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Objectives. To determine the antimicrobial potential of marine actinomycetes against drug-resistant pathogens represented by strains of methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecalis (VRE). Materials and methods. Strains of actinomycetes (29) isolated from marine sediment were evaluated by their characteristics in two culture media and by testing their inhibitory capacity by in vitro antagonism against multi-drug resistant (MDR) pathogenic bacteria for MRSA and VRE. Organic extracts of 3 selected actinomicetes were processed to determine the minimum inhibitory concentration (MIC) of the active compound. Results. Most isolated actinomycetes belong to a homogeneous group of write-gray actinomycetes with a good growth in Marine Agar. The inhibitory rates of the isolates were above 85% for both pathogens with inhibition zones greater than 69 and 78 mm in diameter for MRSA and VRE respectively. Dichloromethane extracts of 3 isolates (I-400A, B1-T61, M10-77) showed strong inhibitory activity of both pathogens, M10-77 being the highest actinomycete strain with antibiotic activity against methicillin-resistant S. aureus ATCC 43300 and vancomycin-resistant E. faecalis ATCC 51299 with a minimum inhibitory concentrations (MIC) of 7.9 and 31.7 µg/ml respectively. Phylogenetic analysis of M10-77 strain showed 99% similarity with the marine species Streptomyces erythrogriseus. Conclusions. Marine sediments of the central coast of Peru, are a source of actinomycetes strains showing high capacity to produce bioactive compounds able to inhibit pathogens classified as multi-drugresistant such as methicillin-resistant S. aureus and vancomycin-resistant E. faecalis. [ABSTRACT FROM AUTHOR]

Prospective sampling activities of intertidal invertebrates in the Ancon Bay (Lima, Peru) were done in order to select marine bacteria producing antimicrobial substances. The study included the isolation of bacteria in marine agar, in vitro antimicrobial susceptibility testing and electronic microscopic observations. We report the isolation, phenotypical characterization and antimicrobial properties of 10 strains of marine bacteria including the genus Vibrio, Pseudomonas, and Flavobacterium, and the order Actinomycetae that inhibit human pathogens. The results indicate that the marine invertebrates would be sources of bacteria producing antibiotic substances. [ABSTRACT FROM AUTHOR]

Abstract: A total of 30 strains of Yersinia ruckeri causing recent outbreaks in Peruvian trout culture systems, were studied by means of biochemical characteristics, serology, lipopolysaccharide (LPS) and outer membrane protein (OMP) analysis, and ERIC and REP PCR fingerprinting. All the Peruvian isolates were found to be fermentative, oxidase negative and positive for decarboxylation of lysine and ornithine and utilization of glucose and mannitol, allowing their presumptive identification as Y. ruckeri. Sequencing of the 16S rRNA gene confirmed that isolates were indeed Y. ruckeri (>99.98% identity). Although most of the strains studied were motile and lipase positive corresponding to the biotype 1 of Y. ruckeri, 5 of these strains were negative from both tests, being identified as biotype 2. In addition, drug susceptibility tests determined high sensitivity to sulfamethoxazole/trimethoprim, oxytetracycline, ampicillin and enrofloxacin in all the isolates. Serologically, all the Peruvian strains studied were identified as belonging to the serotype O1 subgroup a. Analysis of the lipopolysaccharide (LPS) as well as total and outer membrane proteins (OMPs) profiles and the correspondent inmunoblotting, supported these results. Genotyping performed by means of ERIC- and REP-PCR determined major correlation of the Peruvian isolates with the type strain NCIMB 2194T regardless of the biotype. [Copyright &y& Elsevier]

