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1.
Clin Oral Investig ; 27(10): 5925-5933, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37606722

RESUMEN

OBJECTIVES: Periodontal disease has been linked to multiple systemic conditions, but the relationship with COVID-19 still needs to be elucidated. We hypothesized that periodontal disease may be associated with COVID-19 infection. MATERIALS AND METHODS: This study utilized cross-sectional data to establish the strength of the association between periodontal disease and COVID-19 infection. The University of Florida Health Center's i2b2 patient's registry was used to generate patient counts through ICD-10 diagnostic codes. Univariate descriptive statistics of the patient population and logistic regression to estimate odds ratios of associations between periodontal disease and COVID-19 infection were used for analysis. RESULTS: Patients with periodontal disease were 4.4 times more likely to be positively diagnosed with COVID-19 than patients without PD. Associations remained similar and robust (P value < 0.0001) after adjustment for age (OR = 4.34; 95% CI, 3.68-5.09), gender (OR = 4.46; 95% CI, 3.79-5.23), and smoking status (OR = 4.77; 95% CI, 4.04-5.59). Associations were smaller but remained robust (P value < 0.0001) after adjusting for race (OR = 2.83; 95% CI, 2.40-3.32), obesity (OR = 2.53; 95% CI, 2.14-2.98), diabetes (OR = 3.32; 95% CI, 2.81-3.90), and cardiovascular disease (OR = 2.68; 95% CI, 2.27-3.14). CONCLUSIONS: Periodontal disease is significantly associated with increased odds for COVID-19 infection. CLINICAL RELEVANCE: With the caveat of a cross-sectional study design, these results suggest that periodontal disease may increase the odds for COVID-19 infection.

2.
Biol Reprod ; 102(3): 607-619, 2020 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-31621839

RESUMEN

Heritable mitochondrial DNA (mtDNA) mutations are common, yet only a few recurring pathogenic mtDNA variants account for the majority of known familial cases in humans. Purifying selection in the female germline is thought to be responsible for the elimination of most harmful mtDNA mutations during oogenesis. Here we show that deleterious mtDNA mutations are abundant in ovulated mature mouse oocytes and preimplantation embryos recovered from PolG mutator females but not in their live offspring. This implies that purifying selection acts not in the maternal germline per se, but during post-implantation development. We further show that oocyte mtDNA mutations can be captured and stably maintained in embryonic stem cells and then reintroduced into chimeras, thereby allowing examination of the effects of specific mutations on fetal and postnatal development.


Asunto(s)
Blastocisto/metabolismo , ADN Mitocondrial/genética , Mutación , Oocitos/metabolismo , Animales , ADN Mitocondrial/metabolismo , Desarrollo Embrionario/genética , Femenino , Ratones , Mitocondrias/genética , Mitocondrias/metabolismo , Oogénesis/genética
3.
Phys Chem Chem Phys ; 20(25): 16949-16955, 2018 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-29873653

RESUMEN

LOV-domains are ubiquitous photosensory proteins that are commonly re-engineered to serve as powerful and versatile fluorescent proteins and optogenetic tools. The photoactive, flavin chromophore, however, is excited using short wavelengths of light in the blue and UV regions, which have limited penetration into biological samples and can cause photodamage. Here, we have used non-linear spectroscopy and microscopy of the fluorescent protein, iLOV, to reveal that functional variants of LOV can be activated to great effect by two non-resonant photons of lower energy, near infrared light, not only in solution but also in biological samples. The two photon cross section of iLOV has a significantly blue-shifted S0 → S1 transition compared with the one photon absorption spectrum, suggesting preferential population of excited vibronic states. It is highly likely, therefore, that the two photon absorption wavelength of engineered, LOV-based tools is tuneable. We also demonstrate for the first time two photon imaging using iLOV in human epithelial kidney cells. Consequently, two photon absorption by engineered, flavin-based bio-molecular tools can enable non-invasive activation with high depth resolution and the potential for not only improved image clarity but also enhanced spatiotemporal control for optogenetic applications.


