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The potential of starch-chitosan blends with poloxamer for the preparation of microparticles by spray-drying

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Particuology 2024年第6期89卷 1-10页

作者： Juan Enrique Barranco-García Carolina Caicedo Enrique Javier Jiménez-Regalado Carlos Espinoza-González graciela Morales Rocio Yaneli Aguirre-Loredo Abril Fonseca-García Tecnológico nacional de México/Instituto Tecnológico de Oaxaca Departamento de Química y BioquímicaAvenida Ing.Víctor Bravo Ahuja No.125Esquina Calzada Tecnológico68030OaxacaMexico Faculty of Engineering Unidad Central del Valle del Cauca(UCEVA)Carrera 17a 48-144763022TuluáColombia Centro de Investigación en Química Aplicada(CIQA) Blvd.Enrique Reyna Hermosillo 14025294SaltilloCoahuilaMexico Investigadoras por México COnAHCYT-CIQA Av.Insurgentes Sur 1562Col.Crédito Constructor03940Alcaldía Benito JuárezCDMXMexico

Using biopolymers as wall materials in spray drying poses challenges,particularly in attaining flowability and thermal stability among their physicochemical properties.This paper addresses these challenges by preparing microparticles using a blend of starch–chitosan and a poloxamer,commercially named Pluronic®F127.We aimed to elucidate the effects of varying poloxamer concentrations on the resulting particles through the spray drying technique.Blends with a poloxamer concentration of 3%(w/v)demonstrated a notably higher yield,especially when compared to those with 0%and 1%concentrations.Microparticles with 3%and 5%(w/v)poloxamer displayed a narrower particle size distribution,with the 3%blend showing a superior yield attributed to arrangements of blend components that improve flowability.X-ray diffraction analysis showcased the characteristic peaks of A-type starch form,with shifts suggesting enhanced interactions between components.Microparticles with increased poloxamer content showed elevated thermal degradation temperatures,with the 3%blend registering a significant rise,opening avenues for encapsulating heat-sensitive bioactive.This study primarily focuses on the preparation and basic characterization of microparticles.It underscores the potential of blends with optimal poloxamer concentrations in microencapsulation,emphasizing further research to harness their capabilities thoroughly.

关键词： Biopolymer Starch Chitosan Pluronic®F127 Microparticles Spray drying

Endophytic Occupation in nodules of Rhynchosia Plants from Semiarid Regions of Argentina

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Phyton-International Journal of Experimental Botany 2024年第6期93卷 1081-1099页

作者： Cinthia T.Lucero María de losÁ.Ruíz Fabiola Pagliero Carolina Castaño Mariela L.Ambrosino graciela S.Lorda Facultad de Ciencias Exactas y naturales Universidad Nacional de La PampaRuta Nacional 35km 330Santa RosaLa PampaCP6300Argentina InTA EEA Anguil“Ing.Agr.Guillermo Covas”Ruta nacional 5 km 580AnguilLa PampaCC116326Argentina

Beneﬁcial microbes can improve soil health by promoting soil structure,nutrient cycling,and disease suppression.In addition,a wide array of rhizospheric microbes are responsible for producing metabolically active compounds including various types of plant growth regulators.So,microbial biodiversity studies could contribute to the improvement of agricultural practices in deprived areas,such as the Pampean semiarid region.The vast majority of studies conducted on endophytic microorganisms have focused on intensive crop legume species.In contrast,little attention has been paid to microorganisms of native legumes,whose ecology is not directly affected by human action.In this study,endophytic microorganisms isolated from root nodules of a selected native legume of the genus Rhynchosia were characterized.Viable isolates were studied with a focus on their plant growth-pro-moting rhizobacteria(PGPR)properties.Considering the edaphic characteristics of the Pampean semiarid region,the isolates obtained were evaluated for their ability to grow under three salt stress conditions(50,100,and 200 mM naCl)and four different pH values(6,7,8,and 9).Based on their PGPR activities,the selected strains were phylogenetically grouped using BOX-PCR.The results showed great variability among the isolates in terms of the characteristics studied.native legumes manifested a wide endophytic variability and remarkable perfor-mance in PGPR activities.We conclude that they could be used as potential bioinoculants for legume cultivation,an excellent alternative to the use of chemical fertilizers that currently pollute the environment.

