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Chagas disease, caused by the protozoan Trypanosoma cruzi, represents an important and worldwide public health issue, particularly in Latin America. Limitations of conventional treatment with benznidazole and nifurtimox underscore the urgent need for new therapeutic strategies for this disease. Schinus molle, a tree used in traditional medicine for various ailments, has demonstrated promising antiparasitic activity. The in vitro anti-T. cruzi activity of Schinus molle crude methanol extract, partitions, and fractions, as well as their cytotoxicity in Vero cells and Artemia salina, and hemolytic activity in human erythrocytes were assessed. Most of the extracts possessed anti-T. cruzi effects, with Sm-CF3 being the fraction with the highest activity (IC50 = 19 µg/mL; SI = 6.8). Gas chromatography–mass spectrometry analysis identified 20 compounds, with fatty acyls comprising the predominant chemical class (55%). We also identified the antiparasitic compounds cis-5,8,11,14,17-eicosapentaenoic acid and trans-Z-α-bisabolene epoxide, suggesting their potential contribution to the observed anti-T. cruzi activity. In conclusion, our findings support the therapeutic potential of S. molle as a source of novel antiparasitic agents against T. cruzi. [ABSTRACT FROM AUTHOR]

Beauveria bassiana has potential for Aedes aegypti biological control. However, its efficacy depends on the strain's geographic location, host susceptibility, and virulence. The present study aimed to evaluate the effectiveness of B. bassiana strain BBPTG4 conidia in controlling Ae. aegypti adults and its detection via introns profile on exposed mosquito corpses. Morphologic characteristics among strains were highly similar. Comprehensive testing of these strains demonstrated that BBPT4 exhibited the ideal biological activity for Ae. aegypti control, with a median lethal time (TL50) of 7.5 d compared to ~3 d and ~10 d for BB01 and BB37 strains, respectively. Infected mosquitoes died after GHA and BBPTG4 exposure, and corpses were analyzed for infecting strains detection. Differences among the seven evaluated strains were determined, assessing five different insertion group I intron profiles in BBTG4, BB01, GHA, BB37, and BB02 strains. Mosquitoes infected by BBPTG4 and non-exposed (negative control) intron profiles were obtained. We detected the presence of introns in the BBPTG4 strain, which were not present in non-exposed mosquitoes. In conclusion, B. bassiana strains showed similarities in terms of their cultural and microscopic morphological characteristics and biologicals virulence level, but different intron profiles. BBPTG4 strain-infected Ae. aegypti adult corpses, showing specific amplicons, enabled us to identify B. bassiana at the strain level among infected mosquitoes. However, monitoring and detection of field-infected insects is essential for further verification. [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 (B. bassiana) is a significant entomopathogenic fungus (EPF) in agriculture as a sprayable biocontrol agent. It has the potential to be established as an endophyte (ENP) in various crops, resulting in beneficial effects for the host plants, including resistance to pest insects and increased growth and yield. However, it is not known whether a B. bassiana strain has such a favorable impact on the plant, since it is a common soil microorganism. Therefore, techniques that allow strain monitoring will be advantageous. To date, methods for detecting or monitoring a specific EPF strain after external application are scarce. In the present study, an in planta nested PCR technique was standardized to differentiate between three B. bassiana strains (GHA, PTG4, and BB37) established as endophytes in bean plants under laboratory conditions by detecting the insertion profile of four group I introns located in the 28S gene of B. bassiana ribosomal DNA. This technique recognized a distinct pattern of bands of different sizes for each strain, with a sensitivity of 1 pg per 10 ng of plant DNA. This molecular approach may be more effective monitoring B. bassiana strains after application to evaluate their significance on crops. [ABSTRACT FROM AUTHOR]

Objective. Food insecurity (FI) is a priority for government and health organizations. Over 95% of the world's population has a carious lesion or will develop one before death. This study evaluated the association between FI and oral health in two rural communities in Chiapas, Mexico. Methods. The study was conducted with patients attending an oral health campaign for dental checkups. Data were collected between April and August 2017 using the Latin-American and Caribbean Scale of Food Security (ELCSA) and the International Caries Detection and Assessment System (ICDAS). We included 209 participants from Siltepec and Huehuetan, Mexico; 67% were women. Results. The results of the ELCSA were mild FI in 43% (n = 91), moderate FI in 22% (n = 45), and severe FI (n = 6) in 3%; 32% had food security. The ICDAS results were initial decay with a mean of 6.22, moderate decay with a mean of 1.81, and extensive decay with a mean of 1.77. Conclusions. FI is associated with dental caries, and food-insecure individuals have a higher probability of severe dental caries. In this study, the FI level was lower than in other rural populations in Mexico. Identifying these individuals and addressing the factors related to FI can be useful in the rural communities. [ABSTRACT FROM AUTHOR]

