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1.
Nat Mater ; 23(2): 281-289, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38177377

RESUMEN

Some animals form transient, responsive and solid-like ensembles through dynamic structural interactions. These ensembles demonstrate emergent responses such as spontaneous self-assembly, which are difficult to achieve in synthetic soft matter. Here we use shape-morphing units comprising responsive polymers to create solids that self-assemble, modulate their volume and disassemble on demand. The ensemble is composed of a responsive hydrogel, liquid crystal elastomer or semicrystalline polymer ribbons that reversibly bend or twist. The dispersions of these ribbons mechanically interlock, inducing reversible aggregation. The aggregated liquid crystal elastomer ribbons have a 12-fold increase in the yield stress compared with cooled dispersion and contract by 34% on heating. Ribbon type, concentration and shape dictate the aggregation and govern the global mechanical properties of the solid that forms. Coating liquid crystal elastomer ribbons with a liquid metal begets photoresponsive and electrically conductive aggregates, whereas seeding cells on hydrogel ribbons enables self-assembling three-dimensional scaffolds, providing a versatile platform for the design of dynamic materials.

2.
J Neurooncol ; 169(3): 555-561, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38963658

RESUMEN

PURPOSE: Central nervous system (CNS) metastases from lung cancers and melanoma, significantly contribute to morbidity and mortality. Despite advances in local therapies, there is a need for effective systemic treatments. Pembrolizumab, a PD-1 inhibitor, has shown promise for some patients with untreated brain metastases from melanoma and non-small cell lung cancer (NSCLC). This study aims to analyze the response of brain metastasis to pembrolizumab and associate characteristics like size and location with treatment outcome. METHODS: This retrospective study used imaging data from a phase II trial of pembrolizumab in melanoma or NSCLC patients with untreated brain metastases. MRI evaluations were conducted at 2 month intervals, with each brain metastasis treated as a distinct tumor for response assessment, based on modified RECIST criteria (maximum 5 lesions, 5 mm target lesions). RESULTS: Of 130 individual target metastases (> 5 mm), in 65 patients with NSCLC (90 metastases) and Melanoma (40 metastases), 32 (24.6%) demonstrated complete resolution, 24 (18.5%) had partial resolution, 32 (24.6%) were SD and 42 (32.3%) demonstrated PD. Those smaller than 10 mm were more likely to show complete resolution (p = 0.0218), while those ≥ 10 mm were more likely to have PR. There was no significant association between size, number or location (supratentorial vs. infratentorial) and lesion progression. The median time to metastatic lesion progression in the brain was 5.7-7 weeks. CONCLUSION: Pembrolizumab is effective in brain metastases from NSCLC and melanoma, showing response (CR + PR) in 43% and progression (PD) in 32% of metastases. With the median time to CNS progression of 5.7-7 weeks, careful radiographic monitoring is essential to guide timely local treatment decisions.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Antineoplásicos Inmunológicos , Neoplasias Encefálicas , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Melanoma , Humanos , Anticuerpos Monoclonales Humanizados/uso terapéutico , Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/diagnóstico por imagen , Masculino , Estudios Retrospectivos , Femenino , Melanoma/tratamiento farmacológico , Melanoma/patología , Persona de Mediana Edad , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Anciano , Antineoplásicos Inmunológicos/uso terapéutico , Adulto , Inmunoterapia/métodos , Resultado del Tratamiento , Estudios de Seguimiento , Anciano de 80 o más Años
3.
Proc Natl Acad Sci U S A ; 117(24): 13329-13338, 2020 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-32461372

RESUMEN

Two-dimensional (2D) molybdenum disulfide (MoS2) nanomaterials are an emerging class of biomaterials that are photoresponsive at near-infrared wavelengths (NIR). Here, we demonstrate the ability of 2D MoS2 to modulate cellular functions of human stem cells through photothermal mechanisms. The interaction of MoS2 and NIR stimulation of MoS2 with human stem cells is investigated using whole-transcriptome sequencing (RNA-seq). Global gene expression profile of stem cells reveals significant influence of MoS2 and NIR stimulation of MoS2 on integrins, cellular migration, and wound healing. The combination of MoS2 and NIR light may provide new approaches to regulate and direct these cellular functions for the purposes of regenerative medicine as well as cancer therapy.


