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1.
EMBO Rep ; 25(4): 1987-2014, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38454158

RESUMEN

α-Melanocyte-stimulating hormone (α-MSH) regulates diverse physiological functions by activating melanocortin receptors (MC-R). However, the role of α-MSH and its possible target receptors in the heart remain completely unknown. Here we investigate whether α-MSH could be involved in pathological cardiac remodeling. We found that α-MSH was highly expressed in the mouse heart with reduced ventricular levels after transverse aortic constriction (TAC). Administration of a stable α-MSH analog protected mice against TAC-induced cardiac hypertrophy and systolic dysfunction. In vitro experiments revealed that MC5-R in cardiomyocytes mediates the anti-hypertrophic signaling of α-MSH. Silencing of MC5-R in cardiomyocytes induced hypertrophy and fibrosis markers in vitro and aggravated TAC-induced cardiac hypertrophy and fibrosis in vivo. Conversely, pharmacological activation of MC5-R improved systolic function and reduced cardiac fibrosis in TAC-operated mice. In conclusion, α-MSH is expressed in the heart and protects against pathological cardiac remodeling by activating MC5-R in cardiomyocytes. These results suggest that analogs of naturally occurring α-MSH, that have been recently approved for clinical use and have agonistic activity at MC5-R, may be of benefit in treating heart failure.


Asunto(s)
Remodelación Ventricular , alfa-MSH , Ratones , Animales , alfa-MSH/farmacología , Receptores de Corticotropina , Receptores de Melanocortina , Cardiomegalia/genética , Fibrosis
2.
Proc Natl Acad Sci U S A ; 120(21): e2216573120, 2023 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-37186854

RESUMEN

Declines in European bird populations are reported for decades but the direct effect of major anthropogenic pressures on such declines remains unquantified. Causal relationships between pressures and bird population responses are difficult to identify as pressures interact at different spatial scales and responses vary among species. Here, we uncover direct relationships between population time-series of 170 common bird species, monitored at more than 20,000 sites in 28 European countries, over 37 y, and four widespread anthropogenic pressures: agricultural intensification, change in forest cover, urbanisation and temperature change over the last decades. We quantify the influence of each pressure on population time-series and its importance relative to other pressures, and we identify traits of most affected species. We find that agricultural intensification, in particular pesticides and fertiliser use, is the main pressure for most bird population declines, especially for invertebrate feeders. Responses to changes in forest cover, urbanisation and temperature are more species-specific. Specifically, forest cover is associated with a positive effect and growing urbanisation with a negative effect on population dynamics, while temperature change has an effect on the dynamics of a large number of bird populations, the magnitude and direction of which depend on species' thermal preferences. Our results not only confirm the pervasive and strong effects of anthropogenic pressures on common breeding birds, but quantify the relative strength of these effects stressing the urgent need for transformative changes in the way of inhabiting the world in European countries, if bird populations shall have a chance of recovering.


Asunto(s)
Agricultura , Bosques , Animales , Granjas , Europa (Continente) , Dinámica Poblacional , Aves/fisiología , Biodiversidad , Ecosistema , Conservación de los Recursos Naturales
3.
Am J Physiol Cell Physiol ; 326(5): C1437-C1450, 2024 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-38525542

RESUMEN

Plasma apelin levels are reduced in aging and muscle wasting conditions. We aimed to investigate the significance of apelin signaling in cardiac and skeletal muscle responses to physiological stress. Apelin knockout (KO) and wild-type (WT) mice were subjected to high-intensity interval training (HIIT) by treadmill running. The effects of apelin on energy metabolism were studied in primary mouse skeletal muscle myotubes and cardiomyocytes. Apelin increased mitochondrial ATP production and mitochondrial coupling efficiency in myotubes and promoted the expression of mitochondrial genes both in primary myotubes and cardiomyocytes. HIIT induced mild concentric cardiac hypertrophy in WT mice, whereas eccentric growth was observed in the left ventricles of apelin KO mice. HIIT did not affect myofiber size in skeletal muscles of WT mice but decreased the myofiber size in apelin KO mice. The decrease in myofiber size resulted from a fiber type switch toward smaller slow-twitch type I fibers. The increased proportion of slow-twitch type I fibers in apelin KO mice was associated with upregulation of myosin heavy chain slow isoform expression, accompanied with upregulated expression of genes related to fatty acid transport and downregulated expression of genes related to glucose metabolism. Mechanistically, skeletal muscles of apelin KO mice showed defective induction of insulin-like growth factor-1 signaling in response to HIIT. In conclusion, apelin is required for proper skeletal and cardiac muscle adaptation to high-intensity exercise. Promoting apelinergic signaling may have benefits in aging- or disease-related muscle wasting conditions.NEW & NOTEWORTHY Apelin levels decline with age. This study demonstrates that in trained mice, apelin deficiency results in a switch from fast type II myofibers to slow oxidative type I myofibers. This is associated with a concomitant change in gene expression profile toward fatty acid utilization, indicating an aged-muscle phenotype in exercised apelin-deficient mice. These data are of importance in the design of exercise programs for aging individuals and could offer therapeutic target to maintain muscle mass.