Hirsutella citriformis Speare is the only entomopathogenic fungus that has been applied to control the hemipteran Diaphorina citri Kuwayama. However, the use of available commercial products under field conditions is limited due to conidia's shelf life and short environmental persistence. We have previously reported the citrus psyllid D. citri adults' biocontrol potential using H. citriformis strains. The aim of the present study was to evaluate different formulations based on H. citriformis (OP-Hir-3, OP-Hir-10, and OP-Hir-12 strains) conidia and gums as additives to improve D. citri adults' biocontrol, under laboratory, greenhouse, and field conditions, using Hirsutella gums as conidia stabilizers to improve their viability under environmental drought conditions and as insecticide. Laboratory bioassay results showed that the highest (p < 0.05) D. citri mortality was achieved using FOP-Hir-10GH (63.5%), followed by the Hirsutella gum control (42.2%). Under greenhouse conditions, adults' mortality reached up to 84.6% with FOP-Hir-12 and 49.0% with Hirsutella gum. In addition, we applied H. citriformis formulations under field conditions in a commercial citrus grove located in Tecomán, Colima, México, at 21.5 °C and 73.3% relative humidity (RH) in March and 25.7 °C and 72.5% RH in October 2022 and observed 67.3% and 94.0% mortality of D. citri adults, respectively. Hirsutella gum alone showed significant insecticidal activity against D. citri adults. In conclusion, this study demonstrated that Hirsutella gum functioned as additive to H. citriformis conidia formulations, improving D. citri adults' mortality and showing potential for this pest biocontrol in citrus orchards. [ABSTRACT FROM AUTHOR]

Purpose: Epidemiological studies have been conducted to improve the health and economic quality of life of indigenous communities in Mexico. These studies have found that infections cause frequent health problems. Helicobacter pylori are responsible for conditions ranging from gastritis to stomach cancer. This study determined the prevalence of H. pylori in families from Siltepec, Chiapas, Mexico.Patient and Methods: Ninety-nine dental plaque samples from 36 families were studied. Real-time PCR was performed to detect H. pylori using previously reported primers. The Mann–Whitney U-test was used for the statistical analysis. According to the family role of H. pylori-positive individuals, the VacA s1/m1 genotype and CagA gene correlated.Results: The mother had the highest expression of VacA s1/m1-/cagA- with 19% (8/42), followed by the first child with 14.3% (6/42). The major roles for the vacA s1/m1+/cagA- were the mother and first child with 9.5% (4/42), followed by the remaining children with 4.8% (2/42). The vacA s1/m1-/cagA+ genotype was 7.1% (3/42) for the mother and 4.8% (2/42) for the father. Finally, the vacA s1/m1+/cagA+ genotype only appeared in the mother, son I, and son III with 2.4% (1/42).Conclusion: The vacA s1/m1/cagA genotypes predominated in the mother, suggesting potential transmission between the mother and child during the first years of life.Plain Language Summary:Helicobacter pylori is a bacterium that causes duodenal and gastric ulcers and is a risk factor for gastric cancer. It has been found in the dental plaque of children and adults. This study was conducted to identify if the mother can transmit the infection to her children. [ABSTRACT FROM AUTHOR]

Biological control by beneficial microorganisms is known to significantly reduce the effect of pests on crops yield. Among the biocontrol strategies is the use of entomopathogenic fungi such as Hirsutella citriformis, which has been applied to infect and kill hemipteran insect pests, including Diaphorina citri Kuwayama (Hemiptera: Liviidae) and Bactericera cockerelli Sulc. (Hemiptera: Triozidae). These biological agents are applied in the form of conidia that are often combined with other inert materials to facilitate application, protect conidia, and improve their shelf life. The aim of this study was to implement strategies for developing formulations to increase conidia shelf life. We evaluated gum produced from one strain and conidia from two different H. citriformis strains. Conidia were formulated by evaluating different concentrations of Acacia and Hirsutella gums to enhance conidia viability during storage at 4 °C or 25 °C. Results indicated that formulations maintained conidia viability for at least 90 d after storage at 25 °C (≥70% viability) and at least 120 d after storage at 4 °C, which was significantly (p ≤ 0.05) higher than that of the control, without observing changes in pH values. We also demonstrated 100% formulation purity from days 0 to 120, among all treatments. In conclusion, evaluated formulations maintained H. citriformis conidia viability for at least three months, when stored at 4 °C. [ABSTRACT FROM AUTHOR]

