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1.
Data Brief ; 50: 109607, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37823067

RESUMO

The data presented in this article were collected in the field at an experimental station in southern France under a Mediterranean climate. Experiments were conducted under three plastic walk-in tunnels used as blocks with organic farming practices over two successive years in a completely randomized design. The aim was to compare the intercropping of sweet pepper with basil, onion, lettuce, parsley or French bean to a sole crop of sweet pepper used as a control. The dataset provides information on cultural practices with details on inputs and working times used to estimate economic costs. The data also describe the climatic conditions under tunnels as well as the dynamics of soil nitrate concentration and water tension over time through treatments. Yields, economic benefits and the rates of products with visual defects are presented. In addition, some variables applied exclusively to sweet pepper crops, namely nitrate concentration in petiole sap, growth parameters, abundance of aerial pests and beneficials, incidence of root necrosis, arbuscular mycorrhizal fungi colonization rates and diversity in roots. The field dataset is made publicly available to allow free and easy access for the scientific and professional community to enable analysis and reuse. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

2.
Can Commun Dis Rep ; 43(1): 25-28, 2017 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-29770044

RESUMO

The advice contained in this document should be read in conjunction with relevant federal, provincial, territorial and local legislation, regulations, and policies. Recommended measures should not be regarded as rigid standards, but principles and recommendations to inform the development of guidance. This advice is based on currently available scientific evidence and adopts a precautionary approach where the evidence is lacking or inconclusive. It was approved for publication on December 5, 2016. It is subject to review and change as new information becomes available. The main changes to this version include additions to: Case load reported to date, Sarcoidosis-like disease as an Indicator, Whole Genome Sequencing effort, links to Provincial and Territorial Lab Services and Health Canada reporting.

3.
Parasitology ; 144(4): 527-535, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27894375

RESUMO

Four species of malaria parasite, Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae and Plasmodium knowlesi infect humans living in the Khanh Phu commune, Khanh Hoa Province, Vietnam. The latter species also infects wild macaque monkeys in this region. In order to understand the transmission dynamics of the three species, we attempted to detect gametocytes of the three species in the blood of infected individuals, and sporozoites in the salivary glands of mosquitoes from the same region. For the detection of gametocyte-specific mRNA, we targeted region 3 of pfg377, pvs25, pmg and pks25 as indicators of the presence of P. falciparum, P. vivax, P. malariae and P. knowlesi gametocytes, respectively. Gametocyte-specific mRNA was present in 37, 61, 0 and 47% of people infected with P. falciparum (n = 95), P. vivax (n = 69), P. malariae (n = 6) or P. knowlesi (n = 32), respectively. We found that 70% of mosquitoes that had P. knowlesi in their salivary glands also carried human malaria parasites, suggesting that mosquitoes are infected with P. knowlesi from human infections.


Assuntos
Culicidae/parasitologia , Malária/parasitologia , Plasmodium knowlesi , Adolescente , Adulto , Animais , Criança , Feminino , Humanos , Malária/epidemiologia , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Protozoário/genética , Vietnã/epidemiologia , Adulto Jovem
4.
J Thromb Haemost ; 6(10): 1655-62, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18662264