Asunto(s)
Disulfuros/efectos de la radiación , Células Madre Mesenquimatosas/efectos de la radiación , Molibdeno/efectos de la radiación , Nanoestructuras/efectos de la radiación , Adhesión Celular/efectos de la radiación , Movimiento Celular/efectos de la radiación , Supervivencia Celular , Disulfuros/química , Disulfuros/metabolismo , Perfilación de la Expresión Génica , Humanos , Rayos Infrarrojos , Integrinas/genética , Integrinas/metabolismo , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Molibdeno/química , Molibdeno/metabolismo , Nanoestructuras/química , Fármacos Fotosensibilizantes , Transducción de Señal/efectos de la radiación
4.
Semin Cancer Biol ; 70: 134-138, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-32569823

RESUMEN

Kidney stone is a common urological condition, the prevalence and incidence of which has escalated in the last few years due to dietary habits and other related medical conditions such as obesity and diabetes mellitus. It is a chronic disease which leads to loss of kidney function(s) and nephrectomy. Chronic kidney stone disease has been shown to be associated with transitional cell carcinoma (TCC) or renal cell carcinoma (RCC) and kidney tumors have been found to be more frequent among patients with kidney stones. Although hyperoxaluria is mainly responsible for kidney stone formation, dysbiosis of the gut and urinary tract microbiome may in part contribute to kidney stone disease. Dysbiosis of the gut and urinary tract microbiome have been linked to kidney stone diseases with both gain and loss of function. The review provides a detailed study of how the variations in the microbiome of the human gut and urinary tract result in the chronic kidney stone diseases which are associated with increased papillary RCC risks.


Asunto(s)
Carcinoma de Células Renales/patología , Disbiosis/fisiopatología , Cálculos Renales/complicaciones , Neoplasias Renales/patología , Microbiota , Animales , Carcinoma de Células Renales/etiología , Humanos , Neoplasias Renales/etiología , Factores de Riesgo
5.
Graefes Arch Clin Exp Ophthalmol ; 259(8): 2069-2083, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33625566

RESUMEN

Ocular complications associated with anesthesia in ocular and non-ocular surgeries are rare adverse events which may present with clinical presentations vacillating between easily treatable corneal abrasions to more serious complication such as irreversible bilateral vision loss. In this review, we outline the different techniques of anesthetic delivery in ocular surgeries and highlight the incidence and etiologies of associated injuries. The changes in vision in non-ocular surgeries are mistaken for residual sedation or anesthetics, therefore require high clinical suspicion on part of the treating ophthalmologists, to ensure early diagnosis, adequate and swift management especially in surgeries such as cardiac, spine, head and neck, and some orthopedic procedures, that have a comparatively higher incidence of ocular complications. In this article, we review the literature for reports on the clinical incidence of different ocular complications associated with anesthesia in non-ocular surgeries and outline the current understanding of pathophysiological processes associated with these adverse events.


Asunto(s)
Anestesia , Lesiones de la Cornea , Anestesia/efectos adversos , Ojo , Humanos , Procedimientos Quirúrgicos Oftalmológicos/efectos adversos , Trastornos de la Visión
6.
J Law Med ; 28(2): 567-585, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33768759

RESUMEN

As a means of abating the crises of society, the idea of equality has long been a progressive, universal, moral and legal principle to seek justice. However, equality is open to a broad spectrum of meanings and practical applications, mainly due to its endorsement of different interpretations and concepts that give rise to complementary and competing interests. Likewise, the "capability approach", which is proposed as an alternative to the "ideal of equality", is not only contentious but also insufficient to build the theoretical basis of an ethical health care paradigm. This article aims to expand the discussion on the ambiguity around the concept of equality, particularly how it interacts with the diversities in human capabilities in a given context.


