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1.
J Viral Hepat ; 28(8): 1169-1176, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34002927

RESUMEN

Various non-invasive methods have been evaluated in chronic hepatitis B, but none of them have been fully validated for the assessment of liver fibrosis. The issued EASL-ALEH 2015 guidelines provide detailed algorithms based on LSM and ALT serum levels. The aim of our study was to validate the diagnostic accuracy of this algorithm and to better understand discrepancies. Four hundred and thirteen patients from 3 centres were retrospectively included. All included patients were classified for fibrosis stage according to results of a liver biopsy. The overall diagnostic value was expressed with AUROCs given with 95% confidence intervals for the diagnostic targets. For each diagnostic target, optimal cut-offs were determined according to the Youden method. For the population of patients with ALT9 kPa, respectively. For patients with ALT>N but ≤5N (n = 306), AUROCs of transient elastography were 0.79 (0.73-0.84) and 0.84 (0.75-0.92) for F ≥ 2 and F ≥ 3 diagnostic targets. The prevalence of significant fibrosis was, respectively, 15%, 52% and 85% when LSM was <6kPa, between 6 and 12 kPa or >12 kPa. Our study independently validates the EASL-ALEH algorithm based on ALT levels and LSM assessed by transient elastography.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Hepatitis B Crónica , Algoritmos , Biopsia , Hepatitis B Crónica/complicaciones , Hepatitis B Crónica/diagnóstico por imagen , Hepatitis B Crónica/patología , Humanos , Hígado/diagnóstico por imagen , Hígado/patología , Cirrosis Hepática/diagnóstico por imagen , Cirrosis Hepática/patología , Estudios Retrospectivos
2.
Arch Toxicol ; 94(11): 3877-3891, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32691075

RESUMEN

Organophosphorus (OP) compounds inhibit central and peripheral acetylcholinesterase (AChE) activity, overstimulating cholinergic receptors and causing autonomic dysfunction (e.g., bronchoconstriction, excess secretions), respiratory impairment, seizure and death at high doses. Current treatment for OP poisoning in the United States includes reactivation of OP-inhibited AChE by the pyridinium oxime 2-pyridine aldoxime (2-PAM). However, 2-PAM has a narrow therapeutic index and its efficacy is confined to a limited number of OP agents. The bis-pyridinium oxime MMB4, which is a more potent reactivator than 2-PAM with improved pharmaceutical properties and therapeutic range, is under consideration as a potential replacement for 2-PAM. Similar to other pyridinium oximes, high doses of MMB4 lead to off-target effects culminating in respiratory depression and death. To understand the toxic mechanisms contributing to respiratory depression, we evaluated the effects of MMB4 (0.25-16 mM) on functional and neurophysiological parameters of diaphragm and limb muscle function in rabbits and rats. In both species, MMB4 depressed nerve-elicited muscle contraction by blocking muscle endplate nicotinic receptor currents while simultaneously prolonging endplate potentials by inhibiting AChE. MMB4 increased quantal content, endplate potential rundown and tetanic fade during high frequency stimulation in rat but not rabbit muscles, suggesting species-specific effects on feedback mechanisms involved in sustaining neurotransmission. These data reveal multifactorial effects of MMB4 on cholinergic neurotransmission, with the primary toxic modality being reduced muscle nicotinic endplate currents. Evidence of species-specific effects on neuromuscular function illustrates the importance of comparative toxicology when studying pyridinium oximes and, by inference, other quaternary ammonium compounds.


Asunto(s)
Acetilcolinesterasa/efectos de los fármacos , Músculos/efectos de los fármacos , Intoxicación por Organofosfatos/tratamiento farmacológico , Oximas/efectos adversos , Transmisión Sináptica/efectos de los fármacos , Animales , Reactivadores de la Colinesterasa/efectos adversos , Relación Dosis-Respuesta a Droga , Femenino , Masculino , Compuestos de Pralidoxima/uso terapéutico , Conejos , Ratas , Ratas Sprague-Dawley , Insuficiencia Respiratoria/inducido químicamente , Especificidad de la Especie
3.
Sensors (Basel) ; 20(12)2020 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-32585862

