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Background: Human Papillomavirus (HPV) is the most common sexually transmitted infection. High-risk HPV types are the main cause of cervical cancer. Annually, cervical cancer is among the top 10 cancers in Puerto Rican women, with 22% of these cases ending in death. The purpose of this study was to establish the prevalence of high-risk HPV genotypes in a large cohort of young women living in Puerto Rico. Methods: A retrospective longitudinal analysis was performed with a sample of 5,749 HPV results obtained from a clinical database of women ages 21 to 29 from 2014-2016. Results: Outcomes indicate that among those with a positive HPV result, about one-third (35.2%) had a high-risk HPV infection. Women between the ages of 21 to 23 showed the highest prevalence (40.6%) of high-risk HPV. Among genotypes HPV 16 and 18, genotype 16 was the most prevalent. Interestingly, 85.4% of results were positive for other high-risk HPV types other than 16 or 18. Of the 458 women who had at least two tests completed, 217 had an initial positive result for HPV and only 108 (49.7%) resolved the infection. Conclusions: This study confirms the high prevalence of several genotypes of high-risk HPV in young women in a large Puerto Rican sample.

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RESUMEN El sotol (Dasylirion cedrosanum Trel.), especie endémica del noreste de México, presenta interés económico y social por su aprovechamiento comercial. El objetivo del presente trabajo fue caracterizar la germinación, crecimiento vegetativo y morfología floral de D. cedrosanum del matorral rosetófilo de Coahuila. Se sometieron 3 lotes de 100 semillas a un proceso de imbibición y se registró el porcentaje de germinación. La caracterización de la germinación se realizó a las plántulas cultivadas en laboratorio, mientras que la morfología vegetativa se determinó en plantas adultas tomadas de un jardín botánico, con fecha de siembra conocida y a las cuales no se les dio un manejo de cultivo. La descripción de la morfología floral se realizó en plantas silvestres del cañón de San Lorenzo, Saltillo, Coahuila, México. La primera fase de la imbibición duró 48 h e incrementó 52 % el peso; la segunda o de latencia duró 48 h alcanzando un 55 %; y la tercera concluyó a las 120 h con un incremento total del 60 % de peso. Las semillas emitieron el hipocótilo a partir del quinto día. En el décimo día se obtuvo 98 % de germinación. Entre las características morfológicas distintivas de la especie, las inflorescencias, conocidas como "escapos florales", registraron una altura promedio de 3.39 m. Las flores fueron actinomorfas y unisexuales. La flor estaminada presentó perianto sin diferenciación de tépalos y sépalos. Las flores pistiladas mostraron pedicelos y receptáculo corto. El polen fue elíptico, de abertura monosulcada, con dimensión de 15 μm x 30 μm. Los frutos fueron secos e indehiscentes, conocidos como samara. Las semillas fueron turbinadas de contorno trigonal. El análisis de las características de germinación y morfología vegetativa y floral del sotol permitieron comprender las adaptaciones que esta planta ha desarrollado para crecer en los ambientes semiáridos del país.

ABSTRACT Sotol (Dasylirion cedrosanum Trel.), endemic species of northeastern Mexico, has attracted economic and social interest due to its commercial potencial. The objective of this work was to characterize the germination, vegetative growth and floral morphology of D. cedrosanum from the rosetophyllous scrub of Coahuila. Three batches of 100 seeds were submitted to an imbibition process and the germination percentage was recorded. The characterization of the germination was carried out on the seedlings grown in the laboratory, while the vegetative morphology was determined in adult plants taken from a botanical garden, with a known planting date and which were not given a crop management. The description of the floral morphology was carried out on wild plants from the San Lorenzo canyon, near the municipality of Saltillo, Coahuila, Mexico. The imbibition showed the first phase of absorption within 48 h, with an increase of 52 % in weight. The third phase began at 96 h with an increase of 55 % in weight. The seeds emitted the hypocotyl from the fifth day. On the tenth day 98 % germination was obtained. Among the distinctive morphological characteristics of the species, the inflorescences, known as "floral scapes", recorded an average height of 3.39 m. The flowers were actinomorphic and unisexual. The staminate flower presented perianth without differentiation of tepals and sepals, while the pistillate flowers showed pedicels and a short receptacle. The pollen was elliptical, with a monosulcate opening, with a dimension of 15 μm x 30 μm. The fruits were dry and indehiscent, known as samara. The seeds were turbinated with a trigonal contour. The germination and characteristics of the sotol corresponded to adaptations that allow it to grow in the semi-arid environment of this region of the country.