Asunto(s)
Flavoproteínas/química , Colorantes Fluorescentes/química , Proteínas Luminiscentes/química , Imagen Óptica/métodos , Escherichia coli , Flavinas/química , Flavoproteínas/genética , Células HEK293 , Humanos , Rayos Infrarrojos , Microscopía de Fluorescencia por Excitación Multifotónica/métodos , Fotones , Conformación Proteica , Espectrometría de Fluorescencia/métodos
4.
J Theor Biol ; 395: 1-10, 2016 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-26829313

RESUMEN

Mathematical models of the interplay between disease dynamics and human behavioural dynamics can improve our understanding of how diseases spread when individuals adapt their behaviour in response to an epidemic. Accounting for behavioural mechanisms that determine uptake of infectious disease interventions such as vaccination and non-pharmaceutical interventions (NPIs) can significantly alter predicted health outcomes in a population. However, most previous approaches that model interactions between human behaviour and disease dynamics have modelled behaviour of these two interventions separately. Here, we develop and analyze an agent based network model to gain insights into how behaviour toward both interventions interact adaptively with disease dynamics (and therefore, indirectly, with one another) during the course of a single epidemic where an SIRV infection spreads through a contact network. In the model, individuals decide to become vaccinated and/or practice NPIs based on perceived infection prevalence (locally or globally) and on what other individuals in the network are doing. We find that introducing adaptive NPI behaviour lowers vaccine uptake on account of behavioural feedbacks, and also decreases epidemic final size. When transmission rates are low, NPIs alone are as effective in reducing epidemic final size as NPIs and vaccination combined. Also, NPIs can compensate for delays in vaccine availability by hindering early disease spread, decreasing epidemic size significantly compared to the case where NPI behaviour does not adapt to mitigate early surges in infection prevalence. We also find that including adaptive NPI behaviour strongly mitigates the vaccine behavioural feedbacks that would otherwise result in higher vaccine uptake at lower vaccine efficacy as predicted by most previous models, and the same feedbacks cause epidemic final size to remain approximately constant across a broad range of values for vaccine efficacy. Finally, when individuals use local information about others' behaviour and infection prevalence, instead of population-level information, infection is controlled more efficiently through ring vaccination, and this is reflected in the time evolution of pair correlations on the network. This model shows that accounting for both adaptive NPI behaviour and adaptive vaccinating behaviour regarding social effects and infection prevalence can result in qualitatively different predictions than if only one type of adaptive behaviour is modelled.


Asunto(s)
Control de Enfermedades Transmisibles , Enfermedades Transmisibles/epidemiología , Modelos Biológicos , Humanos
5.
PLoS Comput Biol ; 11(6): e1004291, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26047028

RESUMEN

Theoretical models of disease dynamics on networks can aid our understanding of how infectious diseases spread through a population. Models that incorporate decision-making mechanisms can furthermore capture how behaviour-driven aspects of transmission such as vaccination choices and the use of non-pharmaceutical interventions (NPIs) interact with disease dynamics. However, these two interventions are usually modelled separately. Here, we construct a simulation model of influenza transmission through a contact network, where individuals can choose whether to become vaccinated and/or practice NPIs. These decisions are based on previous experience with the disease, the current state of infection amongst one's contacts, and the personal and social impacts of the choices they make. We find that the interventions interfere with one another: because of negative feedback between intervention uptake and infection prevalence, it is difficult to simultaneously increase uptake of all interventions by changing utilities or perceived risks. However, on account of vaccine efficacy being higher than NPI efficacy, measures to expand NPI practice have only a small net impact on influenza incidence due to strongly mitigating feedback from vaccinating behaviour, whereas expanding vaccine uptake causes a significant net reduction in influenza incidence, despite the reduction of NPI practice in response. As a result, measures that support expansion of only vaccination (such as reducing vaccine cost), or measures that simultaneously support vaccination and NPIs (such as emphasizing harms of influenza infection, or satisfaction from preventing infection in others through both interventions) can significantly reduce influenza incidence, whereas measures that only support expansion of NPI practice (such as making hand sanitizers more available) have little net impact on influenza incidence. (However, measures that improve NPI efficacy may fare better.) We conclude that the impact of interference on programs relying on multiple interventions should be more carefully studied, for both influenza and other infectious diseases.


