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1.
Res Pract Thromb Haemost ; 5(7): e12599, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34761154

RESUMO

BACKGROUND: Existing adult patient pharmacokinetic (PK) data from the published Advate vs Kovaltry PK crossover study were used for this validation study. This data set is appropriate for qualification, given that it has not been previously submitted to Web-Accessible Population Pharmacokinetic Service-Hemophilia (WAPPS-Hemo) and will not have impacted the WAPPS-Hemo models for Kovaltry. OBJECTIVE: To compare the population PK parameters for Kovaltry (BAY 81-8973) derived from the WAPPS-Hemo models with PK parameters derived from noncompartmental analysis (NCA), using a validation PK dataset. METHODS: The qualification data set included Kovaltry factor activity (10 samples per infusion) and anthropometric data for 18 patients. Two analyses were performed comparison of Bayesian forecasting from the WAPPS-Hemo models versus NCA using the full 10-sample data set; and comparison of Bayesian forecasting using the full versus reduced 4- and 3-sample data sets. Agreement between outcomes was assessed by quantifying the variability and bias of the error. RESULTS: Comparison of WAPPS-Hemo models versus NCA led to well-correlated outcomes despite a systematic overprediction of clearance. Population PK models demonstrated greater consistency with NCA on one-stage data, compared with chromogenic data. WAPPS-Hemo model results were consistent in reduced sampling compared to full sampling. Inclusion of a 48-hour time point in the reduced sampling greatly improved the consistency with full sampling. DISCUSSION: Qualification of population PK models and their use for Bayesian forecasting in full and reduced sampling is an essential step toward their validation. The evaluations performed in this study support the confidence of PK parameter estimates provided by the models.

2.
Thyroid ; 31(10): 1597-1602, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34114495

RESUMO

Background: We report the therapeutic use of K1-70™, a thyrotropin receptor (TSHR) antagonist monoclonal antibody, in a patient with follicular thyroid cancer (FTC), Graves' disease (GD), and Graves' ophthalmopathy (GO). Methods: A 51-year-old female patient, who smoked, presented in October 2014 with FTC complicated by GD, high levels of TSHR autoantibodies with high thyroid stimulating antibody (TSAb) activity, and severe GO. K1-70 was administered at 3 weekly intervals with the dose adjusted to block TSAb activity. Her cancer was managed with lenvatinib and radioiodine therapy. Results: Following initiation of K1-70 therapy, TSAb activity measured in serum decreased and GO (proptosis and inflammation) improved. On K1-70 monotherapy during the pause in lenvatinib, several metastatic lesions stabilized while others showed progression attenuation compared with that before lenvatinib therapy. Conclusions: These observations suggest that blocking TSHR stimulation with K1-70 can be an effective treatment for GO and may also benefit select patients with FTC and GD.


Assuntos
Adenocarcinoma Folicular/complicações , Adenocarcinoma Folicular/tratamento farmacológico , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/uso terapêutico , Doença de Graves/complicações , Doença de Graves/tratamento farmacológico , Oftalmopatia de Graves/complicações , Oftalmopatia de Graves/tratamento farmacológico , Receptores da Tireotropina/antagonistas & inibidores , Neoplasias da Glândula Tireoide/complicações , Neoplasias da Glândula Tireoide/tratamento farmacológico , Adenocarcinoma Folicular/imunologia , Anticorpos Monoclonais/farmacologia , Antineoplásicos/uso terapêutico , Autoanticorpos/sangue , Feminino , Doença de Graves/imunologia , Oftalmopatia de Graves/imunologia , Humanos , Imunoglobulinas Estimuladoras da Glândula Tireoide/sangue , Radioisótopos do Iodo/uso terapêutico , Pessoa de Meia-Idade , Compostos de Fenilureia/administração & dosagem , Compostos de Fenilureia/uso terapêutico , Quinolinas/administração & dosagem , Quinolinas/uso terapêutico , Compostos Radiofarmacêuticos/uso terapêutico , Receptores da Tireotropina/imunologia , Neoplasias da Glândula Tireoide/imunologia , Resultado do Tratamento
3.
Ecol Evol ; 10(24): 13860-13871, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33391686