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2-Ketones are signal molecules reported as plant growth stimulators, but their applications in vegetables have yet to be achieved. Solid lipid nanoparticles (SLNs) emerge as a relevant nanocarrier to develop formulations for the controlled release of 2-ketones. In this sense, seedlings of Lactuca sativa exposed to 125, 375, and 500 µL L-1 of encapsulated 2-nonanone and 2-tridecanone into SLNs were evaluated under controlled conditions. SLNs evidenced a spherical shape with a size of 230 nm. A controlled release of encapsulated doses of 2-nonanone and 2-tridecanone was observed, where a greater release was observed as the encapsulated dose of the compound increased. Root development was strongly stimulated mainly by 2-tridecanone and leaf area (25-32%) by 2-nonanone. Chlorophyll content increased by 15.8% with exposure to 500 µL L-1 of 2-nonanone, and carotenoid concentration was maintained with 2-nonanone. Antioxidant capacity decreased (13-62.7%) in L. sativa treated with 2-ketones, but the total phenol concentration strongly increased in seedlings exposed to some doses of 2-ketones. 2-Tridecanone strongly modulates the enzymatic activities associated with the scavenging of H2O2 at intra- and extracellular levels. In conclusion, 2-ketones released from SLNs modulated the growth and the antioxidant system of L. sativa, depending on the dose released.

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The excessive application of pesticides and fertilizers has generated losses in biological diversity, environmental pollution, and harmful effects on human health. Under this context, nanotechnology constitutes an innovative tool to alleviate these problems. Notably, applying nanocarriers as controlled release systems (CRSs) for agrochemicals can overcome the limitations of conventional products. A CRS for agrochemicals is an eco-friendly strategy for the ecosystem and human health. Nanopesticides based on synthetic and natural polymers, nanoemulsions, lipid nanoparticles, and nanofibers reduce phytopathogens and plant diseases. Nanoproducts designed with an environmentally responsive, controlled release offer great potential to create formulations that respond to specific environmental stimuli. The formulation of nanofertilizers is focused on enhancing the action of nutrients and growth stimulators, which show an improved nutrient release with site-specific action using nanohydroxyapatite, nanoclays, chitosan nanoparticles, mesoporous silica nanoparticles, and amorphous calcium phosphate. However, despite the noticeable results for nanopesticides and nanofertilizers, research still needs to be improved. Here, we review the relevant antecedents in this topic and discuss limitations and future challenges.

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The use of trace elements in agriculture as a complement to crop fertilization programs is a practice that is gaining importance and relevance worldwide. Iodine and selenium perform essential functions in human health, related to the proper functioning of the thyroid gland, acting as antioxidants and antiproliferatives, and their limited intake through food consumption can cause malnutrition, reflected in the abnormal development and growth of humans. This research aimed to evaluate the nutraceutical quality of tomato (Solanum lycopersicum L.) in response to seed priming based on KIO3 (0, 100, 150, 200, 250 mg L-1) and Na2SeO3 (0, 0.5, 1, 2, 3 mg L-1), performed by interaction from a 52-factorial design and by independent factors in a 24-h imbibition time. The tomato crop was established under greenhouse conditions in 10-L polyethylene containers containing peat moss and perlite 1:1 (v/v). Regarding non-enzymatic antioxidant compounds, lycopene, ß-carotene and flavonoid contents in tomato fruits significantly increased with KIO3 and Na2SeO3 treatments; however, vitamin C content was negatively affected. KIO3 increased the phenol and chlorophyll-a contents of leaves. In relation to enzymatic activity, KIO3 positively influenced GSH content and PAL activity in tomato fruits. KIO3 also positively influenced GSH content in leaves while negatively affecting PAL and APX activities. Na2SeO3 favored GSH content and GPX activity in tomato fruits and leaves. Na2SeO3 negatively affected the antioxidant capacity of hydrophilic compounds by ABTS in fruits and leaves and favored hydrophilic compounds by DPPH in leaves. Seed imbibition based on KIO3 and Na2SeO3 is a method that is implemented in the tomato crop and presents interesting aspects that favor the nutraceutical quality of tomato fruits, which may contribute to increasing the intake of these minerals in humans through tomato consumption.

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The tomato crop is susceptible to various types of stress, both biotic and abiotic, which affect the morphology, physiology, biochemistry, and genetic regulation of plants. Among the biotic factors, is the phytopathogen Fusarium oxysporum f. sp. lycopersici (Fol), which can cause losses of up to 100%. Graphene-Cu nanocomposites have emerged as a potential alternative for pathogen control, thanks to their antimicrobial activity and their ability to induce the activation of the antioxidant defense system in plants. In the present study, the effect of the Graphene-Cu nanocomposites and the functionalization of graphene in the tomato crop inoculated with Fol was evaluated, analyzing their impacts on the antioxidant defense system, the foliar water potential (Ψh), and the efficiency of photosystem II (PSII). The results demonstrated multiple positive effects; in particular, the Graphene-Cu nanocomposite managed to delay the incidence of the "vascular wilt" disease and reduce the severity by 29.0%. This translated into an increase in the content of photosynthetic pigments and an increase in fruit production compared with Fol. In addition, the antioxidant system of the plants was improved, increasing the content of glutathione, flavonoids, and anthocyanins, and the activity of the GPX, PAL, and CAT enzymes. Regarding the impact on the water potential and the efficiency of the PSII, the plants inoculated with Fol and treated with the Graphene-Cu nanocomposite responded better to biotic stress compared with Fol, reducing water potential by up to 31.7% and Fv/Fm levels by 32.0%.

