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1.
Dev Biol ; 442(2): 288-300, 2018 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-30120927

RESUMEN

Metazoan eggs have a specialized coat of extracellular matrix that aids in sperm-egg recognition. The coat is rapidly remodeled after fertilization to prevent polyspermy and establish a more permanent barrier to protect the developing embryo. In nematodes, this coat is called the vitelline layer, which is remodeled into the outermost layer of a rigid and impermeable eggshell. We have identified three key components of the vitelline layer structural scaffold - PERM-2, PERM-4 and CBD-1, the first such proteins to be described in the nematode C. elegans. CBD-1 tethered PERM-2 and PERM-4 to the nascent vitelline layer via two N-terminal chitin-binding domains. After fertilization, all three proteins redistributed from the zygote surface to the outer eggshell. Depletion of PERM-2 and PERM-4 from the scaffold led to a porous vitelline layer that permitted soluble factors to leak through the eggshell and resulted in embryonic death. In addition to its role in vitelline layer assembly, CBD-1 is also known to anchor a protein complex required for fertilization and egg activation (EGG-1-5/CHS-1/MBK-2). We found the PERM complex and EGG complex to be functionally independent, and structurally organized through distinct domains of CBD-1. CBD-1 is thus a multifaceted regulator that promotes distinct aspects of vitelline layer assembly and egg activation. In sum, our findings characterize the first vitelline layer components in nematodes, and provide a foundation through which to explore both conserved and species-specific strategies used by animals to build protective barriers following fertilization.


Asunto(s)
Proteínas de Caenorhabditis elegans/metabolismo , Proteínas Portadoras/metabolismo , Cáscara de Huevo/metabolismo , Membrana Vitelina/metabolismo , Animales , Caenorhabditis elegans , Fertilización , Glicoproteínas de Membrana/metabolismo , Oogénesis , Óvulo/metabolismo , Cigoto/metabolismo
2.
J Tradit Complement Med ; 14(2): 182-190, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38481545

RESUMEN

Background: Gomphrena perennis L. is a native plant of South America whose pharmacological properties have not been studied yet. Aim: To evaluate the cardiovascular and intestinal pharmacological effects of Gomphrena perennis L. leaves tincture (GphT) and the mechanisms involved. Experimental procedure: The chromatographic profile of GphT was done. Its ex vivo effects were evaluated by contractile concentration-response curves (CRCs) obtained from the agonist carbachol or calcium found in isolated rat small intestine, as well as in the relaxant CRCs. Cardiac effects were evaluated on isolated rat hearts exposed to ischemia/reperfusion (I/R). Experiments in vivo were performed to evaluate the diuretic activity in conscious rats and the hypotensive effect in anaesthetised rats. Results: Fifteen flavonoids were identified in GphT by HPLC-UV, including diosmin. GphT induced a non-competitive inhibition in both carbachol and calcium CRCs on rat small intestine. The first was not affected by indomethacin. Moreover, GphT, unlike diosmin, relaxed the contracture produced by a high-potassium solution in a dose-dependently way. Neither propranolol nor l-NAME changed it. GphT did not show diuretic activity but induced hypotension insensitive to l-NAME. While GphT perfusion of isolated hearts increased injury consequent to I/R, oral administration was cardioprotective and reversed by l-NAME. However, diosmin did not improve the post-ischemic recovery. Conclusions: This study supports the use of Gomphrena perennis L. tincture as an antispasmodic and hypotensive agent. Moreover, it has been demonstrated to be preventive of post-ischemic cardiac dysfunction. However, diosmin would not be responsible for these effects.

3.
Front Res Metr Anal ; 7: 944333, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36277735

RESUMEN

The challenges and consequences of climate change have brought together governments around the world to advance scientific knowledge and programmatic actions to develop mitigation strategies while promoting sustainable development. The United States and China-the countries with the highest science expenditures globally-have historically developed a range of joint international research collaborations. However, under the "America First" agenda put forth by the Trump Administration, bilateral diplomatic relations with China reached their highest confrontational peak. Under this scenario science diplomacy served as a catalyst to maintain scientific collaborations between both countries. In 2018, the US National Science Foundation and the China National Natural Science Foundation launched the InFEWS US-China program to promote collaborations to expand food, energy, and water nexus (FEW Nexus) research and applications. Over the past four years, 20 research projects have been awarded from the US side and 47 publications have been reported as research output. By carrying out a descriptive analysis of the InFEWS US-China research and scholarly outputs, we find evidence of the crucial role played by the Chinese scientific diaspora who led 65% of the projects awarded. We find that there is a generally good understanding of the interdependencies between FEW systems included in the project abstracts. However, in the InFEWS US-China scholarly outputs generated to date, there is a lack of usage of a clear FEW Nexus theoretical framework. Further research should address intentional policies that enhance the involvement of scientific diasporas in their home countries to better address climate, sustainability, and development challenges.

