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1.
Gen Comp Endocrinol ; 341: 114310, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37244410

RESUMEN

The alligator snapping turtle (Macrochelys temminckii) is a species for which captive propagation and reintroduction programs are well established; however, little is known about its reproductive behavior and physiology. In this study, we measured monthly plasma sex steroid hormone concentrations of androgen (T + DHT) estradiol-17B (E2), and progesterone (P4), and used ultrasonography to monitor annual reproductive cycles of a captive population of alligator snapping turtles that is maintained under semi-natural conditions in southeastern Oklahoma. Concurrently, we used automated radio telemetry to measure the relative activity levels of male and female alligator snapping turtles and examine these activity patterns in the context of their reproductive cycles. We also measured monthly concentrations of the glucocorticoid (GC) corticosterone (CORT). Seasonal variation was only detected for T in males, but was observed for T, E2, and P4 in females. Vitellogenesis began in August and ended in April and coincided with elevated E2. Ovulation took place 10-29 April and the nesting period lasted from 11 May - 3 June. Males exhibited greater relative activity levels than females in the fall, winter, and early spring, which coincided with the period when mature sperm would be available for mating. Females were more active than males during the peri-nesting period in the spring. Seasonal changes in CORT were detected and did not differ between males and females. CORT concentrations were elevated in the late spring and summer, coincident with the foraging season, and depressed in the fall, and winter, and at their nadir in the early spring.


Asunto(s)
Caimanes y Cocodrilos , Tortugas , Animales , Masculino , Femenino , Semen , Hormonas Esteroides Gonadales , Progesterona , Corticosterona , Reproducción/fisiología , Estaciones del Año
3.
Adv Exp Med Biol ; 1269: 335-339, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33966239

RESUMEN

Pressure injuries (PIs) are wounds resulting from prolonged pressure exerting on the skin and underlying tissues over bony prominences (e.g., lower back, heels, shoulders) in bed-bound patients and wheelchair users. Minimizing pressure has long been considered the most effective preventative method, and current guidelines require visual skin inspection and repositioning every two hours. However, these strategies are often applied deficiently and do not adequately prevent PIs from becoming penetrating wounds. Recent studies attribute the development of PIs to cell deformation, inflammatory, and ischemic damages that cumulatively propagate from the microscale (death of few cells) to the macroscale (tissue necrosis) within one to several hours. Although the nature of the PI pathogenesis is complex and multifactorial, measuring tissue alterations in real-time may elucidate the origination mechanism and ultimately allow detecting PIs at the earliest stage. In this pilot study, we evaluated the ability of diffuse optical imaging (DOI) to assess hemodynamic changes resulting from prolonged pressure on the sacral tissues in five healthy volunteers laying immobile in a supine position for 2 hours. A thin, body-conforming optical imaging probe encompassing 256 optodes arranged in a regularly spaced grid over a 160 × 160 mm area was used to construct DOI volumetric images representing changes of oxyhemoglobin (HbO2) and deoxyhemoglobin (HHb) concentration from a zeroed baseline. After 2 hours of continuous body weight pressure, hemodynamic images in all subjects were substantially dissimilar from their individual baseline. We also found that hemodynamic similarity computed pairwise across subjects exhibited a high value and limited variability around the mean, thus denoting a consistent level of image similarity across subjects. These preliminary results indicate that prolonged pressure causes distinctive hemodynamic patterns that can be effectively investigated with DOI and that monitoring functional changes over time holds potential for clarifying the development mechanisms of PIs.


Asunto(s)
Oxihemoglobinas , Piel , Voluntarios Sanos , Hemodinámica , Humanos , Proyectos Piloto
4.
Clin Neurophysiol ; 131(12): 2817-2825, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33137572