RESUMO

BACKGROUND: Warfarin is commonly prescribed for prophylaxis and treatment of thromboembolism after orthopedic surgery. During warfarin initiation, out-of-range International Normalized Ratio (INR) values and adverse events are common. METHODS: In orthopedic patients beginning warfarin therapy, we developed and prospectively validated pharmacogenetic and clinical dose refinement algorithms to revise the estimated therapeutic dose after 4 days of therapy. RESULTS: The pharmacogenetic algorithm used the cytochrome P450 (CYP) 2C9 genotype, smoking status, peri-operative blood loss, liver disease, INR values and dose history to predict the therapeutic dose. The R(2) was 82% in a derivation cohort (n = 86) and 70% when used prospectively (n = 146). The R(2) of the clinical algorithm that used INR values and dose history to predict the therapeutic dose was 57% in a derivation cohort (n = 178) and 48% in a prospective validation cohort (n = 146). In 1 month of prospective follow-up, the percent time spent in the therapeutic range was 7% higher (95% CI: 2.7-11.7) in the pharmacogenetic cohort. The risk of a laboratory or clinical adverse event was also significantly reduced in the pharmacogenetic cohort (Hazard Ratio 0.54; 95% CI: 0.30-0.97). CONCLUSIONS: Warfarin dose adjustments that incorporate genotype and clinical variables available after four warfarin doses are accurate. In this non-randomized, prospective study, pharmacogenetic dose refinements were associated with more time spent in the therapeutic range and fewer laboratory or clinical adverse events. To facilitate gene-guided warfarin dosing we created a non-profit website, http://www.WarfarinDosing.org.


Assuntos
Algoritmos , Artroplastia/métodos , Protocolos Clínicos/normas , Farmacogenética/métodos , Valor Preditivo dos Testes , Tromboembolia/prevenção & controle , Varfarina/administração & dosagem , Adulto , Idoso , Artroplastia/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pré-Medicação , Estudos Prospectivos , Fatores de Risco , Resultado do Tratamento , Varfarina/efeitos adversos
5.
Diabetologia ; 50(4): 824-32, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17310372

RESUMO

AIMS/HYPOTHESIS: This study examined the efficacy of supplemental L: -carnitine as an adjunctive diabetes therapy in mouse models of metabolic disease. We hypothesised that carnitine would facilitate fatty acid export from tissues in the form of acyl-carnitines, thereby alleviating lipid-induced insulin resistance. MATERIALS AND METHODS: Obese mice with genetic or diet-induced forms of insulin resistance were fed rodent chow +/- 0.5% L: -carnitine for a period of 1-8 weeks. Metabolic outcomes included insulin tolerance tests, indirect calorimetry and mass spectrometry-based profiling of acyl-carnitine esters in tissues and plasma. RESULTS: Carnitine supplementation improved insulin-stimulated glucose disposal in genetically diabetic mice and wild-type mice fed a high-fat diet, without altering body weight or food intake. In severely diabetic mice, carnitine supplementation increased average daily respiratory exchange ratio from 0.886 +/- 0.01 to 0.914 +/- 0.01 (p < 0.01), reflecting a marked increase in systemic carbohydrate oxidation. Similarly, under insulin-stimulated conditions, carbohydrate oxidation was higher and total energy expenditure increased from 172 +/- 10 to 210 +/- 9 kJ kg fat-free mass(-1) h(-1) in the carnitine-supplemented compared with control animals. These metabolic improvements corresponded with a 2.3-fold rise in circulating levels of acetyl-carnitine, which accounts for 86 and 88% of the total acyl-carnitine pool in plasma and skeletal muscle, respectively. Carnitine supplementation also increased several medium- and long-chain acyl-carnitine species in both plasma and tissues. CONCLUSIONS/INTERPRETATION: These findings suggest that carnitine supplementation relieves lipid overload and glucose intolerance in obese rodents by enhancing mitochondrial efflux of excess acyl groups from insulin-responsive tissues. Carefully controlled clinical trials should be considered.


Assuntos
Carnitina/uso terapêutico , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/tratamento farmacológico , Animais , Calorimetria/métodos , Carnitina/análogos & derivados , Carnitina/metabolismo , Carnitina/farmacologia , Ácidos Graxos/metabolismo , Teste de Tolerância a Glucose , Glicerol/metabolismo , Resistência à Insulina , Masculino , Espectrometria de Massas , Camundongos , Camundongos Obesos , Piruvato Desidrogenase (Lipoamida)/metabolismo , Complexo Vitamínico B/uso terapêutico
6.
J Colloid Interface Sci ; 299(2): 726-32, 2006 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-16554061

RESUMO

Synthesis of nanoparticles under restricted environment offered by water-in-oil (W/O) microemulsions provides excellent control over particle size and shape, and inter-particle spacing. Such an environment has been involved to synthesize silica nanoparticles with a CeO2 core, so-called CeO2@SiO2. Aqueous fluids made up of ceria nanoparticles with a size close to 5 nm have been used as the water phase component. The starting CeO2 sols and obtained CeO2@SiO2 nanoparticles have been characterized by dynamic light scattering (DLS), X-ray diffraction, scanning and transmission electron microscopy, and specific surface area measurements. The microemulsion process has been characterized by DLS. Preliminary results on CeO2@SiO2 thin films are presented.

