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Candidemia is an opportunistic mycosis with high morbidity and mortality rates. Even though Candida albicans is the main causative agent, other Candida species, such as Candida tropicalis, are relevant etiological agents of candidiasis and candidemia. Compared with C. albicans, there is currently limited information about C. tropicalis' biological aspects, including those related to the cell wall and the interaction with the host. Currently, it is known that its cell wall contains O-linked mannans, and the contribution of these structures to cell fitness has previously been addressed using cells subjected to chemical treatments or in mutants where O-linked mannans and other wall components are affected. Here, we generated a C. tropicalis pmt2∆ null mutant, which was affected in the first step of the O-linked mannosylation pathway. The null mutant was viable, contrasting with C. albicans where this gene is essential. The phenotypical characterization showed that O-linked mannans were required for filamentation; proper cell wall integrity and organization; biofilm formation; protein secretion; and adhesion to extracellular matrix components, in particular to fibronectin; and type I and type II collagen. When interacting with human innate immune cells, it was found that this cell wall structure is dispensable for cytokine production, but mutant cells were more phagocytosed by monocyte-derived macrophages. Furthermore, the null mutant cells showed virulence attenuation in Galleria mellonella larvae. Thus, O-linked mannans are minor components of the cell wall that are involved in different aspects of C. tropicalis' biology.

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Opuntia ficus-indica has always interacted with many phytophagous insects; two of them are Dactylopius coccus and D. opuntiae. Fine cochineal (D. coccus) is produced to extract carminic acid, and D. opuntiae, or wild cochineal, is an invasive pest of O. ficus-indica in more than 20 countries around the world. Despite the economic and environmental relevance of this cactus, D. opuntiae, and D. coccus, there are few studies that have explored volatile organic compounds (VOCs) derived from the plant-insect interaction. The aim of this work was to determine the VOCs produced by D. coccus and D. opuntiae and to identify different VOCs in cladodes infested by each Dactylopius species. The VOCs (essential oils) were obtained by hydrodistillation and identified by GC-MS. A total of 66 VOCs from both Dactylopius species were identified, and 125 from the Esmeralda and Rojo Pelón cultivars infested by D. coccus and D. opuntiae, respectively, were determined. Differential VOC production due to infestation by each Dactylopius species was also found. Some changes in methyl salicylate, terpenes such as linalool, or the alcohol p-vinylguaiacol were related to Dactylopius feeding on the cladodes of their respective cultivars. Changes in these VOCs and their probable role in plant defense mechanisms should receive more attention because this knowledge could improve D. coccus rearing or its inclusion in breeding programs for D. opuntiae control in regions where it is a key pest of O. ficus-indica.

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Candida glabrata (Nakaseomyces glabrata) is an emergent and opportunistic fungal pathogen that colonizes and persists in different niches within its human host. In this work, we studied five clinical isolates from one patient (P7), that have a clonal origin, and all of which come from blood cultures except one, P7-3, obtained from a urine culture. We found phenotypic variation such as sensitivity to high temperature, oxidative stress, susceptibility to two classes of antifungal agents, and cell wall porosity. Only isolate P7-3 is highly resistant to the echinocandin caspofungin while the other four isolates from P7 are sensitive. However, this same isolate P7-3, is the only one that displays susceptibility to fluconazole (FLC), while the rest of the isolates are resistant to this antifungal. We sequenced the PDR1 gene which encodes a transcription factor required to induce the expression of several genes involved in the resistance to FLC and found that all the isolates encode for the same Pdr1 amino acid sequence except for the last isolate P7-5, which contains a single amino acid change, G1099C in the putative Pdr1 transactivation domain. Consistent with the resistance to FLC, we found that the CDR1 gene, encoding the main drug efflux pump in C. glabrata, is highly overexpressed in the FLC-resistant isolates, but not in the FLC-sensitive P7-3. In addition, the resistance to FLC observed in these isolates is dependent on the PDR1 gene. Additionally, we found that all P7 isolates have a different proportion of cell wall carbohydrates compared to our standard strains CBS138 and BG14. In P7 isolates, mannan is the most abundant cell wall component, whereas ß-glucan is the most abundant component in our standard strains. Consistently, all P7 isolates have a relatively low cell wall porosity compared to our standard strains. These data show phenotypic and genotypic variability between clonal isolates from different niches within a single host, suggesting microevolution of C. glabrata during an infection.

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Dactylopius opuntiae is an insect pest that contains at least carminic acid, which has antioxidant properties. Since there is a relationship between the antioxidant ability and preservative action of compounds applied to meat products, the purpose of this study was to evaluate the antioxidant activity and usefulness of a D. opuntiae extract for beef patty preservation. The insects were bred and processed to obtain a liquid extract. For the extract, its carminic acid content, antioxidant activity against two free radicals, and actions on food quality parameters were determined. The D. opuntiae dry powder contained 2.91% w/w carminic acid, while the liquid extract exhibited an IC50 value of 3437.8 ± 67.8 and 19633.0 ± 674.5 µg/mL against the DPPH and ABTS radicals. Nevertheless, these antioxidant actions were lower than those found in a D. coccus extract. The D. opuntiae extract improved in a short time the redness and yellowness, eliminated the unfavorable effect of their vehicle on the MetMb level, and greatly reduced the TBARS formation. For the first time, an extract of D. opuntiae was applied to beef patties, and its beneficial antioxidant action on meat acceptance parameters was confirmed, which has potential commercial applications.