RESUMEN

OBJECTIVE: Postictal generalized electroencephalographic suppression (PGES) is a pattern of low-voltage scalp electroencephalographic (EEG) activity following termination of generalized seizures. PGES has been associated with both sudden unexplained death in patients with epilepsy and therapeutic efficacy of electroconvulsive therapy (ECT). Automated detection of PGES epochs may aid in reliable quantification of this phenomenon. METHODS: We developed a voltage-based algorithm for detecting PGES. This algorithm applies existing criteria to simulate expert epileptologist readings. Validation relied on postictal EEG recording from patients undergoing ECT (NCT02761330), assessing concordance among the algorithm and four clinical epileptologists. RESULTS: We observed low-to-moderate concordance among epileptologist ratings of PGES. Despite this, the algorithm displayed high discriminability in comparison to individual epileptologists (C-statistic range: 0.86-0.92). The algorithm displayed high discrimination (C-statistic: 0.91) and substantial peak agreement (Cohen's Kappa: 0.65) in comparison to a consensus of clinical ratings. Interrater agreement between the algorithm and individual epileptologists was on par with that among expert epileptologists. CONCLUSIONS: An automated voltage-based algorithm can be used to detect PGES following ECT, with discriminability nearing that of experts. SIGNIFICANCE: Algorithmic detection may support clinical readings of PGES and improve precision when correlating this marker with clinical outcomes following generalized seizures.


Asunto(s)
Algoritmos , Electroencefalografía/normas , Epilepsia/epidemiología , Epilepsia/fisiopatología , Muerte Súbita e Inesperada en la Epilepsia/epidemiología , Electroencefalografía/métodos , Epilepsia/diagnóstico , Humanos , Reproducibilidad de los Resultados , Muerte Súbita e Inesperada en la Epilepsia/prevención & control
5.
Epilepsy Curr ; 20(5): 312-315, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32833573

RESUMEN

There are an increasing number of clinical studies for COVID-19, with several large cohort studies documenting initial signs and symptoms. Realizing the need for current information, this summary provides a focused summary of pertinent clinical diagnostic information about neurological involvement of SARS-CoV-2 virus and clinical presentation of COVID-19, especially in relationship to patients with seizures and epilepsy. There is no evidence from cohort studies in the general population that seizures are worsened in COVID-19. However, relative lack of cohort studies in patients with a history of epileptic seizures limit conclusions about effects of COVID-19 patients with epilepsy. Overall, findings indicate seizures and epilepsy are rare, especially in mild COVID-19 cases, but may occur in more severe cases later in the disease course. Caregivers should be vigilant in assessing for possible seizures, especially in patients with systemic effects of severe COVID-19 infections.

6.
Langmuir ; 36(19): 5428-5434, 2020 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-32336098

RESUMEN

Short sequences of DNA immobilized on gold surfaces can be used to capture an array of target molecules because of their high level of specificity. Depending on the nature of the target molecules, the proper density and distribution of the immobilized DNA molecules are fundamental to the quality of the sensor. With the aim to control the packing density and minimize the heterogeneity of the surfaces, DNA-dendron conjugate molecules were synthesized in solution and used to make self-assembled monolayers of single-stranded DNA surfaces on gold. The headgroups used were polyamido amine dendrons (cleaved cystamine core dendrimers) of generations two through five. The structural composition of these self-assembled monolayers was characterized using grazing angle Fourier-transform infrared and X-ray photoelectron spectroscopies. Surface plasmon resonance was used to measure surface densities of the probe monolayers and each monolayer's ability to capture fully complementary DNA strands from solution. The surface density of the probe monolayers was found to decrease with increasing dendron generation number, while the hybridization efficiency increased with increasing dendron generation number.

