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Among the citrus production industry, Mexico represents the fifth largest producer worldwide as of 1 Mar 2022 data (Producción de cítricos en México, Biblioteca de Publicaciones Oficiales del Gobierno de la República, Gobierno, www.gob.mx [last accessed 3 Jun 2022]). Among insect pests affecting citrus orchards, the citrus blackfly Aleurocanthus woglumi Ashby (Hemiptera: Aleyrodidae) causes great economic losses to this industry. Biological control with parasitoids is used principally to manage this pest. In this study, we evaluated a simple and inexpensive technique for citrus blackfly biocontrol in citrus orchards. Conidia from the entomopathogenic fungus Aschersonia sp. were collected from citrus leaves with Aschersonia sp. infecting citrus blackfly nymphs in 1 locality in Quintana Roo State, Mexico. Conidia were suspended with vigorous shaking in a 0.1% Tween solution to achieve a concentration of about 1.0 × 108 conidia per mL and sprayed on citrus blackfly uninfected nymphs in 1 selected (high citrus blackfly population) Quintana Roo locality when relative humidity was about 95%. After about 55 d, fungus had killed the treated nymphs, and had infected and killed other citrus blackflies causing an epizootic in the application area. This technique was scaled up by citrus producers to 30 ha with similar results. During 2019, relative humidity was lower than 60%, and citrus blackfly-uninfected or Aschersonia sp.-infected nymphs were not detected. During 2020, the relative humidity was higher than 80% and we did not detect Aschersonia sp. Infected- or uninfected-citrus blackfly nymphs in the previously treated area. In conclusion, collection and application of Aschersonia sp. conidia on uninfected citrus blackfly nymphs may result in an epizootic, if relative humidity is 80% or higher, and Aschersonia sp. remains and disseminates along with this insect pest. Entre la industria de producción de cítricos, México representa el quinto productor a nivel mundial según datos del 01 de marzo del 2022 (Producción de cítricos en México, Biblioteca de Publicaciones Oficiales del Gobierno de la República, Gobierno, www.gob.mx [último accedido 3 Jun 2022]). Entre las plagas de insectos, la mosca prieta de los cítricos, Aleurocanthus woglumi Ashby (Hemiptera: Aleyrodidae) puede provocar grandes pérdidas económicas a esta industria. El control biológico con parasitoides es el método más utilizado para controlar esta plaga. En este estudio, evaluamos una técnica sencilla y económica en huertos de cítricos para el control biológico de la mosca prieta de los cítricos. Se recolectaron conidios del hongo entomopatógeno Aschersonia sp. de hojas de cítricos con Aschersonia sp. infectando ninfas de mosca prieta de los cítricos, en una localidad del estado de Quintana Roo. Los conidios se suspendieron con agitación vigorosa en una solución de Tween al 0.1% para lograr sobre 1.0 × 108 conidios por mL y se aplicaron mediante aspersión sobre ninfas no infectadas con mosca prieta de los cítricos, en una localidad seleccionada de Quintana Roo (alta población de mosca prieta de los cítricos), cuando la humedad relativa era sobre el 95%. Después de 55 días, el hongo ya habían matado a las ninfas tratadas e infectado y matado a otras mosca prieta de los cítricos, causando una epizootia en el área de aplicación. Se escaló esta técnica por los productores de cítricos en 30 hectáreas, lo que resultó en un biocontrol similar. Durante 2019, la humedad relativa fue inferior al 60% y la mosca prieta de los cítricos y no se detectaron ninfas sin infectar o infectadas por Aschersonia sp. Para 2020, la humedad relativa fue superior al 80% y se detectaron tanto la mosca prieta de los cítricos como ninfas infectadas por Aschersonia sp. en la zona previamente tratada. En conclusión, la recolección y aplicación de conidios de Aschersonia sp. sobre ninfas de mosca prieta de los cítricos no infectadas, podrían provocar una epizootia si la humedad relativa es del 80% o mayor y Aschersonia sp. podría permanecer y diseminarse entre esta plaga de insectos. [ABSTRACT FROM AUTHOR]

Studies on Hirsutella citriformis Speare are scarce. Among these, some reports have focused on phenotypic identification, based on its morphological structure and morphometric characteristics. This fungus is known to control economically important citrus crop pests. In recent years, H. citriformis has received increased attention as a control agent for the Asian citrus psyllid Diaphorina citri Kuwayama (Hemiptera: Liviidae), which causes the Huanglongbing (HLB) disease. Unfortunately, formal H. citriformis strains characterization is marginal, which mainly involves the role of biologically active exudates (metabolites) produced during their growth. Information regarding their mode of action and biocontrol potential is limited. However, epizootics reports of this fungus, under suitable environmental conditions for its development (25 °C to 28 °C and ~80% relative humidity), have demonstrated its parasitization efficacy. Therefore, it becomes challenging to determine whether H. citriformis strains may be developed as commercial products. In this review, we showed relevant information on isolation and bioassay strategies of H. citriformis to evaluate potential biocontrol strains under laboratory and field conditions in America. [ABSTRACT FROM AUTHOR]