RESUMO

Quantitative PCR (qPCR) has been commonly used to measure gene expression in a number of research contexts, but the measured RNA concentrations do not always represent the concentrations of active proteins which they encode. This can be due to transcriptional regulation or post-translational modifications, or localization of immune environments, as can occur during infection. However, in studies using free-living non-model species, such as in ecoimmunological research, qPCR may be the only available option to measure a parameter of interest, and so understanding the quantitative link between gene expression and associated effector protein levels is vital.Here, we use qPCR to measure concentrations of RNA from mesenteric lymph node (MLN) and spleen tissue, and multiplex ELISA of blood serum to measure circulating cytokine concentrations in a wild population of a model species, Mus musculus domesticus.Few significant correlations were found between gene expression levels and circulating cytokines of the same immune genes or proteins, or related functional groups. Where significant correlations were observed, these were most frequently within the measured tissue (i.e., the expression levels of genes measured from spleen tissue were more likely to correlate with each other rather than with genes measured from MLN tissue, or with cytokine concentrations measured from blood).Potential reasons for discrepancies between measures including differences in decay rates and transcriptional regulation networks are discussed. We highlight the relative usefulness of different measures under different research questions and consider what might be inferred from immune assays.

4.
Funct Ecol ; 33(8): 1425-1435, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31588159

RESUMO

The ability, propensity and need to mount an immune response vary both among individuals and within a single individual over time.A wide array of parameters has been found to influence immune state in carefully controlled experiments, but we understand much less about which of these parameters are important in determining immune state in wild populations.Diet can influence immune responses, for example when nutrient availability is limited. We therefore predict that natural dietary variation will play a role in modulating immune state, but this has never been tested.We measured carbon and nitrogen stable isotope ratios in an island population of house mice Mus musculus domesticus as an indication of dietary variation, and the expression of a range of immune-related genes to represent immune state.After accounting for potential confounding influences such as age, sex and helminth load, we found a significant association between carbon isotope ratio and levels of immune activity in the mesenteric lymph nodes, particularly in relation to the inflammatory response.This association demonstrates the important interplay between diet and an animal's response to immune challenges, and therefore potentially its susceptibility to disease. A plain language summary is available for this article.

5.
PLoS One ; 14(9): e0222501, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31557179

RESUMO

The composition of the mammalian gut microbiota can be influenced by a multitude of environmental variables such as diet and infections. Studies investigating the effect of these variables on gut microbiota composition often sample across multiple separate populations and habitat types. In this study we explore how variation in the gut microbiota of the house mouse (Mus musculus domesticus) on the Isle of May, a small island off the east coast of Scotland, is associated with environmental and biological factors. Our study focuses on the effects of environmental variables, specifically trapping location and surrounding vegetation, as well as the host variables sex, age, body weight and endoparasite infection, on the gut microbiota composition across a fine spatial scale in a freely interbreeding population. We found that differences in gut microbiota composition were significantly associated with the trapping location of the host, even across this small spatial scale. Sex of the host showed a weak association with microbiota composition. Whilst sex and location could be identified as playing an important role in the compositional variation of the gut microbiota, 75% of the variation remains unexplained. Whereas other rodent studies have found associations between gut microbiota composition and age of the host or parasite infections, the present study could not clearly establish these associations. We conclude that fine spatial scales are important when considering gut microbiota composition and investigating differences among individuals.


Assuntos
Microbioma Gastrointestinal , Camundongos/microbiologia , Animais , Ecossistema , Meio Ambiente , Feminino , Geografia , Ilhas , Masculino , Escócia
6.
J Mater Chem B ; 7(38): 5742-5761, 2019 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-31531443

RESUMO

Injectable, in situ-forming hydrogels can improve cell delivery in tissue engineering applications by facilitating minimally invasive delivery to irregular defect sites and improving cell retention and survival. Tissues targeted for cell delivery often undergo diverse mechanical loading including high stress, high strain, and repetitive loading conditions. This review focuses on the development of hydrogel systems that meet the requirements of mechanical resiliency, cytocompatibility, and injectability for such applications. First, we describe the most important design considerations for maintaining the viability and function of encapsulated cells, for reproducing the target tissue morphology, and for achieving degradation profiles that facilitate tissue replacement. Models describing the relationships between hydrogel structure and mechanical properties are described, focusing on design principles necessary for producing mechanically resilient hydrogels. The advantages and limitations of current strategies for preparing cytocompatible, injectable, and mechanically resilient hydrogels are reviewed, including double networks, nanocomposites, and high molecular weight amphiphilic copolymer networks. Finally, challenges and opportunities are outlined to guide future research in this developing field.


