Bacteriophages potentiate the effect of antibiotics by eradication of persister cells and killing of biofilm-forming cells.

Persister cells and biofilms are associated with chronic urinary infections which are more critical when generated by multi-drug resistant bacteria. In this context, joint administration of phages and antibiotics has been proposed as an alternative approach, since it may decrease the probability to generate resistant mutants to both agents. In this work, we exposed cultures of uropathogenic Escherichia coli conjunctly to antibiotics and phages. We determined that MLP2 combined with antibiotics eradicates persister cells. Similarly, MLP1 and MLP3 impact viability of biofilm-forming cells when administered with ampicillin. Our findings suggest a feasible prophylactic and therapeutic use of these non-transducing phages.

Mode of action of p-quinone derivatives with trypanocidal activity studied by experimental and in silico models.

Quinones are attractive pharmacological scaffolds for developing new agents for the treatment of different transmissible and non-transmissible human diseases due to their capacity to alter the cell redox homeostasis. The bioactivity and potential mode of action of 19 p-quinone derivatives fused to different aromatic rings (carbo or heterocycles) and harboring distinct substituents were investigated in infective Trypanosoma brucei brucei. All the compounds, except for a furanequinone (EC50=38 µM), proved to be similarly or even more potent (EC50 = 0.5-5.5 µM) than the clinical drug nifurtimox (EC50 = 5.3 µM). Three furanequinones and one thiazolequinone displayed a higher selectivity than nifurtimox. Two of these selective hits resulted potent inhibitors of T. cruzi proliferation (EC50=0.8-1.1 µM) but proved inactive against Leishmania infantum amastigotes. Most of the p-quinones induced a rapid and marked intracellular oxidation in T. b. brucei. DFT calculations on the oxidized quinone (Q), semiquinone (Q•-) and hydroquinone (QH2) suggest that all quinones have negative ΔG for the formation of Q•-. Qualitative and quantitative structure-activity relationship analyses in two or three dimensions of different electronic and biophysical descriptors of quinones and their corresponding bioactivities (killing potency and oxidative capacity) were performed. Charge distribution over the quinone ring carbons of Q and Q.- and the frontier orbitals energies of SUMO (Q.-) and LUMO (Q) correlate with their oxidative and trypanocidal activity. QSAR analysis also highlighted that both bromine substitution in the p-quinone ring and a bulky phenyl group attached to the furane and thiazole rings (which generates a negative charge due to the π electron system polarized by the nearby heteroatoms) are favorable for activity. By combining experimental and in silico procedures, this study disclosed important information about p-quinones that may help to rationally tune their electronic properties and biological activities.

Impacto de las posturas forzadas en los docentes odontólogos de la Universidad Regional Autónoma de Los Andes

Introducción: Muy poco se habla acerca de las malas posturas en la práctica clínica diaria y sus consecuencias en la salud de los profesionales odontólogos a corto y largo plazo, el ejercicio de esta profesión implica estar expuestos constantemente a presentar ciertos problemas de salud ocupacional. Objetivo: Determinar la frecuencia de las diferentes posturas que generan molestias corporales en relación con la especialidad y el análisis de los trastornos musculoesqueléticos y su asociación con los años de la profesión en docentes odontólogos de la Universidad Regional Autónoma de Los Andes. Método: La investigación fue de tipo observacional, transversal y descriptivo. Se aplicó una encuesta en enero de 2023 a un grupo de 46 profesionales de Odontología, determinada como una muestra de tipo intencional no probabilística de forma intencionada. Se consideró la prueba no paramétrica de Ji cuadrado de Pearson, que por la naturaleza de sus variables de tipo cualitativo probó posibles asociaciones entre las estas. Resultados: De todas las posibles asociaciones entre las variables, la que se mostró notablemente significativa correspondió al tiempo de profesión y las molestias principalmente detectadas en la parte baja de la espalda y cuello; lo que denotaría que a mayor tiempo tenga el ejercicio clínico, mayores serán las molestias detectadas como parte de posturas forzadas que adoptan los profesionales. Conclusiones: Se encontró asociación o relación significativa entre los años de profesión y los síntomas detectados en los profesionales de Odontología encuestados; lo que indica que a mayor tiempo en el ejercicio clínico pueden devenir mayores problemas a nivel ergonómico. Es importante considerar la aplicación de medidas interventoras para mejorar los aspectos de salud ocupacional, ergonomía e higiene postural.