7.
Mol Neurobiol ; 56(6): 4566-4581, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30353492

RESUMEN

The role of astrocytes is becoming increasingly important to understanding how glioblastoma (GBM) tumor cells diffusely invade the brain. Yet, little is known of the contribution of extracellular vesicle (EV) signaling in GBM/astrocyte interactions. We modeled GBM-EV signaling to normal astrocytes in vitro to assess whether this mode of intercellular communication could support GBM progression. EVs were isolated and characterized from three patient-derived GBM stem cells (NES+/CD133+) and their differentiated (diff) progeny cells (NES-/CD133-). Uptake of GBM-EVs by normal primary astrocytes was confirmed by fluorescence microscopy, and changes in astrocyte podosome formation and gelatin degradation were measured. Quantitative mass spectrometry-based proteomics was performed on GBM-EV stimulated astrocytes. Interaction networks were generated from common, differentially abundant proteins using Ingenuity® (Qiagen Bioinformatics) and predicted upstream regulators were tested by qPCR assays. Podosome formation and Cy3-gelatin degradation were induced in astrocytes following 24-h exposure to GBM-stem and -diff EVs, with EVs released by GBM-stem cells eliciting a greater effect. More than 1700 proteins were quantified, and bioinformatics predicted activations of MYC, NFE2L2, FN1, and TGFß1 and inhibition of TP53 in GBM-EV stimulated astrocytes that were then confirmed by qPCR. Further qPCR studies identified significantly decreased Δ133p53 and increased p53ß in astrocytes exposed to GBM-EVs that might indicate the acquisition of a pro-inflammatory, tumor-promoting senescence-associated secretory phenotype (SASP). Inhibition of TP53 and activation of MYC signaling pathways in normal astrocytes exposed to GBM-EVs may be a mechanism by which GBM manipulates astrocytes to acquire a phenotype that promotes tumor progression.


Asunto(s)
Astrocitos/metabolismo , Neoplasias Encefálicas/metabolismo , Vesículas Extracelulares/metabolismo , Glioblastoma/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Transducción de Señal , Proteína p53 Supresora de Tumor/metabolismo , Anciano , Diferenciación Celular , Línea Celular Tumoral , Senescencia Celular , Vesículas Extracelulares/ultraestructura , Gelatina/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Nanopartículas/ultraestructura , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Tamaño de la Partícula , Fenotipo , Podosomas/metabolismo , Isoformas de Proteínas/metabolismo , Proteolisis , Proteoma/metabolismo
8.
PLoS One ; 12(8): e0184101, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28850601

RESUMEN

Wildlife populations often exhibit unequal catchability between subgroups such as males and females. This heterogeneity of capture probabilities can bias both population size and sex ratio estimates. Several authors have suggested that this problem can be overcome by treating males and females as separate populations and calculating a population estimate for each of them. However, this suggestion has received little testing, and many researchers do not implement it. Therefore, we used two simulations to test the utility of this method. One simulated a closed population, while the other simulated an open population and used the robust design to calculate population sizes. We tested both simulations with multiple levels of heterogeneity, and we used a third simulation to test several methods for detecting heterogeneity of capture probabilities. We found that treating males and females as separate populations produced more accurate population and sex ratio estimates. The benefits of this method were particularly pronounced for sex ratio estimates. When males and females were included as a single population, the sex ratio estimates became inaccurate when even slight heterogeneity was present, but when males and females were treated separately, the estimates were accurate even when large biases were present. Nevertheless, treating males and females separately reduced precision, and this method may not be appropriate when capture and recapture rates are low. None of the methods for detecting heterogeneity were robust, and we do not recommend that researchers rely on them. Rather, we suggest separating populations by sex, age, or other subgroups whenever sample sizes permit.


Asunto(s)
Distribución Animal/fisiología , Animales Salvajes , Recolección de Datos/métodos , Razón de Masculinidad , Animales , Simulación por Computador , Femenino , Masculino , Modelos Teóricos , Densidad de Población , Tamaño de la Muestra
9.
Langmuir ; 33(30): 7389-7392, 2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28679055

RESUMEN

DNA nanostructures (DN) are powerful platforms for the programmable assembly of nanomaterials. As applications for DN both as a structural material and as a support for functional biomolecular sensing systems develop, methods enabling the determination of reaction kinetics in real time become increasingly important. In this report, we present a study of the kinetics of streptavidin binding onto biotinylated DN constructs enabled by these planar structures. High-speed AFM was employed at a 2.5 frame/s rate to evaluate the kinetics and indicates that the binding fully saturates in less than 60 s. When the the data was fitted with an adsorption-limited kinetic model, a forward rate constant of 5.03 × 105 s-1 was found.