关键词： native strains endophytes PGPR native legumes stress

Meningoencephalitis due to Listeria monocytogenes in a Young Immunocompetent Patient: Case Report with Literature Review

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Advances in Infectious Diseases 2024年第1期14卷 213-219页

作者： Janette Alejandra Gamiño Gutierrez Gustavo Adolfo Hernández Valdez Arleth Anahí Montaño Gómez Jorge Morales Rojas graciela Gaddy Robles Martinez Anahi Herrera Ruelas Alin Kaori Ferreyra Gudiño Jocelin Celeste Jurado Cardona Jimena Jexabeth Ibáñez núñez Anahí Fierros Ramos Departmento de neurocirugia Hospital Civil de Guadalajara Fray Antonio Alcalde Guadalajara México Departamento de Medicina Interna ISSSTE Tepic General Hospital APP Tepic México

Meningoencephalitis secondary to Listeria monocytogenes (L. monocytogenes) mainly affects newborns, the elderly and immunocompromised people;there are extremely rare cases in which said infection occurs in immunocompetent individuals. We present the case of a young adult patient without immunocompromise, who developed meningoencephalitis due to L. monocytogenes;This case is exceptional, since it occurred in an individual outside the classic age group, in addition to not having risk factors, which is why it should be considered an atypical causal agent.

关键词： Meningitis Encephalitis Rhombencephalitis Listeria monocytogenes Immunocompetent

Involvement of Met receptor pathway in aggressive behavior of colorectal cancer cells induced by parathyroid hormone-related peptide

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World Journal of Gastroenterology 2022年第26期28卷 3177-3200页

作者： María Belén novoa Díaz Pedro Carriere graciela Gigola Ariel Osvaldo Zwenger natalia Calvo Claudia Gentili Departamento de Biología Bioquímica y FarmaciaUniversidad Nacional del Sur(UNS)-INBIOSUR(CONICET-UNS)Bahía Blanca 8000Buenos AiresArgentina Centro de Estudios Clínicos SAGA CEC SAGASantiago de Chile 8320000Chile

BACKGROUnD Parathyroid hormone-related peptide(PTHrP)plays a key role in the development and progression of many tumors.We found that in colorectal cancer(CRC)HCT116 cells,the binding of PTHrP to its receptor PTHR type 1(PTHR1)activates events associated with an aggressive phenotype.In HCT116 cell xenografts,PTHrP modulates the expression of molecular markers linked to tumor progression.Empirical evidence suggests that the Met receptor is involved in the development and evolution of CRC.Based on these data,we hypothesized that the signaling pathway trigged by PTHrP could be involved in the transactivation of Met and consequently in the aggressive behavior of CRC cells.AIM To elucidate the relationship among PTHR1,PTHrP,and Met in CRC models.METHODS For in vitro assays,HCT116 and Caco-2 cells derived from human CRC were incubated in the absence or presence of PTHrP(1-34)(10-8 M).Where indicated,cells were pre-incubated with specific kinase inhibitors or dimethylsulfoxide,the vehicle of the inhibitors.The protein levels were evaluated by Western blot technique.Real-time polymerase chain reaction(RT-qPCR)was carried out to determine the changes in gene expression.Wound healing assay and morpho logical monitoring were performed to evaluate cell migration and changes related to the epithelialmesenchymal transition(EMT),respectively.The number of viable HCT116 cells was counted by trypan blue dye exclusion test to evaluate the effects of irinotecan(CPT-11),oxaliplatin(OXA),or doxorubicin(DOXO)with or without PTHrP.For in vivo tests,HCT116 cell xenografts on 6-wk-old male n:nIH(S)_nu mice received daily intratumoral injections of PTHrP(40μg/kg)in 100μL phosphate-buffered saline(PBS)or the vehicle(PBS)as a control during 20 d.Humanitarian slaughter was carried out and the tumors were removed,weighed,and fixed in a 4%formaldehyde solution for subsequent treatment by immunoassays.To evaluate the expression of molecular markers in human tumor samples,we studied 23 specimens obtained from CRC patients which were treated at t

关键词： PTHrP MET receptor tyrosine kinase Parathyroid hormone receptor type 1 Colorectal cancer Drug resistance

Portal Venous Thrombosis and Splenic Hemangioma, Secondary to Acute Pancreatitis: Case Report

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Open Journal of Gastroenterology 2024年第1期14卷 11-17页

作者： Gustavo Adolfo Hernández Valdez Harvey Yair Zamora Veliz Estefany Gilberty Mendoza Verdin Quitzia Mayanim Rentería Fonseca Itzel Velázquez Viniegra Janette Alejandra Gamiño Gutierrez Diana Rita Velázquez Jimenez Florencio Favian Andrade Luis Fernando Baez Bustos Jorge Morales Rojas María Jacqueline Martínez Tejeda graciela Gaddy Robles Martínez Juan Antonio Contreras Escamilla Departamento de Medicina Interna ISSSTE Tepic General Hospital APP Tepic Nayarit México General Surgery Department ISSSTE Tepic General Hospital APP Tepic Nayarit México Hospital Civil Fray Antonio Alcalde Guadalajara Jalisco México

