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1.
Histol Histopathol ; : 18684, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38088133

RESUMEN

Infertility is a growing challenge globally with emerging risk factors. There are effective laboratory tests to evaluate infertility in humans, nevertheless, some measures, especially histopathological evaluations, are invasive due to the pain inflicted when accessing the reproductive organs and obtaining samples; hence, their relevance may be limited in humans. However, these histopathological evaluations provide essential information on the etiopathogenesis of infertility and the likely mechanisms of action of potential therapeutic candidates. Also, non-invasive methods are available, such as the assay of testosterone in the blood and semen analysis, both of which are predictors of testicular functions. This review provides detailed information on the available histopathological investigations of infertility, such as qualitative and quantitative histopathological assessments of gonadal tissues, specific cell counts, and sperm morphology characterization, with a focus on the procedures, interpretation, and pathophysiological basis. Data from the literature revealed that histopathological examinations of the reproductive organs, as well as spermatozoa, are useful in understanding the pathogenesis of incident infertility. Histopathological evaluation may range from basic hematoxylin and eosin stains to some special stains. Also, histopathological findings (such as spermatogenic cells and planimetric variables, like seminiferous tubule diameter and theca cell and corpus luteum thickness) may be quantified and analyzed for comparison. Some skill is required for these investigations, which may be a limiting factor; however, they are important tools in translational medicine.

2.
JACC Case Rep ; 17: 101900, 2023 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-37496718

RESUMEN

A 62-year-old man experienced embolization of a patent foramen ovale (PFO) occlusion device in the pulmonary artery. The device was successfully retrieved using "puncture to loop" technique, without the need of specific materials. This is a challenging retrieval situation, confirming the feasibility and flexibility of the technique. (Level of Difficulty: Advanced.).

3.
J Exp Bot ; 74(10): 2944-2955, 2023 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-36882965

RESUMEN

The angiosperm genus Cuscuta lives as an almost achlorophyllous root- and leafless holoparasite and has therefore occupied scientists for more than a century. The 'evolution' of Cuscuta research started with early studies that established the phylogenetic framework for this unusual genus. It continued to produce groundbreaking cytological, morphological, and physiological insight throughout the second half of the 20th century and culminated in the last two decades in exciting discoveries regarding the molecular basis of Cuscuta parasitism that were facilitated by the modern 'omics' tools and traceable fluorescent marker technologies of the 21st century. This review will show how present activities are inspired by those past breakthroughs. It will describe significant milestones and recurring themes of Cuscuta research and connect these to the remaining as well as newly evolving questions and future directions in this research field that is expected to sustain its strong growth in the future.


Asunto(s)
Cuscuta , Filogenia
5.
New Phytol ; 237(6): 2493-2504, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36564969

RESUMEN

Agrobacterium tumefaciens microbe-associated molecular pattern elongation factor Tu (EF-Tu) is perceived by orthologs of the Arabidopsis immune receptor EFR activating pattern-triggered immunity (PTI) that causes reduced T-DNA-mediated transient expression. We altered EF-Tu in A. tumefaciens to reduce PTI and improved transformation efficiency. A robust computational pipeline was established to detect EF-Tu protein variation in a large set of plant bacterial species and identified EF-Tu variants from bacterial pathogen Pseudomonas syringae pv. tomato DC3000 that allow the pathogen to escape EFR perception. Agrobacterium tumefaciens strains were engineered to substitute EF-Tu with DC3000 variants and examined their transformation efficiency in plants. Elongation factor Tu variants with rarely occurred amino acid residues were identified within DC3000 EF-Tu that mitigates recognition by EFR. Agrobacterium tumefaciens strains were engineered by expressing DC3000 EF-Tu instead of native agrobacterial EF-Tu and resulted in decreased plant immunity detection. These engineered A. tumefaciens strains displayed an increased efficiency in transient expression in both Arabidopsis thaliana and Camelina sativa. The results support the potential application of these strains as improved vehicles to introduce transgenic alleles into members of the Brassicaceae family.