Background: There is an increasing interest in using physical factors such as magnetic fields as antimicrobial strategy, with variable results. The current study was aimed to evaluate the influence of extremely low-frequency electromagnetic fields (ELF-EMFs) on the axenically-cultured parasite protozoans Trichomonas vaginalis and Giardia lamblia growth. Methods: Bioassays were developed using T. vaginalis, GT-13 and G. lamblia IMSS-0989 strains cultured at 37 ºC in TYI-S-33 medium. The following treatment regimens and controls were considered: (a) cells exposed to ELF-EMFs, (b) untreated cells, (c) cells treated with Metronidazole, used as positive controls, and (d) cells co-exposed to ELF-EMFs and Metronidazole. When cultures reached the end of logarithmic phase, they were exposed to ELF-EMFs for 72 h, in a standardized magnetic field exposure facility. For determining cytotoxic effects, trophozoite density was blindly evaluated in a Neubauer chamber. Results: A significant decrease in trophozoite growth was observed for T. vaginalis, in magnetic field-treated cultures. On the other hand, cultures co-exposed to ELF-EMFs and Metronidazole showed no significant differences when compared with cultures treated with Metronidazole alone. On the contrary, an increased trophozoite density was observed in G. lamblia cultures after exposure to magnetic fields. An absence of a synergistic or antagonistic effect was observed. Conclusion: ELF-EMFs induced T. vaginalis and G. lamblia growth alterations, indicating a potential effect in cell cycle progression. [ABSTRACT FROM AUTHOR]

Helicobacter pylori is an infectious agent that colonizes the gastric mucosa of half of the population worldwide. This bacterium has been recognized as belonging to group 1 carcinogen by the World Health Organization for the role in development of gastritis, peptic ulcers, and cancer. Due to the increase in resistance to antibiotics used in the anti-H. pylori therapy, the development of an effective vaccine is an alternative of great interest, which remains a challenge. Therefore, a rational, strategic, and efficient vaccine design against H. pylori is necessary where the use of the most current bioinformatics tools could help achieve it. In this study, immunoinformatics approach was used to design a novel multiepitope oral vaccine against H. pylori. Our multiepitope vaccine is composed of cholera toxin subunit B (CTB) that is used as a mucosal adjuvant to enhance vaccine immunogenicity for oral immunization. CTB fused to 11 epitopes predicted of pathogenic (UreB170–189, VacA459–478, CagA1103–1122, GGT106–126, NapA30–44, and OipA211–230) and colonization (HpaA33–52, FlaA487–506, FecA437–456, BabA129–149, and SabA540–559) proteins from H. pylori. CKS9 peptide (CKSTHPLSC) targets epithelial microfold cells to enhance vaccine uptake from the gut barrier. All sequences were joined to each other by proper linkers. The vaccine was modeled and validated to achieve a high-quality three-dimensional structure. The vaccine design was evaluated as nonallergenic, antigenic, soluble, and with an appropriate molecular weight and isoelectric point. Our results suggest that our newly designed vaccine could serve as a promising anti-H. pylori vaccine candidate. [ABSTRACT FROM AUTHOR]

Diseases are of particular importance for aquaculture worldwide, particularly in intensive culture. In Mexico, intensive culture of channel catfish is mainly done in floating cages. The aim of the present study was to determine the presence of the myxozoan Henneguya and the effect of site, period and host length on its prevalence in cage-cultured channel catfish. Over a year, fish were examined on six different sites. Results showed the presence of Henneguya exilis in all the farms. However, no significant effects were observed for site and season on prevalence, nor was there a correlation between host length and infection prevalence [ABSTRACT FROM AUTHOR]

The article focuses on the first records of ergasilus cerastes cage-reared icalurus from northeast Mexico. Ergasilus cerastes were recorded for the first time from District of Columbia where it was collected from a catfish sold at the Maine Avenue fish market. Ergasilus cerastes was now obtained from the gills of Ictalurus punctatus, which was cage-reared in five dams-lakes and a river in the state of Tamaulipas.

In the present study, we report the detection of immunogenic fetuin-A on L5178Y-R (LY-R) lymphoma cells. Fetuin-A was recognized by antibodies present in the serum of LY-R tumor-bearing and immunized mice, but not by sera of mice immunized with the non-tumorigenic variant LY-S or by healthy mouse sera. However, according with Western blot analysis with commercial anti-fetuin antibodies, fetuin-A is present in both cell types which suggests that the fetuin recognized by anti-LY-R antibodies is an immunogenic form associated only with the tumorigenic LY-R cells and might be involved in tumor progression in this lymphoma. [ABSTRACT FROM AUTHOR]

Morphine causes immunosuppression by binding to opioid receptors on immune cells, or indirectly by acting on receptors in the brain. However, morphine exact mechanism of action has not been elucidated. In the present study, we investigated the role of glucocorticoids in morphine-mediated immunosuppression after acute action in the rat mesencephalon periaqueductal gray (PAG). Natural killer (NK) cell activity and T cell proliferation were used to evaluate potential indirect mechanisms of morphine action. Microinjection of morphine in the ventral-caudal aspect of the PAG significantly (p < 0.01) suppressed splenic NK cell cytotoxic activity (32% reduction), and antiTCR-, IL-2-, antiTCR + IL-2, and Con A-induced thymic (30% to 50% reduction) and splenic (35% to 70% reduction) lymphocyte proliferation compared with PAG-injected saline control animals. The glucocorticoid receptor antagonist mifepristone (RU 486) did not block the immunosuppressive effects of morphine, suggesting that such effects are independent of activation of the hypothalamic-pituitary-adrenal axis. [Copyright &y& Elsevier]

Aedes aegypti (Linn.) incidence has increased in recent years, causing human viral diseases such as dengue, which are often fatal. Beauveria bassiana (Bals., Vuillemin) efficacy for Ae. aegypti biological control has been evidenced but it relies on host susceptibility and strain virulence. We hypothesized that B. bassiana conidia microgranular formulations (MGF) with the additives acetone, lactic acid, and sugar increase Ae. aegypti adult exposure, thus improving their biocontrol effectiveness. Beauveria bassiana strain four (BBPTG4) conidia stability was assessed after 0 d, 5 d, and 30 d storage at 25 °C ± 2 °C with additives or in MGF after 91 d of storage at 25 °C ± 2 °C or 4 °C ± 1 °C, whereas mortality was evaluated after adult exposure to MGF + conidia, using home-made traps. Additives did not show toxicity to conidia. In addition, we observed that sugar in MGF increased Ae. aegypti adults' attraction and their viability resulted in a 3-fold reduction after 5 d and 1- to 4-fold decrease after 30 d of storage, and formulations were less attractive (p < 0.05). Conidia stability was higher on MGF regardless of the storage temperature, losing up to 2.5-fold viability after 91 d. In conclusion, BBPTG4 infected and killed Ae. aegypti, whereas MGF attracting adults resulted in 42.2% mortality, increasing fungus auto dissemination potential among infected surviving adults. It is necessary to further evaluate MGF against Ae. aegypti in the field. [ABSTRACT FROM AUTHOR]

