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1.
Nurse Educ Pract ; 76: 103929, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38461591

RESUMEN

AIM: The aim of this study was to undertake an in-depth exploration of the lived experiences of in-hospital, non-intensive care, ward-based nurses' experiences of real-life CPR events. BACKGROUND: There is growing evidence suggesting that may nurses not be able to successfully perform in a cardiac arrest situation. Reasons include a lack of clear leadership at the arrest, performance anxiety, role confusion and knowledge and skill degradation over time. METHODS: In-depth semi-structured interviews were conducted with fifteen ward-based hospital nurses from three hospitals. Interviews were recorded, transcribed verbatim and inductive thematic analysis was completed using NVivo 12 software. FINDINGS: Four main themes emerged from data. The main themes are: (1) Not Being able to Perform When it Matters, (2) Working Really Well as a Team, (3) Reflecting on the Experience: The Good, the Bad & the Ugly and (4) Learning to get it Right for Next Time CONCLUSION: Performing BLS is a stressful and anxiety-provoking experience for ward-based nurses. Anxiety levels appear to decrease slightly only when nurses have had at least one previous real-life experience with resuscitation. Current BLS education does not prepare nurses for the complexities of resuscitation. Future BLS education should focus on in-depth scenarios, including interdisciplinary team training and with greater frequency than the current yearly mandatory sessions. Listening to the lived experiences of nurses who have performed BLS has given much needed insight into approaches that educators can use to improve BLS education delivery.


Asunto(s)
Reanimación Cardiopulmonar , Enfermeras y Enfermeros , Humanos , Reanimación Cardiopulmonar/educación , Competencia Clínica , Aprendizaje , Hospitales
2.
Open Forum Infect Dis ; 8(11): ofab464, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34805425

RESUMEN

BACKGROUND: We aimed to evaluate a testing program to facilitate control of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission at a large university and measure spread in the university community using viral genome sequencing. METHODS: Our prospective longitudinal study used remote contactless enrollment, daily mobile symptom and exposure tracking, and self-swab sample collection. Individuals were tested if the participant was exposed to a known SARS-CoV-2-infected person, developed new symptoms, or reported high-risk behavior (such as attending an indoor gathering without masking or social distancing), if a member of a group experiencing an outbreak, or at enrollment. Study participants included students, staff, and faculty at an urban public university during the Autumn quarter of 2020. RESULTS: We enrolled 16 476 individuals, performed 29 783 SARS-CoV-2 tests, and detected 236 infections. Seventy-five percent of positive cases reported at least 1 of the following: symptoms (60.8%), exposure (34.7%), or high-risk behaviors (21.5%). Greek community affiliation was the strongest risk factor for testing positive, and molecular epidemiology results suggest that specific large gatherings were responsible for several outbreaks. CONCLUSIONS: A testing program focused on individuals with symptoms and unvaccinated persons who participate in large campus gatherings may be effective as part of a comprehensive university-wide mitigation strategy to control the spread of SARS-CoV-2.

4.
mBio ; 10(3)2019 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-31138748

RESUMEN

Cryptococcus neoformans is an encapsulated yeast responsible for approximately a quarter of a million deaths worldwide annually despite therapy, and upwards of 11% of HIV/AIDS-related deaths, rivaling the impact of tuberculosis and malaria. However, the most effective antifungal agent, amphotericin B, requires intravenous delivery and has significant renal and hematopoietic toxicity, making it difficult to utilize, especially in resource-limited settings. The present studies describe a new nanoparticle crystal encapsulated formulation of amphotericin B known as encochleated amphotericin B (CAmB) that seeks to provide an oral formulation that is low in toxicity and cost. Using a 3-day delayed model of murine cryptococcal meningoencephalitis and a large inoculum of a highly virulent strain of serotype A C. neoformans, CAmB, in combination with flucytosine, was found to have efficacy equivalent to parental amphotericin B deoxycholate with flucytosine and superior to oral fluconazole without untoward toxicity. Transport of fluorescent CAmB particles to brain as well as significant brain levels of amphotericin drug was demonstrated in treated mice, and immunological profiles were similar to those of mice treated with conventional amphotericin B. Additional toxicity studies using a standardized rat model showed negligible toxicity after a 28-day treatment schedule. These studies thus offer the potential for an efficacious oral formulation of a known fungicidal drug against intrathecal cryptococcal disease.IMPORTANCECryptococcus neoformans is a significant global fungal pathogen that kills an estimated quarter of a million HIV-infected individuals yearly and has poor outcomes despite therapy. The most effective therapy, amphotericin B, is highly effective in killing the fungus but is available only in highly toxic, intravenous formulations that are unavailable in most of the developing world, where cryptococcal disease in most prevalent. For example, in Ethiopia, reliance on the orally available antifungal fluconazole results in high mortality, even when initiated as preemptive therapy at the time of HIV diagnosis. Thus, alternative agents could result in significant saving of lives. Toward this end, the present work describes the development of a new formulation of amphotericin B (CAmB) that encapsulates the drug as a crystal lipid nanoparticle that facilitates oral absorption and prevents toxicity. Successful oral absorption of the drug was demonstrated in a mouse model that, in combination with the antifungal flucytosine, provided efficacy equal to a parental preparation of amphotericin B plus flucytosine. These studies demonstrate the potential for CAmB in combination with flucytosine to provide an effective oral formulation of a well-known, potent fungicidal drug combination.