RESUMEN

The first goal of this study is to identify the ideal piezoelectric material for the manufacturing of rheological reflectance ultrasonic sensors. The second goal is to integrate the ultrasonic rheometer within a gas absorption reactor and to measure viscosity changes in an ionic liquid (IL) caused by gas absorption. To achieve the objectives, bismuth titanate, lead titanate, lead metaniobate and lead zirconate titanate materials in layer, tungsten bronze and perovskite structures were assembled on aluminum delay lines and tested under thermal cycling between room temperature and 150 °C. The results showed that lead metaniobate in tungsten bronze structure is the most suitable material for long time duration thermal cycling. Therefore, the ultrasonic rheometer was assembled using this material and installed in a pressurized reactor to test a reference IL at the operating conditions of 50 °C and at a pressure of 80 bar. The reference IL was saturated with nitrogen as well as hydrogen gas. Viscosity signals remained constant under the hydrogen atmosphere, while in nitrogen atmosphere the absorption of the gas lead to a rise in the value of viscosity.

4.
Appl Environ Microbiol ; 84(24)2018 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-30389764

RESUMEN

Botulinum neurotoxins (BoNTs), the most poisonous proteins known to humankind, are a family of seven (serotype A to G) immunologically distinct proteins synthesized primarily by different strains of the anaerobic bacterium Clostridium botulinum Being the causative agents of botulism, the toxins block neurotransmitter release by specifically cleaving one of the three soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) proteins, thereby inducing flaccid paralysis. The development of countermeasures and therapeutics against BoNTs is a high-priority research area for public health because of their extreme toxicity and potential for use as biowarfare agents. Extensive research has focused on designing antagonists that block the catalytic activity of BoNTs. In this study, we screened 300 small natural compounds and their analogues extracted from Indian plants for their activity against BoNT serotype A (BoNT/A) as well as its light chain (LCA) using biochemical and cellular assays. One natural compound, a nitrophenyl psoralen (NPP), was identified to be a specific inhibitor of LCA with an in vitro 50% inhibitory concentration (IC50) value of 4.74 ± 0.03 µM. NPP was able to rescue endogenous synaptosome-associated protein 25 (SNAP-25) from cleavage by BoNT/A in human neuroblastoma cells with an IC50 of 12.2 ± 1.7 µM, as well as to prolong the time to the blocking of neutrally elicited twitch tensions in isolated mouse phrenic nerve-hemidiaphragm preparations.IMPORTANCE The long-lasting endopeptidase activity of BoNT is a critical biological activity inside the nerve cell, as it prompts proteolysis of the SNARE proteins, involved in the exocytosis of the neurotransmitter acetylcholine. Thus, the BoNT endopeptidase activity is an appropriate clinical target for designing new small-molecule antidotes against BoNT with the potential to reverse the paralysis syndrome of botulism. In principle, small-molecule inhibitors (SMIs) can gain entry into BoNT-intoxicated cells if they have a suitable octanol-water partition coefficient (log P) value and other favorable characteristics (P. Leeson, Nature 481:455-456, 2012, https://doi.org/10.1038/481455a). Several efforts have been made in the past to develop SMIs, but inhibitors effective under in vitro conditions have not in general been effective in vivo or in cellular models (L. M. Eubanks, M. S. Hixon, W. Jin, S. Hong, et al., Proc Natl Acad Sci U S A 104:2602-2607, 2007, https://doi.org/10.1073/pnas.0611213104). The difference between the in vitro and cellular efficacy presumably results from difficulties experienced by the compounds in crossing the cell membrane, in conjunction with poor bioavailability and high cytotoxicity. The screened nitrophenyl psoralen (NPP) effectively antagonized BoNT/A in both in vitro and ex vivo assays. Importantly, NPP inhibited the BoNT/A light chain but not other general zinc endopeptidases, such as thermolysin, suggesting high selectivity for its target. Small-molecule (nonpeptidic) inhibitors have better oral bioavailability, better stability, and better tissue and cell permeation than antitoxins or peptide inhibitors.


