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Evaluación del uso de vibriófagos encapsulados en el alimento para el control de Vibrio parahaemolitycus causante de AHPND en el camarón Penaeus vannamei

Esther Imelda Ponce García (2023, [Tesis de maestría])

"Las enfermedades causadas por bacterias del género Vibrio en el cultivo de camarón son de gran importancia debido a su impacto negativo en la industria acuícola. Estas bacterias pueden causar diversas enfermedades en camarones, como la necrosis hepatopancreática aguda (AHPND). La fagoterapia es una alternativa para el biocontrol de estas bacterias patógenas que presenta importantes ventajas, como la alta especificidad a sus huéspedes, la replicación en el sitio de infección, y la capacidad de infectar a bacterias resistentes a antibióticos. Sin embargo, la estabilidad de los fagos en el sistema de cultivo es una preocupación latente, ya que los fagos presentan una estabilidad limitada en solución y experimentan una caída significativa en el título de fagos durante el procesamiento y almacenamiento. El método de encapsulación de bacteriófagos, un área que aún no se estudia del todo, se presenta como una potencial alternativa para atender esta problemática. En el presente estudio se evaluó la eficacia terapéutica de un cóctel de bacteriófagos (vB_Vp_PvVp05, vB_Vp_PvVp07 y vB_Vp_PvVp11), encapsulados en alginato de sodio comercial y de mediana viscosidad, pectina, carboxilmetilcelulosa, liposomas y liofilizado en pectina como agente de biocontrol de Vibrio parahaemolyticus para su uso en terapias fagicas pasiva y activa. Se observó que el encapsulado en alginato de sodio de mediana viscosidad presentó la mayor liberación de fagos activos y al momento de ser incorporado a alimento para camarón y horneados a 80 – 100°C, se mantuvo una concentración de 1.3 x105 UFP/g después de 100 días de almacenamiento. Para la evaluación de las terapias pasiva y activa se realizó una infección experimental en juveniles de Penaeus vannamei para conocer la efectividad de los encapsulados, utilizando para la terapia pasiva la cepa Vp M0904 y para la activa la cepa Vp M0605. El experimento de terapia pasiva mostró una mortalidad del 80.6% en los camarones a las 48 hpi (p > 0.05) y una concentración de 5 x102 UFC/mL de Vibrio spp. no fermentativos en TCBS. En el caso de la terapia activa no se presentó mortalidades, pero hubo una disminución de la concentración de Vibrio spp. no fermentativos en TCBS con 5.56 x101 UFC/mL a las 48 hpi (p < 0.05) y aumentó la densidad de vibriófagos en 1.4 x102 UFP/mL en el agua de los acuarios (p < 0.05)..."

"Diseases caused by bacteria of the Vibrio genus in shrimp farming are of great importance due to their negative impact on the aquaculture industry. These bacteria can cause various diseases in shrimp, such as acute hepatopancreatic necrosis disease (AHPND). Phage therapy is an alternative for the biocontrol of these pathogenic bacteria, offering significant advantages, including high specificity to their hosts, replication at the infection site, and the ability to infect antibiotic-resistant bacteria. However, the stability of phages in the farming system is a persistent concern, as phages have limited stability in solution and undergo a significant drop in phage titer during processing and storage. The method of bacteriophage encapsulation, an area that is not yet fully explored, emerges as a potential alternative to address this issue. In this study, the therapeutic efficacy of a cocktail of bacteriophages (vB_Vp_PvVp05, vB_Vp_PvVp07, and vB_Vp_PvVp11), encapsulated in commercial medium-viscosity sodium alginate, pectin, carboxymethylcellulose, liposomes, and lyophilized pectin, was evaluated as a biocontrol agent against Vibrio parahaemolyticus for use in passive and active phage therapies. It was observed that encapsulation in medium-viscosity sodium alginate showed the highest release of active phages, maintaining a concentration of 1.3 x 105 PFU/g after 100 days of storage when incorporated into shrimp feed and baked at 80–100°C.For the evaluation of passive and active therapies, an experimental infection was conducted on Penaeus vannamei juveniles to assess the effectiveness of the encapsulated phages. The passive therapy experiment showed a mortality rate of 80.6% in shrimp at 48 hpi (p > 0.05) and a concentration of 5 x 102 CFU/mL of non-fermentative Vibrio spp. on TCBS agar. In the case of active therapy, no mortalities were observed, but there was a decrease in the concentration of non-fermentative Vibrio sp. on TCBS agar to 5.56 x 101 CFU/mL at 48 hpi (p < 0.05), and the density of vibriophages increased to 1.4 x 102 PFU/mL in the aquarium water (p < 0.05). It was determined that passive therapy offered no advantage for the control of Vibrio parahaemolyticus, unlike active therapy, which proved to be effective in controlling this bacterium."

