os estudos acerca da ocorrência destes agentes entre gatos no Brasil. O presente estudo objetivou detectar o DNA de hemoplasmas e Bartonella sp. pela PCR e sequenciamento. Antígeno de FIV e anticorpos anti-FeLV foram estudados utilizando um "kit" comercial, em amostras de sangue e soro, respectivamente, de 46 gatos amostrados em uma campanha de castração em Jaboticabal, SP. Três gatos (6,5%) foram positivos para hemoplasmas: dois (4,3%) para 'Candidatus M. haemominutum' e um (2,2%) para M. haemofelis and 'Candidatus M. turicensis'. Um dos gatos positivos para 'Candidatus M. haemominutum' mostrou-se também positivo na detecção de antígeno de FeLV e de anticorpos para FIV. Dois (4,3%) gatos mostraram-se positivos para B. henselae, sendo que um deles também se mostrou positivo para antígeno de FeLV. Oito gatos (17,4%) foram positivos para FeLV, e apenas um gato mostrou anticorpos anti-FIV. Bartonella sp. e hemoplasmas associados à infecção por retrovírus podem circular entre gatos aparentemente saudáveis

    Molecular characterisation of Bartonella species in cats from São Luís, state of Maranhão, north-eastern Brazil

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    Bartonella species are fastidious bacteria that predominantly infect mammalian erythrocytes and endothelial cells and cause long-lasting bacteraemia in their reservoir hosts. Reports that describe the epidemiology of bartonellosis in Brazil are limited. This study aimed to detect and characterise Bartonella spp DNA from cat blood samples in São Luís, Maranhão, north-eastern Brazil. Among 200 cats tested for multiple genes, nine (4.5%) were positive for Bartonella spp: six cats for Bartonella henselae and three for Bartonella clarridgeiae. Based on the phylogenetic analysis of four genes, the B. henselae strain matched strains previously observed in Brazil and was positioned in the same clade as B. henselae isolates from the United States of America. Moreover, sequence alignment demonstrated that the B. clarridgeiae strain detected in the present study was the same as the one recently detected in cats from southern Brazil

    Bartonellosis: A One Health Perspective

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    Global variation in postoperative mortality and complications after cancer surgery: a multicentre, prospective cohort study in 82 countries

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    © 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 licenseBackground: 80% of individuals with cancer will require a surgical procedure, yet little comparative data exist on early outcomes in low-income and middle-income countries (LMICs). We compared postoperative outcomes in breast, colorectal, and gastric cancer surgery in hospitals worldwide, focusing on the effect of disease stage and complications on postoperative mortality. Methods: This was a multicentre, international prospective cohort study of consecutive adult patients undergoing surgery for primary breast, colorectal, or gastric cancer requiring a skin incision done under general or neuraxial anaesthesia. The primary outcome was death or major complication within 30 days of surgery. Multilevel logistic regression determined relationships within three-level nested models of patients within hospitals and countries. Hospital-level infrastructure effects were explored with three-way mediation analyses. This study was registered with ClinicalTrials.gov, NCT03471494. Findings: Between April 1, 2018, and Jan 31, 2019, we enrolled 15 958 patients from 428 hospitals in 82 countries (high income 9106 patients, 31 countries; upper-middle income 2721 patients, 23 countries; or lower-middle income 4131 patients, 28 countries). Patients in LMICs presented with more advanced disease compared with patients in high-income countries. 30-day mortality was higher for gastric cancer in low-income or lower-middle-income countries (adjusted odds ratio 3·72, 95% CI 1·70–8·16) and for colorectal cancer in low-income or lower-middle-income countries (4·59, 2·39–8·80) and upper-middle-income countries (2·06, 1·11–3·83). No difference in 30-day mortality was seen in breast cancer. The proportion of patients who died after a major complication was greatest in low-income or lower-middle-income countries (6·15, 3·26–11·59) and upper-middle-income countries (3·89, 2·08–7·29). Postoperative death after complications was partly explained by patient factors (60%) and partly by hospital or country (40%). The absence of consistently available postoperative care facilities was associated with seven to 10 more deaths per 100 major complications in LMICs. Cancer stage alone explained little of the early variation in mortality or postoperative complications. Interpretation: Higher levels of mortality after cancer surgery in LMICs was not fully explained by later presentation of disease. The capacity to rescue patients from surgical complications is a tangible opportunity for meaningful intervention. Early death after cancer surgery might be reduced by policies focusing on strengthening perioperative care systems to detect and intervene in common complications. Funding: National Institute for Health Research Global Health Research Unit

    Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

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    © 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licenseBackground: Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide. Methods: A multimethods analysis was performed as part of the GlobalSurg 3 study—a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital. Findings: Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3·85 [95% CI 2·58–5·75]; p<0·0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63·0% vs 82·7%; OR 0·35 [0·23–0·53]; p<0·0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer. Interpretation: Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised. Funding: National Institute for Health and Care Research
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