10.
Oncogenesis ; 6(5): e336, 2017 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-28504693

RESUMEN

High-grade glioma (HGG) is an incurable brain cancer. The transcriptomes of cells within HGG tumors are highly heterogeneous. This renders the tumors unresponsive or able to adapt to therapeutics targeted at single pathways, thereby causing treatment failure. To overcome this, we focused on cyclin-dependent kinase 7 (CDK7), a ubiquitously expressed molecule involved in two major drivers of HGG pathogenesis: cell cycle progression and RNA polymerase-II-based transcription. We tested the activity of THZ1, an irreversible CDK7 inhibitor, on patient-derived primary HGG cell lines and ex vivo HGG patient tissue slices, using proliferation assays, microarray analysis, high-resolution respirometry, cell cycle analysis and in vivo tumor orthografts. The cellular processes affected by CDK7 inhibition were analyzed by reverse transcriptase-quantitative PCR, western blot, flow cytometry and immunofluorescence. THZ1 perturbed the transcriptome and disabled CDK activation, leading to cell cycle arrest at G2 and DNA damage. THZ1 halted transcription of the nuclear-encoded mitochondrial ribosomal genes, reducing mitochondrial translation and oxidative respiration. It also inhibited the expression of receptor tyrosine kinases such as epidermal growth factor receptor (EGFR) and platelet-derived growth factor receptor-α (PDGFR-α), reducing signaling flux through the AKT, extracellular-signal-regulated kinase 1/2 (ERK1/2) and signal transducer and activator of transcription 3 (STAT3) downstream pathways. Finally, THZ1 disrupted nucleolar, Cajal body and nuclear speckle formation, resulting in reduced cytosolic translation and malfunction of the spliceosome and thus leading to aberrant mRNA processing. These findings indicate that CDK7 is crucial for gliomagenesis, validate CDK7 as a therapeutic target and provide new insight into the cellular processes that are affected by THZ1 and induce antitumor activity.

11.
Conserv Biol ; 31(2): 427-436, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27488734

RESUMEN

Survival and reproduction are the two primary life-history traits essential for species' persistence; however, the environmental conditions that support each of these traits may not be the same. Despite this, reproductive requirements are seldom considered when estimating species' potential distributions. We sought to examine potentially limiting environmental factors influencing the distribution of an oviparous reptile of conservation concern with respect to the species' survival and reproduction and to assess the implications of the species' predicted climatic constraints on current conservation practices. We used ecological niche modeling to predict the probability of environmental suitability for the alligator snapping turtle (Macrochelys temminckii). We built an annual climate model to examine survival and a nesting climate model to examine reproduction. We combined incubation temperature requirements, products of modeled soil temperature data, and our estimated distributions to determine whether embryonic development constrained the northern distribution of the species. Low annual precipitation constrained the western distribution of alligator snapping turtles, whereas the northern distribution was constrained by thermal requirements during embryonic development. Only a portion of the geographic range predicted to have a high probability of suitability for alligator snapping turtle survival was estimated to be capable of supporting successful embryonic development. Historic occurrence records suggest adult alligator snapping turtles can survive in regions with colder climes than those associated with consistent and successful production of offspring. Estimated egg-incubation requirements indicated that current reintroductions at the northern edge of the species' range are within reproductively viable environmental conditions. Our results highlight the importance of considering survival and reproduction when estimating species' ecological niches, implicating conservation plans, and benefits of incorporating physiological data when evaluating species' distributions.


Asunto(s)
Conservación de los Recursos Naturales , Estadios del Ciclo de Vida , Tortugas , Animales , Ecología , Temperatura
12.
Br J Cancer ; 114(2): 188-98, 2016 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-26657652