Asunto(s)
Antídotos/farmacología , Antídotos/uso terapéutico , Antitoxinas/farmacología , Antitoxinas/uso terapéutico , Toxinas Bacterianas/antagonistas & inhibidores , Animales , Toxinas Botulínicas Tipo A/antagonistas & inhibidores , Línea Celular Tumoral/efectos de los fármacos , Clostridium botulinum , Modelos Animales de Enfermedad , Endopeptidasas , Ensayos Analíticos de Alto Rendimiento , Humanos , India , Concentración 50 Inhibidora , Masculino , Ratones , Neuroblastoma/tratamiento farmacológico , Extractos Vegetales/farmacología , Proteínas SNARE/metabolismo , Proteína 25 Asociada a Sinaptosomas/metabolismo , Termolisina
5.
Biochem Biophys Res Commun ; 488(2): 311-315, 2017 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-28483527

RESUMEN

Immuno-PCR (IPCR) combines the versatile ELISA antigen detection with ultrasensitive PCR signal amplification, thereby enabling the highly sensitive detection of a broad range of targets with a typically very large dynamic detection range. The quantification of the antigen is usually achieved by real-time PCR, which provides a correlation between the target concentration and amplified DNA marker. We here report on the implementation of digital droplet PCR as a means for direct quantification of DNA copies to enable the highly sensitive detection of protein biomarkers. To this end, two alternative approaches, based on either magnetic microbead-based IPCR or a microplate-release IPCR were tested. The latter format worked well and revealed an extraordinary high robustness and sensitivity. While rtIPCR already fulfills typical immunoassay acceptance criteria, ddIPCR enables improved accuracy and precision of the assay because signal response and analyte concentrations are directly correlated. The utility of the novel ddIPCR technology is demonstrated at the example of two cytokines, interleukin 2 and interleukin 6 (IL2, IL6, respectively), with an overall average CV% of 5.0 (IL2) and 7.4 (IL6).


Asunto(s)
Antígenos/análisis , Citocinas/análisis , Inmunoensayo/métodos , Reacción en Cadena de la Polimerasa/métodos , Inmunoensayo/instrumentación , Tamaño de la Partícula , Reacción en Cadena de la Polimerasa/instrumentación
6.
Am J Perinatol ; 34(9): 851-855, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28231602

RESUMEN

Objective The objective of this study was to observe the efficacy of antiemetic therapy (no emesis/retching episodes and no rescue medication use) when granisetron is administered via a transdermal patch system (TDS) in women who are 6 to 14 weeks pregnant when compared with oral ondansetron by evaluating the frequency of the use of rescue medications for control of nausea/vomiting of pregnancy (NVP). Methods This was an observational case series study to observe the potential benefits of granisetron TDS compared with oral ondansetron for management of NVP in pregnant patients during the first trimester. Dates of data collection were September 1, 2014, through December 31, 2015. There was no direct contact with patient. The oral ondansetron and granisetron TDS patients were matched by age, 4:1. The proportion of patients who received rescue antiemetics was calculated from those patients who continued to experience NVP. Risk factors for NVP were identified and compared between groups. Descriptive statistics were used to describe study results. Results Patients were prescribed rescue antiemetics in 0/3 patients in the granisetron TDS group compared with 2/12 patients in the oral ondansetron group. Conclusion Prospective efficacy studies on the use of granisetron TDS for management of NVP are needed to confirm this clinical observation.


Asunto(s)
Antieméticos/administración & dosificación , Granisetrón/administración & dosificación , Náuseas Matinales/tratamiento farmacológico , Parche Transdérmico , Administración Oral , Adulto , Femenino , Humanos , Ondansetrón/administración & dosificación , Embarazo , Texas , Resultado del Tratamiento
7.
PLoS Pathog ; 10(7): e1004177, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25010769

RESUMEN

Botulinum neurotoxins (BoNT/A-G), the most potent toxins known, act by cleaving three SNARE proteins required for synaptic vesicle exocytosis. Previous studies on BoNTs have generally utilized the major SNARE homologues expressed in brain (VAMP2, syntaxin 1, and SNAP-25). However, BoNTs target peripheral motor neurons and cause death by paralyzing respiratory muscles such as the diaphragm. Here we report that VAMP1, but not VAMP2, is the SNARE homologue predominantly expressed in adult rodent diaphragm motor nerve terminals and in differentiated human motor neurons. In contrast to the highly conserved VAMP2, BoNT-resistant variations in VAMP1 are widespread across vertebrates. In particular, we identified a polymorphism at position 48 of VAMP1 in rats, which renders VAMP1 either resistant (I48) or sensitive (M48) to BoNT/D. Taking advantage of this finding, we showed that rat diaphragms with I48 in VAMP1 are insensitive to BoNT/D compared to rat diaphragms with M48 in VAMP1. This unique intra-species comparison establishes VAMP1 as a physiological toxin target in diaphragm motor nerve terminals, and demonstrates that the resistance of VAMP1 to BoNTs can underlie the insensitivity of a species to members of BoNTs. Consistently, human VAMP1 contains I48, which may explain why humans are insensitive to BoNT/D. Finally, we report that residue 48 of VAMP1 varies frequently between M and I across seventeen closely related primate species, suggesting a potential selective pressure from members of BoNTs for resistance in vertebrates.


