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1.
PLoS One ; 18(7): e0288598, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37450478

RESUMEN

OBJECTIVES: Maraviroc may reduce hepatic inflammation in people with HIV and non-alcoholic fatty liver disease (HIV-NAFLD) through CCR5-receptor antagonism, which warrants further exploration. METHODS: We performed an open-label 96-week randomised-controlled feasibility trial of maraviroc plus optimised background therapy (OBT) versus OBT alone, in a 1:1 ratio, for people with virologically-suppressed HIV-1 and NAFLD without cirrhosis. Dosing followed recommendations for HIV therapy in the Summary of Product Characteristics for maraviroc. The primary outcomes were safety, recruitment and retention rates, adherence and data completeness. Secondary outcomes included the change in Fibroscan-assessed liver stiffness measurements (LSM), controlled attenuation parameter (CAP) and Enhanced Liver Fibrosis (ELF) scores. RESULTS: Fifty-three participants (53/60, 88% of target) were recruited; 23 received maraviroc plus OBT; 89% were male; 19% had type 2 diabetes mellitus. The median baseline LSM, CAP & ELF scores were 6.2 (IQR 4.6-7.8) kPa, 325 (IQR 279-351) dB/m and 9.1 (IQR 8.6-9.6) respectively. Primary outcomes: all individuals eligible after screening were randomised; there was 92% (SD 6.6%) adherence to maraviroc [target >90%]; 83% (95%CI 70%-92%) participant retention [target >65%]; 5.5% of data were missing [target <20%]. There were noo Serious Adverse Reactions; mild-moderate intensity Adverse Reactions were reported by five participants (5/23, 22% (95%CI 5%-49%)) [target <10%]. All Adverse Reactions resolved. Secondary outcomes: no important differences were seen by treatment group for the change from baseline in LSM, CAP or ELF scores. CONCLUSIONS: This feasibility study provides preliminary evidence of maraviroc safety amongst people with HIV-NAFLD, and acceptable recruitment, retention, and adherence rates. These data support a definitive randomised-controlled trial assessing maraviroc impact on hepatic steatosis and fibrosis. TRIAL REGISTRATION: Clinical trial registry: ISCRTN, registration number 31461655.


Asunto(s)
Diabetes Mellitus Tipo 2 , Diagnóstico por Imagen de Elasticidad , Infecciones por VIH , VIH-1 , Enfermedad del Hígado Graso no Alcohólico , Humanos , Masculino , Femenino , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Maraviroc/uso terapéutico , Diabetes Mellitus Tipo 2/complicaciones , Estudios de Factibilidad , Cirrosis Hepática/patología , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/patología , Hígado/patología
2.
Cureus ; 15(5): e38877, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37303421

RESUMEN

Canines historically have been proven to have great benefits in human medicine. They have a unique ability to detect volatile organic compounds, or VOCs, in several different diseases, which allows them to work efficiently as a medical alert dog or detect the presence of certain diseases in human samples. Early studies have shown efficiency in the ability of canines to detect malignant cells from primary lung tumors in the fluid and breath samples of patients. Lung cancer is the third most common cancer and is the number one cause of cancer-related deaths in the United States. Because of its commonality, The U.S. Preventive Services Task Force developed guidelines for screening high-risk individuals, which includes low-dose CT with proven efficacy. Although effective, it comes with limitations, including increased cost, concern for radiation exposure, and low compliance amongst those who are eligible for screening. Other screening methods have been studied to overcome these deficiencies, including the use of canines trained in medical scent detection. Medical scent canines may prove to be an efficient alternative form of screening to the traditional use of low-dose CT and may be a viable non-imaging screening alternative.

3.
J Chem Inf Model ; 62(24): 6292-6296, 2022 12 26.
Artículo en Inglés | MEDLINE | ID: mdl-35213161

RESUMEN

A peer-mentoring network, funded by the National Science Foundation ADVANCE program, profoundly impacted the career trajectory of five women chemistry faculty at predominantly undergraduate institutions. By providing each other support, encouragement, information, and accountability, we advanced our careers, became leaders in our own right, and implemented change at our institutions. To extend this benefit to more women STEM faculty, we have developed and implemented a model to support 74 faculty and administrators representing 51 institutions across the country.