Introduction: Very little is said about bad posture in daily clinical practice and its consequences on the health of dental professionals in the short and long term; the practice of this profession implies being constantly exposed to certain occupational health problems. Objective: To determine the frequency of the different postures that generate body discomfort in relation to the specialty and the analysis of musculoskeletal disorders and their association with the years of the profession in dental teachers at the Universidad Regional Autónoma de Los Andes. Method: The research was observational, transversal and descriptive. A survey was applied in January 2023 to a group of 46 dental professionals, determined as an intentional non-probabilistic sample. The non-parametric Pearson's Chi-square test was considered, which due to the nature of its qualitative variables tested possible associations between them. Results: Of all the possible associations between the variables, the one that was notably significant corresponded to the time of profession and the discomforts mainly detected in the lower back and neck; which would denote that the longer the clinical practice lasts, the greater the discomfort detected as part of forced postures adopted by professionals. Conclusions: A significant association or relationship was found between years of profession and the symptoms detected in the dental professionals surveyed; which indicates that the longer the time spent in clinical practice, the greater the potential for ergonomic problems. It is important to consider the application of intervention measures to improve aspects of occupational health, ergonomics and postural hygiene.

Introdução: Muito pouco se fala sobre a má postura na prática clínica diária e suas consequências na saúde dos profissionais de odontologia a curto e longo prazo; o exercício desta profissão implica estar constantemente exposto a determinados problemas de saúde ocupacional. Objetivo: Determinar a frequência das diferentes posturas que geram desconforto corporal em relação à especialidade e a análise dos distúrbios musculoesqueléticos e sua associação com os anos de profissão em professores de odontologia da Universidad Regional Autónoma de Los Andes. Método: A pesquisa foi observacional, transversal e descritiva. Uma pesquisa foi aplicada em janeiro de 2023 a um grupo de 46 profissionais de odontologia, determinado como uma amostra não probabilística intencional. Foi considerado o teste não paramétrico Qui-quadrado de Pearson, que pela natureza de suas variáveis qualitativas testou possíveis associações entre elas. Resultados: De todas as associações possíveis entre as variáveis, a que se mostrou significativamente significativa correspondeu ao tempo de profissão e aos desconfortos detectados principalmente na região lombar e pescoço; o que denotaria que quanto mais tempo dura a prática clínica, maior é o desconforto detectado nas posturas forçadas adotadas pelos profissionais. Conclusões: Foi encontrada associação ou relação significativa entre os anos de profissão e os sintomas detectados nos profissionais de odontologia pesquisados; o que indica que quanto maior o tempo gasto na prática clínica, maior o potencial para problemas ergonômicos. É importante considerar a aplicação de medidas de intervenção para melhorar aspectos de saúde ocupacional, ergonomia e higiene postural.

Effect of low-dose Piscirickettsia salmonis infection on haematological-biochemical blood parameters in Atlantic salmon (Salmo salar).

Piscirickettsia salmonis is the etiological agent of Piscirickettsiosis, a severe disease that affects Atlantic salmon (Salmo salar) farmed in Chile and many other areas (Norway, Scotland, Ireland, Canada and the USA). This study investigated the effects of low-dose P. salmonis infection (1 × 102 CFU/ml) on Atlantic salmon. In this study, we challenged fish with an isolated representative of the EM-90 genogroup via intraperitoneal injection for 42 days. Infected fish displayed decreased haematocrit and haemoglobin levels at day 13 post-infection, indicating erythropenia, haemolysis and haemodilution. Conversely, their white blood cell counts increased on days 13 and 21 post-infection. Additionally, their iron levels decreased from day 2 post-infection, indicating iron deficiency and an inability to retrieve stored iron before infection. Their magnesium levels also decreased at day 28 post-infection, possibly due to osmoregulatory problems. Also, we observed an increase in lactate dehydrogenase activity on days 5, 21, and 28 post-infection, suggesting early symptoms of hepatotoxicity. Later analyses determined a decrease in plasma glucose levels from day 2 post-infection. This may be attributed to the hypoxic conditions caused by P. salmonis, leading to an excess utilization of stored carbohydrates. Our results suggest that the blood parameters we studied are useful for monitoring the physiological status of Atlantic salmon infected with P. salmonis.

Phenoxy- and Phenylamino-Heterocyclic Quinones: Synthesis and Preliminary Anti-Pancreatic Cancer Activity.