Asunto(s)
Anfotericina B/uso terapéutico , Antifúngicos/uso terapéutico , Criptococosis/tratamiento farmacológico , Meningoencefalitis/tratamiento farmacológico , Administración Oral , Anfotericina B/química , Animales , Antifúngicos/química , Cryptococcus neoformans/efectos de los fármacos , Ácido Desoxicólico/uso terapéutico , Modelos Animales de Enfermedad , Combinación de Medicamentos , Composición de Medicamentos , Quimioterapia Combinada , Femenino , Flucitosina/uso terapéutico , Lípidos/química , Masculino , Meningoencefalitis/microbiología , Ratones , Nanopartículas/química , Ratas , Ratas Sprague-Dawley
5.
Dis Esophagus ; 32(3)2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30124795

RESUMEN

Acid exposure time commonly varies from day-to-day in prolonged wireless pH monitoring. Thus, diagnosis based on the number of days with abnormal acid burden may be misleading or inconclusive. We hypothesize that assessing longitudinal patterns of acid exposure may be diagnostically useful. Therefore, this study aims to describe acid exposure trajectories and evaluate agreement between identified trajectory patterns and conventional grouping. In this retrospective cohort study, we assessed patients with nonresponse to proton pump inhibitor therapy who underwent wireless pH monitoring (≥72 h) off therapy between August 2010 and September 2016. The primary outcome was esophageal acid exposure time. Subjects were grouped as 0, 1, 2, and 3+ days positive based on number of days with an acid exposure time >5.0%. Latent class group-based mixture model identified distinct longitudinal acid exposure trajectory groups. Of 212 subjects included 44%, 18%, 14%, and 24% had 0, 1, 2, 3+ days positive, respectively. Group-based modeling identified three significantly stable acid exposure trajectories: low (64%), middle (28%), and high (8%). Trajectory grouping and days positive grouping agreed substantially (weighted K 0.69; 95% CI: 0.63-0.76). Trajectory grouping identified 62% of subjects with conventionally inconclusive studies (one or two days positive) into the low trajectory. Agreement between trajectory groups when using three versus four days of monitoring was substantial (K 0.70; CI: 0.61-0.78). In summary, we found that patients with nonresponse to proton pump inhibitors follow three acid exposure trajectories over prolonged pH-monitoring periods: low, middle, and high. Compared to conventional day positive grouping, the trajectory modeling identified the majority of inconclusive days positive into the low trajectory group. Analyzing prolonged wireless pH data according to trajectories may be a complimentary method to conventional grouping, and may increase precision and accuracy in identifying acid burden.


Asunto(s)
Monitorización del pH Esofágico/estadística & datos numéricos , Reflujo Gastroesofágico/diagnóstico , Factores de Tiempo , Monitorización del pH Esofágico/métodos , Esófago/química , Femenino , Reflujo Gastroesofágico/tratamiento farmacológico , Humanos , Concentración de Iones de Hidrógeno , Análisis de Clases Latentes , Estudios Longitudinales , Masculino , Inhibidores de la Bomba de Protones/uso terapéutico , Reproducibilidad de los Resultados , Estudios Retrospectivos
6.
Neurogastroenterol Motil ; 30(6): e13287, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29315993

RESUMEN

BACKGROUND: Achalasia is a disease of mechanical esophageal dysfunction characterized by dysphagia, chest pain, regurgitation, and malnutrition. The Eckardt symptom score (ESS) is the gold standard self-report assessment tool. Current guidelines outline a three-step approach to patient reported outcomes measure design. Developed prior to these policies, the ESS has not undergone rigorous testing of its reliability and validity. METHODS: Adult achalasia patients retrospectively identified via a patient registry were grouped based on treatment history. Patients were grouped PREPOST (completed ESS, GERDQ, brief esophageal dysphagia questionnaire, NIH PROMIS Global Health, high resolution manometry, timed barium esophagram prior to treatment and after) and POST (completed measures only after treatment). Clinical characteristics, treatment type and date were obtained via medical record. Standardized psychometric analyses for reliability and construct validity were performed. KEY RESULTS: 107 patients identified; 83 POST and 24 PREPOST. The ESS has fair internal consistency and split-half reliability with a single factor structure. Dysphagia accounts for half the variance in ESS, while chest pain and weight loss account for 10% each. Pre-post-surgical assessment demonstrates improvements in ESS, except for weight loss. Effect sizes range from 0.24 to 2.53, with greatest change in regurgitation. Validity of the ESS is supported by modest correlations with GERDQ, HRQOL, and physiological data. CONCLUSIONS & INFERENCES: The ESS demonstrates fair reliability and validity, with a single factor structure mostly explained by dysphagia. Based on psychometric findings, weight loss and chest pain items may be decreasing ESS reliability and validity. Further assessment of the ESS under FDA guidelines is warranted.