Rotavirus is the main cause of acute diarrhea in children up to five years of age. In this regard, probiotics are commonly used to treat or prevent gastroenteritis including viral infections. The anti-rotavirus effect of Bifidobacterium longum and Chlorella sorokiniana, by reducing viral infectivity and improving IFN-type I response, has been previously reported. The present study aimed to study the effect of B. longum and/or C. sorokiniana on modulating the antiviral cellular immune response mediated by IFN-γ, IL-10, SOCS3, STAT1, and STAT2 genes in rotavirus-infected cells. To determine the mRNA relative expression of these genes, HT-29 cells were treated with B. longum and C. sorokiniana alone or in combination, followed by rotavirus infection. In addition, infected cells were treated with B. longum and/or C. sorokiniana. Cellular RNA was purified, used for cDNA synthesis, and amplified by qPCR. Our results demonstrated that the combination of B. longum and C. sorokiniana stimulates the antiviral cellular immune response by upregulating IFN-γ and may block pro-inflammatory cytokines by upregulating IL-10 and SOCS3. The results of our study indicated that B. longum, C. sorokiniana, or their combination improve antiviral cellular immune response and might modulate pro-inflammatory responses. [ABSTRACT FROM AUTHOR]

Beauveria bassiana (Bals.) Vuillemin (B. bassiana) is an entomopathogenic fungus that establishes endophytic symbiosis with plants. In the present study, the effects of B. bassiana strains colonization in growing Zea mays L. (Z. mays), crop production, and drought tolerance were evaluated. Z. mays seeds were inoculated with B. bassiana strains (GHA, PTG4, and PTG6), using 1 × 106 blastospores/mL and methyl cellulose (MC) or cornstarch (CS) as adherents. Colonization was determined by B. bassiana recovery from plant tissues plated on PDA medium. Plant height, fresh and dry weight, and flowering time were analyzed to assess plant performance. Drought tolerance was evaluated by stopping watering for 10 days, watering again, and determining vigor recovery after 24 h. Results showed 100% endophytic roots colonization, regardless of adherent type or strain tested. Colonization was variable in shoots and leaves, but GHA strain achieved the highest inoculation rates, including 88% in stems and 50% in leaves, which did not depend on adherent type used; for PTG4 strain, adherent type had an important effect (MC = 100% stems and leaves; CS = 63% stems and 25% leaves). For PTG6 strain, the best adherent type was CS (71% stems and 75% leaves), whereas MC showed variable inoculation percentage (25% stems and 75% leaves). Interestingly, only MCPTG4 treatment showed consistent positive effects on germination percentage (day 5 = 46 ± 2%; day 14 = 87 ± 7%) compared with controls (CC = 63 ± 4%, CMC = 50 ± 3%, CCS = 47 ± 0%). In addition, the other treatments showed low germination percentages at day 5 (7 ± 7% to 46 ± 2%), which recovered at day 14 (53 ± 0% to 73 ± 8%), except for MCPTG6 treatment with 23 ± 10% germination. About plant performance, not significant effects on plant height and fresh/dry weight in all the treatments were observed. However, B. bassiana-treated plants, using either GHA, PTG4 or PTG6 strains, and MC as adherent, showed tolerance to drought and flowered one to two weeks earlier, providing evidence supporting further applications of these seed treatments in agricultural systems, for abiotic stress sustainable management practices. [ABSTRACT FROM AUTHOR]

The presence of Helicobacter pylori in the oral cavity has been associated to the failure of antimicrobial therapy in patients with gastrointestinal infection and the development of oral diseases. However, it has been reported that the maintenance of good oral hygiene can improve the therapeutic success rates, where the use of mouthwashes with anti-Helicobacter activity would help to achieve it. The aim was to evaluate the antimicrobial activity of OxOral® mouthwash against H. pylori and its effect on biofilm formation. The minimum inhibitory concentration (MIC) of OxOral® (pH = 6.4–7.5, ORP = 650–900 mV) against H. pylori was calculated testing serial dilutions 0.117–15 ppm against 1 × 108 CFU/mL of H. pylori (ATCC® 700824™) by broth microdilution method using 96‐well plates. The H. pylori biofilm formation was determined by the optical density measurement at 600 nm from coverslips stained with 0.1% crystal violet. The gene expression of ureA, luxS, flaA, omp18, and lpxD were analyzed by RT‐qPCR. OxOral® cytotoxicity was evaluated in a human gingival fibroblast cell line by MTT assay. MIC was of 3.75 ppm, with 99.7 ± 7.7% bacterial growth inhibition. In the negative control, the biofilm formation was observed, whereas when bacteria were treated with OxOral® at 0.234, 0.469, and 0.938 ppm, an inhibition of 35.5 ± 0.9%, 89.1 ± 1.2%, and 99.9 ± 5.5% were obtained, respectively. The gene expression analysis showed that flaA, omp18, and lpxD genes were down‐regulated with OxOral® compared with control (p < 0.05). Low cytotoxicity of 16.5 ± 7.6% was observed at the highest dose (15 ppm); no significant differences were observed from 15 to 0.469 ppm compared to the control of untreated cells (p > 0.05). Our results reveal an important anti-Helicobacter activity of OxOral® and open the possibility of its therapeutic use new studies, which would increase the success rate of conventional therapies against H. pylori. [ABSTRACT FROM AUTHOR]