The successful application of fragment-based drug discovery strategy for the efficient synthesis of phenoxy- or phenylamino-2-phenyl-benzofuran, -benzoxazole and -benzothiazole quinones is described. Interestingly, in the final step of the synthesis of the target compounds, unusual results were observed on the regiochemistry of the reaction of bromoquinones with phenol and aniline. A theoretical study was carried out for better understanding the factors that control the regiochemistry of these reactions. The substituted heterocyclic quinones were evaluated in vitro to determine their cytotoxicity by the MTT method in three pancreatic cancer cell lines (MIA-PaCa-2, BxPC-3, and AsPC-1). Phenoxy benzothiazole quinone 26a showed potent cytotoxic activity against BxPC-3 cell lines, while phenylamino benzoxazole quinone 20 was the most potent on MIA-PaCa-2 cells. Finally, electrochemical properties of these quinones were determined to correlate with a potential mechanism of action. All these results, indicate that the phenoxy quinone fragment led to compounds with increased activity against pancreatic cancer cells.

Isolation and Characterization of Novel Lytic Phages Infecting Multidrug-Resistant Escherichia coli.

Urinary tract infections (UTIs) are the second most frequent bacterial infections worldwide, with Escherichia coli being the main causative agent. The increase of antibiotic-resistance determinants among isolates from clinical samples, including UTIs, makes the development of novel therapeutic strategies a necessity. In this context, the use of bacteriophages as a therapeutic alternative has been proposed, due to their ability to efficiently kill bacteria. In this work, we isolated and characterized three novel bacteriophages, microbes laboratory phage 1 (MLP1), MLP2, and MLP3, belonging to the Chaseviridae, Myoviridae, and Podoviridae families, respectively. These phages efficiently infect and kill laboratory reference strains and multidrug-resistant clinical E. coli isolates from patients with diagnosed UTIs. Interestingly, these phages are also able to infect intestinal pathogenic Escherichia coli strains, such as enteroaggregative E. coli and diffusely adherent E. coli. Our data show that the MLP phages recognize different regions of the lipopolysaccharide (LPS) molecule, an important virulence factor in bacteria that is also highly variable among different E. coli strains. Altogether, our results suggest that these phages may represent an interesting alternative for the treatment of antibiotic-resistant E. coli. IMPORTANCE Urinary tract infections affect approximately 150 million people annually. The current antibiotic resistance crisis demands the development of novel therapeutic alternatives. Our results show that three novel phages, MLP1, MLP2, and MLP3 are able to infect both laboratory and multidrug-resistant clinical isolates of Escherichia coli. Since these phages (i) efficiently kill antibiotic-resistant clinical isolates of uropathogenic Escherichia coli (UPEC), (ii) recognize different portions of the LPS molecule, and (iii) are able to efficiently infect intestinal pathogenic Escherichia coli hosts, we believe that these novel phages are good candidates to be used as a therapeutic alternative to treat antibiotic-resistant E. coli strains generating urinary tract and/or intestinal infections.

Characterization and expression analysis of Nod-like receptor 3 (NLRC3) against infection with Piscirickettsia salmonis in Atlantic salmon.

The nucleotide binding oligomerization domain like receptors, or NOD like receptors (NLRs), are intracellular receptors responsible for recognizing pathogens in vertebrates. Several NLR mammalian models have been characterized and analyzed but few studies have been performed with teleost species. In this study, we analyzed the nucleotide sequence of six mRNA variants of NLRC3 in Atlantic salmon (SsNLRC3), and we deduced the amino acid sequence coding for two different isoforms with a total length of 1135 amino acids and 1093 amino acids. We analyzed the phylogeny of all variants, including a Piscirickettsia salmonis infection in Atlantic salmon. All variants and their expression pattern during infection were analyzed using real-time qPCR. One of the analyzed variants was over-expressed during the early stages of Piscirickettsia salmonis infection, and we were able to identify two different SsNLRC3 isoforms. Lastly, we observed that an alteration in the amino acid sequence of one of the isoforms can directly affect the pathogen recognition function.

Subcellular Location of Piscirickettsia salmonis Heat Shock Protein 60 (Hsp60) Chaperone by Using Immunogold Labeling and Proteomic Analysis.

