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1.
Phys Rev Lett ; 131(10): 102502, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37739382

RESUMO

The absolute scale of the neutrino mass plays a critical role in physics at every scale, from the subatomic to the cosmological. Measurements of the tritium end-point spectrum have provided the most precise direct limit on the neutrino mass scale. In this Letter, we present advances by Project 8 to the cyclotron radiation emission spectroscopy (CRES) technique culminating in the first frequency-based neutrino mass limit. With only a cm^{3}-scale physical detection volume, a limit of m_{ß}<155 eV/c^{2} (152 eV/c^{2}) is extracted from the background-free measurement of the continuous tritium beta spectrum in a Bayesian (frequentist) analysis. Using ^{83m}Kr calibration data, a resolution of 1.66±0.19 eV (FWHM) is measured, the detector response model is validated, and the efficiency is characterized over the multi-keV tritium analysis window. These measurements establish the potential of CRES for a high-sensitivity next-generation direct neutrino mass experiment featuring low background and high resolution.

2.
Prev Sci ; 24(Suppl 1): 40-49, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36399222

RESUMO

Given increasing opioid overdose mortality rates in the USA over the past 20 years, accelerating the implementation of prevention interventions found to be effective is critical. The Helping End Addiction Long-Term (HEAL) Prevention Cooperative (HPC) is a consortium of research projects funded to implement and test interventions designed to prevent the onset or escalation of opioid misuse among youth and young adults. The HPC offers a unique opportunity to synthesize and share lessons learned from participating research projects' varied implementation experiences, which can facilitate quicker integration of effective prevention interventions into practice. This protocol paper describes our hybrid approach to collecting and analyzing information about the implementation experiences of nine of the HPC research projects while they maintain their focus on assessing the effectiveness and cost-effectiveness of prevention interventions. To better understand implementation within this context, we will address five research questions: (1) What were the context and approach for implementing the prevention interventions, and how was the overall implementation experience? (2) How representative of the target population are the participants who were enrolled and retained in the research projects' effectiveness trials? (3) For what purposes and how were stakeholders engaged by the research projects? (4) What are the adaptable components of the prevention interventions? And finally, (5) how might implementation of the prevention interventions vary for non-trial implementation? This work will result in intervention-specific and general practical dissemination resources that can help potential adopters and deliverers of opioid misuse prevention make adoption decisions and prepare for successful implementation.


Assuntos
Comportamento Aditivo , Overdose de Drogas , Transtornos Relacionados ao Uso de Opioides , Adolescente , Adulto Jovem , Humanos , Overdose de Drogas/prevenção & controle , Transtornos Relacionados ao Uso de Opioides/prevenção & controle
3.
Public Health ; 127(2): 171-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23313162

RESUMO

OBJECTIVE: To quantify and determine factors associated with delay in initiation of tuberculosis (TB) treatment in the Thames Valley area, South East England, and the proportion of this delay that could be attributed to patient care-seeking or to delay within the National Health Service (NHS). STUDY DESIGN: Retrospective analysis study reviewing medical notes and enhanced TB surveillance data. METHODS: Demographic and clinical information was collected from medical notes and the Enhanced TB Surveillance database for patients who were diagnosed with TB and resident in the Thames Valley. Treatment delay was defined as the period between the onset of symptoms and the start of treatment. Patient delay was defined as the period between the onset of symptoms and the first presentation to the NHS. Health service delay was defined as the period between the first contact with the NHS and the start of treatment. Univariate and multivariate linear regression analyses were used to assess the association between delays and explanatory variables (age, gender, place of birth, ethnicity, disease site, sputum smear, culture, primary care trust of residence). RESULTS: The study included 273 patients with TB. The median time between symptom onset and initiation of treatment was 73 days [95% confidence interval (CI) 65-89], of which the contributions of health service, patient and referral delays were 39 (95% CI 34-55), 29 (95% CI 22-36) and 16 (95% CI 12-24) days, respectively. On multivariate analysis, extrapulmonary TB (P = 0.010), female (P = 0.003) and UK-born (P = 0.008) patients were associated with longer health service delay. Age (P = 0.001) and extrapulmonary TB (P = 0.010) were associated with longer overall treatment delay. CONCLUSION: Treatment delay for TB, especially delay after first presentation to the NHS, remains a public health concern. Differences in health service delay, for example by gender and country of birth, highlight that some of this should be open to health service intervention.


