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1.
bioRxiv ; 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39149256

RESUMEN

Centrosomes rely upon proteins within the pericentriolar material to nucleate and organize microtubules. Several mRNAs also reside at centrosomes, although less is known about how and why they accumulate there. We previously showed that local Centrocortin (Cen) mRNA supports centrosome separation, microtubule organization, and viability in Drosophila embryos. Here, using Cen mRNA as a model, we examine mechanisms of centrosomal mRNA localization. We find that while the Cen N'-terminus is sufficient for protein enrichment at centrosomes, multiple domains cooperate to concentrate Cen mRNA at this location. We further identify an N'-terminal motif within Cen that is conserved among dynein cargo adaptor proteins and test its contribution to RNA localization. Our results support a model whereby Cen protein enables the accumulation of its own mRNA to centrosomes through a mechanism requiring active translation, microtubules, and the dynein motor complex. Taken together, our data uncover the basis of translation-dependent localization of a centrosomal RNA required for mitotic integrity.

2.
Genetics ; 226(4)2024 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-38290049

RESUMEN

Mutations in SETD2 are among the most prevalent drivers of renal cell carcinoma (RCC). We identified a novel single nucleotide polymorphism (SNP) in SETD2, E902Q, within a subset of RCC patients, which manifests as both an inherited or tumor-associated somatic mutation. To determine if the SNP is biologically functional, we used CRISPR-based genome editing to generate the orthologous mutation within the Drosophila melanogaster Set2 gene. In Drosophila, the homologous amino acid substitution, E741Q, reduces H3K36me3 levels comparable to Set2 knockdown, and this loss is rescued by reintroduction of a wild-type Set2 transgene. We similarly uncovered significant defects in spindle morphogenesis, consistent with the established role of SETD2 in methylating α-Tubulin during mitosis to regulate microtubule dynamics and maintain genome stability. These data indicate the Set2 E741Q SNP affects both histone methylation and spindle integrity. Moreover, this work further suggests the SETD2 E902Q SNP may hold clinical relevance.


Asunto(s)
Carcinoma de Células Renales , Proteínas de Drosophila , Neoplasias Renales , Animales , Humanos , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/patología , Histonas/genética , Histonas/metabolismo , Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Polimorfismo de Nucleótido Simple , Neoplasias Renales/genética , Neoplasias Renales/metabolismo , Neoplasias Renales/patología , Huso Acromático/genética , Huso Acromático/metabolismo , N-Metiltransferasa de Histona-Lisina/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo
3.
Int J Clin Pract ; 75(12): e14936, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34605116

RESUMEN

AIM OF THE STUDY: The aim of the study was to investigate whether antenatal corticosteroid therapy (ACST) could impact neurological condition, as assessed through muscular tone, of prematurely born infants. METHODS: All 82 patients at risk of preterm delivery treated and delivered over 12 months were divided into two equal groups regarding the use of ACST. The investigated parameters were pregnancy complications, biophysical profile, Apgar score, gestational age of delivery and all postpartum complications. Neurological development and muscular tone were evaluated at the 1st, 3rd, 6th and 12th months of life using Vojta's method, which classifies muscular tone as good, hypotonic or hypertonic. RESULTS: After therapy, infants from the treated and control groups differed in biophysical profile, Apgar score, length of intensive care, occurrence of respiratory distress syndrome and intraventricular haemorrhage. During the follow-up, significantly more infants from the ACST group had good muscular tone when compared with those from the control group. Regression analysis showed that ASCT can significantly impact an infant's muscular tone. Still, the week of delivery and the complications such as diabetes mellitus, intrauterine growth restriction and respiratory distress syndrome, could change the association of ACST and infants' muscular tone. CONCLUSION: ACST was associated with the positive neurological outcomes of prematurely born infants when assessed through their muscular tone.