Piscirickettsia salmonis is the causative bacterial agent of piscirickettsiosis, a systemic fish disease that significantly impacts the Chilean salmon industry. This bacterium possesses a type IV secretion system (T4SS), several proteins of the type III secretion system (T3SS), and a single heat shock protein 60 (Hsp60/GroEL). It has been suggested that due to its high antigenicity, the P. salmonis Hsp60 could be surface-exposed, translocated across the membrane, and (or) secreted into the extracellular matrix. This study tests the hypothesis that P. salmonis Hsp60 could be located on the bacterial surface. Immunogold electron microscopy and proteomic analyses suggested that although P. salmonis Hsp60 was predominantly associated with the bacterial cell cytoplasm, Hsp60-positive spots also exist on the bacterial cell envelope. IgY antibodies against P. salmonis Hsp60 protected SHK-1 cells against infection. Several bioinformatics approaches were used to assess Hsp60 translocation by the T4SS, T3SS, and T6SS, with negative results. These data support the hypothesis that small amounts of Hsp60 must reach the bacterial cell surface in a manner probably not mediated by currently characterized secretion systems, and that they remain biologically active during P. salmonis infection, possibly mediating adherence and (or) invasion.

Porphyromonas gingivalis and its impact on periodontal health and systemic diseases: a concise review

Periodontitis is defined as a multifactorial chronic inflammatory disease, associated to a dys-biotic biofilm and characterized by the progressive destruction of the periodontal attachment. Clinical studies have revealed the presence of 10 to 15 bacterial species that are potential periodontal pathogens in adults. From these, the most cited are Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans and Tannerella forsythia. The aim of this article is to review P. gingivalis' characteristics and impact on periodontal and systemic health. Different studies have reported a relation between the presence of P. gingivalis and periodontal disea-se. P. gingivalis was one of the most frequently detected species in aggressive and chronic periodontitis. This is due to its unique ability to avoid the host's immune response and con-tribute to the development of the destructive process. P. gingivalis, although only present in low frequency, is pathogenic because of its ability to induce dysbiotic microbial communities. There is more evidence that P. gingivalis might invade cardiovascular cells and tissues causing inflammation. It has been suggested that NLRP3 inflammasome plays a key role in the deve-lopment of vascular inflammation and atherosclerosis. The repeated exposure to P. gingiva-lis, produces neuroinflammation, neurodegeneration and formation of intra and extracellular amyloid plaques, which are pathognomonic signs of Alzheimer's disease

In vitro genomic and proteomic evidence of a type IV pili-like structure in the fish pathogen Piscirickettsia salmonis.

Piscirickettsia salmonis is an intracellular γ-proteobacteria and the etiological agent of piscirickettsiosis, which causes massive economic losses in the Chilean salmon industry. The type IV pili (T4P) play an important role in adherence to host cell surfaces and bacterial pathogenicity. T4P contains a variable number of components, as predicted in P. salmonis genomes. However, no studies have determined if P. salmonis possesses T4P. The aims of this investigation were to identify T4P components in the P. salmonis type strain LF-89T, evaluate respective transcript expressions, and analyze the main putative T4P proteins using bioinformatics and proteomic approaches. Two main clusters of P. salmonis T4P genes were found. Expression of the pilA gene was upregulated at 4 h post-infection (hpi), while pilQ was upregulated 4 days post-infection. At 16 hpi, pilB and pilD were strongly upregulated. The PilA amino acid sequence analysis showed a conserved N-terminal domain and sequence motifs critical for T4P biosynthesis. MudPIT analysis revealed PilA in the P. salmonis LF-89T proteome, and TEM showed pili-like filamentous structures on the P. salmonis surface. These results strongly suggest the presence of a T4P-like structure in P. salmonis.

Comparative Pan-Genome Analysis of Piscirickettsia salmonis Reveals Genomic Divergences within Genogroups.