Assuntos
Tempo para o Tratamento/estatística & dados numéricos , Tuberculose Pulmonar/terapia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Inglaterra , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Estudos Retrospectivos , Fatores de Risco , Medicina Estatal , Adulto Jovem
4.
Epidemiol Infect ; 140(6): 1102-10, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21859502

RESUMO

A pandemic influenza A(H1N1) 2009 outbreak in a summer school affected 117/276 (42%) students. Residential social contact was associated with risk of infection, and there was no evidence for transmission associated with the classroom setting. Although the summer school had new admissions each week, which provided susceptible students the outbreak was controlled using routine infection control measures (isolation of cases, basic hygiene measures and avoidance of particularly high-risk social events) and prompt treatment of cases. This was in the absence of chemoprophylaxis or vaccination and without altering the basic educational activities of the school. Modelling of the outbreak allowed estimation of the impact of interventions on transmission. These models and follow-up surveillance supported the effectiveness of routine infection control measures to stop the spread of influenza even in this high-risk setting for transmission.


Assuntos
Controle de Infecções/métodos , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Pandemias , Instituições Acadêmicas , Adolescente , Criança , Feminino , Humanos , Masculino , Estações do Ano
5.
Epidemiol Infect ; 140(9): 1695-701, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22129511

RESUMO

An outbreak of gastroenteritis affected at least 240 persons who had eaten at a gourmet restaurant over a period of 7 weeks in 2009 in England. Epidemiological, microbiological, and environmental studies were conducted. The case-control study demonstrated increased risk of illness in those who ate from a special 'tasting menu' and in particular an oyster, passion fruit jelly and lavender dish (odds ratio 7·0, 95% confidence interval 1·1-45·2). Ten diners and six staff members had laboratory-confirmed norovirus infection. Diners were infected with multiple norovirus strains belonging to genogroups I and II, a pattern characteristic of molluscan shellfish-associated outbreaks. The ongoing risk from dining at the restaurant may have been due to persistent contamination of the oyster supply alone or in combination with further spread via infected food handlers or the restaurant environment. Delayed notification of the outbreak to public health authorities may have contributed to outbreak size and duration.


Assuntos
Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/transmissão , Surtos de Doenças , Doenças Transmitidas por Alimentos/epidemiologia , Gastroenterite/epidemiologia , Norovirus/isolamento & purificação , Adulto , Animais , Infecções por Caliciviridae/virologia , Estudos de Casos e Controles , Diarreia/epidemiologia , Diarreia/virologia , Inglaterra/epidemiologia , Fezes/virologia , Feminino , Manipulação de Alimentos , Doenças Transmitidas por Alimentos/virologia , Gastroenterite/virologia , Humanos , Masculino , Norovirus/genética , Razão de Chances , Ostreidae/microbiologia , Restaurantes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco , Vômito/epidemiologia , Vômito/virologia
6.
Oecologia ; 170(2): 341-53, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22526940

RESUMO

Climate change is driving species range shifts worldwide. However, physiological responses related to distributional changes are not fully understood. Oceanographers have reported an increase in ocean temperature in the northwest Iberian Peninsula that is potentially related to the decline in some cold-temperate intertidal macroalgae in the Cantabrian Sea, namely Fucus serratus. Low tide stress could also play a role in this decline. We performed one mensurative (in situ) and two manipulative (in culture) experiments designed to evaluate the interactive effects of some physical factors. The first experiment analysed field response to low tide stress in marginal (mid-Cantabrian Sea and northern Portugal) versus central (Galicia) populations of F. serratus. Then a second experiment was performed that utilized either harsh or mild summer conditions of atmospheric temperature, irradiance, humidity, and wind velocity to compare the responses of individuals from one marginal and one central population to low tide stress. Finally, the combined effect of sea temperature and the other factors was evaluated to detect interactive effects. Changes in frond growth, maximal photosynthetic quantum yield (F(v)/F(m)), temperature, and desiccation were found. Three additive factors (solar irradiation, ocean and air temperatures) were found to drive F. serratus distribution, except under mildly humid conditions that ameliorated atmospheric thermal stress (two additive factors). Mid-Cantabrian Sea temperatures have recently increased, reaching the inhibitory levels suggested in this study of F. serratus. We also expect an additive secondary contribution of low tide stress to this species decline. On the northern Portugal coast, ocean warming plus low tide stress has not reached this species' inhibition threshold. No significant differential responses attributed to the population of origin were found. Mechanistic approaches that are designed to analyse the interactive effects of physical stressors may improve the levels of confidence in predicted range shifts of species.