Asunto(s)
Brotes de Enfermedades , Vacunas contra la Influenza , Gripe Humana , Modelos Biológicos , Modelos Estadísticos , Vacunación/estadística & datos numéricos , Biología Computacional , Brotes de Enfermedades/prevención & control , Brotes de Enfermedades/estadística & datos numéricos , Conductas Relacionadas con la Salud , Humanos , Gripe Humana/epidemiología , Gripe Humana/prevención & control , Gripe Humana/transmisión
6.
Int J Sport Nutr Exerc Metab ; 26(1): 55-64, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26251549

RESUMEN

Athletes require sufficient nutrition knowledge and skills to enable appropriate selection and consumption of food and fluids to meet their health, body composition, and performance needs. This article reports the nutrition knowledge and dietary habits of male football (soccer) players in Australia. Players age 18 years and older were recruited from 1 A-League club (professional) and 4 National Premier League clubs (semiprofessional). No significant difference in general nutrition knowledge (GNK; 54.1% ± 13.4%; 56.8% ± 11.7%; M ± SD), t(71) = -0.91, p = .37, or sports nutrition knowledge (SNK; 56.9% ± 15.5%; 61.3% ± 15.9%), t(71) = -1.16, p = .25) were noted between professional (n = 29) and semiprofessional (n = 44) players. In general, players lacked knowledge in regard to food sources and types of fat. Although nutrition knowledge varied widely among players (24.6-82.8% correct responses), those who had recently studied nutrition answered significantly more items correctly than those who reported no recent formal nutrition education (62.6% ± 11.9%; 54.0% ± 11.4%), t(67) = 2.88, p = .005). Analysis of 3-day estimated food diaries revealed both professionals (n = 10) and semiprofessionals (n = 31) consumed on average less carbohydrate (3.5 ± 0.8 gC/kg; 3.9 ± 1.8 gC/kg) per day than football-specific recommendations (FIFA Medical and Assessment Research Centre [F-MARC]: 5-10 gC/kg). There was a moderate, positive correlation between SNK and carbohydrate intake (n = 41, ρ = 0.32, p = .04), indicating that players who exhibited greater SNK had higher carbohydrate intakes. On the basis of these findings, male football players in Australia would benefit from nutrition education targeting carbohydrate and fat in an attempt to improve nutrition knowledge and dietary practices.


Asunto(s)
Atletas , Conducta Alimentaria , Conocimientos, Actitudes y Práctica en Salud , Fútbol , Ciencias de la Nutrición y del Deporte , Adolescente , Adulto , Australia , Registros de Dieta , Humanos , Masculino , Necesidades Nutricionales , Encuestas y Cuestionarios , Adulto Joven
7.
Inorg Chem ; 53(1): 383-92, 2014 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-24328217

RESUMEN

The synthesis, crystal structures, and Raman spectra of seven plutonium chloride compounds are presented. The materials are based upon Pu(VI)O2Cl4(2-) and Pu(IV)Cl6(2-) anions that are charge balanced by protonated pyridinium cations. The single crystal X-ray structures show a variety of donor-acceptor interactions between the plutonium perhalo anions and the cationic pyridine groups. Complementary Raman spectra show that these interactions can be probed through the symmetric vibrational mode of the plutonyl moiety. Unlike previously reported studies in similar uranyl(VI) systems, the facile redox chemistry of plutonium in aqueous solution has demonstrated the feasibility of using not only the An(VI)O2Cl4(2-) anion with approximate D4h symmetry but also the approximately Oh An(IV)Cl6(2-) anion in order to manipulate both the structure and dimensionality of such hybrid materials.