Cajamarca is an important Andean livestock production area located in northern Peru and at the same time endemic in a poorly studied disease known as paramphistomosis. The purpose of this research was to calculate the frequency of paramphistomids in sheep (Ovis aries) slaughtered in the Camal Municipal de Cajamarca, located in the city of Cajamarca. Between the months of February to September 2019, 386 samples of rumen-reticulum were collected that were later classified by age and origin of the animals. Transferred to the laboratory, the stomach contents were emptied; they were examined meticulously and exhaustively in order to find, collect and recognize the parasites adhering to the walls of the compartments. Nineteen samples were positive for Calicophoron microbothrioides in the rumen and none in the reticulum, thus obtaining a frequency of 4.92% in the presentation of paramphistomids in the sampled sheep. According to the origin, the town of Chanta presented a higher frequency with 9.09% and Bambamarca had the lowest frequency with 2.86%. In the age groups, sheep from 2 to 2.5 years old showed a 5.76% presence of paramphistomids and 3.33% of those 4 years old and older were positive. Pearson's correlation coefficient (r = -0.25473762) indicates that there is a low and inversely proportional negative relationship between age and frequency. Finally, with the Chi-square test, no significant difference was obtained between the place of origin and the number of positive cases., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Introduction: Adjuvant chemo radiotherapy is the standard treatment in Western countries in gastric cancer patients submitted to curative resection. INT0116 pivotal trial established adjuvant chemo radiation as the standard care for resected high risk adenocarcinoma of the stomach in US however was hampered by suboptimal surgery. There is controversial data about efficacy of this adjuvant therapy in patients who have undergone D2 lymphadenectomy predominantly. In our hospital D2 lymphadenectomy is standard surgery for gastric cancer., Objective: To prove that chemo and radio therapy post gastrectomy and D2 linphadenectomy in patients' with gastric cancer is effective., Material and Methods: Retrospective study with gastric adenocarcinoma patients stage II to IV M0 who underwent curative resection at INEN (Instituto Nacional de Enfermedades Neoplasicas) Lima-Peru between 2001 and 2006. Standard treatment at institution is D2 lymphadenectomy. Chemo radiotherapy according to INT0116 was given like adjuvant therapy. Survivalcurves were calculated according to Kaplan-Meier method and compared with log-rank test., Results: 84 patients were included 60.7% male and 39.3% female. Mean age was 49.5 years old. The pathologic stages were T1-T2 (15.5%), T3- T4 (84.5%), N0-N1 (10.7%), N2-N3 (89.3%). D2 lymphadenectomy was performed in all patients. The 3-year DFS was 17% and 3-year overall survival was 23.9%. However when we analyzed by subgroups the overall survival, was in group N1 (66.7%) and in group N2 (58.9%) and N3 (18.3%) and 3 years DFS by subgroups were N1 (100%), N2 (51.9%) and N3 (16.3%)., Conclusions: Adjuvant chemo radiotherapy decreased risk of death and relapse to three years mainly in patients with node positive N1-N2, who underwent curative resection with D2 lymphadenectomy, but recurrence was most frequent in N3 node positive, maybe is necessary improve the chemotherapy in this group of patients for decrease the rate of relapse.

Objectives: To determine the antimicrobial potential of marine actinomycetes against drug-resistant pathogens represented by strains of methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecalis (VRE)., Materials and Methods: Strains of actinomycetes (29) isolated from marine sediment were evaluated by their characteristics in two culture media and by testing their inhibitory capacity by in vitro antagonism against multi-drug resistant (MDR) pathogenic bacteria for MRSA and VRE. Organic extracts of 3 selected actinomicetes were processed to determine the minimum inhibitory concentration (MIC) of the active compound., Results: Most isolated actinomycetes belong to a homogeneous group of write-gray actinomycetes with a good growth in Marine Agar. The inhibitory rates of the isolates were above 85% for both pathogens with inhibition zones greater than 69 and 78 mm in diameter for MRSA and VRE respectively. Dichloromethane extracts of 3 isolates (I-400A, B1-T61, M10-77) showed strong inhibitory activity of both pathogens, M10-77 being the highest actinomycete strain with antibiotic activity against methicillin-resistant S. aureus ATCC 43300 and vancomycin-resistant E. faecalis ATCC 51299 with a minimum inhibitory concentrations (MIC) of 7.9 and 31.7 μg/ml respectively. Phylogenetic analysis of M10-77 strain showed 99% similarity with the marine species Streptomyces erythrogriseus., Conclusions: Marine sediments of the central coast of Peru, are a source of actinomycetes strains showing high capacity to produce bioactive compounds able to inhibit pathogens classified as multi-drug-resistant such as methicillin-resistant S. aureus and vancomycin-resistant E. faecalis.

Prospective sampling activities of intertidal invertebrates in the Ancon Bay (Lima, Peru) were done in order to select marine bacteria producing antimicrobial substances. The study included the isolation of bacteria in marine agar, in vitro antimicrobial susceptibility testing and electronic microscopic observations. We report the isolation, phenotypical characterization and antimicrobial properties of 10 strains of marine bacteria including the genus Vibrio, Pseudomonas, and Flavobacterium, and the order Actinomycetae that inhibit human pathogens. The results indicate that the marine invertebrates would be sources of bacteria producing antibiotic substances.