Asunto(s)
Tutoría , Humanos , Femenino , Evaluación de Programas y Proyectos de Salud , Mentores , Grupo Paritario , Docentes
4.
Toxicol Sci ; 176(1): 224-235, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32298455

RESUMEN

Integrating nonclinical in vitro, in silico, and in vivo datasets holistically can improve hazard characterization and risk assessment. In pharmaceutical development, cardiovascular liabilities are a leading cause of compound attrition. Prior to clinical studies, functional cardiovascular data are generated in single-dose safety pharmacology telemetry studies, with structural pathology data obtained from repeat-dose toxicology studies with limited concurrent functional endpoints, eg, electrocardiogram via jacketed telemetry. Relationships between datasets remain largely undetermined. To address this gap, a cross-pharma collaboration collated functional and structural data from 135 compounds. Retrospective functional data were collected from good laboratory practice conscious dog safety pharmacology studies: effects defined as hemodynamic blood pressure or heart rate changes. Morphologic pathology findings (mainly degeneration, vacuolation, inflammation) from related toxicology studies in the dog (3-91 days repeat-dosing) were reviewed, harmonized, and location categorized: cardiac muscle (myocardium, epicardium, endocardium, unspecified), atrioventricular/aortic valves, blood vessels. The prevalence of cardiovascular histopathology changes was 11.1% of compounds, with 53% recording a functional blood pressure or heart rate change. Correlations were assessed using the Mantel-Haenszel Chi-square trend test, identifying statistically significant associations between cardiac muscle pathology and (1) decreased blood pressure, (2) increased heart rate, and between cardiovascular vessel pathology and increased heart rate. Negative predictive values were high, suggesting few compounds cause repeat-dose cardiovascular structural change in the absence of functional effects in single-dose safety pharmacology studies. Therefore, observed functional changes could prompt moving (sub)chronic toxicology studies forward, to identify cardiovascular liabilities earlier in development, and reduce late-stage attrition.


Asunto(s)
Sistema Cardiovascular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Animales , Presión Sanguínea , Perros , Evaluación Preclínica de Medicamentos , Electrocardiografía , Frecuencia Cardíaca , Hemodinámica , Masculino , Estudios Retrospectivos , Telemetría
5.
Ear Hear ; 41(1): 25-38, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31584501

RESUMEN

OBJECTIVES: Permanent threshold elevation after noise exposure, ototoxic drugs, or aging is caused by loss of sensory cells; however, animal studies show that hair cell loss is often preceded by degeneration of synapses between sensory cells and auditory nerve fibers. The silencing of these neurons, especially those with high thresholds and low spontaneous rates, degrades auditory processing and may contribute to difficulties in understanding speech in noise. Although cochlear synaptopathy can be diagnosed in animals by measuring suprathreshold auditory brainstem responses, its diagnosis in humans remains a challenge. In mice, cochlear synaptopathy is also correlated with measures of middle ear muscle (MEM) reflex strength, possibly because the missing high-threshold neurons are important drivers of this reflex. The authors hypothesized that measures of the MEM reflex might be better than other assays of peripheral function in predicting difficulties hearing in difficult listening environments in human subjects. DESIGN: The authors recruited 165 normal-hearing healthy subjects, between 18 and 63 years of age, with no history of ear or hearing problems, no history of neurologic disorders, and unremarkable otoscopic examinations. Word recognition in quiet and in difficult listening situations was measured in four ways: using isolated words from the Northwestern University auditory test number six corpus with either (a) 0 dB signal to noise, (b) 45% time compression with reverberation, or (c) 65% time compression with reverberation, and (d) with a modified version of the QuickSIN. Audiometric thresholds were assessed at standard and extended high frequencies. Outer hair cell function was assessed by distortion product otoacoustic emissions (DPOAEs). Middle ear function and reflexes were assessed using three methods: the acoustic reflex threshold as measured clinically, wideband tympanometry as measured clinically, and a custom wideband method that uses a pair of click probes flanking an ipsilateral noise elicitor. Other aspects of peripheral auditory function were assessed by measuring click-evoked gross potentials, that is, summating potential (SP) and action potential (AP) from ear canal electrodes. RESULTS: After adjusting for age and sex, word recognition scores were uncorrelated with audiometric or DPOAE thresholds, at either standard or extended high frequencies. MEM reflex thresholds were significantly correlated with scores on isolated word recognition, but not with the modified version of the QuickSIN. The highest pairwise correlations were seen using the custom assay. AP measures were correlated with some of the word scores, but not as highly as seen for the MEM custom assay, and only if amplitude was measured from SP peak to AP peak, rather than baseline to AP peak. The highest pairwise correlations with word scores, on all four tests, were seen with the SP/AP ratio, followed closely by SP itself. When all predictor variables were combined in a stepwise multivariate regression, SP/AP dominated models for all four word score outcomes. MEM measures only enhanced the adjusted r values for the 45% time compression test. The only other predictors that enhanced model performance (and only for two outcome measures) were measures of interaural threshold asymmetry. CONCLUSIONS: Results suggest that, among normal-hearing subjects, there is a significant peripheral contribution to diminished hearing performance in difficult listening environments that is not captured by either threshold audiometry or DPOAEs. The significant univariate correlations between word scores and either SP/AP, SP, MEM reflex thresholds, or AP amplitudes (in that order) are consistent with a type of primary neural degeneration. However, interpretation is clouded by uncertainty as to the mix of pre- and postsynaptic contributions to the click-evoked SP. None of the assays presented here has the sensitivity to diagnose neural degeneration on a case-by-case basis; however, these tests may be useful in longitudinal studies to track accumulation of neural degeneration in individual subjects.


