Chiltepin is a semi-cultivated plant of high commercial value and represents a valuable genetic r... more Chiltepin is a semi-cultivated plant of high commercial value and represents a valuable genetic resource. However, several factors, such as drought, limit its production. Treatment with plant growth-promoting bacteria (PGPBs) is an alternative to mitigate drought stress. The present study aimed to evaluate the capacity of Bacillus spp, isolated from soils, to promote growth and induce tolerance to drought stress in chiltepin. A completely random design was established, and the Scott-Knott test was used (α = 0.05). The treated seeds improved germination parameters with increases of 46.42% in Germination Rate (GR), 22.56% in Mean Speed of Germination (MSG), 22.19% in Germination Speed Index (GSI), 65.16% in Vigor Index (VI), and 100.14% in Germination Index (GI). Furthermore, they reduced MGT (Mean Germination Time) by 5.63%. All isolates could solubilize phosphorus and zinc and produce ammonium, siderophores, and exopolysaccharides. Moreover, Bacillus spp. isolates showed resistance ...
In Vitro Cellular & Developmental Biology - Animal, 2022
During in vitro maturation (IVM), the compact structure of cumulus-oocyte complexes (COCs) is vit... more During in vitro maturation (IVM), the compact structure of cumulus-oocyte complexes (COCs) is vital for oocyte competence acquisition. Intermedin/Adrenomedullin-2 (IMD/ADM2) binds to the receptor RAMP (1, 2, or 3):CLR. Recently, it was demonstrated that IMD/ADM2 stimulates oocyte competence and improves bovine embryo quality. Therefore, this study aimed to examine the IMD/ADM2 as a secretory factor controlling COCs conformation for oocyte maturation. The results showed that traditional M-CDM medium induced in COCs the Imd/Adm2 gene expression during IVM and produced IMD/ADM2 peptide secretion. Furthermore, after IVM, in the oocytes, the expression of ramps (1, 2, or 3) and clr was demolished, and RAMPs and CLR proteins were decreased, with a negative Pearson correlation. These results suggest that RAMPs and CLR are synthesized and stored during oocyte maturation. Supplementing the M-CDM with α-RAMP1 or α-IMD/ADM2 antibodies elicits a negative effect (P < 0.05) in COCs compaction. Blocking the IMD/ADM2 signaling pathway with any α-RAMPs or α-CLR antibodies produces a similar lower yield of oocytes in metaphase II (P > 0.05) but was lower than control culture medium (P < 0.05). In conclusion, when COCs are cultured with M-CDM, the IMD/ADM2 becomes expressed and secreted. In turn, it acts as a ligand preferentially to RAMP1:CLR or RAMP3:CLR, present in cumulus cells and oocytes. Sequentially, COCs compact structure is conformed to promote an adequate bidirectional communication that conduces the oocytes' maturation.
Silver nanoparticles (AgNPs) have captured the interest of the scientific community as a potentia... more Silver nanoparticles (AgNPs) have captured the interest of the scientific community as a potential antimicrobial agent. However, the mechanisms by which AgNPs cause cellular damage remain unclear. The objective of this study was to evaluate the inhibitory effects of AgNPs on representative pathogenic microorganisms, including Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans and Coniophora eremophila. The results showed that AgNPs have inhibitory effect against P. aeruginosa, S. aureus (1 and 2 g/mL respectively), and C. albicans (140 g/mL), in solid media. AgNPs against C. eremophila showed a lethal dose 50 (LD50) of 30 g/mL. However, in liquid media, higher concentrations were necessary for growth inhibition in all cases. It was also observed that bacteria-secreted exopolysaccharide biofilms decreasing the toxicity of the AgNPs. Structural damage in AgNP-exposed C. albicans and P. aeruginosa was demonstrated by scanning electron microscopy. In addition, the AgNPs had an inhibitory effect on lipase and Lactic dehydrogenase (LDH) activity. The results presented in this study suggest that enzyme inhibition and cell wall structural damage explain the observed growth inhibition of the tested microorganisms. Our results suggest that AgNPs may be useful for the production of antibacterial materials and the prevention of wood decay.
