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1.
Epidemiol Infect ; 149: e1, 2020 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-33413705

RESUMO

Although testing is widely regarded as critical to fighting the COVID-19 pandemic, what measure and level of testing best reflects successful infection control remains unresolved. Our aim was to compare the sensitivity of two testing metrics - population testing number and testing coverage - to population mortality outcomes and identify a benchmark for testing adequacy. We aggregated publicly available data through 12 April on testing and outcomes related to COVID-19 across 36 OECD (Organization for Economic Development) countries and Taiwan. Spearman correlation coefficients were calculated between the aforementioned metrics and following outcome measures: deaths per 1 million people, case fatality rate and case proportion of critical illness. Fractional polynomials were used to generate scatter plots to model the relationship between the testing metrics and outcomes. We found that testing coverage, but not population testing number, was highly correlated with population mortality (rs = -0.79, P = 5.975 × 10-9vs. rs = -0.3, P = 0.05) and case fatality rate (rs = -0.67, P = 9.067 × 10-6vs. rs = -0.21, P = 0.20). A testing coverage threshold of 15-45 signified adequate testing: below 15, testing coverage was associated with exponentially increasing population mortality; above 45, increased testing did not yield significant incremental mortality benefit. Taken together, testing coverage was better than population testing number in explaining country performance and can serve as an early and sensitive indicator of testing adequacy and disease burden.


Assuntos
Teste para COVID-19/estatística & dados numéricos , COVID-19/epidemiologia , COVID-19/mortalidade , Saúde Global , Organização para a Cooperação e Desenvolvimento Econômico/estatística & dados numéricos , SARS-CoV-2 , Humanos
2.
Osteoporos Int ; 28(4): 1167-1178, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28083669

RESUMO

Our systematic review and meta-analysis of observational studies indicated that the use of antipsychotics was associated with a nearly 1.5-fold increase in the risk of fracture. First-generation antipsychotics (FGAs) appeared to carry a higher risk of fracture than second-generation antipsychotics (SGAs). INTRODUCTION: The risk of fractures associated with the use of antipsychotic medications has inconsistent evidence between different drug classes. A systematic review and meta-analysis was conducted to evaluate whether there is an association between the use of antipsychotic drugs and fractures. METHODS: Searches were conducted through the PubMed and EMBASE databases to identify observational studies that had reported a quantitative estimate of the association between use of antipsychotics and fractures. The summary risk was derived from random effects meta-analysis. RESULTS: The search yielded 19 observational studies (n = 544,811 participants) with 80,835 fracture cases. Compared with nonuse, use of FGAs was associated with a significantly higher risk for hip fractures (OR 1.67, 95% CI, 1.45-1.93), and use of second generation antipsychotics (SGAs) was associated with an attenuated but still significant risk for hip fractures (OR 1.33, 95% CI, 1.11-1.58). The risk of fractures associated with individual classes of antipsychotic users was heterogeneous, and odds ratios ranged from 1.24 to 2.01. Chlorpromazine was associated with the highest risk (OR 2.01, 95% CI 1.43-2.83), while Risperidone was associated with the lowest risk of fracture (OR 1.24, 95% CI 0.95-1.83). CONCLUSIONS: FGA users were at a higher risk of hip fracture than SGA users. Both FGAs and SGAs were associated with an increased risk of fractures, especially among the older population. Therefore, the benefit of the off-label use of antipsychotics in elderly patients should be weighed against any risks for fracture.


Assuntos
Antipsicóticos/efeitos adversos , Fraturas por Osteoporose/induzido quimicamente , Fraturas do Fêmur/induzido quimicamente , Fraturas do Quadril/induzido quimicamente , Humanos , Medição de Risco/métodos
4.
Clin Microbiol Infect ; 27(3): 435-442, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32325126