Asunto(s)
Adaptación Fisiológica , Apelina , Ratones Noqueados , Músculo Esquelético , Condicionamiento Físico Animal , Animales , Apelina/metabolismo , Apelina/genética , Ratones , Condicionamiento Físico Animal/fisiología , Músculo Esquelético/metabolismo , Entrenamiento de Intervalos de Alta Intensidad/métodos , Masculino , Miocitos Cardíacos/metabolismo , Metabolismo Energético , Ratones Endogámicos C57BL , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares de Contracción Lenta/metabolismo , Cardiomegalia/metabolismo , Cardiomegalia/genética , Cardiomegalia/fisiopatología , Cardiomegalia/patología
4.
Chemistry ; : e202402409, 2024 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-39183180

RESUMEN

Complex dynamic systems displaying interdependency between nitroaldol and boronic ester reactions have been demonstrated. Nitroalkane-1,3-diols, generated by the nitroaldol reaction, were susceptible to ester formation with different boronic acids in aprotic solvents, whereas hydrolysis of the esters occurred in the presence of water. The boronic ester formation led to significant stabilization of the nitroaldol adducts under basic conditions. The use of bifunctional building blocks was furthermore established, allowing for main chain nitroaldol-boronate dynamers as well as complex network dynamers with distinct topologies. The shape and rigidity of the resulting dynamers showed an apparent dependency on the configuration of the boronic acids.

5.
Environ Sci Technol ; 58(42): 18822-18833, 2024 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-39394040

RESUMEN

Stream salinization is a global issue, yet few models can provide reliable salinity estimates for unmonitored locations at the time scales required for ecological exposure assessments. Machine learning approaches are presented that use spatially limited high-frequency monitoring and spatially distributed discrete samples to estimate the daily stream-specific conductance across a watershed. We compare the predictive performance of space- and time-unaware Random Forest models and space- and time-aware Recurrent Graph Convolution Neural Network models (KGE: 0.67 and 0.64, respectively) and use explainable artificial intelligence methods to interpret model predictions and understand salinization drivers. These models are applied to the Delaware River Basin, a developed watershed with diverse land uses that experiences anthropogenic salinization from winter deicer applications. These models capture seasonality for the winter first flush of deicers, and the streams with elevated predictions correspond well with indicators of deicer application. This result suggests that these models can be used to identify potential salinity-impaired streams for winter best management practices. Daily salinity predictions are driven primarily by land cover (urbanization) trends that may represent anthropogenic salinization processes and weather at time scales up to three months. Such modeling approaches are likely transferable to other watersheds and can be applied to further understand salinization risks and drivers.


Asunto(s)
Aprendizaje Automático , Ríos , Salinidad , Ríos/química , Monitoreo del Ambiente/métodos , Estaciones del Año , Redes Neurales de la Computación
6.
Biomed Eng Online ; 23(1): 13, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38297359