Ruta chalepensis is an herb used to treat various ailments, and its potential cytotoxic effects on different tumor cell lines have been extensively studied. The present study aimed to evaluate the cytotoxic activity of R. chalepensis methanol extract (RCME), sub-partitions obtained from solvents of increasing polarity, and major compounds, as well as their hemolytic, anti-hemolytic, and antioxidant potential. The in vitro cytotoxic activity against the human hepatocarcinoma (HEP-G2) and the murine lymphoma cell line (L5178Y-R) was evaluated using the colorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction assay, whereas selectivity indices (SIs) were determined by comparing cytotoxicity against normal African green monkey kidney cells (VERO) and human peripheral blood mononuclear cells (PBMC). Hemolytic and anti-hemolytic activities were evaluated on human erythrocytes. The most effective cytotoxic treatment was evaluated for nitric oxide release by J774A.1 macrophages. Antioxidant activity of R. chalepensis material was also determined. Results showed that RCME produced significant (p < 0.05) cytotoxicity in HEP-G2 (IC50 = 1.79 µg/mL) and L5178Y-R (IC50 = 1.60 µg/mL) cells and exhibited high SIs (291.50 and 114.80, respectively). In addition, the n-hexane fraction (RCHF) showed an IC50 of 18.31 µg/mL in HEP-G2 cells and an SI of 9.48 in VERO cells, whereas the chloroform fraction (RCCF) evidenced an IC50 of 1.60 µg/mL in L5178Y-R cells and an SI of 34.27 in PBMC cells. Chalepensin (CHL), rutamarin (RTM), and graveolin (GRV), which are major components of R. chalepensis, showed high activity against L5178Y-R cells, with IC50 of 9.15, 15.13 and SI of 45.08 µg/mL, respectively. In addition, CHL, RTM, and GRV showed SIs of 24.76, 9.98, and 3.52, respectively, when compared with PBMC cells. RCME at concentrations of 125 µg/mL and 250 µg/mL, significantly (p < 0.05) decreased nitrite production in J774A.1 cells, when exposed to lipopolysaccharide. This study demonstrated that RCME showed significant cytotoxic activity against HEP-G2 and L5178Y-R cells, without affecting normal VERO, PBMC, and J774A.1 cells. [ABSTRACT FROM AUTHOR]

Probiotics are effective to treat or prevent gastrointestinal infections, and microalgae have demonstrated important health-promoting effects and in some cases function as prebiotics. In this regard, the anti-rotavirus effect of Bifidobacterium longum and Chlorella sorokiniana by reducing viral infectivity is well known. However, their effect on immune response against rotavirus has not yet been investigated. Therefore, the aim of this study was to determine the role of Bifidobacterium longum and/or Chlorella sorokiniana in influencing an IFN type I-mediated antiviral response in rotavirus-infected cells. In pre-infection experiments, HT-29 cells were treated with B. longum and C. sorokiniana alone or in combination, followed by rotavirus infection, whereas in post-infection assays, HT-29 cells were treated after infection. The cells' mRNA was then purified to determine the relative expression level of IFN-α, IFN-β, and precursors of interferons such as RIG-I, IRF-3, and IRF-5 by qPCR. We showed that combination of B. longum and C. sorokiniana significantly increased IFN-α levels in pre-infection and IFN-β in post-infection assays, as compared with individual effects. Results indicate that B. longum, C. sorokiniana, or their combination improve cellular antiviral immune response. [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]