Asunto(s)
Toxinas Botulínicas/toxicidad , Variación Genética , Proteína 1 de Membrana Asociada a Vesículas , Secuencia de Aminoácidos , Animales , Diafragma/inervación , Diafragma/metabolismo , Diafragma/patología , Humanos , Masculino , Ratones , Datos de Secuencia Molecular , Neuronas Motoras/metabolismo , Neuronas Motoras/patología , Paresia/inducido químicamente , Paresia/genética , Paresia/metabolismo , Paresia/patología , Ratas , Ratas Sprague-Dawley , Especificidad de la Especie , Proteína 1 de Membrana Asociada a Vesículas/genética , Proteína 1 de Membrana Asociada a Vesículas/metabolismo
8.
Pharm Res ; 33(2): 450-61, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26474763

RESUMEN

PURPOSE: The current study was performed to assess the precision of the principal subvisible particle measurement methods available today. Special attention was given to identifying the sources of error and the factors governing analytical performance. METHODS: The performance of individual techniques was evaluated using a commercial biologic drug product in a prefilled syringe container. In control experiments, latex spheres were used as standards and instrument calibration suspensions. RESULTS: The results reported in this manuscript clearly demonstrated that the particle measurement techniques operating in the submicrometer range have much lower precision than the micrometer size-range methods. It was established that the main factor governing the relatively poor precision of submicrometer methods in general and inherently, is their low sampling volume and the corresponding large extrapolation factors for calculating final results. CONCLUSIONS: The variety of new methods for submicrometer particle analysis may in the future support product characterization; however, the performance of the existing methods does not yet allow for their use in routine practice and quality control.


Asunto(s)
Técnicas de Química Analítica/métodos , Proteínas/química , Tamaño de la Partícula , Agregado de Proteínas , Jeringas
9.
Dig Dis Sci ; 61(3): 846-51, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26362282

RESUMEN

BACKGROUND: Antibiotics for presumed small intestinal bacterial overgrowth have been shown to improve irritable bowel syndrome symptoms in at least 40% of subjects. A lactulose breath test for small intestinal bacterial overgrowth has been used to select patients who will respond. However, its predictive value, using the classic definition of a positive lactulose breath test, has been disappointing. AIMS: We conducted a retrospective evaluation to study characteristics of the lactulose breath test that may be predictive of a response to antibiotics in patients with the irritable bowel syndrome. METHODS: A clinical practice database was interrogated for consecutive patients who had a lactulose breath test for irritable bowel syndrome symptoms and a subsequent antibiotic course. Hydrogen + methane levels with carbon dioxide correction were plotted against time. Various profiles of the breath test curves were catalogued and compared with respect to their predictive value for symptom response to antibiotics. RESULTS: Lactulose breath test graphs of 561 patients of all irritable bowel syndrome subtypes were grouped into categories based on their hydrogen + methane levels with respect to time. Of subjects whose hydrogen + methane rise was <20 ppm throughout the test (group 1; N = 95), 94.7% improved after antibiotics (95% CI 90.1-99.3). Of those with a rise <20 ppm within the first 90 min but a rise >50 ppm thereafter (group 3; N = 53), 47.2% improved (95% CI 33.7-60.6). The difference between groups 1 and 3 was statistically significant P < 0.001. CONCLUSION: A lactulose breath test appears to be useful in predicting response to antibiotics in patients with the irritable bowel syndrome. A hydrogen + methane rise <20 ppm throughout the duration of the test is most predictive. This observation contradicts the classic definition of a positive lactulose breath test.