International microbiology : the official journal of the Spanish Society for Microbiology, 2015
Rotavirus vaccine was developed using the most prominent G and P genotypes circulating in childre... more Rotavirus vaccine was developed using the most prominent G and P genotypes circulating in children population. Therefore, severe gastroenteritis has been reduced around the world. This study investigated the G and P rotavirus genotypes circulating in children from two hospitals in the city of Chihuahua, Mexico. Additionally, polyclonal antibodies against Rotavirus Wa strain were used to determine their homotypic and heterotypic reactivity to both P[8] and P[4] genotypes. G1, G2, and G3 VP7 genotypes and P[8] and P[4] VP4 genotypes were detected in common and uncommon combinations as well as mixed infectious. The predominant combination was G1P[8]. Phylogenetic analysis of VP4 gene revealed the presence of P[8]-1 and P[8]-3 lineages of P[8] genotype and P[4]-5 lineage of P[4] genotype. All but five G1P[8] rotavirus were detected by polyclonal anti-Rotavirus Wa strain. Mutation analysis revealed differences in three of the four neutralizing epitopes previously reported to VP8* subunit...
Background Bacillus genus has been used in horticultural crops as a biocontrol agent against inse... more Background Bacillus genus has been used in horticultural crops as a biocontrol agent against insect pests, microbial phytopathogens, and plant growth-promoting bacteria (PGPB), representing an alternative to agrochemicals. In particular, B. cereus (Bc) and B. thuringiensis (Bt) have been studied for their fungicidal and insecticidal activities. However, their use as biofertilizer formulations and biocontrol agents against phytopathogenic bacteria is limited. Objective To evaluate Bc and Bt formulations as PGPB and biocontrol agents against the bacterial spot agent Xanthomonas euvesicatoria (Xe) in greenhouse-grown chili peppers. Methods Bc and Bt isolates obtained from soil samples were identified and characterized using conventional biochemical and multiplex PCR identification methods. Bioassays to determine Bc and Bt isolates potential as PGPB were evaluated on chili pepper seedlings in seedbeds. In addition, formulations based on Bc (F-BC26 and F-BC08) and Bt (F-BT24) strains wer...
Background Xanthomonas spp. causes bacterial spot disease, which reduces quality and yield of pep... more Background Xanthomonas spp. causes bacterial spot disease, which reduces quality and yield of pepper crops in Mexico. Identification of phytopathogen species is necessary to implement more effective control strategies. Objective The aim of this study was to isolate and identify infecting Xanthomonas species in South Central Chihuahua pepper-producing areas. Methods Diseased plants were collected from 30 cultivation lots and bacteria were isolated from damaged tissues. Potential causative agents were isolated, identified, and characterized by biochemical and molecular analysis. Pathogenicity tests from each isolate were then performed on 30-d-old pepper seedlings, exposing five leaves to 10 µL of 1 × 108 CFU/mL bacterial suspensions of each isolate, using sterile distilled water as a control. Disease severity was determined after 10 d by calculating leaf damage percentage. Furthermore, we evaluated the susceptibility of the highest bacterial spot severity-causing isolates (13 isolate...
Macro- and microorganism activities are important for the effectiveness of the slow sand filtrati... more Macro- and microorganism activities are important for the effectiveness of the slow sand filtration (SSF), where native microorganisms remove contaminants mainly by substrate competition, predation, and antagonism. The aim of the present study was to evaluate the addition of the oligodynamic metals iron, copper, and brass, inserted separately into SSF to enhance pollutant removal in water samples. Four laboratory-scale SSFs were built and tested: control, iron, copper, and brass. Water analysis included physicochemical evaluation, total and fecal coliform quantification. An analysis on microbial communities in the SSFs schmutzdecke was achieved by using 16S rRNA amplification, the Illumina MiSeq platform, and the QIIME bioinformatics software. The results demonstrated that inorganic and organic contaminants such as coliforms were removed up to 90%. The addition of metals had no significant effect (p > 0.05) on the other parameters. The microbial community analysis demonstrated di...
