Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
1.
Sci Adv ; 2(3): e1501422, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-27034985

RESUMO

We tested the effectiveness of Faculty Institutes for Reforming Science Teaching IV (FIRST), a professional development program for postdoctoral scholars, by conducting a study of program alumni. Faculty professional development programs are critical components of efforts to improve teaching and learning in the STEM (Science, Technology, Engineering, and Mathematics) disciplines, but reliable evidence of the sustained impacts of these programs is lacking. We used a paired design in which we matched a FIRST alumnus employed in a tenure-track position with a non-FIRST faculty member at the same institution. The members of a pair taught courses that were of similar size and level. To determine whether teaching practices of FIRST participants were more learner-centered than those of non-FIRST faculty, we compared faculty perceptions of their teaching strategies, perceptions of environmental factors that influence teaching, and actual teaching practice. Non-FIRST and FIRST faculty reported similar perceptions of their teaching strategies and teaching environment. FIRST faculty reported using active learning and interactive engagement in lecture sessions more frequently compared with non-FIRST faculty. Ratings from external reviewers also documented that FIRST faculty taught class sessions that were learner-centered, contrasting with the teacher-centered class sessions of most non-FIRST faculty. Despite marked differences in teaching practice, FIRST and non-FIRST participants used assessments that targeted lower-level cognitive skills. Our study demonstrated the effectiveness of the FIRST program and the empirical utility of comparison groups, where groups are well matched and controlled for contextual variables (for example, departments), for evaluating the effectiveness of professional development for subsequent teaching practices.


Assuntos
Engenharia , Docentes , Matemática , Ciência , Desenvolvimento de Pessoal , Tecnologia , Feminino , Humanos , Masculino , Percepção , Avaliação de Programas e Projetos de Saúde , Ensino , Recursos Humanos
2.
CBE Life Sci Educ ; 14(2): 14:ar22, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26033870

RESUMO

The availability of reliable evidence for teaching practices after professional development is limited across science, technology, engineering, and mathematics disciplines, making the identification of professional development "best practices" and effective models for change difficult. We aimed to determine the extent to which postdoctoral fellows (i.e., future biology faculty) believed in and implemented evidence-based pedagogies after completion of a 2-yr professional development program, Faculty Institutes for Reforming Science Teaching (FIRST IV). Postdocs (PDs) attended a 2-yr training program during which they completed self-report assessments of their beliefs about teaching and gains in pedagogical knowledge and experience, and they provided copies of class assessments and video recordings of their teaching. The PDs reported greater use of learner-centered compared with teacher-centered strategies. These data were consistent with the results of expert reviews of teaching videos. The majority of PDs (86%) received video ratings that documented active engagement of students and implementation of learner-centered classrooms. Despite practice of higher-level cognition in class sessions, the items used by the PDs on their assessments of learning focused on lower-level cognitive skills. We attributed the high success of the FIRST IV program to our focus on inexperienced teachers, an iterative process of teaching practice and reflection, and development of and teaching a full course.


Assuntos
Escolha da Profissão , Docentes , Aprendizagem , Ensino , Cultura , Demografia , Feminino , Humanos , Masculino
3.
PeerJ ; 3: e901, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25945305

RESUMO

Consumer-mediated indirect effects at the community level are difficult to demonstrate empirically. Here, we show an explicit indirect effect of overfishing on competition between sponges and reef-building corals from surveys of 69 sites across the Caribbean. Leveraging the large-scale, long-term removal of sponge predators, we selected overfished sites where intensive methods, primarily fish-trapping, have been employed for decades or more, and compared them to sites in remote or marine protected areas (MPAs) with variable levels of enforcement. Sponge-eating fishes (angelfishes and parrotfishes) were counted at each site, and the benthos surveyed, with coral colonies scored for interaction with sponges. Overfished sites had >3 fold more overgrowth of corals by sponges, and mean coral contact with sponges was 25.6%, compared with 12.0% at less-fished sites. Greater contact with corals by sponges at overfished sites was mostly by sponge species palatable to sponge predators. Palatable species have faster rates of growth or reproduction than defended sponge species, which instead make metabolically expensive chemical defenses. These results validate the top-down conceptual model of sponge community ecology for Caribbean reefs, as well as provide an unambiguous justification for MPAs to protect threatened reef-building corals. An unanticipated outcome of the benthic survey component of this study was that overfished sites had lower mean macroalgal cover (23.1% vs. 38.1% for less-fished sites), a result that is contrary to prevailing assumptions about seaweed control by herbivorous fishes. Because we did not quantify herbivores for this study, we interpret this result with caution, but suggest that additional large-scale studies comparing intensively overfished and MPA sites are warranted to examine the relative impacts of herbivorous fishes and urchins on Caribbean reefs.

