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1.
Plants (Basel) ; 12(17)2023 Aug 28.
Article in English | MEDLINE | ID: mdl-37687332

ABSTRACT

The floras on the highest mountains in tropical eastern Africa are among the most unique floras in the world. Despite the exceptionally high concentration of endemic species, these floras remain understudied from an evolutionary point of view. In this study, we focus on the Carduus-Cirsium group (subtribe Carduinae) to unravel the evolutionary relationships of the species endemic to the tropical Afromontane and Afroalpine floras, aiming to improve the systematics of the group. We applied the Hyb-Seq approach using the Compositae1061 probe set on 190 samples (159 species), encompassing representatives of all genera of Carduinae. We used two recently developed pipelines that enabled the processing of raw sequence reads, identification of paralogous sequences and segregation into orthologous alignments. After the implementation of a missing data filter, we retained sequences from 986 nuclear loci and 177 plastid regions. Phylogenomic analyses were conducted using both concatenated and summary-coalescence methods. The resulting phylogenies were highly resolved and revealed three distinct evolutionary lineages consisting of the African species traditionally referred to as Carduus and Cirsium. Consequently, we propose the three new genera Afrocarduus, Afrocirsium and Nuriaea; the latter did notably not belong to the Carduus-Cirsium group. We detected some incongruences between the phylogenies based on concatenation vs. coalescence and on nuclear vs. plastid datasets, likely attributable to incomplete lineage sorting and/or hybridization.

2.
Mol Phylogenet Evol ; 189: 107928, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37714444

ABSTRACT

The Irano-Turanian region is one of the world's richest floristic regions and the centre of diversity for numerous xerophytic plant lineages. However, we still have limited knowledge on the timing of evolution and biogeographic history of its flora, and potential drivers of diversification remain underexplored. To fill this knowledge gap, we focus on the Eurasian genus Jurinea (ca. 200 species), one of the largest plant radiations that diversified in the region. We applied a macroevolutionary integrative approach to explicitly test diversification hypotheses and investigate the relative roles of geography vs. ecology and niche conservatism vs. niche lability in speciation processes. To do so, we gathered a sample comprising 77% of total genus richness and obtained data about (1) its phylogenetic history, recovering 502 nuclear loci sequences; (2) growth forms; (3) ecological niche, compiling data of 21 variables for more than 2500 occurrences; and (4) paleoclimatic conditions, to estimate climatic stability. Our results revealed that climate was a key factor in the evolutionary dynamics of Jurinea. The main diversification and biogeographic events that occurred during past climate changes, which led to colder and drier conditions, are the following: (1) the origin of the genus (10.7 Ma); (2) long-distance dispersals from the Iranian Plateau to adjacent regions (∼7-4 Ma); and (3) the diversification shift during Pliocene-Pleistocene Transition (ca. 3 Ma), when net diversification rate almost doubled. Our results supported the pre-adaptation hypothesis, i.e., the evolutionary success of Jurinea was linked to the retention of the ancestral niche adapted to aridity. Interestingly, the paleoclimatic analyses revealed that in the Iranian Plateau long-term climatic stability favoured old-lineage persistence, resulting in current high species richness of semi-arid and cold adapted clades; whereas moderate climate oscillations stimulated allopatric diversification in the lineages distributed in the Circumboreal region. In contrast, growth form lability and high niche disparity among closely related species in the Central Asian clade suggest adaptive radiation to mountain habitats. In sum, the radiation of Jurinea is the result of both adaptive and non-adaptive processes influenced by climatic, orogenic and ecological factors.