Experimental studies have shown that prenatal exposure to lead (Pb) produces morphological change... more Experimental studies have shown that prenatal exposure to lead (Pb) produces morphological changes related to extracellular matrix remodelling. To analyse whether the matrix metalloproteinases (MMPs), particularly MMP-2, MMP-9, and the tissue inhibitor of metalloproteinases-2 (TIMP-2), are associated with morphological alterations found in placentas, the expression of these enzymes was evaluated by immunohistochemical and image analyses in placentas of women with histories of environmental exposure to Pb. The median maternal concentration of Pb in blood was 4.68 µg/dL ([Formula: see text] = 5.85 ± 6.48 µg/dL). Significant differences related to the exposure to Pb were not detected in newborn or placenta weight. MMP-2, MMP-9, and TIMP-2 were expressed in the syncytiotrophoblast layer of placental villi. A significant increase in both MMP-2 and MMP-9 was observed in placentas of women with concentrations of Pb in blood ≥4.68 µg/dL ( p = 0.01 and 0.03 for MMP-2 and MMP-9, respectively)...
Inorganic arsenic (iAs) exposure induces a decrease in glucose type 4 transporter (GLUT4) express... more Inorganic arsenic (iAs) exposure induces a decrease in glucose type 4 transporter (GLUT4) expression on the adipocyte membrane, which may be related to premature births and low birth weight infants in women exposed to iAs at reproductive age. The aim of this study was to analyze the effect of sodium arsenite (NaAsO2) exposure on GLUT1, GLUT3, and GLUT4 protein expression and on placental morphology. Female Balb/c mice (n=15) were exposed to 0, 12, and 20 ppm of NaAsO2in drinking water from 8th to 18th day of gestation. Morphological changes and GLUT1, GLUT3, and GLUT4 expression were evaluated in placentas by immunohistochemical and image analysis and correlated with iAs and arsenical species concentration, which were quantified by atomic absorption spectroscopy. NaAsO2exposure induced a significant decrease in fetal and placental weight (P<0.01) and increases in infarctions and vascular congestion. Whereas GLUT1 expression was unchanged in placentas from exposed group, GLUT3 exp...
Chiltepin is a semi-cultivated plant of high commercial value and represents a valuable genetic r... more Chiltepin is a semi-cultivated plant of high commercial value and represents a valuable genetic resource. However, several factors, such as drought, limit its production. Treatment with plant growth-promoting bacteria (PGPBs) is an alternative to mitigate drought stress. The present study aimed to evaluate the capacity of Bacillus spp, isolated from soils, to promote growth and induce tolerance to drought stress in chiltepin. A completely random design was established, and the Scott-Knott test was used (α = 0.05). The treated seeds improved germination parameters with increases of 46.42% in Germination Rate (GR), 22.56% in Mean Speed of Germination (MSG), 22.19% in Germination Speed Index (GSI), 65.16% in Vigor Index (VI), and 100.14% in Germination Index (GI). Furthermore, they reduced MGT (Mean Germination Time) by 5.63%. All isolates could solubilize phosphorus and zinc and produce ammonium, siderophores, and exopolysaccharides. Moreover, Bacillus spp. isolates showed resistance ...
In Vitro Cellular & Developmental Biology - Animal, 2022
During in vitro maturation (IVM), the compact structure of cumulus-oocyte complexes (COCs) is vit... more During in vitro maturation (IVM), the compact structure of cumulus-oocyte complexes (COCs) is vital for oocyte competence acquisition. Intermedin/Adrenomedullin-2 (IMD/ADM2) binds to the receptor RAMP (1, 2, or 3):CLR. Recently, it was demonstrated that IMD/ADM2 stimulates oocyte competence and improves bovine embryo quality. Therefore, this study aimed to examine the IMD/ADM2 as a secretory factor controlling COCs conformation for oocyte maturation. The results showed that traditional M-CDM medium induced in COCs the Imd/Adm2 gene expression during IVM and produced IMD/ADM2 peptide secretion. Furthermore, after IVM, in the oocytes, the expression of ramps (1, 2, or 3) and clr was demolished, and RAMPs and CLR proteins were decreased, with a negative Pearson correlation. These results suggest that RAMPs and CLR are synthesized and stored during oocyte maturation. Supplementing the M-CDM with α-RAMP1 or α-IMD/ADM2 antibodies elicits a negative effect (P < 0.05) in COCs compaction. Blocking the IMD/ADM2 signaling pathway with any α-RAMPs or α-CLR antibodies produces a similar lower yield of oocytes in metaphase II (P > 0.05) but was lower than control culture medium (P < 0.05). In conclusion, when COCs are cultured with M-CDM, the IMD/ADM2 becomes expressed and secreted. In turn, it acts as a ligand preferentially to RAMP1:CLR or RAMP3:CLR, present in cumulus cells and oocytes. Sequentially, COCs compact structure is conformed to promote an adequate bidirectional communication that conduces the oocytes' maturation.