7.
Biomed Mater Eng ; 12(1): 3-13, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11847405

RESUMO

Plasma-based sterilization is a promising alternative to the use of pure ethylene oxide (EO), for low-temperature clinical sterilization of medical instruments and devices. However, few studies have been published that evaluate its safety in terms of possible damage to materials, particularly polymers. The objective of this work was to evaluate polymer surface modifications induced by commercial plasma-based sterilizers, in comparison with pure EO: Samples from 5 polymer-based devices were subjected to 1, 5, and 10 sterilization cycles by Sterrad-100, Plazlyte, and pure EO. Surface analysis was carried out by X-ray photoelectron spectroscopy (XPS), dynamic contact angle measurements (DCA), and scanning electron microscopy (SEM). Surface oxidation and wettability changes were observed on all samples sterilized by plasma-based techniques, the degree of modifications depending on the sterilizer (Sterrad, Plazlyte) and the type of polymer. Drastic changes of surface appearance were also observed by SEM on PVC samples sterilized by Plazlyte and by pure EO. Possible repercussions on safety are discussed.


Assuntos
Óxido de Etileno/química , Polímeros/química , Poliuretanos/química , Esterilização/métodos , Adsorção , Plaquetas/metabolismo , Cateterismo , Desinfetantes , Microanálise por Sonda Eletrônica , Reutilização de Equipamento , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Oxigênio/metabolismo , Plasma/metabolismo , Cloreto de Polivinila/química , Esterilização/instrumentação , Propriedades de Superfície
8.
Ann Thorac Surg ; 72(3): 719-23; discussion 723-4, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11565647

RESUMO

BACKGROUND: Sternal wound infection remains a significant complication. We reviewed the incidence and the treatment of sternal wound infection after heart transplantation. METHODS: Of 226 patients who had a heart transplantation, 20 (8.8%) underwent postoperative wound debridement for superficial or deep sternal wound infection. The incidence and the survival of patients with sternal wound infection were analyzed. RESULTS: The incidence of sternal wound infection was similar among patients treated with four protocols of immunosuppressive drugs: cyclosporine and prednisone (0 of 22; 0%); cyclosporine, prednisone, and azathioprine (2 of 24; 8.3%); cyclosporine, prednisone, azathioprine, and antithymocyte globulin (15 of 139; 10.8%); and cyclosporine, prednisone, mycophenolate mofetil, and antithymocyte globulin (3 of 41; 7.3%) (p = 0.4). Six-month and 5-year survival of patients with sternal wound infection averaged 85% +/- 8% and 74% +/- 10% compared with 92% +/- 2% and 82% +/- 3% in patients without wound infection (p = 0.15). Patients with deep sternal wound infection, debridement, and reconstruction had a 5-year survival averaging 80% +/- 10%. CONCLUSIONS: The incidence of sternal wound infection remains similar between patients treated with the triple drug therapy. Surgical debridement and reconstruction can result in long-term survival after heart transplantation.