Subject(s)
Asteraceae , Biological Evolution , Phylogeny , Iran , Phylogeography
3.
Plants (Basel) ; 12(11)2023 Jun 03.
Article in English | MEDLINE | ID: mdl-37299192

ABSTRACT

The Afromontane and Afroalpine areas constitute some of the main biodiversity hotspots of Africa. They are particularly rich in plant endemics, but the biogeographic origins and evolutionary processes leading to this outstanding diversity are poorly understood. We performed phylogenomic and biogeographic analyses of one of the most species-rich plant genera in these mountains, Helichrysum (Compositae-Gnaphalieae). Most previous studies have focused on Afroalpine elements of Eurasian origin, and the southern African origin of Helichrysum provides an interesting counterexample. We obtained a comprehensive nuclear dataset from 304 species (≈50% of the genus) using target-enrichment with the Compositae1061 probe set. Summary-coalescent and concatenation approaches combined with paralog recovery yielded congruent, well-resolved phylogenies. Ancestral range estimations revealed that Helichrysum originated in arid southern Africa, whereas the southern African grasslands were the source of most lineages that dispersed within and outside Africa. Colonization of the tropical Afromontane and Afroalpine areas occurred repeatedly throughout the Miocene-Pliocene. This timing coincides with mountain uplift and the onset of glacial cycles, which together may have facilitated both speciation and intermountain gene flow, contributing to the evolution of the Afroalpine flora.

4.
J Microbiol Immunol Infect ; 56(5): 939-950, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37365052

ABSTRACT

BACKGROUND/PURPOSE(S): During a viral infection, the immune response is mediated by the toll-like receptors and myeloid differentiation Factor 88 (MyD88) that play an important role sensing infections such as SARS-CoV-2 which has claimed the lives of more than 6.8 million people around the world. METHODS: We carried out a cross-sectional with a population of 618 SARS-CoV-2-positive unvaccinated subjects and further classified based on severity: 22% were mild, 34% were severe, 26% were critical, and 18% were deceased. Toll Like Receptor 7 (TLR7) single-nucleotide polymorphisms (rs3853839, rs179008, rs179009, and rs2302267) and MyD88 (rs7744) were genotyped using TaqMan OpenArray. The association of polymorphisms with disease outcomes was performed by logistic regression analysis adjusted by covariates. RESULTS: A significant association of rs3853839 and rs7744 of the TLR7 and MyD88 genes, respectively, was found with COVID-19 severity. The G/G genotype of the rs3853839 TLR7 was associated with the critical outcome showing an Odd Ratio = 1.98 (95% IC = 1.04-3.77). The results highlighted an association of the G allele of MyD88 gene with severe, critical and deceased outcomes. Furthermore, in the dominant model (AG + GG vs. AA), we observed an Odd Ratio = 1.70 (95% CI = 1.02-2.86) with severe, Odd Ratio = 1.82 (95% CI = 1.04-3.21) with critical, and Odd Ratio = 2.44 (95% CI = 1.21-4.9) with deceased outcomes. CONCLUSION: To our knowledge this work represents an innovative report that highlights the significant association of TLR7 and MyD88 gene polymorphisms with COVID-19 outcomes and the possible implication of the MyD88 variant with D-dimer and IFN-α concentrations.


Subject(s)
COVID-19 , Toll-Like Receptor 7 , Humans , Toll-Like Receptor 7/genetics , Toll-Like Receptor 7/metabolism , Genetic Predisposition to Disease , Myeloid Differentiation Factor 88/genetics , Cross-Sectional Studies , COVID-19/genetics , SARS-CoV-2 , Genotype , Polymorphism, Single Nucleotide/genetics
5.
J Occup Environ Med ; 64(11): 934-941, 2022 11 01.
Article in English | MEDLINE | ID: mdl-35959912

ABSTRACT

OBJECTIVE: To determine to what extent did health care workers experience the pandemic as a severe stress event. METHODS: This cross-sectional evaluation of 8299 health care workers, representing a 22% response rate, utilized machine learning to predict high levels of escalating stress based on demographics and known predictors for adverse psychological outcomes after trauma. RESULTS: A third of health care workers experienced the pandemic as a potentially traumatic stress event; a greater proportion of health care workers experienced high levels of escalating stress. Predictive factors included sense of control, ability to manage work-life demands, guilt or shame, age, and level of education. Gender was no longer predictive after controlling for other factors. Escalating stress was especially high among nonclinical academics and clinical private practitioners. CONCLUSION: Findings suggest adverse effects on total worker health, care quality, professionalism, retention, and acute and chronic mental health.