Silver nanoparticles (AgNPs) have captured the interest of the scientific community as a potentia... more Silver nanoparticles (AgNPs) have captured the interest of the scientific community as a potential antimicrobial agent. However, the mechanisms by which AgNPs cause cellular damage remain unclear. The objective of this study was to evaluate the inhibitory effects of AgNPs on representative pathogenic microorganisms, including Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans and Coniophora eremophila. The results showed that AgNPs have inhibitory effect against P. aeruginosa, S. aureus (1 and 2 g/mL respectively), and C. albicans (140 g/mL), in solid media. AgNPs against C. eremophila showed a lethal dose 50 (LD50) of 30 g/mL. However, in liquid media, higher concentrations were necessary for growth inhibition in all cases. It was also observed that bacteria-secreted exopolysaccharide biofilms decreasing the toxicity of the AgNPs. Structural damage in AgNP-exposed C. albicans and P. aeruginosa was demonstrated by scanning electron microscopy. In addition, the AgNPs had an inhibitory effect on lipase and Lactic dehydrogenase (LDH) activity. The results presented in this study suggest that enzyme inhibition and cell wall structural damage explain the observed growth inhibition of the tested microorganisms. Our results suggest that AgNPs may be useful for the production of antibacterial materials and the prevention of wood decay.
International microbiology : the official journal of the Spanish Society for Microbiology, 2015
Rotavirus vaccine was developed using the most prominent G and P genotypes circulating in childre... more Rotavirus vaccine was developed using the most prominent G and P genotypes circulating in children population. Therefore, severe gastroenteritis has been reduced around the world. This study investigated the G and P rotavirus genotypes circulating in children from two hospitals in the city of Chihuahua, Mexico. Additionally, polyclonal antibodies against Rotavirus Wa strain were used to determine their homotypic and heterotypic reactivity to both P[8] and P[4] genotypes. G1, G2, and G3 VP7 genotypes and P[8] and P[4] VP4 genotypes were detected in common and uncommon combinations as well as mixed infectious. The predominant combination was G1P[8]. Phylogenetic analysis of VP4 gene revealed the presence of P[8]-1 and P[8]-3 lineages of P[8] genotype and P[4]-5 lineage of P[4] genotype. All but five G1P[8] rotavirus were detected by polyclonal anti-Rotavirus Wa strain. Mutation analysis revealed differences in three of the four neutralizing epitopes previously reported to VP8* subunit...
Background Bacillus genus has been used in horticultural crops as a biocontrol agent against inse... more Background Bacillus genus has been used in horticultural crops as a biocontrol agent against insect pests, microbial phytopathogens, and plant growth-promoting bacteria (PGPB), representing an alternative to agrochemicals. In particular, B. cereus (Bc) and B. thuringiensis (Bt) have been studied for their fungicidal and insecticidal activities. However, their use as biofertilizer formulations and biocontrol agents against phytopathogenic bacteria is limited. Objective To evaluate Bc and Bt formulations as PGPB and biocontrol agents against the bacterial spot agent Xanthomonas euvesicatoria (Xe) in greenhouse-grown chili peppers. Methods Bc and Bt isolates obtained from soil samples were identified and characterized using conventional biochemical and multiplex PCR identification methods. Bioassays to determine Bc and Bt isolates potential as PGPB were evaluated on chili pepper seedlings in seedbeds. In addition, formulations based on Bc (F-BC26 and F-BC08) and Bt (F-BT24) strains wer...