Asunto(s)
Potenciales Evocados Auditivos del Tronco Encefálico , Audición , Pruebas de Impedancia Acústica , Animales , Umbral Auditivo , Oído Medio , Ratones , Músculos , Emisiones Otoacústicas Espontáneas , Reflejo Acústico
6.
Inorg Chem ; 57(11): 6309-6323, 2018 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-29791143

RESUMEN

This paper describes the preparation and comprehensive characterization of a series of water-soluble cationic silver(I)-centered complexes featuring the hemilabile P, N-ligand known as 3,7-dimethyl-1,3,5-triaza-7-phosphabicyclo[3.3.1]nonane (herein abbreviated as PTN(Me)) and differing types of monoanionic counterions including known biologically active sulfadiazine and triclosan. The complexes primarily differed though the number of coordinating PTN(Me) ligands. The bis-substituted Ag(I) complexes revealed P, N bidentate coordination, while the only P-monocoordination of the metal center was observed for the tris-substituted systems. The bis-ligated silver compounds were observed to quickly degrade upon photoexposure or in contact with air. In contrast, the tris-ligated complexes demonstrated greater stability, in particular, a high resistance to photo-decomposition. Calculated geometry optimized models using the density functional theory method (BP86) revealed for the bis-substituted PTN(Me) Ag(I) species that the total enthalpy of the tetrahedral C2-symmetric structure is marginally lower by -0.6 kcal mol-1 compared to the planar C2 h structure, which is analogous for the corresponding [Au(PTN(Me))2]+ complex with Δ H = -0.5 kcal mol-1. Hence both types of complexes feature free rotation of the PTN ligand about the M-P bond axis. This series of Ag(I) and bis-PTN(Me) Au(I) complexes were evaluated using the agar well diffusion test for potential antimicrobial and antifungal activity. The nature of the counterion was found to have a strong correlation with the area of microbiological growth inhibition. Silver(I) complexes bearing the deprotonated triclosan as the counterion demonstrated the greatest activity, with large zones of growth inhibition, with the tris-ligated triclosan complex obtaining of a high clearance of 42 mm against the Gram-negative Escherichia coli. In contrast, the previously reported [Au(PTN(Me))2]Cl complex demonstrated activity only against E. coli, which is lower than that observed for the silver(I) PTN(Me) species.


Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Compuestos de Azabiciclo/farmacología , Complejos de Coordinación/farmacología , Compuestos Organofosforados/farmacología , Plata/química , Antibacterianos/síntesis química , Antibacterianos/química , Antifúngicos/síntesis química , Antifúngicos/química , Compuestos de Azabiciclo/síntesis química , Compuestos de Azabiciclo/química , Complejos de Coordinación/síntesis química , Complejos de Coordinación/química , Cristalografía por Rayos X , Estabilidad de Medicamentos , Escherichia coli/efectos de los fármacos , Ligandos , Luz , Pruebas de Sensibilidad Microbiana , Hongos Mitospóricos/efectos de los fármacos , Modelos Químicos , Estructura Molecular , Compuestos Organofosforados/síntesis química , Compuestos Organofosforados/química , Espectroscopía de Protones por Resonancia Magnética , Teoría Cuántica , Solubilidad , Staphylococcus aureus/efectos de los fármacos , Triclosán/farmacología , Agua/química
7.
J Inorg Biochem ; 182: 177-183, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29501978

RESUMEN

The ruthenium-based anticancer agent NAMI-A (ImH[trans-RuCl4(dmso)(Im)], where Im = imidazole) has been shown to interact with RNA in vivo and in vitro. We hypothesized that the similarly structured drug KP1019 (IndH[trans-RuCl4(Ind)2], where Ind = indazole) binds to RNA as well. Fluorescence spectroscopy was employed to assay the interactions between either NAMI-A or KP1019 and tRNAPhe through an intrinsic fluorophore wybutosine (Y) base and by extrinsic displacement of the intercalating agent ethidium bromide. In both the intrinsic Y-base and extrinsic ethidium bromide studies, KP1019 exhibited tighter binding to phenylalanine-specific tRNA (tRNAPhe) than NAMI-A. In the ethidium bromide study, reducing both drugs from RuIII to RuII resulted in a significant decrease in binding. Our findings suggest that the relatively large heteroaromatic indazole ligands of KP1019 intercalate in the π-stacks of tRNAPhe within structurally complex binding pockets. In addition, NAMI-A appears to be sensitive to destabilizing electrostatic interactions with the negative phosphate backbone of tRNAPhe. Interactions with additional tRNA molecules and other types of RNA require further evaluation to determine the role of RNA in the mechanisms of action for KP1019 and to better understand how Ru drugs fundamentally interact with biomolecules that are more structurally sophisticated than short DNA oligonucleotides. To the best of our knowledge, this is the first study to report KP1019 binding interactions with RNA.