Assuntos
Fucus/crescimento & desenvolvimento , Aquecimento Global , Estresse Fisiológico , Biologia Marinha , Dinâmica Populacional , Portugal , Estações do Ano , Temperatura
7.
J Mater Sci Mater Med ; 23(3): 657-66, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22271277

RESUMO

This study reports on the biocompatibility of 316 LVM steel blasted with small and rounded ZrO(2) particles or larger and angular shaped Al(2)O(3) particles. The effect of blasting on the in vitro corrosion behavior and the associated ion release is also considered. Surface of Al(2)O(3) blasted samples was rougher than that of ZrO(2) blasted samples, which was also manifested by a higher surface area. Compared to the polished alloy, blasted steels exhibited a lower corrosion resistance at the earlier stages of immersion, particularly when using Al(2)O(3) particles. With increasing immersion time, blasted samples experienced an improvement of the corrosion resistance, achieving impedance values typical of passive alloys. Blasting of the alloy led to an increase in Fe release and the leaching of Ni, Mn, Cr and Mo. On all surfaces, ion release is higher during the first 24 h exposure and tends to decrease during the subsequent exposure time. Despite the lower corrosion resistance and higher amount of ions released, blasted alloys exhibit a good biocompatibility, as demonstrated by culturing osteoblastic cells that attached and grew on the surfaces.


Assuntos
Materiais Biocompatíveis , Aço Inoxidável , Corrosão , Propriedades de Superfície
8.
J Mater Sci Mater Med ; 22(4): 1005-14, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21437641

RESUMO

Commercial 316 LVM austenitic stainless steel samples have been coated by immersion in a bath of molten Al-12.6%Si alloy for 120 s. The coating consists of the Al(12)(Fe,Cr)(3)Si(2) intermetallic. In vitro corrosion behaviour has been evaluated in the Ringer's solution by means of potentiodynamic curves and electrochemical impedance spectroscopy. The results reveal that the coated specimens exhibit lower susceptibility to localised corrosion with respect to the substrate. XPS analysis suggests that the ennoblement of the pitting potential is due to the formation of a chromium oxyhydroxide containing passive layer. The intermetallic coating shows a good biocompatibility, as demonstrated by culturing human mesenchymal stem cells isolated from bone marrow which attached, grew and differentiated to the osteoblastic lineage to a similar extent on coated and bare steels. In summary, this study proposes a method that generates Ni-free coatings of the stainless steel with useful properties for biomedical applications.


Assuntos
Alumínio/química , Materiais Biocompatíveis/química , Níquel/química , Silício/química , Aço Inoxidável/química , Células da Medula Óssea/citologia , Cromo/química , Corrosão , Eletroquímica/métodos , Temperatura Alta , Humanos , Hidróxidos/química , Teste de Materiais , Osteoblastos/citologia , Espectroscopia Fotoeletrônica , Espalhamento de Radiação
9.
Euro Surveill ; 14(27)2009 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-19589330

RESUMO

An outbreak of influenza A(H1N1)v was confirmed in May and June 2009 in a boarding school in South East England involving 102 symptomatic cases with influenza-like illness. Influenza A(H1N1)v infection was laboratory-confirmed by PCR in 62 pupils and one member of staff.


Assuntos
Surtos de Doenças/estatística & dados numéricos , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/prevenção & controle , Antivirais/administração & dosagem , Inglaterra/epidemiologia , Feminino , Humanos , Influenza Humana/epidemiologia , Influenza Humana/transmissão , Masculino , Oseltamivir/administração & dosagem , Reação em Cadeia da Polimerase , Instituições Residenciais , Instituições Acadêmicas , Sorotipagem
10.
J Biomed Mater Res A ; 81(2): 334-46, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17120220

RESUMO

Oxidation of Ti6Al4V at 500 degrees C for 1 h in air results in the formation of an outer ceramic layer that improves osteoblast behavior and decreases Ti and Al ion release. In this work, alumina blasted Ti6Al4V alloy has been thermally treated and its in vitro biocompatibility has been assessed. Roughness of the blasted alloy was not found significantly altered after heat treatment while chemical surface analysis indicated an increase in stable TiO(2) and Al(2)O(3) oxides. Cell attachment, spreading, cytoskeleton organization as well as cell proliferation, viability, and procollagen I peptide secretion of human primary osteoblasts, impaired on alumina blasted Ti6Al4V, were found to be greatly enhanced on the thermally oxidized blasted alloy. Other informative markers of the osteoblastic phenotype such as alkaline phosphatase, osteocalcin, osteoprotegerin, and mineralized nodule formation were evaluated and indicated that osteoblasts responded at the same extent on untreated and thermally treated blasted alloys. Taken together, our in vitro results indicate that thermal oxidation of alumina blasted Ti6Al4V may favor successful osseointegration by promoting early interactions of osteoblastic cells and the modified surface alloy.