RESUMEN

BACKGROUND: Turning in place is a challenging motor task and is used as a brief assessment test of lower limb function and dynamic balance. This review aims to examine how research of instrumented analysis of turning in place is implemented. In addition to reporting the studied population, we covered acquisition systems, turn detection methods, quantitative parameters, and how these parameters are computed. METHODS: Following the development of a rigorous search strategy, the Web of Science and Scopus were systematically searched for studies involving the use of turning-in-place. From the selected articles, the study population, types of instruments used, turn detection method, and how the turning-in-place characteristics were calculated. RESULTS: Twenty-one papers met the inclusion criteria. The subject groups involved in the reviewed studies included young, middle-aged, and older adults, stroke, multiple sclerosis and Parkinson's disease patients. Inertial measurement units (16 studies) and motion camera systems (5 studies) were employed for gathering measurement data, force platforms were rarely used (2 studies). Two studies used commercial software for turn detection, six studies referenced previously published algorithms, two studies developed a custom detector, and eight studies did not provide any details about the turn detection method. The most frequently used parameters were mean angular velocity (14 cases, 7 studies), turn duration (13 cases, 13 studies), peak angular velocity (8 cases, 8 studies), jerkiness (6 cases, 5 studies) and freezing-of-gait ratios (5 cases, 5 studies). Angular velocities were derived from sensors placed on the lower back (7 cases, 4 studies), trunk (4 cases, 2 studies), and shank (2 cases, 1 study). The rest (9 cases, 8 studies) did not report sensor placement. Calculation of the freezing-of-gait ratio was based on the acceleration of the lower limbs in all cases. Jerkiness computation employed acceleration in the medio-lateral (4 cases) and antero-posterior (1 case) direction. One study did not reported any details about jerkiness computation. CONCLUSION: This review identified the capabilities of turning-in-place assessment in identifying movement differences between the various subject groups. The results, based on data acquired by inertial measurement units across studies, are comparable. A more in-depth analysis of tests developed for gait, which has been adopted in turning-in-place, is needed to examine their validity and accuracy.


Asunto(s)
Enfermedad de Parkinson , Accidente Cerebrovascular , Persona de Mediana Edad , Humanos , Anciano , Marcha , Movimiento , Pierna
7.
Int J Mol Sci ; 25(3)2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38338841

RESUMEN

Human tear fluid contains numerous compounds, which are present in highly variable amounts owing to the dynamic and multipurpose functions of tears. A better understanding of the level and sources of variance is essential for determining the functions of the different tear components and the limitations of tear samples as a potential biomarker source. In this study, a quantitative proteomic method was used to analyze variations in the tear protein profiles of healthy volunteers. High day-to-day and inter-eye personal variances were observed in the tear volumes, protein content, and composition of the tear samples. Several normalization and outlier exclusion approaches were evaluated to decrease variances. Despite the intrapersonal variances, statistically significant differences and cluster analysis revealed that proteome profile and immunoglobulin composition of tear fluid present personal characteristics. Using correlation analysis, we could identify several correlating protein clusters, mainly related to the source of the proteins. Our study is the first attempt to achieve more insight into the biochemical background of human tears by statistical evaluation of the experimentally observed dynamic behavior of the tear proteome. As a pilot study for determination of personal protein profiles of the tear fluids of individual patients, it contributes to the application of this noninvasively collectible body fluid in personal medicine.


Asunto(s)
Proteoma , Proteómica , Humanos , Proteoma/metabolismo , Proteómica/métodos , Proyectos Piloto , Lágrimas/metabolismo , Proteínas del Ojo/metabolismo , Control de Calidad
8.
Int J Mol Sci ; 25(19)2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39408903

RESUMEN

The enantioselective binding of three proton pump inhibitors (PPIs)-omeprazole, rabeprazole, and lansoprazole-to two key plasma proteins, α1-acid glycoprotein (AGP) and human serum albumin (HSA), was characterized. The interactions between PPI enantiomers and proteins were investigated using a multifaceted analytical approach, including high-performance liquid chromatography (HPLC), fluorescence and UV spectroscopy, as well as in silico molecular docking. HPLC analysis demonstrated that all three PPIs exhibited enantioseparation on an AGP-based chiral stationary phase, suggesting stereoselective binding to AGP, while only lansoprazole showed enantioselective binding on the HSA-based column. Quantitatively, the S-enantiomers of omeprazole and rabeprazole showed higher binding affinity to AGP, while the R-enantiomer of lansoprazole displayed greater affinity for AGP, with a reversal in the elution order observed between the two protein-based columns. Protein binding percentages, calculated via HPLC, were greater than 88% for each enantiomer across both transport proteins, with all enantiomers displaying higher affinity for AGP compared to HSA. Thermodynamic analysis indicated that on the HSA, the more common, enthalpy-controlled enantioseparation was found, while in contrast, on the AGP, entropy-controlled enantioseparation was observed. The study also identified limitations in using fluorescence titration due to the high native fluorescence of the compounds, whereas UV titration was effective for both proteins. The determined logK values were in the range of 4.47-4.83 for AGP and 4.02-4.66 for HSA. Molecular docking supported the experimental findings by revealing the atomic interactions driving the binding process, with the predicted enantiomer elution orders aligning with experimental data. The comprehensive use of these analytical methods provides detailed insights into the enantioselective binding properties of PPIs, contributing to the understanding of their pharmacokinetic differences and aiding in the development of more effective therapeutic strategies.


