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Global dispersion, hospital outbreaks, and lineage relationships between emerging antibiotic-resistant strains such as Klebsiella pneumoniae are of public health interest. This study aimed to isolate and identify K. pneumoniae clones from third-level healthcare hospitals in Mexico to establish their multidrug-resistant phenotype, phylogeny, and prevalence. Biological and abiotic surface samples were used to isolate K. pneumoniae strains and to test their antibiotic susceptibility to classify them. The housekeeping genes: gapA, InfB, mdh, pgi, phoE, ropB, and tonB were used for multilocus sequence typing (MLST). Phylogenetic networks were constructed with 48 strains. Isolated strains (93) were mainly from urine and blood, 96% were resistant to ampicillin as expected, 60% were extended-spectrum ß-lactamases (ESBL), 98% were susceptible to ertapenem and meropenem and 99% were susceptible to imipenem, 46% were multi-drug resistant (MDR), 17% were extensively-drug resistant (XDR), 1% were pan-drug resistant (PDR), and 36% were not classified. The tonB, mdh, and phoE genes were the most variable, and the InfB gene showed positive selection. The most prevalent sequence types (STs) were ST551 (six clones), ST405 (six clones), ST1088 (four clones), ST25 (four clones), ST392 (three clones), and ST36 (two clones). ST706 was PDR, and ST1088 clones were MDR; neither of these STs has been reported in Mexico. The strains analyzed were from different hospitals and locations; thus, it is important to maintain antibiotic surveillance and avoid clone dissemination to prevent outbreaks, adaptation to antibiotics, and the transmission of antibiotic resistance.

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Stem blight is a destructive woody disease of blueberry (Vaccinium corymbosum) caused by several species of the family Botryosphaeriaceae. A field survey was conducted in the mayor blueberry production area of Chile, comprising latitudes 32°49'S to 40°55'S, to determine the occurrence and distribution of Botryosphaeriaceae in the region. Together, a multilocus analysis, morphological characterization, and phytopathogenicity testing were used to identify 51 Neofusicoccum isolates belonging to N. nonquaesitum (28 strains), N. parvum (22 strains), and N. australe (1 strain). Of these, N. parvum and N. nonquaesitum were the most commonly found, with N. parvum most frequent from latitude 37°40'S to the north and N. nonquaesitum predominantly located from the same latitude toward the south. Morphological traits of the isolates were consistent with the species identified by molecular techniques, despite the overlapping of conidial size of some isolates among species. Pathogenicity trials showed that the three species were pathogenic to blueberry plants and revealed that N. parvum and N. nonquaesitum were the most aggressive species, although variability in virulence was observed among isolates of N. parvum and N. nonquaesitum.

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Beauveria pseudobassiana RGM 2184 has shown 80% maximum efficacy against the pest Lobesia botrana in the autumn and winter seasons. This suggests that the strain possesses an interesting battery of enzymes that are cold-adapted to penetrate the thick and hydrophobic cocoon of L. botrana. In this study, screening of the proteolytic, lipolytic, and chitinolytic activity of enzyme extracts secreted by the RGM 2184 strain was carried out in various culture media. The enzyme extracts with the highest activity were subjected to zymography and mass spectrometry. These analyses allowed the identification of two proteases, two lipases, and three chitinases. Comparative analysis indicated that the degree of similarity between these enzymes was substantially reduced when the highest degree of taxonomic relatedness between RGM 2184 and the entomopathogenic fungus strain was at the family level. These results suggest that there is a wide variety of exoenzymes in entomopathogenic fungi species belonging to the order Hypocreales. On the other hand, exoenzyme extract exposure of cocoons and pupae of L. botrana provoked damage at 10 °C. Additionally, an analysis of the amino acid composition of the RGM 2184 exoenzyme grouped them close to the cold-adapted protein cluster. These results support the use of this strain to control pests in autumn and winter. Additionally, these antecedents can form a scaffold for the future characterization of these exoenzymes along with the optimization of the strain's biocontrol ability by overexpressing them.