4.
J Allergy Clin Immunol ; 129(2): 456-63, 463.e1-3, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22206777

RESUMO

BACKGROUND: Eosinophilic esophagitis is a chronic allergic disease with insufficient treatment options. Results from animal studies suggest that IL-5 induces eosinophil trafficking in the esophagus. OBJECTIVE: We sought to evaluate the effect of reslizumab, a neutralizing antibody against IL-5, in children and adolescents with eosinophilic esophagitis. METHODS: Patients with symptom severity scores of moderate or worse and an esophageal biopsy specimen with 24 or more intraepithelial eosinophils per high-power field were randomly assigned to receive infusions of 1, 2, or 3 mg/kg reslizumab or placebo at weeks 0, 4, 8, and 12. The coprimary efficacy measures were changes in peak esophageal eosinophil count and the physician's global assessment score at week 15 (end of therapy). RESULTS: Two-hundred twenty-six patients received study medication. Median reductions from baseline to the end of therapy in peak esophageal eosinophil counts were 59%, 67%, 64%, and 24% in the 1, 2, and 3 mg/kg reslizumab (all P < .001) and placebo groups, respectively. All treatment groups, including the placebo group, showed improvements in physician's global assessment scores; the differences between the reslizumab and placebo groups were not statistically significant. The most common adverse events in the reslizumab groups were headache, cough, nasal congestion, and upper respiratory tract infection. One patient in each reslizumab group and 2 in the placebo group had serious adverse events; none were considered related to the study medication. CONCLUSION: Reslizumab significantly reduced intraepithelial esophageal eosinophil counts in children and adolescents with eosinophilic esophagitis. However, improvements in symptoms were observed in all treatment groups and were not associated with changes in esophageal eosinophil counts.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Esofagite Eosinofílica/tratamento farmacológico , Adolescente , Criança , Pré-Escolar , Método Duplo-Cego , Esofagite Eosinofílica/imunologia , Eosinófilos/efeitos dos fármacos , Eosinófilos/imunologia , Feminino , Humanos , Contagem de Leucócitos , Masculino , Qualidade de Vida , Resultado do Tratamento
5.
Science ; 333(6047): 1220-1; author reply 1221, 2011 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-21885755
6.
Am J Respir Crit Care Med ; 184(10): 1125-32, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21852542

RESUMO

RATIONALE: Eosinophilic asthma is a phenotype of asthma characterized by the persistence of eosinophils in the airways. IL-5 is involved in the activation and survival of eosinophils. OBJECTIVES: To evaluate the effect of the antibody to IL-5, reslizumab, in patients with eosinophilic asthma that is poorly controlled with high-dose inhaled corticosteroid. METHODS: Patients were randomly assigned to receive infusions of reslizumab at 3.0 mg/kg (n = 53) or placebo (n = 53) at baseline and at Weeks 4, 8, and 12, with stratification by baseline Asthma Control Questionnaire (ACQ) score less than or equal to 2 or greater than 2. The primary efficacy measure was the difference between the reslizumab and placebo groups in the change in ACQ score from baseline to end of therapy (Week 15 or early withdrawal). MEASUREMENTS AND MAIN RESULTS: Mean changes from baseline to end of therapy in ACQ score were -0.7 in the reslizumab group and -0.3 in the placebo group (P = 0.054) and in FEV(1) were 0.18 and -0.08 L, respectively (P = 0.002). In those patients with nasal polyps, the changes in ACQ score were -1.0 and -0.1, respectively (P = 0.012). Median percentage reductions from baseline in sputum eosinophils were 95.4 and 38.7%, respectively (P = 0.007). Eight percent of patients in the reslizumab group and 19% of patients in the placebo group had an asthma exacerbation (P = 0.083). The most common adverse events with reslizumab were nasopharyngitis, fatigue, and pharyngolaryngeal pain. CONCLUSIONS: Patients receiving reslizumab showed significantly greater reductions in sputum eosinophils, improvements in airway function, and a trend toward greater asthma control than those receiving placebo. Reslizumab was generally well tolerated.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Asma/tratamento farmacológico , Interleucina-5/antagonistas & inibidores , Eosinofilia Pulmonar/tratamento farmacológico , Adulto , Asma/fisiopatologia , Método Duplo-Cego , Eosinófilos/efeitos dos fármacos , Feminino , Volume Expiratório Forçado/efeitos dos fármacos , Humanos , Interleucina-5/fisiologia , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Escarro/citologia , Inquéritos e Questionários , Resultado do Tratamento
7.
Ecology ; 91(2): 560-70, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20392020

