Simple and promising paper-based electrochemical platform for serological detection of American tegumentary leishmaniasis

BACKGROUND American tegumentary leishmaniasis (ATL) is an endemic neglected tropical disease (NTD), its conventional treatment is toxic, slow, and invasive. Rapid diagnosis is crucial for the clinical management of suspected patients, so the development and use of low-cost, miniaturised and portable devices could be the key. OBJECTIVES This work aimed to develop a simple paper-based electrochemical platform for the serological detection of ATL. METHODS Platform was fabricated in Whatman N°1 paper, contains a hydrophobic zone generated by wax printing, two pencil graphite electrodes, and uses specific crude extracts (CA) antigens for ATL immuno-determination. The platform performance was analysed by measuring the relative impedance change for different antigen-antibody combinations. Then, 10 serum human samples previously diagnosed by the gold standard (five positive ATL cases and five non-ATL cases) were evaluated. FINDINGS The platform presented a linear response for the charge transfer resistance (ΔRct) and the interface reactance (ΔXc). Also, optimal working conditions were established (1/60 serum dilution and 180 µg/mL CA concentration). Then, the platform permits to distinguish between ATL and non-ATL (p < 0.05) human serum samples. MAIN CONCLUSIONS Our platform could allow the diagnosis, management, and monitoring of leishmaniasis while being an extremely simple and environmentally friendly technology.

Presentación atípica de tumor glómico en vía aérea: reporte de caso y revisión de literatura / Atypical presentation of glomus tumor in the airway: Case report and literature review

Introducción. Los tumores glómicos provienen de los cuerpos glómicos, que son estructuras con función de termorregulación y se encuentran distribuidas por todo el cuerpo humano, principalmente a nivel distal de las extremidades, donde es común encontrar lesiones características, aunque hay reportes de casos que se presentaron como neoformación en localizaciones más inusuales. Su etiología aun es desconocida. No se sospechan en muchos pacientes y el diagnostico se realiza de manera incidental, por estudios imagenológicos o anatomopatológicos. Caso clínico. Paciente femenina de 66 años, con presencia de tumor glómico en vía aérea, diagnosticado por histopatología e inmunohistoquímica, que fue sometido a resección quirúrgica, con buena evolución posterior. Discusión. Esta presentación atípica de tumor glómico en vía aérea se manifiesta principalmente con síntomas y signos relacionados con obstrucción de la vía aérea. El manejo oportuno es primordial y el diagnóstico definitivo es por histopatología e inmunohistoquímica, donde se observan las características de las células glómicas, estructuras vasculares, músculo liso y la positividad en la inmunotinción de marcadores como actina del músculo liso, CD34, y actina específica del músculo, entre otras. Conclusión. Los tumores glómicos son neoformaciones benignas raras, con presentación más común en zonas distales. Su aparición depende de factores intrínsecos y extrínsecos de los pacientes. Su tasa de recidiva es muy baja en comparación de otros tumores

Introduction. Glomus tumors originate from glomus bodies, which are structures with thermoregulatory function and are distributed throughout the human body, mainly at the distal level of the extremities where it is common to find these characteristic lesions. Although, there are case reports of neoformation presentations with more unusual locations. Their etiology is still unknown. Many times when there is evidence of lesions in atypical areas they are not suspected in many patients and the diagnosis is made incidentally by imaging and/or anatomopathological studies. Clinical case. A 66-year-old female patient with the presence of a glomus tumor in the airway diagnosed by histopathology and immunohistochemistry, underwent surgical resection and presented good evolution after surgery. Discussion. This atypical presentation of glomus tumor in the airway presents mainly with symptoms and signs related to airway obstruction. Timely management is paramount in these patients, and the definitive diagnosis is by histopathology and immunohistochemistry where the presence of the characteristics of glomus cells, vascular structures, smooth muscle and immunostaining positivity towards some markers such as smooth muscle actin, CD34, muscle specific actin, among others, are seen. Conclusion. This type of tumors are rare benign neoformations, with common presentations in distal areas. Their appearance depends on intrinsic and extrinsic factors of the patients and their recurrence rate is very low compared to other tumors

Exploring the performance of Escherichia coli outer membrane vesicles as a tool for vaccine development against Chagas disease