Asunto(s)
Simulación del Acoplamiento Molecular , Orosomucoide , Unión Proteica , Inhibidores de la Bomba de Protones , Albúmina Sérica Humana , Humanos , Orosomucoide/química , Orosomucoide/metabolismo , Inhibidores de la Bomba de Protones/química , Inhibidores de la Bomba de Protones/metabolismo , Estereoisomerismo , Cromatografía Líquida de Alta Presión/métodos , Albúmina Sérica Humana/química , Albúmina Sérica Humana/metabolismo , Termodinámica , Omeprazol/química , Omeprazol/metabolismo , Rabeprazol/química , Rabeprazol/metabolismo , Espectrometría de Fluorescencia
9.
Int J Mol Sci ; 25(5)2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38473945

RESUMEN

A reversed-phase high-performance liquid chromatographic (HPLC) method was developed for the simultaneous determination of the potential impurities of dexketoprofen, including the distomer R-ketoprofen. After screening the separation capability of four polysaccharide columns (Lux Amylose-1, Lux Amylose-2, Lux Cellulose-1 and Lux Cellulose-2) in polar organic and in reversed-phase modes, appropriate enantioseparation was observed only on the Lux Amylose-2 column in an acidified acetonitrile/water mixture. A detailed investigation of the mobile phase composition and temperature for enantio- and chemoselectivity showed many unexpected observations. It was observed that both the resolution and the enantiomer elution order can be fine-tuned by varying the temperature and mobile phase composition. Moreover, hysteresis of the retention times and enantioselectivity was also observed in reversed-phase mode using methanol/water mixtures on amylose-type columns. This could indicate that the three-dimensional structure of the amylose column can change by transitioning from a polar organic to a reversed-phase mode, which affects the enantioseparation process. Temperature-dependent enantiomer elution order and rare enthalpic/entropic controlled enantioseparation in the operative temperature range were also observed in reversed-phase mode. To find the best methodological conditions for the determination of dexketoprofen impurities, a full factorial optimization design was performed. Using the optimized parameters (Lux Amylose-2 column with water/acetonitrile/acetic acid 50/50/0.1 (v/v/v) at a 1 mL/min flow rate at 20 °C), baseline separations were achieved between all compounds within 15 min. Our newly developed HPLC method was validated according to the current guidelines, and its application was tested on commercially available pharmaceutical formulations. According to the authors' knowledge, this is the first study to report hysteretic behavior on polysaccharide columns in reversed-phase mode.


Asunto(s)
Amilosa , Cromatografía de Fase Inversa , Cetoprofeno/análogos & derivados , Trometamina , Amilosa/química , Temperatura , Polisacáridos/química , Celulosa/química , Cromatografía Líquida de Alta Presión/métodos , Agua , Acetonitrilos , Estereoisomerismo
10.
Int J Mol Sci ; 25(13)2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-39000486