vibriófagos, encapsulado, Penaeus vannamei, terapia activa, terapia pasiva vibriophages, encapsulated, active therapy, passive therapy BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA MICROBIOLOGÍA BACTERIÓFAGOS BACTERIÓFAGOS

Hacia el desarrollo de un nuevo antiparasitario basado en células en suspensión de Carica papaya

CYNTHIA ALEJANDRA GUZMÁN MEDINA (2023, [Tesis de doctorado])

Las enfermedades parasitarias son un problema de salud pública que afectan a más de la

quinta parte de la población a nivel mundial. Además de la morbilidad que generan, sino

son tratadas y controladas de manera adecuada pueden llegar a causar la muerte.

En el mercado existen diferentes antiparasitarios comerciales, que si bien son efectivos,

presentan diferentes efectos adversos tanto para el individuo parasitado (i.e. destrucción

de la microbiota intestinal) como para el medio ambiente. Este panorama señala la

relevancia de desarrollar tratamientos antiparasitarios más amigables con el ambiente y con

menores efectos adversos que estén disponibles actualmente en el mercado. Productos

obtenidos a partir de plantas con propiedades anti-parasitarias, cultivadas in vitro en

condiciones controladas, podrían representar una alternativa realista. Entre ellas figura la

planta Carica papaya, especie de zonas tropicales y subtropicales del planeta a cuyos frutos

se les adjudica actividades antiparasitarias. Estas propiedades se atribuyen a algunos de

sus compuestos concentrados en el latex y en las semillas como la papaina, la

quimiopapaína, la lisozima, la glicil-endopeptidasa, la proteasa de cisteína y el benzil-

isotiocinato.

El objetivo del presente trabajo fue evaluar la actividad antiparasitaria in vitro e in vivo de

un conjunto de callos y líneas de células de papaya de Carica papaya contra cisticercos de

Taenia crassiceps (cestodo) y contra trofozoitos de Entamoeba histolytica (protozoario). Los

extractos acuosos obtenidos a partir de callos y células cultivados en placa o en suspensión,

respectivamente, de las diferentes líneas de papaya revelaron alta capacidad cisticida

(>98% de mortalidad) in vitro contra cisticercos de Taenia crassiceps. En la evaluación in

vivo la línea no transformada obtuvo mayor efecto cisticida a 10mg/mL reduciendo el

número de cisticercos gemantes y aumentando los cisticercos calcificados en niveles

similares a los obtenidos utilizando antiparasitarios comerciales (albendazol y niclosamida).

Las líneas transformadas y sin transformar de papaya evaluadas indujeron una alta

capacidad amebicida (97% de mortalidad) in vitro contra trofozoitos de Entamoeba

histolytica. Las diferentes líneas transformadas y sin transformar de papaya redujeron

significativamente el número de abscesos amebianos y previnieron la hepatomegalia de

manera no significativamente diferente que el anti-parasitario comercial (metronidazol).

Los resultados generados en el presente estudio señalan al extracto acuoso obtenido a

partir de cultivos en suspensión de células de papaya transformada y no transformada

indujeron alto nivel de protección in vitro e in vivo por lo tanto; este es un producto efectivo

para el tratamiento de la cisticercosis y la amebiasis.