The influence of extremely low-frequency electromagnetic fields (ELF-EMFs) on microorganisms has been a subject of experimental investigations with promising results. In the present study, it was demonstrated that 2.0 mT 60Hz ELF-EMFs inhibited Trypanosoma cruzi epimastigotes growth. In addition, no synergistic or antagonistic parasite growth and viability effects were observed after cultures were co-exposed to magnetic fields and Nifurtimox, a well-known anti-trypanosome drug. Moreover, the current study represents the first report regarding direct magnetic fields effects on Trypanosomas. [ABSTRACT FROM AUTHOR]

Helicobacter pylori is a spiral Gram-negative bacterium associated with inflammation of the gastric mucosa, peptic ulcer, and gastric adenocarcinoma, whose treatment has failed due to antibiotic resistance and side effects. Furthermore, because there are no vaccines effective against H. pylori, an appropriate vaccine design targeting conserved/essential genes must be identified. In the present study, a H. pylori 50–52 kDa immunogen-derived peptide antigen with the sequence Met-Val-Thr-Leu-Ile-Asn-Asn-Glu (MVTLINNE) was used to immunize against H. pylori infection. For this, mice received an intraperitoneal injection of 100 μg of H. pylori peptide on the first week, followed by two weekly subcutaneous reinforcements and further 109 bacteria administration in the drinking water for 3 weeks. Thymic cells proliferative responses to concanavalin A, serum levels of IL-2, IL-4, IL-6, IL-10, IL-17, IFN-γ, and TNF-α cytokines, and IgG1, IgG2a, IgG2b, IgG3 IgM, and IgA immunoglobulins were evaluated. Significant (p<0.05) increases on lymphoproliferation and spleen weights after immunization were observed. In contrast, infection significantly (p<0.05) decreased lymphoproliferation, which was recovered in immunized mice. In addition, levels of serum TH1 and TH2 cytokines were not altered after immunization, except for the significant increase in IL-6 production in immunized and/or infected animals. Moreover, immunization correlated with plasma secretory IgA and IgG, whereas infection alone only elicited IgM antibodies. Peptide immunization protected 100% of mice against virulent H. pylori. MVTLINNE peptide deserves further research as an approach to the prophylaxis of H. pylori infection. [ABSTRACT FROM AUTHOR]

Cancer is a major health problem with significant morbidity and mortality. In addition, plants are a source of metabolites with diverse biological properties, including antitumor potential. In this study, we investigated the in vitro murine lymphoma L5178Y-R cell growth inhibition, human peripheral blood mononuclear cells (PBMC) toxicity and proliferation, and antioxidant, hemolytic, and anti-hemolytic activities of methanol extracts from 15 plants of traditional use in Mexico. Justicia spicigera caused the highest tumor cell growth inhibition with a half maximal inhibitory concentration (IC50) of 29.10 µg/mL and a selectivity index >34.36 compared with those of PBMC, whereas Mimosa tenuiflora showed the highest lymphoproliferative activity from 200 µg/mL compared with that induced by concanavalin A. In addition, M. tenuiflora showed an antioxidant effect (IC50 = 2.86 µg/mL) higher than that of ascorbic acid. Regarding the hemolytic and anti-hemolytic activity, all extracts presented significant anti-hemolytic activity. The extract of J. spicigera is emerging as a possible source of effective antineoplastic compounds. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) produced by the neem tree (Azadirachta indica A. Juss.; Sapindales: Meliaceae) are known to alter growth and development of several insects. Additionally, the insect's gut microbiota and immune response are key components in insect development and have been linked to increased resistance to insecticides. In the present study, larval mortality, immune response, and intestinal bacteria changes in the cabbage looper, Trichoplusia ni (Hübner) (Lepidoptera: Noctuidae), induced by VOCs of dried and milled neem leaves, stems, and bark were investigated. Exposure of neonates to 10 g of mixed dried leaves and stems resulted in 79 and 63% mortality of laboratory and field T. ni strains, respectively. In addition, differences were observed in larval weights and pupal sizes during 30 d of incubation. Further studies included transcript amplification of enterobacteria genes and genes related to immune responses and chemical synthetic insecticide resistance. Midguts from the VOC-exposed laboratory strain of T. ni larvae over-transcribed cytochrome P450 (CYP4L4), PGRP, lysozyme, attacin, cecropin, defensin, gallerimycin, and lebocin, compared with unexposed control larvae, whereas ribosomal protein S5 (internal control) and caspase transcripts did not show changes. These samples revealed reduced enterobacteria transcript amplification (27%), suggesting bacterial repression. The effect of neem VOCs on the immune response may in part explain the inhibitory effect on the molting process, in which chitin is broken down to release the old cuticle between instars. Because neem leaves, stems, and bark are widely used as fertilizers, their potential application in pest management programs for controlling T. ni on host crops (cauliflower, broccoli, or cabbage) is discussed. [ABSTRACT FROM AUTHOR]