Subject(s)
COVID-19 , Disasters , Stress Disorders, Post-Traumatic , Humans , COVID-19/epidemiology , Cross-Sectional Studies , Self-Assessment , Stress Disorders, Post-Traumatic/epidemiology , Stress Disorders, Post-Traumatic/psychology , Health Personnel/psychology
6.
Plants (Basel) ; 11(12)2022 Jun 15.
Article in English | MEDLINE | ID: mdl-35736734

ABSTRACT

Preserving biodiversity at the global and local scales is a challenge for the future decades, both for protecting species and habitats and to enhance the ecosystem services they provide to the human population [...].

7.
Más Vita ; 4(2): 293-303, jun. 2022. tab
Article in Spanish | LILACS, LIVECS | ID: biblio-1392284

ABSTRACT

La insuficiencia renal crónica afecta a toda una población adulta e influye en su calidad de vida. En el Ecuador se reporta que más del 65% de pacientes con hipertensión y diabetes progresan con insuficiencia renal. Objetivo: Validar los instrumentos para evaluar la influencia de la hemodiálisis en la calidad de vida del adulto mayor con insuficiencia renal crónica, Unidad Dialysis Center. Materiales y métodos: La investigación tuvo un enfoque cuali-cuantitativo, diseño no experimental, descriptivo de corte transversal. Se realizó una prueba piloto con los instrumentos a validarse en una muestra conformada por 15 adultos mayores que se encuentran en tratamiento sustitutivo de hemodiálisis. Resultados: El instrumento cuantitativo o encuesta obtuvo un coeficiente de confiabilidad (Alfa de Cronbach) de 0.80 y la entrevista o instrumento cualitativo, una puntuación de 95 según la rúbrica de los expertos, por lo que los instrumentos fueron aprobados y es confiable su aplicación para responder a los objetivos planteados en la investigación. Conclusiones: Con los resultados obtenidos por el plan piloto realizado, se identifica una influencia considerable de la insuficiencia renal crónica en la calidad de vida, comprende repercusiones a nivel emocional desarrollando depresión. Los datos obtenidos validan la efectividad de los instrumentos para el estudio(AU)


Chronic renal failure affects an entire adult population and influences their quality of life. In Ecuador it is reported that more than 65% of patients with hypertension and diabetes progress to kidney failure. Objective: To validate the instruments to evaluate the influence of hemodialysis on the quality of life of the elderly with chronic renal failure, Dialysis Center Unit. Materials and methods: The research had a qualitative-quantitative approach, non-experimental, descriptive cross-sectional design. A pilot test was carried out with the instruments to be validated in a sample made up of 15 older adults who are on hemodialysis replacement therapy. Results: The quantitative instrument or survey obtained a reliability coefficient (Cronbach's Alpha) of 0.80 and the interview or qualitative instrument, a score of 95 according to the experts' rubric, so the instruments were approved and their application is reliable for respond to the objectives set out in the research. Conclusions: With the results obtained by the pilot plan carried out, a considerable influence of chronic renal failure on quality of life is identified, including repercussions at an emotional level, developing depression. The data obtained validate the effectiveness of the instruments for the study(AU)


Subject(s)
Humans , Male , Female , Aged , Aged, 80 and over , Quality of Life , Aged , Renal Dialysis , Renal Insufficiency, Chronic , Chronic Disease , Surveys and Questionnaires , Mood Disorders , Diabetes Mellitus , Hypertension
8.
PhytoKeys ; 195: 143-160, 2022.
Article in English | MEDLINE | ID: mdl-36761355

ABSTRACT

Sileneneglecta has been misunderstood and confused with S.nocturna, although several morphological characters (petal shape, calyx indumentum, hairiness of stamen filaments, seed size, seed-coat surface and shape) allow separation of these species. Moreover, S.mutabilis (which has been considered conspecific with S.neglecta) and S.martinolii (an alleged endemic species to south-western Sardinia) are considered here as taxonomic synonyms of S.nocturna and S.neglecta, respectively. These taxonomic conclusions are strongly supported by multivariate morphometric analyses of 21 characters.