Piscirickettsia salmonis is the etiological agent of salmonid rickettsial septicemia, a disease that seriously affects the salmonid industry. Despite efforts to genomically characterize P. salmonis, functional information on the life cycle, pathogenesis mechanisms, diagnosis, treatment, and control of this fish pathogen remain lacking. To address this knowledge gap, the present study conducted an in silico pan-genome analysis of 19 P. salmonis strains from distinct geographic locations and genogroups. Results revealed an expected open pan-genome of 3,463 genes and a core-genome of 1,732 genes. Two marked genogroups were identified, as confirmed by phylogenetic and phylogenomic relationships to the LF-89 and EM-90 reference strains, as well as by assessments of genomic structures. Different structural configurations were found for the six identified copies of the ribosomal operon in the P. salmonis genome, indicating translocation throughout the genetic material. Chromosomal divergences in genomic localization and quantity of genetic cassettes were also found for the Dot/Icm type IVB secretion system. To determine divergences between core-genomes, additional pan-genome descriptions were compiled for the so-termed LF and EM genogroups. Open pan-genomes composed of 2,924 and 2,778 genes and core-genomes composed of 2,170 and 2,228 genes were respectively found for the LF and EM genogroups. The core-genomes were functionally annotated using the Gene Ontology, KEGG, and Virulence Factor databases, revealing the presence of several shared groups of genes related to basic function of intracellular survival and bacterial pathogenesis. Additionally, the specific pan-genomes for the LF and EM genogroups were defined, resulting in the identification of 148 and 273 exclusive proteins, respectively. Notably, specific virulence factors linked to adherence, colonization, invasion factors, and endotoxins were established. The obtained data suggest that these genes could be directly associated with inter-genogroup differences in pathogenesis and host-pathogen interactions, information that could be useful in designing novel strategies for diagnosing and controlling P. salmonis infection.

The Proteome of Biologically Active Membrane Vesicles from Piscirickettsia salmonis LF-89 Type Strain Identifies Plasmid-Encoded Putative Toxins.

Piscirickettsia salmonis is the predominant bacterial pathogen affecting the Chilean salmonid industry. This bacterium is the etiological agent of piscirickettsiosis, a significant fish disease. Membrane vesicles (MVs) released by P. salmonis deliver several virulence factors to host cells. To improve on existing knowledge for the pathogenicity-associated functions of P. salmonis MVs, we studied the proteome of purified MVs from the P. salmonis LF-89 type strain using multidimensional protein identification technology. Initially, the cytotoxicity of different MV concentration purified from P. salmonis LF-89 was confirmed in an in vivo adult zebrafish infection model. The cumulative mortality of zebrafish injected with MVs showed a dose-dependent pattern. Analyses identified 452 proteins of different subcellular origins; most of them were associated with the cytoplasmic compartment and were mainly related to key functions for pathogen survival. Interestingly, previously unidentified putative virulence-related proteins were identified in P. salmonis MVs, such as outer membrane porin F and hemolysin. Additionally, five amino acid sequences corresponding to the Bordetella pertussis toxin subunit 1 and two amino acid sequences corresponding to the heat-labile enterotoxin alpha chain of Escherichia coli were located in the P. salmonis MV proteome. Curiously, these putative toxins were located in a plasmid region of P. salmonis LF-89. Based on the identified proteins, we propose that the protein composition of P. salmonis LF-89 MVs could reflect total protein characteristics of this P. salmonis type strain.

In vitro expression of Sec-dependent pathway and type 4B secretion system in Piscirickettsia salmonis.

Piscirickettsia salmonis is an intracellular bacterium and the causative agent of Piscirickettsiosis, a disease responsible for considerable mortalities in the Chilean salmon farming industry. Currently, P. salmonis protein translocation across the membrane and the mechanisms by which virulence factors are delivered to host cells are poorly understood. However, it is known that Gram-negative bacteria possess several mechanisms that transport proteins to the periplasmic and extracellular compartments. The aim of this study was to evaluate the expressional changes of several genes in the P. salmonis Sec-dependent pathway and type 4B secretion system during in vitro infection. Genes homologous and the main proteins belonging to Sec-dependent pathway and Type 4 Dot/Icm secretion system were found in the genome and proteome of P. salmonis AUSTRAL-005 strain. Additionally, several genes of these protein transport mechanisms were overexpressed during in vitro P. salmonis infection in SHK-1 cell line. The obtained data indicate that the Sec-dependent pathway and Type 4B secretion system are biologically active during P. salmonis infection. These mechanisms could contribute to the recycling of proteins into the inner and outer bacterial membrane and in translocate virulence factors to infected cell, which would favor the structural integrity and virulence of this bacterium.

Identification of chemotaxis operon cheYZA and cheA gene expression under stressful conditions in Piscirickettsia salmonis.