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Two patients were admitted to the dental clinic to evaluate two right mandibular first molars (both FDI no. 46). In Case 1, there was an accidental instrument separation, which was thought to have been bypassed; however, the instrument was located beyond the apical foramen, in the alveolar bone. The 1-week follow-up revealed that the fragment was close to the inferior alveolar nerve, thus allowing surgical removal to be performed. In Case 2, two separated instruments located in the apical third of the mesiobuccal and mesiolingual canals were removed using the HBW ultrasonic ring coupled to ISO 10 and 15 hand instruments. The 3-month and 1-year follow-ups (Case 1), and the 2-year and 3-year follow-ups (Case 2) showed a favourable evolution in both cases. It can be concluded that both the surgical approach and the HBW ultrasonic ring are viable options for the removal of separated instruments in unfavourable locations.

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Tagetes parryi is a plant empirically used to treat gastrointestinal and inflammatory diseases, its essential oil (EOTP) was obtained from the aerial parts, and the composition was elucidated by GC-MS. The in vivo and in vitro anti-inflammatory activities and the antinociceptive activity of EOTP and (1S)-(-)-verbenone (VERB) were assessed. The major compounds identified for EOTP were verbenone (33.39%), dihydrotagetone (26.88%), and tagetone (20.8%). EOTP and VERB diminished the ear oedema induced with TPA by 93.77 % and 81.13 %, respectively. EOTP and VERB decreased inflammation in a 12-O-tetradecanoylphorbol-13-acetate (TPA) chronic model with ED50 = 54.95 mg/kg and 45.24 mg/kg, respectively. EOTP (15 µg/mL) inhibited the in vitro production of the pro-inflammatory mediators NO (67.02%), TNF-α (69.21%), and IL-6 (58.44%) in LPS-stimulated macrophages. In the acetic induced writhing test, EOTP and VERB showed antinociceptive effects with ED50 = 84.93 mg/kg and ED50 = 45.24 mg/kg, respectively. In phase 1 of the formalin test, EOTP and VERB showed no antinociceptive effects, whereas in phase 2, EOTP (ED50 = 35.45 mg/kg) and VERB (ED50 = 24.84 mg/kg) showed antinociceptive effects. The antinociceptive actions of ETOP and VERB were blocked with the co-administration of L-NAME. This study suggests that EOTP and VERB might be used in the treatment of pain and inflammatory problems.

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Objetivo: Describir el perfil microbiológico de los microorganismos aislados de pacientes de las unidades de cuidados críticos de un hospital de la región Lambayeque en el 2019 ­ 2020. Materiales y métodos: Estudio descriptivo, retrospectivo, transversal y de enfoque cuantitativo. Se realizó un estudio censal a 332 pacientes de las unidades de cuidados críticos con cultivo microbiológico positivo registrado en el archivo del laboratorio de microbiología del Hospital Regional Lambayeque en el 2019 - 2020. Se utilizó el software estadístico Info stat v8 para el análisis estadístico. Resultados: La mediana de edad fue de 50 años a predominio de sexo masculino (55,1%). La muestra de cultivo más frecuente fue la secreción bronquial (35,8%). Los microorganismos que se aislaron con mayor frecuencia fueron A. baumannii complex (27,7%) resistente a meropenem e imipenem con 90,7% y 89,3% respectivamente, P. aeruginosa (13,9%) resistente a cefepime con 55,8% y 61,1% para Piperacilina / tazobactam, E. coli (11,1%) resistente a ampicilina con 94,7%; y K. pneumoniae (9,9%) resistente a ampicilina/sulbactam en un 79,2%. Conclusión: Los microorganismos más frecuentes aislados de la población de estudio, fueron A. baumannii complex, P. aeruginosa, E. coli y K. pneumoniae; aislados mayoritariamente de secreciones respiratorias, de los cuales, los dos primeros presentaron alta resistencia a carbapenémicos y aminoglucósidos, y en los dos siguientes, la mitad fueron BLEE.