9.
Cureus ; 13(7): e16521, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34306902

ABSTRACT

On radiographic imaging, the finding of a right-sided heart location can be due to multiple etiologies and may be congenital or acquired. We present the case of a 71-year-old male with a self-reported past medical history of hiatal hernia and previously diagnosed dextrocardia. The patient experienced cardiovascular intervention following an ST-elevation myocardial infarction. In the cardiac workup, a low-voltage normal electrocardiogram confirmed dextroposition of the heart due to significant herniation of gastric contents into the thoracic cavity. This gentleman had presumably been diagnosed with dextrocardia, a right-left reversal of heart anatomy and electrophysiology, based on imaging and incomplete workup. Dextroposition refers to a rightward shift of the mediastinum with no changes in orientation of cardiac anatomy, and therefore unchanged directional orientation of conduction. This is an important distinction from dextrocardia, a mirror-image reversal of the cardiac chambers and heart location in the chest wall, such as that due to congenital ciliary dysfunction. A sliding hernia is an uncommon cause of the rightward mediastinal shift, with few such cases documented in the literature, and cardiovascular manifestations of hiatal hernias are discussed. This case exemplifies the role of an electrocardiogram in distinguishing between dextrocardia and dextroposition for accurate diagnosis and management.

10.
Nano Lett ; 21(3): 1352-1359, 2021 02 10.
Article in English | MEDLINE | ID: mdl-33508203

ABSTRACT

Microbes are critical drivers of all ecosystems and many biogeochemical processes, yet little is known about how the three-dimensional (3D) organization of these dynamic organisms contributes to their overall function. To probe how biofilm structure affects microbial activity, we developed a technique for patterning microbes in 3D geometries using projection stereolithography to bioprint microbes within hydrogel architectures. Bacteria were printed and monitored for biomass accumulation, demonstrating postprint viability of cells using this technique. We verified our ability to integrate biological and geometric complexity by fabricating a printed biofilm with two E. coli strains expressing different fluorescence. Finally, we examined the target application of microbial absorption of metal ions to investigate geometric effects on both the metal sequestration efficiency and the uranium sensing capability of patterned engineered Caulobacter crescentus strains. This work represents the first demonstration of the stereolithographic printing of microbials and presents opportunities for future work of engineered biofilms and other complex 3D structured cultures.


Subject(s)
Bioprinting , Biofilms , Ecosystem , Escherichia coli/genetics , Printing, Three-Dimensional
11.
Gen Hosp Psychiatry ; 68: 12-18, 2021.
Article in English | MEDLINE | ID: mdl-33254081

ABSTRACT

The burden of the COVID-19 pandemic upon healthcare workers necessitates a systematic effort to support their resilience. This article describes the Yale University and Yale New Haven Health System effort to unite several independent initiatives into a coherent integrated model for institutional support for healthcare workers. Here, we highlight both opportunities and challenges faced in attempting to support healthcare workers during this pandemic.


Subject(s)
Academic Medical Centers/organization & administration , Behavioral Symptoms/therapy , COVID-19 , Mindfulness/organization & administration , Occupational Stress/therapy , Personnel, Hospital/psychology , Psychosocial Intervention/organization & administration , Resilience, Psychological , Social Support , Adult , Female , Humans , Male , Middle Aged
12.
Cell Mol Bioeng ; 13(5): 527-540, 2020 Oct.
Article in English | MEDLINE | ID: mdl-33184581