Asunto(s)
Principios Morales , Justicia Social , Atención a la Salud , Humanos
7.
J Basic Microbiol ; 60(3): 253-267, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31750957

RESUMEN

A new bacterial strain producing extracellular cholesterol oxidase (ChOx) was isolated and identified as Castellaniella sp. COX. The ChOx was purified by salting-out and ion-exchange chromatography up to 10.4-fold, with a specific activity of 15 U/mg with a molecular mass of 59 kDa. The purified ChOx exhibited pH 8.0 and temperature 40°C for its optimum activity. The enzyme showed stability over a wide pH range and was most stable at pH value 7.0, and at pH 8.0, it retained almost 86% of its initial activity after 3 h of incubation at 37°C. The enzyme possessed a half-life of 8 h at 37°C, 7 h at 40°C, and 3 h at 50°C. A Lineweaver-Burk plot was calibrated to determine its Km (0.16 mM) and Vmax (18.7 µmol·mg-1 ·min-1 ). The ChOx activity was enhanced with Ca2+ , Mg2+ , and Mn2+ while it was inhibited by Hg2+ , Ba2+ , Fe2+ , Cu2+ , and Zn2+ ions. Organic solvents like acetone, n-butanol, toluene, dimethyl sulfoxide, chloroform, benzene, and methanol were well tolerated by the enzyme while iso-propanol and ethanol were found to enhance the activity of purified ChOx. ChOx induced cytotoxicity with an IC50 value of 1.78 and 1.88 U/ml against human RD and U87MG established cell lines, respectively, while broadly sparing the normal human cells.


Asunto(s)
Alcaligenaceae/enzimología , Proteínas Bacterianas/química , Proteínas Bacterianas/farmacología , Colesterol Oxidasa/química , Colesterol Oxidasa/farmacología , Alcaligenaceae/clasificación , Alcaligenaceae/genética , Alcaligenaceae/aislamiento & purificación , Proteínas Bacterianas/aislamiento & purificación , Cationes/química , Línea Celular , Supervivencia Celular/efectos de los fármacos , Colesterol Oxidasa/aislamiento & purificación , Detergentes/química , Estabilidad de Enzimas , Humanos , Concentración de Iones de Hidrógeno , Concentración 50 Inhibidora , Cinética , Peso Molecular , Oxidación-Reducción , Solventes/química , Temperatura
8.
Physiol Mol Biol Plants ; 26(1): 95-106, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32158123

RESUMEN

Rose (Rosa × hybrid L.) is one of the most important commercial ornamental crops cultivated worldwide for its beauty, fragrance and nutraceutical values. Characterization of rose germplasm provides precise information about the extent of diversity present among the cultivars. It also helps in cultivar identification, intellectual property right protection, variety improvement and genetic diversity conservation. In the present study, 109 Indian bred rose cultivars were characterized using 59 morphological and 48 SSR markers. Out of 48 SSRs used, 31 markers exhibited polymorphism and 96 alleles were identified with an average of 3.9 alleles per locus. Nei's expected heterozygosity value of each locus ranged from 0.08 (with SSR ABRII/RPU32) to 0.78 (SSR Rh58). The similarity coefficient values ranged from 0.42 to 0.90 which indicated presence of moderated diversity among Indian cultivars. The neighbor-joining tree based on morphological data grouped the cultivars into two major clusters and several minor clusters based on their morphological resemblance. However, UPGMA dendrogram constructed using matching coefficient values grouped the cultivars into eight different clusters. Interpopulation analysis revealed higher genetic similarities between Hybrid Tea and Floribunda cultivars. An analysis for presence of population sub-structure grouped the Indian cultivars into eight different genetic groups. Analysis of molecular variance revealed apportioning of 97.59% of the variation to within subgroup diversity and 3.07% to between the cultivar groups. We have demonstrated here successful utilization of robust SSR to distinguish cultivars and assess genetic diversity among Indian bred rose cultivars. The information provided here is useful for cultivar identification and protection, cultivar improvement and genetic diversity conservation.

