Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
587
result(s) for
"Herrera, Raul"
Sort by:
Molecular Events Occurring During Softening of Strawberry Fruit
by
Herrera, Raul
,
Mattus-Araya, Elena
,
Moya-León, Maria Alejandra
in
Abscisic acid
,
Auxins
,
Carbohydrates
2019
Changes in fruit texture taking place during ripening, described as softening, are mainly due to alterations in structure and/or composition of the cell wall. Several non-covalent interactions between the three carbohydrate polymers of the cell wall, cellulose, pectins and hemicellulose, and many structural proteins and ions, enable a complex structure. During softening, the disassembly of the cell wall structure takes place, mediated by a complete set of cell wall degrading enzymes or proteins. Softening is a coordinated event that requires the orchestrated participation of a wide variety of proteins. Plant hormones and a set of transcription factors are the organizers of this multi-protein effort. Strawberry is a non climacteric fruit that softens intensively during the last stages of development. The Chilean strawberry fruit (
), the maternal relative of the commercial strawberry (
×
), softens even faster than commercial strawberry. Softening of the Chilean strawberry fruit has been studied at different levels: changes in cell wall polymers, activity of cell wall degrading enzymes and transcriptional changes of their genes, providing a general view of the complex process. The search for the 'orchestra director' that could coordinate softening events in strawberry fruit has been focussed on hormones like ABA and auxins, and more precisely the relation ABA/AUX. These hormones regulate the expression of many cell wall degrading enzyme genes, and this massive transcriptional change that takes place involves the participation of key transcriptional factors (TF). This review provides an update of the present knowledge regarding the softening of strawberry fruit. Nevertheless, the entire softening process is still under active research especially for the great influence of texture on fruit quality and its high impact on fruit shelf life, and therefore it is expected that new and promising information will illuminate the field in the near future.
Journal Article
review of wood thermal pretreatments to improve wood composite properties
by
Pelaez-Samaniego, Manuel Raul
,
Espinoza-Herrera, Raul
,
Yadama, Vikram
in
absorption
,
Biomedical and Life Sciences
,
Cellulose
2013
The objective of this paper is to review the published literature on improving properties of wood composites through thermal pretreatment of wood. Thermal pretreatment has been conducted in moist environments using hot water or steam at temperatures up to 180 and 230 °C, respectively, or in dry environments using inert gases at temperatures up to 240 °C. In these conditions, hemicelluloses are removed, crystallinity index of cellulose is increased, and cellulose degree of polymerization is reduced, while lignin is not considerably affected. Thermally modified wood has been used to manufacture wood–plastic composites, particleboard, oriented strand board, binderless panels, fiberboard, waferboard, and flakeboard. Thermal pretreatment considerably reduced water absorption and thickness swelling of wood composites, which has been attributed mainly to the removal of hemicelluloses. Mechanical properties have been increased or sometimes reduced, depending on the product and the conditions of the pretreatment. Thermal pretreatment has also shown to improve the resistance of composites to decay.
Journal Article
Follow-up patterns after positive primary aldosteronism screening
2025
Primary aldosteronism (PA) screening remains underdiagnosed at <2% of eligible patients, with inconsistent interpretation of positive screening results across institutions. This study investigated whether patients with positive PA case screening test results received appropriate follow-up interventions. We assessed plasma renin activity (PRA) and aldosterone concentration (PAC), calculating the aldosterone-to-renin ratio (ARR). Three commonly used criteria defined positive case detection: PAC ≥ 10 ng/dL and PRA < 1 ng/mL/h; ARR ≥ 20 and PAC ≥ 10 ng/dL; and ARR ≥ 30 and PAC ≥ 10 ng/dL. We identified 237 patients meeting at least one criterion between April 2018 and May 2023, then assessed follow-up care at least 6 months post-screening. Adequate follow-up included documented abnormal results in progress notes, further PA diagnostics, new MRA treatment, or specialist referral. Inadequate follow-up was observed across all screening criteria: 37% (82/222) of patients meeting PAC ≥ 10 ng/dL and PRA < 1 ng/mL/h, 38% (89/237) of those meeting ARR ≥ 20 and PAC ≥ 10 ng/dL, and 30% (53/180) of those meeting ARR ≥ 30 and PAC ≥ 10 ng/dL lacked appropriate care. History of hypokalemia (p < 0.001), English as primary language (p ≤ 0.007), and higher socioeconomic status (p ≤ 0.06) were consistently associated with adequate follow-up. These findings highlight the need for standardized criteria and automated alerts to improve follow-up after positive PA screening.
