1,565 research outputs found
Sintering and redispersion of Pt/γ-Al2O3 catalysts: a kinetic model
The sintering and redispersion kinetics of a Pt/Al2O3 naphtha reforming catalyst have been studied. The effect of the operating conditions, temperature, and oxygen and HCl concentration on the sintering and redispersion rates have been investigated. It was found that the rate of sintering depends on temperature and oxygen partial pressure. The rate of redispersion depends both on oxygen and HCl concentrations. A new kinetic model to study the sintering and redispersion phenomena has been developed. The model considers the evolution of the metallic dispersion as a reversible process and includes the effect of the operating conditions on the dispersion variation rate.Fil: Monzón, A.. Universidad de Zaragoza; EspañaFil: Garetto, Teresita Francisca. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Borgna, Armando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentin
Epidemiology and burden of Rotavirus-associated hospitalizations in Ferrara, Italy
Objective of this study was to provide data on hospitalizations for rotavirus gastroenteritis (RVGE) in Ferrara, Italy. The study was conducted analyzing the hospital discharge forms of all children admitted to the Pediatric Department of the University of Ferrara, Arcispedale Sant'Anna, from January 2001 through December 2005. The database was searched for all gastrointestinal diseases and in particular RVGE. During the period under study 3277 children, of which 2038 inf.60 months of age, were hospitalized; 247 children inf.5 years old were admitted for acute gastroenteritis and 89 (4.4% of all and 36% of gastroenteritis-related hospitalizations) had rapid screening tests positive for rotavirus. A seasonal pattern was observed for RVGE with an increase in winter and early spring. The average length of hospital stay was 5.7 days. The median cost of each hospitalized case of RVGE ranged between 1417 and 1595 Euros. The present research confirms that rotavirus gastroenteritis represents an important cause of hospitalization in children and is responsible for significant costs for the Public Health Care System. An effective vaccination program could significantly reduce the incidence of hospitalization and the associated costs
Laparoscopic surgery of adrenal cysts: results of a series of 18 patients
Indexación: Web of Science; Scielo.Introducción: Los quistes suprarrenales tienen una incidencia de 0,064% a 0,18% en autopsias. El objetivo de este trabajo es mostrar nuestra experiencia en 18 pacientes portadores de un quiste adrenal operados por vía laparoscópica. Material y Métodos: La serie está constituida por 18 pacientes, de una serie de 344 adrenalectomías laparoscópicas realizadas entre los años 1993 y 2011. El rango de edad fue de 20 a 61 años, con un promedio de 38 años, 11 mujeres y 7 hombres. Resultados: Trece quistes eran del lado izquierdo y 5 del derecho. El tamaño de la lesión varió entre 4,5 y 12,5 cm, con un promedio de 9,2 cm. En 8 pacientes hubo molestias abdominales vagas y en los restantes 12 pacientes no hubo signos ni síntomas de sospecha clínica. La cirugía realizada fue una decorticación-marsupialización laparoscópica en 11 pacientes, adrenalectomía laparoscópica en bloque en 8 casos y adrenalectomía parcial en 1 caso. El tiempo operatorio promedio fue de 83,1 min (30-180 min), y el tiempo medio de hospitalización fue de 36 h. Complicaciones intraoperatorias ocurrieron en 2 pacientes: 1 lesión de diafragma y 1 lesión de vena renal, reparadas en el mismo acto quirúrgico. Complicaciones postoperatorias ocurrieron en 2 pacientes, ambas Clavien 3a y de manejo conservador. Conclusión: Las lesiones pequeñas y no funcionantes requieren observación. La adrenalectomía laparoscópica parcial o total está indicada en lesiones de gran tamaño, con importante compromiso de la glándula o ante la sospecha de lesión funcionante o malignidad.Introduction: Adrenal cysts have an incidence of 0.064% to 0.18% at autopsy. Aim: To show our experience in 18 patients with an adrenal cyst operated by laparoscopy. Material and Methods: The series consisted of 18 patients operated, in a series of 344 laparoscopic adrenalectomy performed between 1993 and 2011. The age range was 20 to 61 years with an average of 38 years, 11 women and 7 men. Results: Thirteen cysts were left and 5 were right sided. The lesion size varied between 4.5 and 12.5 cm, with an average of 9.2 cm. Eight patients complained of abdominal discomfort and in the remaining 12 patients there were no signs or symptoms of clinical suspicion. The surgery performed was a laparoscopic decortication-marsupialization in 11 patients, laparoscopic adrenalectomy in 8 cases and partial adrenalectomy in 1 case. Mean operative time was 83.1 minutes (30-180 minutes), and mean hospital stay was 36 hours. Intraoperative complications occurred in 2 patients: 1 diaphragm injury and one renal vein injury, repaired in the same surgery. Postoperative complications occurred in 2 patients, both Clavien 3a, treated by conservative management. Conclusion: Small and non-functional lesions require observation. Partial or total laparoscopic adrenalectomy is indicated in large lesions or in functional and suspected malignant lesions.http://ref.scielo.org/bm4t5
the isolpharm project a new isol production method of high specific activity beta emitting radionuclides as radiopharmaceutical precursors