Asunto(s)
Complicaciones del Embarazo , Nacimiento Prematuro , Síndrome de Dificultad Respiratoria del Recién Nacido , Corticoesteroides , Femenino , Edad Gestacional , Humanos , Lactante , Recién Nacido , Embarazo , Nacimiento Prematuro/prevención & control , Síndrome de Dificultad Respiratoria del Recién Nacido/tratamiento farmacológico , Síndrome de Dificultad Respiratoria del Recién Nacido/prevención & control
4.
Development ; 148(3)2021 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-33462111

RESUMEN

Formation of a zygote is coupled with extensive epigenetic reprogramming to enable appropriate inheritance of histone methylation and prevent developmental delays. In Caenorhabditis elegans, this reprogramming is mediated by the H3K4me2 demethylase SPR-5 and the H3K9 methyltransferase, MET-2. In contrast, the H3K36 methyltransferase MES-4 maintains H3K36me2/3 at germline genes between generations to facilitate re-establishment of the germline. To determine whether the MES-4 germline inheritance pathway antagonizes spr-5; met-2 reprogramming, we examined the interaction between these two pathways. We found that the developmental delay of spr-5; met-2 mutant progeny is associated with ectopic H3K36me3 and the ectopic expression of MES-4-targeted germline genes in somatic tissues. Furthermore, the developmental delay is dependent upon MES-4 and the H3K4 methyltransferase, SET-2. We propose that MES-4 prevents crucial germline genes from being repressed by antagonizing maternal spr-5; met-2 reprogramming. Thus, the balance of inherited histone modifications is necessary to distinguish germline versus soma and prevent developmental delay.This article has an associated 'The people behind the papers' interview.


Asunto(s)
Caenorhabditis elegans/metabolismo , Carisoprodol/metabolismo , Células Germinativas/metabolismo , Histonas/metabolismo , Animales , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Epigénesis Genética , Epigenómica , Expresión Génica , Técnicas de Silenciamiento del Gen , Metilación , Procesamiento Proteico-Postraduccional
5.
Sensors (Basel) ; 19(4)2019 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-30781694

RESUMEN

In the paper the description of an experiment for a comparative analysis of two different methods for deformation determination, geodetic and 2D deflection sensors based on fiber-optic curvature sensors (FOCSs) is given. The experiment is performed by a using specially designed assembly which makes it possible to apply both methods. For performing geodetic measurements, a geodetic micro-network is established. Measurements by applying a 2D deflection sensor and three total stations are carried out for comparison. The data processing comprises graphical and numerical analysis of the results. Based on the presented results the potential of 2D deflection sensor application in structural health monitoring (SHM) procedures is indicated. The analysis of the measurement results also indicates the importance of integrating various types of sensors for obtaining more accurate and more reliable deformation measurements results.

6.
Ginekol Pol ; 89(5): 240-248, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30084475

RESUMEN

OBJECTIVES: Treatment of endometriosis prior to IVF/ICSI could be followed by the significant reduction of ovarian reserve. The aim is to identify potential markers of the IVF/ICSI outcome in patients with endometriosis associated infertility and to evaluate their clinical significance. MATERIAL AND METHODS: The prospective cohort study included 73 patients with primary infertility caused by endometriosis that were subjected to 77 IVF/ICSI cycles. Patients were classified into two groups. In the first group some type of treatment had previously been applied, and in the second group patients were immediately subjected to the IVF/ICSI procedures. RESULTS: When pregnancy was achieved, there were significantly more patients under 35 years of age, more patients with primary infertility duration up to 3 years, and more patients with endometriosis that was previously treated (77.4%) (p < 0.039). In the cases of the successful outcome Endometriosis Fertility Index > 7, lower basal FSH and FSH/LH ratio were found, as well as significantly higher basal E2, basal P4 and AMH. Significantly lower doses of gonadotropins were needed in cases of the successful outcome, and long protocol with agonists was more frequently used. Multivariate logistic regres-sion analysis showed that previous therapy of endometriosis, P4 ≥ 0.7 ng/mL, AMH ≥ 0.9 ng/mL, A class of embryos, and the use of long protocol with agonists were predictors of the successful IVF/ICSI outcome. CONCLUSIONS: Therapy for endometriosis, AMH and P4 levels appeared to be predictors for the successful IVF/ICSI outcome and the use of long protocol with agonists could be advised in these cycles.