RESUMEN

BACKGROUND: Resistance to temozolomide (TMZ) greatly limits chemotherapeutic effectiveness in glioblastoma (GBM). Here we analysed the ability of the Inhibitor-of-apoptosis-protein (IAP) antagonist birinapant to enhance treatment responses to TMZ in both commercially available and patient-derived GBM cells. METHODS: Responses to TMZ and birinapant were analysed in a panel of commercial and patient-derived GBM cell lines using colorimetric viability assays, flow cytometry, morphological analysis and protein expression profiling of pro- and antiapoptotic proteins. Responses in vivo were analysed in an orthotopic xenograft GBM model. RESULTS: Single-agent treatment experiments categorised GBM cells into TMZ-sensitive cells, birinapant-sensitive cells, and cells that were insensitive to either treatment. Combination treatment allowed sensitisation to therapy in only a subset of resistant GBM cells. Cell death analysis identified three principal response patterns: Type A cells that readily activated caspase-8 and cell death in response to TMZ while addition of birinapant further sensitised the cells to TMZ-induced cell death; Type B cells that readily activated caspase-8 and cell death in response to birinapant but did not show further sensitisation with TMZ; and Type C cells that showed no significant cell death or moderately enhanced cell death in the combined treatment paradigm. Furthermore, in vivo, a Type C patient-derived cell line that was TMZ-insensitive in vitro and showed a strong sensitivity to TMZ and TMZ plus birinapant treatments. CONCLUSIONS: Our results demonstrate remarkable differences in responses of patient-derived GBM cells to birinapant single and combination treatments, and suggest that therapeutic responses in vivo may be greatly affected by the tumour microenvironment.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Apoptosis/efectos de los fármacos , Neoplasias Encefálicas/patología , Dacarbazina/análogos & derivados , Dipéptidos/farmacología , Glioblastoma/patología , Indoles/farmacología , Proteínas Inhibidoras de la Apoptosis/antagonistas & inhibidores , Animales , Western Blotting , Caspasa 8/efectos de los fármacos , Caspasa 8/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Dacarbazina/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Citometría de Flujo , Humanos , Técnicas In Vitro , Ratones , Ratones Endogámicos NOD , Ratones SCID , Microscopía de Contraste de Fase , Trasplante de Neoplasias , Temozolomida , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Cell Death Dis ; 6: e1966, 2015 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-26539913

RESUMEN

Cyclopentenone prostaglandins (CyPGs), such as 15-deoxy-Δ(12,14)-prostaglandin J2 (15dPGJ2), are reactive prostaglandin metabolites exerting a variety of biological effects. CyPGs are produced in ischemic brain and disrupt the ubiquitin-proteasome system (UPS). Ubiquitin-C-terminal hydrolase L1 (UCH-L1) is a brain-specific deubiquitinating enzyme that has been linked to neurodegenerative diseases. Using tandem mass spectrometry (MS) analyses, we found that the C152 site of UCH-L1 is adducted by CyPGs. Mutation of C152 to alanine (C152A) inhibited CyPG modification and conserved recombinant UCH-L1 protein hydrolase activity after 15dPGJ2 treatment. A knock-in (KI) mouse expressing the UCH-L1 C152A mutation was constructed with the bacterial artificial chromosome (BAC) technique. Brain expression and distribution of UCH-L1 in the KI mouse was similar to that of wild type (WT) as determined by western blotting. Primary cortical neurons derived from KI mice were resistant to 15dPGJ2 cytotoxicity compared with neurons from WT mice as detected by the WST-1 cell viability assay and caspase-3 and poly ADP ribose polymerase (PARP) cleavage. This protective effect was accompanied with significantly less ubiquitinated protein accumulation and aggregation as well as less UCH-L1 aggregation in C152A KI primary neurons after 15dPGJ2 treatment. Additionally, 15dPGJ2-induced axonal injury was also significantly attenuated in KI neurons as compared with WT. Taken together, these studies indicate that UCH-L1 function is important in hypoxic neuronal death, and the C152 site of UCH-L1 has a significant role in neuronal survival after hypoxic/ischemic injury.


Asunto(s)
Isquemia Encefálica/genética , Ciclopentanos/toxicidad , Neuronas/efectos de los fármacos , Neuronas/fisiología , Mutación Puntual , Prostaglandinas/toxicidad , Ubiquitina Tiolesterasa/genética , Animales , Sitios de Unión , Isquemia Encefálica/enzimología , Isquemia Encefálica/patología , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Neuronas/enzimología , Neuronas/metabolismo , Ratas , Ubiquitina Tiolesterasa/biosíntesis
14.
Ann Oncol ; 26(11): 2311-7, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26362568