RESUMEN

In systemic sclerosis (SSc), fibrosis of the myocardium along with ongoing autoimmune inflammation can alter the electric function of the cardiac myocytes, which may increase the risk for ventricular arrhythmias and sudden cardiac death. We analyzed the electrocardiographic (ECG) variables describing ventricular repolarization such as QT interval, QT dispersion (QTd), T wave peak-to-end interval (Tpe), and arrhythmogeneity index (AIX) of 26 patients with SSc and 36 healthy controls. Furthermore, echocardiographic and laboratory parameters were examined, with a focus on inflammatory proteins like C-reactive ptotein (CRP), soluble intracellular adhesion molecule-1 (sICAM-1), soluble vascular adhesion molecule-1 (sVCAM-1), and progranulin (PGRN). The CRP, sICAM-1, and sVCAM-1 levels were positively correlated with the length of the QT interval. Although the serum PGRN levels were not increased in the SSc group compared to the controls, in SSc patients, the PGRN levels were positively correlated with the QT interval and the AIX. According to our results, we conclude that there may be a potential association between autoimmune inflammation and the risk for ventricular arrhythmias in patients with SSc. We emphasize that the measurement of laboratory parameters of inflammatory activity including CRP, PGRN, sVCAM-1, and sICAM-1 could be helpful in the prediction of sudden cardiac death in patients with SSc.


Asunto(s)
Arritmias Cardíacas , Molécula 1 de Adhesión Intercelular , Progranulinas , Esclerodermia Sistémica , Molécula 1 de Adhesión Celular Vascular , Humanos , Esclerodermia Sistémica/sangre , Esclerodermia Sistémica/complicaciones , Femenino , Masculino , Persona de Mediana Edad , Molécula 1 de Adhesión Celular Vascular/sangre , Molécula 1 de Adhesión Intercelular/sangre , Arritmias Cardíacas/etiología , Arritmias Cardíacas/sangre , Progranulinas/sangre , Electrocardiografía , Adulto , Biomarcadores/sangre , Estudios de Casos y Controles , Anciano , Factores de Riesgo , Proteína C-Reactiva/metabolismo , Proteína C-Reactiva/análisis
11.
Int J Mol Sci ; 25(9)2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38732202

RESUMEN

Acquiring resistance against antiviral drugs is a significant problem in antimicrobial therapy. In order to identify novel antiviral compounds, the antiviral activity of eight plants indigenous to the southern region of Hungary against herpes simplex virus-2 (HSV-2) was investigated. The plant extracts and the plant compound carnosic acid were tested for their effectiveness on both the extracellular and intracellular forms of HSV-2 on Vero and HeLa cells. HSV-2 replication was measured by a direct quantitative PCR (qPCR). Among the tested plant extracts, Salvia rosmarinus (S. rosmarinus) exhibited a 90.46% reduction in HSV-2 replication at the 0.47 µg/mL concentration. Carnosic acid, a major antimicrobial compound found in rosemary, also demonstrated a significant dose-dependent inhibition of both extracellular and intracellular forms of HSV-2. The 90% inhibitory concentration (IC90) of carnosic acid was between 25 and 6.25 µg/mL. Proteomics and high-resolution respirometry showed that carnosic acid suppressed key ATP synthesis pathways such as glycolysis, citrate cycle, and oxidative phosphorylation. Inhibition of oxidative phosphorylation also suppressed HSV-2 replication up to 39.94-fold. These results indicate that the antiviral action of carnosic acid includes the inhibition of ATP generation by suppressing key energy production pathways. Carnosic acid holds promise as a potential novel antiviral agent against HSV-2.


Asunto(s)
Abietanos , Adenosina Trifosfato , Antivirales , Herpesvirus Humano 2 , Extractos Vegetales , Replicación Viral , Abietanos/farmacología , Replicación Viral/efectos de los fármacos , Chlorocebus aethiops , Células Vero , Adenosina Trifosfato/metabolismo , Adenosina Trifosfato/biosíntesis , Humanos , Animales , Herpesvirus Humano 2/efectos de los fármacos , Herpesvirus Humano 2/fisiología , Antivirales/farmacología , Extractos Vegetales/farmacología , Extractos Vegetales/química , Células HeLa
12.
Molecules ; 29(6)2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38542982