Objective. To evaluate the effect of the combination of calcium hydroxide (Ca(OH)2) and a novel electrolyzed superoxidized solution at neutral pH, known as OxOral® on Enterococcus faecalis growth in root canals. Methods. Sixty human teeth were used, from which root canals were infected and randomly divided into the following treatment groups: saline solution, saline solution plus Ca(OH)2, OxOral®, and OxOral® plus Ca(OH)2. Results. A permanent reduction in bacterial growth was observed at days 1, 6, 12, and 18 after OxOral® plus Ca(OH)2 treatment from 4.4 ± 0.074 log 10 CFU / mL to 0.0 ± 0.001 log 10 CFU / mL. In addition, alkaline conditions maintenance was observed from application time (pH = 12.2 ± 0.033) to 18 d posttreatment (pH = 12.6 ± 0.083). Conclusion. The combination of OxOral® and Ca(OH)2 provides an alkaline pH and inhibits E. faecalis growth into the root canals. Our study opens the possibility for further research on the use of OxOral® in endodontic therapy. [ABSTRACT FROM AUTHOR]

Bioassay-guided fractionation of hexane extracts of Gymnosperma glutinosum (Asteraceae) leaves, collected in North Mexico, afforded the known compounds hentriacontane (1) and (+)-13S,14R,15-trihydroxy-ent-labd-7-ene (2), as well as the new ent-labdane diterpene (-)-13S,14R,15-trihydroxy-7-oxo-ent-labd-8(9)-ene (3). In addition, D-glycero-D-galactoheptitol (4) was isolated from the methanolic extract of this plant. Their structures were established on the basis of high-field 1D- and 2D NMR methods supported by HR-MS data. The cytotoxic activity was determined by using the in vitro L5178Y-R lymphoma murine model. Hentriacontane (1) and the new ent-labdane 3 showed weak cytotoxicity, whereas the ent-labdane 2 showed significant (p < 0.05) and concentration dependent cytotoxicity (up to 78%) against L5178Y-R cells at concentrations ranging from 7.8 to 250 μg/mL. [ABSTRACT FROM AUTHOR]

Annual mortality rates due to infectious diarrhea are about 2.2 million; children are the most vulnerable age group to severe gastroenteritis, representing group A rotaviruses as the main cause of disease. One of the main factors of rotavirus pathogenesis is the NSP4 protein, which has been characterized as a viral toxin involved in triggering several cellular responses leading to diarrhea. Furthermore, the rotavirus protein NSP1 has been associated with interferon production inhibition by inducing the degradation of interferon regulatory factors IRF3, IRF5, and IRF7. On the other hand, probiotics such as Bifidobacterium and Lactobacillus species in combination with prebiotics such as inulin, HMO, scGOS, lcFOS have been associated with improved generalized antiviral response and anti-rotavirus effect by the reduction of rotavirus infectivity and viral shedding, decreased expression of NSP4 and increased levels of specific anti-rotavirus IgAs. Moreover, these probiotics and prebiotics have been related to shorter duration and severity of rotavirus diarrhea, to the prevention of infection and reduced incidence of reinfections. In this review we will discuss in detail about the rotavirus pathogenesis and immunity, and how probiotics such as Lactobacillus and Bifidobacterium species in combination with prebiotics have been associated with the prevention or modulation of rotavirus severe gastroenteritis. [ABSTRACT FROM AUTHOR]

Plodia interpunctella (Hübner) is an important stored grain insect pest worldwide, and the first lepidopteran with reported resistance to Bacillus thuringiensis ( Bt ) toxins. Since gut bacteria may affect Bt insecticidal activity, we evaluated whether P. interpunctella lacking gut bacteria had differences in immune responses and susceptibility to the Bt formulation, Bactospeine. In order to clear gut bacteria, third instar larvae were reared on artificial diet containing antibiotics, or were obtained from sterilized eggs and reared under sterile conditions, and larvae were fed diets with or without Bt. Mortality was significantly lower ( p < 0.05) in bacteria-free larvae treated with Bt, compared with Bt -treated larvae with unaffected gut bacteria. The number of hemocytes was lower in control and Bt -treated larvae, but was significantly higher ( p < 0.001) in larvae treated with antibiotics and Bt , and larvae from presterilized eggs and reared on sterile diet had the highest number of hemocytes. Phenoloxidase activity was significantly lower ( p < 0.05) in Bt-treated larvae from presterilized eggs reared on antibiotics for 24 h or in larvae reared on antibiotic-treated diets prior to Bt introduction compared with those fed control diet. Hemolin gene expression was reduced in larvae fed Bt diets compared with control and was not detected in larvae treated with antibiotics. Larvae from sterilized eggs and fed sterile diet never reached the pupal stage. Therefore, the loss of gut bacteria in P. interpunctella larvae affected the host immune response and expression of the hemolin gene, and significantly reduced susceptibility to Bt . [ABSTRACT FROM AUTHOR]

The Mexican bean beetle, Epilachna varivestis Mulsant, is an important pest of bean ( Phaseolus vulgaris L.) crops in Mexico and eastern United States. The Beauveria bassiana isolates TM0307 and SyDBbh5001M require large amounts to be effective in the field. Liquid culture medium containing cotton ( Gossypium hirsutum L.) flour was evaluated to improve their virulence against E. varivestes. Virulence of B. bassiana blastospores was evaluated using various culture media and Sabouraud dextrose broth as a control, testing potential of cotton flour versus peptone as a nitrogen source, and colloidal chitin and Lepidoptera exuvia as sources of chitin. Samples were collected every 24 hours, and production of cuticle-degrading proteases (Pr1 and Pr2) and chitinase (NAGase) was determined during 5 days. The lowest enzyme production was observed in Sabouraud dextrose broth and colloidal chitin cultures, whereas the highest production was observed in chitin with cotton flour (Pr1 = 23.2, 2.3, and 126.2 U/ml; Pr2 = 12.7, 2.3, and 48.7 U/ml; NAGase = 5.4, 0.6, and 9.1 U/ml in Sabouraud dextrose broth, colloidal chitin, and chitin with cotton flour cultures, respectively). The LC50 in chitin with cotton flour versus Sabouraud dextrose broth media was evaluated by testing six doses against E. varivestis third-instar larvae; median survival time (ST50) was measured by testing 1 × 108 blastospores per milliliter. Significant lower LC50 and ST50 values were observed by blastospores produced in chitin with cotton flour medium (2.1 ± 1.7 to 2.8 × 106 blastospores per milliliter and 2 days), compared with those on Sabouraud dextrose broth (9.8 ± 6.3 to 15.9 × 106 blastospores per milliliter and 4 days), respectively. Results indicated potential of cotton flour to increase virulence of B. bassiana blastospores against E. varivestis third-instar larvae by enhancing production of insect cuticle-degrading enzymes. [ABSTRACT FROM AUTHOR]