We present an unusual case of portal vein thrombosis with a splanchnic hemangioma secondary to acute biliary pancreatitis. We report a 45-year-old patient, who has systemic arterial hypertension in treatment, was admitted for abdominal pain in the epigastrium, with irradiation to the right hypochondrium, accompanied by nausea and vomiting of 10 occasions of bile content, physical examination with pain in the right hypochondrium, Murphy positive. We have laboratory studies with a lipase of 788, so a diagnosis of pancreatitis is made with an etiology to be determined. The laboratories suggestive of acute biliary pancreatitis (lipase 788.71);an imaging study was subsequently performed (ultrasonography) with the result of stone in the common bile duct. A laparoscopy was performed with relative improvement, so he was discharged and returned 20 days after surgery due to abdominal pain of the same intensity in the left hypochondrium. Ending his hospitalization with a splenectomy for splenic hemangioma with portal vein thrombosis.

关键词： Pancreatitis Esplenic Hemangioma Esplenectomy Portal Vein Thrombosis Surgery

Endophytes versus biotrophic and necrotrophic pathogens—are fungal lifestyles evolutionarily stable traits?

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Fungal Diversity 2013年第3期60卷 125-135页

作者： Luis Delaye graciela García-Guzmán Martin Heil Departamento de Ingeniería Genética Centro de Investigación y de Estudios Avanzados(CINVESTAV)IrapuatoGuanajuatoMexico Departamento de Ecología Evolutiva Instituto de EcologíaUNAMMéxico CityMexico

Endophytes infect living plant tissues without causing symptoms of disease.Indeed,many of them contribute to the resistance phenotype of their host.However,fungal endophytes are generally closely related to plant pathogens,fungi that either develop within living host tissue(biotrophic fungi)or that kill the host cells and then live in the dead tissue(necrotrophic fungi).We adopted a phylogenetic approach to investigate whether these strategies represent evolutionarily stable lifestyles and to elucidate their general phylogenetic relationships.We analysed 163 fungal strains for which we found information on the sequence of the 5.8S rRnA gene and the flanking internal transcribed spacer regions,the identity of the host plant and the concrete phenotypic outcome of the infection.A Maximum-Likelihood analysis combined with ancestral character mapping by maximum parsimony revealed that some fungal lineages had switched multiple times between a necrotrophic and an endophytic lifestyle.Ancestral character mapping indicated a minimum of four changes from an endophytic to a necrotrophic lifestyle,four changes in the opposite direction and eight changes among these lifestyles for which the direction could not be determined unambiguously.By contrast,biotrophs formed five clusters that did not contain necrotrophs or endophytes.Once biotrophy evolves there is apparently no regression to one of the other two lifestyles.We conclude that biotrophy usually represents a derived and evolutionarily stable trait,whereas fungi easily can switch between an endophytic and necrotrophic lifestyle at the evolutionary and even the ecological timescale.Future experimental studies should focus on the environmental or genetic changes that cause the rapid switches between these two phenotypically different lifestyles.

关键词： Disease expression Fungi Plant pathogens Phylogenetic effects

natural vegetation cover in the landscape and edge effects： differential responses of insect orders in a fragmented forest

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Insect Science 2017年第5期24卷 891-901页

作者： Ezequiel Gonzalez Adriana Salvo graciela Valladares Centro de Investigaciones Entomologicas de Cordoba IMBIV UNC CONICET FCEFyN Av. Velez Sarfield 1611 Cordoba CordobaX5000GMC Argentina

Human activities have led to global simplification of ecosystems, among which neotropical dry forests are some of the most threatened. Habitat loss as well as edge effects may affect insect communities. Here, we analyzed insects sampled with pan traps in 9 landscapes （at 5 scales, in 100-500 m diameter circles） comprising cultivated fields and Chaco Serrano forests, at overall community and taxonomic order level. In total 7043 specimens and 456 species of hexapods were captured, with abundance and richness being directly related to forest cover at 500 m and higher at edges in comparison with forest interior. Community composition also varied with forest cover and edge^interior location. Different responses were detected among the 8 dominant orders. Collembola, Hemiptera, and Orthoptera richness and^or abundance were positively related to forest cover at the larger scale, while Thysanoptera abundance increased with forest cover only at the edge. Hymenoptera abundance and richness were negatively related to forest cover at 100 m. Coleoptera, Diptera, and Hymenoptera were more diverse and abundant at the forest edge. The generally negative influence of forest loss on insect communities could have functional consequences for both natural and cultivated systems, and highlights the relevance of forest conservation. Higher diversity at the edges could result from the simultaneous presence of forest and matrix species, although ＂resource mapping＂ might be involved for orders that were richer and more abundant at edges. Adjacent crops could benefit from forest proximity since natural enemies and pollinators are well represented in the orders showing nositive edge effects.