Assuntos
Materiais Biocompatíveis/química , Osteoblastos/citologia , Titânio/química , Actinas/metabolismo , Fosfatase Alcalina/metabolismo , Ligas/química , Adesão Celular , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Temperatura Alta , Humanos , Técnicas In Vitro , Teste de Materiais , Microscopia Eletrônica de Varredura , Osteoblastos/metabolismo , Osteocalcina/metabolismo , Osteoprotegerina/metabolismo , Oxirredução , Fragmentos de Peptídeos/metabolismo , Pró-Colágeno/metabolismo , Ligante RANK/metabolismo , Análise Espectral , Propriedades de Superfície , Raios X
11.
Biomed Mater ; 12(1): 015025, 2017 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-28211364

RESUMO

Polylactic acid/Mg composites have been recently proposed for biodegradable osteosynthesis devices because, with regards to the neat polymer, they combine an enhanced biocompatibility and bioactivity with better mechanical properties, particularly creep strength. A question still arises about their bacterial behavior. For this purpose, composites of poly-L-D-lactic acid (PLDA) loaded with 1 and 10 wt.% of Mg microparticles were evaluated using Staphylococcus epidermidis, with special emphasis on the study of bacterial adhesion and biofilm formation. During biofilm formation the bacteria viability of the composites decreased up to 65.3% with respect to PLDA. These antibacterial properties do not compromise the cytocompatibility of the material as the composites enhanced the viability of mesenchymal stem cells and their osteogenic commitment. These findings provide an important added value to the biodegradable and biocompatible PLDA/Mg composites for the manufacture of osteosynthesis devices.


Assuntos
Implantes Absorvíveis , Antibacterianos/química , Antibacterianos/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Magnésio/química , Magnésio/farmacologia , Poliésteres/química , Poliésteres/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Fixação Interna de Fraturas , Humanos , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/fisiologia
12.
Transplant Proc ; 49(6): 1444-1448, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28736021

RESUMO

BACKGROUND: Hematopoietic stem cell transplantation (HSCT) has been used as treatment in different hematologic and solid malignancies. The aim of this study was to describe the frequency of infectious complications, microbiology, and outcome in patients undergoing HSCT in Mexico during the pre-engraftment period and the impact on mortality rates at 12 months. METHODS: We conducted a retrospective study of all hematologic malignancies that received HSCT from January 2009 and December 2014, at an oncology reference center. RESULTS: We included 210 patients: 144 autologous (69%) and 66 allogeneic HSCT (31%). There were 184 infections documented in 109 patients; incidence rate was 47.2 per 1000 neutropenia/days and 22.4 per 1000 hospitalization/days. The main infections reported were pneumonia (n = 40, 19%), bloodstream infections (n = 36, 17.1%), and central line-associated bloodstream infections (n = 28, 13.3%). There were 110 bacteria isolated, 31 were multidrug-resistant (26 were extended-spectrum beta-lactamase; Escherichia coli). There were 25 disseminated or complicated viral infections and 20 invasive fungal diseases. Fourteen patients died in the first 30 days (all related to the infectious process). In multivariate analysis leukemia, more than 2 chemotherapy regimens before transplant and pneumonia were related to 12-month mortality rates. CONCLUSIONS: Even though infectious processes are frequent in patients with HSCT, multidrug-resistant bacteria were not as frequent as supposed; however, when these microorganisms are involved, mortality rate is increased. It is important to be alert that patients with pneumonia have a significantly increased mortality risk in the first year.


Assuntos
Infecções Bacterianas/epidemiologia , Farmacorresistência Bacteriana Múltipla , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Neutropenia/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Adulto , Idoso , Infecções Bacterianas/microbiologia , Feminino , Neoplasias Hematológicas/microbiologia , Neoplasias Hematológicas/terapia , Humanos , Incidência , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Neutropenia/microbiologia , Complicações Pós-Operatórias/microbiologia , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
13.
J Orthop Res ; 24(1): 46-54, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16419968