Assuntos
Hidrogéis/química , Engenharia Tecidual , Materiais Biocompatíveis/química , Sobrevivência Celular/efeitos dos fármacos , Módulo de Elasticidade , Matriz Extracelular/química , Humanos , Hidrogéis/farmacologia , Nanocompostos/química , Polímeros/química
7.
Optom Vis Sci ; 96(4): 266-275, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30907864

RESUMO

SIGNIFICANCE: The pathological changes in clinically significant diabetic macular edema lead to greater retinal thickening in men than in women. Therefore, male sex should be considered a potential risk factor for identifying individuals with the most severe pathological changes. Understanding this excessive retinal thickening in men may help preserve vision. PURPOSE: The purpose of this study was to investigate the sex differences in retinal thickness in diabetic patients. We tested whether men with clinically significant macular edema had even greater central macular thickness than expected from sex differences without significant pathological changes. This study also aimed to determine which retinal layers contribute to abnormal retinal thickness. METHODS: From 2047 underserved adult diabetic patients from Alameda County, CA, 142 patients with clinically significant macular edema were identified by EyePACS-certified graders using color fundus images (Canon CR6-45NM). First, central macular thickness from spectral domain optical coherence tomography (iVue; Optovue Inc.) was compared in 21 men versus 21 women without clinically significant macular edema. Then, a planned comparison contrasted the greater values of central macular thickness in men versus women with clinically significant macular edema as compared with those without. Mean retinal thickness and variability of central macular layers were compared in men versus women. RESULTS: Men without clinically significant macular edema had a 12-µm greater central macular thickness than did women (245 ± 21.3 and 233 ± 13.4 µm, respectively; t40 = -2.18, P = .04). Men with clinically significant macular edema had a 67-µm greater central macular thickness than did women (383 ± 48.7 and 316 ± 60.4 µm, P < .001); that is, men had 55 µm or more than five times more (t20 = 2.35, P = .02). In men, the outer-nuclear-layer thickness was more variable, F10,10 = 9.34. CONCLUSIONS: Underserved diabetic men had thicker retinas than did women, exacerbated by clinically significant macular edema.


Assuntos
Retinopatia Diabética/patologia , Edema Macular/patologia , Retina/patologia , Adulto , Idoso , Diabetes Mellitus , Retinopatia Diabética/diagnóstico por imagem , Feminino , Fundo de Olho , Humanos , Edema Macular/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Fatores Sexuais , Tomografia de Coerência Óptica/métodos
8.
J Mol Endocrinol ; 62(3): 117-128, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30689545

RESUMO

The crystal structures of the thyroid-stimulating hormone receptor (TSHR) leucine-rich repeat domain (amino acids 22-260; TSHR260) in complex with a stimulating human monoclonal autoantibody (M22TM) and in complex with a blocking human autoantibody (K1-70™) have been solved. However, attempts to purify and crystallise free TSHR260, that is not bound to an autoantibody, have been unsuccessful due to the poor stability of free TSHR260. We now describe a TSHR260 mutant that has been stabilised by the introduction of six mutations (H63C, R112P, D143P, D151E, V169R and I253R) to form TSHR260-JMG55TM, which is approximately 900 times more thermostable than wild-type TSHR260. These six mutations did not affect the binding of human TSHR monoclonal autoantibodies or patient serum TSHR autoantibodies to the TSHR260. Furthermore, the response of full-length TSHR to stimulation by TSH or human TSHR monoclonal autoantibodies was not affected by the six mutations. Thermostable TSHR260-JMG55TM has been purified and crystallised without ligand and the structure solved at 2.83 Å resolution. This is the first reported structure of a glycoprotein hormone receptor crystallised without ligand. The unbound TSHR260-JMG55TM structure and the M22 and K1-70 bound TSHR260 structures are remarkably similar except for small changes in side chain conformations. This suggests that neither the mutations nor the binding of M22TM or K1-70TM change the rigid leucine-rich repeat domain structure of TSHR260. The solved TSHR260-JMG55TM structure provides a rationale as to why the six mutations have a thermostabilising effect and provides helpful guidelines for thermostabilisation strategies of other soluble protein domains.