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The B. safensis RGM 2450 and B. siamensis RGM 2529 strains were isolated from the rhizosphere of plants presenting resilience to abiotic and biotic stress conditions. To understand the implications of bacteria in resilience, a genomic and experimental analysis was carried out on their biostimulant and phytopathogenic antagonist properties. Genome analyses of both strains indicated that they have the potential to synthesize bioactive compounds such as the battery of non-ribosomal peptides, polyketides, extracellular enzymes and phytohormones. These results were consistent with the antagonistic activities of both strains against the phytopathogens Botrytis cinerea, Colletotrichum acutatum, Fusarium oxysporum and Phytophtora cinnamomi. They also showed the capacity to solubilize phosphorus, fix nitrogen and produce indole acetic acid. This was observed in tomato seedlings grown from seeds inoculated with the mixture of strains which presented significantly greater length as well as wet and dry weight in comparison with the treatments individually inoculated with each strain and the control. Accordingly, the combination of B. safensis RGM 2450 and B. siamensis RGM 2529 showed synergistic biostimulant activity. These findings contribute new knowledge of the genomic and metabolomic properties taking part in the symbiotic interactions between these strains and the plants and uphold the combined use of both strains as a biostimulant.

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The entomopathogenic fungus Beauveria pseudobassiana strain RGM 2184 can reach a maximum efficacy of 80% against the quarantine pest Lobesia botrana in field assays. In this study, the RGM 2184 genome was sequenced, and genome mining analyses were performed to predict the factors involved in its insecticidal activity. Additionally, the metabolic profiling of the RMG 2184 culture's supernatants was analyzed by mass spectrometry, and the insecticidal activity from one of these extracts was evaluated in Galleria mellonella larvae. The genome analysis resulted in 114 genes encoding for extracellular enzymes, four biosynthetic gene clusters reported as producers of insecticidal and bactericidal factors (oosporein, beauvericin, desmethylbassianin, and beauveriolide), 20 toxins, and at least 40 undescribed potential biocontrol factors (polyketides and nonribosomal peptides). Comparative genomic analysis revealed that 65-95% of these genes are Beauveria genus-specific. Metabolic profiling of supernatant extracts from RGM 2184 cultures exhibited secondary metabolites such as beauveriolide, oosporein, inflatin C, and bassiatin. However, a number of detected metabolites still remain undescribed. The metabolite extract caused 79% mortality of Galleria mellonella larvae at 28 days. The results of this research lay the groundwork for the study of new insecticidal molecules.

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BACKGROUND: Among older people, physical exercise improves cognitive function, aerobic fitness, and thus functional independence. AIM: To determine the effects of a walking training program on aerobic fitness and cognitive function in older women with type 2 diabetes mellitus. MATERIAL AND METHODS: An experimental study was carried out in 76 women with type 2 diabetes mellitus aged between 64 and 78 years. Thirty-eight women in the exercise group (EG) participated in a controlled walking program 3 times a week for 48 sessions (60min /day) and 38 women in the control group (CG) were not trained. Weight, height, body mass index (BMI), estimated maximal oxygen uptake (VO2max), and cognitive function using the Minimental test were evaluated at baseline and the end of the intervention. RESULTS: The Minimental test improved significantly in the exercise group and did not change in the control group. Estimated VO-2max improved in women aged between 69 and 78 years. The distance walked in 6 minutes increased in all women of the experimental group. No changes in these parameters were observed in the control group. CONCLUSIONS: A structured walking program improved cognitive function, estimated aerobic capacity, and walking distance in these diabetic women.