ABSTRACT

INTRODUCTION: The biological and mechanical properties of circulating tumor cells (CTCs) in combination with the hemodynamics affect the preference of metastatic sites in the vasculature. Despite the extensive literature on the effects of biological properties on cell adhesion, the effects of hydrodynamic forces on primary attachment remains an active area of research. Using simulations in conjunction with experimentation, we provide new insight into the interplay of CTCs dynamics and local hydrodynamics. METHODS: A flow experiment of CTC attachment was performed within a bioprinted, double branching endothelialized vessel. Simulations of fluid flow and CTC transport in the reconstructed and idealized bifurcated vessel were respectively performed by HARVEY, our in-house massively parallel computational fluid dynamics solver. HARVEY is based on the lattice Boltzmann and finite element methods to model the fluid and cells dynamics. The immersed boundary method is employed for resolving the fluid-structure interaction. RESULTS: CTC attachment was quantified experimentally at all regions of the complex vessel. The results demonstrate a clear preference for CTCs to attach at the branch points. To elucidate the effect of the vessel topology on the location of attachment, a fluid-only simulation was performed assessing the differences in the hydrodynamics along the vessel. CTC transport in idealized bifurcated vessels was subsequently studied to examine the effects of cell deformability on the local hydrodynamics patterns and, thus, the preference of attachment sites. CONCLUSIONS: The current work provides evidence on the correlation of the hydrodynamics forces arising from the vessel topology and CTC properties on the attachment regions.

13.
Biofabrication ; 13(1)2020 10 16.
Article in English | MEDLINE | ID: mdl-32977323

ABSTRACT

Various types of embolization devices have been developed for the treatment of cerebral aneurysms. However, it is challenging to properly evaluate device performance and train medical personnel for device deployment without the aid of functionally relevant models. Currentin vitroaneurysm models suffer from a lack of key functional and morphological features of brain vasculature that limit their applicability for these purposes. These features include the physiologically relevant mechanical properties and the dynamic cellular environment of blood vessels subjected to constant fluid flow. Herein, we developed three-dimensionally (3D) printed aneurysm-bearing vascularized tissue structures using gelatin-fibrin hydrogel of which the inner vessel walls were seeded with human cerebral microvascular endothelial cells (hCMECs). The hCMECs readily exhibited cellular attachment, spreading, and confluency all around the vessel walls, including the aneurysm walls. Additionally, thein vitroplatform was directly amenable to flow measurements via particle image velocimetry, enabling the direct assessment of the vascular flow dynamics for comparison to a 3D computational fluid dynamics model. Detachable coils were delivered into the printed aneurysm sac through the vessel using a microcatheter and static blood plasma clotting was monitored inside the aneurysm sac and around the coils. This biomimeticin vitroaneurysm model is a promising method for examining the biocompatibility and hemostatic efficiency of embolization devices and for providing hemodynamic information which would aid in predicting aneurysm rupture or healing response after treatment.


Subject(s)
Bioprinting , Embolization, Therapeutic , Intracranial Aneurysm , Blood Vessel Prosthesis , Endothelial Cells , Humans , Intracranial Aneurysm/therapy
14.
BMC Endocr Disord ; 20(1): 130, 2020 Aug 26.
Article in English | MEDLINE | ID: mdl-32843004

ABSTRACT

BACKGROUND: Although important achievements have been done in type 2 diabetes mellitus (T2D) treatment and glycemic control, new strategies may take advantage of non-pharmacological approaches and of other potential determinants of health (e.g., socioeconomic status, education, diabetes knowledge, physical activity, and self-care behavior). However, the relationships between these factors are not totally clear and have not been studied in the context of large urban settings. This study aimed to explore the relationship between these determinants of glycemic control (GC) in a low-income urban population from Mexico City, focused in exploring potential the mediation of self-care behaviors in the association between diabetes knowledge and GC. METHODS: A multicenter cross-sectional study was conducted in patients with type 2 diabetes (T2D) from 28 primary care outpatient centers located in Mexico City. Using multivariable-adjusted models, we determined the associations between diabetes knowledge, self-care behaviors, and GC. The mediation analyses to determine the pathways on glycemic control were done using linear regression models, where the significance of indirect effects was calculated with bootstrapping. RESULTS: The population (N = 513) had a mean age of 53.8 years (standard deviation: 11.3 yrs.), and 65.9% were women. Both socioeconomic status and level of education were directly associated with diabetes knowledge. Using multivariable-adjusted linear models, we found that diabetes knowledge was associated with GC (ß: -0.102, 95% Confidence Interval [95% CI] -0.189, - 0.014). Diabetes knowledge was also independently associated with self-care behavior (for physical activity: ß: 0.181, 95% CI 0.088, 0.273), and self-care behavior was associated with GC (for physical activity: ß: -0.112, 95% CI -0.194, - 0.029). The association between diabetes knowledge and GC was not observed after adjustment for self-care behaviors, especially physical activity (ß: -0.084, 95% CI -0.182, 0.014, p-value: 0.062). Finally, the mediation models showed that the effect of diabetes knowledge on GC was 17% independently mediated by physical activity (p-value: 0.049). CONCLUSIONS: Socioeconomic and educational gradients influence diabetes knowledge among primary care patients with type 2 diabetes. Self-care activities, particularly physical activity, mediated the effect of diabetes knowledge on GC. Our results indicate that diabetes knowledge should be reinforced in low-income T2D patients, with an emphasis on the benefits physical activity has on improving GC.