Biological control of Bactericera cockerelli using a combination of parasitoids and pathogens has potential. However, their combined use could result in complex multitrophic interactions, the outcomes of which are uncertain. In this study we evaluated the effects of applications of two Beauveria bassiana isolates (pathogen) on the parasitoid Tamarixia triozae during its development on the host, B. cockerelli . Three concentrations (LC 20 , LC 50 and LC 90 values against B. cockerelli ) of the fungal isolates BB40 and GHA were applied to 4th instar B. cockerelli nymphs that had been successfully parasitized by T. triozae 3, 5, 8 or 12 days earlier at 25 °C. The greatest infection of T. triozae was observed when the calculated LC 90 was inoculated, regardless of isolate, and when the parasitoids were 3–5 days old. The lowest infection of T. triozae was observed when they were 8 and 12 days old regardless of isolate or conidial concentration. The highest parasitoid emergence was achieved in the untreated control compared with all other treatments and combinations tested. Within treatments, the highest parasitoid emergence was obtained at the lowest B. bassiana concentration tested and when the pathogen was applied to B. cockerelli supporting 12 day-old parasitoids. Longevity of adult parasitoids that had emerged from B. cockerelli nymphs was greatest in the control treatment, followed by those from nymphs treated with GHA when applied to B. cockerelli supporting 12 day-old parasitoids. In conclusion, biological control of B. cockerelli may require the synchronized use of high B. bassiana concentrations, applied only on T. triozae late pupal stage (8–12 days of development), in order to allow the parasitoid to survive and also achieve good overall pest control. [ABSTRACT FROM AUTHOR]

Bactericera cockerelli (Sulc.) is an important pest of solanaceous crops and a vector of the pathogen Candidatus Liberibacter psyllaurous . Biocontrol of this pest has been attempted with either entomopathogenic fungi or the parasitoid Tamarixia triozae (Burks), but prior to this study, their potential impact in combination had not been studied. The aim of the present study was to evaluate T. triozae parasitism rates on B. cockerelli nymphs that were previously infected for different periods of time by three isolates of Beauveria bassiana (Bals.) Vuill. Two native isolates (BB40 and BB42) and one commercial isolate (GHA) were used. The virulence of these isolates was first estimated against B. cockerelli and T. triozae . LC 50 values for the native isolates BB40 and BB42 against B. cockerelli were 9.5 × 10 5 and 2.42 × 10 6 conidia mL −1 respectively; they were significantly more virulent than isolate GHA with an LC 50 of 1.97 × 10 7 conidia mL −1 . However, isolate GHA was significantly more virulent against T. triozae with an LC 50 of 1.11 × 10 7 conidia mL −1 compared with LC 50 s of 1.49 × 10 7 and 1.14 × 10 8 conidia mL −1 for the native isolates BB40 and BB42 respectively. Groups of nymphs were then inoculated with LC 20 , LC 50 or LC 90 concentrations of each isolate and presented to T. triozae as hosts either on the day of inoculation or 1, 2, 3, 4, 5, 6 days after inoculation. Subsequent levels of parasitism were recorded. Overall, parasitism rates were similar in inoculated and control nymphs. No parasitism occurred in nymphs 6 days after fungal inoculation. Parasitoids used to parasitize uninoculated B. cockerelli nymphs survived significantly longer (7.8 days) than parasitoids that had been used to parasitize fungus-inoculated nymphs (7.3 days). This suggests an inability of the parasitoid to avoid infection when foraging on inoculated nymphs. In conclusion, although the parasitism rate in control and fungus-treated nymphs was similar, suggesting a combination of both biological control agents is possible, we believe there are also negative implications for the parasitoid because its survival was greatly reduced after attacking infected nymphs. [ABSTRACT FROM AUTHOR]

Background American trypanosomiasis is a major disease and public health issue, caused by the protozoan parasite Trypanosoma cruzi. The prevalence of T. cruzi has not been fully documented, and there are few reports of this issue in Nuevo Leon. The aim of this study was to update the seroprevalence rate of T. cruzi infection, including an epidemiological analysis of the risk factors associated with this infection and an electrocardiographic (ECG) evaluation of those infected. Methods Sera from 2,688 individuals from 10 municipalities in the state of Nuevo Leon, Mexico, were evaluated using an enzyme-linked immunosorbent assay and an indirect hemagglutination assay. An ECG case–control study was performed in subjects seropositive for T. cruzi and the results were matched by sex and age to seronegative residents of the same localities. A univariate analysis with χ2 and Fisher’s exact tests was used to determine the association between seropositivity and age (years), sex, and ECG changes. A multivariate analysis was then performed to calculate the odd ratios between T. cruzi seropositivity and the risk factors. Results The seropositive rate was 1.93% (52/2,688). In the ECG study, 22.85% (8/35) of the infected individuals exhibited ECG abnormalities. Triatoma gerstaeckeri was the only vector reported. The main risk factors were ceiling construction material (P ≤ 0.0024), domestic animals (P ≤ 0.0001), and living in rural municipalities (P ≤ 0.0025). Conclusions These findings demonstrate a 10-fold higher prevalence of Chagas disease than previously reported (0.2%), which implies a serious public health threat in northeastern Mexico. The epidemiological profile established in this study differs from that found in the rest of Mexico, where human populations live in close proximity to domiciliary triatomines. where human populations live in close proximity to domiciliary triatomines. [ABSTRACT FROM AUTHOR]