Objective: To describe the microbiological profile of microorganisms isolated from patients in critical care units of a hospital in the Lambayeque region in 2019-2020. Materials and methods: Descriptive, retrospective, cross-sectional study with a quantitative approach. A census study was carried out on 332 patients from critical care units with a positive microbiological culture registered in the file of the microbiology laboratory of the Lambayeque Regional Hospital in 2019-2020. The statistical software Info stat v8 was used for statistical analysis. Results: The median age was 50 years, predominantly male (55.1%). The most frequent culture sample was bronchial secretion (35.8%). The most frequently isolated microorganisms were A. baumannii complex (27.7%) resistant to meropenem and imipenem with 90.7% and 89.3% respectively, P. aeruginosa (13.9%) resistant to cefepime with 55.8% and 61.1% for Piperacillin / tazobactam, E. coli (11.1%) resistant to ampicillin with 94.7%; and K. pneumoniae (9.9%) resistant to ampicillin / sulbactam by 79.2%. Conclusion: The most frequent microorganisms isolated from the study population were the A. baumannii complex, P. aeruginosa, E. coli and K. pneumoniae; isolated mainly from respiratory secretions, of which the first two showed high resistance to carbapenems and aminoglycosides, and in the next two, half were ESBL.

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Ulomoides dermestoides are used as a broad-spectrum medical insect in the alternative treatment of various diseases. Preliminary volatilome studies carried out to date have shown, as the main components, methyl-1,4-benzoquinone, ethyl-1,4-benzoquinone, 1-tridecene, 1-pentadecene, and limonene. This work focused on the production of metabolites and their metabolic variations in U. dermestoides under stress conditions to provide additional valuable information to help better understand the broad-spectrum medical uses. To this end, VOCs were characterized by HS-SPME with PEG and CAR/PDMS fibers, and the first reported insect essential oils were obtained. In HS-SMPE, we found 17 terpenes, six quinones, five alkenes, and four aromatic compounds; in the essential oils, 53 terpenes, 54 carboxylic acids and derivatives, three alkynes, 12 alkenes (1-Pentadecene, EOT1: 77.6% and EOT2: 57.9%), 28 alkanes, nine alkyl disulfides, three aromatic compounds, 19 alcohols, three quinones, and 12 aldehydes were identified. Between both study approaches, a total of 171 secondary metabolites were identified with no previous report for U. dermestoides. A considerable number of the identified metabolites showed previous studies of the activity of pharmacological interest. Therefore, considering the wide variety of activities reported for these metabolites, this work allows a broader vision of the therapeutic potential of U. dermestoides in traditional medicine.

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The assertion made by Wu et al. that aromaticity may have considerable implications for molecular design motivated us to use nucleus-independent chemical shifts (NICS) as an aromaticity criterion to evaluate the antifungal activity of two series of indol-4-ones. A linear regression analysis of NICS and antifungal activity showed that both tested variables were significantly related (p < 0.05); when aromaticity increased, the antifungal activity decreased for series I and increased for series II. To verify the validity of the obtained equations, a new set of 44 benzofuran-4-ones was designed by replacing the nitrogen atom of the five-membered ring with oxygen in indol-4-ones. The NICS(0) and NICS(1) of benzofuran-4-ones were calculated and used to predict their biological activities using the previous equations. A set of 10 benzofuran-4-ones was synthesized and tested in eight human pathogenic fungi, showing the validity of the equations. The minimum inhibitory concentration (MIC) in yeasts was 31.25 µg·mL-1 for Candida glabrata, Candida krusei and Candida guilliermondii with compounds 15-32, 15-15 and 15-1. The MIC for filamentous fungi was 1.95 µg·mL-1 for Aspergillus niger for compounds 15-1, 15-33 and 15-34. The results obtained support the use of NICS in the molecular design of compounds with antifungal activity.

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Candida albicans, Candida glabrata, Candida parapsilosis and Candida tropicalis are the four most common human fungal pathogens isolated that can cause superficial and invasive infections. It has been shown that specific metabolites present in the secretomes of these fungal pathogens are important for their virulence. C. glabrata is the second most common isolate world-wide and has an innate resistance to azoles, xenobiotics and oxidative stress that allows this fungal pathogen to evade the immune response and persist within the host. Here, we analyzed and compared the C. glabrata secretome with those of C. albicans, C. parapsilosis, C. tropicalis and the non-pathogenic yeast Saccharomyces cerevisiae. In C. glabrata, we identified a different number of metabolites depending on the growth media: 12 in synthetic complete media (SC), 27 in SC-glutamic acid and 23 in rich media (YPD). C. glabrata specific metabolites are 1-dodecene (0.09 ± 0.11%), 2,5-dimethylundecane (1.01 ± 0.19%), 3,7-dimethyldecane (0.14 ± 0.15%), and octadecane (0.4 ± 0.53%). The metabolites that are shared with C. albicans, C. glabrata, C. parapsilosis, C. tropicalis and S. cerevisiae are phenylethanol, which is synthesized from phenylalanine, and eicosane and nonanoic acid (identified as trimethylsilyl ester), which are synthesized from fatty acid metabolism. Phenylethanol is the most abundant metabolite in all fungi tested: 26.36 ± 17.42% (C. glabrata), 46.77 ± 15.58% (C. albicans), 49.76 ± 18.43% (C. tropicalis), 5.72 ± 0.66% (C. parapsilosis.) and 44.58 ± 27.91% (S. cerevisiae). The analysis of C. glabrata's secretome will allow us to further our understanding of the possible role these metabolites could play in its virulence.

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