8.
Artículo en Inglés | MEDLINE | ID: mdl-38995209

RESUMEN

BACKGROUND: We aimed to examine the common adverse drug reactions (ADRs) of metoclopramide, FDA-approved for treating many gastrointestinal conditions including gastroparesis, and prucalopride, FDA-approved for treating chronic idiopathic constipation but used off-label for other gastrointestinal conditions including gastroparesis. RESEARCH DESIGN AND METHODS: The FDA Adverse Event Reporting System (FAERS) was analyzed from January 2013 to December 2023. ADR reports regarding use of only metoclopramide or prucalopride were analyzed following exclusion of reports indicating use for treatment of non-gastrointestinal conditions. RESULTS: Analysis of 1,085 reports on metoclopramide revealed tardive dyskinesia (n = 393, 36.2%) and dystonia (n = 170, 15.7%) among the most reported ADRs in addition to QTc prolongation (n = 16, 1.5%) with progression to Torsade de pointes (n = 5, 0.5%) and triggering of pheochromocytoma crisis (n = 24, 2.2%). Analysis of 865 reports on prucalopride revealed headache (n = 120, 13.9%), diarrhea (n = 116, 13.4%), and abdominal pain (n = 100, 11.6%) as the most common ADRs with 22 reports (2.5%) of dystonia with the use of prucalopride. CONCLUSIONS: This FAERS database analysis shows post-marketing reports of ADRs from metoclopramide most frequently include tardive dyskinesia, dystonia, and tremor in addition to potentially fatal arrhythmias such as Torsade de pointes. Consumers of prucalopride may also be at risk of dystonia and other ADRs.

9.
bioRxiv ; 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38501121

RESUMEN

Glioblastoma (GBM) poses a significant challenge in clinical oncology due to its aggressive nature, heterogeneity, and resistance to therapies. Cancer stem cells (CSCs) play a critical role in GBM, particularly in treatment-resistance and tumor relapse, emphasizing the need to comprehend the mechanisms regulating these cells. Also, their multifaceted contributions to the tumor-microenvironment (TME) underline their significance, driven by their unique properties. This study aimed to characterize glioblastoma stem cells (GSCs), specifically slow-cycling cells (SCCs), in an immunocompetent murine GBM model to explore their similarities with their human counterparts. Using the KR158 mouse model, we confirmed that SCCs isolated from this model exhibited key traits and functional properties akin to human SCCs. KR158 murine SCCs, expanded in the gliomasphere assay, demonstrated sphere forming ability, self-renewing capacity, positive tumorigenicity, enhanced stemness and resistance to chemotherapy. Together, our findings validate the KR158 murine model as a framework to investigate GSCs and SCCs in GBM-pathology, and explore specifically the SCC-immune system communications, understand their role in disease progression, and evaluate the effect of therapeutic strategies targeting these specific connections.

10.
Cells ; 13(11)2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38891070

RESUMEN

Glioblastoma (GBM) poses a significant challenge in clinical oncology due to its aggressive nature, heterogeneity, and resistance to therapies. Cancer stem cells (CSCs) play a critical role in GBM, particularly in treatment resistance and tumor relapse, emphasizing the need to comprehend the mechanisms regulating these cells. Also, their multifaceted contributions to the tumor microenvironment (TME) underline their significance, driven by their unique properties. This study aimed to characterize glioblastoma stem cells (GSCs), specifically slow-cycling cells (SCCs), in an immunocompetent murine GBM model to explore their similarities with their human counterparts. Using the KR158 mouse model, we confirmed that SCCs isolated from this model exhibited key traits and functional properties akin to human SCCs. KR158 murine SCCs, expanded in the gliomasphere assay, demonstrated sphere forming ability, self-renewing capacity, positive tumorigenicity, enhanced stemness and resistance to chemotherapy. Together, our findings validate the KR158 murine model as a framework to investigate GSCs and SCCs in GBM pathology, and explore specifically the SCC-immune system communications, understand their role in disease progression, and evaluate the effect of therapeutic strategies targeting these specific connections.