RESUMEN

This comprehensive review explores the utilization of chiral stationary phases (CSPs) in the context of single-column simultaneous chiral-achiral high-performance liquid chromatography (HPLC) separation methods. While CSPs have traditionally been pivotal for enantioselective drug analysis, contemporary CSPs often exhibit notable chemoselective properties. Consequently, there is a discernible trend towards the development of methodologies that enable simultaneous enantio- and chemoselective separations utilizing a single CSP-based chromatographic column. This review provides an exhaustive overview of reported HPLC methods in this domain, with a focus on four major CSP types: cyclodextrin-, glycopeptide antibiotic-, protein-, and polysaccharide-based CSPs. This article delves into the diverse applications of CSPs, encompassing various chromatographic modes such as normal phase (NP), reverse phase (RP), and polar organic (PO). This review critically discusses method development, emphasizing the additional chemoselective separation mechanisms of CSPs. It also explores possibilities for method optimization and development, concluding with future perspectives on this evolving field. Despite the inherent challenges in understanding the retention mechanisms involved in chemoselective separations, this review highlights promising trends and anticipates a growing number of simultaneous enantio- and chemoselective methods in pharmaceutical analyses, pharmacokinetic studies, and environmental sample determinations.


Asunto(s)
Antibacterianos , Ciclodextrinas , Cromatografía Líquida de Alta Presión/métodos , Antibacterianos/química , Glicopéptidos/química , Estereoisomerismo
13.
Angew Chem Int Ed Engl ; : e202410435, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39329252

RESUMEN

Current methods for proteomimetic engineering rely on structure-based design. Here we describe a design strategy that allows the construction of proteomimetics against challenging targets without a priori characterization of the target surface. Our approach relies on (i) a 100-membered photoreactive foldamer library, the members of which act as local surface mimetics, and (ii) the subsequent affinity maturation of the primary hits using systems chemistry. Two surface-oriented proteinogenic side chains drove the interactions between the short helical foldamer fragments and the proteins. Diazirine-based photo-crosslinking was applied to sensitively detected and localize binding even to shallow and dynamic patches on representatively difficult targets. Photo-foldamers identified functionally relevant protein interfaces, allosteric and previously unexplored targetable regions on the surface of STAT3 and an oncogenic K-Ras variant. Target-templated dynamic linking of foldamer hits resulted in two orders of magnitude affinity improvement in a single step. The dimeric K-Ras ligand mimicked protein-like catalytic functions. The photo-foldamer approach thus enables the highly efficient mapping of protein-protein interaction sites and provides a viable starting point for proteomimetic ligand development without a priori structural hypotheses.

14.
J Am Chem Soc ; 145(21): 11818-11828, 2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37196315

RESUMEN

Many enzymes use adaptive frameworks to preorganize substrates, accommodate various structural and electronic demands of intermediates, and accelerate related catalysis. Inspired by biological systems, a Ru-based molecular water oxidation catalyst containing a configurationally labile ligand [2,2':6',2″-terpyridine]-6,6″-disulfonate was designed to mimic enzymatic framework, in which the sulfonate coordination is highly flexible and functions as both an electron donor to stabilize high-valent Ru and a proton acceptor to accelerate water dissociation, thus boosting the catalytic water oxidation performance thermodynamically and kinetically. The combination of single-crystal X-ray analysis, various temperature NMR, electrochemical techniques, and DFT calculations was utilized to investigate the fundamental role of the self-adaptive ligand, demonstrating that the on-demand configurational changes give rise to fast catalytic kinetics with a turnover frequency (TOF) over 2000 s-1, which is compared to oxygen-evolving complex (OEC) in natural photosynthesis.

15.
New Phytol ; 239(5): 1974-1988, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37381081

RESUMEN

In the nodules of IRLC legumes, including Medicago truncatula, nitrogen-fixing rhizobia undergo terminal differentiation resulting in elongated and endoreduplicated bacteroids specialized for nitrogen fixation. This irreversible transition of rhizobia is mediated by host produced nodule-specific cysteine-rich (NCR) peptides, of which c. 700 are encoded in the M. truncatula genome but only few of them have been proved to be essential for nitrogen fixation. We carried out the characterization of the nodulation phenotype of three ineffective nitrogen-fixing M. truncatula mutants using confocal and electron microscopy, monitored the expression of defence and senescence-related marker genes, and analysed the bacteroid differentiation with flow cytometry. Genetic mapping combined with microarray- or transcriptome-based cloning was used to identify the impaired genes. Mtsym19 and Mtsym20 mutants are defective in the same peptide NCR-new35 and the lack of NCR343 is responsible for the ineffective symbiosis of NF-FN9363. We found that the expression of NCR-new35 is significantly lower and limited to the transition zone of the nodule compared with other crucial NCRs. The fluorescent protein-tagged version of NCR343 and NCR-new35 localized to the symbiotic compartment. Our discovery added two additional members to the group of NCR genes essential for nitrogen-fixing symbiosis in M. truncatula.