RESUMO

OBJECTIVES: This study sought to more fully elucidate the age-related trends in influenza mortality with a secondary goal of uncovering implications for treatment and prevention. METHODS: In this retrospective cohort analysis of data from the Nationwide Readmission Database, patients with influenza as a primary or secondary discharge diagnosis were separated into three age groups: 55 638 adults aged 20-64 years, 36 862 adults aged 65-79 years and 41 806 octogenarians aged ≥80 years. Propensity score (PS) weighting was performed to isolate age from other baseline differences. Crude and PS-weighted hazard ratios (HR) were calculated from the in-hospital all-cause 30-day mortality rate. Admission threshold bias was minimized by comparison of influenza with bacterial pneumonia mortality. RESULTS: Adults aged 20-64 years experienced higher in-hospital 30-day mortality compared with older adults aged 65-79 years (HR 0.66; 95% CI 0.55-0.79). Octogenarians had the highest mortality rate, but this was statistically insignificant compared with the adult cohort (HR 1.09; 95% CI 0.94-1.27). This trend was not explained by admission threshold bias: the 30-day mortality rate due to in-hospital bacterial pneumonia increased consistently with age (older adult HR 1.45; 95% CI 1.32-1.59; octogenarian HR 1.99; 95% CI 1.82-2.18). CONCLUSIONS: Adults aged 20-64 years and octogenarians were more likely to experience all-cause 30-day mortality during influenza hospitalization compared with older adults aged 65-79 years. These data emphasize the importance of prevention and suggest the need for more tailored treatment interventions based on risk stratification that includes age.


Assuntos
Hospitalização , Influenza Humana/epidemiologia , Influenza Humana/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Estados Unidos/epidemiologia , Adulto Jovem
5.
Leuk Res ; 21(11-12): 1087-96, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9444943

RESUMO

The effects of the administration of a 3-day course of 13-cis retinoic acid in combination with interferon a [RA/IFN] on the leukemia cells was measured in vivo in 43 patients with chronic myelogenous leukemia. The administration of RA/IFN was associated with a significant fall in the white blood cell count of patients with chronic-phase disease and with a fall in the percentage S-phase cells in CML patients regardless of the stage of their leukemia. In two thirds of the patients studied the administration of RA/IFN was also associated with an increase in marrow apoptosis. The cytokine combination also suppressed bcl-2 and myc expression in a minority of patients and such expression appears to be associated with response to a treatment regimen which includes RA/IFN. These studies are the first to directly assess the effects of the combination of RA/IFN on chronic myelogenous leukemia cells in vivo in patients. These effects, if seen in other malignant diseases, could account for the therapeutic benefit which has been associated with the administration of this combination of biological agents to patients with malignant disease.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Adulto , Idoso , Apoptose/efeitos dos fármacos , Medula Óssea/patologia , Feminino , Humanos , Interferon-alfa/administração & dosagem , Isotretinoína/administração & dosagem , Leucemia Mielogênica Crônica BCR-ABL Positiva/sangue , Contagem de Leucócitos/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-myc/biossíntese
6.
Leuk Res ; 22(5): 429-38, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9652729

RESUMO

The proliferation of acute myelogenous leukemia cells is dependent upon cytokine stimulation. Additionally, there is a body of literature which reports that leukemia cells produce GMCSF, IL6, and other cytokines. The study reported here, using an rt-multiplex polymerase method, determined the presence or absence of transcripts in freshly obtained AML cells for the following cytokine or cytokine-related genes: IL 1beta, IL1ra, TNF alpha, GMCSF, IL6, flt 3, and hSCF. This demonstrated that leukemia cell populations usually contain transcripts for IL1beta, TNF alpha, flt 3 and flt 3 ligand in vivo and that transcripts for the other cytokines only appear after the leukemia cells are processed in vitro. The presence of TNF alpha transcripts appears to be associated with resistance to remission induction therapy. Furthermore, the transcript profile of the leukemia cells can change during remission induction therapy. The data also demonstrate the assessment of cytokine production by leukemia cells after in vitro manipulation should not be extrapolated to the in vivo situation.


Assuntos
Citocinas/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Adulto , Idoso , Células da Medula Óssea/fisiologia , Feminino , Humanos , Leucemia Mieloide Aguda/terapia , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/análise , Indução de Remissão , Manejo de Espécimes , Transcrição Gênica , Fator de Necrose Tumoral alfa/genética
7.
Am J Med Genet ; 80(4): 418-22, 1998 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-9856575