Asunto(s)
Agrobacterium tumefaciens , Proteínas de Arabidopsis , Arabidopsis , Técnicas de Transferencia de Gen , Factor Tu de Elongación Peptídica , Inmunidad de la Planta , Agrobacterium tumefaciens/genética , Agrobacterium tumefaciens/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Factor Tu de Elongación Peptídica/genética , Factor Tu de Elongación Peptídica/metabolismo , Inmunidad de la Planta/genética , Pseudomonas syringae/genética
6.
Eur J Cardiothorac Surg ; 62(3)2022 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-35920768

RESUMEN

The retrograde valve-crossing of a stenotic aortic valve is a crucial step in the transcatheter aortic valve implantation procedure. In addition to being time-consuming and associated with an increased stroke risk, inappropriate valve-crossing may cause devastating complications. This tutorial review summarizes systematic and detailed techniques to cross the aortic valve. First, the main challenges in retrograde valve-crossing are depicted. Next, a step-by-step guidance on valve-crossing is provided, along with an in-depth description of the three-dimensional anatomy under a two-dimensional fluoroscopy view. Finally, modified techniques for different anatomies are described.


Asunto(s)
Estenosis de la Válvula Aórtica , Prótesis Valvulares Cardíacas , Reemplazo de la Válvula Aórtica Transcatéter , Algoritmos , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/cirugía , Fluoroscopía , Humanos , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Resultado del Tratamiento
7.
J Card Surg ; 37(10): 3396-3402, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35842798

RESUMEN

We report the case of a 78-year-old female with Sapien 3 transcatheter heart valve implantation in the transcaval approach. In this setting, we describe the step-by-step management and technique of the transcaval transcatheter aortic valve implantation.


Asunto(s)
Estenosis de la Válvula Aórtica , Enfermedad de la Válvula Aórtica Bicúspide , Prótesis Valvulares Cardíacas , Reemplazo de la Válvula Aórtica Transcatéter , Anciano , Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/cirugía , Femenino , Humanos , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Resultado del Tratamiento
8.
J Clin Med ; 11(5)2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35268296

RESUMEN

The transcatheter aortic valve implantation (TAVI) treatment pathway is complex, leading to procedure-related delays. Dedicated TAVI coordinators can improve pathway efficiency. COORDINATE was a pilot observational prospective registry at three German centers that enrolled consecutive elective patients with severe aortic stenosis undergoing TAVI to investigate the impact a TAVI coordinator program. Pathway parameters and clinical outcomes were assessed before (control group) and after TAVI coordinator program implementation (intervention phase). The number of repeated diagnostics remained unchanged after implementation. Patients with separate hospitalizations for screening and TAVI had long delays, which increased after implementation (65 days pre- vs. 103 days post-implementation); hospitalizations combining these were more efficient. The mean time between TAVI and hospital discharge remained constant. Nurse (p = 0.001) and medical technician (p = 0.008) working hours decreased. Patient satisfaction increased, and more consistent/intensive contact between patients and staff was reported. TAVI coordinators provided more post-TAVI support, including discharge management. No adverse effects on post-procedure or 30-day outcomes were seen. This pilot suggests that TAVI coordinator programs may improve aspects of the TAVI pathway, including post-TAVI care and patient satisfaction, without compromising safety. These findings will be further investigated in the BENCHMARK registry.

9.
Nat Commun ; 13(1): 1294, 2022 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-35277499

RESUMEN

Activation of plant pattern-triggered immunity (PTI) relies on the recognition of microbe-derived structures, termed patterns, through plant-encoded surface-resident pattern recognition receptors (PRRs). We show that proteobacterial translation initiation factor 1 (IF1) triggers PTI in Arabidopsis thaliana and related Brassicaceae species. Unlike for most other immunogenic patterns, IF1 elicitor activity cannot be assigned to a small peptide epitope, suggesting that tertiary fold features are required for IF1 receptor activation. We have deployed natural variation in IF1 sensitivity to identify Arabidopsis leucine-rich repeat (LRR) receptor-like protein 32 (RLP32) as IF1 receptor using a restriction site-associated DNA sequencing approach. RLP32 confers IF1 sensitivity to rlp32 mutants, IF1-insensitive Arabidopsis accessions and IF1-insensitive Nicotiana benthamiana, binds IF1 specifically and forms complexes with LRR receptor kinases SOBIR1 and BAK1 to mediate signaling. Similar to other PRRs, RLP32 confers resistance to Pseudomonas syringae, highlighting an unexpectedly complex array of bacterial pattern sensors within a single plant species.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Factores Procarióticos de Iniciación , Receptores de Reconocimiento de Patrones , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Genotipo , Enfermedades de las Plantas/microbiología , Inmunidad de la Planta/genética , Proteobacteria/metabolismo , Pseudomonas syringae/metabolismo , Receptores de Reconocimiento de Patrones/genética , Receptores de Reconocimiento de Patrones/metabolismo
10.
J Anat ; 240(1): 84-93, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34427936