4.
Arch Argent Pediatr ; 120(5): e210-e212, 2022 10.
Artículo en Español | MEDLINE | ID: mdl-36190222

RESUMEN

Ewing's sarcoma is a malignant neoplasm mainly occurring in the bone, with other locations being exceptional. In the case of primary intracranial presentations, it is essential to rule out metastatic lesions as well as other neuroectodermal tumors that may require different diagnostic and therapeutic approaches. We present a 14-year-old patient who consulted for upper eyelid ptosis of left eye associated with a 2-month history of diplopia, with imaging evidence of extra-axial tumor lesion, located at the level of the interpeduncular cistern. Complete excision was performed, with a pathological diagnosis of Ewing's sarcoma of midbrain location.


El sarcoma de Ewing es una neoplasia de origen más frecuentemente óseo; otras localizaciones son excepcionales. En el caso de las presentaciones primarias intracraneales, resulta imprescindible descartar que se trate de un secundarismo así como también de otros tumores neuroectodérmicos que puedan requerir distintos abordajes diagnósticos y terapéuticos. Se presenta a una paciente de 14 años que consultó por ptosis palpebral de ojo izquierdo asociado a diplopía de 2 meses de evolución; los estudios por imágenes mostraron una lesión tumoral extraaxial situada a nivel de la cisterna interpeduncular. Se realizó la exéresis completa, con diagnóstico anatomopatológico de sarcoma de Ewing de ubicación mesencefálica.


Asunto(s)
Neoplasias Óseas , Sarcoma de Ewing , Adolescente , Neoplasias Óseas/patología , Neoplasias Óseas/terapia , Humanos , Mesencéfalo/patología , Sarcoma de Ewing/diagnóstico , Sarcoma de Ewing/cirugía
5.
J Tradit Complement Med ; 12(2): 141-151, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35528474

RESUMEN

Schinus lentiscifolius (Anacardiaceae) is widely used in folk medicine for treating gastrointestinal and emotional complaints but there are no scientific studies that support these uses. This work aims at evaluating the antispasmodic and central effects of S. lentiscifolius as well as the flavonoids presence in the tincture (SchT) and the composition of the essential oil (SchO). SchT inhibited the concentration-response curves (CRC) of carbachol and calcium in a non-competitive way in isolated rat intestine, bladder and uterus. SchT also non-competitively inhibited the CRC of histamine in guinea-pig intestine and the CRCs of serotonin and oxytocin in rat uterus. Isoquercetin and rutin were identified in SchT. The behavioral effects of SchT, SchO and infusion of S. lentiscifolius leaves (SchW) were tested in mice. These extracts showed an anxiolytic-like effect in the novelty-suppressed feeding test, which was reversed by flumazenil except in SchO-treated mice. Only SchO reduced the spontaneous locomotor function in the open field test. Also, SchT and SchW decreased immobility time in both, the tail suspension (TST) and forced swimming tests, while SchO produced the same effect in the TST. d-limonene and α-santalol were the main components found in SchO. The results demonstrated that extracts obtained from S. lentiscifolius leaves were effective as intestinal, urinary and uterine antispasmodics. SchT and SchW exhibited anxiolytic and antidepressant properties without sedation, whereas SchO showed also sedative properties. Therefore, the present study gives preclinical support to the traditional use of this plant for gastrointestinal and depressive or emotional symptoms.

6.
Arch. argent. pediatr ; 120(5): e210-e212, oct. 2022. ilus
Artículo en Español | LILACS, BINACIS | ID: biblio-1395751

RESUMEN

El sarcoma de Ewing es una neoplasia de origen más frecuentemente óseo; otras localizaciones son excepcionales. En el caso de las presentaciones primarias intracraneales, resulta imprescindible descartar que se trate de un secundarismo así como también de otros tumores neuroectodérmicos que puedan requerir distintos abordajes diagnósticos y terapéuticos. Se presenta a una paciente de 14 años que consultó por ptosis palpebral de ojo izquierdo asociado a diplopía de 2 meses de evolución; los estudios por imágenes mostraron una lesión tumoral extraaxial situada a nivel de la cisterna interpeduncular. Se realizó la exéresis completa, con diagnóstico anatomopatológico de sarcoma de Ewing de ubicación mesencefálica


Ewing's sarcoma is a malignant neoplasm mainly occurring in the bone, with other locations being exceptional. In the case of primary intracranial presentations, it is essential to rule out metastatic lesions as well as other neuroectodermal tumors that may require different diagnostic and therapeutic approaches. We present a 14-year-old patient who consulted for upper eyelid ptosis of left eye associated with a 2-month history of diplopia, with imaging evidence of extra-axial tumor lesion, located at the level of the interpeduncular cistern. Complete excision was performed, with a pathological diagnosis of Ewing's sarcoma of midbrain location.


