1,204 research outputs found

    Quince (Cydonia oblonga) in vitro plant root formation through an automated temporary inmersion system, and its acclimation

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    Artículo científicoQuince (Cydonia oblonga) is a non-traditional fruit tree found in Costa Rica that has therapeutic and nutritional properties; however its slow growth and root formation prevents the production of a homogeneous population when using conventional farming techniques. Hence, the aim of this research project was to generate uniform plant material in a reduced time span using a temporary immersion bioreactor system (RITAS ®). A semisolid rooting MS culture medium supplemented with 0.1 mg L-1 NAA; 0.3 mg L-1 IBA and 3% sucrose (pH 6.5), developed in the Centro de Investigación en Biotecnología (CIB), Instituto Tecnológico de Costa Rica (ITCR), in Cartago, was used as a reference medium. Four different variations in the sucrose concentration (1%, 2%, 3%, and 4%) were performed in liquid medium. Each trial was evaluated with in vitro plants which had been previously exposed to the culture medium of the corresponding treatments, in a stationary mode and for a 15 day long period, and with in vitro plants without any previous treatment (a total of eight treatments). The comparison of the root formation percentages evidenced the clear effect of sucrose concentration used, with the best results obtained when using the 2% sucrose trial with no pre-treatment (73.3%). The in vitro plants were acclimated in cylinders made out of peat, have previously been disinfected with fungicide, and placed in a humidity chamber at a 20.5°C average temperature and a 75,5% relative humidity for the establishment of weekly fertilizing cycles. The acclimation process generated an 80% survival rate, since several seedlings experienced stem strangulation caused by a fungal attack. The conidiophores identified through optical and scanning electron microscopy evidenced the presence of Cladosporium spp., which was controlled with carbendazim and iprodione fungicides

    Summary of Pb isotopic compositions in epitermal precios metal deposits, Orcopampa área of Southern Peru, Berenguela area of Western Bolivia, and the Maricunga belt in north-central Chile

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    The Mesozoic and Cenozoic Central Andes are divided into three Pb isotopic provinces, based upon the Pb isotopic compositions of ore minerals (MacFarlane et al., 1990). Macfarlane et al., 0990), furthermore, argue that the Pb isotopic compositions of the ore minerals reílect those of the igneous rocks associated with the deposits. Province I lies along the coast of Perú, Chile, and westernmost Bolivia. Mcsozoic and early Cenozoic volcapic and plutonic ares built upon a rifted and thinned continental margin dominate this province. Three subprovinces are distinguished based upon slight differences in Pb isotopic compositions. Province la includes northern and central Chile south of 19°S; province lb includes central Perú north of 13°S; whereas province le includes central and southern Perú between the two other subprovinces. Province II lies in the high Andes of central Perú and, perhaps, in northern Chile and Argentina, where miogeoclinal sedimentary rocks crop out and the crust underwent a lower magnitude of extension in the early Mesozoic. This region generally represents a back-arc position relative to the Mesozoic and early Cenozoic magmatic ares, and extensive magmatism related to the Andean cycle has only occurred since the Oligocene. Paleozoic ares are the dominant basement in this province. Province III lies in the Cordillera Oriental and Altiplano of Perú and Bolivia where Paleozoic, Mesozoic, and Cenozoic sedimentary rocks are multiply dcformed by thrust faults. Magma ti-e episodes of Triassic to Jurassic and Oligocene to Miocene age are documented. Proterozoic rocks of the Brazilian shicld are underthrust beneath the Cordillera Oriental, with the youngest shortcning episode beginning in the Oligocene. Province III is subdivided into two subprovinces: ma lies in southeastern Perú where both episodes of magmatism occurred, whereas IIIb lies in Bolivia where magmatism is primarily of Oligocene and Miocene age. Pb isotopic compositions for Province I are slightly less radiogenic than those from province II, whereas province III isotopic compositions are much more varied with consistently higher 207Pb/ 204pb and 208pb/204pb at a given 206pb/ 204pb_Province I Pb isotopic compositions (206pb/ 204pb =18.21-18.82; 207Pb/2<YíPb = 15.55-15.69; 2º8Pb/2º4Pb = 38.11-38.95) overlap with and extend below the average crustal growth curve of Staccy and Kramers (1975) on the uranogenic diagram (207pb/204pb versus 206pb/204Pb). Province lT Pb isotopic compositions (206pb/2<Yípb = 18.76-18.90; 207pb/204pb 15.62-15.73; 208pb/204pb 38.63-39.16) and Province III Pb isotopic compositions (206pb/204Pb 17.97-25.18; 207pb/204pb 15.51-16.00; 208pb/20/4pb 37.71-40.07) lie above the average crustal growth curve on the same diagram. The Pb isotopic compositions from these last two provinces require contribution from a high mu (238U/204pb) Proterozoic or Archean source. On the thorogcnic Pb isotopic variation diagram (208Pb/ 204Pb versus 206pb/204pb), isotopic compositions for province I, 11, and IIIa scatter along the average crustal growth curve of Stacey and Kramers (1975-) indicating that a time averaged Th/U ratio - 4 (the average cristal value) characterizes the Central Andes. Pb isotopic compositions for province IIIb are the most radiogenic and also the most heterogeneous. The variable radiogenic Pb isotopic compositions of province III suggcst heterogeneous upper cristal sources, whereas the isotopic compositions of province I probably reflect a mafic cristal lithospheric source, probably modified by subduction processcs. Province II isotopic compositions conceivably represent a mix betwecn the two model reservoirs