Asunto(s)
Endometriosis/complicaciones , Endometriosis/terapia , Fertilización In Vitro/estadística & datos numéricos , Infertilidad Femenina/terapia , Inyecciones de Esperma Intracitoplasmáticas/estadística & datos numéricos , Adulto , Estudios de Cohortes , Femenino , Fármacos para la Fertilidad Femenina/uso terapéutico , Humanos , Infertilidad Femenina/etiología , Embarazo , Índice de Embarazo , Pronóstico , Estudios Prospectivos , Resultado del Tratamiento
7.
Appl Opt ; 53(30): 6999-7003, 2014 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-25402786

RESUMEN

By experimental measurement and from a numerical solution to the time-dependent power flow equation, the frequency response, bandwidth, mode coupling, and mode-dependent attenuation are determined for a low-numerical-aperture (NA) plastic optical fiber. Frequency response and bandwidth are specified as a function of fiber length. Numerical results are verified against experimental measurements. Mode coupling and modal attenuation are found to differ substantially between two fiber varieties of the same type (both low-NA, step-index, and plastic), implying their preferential suitability that is application-specific.

8.
Gynecol Endocrinol ; 29(6): 619-21, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23514220

RESUMEN

We report a case with bilateral tubal ampullary pregnancy after Clomifen Citrate medication. The first conception in the right tube was after intrauterine insemination or intercourse performed before insemination, while the second one was achieved 10 d after insemination, during the intercourse, in the left tube. This life-threatening and routinely unexpected finding must always have in mind all doctors dealing with patients in emergency care, especially those receiving fertility enhancing drugs. According to the literature data available, this is the first and unique such case in the literature.


Asunto(s)
Clomifeno/efectos adversos , Inseminación Artificial/efectos adversos , Embarazo Tubario/etiología , Embarazo Gemelar , Adulto , Clomifeno/uso terapéutico , Coito/fisiología , Trompas Uterinas/efectos de los fármacos , Trompas Uterinas/patología , Femenino , Fármacos para la Fertilidad Femenina/efectos adversos , Fármacos para la Fertilidad Femenina/uso terapéutico , Humanos , Embarazo , Embarazo Tubario/inducido químicamente , Embarazo Tubario/diagnóstico por imagen , Ultrasonografía
9.
Appl Opt ; 51(19): 4333-42, 2012 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-22772105

RESUMEN

A novel high-speed and high-sensitivity displacement measurement sensing system, based on the phase-locked low-coherence interferometry, is presented. The sensing system is realized by comprising the Michelson fiber-optic interferometer. In order to obtain quadrature signals at the interferometer outputs, a 3×3 fused silica fiber-optic directional coupler is used. Therefore, the usage of the interferometer phase modulation as well as the usage of the lock-in amplification has been avoided. In this way, the speed of such a realized sensing system is significantly increased in comparison with the standard phase-locked interferometric systems that can be found elsewhere in the literature. The bandwidth of the realized sensing system is limited by the first resonance frequency of the used piezo actuator to 4.6 kHz. The estimated noise floor in the displacement measurement is approximately 180 pm/√Hz.

10.
Naunyn Schmiedebergs Arch Pharmacol ; 385(1): 27-38, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21947254

RESUMEN

The in vivo role of endothelial nitric oxide synthase (eNOS) uncoupling mediating oxidative stress in ischemia/reperfusion (I/R) injury has not been well established. In vitro, eNOS coupling refers to the reduction of molecular oxygen to L-arginine oxidation and generation of L-citrulline and nitric oxide NO synthesis in the presence of an essential cofactor, tetrahydrobiopterin (BH(4)). Whereas uncoupled eNOS refers to that the electron transfer becomes uncoupled to L-arginine oxidation and superoxide is generated when the dihydrobiopterin (BH(2)) to BH(4) ratio is increased. Superoxide is subsequently converted to hydrogen peroxide (H(2)O(2)). We tested the hypothesis that promoting eNOS coupling or attenuating uncoupling after I/R would decrease H(2)O(2)/increase NO release in blood and restore postreperfused cardiac function. We combined BH(4) or BH(2) with eNOS activity enhancer, protein kinase C epsilon (PKC ε) activator, or eNOS activity reducer, PKC ε inhibitor, in isolated rat hearts (ex vivo) and femoral arteries/veins (in vivo) subjected to I(20 min)/R(45 min). When given during reperfusion, PKC ε activator combined with BH(4), not BH(2), significantly restored postreperfused cardiac function and decreased leukocyte infiltration (p < 0.01) while increasing NO (p < 0.05) and reducing H(2)O(2) (p < 0.01) release in femoral I/R veins. These results provide indirect evidence suggesting that PKC ε activator combined with BH(4) enhances coupled eNOS activity, whereas it enhanced uncoupled eNOS activity when combined with BH(2). By contrast, the cardioprotective and anti-oxidative effects of the PKC ε inhibitor were unaffected by BH(4) or BH(2) suggesting that inhibition of eNOS uncoupling during reperfusion following sustained ischemia may be an important mechanism.