Assuntos
Cristalografia por Raios X/métodos , Leucina/química , Proteínas/metabolismo , Receptores da Tireotropina/sangue , Receptores da Tireotropina/química , Autoanticorpos/sangue , Humanos , Proteínas de Repetições Ricas em Leucina , Mutação/genética , Domínios Proteicos , Proteínas/química , Proteínas/genética , Receptores Acoplados a Proteínas G/sangue , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/genética , Receptores da Tireotropina/genética
9.
Clin Endocrinol (Oxf) ; 90(2): 369-374, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30485487

RESUMO

OBJECTIVE: TSH receptor antibodies (TRAb) are responsible for autoimmune hyperthyroid disease (Graves' disease; GD) with TRAb levels tending to decrease following treatment. Measurement of TRAb activity during follow-up could prove valuable to better understand treatment effectiveness. STUDY DESIGN: TRAb concentration and stimulating (TSAb) and blocking (TSBAb) activity of patient serum were assessed following different treatment modalities and follow-up length. METHODS: Sixty-six subjects were recruited following treatment with carbimazole (n = 26), radioiodine (n = 27) or surgery (n = 13). TRAb, TPOAb, TgAb and GADAb were measured at a follow-up visit as well as bioassays of TSAb and TSBAb activity. RESULTS: Forty-five per cent of all patients remained TRAb-positive for more than one year and 23% for more than 5 years after diagnosis, irrespective of treatment method. Overall, TRAb concentration fell from a median (IQR) of 6.25 (3.9-12.7) to 0.65 (0.38-3.2) U/L. Surgery conferred the largest fall in TRAb concentration from 11.4 (6.7-29) to 0.58 (0.4-1.4) U/L. Seventy per cent of TRAb-positive patients were positive for TSAb, and one patient (3%) was positive for TSBAb. TRAb and TSAb correlated well (r = 0.83). In addition, 38/66 patients were TgAb-positive, 47/66 were TPOAb-positive and 6/66 were GADAb-positive at follow-up. CONCLUSIONS: TRAb levels generally decreased after treatment but persisted for over 5 years in some patients. TRAb activity was predominantly stimulatory, with only one patient demonstrating TSBAb. A large proportion of patients were TgAb/TPOAb-positive at follow-up. All treatment modalities reduced TRAb concentrations; however, surgery was most effective.


Assuntos
Autoanticorpos/sangue , Doença de Graves/terapia , Receptores da Tireotropina/imunologia , Adulto , Carbimazol/uso terapêutico , Feminino , Doença de Graves/etiologia , Doença de Graves/imunologia , Doença de Graves/cirurgia , Humanos , Radioisótopos do Iodo/uso terapêutico , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
10.
J Biomed Mater Res A ; 107(3): 571-585, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30390406

RESUMO

Cell-based therapies involving the injection of adipose-derived stem/stromal cells (ASCs) within rationally designed biomaterials are a promising approach for stimulating angiogenesis. With this focus, the current work explored the effects of incorporating integrin-binding RGD or IKVAV peptides within in situ-gelling N-methacrylate glycol chitosan (MGC) hydrogels on the response of encapsulated human ASCs. Initial studies focused on hydrogel characterization to validate that the MGC, MGC-RGD, and MGC-IKVAV hydrogels had similar biomechanical properties. ASC viability following encapsulation and culture under 2% O2 was significantly impaired in the MGC-IKVAV group relative to the MGC and MGC-RGD groups. In contrast, sustained viability, along with enhanced cell spreading and metabolic activity were observed in the MGC-RGD group. Investigation of angiogenic transcription suggested that the incorporation of the peptide groups did not substantially alter the pro-angiogenic gene expression profile of the encapsulated ASCs after 7 days of culture under 2% O2. Consistent with the in vitro findings, preliminary in vivo characterization following subcutaneous implantation into NOD/SCID mice showed that ASC retention was enhanced in the MGC-RGD hydrogels relative to the MGC-IKVAV group at 14 days. Further, the encapsulated ASCs in the MGC and MGC-RGD groups promoted murine CD31+ endothelial cell recruitment to the peri-implant region. Overall, the results indicate that the MGC-RGD and MGC hydrogels are promising platforms for ASC delivery, and suggest that strategies that support long-term ASC viability can augment in vivo angiogenesis through paracrine mechanisms. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 571-585, 2019.