RESUMO

The purpose of the current study was to evaluate the effects of alumina particles on secretion of several cytokines involved in bone resorption in cocultures of macrophages and osteoblasts. To distinguish the contribution of each individual cell type, we have established a heterologous in vitro system that makes use of mouse J774 cells and primary cultured human osteoblasts. J744 cells decreased the production of TNF-alpha when they were cocultured with osteoblasts. Treatment of J744 cells with alumina particles increased TNF-alpha secretion, but the induction was lower when cells were cocultured with osteoblasts. Secretion of IL-6 by J744 cells was very low, and increased in the presence of osteoblasts. Alumina particles were only able to stimulate the release of IL-6 by J744 cells when cells were cocultured with osteoblasts. On the other hand, incubation of osteoblasts with alumina particles enhanced the release of IL-6 and GM-CSF. Coculturing osteoblasts with J744 cells induced them to release IL-6 and GM-CSF, and treatment with alumina further increased the secretion of both mediators by osteoblasts. According to these in vitro results, it seems rather plausible that alumina particles are able to initiate an inflammatory response in vivo.


Assuntos
Óxido de Alumínio/farmacologia , Citocinas/metabolismo , Macrófagos/fisiologia , Osteoblastos/fisiologia , Idoso , Animais , Materiais Biocompatíveis/farmacologia , Técnicas de Cocultura , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Humanos , Interleucina-6/metabolismo , Macrófagos/efeitos dos fármacos , Camundongos , Pessoa de Meia-Idade , Osteoblastos/efeitos dos fármacos , Tamanho da Partícula , Fator de Necrose Tumoral alfa/metabolismo
14.
J Biomed Mater Res A ; 77(3): 608-17, 2006 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-16506177

RESUMO

We have evaluated the in-vitro biocompatibility of Ti6Al4V alloy coated by plasma spraying with an identical alloy. These surfaces are widely used in cementless prosthetic components, although osteoblasts behavior on this treated alloy has not been evaluated to date. Cross sectional examination revealed a thick and rough coating of identical composition without sign of delamination. Within the coating, small discontinuities and nonconnected pores were observed. Osteoblast response was evaluated by assessing cell adhesion, proliferation, and differentiation of primary cultures of human osteoblastic cells. Compared to the polished alloy, osteoblast adhesion measured as cell attachment and actin network reorganization was delayed on the plasma-sprayed surface. Cell proliferation and viability were also impaired on the rough surface. Several informative markers of osteoblastic differentiation such as procollagen I peptide, alkaline phosphatase, osteocalcin, osteoprotegerin, and mineralized nodule formation were evaluated and indicated that the plasma-sprayed alloy favored a more differentiated phenotype than polished alloy. Taken together, our in vitro results indicate that successful osseointegration of plasma spraying of Ti6Al4V with an identical alloy is mediated by modulation of osteoblastic differentiation and mineralization.


Assuntos
Materiais Revestidos Biocompatíveis , Teste de Materiais , Osteoblastos , Titânio , Idoso , Ligas , Células Cultivadas , Humanos
15.
J Biomed Mater Res A ; 77(2): 220-9, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16392123

RESUMO

Thermal oxidation treatments of Ti6Al4V, at 500 and 700 degrees C, for 1 h result in the formation of an outer "ceramic" layer of rutile, which enhances osteoblast response. In the present study, we have measured in vitro Ti and Al ion release from Ti64 alloy in the as-received state and after thermal oxidation treatments at 500 or 700 degrees C, to culture medium under standard cell-culture conditions. Concentrations of both Ti and Al released from both thermal oxidation treatments were lower than from polished alloy. Al was released from the treated or untreated surfaces in substantially lower extent than Ti. Titanium and aluminium ions affected primary human osteoblast proliferation, metabolic activity, and differentiation in a dose-dependent manner. Treatments with individual Ti or Al metal ions in similar concentration ranges than released from the surfaces did not alter osteoblast response, which also remained unaffected after treatments with combinations of Ti plus Al applied in the proportional relations than detected in ion-release experiments. We then selected higher concentrations of Ti that impaired osteoblast proliferation and differentiation, while the proportional lower concentrations of Al did not alter osteoblast behavior. In spite of its inert character, it was found that Al significantly enhanced the deleterious effect of Ti on osteoblast differentiation. Therefore, thermal oxidation treatments of Ti6Al4V alloy may improve the biocompatibility of the alloy by reducing both Ti and Al release, and thus attenuating ion-mediated interference with osteoblast differentiation.