Assuntos
Transplante de Coração , Esterno/cirurgia , Infecção da Ferida Cirúrgica/cirurgia , Doença Aguda , Fatores Etários , Desbridamento , Feminino , Rejeição de Enxerto , Humanos , Imunossupressores/administração & dosagem , Masculino , Mediastinite/etiologia , Mediastinite/mortalidade , Pessoa de Meia-Idade , Análise Multivariada , Fatores de Risco , Infecção da Ferida Cirúrgica/mortalidade , Taxa de Sobrevida
9.
J Cardiovasc Surg (Torino) ; 42(3): 339-43, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11398029

RESUMO

BACKGROUND: Nosocomial candidemia is an important infection because of its increasing incidence and its high fatality rate. Candidiasis involves multiple risk factors. In this work, we study the degree of Candida colonization in cardiovascular surgical patients by taking into account the number of sites colonized and the density of growth. METHODS: Eleven (11) selected variables (age, sex, weight, diabetes, number of antibiotics, duration of antibiotics, length of hospitalization, length of stay in surgical intensive care unit, duration of surgery, temperature during surgery, and number of bypass) were considered to predict the perioperative variation of the colonization index (CI) by Candida in 131 cardiovascular surgical patients. These patients were divided into two groups: group A, coronary artery bypass grafting with extracorporeal circulation (72 patients) and group B, coronary artery bypass grafting without extracorporeal circulation (59 patients). RESULTS: One thousand and forty-eight fungal cultures were obtained from four different body sites and 162 isolated were identified. Candida albicans accounted for 74% of the strains in group A and 97% in group B. The statistical analysis (two-way anova) shows that group A patients with an increased CI have received significantly more antibiotics than those with a stable CI (1.50+/-0.83 vs 1.08+/- 0.40, p=0.0055). CONCLUSIONS: Epidemiological data obtained from this study show that coronary artery bypass grafting with extracorporeal circulation procedure is associated with an increase in the use of antibiotics and subsequently a higher risk a Candida colonization-infection.


Assuntos
Candidíase/etiologia , Ponte Cardiopulmonar , Ponte de Artéria Coronária , Infecção Hospitalar/etiologia , Complicações Pós-Operatórias/etiologia , Idoso , Antibacterianos/administração & dosagem , Antibacterianos/efeitos adversos , Candida/classificação , Candida/isolamento & purificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
10.
Micron ; 32(5): 497-507, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11163723

RESUMO

X-ray diffraction can be used for accurately determining not only classical, ordinary structures, but also modulated ones. For structures with weak modulations, the modulation induced satellite reflections are often hard to be observed by X-ray diffraction, but they appear clearly in electron diffraction. In these cases, X-ray diffraction will give only average structures whereas electron diffraction will yield information about the modulations. Sr(1.4)Ta(0.6)O(2.9) is a complex modulated compound with weak modulation and small modulated domains. Here we demonstrate the power of combining X-ray and electron crystallography for studying modulated structures on powders. The modulations of Sr(1.4)Ta(0.6)O(2.9) were determined from electron diffraction (SAED) and high resolution electron microscopy (HREM) images. With specially developed image processing techniques, the weak modulations were enhanced, facilitating the interpretation of HREM images in terms of atomic structure.

11.
Am J Respir Crit Care Med ; 162(6): 2079-86, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11112118

RESUMO

Although tuberculosis (TB) screening of immigrants has been conducted for over 50 yr in many industrialized countries, its cost- effectiveness has never been evaluated. We prospectively compared the yield and cost-effectiveness of two immigrant TB screening programs, using close-contact investigation and passive case detection. Study subjects included all immigration applicants undergoing radiographic screening, already arrived immigrants requiring surveillance for inactive TB, and close contacts of active cases resident in Montreal, Quebec, Canada, who were referred from June 1996 to June 1997 to the Montreal Chest Institute (MCI), a referral center specializing in respiratory diseases. For all subjects seen, demographic data, investigations, diagnoses, and therapy were abstracted from administrative data bases and medical charts. Estimated costs of detecting and treating each prevalent active case and preventing future active cases, based on federal and provincial health reimbursement schedules, were compared with the costs for passively diagnosed cases of active TB. Over a period of 1 yr, the three programs detected 27 cases of prevalent active TB and prevented 14 future cases. As compared with passive case detection, close-contact investigation resulted in net savings of $815 for each prevalent active case detected and treated and of $2,186 for each future active case prevented. The incremental cost to treat each case of prevalent active TB was $39,409 for applicant screening and $24,225 for surveillance, and the cost of preventing each case was $33,275 for applicants and $65,126 for surveillance. Close-contact investigation was highly cost effective and resulted in net savings. Immigrant applicant screening and surveillance programs had a significant impact but were much less cost effective, in large part because of substantial operational problems.


