4to. Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad. Memoria académica

Este volumen acoge la memoria académica de la Cuarta edición del Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad, CITIS 2017, desarrollado entre el 29 de noviembre y el 1 de diciembre de 2017 y organizado por la Universidad Politécnica Salesiana (UPS) en su sede de Guayaquil. El Congreso ofreció un espacio para la presentación, difusión e intercambio de importantes investigaciones nacionales e internacionales ante la comunidad universitaria que se dio cita en el encuentro. El uso de herramientas tecnológicas para la gestión de los trabajos de investigación como la plataforma Open Conference Systems y la web de presentación del Congreso http://citis.blog.ups.edu.ec/, hicieron de CITIS 2017 un verdadero referente entre los congresos que se desarrollaron en el país. La preocupación de nuestra Universidad, de presentar espacios que ayuden a generar nuevos y mejores cambios en la dimensión humana y social de nuestro entorno, hace que se persiga en cada edición del evento la presentación de trabajos con calidad creciente en cuanto a su producción científica. Quienes estuvimos al frente de la organización, dejamos plasmado en estas memorias académicas el intenso y prolífico trabajo de los días de realización del Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad al alcance de todos y todas

Assessment of Murine Colon Inflammation Using Intraluminal Fluorescence Lifetime Imaging.

Inflammatory bowel disease (IBD) is typically diagnosed by exclusion years after its onset. Current diagnostic methods are indirect, destructive, or target overt disease. Screening strategies that can detect low-grade inflammation in the colon would improve patient prognosis and alleviate associated healthcare costs. Here, we test the feasibility of fluorescence lifetime imaging (FLIm) to detect inflammation from thick tissue in a non-destructive and label-free approach based on tissue autofluorescence. A pulse sampling FLIm instrument with 355 nm excitation was coupled to a rotating side-viewing endoscopic probe for high speed (10 mm/s) intraluminal imaging of the entire mucosal surface (50-80 mm) of freshly excised mice colons. Current results demonstrate that tissue autofluorescence lifetime was sensitive to the colon anatomy and the colonocyte layer. Moreover, mice under DSS-induced colitis and 5-ASA treatments showed changes in lifetime values that were qualitatively related to inflammatory markers consistent with alterations in epithelial bioenergetics (switch between β-oxidation and aerobic glycolysis) and physical structure (colon length). This study demonstrates the ability of intraluminal FLIm to image mucosal lifetime changes in response to inflammatory treatments and supports the development of FLIm as an in vivo imaging technique for monitoring the onset, progression, and treatment of inflammatory diseases

Assessment of Murine Colon Inflammation Using Intraluminal Fluorescence Lifetime Imaging

Inflammatory bowel disease (IBD) is typically diagnosed by exclusion years after its onset. Current diagnostic methods are indirect, destructive, or target overt disease. Screening strategies that can detect low-grade inflammation in the colon would improve patient prognosis and alleviate associated healthcare costs. Here, we test the feasibility of fluorescence lifetime imaging (FLIm) to detect inflammation from thick tissue in a non-destructive and label-free approach based on tissue autofluorescence. A pulse sampling FLIm instrument with 355 nm excitation was coupled to a rotating side-viewing endoscopic probe for high speed (10 mm/s) intraluminal imaging of the entire mucosal surface (50–80 mm) of freshly excised mice colons. Current results demonstrate that tissue autofluorescence lifetime was sensitive to the colon anatomy and the colonocyte layer. Moreover, mice under DSS-induced colitis and 5-ASA treatments showed changes in lifetime values that were qualitatively related to inflammatory markers consistent with alterations in epithelial bioenergetics (switch between β-oxidation and aerobic glycolysis) and physical structure (colon length). This study demonstrates the ability of intraluminal FLIm to image mucosal lifetime changes in response to inflammatory treatments and supports the development of FLIm as an in vivo imaging technique for monitoring the onset, progression, and treatment of inflammatory diseases

Concordance of ompA types in children re-infected with ocular Chlamydia trachomatis following mass azithromycin treatment for trachoma.