Assuntos
Tecido Adiposo/metabolismo , Células Imobilizadas , Quitosana , Hidrogéis , Neovascularização Fisiológica , Oligopeptídeos , Transplante de Células-Tronco , Células-Tronco/metabolismo , Tecido Adiposo/citologia , Animais , Sobrevivência Celular , Células Imobilizadas/citologia , Células Imobilizadas/metabolismo , Células Imobilizadas/transplante , Quitosana/química , Quitosana/farmacologia , Xenoenxertos , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Oligopeptídeos/química , Oligopeptídeos/farmacologia , Células-Tronco/citologia
11.
Ecol Evol ; 8(19): 9947-9957, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30386588

RESUMO

Improving technology and increasing affordability mean that camera trapping-the use of remotely triggered cameras to photograph wildlife-is becoming an increasingly common tool in the monitoring and conservation of wild populations. Each camera trap study generates a vast amount of data, which need to be processed and labeled before analysis. Traditionally, processing camera trap data has been performed manually by entering data into a spreadsheet. This is time-consuming, prone to human error, and data management may be inconsistent between projects, hindering collaboration. Recently, several programs have become available to facilitate and quicken data processing. Here, we review available software and assess their ability to better standardize camera trap data management and facilitate data sharing and collaboration. To identify available software for camera trap data management, we used internet searches and contacted researchers and practitioners working on large camera trap projects, as well as software developers. We tested all available programs against a range of software characteristics in addition to their ability to record a suite of important data variables extracted from images. We identified and reviewed 12 available programs for the management of camera trap data. These ranged from simple software assisting with the extraction of metadata from an image, through to comprehensive programs that facilitate data entry and analysis. Many of the programs tested were developed for use on specific studies and so do not cover all possible software or data collection requirements that different projects may have. We highlight the importance of a standardized software solution for camera trap data management. This approach would allow all possible data to be collected, enabling researchers to share data and contribute to other studies, as well as facilitating multi-project comparisons. By standardizing camera trap data collection and management in this way, future studies would be better placed to guide conservation policy on a global level.

12.
J Phys Chem A ; 122(25): 5656-5665, 2018 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-29870255

RESUMO

The continued demand for gas-phase molecular structures has led to the recommissioning of a gas electron diffractometer, formerly housed at the University of Reading. The gas electron diffractometer, now the only one of its kind in the U.K., is currently housed at the University of York, where it is now used routinely to determine directly structures of isolated molecules in the gas phase. The instrument has been fitted with an air-heated nozzle assembly to increase the range of molecules accessible to study in the gas phase; the efficacy of this assembly is demonstrated in this article via the determination of the gas-phase structure of 4-(dimethylamino)benzonitrile (DMABN) at high temperature. A series of complementary theoretical calculations using the B2PLYP DFT functional of Grimme et al. with correlation-consistent basis sets of double, triple, and quadruple-ζ quality are also presented. The agreement between the experimental and theoretical structural parameters attests to the accuracy of the applied theoretical calculations and of our gas-phase structural solution.

13.
Tissue Eng Part A ; 24(23-24): 1784-1797, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29882474

RESUMO

Injectable hydrogels have the potential to enhance stem cell-based therapies by improving cell localization, retention, and survival after transplantation. The inflammatory response to both the hydrogel and the encapsulated cells is a critical aspect of this strategy, with macrophages being highly involved in the process of hydrogel remodeling, angiogenesis, and tissue regeneration. As a step toward the development of a cell-based strategy for therapeutic angiogenesis, this work compared the intramuscular injection of allogeneic rat adipose-derived stem/stromal cells (rASCs) in an in situ gelling hydrogel with the injection of the hydrogel alone and rASCs in saline in an immunocompetent rat model by immunohistochemical analysis over 4 weeks. rASCs delivered in the hydrogel were retained intramuscularly at significantly higher densities as compared with cells delivered in saline. The encapsulated rASCs modulated the inflammatory response, promoting CD68+ macrophage recruitment, with the majority of infiltrating cells expressing the M1 marker CCR7, as well as a higher fraction of CD163+ M2c macrophages surrounding the hydrogel. Furthermore, rASCs reduced the initial expression of inducible nitric oxide synthase and promoted arginase-1 expression in the infiltrating macrophages over time, consistent with a shift toward a more proregenerative phenotype. Coincident with the enhanced macrophage infiltration, significantly more CD31+ lumens were observed surrounding and within the hydrogels with rASCs at 2 and 4 weeks as compared with the hydrogels alone. Overall, these results are a promising indication that encapsulated rASCs can have immunomodulatory effects and may enhance angiogenic processes after intramuscular injection, promoting a regenerative macrophage response and blood vessel formation.