Assuntos
Busca de Comunicante/economia , Emigração e Imigração , Programas de Rastreamento/economia , Tuberculose Pulmonar/economia , Estudos de Coortes , Busca de Comunicante/métodos , Busca de Comunicante/estatística & dados numéricos , Análise Custo-Benefício/economia , Análise Custo-Benefício/estatística & dados numéricos , Emigração e Imigração/estatística & dados numéricos , Humanos , Cadeias de Markov , Programas de Rastreamento/métodos , Programas de Rastreamento/estatística & dados numéricos , Vigilância da População/métodos , Estudos Prospectivos , Quebeque , Sensibilidade e Especificidade , Resultado do Tratamento , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/transmissão
12.
Ann Thorac Surg ; 70(4): 1219-23, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11081874

RESUMO

BACKGROUND: The objective of the present study was to compare current results of prosthetic valve replacement following acute infective native valve endocarditis (NVE) with that of prosthetic valve endocarditis (PVE). Prosthetic valve replacement is often necessary for acute infective endocarditis. Although valve repair and homografts have been associated with excellent outcome, homograft availability and the importance of valvular destruction often dictate prosthetic valve replacement in patients with acute bacterial endocarditis. METHODS: A retrospective analysis of the experience with prosthetic valve replacement following acute NVE and PVE between 1988 and 1998 was performed at the Montreal Heart Institute. RESULTS: Seventy-seven patients (57 men and 20 women, mean age 48 +/- 16 years) with acute infective endocarditis underwent valve replacement. Fifty patients had NVE and 27 had PVE. Four patients (8%) with NVE died within 30 days of operation and there were no hospital deaths in patients with PVE. Survival at 1, 5, and 7 years averaged 80% +/- 6%, 76% +/- 6%, and 76% +/- 6% for NVE and 70% +/- 9%, 59% +/- 10%, and 55% +/- 10% for PVE, respectively (p = 0.15). Reoperation-free survival at 1, 5, and 7 years averaged 80% +/- 6%, 76% +/- 6%, and 76% +/- 6% for NVE and 45% +/- 10%, 40% +/- 10%, and 36% +/- 9% for PVE (p = 0.003). Five-year survival for NVE averaged 75% +/- 9% following aortic valve replacement and 79% +/- 9% following mitral valve replacement. Five-year survival for PVE averaged 66% +/- 12% following aortic valve replacement and 43% +/- 19% following mitral valve replacement (p = 0.75). Nine patients underwent reoperation during follow-up: indications were prosthesis infection in 4 patients (3 mitral, 1 aortic), dehiscence of mitral prosthesis in 3, and dehiscence of aortic prosthesis in 2. CONCLUSIONS: Prosthetic valve replacement for NVE resulted in good long-term patient survival with a minimal risk of reoperation compared with patients who underwent valve replacement for PVE. In patients with PVE, those who needed reoperation had recurrent endocarditis or noninfectious periprosthetic dehiscence.


Assuntos
Endocardite Bacteriana/cirurgia , Implante de Prótese de Valva Cardíaca , Valvas Cardíacas/transplante , Infecções Relacionadas à Prótese/cirurgia , Adulto , Idoso , Valva Aórtica/cirurgia , Endocardite Bacteriana/mortalidade , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/cirurgia , Complicações Pós-Operatórias/mortalidade , Falha de Prótese , Infecções Relacionadas à Prótese/mortalidade , Reoperação , Taxa de Sobrevida , Transplante Homólogo
13.
Eur J Cardiothorac Surg ; 18(3): 360-2, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10973549

RESUMO

We report the case of a patient with a left ventricular thrombus infected by Salmonella. The diagnosis was suspected from a gallium scan demonstrating an intense activity in the lower left parasternal area. A transesophageal echocardiogram confirmed a calcified left ventricular aneurysm with a mural thrombus containing pus and heterogeneous material. The patient underwent a successful left ventricular aneurysmectomy, thrombectomy and endocardial resection under cardiopulmonary bypass which brought the infection under control.