Asunto(s)
Acalasia del Esófago/diagnóstico , Acalasia del Esófago/fisiopatología , Encuestas Epidemiológicas/normas , Manometría/normas , Índice de Severidad de la Enfermedad , Adulto , Anciano , Estudios Transversales , Femenino , Encuestas Epidemiológicas/métodos , Humanos , Masculino , Manometría/métodos , Persona de Mediana Edad , Sistema de Registros/normas , Reproducibilidad de los Resultados , Estudios Retrospectivos , Pérdida de Peso/fisiología
7.
Artículo en Inglés | MEDLINE | ID: mdl-29098750

RESUMEN

BACKGROUND: Increased esophagogastric junction (EGJ) distensibility is thought to contribute to gastroesophageal reflux disease (GERD). Using the functional lumen imaging probe (FLIP), we aimed to assess the esophageal response to distension among patients undergoing esophageal pH monitoring. METHODS: 25 patients (ages 22-73; 13 females) who underwent ambulatory wireless esophageal pH testing while off proton-pump inhibitors were evaluated with FLIP during sedated upper endoscopy. Esophageal reflux was quantified by total percent acid exposure time (AET; <6% was considered normal). FLIP studies were analyzed using a customized program generate FLIP topography plots to identify esophageal contractility patterns and to calculate the EGJ-distensibility index (DI). Reflux symptoms were assessed with the GERDQ. Values reflect median (interquartile range). RESULTS: Among all patients, the AET was 7.2% (3.7-11.1) and EGJ-DI was 4.2 (2.5-7.6) mm2 /mm Hg. Repetitive antegrade contractions (RACs) were induced in 19/25 (76%) of patients; AET was lower among patients with (6.1%, 3-7.8) than without (14.9, 8.5-22.3) RACs (P = .009). Correlation was weak and insignificant between AET and EGJ-DI, GERDQ and AET, and GERDQ and EGJ-DI. Patients with abnormal AET (n = 16) and normal AET (n = 9) had similar EGJ-DI, 4.6 mm2 /mm Hg (2.9-9.2) vs 3.2 (2.2-5.1), P = .207 and GERDQ, P = .138. CONCLUSIONS: Abnormal esophageal acid exposure was associated with an impaired contractile response to volume distention of the esophagus. This supports that acid exposure is dependent on acid clearance mechanisms.


Asunto(s)
Trastornos de la Motilidad Esofágica/fisiopatología , Unión Esofagogástrica/fisiopatología , Reflujo Gastroesofágico/fisiopatología , Adulto , Anciano , Trastornos de la Motilidad Esofágica/complicaciones , Monitorización del pH Esofágico , Femenino , Reflujo Gastroesofágico/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Contracción Muscular , Adulto Joven
8.
Astrobiology ; 13(12): 1166-98, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24303959

RESUMEN

The future exploration of Mars will require access to the subsurface, along with acquisition of samples for scientific analysis and ground-truthing of water ice and mineral reserves for in situ resource utilization. The Icebreaker drill is an integral part of the Icebreaker mission concept to search for life in ice-rich regions on Mars. Since the mission targets Mars Special Regions as defined by the Committee on Space Research (COSPAR), the drill has to meet the appropriate cleanliness standards as requested by NASA's Planetary Protection Office. In addition, the Icebreaker mission carries life-detection instruments; and in turn, the drill and sample delivery system have to meet stringent contamination requirements to prevent false positives. This paper reports on the development and testing of the Icebreaker drill, a 1 m class rotary-percussive drill and triple redundant sample delivery system. The drill acquires subsurface samples in short, approximately 10 cm bites, which makes the sampling system robust and prevents thawing and phase changes in the target materials. Autonomous drilling, sample acquisition, and sample transfer have been successfully demonstrated in Mars analog environments in the Arctic and the Antarctic Dry Valleys, as well as in a Mars environmental chamber. In all environments, the drill has been shown to perform at the "1-1-100-100" level; that is, it drilled to 1 m depth in approximately 1 hour with less than 100 N weight on bit and approximately 100 W of power. The drilled substrate varied and included pure ice, ice-rich regolith with and without rocks and with and without 2% perchlorate, and whole rocks. The drill is currently at a Technology Readiness Level (TRL) of 5. The next-generation Icebreaker drill weighs 10 kg, which is representative of the flightlike model at TRL 5/6.


