Detection of prostate specific antigen (PSA) in human saliva using an ultra-sensitive nanocomposite of graphene nanoplatelets with diblock-co-polymers and Au electrodes.

Prostate-specific antigen (PSA) is a commonly used biomarker for the detection of prostate cancer (PCa) and there are numerous data available for its invasive detection in the serum and whole blood. In this work, an electrochemical sensing method was devised to detect traces of PSA in human saliva using a hybrid nanocomposite of graphene nanoplatelets with diblock co-polymers and Au electrodes (GRP-PS67-b-PAA27-Au). The pure graphitic composition on filter paper provides significantly high electrical and thermal conductivity while PS67-b-PAA27 makes an amphiphilic bridge between GRP units. The sensor utilizes the binding of an anti-PSA antibody with an antigen-PSA to act as a resistor in a circuit providing an impedance change that in turn allows for the detection and quantification of PSA in saliva samples. A miniaturized electrical impedance analyzer was interfaced with a sensor chip and the data were recorded in real-time using a Bluetooth-enabled module. This fully integrated and optimized sensing device exhibited a wide PSA range of detection from 0.1 pg mL-1 to 100 ng mL-1 (R2 = 0.963) with a lower limit of detection of 40 fg mL-1. The performance of the biosensor chip was validated with an enzyme-linked immunosorbent assay technique with a regression coefficient as high as 0.940. The advantages of the newly developed saliva-PSA electrical biosensor over previously reported serum-PSA electrochemical biosensors include a faster response time (3-5 min) to achieve a stable electrical signal for PSA detection, high selectivity, improved sensitivity, no additional requirement of a redox electrolyte for electron exchange and excellent shelf life. The presented sensor is aimed for clinical commercialization to detect PSA in human saliva.

Meristic and morphometric analysis of two hagfish species (Myxine affinis and Notomyxine tridentiger) from the Magellan Strait, Chile / Análisis nerístico y morfométrico de dos especies de anguila babosa (Myxine affinis y Notomyxine tridentiger) en el Estrecho de Magallanes, Chile

Myxinoids in Chile are represented by the subfamilies Eptatretinae and Myxininae, with a total of 14 species, the identification is complex due to the low level of morphological differentiation that characterizes this taxonomic group. Worldwide, hagfish are species of commercial value, and in Chile many attempts have been reported to initiate small-scale fisheries. The aim of the present study is describe the hagfish species caught in an incipient fishery of the Magellan Strait. Samples were collected in the Magellan Strait during eight fishing expeditions from June 2009 to October 2010 in Bahía Lomas (5348`S; 70°46'W) and Agua Fresca (5323`S; 70°45'W). The samples were taken at two depths, 0-70 meters and 71-140 meters. Taxonomic keys were used to identify the species. All specimens were individuals from the Myxininae subfamily. From a total of 3946 hagfishes, 99 % (n=3905) were the species Myxine affinis and the remaining 1 % were Notomyxine tridentiger, both reported for Chilean and Argentinean Patagonia. The range of variation for meristic variables recorded in this research was wider than those reported in the literature. This could be explained by differences in sample size between the present study and those previously published. Body proportions and meristic variables were not species specific in Myxine sp, so there is a large overlap of ranges between species, which makes their diagnostic use not applicable. This research updates the information and extends the meristic ranges for both species. The esophageocutaneous duct (in N. tridentiger) and the number of fused teeth (bicuspid in M. affinis and tricuspid in N. tridentiger) are the morphological characters that allow a clear identification in the field of the two species.