Assuntos
Adipócitos/metabolismo , Diferenciação Celular , Hidrogéis , Macrófagos/metabolismo , Transplante de Células-Tronco , Células-Tronco/metabolismo , Adipócitos/citologia , Animais , Células Imobilizadas/citologia , Células Imobilizadas/metabolismo , Células Imobilizadas/transplante , Feminino , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Ratos , Ratos Wistar , Células-Tronco/citologia
14.
Biomaterials ; 159: 146-160, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29324306

RESUMO

A promising strategy for treating peripheral ischemia involves the delivery of stem cells to promote angiogenesis through paracrine signaling. Treatment success depends on cell localization, retention, and survival within the mechanically dynamic intramuscular (IM) environment. Herein we describe an injectable, in situ-gelling hydrogel for the IM delivery of adipose-derived stem/stromal cells (ASCs), specifically designed to withstand the dynamic loading conditions of the lower limb and facilitate cytokine release from encapsulated cells. Copolymers of poly(trimethylene carbonate)-b-poly(ethylene glycol)-b-poly(trimethylene carbonate) diacrylate were used to modulate the properties of methacrylated glycol chitosan hydrogels crosslinked by thermally-initiated polymerization using ammonium persulfate and N,N,N',N'-tetramethylethylenediamine. The scaffolds had an ultimate compressive strain over 75% and maintained mechanical properties during compressive fatigue testing at physiological levels. Rapid crosslinking (<3 min) was achieved at low initiator concentration (5 mM). Following injection and crosslinking within the scaffolds, human ASCs demonstrated high viability (>90%) over two weeks in culture under both normoxia and hypoxia. Release of angiogenic and chemotactic cytokines was enhanced from encapsulated cells under sustained hypoxia, in comparison to normoxic and tissue culture polystyrene controls. When delivered by IM injection in a mouse model of hindlimb ischemia, human ASCs were well retained in the scaffold over 28 days and significantly increased the IM vascular density compared to untreated controls.


Assuntos
Citocinas/metabolismo , Células-Tronco/metabolismo , Tecidos Suporte/química , Tecido Adiposo/citologia , Animais , Células Cultivadas , Feminino , Humanos , Hidrogéis/química , Imuno-Histoquímica , Camundongos , Doença Arterial Periférica/metabolismo , Engenharia Tecidual/métodos
15.
Atmos Meas Tech ; 11(3): 1459-1479, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33479568

RESUMO

Data products from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) on board Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) were recently updated following the implementation of new (version 4) calibration algorithms for all of the level 1 attenuated backscatter measurements. In this work we present the motivation for and the implementation of the version 4 nighttime 532 nm parallel channel calibration. The nighttime 532 nm calibration is the most fundamental calibration of CALIOP data, since all of CALIOP's other radiometric calibration procedures - i.e., the 532 nm daytime calibration and the 1064 nm calibrations during both nighttime and daytime - depend either directly or indirectly on the 532 nm nighttime calibration. The accuracy of the 532 nm nighttime calibration has been significantly improved by raising the molecular normalization altitude from 30-34 km to 36-39 km to substantially reduce stratospheric aerosol contamination. Due to the greatly reduced molecular number density and consequently reduced signal-to-noise ratio (SNR) at these higher altitudes, the signal is now averaged over a larger number of samples using data from multiple adjacent granules. As well, an enhanced strategy for filtering the radiation-induced noise from high energy particles was adopted. Further, the meteorological model used in the earlier versions has been replaced by the improved MERRA-2 model. An aerosol scattering ratio of 1.01 ± 0.01 is now explicitly used for the calibration altitude. These modifications lead to globally revised calibration coefficients which are, on average, 2-3% lower than in previous data releases. Further, the new calibration procedure is shown to eliminate biases at high altitudes that were present in earlier versions and consequently leads to an improved representation of stratospheric aerosols. Validation results using airborne lidar measurements are also presented. Biases relative to collocated measurements acquired by the Langley Research Center (LaRC) airborne high spectral resolution lidar (HSRL) are reduced from 3.6% ± 2.2% in the version 3 data set to 1.6% ± 2.4 % in the version 4 release.