RESUMEN

BACKGROUND: Follicular lymphoma (FL) is the most common indolent non-Hodgkin lymphoma, with median age at diagnosis in the seventh decade. FL in young adults (YAs), defined as diagnosis at ≤40 years, is uncommon. No standard approaches exist guiding the treatment of YA FL, and little is known about their disease characteristics and outcomes. To gain further insights into YA FL, we analyzed the National LymphoCare Study (NLCS) to describe characteristics, initial treatments, and outcomes in this population versus patients aged >40 years. PATIENTS AND METHODS: Using the NLCS database, we stratified FL patients by age: 18-40 (YA), 41-60, 61-70, 71-80, and >80 years. Survival probability was estimated using Kaplan-Meier methodology. We examined associations between age and survival using hazard ratios and 95% confidence intervals (CIs) from multivariable Cox models. RESULTS: Of 2652 eligible FL patients in the NLCS, 164 (6%) were YAs. Of YA patients, 69% had advanced disease, 80% had low-grade histology, and 50% had good-risk disease according to the Follicular Lymphoma International Prognostic Index (FLIPI). Nineteen percent underwent observation, 12% received rituximab monotherapy, and 46% received chemoimmunotherapy [in 59% of these: R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone)]. With a median follow-up of 8 years, overall survival (OS) at 2, 5, and 8 years was 98% (95% CI 93-99), 94% (95% CI 89-97), and 90% (95% CI 83-94), respectively. Median progression-free survival (PFS) was 7.3 years (95% CI 5.6-not reached). CONCLUSIONS: In one of the largest cohorts of YA FL patients treated in the rituximab era, disease characteristics and outcomes were similar to patients aged 41-60 years, with favorable OS and PFS in YAs. Longer-term outcomes and YA-specific survivorship concerns should be considered when defining management. These data may not support the need for more aggressive therapies in YA FL. CLINICAL TRIAL NUMBER: Roche/Genentech ML01377 (U2963n).


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Linfoma Folicular/diagnóstico , Linfoma Folicular/tratamiento farmacológico , Rituximab/administración & dosificación , Adulto , Factores de Edad , Estudios de Cohortes , Ciclofosfamida/administración & dosificación , Doxorrubicina/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Linfoma Folicular/mortalidad , Masculino , Prednisona/administración & dosificación , Estudios Prospectivos , Sistema de Registros , Tasa de Supervivencia/tendencias , Resultado del Tratamiento , Vincristina/administración & dosificación , Adulto Joven
15.
Br J Cancer ; 111(7): 1255-61, 2014 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-25144626

RESUMEN

The dismal outlook for patients with the most aggressive and common form of adult brain cancer, glioblastoma (GBM), motivates a search for new therapeutic strategies and targets for this aggressive disease. Here we review the findings to date on the role of Eph family receptor tyrosine kinases and their ephrin ligands in brain cancer. Expression of the Eph family of cell surface proteins is generally downregulated to very low levels in normal adult tissues making them particularly attractive for directed therapeutic targeting. Recent Eph targeting studies in pre-clinical models of GBM have been very encouraging and may provide an avenue to treat these highly refractory aggressive tumours.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Receptores de la Familia Eph/antagonistas & inhibidores , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Ensayos de Selección de Medicamentos Antitumorales , Efrinas/fisiología , Glioblastoma/tratamiento farmacológico , Humanos , Terapia Molecular Dirigida , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Receptores de la Familia Eph/genética , Receptores de la Familia Eph/metabolismo , Transducción de Señal
16.
Colloids Surf B Biointerfaces ; 116: 687-94, 2014 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-24309136

RESUMEN

In vitro motility assays are readily used to simplify the complex environments within the cell and in muscle tissue. These assays have afforded considerable insight into the fundamentals of their underlying biophysics, interactions with cargo, intracellular regulation, and motor cooperation/competition. Extension of the standard in vitro motility assay into a more automated and cost-effective fluidic design while providing availability to the scientific community without expertise in lithographic fabrication is critical for the continued advancement of the field. In this work, we utilized a standard plasma cleaner to oxidize the widely prevalent material polydimethylsiloxane (PDMS) to create flow cells that could be used for in vitro motility assays. Our analysis indicated that a 40 min pre-treatment of the PDMS with plasma exposure resulted in optimal bundle motility. This finding was attributed to the condition at which the least amount of oxygen permeates the PDMS slab, enters the motility buffer, and oxidizes the motor proteins. Based on these findings, we developed a method for constructing microfluidic devices from glass and plasma-treated PDMS molds in which motility could be observed.