Los Myxinoideos en Chile están representados por las subfamilias Eptatretinae y Myxininae, con un total de 14 especies, cuya identificación resulta compleja debido al bajo nivel de diferenciación morfológica que caracteriza a este grupo taxonómico. A nivel mundial las anguilas babosas constituyen especies de valor comercial, y en Chile se reportan varios intentos para iniciar pesquerías de pequeña escala. El presente estudio tuvo como propósito la descripción de las especies de anguila babosa capturadas en una pesquería incipiente del Estrecho de Magallanes. Los ejemplares fueron colectados durante ocho expediciones de pesca, desde junio de 2009 a octubre de 2010 en Bahía Lomas (5348`S; 70°46'W) y Agua Fresca (5323`S; 70°45'W). Las muestras fueron tomadas en dos rangos de profundidad, 0-70 metros y 71-140 metros. Todos los especímenes fueron pertenecientes a la subfamilia Myxininae. De un total de 3946 anguilas el 99 % (n=3905) pertenecieron a la especie Myxine affinis y el restante 1 % a la especie Notomyxine tridentiger, ambas reportadas para Chile y la Patagonia Argentina. El rango de variación para las variables merísticas, registradas en esta investigación, fue mayor a los reportados en literatura. Esto puede ser explicado por las diferencias en el tamaño de muestra entre el presente estudio y aquellos publicados previamente. Las proporciones corporales y las variables merísticas no fueron especie-específica en Myxine sp, por lo que existe una gran sobre posición de los rangos entre las especies, lo que hace que su uso como diagnóstico no sea aplicable. Esta investigación actualiza la información y extiende los rangos merísticos para ambas especies. El conducto esofágico-cutáneo (en N. tridentiger) y el número de dientes fusionados (bicúspide en M. affinis y tricúspide en N. tridentiger), son los caracteres morfológicos que permiten una identificación clara de ambas especies.

[Cost of family planning care in 10-19 years old teenagers]. / Costo de atención por servicios de planificación familiar a adolescentes de 10-19 años.

Objetives: To identify the costs of family planning care in adolescents. Material and methods: Longitudinal study of the cost of care for family planning carried out in 2015 in a group of individuals with age limits of 10 and 19 years in a unit first level of health care in the state of Queretaro, Mexico. The profile of use of family planning (FP) was created for the teen was performed services through counseling, provision of contraception and review of intrauterine device (IUD) in a year; cost projections for the population of adolescents and different coverage scenarios between 5 and 100% were made. Results: The average annual cost was 228.84 Mexican pesos. Ideally the identified cost was 2,708.94 pesos. The projection with 20 % coverage was 207,251,330 pesos. The average annual family planning consultations was 0.9. The most commonly used method was with medroxyprogesterone-estradiol at doses of 25 and 5 mg. Conclusion: The cost of planning in adolescents is low, taking into account the costs that the care of high-risk pregnancies and associated comorbidities.

Molecular structure and gas chromatographic retention behavior of the components of Ylang-Ylang oil.

Using quantitative structure-retention relationships (QSRR) methodologies the Kovats gas chromatographic retention indices for both apolar (DB-1) and polar (DB-Wax) columns for 48 compounds from Ylang-Ylang essential oil were empirically predicted from calculated and experimental data on molecular structure. Topological, geometric, and electronic descriptors were obtained for model generation. Relationships between descriptors and the retention data reported were established by linear multiple regression, giving equations that can be used to predict the Kovats indices for compounds present in essential oils, both in DB-1 and DB-Wax columns. Factor analysis was performed to interpret the meaning of the descriptors included in the models. The prediction model for the DB-1 column includes descriptors such as Randic's first-order connectivity index (1X), the molecular surface (MSA), the sum of the atomic charge on all the hydrogens (QH), Randic's third-order connectivity index (3X) and the molecular electronegativity (chi). The prediction model for the DB-Wax column includes the first three descriptors mentioned for the DB-1 column (1X, MSA and QH) and the most negative charge (MNC), the global softness (S), and the difference between Randic's and Kier and Hall's third-order connectivity indexes (3X-3XV).

Revision de vasectomias con tecnica sin bisturi 1989-1994: Clinica para el Hombre de Profamilia / Review of vasectomy with Non scalpel techniques

Se presenta una revisión de la historia de la vasectomía en el mundo y en Colombia. De un universo total de 7.513 vasectomías practicadas en Profamilia se calculó un tamaño de muestra de 2.257 por lo cual se revisaron una de cada 3 historias. Se analizan las fallas de acuerdo a si la ligadura se hizo con seda e interposición de la fascia (1.898 casos con 12 por ciento de fallas), electrocoagulación monopolar e interposición de fascia (227 casos con 1.33 por ciento de fallas), electrocoagulación monopolar sin interposición de fascia (121 casos con 43..8 por ciento), ligadura en seda sin interposición de fascia (9 casos y 0 por ciento de fallas). Se analiza el bajo índice de complicaciones y se postulan algunas teorías relacionadas con las fallas y el tipo de cauterización