Asunto(s)
Antineoplásicos/química , Dimetilsulfóxido/análogos & derivados , Indazoles/química , Compuestos Organometálicos/química , ARN de Transferencia de Fenilalanina/química , Rutenio/química , Dimetilsulfóxido/química , ARN/química , Compuestos de Rutenio
8.
Eur J Cancer ; 89: 27-35, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29223479

RESUMEN

BACKGROUND: We report long-term efficacy and cardiac safety outcomes in patients with HER2-positive early breast cancer treated with neoadjuvant pertuzumab plus trastuzumab with anthracycline-containing or anthracycline-free chemotherapy. METHODS: Descriptive efficacy analyses were conducted in patients randomised to group A (cycles 1-6: trastuzumab [8 mg/kg loading dose and 6 mg/kg maintenance] plus pertuzumab [840 mg loading dose and 420 mg maintenance], plus 5-fluorouracil, epirubicin and cyclophosphamide [FEC] [cycles 1-3; 500 mg/m2 5-fluorouracil/100 mg/m2 epirubicin/600 mg/m2 cyclophosphamide] then docetaxel [cycles 4-6; 75 mg/m2, escalated to 100 mg/m2 if well tolerated]), B (cycles 1-3: FEC, cycles 4-6: trastuzumab plus pertuzumab plus docetaxel as mentioned previously) or C (cycles 1-6: trastuzumab plus pertuzumab plus docetaxel [75 mg/m2, without dose escalation], and carboplatin [AUC 6]), five years after randomisation of the last patient. This study is registered with ClinicalTrials.gov, number NCT00976989. RESULTS: Three-year Kaplan-Meier survival estimates for disease-free survival (DFS) were 87% (95% confidence interval: 79-95), 88% (80-96) and 90% (82-97) in groups A-C, respectively. Progression-free survival (PFS) rates were 89% (81-96), 89% (81-96) and 87% (80-95). DFS hazard ratio for total pathological complete response (tpCR) versus no tpCR was 0.27 (0.11-0.64). During post-treatment follow-up, 2/72 (2.8%), 3/75 (4.0%) and 4/76 (5.4%) patients in groups A-C had any-grade left ventricular systolic dysfunction; eight (11.1%), 12 (16.0%) and nine (11.8%) patients experienced left ventricular ejection fraction declines ≥10% from baseline to <50%. CONCLUSIONS: Long-term DFS and PFS were similar between groups. Patients who achieved tpCR had improved DFS. No new safety signals were identified.


Asunto(s)
Antraciclinas/administración & dosificación , Anticuerpos Monoclonales Humanizados/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Corazón/efectos de los fármacos , Trastuzumab/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Antraciclinas/efectos adversos , Anticuerpos Monoclonales Humanizados/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias de la Mama/mortalidad , Femenino , Humanos , Persona de Mediana Edad , Volumen Sistólico/efectos de los fármacos , Trastuzumab/efectos adversos , Función Ventricular Izquierda/efectos de los fármacos
9.
Breast Cancer Res ; 19(1): 16, 2017 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-28183321