Asunto(s)
Dimetilpolisiloxanos/química , Técnicas In Vitro , Plasma/química , Animales , Técnicas Analíticas Microfluídicas/instrumentación , Oxidación-Reducción , Conejos
17.
Osteoporos Int ; 25(1): 349-57, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24136103

RESUMEN

UNLABELLED: Ibandronate reduces the risk of vertebral and non-vertebral fractures versus placebo in postmenopausal women with osteoporosis. This analysis, in which fractures were reported as safety events, showed that long-term use of ibandronate was associated with low fracture rates over 5 years of treatment. INTRODUCTION: A previous post-hoc meta-analysis of 2-3 year studies found that ibandronate regimens with annual cumulative exposure (ACE) of ≥10.8 mg reduced the risk of vertebral and nonvertebral fractures (NVFs) versus placebo in postmenopausal women. This post-hoc analysis used individual patient data from the 2-year monthly oral ibandronate in ladies (MOBILE) and dosing intravenous administration (DIVA) studies, including the 3-year long-term extensions (LTEs), to assess fracture risk in patients treated with ibandronate for 5 years. METHODS: Patients treated for 2 years in MOBILE with monthly oral ibandronate 150 mg (n = 176) and in DIVA with IV ibandronate every 2 months 2 mg (n = 253) or quarterly 3 mg (n = 263) who continued on the same regimens for 3 additional years in the LTEs were included. Three-year placebo data (n = 1,924) were obtained from the ibandronate osteoporosis vertebral fracture trial in North America and Europe (BONE) and IV Fracture Prevention trials. The primary endpoint was clinical fracture rate; clinical fracture data were collected as adverse events. Time to fracture was analyzed using Kaplan-Meier and statistical analysis was conducted using the log-rank test. All clinical fractures included all NVFs and symptomatic vertebral fractures. RESULTS: For ibandronate regimens with ACE ≥10.8 mg, time to fracture was significantly longer for all clinical fractures, NVFs, and clinical vertebral fractures versus placebo (P = 0.005). For all fracture types, the rate of fracture appeared stable during the 5-year treatment period. CONCLUSION: In women with postmenopausal osteoporosis, continuous treatment with ibandronate over 5 years results in low sustained clinical fracture rate.


Asunto(s)
Conservadores de la Densidad Ósea/administración & dosificación , Difosfonatos/administración & dosificación , Fracturas Osteoporóticas/prevención & control , Administración Oral , Anciano , Densidad Ósea/efectos de los fármacos , Conservadores de la Densidad Ósea/uso terapéutico , Difosfonatos/uso terapéutico , Esquema de Medicación , Europa (Continente)/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Ácido Ibandrónico , Infusiones Intravenosas , Persona de Mediana Edad , Osteoporosis Posmenopáusica/tratamiento farmacológico , Osteoporosis Posmenopáusica/fisiopatología , Fracturas Osteoporóticas/epidemiología , Ensayos Clínicos Controlados Aleatorios como Asunto , Fracturas de la Columna Vertebral/epidemiología , Fracturas de la Columna Vertebral/prevención & control , Estados Unidos/epidemiología
18.
Intern Med J ; 43(11): 1237-9, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24237645

RESUMEN

Multifocal motor neuropathy is frequently an asymmetrical neuropathy predominantly affecting the upper limbs. Patients present with weakness, fasciculations and distal muscle wasting. Hypertrophy of muscles is very infrequently reported. We present two cases of multifocal motor neuropathy with upper limb muscle hypertrophy and discuss possible pathophysiological mechanisms. Botulinum toxin may be useful to alleviate cramp.