Assuntos
Cardiopatias/cirurgia , Ventrículos do Coração/cirurgia , Infecções por Salmonella , Salmonella/isolamento & purificação , Trombectomia/métodos , Trombose/cirurgia , Diagnóstico Diferencial , Ecocardiografia Transesofagiana , Cardiopatias/diagnóstico , Cardiopatias/microbiologia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Ventriculografia com Radionuclídeos , Infecções por Salmonella/diagnóstico , Infecções por Salmonella/microbiologia , Infecções por Salmonella/cirurgia , Trombose/diagnóstico , Trombose/microbiologia
14.
Clin Diagn Lab Immunol ; 7(3): 436-43, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10799458

RESUMO

The Association of Medical Laboratory Immunologists (AMLI) have developed a panel of antinuclear and anticytoplasmic antibody consensus sera that can be useful for enzyme immunoassay (EIA), Ouchterlony, and immunofluorescence assay methods. It was developed to assist in the evaluation of newly available EIA methods for the detection of autoantibodies. The panel of sera was evaluated in several clinical laboratories and a large number of laboratories owned by manufacturers of clinical autoantibody testing kits. The majority of sera performed well for the EIAs in both the clinical laboratories and the manufacturers' laboratories, but some samples had discrepant results. A major source of discrepancy is the current inability of the EIA results to be directly compared in a quantitative way as no standardization exists. The evaluation demonstrated lower sensitivity of detection by the Ouchterlony method. The limited evaluation of the sera with immunoblotting and Western blotting did not show good agreement with other methods. Further work must be done to standardize blotting methods prior to their use in routine clinical testing. The sera are now available to vendors and clinical laboratories for use in the detection of SS-A, SS-B, Sm, U1-RNP, Scl-70, Jo-1, double-stranded DNA, and centromere antibodies. The availability of the consensus sera will help evaluate and improve the EIA methods currently being used.


Assuntos
Anticorpos Antinucleares/análise , Anticorpos Antinucleares/imunologia , Técnicas Imunoenzimáticas/normas , Laboratórios/normas , Especificidade de Anticorpos , Reações Falso-Negativas , Reações Falso-Positivas , Humanos , Técnicas Imunoenzimáticas/métodos , Padrões de Referência , Sociedades Médicas , Organização Mundial da Saúde
15.
J Biomed Mater Res ; 51(1): 128-35, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10813754

RESUMO

The aim of this work was to investigate possible mechanisms of sterilization by low-temperature gas plasma: spore destruction by plasma is compared with etching of synthetic polymers. Bacillus subtilis spores were inoculated at the bottom of glass vials and subjected to different plasma gas compositions (O(2), O(2)/Ar, O(2)/H(2), CO(2), and O(2)/CF(4)), all known to etch polymers. O(2)/CF(4) plasma exhibited much higher efficacy than all other gases or gas mixtures tested, with a more than 5 log decrease in 7.5 min, compared with a 2 log decrease with pure oxygen. Examination by scanning electron microscopy showed that spores were significantly etched after 30 min of plasma exposure, but not completely. We speculate about their etch resistance compared with that of synthetic polymers on the basis of their morphology and complex coating structure. In contrast to so-called in-house plasma, sterilization by Sterrad(R) tended to increase the observed spores' size; chemical modification (oxidation), rather than etching, is believed to be the sterilization mechanism of Sterrad(R).