Asunto(s)
Células Madre Neoplásicas , Esferoides Celulares , Animales , Ratones , Células Madre Neoplásicas/patología , Células Madre Neoplásicas/metabolismo , Esferoides Celulares/patología , Humanos , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/inmunología , Glioma/patología , Glioma/inmunología , Línea Celular Tumoral , Glioblastoma/patología , Glioblastoma/inmunología , Inmunocompetencia , Microambiente Tumoral , Modelos Animales de Enfermedad , Clasificación del Tumor
11.
Inorg Chem ; 52(4): 2060-9, 2013 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-23368709

RESUMEN

Six novel uranyl terpyridine aromatic carboxylate coordination polymers, [UO(2)(C(6)H(2)O(4)S)(C(15)H(11)N(3))] (1), [UO(2)(C(6)H(2)O(4)S)(C(15)H(10)N(3)Cl)]·H(2)O (2), [UO(2)(C(8)H(4)O(4))(C(15)H(11)N(3))] (3), [UO(2)(C(8)H(4)O(4))(C(15)H(10)N(3)Cl)] (4), [UO(2)(C(12)H(6)O(4))(C(15)H(11)N(3))] (5), and [UO(2)(C(12)H(6)O(4))(C(15)H(10)N(3)Cl)] (6), were synthesized under solvothermal conditions and characterized by single-crystal and powder X-ray diffraction and luminescence and UV-vis spectroscopy. Compounds 1, 2, and 5 crystallize as molecular uranyl dimers, whereas compounds 3, 4, and 6 contain ladder motifs of uranyl centers. Fluorescence spectra of 1-4 show characteristic UO(2)(2+) emission, wherein bathochromic and hypsochromic shifts are noted as a function of organic species. In contrast, uranyl emission from 5 and 6 is quenched by the naphthalene dicarboxylic acid linker molecules.


Asunto(s)
Ácidos Carboxílicos/química , Luminiscencia , Compuestos Organometálicos/química , Polímeros/química , Piridinas/química , Uranio/química , Modelos Moleculares , Estructura Molecular , Compuestos Organometálicos/síntesis química , Polímeros/síntesis química
12.
Inorg Chem ; 51(6): 3883-90, 2012 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-22360688

RESUMEN

We have investigated the assembly of a two-dimensional coordination polymer, Nd(2)(C(6)H(2)N(2)O(4))(2)(C(2)O(4))(H(2)O)(2), that has been prepared from the hydrothermal reaction of Nd(NO(3))(3)·6H(2)O and 2,3-pyrazinedicarboxylic acid (H(2)pzdc). In situ oxalate formation as observed in this system has been been investigated using (1)H and (13)C nuclear magnetic resonance spectroscopy, and a pathway for C(2)O(4)(2-) anion formation under hydrothermal conditions has been elucidated. The oxalate ligands found in Nd(2)(C(6)H(2)N(2)O(4))(2)(C(2)O(4))(H(2)O)(2) result from the oxidation of H(2)pzdc, which proceeds through intermediates, such as 2-pyrazinecarboxylic acid (2-pzca), 2-hydroxyacetamide, 3-amino-2-hydroxy-3-oxopropanoic acid, 2-hydroxymalonic acid, 2-oxoacetic acid (glyoxylic acid), and glycolic acid. The species are generated through a ring-opening that occurs via cleavage of the C-N bond of the pyrazine ring, followed by hydrolysis/oxidation of the resulting species.

13.
Biomolecules ; 12(10)2022 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-36291648

RESUMEN

Aberrations in lipid and lipoprotein metabolic pathways can lead to numerous diseases, including cardiovascular disease, diabetes, neurological disorders, and cancer. The integration of quantitative lipid and lipoprotein profiling of human plasma may provide a powerful approach to inform early disease diagnosis and prevention. In this study, we leveraged data-driven quantitative targeted lipidomics and proteomics to identify specific molecular changes associated with different metabolic risk categories, including hyperlipidemic, hypercholesterolemic, hypertriglyceridemic, hyperglycemic, and normolipidemic conditions. Based on the quantitative characterization of serum samples from 146 individuals, we have determined individual lipid species and proteins that were significantly up- or down-regulated relative to the normolipidemic group. Then, we established protein-lipid topological networks for each metabolic category and linked dysregulated proteins and lipids with defined metabolic pathways. To evaluate the differentiating power of integrated lipidomics and proteomics data, we have built an artificial neural network model that simultaneously and accurately categorized the samples from each metabolic risk category based on the determined lipidomics and proteomics profiles. Together, our findings provide new insights into molecular changes associated with metabolic risk conditions, suggest new condition-specific associations between apolipoproteins and lipids, and may inform new biomarker discovery in lipid metabolism-associated disorders.