BackgroundThe chlamydial major outer membrane protein, encoded by the ompA gene, is a primary target for chlamydial vaccine research. However, human studies of ompA-specific immunity are limited, and prior studies have been limited in differentiating re-infection from persistent infection. The purpose of this study was to assess whether children living in trachoma-endemic communities with re-infections of ocular chlamydia were more likely to be infected with a different or similar genovar.Methodology and findingsThe study included 21 communities from a trachoma-hyperendemic area of Ethiopia that had been treated with a mass azithromycin distribution for trachoma. Conjunctival swabbing was offered to all children younger than 5 years of age at baseline (i.e., pre-treatment), and then at follow-up visits 2 and 6 months later. Swabs were subjected to polymerase chain reaction (PCR) to detect C. trachomatis. A random sample of 359 PCR-positive swabs, stratified by study visit and study community, was chosen for ompA sequencing. In addition, ompA sequencing was performed on all swabs of 24 children who experienced chlamydial re-infection (i.e., positive chlamydial test before treatment, negative test 2 months following mass distribution of azithromycin, and again a positive test 6 months post-treatment). ompA sequencing was successful for 351 of 359 swabs of the random sample and 44 of 48 swabs of the re-infection sample. In the random sample, ompA types clustered within households more than would be expected by chance. Among the 21 re-infected children with complete ompA data, 14 had the same ompA type before and after treatment.ConclusionThe high frequency of ompA concordance suggests incomplete genovar-specific protective immunity and the need for multiple antigens as vaccine targets

Increased Epithelial Oxygenation Links Colitis to an Expansion of Tumorigenic Bacteria

Intestinal inflammation is a risk factor for colorectal cancer formation, but the underlying mechanisms remain unknown. Here, we investigated whether colitis alters the colonic microbiota to enhance its cancer-inducing activity. Colitis increased epithelial oxygenation in the colon of mice and drove an expansion of Escherichia coli within the gut-associated microbial community through aerobic respiration. An aerobic expansion of colibactin-producing E. coli was required for the cancer-inducing activity of this pathobiont in a mouse model of colitis-associated colorectal cancer formation. We conclude that increased epithelial oxygenation in the colon is associated with an expansion of a prooncogenic driver species, thereby increasing the cancer-inducing activity of the microbiota.IMPORTANCE One of the environmental factors important for colorectal cancer formation is the gut microbiota, but the habitat filters that control its cancer-inducing activity remain unknown. Here, we show that chemically induced colitis elevates epithelial oxygenation in the colon, thereby driving an expansion of colibactin-producing Escherichia coli, a prooncogenic driver species. These data suggest that elevated epithelial oxygenation is a potential risk factor for colorectal cancer formation because the consequent changes in the gut habitat escalate the cancer-inducing activity of the microbiota

Increased Epithelial Oxygenation Links Colitis to an Expansion of Tumorigenic Bacteria

One of the environmental factors important for colorectal cancer formation is the gut microbiota, but the habitat filters that control its cancer-inducing activity remain unknown. Here, we show that chemically induced colitis elevates epithelial oxygenation in the colon, thereby driving an expansion of colibactin-producing Escherichia coli, a prooncogenic driver species. These data suggest that elevated epithelial oxygenation is a potential risk factor for colorectal cancer formation because the consequent changes in the gut habitat escalate the cancer-inducing activity of the microbiota.Intestinal inflammation is a risk factor for colorectal cancer formation, but the underlying mechanisms remain unknown. Here, we investigated whether colitis alters the colonic microbiota to enhance its cancer-inducing activity. Colitis increased epithelial oxygenation in the colon of mice and drove an expansion of Escherichia coli within the gut-associated microbial community through aerobic respiration. An aerobic expansion of colibactin-producing E. coli was required for the cancer-inducing activity of this pathobiont in a mouse model of colitis-associated colorectal cancer formation. We conclude that increased epithelial oxygenation in the colon is associated with an expansion of a prooncogenic driver species, thereby increasing the cancer-inducing activity of the microbiota

Diversity of Chlamydia trachomatis in Trachoma-Hyperendemic Communities Treated With Azithromycin.