RESUMO

Stable centromeric breakage in non-acrocentric chromosomes and balanced reciprocal translocation mosaicism are both rare events. We studied a family in which the mother had mosaicism for a balanced reciprocal translocation between chromosomes 10 and 16 which was associated with a break in chromosome 16 centromere alpha-satellite DNA ¿146,XX,t(10;16)(q11.2;q11.1) [29]/46,XX[25]¿. The derivative chromosome 16 contained only a very small amount of 16 alpha-satellite DNA while the derivative 10 contained all of the 10 alpha-satellite DNA as well as a large amount of the 16 alpha-satellite DNA. The same translocation was present in all cells in her son who was found prenatally to have trisomy 16 mosaicism ¿46,XY,t(10;16) (q11.2;q11.1)mat[22]/47,idem,+16[4]¿. Trisomy 16 cells were subsequently determined to be confined to the placenta. DNA polymorphism analyses in the family demonstrated maternal uniparental disomy for chromosome 16 in the diploid child. The child, at age 7 months, had minor facial anomalies similar to a previously reported case of maternal uniparental disomy for chromosome 16. In addition to illustrating several rare events, this family further demonstrated that substantial deletion of the centromeric alpha-satellite DNA does not impair centromere function and both mitotic and meiotic stability are retained in such cases.


Assuntos
Cromossomos Humanos Par 10/genética , Cromossomos Humanos Par 16/genética , Mosaicismo/genética , Placenta , Translocação Genética , Adulto , Centrômero/genética , Quebra Cromossômica , DNA/análise , DNA/genética , Feminino , Transtornos do Crescimento/genética , Transtornos do Crescimento/patologia , Humanos , Hibridização in Situ Fluorescente , Lactente , Cariotipagem , Masculino , Trissomia
8.
Am J Med Genet ; 80(5): 473-80, 1998 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-9880211

RESUMO

Trisomy 16, once thought to result uniformly in early pregnancy loss, has been detected in chorionic villus samples (CVS) from on-going pregnancies and was initially ascribed to a second, nonviable pregnancy. Prenatally detected trisomy 16 in CVS and its resolution to disomy has led to the reexamination of the viability of trisomy 16. This study evaluates 11 cases of mosaic trisomy 16 detected through second trimester amniocentesis. In 9 of the 11 cases, amniocenteses were performed in women under the age of 35 because of abnormal levels of maternal serum alpha-fetoprotein (MSAFP) or maternal serum human chorionic gonadotropin (MShCG). The other two amniocenteses were performed for advanced maternal age. Five of the 11 pregnancies resulted in liveborn infants, and six pregnancies were electively terminated. The liveborn infants all had some combination of intrauterine growth retardation (IUGR), congenital heart defects (CHD), or minor anomalies. Two of them died neonatally because of complications of severe congenital heart defects. The three surviving children have variable growth retardation, developmental delay, congenital anomalies, and/or minor anomalies. In the terminated pregnancies, the four fetuses evaluated by ultrasound or autopsy demonstrated various congenital anomalies and/or IUGR. Cytogenetic and fluorescent in situ hybridization studies identified true mosaicism in 5 of 10 cases examined, although the abnormal cell line was never seen in more than 1% of cultured lymphocytes. Placental mosaicism was seen in all placentas examined and was associated with IUGR in four of seven cases. Maternal uniparental disomy was identified in three cases. Mosaic trisomy 16 detected through amniocentesis is not a benign finding but associated with a high risk of abnormal outcome, most commonly IUGR, CHD, developmental delay, and minor anomalies. The various outcomes may reflect the diversity of mechanisms involved in the resolution of this abnormality. As 80% of these patients were ascertained because of the presence of abnormal levels of MSAFP or MShCG, the increased use of maternal serum screening should bring more such cases to clinical attention.


Assuntos
Cromossomos Humanos Par 16/genética , Mosaicismo/genética , Trissomia/genética , Amniocentese , Feminino , Humanos , Hibridização in Situ Fluorescente , Repetições de Microssatélites , Gravidez , Resultado da Gravidez/genética , alfa-Fetoproteínas
9.
Am J Med Genet ; 64(4): 539-45, 1996 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-8870919

RESUMO

Although fluorescent in situ hybridization (FISH) is rapidly becoming a part of clinical cytogenetics, no organization sponsors multi-center determinations of the efficacy of probes. We report on 23 laboratories that volunteered to provide slides and to use a probe for SNRPN and a control locus. Experiences with FISH for these laboratories during 1994 ranged from 0 to 645 utilizations (median = 84) involving blood, amniotic fluid and bone marrow. In an initial study of hybridization efficiency, the median percentage of metaphases from normal individuals showing two SNRPN and 2 control signals for slides prepared at each site was 97.0 (range = 74-100); for slides prepared by a central laboratory, it was 97.8 (range = 81.6-100). In a subsequent blind study, each laboratory attempted to score 5 metaphases from each of 23 specimens [8 with del(15) (q11.2-->q12) and 15 with normal 15 chromosomes]. Of 529 challenges, the correct SNRPN pattern was found in 5 of 5 metaphases in 457 (86%) and in 4 of 5 in 33 (6%). Ambiguous, incomplete or no results were reported for 32 (6%) challenges. Seven (1%) diagnostic errors were made including 6 false positives and 1 false negative: 1 laboratory made 3 errors, 1 made 2, and 2 made 1 each. Most errors and inconsistencies seemed due to inexperience with FISH. The working time to process and analyze slides singly averaged 49.5 minutes; slides processed in batches of 4 and analyzed singly required 36.9 minutes. We conclude that proficiency testing for FISH using an extensive array of challenges is possible and that multiple centers can collaborate to test probes and to evaluate costs.