Piscirickettsia salmonis is the etiological agent of piscirickettsiosis, which, as the main systemic disease in the Chilean salmon industry, causes significant economic losses. This bacterium can produce biofilm as a persistence and survival strategy in adverse conditions. In other bacteria, cheA is a key gene for modulating the onset of bacterial chemotaxis, as well as having a secondary role in biofilm production. Notwithstanding this association, the potential relationships between biofilm formation and genes involved in P. salmonis chemotaxis are poorly understood. This study aimed to determine P. salmonis cheA gene expression when grown in different culture media known to induce biofilm production. Piscirickettsia salmonis AUSTRAL-005 produced moderate/high biofilm levels after 144 h of incubation in the AUSTRAL-SRS and marine broths. In contrast, LF-89 biofilm production was weak/nonexistent in the aforementioned broths. Both assessed P. salmonis strains contained the cheYZA operon. Additionally, AUSTRAL-005 cheA transcripts increased in both culture media. In conclusion, these results suggest potential relationships between biofilm formation and genes related to chemotaxis in the fish pathogen P. salmonis.

Morphological characteristics of Street Workout practitioners.

INTRODUCTION: The determination of the morphological characteristics of the most popular sports has allowed the evaluation and comparison between athletes, which has helped to improve their performance. The Street Workout is an emerging sport based on calisthenics, which recently has become popular. Despite its popularization, neither the morphologic profile nor the morphologic characteristics of Street Workout athletes has been determined. OBJECTIVE: Determine the profile and morphological characteristics of Street-Workout athletes, through anthropometry. MATERIAL AND METHODS: Fourteen athletes (22.7 ± 3.26 years) were recruited from the National Calisthenics Tournament 2015 in Chile. The athletes were evaluated following the protocol of the International Society for the Advancement of Kinanthropometry to determine the somatotype, body composition, as well as indices of body composition such as body mass index, waist to hip ratio, waist to height ratio, fat/muscle mass and muscle/bone mass indexes. RESULTS: Street Workout practitioners presented a balanced-mesomorphic somatotype, a low fat mass and a high muscular development, with upper arms and trunk predominance. Regarding body composition indices, the values obtained allow us to classify them as a low-risk population of chronic non-communicable diseases. CONCLUSION: The present study sets a first antecedent of the morphological characteristics of Street Workout, determining that the Street Workout athletes presented balanced-mesomorphic somatotype and were classified as a healthy and athletic sample by their body composition indexes.

Morphological characteristics of Street Workout practitioners / Características morfológicas de practicantes de Street Workout

Introduction: The determination of the morphological characteristics of the most popular sports has allowed the evaluation and comparison between athletes, which has helped to improve their performance. The Street Workout is an emerging sport based on calisthenics, which recently has become popular. Despite its popularization, neither the morphologic profile nor the morphologic characteristics of Street Workout athletes has been determined. Objective: Determine the profile and morphological characteristics of Street-Workout athletes, through anthropometry. Material and methods: Fourteen athletes (22.7 ± 3.26 years) were recruited from the National Calisthenics Tournament 2015 in Chile. The athletes were evaluated following the protocol of the International Society for the Advancement of Kinanthropometry to determine the somatotype, body composition, as well as indices of body composition such as body mass index, waist to hip ratio, waist to height ratio, fat/muscle mass and muscle/bone mass indexes. Results: Street Workout practitioners presented a balanced-mesomorphic somatotype, a low fat mass and a high muscular development, with upper arms and trunk predominance. Regarding body composition indices, the values obtained allow us to classify them as a low-risk population of chronic non-communicable diseases. Conclusion: The present study sets a first antecedent of the morphological characteristics of Street Workout, determining that the Street Workout athletes presented balanced-mesomorphic somatotype and were classified as a healthy and athletic sample by their body composition indexes (AU)

Introducción: la determinación de las características morfológicas de los deportes más populares ha permitido la evaluación y comparación entre los atletas, lo que ha contribuido a mejorar su rendimiento. El street workout (ejercicio callejero) es un deporte emergente basado en ejercicios de calistenia, el cual ha ido ganando popularidad en los últimos años. A pesar de su masificación, aún no ha sido determinado el perfil morfológico ni las características morfológicas de los atletas de street workout. Objetivo: determinar las características y el perfil morfológico de los atletas de street workout mediante antropometría. Material y métodos: catorce atletas (22,7 ± 3,26 años de edad promedio) fueron reclutados del Torneo Nacional de Calistenia del año 2015 en Chile. Los atletas fueron evaluados siguiendo el protocolo de la Sociedad Internacional para el Avance de la Kineantropometría para determinar el somatotipo, la composición corporal, así como también índices de composición corporal tales como el índice de masa corporal, cintura/cadera, cintura/talla masa grasa/músculo y músculo/masa ósea. Resultados: los atletas de street workout evaluados presentaron un somatotipo mesomórfico balanceado, una baja masa grasa y un alto desarrollo muscular, con dominancia en miembros superiores y tronco. Respecto a los índices de composición corporal, los valores obtenidos permiten clasificar a este grupo de atletas como una población de bajo riesgo de enfermedades crónicas no transmisibles. Conclusión: el presente estudio sienta el primer antecedente de las características morfológicas del street workout, estableciendo que los atletas evaluados presentan un somatotipo mesomórfico equilibrado, siendo clasificados como una muestra atlética y saludable por sus índices de composición corporal (AU)