Asunto(s)
Antibacterianos/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Estreñimiento/tratamiento farmacológico , Diarrea/tratamiento farmacológico , Microbioma Gastrointestinal , Síndrome del Colon Irritable/tratamiento farmacológico , Adulto , Anciano , Infecciones Bacterianas/complicaciones , Pruebas Respiratorias , Estreñimiento/etiología , Estreñimiento/microbiología , Diarrea/etiología , Diarrea/microbiología , Femenino , Humanos , Hidrógeno/análisis , Síndrome del Colon Irritable/complicaciones , Síndrome del Colon Irritable/microbiología , Lactulosa , Masculino , Metano/análisis , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
10.
Anal Chem ; 87(12): 6119-24, 2015 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-26001042

RESUMEN

Although light obscuration is the "gold standard" for subvisible particle measurements in biopharmaceutical products, the current technology has limitations with respect to the detection of translucent proteinaceous particles and particles of sizes smaller and around 2 µm. Here, we describe the evaluation of a modified light obscuration sensor utilizing a novel measuring mode. Whereas standard light obscuration methodology monitors the height (amplitude) of the signal, the new approach monitors its length (width). Experimental evaluation demonstrated that this new detection mode leads to improved detection of subvisible particles of sizes smaller than 2 µm, reduction of artifacts during measurements especially of low concentrations of translucent protein particles, and higher counting accuracy as compared to flow imaging microscopy and standard light obscuration measurements.


Asunto(s)
Luz , Albúmina Sérica Bovina/química , Animales , Bovinos , Nefelometría y Turbidimetría/instrumentación , Tamaño de la Partícula , Propiedades de Superficie
11.
Analyst ; 140(18): 6175-94, 2015 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-26196036

RESUMEN

Recombinant DNA technology and corresponding innovations in molecular biology, chemistry and medicine have led to novel therapeutic biomacromolecules as lead candidates in the pharmaceutical drug development pipelines. While monoclonal antibodies and other proteins provide therapeutic potential beyond the possibilities of small molecule drugs, the concomitant demand for supportive bioanalytical sample testing creates multiple novel challenges. For example, intact macromolecules can usually not be quantified by mass-spectrometry without enzymatic digestion and isotopically labeled internal standards are costly and/or difficult to prepare. Classical ELISA-type immunoassays, on the other hand, often lack the sensitivity required to obtain pharmacokinetics of low dosed drugs or pharmacodynamics of suitable biomarkers. Here we summarize emerging state-of-the-art ligand-binding assay technologies for pharmaceutical sample testing, which reveal enhanced analytical sensitivity over classical ELISA formats. We focus on immuno-PCR, which combines antibody specificity with the extremely sensitive detection of a tethered DNA marker by quantitative PCR, and alternative nucleic acid-based technologies as well as methods based on electrochemiluminescence or single-molecule counting. Using case studies, we discuss advantages and drawbacks of these methods for preclinical and clinical sample testing.


Asunto(s)
Inmunoensayo/métodos , Límite de Detección , Reacción en Cadena de la Polimerasa/métodos , Animales , Especificidad de Anticuerpos , ADN/análisis , ADN/genética , Humanos , Ligandos
12.
Bioorg Med Chem ; 23(22): 7264-73, 2015 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-26522088

RESUMEN

The seven antigenically distinct serotypes (A-G) of botulinum neurotoxin (BoNT) are responsible for the deadly disease botulism. BoNT serotype A (BoNT/A) exerts its lethal action by cleaving the SNARE protein SNAP-25, leading to inhibition of neurotransmitter release, flaccid paralysis and autonomic dysfunction. BoNTs are dichain proteins consisting of a ∼ 100 kDa heavy chain and a ∼ 50 kDa light chain; the former is responsible for neurospecific binding, internalization and translocation, and the latter for cleavage of neuronal SNARE proteins. Because of their extreme toxicity and history of weaponization, the BoNTs are regarded as potential biowarfare/bioterrorism agents. No post-symptomatic therapeutic interventions are available for BoNT intoxication other than intensive care; therefore it is imperative to develop specific antidotes against this neurotoxin. To this end, a cyclic peptide inhibitor (CPI-1) was evaluated in a FRET assay for its ability to inhibit BoNT/A light chain (Balc). CPI was found to be highly potent, exhibiting a Ki of 12.3 nM with full-length Balc448 and 39.2 nM using a truncated crystallizable form of the light chain (Balc424). Cocrystallization studies revealed that in the Balc424-CPI-1 complex, the inhibitor adopts a helical conformation, occupies a high percentage of the active site cavity and interacts in an amphipathic manner with critical active site residues. The data suggest that CPI-1 prevents SNAP-25 from accessing the Balc active site by blocking both the substrate binding path at the surface and the Zn(2+) binding region involved in catalysis. This differs from linear peptide inhibitors described to date which block only the latter.