Asunto(s)
Hielo , Marte , Vuelo Espacial
9.
Mar Pollut Bull ; 71(1-2): 230-9, 2013 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-23623663

RESUMEN

Transcriptional profiling can elucidate adaptive/toxicity pathways participating in achieving homeostasis or leading to pathogenesis in marine biota exposed to chemical substances. With the aim of analyzing transcriptional responses in the mussel Mytilus edulis exposed to the corrosive and putatively carcinogenic hydrocarbon styrene (3-5 ppm, 3days), a forward subtracted (SSH) cDNA library was produced. Female mussels were selected and digestive gland mRNA was isolated. A library with 1440 clones was produced and a total of 287 clones were sequenced, 53% being identified through BlastN analysis against Mytibase and DeepSeaVent databases. Those genes included GO terms such as 'response to drugs', 'immune defense' and 'cell proliferation'. Furthermore, sequences related to chitin and beta-1-3-glucan metabolism were also up-regulated by styrene. Many of the obtained sequences could not be annotated constituting new mussel sequences. In conclusion, this SSH study reveals novel sequences useful to generate molecular biomarkers of styrene exposure in mussels.


Asunto(s)
Monitoreo del Ambiente/métodos , Biblioteca de Genes , Mytilus edulis/fisiología , Estireno/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Biomarcadores/metabolismo , Femenino , Expresión Génica/efectos de los fármacos , Perfilación de la Expresión Génica
10.
Antimicrob Agents Chemother ; 57(6): 2526-34, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23507282

RESUMEN

Solithromycin, a new macrolide, and the first fluoroketolide in clinical development, with activity against macrolide-resistant bacteria, was tested in 132 patients with moderate to moderately severe community-acquired bacterial pneumonia (CABP) in a multicenter, double-blind, randomized phase 2 study. Patients were enrolled and randomized (1:1) to either 800 mg solithromycin orally (PO) on day 1, followed by 400 mg PO daily on days 2 to 5, or 750 mg levofloxacin PO daily on days 1 to 5. Efficacy outcome rates of clinical success at the test-of-cure visit 4 to 11 days after the last dose of study drug were comparable in the intent-to-treat (ITT) (84.6% for solithromycin versus 86.6% for levofloxacin) and microbiological-intent-to-treat (micro-ITT) (77.8% for solithromycin versus 71.4% for levofloxacin) populations. Early response success rates at day 3, defined as improvement in at least two cardinal symptoms of pneumonia, were also comparable (72.3% for solithromycin versus 71.6% for levofloxacin). More patients treated with levofloxacin than with solithromycin experienced treatment-emergent adverse events (TEAEs) during the study (45.6% versus 29.7%). The majority of TEAEs were mild or moderate gastrointestinal symptoms and included nausea (1.6% for solithromycin; 10.3% for levofloxacin), diarrhea (7.8% for solithromycin; 5.9% for levofloxacin), and vomiting (0% for solithromycin; 4.4% for levofloxacin). Six patients, all of whom received levofloxacin, discontinued the study drug due to an adverse event. Solithromycin demonstrated comparable efficacy and favorable safety relative to levofloxacin. These findings support a phase 3 study of solithromycin for the treatment of CABP. (This study has been registered at ClinicalTrials.gov under registration no. NCT01168713.).


Asunto(s)
Infecciones Comunitarias Adquiridas/tratamiento farmacológico , Levofloxacino , Macrólidos/efectos adversos , Macrólidos/uso terapéutico , Ofloxacino/efectos adversos , Ofloxacino/uso terapéutico , Neumonía Bacteriana/tratamiento farmacológico , Triazoles/efectos adversos , Triazoles/uso terapéutico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Infecciones Comunitarias Adquiridas/microbiología , Método Doble Ciego , Femenino , Humanos , Macrólidos/administración & dosificación , Masculino , Persona de Mediana Edad , Ofloxacino/administración & dosificación , Neumonía Bacteriana/microbiología , Resultado del Tratamiento , Triazoles/administración & dosificación , Adulto Joven
11.
Br J Clin Pharmacol ; 75(2): 524-37, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22759078

RESUMEN

AIMS: To assess the safety and pharmacokinetics of a new synthetic ozonide antimalarial, OZ439, in a first-in-man, double-blind study in healthy volunteers. METHODS: OZ439 was administered as single oral daily doses of a capsule formulation (50-1200 mg) or an oral dispersion (400-1600 mg, fed and fasted states) and for up to 3 days as an oral dispersion (200-800 mg day(-1)). Plasma concentrations of OZ439 and its metabolites were measured by LC-MS. RESULTS: The pharmacokinetic (PK) profile of OZ439 was characterized by a t(max) of around 3 h, followed by a multiphasic profile with a terminal half-life of 25-30 h. The PK parameters were approximately dose proportional for each group and profiles of the metabolites followed a similar pattern to that of the parent compound. Following dosing for 3 days, accumulation was less than two-fold but steady-state was not achieved. In the presence of food, no effect was observed on the t(1/2) of OZ439 while the exposure was increased by 3 to 4.5-fold. Exposure was higher and inter-subject variability was reduced when OZ439 was administered as an oral dispersion compared with a capsule. The urinary clearance of OZ439 and its metabolites was found to be negligible and OZ439 did not induce CYP3A4. The antimalarial activity profiles of a subset of serum samples suggested that the major antimalarial activity originated from OZ439 rather than from any of the metabolites. CONCLUSION: The safety and pharmacokinetic profile of OZ439 merits progression to phase 2a proof of concept studies in the target population of acute uncomplicated malaria.