Assuntos
Alumínio/metabolismo , Osteoblastos/metabolismo , Titânio/metabolismo , Idoso , Ligas , Alumínio/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Biomarcadores/metabolismo , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Humanos , Íons/química , Íons/metabolismo , Teste de Materiais , Osteoblastos/citologia , Soluções/química , Titânio/química
16.
J Biomed Mater Res A ; 73(1): 97-107, 2005 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-15704115

RESUMO

We have recently reported that thermal oxidation treatments of Ti6Al4V at 500 degrees and 700 degrees C for 1 h result in the formation of an outer "ceramic" layer of rutile that do not decrease the high in vitro corrosion resistance of the alloy. In the present work, surface roughness was measured and found marginally increased as a consequence of oxidation of the alloy at 700 degrees C, but not at 500 degrees C. We have evaluated the biocompatibility of the oxidized surfaces, by assessing cell adhesion, proliferation, and differentiation of primary cultures of human osteoblastic cells. Compared with polished alloy, both thermal treatments increased osteoblast adhesion measured as cell attachment, beta1 integrin and FAK-Y397 expression, as well as cytoskeletal reorganization. Compared with treatment at 500 degrees C, thermal oxidation at 700 degrees C enhanced cell adhesion. Treatment at 700 degrees C transiently impaired cell proliferation and viability, which were not altered in alloys oxidized at 500 degrees C. Several markers of osteoblastic differentiation such as procollagen I peptide, alkaline phosphatase, osteocalcin, and mineralized nodule formation were found either unaffected or differentially increased by alloys treated either at 500 degrees or 700 degrees C. In addition, thermal oxidation at 700 degrees C also increased osteoprotegerin secretion. Taken together, our results indicate that thermal oxidation treatments at 500 degrees or 700 degrees C for 1 h improve the in vitro biocompatibility of Ti6Al4V.


Assuntos
Osteoblastos/efeitos dos fármacos , Titânio/química , Titânio/farmacologia , Actinas/metabolismo , Idoso , Ligas , Osso e Ossos/citologia , Calcificação Fisiológica/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Quinase 1 de Adesão Focal , Proteína-Tirosina Quinases de Adesão Focal , Humanos , Cadeias beta de Integrinas/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Oxirredução , Proteínas Tirosina Quinases/metabolismo , Temperatura
17.
J Pediatr Urol ; 11(1): 37.e1-6, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25748631

RESUMO

BACKGROUND: Ureteral tapering and reimplantation is an established treatment for persistent or progressive primary obstructive megaureter (POM) but may result in complications and morbidity. Use of a less invasive technique involving endoscopic balloon dilation appears very interesting. OBJECTIVE: The objective of this report is to determine if endoscopic balloon dilation for POM is effective in the long term as well as to assess complications of the procedure. MATERIAL AND METHODS: A retrospective review was done on 19 patients and 20 ureters treated with the endoscopic balloon dilation by POM from June 2000 to February 2010. Surgery was performed solely in those cases in which there was persistence of obstruction in the renogram along with one or all of the following conditions: impairment of the differential renal function <40%, worsening of the renal pelvic dilation, febrile UTI in spite of antibiotic prophylaxis or renal calculi. The patients comprised 16 boys and 3 girls with a mean age at surgery of 17 months (range 1-44 months). Ten cases were left sided, eight right sided, and one bilateral. Under endoscopic and fluoroscopic guidance, a 3-5 Fr dilating balloon was inflated to 12-14 atm, or until disappearance of the stenotic obstructive area. A double J stent was positioned and withdrawn 2 months later. Follow-up recorded the presence of symptoms, number of reintervention procedures registered, and included renal ultrasound and MAG-3 renogram. RESULTS: There were no perioperative complications. Eighteen ureters showed a non-obstructive pattern on MAG-3 renogram after the first endoscopic dilation, representing a 90% success rate. One case required a second dilation, which proved successful and two cases of recurrent lithiasis required ureterotomy without instances of obstruction. 2 patients had a febrile UTI and a vesicoureteral reflux was diagnosed in one. Renal function was preserved in 95% of patients. The mean follow-up was 6.9 years (range 3.9-13.3 years). One patient was lost after the procedure. DISCUSSION: In an era of minimally invasive techniques, the search for less invasive procedures for treatment of POM has resulted in a variety of surgical options. Angulo et al., in 1998 and our group described the first POM treatment with endoscopic balloon dilation, which is believed to be a definitive, less invasive, and safe treatment. Furthermore, should an endoscopic approach fail, reimplant surgery can be performed. Few publications have reported short series with good results in the short and medium term. Torino et al. presented five cases in children aged less than 1 year, none of these showed evidence of obstruction. García-Aparicio et al. presented a series of 13 patients treated with a success rate of 84.6%. Christman et al. added laser incision in cases of narrowed ureteral segment 2-3 cm long and used double stenting. Good outcomes were presented in 71%. Romero et al. reported improvement of drainage within the first 18 months after treatment in 69% of patients. The potential de novo onset of vesicoureteral reflux may be the source of some controversy. We consider that dilation does not significantly alter the antireflux mechanism. In VCUG is not systematically performed because it is an invasive test. This restricts the conclusions that can be drawn from our findings. Nevertheless, some groups continue to systematically perform VCUG. CONCLUSIONS: Endoscopic balloon dilation for POM is a safe, feasible, and less invasive procedure that shows good outcomes on long-term follow-up. However, multicenter studies and prospective trials should be encouraged to provide more definitive evidence on its benefits.