Parasitic diseases are a public health problem that affect more than a fifth of the population

worldwide. Additionally, and along with the morbidity the produce, they can cause death if

they are not treated and controlled adequately.

There are different commercial antiparasitic on the market which, although effective,

present different adverse effects both for the individual (i.e., destruction of the intestinal

microbiota) and for the environment alike. This panorama points out the relevance of

developing more environmentally friendly antiparasitic treatments with fewer adverse effects

than the ones currently available on the market. Products obtained from plants with anti-

parasitic properties, grown in vitro under controlled conditions, could represent a realistic

alternative. Among them is the Carica papaya, a species from tropical and subtropical areas

of the planet whose fruits are believed to have antiparasitic activities. These properties are attributed to some of its compounds concentrated in the latex and seeds such as papain,

chymopapain, lysozyme, glycyl-endopeptidase, cysteine-proteinase and benzyl-

isothiocyanate.

The objective of the present work is to evaluate the in vitro and in vivo antiparasitic activity

of a set of papaya callus and cell lines from Carica papaya against cysticerci of Taenia

crassiceps (cestode) and against trophozoites of Entamoeba histolytica (protozoan). The

aqueous extracts obtained from callus and cells cultured in plates or in suspension,

respectively, of the different papaya lines revealed high cysticidal capacity (>98% mortality)

in vitro against Taenia crassiceps cysticerci. Meanwhile, in the in vivo evaluation, the non-

transformed line obtained a greater cysticidal effect at 10 mg/mL, reducing the number of

budding cysticerci and increasing calcified cysticerci at levels like those obtained using

commercial antiparasitic (albendazole and niclosamide). The papaya lines evaluated

induced a high amoebicidal capacity (97% mortality) in vitro against Entamoeba histolytica

trophozoites. The different papaya lines significantly reduced the number of amoebic

abscesses and prevented hepatomegaly in a non-significantly different manner than the

commercial anti-parasitic (metronidazole).

The results produced in this thesis indicate that the aqueous extract obtained from

suspension cultures of transformed and non-transformed papaya cells induced a high level

of protection in vitro and in vivo. Therefore, this may represent an effective product for the

treatment of cysticercosis and amoebiasis.

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS Carica papaya, antiparasitario, células en suspensión, T. crassiceps, E. histolytica. Carica papaya, antiparasitic, in-suspension cells, T. crassiceps, E. histolytica.

Chronic toxicity of shrimp feed added with silver nanoparticles (Argovit-4®) in Litopenaeus vannamei and immune response to white spot syndrome virus infection

Carlos Rosendo Romo Quiñonez Píndaro Álvarez Ruiz CLAUDIO HUMBERTO MEJIA RUIZ NINA BOGDANCHIKOVA Alexey Pestryakov CARINA GAMEZ JIMENEZ WENCESLAO VALENZUELA QUIÑONEZ Magnolia Montoya Mejía EUSEBIO NAVA PEREZ (2022, [Artículo])

"In recent years, the application of silver nanoparticles (AgNPs) as antibacterial compounds has been widely used in human and veterinary medicine. In this work, we investigated the effects of AgNPs (Argovit-4 R ) as feed additives (feed-AgNPs) on shrimp (Litopenaeus vannamei) using three different methods: 1) chronic toxicity after 28 days of feeding, 2) Effects against white spot syndrome virus (WSSV) challenged by oral route, and 3) transcriptional responses of immune-related genes (PAP, ProPO, CTL-3, Crustin, PEN3, and PEN4) following WSSV infection. The results showed that the feed-AgNPs did not interfere with the growth and survival of shrimp. Also, mild lesions in the hepatopancreas were recorded, proportional to the frequency of the feed-AgNP supply. Challenge test versus WSSV showed that feeding every 7 days with feed-AgNPs reduced mortality, reaching a survival rate of 53%, compared to the survival rates observed in groups fed every 4 days, daily and control groups of feed-AgNPs for the 30%, 10%, and 7% groups, respectively. Feed-AgNPs negatively regulated the expression of PAP, ProPO, and Crustin genes after 28 days of treatment and altered the transcriptional responses of PAP, ProPO, CTL-3, and Crustin after WSSV exposure. The results showed that weekly feeding-AgNPs could partially prevent WSSV infection in shrimp culture. However, whether or not transcriptional responses against pathogens are advantageous remains to be elucidated."