RESUMO

The structure of Caribbean coral reef communities has been altered by numerous anthropogenic and natural stressors. Demographic studies of key functional groups have furthered efforts to describe and understand these changes. Little is known, however, about the demographics of sponges on coral reefs, despite their abundance and the important functions they perform (e.g., increased habitat complexity, water filtration). We have monitored permanent plots on reefs off Key Largo, Florida, USA, to study the demography of a particularly important species, the giant barrel sponge, Xestospongia muta. From 2000 to 2006, population densities of X. muta significantly increased at sites on Conch Reef by a mean of 46% (range = 16-108%) and on Pickles Reef by a mean of 33%. In 2006, densities of X. muta on Conch Reef ranged from 0.134 to 0.277 sponges/m2, and mean sponge volume was 1488 cm3/m2, with the largest size class of sponges constituting 75% of the total volume. Increased population density resulted from a significant increase in the number of sponges in the smallest size class. Recruit survival did not significantly change through time; however, a significant interaction between season and year on recruitment suggests that large recruitment pulses are driving population increases. Mean yearly recruitment rates ranged from 0.011 to 0.025 recruits x m(-2) x yr(-1), with pulses as high as 0.036 recruits/m2. To explore the demographic processes behind the population increase and determine future population growth of X. muta under present reef conditions, a stage-based matrix modeling approach was used. Variable recruitment pulses and mortality events were hypothesized to be large determinants of the demographic patterns observed for X. muta. Elasticity and life table response analysis revealed that survival of individuals in the largest size class has the greatest effect on population growth. Projections indicate that populations of X. muta will continue to increase under present conditions; however population growth may be negatively affected by continued mortality of the largest individuals from a recently described pathogenic syndrome.


Assuntos
Poríferos/fisiologia , Animais , Ecossistema , Florida , Oceanos e Mares , Crescimento Demográfico , Fatores de Tempo
8.
J Clin Pharmacol ; 47(3): 305-14, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17322142

RESUMO

The safety and pharmacokinetics of anidulafungin coadministered with tacrolimus were investigated using a single-sequence, open-label design. Healthy volunteers received 5 mg tacrolimus orally on days 1 and 13 of the study. Anidulafungin (200 mg) was administered intravenously on day 4, followed by 100-mg doses on days 5 through 13. Key pharmacokinetic parameters, including C(max), AUC, t((1/2)), CL, and V(ss), were derived from concentration-time data. The 90% confidence intervals (CIs) of the ratios of mean pharmacokinetic parameters of anidulafungin plus tacrolimus to each drug alone were well within the 80% to 125% bioequivalence range, indicating no pharmacokinetic interaction. This ratio was 101.6 (90% CI: 92.77-111.22) for tacrolimus AUC(0-infinity) and 107.2 (90% CI: 105.1-109.4) for anidulafungin AUC(ss). The 2 drugs were well tolerated, and no drug-related serious adverse events were reported. Because of its lack of pharmacokinetic interaction with key immunosuppressive agents, anidulafungin is an important option for the prevention and treatment of invasive fungal infections in transplant recipients.


Assuntos
Peptídeos Cíclicos/farmacocinética , Tacrolimo/farmacocinética , Administração Oral , Adolescente , Adulto , Alanina Transaminase/sangue , Anidulafungina , Antifúngicos/administração & dosagem , Antifúngicos/efeitos adversos , Antifúngicos/farmacocinética , Área Sob a Curva , Aspartato Aminotransferases/sangue , Creatina Quinase/sangue , Tontura/induzido quimicamente , Interações Medicamentosas , Equinocandinas , Fadiga/induzido quimicamente , Meia-Vida , Cefaleia/induzido quimicamente , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/efeitos adversos , Imunossupressores/farmacocinética , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Noctúria/induzido quimicamente , Peptídeos Cíclicos/administração & dosagem , Peptídeos Cíclicos/efeitos adversos , Tacrolimo/administração & dosagem , Tacrolimo/efeitos adversos , Equivalência Terapêutica , Tromboflebite/induzido quimicamente
9.
J Antimicrob Chemother ; 55 Suppl 2: ii25-30, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15750034