The ISOLPHARM project explores the feasibility of exploiting an innovative technology to produce extremely high specific activity beta-emitting radionuclides as radiopharmaceutical precursors. This technique is expected to produce radiopharmaceuticals that are virtually mainly impossible to obtain in standard production facilities, at lower cost and with less environmental impact than traditional techniques. The groundbreaking ISOLPHARM method investigated in this project has been granted an international patent (INFN). As a component of the SPES (Selective Production of Exotic Species) project at the Istituto Nazionale di Fisica Nucleare–Laboratori Nazionali di Legnaro (INFN–LNL), a new facility will produce radioactive ion beams of neutron-rich nuclei with high purity and a mass range of 80–160 amu. The radioactive isotopes will result from nuclear reactions induced by accelerating 40 MeV protons in a cyclotron to collide on a target of UC[Formula: see text]. The uranium in the target material will be [Formula: see text]U, yielding radioactive isotopes that belong to elements with an atomic number between 28 and 57. Isotope separation on line (ISOL) is adopted in the ISOLPHARM project to obtain pure isobaric beams for radiopharmaceutical applications, with no isotopic contaminations in the beam or subsequent trapping substrate. Isobaric contaminations may potentially affect radiochemical and radionuclide purity, but proper methods to separate chemically different elements can be developed
Long Noncoding Mitochondrial RNAs (LncmtRNAs) as Targets for Cancer Therapy
Mitochondria are traditionally been viewed as the cell’s powerhouse, generating most of its ATP. However, besides this fundamental metabolic role, mitochondria are implicated in diverse other processes, including apoptosis, inflammation and metastasis. These functions are exerted in part by the growing class of long noncoding mitochondrial RNAs (lncmtRNAs). We found that normal human proliferating cells express a family of noncoding mitochondrial RNAs (ncmtRNAs), comprised of sense (SncmtRNA) and antisense (ASncmtRNA). However, tumor cells express only sense transcripts, suggesting that ASncmtRNA downregulation as a cancer new hallmark. The few ASncmtRNAs copies in tumor cells seem essential to tumor cell viability: knockdown of these transcripts with antisense oligonucleotides (ASO) causes massive apoptotic death of tumor cells, preceded by cell cycle arrest. Preclinical assays show that systemic administration of ASO delayed tumor growth in melanoma and renal cancer models and, caused total remission in subcutaneous renal cancer tumors. The same treatment, however, does not affect normal tissue, suggesting this approach for the development of an efficient and safe therapeutic strategy for several cancer types
Pakistani children’s experiences of growing up with Beta-Thalassemia Major
In this study, we explored the lived experiences of children with beta-thalassemia major (β-TM). We considered children as experts on their experiences in contrast to the prevalent approach of asking parents or other adults about children’s perspectives. The sample consisted of 12 children aged 8 to12 years. There were two stages to data collection. In Stage 1 we employed two focus group discussions and two role plays and analyzed the data thematically. This directly informed Stage 2, consisting of 12 in-depth interviews subjected to interpretative phenomenological analysis. From our findings we show that living with β-TM involves a continuous struggle between feelings of being different and strategies to minimize these differences to strive for normalcy. We suggest that understanding the experiences of living with β-TM from children’s perspectives can provide unique insights into their experiences, which can fill the gap in the existing, predominantly adult-oriented research on chronic illness
Luspatercept improves hemoglobin levels and blood transfusion requirements in a study of patients with b-thalassemia
b-thalassemia is a hereditary disorder with limited approved treatment options; patients experience anemia and its complications, including iron overload. The study aim was to determine whether luspatercept could improve anemia and disease complications in patients with b-thalassemia. This open-label, nonrandomized, uncontrolled study consisted of a 24-week dose-finding and expansion stage (initial stage) and a 5-year extension stage, currently ongoing. Sixty-four patients were enrolled; 33 were non\u2013transfusion dependent (mean hemoglobin, <10.0 g/dL; <4 red blood cell [RBC] units transfused per 8 weeks), and 31 were transfusion dependent (\u20214 RBC units per 8 weeks). Patients received 0.2 to 1.25 mg/kg luspatercept subcutaneously every 21 days for \u20215 cycles (dose-finding stage) and 0.8 to 1.25 mg/kg (expansion cohort and 5-year extension). The primary end point was erythroid response, defined as hemoglobin increase of \u20211.5 g/dL from baseline for \u202114 consecutive days (without RBC transfusions) for non\u2013transfusion-dependent patients or RBC transfusion burden reduction \u202120% over a 12-week period vs the 12 weeks before treatment for transfusion-dependent patients. Eighteen non\u2013transfusion-dependent patients (58%) receiving higher dose levels of luspatercept (0.6-1.25 mg/kg) achieved mean hemoglobin increase \u20211.5 g/dL over \u202114 days vs baseline. Twenty-six (81%) transfusion-dependent patients achieved \u202120% reduction in RBC transfusion burden. The most common grade 1 to 2 adverse events were bone pain, headache, and myalgia. As of the cutoff, 33 patients remain on study. In this study, a high percentage of b-thalassemia patients receiving luspatercept had hemoglobin or transfusion burden improvements. These findings support a randomized clinical trial to assess efficacy and safety. This study was registered at www.clinicaltrials.gov as #NCT01749540 and #NCT02268409