9.
PLoS Genet ; 12(2): e1005854, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26870957

RESUMEN

DNA methylation acts in concert with restriction enzymes to protect the integrity of prokaryotic genomes. Studies in a limited number of organisms suggest that methylation also contributes to prokaryotic genome regulation, but the prevalence and properties of such non-restriction-associated methylation systems remain poorly understood. Here, we used single molecule, real-time sequencing to map DNA modifications including m6A, m4C, and m5C across the genomes of 230 diverse bacterial and archaeal species. We observed DNA methylation in nearly all (93%) organisms examined, and identified a total of 834 distinct reproducibly methylated motifs. This data enabled annotation of the DNA binding specificities of 620 DNA Methyltransferases (MTases), doubling known specificities for previously hard to study Type I, IIG and III MTases, and revealing their extraordinary diversity. Strikingly, 48% of organisms harbor active Type II MTases with no apparent cognate restriction enzyme. These active 'orphan' MTases are present in diverse bacterial and archaeal phyla and show motif specificities and methylation patterns consistent with functions in gene regulation and DNA replication. Our results reveal the pervasive presence of DNA methylation throughout the prokaryotic kingdoms, as well as the diversity of sequence specificities and potential functions of DNA methylation systems.


Asunto(s)
Epigenómica , Células Procariotas/metabolismo , Secuencia Conservada , Metilación de ADN/genética , Replicación del ADN/genética , Enzimas de Restricción-Modificación del ADN/clasificación , Enzimas de Restricción-Modificación del ADN/metabolismo , Evolución Molecular , Regulación de la Expresión Génica , Genoma , Metiltransferasas/metabolismo , Anotación de Secuencia Molecular , Familia de Multigenes , Motivos de Nucleótidos/genética , Filogenia , Especificidad por Sustrato
10.
Prep Biochem Biotechnol ; 49(9): 916-926, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31322478

RESUMEN

A Gram-positive, rod-shaped, endospore-forming, and RNA-degrading bacterium RB-5 was isolated from a soil sample. Based on 16-rDNA gene sequence, the bacterium RB-5 was identified as Bacillus safensis (Accession number KX443714.1). The bacterium appeared to be related to Bacillus safensis KL-052, an other-member of genus Bacillus. One-factor-at-a-time (OFAT) and Response Surface Methodology (RSM) statistical approaches were used to optimize the fermentation broth to obtain an improved extracellular RNase production from B. safensis RB-5. These approaches improved RNase activity of B. safensis KL-052 from 4.26 to 7.85 U/mL. The OFAT approach was used to study the effects of supplementation of carbon, nitrogen and physical conditions, which included temperature, pH and agitation rate on extracellular RNase production by B. safensis KL-052. Five variables screened by Central Composite Design (CCD) were employed to evaluate their interactive effects on RNase production by the organism. CCD selected 25 factorial values obtained by the statistical approach were peptone 1.13% (w/v), sodium nitrate 1.13% (w/v), MgSO4 0.06% (w/v), pH 8.5, and temperature 35 °C for RNase production by B. safensis. The highest predicted value of RNase was 7.05 U/ml while actual obtained value was 7.85 U/ml that was ∼84% and 1.84-fold higher than OFAT approach.


Asunto(s)
Bacillus/enzimología , Ribonucleasas/metabolismo , Bacillus/genética , Bacillus/aislamiento & purificación , Bacillus/metabolismo , Carbono/metabolismo , Fermentación , Concentración de Iones de Hidrógeno , Microbiología Industrial , Nitrógeno/metabolismo , Peptonas/metabolismo , Filogenia , Ribonucleasas/genética , Microbiología del Suelo , Temperatura
11.
BMC Genomics ; 16: 856, 2015 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-26496746