Asunto(s)
Medicago truncatula , Rhizobium , Medicago truncatula/genética , Medicago truncatula/metabolismo , Cisteína/metabolismo , Nitrógeno/metabolismo , Péptidos/metabolismo , Fijación del Nitrógeno , Simbiosis , Nódulos de las Raíces de las Plantas/metabolismo
16.
Theor Appl Genet ; 136(3): 64, 2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36943531

RESUMEN

KEY MESSAGE: The bs5 resistance gene against bacterial spot was identified by map-based cloning. The recessive bs5 gene of pepper (Capsicum annuum L.) conditions a non-hypersensitive resistance trait, characterized by a slightly swollen, pale green, photosynthetically active leaf tissue, following Xanthomonas euvesicatoria infection. The isolation of the bs5 gene by map-based cloning revealed that the bs5 protein was shorter by 2 amino acids as compared to the wild type Bs5 protein. The natural 2 amino acid deletion occurred in the cysteine-rich transmembrane domain of the tail-anchored (TA) protein, Ca_CYSTM1. The protein products of the wild type Bs5 and mutant bs5 genes were shown to be located in the cell membrane, indicating an unknown function in this membrane compartment. Successful infection of the Bs5 pepper lines was abolished by the 6 bp deletion in the TM encoding domain of the Ca_CYSTM1 gene in bs5 homozygotes, suggesting, that the resulting resistance might be explained by the lack of entry of the Xanthomonas specific effector molecules into the plant cells.


Asunto(s)
Capsicum , Xanthomonas , Capsicum/genética , Capsicum/metabolismo , Alelos , Genes Recesivos , Membrana Celular/metabolismo , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/genética , Regulación de la Expresión Génica de las Plantas
17.
FASEB J ; 36(10): e22544, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36098469

RESUMEN

Wnt11 regulates early cardiac development and left ventricular compaction in the heart, but it is not known how Wnt11 regulates postnatal cardiac maturation and response to cardiac stress in the adult heart. We studied cell proliferation/maturation in postnatal and adolescent Wnt11 deficient (Wnt11-/-) heart and subjected adult mice with partial (Wnt11+/-) and complete Wnt11 (Wnt11-/-) deficiency to cardiac pressure overload. In addition, we subjected primary cardiomyocytes to recombinant Wnt proteins to study their effect on cardiomyocyte growth. Wnt11 deficiency did not affect cardiomyocyte proliferation or maturation in the postnatal or adolescent heart. However, Wnt11 deficiency led to enlarged heart phenotype that was not accompanied by significant hypertrophy of individual cardiomyocytes. Analysis of stressed adult hearts from wild-type mice showed a progressive decrease in Wnt11 expression in response to pressure overload. When studied in experimental cardiac pressure overload, Wnt11 deficiency did not exacerbate cardiac hypertrophy or remodeling and cardiac function remained identical between the genotypes. When subjecting cardiomyocytes to hypertrophic stimulus, the presence of recombinant Wnt11 together with Wnt5a reduced protein synthesis. In conclusion, Wnt11 deficiency does not affect postnatal cardiomyocyte proliferation but leads to cardiac growth. Interestingly, Wnt11 deficiency alone does not substantially modulate hypertrophic response to pressure overload in vivo. Wnt11 may require cooperation with other noncanonical Wnt proteins to regulate hypertrophic response under stress.


Asunto(s)
Corazón/crecimiento & desarrollo , Miocitos Cardíacos/metabolismo , Proteínas Wnt/metabolismo , Animales , Cardiomegalia/metabolismo , Proliferación Celular , Ratones , Miocardio , Proteínas Wnt/genética
18.
Vet Pathol ; 60(3): 320-323, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36869824

RESUMEN

Pituitary tumors are rare in chinchillas. This report describes the clinical, gross, histologic, and immunohistochemical characteristics of pituitary tumors in 4 chinchillas. The affected chinchillas were females between 4 and 18 years of age. Clinically, neurologic signs were most commonly reported and included depression, obtundation, seizure, head-pressing, ataxia, and possible blindness. Computed tomography scanning of 2 chinchillas revealed solitary intracranial extra-axial masses in the region of the pituitary gland. Two pituitary tumors were confined to the pars distalis; the other 2 invaded the brain. Based on their microscopic appearances and lack of distant metastases, all 4 tumors were diagnosed as pituitary adenomas. Immunohistochemically, all pituitary adenomas were weakly to strongly positive for growth hormone, most consistent with the diagnosis of somatotropic pituitary adenomas. To the authors' knowledge, this is the first detailed report of the clinical, pathologic, and immunohistochemical features of pituitary tumors in chinchillas.