Identification and expressional analysis of NLRC5 inflammasome gene in smolting Atlantic salmon (Salmo salar).

The NOD-like receptors (NLRs) were recently identified as an intracellular pathogen recognition receptor family in vertebrates. While the immune system participation of NLRs has been characterized and analyzed in various mammalian models, few studies have considered NLRs in teleost species. Therefore, this study analyzed the Atlantic salmon (Salmo salar) NLRC5. Structurally, Atlantic salmon NLRC5 presented leucine-rich repeat subfamily genes. Phylogenetically, NLRC5 was moderately conserved between S. salar and other species. Real-time quantitative PCR revealed NLRC5 expression in almost all analyzed organs, with greatest expressions in the head kidney, spleen, and hindgut. Furthermore, NLRC5 gene expression decreased during smolt stage. These data suggest that NLRC5 participates in the Atlantic salmon immune response and is regulated, at least partly, by the smoltification process, suggesting that there is a depression of immune system from parr at smolt stage. This is the first report on the NLRC5 gene in salmonid smolts.

Resistance-nodulation-division efflux pump acrAB is modulated by florfenicol and contributes to drug resistance in the fish pathogen Piscirickettsia salmonis.

Piscirickettsia salmonis is a fastidious intracellular pathogen responsible for high mortality rates in farmed salmonids, with serious economic consequences for the Chilean aquaculture industry. Oxytetracycline and florfenicol are the most frequently used antibiotics against P. salmonis, but routine use could contribute to drug resistance. This study identified differentiated florfenicol susceptibilities in two P. salmonis strains, LF-89 and AUSTRAL-005. The less susceptible isolate, AUSTRAL-005, also showed a high ethidium bromide efflux rate, indicating a higher activity of general efflux pump genes than LF-89. The P. salmonis genome presented resistance nodulation division (RND) family members, a family containing typical multidrug resistance-related efflux pumps in Gram-negative bacteria. Additionally, efflux pump acrAB genes were overexpressed in AUSTRAL-005 following exposure to the tolerated maximal concentration of florfenicol, in contrast to LF-89. These results indicate that tolerated maximum concentrations of florfenicol can modulate RND gene expression and increase efflux pump activity. We propose that the acrAB efflux pump is essential for P. salmonis survival at critical florfenicol concentrations and for the generation of antibiotic-resistant bacterial strains.

Somatotipo y composición corporal de la selección de fútbol masculino universitario de Chile, Pontificia Universidad Católica de Valparaíso, campeona los años 2012 y 2013 / Somatotype and body composition of the male university soccer team at Pontificia Universidad Católica de Valparaíso, champions 2012-2013

El objetivo del presente estudio es determinar el somatotipo y la composición corporal de la selección masculina de fútbol universitario bicampeona del año 2013 y realizar la comparación de éstos entre posiciones de juego y con otras poblaciones de futbolistas. Se realizó una evaluación kineantropométrica a trece jugadores de la selección masculina de fútbol de la Pontificia Universidad Católica de Valparaíso (PUCV) 2013, utilizando el perfil completo del protocolo de la Sociedad Internacional para el Avance de la Kineantropometría (ISAK). Las mediciones se realizaron en pretemporada. Se determinó que el somatotipo de la selección masculina de fútbol de la PUCV 2013 corresponde a Endo-Mesomorfo (3,5­5,6­1,7). Los valores de composición corporal promedio de la selección de fútbol PUCV fueron 25,81% de masa grasa, 47,41% de masa muscular, 10,68% de masa ósea, 5,07% de masa piel y 11,03% de masa residual. No se encontraron diferencias significativas en los resultados expuestos en las diferentes posiciones en el campo de juego, con respecto a somatotipo, composición corporal y variables kineantropométricas analizadas (valor p >0,05). El perfil somatotípico de la selección masculina de fútbol de la PUCV 2013 es Endo-Mesomorfo, resultado similar al encontrado en otro estudio realizado en futbolistas universitarios. En cuanto a la composición corporal se observó que los porcentajes de tejido muscular y óseo se encuentran dentro de los rangos aceptables, mientras que el tejido graso se encuentra elevado respecto a otras poblaciones de futbolistas profesionales y universitarios.