Asunto(s)
Trastornos del Metabolismo de los Lípidos , Lipidómica , Humanos , Proteómica , Metabolismo de los Lípidos , Lípidos , Biomarcadores/metabolismo
14.
PLoS One ; 17(10): e0276649, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36279295

RESUMEN

BACKGROUND: Genetic variants in apolipoprotein L1 (APOL1), a protein that protects humans from infection with African trypanosomes, explain a substantial proportion of the excess risk of chronic kidney disease affecting individuals with sub-Saharan ancestry. The mechanisms by which risk variants damage kidney cells remain incompletely understood. In preclinical models, APOL1 expressed in podocytes can lead to significant kidney injury. In humans, studies in kidney transplant suggest that the effects of APOL1 variants are predominantly driven by donor genotype. Less attention has been paid to a possible role for circulating APOL1 in kidney injury. METHODS: Using liquid chromatography-tandem mass spectrometry, the concentrations of APOL1 were measured in plasma and urine from participants in the Seattle Kidney Study. Asymmetric flow field-flow fractionation was used to evaluate the size of APOL1-containing lipoprotein particles in plasma. Transgenic mice that express wild-type or risk variant APOL1 from an albumin promoter were treated to cause kidney injury and evaluated for renal disease and pathology. RESULTS: In human participants, urine concentrations of APOL1 were correlated with plasma concentrations and reduced kidney function. Risk variant APOL1 was enriched in larger particles. In mice, circulating risk variant APOL1-G1 promoted kidney damage and reduced podocyte density without renal expression of APOL1. CONCLUSIONS: These results suggest that plasma APOL1 is dynamic and contributes to the progression of kidney disease in humans, which may have implications for treatment of APOL1-associated kidney disease and for kidney transplantation.


Asunto(s)
Apolipoproteína L1 , Insuficiencia Renal Crónica , Humanos , Ratones , Animales , Apolipoproteína L1/genética , Apolipoproteína L1/metabolismo , Apolipoproteínas/genética , Riñón/patología , Insuficiencia Renal Crónica/genética , Insuficiencia Renal Crónica/patología , Ratones Transgénicos , Modelos Animales de Enfermedad , Albúminas
15.
J Neurophysiol ; 105(6): 3002-9, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21389300

RESUMEN

In a subset of hereditary retinal diseases, early photoreceptor degeneration causes rapidly progressive blindness in children. To better understand how retinal development may interact with degenerative processes, we compared spontaneous and light-evoked activity among retinal ganglion cells in rd1 and rd10 mice, strains with closely related retinal disease. In each, a mutation in the Pde6b gene causes photoreceptor dysfunction and death, but in rd10 mice degeneration starts after a peak in developmental plasticity of retinal circuitry and thereafter progresses more slowly. In vitro multielectrode action potential recordings revealed that spontaneous waves of correlated ganglion cell activity comparable to those in wild-type mice were present in rd1 and rd10 retinas before eye opening [postnatal day (P) 7 to P8]. In both strains, spontaneous firing rates increased by P14-P15 and were many times higher by 4-6 wk of age. Among rd1 ganglion cells, all responses to light had disappeared by ~P28, yet in rd10 retinas vigorous ON and OFF responses were maintained well beyond this age and were not completely lost until after P60. This difference in developmental time course separates mechanisms underlying the hyperactivity from those that alter light-driven responses in rd10 retinas. Moreover, several broad physiological groups of cells remained identifiable according to response polarity and time course as late as P60. This raises hope that visual function might be preserved or restored despite ganglion cell hyperactivity seen in inherited retinal degenerations, particularly if treatment or manipulation of early developmental plasticity were to be timed appropriately.