Asunto(s)
Toxinas Botulínicas Tipo A/antagonistas & inhibidores , Toxinas Botulínicas Tipo A/química , Péptidos Cíclicos/química , Sitios de Unión , Toxinas Botulínicas Tipo A/metabolismo , Dominio Catalítico , Cristalografía por Rayos X , Humanos , Simulación de Dinámica Molecular , Péptidos Cíclicos/metabolismo , Unión Proteica , Proteína 25 Asociada a Sinaptosomas/metabolismo
13.
N Engl J Med ; 365(11): 1014-24, 2011 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-21916639

RESUMEN

BACKGROUND: Patients with chronic infection with hepatitis C virus (HCV) genotype 1 often need 48 weeks of peginterferon-ribavirin treatment for a sustained virologic response. We designed a noninferiority trial (noninferiority margin, -10.5%) to compare rates of sustained virologic response among patients receiving two treatment durations. METHODS: We enrolled patients with chronic infection with HCV genotype 1 who had not previously received treatment. All patients received telaprevir at a dose of 750 mg every 8 hours, peginterferon alfa-2a at a dose of 180 µg per week, and ribavirin at a dose of 1000 to 1200 mg per day, for 12 weeks (T12PR12), followed by peginterferon-ribavirin. Patients who had an extended rapid virologic response (undetectable HCV RNA levels at weeks 4 and 12) were randomly assigned after week 20 to receive the dual therapy for 4 more weeks (T12PR24) or 28 more weeks (T12PR48). Patients without an extended rapid virologic response were assigned to T12PR48. RESULTS: Of the 540 patients, a total of 352 (65%) had an extended rapid virologic response. The overall rate of sustained virologic response was 72%. Among the 322 patients with an extended rapid virologic response who were randomly assigned to a study group, 149 (92%) in the T12PR24 group and 140 (88%) in the T12PR48 group had a sustained virologic response (absolute difference, 4 percentage points; 95% confidence interval, -2 to 11), establishing noninferiority. Adverse events included rash (in 37% of patients, severe in 5%) and anemia (in 39%, severe in 6%). Discontinuation of all the study drugs was based on adverse events in 18% of patients overall, as well as in 1% of patients (all of whom were randomly assigned) in the T12PR24 group and 12% of the patients randomly assigned to the T12PR48 group (P<0.001). CONCLUSIONS: In this study, among patients with chronic HCV infection who had not received treatment previously, a regimen of peginterferon-ribavirin for 24 weeks, with telaprevir for the first 12 weeks, was noninferior to the same regimen for 48 weeks in patients with undetectable HCV RNA at weeks 4 and 12, with an extended rapid virologic response achieved in nearly two thirds of patients. (Funded by Vertex Pharmaceuticals and Tibotec; ILLUMINATE ClinicalTrials.gov number, NCT00758043.).


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C/tratamiento farmacológico , Oligopéptidos/uso terapéutico , Adulto , Anciano , Anemia/inducido químicamente , Antivirales/efectos adversos , Quimioterapia Combinada , Exantema/inducido químicamente , Femenino , Hepacivirus/genética , Hepatitis C/virología , Humanos , Interferón alfa-2 , Interferón-alfa/uso terapéutico , Masculino , Persona de Mediana Edad , Oligopéptidos/efectos adversos , Polietilenglicoles/uso terapéutico , Proteínas Recombinantes , Ribavirina/uso terapéutico , Adulto Joven
14.
J Pharm Sci ; 113(2): 332-344, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37992868

RESUMEN

One of the key unit operations during the aseptic fill-finish process of parenteral products, such as biologics, is the filling process of the formulated, sterile filtered drug substance into primary packaging containers. The applied filling technology as well as the process performance majorly impacts final drug product quality. The present review provides an overview of commonly used filling technologies during fill-finish operations of biologics including positive displacement pump systems such as radial peristaltic pump, rotary piston pump, rolling diaphragm pump, or innovative systems such as the linear peristaltic pump, as well as time-over-pressure filling technology. The article describes the operating principle of each pump system and reviews advantages and drawbacks. We highlight specific considerations for individual systems, such as the risk of protein particle formation and particle shedding from wear and tear of tubing, and discuss current literature about general challenges associated with the filling process, such as hydrogen peroxide uptake, adsorption phenomena to tubing material, and needle clogging. We suggest process development and process characterization studies to assess the impact of the filling process on product quality, and lastly provide an outlook about the use of disposable equipment during filling operations related to sustainability considerations.