Asunto(s)
Humanos , Femenino , Adolescente , Sarcoma de Ewing/cirugía , Sarcoma de Ewing/diagnóstico , Neoplasias Óseas/patología , Neoplasias Óseas/terapia , Mesencéfalo/patología
7.
J Cataract Refract Surg ; 36(9): 1508-16, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20692563

RESUMEN

PURPOSE: To assess the visual outcomes after cataract surgery with implantation of a refractive multifocal intraocular lens (IOL) with a +3.00 D addition (add). SETTING: Centro Internacional de Microcirugia Ocular, Seville, Spain. METHODS: This prospective study evaluated visual outcomes after cataract surgery with implantation of a Rayner M-flex 630F +3 IOL over a 12-month follow-up. Monocular and binocular uncorrected and corrected distance, intermediate, and near visual acuities were recorded. Distance contrast sensitivity under photopic and mesopic conditions, subjective dysphotopic phenomena, and subjective spectacle dependence were assessed. RESULTS: The study enrolled 32 eyes of 22 patients. Twelve months postoperatively, the mean monocular corrected distance acuity was 0.03 +/- 0.05 logMAR and the mean corrected near acuity was 0.04 +/- 0.05 logMAR. The binocular uncorrected and corrected near acuity was 0.25 +/- 0.08 logMAR and 0.03 +/- 0.02 logMAR, respectively, at 6 months, with no changes thereafter. No patients reported dysphotopic phenomena at the 12-month visit. Of patients having binocular IOL implantation, 90% were spectacle independent for distance vision and 70% for near vision at 6 months. CONCLUSION: The refractive multifocal IOL with a +3.00 D add provided satisfactory visual outcomes through a full range of vision.


Asunto(s)
Implantación de Lentes Intraoculares , Lentes Intraoculares , Facoemulsificación , Seudofaquia/fisiopatología , Agudeza Visual/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Sensibilidad de Contraste/fisiología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Óptica y Fotónica , Estudios Prospectivos , Resultado del Tratamiento , Visión Binocular/fisiología
8.
Rev. argent. radiol ; 83(2): 65-67, jun. 2019. ilus
Artículo en Español | LILACS | ID: biblio-1020467
9.
J Enzyme Inhib Med Chem ; 22(3): 253-65, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17674806

RESUMEN

A similarity-based algorithm based on a previously developed model is applied in the classification of two sets of anticonvulsant and non-anticonvulsant drugs. Each set is composed of a) anticonvulsant compounds that have shown moderate to high activity in the Maximal Electroshock Seizure (MES) test and b) drugs with other biological activities or poor activity in the MES test. The results from the analysis of variance (ANOVA) indicate that the proposed algorithm is able to differentiate anticonvulsant from non-anticonvulsant drugs. The proposed model may then be useful in the identification of new anticonvulsant agents through virtual screening of large virtual libraries of chemical structures.


Asunto(s)
Algoritmos , Anticonvulsivantes/química , Anticonvulsivantes/clasificación , Química Farmacéutica/estadística & datos numéricos , Análisis de Varianza , Animales , Anticonvulsivantes/farmacología , Evaluación Preclínica de Medicamentos/estadística & datos numéricos , Electrochoque , Bibliotecas Digitales , Ratones , Modelos Químicos , Relación Estructura-Actividad Cuantitativa , Convulsiones/tratamiento farmacológico , Convulsiones/etiología
10.
Mol Divers ; 10(3): 361-75, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17031538

RESUMEN

We have performed virtual screening to identify new lead trypanothione reductase inhibitor (TRI) compounds, enzyme present in Tripanozoma cruzi, the agent responsible of Chagas disease. From a training set of 58 compounds, linear discriminant analysis (LDA) was performed using 2D and 3D descriptors as discriminating variables in order to find out which function of descriptors characterizes the active TRI. The values of the statistical parameters F--Snedecor and Wilk's lambda for the discriminant function (DF) showed good statistical significance, as long as the rate of success in the prediction for both the training and the test set: 91.38% and 88.63%, in that order. Internal validation through the Leave--Group--Out methodology was performed with good results, assuring the stability of the DF. Afterwards, the DF was applied in virtual screening of 422,367 compounds. The optimum range of values of octanol--water partition coefficient for a compound to develop trypanothione reductase inhibition was applied as a second filtering criteria. 739 structurally heterogeneous drugs of the virtual library were selected as promissory TRI.


Asunto(s)
Simulación por Computador , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , NADH NADPH Oxidorreductasas/antagonistas & inhibidores , Tripanocidas/farmacología , Animales , Análisis Discriminante , Modelos Biológicos , Modelos Químicos , Modelos Moleculares , Estructura Molecular , Relación Estructura-Actividad Cuantitativa , Tripanocidas/química , Trypanosoma cruzi/enzimología
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