RESUMEN

BACKGROUND: The rapid development of sequencing technologies has provided access to environments that were either once thought inhospitable to life altogether or that contain too few cells to be analyzed using genomics approaches. While 16S rRNA gene microbial community sequencing has revolutionized our understanding of community composition and diversity over time and space, it only provides a crude estimate of microbial functional and metabolic potential. Alternatively, shotgun metagenomics allows comprehensive sampling of all genetic material in an environment, without any underlying primer biases. Until recently, one of the major bottlenecks of shotgun metagenomics has been the requirement for large initial DNA template quantities during library preparation. RESULTS: Here, we investigate the effects of varying template concentrations across three low biomass library preparation protocols on their ability to accurately reconstruct a mock microbial community of known composition. We analyze the effects of input DNA quantity and library preparation method on library insert size, GC content, community composition, assembly quality and metagenomic binning. We found that library preparation method and the amount of starting material had significant impacts on the mock community metagenomes. In particular, GC content shifted towards more GC rich sequences at the lower input quantities regardless of library prep method, the number of low quality reads that could not be mapped to the reference genomes increased with decreasing input quantities, and the different library preparation methods had an impact on overall metagenomic community composition. CONCLUSIONS: This benchmark study provides recommendations for library creation of representative and minimally biased metagenome shotgun sequencing, enabling insights into functional attributes of low biomass ecosystem microbial communities.


Asunto(s)
Metagenoma , Metagenómica , Microbiota , Archaea/genética , Bacterias/genética , Composición de Base , Biomasa , Mapeo Contig , Biblioteca de Genes , Metagenómica/métodos , Análisis de Secuencia de ADN
12.
J Air Waste Manag Assoc ; 64(11): 1328-40, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25509554

RESUMEN

A computational fluid dynamics (CFD) methodology for simulating the combustion process has been validated with experimental results. Three different types of experimental setups were used to validate the CFD model. These setups include an industrial-scale flare setups and two lab-scale flames. The CFD study also involved three different fuels: C3H6/CH/Air/N2, C2H4/O2/Ar and CH4/Air. In the first setup, flare efficiency data from the Texas Commission on Environmental Quality (TCEQ) 2010 field tests were used to validate the CFD model. In the second setup, a McKenna burner with flat flames was simulated. Temperature and mass fractions of important species were compared with the experimental data. Finally, results of an experimental study done at Sandia National Laboratories to generate a lifted jet flame were used for the purpose of validation. The reduced 50 species mechanism, LU 1.1, the realizable k-epsilon turbulence model, and the EDC turbulence-chemistry interaction model were usedfor this work. Flare efficiency, axial profiles of temperature, and mass fractions of various intermediate species obtained in the simulation were compared with experimental data and a good agreement between the profiles was clearly observed. In particular the simulation match with the TCEQ 2010 flare tests has been significantly improved (within 5% of the data) compared to the results reported by Singh et al. in 2012. Validation of the speciated flat flame data supports the view that flares can be a primary source offormaldehyde emission.


Asunto(s)
Simulación por Computador , Incendios , Modelos Teóricos , Aire , Gases , Hidrodinámica , Industrias , Temperatura
13.
Nat Commun ; 15(1): 8136, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39289340

RESUMEN

Diminished mitochondrial function underlies many rare inborn errors of energy metabolism and contributes to more common age-associated metabolic and neurodegenerative disorders. Thus, boosting mitochondrial biogenesis has been proposed as a potential therapeutic approach for these diseases; however, currently we have a limited arsenal of compounds that can stimulate mitochondrial function. In this study, we designed molybdenum disulfide (MoS2) nanoflowers with predefined atomic vacancies that are fabricated by self-assembly of individual two-dimensional MoS2 nanosheets. Treatment of mammalian cells with MoS2 nanoflowers increased mitochondrial biogenesis by induction of PGC-1α and TFAM, which resulted in increased mitochondrial DNA copy number, enhanced expression of nuclear and mitochondrial-DNA encoded genes, and increased levels of mitochondrial respiratory chain proteins. Consistent with increased mitochondrial biogenesis, treatment with MoS2 nanoflowers enhanced mitochondrial respiratory capacity and adenosine triphosphate production in multiple mammalian cell types. Taken together, this study reveals that predefined atomic vacancies in MoS2 nanoflowers stimulate mitochondrial function by upregulating the expression of genes required for mitochondrial biogenesis.