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Blueberry is a highly demanded and consumed fruit due to its beneficial effects on human health, because of its bioactive compounds with a high antioxidant capacity. The interest in increasing the yield and quality of blueberries has led to the application of some innovative techniques such as biostimulation. The objective of this research was to assess the effect of the exogenous application of glutamic acid (GLU) and 6-benzylaminopurine (6-BAP) as biostimulants on flower bud sprouting, fruit quality, and antioxidant compounds in blueberry cv. Biloxi. The application of GLU and 6-BAP positively affected bud sprouting, fruit quality, and antioxidant content. The application of 500 and 10 mg L-1 GLU and 6-BAP, respectively, increased the number of flower buds, while 500 and 20 mg L-1 generated fruits with higher content of flavonoids, vitamin C, and anthocyanins and higher enzymatic activity of catalase and ascorbate peroxidase enzymes. Hence, the application of these biostimulants is an effective way to enhance the yield and fruit quality of blueberries.

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Nanoparticles are recognized due to their particular physical and chemical properties, which are conferred due to their size, in the range of nanometers. Nanoparticles are recognized for their application in medicine, electronics, and the textile industry, among others, but also in agriculture. The application of nanoparticles as nanofertilizers and biostimulants can help improve growth and crop productivity, and it has therefore been mentioned as an essential tool to control the adverse effects of abiotic stress. However, nanoparticles have also been noted for their exceptional antimicrobial properties. Therefore, this work reviews the state of the art of different nanoparticles that have shown the capacity to control biotic stress in plants. In this regard, metal and metal oxide nanoparticles, polymeric nanoparticles, and others, such as silica nanoparticles, have been described. Moreover, uptake and translocation are covered. Finally, future remarks about the studies on nanoparticles and their beneficial role in biotic stress management are made.

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Zn is an indispensable nutrient for crops that usually presents low bioavailability. Different techniques have been proposed to improve the bioavailability of Zn, including the use of nanofertilizers. The objective of the study was to evaluate the applications of drench (D) and foliar (F) ZnO nanoparticles (NZnO) compared to those of ionic Zn2+ (ZnSO4) in lettuce. The plants cv. Great Lakes 407 was produced in pots of 4 L with perlite-peat moss (1:1) under greenhouse conditions. The treatments consisted of NZnO applications that replaced the total Zn provided with a Steiner solution, as follows: Zn2+ (100%D) (control); Zn2+ (50%D+50%F); NZnO (100%D); NZnO (50%D+50%F); NZnO (75%D); NZnO (50%D); NZnO (75%F) and NZnO (50%F). Four applications of Zn were made with a frequency of 15 days. 75 days after transplant (DAP), the fresh and dry biomass, chlorophyll a, b, and ß-carotene, phenolics, flavonoids, antioxidant capacity, vitamin C, glutathione, H2O2, total protein, and enzymatic activity of PAL, CAT, APX, and GPX were evaluated. The mineral concentrations (N, P, K, Ca, Mg, S, Cu, Fe, Mn, Mo, Zn, Ni, and Si) in the leaves and roots of plants were also determined. The results showed that, compared to Zn2+, NZnO promoted increases in biomass (14-52%), chlorophylls (32-69%), and antioxidant compounds such as phenolics, flavonoids, and vitamin C. The activity of enzymes like CAT and APX, as well as the foliar concentration of Ca, Mg, S, Fe, Mn, Zn, and Si increased with NZnO. A better response was found in the plants for most variables with foliar applications of NZnO equivalent to 50-75% of the total Zn2+ applied conventionally. These results demonstrate that total replacement of Zn2+ with NZnO is possible, promoting fertilizer efficiency and the nutraceutical quality of lettuce.

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The objective of this review is to present a compilation of the application of various biostimulants in strawberry plants. Strawberry cultivation is of great importance worldwide, and, there is currently no review on this topic in the literature. Plant biostimulation consists of using or applying physical, chemical, or biological stimuli that trigger a response-called induction or elicitation-with a positive effect on crop growth, development, and quality. Biostimulation provides tolerance to biotic and abiotic stress, and more absorption and accumulation of nutrients, favoring the metabolism of the plants. The strawberry is a highly appreciated fruit for its high organoleptic and nutraceutical qualities since it is rich in phenolic compounds, vitamins, and minerals, in addition to being a product with high commercial value. This review aims to present an overview of the information on using different biostimulation techniques in strawberries. The information obtained from publications from 2000-2022 is organized according to the biostimulant's physical, chemical, or biological nature. The biochemical or physiological impact on plant productivity, yield, fruit quality, and postharvest life is described for each class of biostimulant. Information gaps are also pointed out, highlighting the topics in which more significant research effort is necessary.