Silver nanoparticles, Shrimp, Aquaculture, Chronic toxicity, WSSV, AgNP, Argovit, Litopenaeus vannamei , Silver fed, White spot syndrome virus BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA INMUNOLOGÍA INMUNIZACIÓN INMUNIZACIÓN

Enhancement of antibiotics antimicrobial activity due to the silver nanoparticles impact on the cell membrane

Roberto Vazquez-Munoz (2019, [Artículo])

The ability of microorganisms to generate resistance outcompetes with the generation of new and efficient antibiotics; therefore, it is critical to develop novel antibiotic agents and treatments to control bacterial infections. An alternative to this worldwide problem is the use of nanomaterials with antimicrobial properties. Silver nanoparticles (AgNPs) have been extensively studied due to their antimicrobial effect in different organisms. In this work, the synergistic antimicrobial effect of AgNPs and conventional antibiotics was assessed in Gram-positive and Gram-negative bacteria. AgNPs minimal inhibitory concentration was 10–12 μg mL-1 in all bacterial strains tested, regardless of their different susceptibility against antibiotics. Interestingly, a synergistic antimicrobial effect was observed when combining AgNPs and kanamycin according to the fractional inhibitory concentration index, FICI: &lt;0.5), an additive effect by combining AgNPs and chloramphenicol (FICI: 0.5 to 1), whereas no effect was found with AgNPs and β-lactam antibiotics combinations. Flow cytometry and TEM analysis showed that sublethal concentrations of AgNPs (6–7 μg mL-1) altered the bacterial membrane potential and caused ultrastructural damage, increasing the cell membrane permeability. No chemical interactions between AgNPs and antibiotics were detected. We propose an experimental supported mechanism of action by which combinatorial effect of antimicrobials drives synergy depending on their specific target, facilitated by membrane alterations generated by AgNPs. Our results provide a deeper understanding about the synergistic mechanism of AgNPs and antibiotics, aiming to combat antimicrobial infections efficiently, especially those by multi-drug resistant microorganisms, in order to mitigate the current crisis due to antibiotic resistance. © 2019 Vazquez-Muñoz et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

ampicillin, antibiotic agent, aztreonam, beta lactam antibiotic, biapenem, chloramphenicol, kanamycin, silver nanoparticle, silver nitrate, antiinfective agent, metal nanoparticle, silver, antibiotic sensitivity, antimicrobial activity, Article, bact BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOFÍSICA BIOFÍSICA

Desarrollo y comercialización de adyuvantes herbolarios como alternativa terapéutica para el tratamiento del síndrome metabólico en adultos mexicanos. Evaluación de solicitud de patente y registro sanitario

SYLVIA ADRIANA PINAL CALVILLO (2023, [Tesis de maestría])

Este trabajo de tesis parte de la creciente preocupación global sobre la Epidemia

Metabólica, enfocándose en su prevalencia, impacto económico y las perspectivas

futuras en México. Se centra en la interconexión entre enfermedades metabólicas,

factores de riesgo compartidos y la respuesta a intervenciones comunes,

destacando la obesidad, diabetes y síndrome metabólico como ejes centrales.

Adicionalmente, examina la Medicina Ancestral y la estandarización en la

producción de remedios herbolarios como estrategias potenciales para mitigar esta

crisis.

El trabajo revisa los antecedentes de la Medicina Tradicional según la Organización

Mundial de la Salud (OMS), su uso en condiciones metabólicas, y su integración en

sistemas de salud. Se presta especial atención al uso de plantas medicinales en

México y a nivel global, resaltando la transferencia intercultural de conocimientos

herbolarios en la era de la globalización.