RESUMEN

BACKGROUND: NeoSphere showed significantly higher pathologic complete response (pCR) with neoadjuvant pertuzumab, trastuzumab, and docetaxel compared with trastuzumab plus docetaxel, pertuzumab plus trastuzumab, or pertuzumab plus docetaxel. We assessed associations between human epidermal growth factor receptor 2 (HER2) pathway-related biomarkers and clinical outcome in response to these regimens. METHODS: Tumor, serum, and whole blood samples were collected at baseline and post neoadjuvant treatment before surgery. Associations between biomarkers and pCR, and between biomarkers and clinical variables were assessed in the overall and estrogen receptor (ER)-positive and ER-negative populations. Changes in serum marker levels between baseline and post-neoadjuvant treatment were examined. RESULTS: No markers were associated with pCR across all groups; however, significant associations were observed for two markers in individual groups. High HER2 was significantly associated with higher pCR rates (P = 0.001) and a significant treatment interaction (P = 0.0236) with pertuzumab, trastuzumab, and docetaxel (odds ratio 2.07, P = 0.01). Low serum transforming growth factor alpha (TGFα) was associated with higher pCR rates with pertuzumab plus trastuzumab (P = 0.04) without a significant treatment interaction. Presence of truncated HER2 did not affect pCR. A non-significant decreased pCR benefit was observed consistently across groups in patients with mutated PIK3CA while the treatment benefit from pertuzumab was maintained when comparing the trastuzumab plus docetaxel and pertuzumab, trastuzumab, and docetaxel groups. Notably, PIK3CA exon 9 mutations were associated with residual disease (pooled groups), which was not found for exon 20 mutations. Serum HER2 extracellular domain levels were significantly increased between baseline and post-neoadjuvant treatment in the non-trastuzumab-treated group, and decreased in the trastuzumab-containing groups (likely due to trastuzumab's mechanism of action). Differences in biomarker profiles according to ER status were observed. CONCLUSIONS: The observed associations of HER2 protein levels with sensitivity to pertuzumab, and of PIK3CA exon 9 mutation to lack of sensitivity to HER2-targeted monoclonal antibody treatment, warrant further investigation. Previously reported findings of truncated forms of HER2 as resistance markers to HER2-targeted treatment could not be confirmed in NeoSphere. Conventional HER2 assessment should continue and HER2 remains the only biomarker suitable for patient selection in this population. TRIAL REGISTRATION: Clinicaltrials.gov, NCT00545688 . Registered on 16 October 2007.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Receptor ErbB-2/metabolismo , Anticuerpos Monoclonales Humanizados/administración & dosificación , Biomarcadores de Tumor , Neoplasias de la Mama/genética , Docetaxel , Femenino , Humanos , Inmunohistoquímica , Mutación , Terapia Neoadyuvante , Taxoides/administración & dosificación , Trastuzumab/administración & dosificación , Resultado del Tratamiento
10.
Reprod Toxicol ; 67: 140-145, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-28043866

RESUMEN

The effects on fetal weights and maternal health of taking 32µL blood microsamples at the end of organogenesis in a mouse embryofetal development (EFD) study design was investigated with the aim of reducing satellite animal usage. The effects of warming, handling and sampling either 3 or 6 times on gestation day 16 was evaluated. Maternal body weight gain was transiently reduced when animals underwent warming and handling with or without microsampling. Fetal weights on gestation day 18 were reduced after 6 occasion warming and handling alone or taking samples, but not when sampling was limited to 3 timepoints. Taking 3 microsamples of 32µL had no permanent adverse effects on maternal health or toxicologically significant effects on fetal development (measured by fetal weights). This regimen could be used to generate composite toxicokinetic profiles using only 6 main test animals in mouse EFD studies provided sampling procedures were matched across groups.


Asunto(s)
Alternativas al Uso de Animales , Recolección de Muestras de Sangre/efectos adversos , Desarrollo Embrionario/fisiología , Desarrollo Fetal/fisiología , Proyectos de Investigación , Pruebas de Toxicidad , Animales , Femenino , Manejo Psicológico , Calor , Ratones , Embarazo , Pruebas de Toxicidad/métodos , Pruebas de Toxicidad/normas
11.
Dalton Trans ; 45(35): 13846-52, 2016 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-27513366

RESUMEN

A series of monometallic and bimetallic Al(iii) complexes with substituted naphthyl based Schiff base ligands have been prepared and characterised. When 1-aminonaphthalene based ligands were reacted with AlMe3 monometallic complexes were isolated, however, with 1,5 and 1,8-diaminonaphthalene based ligands bimetallic complexes were formed. In all cases 4-coordinate tetrahedral Al(iii) centres were observed in the solid state and in solution. There was little difference in rate of polymerisation of rac-lactide between the monometallic and bimetallic complexes based on 1,5-diaminonaphthalene. However, for the 1,8-diaminonaphthalene the complex was an order of magnitude faster than the monometallic and the analogous 1,5-system. Moreover, this complex was active at room temperature, which is rare for aluminium initiators, and PLA with a high degree (Pm = 0.82) of isotacticity was observed.


Asunto(s)
Aluminio/química , Complejos de Coordinación/síntesis química , Naftalenos/síntesis química , Poliésteres/síntesis química , Bases de Schiff/química , Complejos de Coordinación/química , Cristalografía por Rayos X , Ligandos , Estructura Molecular , Naftalenos/química , Poliésteres/química , Polimerizacion , Estereoisomerismo , Relación Estructura-Actividad
12.
J Appl Toxicol ; 36(1): 140-50, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25959454