Asunto(s)
Adenoma , Neoplasias Hipofisarias , Enfermedades de los Roedores , Femenino , Animales , Masculino , Neoplasias Hipofisarias/patología , Neoplasias Hipofisarias/veterinaria , Chinchilla , Hipófisis/patología , Adenoma/patología , Adenoma/veterinaria
19.
Sensors (Basel) ; 23(2)2023 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-36679755

RESUMEN

(1) Background and Goal: Several studies have investigated the association of sleep, diurnal patterns, and circadian rhythms with the presence and with the risk states of mental illnesses such as schizophrenia and bipolar disorder. The goal of our study was to examine actigraphic measures to identify features that can be extracted from them so that a machine learning model can detect premorbid latent liabilities for schizotypy and bipolarity. (2) Methods: Our team developed a small wrist-worn measurement device that collects and identifies actigraphic data based on an accelerometer. The sensors were used by carefully selected healthy participants who were divided into three groups: Control Group (C), Cyclothymia Factor Group (CFG), and Positive Schizotypy Factor Group (PSF). From the data they collected, our team performed data cleaning operations and then used the extracted metrics to generate the feature combinations deemed most effective, along with three machine learning algorithms for categorization. (3) Results: By conducting the training, we were able to identify a set of mildly correlated traits and their order of importance based on the Shapley value that had the greatest impact on the detection of bipolarity and schizotypy according to the logistic regression, Light Gradient Boost, and Random Forest algorithms. (4) Conclusions: These results were successfully compared to the results of other researchers; we had a similar differentiation in features used by others, and successfully developed new ones that might be a good complement for further research. In the future, identifying these traits may help us identify people at risk from mental disorders early in a cost-effective, automated way.


Asunto(s)
Trastorno Bipolar , Esquizofrenia , Humanos , Trastorno Bipolar/diagnóstico , Actigrafía/métodos , Esquizofrenia/diagnóstico , Sueño , Ritmo Circadiano
20.
Int J Mol Sci ; 24(4)2023 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-36835525

RESUMEN

Altered organokine expression contributes to increased cardiometabolic risk in obesity. Our aim was to evaluate the associations of serum afamin with glucose homeostasis, atherogenic dyslipidemia, and other adipokines in severe obesity to clarify the early metabolic alterations. 106 non-diabetic obese (NDO) subjects and 62 obese patients with type 2 diabetes matched for age, gender, and body mass index (BMI) were enrolled in this study. We compared their data with 49 healthy, lean controls. Serum afamin and retinol-binding protein 4 (RBP4), as well as plasma plasminogen activator inhibitor-1 (PAI-1), were measured with ELISA, and lipoprotein subfractions were analyzed using Lipoprint gel electrophoresis. Afamin and PAI-1 found to be significantly higher in the NDO and T2M group (p < 0.001 and p < 0.001, respectively) than in the controls. In contrast, RBP4 was unexpectedly lower in the NDO and T2DM group compared to controls (p < 0.001). Afamin showed negative correlations with mean LDL size and RBP4, but positive correlations with anthropometric, glucose/lipid parameters, and PAI-1 in both the overall patients and the in NDO + T2DM groups. BMI, glucose, intermediate HDL, and small HDL were predictors of afamin. Afamin may serve as a biomarker for the severity of cardiometabolic disturbances in obesity. The complexity of organokine patterns in NDO subjects draws attention to the diverse spectrum of obesity-related comorbidities.


Asunto(s)
Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Humanos , Inhibidor 1 de Activador Plasminogénico/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Obesidad/metabolismo , Índice de Masa Corporal , Glucosa , Proteínas Plasmáticas de Unión al Retinol
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