Asunto(s)
Disulfuros , Mitocondrias , Molibdeno , Nanopartículas , Molibdeno/farmacología , Molibdeno/química , Molibdeno/metabolismo , Disulfuros/química , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Humanos , Nanopartículas/química , Biogénesis de Organelos , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , Animales , Adenosina Trifosfato/metabolismo , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Ratones
14.
Nat Methods ; 7(10): 807-12, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20852648

RESUMEN

The predominance of rRNAs in the transcriptome is a major technical challenge in sequence-based analysis of cDNAs from microbial isolates and communities. Several approaches have been applied to deplete rRNAs from (meta)transcriptomes, but no systematic investigation of potential biases introduced by any of these approaches has been reported. Here we validated the effectiveness and fidelity of the two most commonly used approaches, subtractive hybridization and exonuclease digestion, as well as combinations of these treatments, on two synthetic five-microorganism metatranscriptomes using massively parallel sequencing. We found that the effectiveness of rRNA removal was a function of community composition and RNA integrity for these treatments. Subtractive hybridization alone introduced the least bias in relative transcript abundance, whereas exonuclease and in particular combined treatments greatly compromised mRNA abundance fidelity. Illumina sequencing itself also can compromise quantitative data analysis by introducing a G+C bias between runs.


Asunto(s)
Bacterias/clasificación , Euryarchaeota/clasificación , Perfilación de la Expresión Génica/métodos , ARN de Archaea/genética , ARN Bacteriano/genética , ARN Mensajero/genética , ARN Ribosómico/genética , Bacterias/genética , ADN de Archaea/genética , ADN Bacteriano/genética , Euryarchaeota/genética , Exonucleasas/metabolismo , Hibridación in Situ , ARN Ribosómico 16S/genética , ARN Ribosómico 23S/genética , Reproducibilidad de los Resultados , Alineación de Secuencia , Análisis de Secuencia de ARN
15.
PeerJ ; 11: e15820, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37701831

RESUMEN

Background: Genetic analysis of gladiolus germplasm using simple sequence repeat (SSR) markers is largely missing due to scarce genomic information. Hence, microsatellites identified for related genera or species may be utilized to understand the genetic diversity and assess genetic relationships among cultivated gladiolus varieties. Methods: In the present investigation, we screened 26 genomic SSRs (Gladiolus palustris, Crocus sativus, Herbertia zebrina, Sysirinchium micranthum), 14 chloroplast SSRs (Gladiolus spp., chloroplast DNA regions) and 25 Iris Expressed Sequence Tags (ESTs) derived SSRs across the 84 gladiolus (Gladiolus × grandiflorus L.) genotypes. Polymorphic markers detected from amplified SSRs were used to calculate genetic diversity estimates, analyze population structure, cluster analysis and principal coordinate analysis (PCoA). Results: A total of 41 SSRs showed reproducible amplification pattern among the selected gladiolus cultivars. Among these, 17 highly polymorphic SSRs revealed a total of 58 polymorphic alleles ranging from two to six with an average of 3.41 alleles per marker. Polymorphic information content (PIC) values ranged from 0.11 to 0.71 with an average value of 0.48. A total of 4 SSRs were selectively neutral based on the Ewens-Watterson test. Hence, 66.66% of Gladiolus palustris, 48% of Iris spp. EST, 71.42% of Crocus sativus SSRs showed cross-transferability among the gladiolus genotypes. Analysis of genetic structure of 84 gladiolus genotypes revealed two subpopulations; 35 genotypes were assigned to subpopulation 1, 37 to subpopulation 2 and the remaining 12 genotypes could not be attributed to either subpopulation. Analysis of molecular variance indicated maximum variance (53.59%) among individuals within subpopulations, whereas 36.55% of variation among individuals within the total population. The least variation (9.86%) was noticed between two subpopulations. Moderate (FST = 0.10) genetic differentiation between two subpopulations was observed. The grouping pattern of population structure was consistent with the unweighted pair group method with arithmetic mean (UPGMA) dendrogram based on simple matching dissimilarity coefficient and PCoA. Conclusion: SSR markers from the present study can be utilized for cultivar identification, conservation and sustainable utilization of gladiolus genotypes for crop improvement. Genetic relationships assessed among the genotypes of respective clusters may assist the breeders in selecting desirable parents for crossing.