Subject(s)
Diabetes Mellitus, Type 2 , Glycemic Control , Health Behavior/physiology , Health Knowledge, Attitudes, Practice , Social Determinants of Health , Adult , Aged , Cross-Sectional Studies , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/therapy , Educational Status , Exercise , Female , Glycemic Control/methods , Glycemic Control/standards , Glycemic Control/statistics & numerical data , Humans , Male , Mexico/epidemiology , Middle Aged , Poverty , Primary Health Care/statistics & numerical data , Self Care/methods , Self Care/standards , Self Care/statistics & numerical data , Social Class , Social Determinants of Health/statistics & numerical data , Social Support
15.
Int J Equity Health ; 19(1): 75, 2020 05 24.
Article in English | MEDLINE | ID: mdl-32448267

ABSTRACT

BACKGROUND: Although important advances in treatment strategies have been developed in type 2 diabetes mellitus (T2DM), large gaps exist in achieving glycemic control and preventing complications, particularly in low-and middle-income countries, which suggests a potential effect of social determinants of health (SDH, i.e., education level and socioeconomic status). However, few studies have determined the role of SDH and other determinants of health (ODH, i.e., diabetes knowledge and self-care scores) in achieving T2DM goals during effective multidisciplinary interventions. We aimed to examine a multicomponent integrated care (MIC) program on diabetes care goals and determine the effect of SDH and ODH on T2DM patients. METHODS: A before-and-after design (a pretest, a 5-month intervention, and a follow-up) was used in a T2DM population from Mexico City. The SDH included education level and socioeconomic status; the ODH included diabetes knowledge, self-care scores, and deltas (i.e., differences between baseline and follow-up scores). The triple-target goal (glycated hemoglobin, blood pressure, and LDL-cholesterol) was established as a measurement of T2DM goals. RESULTS: The DIABEMPIC (DIABetes EMPowerment and Improvement of Care) intervention (n = 498) reduced the glycated hemoglobin levels (mean reduction 2.65%, standard deviation [SD]: 2.02%) and cardiometabolic parameters; it also improved health-related quality of life. From 1.81% at baseline, 25.9% of participants (p-value< 0.001) achieved the triple-target goal. We found a significant association between education level (p-value = 0.010), diabetes knowledge at baseline (p-value = 0.004), and self-care scores at baseline (p-value = 0.033) in the delta (change between baseline and follow-up assessments) of HbA1c levels. Improvements (increase) in diabetes knowledge (p-value = 0.006) and self-care scores (p-value = 0.002) were also associated with greater reductions in HbA1c. CONCLUSIONS: MIC strategies in urban primary care settings contribute to control of T2DM. SDH, such as education level, and ODH (diabetes knowledge and self-care scores at baseline) play a key role in improving glycemic control in these settings.