RESUMO

The selection of a novel weekly dalbavancin dosage regimen was based on pharmacokinetic and pharmacodynamic data from humans and an animal model of infection. The results from the granuloma pouch model of infection suggested that dalbavancin concentrations >/=5 mg/L are necessary for extended in vivo activity. Serum bactericidal activity assessments demonstrated that dalbavancin serum concentrations of approximately 20 mg/L were bactericidal upon two-fold dilution. These data, coupled with simulations based on the pharmacokinetic profile derived from a clinical study in healthy volunteers, were used to design the weekly regimen studied in the initial efficacy trial. This efficacy study showed that a two-dose weekly regimen was well tolerated and associated with a higher clinical response rate than the comparator regimens. The data collectively support the further study of dalbavancin as a once-weekly regimen for the treatment of infections caused by Gram-positive bacteria.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Glicopeptídeos/administração & dosagem , Glicopeptídeos/farmacocinética , Animais , Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Esquema de Medicação , Glicopeptídeos/uso terapêutico , Humanos , Teicoplanina/análogos & derivados
10.
J Clin Pharmacol ; 45(2): 227-33, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15647416

RESUMO

Anidulafungin is a novel antifungal agent of the echinocandin class that is intended for the treatment of invasive fungal disease. It is likely that anidulafungin will be coadministered with cyclosporine. In vitro studies and clinical studies were performed to evaluate the effect of anidulafungin on cyclosporine metabolism and to investigate the safety and pharmacokinetics of anidulafungin when concomitantly administered with cyclosporine. The potential for anidulafungin to inhibit the metabolism of cyclosporine was evaluated by pooled human hepatic microsomal protein fractions in vitro, incubating 3H-cyclosporine with different concentrations of anidulafungin. The safety of coadministration and the effects of cyclosporine on the pharmacokinetics of anidulafungin were assessed in a multiple-dose, open-label clinical study of 12 healthy volunteers. Subjects received a 200-mg intravenous loading dose of anidulafungin, followed by a daily 100-mg intravenous maintenance dose on days 2 through 8. An oral solution of cyclosporine (Neoral oral solution; 100 mg/mL) 1.25 mg/kg was also administered to subjects twice daily on days 5 through 8. In the in vitro study, the addition of anidulafungin had no effect on cyclosporine metabolism by human hepatic microsomal protein fractions. In the clinical study, no dose-limiting toxicities or serious adverse events occurred. A small increase in anidulafungin concentrations and drug exposure (22%) was observed after 4 days of dosing with cyclosporine and was not considered to be clinically relevant. The results support the concomitant use of anidulafungin and cyclosporine without the need for dosage adjustments of either drug.


Assuntos
Ciclosporina/administração & dosagem , Ciclosporina/farmacocinética , Peptídeos Cíclicos/administração & dosagem , Peptídeos Cíclicos/farmacocinética , Administração Oral , Anidulafungina , Antifúngicos/sangue , Antifúngicos/química , Antifúngicos/farmacologia , Área Sob a Curva , Disponibilidade Biológica , Ciclosporina/sangue , Esquema de Medicação , Quimioterapia Combinada , Equinocandinas , Feminino , Humanos , Injeções Intravenosas , Masculino , Taxa de Depuração Metabólica , Testes de Sensibilidade Microbiana/métodos , Microssomos Hepáticos/química , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Peptídeos Cíclicos/sangue , Fatores de Tempo , Trítio
11.
Clin Infect Dis ; 39(6): 770-5, 2004 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-15472806

RESUMO

Anidulafungin is a novel antifungal agent of the echinocandin class. This randomized, double-blind, double-dummy study compared the efficacy and safety of intravenous anidulafungin to that of oral fluconazole in 601 patients with endoscopically and microbiologically documented esophageal candidiasis. Patients received intravenous anidulafungin (100 mg on day 1, followed by 50 mg per day) or oral fluconazole (200 mg on day 1, followed by 100 mg per day) for 7 days beyond resolution of symptoms (range, 14-21 days). At the end of therapy, the rate of endoscopic success for anidulafungin (242 [97.2%] of 249 treated patients) was found to be statistically noninferior to that for fluconazole (252 [98.8%] of 255 treated patients; treatment difference, -1.6%; 95% confidence interval, -4.1 to 0.8). The safety profile of anidulafungin was similar to that of fluconazole; treatment-related adverse events occurred in 9.3% and 12.0% of patients, respectively. Laboratory parameters were similar between treatment arms. Anidulafungin is as safe and effective as oral fluconazole for the treatment of esophageal candidiasis, when assessed at the completion of therapy.