    Tifus murino en el cairo-valle ¿brote o condición endémica emergente?

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    En el Municipio de El Cairo Valle se reportó un brote de Tifus Murino, el cual habitualmente no se diagnostica en la región. Se presenta una serie de casos obtenidos del Sistema de Vigilancia Epidemiológica del Municipio de El Cairo, administrado por el Hospital Municipal

    Telomerase activity, estrogen receptors (α, β), Bcl-2 expression in human breast cancer and treatment response

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    BACKGROUND: The mechanism for maintaining telomere integrity is controlled by telomerase, a ribonucleoprotein enzyme that specifically restores telomere sequences, lost during replication by means of an intrinsic RNA component as a template for polymerization. Among the telomerase subunits, hTERT (human telomerase reverse transcriptase) is expressed concomitantly with the activation of telomerase. The role of estrogens and their receptors in the transcriptional regulation of hTERT has been demonstrated. The current study determines the possible association between telomerase activity, the expression of both molecular forms of estrogen receptor (ERα and ERβ) and the protein bcl-2, and their relative associations with clinical parameters. METHODS: Tissue samples from 44 patients with breast cancer were used to assess telomerase activity using the TRAP method and the expression of ERα, ERβ and bcl-2 by means of immunocytochemical techniques. RESULTS: Telomerase activity was detected in 59% of the 44 breast tumors examined. Telomerase activity ranged from 0 to 49.93 units of total product generated (TPG). A correlation was found between telomerase activity and differentiation grade (p = 0.03). The only significant independent marker of response to treatment was clinical stage. We found differences between the frequency of expression of ERα (88%) and ERβ (36%) (p = 0.007); bcl-2 was expressed in 79.5% of invasive breast carcinomas. We also found a significant correlation between low levels of telomerase activity and a lack of ERβ expression (p = 0.03). CONCLUSION: Lower telomerase activity was found among tumors that did not express estrogen receptor beta. This is the first published study demonstrating that the absence of expression of ERβ is associated with low levels of telomerase activity

    Study protocol for the multicentre cohorts of Zika virus infection in pregnant women, infants, and acute clinical cases in Latin America and the Caribbean: The ZIKAlliance consortium