Assuntos
Hibridização in Situ Fluorescente , Padrões de Referência , Humanos , Controle de Qualidade
10.
Am J Med Genet ; 76(4): 318-26, 1998 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9545096

RESUMO

Twenty-six laboratories used X and Y chromosome probes and the same procedures to process and examine 15,600 metaphases and 49,400 interphases from Phaseolus vulgaris-leucoagglutinin (PHA)-stimulated lymphocytes. In Part I, each laboratory scored 50 metaphases and 200 interphases from a normal male and a normal female from its own practice. In Part II, each laboratory scored 50 metaphases and 200 interphases on slides prepared by a central laboratory from a normal male and a normal female and three mixtures of cells from the male and female. In Part III, each laboratory scored 50 metaphases (in samples of 5, 10, 15, and 20) and 100 interphases (in samples of 5, 10, 15, 20, and 50) on new, coded slides of the same specimens used in Part II. Metaphases from male specimens were scored as 98-99% XY with no XX cells, and 97-98% of interphases were scored as XY with 0.04% XX cells. Metaphases from female specimens were scored as 96-97% XX with 0.03% XY cells, and 94-96% of interphases were scored as XX with 0.05% XY cells. Considering the data as a model for any probe used with fluorescence in situ hybridization (FISH), a statistical approach assessing the impact of analytical sensitivity on the numbers of observations required to assay for potential mosaicisms and chimerisms is discussed. The workload associated with processing slides and scoring 50 metaphases and 200 interphases using FISH averaged 27.1 and 28.6 minutes, respectively. This study indicates that multiple laboratories can test/develop guidelines for the rapid, efficacious, and cost-effective integration of FISH into clinical service.


Assuntos
Sondas de DNA , Hibridização in Situ Fluorescente/métodos , Interfase , Cromossomo X , Cromossomo Y , Citogenética/normas , Feminino , Humanos , Hibridização in Situ Fluorescente/instrumentação , Laboratórios/normas , Ativação Linfocitária , Linfócitos/citologia , Masculino , Metáfase , Fito-Hemaglutininas , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Carga de Trabalho
11.
Am J Med Genet ; 65(3): 190-6, 1996 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-9240742

RESUMO

Although fluorescent in situ hybridization (FISH) is rapidly becoming a part of clinical cytogenetics, no organization sponsors multicenter determinations of the efficacy of probes. We report on 23 laboratories that volunteered to provide slides and to use a probe for small nuclear ribonucleoprotein polypeptide N (SNRPN) and a control locus. Experiences with FISH for these laboratories during 1994 ranged from 0 to 645 utilizations (median = 84) involving blood, amniotic fluid, and bone marrow. In an initial study of hybridization efficiency, the median percentage of metaphases from normal individuals showing two SNRPN and two control signals for slides prepared at each site was 97.0 (range = 74-100); for slides prepared by a central laboratory, it was 97.8 (range = 81.6-100). In a subsequent blind study, each laboratory attempted to score 5 metaphases from each of 23 specimens [8 with del(15)(q11.2-->q12) and 15 with normal #15 chromosomes]. Of 529 challenges, the correct SNRPN pattern was found in 5 of 5 metaphases in 457 (86%) and in 4 of 5 in 33 (6%). Ambiguous, incomplete, or no results were reported for 32 (6%) challenges. Seven (1%) diagnostic errors were made, including 6 false positives and 1 false negative: 1 laboratory made 3 errors, 1 made 2, and 2 made 1 each. Most errors and inconsistencies seemed due to inexperience with FISH. The working time to process and analyze slides singly averaged 49.5 min; slides processed in batches of 4 and analyzed singly required 36.9 min. We conclude that proficiency testing for FISH by using an extensive array of challenges is possible and that multiple centers can collaborate to test probes and to evaluate costs.