Asunto(s)
Biopterinas/análogos & derivados , Daño por Reperfusión Miocárdica/fisiopatología , Óxido Nítrico Sintasa de Tipo III/fisiología , Proteína Quinasa C-epsilon/fisiología , Animales , Biopterinas/farmacología , Vena Femoral/efectos de los fármacos , Vena Femoral/metabolismo , Corazón/efectos de los fármacos , Corazón/fisiopatología , Peróxido de Hidrógeno/metabolismo , Técnicas In Vitro , Masculino , Contracción Miocárdica/efectos de los fármacos , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/patología , Miocardio/patología , NG-Nitroarginina Metil Éster/farmacología , Neutrófilos/fisiología , Óxido Nítrico/metabolismo , Estrés Oxidativo/efectos de los fármacos , Proteína Quinasa C-epsilon/antagonistas & inhibidores , Ratas , Ratas Sprague-Dawley
11.
Adv Pharmacol Sci ; 2010: 963914, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21188246

RESUMEN

Reduced nitric oxide (NO) bioavailability and increased oxidative stress are major factors mediating ischemia/reperfusion (I/R) injury. Tetrahydrobiopterin (BH(4)) is an essential cofactor of endothelial NO synthase (eNOS) to produce NO, whereas dihydrobiopterin (BH(2)) can shift the eNOS product profile from NO to superoxide, which is further converted to hydrogen peroxide (H(2)O(2)) and cause I/R injury. The effects of BH(4) and BH(2) on oxidative stress and postreperfused cardiac functions were examined in ex vivo myocardial and in vivo femoral I (20 min)/R (45 min) models. In femoral I/R, BH(4) increased NO and decreased H(2)O(2) releases relative to saline control, and these effects correlated with improved postreperfused cardiac function. By contrast, BH(2) decreased NO release relative to the saline control, but increased H(2)O(2) release similar to the saline control, and these effects correlated with compromised postreperfused cardiac function. In conclusion, these results suggest that promoting eNOS coupling to produce NO and decrease H(2)O(2) may be a key mechanism to restore postreperfused organ function during early reperfusion.

12.
J Environ Manage ; 91(12): 2404-23, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20705383

RESUMEN

Empirical critical loads for N deposition effects and maps showing areas projected to be in exceedance of the critical load (CL) are given for seven major vegetation types in California. Thirty-five percent of the land area for these vegetation types (99,639 km(2)) is estimated to be in excess of the N CL. Low CL values (3-8 kg N ha(-1) yr(-1)) were determined for mixed conifer forests, chaparral and oak woodlands due to highly N-sensitive biota (lichens) and N-poor or low biomass vegetation in the case of coastal sage scrub (CSS), annual grassland, and desert scrub vegetation. At these N deposition critical loads the latter three ecosystem types are at risk of major vegetation type change because N enrichment favors invasion by exotic annual grasses. Fifty-four and forty-four percent of the area for CSS and grasslands are in exceedance of the CL for invasive grasses, while 53 and 41% of the chaparral and oak woodland areas are in exceedance of the CL for impacts on epiphytic lichen communities. Approximately 30% of the desert (based on invasive grasses and increased fire risk) and mixed conifer forest (based on lichen community changes) areas are in exceedance of the CL. These ecosystems are generally located further from emissions sources than many grasslands or CSS areas. By comparison, only 3-15% of the forested and chaparral land areas are estimated to be in exceedance of the NO(3)(-) leaching CL. The CL for incipient N saturation in mixed conifer forest catchments was 17 kg N ha(-1) yr(-1). In 10% of the CL exceedance areas for all seven vegetation types combined, the CL is exceeded by at least 10 kg N ha(-1) yr(-1), and in 27% of the exceedance areas the CL is exceeded by at least 5 kg N ha(-1) yr(-1). Management strategies for mitigating the effects of excess N are based on reducing N emissions and reducing site N capital through approaches such as biomass removal and prescribed fire or control of invasive grasses by mowing, selective herbicides, weeding or domestic animal grazing. Ultimately, decreases in N deposition are needed for long-term ecosystem protection and sustainability, and this is the only strategy that will protect epiphytic lichen communities.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Ciclo del Nitrógeno , Nitrógeno/análisis , California , Cambio Climático , Clima Desértico , Poaceae , Quercus , Tracheophyta , Incertidumbre
13.
Environ Pollut ; 155(3): 492-511, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18499320