Asunto(s)
Adamantano/análogos & derivados , Antimaláricos/efectos adversos , Antimaláricos/farmacocinética , Peróxidos/efectos adversos , Peróxidos/farmacocinética , Adamantano/efectos adversos , Adamantano/farmacocinética , Administración Oral , Adolescente , Adulto , Área Bajo la Curva , Cromatografía Liquida , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Ayuno , Femenino , Interacciones Alimento-Droga , Semivida , Humanos , Masculino , Espectrometría de Masas , Persona de Mediana Edad , Adulto Joven
12.
Malar J ; 11: 270, 2012 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-22877082

RESUMEN

Pyronaridine was synthesized in 1970 at the Institute of Chinese Parasitic Disease and has been used in China for over 30 years for the treatment of malaria. Pyronaridine has high potency against Plasmodium falciparum, including chloroquine-resistant strains. Studies in various animal models have shown pyronaridine to be effective against strains resistant to other anti-malarials, including chloroquine. Resistance to pyronaridine appears to emerge slowly and is further retarded when pyronaridine is used in combination with other anti-malarials, in particular, artesunate. Pyronaridine toxicity is generally less than that of chloroquine, though evidence of embryotoxicity in rodents suggests use with caution in pregnancy. Clinical pharmacokinetic data for pyronaridine indicates an elimination T1/2 of 13.2 and 9.6 days, respectively, in adults and children with acute uncomplicated falciparum and vivax malaria in artemisinin-combination therapy. Clinical data for mono or combined pyronaridine therapy show excellent anti-malarial effects against P. falciparum and studies of combination therapy also show promise against Plasmodium vivax. Pyronaridine has been developed as a fixed dose combination therapy, in a 3:1 ratio, with artesunate for the treatment of acute uncomplicated P. falciparum malaria and blood stage P. vivax malaria with the name of Pyramax® and has received Positive Opinion by European Medicines Agency under the Article 58 procedure.


Asunto(s)
Antimaláricos/efectos adversos , Antimaláricos/uso terapéutico , Malaria Falciparum/tratamiento farmacológico , Malaria Vivax/tratamiento farmacológico , Naftiridinas/efectos adversos , Naftiridinas/uso terapéutico , Antimaláricos/farmacocinética , Antimaláricos/farmacología , China , Quimioterapia Combinada/métodos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Humanos , Naftiridinas/farmacocinética , Naftiridinas/farmacología , Plasmodium falciparum/efectos de los fármacos , Plasmodium vivax/efectos de los fármacos , Resultado del Tratamiento
13.
Antimicrob Agents Chemother ; 56(2): 703-7, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22083475

RESUMEN

With the emergence of Plasmodium falciparum infections exhibiting increased parasite clearance times in response to treatment with artemisinin-based combination therapies, the need for new therapeutic agents is urgent. Solithromycin, a potent new fluoroketolide currently in development, has been shown to be an effective, broad-spectrum antimicrobial agent. Malarial parasites possess an unusual organelle, termed the apicoplast, which carries a cryptic genome of prokaryotic origin that encodes its own translation and transcription machinery. Given the similarity of apicoplast and bacterial ribosomes, we have examined solithromycin for antimalarial activity. Other antibiotics known to target the apicoplast, such as the macrolide azithromycin, demonstrate a delayed-death effect, whereby treated asexual blood-stage parasites die in the second generation of drug exposure. Solithromycin demonstrated potent in vitro activity against the NF54 strain of P. falciparum, as well as against two multidrug-resistant strains, Dd2 and 7G8. The dramatic increase in potency observed after two generations of exposure suggests that it targets the apicoplast. Solithromycin also retained potency against azithromycin-resistant parasites derived from Dd2 and 7G8, although these lines did demonstrate a degree of cross-resistance. In an in vivo model of P. berghei infection in mice, solithromycin demonstrated a 100% cure rate when administered as a dosage regimen of four doses of 100 mg/kg of body weight, the same dose required for artesunate or chloroquine to achieve 100% cure rates in this rodent malaria model. These promising in vitro and in vivo data support further investigations into the development of solithromycin as an antimalarial agent.