Journal Article
The behavior of adult Drosophila in the wild
2018
Little is known about how Drosophila adults behave in the wild, including mating, allocation of food and space, and escape from predators. This lack of information has negative implications for our ability to understand the capabilities of the nervous system to integrate sensory cues necessary for the adaptation of organisms in natural conditions. We characterized a set of behavioral routines of D. melanogaster and D. simulans adults in three ecologically different orchards: grape, apple and prickly pear. We also investigated how the flies identify conspecifics and aliens in the wild to better understand relationships between group formation and adaptation of Drosophila to breeding sites. We characterized the locations by recording in each orchard humidity, temperature, illumination conditions, pH of fruits, the presence/absence of other Drosophila species and the predator ant Linepithema humile. Our findings suggest that the home range of these species of Drosophila includes decaying fruits and, principally, a variety of microhabitats that surround the fruits. The ecological heterogeneity of the orchards and odors emitted by adult D. melanogaster and D. simulans influence perch preferences, cluster formation, court and mating, egg-laying site selection, and use of space. This is one of the first large examinations of the association between changing, complex environments and a set of adult behaviors of Drosophila. Therefore, our results have implications for understanding the genetic differentiation and evolution of populations of species in the genus Drosophila.
Journal Article
Interaction and integration among behaviors of adult Drosophila in nature
2023
Living in environments whose ecologies vary in periods as short as 24 h is a challenge for animals as Drosophila species that inhabit pear and apple orchards. These orchards have sunny and shady sections. The size and shape of these habitats change daily according to the position of the sun in the sky. Sunny areas are related to dryness and water loss, and shady places have lower temperatures and higher humidity. The presence of heterospecific flies may lead to competition for space and food. In sunny habitats we did not find adult Drosophila . In shady sections we found conspecific groups D . melanogaster , D . simulans , D . immigrans , D . subobscura , and the Chilean endemic D . pavani perched on grasses and herbs at 8–10 cm from fruits that had fallen on the ground. In the fruits, 99% of the adults were females and they were not grouped. The way in which daily changes in the size and shape of shady habitats together with the presence of heterospecific adults influence the selection of places to live is poorly understood in Drosophila . Our experiments show that adults of the five species prefer dark areas. The experimental results show that the odors of each species: i) influence conspecifics to select similar perch sites and decrease mobility, and ii) increase mobility in heterospecific adults and modify their perch site preferences. Attractions between conspecifics, the repulsions between species, and preferences for shaded areas matter in choosing a place to live in the five Drosophila species. These behaviors seem to have evolved as coordinated routines, contributing to the coexistence of the five Drosophila species in the apple and pear orchards examined.
Journal Article
Anticancer Effect of Pomegranate Peel Polyphenols against Cervical Cancer
by
Flores-Gallegos, Adriana Carolina
,
Rodríguez-Herrera, Raul
,
Teniente, Sandra Lucía
in
Acids
,
anticancer
,
antineoplastic activity
2023
Polyphenols are a broad group of bioactive phytochemicals with powerful antioxidant, anti-inflammatory, immunomodulatory, and antiviral activities. Numerous studies have demonstrated that polyphenol extracts obtained from natural sources can be used for the prevention and treatment of cancer. Pomegranate peel extract is an excellent source of polyphenols, such as punicalagin, punicalin, ellagic acid, and caffeic acid, among others. These phenolic compounds have antineoplastic activity in in vitro models of cervical cancer through the regulation of cellular redox balance, induction of apoptosis, cell cycle arrest, and modulation of different signaling pathways. The current review summarizes recent data from scientific reports that address the anticancer activity of the predominant polyphenol compounds present in PPE and their different mechanisms of action in cervical cancer models.
Journal Article
Binding of Plasmodium merozoite proteins RON2 and AMA1 triggers commitment to invasion
2011
The commitment of Plasmodium merozoites to invade red blood cells (RBCs) is marked by the formation of a junction between the merozoite and the RBC and the coordinated induction of the parasitophorous vacuole. Despite its importance, the molecular events underlying the parasite's commitment to invasion are not well understood. Here we show that the interaction of two parasite proteins, RON2 and AMA1, known to be critical for invasion, is essential to trigger junction formation. Using antibodies (Abs) that bind near the hydrophobic pocket of AMA1 and AMA1 mutated in the pocket, we identified RON2's binding site on AMA1. Abs specific for the AMA1 pocket blocked junction formation and the induction of the parasitophorous vacuole. We also identified the critical residues in the RON2 peptide (previously shown to bind AMA1) that are required for binding to the AMA1 pocket, namely, two conserved, disulfide-linked cysteines. The RON2 peptide blocked junction formation but, unlike the AMA1-specific Ab, did not block formation of the parasitophorous vacuole, indicating that formation of the junction and parasitophorous vacuole are molecularly distinct steps in the invasion process. Collectively, these results identify the binding of RON2 to the hydrophobic pocket of AMA1 as the step that commits Plasmodium merozoites to RBC invasion and point to RON2 as a potential vaccine candidate.