Hirsutella citriformis Speare is the only entomopathogenic fungus involved in Diaphorina citri Kuwayama natural epizootics. The aim of the present study was to evaluate different protein sources as supplements to stimulate Hirsutella citriformis growth, improve conidiation on solid culture, and evaluate its produced gum for conidia formulation against D. citri adults. Hirsutella citriformis INIFAP-Hir-2 strain was grown on agar media enriched with wheat bran, wheat germ, soy, amaranth, quinoa, and pumpkin seed, in addition to oat with wheat bran and/or amaranth. The results demonstrated that 2% wheat bran significantly (p < 0.05) promoted mycelium growth. However, 4% and 5% wheat bran achieved the highest conidiation (3.65 × 107 conidia/mL and 3.68 × 107 conidia/mL, respectively). Higher conidiation (p < 0.05) was observed on oat grains supplemented with wheat bran, as compared with culturing on oat grains without supplements (7.25 × 107 versus 5.22 × 107 conidia/g), after a 14 d instead of 21 d incubation period. After supplementing synthetic medium or oat grains with wheat bran and/or amaranth, INIFAP-Hir-2 conidiation increased, whereas production time was reduced. After using Acacia and Hirsutella gums to formulate conidia produced on wheat bran and amaranth at 4%, field trial results showed that the highest (p < 0.05) D. citri mortality was achieved by Hirsutella gum-formulated conidia (80.0%), followed by the Hirsutella gum control (57.8%). Furthermore, Acacia gum-formulated conidia caused 37.8%, whereas Acacia gum and negative controls induced 9% mortality. In conclusion, Hirsutella citriformis gum used to formulate its conidia improved biological control against D. citri adults. [ABSTRACT FROM AUTHOR]

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 were assessed as biofertilizers on pepper, under controlled conditions. Furthermore, in vitro antagonism assays were performed by confronting Bc and Bt isolate formulations against Xe isolates in direct (foliage) and indirect (resistance induction) phytopathogen biocontrol assays on pepper plants, which were grown under controlled conditions for 15 d after formulations treatment. Results. Isolates were identified as Bc and Bt. Formulations significantly improved pepper growth in seedbeds and pots, whereas in vitro bioassays demonstrated the bactericidal effect of Bc and Bt strains against Xe isolates. Furthermore, assays showed significant plant protection by F-BC26, F-BC08, and F-BT24 formulated strains against Xe. Conclusion. Results indicated that F-BT24 and F-BC26 isolates formulations promoted pepper growth and protected it against Xanthomonas euvesicatoria. [ABSTRACT FROM AUTHOR]

Medicinal plants are traditionally used in Mexico to treat diseases such as cancer. The present study aimed to evaluate the cytotoxic, antioxidant, and anti-hemolytic activity of 15 plants of ethnopharmacological use in Mexico. For this, plant methanol extracts were prepared by the Soxhlet method, after which their cytotoxic activity was evaluated against human hepatocellular carcinoma (HEP-G2) and monkey kidney epithelial (Vero) cells by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction colorimetric assay. The selectivity index (SI) of each extract was then determined by the IC50 ratio of normal to tumor cells. We showed that Ruta chalepensis extract possessed an IC50 of 1.79 µg/mL and 522.08 µg/mL against HEP-G2 and Vero cells, respectively, resulting in an SI of 291.50. Furthermore, antioxidant activity was evaluated by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging technique, where the best antioxidant potential was shown by the Heterotheca inuloides extract (IC50 = 19.24 µg/mL). Furthermore, the hemolytic potential was determined against human erythrocytes, which showed that the extracts with the highest anti-hemolytic activity were Smilax aspera (IC50 = 4.41 µg/mL) and Amphipterygium adstringens (IC50 = 5.35 µg/mL). In conclusion, we observed that R. chalepensis methanol extract possesses cytotoxic activity against HEP-G2 cells, without affecting non-tumorigenic Vero cells. Our results indicated the antitumor potential of medicinal plants used in Mexico. [ABSTRACT FROM AUTHOR]

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]

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]

The milk ring test is a detection assay for antibodies against Brucella in bovine milk. It has good sensitivity but tends to give false positive results. In this study, we standardized the application of the fluorescence polarization assay (FPA) for the detection of antibodies against B.melitensis in goat milk. We obtained negative serum and milk samples from healthy goat flocks in the northern zone of Nuevo León. Positive milk and negative, weak, and strong controls were obtained by mixing volumes of positive control serum with negative control milk. Milk samples were treated with citric acid, after which an FPA was performed. Results were then compared with the Rose Bengal test and the FPA in serum. Milk treatment allowed the quantification of antibodies in samples. Significant differences were found between the 2%, 4%, and 6% groups, compared with the control group (F3, 67 = 17.45, p < 0.0001) but not between the 2% and 4% groups (p = 0.0718). The cut-off value was 74.1 mP, with a sensitivity (Se) of 95% and a specificity (Sp) of 100%. Se and Sp values in field milk samples were 84% and 74.55%, respectively. Despite the FPA test on milk samples showed lower Se and Sp than the FPA test on serum samples, its cutoff may be adjusted. It may be recommended as a screening test in goat milk and become useful for the control and eradication of the disease. [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]