Assuntos
Autoantígenos/genética , Cromossomos Humanos Par 15 , Hibridização in Situ Fluorescente/normas , Ribonucleoproteínas Nucleares Pequenas , Humanos , Metáfase , Controle de Qualidade , Padrões de Referência , Sensibilidade e Especificidade , Proteínas Centrais de snRNP
12.
Cancer Genet Cytogenet ; 104(1): 57-60, 1998 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-9648560

RESUMO

We report cytogenetic, fluorescence in situ hybridization (FISH), and molecular analysis in a case of Ph-negative chronic myelogenous leukemia patient with ABL/BCR fusion gene on chromosome 9 and a disparate FISH signal pattern using two commercially available bcr/abl probes (Vysis, Inc. and Oncor, Inc.). Cytogenetic analysis revealed a 46,XX normal female karyotype. FISH studies using Vysis LSI bcr/abl probe in interphase cells demonstrated a BCR/ABL fusion pattern, similar to that of m-BCR/ABL fusion found in acute lymphoblastic leukemia. However, examination of metaphases revealed the ABL/BCR fusion signal on one of the chromosomes 9, an ABL signal on the other chromosome 9, and two BCR signals of different sizes on each of the chromosomes 22. Subsequently, a FISH study with the Oncor major (M)-bcr/abl translocation probe confirmed the ABL/BCR fusion signal on chromosome 9 in addition to an ABL signal and a BCR signal located on chromosomes 9 and 22, respectively. Molecular studies (RT-PCR) revealed a rearrangement of the M-BCR region and expression of a chimeric bcr/abl mRNA of b3a2 configuration. This case suggests that it is imperative to have a full understanding of both the capabilities and the limitations of bcr/abl translocation probes and that FISH interphase signals should be confirmed on metaphase spreads for accurate diagnosis.


Assuntos
Cromossomos Humanos Par 9/genética , Proteínas de Fusão bcr-abl/genética , Hibridização in Situ Fluorescente/métodos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mieloide Crônica Atípica BCR-ABL Negativa/genética , Diagnóstico Diferencial , Feminino , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/epidemiologia , Leucemia Mieloide Crônica Atípica BCR-ABL Negativa/diagnóstico , Leucemia Mieloide Crônica Atípica BCR-ABL Negativa/epidemiologia , Pessoa de Meia-Idade , Variações Dependentes do Observador , Translocação Genética
13.
Cancer Genet Cytogenet ; 116(2): 97-104, 2000 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-10640140

RESUMO

Twenty-eight laboratories evaluated a new fluorescence in situ hybridization (FISH) strategy for chronic myeloid leukemia. In a three-part study, bcr/abl1 D-FISH probes were used to study bone marrow specimens. First, laboratories familiarized themselves with the strategy by applying it to known normal and abnormal specimens. Then, collectively the laboratories studied 20 normal and 20 abnormal specimens blindly and measured workload. Finally, each laboratory and two experts studied six serial dilutions with 98-0% abnormal nuclei. Using the reported normal cutoff of < 1% abnormal nuclei, participants reported no false-negative cases and 15 false-positive cases (1-6.6% abnormal nuclei). Results provided by participants for serial dilutions approximated the expected percentages of abnormal nuclei, but those from the experts exhibited greater precision. The clinical sensitivity, precision, nomenclature, workload, recommendations for training, and quality assurance in methods using D-FISH in clinical practice are discussed.


Assuntos
Técnicas de Laboratório Clínico/normas , Proteínas de Fusão bcr-abl/genética , Hibridização in Situ Fluorescente , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Medula Óssea/patologia , Corantes Fluorescentes , Humanos , Hibridização in Situ Fluorescente/instrumentação , Hibridização in Situ Fluorescente/métodos , Hibridização in Situ Fluorescente/normas , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Controle de Qualidade , Sensibilidade e Especificidade , Carga de Trabalho
14.
Leuk Lymphoma ; 41(3-4): 333-6, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11378545

RESUMO

Twenty five patients with AML who had neither a history of toxic exposure or myelodysplasia were treated with a remission induction regimen consisting of two pulses of chemotherapy separated by 96 hrs. Each pulse consisted of cytarabine 2gm/m(2) (at t=0 and t=12 hrs) with mitoxantrone [30mg/m(2) ] administered immediately after the second cytarabine administration. Amifostine was administered three times a week [on Monday, Wednesday, and Friday] until the outcome of therapy was known. This regimen induced complete remissions in 15 of 17 patients less than 70 years of age and in 5 of 8 patients older than 70 years.