RESUMEN

Both the lumbar and tail intervertebral discs (IVD) of mice serve as models for the pathogenesis and histologic progression of degenerative disc disease. Recent studies in mature mice, however, demonstrate that the mechanics and physical attributes of lumbar and tail IVD-endplate (EP)-interfaces are strikingly different. We hypothesized that these structural disparities are associated with differences in the composition and organization of soft tissue elements that influence the biomechanical properties of the spine. Lumbar and tail vertebral segments and discs were collected from the same C57BL/6N and C57BL/6JRj mice, respectively for histological comparison of coronal sections at the ages of 4 weeks (weaned, both strains, C57BL/6N: n = 7; C57BL/6JRj: n = 4), three (mature, C57BL/6N: n = 7; C57BL/6JRj: n = 4), twelve (middle aged, C57BL/6JRj only: n = 3) and eighteen (old, C57BL/6JRj only: n = 3) months old. The histology of lumbar and tail IVD-EP-interfaces of mature mice differed markedly. The lumbar IVD-EP-interphase was characterized by a broad cartilaginous EP, while the tail IVD-EP-interphase comprised a thin layer of cartilage cells adjacent to a broad bony layer abutting the vertebral growth plate. Furthermore, the composition of the nuclei pulposi (NP) of lumbar and tail IVD in mature mice differed greatly. Lumbar NP consisted of a compact cluster of mainly large, uni-vacuolated cells centered in an amorphous matrix, while tail NP were composed of a loose aggregate of vacuolated and non-vacuolated cells. The anuli fibrosi also differed, with more abundant and sharply defined lamellae in tail compared to lumbar discs. The observed histological differences in the EP were even most prominent in weaned mice but were still discernible in middle-aged and old mice. An appreciation of the histological differences between lumbar and tail IVD components in mice, including nucleus pulposus, annulus fibrosus, and endplates, is essential to our understanding of spinal biomechanics in these animals and should inform the design and interpretation of future IVD-studies.


Asunto(s)
Degeneración del Disco Intervertebral , Disco Intervertebral , Núcleo Pulposo , Animales , Disco Intervertebral/patología , Degeneración del Disco Intervertebral/patología , Vértebras Lumbares/patología , Ratones , Ratones Endogámicos C57BL , Cola (estructura animal)
11.
Front Cardiovasc Med ; 8: 774047, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34796222

RESUMEN

The transcatheter heart valve (THV) embolization is a rare but challenging complication in transcatheter aortic valve implantation (TAVI). We report the case of an 81-year-old man with Sapien 3 embolization caused by interrupted rapid pacing. In this setting, we describe the embolized THV management and the technique of the second Sapien 3 implantation.

13.
Nat Plants ; 7(9): 1254-1263, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34326531

RESUMEN

Plant pattern recognition receptors (PRRs) facilitate recognition of microbial patterns and mediate activation of plant immunity. Arabidopsis thaliana RLP42 senses fungal endopolygalacturonases (PGs) and triggers plant defence through complex formation with SOBIR1 and SERK co-receptors. Here, we show that a conserved 9-amino-acid fragment pg9(At) within PGs is sufficient to activate RLP42-dependent plant immunity. Structure-function analysis reveals essential roles of amino acid residues within the RLP42 leucine-rich repeat and island domains for ligand binding and PRR complex assembly. Sensitivity to pg9(At), which is restricted to A. thaliana and exhibits scattered accession specificity, is unusual for known PRRs. Arabidopsis arenosa and Brassica rapa, two Brassicaceae species closely related to A. thaliana, respectively perceive immunogenic PG fragments pg20(Aa) and pg36(Bra), which are structurally distinct from pg9(At). Our study provides evidence for rapid evolution of polymorphic PG sensors with distinct pattern specificities within a single plant family.