16.
Atmos Meas Tech ; 11(7): 4129-4152, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33510819

RESUMO

The CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations) level 3 aerosol profile product reports globally gridded, quality-screened, monthly mean aerosol extinction profiles retrieved by CALIOP (the Cloud-Aerosol Lidar with Orthogonal Polarization). This paper describes the quality screening and averaging methods used to generate the version 3 product. The fundamental input data are CALIOP level 2 aerosol extinction profiles and layer classification information (aerosol, cloud, and clear-air). Prior to aggregation, the extinction profiles are quality-screened by a series of filters to reduce the impact of layer detection errors, layer classification errors, extinction retrieval errors, and biases due to an intermittent signal anomaly at the surface. The relative influence of these filters are compared in terms of sample rejection frequency, mean extinction, and mean aerosol optical depth (AOD). The "extinction QC flag" filter is the most influential in preventing high-biases in level 3 mean extinction, while the "misclassified cirrus fringe" filter is most aggressive at rejecting cirrus misclassified as aerosol. The impact of quality screening on monthly mean aerosol extinction is investigated globally and regionally. After applying quality filters, the level 3 algorithm calculates monthly mean AOD by vertically integrating the monthly mean quality-screened aerosol extinction profile. Calculating monthly mean AOD by integrating the monthly mean extinction profile prevents a low bias that would result from alternately integrating the set of extinction profiles first and then averaging the resultant AOD values together. Ultimately, the quality filters reduce level 3 mean AOD by -24 and -31% for global ocean and global land, respectively, indicating the importance of quality screening.

17.
Macromol Biosci ; 17(5)2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28085994

RESUMO

Cell-based therapies have great potential to regenerate and repair injured articular cartilage, and a range of synthetic and natural polymer-based hydrogels have been used in combination with stem cells and growth factors for this purpose. Although the hydrogel scaffolds developed to date possess many favorable characteristics, achieving the required mechanical properties has remained a challenge. A hydrogel system with tunable mechanical properties, composed of a mixture of natural and synthetic polymers, and its use for the encapsulation of adipose derived stem/stromal cells (ASCs) is described. Solutions of methacrylated chondroitin sulfate (MCS) are mixed with solutions of acrylate-poly(trimethylene carbonate)-b-poly(ethylene glycol)-b-poly(trimethylene carbonate)-acrylate (PEG-(PTMC-A)2 ) in phosphate buffered saline and crosslinked via thermally initiated free radical polymerization. The hydrogel compressive equilibrium moduli and toughness are readily tailored by varying the concentration of the pre-polymers, as well as the molecular weight of the PEG used to prepare the PEG-(PTMC-A)2 . Two peptide sequences, GVOGEA and GGGGRGDS, are individually conjugated to the MCS to facilitate cell binding. The presence of the peptide ligands yields high ASC viability and long term metabolic activity following encapsulation in hydrogels prepared using the thermal initiator system. Overall, these hydrogels show promise as a minimally invasive ASC delivery strategy for chondral defect repair.


Assuntos
Adipócitos/citologia , Cartilagem Articular/patologia , Hidrogéis , Células-Tronco/citologia , Animais , Bovinos , Células Cultivadas , Engenharia Tecidual
18.
Optom Vis Sci ; 94(2): 137-149, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27846063

RESUMO

PURPOSE: To investigate whether cysts in diabetic macular edema are better visualized in the red channel of color fundus camera images, as compared with the green channel, because color fundus camera screening methods that emphasize short-wavelength light may miss cysts in patients with dark fundi or changes to outer blood retinal barrier. METHODS: Fundus images for diabetic retinopathy photoscreening were acquired for a study with Aeon Imaging, EyePACS, University of California Berkeley, and Indiana University. There were 2047 underserved, adult diabetic patients, of whom over 90% self-identified as a racial/ethnic identify other than non-Hispanic white. Color fundus images at nominally 45 degrees were acquired with a Canon Cr-DGi non-mydriatic camera (Tokyo, Japan) then graded by an EyePACS certified grader. From the 148 patients graded to have clinically significant macular edema by the presence of hard exudates in the central 1500 µm of the fovea, we evaluated macular cysts in 13 patients with cystoid macular edema. Age ranged from 33 to 68 years. Color fundus images were split into red, green, and blue channels with custom Matlab software (Mathworks, Natick, MA). The diameter of a cyst or confluent cysts was quantified in the red-channel and green-channel images separately. RESULTS: Cyst identification gave complete agreement between red-channel images and the standard full-color images. This was not the case for green-channel images, which did not expose cysts visible with standard full-color images in five cases, who had dark fundi. Cysts appeared more numerous and covered a larger area in the red channel (733 ± 604 µm) than in the green channel (349 ± 433 µm, P < .006). CONCLUSIONS: Cysts may be underdetected with the present fundus camera methods, particularly when short-wavelength light is emphasized or in patients with dark fundi. Longer wavelength techniques may improve the detection of cysts and provide more information concerning the early stages of diabetic macular edema or the outer blood retinal barrier.