Assuntos
Antineoplásicos/administração & dosagem , Leucemia Mieloide Aguda/tratamento farmacológico , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/normas , Estudos de Coortes , Citarabina/administração & dosagem , Citarabina/normas , Análise Citogenética , Esquema de Medicação , Humanos , Leucemia Mieloide Aguda/classificação , Leucemia Mieloide Aguda/genética , Pessoa de Meia-Idade , Mitoxantrona/administração & dosagem , Mitoxantrona/normas , Indução de Remissão , Fatores de Tempo , Resultado do Tratamento
15.
J Air Waste Manag Assoc ; 51(6): 885-94, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11417680

RESUMO

This work summarizes the results of numerical investigations and in situ measurements for turbulent combustion in a full-scale rotary kiln incinerator (RKI). The three-dimensional (3D) governing equations for mass, momentum, energy, and species, together with the kappa - epsilon turbulence model, are formulated and solved using a finite volume method. Volatile gases from solid waste were simulated by gaseous CH4 distributed nonuniformly along the kiln bed. The combustion process was considered to be a two-step stoichiometric reaction for primary air mixed with CH4 gas in the combustion chamber. The mixing-controlled eddy-dissipation model (EDM) was employed to predict the conversion rates of CH4, O2, CO2, and CO. The results of the prediction show that reverse flows occur near the entrance of the first combustion chamber (FCC) and the turning point at the entrance to the second combustion chamber (SCC). Temperature and species are nonuniform and are vertically stratified. Meanwhile, additional mixing in the SCC enhances postflame oxidation. A combustion efficiency of up to 99.96% can be achieved at approximately 150% excess air and 20-30% secondary air. Reasonable agreement is achieved between numerical predictions and in situ measurements.


Assuntos
Poluição do Ar/prevenção & controle , Modelos Teóricos , Eliminação de Resíduos , Incineração , Temperatura
16.
Clin Exp Immunol ; 145(3): 513-9, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16907921

RESUMO

Systemic lupus erythematosus (SLE) is a chronic, systemic autoimmune disease characterized by the loss of tolerance to self-antigen. Because it is currently not known if regulatory T (T(reg)) cells are involved in the pathogenesis, we determined the frequency of CD4(+)CD25(+) T cells and assayed the related gene expression levels in CD4(+)CD25(+) T cells isolated from both lupus mice (NZB/NZW F(1)) and normal control mice (DBA2/NZW F(1)). The results showed that the frequency of CD4(+)CD25(+) T cells in lupus mice was lower than that of normal mice. Except for the high expression level of interleukin (IL)-10 mRNA, CD4(+)CD25(+) T cells from lupus mice expressed normal forkhead box P3 (Foxp3) and transforming growth factor (TGF)-beta mRNA, and exerted suppressive functions. Furthermore, we depleted CD25(+) T(reg) cells of non-autoimmune mice with anti-CD25 antibody and broke their tolerance with apoptotic cell-pulsed dendritic cells for the follow-up of autoantibody levels. The mice in the CD25(+) cell-depleted group had higher titres of anti-double-strand/single-strand DNA antibodies than those of the isotype control antibody-treated group. These findings indicated that CD4(+)CD25(+) T cells might be involved in the regulatory mechanism of autoantibody production.


Assuntos
Autoanticorpos/imunologia , Linfócitos T CD4-Positivos/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Receptores de Interleucina-2/imunologia , Animais , Apoptose , Autoanticorpos/sangue , Células Dendríticas/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Fatores de Transcrição Forkhead/genética , Expressão Gênica , Terapia de Imunossupressão , Interleucina-10/genética , Camundongos , Camundongos Endogâmicos NZB , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Crescimento Transformador beta/genética
17.
Vox Sang ; 91(3): 270-4, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16958841