En el marco general, se establecen los objetivos del estudio y se detalla la

caracterización de productos herbales específicos para el tratamiento del síndrome

metabólico, se centra en el uso sinérgico de: Syzigium cumini, Coix lacryma-jobi, y

Mossanona depressa. Se analizan sus propiedades farmacológicas y usos en el

tratamiento de la diabetes y el síndrome metabólico.

La sección de formalización comercial aborda la constitución de la sociedad, los

registros ante el Instituto Mexicano de Propiedad Intelectual (IMPI) y la Comisión

Federal para la Protección contra Riesgos a la Salud (COFEPRIS), la determinación

de patentabilidad, y las estrategias de protección de propiedad intelectual.

Finalmente, el estudio concluye con recomendaciones para la mejora regulatoria en

este campo y detalla la tramitología necesaria para la implementación de estas

estrategias. La investigación subraya la importancia de integrar la medicina

tradicional en los sistemas de salud modernos para combatir la epidemia

metabólica, especialmente en contextos como el de México.

BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA Epidemia metabólica, medicina ancestral México, Herbario Mundial, obesidad, diabetes, síndrome metabólico, tratamiento herbolario, factores riesgo metabólicos, intervenciones epidemia metabólica, carga económica Salud México, remedios naturales diabetes, integración medicina tradicional, OMS Medicina Tradicional, plantas medicinales metabólicas, Syzigium cumini, Coix lacryma-jobi, Mossanona depressa, Propiedad Intelectual Herbolarios, Registro COFEPRIS, Patentabilidad Productos Naturales, Legislación Mexicana Salud, Mejora Regulatoria Medicina Tradicional.

Whole-genome comparison between reference sequences and oyster Vibrio vulnificus C-genotype strains

CARLOS ABRAHAM GUERRERO RUIZ (2019, [Artículo])

Whole-genome sequences of Vibrio vulnificus clinical genotype (C-genotype) from the CICESE Culture Collection, isolated from oysters, were compared with reference sequences of CMCP6 and YJ016 V. vulnificus C-genotype strains of clinical origin. The RAST web server estimated the whole genome to be ~4.8 Mb in CICESE strain 316 and ~4.7 Mb in CICESE strain 325. No plasmids were detected in the CICESE strains. Based on a phylogenetic tree that was constructed with the whole-genome results, we observed high similarity between the reference sequences and oyster C-genotype isolates and a sharp contrast with environmental genotype (E-genotype) reference sequences, indicating that the differences between the C- and E-genotypes do not necessarily correspond to their isolation origin. The CICESE strains share 3488 genes (63.2%) with the YJ016 strain and 3500 genes (63.9%) with the CMCP6 strain. A total of 237 pathogenicity associated genes were selected from reference clinical strains, where—92 genes were from CMCP6, 126 genes from YJ016, and 19 from MO6-24/ O; the presence or absence of these genes was recorded for the CICESE strains. Of the 92 genes that were selected for CMCP6, 67 were present in both CICESE strains, as were as 86 of the 126 YJ016 genes and 13 of the 19 MO6-24/O genes. The detection of elements that are related to virulence in CICESE strains—such as the RTX gene cluster, vvhA and vvpE, the type IV pili cluster, the XII genomic island, and the viuB genes, suggests that environmental isolates with the C-genotype, have significant potential for infection. © 2019 Guerrero et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Article, bacterial gene, bacterial strain, bacterial virulence, comparative study, controlled study, gene cluster, gene identification, genomic island, genotype, nonhuman, phylogenetic tree, sequence analysis, strain identification, Vibrio vulnificus BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA GENÉTICA GENÉTICA

Effect of antimicrobial nanocomposites on Vibrio cholerae lifestyles: Pellicle biofilm, planktonic and surface-attached biofilm

ANAID MEZA VILLEZCAS (2019, [Artículo])