Asunto(s)
Potenciales Evocados Visuales/fisiología , Luz , Degeneración Retiniana/genética , Degeneración Retiniana/patología , Células Ganglionares de la Retina/fisiología , Factores de Edad , Animales , Animales Recién Nacidos , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 6/genética , Potenciales Evocados Visuales/genética , Técnicas In Vitro , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Mutación/genética , Estimulación Luminosa/métodos , Retina/citología
16.
Cell Biol Toxicol ; 27(1): 13-40, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20589437

RESUMEN

Many anticancer drugs are myelotoxic and cause bone marrow depression; however, generally, the marrow/blood returns to normal after treatment. Nevertheless, after the administration of some anti-neoplastic agents (e.g. busulphan, BU) under conditions as yet undefined, the marrow may begin a return towards normal, but normality may not be achieved, and late-stage/residual marrow injury may be evident. The present studies were conducted to develop a short-term mouse model (a 'screen') to identify late-stage/residual marrow injury using a brief regimen of drug administration. Female BALB/c mice were treated with BU, doxorubicin (DOX), cisplatin (CISPLAT) or cyclophosphamide (CYCLOPHOS) on days 1, 3 and 5. In 'preliminary studies', a maximum tolerated dose (MTD) for each drug was determined for use in 'main studies'. In main studies, mice were treated with vehicle (control), low and high (the MTD) dose levels of each agent. Necropsies were performed, and blood parameters and femoral/humeral nucleated marrow cell counts (FNCC/HNCC) were assessed on six occasions (from days 1 to 60/61 post-dosing). Late-stage/residual changes were apparent in BU-treated mice at day 61 post-dosing: RBC, Hb and haematocrit were reduced, mean cell volume/mean cell haemoglobin were increased and platelet and FNCC counts were decreased. Mice given DOX, CISPLAT and CYCLOPHOS, in general, showed no clear late-stage/residual effects (day 60/61). It was concluded that a brief regimen of drug administration, at an MTD, with assessment at day 60/61 post-dosing was a suitable short-term method/screen in the mouse for detecting late-stage/residual marrow injury for BU, a drug shown to exhibit these effects in man.


Asunto(s)
Antineoplásicos/toxicidad , Busulfano/toxicidad , Cisplatino/toxicidad , Ciclofosfamida/toxicidad , Doxorrubicina/toxicidad , Animales , Células Sanguíneas/citología , Células Sanguíneas/efectos de los fármacos , Células de la Médula Ósea/citología , Células de la Médula Ósea/efectos de los fármacos , Recuento de Células , Femenino , Hematócrito , Hemoglobinas/análisis , Ratones , Ratones Endogámicos BALB C
17.
Proc Natl Acad Sci U S A ; 105(9): 3380-5, 2008 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-18299575

RESUMEN

Mutations in a group of genes that contribute to ciliary function cause Bardet-Biedl syndrome (BBS). Most studies of BBS have focused on primary, sensory cilia. Here, we asked whether loss of BBS proteins would also affect motile cilia lining the respiratory tract. We found that BBS genes were expressed in human airway epithelia, and BBS2 and BBS4 localized to cellular structures associated with motile cilia. Although BBS proteins were not required for ciliogenesis, their loss caused structural defects in a fraction of cilia covering mouse airway epithelia. The most common abnormality was bulges filled with vesicles near the tips of cilia. We discovered this same misshapen appearance in airway cilia from Bbs1, Bbs2, Bbs4, and Bbs6 mutant mice. The structural abnormalities were accompanied by functional defects; ciliary beat frequency was reduced in Bbs mutant mice. Previous reports suggested BBS might increase the incidence of asthma. However, compared with wild-type controls, neither airway hyperresponsiveness nor inflammation increased in Bbs2(-/-) or Bbs4(-/-) mice immunized with ovalbumin. Instead, these animals were partially protected from airway hyperresponsiveness. These results emphasize the role of BBS proteins in both the structure and function of motile cilia. They also invite additional scrutiny of motile cilia dysfunction in patients with this disease.