Asunto(s)
Arabidopsis/genética , Arabidopsis/inmunología , Brassica/genética , Brassica/inmunología , Nicotiana/genética , Nicotiana/inmunología , Inmunidad de la Planta/genética , Poligalacturonasa/inmunología , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Variación Genética , Genotipo , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/inmunología , Plantas Modificadas Genéticamente , Poligalacturonasa/genética
14.
Commun Integr Biol ; 14(1): 111-114, 2021 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-33995821

RESUMEN

Cuscuta reflexa (giant dodder) is an obligate stem holoparasite withdrawing water, nutrients, and carbohydrates from its hosts. For a broad spectrum of host plants, C. reflexa usually stays unrecognized. The cultivated tomato Solanum lycopersicum, as one notable exception, possesses a leucine-rich repeat receptor protein (LRR-RP), Cuscuta receptor 1 (CuRe1), which enables tomato to recognize C. reflexa as a dangerous parasitic invader and to respond with plant immune responses. During the infection process, a glycine-rich protein (GRP) is freed from C. reflexa and gets detected by CuRe1. Here, we focus on the subcellular localization of the GRP within plant cell walls using a fluorescence based co-localization.

15.
Plant Physiol ; 185(4): 1282-1291, 2021 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-33793887

RESUMEN

Parasitic plants pose a major biotic threat to plant growth and development and lead to losses in crop productivity of billions of USD annually. By comparison with "normal" autotrophic plants, parasitic plants live a heterotrophic lifestyle and rely on water, solutes and to a greater (holoparasitic plants) or lesser extent (hemiparasitic plants) on sugars from other host plants. Most hosts are unable to detect an infestation by plant parasites or unable to fend off these parasitic invaders. However, a few hosts have evolved defense strategies to avoid infestation or protect themselves actively post-attack often leading to full or partial resistance. Here, we review the current state of our understanding of the defense strategies to plant parasitism used by host plants with emphasis on the active molecular resistance mechanisms. Furthermore, we outline the perspectives and the potential of future studies that will be indispensable to develop and breed resistant crops.


Asunto(s)
Productos Agrícolas/parasitología , Interacciones Huésped-Parásitos/fisiología , Enfermedades Parasitarias/inmunología , Inmunidad de la Planta/fisiología , Virulencia/fisiología , Estados Unidos
16.
Front Plant Sci ; 12: 635962, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33767719

RESUMEN

Complex N-glycan modification of secretory glycoproteins in plants is still not well understood. Essential in animals, where a lack of complex N-glycans is embryo-lethal, their presence in plants seemed less relevant for a long time mostly because Arabidopsis thaliana cgl1 mutants lacking N-acetyl-glucosaminyltransferase I (GNTI, the enzyme initiating complex N-glycan maturation in the Golgi apparatus) are viable and showed only minor impairments regarding stress tolerance or development. A different picture emerged when a rice (Oryza sativa) gntI T-DNA mutant was found to be unable to reach the reproductive stage. Here, we report on tomato (Solanum lycopersicum) lines that showed severe impairments upon two RNA interference (RNAi) approaches. Originally created to shed light on the role of core α1,3-fucose and ß1,2-xylose residues in food allergy, plants with strongly reduced GNTI activity developed necrotic fruit-attached stalks and early fruit drop combined with patchy incomplete ripening. Correspondingly, semiquantitative RT-PCR of the abscission zone (az) revealed an increase of abscission markers. Also, GNTI-RNA interference (RNAi) plants were more susceptible to sporadic infection. To obtain vital tomatoes with comparable low allergenic potential, Golgi α-mannosidase II (MANII) was chosen as the second target. The resulting phenotypes were oppositional: MANII-reduced plants carried normal-looking fruits that remained attached for extended time without signs of necrosis. Fruits contained no or only few, but enlarged, seeds. Furthermore, leaves developed rolled-up rims simultaneously during the reproductive stage. Trials to cross MANII-reduced plants failed, while GNTI-reduced plants could be (back-)crossed, retaining their characteristic phenotype. This phenotype could not be overcome by ethephon or indole-3-acetic acid (IAA) application, but the latter was able to mimic patchy fruit ripening in wild-type. Phytohormones measured in leaves and 1-aminocyclopropane-1-carboxylic acid (ACC) contents in fruits showed no significant differences. Together, the findings hint at altered liberation/perception of protein-bound N-glycans, known to trigger auxin-like effects. Concomitantly, semiquantitative RT-PCR analysis revealed differences in auxin-responsive genes, indicating the importance of complex N-glycan modification for hormone signaling/crosstalk. Another possible role of altered glycoprotein life span seems subordinate, as concluded from transient expression of Arabidopsis KORRIGAN KOR1-GFP fusion proteins in RNAi plants of Nicotiana benthamiana. In summary, our analyses stress the importance of complex N-glycan maturation for normal plant responses, especially in fruit-bearing crops like tomato.