RESUMEN

Potential new drugs are assessed in pre-clinical in vivo studies to determine their safety profiles. The drugs are formulated in vehicles suitable for the route of administration and the physicochemical properties of the drug, aiming to achieve optimal exposure in the test species. The availability of safety data on vehicles is often limited (incomplete data, access restricted/private databases). Nineteen potentially useful vehicles that contained new and/or increased concentrations of excipients and for which little safety data have been published were tested. Vehicles were dosed orally once daily to HanWistar rats for a minimum of 28 days and a wide range of toxicological parameters were assessed. Only 30% (w/v) hydroxypropyl-ß-cyclodextrin was found unsuitable owing to effects on liver enzymes (AST, ALT and GLDH), urinary volume and the kidneys (tubular vacuolation and tubular pigment). 20% (v/v) oleic acid caused increased salivation and hence this vehicle should be used with caution. As 40% (v/v) tetraethylene glycol affected urinary parameters, its use should be carefully considered, particularly for compounds suspected to impact the renal system and studies longer than 1 month. There were no toxicologically significant findings with 10% (v/v) dimethyl sulphoxide, 20% (v/v) propylene glycol, 33% (v/v) Miglyol®812, 20% (w/v) Kolliphor®RH40, 10% (w/v) Poloxamer 407, 5% (w/v) polyvinylpyrrolidone K30 or 10% (v/v) Labrafil®M1944. All other vehicles tested caused isolated or low magnitude effects which would not prevent their use. The aim of sharing these data, including adverse findings, is to provide meaningful information for vehicle selection, thereby avoiding repetition of animal experimentation.


Asunto(s)
Riñón/efectos de los fármacos , Vehículos Farmacéuticos/toxicidad , beta-Ciclodextrinas/toxicidad , 2-Hidroxipropil-beta-Ciclodextrina , Animales , Dimetilsulfóxido/toxicidad , Glicoles de Etileno/toxicidad , Femenino , Riñón/patología , Masculino , Tamaño de los Órganos/efectos de los fármacos , Poloxámero/toxicidad , Propilenglicol/toxicidad , Ratas , Triglicéridos/toxicidad
13.
Biochem Mol Biol Educ ; 43(3): 181-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25726810

RESUMEN

We have developed a multiweek laboratory project in which students isolate myoglobin and characterize its structure, function, and redox state. The important laboratory techniques covered in this project include size-exclusion chromatography, electrophoresis, spectrophotometric titration, and FTIR spectroscopy. Regarding protein structure, students work with computer modeling and visualization of myoglobin and its homologues, after which they spectroscopically characterize its thermal denaturation. Students also study protein function (ligand binding equilibrium) and are instructed on topics in data analysis (calibration curves, nonlinear vs. linear regression). This upper division biochemistry laboratory project is a challenging and rewarding one that not only exposes students to a wide variety of important biochemical laboratory techniques but also ties those techniques together to work with a single readily available and easily characterized protein, myoglobin.


Asunto(s)
Bioquímica/educación , Bioquímica/métodos , Modelos Moleculares , Mioglobina , Humanos , Mioglobina/química , Mioglobina/aislamiento & purificación , Mioglobina/metabolismo , Relación Estructura-Actividad
14.
Regul Toxicol Pharmacol ; 69(3): 425-33, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24852489

RESUMEN

UNLABELLED: Tail vein microsampling in juvenile rats for toxicokinetic assessment has the potential to significantly reduce satellite animal use. This paper explores the toxicological consequences of microsampling at various post natal day (PND) ages. METHODS: Microsamples were taken as follows: suckling pups, 10 pups/sex, 3×32µL samples on PND19, euthanased PND20; weaned pups, 10 pups/sex, 6×32µL samples on PND23 and PND37, euthanased PND38; and satellite pups, 3 pups/sex, 5×32µL samples on PND14 and PND35, euthanased on PND36. At termination on PND20 or PND38, clinical pathology samples were obtained and spleen, liver and bone marrow were examined. There were 10 unsampled concurrent control animals for each experiment. RESULTS: Suckling animals: females showed a slight, statistically significant decrease in red blood cell count (0.94× of control; p<0.05) with slight decreases in haemoglobin and haematocrit. The suckling males showed a slight increase in reticulocyte counts (1.05× of control) plus a statistically significant, slight increase in relative splenic weight. Weanling animals: the only effect was decreased liver weight in the microsampled females. In both suckling and weanling experiments, all clinical pathology values were within the age control range. In the satellite pups microsampled on PND14, there was a statistically significant transient increase in bodyweight gain between PND17 and PND21. CONCLUSION: The nature of the toxicological effects of microsampling was as expected. The magnitude of effects does not preclude microsampling main test pups provided care is taken over study design and blood volume loss.