Assuntos
Bacillus subtilis/efeitos dos fármacos , Esterilização , Bacillus subtilis/ultraestrutura , Óxido de Etileno , Fluorocarbonos , Gases , Temperatura Alta , Microscopia Eletrônica de Varredura , Microesferas , Oxirredução , Oxigênio/química , Esporos Bacterianos/efeitos dos fármacos , Esporos Bacterianos/ultraestrutura
16.
Int J Epidemiol ; 28(3): 563-70, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10405865

RESUMO

BACKGROUND: To determine if the more interventionist approach of screening with the tuberculin test and chemoprophylaxis for high-risk positive reactors to control tuberculosis in long-term care facilities is cost-effective when compared to the case-finding and treatment approach. METHOD: A decision-analysis model was designed wherein systematic screening with the tuberculin skin test of all elderly patients newly admitted to facilities was compared to public health interventions restricted to investigation of cases and contacts with symptoms of tuberculosis after suspected exposure. Differences in life-years (LY), quality-adjusted life-years (QALY), cost per QALY and LY gained, annual cost per 1000 institutional patients were calculated in a health-care system perspective. RESULTS: In every situation analysed, screening and chemoprophylaxis were more effective. The cost per LY gained was within an acceptable range: $3437 per LY with a 0.6% nosocomial transmission rate and $7552 per LY when no nosocomial transmission was postulated. CONCLUSION: Screening plus chemoprophylaxis for high-risk reactors is more cost-effective than case-finding. This holds even when nosocomial transmission is assumed not to occur in facilities.


Assuntos
Técnicas de Apoio para a Decisão , Instituição de Longa Permanência para Idosos , Programas de Rastreamento/economia , Tuberculose/prevenção & controle , Idoso , Antituberculosos/economia , Antituberculosos/uso terapêutico , Canadá , Análise Custo-Benefício , Humanos , Assistência de Longa Duração , Cadeias de Markov , Anos de Vida Ajustados por Qualidade de Vida , Teste Tuberculínico , Tuberculose/tratamento farmacológico , Tuberculose/economia
17.
J Comp Neurol ; 411(2): 288-300, 1999 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-10404254

RESUMO

The dispositions and axonal trajectories of bulbospinal neurons in the pons and medulla of mouse and rat embryos is described from the earliest times these projections can be labelled retrogradely from the cervical spinal cord. Reticulospinal and vestibulospinal neurons are clustered into identifiable groups, each with a characteristic combination of spatial domain and axon trajectory. The various groups can be labelled retrogradely in a specific developmental sequence. The position of some groups shifts from medial to lateral with development, apparently through cell migration. These observations show that the basic regional organization of the reticulospinal and vestibulospinal projections is similar in mouse and rat and is already established during early stages of axon outgrowth.


Assuntos
Desenvolvimento Embrionário e Fetal , Camundongos Endogâmicos BALB C/embriologia , Neurônios/fisiologia , Ratos Sprague-Dawley/embriologia , Rombencéfalo/embriologia , Animais , Axônios/fisiologia , Padronização Corporal/fisiologia , Feminino , Lateralidade Funcional , Idade Gestacional , Bulbo/embriologia , Camundongos , Vias Neurais/embriologia , Neurônios/citologia , Ponte/embriologia , Gravidez , Ratos , Rombencéfalo/citologia , Medula Espinal/embriologia
18.
Biomaterials ; 20(7): 625-30, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10208404