Assuntos
Endoscopia , Ureter/anormalidades , Obstrução Ureteral/diagnóstico , Obstrução Ureteral/cirurgia , Cateterismo Urinário , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Masculino , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Obstrução Ureteral/etiologia
18.
Enferm. univ ; 17(2): 202-219, abr.-jun. 2020. tab
Artigo em Espanhol | LILACS-Express | LILACS, BDENF - Enfermagem | ID: biblio-1345985

RESUMO

Resumen Introducción: El ser cuidador primario informal de un paciente con indicación médica de trasplante de células progenitoras hematopoyéticas puede tener consecuencias negativas en su salud mental y calidad de vida. Objetivo: Describir las intervenciones psicológicas disponibles para el cuidador primario de pacientes sometidos a trasplante de células hematopoyéticas. Metodología: Se realizó una búsqueda sistematizada de los últimos 10 años con los términos MeSH: psychotherapy AND caregive AND stem cell transplantation en las principales bases de datos médicas y de psicología, para su análisis se empleó la estrategia: Problema, Intervención, Comparación y Outcomes (PICO). Resultados: Se identificaron 122 artículos, de ellos diez cumplieron los criterios de inclusión. Las intervenciones provenían de profesionales de enfermería o trabajo social; el 50% incluyó diadas (paciente y cuidador primario), mostraron una tendencia de duración corta, enfocada al periodo posterior al trasplante. Se basan en el entrenamiento en solución de problemas, manejo de estrés, atención plena y expresión emocional. Las intervenciones lograron la disminución de la depresión, ansiedad y estrés en el cuidador; pero no alcanzaron permanencia en la significancia estadística de dichos restablecimientos. Discusión: De acuerdo con lo observado en las publicaciones y por su impacto positivo en la salud mental, se recomienda la implementación de intervenciones psicológicas en cuidadores de pacientes con trasplante de células progenitoras hematopoyéticas. Conclusión: El apoyo psicológico brindado al cuidador generalmente es de profesionales de la salud que no pertenecen al área de la psicología, con resultados clínicos favorables en las etapas más críticas de su estado mental.


Abstract Introduction: Being an informal primary healthcare provider of a patient who undergoes hematopoietic progeny cells transplantation can have adverse consequences on mental health and the quality of life. Objective: To describe the available psychological interventions for the primary healthcare provider of patients undergoing hematopoietic cells transplantations. Methodology: A systematized search of the last 10 years using the MeSH terms psychotherapy AND caregiver AND stem cell transplantation was conducted on the main medical and psychological databases. The analysis strategy followed the PICO scheme (Problem, Intervention, Comparison, Outcomes). Results: 122 articles were identified, and 10 of them fulfilled the inclusion criteria. The interventions were related to nursing or social work professionals. 50% described patient-healthcare provider dyads with short interventions focused on the post-transplantation period. Discussion: According to what has been observed in the publications and due to its positive impact on mental health, the implementation of psychological interventions is recommended in caregivers of patients who underwent hematopoietic stem cell transplantation. Conclusion: The psychological support provided to the caregiver comes mainly from health professionals who do not belong to the area of psychology, with favorable clinical results in the most critical periods for their mental state.


Resumo Introdução: Ser cuidador primário informal de um paciente sometido a transplante de células progenitoras hematopoiéticas pode ter consequências negativas na saúde mental e na qualidade de vida. Objetivo: Descrever as intervenções psicológicas disponíveis para o cuidador primário de pacientes sometidos a transplante de células hematopoiéticas. Metodologia: Realizou-se uma busca sistematizada dos últimos 10 anos com os termos MeSH: psychotherapy AND caregive AND stem cell transplantation nas principais bases de dados médicas e de psicologia, para sua análise realizou-se a estratégia: Problema, Intervenção, Comparação e Outcomes (PICO). Resultados: Identificaram-se 122 artigos, dos quais, dez cumpriram os critérios de inclusão. As intervenções provinham de profissionais em enfermagem ou trabalho social; o 50% incluiu díades (paciente e cuidador primário), mostraram uma tendência de duração curta, focalizada no período posterior ao transplante. Baseiam-se no treinamento em solução de problemas, manejo de estresse, atenção plena e expressão emocional. As intervenções conseguiram melhoras clínicas na diminuição da depressão, ansiedade e estresse no cuidador; mas não alcançaram permanência na significância estatística destes restabelecimentos. Discussão: Conforme o observado nas publicações e por seu impacto positivo na saúde mental, recomenda-se a implementação de intervenções psicológicas em cuidadores de pacientes para quem se indicou transplante de células progenitoras hematopoiéticas. Conclusão: O apoio psicológico oferecido ao cuidador vem de principalmente profissionais da saúde que não pertencem à área da psicologia, com resultados clínicos favoráveis nos períodos mais críticos para seu estado mental.