17.
JACC Asia ; 1(2): 147-161, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36338163

RESUMEN

Bicuspid aortic valve (BAV) remains challenging in transcatheter aortic valve replacement (TAVR) because of unfavorable anatomy. New-generation balloon-expandable valve (BEV) appears to be a valid alternative to surgery, especially in some Asian countries with a higher prevalence of BAV. This tutorial review summarizes current thinking about how to plan and implant BEV in BAVs using versatile techniques. First, the authors depict the main morphological characteristics of BAVs and their effects on the TAVR procedure. Next, the authors provide preprocedural analysis on sizing, obtaining the optimal deployment projection, and how to simplify valve-crossing. Finally, the authors provide step-by-step guidance on how to deploy the BEVs with evolved iterations in terms of specific anatomies, calcified annulus, and giant annulus.

18.
Nat Commun ; 11(1): 5299, 2020 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-33082345

RESUMEN

Parasitic plants of the genus Cuscuta penetrate shoots of host plants with haustoria and build a connection to the host vasculature to exhaust water, solutes and carbohydrates. Such infections usually stay unrecognized by the host and lead to harmful host plant damage. Here, we show a molecular mechanism of how plants can sense parasitic Cuscuta. We isolated an 11 kDa protein of the parasite cell wall and identified it as a glycine-rich protein (GRP). This GRP, as well as its minimal peptide epitope Crip21, serve as a pathogen-associated molecular pattern and specifically bind and activate a membrane-bound immune receptor of tomato, the Cuscuta Receptor 1 (CuRe1), leading to defense responses in resistant hosts. These findings provide the initial steps to understand the resistance mechanisms against parasitic plants and further offer great potential for protecting crops by engineering resistance against parasitic plants.


Asunto(s)
Pared Celular/metabolismo , Cuscuta/metabolismo , Enfermedades de las Plantas/parasitología , Proteínas de Plantas/metabolismo , Solanum lycopersicum/metabolismo , Solanum lycopersicum/parasitología , Pared Celular/genética , Cuscuta/genética , Regulación de la Expresión Génica de las Plantas , Interacciones Huésped-Parásitos , Solanum lycopersicum/genética , Enfermedades de las Plantas/genética , Proteínas de Plantas/genética
19.
Nat Plants ; 6(9): 1074-1075, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32879434
20.
Nat Plants ; 6(1): 22-27, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31949311

RESUMEN

Bacterial flagella are perceived by the innate immune systems of plants1 and animals2 alike, triggering resistance. Common to higher plants is the immunoreceptor FLAGELLIN-SENSING 2 (FLS2)3, which detects flagellin via its most conserved epitope, flg22. Agrobacterium tumefaciens, which causes crown gall disease in many crop plants, has a highly diverged flg22 epitope and evades immunodetection by plants so far studied. We asked whether, as a next step in this game of 'hide and seek', there are plant species that have evolved immunoreceptors with specificity for the camouflaged flg22Atum of A. tumefaciens. In the wild grape species Vitis riparia, we discovered FLS2XL, a previously unknown form of FLS2, that provides exquisite sensitivity to typical flg22 and to flg22Atum. As exemplified by ectopic expression in tobacco, FLS2XL can limit crown gall disease caused by A. tumefaciens.


Asunto(s)
Agrobacterium tumefaciens/fisiología , Flagelina/metabolismo , Proteínas de Plantas/metabolismo , Tumores de Planta/microbiología , Proteínas Quinasas/metabolismo , Vitis/metabolismo , Vitis/microbiología
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