Asunto(s)
Polineuropatías/diagnóstico , Extremidad Superior/patología , Toxinas Botulínicas/uso terapéutico , Femenino , Humanos , Hipertrofia , Masculino , Persona de Mediana Edad , Polineuropatías/tratamiento farmacológico
19.
J Viral Hepat ; 20(10): 708-14, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24010645

RESUMEN

Hepatitis C virus (HCV) treatment is rapidly changing but little is known about patients' attitudes and knowledge about HCV. This study used a cross-sectional survey to examine the relationship between HCV knowledge and attitudes towards HCV in patients with HCV mono-infection and HIV/HCV co-infection. Subsequently, an education intervention was developed with an abridged version of the cross-sectional survey administered before and after the education session to assess changes in knowledge and attitudes. 292 people participated in the cross-sectional survey, and 87 people participated in the education intervention. In the cross-sectional survey, the mean knowledge score regarding HCV was low (<50% of the total possible score). Mono-infected and co-infected individuals shared similar knowledge deficits and attitudes towards HCV despite having distinct demographic differences. Attitudes endorsed by patients included the following: 57% feared the consequences of HCV on their life, 37% felt HCV was not fatal, 27% did not believe they needed HCV medication, 21% felt ashamed of having HCV and 16% felt HCV treatment was not important. Attitudes that reflected indifference and shame towards HCV were associated with lower knowledge scores (HCV knowledge score of 15.1 vs. 17.5, P < 0.01 for indifference and 15.3 vs. 17.2 for shame, P = 0.02). The education intervention improved knowledge scores but did not modify the assessed attitudes. Intervention studies are needed to effectively change attitudes towards HCV infection and treatment.


Asunto(s)
Infecciones por VIH/complicaciones , Conocimientos, Actitudes y Práctica en Salud , Hepatitis C/psicología , Hepatitis C/terapia , Adulto , Estudios Transversales , Femenino , Educación en Salud/métodos , Humanos , Masculino , Persona de Mediana Edad
20.
Br J Pharmacol ; 169(5): 1166-77, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23586967

RESUMEN

BACKGROUND AND PURPOSE: Nebulized saline solutions are used in the treatment of multiple pulmonary diseases including cystic fibrosis (CF), asthma and chronic obstructive pulmonary disease (COPD). The benefits of these therapies include improved lung function, phlegm clearance and fewer lung infections. The thiocyanate anion (SCN) is a normal component of the airway epithelial lining fluid (ELF) secreted by pulmonary epithelia with antioxidant and host defence functions. We sought to test if SCN could be nebulized to combat lung infection by bolstering innate immune defence and antioxidant capacity. EXPERIMENTAL APPROACH: We established an effective antioxidant concentration of SCN in vitro using a bronchiolar epithelial cell line. We then developed a nebulization method of SCN in mice that increased ELF SCN above this concentration up to 12 h and used this method in a prolonged Pseudomonas aeruginosa infection model to test if increasing SCN improved host defence and infection outcomes. KEY RESULTS: SCN protected against cytotoxicity in vitro from acute and sustained exposure to inflammation-associated oxidative stress. Nebulized SCN effectively reduced bacterial load, infection-mediated morbidity and airway inflammation in mice infected with P. aeruginosa. SCN also sustained adaptive increases in reduced GSH in infected mice. CONCLUSIONS AND IMPLICATIONS: SCN is a dually protective molecule able to both enhance host defence and decrease tissue injury and inflammation as an antioxidant. Nebulized SCN could be developed to combat lung infections and inflammatory lung disease.


Asunto(s)
Antioxidantes/administración & dosificación , Enfermedades Pulmonares/tratamiento farmacológico , Infecciones por Pseudomonas/tratamiento farmacológico , Tiocianatos/administración & dosificación , Administración por Inhalación , Animales , Antioxidantes/farmacocinética , Carga Bacteriana , Líquido del Lavado Bronquioalveolar/citología , Líquido del Lavado Bronquioalveolar/inmunología , Líquido del Lavado Bronquioalveolar/microbiología , Recuento de Células , Línea Celular , Citocinas/inmunología , Humanos , Peróxido de Hidrógeno , Ácido Hipocloroso , Enfermedades Pulmonares/microbiología , Masculino , Ratones Endogámicos C57BL , Nebulizadores y Vaporizadores , Oxidantes , Peroxidasa , Peroxidasas/metabolismo , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa , Piocianina/metabolismo , Tiocianatos/sangre , Tiocianatos/farmacocinética
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