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    Background: The European Commission (EC) Horizon 2020 (H2020)-funded ZIKAlliance Consortium designed a multicentre study including pregnant women (PW), children (CH) and natural history (NH) cohorts. Clinical sites were selected over a wide geographic range within Latin America and the Caribbean, taking into account the dynamic course of the ZIKV epidemic. Methods: Recruitment to the PW cohort will take place in antenatal care clinics. PW will be enrolled regardless of symptoms and followed over the course of pregnancy, approximately every 4 weeks. PW will be revisited at delivery (or after miscarriage/abortion) to assess birth outcomes, including microcephaly and other congenital abnormalities according to the evolving definition of congenital Zika syndrome (CZS). After birth, children will be followed for 2 years in the CH cohort. Follow-up visits are scheduled at ages 1-3, 4-6, 12, and 24 months to assess neurocognitive and developmental milestones. In addition, a NH cohort for the characterization of symptomatic rash/fever illness was designed, including follow-up to capture persisting health problems. Blood, urine, and other biological materials will be collected, and tested for ZIKV and other relevant arboviral diseases (dengue, chikungunya, yellow fever) using RT-PCR or serological methods. A virtual, decentralized biobank will be created. Reciprocal clinical monitoring has been established between partner sites. Substudies of ZIKV seroprevalence, transmissio

    CIBERER : Spanish national network for research on rare diseases: A highly productive collaborative initiative

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    Altres ajuts: Instituto de Salud Carlos III (ISCIII); Ministerio de Ciencia e Innovación.CIBER (Center for Biomedical Network Research; Centro de Investigación Biomédica En Red) is a public national consortium created in 2006 under the umbrella of the Spanish National Institute of Health Carlos III (ISCIII). This innovative research structure comprises 11 different specific areas dedicated to the main public health priorities in the National Health System. CIBERER, the thematic area of CIBER focused on rare diseases (RDs) currently consists of 75 research groups belonging to universities, research centers, and hospitals of the entire country. CIBERER's mission is to be a center prioritizing and favoring collaboration and cooperation between biomedical and clinical research groups, with special emphasis on the aspects of genetic, molecular, biochemical, and cellular research of RDs. This research is the basis for providing new tools for the diagnosis and therapy of low-prevalence diseases, in line with the International Rare Diseases Research Consortium (IRDiRC) objectives, thus favoring translational research between the scientific environment of the laboratory and the clinical setting of health centers. In this article, we intend to review CIBERER's 15-year journey and summarize the main results obtained in terms of internationalization, scientific production, contributions toward the discovery of new therapies and novel genes associated to diseases, cooperation with patients' associations and many other topics related to RD research

    Effects of alirocumab on types of myocardial infarction: insights from the ODYSSEY OUTCOMES trial

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    Aims  The third Universal Definition of Myocardial Infarction (MI) Task Force classified MIs into five types: Type 1, spontaneous; Type 2, related to oxygen supply/demand imbalance; Type 3, fatal without ascertainment of cardiac biomarkers; Type 4, related to percutaneous coronary intervention; and Type 5, related to coronary artery bypass surgery. Low-density lipoprotein cholesterol (LDL-C) reduction with statins and proprotein convertase subtilisin–kexin Type 9 (PCSK9) inhibitors reduces risk of MI, but less is known about effects on types of MI. ODYSSEY OUTCOMES compared the PCSK9 inhibitor alirocumab with placebo in 18 924 patients with recent acute coronary syndrome (ACS) and elevated LDL-C (≥1.8 mmol/L) despite intensive statin therapy. In a pre-specified analysis, we assessed the effects of alirocumab on types of MI. Methods and results  Median follow-up was 2.8 years. Myocardial infarction types were prospectively adjudicated and classified. Of 1860 total MIs, 1223 (65.8%) were adjudicated as Type 1, 386 (20.8%) as Type 2, and 244 (13.1%) as Type 4. Few events were Type 3 (n = 2) or Type 5 (n = 5). Alirocumab reduced first MIs [hazard ratio (HR) 0.85, 95% confidence interval (CI) 0.77–0.95; P = 0.003], with reductions in both Type 1 (HR 0.87, 95% CI 0.77–0.99; P = 0.032) and Type 2 (0.77, 0.61–0.97; P = 0.025), but not Type 4 MI. Conclusion  After ACS, alirocumab added to intensive statin therapy favourably impacted on Type 1 and 2 MIs. The data indicate for the first time that a lipid-lowering therapy can attenuate the risk of Type 2 MI. Low-density lipoprotein cholesterol reduction below levels achievable with statins is an effective preventive strategy for both MI types.For complete list of authors see http://dx.doi.org/10.1093/eurheartj/ehz299</p
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