Assuntos
Cistos/diagnóstico , Retinopatia Diabética/diagnóstico , Angiofluoresceinografia/métodos , Edema Macular/diagnóstico , Adulto , Idoso , Cistos/complicações , Retinopatia Diabética/complicações , Feminino , Fundo de Olho , Humanos , Edema Macular/etiologia , Masculino , Pessoa de Meia-Idade , Fotografação/métodos , Estudos Prospectivos
19.
PLoS Comput Biol ; 12(9): e1005106, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27684554

RESUMO

While it is known that musculotendon units adapt to their load environments, there is only a limited understanding of tendon adaptation in vivo. Here we develop a computational model of tendon remodeling based on the premise that mechanical damage and tenocyte-mediated tendon damage and repair processes modify the distribution of its collagen fiber lengths. We explain how these processes enable the tendon to geometrically adapt to its load conditions. Based on known biological processes, mechanical and strain-dependent proteolytic fiber damage are incorporated into our tendon model. Using a stochastic model of fiber repair, it is assumed that mechanically damaged fibers are repaired longer, whereas proteolytically damaged fibers are repaired shorter, relative to their pre-damage length. To study adaptation of tendon properties to applied load, our model musculotendon unit is a simplified three-component Hill-type model of the human Achilles-soleus unit. Our model results demonstrate that the geometric equilibrium state of the Achilles tendon can coincide with minimization of the total metabolic cost of muscle activation. The proposed tendon model independently predicts rates of collagen fiber turnover that are in general agreement with in vivo experimental measurements. While the computational model here only represents a first step in a new approach to understanding the complex process of tendon remodeling in vivo, given these findings, it appears likely that the proposed framework may itself provide a useful theoretical foundation for developing valuable qualitative and quantitative insights into tendon physiology and pathology.

20.
Vet Microbiol ; 179(3-4): 315-21, 2015 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-26130518

RESUMO

The condition known as spotty liver disease or spotty liver syndrome can cause significant mortality in free range laying hen flocks. It has been described in Europe and Australia but the aetiology has not been established. There are similarities between spotty liver disease and avian vibrionic hepatitis, a condition which was reported in the 1950s. A Vibrio-like organism was suspected to be the cause of avian vibrionic hepatitis, although this organism was never fully characterised. We report the isolation of a novel Campylobacter from five separate outbreaks of spotty liver disease. The conditions required for culture, the growth characteristics, electron microscopical morphology and results of the phenotypic tests used in the identification of this novel Campylobacter sp. are described. The novel Campylobacter is slow growing and fastidious and does not grow on media routinely used for isolating Campylobacter sp. The morphology is typical for a Campylobacter sp. and phenotypic tests and a duplex real time PCR test differentiate the novel Campylobacter from other members of the genus. 16S rRNA analysis of 19 isolates showed an identical sequence which appears to represent a hitherto unknown sub lineage within the genus Campylobacter. Experimental intraperitoneal infection of four week old SPF chickens produced microscopic liver pathology indistinguishable from natural disease and the novel Campylobacter was recovered from the experimentally infected chicks. The isolates described appear to be a possible causal organism for spotty liver disease.


Assuntos
Infecções por Campylobacter/veterinária , Campylobacter/classificação , Hepatopatias/veterinária , Doenças das Aves Domésticas/microbiologia , Animais , Austrália , Campylobacter/isolamento & purificação , Infecções por Campylobacter/microbiologia , Galinhas , Europa (Continente) , Feminino , Hepatopatias/microbiologia , RNA Bacteriano/genética , RNA Ribossômico 16S , Reprodução
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