Asunto(s)
Productos Biológicos , Tecnología Farmacéutica , Anticuerpos Monoclonales , Embalaje de Medicamentos , Peróxido de Hidrógeno
16.
Bioorg Med Chem Lett ; 23(24): 6743-6, 2013 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-24252544

RESUMEN

The botulinum neurotoxins, characterized by their neuromuscular paralytic effects, are the most toxic proteins known to man. Due to their extreme potency, ease of production, and duration of activity, the BoNT proteins have been classified by the Centers for Disease Control as high threat agents for bioterrorism. In an attempt to discover effective BoNT therapeutics, we have pursued a strategy in which we leverage the blockade of K(+) channels that ultimately results in the reversal of neuromuscular paralysis. Towards this end, we utilized peptides derived from scorpion venom that are highly potent K(+) channel blockers. Herein, we report the synthesis of charybdotoxin, a 37 amino acid peptide, and detail its activity, along with iberiotoxin and margatoxin, in a mouse phrenic nerve hemidiaphragm assay in the absence and the presence of BoNT/A.


Asunto(s)
Toxinas Botulínicas , Caribdotoxina/química , Parálisis/inducido químicamente , Parálisis/tratamiento farmacológico , Nervio Frénico/efectos de los fármacos , Bloqueadores de los Canales de Potasio/química , Venenos de Escorpión , Secuencia de Aminoácidos , Animales , Caribdotoxina/farmacología , Caribdotoxina/uso terapéutico , Ratones , Datos de Secuencia Molecular , Contracción Muscular/efectos de los fármacos , Péptidos/química , Péptidos/farmacología , Bloqueadores de los Canales de Potasio/farmacología , Bloqueadores de los Canales de Potasio/uso terapéutico , Resinas Sintéticas/química , Venenos de Escorpión/química , Venenos de Escorpión/farmacología , Venenos de Escorpión/uso terapéutico
17.
J Arthroplasty ; 28(7): 1231-4, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23643031

RESUMEN

In recent years, metal-on-metal (MOM) arthroplasty has come under fire with reported adverse outcomes of metal hypersensitivity, adverse local tissue reaction (ALTR), and the carcinogenicity concern from systemic metal ions. We present a retrospective analysis of 354 primary total hip arthroplasties from 2 independent centers. Revision data, predicted survival and Harris Hip Scores (HHS) are reported. Nine hips (2.5%) underwent component revision, and 9 year predicted survival was 95.8%. One revision had elevated metal ions but no histological evidence of ALTR. Average HHS at a minimum 5 year follow up (range 5-10 years) improved significantly from 52 pre-operatively to 93 post-operatively. While a 2.5% revision rate and improved clinical outcomes are reported in this study, longer term follow-up is warranted to monitor for late complications.


Asunto(s)
Artroplastia de Reemplazo de Cadera/instrumentación , Prótesis de Cadera , Metales , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Iones , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Diseño de Prótesis , Falla de Prótesis , Reoperación/estadística & datos numéricos , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento
18.
BMC Genomics ; 13: 363, 2012 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-22853566

RESUMEN

BACKGROUND: Aquaculture of piscivorous fish is in continual expansion resulting in a global requirement to reduce the dependence on wild caught fish for generation of fishmeal and fish oil. Plant proteins represent a suitable protein alternative to fish meal and are increasingly being used in fish feed. In this study, we examined the transcriptional response of Atlantic salmon (Salmo salar) to a high marine protein (MP) or low fishmeal, higher plant protein replacement diet (PP), formulated to the same nutritional specification within previously determined acceptable maximum levels of individual plant feed materials. RESULTS: After 77 days of feeding the fish in both groups doubled in weight, however neither growth performance, feed efficiency, condition factor nor organ indices were significantly different. Assessment of histopathological changes in the heart, intestine or liver did not reveal any negative effects of the PP diet. Transcriptomic analysis was performed in mid intestine, liver and skeletal muscle, using an Atlantic salmon oligonucleotide microarray (Salar_2, Agilent 4x44K). The dietary comparison revealed large alteration in gene expression in all the tissues studied between fish on the two diets. Gene ontology analysis showed, in the mid intestine of fish fed PP, higher expression of genes involved in enteritis, protein and energy metabolism, mitochondrial activity/kinases and transport, and a lower expression of genes involved in cell proliferation and apoptosis compared to fish fed MP. The liver of fish fed PP showed a lower expression of immune response genes but a higher expression of cell proliferation and apoptosis processes that may lead to cell reorganization in this tissue. The skeletal muscle of fish fed PP vs MP was characterized by a suppression of processes including immune response, energy and protein metabolism, cell proliferation and apoptosis which may reflect a more energy efficient tissue. CONCLUSIONS: The PP diet resulted in significant effects on transcription in all the 3 tissues studied. Despite of these alterations, we demonstrated that high level of plant derived proteins in a salmon diet allowed fish to grow with equal efficiency as those on a high marine protein diet, and with no difference in biometric quality parameters.