Asunto(s)
Animales Recién Nacidos/sangre , Animales Recién Nacidos/fisiología , Ingestión de Alimentos/fisiología , Animales , Peso Corporal/efectos de los fármacos , Peso Corporal/fisiología , Médula Ósea/efectos de los fármacos , Médula Ósea/fisiología , Femenino , Hígado/efectos de los fármacos , Hígado/fisiología , Masculino , Patología Clínica/métodos , Ratas , Ratas Sprague-Dawley , Bazo/efectos de los fármacos , Bazo/fisiología , Destete
15.
Regul Toxicol Pharmacol ; 68(3): 325-31, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24434616

RESUMEN

UNLABELLED: Historically, satellite groups are often used for rodent toxicokinetic profiling because of the haematological consequences of blood sampling. If microsampling is shown to be toxicologically benign, its adoption in rat studies would enable comparison of exposure and toxicity in individual animals (as happens in non-rodent studies) as well as obviating need for satellite groups. METHODS: Groups of 10 male (200-300g) and female (150-250g) rats aged 10weeks were vehicle dosed and either left unsampled, conventional blood volume sampled (6×200µL) or microsampled (6×32µL) on Days 1 and 14. At termination on Day 15, clinical pathology plus liver and spleen weights and histopathology were obtained. RESULTS: All clinical pathology parameters were within background range. However, compared to unsampled controls, conventional volume sampled rats showed a statistically significant (p<0.001) decrease in haemaglobin, haematocrit and red blood cell count, an increase in reticulocytes (at least p<0.01), increased AST and GLDH and, in males only, an increase in monocytes and neutrophils. In contrast, microsampled animals showed no changes except for a slight, toxicologically insignificant decrease in haemoglobin concentration (15.0g/dL compared to the unsampled group mean of 14.4g/dL) in females (p<0.05) and a small increase in monocytes (p<0.05) in males. CONCLUSION: Microsampling of adult rats is possible without adverse toxicological consequences.


Asunto(s)
Recolección de Muestras de Sangre/métodos , Evaluación Preclínica de Medicamentos/métodos , Pruebas de Toxicidad/métodos , Animales , Temperatura Corporal , Femenino , Pruebas Hematológicas , Hígado/anatomía & histología , Masculino , Farmacocinética , Ratas , Ratas Wistar , Restricción Física , Bazo/anatomía & histología
16.
Artículo en Inglés | MEDLINE | ID: mdl-23349064

RESUMEN

BACKGROUND: Inhibin B was measured in plasma samples obtained from 34 healthy male subjects selected on criteria typical for a phase I clinical trial across a wide age range (19-70 years). METHODS: Mutiple samples (up to seven per subject) were obtained as a set consisting of one baseline sample then three pairs of morning and evening samples. This allowed assessment of the fed/fasted state and diurnal effects. Samples were analyzed using a commercially available inhibin B ELISA assay. Across all time points, the mean plasma inhibin B was 197 pg/ml ± 67pg/ml. RESULTS: The results confirmed a diurnal effect where inhibin B concentration is on average about 40 pg/ml greater in the morning and showed a negative influence of age on inhibin B concentrations. There was no overt influence of body mass index on inhibin B. A variance components analysis revealed that more than 80% of the total variability was due to the variability observed between individuals. Within the fed-fasted sampling schedule of this study, inhibin B levels were slightly lower when volunteers had eaten but the magnitude of this effect was within the variance encountered between occasions. CONCLUSION: These results illustrate that when undertaking longitudinal monitoring of inhibin B in clinical trials as means of monitoring testicular function, it is important to obtain samples from an individual at the same time of day and to use statistical methods which analyze the magnitude of deviation of an individual from their personal baseline as well as looking at group means and influence of study duration.


Asunto(s)
Fertilidad , Salud , Inhibinas/sangre , Adolescente , Adulto , Anciano , Envejecimiento/sangre , Índice de Masa Corporal , Ritmo Circadiano/fisiología , Ayuno/sangre , Conducta Alimentaria , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
17.
J Community Health ; 37(6): 1296-300, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22648657

RESUMEN

Parents of children who attend Head Start Centers are key participants in the health promotion and care of their own children. This non-randomized, longitudinal study aimed to test the effectiveness of an educational intervention based on the asthma and healthy homes curriculum targeting parents of Head Start children with or without an asthma diagnosis. One hundred and fifteen parents of children in Head Start Centers received an educational intervention at their corresponding sites, additionally pre- and post-test surveys were administered to measure educational intervention outcomes. A follow-up survey was conducted 6 months after the educational intervention was offered. Results showed a statistically significant increase in asthma and healthy home-knowledge (p < 0.001) in several areas. At 6 months post-intervention (54.4 %) (61 participants) were contacted and 98.4 % of made changes in their households as a result of their training. This study suggests that education can improve knowledge and change behaviors for the well-being of the residents of that household.