Prior studies have theorized that low chlamydial genetic diversity following mass azithromycin treatments for trachoma may create a population bottleneck that prevents the return of infection, but little empirical evidence exists to support this hypothesis. In this study, a single mass azithromycin distribution was administered to 21 communities in the Gurage Zone of Ethiopia in 2003. All children aged 1-5 years had conjunctival swabs performed before treatment and 2 and 6 months after treatment. All swabs positive for Chlamydia trachomatis at 2 months underwent typing of the gene encoding the major outer membrane protein (ompA) of C. trachomatis, as did the same number of swabs per community from the pretreatment and 6-month visits. Diversity of ompA types, expressed as the reciprocal of Simpson's index, was calculated for each community. In total, 15 ompA types belonging to the A and B genovars were identified. The mean diversity was 2.11 (95% confidence interval: 1.79, 2.43) before treatment and 2.16 (95% confidence interval: 1.76, 2.55) 2 months after treatment (P = 0.78, paired t test). Diversity of ompA was not associated with the prevalence of ocular chlamydia (P = 0.76) and did not predict subsequent changes in the prevalence of ocular chlamydia (P = 0.32). This study found no evidence to support the theory that ompA diversity is associated with transmission of ocular chlamydia

BackMov: individualized motion capture-based test to assess low back pain mobility recovery after treatment

Low back pain (LBP) is a common issue that negatively affects a person’s quality of life and imposes substantial healthcare expenses. In this study, we introduce the (Back-pain Movement) BackMov test, using inertial motion capture (MoCap) to assess lumbar movement changes in LBP patients. The test includes flexion–extension, rotation, and lateralization movements focused on the lumbar spine. To validate its reproducibility, we conducted a test-retest involving 37 healthy volunteers, yielding results to build a minimal detectable change (MDC) graph map that would allow us to see if changes in certain variables of LBP patients are significant in relation to their recovery. Subsequently, we evaluated its applicability by having 30 LBP patients perform the movement’s test before and after treatment (15 received deep oscillation therapy; 15 underwent conventional therapy) and compared the outcomes with a specialist’s evaluations. The test-retest results demonstrated high reproducibility, especially in variables such as range of motion, flexion and extension ranges, as well as velocities of lumbar movements, which stand as the more important variables that are correlated with LBP disability, thus changes in them may be important for patient recovery. Among the 30 patients, the specialist’s evaluations were confirmed using a low-back-specific Short Form (SF)-36 Physical Functioning scale, and agreement was observed, in which all patients improved their well-being after both treatments. The results from the specialist analysis coincided with changes exceeding MDC values in the expected variables. In conclusion, the BackMov test offers sensitive variables for tracking mobility recovery from LBP, enabling objective assessments of improvement. This test has the potential to enhance decision-making and personalized patient monitoring in LBP management

Vitamin A supplementation boosts control of antibiotic-resistant Salmonella infection in malnourished mice.

Disseminated disease from non-typhoidal Salmonella enterica strains results in >20% mortality globally. Barriers to effective treatment include emerging multidrug resistance, antibiotic treatment failure, and risk factors such as malnutrition and related micronutrient deficiencies. Individuals in sub-Saharan Africa are disproportionately affected by non-typhoidal S. enterica bloodstream infections. To inform a clinical trial in people, we investigated vitamin A as a treatment in the context of antibiotic treatment failure in a mouse model of vitamin A deficiency. Vitamin A-deficient (VAD) mice exhibited higher systemic bacterial levels with a multidrug-resistant clinical isolate in comparison to mice on a control diet. Sex-specific differences in vitamin A deficiency and disseminated infection with S. enterica serotype Typhimurium (S. Typhimurium) were observed. VAD male mice had decreased weight gain compared to control male mice. Further, infected VAD male mice had significant weight loss and decreased survival during the course of infection. These differences were not apparent in female mice. In a model of disseminated S. Typhimurium infection and antibiotic treatment failure, we assessed the potential of two consecutive doses of vitamin A in alleviating infection in male and female mice on a VAD or control diet. We found that subtherapeutic antibiotic treatment synergized with vitamin A treatment in infected VAD male mice, significantly decreasing systemic bacterial levels, mitigating weight loss and improving survival. These results suggest that assessing vitamin A as a therapy during bacteremia in malnourished patients may lead to improved health outcomes in a subset of patients, especially in the context of antibiotic treatment failure