Abstract: Opioids represent a major source of relief for acute and chronic, moderate to severe nonmalignant pain. However, opioid abuse may cause immunosuppression leading to infections and cancer development. Recently we reported results on novel non-peptidic delta- and mu-selective opioids that induced immunopotentiation in vitro and ex vivo. In the present study, we investigated the effects of the delta agonist SNC 80, and mu agonists, naltrindole and naltrexone derivatives for their capacity to alter lymphoproliferation in vitro. They were observed to stimulate lymphoproliferation at concentrations ranging from 10−10 to 10−5 M. SNC 80 significantly (p &#60;0.05) stimulated (43–311%) proliferation of resident and concanavalin A (Con A)-treated lymphocytes; the naltrindole derivatives 9332 and 9333 caused significant (p &#60;0.05) 26–47% and 13–43%, respectively, stimulation of Con A-treated lymphoproliferation; whereas the naltrexone derivatives 9334 and 9336 significantly (p &#60;0.05) stimulated 9–40% and 15–69%, respectively, proliferation of resident and Con A-treated lymphocytes. These novel opioid ligands could serve as immunotherapeutic agents by increasing the pool of lymphocytes with potential use in the treatment of infectious diseases including AIDS. This study provides evidence of the relationship structure/function of opioids on lymphoproliferation, and supports further evaluation of opioids with immunomodulatory potential in preclinical and clinical studies. [Copyright &y& Elsevier]

Bacillus thuringiensis strains C-4, C-9, GM-7, and GM-10, isolated from northeast Mexico and selected for their high toxicity against lepidopteran and coleopteran pests, were characterized following United States Environmental Protection Agency (EPA)’s guidelines. Flagellar serotyping revealed that GM-7 and GM-10 belonged to serotype aizawai, whereas C-4, C-9 corresponded to the kumamotoensis serotype. GM-10 and C-9 were also shown to be the most effective against lepidoptera and coleoptera larvae, respectively. None of the tested strains produced β-exotoxin or showed activity against mosquitoes. GM-7 and GM-10 were sensitive to R-41 and CP-51 phages. All strains synthesized crystal proteins of 130–140 kDa. PCR analysis showed that C-4, GM-7, and GM-10 strains expressed cry1 genes, and C-9 expressed cry3 and cry7/8 genes, but not cry1. However, the C-9 strain had no cross-reaction with antisera raised against Cry3A and Cry7A proteins. GM-7 and GM-10 were sensitive to R-41 and CP-51 phages. When the δ-endotoxin (crystal) from the four strains was subcutaneously injected to Balb/c mice, alone or in combination with spores, only C-4 and C-9 provoked tissue necrosis similar to that caused by the β-exotoxin producer HD-41. Tissue necrosis was prevented with the injection of pentoxifylline, an inhibitor of tumor necrosis factor α (TNF-α) production, suggesting a role of this cytokine in the observed effect. Our results demonstrated that GM-7 and GM-10 strains are effective and suitable for control of lepidopteran pests and safe for mammals under EPA regulations. The potential of the C-9 strain for the control of several coleopteran pests, and the induction of tissue necrosis in mice by C-4 and C-9 strains, are discussed. [Copyright &y& Elsevier]

Indoloquinolizines are natural alkaloid indole products grouped as β-carbolines. These compounds are commonly associated with neurological activities, but little is known about their role as immunomodulating agents. The present study was undertaken to evaluate the effects of synthetic indoloquinolizines on in vitro parameters of rat lymphocyte and macrophage functions. It was observed that proliferation of thymic lymphocytes was significantly (p<0.05) increased (20–30% increase) by dihydro-indoloquinolizinium chloride (2), dihydro-indoloquinolizinyl-ethanone (3), and dimeric dihydro-indoloquinolizinium dichloride (6), whereas dimeric indoloquinolizine (7) caused up to 40% increase in lymphoproliferation at concentrations ranging from 10−11 to 10−5 M, compared with untreated control. In contrast, indoloquinolizinium chloride (4) and indoloquinolizine (5) were toxic for lymphocytes at concentrations from 10−9 to 10−5 M, and compounds 6 and 7 were toxic at 10−5 M. In addition, nitric oxide production by LPS-treated peritoneal macrophages was significantly (p<0.05) increased (up to 30% increase) by compounds 4 and 5 at concentrations of 10−11 to 10−5 M, and 10−5 M, respectively; however, compounds 6 and 7 were toxic for macrophages at all concentrations tested. Furthermore, TNF-α production was also significantly increased (p<0.01) by compounds 4 and 5 (up to 30-fold increase) compared with untreated control. These novel synthetic indoloquinolizines could serve as immunotherapeutic agents by selectively increasing the pool of activated T lymphocytes or stimulating macrophage functions, with potential use in the treatment of infectious diseases including AIDS and cancer. [Copyright &y& Elsevier]