Journal Article
Impact of quarantine due to COVID-19 pandemic on health and lifestyle conditions in older adults from Centro American countries
by
Cárdenas-Valverde, Juan-Carlos
,
Mendoza-Ruvalcaba, Neyda Ma
,
Ramos-Henderson, Miguel
in
Activities of Daily Living
,
Adults
,
Aged
2022
The impact of quarantine in older adults have been reported in several studies with contradictory results, reporting from negative effects to no significant outcomes or even beneficial consequences. Heterogeneity in aging plays a role in each region, the aim of this study is to analyze the impact of quarantine on health conditions (physical and mental) and lifestyle in older adults in five Centro American countries during COVID-19 pandemic.
In this cross-sectional study, n = 712 older adults 60 years and older from Mexico, Guatemala, El Salvador, Honduras and Costa Rica were assessed by telephone. Sociodemographic data, physical and mental health, lifestyle and quarantine conditions were asked previous informed consent.
In general, mean of days in quarantine at the moment of the study was 142 days (approximately four months and three weeks). In the analysis of the impact of the days in quarantine effects were found on the frequency of falls, functional ability in Activities of Daily Living (ADL), general cognitive function, memory, orientation, language, frequency of drinking alcohol, having a balanced diet, and being active cognitively. Some differences were found between countries.
Effects of quarantine on older adults in Centro America, requires attention of governments and healthcare to prevent long term morbidity and disability, and to promote healthy aging.
Journal Article
Extending the range of Plasmodium falciparum transmission blocking antibodies
by
Narum, David L.
,
Duffy, Patrick E.
,
Canepa, Gaspar
in
Allergy and Immunology
,
Antibodies
,
Antibodies, Blocking
2023
Recent work demonstrating that asymptomatic carriers of P. falciparum parasites make up a large part of the infectious reservoir highlights the need for an effective malaria vaccine. Given the historical challenges of vaccine development, multiple parasite stages have been targeted, including the sexual stages required for transmission. Using flow cytometry to efficiently screen for P. falciparum gamete/zygote surface reactivity, we identified 82 antibodies that bound live P. falciparum gametes/zygotes. Ten antibodies had significant transmission-reducing activity (TRA) in a standard membrane feeding assay and were subcloned along with 9 nonTRA antibodies as comparators. After subcloning, only eight of the monoclonals obtained have significant TRA. These eight TRA mAbs do not recognize epitopes present in any of the current recombinant transmission-blocking vaccine candidates, Pfs230D1M, Pfs48/45.6C, Pf47 D2 and rPfs25. One TRA mAb immunoprecipitates two surface antigens, Pfs47 and Pfs230, that are expressed by both gametocytes and gametes/zygotes. These two proteins have not previously been reported to associate and the recognition of both by a single TRA mAb suggests the Pfs47/Pfs230 complex is a new vaccine target. In total, Pfs230 was the dominant target antigen, with five of the eight TRA mAbs and 8 of 11 nonTRA gamete/zygote surface reactive mAbs interacting with Pfs230. Of the three remaining TRA mAbs, two recognized non-reduced, parasite-produced Pfs25 and one bound non-reduced, parasite-produced Pfs48/45. None of the TRA mAbs bound protein on an immunoblot of reduced gamete/zygote extract and two TRA mAbs were immunoblot negative, indicating none of the new TRA epitopes are linear. The identification of eight new TRA mAbs that bind epitopes not included in any of the constructs currently under advancement as transmission-blocking vaccine candidates may provide new targets worthy of further study.
Journal Article
Mucilage extracted from Chilean papaya seeds is enriched with homogalacturonan domains
by
Zúñiga, Sebastian
,
Herrera, Raúl
,
Salazar-Carrasco, Alejandra
in
Acids
,
Biochemical composition
,
Carica pubescens
2024
Chilean papaya, also known as mountain papaya ( Vasconcellea pubescens ), is a fruit valued for its nutritional value and pleasant fragrance. The oblong fruit, featuring five ridges and a seed-filled mucilage cavity, is typically consumed cooked due to its high protease content. The mucilage and the seeds are usually discarded as byproducts. This study analyzed the biochemical composition of mountain papaya seed mucilage using methods such as HPAEC and immunolabeling. Results revealed that papaya seeds yield nearly 20% of their weight in mucilage polysaccharides, which can be separated into soluble and adherent layers. The mucilage exhibited a high proportion of acidic sugars, indicating that homogalacturonan (HG) is the predominant domain. It also contained other domains like rhamnogalacturonan-I (RG-I) and hemicelluloses, predominantly xyloglucan. The HG-rich mucilage, currently considered waste, emerges as a promising source of polysaccharides, indicating its multifaceted utility in various industrial applications.
Journal Article