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During the last two seasons, an unusual fruit rot was observed in four orchards of sweet Japanese plum (Prunus salicina) cultivars located in the Chilean Central Valley (30°00'S, 70°42'W). The incidence was 5% in Black Majesty, 4% in Red Lyon, and 6% in Sweet Mary cultivars in 2020. Fruits in the field showed a firm, dehydrated, and slightly sunken rot on the blossom end, along with rough and irregular epidermis in the affected area. Internally, the fruit flesh appeared light to dark-brown or olive-green. Symptomatic fruits (n=119) were superficially disinfected (75% ethanol) and, pieces of the pericarp (3 x 3 mm) were removed and placed on potato dextrose agar (PDA). Isolates of Alternaria spp. were obtained and 9 of these were selected for identification. Colonies were dark olive to gray-brown with white margins, small, catenulate and muriform conidia, produced in single or branched conidiophores. Isolates produced brown to golden-brown, ovoid, ellipsoidal to obclavate conidia with dimensions of 19.7 to 26.7 × 10.0 to 11.9 µm with two to four transverse and zero to three longitudinal septa on 0.05× PDA (Pryor and Michailides 2002) after 7 d at 20°C under 10/14 h light/dark cycles. A molecular analysis was performed by sequencing the nuclear genes RNA polymerase II subunit (RPB2), plasma membrane ATPase (ATP), and the calmodulin (Cal) gene using primers RPB2-5F2/fRPB2-7cR, ATPDF1/ATPDR1, and CALDF1/CALDR1, respectively (Lawrence et al. 2013; Woudenberg et al. 2013). A BLAST search revealed the presence of Alternaria spp. with a 99% to 100% identity with the reference sequences of A. alternata (JQ905182, JQ671874, JQ646208), A. arborescens (JQ646487, JQ671880, JQ646214), and A. tenuissima (JQ811961, JQ811989, JQ646209). Maximum parsimony phylogenetic analysis confirmed the identifications. Sequences were deposited in GenBank as numbers MW514249 to MW514257, MT872324 to MT872332, and MT872314 to MT872322 for RPB2, ATP, and Cal sequences, respectively. All these Alternaria isolates were deposited in the Colección Chilena de Recursos Genéticos Microbianos - INIA, Chillán Chile (RGM3069 to RGM3077). Pathogenicity of A. alternata (n=4), A. arborescens (n=3) and, A. tenuissima (n=2) was tested in Red Lyon plum fruits. Plums were disinfected in 1% sodium hypochlorite for 2 min, rinsed in sterile distilled water for 1 min and dried on absorbent towels in a laminar flow hood. Then, the plums were wounded on the blossom end with a sterile needle (1 x 0.5 mm), inoculated with 10 µl of a conidial suspension (106 conidia/ml), wrapped with Parafilm and maintained in a humid chamber (>95% relative humidity). An equal number of fruits wounded and inoculated with sterile water were used as a control. After 7 days at 20°C, all inoculated fruits developed a dark-brown firm rot with lesion lengths of 24.4 (±3.0) mm, 19.6 (±0.7) mm, and 16.8 (±2.4) mm for A. alternata, A. arborescens and A. tenuissima, respectively. A. alternata was the most aggressive species (P < 0.001). Control fruits remained asymptomatic. Koch's postulates were fulfilled after the re-isolating the causal agent from the border of the lesions. Leaf spots and fruit rots caused by Alternaria isolates have been reported in stone fruits, including plums (Kim et al. 2005; Long et al. 2021; Moosa et al., 2019; Yang et al. 2014). To our knowledge, this is the first report of A. alternata, A. arborescens, and A. tenuissima associated with fruit rot in sweet Japanese plum cultivars in the field, in Chile.

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BACKGROUND: Among older people, physical exercise improves cognitive function, aerobic fitness, and thus functional independence. Aim: To determine the effects of a walking training program on aerobic fitness and cognitive function in older women with type 2 diabetes mellitus. MATERRIAL AND METHODS: An experimental study was carried out in 76 women with type 2 diabetes mellitus aged between 64 and 78 years. Thirty-eight women in the exercise group (EG) participated in a controlled walking program 3 times a week for 48 sessions (60min /day) and 38 women in the control group (CG) were not trained. Weight, height, body mass index (BMI), estimated maximal oxygen uptake (VO2max), and cognitive function using the Minimental test were evaluated at baseline and the end of the intervention. RESULTS: The Minimental test improved significantly in the exercise group and did not change in the control group. Estimated VO-2max improved in women aged between 69 and 78 years. The distance walked in 6 minutes increased in all women of the experimental group. No changes in these parameters were observed in the control group. Conclusions: A structured walking program improved cognitive function, estimated aerobic capacity, and walking distance in these diabetic women.

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Lobesia botrana (Denis and Shiffermüller) (Lepidoptera: Tortricidae) is one of the main pests that affect the production and export of table grapes in Chile. Because this pest has quarantine status, the fruit must be fumigated with methyl bromide, which reduces the fruit's export competitiveness in the destination market. In the present study, to help resolve this issue, six native entomopathogenic fungi were identified through multilocus analysis, including three Beauveria pseudobassiana and three Metarhizium robertsii. These fungi were evaluated in the laboratory to control L. botrana in its pupal stage in a silk cocoon and compared against a biological control product. Formulations with additional carbon sources improved the performance of the fungi. The treatments with outstanding performance contained the fungal strains B. pseudobassiana RGM 2184 and M. robertsii RGM 678. These strains were evaluated in the field during the winter season in two different regions of the country; the strains reached maximum efficacies of 80% and 88%, respectively, at 21 days post first application. Therefore, entomopathogenic fungi can contribute to reducing pupal populations in winter, thereby decreasing the moth population in spring-summer.