The objective of this study was to determine the somatotype and body composition of the male university soccer team at Pontificia Universidad Católica de Valparaíso (PUCV) and then compare them, according to playing positions and other soccer populations. Thirteen players of the university soccer team at PUCV underwent a kineanthropometric evaluation, using the full profile of the International Society for the Advancement of Kinanthropometry (ISAK) protocol. The measures were performed in the 2013 pre-season. The somatotype of the male soccer team at PUCV corresponds to endomorphic-mesomorph (3.5­5.6­1.7). The average values of the body composition of the soccer team were 25.81% of fat mass, 47.41% of muscle mass, 10.68% of bone mass, 5.07% of skin mass and 11.03% of residual mass. No significant differences were observed among different playing positions with respect to the somatotype, for either body composition or any kineanthropometric variables analyze (p value >0.05). The somatotypical profile of the male university soccer team at PUCV is endo-mesomorphic, which is in accordance to a similar study conducted on university soccer players in Mexico. According to body composition, it was observed that the percentages of muscle and bone mass are in the acceptable ranges, while fat mass is elevated compared to other professional populations as well as other university soccer players.

Elección del modelo de proporcionalidad antropométrica en una población deportista; comparación de tres métodos / Anthropometric proportionality method election in a sport population; comparison of three methods

Introducción: la aplicación de modelos de proporcionalidad, basados en proporciones ideales, tendría un gran impacto en el deporte de alto rendimiento, debido a que los mejores deportistas tienden a asemejarse antropométricamente. Objetivo: el objetivo de este estudio es comparar los métodos de proporcionalidad antropométrica: Phantom, Combinado y Escalable, en los campeones chilenos de fútbol masculino universitario de los años 2012 y 2013, ocupando como población de criterio a futbolistas profesionales sudamericanos, con el fin de encontrar el método de proporcionalidad más adecuado para poblaciones de deportistas. Metodología: se realizó la evaluación de 22 variables kineantropométricas, según el protocolo ISAK, a una muestra constituida por 13 jugadores pertenecientes a la selección masculina de fútbol de la Pontificia Universidad Católica de Valparaíso. Se obtuvieron los valores Z de cada variable antropométrica de los diferentes métodos, usando sus fórmulas respectivas. Se usó como población de criterio a los futbolistas profesionales sudamericanos. Resultados: se observó una tendencia semejante entre los tres métodos. Se encontraron diferencias significativas (p < 0,05) en los valores Z de los métodos Escalable y Combinado, respecto al método Phantom. No se encontraron diferencias significativas entre los resultados obtenidos por los métodos Combinado y Escalable, excepto en los perímetros radiocarpiano, cadera y muslo. Conclusión: se propone la utilización del método Escalable sobre el método Combinado y Phantom para realizar la comparación de valores Z en variables kineantropométricas en deportistas de la misma disciplina (AU)

Introduction: the proportionality model application, based on ideal proportions, would have a great impact on high performance sports, due to best athletes to resemble anthropometrically. Objective: the objective of this study was to compare the following anthropometric methods of proportionality: Phantom, Combined and Scalable, in male champion university Chilean soccer players in 2012 and 2013, using South American professional soccer players as criterion, in order to find the most appropriate proportionality method to sports populations. Method: the measerement of 22 kinanthropometric variables was performed, according to the ISAK protocol, to a sample constituted of 13 members of the men’s soccer team of the Pontificia Universidad Católica de Valparaíso. The Z-values of the anthropometrics variables of each method were obtained using their respective equations. It was used as criterion population South American soccer players. Results: a similar trend was observed between the three methods. Significant differences (p <0.05) were found in some Z-values of Scalable and Combined methods compared to Phantom method. No significant differences were observed between the results obtained by the Combined and Scalable methods, except in wrist, thigh and hip perimeters. Conclusion: it is more appropriate to use the Scalable method over the Combined and Phantom methods for the comparison of Z values in kinanthropometric variables in athletes of the same discipline (AU)