Beta-thalassemia
Beta-thalassemias are a group of hereditary blood disorders characterized by anomalies in the synthesis of the beta chains of hemoglobin resulting in variable phenotypes ranging from severe anemia to clinically asymptomatic individuals. The total annual incidence of symptomatic individuals is estimated at 1 in 100,000 throughout the world and 1 in 10,000 people in the European Union. Three main forms have been described: thalassemia major, thalassemia intermedia and thalassemia minor. Individuals with thalassemia major usually present within the first two years of life with severe anemia, requiring regular red blood cell (RBC) transfusions. Findings in untreated or poorly transfused individuals with thalassemia major, as seen in some developing countries, are growth retardation, pallor, jaundice, poor musculature, hepatosplenomegaly, leg ulcers, development of masses from extramedullary hematopoiesis, and skeletal changes that result from expansion of the bone marrow. Regular transfusion therapy leads to iron overload-related complications including endocrine complication (growth retardation, failure of sexual maturation, diabetes mellitus, and insufficiency of the parathyroid, thyroid, pituitary, and less commonly, adrenal glands), dilated myocardiopathy, liver fibrosis and cirrhosis). Patients with thalassemia intermedia present later in life with moderate anemia and do not require regular transfusions. Main clinical features in these patients are hypertrophy of erythroid marrow with medullary and extramedullary hematopoiesis and its complications (osteoporosis, masses of erythropoietic tissue that primarily affect the spleen, liver, lymph nodes, chest and spine, and bone deformities and typical facial changes), gallstones, painful leg ulcers and increased predisposition to thrombosis. Thalassemia minor is clinically asymptomatic but some subjects may have moderate anemia. Beta-thalassemias are caused by point mutations or, more rarely, deletions in the beta globin gene on chromosome 11, leading to reduced (beta+) or absent (beta0) synthesis of the beta chains of hemoglobin (Hb). Transmission is autosomal recessive; however, dominant mutations have also been reported. Diagnosis of thalassemia is based on hematologic and molecular genetic testing. Differential diagnosis is usually straightforward but may include genetic sideroblastic anemias, congenital dyserythropoietic anemias, and other conditions with high levels of HbF (such as juvenile myelomonocytic leukemia and aplastic anemia). Genetic counseling is recommended and prenatal diagnosis may be offered. Treatment of thalassemia major includes regular RBC transfusions, iron chelation and management of secondary complications of iron overload. In some circumstances, spleen removal may be required. Bone marrow transplantation remains the only definitive cure currently available. Individuals with thalassemia intermedia may require splenectomy, folic acid supplementation, treatment of extramedullary erythropoietic masses and leg ulcers, prevention and therapy of thromboembolic events. Prognosis for individuals with beta-thalassemia has improved substantially in the last 20 years following recent medical advances in transfusion, iron chelation and bone marrow transplantation therapy. However, cardiac disease remains the main cause of death in patients with iron overload
The efficacy of iron chelator regimes in reducing cardiac and hepatic iron in patients with thalassaemia major: a clinical observational study
<p>Abstract</p> <p>Background</p> <p>Available iron chelation regimes in thalassaemia may achieve different changes in cardiac and hepatic iron as assessed by MR. The aim of this study was to assess the efficacy of four available iron chelator regimes in 232 thalassaemia major patients by assessing the rate of change in repeated measurements of cardiac and hepatic MR.</p> <p>Results</p> <p>For the heart, deferiprone and the combination of deferiprone and deferoxamine significantly reduced cardiac iron at all levels of iron loading. As patients were on deferasirox for a shorter time, a second analysis ("Initial interval analysis") assessing the change between the first two recorded MR results for both cardiac and hepatic iron (minimum interval 12 months) was made. Combination therapy achieved the most rapid fall in cardiac iron load at all levels and deferiprone alone was significantly effective with moderate and mild iron load. In the liver, deferasirox effected significant falls in iron load and combination therapy resulted in the most rapid decline.</p> <p>Conclusion</p> <p>With the knowledge of the efficacy of the different available regimes and the specific iron load in the heart and the liver, appropriate tailoring of chelation therapy should allow clearance of iron. Combination therapy is best in reducing both cardiac and hepatic iron, while monotherapy with deferiprone or deferasirox are effective in the heart and liver respectively. The outcomes of this study may be useful to physicians as to the chelation they should prescribe according to the levels of iron load found in the heart and liver by MR.</p
COVID-19 infection and diffusion among the healthcare workforce in a large university-hospital in northwest Italy
- …