Subject(s)
Diabetes Mellitus, Type 2/therapy , Goals , Health Knowledge, Attitudes, Practice , Primary Health Care/methods , Self Care , Social Determinants of Health , Aged , Blood Glucose/physiology , Blood Pressure , Cholesterol, LDL/physiology , Female , Glycated Hemoglobin/physiology , Humans , Male , Mexico/epidemiology , Middle Aged , Social Class
16.
Biomaterials ; 250: 120035, 2020 08.
Article in English | MEDLINE | ID: mdl-32334200

ABSTRACT

The biophysical properties of extracellular matrices (ECM) are known to regulate cell behavior, however decoupling cell behavior changes due to the relative contributions of material microstructure versus biomechanics or nutrient permeability remains challenging, especially within complex, multi-material matrices. We developed four gelatin-fibrin interpenetrating network (IPN) formulations which are identical in composition but possess variable gelatin molecular weight distributions, and display differences in microstructure, biomechanics, and diffusivity. In this work we interrogate the response of multicellular tumor spheroids to these IPN formulations and found that a high stiffness, gelatin-network dominated IPNs impeded remodeling and invasion of multicellular tumor spheroids; whereas relatively lower stiffness, fibrin-network dominated IPNs permitted protease-dependent remodeling and spheroid invasion. Cell proliferation correlated to nutrient diffusivity across tested IPN formulations. These findings demonstrate the complexity of ECM IPNs, relative to single polymer matrices, and highlight that cell response does not derive from a single aspect of the ECM, but rather from the interplay of multiple biomechanical properties. The methodology developed here represents a framework for future studies which aim to characterize cellular phenotypic responses to biophysical cues present within complex, multi-material matrices.


Subject(s)
Gelatin , Neoplasms , Fibrin , Humans , Hydrogels , Polymers
17.
PLoS One ; 15(2): e0228776, 2020.
Article in English | MEDLINE | ID: mdl-32032368

ABSTRACT

The Mediterranean Basin is a biodiversity hotspot, where islands play a key role because of their high biological diversity, degree of endemicity and human pressure. One of these islands, Sardinia, is a good evolutionary laboratory, especially for the study of complex genera, such as Centaurea. In particular, endemic species of Centaurea sect. Centaurea from Sardinia provides an interesting case study of plant evolution on continental islands. We attempted to clarify the processes leading to the diversification of Centaurea species on Sardinia using bi-parentally inherited nuclear markers and maternally inherited plastid markers. Our plastid results revealed the presence of five lineages of sect. Centaurea on the island. Three of them were defined as three species: C. ferulacea, C. filiformis and C. horrida. The other two lineages highlighted the complex evolutionary history of the two polyploids C. corensis and C. magistrorum. Multiple colonization events from the mainland involving the C. deusta and C. paniculata lineages among others, have led to the diversity of sect. Centaurea on Sardinia. One colonization event likely followed a southern path via the land connection between the mainland, the Calabrian Plate and Sardinia. A second pathway likely followed a northern connection, probably through the Tuscan Archipelago. Implications of these findings on conservation efforts for Centaurea endemics on Sardinia are also discussed.


Subject(s)
Biological Evolution , Centaurea/growth & development , Centaurea/classification , Centaurea/genetics , DNA, Plant/chemistry , DNA, Plant/isolation & purification , DNA, Plant/metabolism , Genetic Linkage , Islands , Italy , Phylogeny , Plastids/genetics , Polyploidy
18.
Ann Biomed Eng ; 48(2): 780-793, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31741228

ABSTRACT

Much of what is currently known about the role of the blood-brain barrier (BBB) in regulating the passage of chemicals from the blood stream to the central nervous system (CNS) comes from animal in vivo models (requiring extrapolation to human relevance) and 2D static in vitro systems, which fail to capture the rich cell-cell and cell-matrix interactions of the dynamic 3D in vivo tissue microenvironment. In this work we have developed a BBB platform that allows for a high degree of customization in cellular composition, cellular orientation, and physiologically-relevant fluid dynamics. The system characterized and presented in this study reproduces key characteristics of a BBB model (e.g. tight junctions, efflux pumps) allowing for the formation of a selective and functional barrier. We demonstrate that our in vitro BBB is responsive to both biochemical and mechanical cues. This model further allows for culture of a CNS-like space around the BBB. The design of this platform is a valuable tool for studying BBB function as well as for screening of novel therapeutics.