RESUMEN

Empirical critical loads (CL) for N deposition were determined from changes in epiphytic lichen communities, elevated NO(3)(-) leaching in streamwater, and reduced fine root biomass in ponderosa pine (Pinus ponderosa Dougl. ex Laws.) at sites with varying N deposition. The CL for lichen community impacts of 3.1 kg ha(-1) year(-1) is expected to protect all components of the forest ecosystem from the adverse effects of N deposition. Much of the western Sierra Nevada is above the lichen-based CL, showing significant changes in lichen indicator groups. The empirical N deposition threshold and that simulated by the DayCent model for enhanced NO(3)(-)leaching were 17 kg N ha(-1) year(-1). DayCent estimated that elevated NO(3)(-) leaching in the San Bernardino Mountains began in the late 1950s. Critical values for litter C:N (34.1), ponderosa pine foliar N (1.1%), and N concentrations (1.0%) in the lichen Letharia vulpina ((L.) Hue) are indicative of CL exceedance.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Monitoreo del Ambiente/métodos , Agricultura Forestal , Nitrógeno/toxicidad , Tracheophyta , Contaminantes Atmosféricos/análisis , Biomasa , California , Ecosistema , Líquenes/crecimiento & desarrollo , Nitrógeno/análisis , Raíces de Plantas/crecimiento & desarrollo
14.
Naunyn Schmiedebergs Arch Pharmacol ; 378(1): 1-15, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18496674

RESUMEN

The role of protein kinase C epsilon (PKC epsilon) in polymorphonuclear leukocyte (PMN)-induced myocardial ischemia/reperfusion (MI/R) injury and novel-related mechanisms, such as regulation of vascular endothelium nitric oxide (NO) and hydrogen peroxide (H2O2) release from blood vessels, have not been previously evaluated. A cell-permeable PKC epsilon peptide activator (1-10 microM) significantly increased endothelial NO release from non-ischemic rat aortic segments (p < 0.01). By contrast, PKC epsilon peptide inhibitor (1-10 microM) dose-dependently decreased NO release (p < 0.01). Then, these corresponding doses of PKC epsilon activator or inhibitor were examined in MI/R. The PKC epsilon inhibitor (5 microM given during reperfusion, n=6) significantly attenuated PMN-induced postreperfused cardiac contractile dysfunction and PMN adherence/infiltration (both p < 0.01), and expression of intracellular adhesion molecule-1 (ICAM-1; p < 0.05). By contrast, only PKC epsilon activator pretreated hearts (5 muM PKC epsilon activator given before ischemia (PT), n = 6), not PKC epsilon activator given during reperfusion (5 microM, n=6) exerted significant cardioprotection (p < 0.01). Moreover, the NO synthase inhibitor, N(G)-nitro-L: -arginine methyl ester, did not block the cardioprotection of PKC epsilon inhibitor, whereas it completely abolished the cardioprotective effects of PKC epsilon activator PT. In addition, PKC epsilon inhibitor (0.4 mg/kg) significantly decreased H(2)O(2) release during reperfusion in a femoral I/R model (p < 0.01). Therefore, the cardioprotection of PKC epsilon inhibitor maybe related to attenuating ICAM-1 expression and H2O2 release during reperfusion. By contrast, the cardioprotective effects of PKC epsilon activator PT may be mediated by enhancing vascular endothelial NO release before ischemia.


Asunto(s)
Cardiotónicos/farmacología , Oligopéptidos/farmacología , Proteína Quinasa C-epsilon/efectos de los fármacos , Daño por Reperfusión/tratamiento farmacológico , Animales , Aorta/efectos de los fármacos , Aorta/metabolismo , Cardiotónicos/administración & dosificación , Relación Dosis-Respuesta a Droga , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Peróxido de Hidrógeno/metabolismo , Molécula 1 de Adhesión Intercelular/efectos de los fármacos , Molécula 1 de Adhesión Intercelular/metabolismo , Masculino , Óxido Nítrico/metabolismo , Oligopéptidos/administración & dosificación , Proteína Quinasa C-epsilon/metabolismo , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/fisiopatología
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