Asunto(s)
Crocus , Iridaceae , Género Iris , Humanos , Genotipo , Iridaceae/genética , Variación Genética/genética
16.
J Biomed Mater Res A ; 111(10): 1577-1587, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37199446

RESUMEN

Granular hydrogels are a promising biomaterial for a wide range of biomedical applications, including tissue regeneration, drug/cell delivery, and 3D printing. These granular hydrogels are created by assembling microgels through the jamming process. However, current methods for interconnecting the microgels often limit their use due to the reliance on postprocessing for crosslinking through photoinitiated reactions or enzymatic catalysis. To address this limitation, we incorporated a thiol-functionalized thermo-responsive polymer into oxidized hyaluronic acid microgel assemblies. The rapid exchange rate of thiol-aldehyde dynamic covalent bonds allows the microgel assembly to be shear-thinning and self-healing, with the phase transition behavior of the thermo-responsive polymer serving as secondary crosslinking to stabilize the granular hydrogels network at body temperature. This two-stage crosslinking system provides excellent injectability and shape stability, while maintaining mechanical integrity. In addition, the aldehyde groups of the microgels act as covalent binding sites for sustained drug release. These granular hydrogels can be used as scaffolds for cell delivery and encapsulation, and can be 3D printed without the need for post-printing processing to maintain mechanical stability. Overall, our work introduces thermo-responsive granular hydrogels with promising potential for various biomedical applications.


Asunto(s)
Hidrogeles , Microgeles , Hidrogeles/química , Ingeniería de Tejidos/métodos , Materiales Biocompatibles/química , Polímeros , Impresión Tridimensional
17.
Ophthalmol Sci ; : 100354, 2023 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-37362418

RESUMEN

Purpose: To evaluate the cases of retinal vessel occlusion following COVID-19 vaccination and evaluate the onset interval and clinical presentations in patients diagnosed with vaccine associated retinal artery occlusion (RAO) and retinal vein occlusion (RVO). Design: Retrospective study of the cases reported to the Centers for Disease Control and Prevention (CDC) Vaccine Adverse Events Reporting System (VAERS) between December 11, 2020 and July 1, 2022. Participants: Patients diagnosed with retinal vessel occlusion following vaccination with BNT162b2, mRNA-1273, and Ad26.COV2.S globally. Methods: We performed a descriptive analysis of the patient demographics and clinical presentation in patients with retinal vessel occlusion. The correlation between the vaccines and continuous and categorical variables were assessed. We performed the post-hoc analysis to evaluated the association between RAO and RVO onset post-vaccination, and vaccine and dosage. Finally, a 30-day reverse analysis for RAO and RVO onset following administration of vaccine. A major limitation in the methods of this study is the lack of control group for assessing the risk of retinal vessel occlusive disease in patients who received the vaccine compared to the patients who were unvaccinated. Main Outcome Measures: The crude reporting rate of retinal vessel occlusion following SARS-CoV-2 vaccine. The ocular and systemic presentations, onset duration and short term risk of RAO and RVO following vaccination. Results: During the study period, 1351 retinal vessel occlusion cases were reported globally. The crude reporting rates of retinal vessel occlusion for BNT162b2, mRNA-1273, and Ad26.COV2.S were 0.36, 0.41, and 0.69, respectively. The majority of the retinal vessel occlusion cases were reported following BNT162b2 (n=606, 74.17%). The mean age of patients with RVO and RAO was 58.54 ± 16.06 years and 64.63 ± 16.16 years, respectively. In the cohort, 817 and 433 patients were diagnosed with RVO and RAO, respectively. Most cases of RVO (41.12%) and RAO (48.27%) were reported within the first week post-vaccination. We observed that the mean onset interval for RVO was significantly longer in patients who received Ad26.Cov2.S (54.07 ± 88.98 days) compared to BNT162b2 (18.07 ± 28.66 days) and mRNA-1273 (22.85 ± 38.13 days) vaccines (p<0.0001). This was further confirmed by post-hoc analysis, which revealed a significantly longer onset duration for the Ad26.Cov2.S compared to BNT162b2 and mRNA 1273 vaccines (p<0.0001). The reverse Kaplan Meier 30-day risk analysis showed a significant a higher risk of RVO onset following BNT162b2 compared to other vaccines(p<0.0001). Conclusions: The low crude reporting rate highlights a low safety concern for retinal vessel occlusion following SARS-CoV-2 vaccination. This study provides insights into possible temporal association between reported retinal vessel occlusion events with SARS-CoV-2 vaccines, however further insights are needed to understand the underlying immunopathological mechanisms that promote thrombosis of retinal vasculature on vaccine administration.