关键词： Chaco Serrano edge effect forest cover habitat loss insects orders

Arthropods on plants in a fragmented neotropical dry forest： A functional analysis of area loss and edge effects

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Insect Science 2015年第1期22卷 129-138页

作者： Ezequiel Gonzalez Adriana Salvo graciela Valladares Centro de Investigaciones Entomol6gicas de C6rdoba (IMBIV - COnICET) and Universidad nacional de C6rdoba C6rdoba Argentina

Loss and fragmentation of natural ecosystems are widely recognized as the most important threats to biodiversity conservation, with neotropical dry forests among the most endangered ecosystems. Area and edge effects are major factors in fragmented landscapes. Here, we examine area and edge effects and their interaction, on ensembles of arthropods associated to native vegetation in a fragmented Chaco Serrano forest. We analyzed family richness and community composition of herbivores, predators, and parasitoids on three native plant species in 12 fragments of varying size and at edge/interior positions. We also looked for indicator families by using Indicator Species Analysis. Loss of family richness with the reduction of forest fragment area was observed for the three functional groups, with sirnilar magnitude. Herbivores were richer at the edges without interaction between edge and area effects, whereas predators were not affected by edge/interior position and parasitoid richness showed an interaction between area and position, with a steeper area slope at the edges. Family composition of herbivore, predator, and parasitoid assemblages was also affected by forest area and/or edge/interior situation. We found three indicator families for large remnants and five for edges. Our results support the key role of forest area for conservation of arthropods taxonomic and functional diversity in a highly threatened region, and emphasize the need to understand the interactions between area and edge effects on such diversity.

关键词： area loss Chaco Serrano edge effect forest arthropods functional groups habitat fragmentation

Hepatocellular carcinoma in patients with metabolic dysfunctionassociated fatty liver disease: Can we stratify at-risk populations?

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World Journal of Hepatology 2022年第2期14卷 354-371页

作者： Eduardo Fassio Fernando J Barreyro M Soledad Pérez Diana Dávila graciela Landeira Gisela Gualano Gabriela Ruffillo Hepatology Section Gastroenterology ServiceHospital Nacional Prof.Alejandro PosadasEl Palomar 1684Buenos AiresArgentina Biotechnology Institute of Misiones Faculty of Chemical and Natural SciencesNational University of MisionesPosadas N3300MisionesArgentina

Metabolic dysfunction-associated fatty liver disease(MAFLD)is a new nomenclature recently proposed by a panel of international experts so that the entity is defined based on positive criteria and linked to pathogenesis,replacing the traditional non-alcoholic fatty liver disease(nAFLD),a definition based on exclusion criteria.nAFLD/MAFLD is currently the most common form of chronic liver disease worldwide and is a growing risk factor for development of hepatocellular carcinoma(HCC).It is estimated than 25%of the global population have nAFLD and is projected to increase in the next years.Major Scientific Societies agree that surveillance for HCC should be indicated in patients with nAFLD/MAFLD and cirrhosis but differ in non-cirrhotic patients(including those with advanced fibrosis).Several studies have shown that the annual incidence rate of HCC in nAFLD-cirrhosis is greater than 1%,thus surveillance for HCC is costeffective.Risk factors that increase HCC incidence in these patients are male gender,older age,presence of diabetes and any degree of alcohol consumption.In non-cirrhotic patients,the incidence of HCC is much lower and variable,being a great challenge to stratify the risk of HCC in this group.Furthermore,large epidemiological studies based on the general population have shown that diabetes and obesity significantly increase risk of HCC.Some genetic variants may also play a role modifying the HCC occurrence among patients with nAFLD.The purpose of this review is to discuss the epidemiology,clinical and genetic risk factors that may influence the risk of HCC in nAFLD/MAFLD patients and propose screening strategy to translate into better patient care.

关键词： Hepatocellular carcinoma Metabolic dysfunction-associated fatty liver disease nonalcoholic fatty liver disease Surveillance for hepatocellular carcinoma Incidence of hepatocellular carcinoma nonalcoholic steatohepatitis