Asunto(s)
Antimaláricos/farmacología , Macrólidos/farmacología , Malaria/tratamiento farmacológico , Plasmodium berghei/efectos de los fármacos , Plasmodium falciparum/efectos de los fármacos , Triazoles/farmacología , Animales , Antimaláricos/uso terapéutico , Resistencia a Múltiples Medicamentos , Humanos , Macrólidos/uso terapéutico , Malaria/mortalidad , Malaria/parasitología , Ratones , Pruebas de Sensibilidad Parasitaria , Plasmodium falciparum/fisiología , Triazoles/uso terapéutico
14.
Clin Infect Dis ; 52 Suppl 7: S520-6, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21546629

RESUMEN

Fusidic acid (CEM-102), an orally bioavailable fusidane antibiotic with a unique mode of action, is under development for treatment of acute gram-positive bacterial skin and skin structure infections, including those caused by methicillin-susceptible and methicillin-resistant Staphylococcus aureus and streptococci. A phase 2, adaptive design, randomized, double-blind, multiple-center study of 198 adult patients with cellulitis or wound infections was conducted to evaluate an oral CEM-102 loading-dose regimen (1500 mg twice per day on day 1 followed by 600 mg twice per day) compared with oral linezolid (600 mg twice per day) administered for 10-14 days. The CEM-102 loading-dose regimen demonstrated efficacy, safety, and tolerability that was comparable to linezolid for the treatment of acute gram-positive bacterial skin and skin structure infections. Clinical Trials registration. NCT00948142.


Asunto(s)
Antibacterianos/efectos adversos , Antibacterianos/uso terapéutico , Ácido Fusídico/efectos adversos , Ácido Fusídico/uso terapéutico , Cocos Grampositivos/efectos de los fármacos , Enfermedades Cutáneas Bacterianas/tratamiento farmacológico , Acetamidas/administración & dosificación , Acetamidas/efectos adversos , Acetamidas/uso terapéutico , Enfermedad Aguda , Administración Oral , Adulto , Antibacterianos/administración & dosificación , Antibacterianos/farmacología , Celulitis (Flemón)/tratamiento farmacológico , Celulitis (Flemón)/microbiología , Método Doble Ciego , Esquema de Medicación , Femenino , Ácido Fusídico/administración & dosificación , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Infecciones por Bacterias Grampositivas/microbiología , Humanos , Linezolid , Masculino , Persona de Mediana Edad , Oxazolidinonas/administración & dosificación , Oxazolidinonas/efectos adversos , Oxazolidinonas/uso terapéutico , Enfermedades Cutáneas Bacterianas/microbiología , Resultado del Tratamiento , Adulto Joven
15.
Proc Natl Acad Sci U S A ; 108(11): 4400-5, 2011 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-21300861

RESUMEN

Ozonide OZ439 is a synthetic peroxide antimalarial drug candidate designed to provide a single-dose oral cure in humans. OZ439 has successfully completed Phase I clinical trials, where it was shown to be safe at doses up to 1,600 mg and is currently undergoing Phase IIa trials in malaria patients. Herein, we describe the discovery of OZ439 and the exceptional antimalarial and pharmacokinetic properties that led to its selection as a clinical drug development candidate. In vitro, OZ439 is fast-acting against all asexual erythrocytic Plasmodium falciparum stages with IC(50) values comparable to those for the clinically used artemisinin derivatives. Unlike all other synthetic peroxides and semisynthetic artemisinin derivatives, OZ439 completely cures Plasmodium berghei-infected mice with a single oral dose of 20 mg/kg and exhibits prophylactic activity superior to that of the benchmark chemoprophylactic agent, mefloquine. Compared with other peroxide-containing antimalarial agents, such as the artemisinin derivatives and the first-generation ozonide OZ277, OZ439 exhibits a substantial increase in the pharmacokinetic half-life and blood concentration versus time profile in three preclinical species. The outstanding efficacy and prolonged blood concentrations of OZ439 are the result of a design strategy that stabilizes the intrinsically unstable pharmacophoric peroxide bond, thereby reducing clearance yet maintaining the necessary Fe(II)-reactivity to elicit parasite death.


Asunto(s)
Adamantano/análogos & derivados , Antimaláricos/administración & dosificación , Antimaláricos/uso terapéutico , Compuestos Heterocíclicos/administración & dosificación , Compuestos Heterocíclicos/uso terapéutico , Malaria/tratamiento farmacológico , Peróxidos/administración & dosificación , Peróxidos/uso terapéutico , Adamantano/administración & dosificación , Adamantano/química , Adamantano/farmacocinética , Adamantano/uso terapéutico , Animales , Antimaláricos/química , Antimaláricos/farmacocinética , Artemisininas/química , Artemisininas/farmacología , Artemisininas/uso terapéutico , Relación Dosis-Respuesta a Droga , Estabilidad de Medicamentos , Compuestos Heterocíclicos/química , Compuestos Heterocíclicos/farmacocinética , Hierro/metabolismo , Malaria/parasitología , Masculino , Ratones , Peróxidos/química , Peróxidos/farmacocinética , Plasmodium berghei/fisiología , Ratas , Ratas Sprague-Dawley , Factores de Tiempo , Resultado del Tratamiento
16.
Reprod Toxicol ; 30(4): 583-90, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20708075