RESUMO

The purpose of this study was to investigate in vitro the presence of apoptotic cell death after macrophage stimulation with different ceramic (Al2O3 and ZrO2) and high density polyethylene (HDP) particles. We also analyzed the effects of particle size, concentration, and composition. The J774 mouse macrophage cell line was exposed to commercial particles of different sizes (up to 4.5 microm) and concentrations (up to 500 particles per macrophage). Fluorescence microscopy and DNA laddering were used to investigate the presence of apoptosis in cell cultures after 24 h of incubation. Fluorescence microscopy of propidium iodide stained cells showed two characteristic morphological features that occur in apoptotic cells, namely nuclear condensation and heterogeneity of stain uptake. The effect of ceramic particles on apoptotic nuclear morphology was size- and concentration-dependent and reached a plateau above 150 particles per macrophage at 1.3 microm. With regards to composition, we did not find any difference in cell morphology between Al2O3 and ZrO2. Ceramic and HDP particles induced DNA fragmentation into oligonucleosomes as evidenced by DNA laddering, another characteristic of apoptosis. The induction of DNA laddering was size- and concentration-dependent whereas particle composition (Al2O3 vs. ZrO2 and Al2O3 vs. HDP) had no effect. In conclusion, our results demonstrated that ceramic and HDP particles induce macrophage apoptotic cell death in vitro and open doors for possible modulation of debris-induced periprosthetic osteolysis.


Assuntos
Óxido de Alumínio , Apoptose/efeitos dos fármacos , Materiais Biocompatíveis , Cerâmica , Macrófagos/efeitos dos fármacos , Polietilenos , Zircônio , Animais , Apoptose/fisiologia , Artroplastia de Quadril , Linhagem Celular , DNA/metabolismo , Dano ao DNA , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Microscopia de Fluorescência , Osteólise , Tamanho da Partícula
19.
Acta Crystallogr B ; 55(Pt 5): 677-682, 1999 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10927407

RESUMO

The structure of moganite-type phosphorus oxynitride quenched from high-pressure high-temperature conditions has been refined using neutron powder diffraction data. This moganite-type structure, space group I2/a, Z = 12, is slightly less distorted with respect to the Imab aristotype than is moganite (a monoclinic form of silica). A close topological relationship has been identified between the moganite-type and orthorhombic BeH(2) structures indicating that SiO(2), PON and BeH(2) all adopt structures belonging to the twinned-quartz-based group. This group represents another possible structure type for systems composed of corner-sharing AX(4) tetrahedra. Structures of this group are obvious candidates for intermediate phases between the cristobalite and quartz types.

20.
J Bone Joint Surg Br ; 81(3): 516-21, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10872377

RESUMO

Although the response of macrophages to polyethylene debris has been widely studied, it has never been compared with the cellular response to ceramic debris. Our aim was to investigate the cytotoxicity of ceramic particles (Al2O3 and ZrO2) and to analyse their ability to stimulate the release of inflammatory mediators compared with that of high-density polyethylene particles (HDP). We analysed the effects of particle size, concentration and composition using an in vitro model. The J774 mouse macrophage cell line was exposed to commercial particles in the phagocytosable range (up to 4.5 microns). Al2O3 was compared with ZrO2 at 0.6 micron and with HDP at 4.5 microns. Cytotoxicity tests were performed using flow cytometry and macrophage cytokine release was measured by ELISA. Cell mortality increased with the size and concentration of Al2O3 particles. When comparing Al2O3 and ZrO2 at 0.6 micron, we did not detect any significant difference at the concentrations analysed (up to 2500 particles per macrophage), and mortality remained very low (less than 10%). Release of TNF-alpha also increased with the size and concentration of Al2O3 particles, reaching 195% of control (165 pg/ml v 84 pg/ml) at 2.4 microns and 350 particles per cell (p < 0.05). Release of TNF-alpha was higher with HDP than with Al2O3 particles at 4.5 microns. However, we did not detect any significant difference in the release of TNF-alpha between Al2O3 and ZrO2 at 0.6 micron (p > 0.05). We saw no evidence of release of interleukin-1 alpha or interleukin-1 beta after exposure to ceramic or HDP particles.


Assuntos
Óxido de Alumínio/toxicidade , Cerâmica , Citocinas/metabolismo , Prótese de Quadril , Macrófagos/efeitos dos fármacos , Polietileno/toxicidade , Falha de Prótese , Zircônio/toxicidade , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Mediadores da Inflamação/metabolismo , Camundongos , Tamanho da Partícula , Fagocitose/efeitos dos fármacos
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