Equine infectious anemia (EIA) is a highly infectious disease in members of the Equidae family, caused by equine infectious anemia virus (EIAV). The disease severity ranges from subclinical to acute or chronic, and causes significant economic losses in the equine industry worldwide. Serologic tests for detection of EIAV infection have some concerns given the prolonged seroconversion time. Therefore, molecular methods are needed to improve surveillance programs for this disease. We attempted detection of EIAV in 6 clinical and 42 non-clinical horses in Nuevo Leon State, Mexico, using the agar gel immunodiffusion (AGID) test for antibody detection, and nested and hemi-nested PCR for detection of proviral DNA. We found that 6 of 6, 5 of 6, and 6 of 6 clinical horses were positive by AGID, nested PCR, and hemi-nested PCR, respectively, whereas 0 of 42, 1 of 42, and 9 of 42 non-clinical horses were positive by these tests, respectively. BLAST analysis of the 203-bp 5′-LTR/ tat segment of PCR product revealed 83–93% identity with EIAV isolates in GenBank and reference strains from other countries. By phylogenetic analysis, our Mexican samples were grouped in a different clade than other sequences reported worldwide, indicating that the LRT/ tat region represents an important target for the detection of non-clinical horses. [ABSTRACT FROM AUTHOR]

Background. Among entomopathogenic fungi, H. citriformis has been recognized as potential biocontrol agent against the Asian citrus psyllid Diaphorina citri (Hemiptera: Liviidae). Nevertheless, this fungus is poorly characterized. Previous molecular studies have shown high sequence similarities among strains, but significant differences in Diaphorina citri virulence. Objective. The aim of the present study was to determine mycelial compatibility and anastomosis, and nucleus numbers in mycelium and conidia of eight H. citriformis strains isolated from mycosed D. citri adults collected from several Mexican states. Methods. Mycelial compatibility and anastomosis evaluation was performed after pairing strains, leading to 36 confrontations, and cultured in chlorate minimum medium to obtain mutants for vegetative compatibility group. Results. Hypha or conidia nuclei were visualized with safranin-O and 3% KOH, and 0.05% trypan blue-lactophenol solution. H. citriformis strains showed compatibly and anastomosis events after confrontation. In addition, they showed one nucleus per conidium and mycelium section. It was not possible to obtain H. citriformis nit mutants from the chlorate concentrations tested. Conclusions. To date, this is the first report demonstrating mycelial compatibility, anastomosis occurrence, and hyphae and conidia nuclei number among H. citriformis strains. [ABSTRACT FROM AUTHOR]

Spodoptera frugiperda is a widely distributed insect pest that causes major economic losses in various crops, particularly maize. On the other hand, Beauveria bassiana is an entomopathogenic fungus that establishes symbiotic associations with many plants and contributes to tolerance against biotic and abiotic stresses. In the present work, in laboratory experiments, the effects of the B. bassiana strain GHA, in addition to a native strain (PTG4), delivered via seed treatment in maize seedlings, were evaluated on S. frugiperda growth, development, and mortality. We inoculated maize seeds with 1 × 106B. bassiana blastospores; then these seeds were germinated and grown to seedlings under growth chamber conditions. Third-instar S. frugiperda larvae were allowed to feed on B. bassiana-treated and -untreated (negative control) seedlings until reaching the sixth instar and transferred to an artificial diet until reaching adult stage. Results showed that larvae feeding on B. bassiana strain PTG4-treated plants prolonged their larval stage. Furthermore, feeding on plants treated with B. bassiana strains yielded fewer S. frugiperda male moths compared with feeding with the untreated control plants. Under field conditions, 1 × 106 (first trial) and 1 × 108 (second trial) of B. bassiana (GHA strain) blastospores were used for corn seed inoculation. In the first field trial, there were a higher number of larvae in the negative control plants compared to those in the plants treated with B. bassiana. No larvae were found in negative control and B. bassiana-treated plants in the second field trial. In conclusion, seed treatment with B. bassiana in maize reduced S. frugiperda infestation of maize plants in field trials. S. frugiperda development was also affected in laboratory trials. [ABSTRACT FROM AUTHOR]