RESUMEN

Three groups of compounds: (i) active peroxides (artemisinin and arterolene), (ii) inactive non-peroxidic derivatives (deoxyartemisinin and carbaOZ277) and (iii) inactive peroxide (OZ381) were tested by WEC system to provide insights into the relationship between chemical structure and embryotoxic potential, and to assess the relationship between embryotoxicity and antimalarial activity. Deoxyartemisinin, OZ381 and carbaOZ277 did not affect rat embryonic development. Artemisinin and arterolane affected primarily nucleated red blood cells (RBCs), inducing anemia and subsequent tissue damage in rat embryos, with NOELs for RBC damage at 0.1 and 0.175µg/mL, respectively. These data support the idea that only active antimalarial peroxides are able to interfere with normal embryonic development. In an attempt to establish whether and to what extent activity as antimalarials and embryotoxicity can be divorced, IC(50)s for activity in Plasmodium falciparum strains and the NOELs for RBCs were compared. From this comparison, arterolane showed a better safety margin than artemisinin.


Asunto(s)
Antimaláricos/toxicidad , Embrión de Mamíferos/efectos de los fármacos , Peróxidos/toxicidad , Teratógenos/toxicidad , Adamantano/análogos & derivados , Adamantano/toxicidad , Animales , Antimaláricos/química , Artemisininas/toxicidad , Región Branquial/efectos de los fármacos , Región Branquial/patología , Evaluación Preclínica de Medicamentos/métodos , Técnicas de Cultivo de Embriones , Embrión de Mamíferos/irrigación sanguínea , Embrión de Mamíferos/patología , Desarrollo Embrionario/efectos de los fármacos , Eritrocitos/efectos de los fármacos , Eritrocitos/patología , Compuestos Heterocíclicos con 1 Anillo/química , Compuestos Heterocíclicos con 1 Anillo/toxicidad , Concentración 50 Inhibidora , Nivel sin Efectos Adversos Observados , Peróxidos/química , Plasmodium falciparum/efectos de los fármacos , Ratas , Compuestos de Espiro/química , Compuestos de Espiro/toxicidad , Relación Estructura-Actividad , Teratógenos/química , Saco Vitelino/irrigación sanguínea , Saco Vitelino/efectos de los fármacos , Saco Vitelino/patología
17.
Malar J ; 8: 304, 2009 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-20021657

RESUMEN

BACKGROUND: The population pharmacokinetics of artesunate (AS) and its active metabolite dihydroartemisinin (DHA) were studied in healthy subjects receiving single- or multiple-dosing of AS orally either in combination with pyronaridine (PYR) or as a monotherapy with or without food. METHODS: Data from 118 concentration-time profiles arising from 91 healthy Korean subjects were pooled from four Phase I clinical studies. Subjects received 2-5 mg/kg of single- and multiple-dosing of oral AS either in combination with PYR or as a monotherapy with or without food. Plasma AS and DHA were measured simultaneously using a validated liquid chromatography- mass spectrometric method with a lower limit of quantification of 1 ng/mL for both AS and DHA. Nonlinear mixed-effect modelling was used to obtain the pharmacokinetic and variability (inter-individual and residual variability) parameter estimates. RESULTS: A novel parent-metabolite pharmacokinetic model consisting of a dosing compartment, a central compartment for AS, a central compartment and a peripheral compartment for DHA was developed. AS and DHA data were modelled simultaneously assuming stoichiometric conversion to DHA. AS was rapidly absorbed with a population estimate of absorption rate constant (Ka) of 3.85 h-1. The population estimates of apparent clearance (CL/F) and volume of distribution (V2/F) for AS were 1190 L/h with 36.2% inter-individual variability (IIV) and 1210 L with 57.4% IIV, respectively. For DHA, the population estimates of apparent clearance (CLM/F) and central volume of distribution (V3/F) were 93.7 L/h with 28% IIV and 97.1 L with 30% IIV, respectively. The population estimates of apparent inter-compartmental clearance (Q/F) and peripheral volume of distribution (V4/F) for DHA were 5.74 L/h and 18.5 L, respectively. Intake of high-fat and high-caloric meal prior to the drug administration resulted in 84% reduction in Ka. Body weight impacted CLM/F, such that a unit change in weight resulted in 1.9-unit change in CLM/F in the same direction. CONCLUSIONS: A novel simultaneous parent-metabolite pharmacokinetic model with good predictive power was developed to study the population pharmacokinetics of AS and DHA in healthy subjects following single- and multiple-dosing of AS with or without the presence of food. Food intake and weight were significant covariates for Ka and CLM/F, respectively.