Asunto(s)
Alimentación Animal , Metabolismo Energético/inmunología , Proteínas de Peces/metabolismo , Proteínas de Plantas/metabolismo , Salmo salar/genética , Transcriptoma , Animales , Peso Corporal , Dieta , Metabolismo Energético/genética , Explotaciones Pesqueras , Perfilación de la Expresión Génica , Mucosa Intestinal/metabolismo , Hígado/metabolismo , Músculo Esquelético/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Salmo salar/metabolismo , Reino Unido
19.
Am J Perinatol ; 29(6): 455-8, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22399217

RESUMEN

OBJECTIVE: To compare the bactericidal properties of povidone-iodine versus alcohol-based chlorhexidine solution for cleansing the gravid abdomen prior to amniocentesis. METHODS: Fifty study participants were recruited from the University of Texas Women's Clinic in Houston, Texas. Two baseline swabs of the patients' abdomens were obtained to assess bacterial flora prior to treatment. A 10% povidone-iodine solution and 2% chlorhexidine gluconate with 70% isopropyl alcohol solution in a 3-mL prefilled applicator (Chloraprep, Cardinal Health, Inc., Leawood, KS) were then applied on different sides of the abdomen. After 30 seconds, cultures were obtained and plated on Trypticase Soy (PML Microbiologicals, Durham, NC) with sheep's blood agar for aerobic flora. Plates were incubated at 37°C for 48 hours for aerobic flora. Colony-forming units were counted and recorded. RESULTS: No statistically significant difference was detected between baseline colony counts between the left and right side of each patient's abdomen (p = 0.33) prior to cleansing. Postcleansing colony counts were evaluated, and a statistically significant difference was identified, favoring chlorhexidine as a more efficacious abdominal cleanser (p <0.001). CONCLUSION: We demonstrated that 2% chlorhexidine with 70% isopropyl alcohol had excellent bactericidal efficacy and was superior to povidone-iodine for cleansing the maternal abdomen.


Asunto(s)
Amniocentesis/métodos , Antibacterianos/farmacología , Antiinfecciosos Locales/farmacología , Clorhexidina/farmacología , Povidona Yodada/farmacología , Adulto , Femenino , Humanos , Embarazo , Piel/microbiología
20.
J Arthroplasty ; 27(7): 1408-12, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22197289

RESUMEN

Pelvic dissociation is a rare but serious potential complication of total hip arthroplasty. The purpose of this study is to evaluate the effectiveness of the false profile view compared with traditional radiographs in detecting pelvic dissociation. Ten cadaver pelves were skeletonized, and noncemented acetabular hip arthroplasty components were implanted. Anteroposterior, lateral, iliac oblique, and false profile radiographs were obtained before and after creating pelvic dissociations and analyzed in a blinded fashion. The sensitivity of the false profile view for detecting pelvic dissociation was 79% (confidence interval, 70-86), which was greater than the sensitivity for anteroposterior and lateral views. This difference was statistically significant. False profile views are a potentially valuable addition to the traditional radiographic evaluation of pelvic discontinuity in hip arthroplasty.


Asunto(s)
Acetábulo/diagnóstico por imagen , Artroplastia de Reemplazo de Cadera/efectos adversos , Prótesis de Cadera/efectos adversos , Huesos Pélvicos/diagnóstico por imagen , Complicaciones Posoperatorias/diagnóstico por imagen , Radiografía/métodos , Resorción Ósea/complicaciones , Cadáver , Humanos , Modelos Anatómicos , Fracturas Periprotésicas/complicaciones , Sensibilidad y Especificidad
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