Vibrio cholerae is an important human pathogen causing intestinal disease with a high incidence in developing countries. V. cholerae can switch between planktonic and biofilm lifestyles. Biofilm formation is determinant for transmission, virulence and antibiotic resistance. Due to the enhanced antibiotic resistance observed by bacterial pathogens, antimicrobial nanomaterials have been used to combat infections by stopping bacterial growth and preventing biofilm formation. In this study, the effect of the nanocomposites zeolite-embedded silver (Ag), copper (Cu), or zinc (Zn) nanoparticles (NPs) was evaluated in V. cholerae planktonic cells, and in two biofilm states: pellicle biofilm (PB), formed between air-liquid interphase, and surface-attached biofilm (SB), formed at solid-liquid interfaces. Each nanocomposite type had a distinctive antimicrobial effect altering each V. cholerae lifestyles differently. The ZEO-AgNPs nanocomposite inhibited PB formation at 4 μg/ml, and prevented SB formation and eliminated planktonic cells at 8 μg/ml. In contrast, the nanocomposites ZEO-CuNPs and ZEO-ZnNPs affect V. cholerae viability but did not completely avoid bacterial growth. At transcriptional level, depending on the nanoparticles and biofilm type, nanocomposites modified the relative expression of the vpsL, rbmA and bap1, genes involved in biofilm formation. Furthermore, the relative abundance of the outer membrane proteins OmpT, OmpU, OmpA and OmpW also differs among treatments in PB and SB. This work provides a basis for further study of the nanomaterials effect at structural, genetic and proteomic levels to understand the response mechanisms of V. cholerae against metallic nanoparticles. © 2019 Meza-Villezcas et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

bacterial protein, copper nanoparticle, nanocomposite, OmpT protein, OmpU protein, OmpW protein, outer membrane protein A, silver nanoparticle, unclassified drug, zeolite, zinc nanoparticle, antiinfective agent, copper, metal nanoparticle, nanocompos BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA MICROBIOLOGÍA MICROBIOLOGÍA

The Pacific harbor seal gut microbiota in Mexico: Its relationship with diet and functional inferences

ARLETTE MARIMAR PACHECO SANDOVAL (2019, [Artículo])

Diet is a primary driver of the composition of gut microbiota and is considered one of the main routes of microbial colonization. Prey identification is fundamental for correlating the diet with the presence of particular microbial groups. The present study examined how diet influenced the composition and function of the gut microbiota of the Pacific harbor seal (Phoca vitulina richardii) in order to better understand the role of prey consumption in shaping its microbiota. This species is a good indicator of the quality of the local environment due to both its foraging and haul-out site fidelity. DNA was extracted from 20 fecal samples collected from five harbor seal colonies located in Baja California, Mexico. The V4 region of 16S rRNA gene was amplified and sequenced using the Illumina technology. Results showed that the gut microbiota of the harbor seals was dominated by the phyla Firmicutes (37%), Bacteroidetes (26%) and Fusobacteria (26%) and revealed significant differences in its composition among the colonies. Funtional analysis using the PICRUSt software suggests a high number of pathways involved in the basal metabolism, such as those for carbohydrates (22%) and amino acids (20%), and those related to the degradation of persistent environmental pollutants. In addition, a DNA metabarcoding analysis of the same samples, via the amplification and sequencing of the mtRNA 16S and rRNA 18S genes, was used to identify the prey consumed by harbor seals revealing the consumption of prey with mainly demersal habits. Functional redundancy in the seal gut microbiota was observed, irrespective of diet or location. Our results indicate that the frequency of occurrence of specific prey in the harbor seal diet plays an important role in shaping the composition of the gut microbiota of harbor seals by influencing the relative abundance of specific groups of gut microorganisms. A significant relationship was found among diet, gut microbiota composition and OTUs assigned to a particular metabolic pathway. © 2019 Pacheco-Sandoval et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

RNA 16S, RNA 18S, amino acid analysis, animal food, Article, bacterium colony, Bacteroidetes, basal metabolic rate, biodegradation, controlled study, DNA barcoding, feces analysis, Firmicutes, Fusobacteria, intestine flora, metabolism, Mexico, microb BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) BIOLOGÍA ANIMAL (ZOOLOGÍA)