18.
mSystems ; 8(4): e0128022, 2023 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-37377419

RESUMEN

Stable isotope probing (SIP) facilitates culture-independent identification of active microbial populations within complex ecosystems through isotopic enrichment of nucleic acids. Many DNA-SIP studies rely on 16S rRNA gene sequences to identify active taxa, but connecting these sequences to specific bacterial genomes is often challenging. Here, we describe a standardized laboratory and analysis framework to quantify isotopic enrichment on a per-genome basis using shotgun metagenomics instead of 16S rRNA gene sequencing. To develop this framework, we explored various sample processing and analysis approaches using a designed microbiome where the identity of labeled genomes and their level of isotopic enrichment were experimentally controlled. With this ground truth dataset, we empirically assessed the accuracy of different analytical models for identifying active taxa and examined how sequencing depth impacts the detection of isotopically labeled genomes. We also demonstrate that using synthetic DNA internal standards to measure absolute genome abundances in SIP density fractions improves estimates of isotopic enrichment. In addition, our study illustrates the utility of internal standards to reveal anomalies in sample handling that could negatively impact SIP metagenomic analyses if left undetected. Finally, we present SIPmg, an R package to facilitate the estimation of absolute abundances and perform statistical analyses for identifying labeled genomes within SIP metagenomic data. This experimentally validated analysis framework strengthens the foundation of DNA-SIP metagenomics as a tool for accurately measuring the in situ activity of environmental microbial populations and assessing their genomic potential. IMPORTANCE Answering the questions, "who is eating what?" and "who is active?" within complex microbial communities is paramount for our ability to model, predict, and modulate microbiomes for improved human and planetary health. These questions can be pursued using stable isotope probing to track the incorporation of labeled compounds into cellular DNA during microbial growth. However, with traditional stable isotope methods, it is challenging to establish links between an active microorganism's taxonomic identity and genome composition while providing quantitative estimates of the microorganism's isotope incorporation rate. Here, we report an experimental and analytical workflow that lays the foundation for improved detection of metabolically active microorganisms and better quantitative estimates of genome-resolved isotope incorporation, which can be used to further refine ecosystem-scale models for carbon and nutrient fluxes within microbiomes.


Asunto(s)
Metagenómica , Microbiota , Humanos , Metagenómica/métodos , ARN Ribosómico 16S/genética , ADN/genética , Isótopos , Microbiota/genética
20.
Adv Drug Deliv Rev ; 187: 114361, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35636569

RESUMEN

Two-dimensional (2D) molybdenum disulfide (MoS2) is an ultrathin nanomaterial with a high degree of anisotropy, surface-to-volume ratio, chemical functionality and mechanical strength. These properties together enable MoS2 to emerge as a potent nanomaterial for diverse biomedical applications including drug delivery, regenerative medicine, biosensing and bioelectronics. Thus, understanding the interactions of MoS2 with its biological interface becomes indispensable. These interactions, referred to as "nano-bio" interactions, play a key role in determining the biocompatibility and the pathways through which the nanomaterial influences molecular, cellular and biological function. Herein, we provide a critical overview of the nano-bio interactions of MoS2 and emphasize on how these interactions dictate its biomedical applications including intracellular trafficking, biodistribution and biodegradation. Also, a critical evaluation of the interactions of MoS2 with proteins and specific cell types such as immune cells and progenitor/stem cells is illustrated which governs the short-term and long-term compatibility of MoS2-based biomedical devices.


Asunto(s)
Molibdeno , Nanoestructuras , Disulfuros/química , Humanos , Molibdeno/química , Nanoestructuras/química , Distribución Tisular
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