Asunto(s)
Antimaláricos/administración & dosificación , Antimaláricos/farmacocinética , Artemisininas/administración & dosificación , Artemisininas/farmacocinética , Administración Oral , Adulto , Artesunato , Cromatografía Liquida/métodos , Ingestión de Alimentos , Femenino , Humanos , Masculino , Espectrometría de Masas/métodos , Modelos Estadísticos , Naftiridinas/administración & dosificación , Plasma/química , República de Corea , Adulto Joven
18.
Curr Opin Microbiol ; 11(5): 428-33, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18824124

RESUMEN

Malaria is a significant cause of morbidity and mortality in the developing world. Until recently malaria was winning but with increase in funding particularly from philanthropic groups the ability to control malaria is again possible. There are still many challenges to developing the next generations of anti-malarials. This article will briefly discuss the challenges and the advance that are being made.


Asunto(s)
Antimaláricos/farmacología , Descubrimiento de Drogas/tendencias , Plasmodium/efectos de los fármacos , Animales , Países en Desarrollo , Quimioterapia Combinada , Humanos , Malaria/tratamiento farmacológico , Malaria/prevención & control
19.
Mar Environ Res ; 62 Suppl: S128-35, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16712918

RESUMEN

The lack of genomic resources for aquatic invertebrates restricts their use as sentinel species in coastal environments. It is known that where genomic data are not available, suppression subtractive hybridisation (SSH) can generate cDNA libraries representative of pollutant-responsive gene transcription in aquatic vertebrates. To assess whether the approach was equally suited to aquatic invertebrates, altered gene expression in digestive gland of the mussel, Mytilus edulis, in response to exposure to benzo[a]pyrene (BaP) (1 mg/l) was investigated with SSH and a nylon macroarray. Screening of the subtracted libraries showed 112/250 up-regulated and 25/55 down-regulated clones were positive for differential expression and characterisation of these identified 87 with unique sequence suitable for array on a nylon membrane. The transcripts isolated were from a diverse range of genes involved in general stress, oxidative stress, cell adhesion, transcriptional and translational regulation, transport mechanisms, energy metabolism, cell metabolism, lipid metabolism, protein turnover and activation, lysosomal activity and 22 cryptic clones. Subsequent use of the clones in macroarray format to analyse expression of BaP-responsive genes (0 vs 4 day exposed) showed 0-100-fold increased levels of the forward-subtracted probes and between 0 and 0.1-fold down-regulation of the reverse-subtracted probes. Only 15% of the clones showed less than 2-fold change in expression. The gene ontology of the transcripts isolated demonstrates that BaP elicits a multitude of responses with a major feature being disruption of cellular redox status. The results indicate that the use of SSH and a macroarray is a robust method to discover novel pollutant-responsive genes in aquatic invertebrates.


Asunto(s)
Benzo(a)pireno/toxicidad , Expresión Génica/efectos de los fármacos , Mytilus edulis/efectos de los fármacos , Hibridación de Ácido Nucleico/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Contaminantes Químicos del Agua/toxicidad , Animales , ADN Complementario/clasificación , ADN Complementario/aislamiento & purificación , Sistema Digestivo/efectos de los fármacos , Exposición a Riesgos Ambientales , Femenino , Biblioteca de Genes , Masculino , Mytilus edulis/fisiología , Factores de Tiempo
20.
Proc Natl Acad Sci U S A ; 102(40): 14410-5, 2005 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-16186482

RESUMEN

Macrophage migration inhibitory factor (MIF) is an immunologic regulator that is expressed in inflammatory and autoimmune disorders. We investigated MIF's role in asthma using genetic approaches in a mouse model and in a cohort of asthma patients. Mice genetically deficient in MIF that were primed and aerosol-challenged with ovalbumin showed less pulmonary inflammation and lower airway hyperresponsiveness than genetically matched, wild-type controls. MIF deficiency also resulted in lower titers of specific IgE, IgG(1), and IgG(2a), and decreased pulmonary, T(H)2 cytokine levels. IL-5 concentrations were lower and corresponded to decreased eosinophil numbers in bronchoalveolar lavage fluid. T cell studies also showed a lower level of antigen-specific responses in MIF-KO versus wild-type mice. In an analysis of 151 white patients with mild, moderate, or severe asthma (Global Initiative for Asthma criteria), a significant association was found between mild asthma and the low-expression, 5-CATT MIF allele. Pharmacologic inhibition of MIF may be beneficial and could be guided by the MIF genotype of affected individuals.


Asunto(s)
Asma/inmunología , Asma/metabolismo , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Adulto , Animales , Secuencia de Bases , Lavado Broncoalveolar , Proliferación Celular , Células Cultivadas , Citocinas/metabolismo , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Componentes del Gen , Genotipo , Humanos , Interleucina-5/metabolismo , Oxidorreductasas Intramoleculares , Factores Inhibidores de la Migración de Macrófagos/genética , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Ovalbúmina , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Linfocitos T Colaboradores-Inductores/metabolismo
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