Background Xanthomonas spp. causes bacterial spot disease, which reduces quality and yield of pep... more Background Xanthomonas spp. causes bacterial spot disease, which reduces quality and yield of pepper crops in Mexico. Identification of phytopathogen species is necessary to implement more effective control strategies. Objective The aim of this study was to isolate and identify infecting Xanthomonas species in South Central Chihuahua pepper-producing areas. Methods Diseased plants were collected from 30 cultivation lots and bacteria were isolated from damaged tissues. Potential causative agents were isolated, identified, and characterized by biochemical and molecular analysis. Pathogenicity tests from each isolate were then performed on 30-d-old pepper seedlings, exposing five leaves to 10 µL of 1 × 108 CFU/mL bacterial suspensions of each isolate, using sterile distilled water as a control. Disease severity was determined after 10 d by calculating leaf damage percentage. Furthermore, we evaluated the susceptibility of the highest bacterial spot severity-causing isolates (13 isolate...
Macro- and microorganism activities are important for the effectiveness of the slow sand filtrati... more Macro- and microorganism activities are important for the effectiveness of the slow sand filtration (SSF), where native microorganisms remove contaminants mainly by substrate competition, predation, and antagonism. The aim of the present study was to evaluate the addition of the oligodynamic metals iron, copper, and brass, inserted separately into SSF to enhance pollutant removal in water samples. Four laboratory-scale SSFs were built and tested: control, iron, copper, and brass. Water analysis included physicochemical evaluation, total and fecal coliform quantification. An analysis on microbial communities in the SSFs schmutzdecke was achieved by using 16S rRNA amplification, the Illumina MiSeq platform, and the QIIME bioinformatics software. The results demonstrated that inorganic and organic contaminants such as coliforms were removed up to 90%. The addition of metals had no significant effect (p > 0.05) on the other parameters. The microbial community analysis demonstrated di...
Experimental studies have shown that prenatal exposure to lead (Pb) produces morphological change... more Experimental studies have shown that prenatal exposure to lead (Pb) produces morphological changes related to extracellular matrix remodelling. To analyse whether the matrix metalloproteinases (MMPs), particularly MMP-2, MMP-9, and the tissue inhibitor of metalloproteinases-2 (TIMP-2), are associated with morphological alterations found in placentas, the expression of these enzymes was evaluated by immunohistochemical and image analyses in placentas of women with histories of environmental exposure to Pb. The median maternal concentration of Pb in blood was 4.68 µg/dL ([Formula: see text] = 5.85 ± 6.48 µg/dL). Significant differences related to the exposure to Pb were not detected in newborn or placenta weight. MMP-2, MMP-9, and TIMP-2 were expressed in the syncytiotrophoblast layer of placental villi. A significant increase in both MMP-2 and MMP-9 was observed in placentas of women with concentrations of Pb in blood ≥4.68 µg/dL ( p = 0.01 and 0.03 for MMP-2 and MMP-9, respectively)...
Inorganic arsenic (iAs) exposure induces a decrease in glucose type 4 transporter (GLUT4) express... more Inorganic arsenic (iAs) exposure induces a decrease in glucose type 4 transporter (GLUT4) expression on the adipocyte membrane, which may be related to premature births and low birth weight infants in women exposed to iAs at reproductive age. The aim of this study was to analyze the effect of sodium arsenite (NaAsO2) exposure on GLUT1, GLUT3, and GLUT4 protein expression and on placental morphology. Female Balb/c mice (n=15) were exposed to 0, 12, and 20 ppm of NaAsO2in drinking water from 8th to 18th day of gestation. Morphological changes and GLUT1, GLUT3, and GLUT4 expression were evaluated in placentas by immunohistochemical and image analysis and correlated with iAs and arsenical species concentration, which were quantified by atomic absorption spectroscopy. NaAsO2exposure induced a significant decrease in fetal and placental weight (P<0.01) and increases in infarctions and vascular congestion. Whereas GLUT1 expression was unchanged in placentas from exposed group, GLUT3 exp...
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