BACKGROUND Vaccine development is a laborious craftwork in which at least two main components must be defined: a highly immunogenic antigen and a suitable delivery method. Hence, the interplay of these elements could elicit the required immune response to cope with the targeted pathogen with a long-lasting protective capacity. OBJECTIVES Here we evaluate the properties of Escherichia coli spherical proteoliposomes - known as outer membrane vesicles (OMVs) - as particles with natural adjuvant capacities and as antigen-carrier structures to assemble an innovative prophylactic vaccine for Chagas disease. METHODS To achieve this, genetic manipulation was carried out on E. coli using an engineered plasmid containing the Tc24 Trypanosoma cruzi antigen. The goal was to induce the release of OMVs displaying the parasite protein on their surface. FINDINGS As a proof of principle, we observed that native OMVs - as well as those carrying the T. cruzi antigen - were able to trigger a slight, but functional humoral response at low immunization doses. Of note, compared to the non-immunized group, native OMVs-vaccinated animals survived the lethal challenge and showed minor parasitemia values, suggesting a possible involvement of innate trained immunity mechanism. MAIN CONCLUSION These results open the range for further research on the design of new carrier strategies focused on innate immunity activation as an additional immunization target and venture to seek for alternative forms in which OMVs could be used for optimizing vaccine development.

Caracterización del cáncer colorrectal en pacientes atendidos en un centro médico del caribe colombiano / Characterization of colorectal cancer in patients treated in a medicalcenter of the Colombian Caribbean

Introducción. A nivel mundial el cáncer colorrectal es la tercera causa de malignidad y la segunda causa de mortalidad por cáncer. En Colombia, tiene una prevalencia de 8,3 % dentro de las patologías neoplásicas, ubicándolo en el tercer lugar, después del cáncer de próstata y de mama, lo que lo cataloga como un problema de salud pública, por lo que es de gran importancia mantener datos actualizados acerca de su perfil epidemiológico. Métodos. Se realizó un estudio transversal en pacientes con cáncer colorrectal atendidos en el Hospital Universitario del Caribe, Cartagena, Colombia, durante el periodo 2015-2019. Se analizaron las variables sociodemográficas, clínicas, patológicas e histológicas. Resultados. Se encontraron un total de 268 pacientes atendidos por cáncer colorrectal, con predominio femenino en el (54,5 %) de los casos, y edad promedio de 62 años; con comorbilidades en 48,8 % y sintomatología de dolor abdominal en 56,7 %. El adenocarcinoma se encontró en el 82,1 % de los casos y la intervención más realizada fue la hemicolectomía derecha. Conclusión. El perfil epidemiológico del cáncer colorrectal encontrado en este estudio concuerda con los hallazgos de la literatura médica mundial, comprometiendo especialmente mujeres en nuestra institución.

Introduction. Worldwide, colorectal cancer is the third leading cause of malignancy and the second leading cause of cancer mortality. In Colombia, it has a prevalence of 8.3% within neoplastic pathologies, placing it in third place, after prostate and breast cancer, which classifies it as a public health problem, making it of great importance to maintain up-to-date data on its epidemiological profile. Methods. A cross-sectional study was carried out in patients with colorectal cancer treated at the Hospital Universitario del Caribe, Cartagena, Colombia, during the period 2015-2019. Sociodemographic, clinical, pathological and histological variables were analyzed. Results. A total of 268 patients treated for colorectal cancer were found, with a female predominance of 54.5% and an average age of 62 years; comorbidities in 48.8%, and symptoms of abdominal pain in 56.7%. Adenocarcinoma was found in 82.1% of cases and the most performed intervention was right hemicolectomy. Conclusion. The epidemiological profile of colorectal cancer found in this study is consistent with the findings of the world medical literature, especially involving women in our institution.

Evaluation of pathogen P21 protein as a potential modulator of the protective immunity induced by Trypanosoma cruzi attenuated parasites

BACKGROUND TcP21 is a ubiquitous secreted protein of Trypanosoma cruzi and its recombinant form (rP21) promotes parasite cell invasion and acts as a phagocytosis inducer by activating actin polymerisation in the host cell. OBJECTIVE Our goal was to evaluate if the additional supplementation of rP21 during a prime/boost/challenge scheme with T. cruzi TCC attenuated parasites could modify the well-known protective behavior conferred by these parasites. METHODS The humoral immune response was evaluated through the assessment of total anti-T. cruzi antibodies as well as IgG subtypes. IFN-γ, TNF-α and IL-10 were measured in supernatants of splenic cells stimulated with total parasite homogenate or rP21. FINDINGS Our results demonstrated that, when comparing TCC+rP21 vs. TCC vaccinated animals, the levels of IFN-γ were significantly higher in the former group, while the levels of IL-10 and TNF-α were significantly lower. Further, the measurement of parasite load after lethal challenge showed an exacerbated infection and parasite load in heart and skeletal muscle after pre-treatment with rP21, suggesting the important role of this protein during parasite natural invasion process. MAIN CONCLUSION Our results demonstrated that rP21 may have adjuvant capacity able to modify the cytokine immune profile elicited by attenuated parasites.