• Quasi-spherical AgNPs/CMC composites inhibited in vitro growth of C. albicans , E. faecalis , and F. nucleatum. • AgNPs/CMC composites significantly reduced heterogeneous biofilm formation on dentin discs. • AgNPs/CMC composites are not toxic to normal cells and require shorter exposure time than conventional procedures. • The use of AgNPs/CMC composites is recommended as alternative irrigation agents in endodontic treatments. To evaluate the antimicrobial activity of a silver nanoparticles/carboxymethyl-cellulose (AgNPs/CMC) composite on in vitro and dentine disc heterogeneous biofilms. AgNPs/CMC composite effect on normal human gingival fibroblast cells (HGF) viability was determined by the MTT reduction assay. In addition, we evaluated the antimicrobial effect of AgNPs/CMC composite on Candida albicans , Enterococcus faecalis , and Fusobacterium nucleatum growth in vitro and heterogeneous biofilms, as well as dentine disc biofilms. Quasi -spherical AgNPs/CMC composites, with a mean 22.3 nm particle-size were synthesized. They were not toxic to HGF cells at concentrations tested that were antimicrobial, however they caused significant cytotoxicity (89 %, p < 0.05) at concentrations > 15 μg/mL. In vitro , they inhibited up to 67 %, 66 %, and 96 % C. albicans, E. faecalis , and F. nucleatum growth at concentrations ranging from 1.2 μg/mL to 9.6 μg/mL, as compared with untreated control. We also demonstrated significant (p < 0.05) 58 % biofilm reduction by 4.8 μg/mL AgNPs/CMC composite on human dentine discs. AgNPs/CMC composite showed anti biofilm activity on monocultures, heterogenous cultures, and dentine discs, resulting a potentially effective alternative to prevent and eliminate infections after endodontic treatment. [ABSTRACT FROM AUTHOR]

Contact with stinging spines venom from several Lepidoptera larvae may result in skin lesions. In Mexico, envenomation outbreaks caused by Megalopyge opercularis were reported between 2015 and 2016. The aim of this study was to identify the venomous caterpillars in Nuevo Leon, Mexico and evaluate several biological activities of their hemolymph (HEV) and spine setae (SSV) venoms. M. opercularis was identified by cytochrome oxidase subunit (COI) designed primers. HEV and SSV extracts cytotoxic activity was assessed on the L5178Y-R lymphoma cell line. For apoptotic cells number and apoptosis, cells were stained with acridine orange/ethidium bromide and validated by DNA fragmentation. Human peripheral blood mononuclear cells (hPBMC) cytokine response to the extracts was measured by the cytometric bead array assay. Extracts effect on pro-coagulation activity on human plasma was also evaluated. HEV and SSV extracts significantly inhibited (p < 0.01) up to 63% L5178Y-R tumor cell growth at 125–500 µg/mL, as compared with 43% of Vincristine. About 79% extracts-treated tumor cells death was caused by apoptosis. Extracts stimulated (p < 0.01) up to 60% proliferation of resident murine lymphocytes, upregulated IL-1β, IL-6, IL-8, and TNF-α production by hPBMC, and showed potent pro-coagulant effects. The pharmacological relevance of these venoms is discussed. [ABSTRACT FROM AUTHOR]

Human papilloma virus (HPV) is a DNA virus associated with the development of cervical, penile, anal, vulvar, and oral cancers. In recent years, there has been an increase in oral cancer, which could be due to changes in sexual behavior in the general population. In México, there is scarce information on this regard, which prompted us to study HPV infection prevalence in the oral cavity of an indigenous community from the municipality of Siltepec, Chiapas, Mexico. Oral samples from 198 individuals were obtained with cytobrush for virus detection by nested PCR, using MY09/MY11 and GP5+/GP6+ primers, and positive samples were sequenced for HPV genotyping. We observed 12.1% HPV infection prevalence, which depended on gender, number of sexual partners, lack of using condoms, and oral sex practices. In contrast, no significant association between HPV infection and tobacco or alcohol consumption was detected. Furthermore, sequencing analyzes were performed where HPV-13 (21/24), -16 (2/24), -32 (1/24), -81 (1/24), and -83 (1/24) were evidenced and HPV-16 European/Asian and Asian/American E6 variants identified. These results demonstrated an important prevalence of HPV infection in the oral cavity of a Mexican indigenous community, where the predominant genotypes were associated with benign pathologies, and showed that high-risk genotype variants derived from different lineages. Unlabelled Image • Prevalence of HPV infection in the oral cavity of a Mexican indigenous community • Predominant genotypes were associated with benign pathologies. • High-risk genotype variants derived from different lineages. [ABSTRACT FROM AUTHOR]

Background: American trypanosomiasis is a major disease and public health issue, caused by the protozoan parasite Trypanosoma cruzi. The prevalence of T. cruzi has not been fully documented, and there are few reports of this issue in Nuevo Leon. The aim of this study was to update the seroprevalence rate of T. cruzi infection, including an epidemiological analysis of the risk factors associated with this infection and an electrocardiographic (ECG) evaluation of those infected.Methods: Sera from 2,688 individuals from 10 municipalities in the state of Nuevo Leon, Mexico, were evaluated using an enzyme-linked immunosorbent assay and an indirect hemagglutination assay. An ECG case-control study was performed in subjects seropositive for T. cruzi and the results were matched by sex and age to seronegative residents of the same localities. A univariate analysis with χ2 and Fisher's exact tests was used to determine the association between seropositivity and age (years), sex, and ECG changes. A multivariate analysis was then performed to calculate the odd ratios between T. cruzi seropositivity and the risk factors.Results: The seropositive rate was 1.93% (52/2,688). In the ECG study, 22.85% (8/35) of the infected individuals exhibited ECG abnormalities. Triatoma gerstaeckeri was the only vector reported. The main risk factors were ceiling construction material (P ≤ 0.0024), domestic animals (P ≤ 0.0001), and living in rural municipalities (P ≤ 0.0025).Conclusions: These findings demonstrate a 10-fold higher prevalence of Chagas disease than previously reported (0.2%), which implies a serious public health threat in northeastern Mexico. The epidemiological profile established in this study differs from that found in the rest of Mexico, where human populations live in close proximity to domiciliary triatomines. [ABSTRACT FROM AUTHOR]