Asunto(s)
Asma/prevención & control , Educación en Salud , Conocimientos, Actitudes y Práctica en Salud , Promoción de la Salud/métodos , Padres/educación , Asma/diagnóstico , Guarderías Infantiles , Preescolar , Curriculum , Evaluación Educacional , Femenino , Estudios de Seguimiento , Vivienda , Humanos , Masculino , Padres/psicología , Texas
18.
Toxicol Appl Pharmacol ; 263(2): 171-83, 2012 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-22714037

RESUMEN

Despite rigorous preclinical and clinical safety evaluation, adverse cardiac effects remain a leading cause of drug attrition and post-approval drug withdrawal. A number of cardiovascular screens exist within preclinical development. These screens do not, however, provide a thorough cardiac liability profile and, in many cases, are not preventing the progression of high risk compounds. We evaluated the suitability of the anaesthetised guinea-pig for the assessment of drug-induced changes in cardiovascular parameters. Sodium pentobarbitone anaesthetised male guinea-pigs received three 15 minute intravenous infusions of ascending doses of amoxicillin, atenolol, clonidine, dobutamine, dofetilide, flecainide, isoprenaline, levosimendan, milrinone, moxifloxacin, nifedipine, paracetamol, verapamil or vehicle, followed by a 30 minute washout. Dose levels were targeted to cover clinical exposure and above, with plasma samples obtained to evaluate effect/exposure relationships. Arterial blood pressure, heart rate, contractility function (left ventricular dP/dt(max) and QA interval) and lead II electrocardiogram were recorded throughout. In general, the expected reference compound induced effects on haemodynamic, contractility and electrocardiographic parameters were detected confirming that all three endpoints can be measured accurately and simultaneously in one small animal. Plasma exposures obtained were within, or close to the expected clinical range of therapeutic plasma levels. Concentration-effect curves were produced which allowed a more complete understanding of the margins for effects at different plasma exposures. This single in vivo screen provides a significant amount of information pertaining to the cardiovascular risk of drug candidates, ultimately strengthening strategies addressing cardiovascular-mediated compound attrition and drug withdrawal.


Asunto(s)
Sistema Cardiovascular/efectos de los fármacos , Evaluación Preclínica de Medicamentos/métodos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Modelos Animales , Anestesia/métodos , Animales , Presión Sanguínea/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Electrocardiografía , Cobayas , Frecuencia Cardíaca/efectos de los fármacos , Infusiones Intravenosas , Masculino , Contracción Miocárdica/efectos de los fármacos , Preparaciones Farmacéuticas/administración & dosificación , Fenobarbital/farmacología , Función Ventricular Izquierda/efectos de los fármacos
19.
Toxicol Pathol ; 40(6): 926-30, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22585942

RESUMEN

Wistar rats are frequently selected for use in carcinogenicity studies because of their advantageous survival rate, which is more favorable than other strains such as the Sprague-Dawley (SD) strain. Uterine and mammary tumors are relatively common spontaneous neoplasms of both strains. We examined the incidence and coincidence of uterine tumors and mammary tumors in control animals of both strains within the RITA database. There was a strong inverse relationship between these tumor types in Wistar rats (p < .001). A less strong relationship was present in SD rats (p = .057). This association is likely to be related to prolactin. A short review of the role of prolactin in rats is given. These results are also discussed in the background of nonspecific toxicity at high dose levels in carcinogenicity studies above MTD levels resulting in reduction in body weights of >10%.


Asunto(s)
Neoplasias Mamarias Animales/epidemiología , Prolactina/metabolismo , Ratas Sprague-Dawley , Ratas Wistar , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/veterinaria , Animales , Femenino , Incidencia , Neoplasias Mamarias Animales/metabolismo , Ratas , Neoplasias del Cuello Uterino/metabolismo
20.
Mutat Res ; 726(1): 36-41, 2011 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-21889997

RESUMEN

A semi-automated scoring system has been developed to provide rapid, accurate assessment of micronuclei in preparations of mononuclear mouse lymphoma L5178Y cells. Following exposure to a range of test agents, flat, single-cell preparations were produced from exponentially growing cultures by cytocentrifugation. Following staining with 4'-6-diamidino-2-phenylindole (DAPI), cells were scanned by use of the MicroNuc module of Metafer 4 v 3.4.102, after modifying the classifier developed for selecting micronuclei in binucleate cells to increase its sensitivity. The image gallery of all cells was then sorted to bring aberrant cells to the top of the gallery to assess visually the numbers of cells with micronuclei, as distinct from other debris. Slide quality was shown to be paramount in obtaining accurate results from an automated scan and the data obtained compared very well with the incidence of micronuclei scored conventionally by microscopy. Compared with manual scoring the time saving is considerable, as more than 2000 images are captured in approximately 2min, with subsequent visual assessment of aberrant cells in the image gallery taking about 1-2min/slide. By scanning all aberrant cells, the system also captures additional information on necrotic, apoptotic and fragmented cells. Although optimised for mouse lymphoma cells, it should be simple to adapt the method for any cell type growing in suspension.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Pruebas de Micronúcleos/métodos , Animales , Leucemia L5178 , Ratones , Micronúcleos con Defecto Cromosómico , Mutágenos/toxicidad , Sensibilidad y Especificidad
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