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 isolates) to copper sulphate (CuS), copper gluconate (CuG), copper oxychloride + oxytetracycline hydrochloride (Cu + Ox), gentamicin + oxytetracycline hydrochloride (Gen + Ox), and gentamicin sulphate (GenS). Copper-resistance genes (copLAB) were detected by PCR analysis among isolates. Results: Thirty-seven foliage isolates were identified as Xanthomonas euvesicatoria (14%), which were associated with bacterial spot disease in jalapeño pepper. Tested Xanthomonas isolates were resistant to Cu-based compounds, but susceptible to Cu + Ox. All isolates were susceptible to Gen + Ox and GenS. CopLAB genes were detected in all but one strain. Conclusions: X. euvesicatoria (formally X. perforans) may be considered as an emerging pathogen of bacterial spot pepper in Mexico. Among disease management strategies, alternatives to copper should be taken into consideration. [ABSTRACT FROM AUTHOR]

The living organisms have never before in its evolutionary history been exposed to electromagnetic radiation, especially to extremely low-frequency electromagnetic fields (ELF-EMFs) that are ubiquitous in the modern environment. There are some investigations that suggest that such fields have detrimental effects on cells. On the other hand, there have been many attempts to develop radioprotective agents. In the present study, BALB/c mice were exposed to 2.0 mT ELF-EMFs at 60 Hz frequency for 72 h, in the presence or absence of resveratrol (15 mg/kg), using sham-exposed mice and saline solution as negative controls, after which clastogenic effects were assessed by the micronucleus (MN) test. Resveratrol was shown to significantly (p<0.05) reduce ELF-EMFs-induced clastogenic effect on mice bone marrow MN. These findings suggest a potential use of resveratrol for radioprotection. [ABSTRACT FROM AUTHOR]

Microalgae and probiotics such as Bifidobacterium and Lactobacillus genera are associated with human beneficial effects. The aim of this study was to evaluate the activity of Chlorella sorokiniana on Bifidobacterium longum and Lactobacillus plantarum viability in a dairy product (flan) and its microbial effect against rotavirus, which is one of the major diarrhea-causing pathogens worldwide. Microalge were isolated from a Mexican river and characterized by molecular tools. Their prebiotic activity was evaluated by determining Bifidobacterium longum and Lactobacillus plantarum shelf-life after incorporation in the food matrix. In addition, HT-29 cells were infected with rotavirus Wa and treated with 1 × 109 CFU/mL L. plantarum and B. longum metabolites alone or in combination with 1 × 109 cells/mL Chlorella sorokiniana ; viral titers in probiotics- and/or microalgae-treated cells were evaluated for antiviral activity. Results indicated that C. sorokiniana not only significantly (p < 0.05) improved L. plantarum and B. longum viability in flan, but also increased their antiviral activity; potent anti-rotavirus effect of C. sorokiniana alone was observed. Although more studies are needed, results suggest that incorporation of this microalga into a dairy product confers enhanced viability and antiviral effects, which indicates that C. sorokiniana might be used as an ingredient to design products with additional health benefits. [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]

Background Microalgae are a widely distributed group of prokaryotic and eukaryotic photosynthetic microorganisms that use a number of substances present in wastewater to produce a variety of biotechnological and nutritional biomolecules. Methods Production ofamino acids and acylcarnitine by Chlorella vulgaris and Chlorella sorokiniana was determined after 13 d of culture in wastewater, under various culture conditions. Wastewater was collected from “La Encantada” stream, located in Saltillo, Coahuila, Mexico. Microalgae was cultured at 23°C and natural day light, including the use of the following conditions: (1) extra light (12:12 light:dark cycles, 1,380 lumens), (2) agitation (130 rpm), and (3) both conditions, until exponential phase. Supernatant products were then analyzed by liquid chromatograph coupled to mass spectrometry. In addition, metabolomic profiles related to growing conditions were evaluated. Results Amino acids and acylcarnitine production by C. sorokiniana and C. vulgaris resulted in higher Ala and Leu concentrations by C. vulgaris compared with control, where control produced Gly and Pro in higher amounts compared with C. sorokiniana. Tyr, Phe, Val, and Cit were detected in lower amounts under light and shaking culture conditions. High concentrations of C0 acylcarnitines were produced by both microalgae compared with control, where C. sorokiniana production was independent of culture conditions, whereas C. vulgaris one was stimulated by shaking. C4 production was higher by C. sorokiniana compared with control. Furthermore, C4, C6DC, C14:1, C14:2, and C18:1OH production by microalga was low in all culture conditions. Conclusion Microalgae produced essential amino acids and nutritionally important carnitines from wastewater. In addition, C. sorokiniana biomass has higher potential as animal nutrient supplement, as compared with that of C. vulgaris. [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]

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]