19.
Biomaterials ; 24(1): 19-26, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12417174

RESUMO

In this work, the influence of thermal oxidation treatments of Ti6Al4V at 500 degrees C and 700 degrees C for 1 h on the in vitro corrosion behaviour and osteoblast response is studied. The potential of these treatments, aimed to improve the wear surface performance as biomaterial, relies in the formation of an outer "ceramic" layer of rutile. The corrosion behaviour was evaluated in simulated human fluids by electrochemical impedance spectroscopy and anodic polarisation tests. The effect of these thermal oxidation treatments on osteoblastic behaviour was studied in primary cultures of human osteoblastic cells. Results show that thermal oxidation treatments do not decrease the high in vitro corrosion resistance of the Ti6Al4V alloy. Osteoblast adhesion studies indicate that thermal oxidation treatments do not impair the material biocompatibility. Moreover, the thermal oxidation at 700 degrees C enhances the in vitro osteoblastic cell attachment compared to the thermal oxidation at 500 degrees C.


Assuntos
Materiais Biocompatíveis/química , Titânio/química , Ligas/química , Adesão Celular , Células Cultivadas , Corrosão , Temperatura Alta , Humanos , Técnicas In Vitro , Teste de Materiais , Microscopia Eletrônica de Varredura , Osteoblastos/citologia , Oxirredução , Próteses e Implantes , Propriedades de Superfície , Difração de Raios X
20.
Biomaterials ; 22(8): 755-62, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11246943

RESUMO

The influence of two different sizes of polyethylene particles (< 30 and 20-200 microm) on osteoblastic function has been studied in primary human bone cell cultures. Cells were obtained from trabecular bone fragments of patients undergoing knee reconstructive surgery. On reaching confluency, cells were subcultured in three flasks: < 30 microm polyethylene particles were added to the first flask, 20-200 microm particles to the second flask and none to the third flask, which was the control. The resulting subcultures were incubated until confluence. Osteoblastic function was evaluated by assaying the secretion of osteocalcin, alkaline phosphatase, and C-terminal type I procollagen (PICP), with or without 1.25(OH)2D3 stimulation in the cell-conditioned medium. Adding < 30 microm polyethylene particles to these osteoblastic cell cultures increased the levels of osteocalcin secreted after 1,25(OH)2D3 stimulation. Treating stimulated or basal osteoblastic cultures with either polyethylene particle size did not affect alkaline phosphatase secretion. However, the addition of <30 microm polyethylene particles decreased PICP levels in the basal and stimulated cultures. A parallel series of osteoblastic cultures was treated with < 30 microm polyethylene particles and stimulated or not with 1,25(OH)2D3 to determine the effect on osteocalcin mRNA expression using RT-PCR amplification. Polyethylene particle-treated cultures had higher osteocalcin mRNA expression regardless of whether they had been stimulated with 1,25(OH)2D3 or not. We conclude that particle size affects the influence of polyethylene on osteoblastic function markers. Particles with a diameter of less than 30 microm increase osteocalcin expression and secretion.


Assuntos
Materiais Biocompatíveis/toxicidade , Osteoblastos/efeitos dos fármacos , Osteoblastos/fisiologia , Polietileno/toxicidade , Fosfatase Alcalina/metabolismo , Materiais Biocompatíveis/química , Calcitriol/farmacologia , Células Cultivadas , Meios de Cultivo Condicionados , Reação a Corpo Estranho/etiologia , Expressão Gênica/efeitos dos fármacos , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Osteoblastos/citologia , Osteocalcina/genética , Osteocalcina/metabolismo , Tamanho da Partícula , Fragmentos de Peptídeos/metabolismo , Polietileno/química , Pró-Colágeno/metabolismo , Falha de Prótese , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
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