Asunto(s)
Síndrome de Bardet-Biedl/patología , Cilios/patología , Proteínas Asociadas a Microtúbulos/genética , Proteínas/genética , Mucosa Respiratoria/patología , Animales , Forma de la Célula , Cilios/química , Cilios/fisiología , Chaperoninas del Grupo II , Humanos , Hipersensibilidad/etiología , Masculino , Ratones , Ratones Noqueados , Chaperonas Moleculares/genética
19.
Proc Natl Acad Sci U S A ; 104(49): 19422-7, 2007 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-18032602

RESUMEN

Bardet-Biedl syndrome (BBS) is a genetically heterogeneous disorder that results in retinal degeneration, obesity, cognitive impairment, polydactyly, renal abnormalities, and hypogenitalism. Of the 12 known BBS genes, BBS1 is the most commonly mutated, and a single missense mutation (M390R) accounts for approximately 80% of BBS1 cases. To gain insight into the function of BBS1, we generated a Bbs1(M390R/M390R) knockin mouse model. Mice homozygous for the M390R mutation recapitulated aspects of the human phenotype, including retinal degeneration, male infertility, and obesity. The obese mutant mice were hyperphagic and hyperleptinemic and exhibited reduced locomotor activity but no elevation in mean arterial blood pressure. Morphological evaluation of Bbs1 mutant brain neuroanatomy revealed ventriculomegaly of the lateral and third ventricles, thinning of the cerebral cortex, and reduced volume of the corpus striatum and hippocampus. Similar abnormalities were also observed in the brains of Bbs2(-/-), Bbs4(-/-), and Bbs6(-/-) mice, establishing these neuroanatomical defects as a previously undescribed BBS mouse model phenotype. Ultrastructural examination of the ependymal cell cilia that line the enlarged third ventricle of the Bbs1 mutant brains showed that, whereas the 9 + 2 arrangement of axonemal microtubules was intact, elongated cilia and cilia with abnormally swollen distal ends were present. Together with data from transmission electron microscopy analysis of photoreceptor cell connecting cilia, the Bbs1 M390R mutation does not affect axonemal structure, but it may play a role in the regulation of cilia assembly and/or function.


Asunto(s)
Síndrome de Bardet-Biedl/genética , Síndrome de Bardet-Biedl/patología , Modelos Animales de Enfermedad , Ratones/genética , Proteínas Asociadas a Microtúbulos/genética , Animales , Ventrículos Cerebrales/patología , Cilios/ultraestructura , Masculino , Mutación , Obesidad/genética , Enfermedades de la Retina/genética , Cola del Espermatozoide/patología
20.
Math Biosci Eng ; 16(5): 3753-3770, 2019 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-31499635

RESUMEN

Dynamic transmission models of influenza are sometimes used in decision-making to identify which vaccination strategies might best reduce influenza-associated health burdens. Our goal was to use laboratory confirmed influenza cases to fit model parameters in an age-structured, two-type (influenza A/B) dynamic model of influenza. We compared the fitted model under two fitting methodologies: using longitudinal weekly case notification data versus using cross-sectional age-stratified cumulative case notification data. The longitudinal data came from a Canadian province (Ontario)whereasthecross-sectionaldatacamefromthenationallevel(allofCanada). Wefindthatthe longitudinal fitting method provides best fitting parameter sets that have a higher variance between the respective parameters in each set than the cross-sectional cumulative case method. Model predictions-particularly for influenza A-are very different for the two fitting methodologies under hypothetical vaccination scenarios that expand coverage in either younger age classes or older age classes: the cross-sectional method predicts much larger decreases in total cases under expanded vaccine coverage than the longitudinal method. Also, the longitudinal method predicts that vaccinating younger age groups yields greater declines in total cases than vaccinating older age groups, whereas the cross- sectional method predicts the opposite. We conclude that model predictions of vaccination impacts under different strategies may differ at national versus provincial levels. Finally, we discuss whether usinglongitudinalversuscross-sectionaldatainmodelfittingmaygeneratefurtherdifferencesinmodel predictions (above and beyond population-specific differences) and how such a hypothesis could be tested in future studies.


Asunto(s)
Vacunas contra la Influenza/uso terapéutico , Gripe Humana/epidemiología , Gripe Humana/transmisión , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Algoritmos , Número Básico de Reproducción , Niño , Preescolar , Simulación por Computador , Estudios Transversales , Humanos , Lactante , Recién Nacido , Estudios Longitudinales , Persona de Mediana Edad , Modelos Teóricos , Dinámicas no Lineales , Ontario/epidemiología , Vacunación/métodos , Adulto Joven
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