Subject(s)
Blood-Brain Barrier/metabolism , Models, Cardiovascular , Blood-Brain Barrier/cytology , Cell Communication , Cell Line, Transformed , Extracellular Matrix , Humans
19.
J Neurosci Methods ; 329: 108460, 2020 01 01.
Article in English | MEDLINE | ID: mdl-31626846

ABSTRACT

BACKGROUND: The emergence of three-dimensional (3D) cell culture in neural tissue engineering has significantly elevated the complexity and relevance of in vitro systems. This is due in large part to the incorporation of biomaterials to impart structural dimensionality on the neuronal cultures. However, a comprehensive understanding of how key seeding parameters affect changes in cell distribution and viability remain unreported. NEW METHOD: In this study, we systematically evaluated permutations in seeding conditions (i.e., cell concentration and atmospheric CO2 levels) to understand how these affect key parameters in 3D culture characterization (i.e., cell health and distribution). Primary rat cortical neurons (i.e., 2 × 106, 4 × 106, and 1 × 107 cells/mL) were entrapped in collagen blended with ECM proteins (ECM-Collagen) and exposed to atmospheric CO2 (i.e., 0 vs 5% CO2) during fibrillogenesis. RESULTS: At 14 days in vitro (DIV), cell distribution within the hydrogel was dependent on cell concentration and atmospheric CO2 during fibrillogenesis. A uniform distribution of cells was observed in cultures with 2 × 106 and 4 × 106 cells/mL in the presence of 5% CO2, while a heterogeneous distribution was observed in cultures with 1 × 107 cells/mL or in the absence of CO2. Furthermore, increased cell concentration was proportional to the rise in cell death at 14 DIV, although cells remain viable >30 DIV. COMPARISON WITH EXISTING METHODS: ECM-Collagen gels have been shown to increase cell viability of neurons long-term. CONCLUSION: In using ECM-collagen gels, we highlight the importance of optimizing seeding parameters and thorough 3D culture characterization to understand the neurophysiological responses of these 3D systems.


Subject(s)
Cell Encapsulation/standards , Cerebral Cortex , Collagen Type I , Extracellular Matrix , Hydrogels , Neurons , Primary Cell Culture/standards , Cell Encapsulation/methods , Cerebral Cortex/cytology , Humans , Neurons/cytology , Primary Cell Culture/methods
20.
Mol Phylogenet Evol ; 137: 313-332, 2019 08.
Article in English | MEDLINE | ID: mdl-31059792

ABSTRACT

Classification of tribe Cardueae in natural subtribes has always been a challenge due to the lack of support of some critical branches in previous phylogenies based on traditional Sanger markers. With the aim to propose a new subtribal delimitation, we applied a Hyb-Seq approach to a set of 76 Cardueae species representing all subtribes and informal groups defined in the tribe, targeting 1061 nuclear conserved orthology loci (COS) designed for Compositae and obtaining chloroplast coding regions as by-product of off-target reads. For the extraction of the target nuclear data, we used two strategies, PHYLUCE and HybPiper, and 776 and 1055 COS loci were recovered with each of them, respectively. Additionally, 87 chloroplast genes were assembled and annotated. With three datasets, phylogenetic relationships were reconstructed using both concatenation and coalescent approaches. Phylogenetic analyses of the nuclear datasets fully resolved virtually all nodes with very high support. Nuclear and plastid tree topologies are mostly congruent with a very limited number of incongruent nodes. Based on the well-solved phylogenies obtained, we propose a new taxonomic scheme of 12 monophyletic and morphologically consistent subtribes: Carlininae, Cardopatiinae, Echinopsinae, Dipterocominae (new), Xerantheminae (new), Berardiinae (new), Staehelininae (new), Onopordinae (new), Carduinae (redelimited), Arctiinae (new), Saussureinae (new), and Centaureinae. In addition, we further updated the temporal framework for origin and diversification of these subtribes. Our results highlight the power of Hyb-Seq over Sanger sequencing of a few DNA markers in solving phylogenetic relationships of traditionally difficult groups.


Subject(s)
Asteraceae/classification , Asteraceae/genetics , Cell Nucleus/genetics , DNA, Plant/genetics , Genetic Variation , Phylogeny , Plastids/genetics , Sequence Analysis, DNA , Calibration , Databases, Genetic , Geography , Time Factors
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