RESUMO

BACKGROUND AND OBJECTIVES: The demand for transfusions has increased rapidly in southern Taiwan. Between 1993 and 2003, requests for fresh-frozen plasma (FFP) in particular rose dramatically at Kaohsiung Medical University Hospital (KMUH). Transfusion orders were not tightly regulated, and inappropriate use of blood products was common. MATERIALS AND METHODS: We carried out a prospective analysis of transfusion requests from October 2003 to January 2004 at KMUH, and then repeated the audit for another 3-month period after the clinical faculty had undergone five sessions of education on transfusion guidelines. Later, our consultant haematologist applied computerized guidelines to periodic audits. RESULTS: A 5.2% decrease in inappropriate FFP usage followed the educational programme and a further 30% reduction took place after the application of computerized transfusion guidelines. With the guidelines and periodic audits, FFP transfusions decreased by 74.6% and inappropriate requests from 65.2% to 30%. CONCLUSIONS: Hospital policy, computerized transfusion guidelines and periodic audits greatly reduced inappropriate FFP transfusions. An educational campaign had a more limited effect.


Assuntos
Transfusão de Componentes Sanguíneos/estatística & dados numéricos , Auditoria Médica , Plasma , Guias de Prática Clínica como Assunto/normas , Transfusão de Componentes Sanguíneos/normas , Humanos , Estudos Prospectivos , Garantia da Qualidade dos Cuidados de Saúde , Taiwan
18.
Biotechnol Bioeng ; 73(3): 231-7, 2001 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-11257605

RESUMO

Including excess salt during lyophilization has been shown to increase the activity of freeze-dried subtilisin Carlsberg (SC) in anhydrous media by over 20,000-fold [Ru et al. (1999) Biotechnol Bioeng 63:233-241]. In the present study, salt-activated SC (KCl-SC) showed a 30% enhancement in enantioselectivity compared to the salt-free enzyme in a variety of organic solvents. Activity toward both enantiomers of N-acetyl-phenylalanine methyl ester (APME) increased in tandem by 2-3 orders of magnitude in all solvents, indicating that the mechanism of salt activation is inherent to the enzyme and does not strongly favor one enantiomer over the other. However, activity and enantioselectivity of salt-activated SC could be manipulated through changes in the lyophilization conditions. Variations in lyophilization time, initial KCl concentration, and initial lyophilization volume altered enantioselectivity over 2-fold. The changes in enantioselectivity reflected the activity for the L enantiomer, while the activity toward the D enantiomer was mostly unaffected. The results indicate that the lyophilization time and final water content of the KCl-SC are important determinants of enzyme activity for the L enantiomer, suggesting that the favored reaction is more sensitive to the structural integrity of the salt-activated enzyme.


Assuntos
Cloreto de Potássio/química , Subtilisina/química , Liofilização/métodos , Conformação Molecular , Solventes/química , Fatores de Tempo
19.
Proc Natl Acad Sci U S A ; 64(1): 345-51, 1969 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-4904642

RESUMO

The present studies indicate that T4 infection induces an alteration in host ribosomes which restricts the translation of host and other T4-unrelated template RNAs but permits normal translation of T4 RNA. A heat-labile factor has been isolated from T4-infected cell ribosomes which, when combined with normal cell ribosomes, confers upon the latter the property of selective T4 template RNA translation.


Assuntos
Colífagos , Código Genético , Ribossomos , Moldes Genéticos , Escherichia coli , Leucina/metabolismo , Fenilalanina/metabolismo , RNA Bacteriano , RNA Viral , Trítio
20.
Proc Natl Acad Sci U S A ; 67(2): 696-701, 1970 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-4943180

RESUMO

The phenomenon of selective translation of T4 template RNA by ribosomes from T4-infected cells, or factors derived therefrom, has been extended to studies on the initiation of protein synthesis. A high-salt extract derived from T4-infected ribosomes inhibits the formation of initiation complexes of MS2 and Escherichia coli template RNA with uninfected ribosomes while efficiently supporting the formation of initiation complexes with T4 template RNA. T4 factors also permit T5 template RNA to bind to E. coli ribosomes, which indicates that the T4 selective effect is not exclusive for T4 templates. Other evidence indicates that T4 factors do not alter the process of polypeptide chain elongation.


Assuntos
Colífagos/metabolismo , Biossíntese Peptídica , Ribossomos/metabolismo , Proteínas Virais/biossíntese , Cromatografia por Troca Iônica , Colífagos/análise , Escherichia coli/citologia , Formiatos/metabolismo , Metionina/metabolismo , Elongação Traducional da Cadeia Peptídica , Iniciação Traducional da Cadeia Peptídica , RNA de Transferência/metabolismo , Ribossomos/análise , Moldes Genéticos , Trítio
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