Assuntos
Antifúngicos/uso terapêutico , Candidíase/tratamento farmacológico , Doenças do Esôfago/microbiologia , Fluconazol/uso terapêutico , Peptídeos Cíclicos/uso terapêutico , Administração Oral , Adulto , Idoso , Anidulafungina , Antifúngicos/administração & dosagem , Método Duplo-Cego , Equinocandinas , Doenças do Esôfago/tratamento farmacológico , Feminino , Fluconazol/administração & dosagem , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Peptídeos Cíclicos/administração & dosagem
12.
Antimicrob Agents Chemother ; 48(6): 2021-4, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15155194

RESUMO

This study evaluated the safety and efficacy of anidulafungin, a novel echinocandin, in patients with invasive candidiasis, including candidemia. A total of 123 eligible patients were randomized to one of three intravenous regimens, 50, 75, or 100 mg once daily. Treatment continued for 2 weeks beyond resolution or improvement of signs and symptoms. The primary efficacy criterion was a successful global response rate (i.e., clinical and microbiological success) in the evaluable population at the follow-up (FU) visit, 2 weeks after end of therapy (EOT). One hundred twenty (120) patients received at least one dose of anidulafungin; 68 were evaluable. Review of adverse events and laboratory data indicated no dose response for safety parameters. Non-albicans Candida species accounted for approximately one-half of all isolates. Success rates at EOT were 84, 90, and 89% in the 50-, 75-, and 100-mg groups, respectively. At FU, the success rates were 72, 85, and 83%. Phase 3 studies of anidulafungin for the treatment of invasive candidiasis and candidemia are warranted.


Assuntos
Antifúngicos/uso terapêutico , Candidíase/tratamento farmacológico , Fungemia/tratamento farmacológico , Peptídeos Cíclicos/uso terapêutico , APACHE , Adulto , Idoso , Idoso de 80 Anos ou mais , Anidulafungina , Antifúngicos/administração & dosagem , Antifúngicos/efeitos adversos , Candidíase/microbiologia , Relação Dose-Resposta a Droga , Equinocandinas , Feminino , Fungemia/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeos Cíclicos/administração & dosagem , Peptídeos Cíclicos/efeitos adversos , Estudos Prospectivos
13.
Oecologia ; 131(1): 125-136, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28547502

RESUMO

Despite their high nutritional value and a lack of physical defenses, most marine sponges appear to be minimally affected by predators, competitors, and fouling organisms, possibly due to sponge chemical defenses. In the last 15 years, several triterpene glycosides have been isolated from sponges, but their ecological or physiological roles are largely unknown. We tested triterpene glycosides from Erylus formosus and Ectyoplasia ferox, Caribbean sponges belonging to two different orders, in field and laboratory assays for effects on fish feeding, attachment by potential biofilm-forming bacteria, fouling by invertebrates and algae, and overgrowth by neighboring sponges. Formoside and other triterpene glycosides from Erylus formosus deterred predation, microbial attachment, and fouling by invertebrates and algae. Triterpene glycosides from Ectyoplasia ferox were found to be antipredatory and allelopathic. Thus, triterpene glycosides in these sponges appear to have multiple ecological functions. Tests with different triterpene glycosides at several concentrations indicated that small differences in molecular structure affect ecological activity. In order to establish whether triterpene glycosides could be involved in water-borne versus surface-mediated interactions, the presence of triterpene glycosides in the seawater surrounding live sponges was measured using two in situ sampling methods followed by HPLC and NMR spectral analysis. Water-borne triterpene glycosides were below detection limits for both species. However, top sponge layers and swabs of the surfaces of both sponges contained sufficiently high concentrations of triterpene glycosides to deter bacterial settlement and fouling of Erylus formosus surfaces and overgrowth of Ectyoplasia ferox by neighboring sponges. Enemies of these sponges appear to be deterred by surface contact of triterpene glycosides rather than by water-borne interactions. The dual strategy of employing one group of compounds for multiple purposes and minimizing the loss of compounds into seawater suggests that these organisms utilize chemical defenses with efficiency.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA