ABSTRACT
The nasal administration of therapeutic fluids and vaccines is used to treat allergic rhinitis, sinusitis, congestion, coronaviruses and even Alzheimer's disease. In the latter, the drug must reach the olfactory region, so it finds its way into the central nervous system. Effective administration techniques able to reach the olfactory region are challenging due to the tortuous anatomy of the nasal cavity, and are frequently evaluated in vitro using transparent anatomical models. Here, the liquid distribution inside a 3D printed human nasal cavity is quantified for model fluids resulting from the discharge of a 1-mL syringe with either a spray-generating nozzle, and a straight tip emitting a collimated fluid stream. Experiments using two model fluids with different viscosities suggest that a simple, correctly positioned straight tip attached to a syringe is able to efficiently deliver most of a therapeutic fluid in the human olfactory region in the side-laying position, avoiding the adoption of head-back and head-down positions that can be difficult for patients in the age range typical of Alzheimer's disease. Furthermore, we demonstrate by computer simulations that the conclusion is valid within a wide range of parameters.
Subject(s)
Administration, Intranasal , Computer Simulation , Nasal Cavity , Humans , Administration, Intranasal/methods , Models, Anatomic , Printing, Three-Dimensional , Viscosity , Drug Delivery Systems/methods , Drug Delivery Systems/instrumentationABSTRACT
The floral biology, reproductive system, and visitation behavior of pollinators of four species of columnar cacti, Stenocereus griseus, Pilosocereus moritzianus, Subpilocereus repandus, and Subpilocereus horrispinus, were studied in two arid zones in the north of Venezuela. Our results support the hypothesis that Venezuelan species of columnar cacti have evolved toward specialization on bat pollination. Additional information on the floral biology of a fifth species, Pilosocereus lanuginosus, was also included. All species showed the typical traits that characterize the pollination syndrome of chiropterophily. All species but Pilosocereus moritzianus were obligate outcrossers. Nectar and pollen were restricted to nocturnal floral visitors. Two species of nectar-feeding bats, Leptonycteris curasoae Miller and Glossophaga longirostris Miller, were responsible for practically all the fruit set in these cacti. Frequency of bat visitation per flower per night was highly variable within and between species of cactus, with average frequencies varying between 27 and 78 visits/flower/night. In general terms, the pattern of floral visitation through the night was significantly correlated with the pattern of nectar production and nectar sugar concentration for all species of cactus. Under natural pollination, fruit:flower ratios varied from 0.46 in Subpilocereus repandus to 0.76 in Stenocereus griseus. The efficiency of bat pollination in terms of seed:ovule ratio was high in all species, varying between 0.70 and 0.94.
ABSTRACT
Se realizó el estudio prospectivo, para establecer la prevalencia del HBsAg, en la población residente en áreas urbanas de las tres regiones del Perú. Se incluyeron en cada ciudad 100 personas aparentemente sanas, con tiempo de residencias mayor de 5 años, no migrantes ni trauseuntes. Subdividido cada grupo en 50 adultos y 50 niños. De estos útimos 15, entre 4 meses y 1 año de edad, 15 de 1 a 7 años y 20 casos de 7 a 14 años. Se obtuvieron las muestras por venopuntura, luego se centrifugó y el suero obtenido se almacenó a -20 grados C antes de ser remitido a Lima para su procesamiento. La determinación del HBsAg, se hizo por la técnica de ELISA (Abbott Lab. III. USA). En este reporte preliminar informamos de los resultados en 7 ciudades (Lima, Iquitos, Chiclayo, Arequipa, Ica, Chachapoyas y Tarapoto), que incluyen 680 personas, de los cuales 373 son adultos y 307 niños. El HBsAg, fue positivo en 26 casos (3.8 por ciento). En el grupo adulto hubieron 13 positivos (3.4 por ciento) y en los niños también 13 casos (4.2 por ciento). El resultado de toda la muestra da cifras de prevalencia (3.8 por ciento) superiores a lo reportado, anteriormente a nivel nacional. El mismo fenómeno se observó en zona de costa, mientras que en la zona de selva nuestros resultados son similares a lo encontrado anteriormente. En zonas de sierra no estudiados previamente se obtuvieron resultados similares al resto de país. También es interesante destacar los elevados porcentajes de prevalencia en los niños. Estos resultados indican que la Hepatitis B es un grave problema de salud pública en nuestro país, que amerita tomar medidas preventivas inmediatas
Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Adolescent , Adult , Middle Aged , Hepatitis B virus/immunology , Prospective Studies , Hepatitis B Surface Antigens , PeruABSTRACT
A prospective study was performed in order to establish HBsAg prevalence on population living in urban areas of three geographical regions of Peru. There were included 100 apparently healthy people of each city, with a residence major to 5 years, no migrate neither transitory. Each subdivided group in 50 adults and 50 children. Of these last ones 15 between 1 to 7 years old and 20 cases between 7 to 14 years old. Samples were obtained by venipuncture, then they were centrifuged and the serum obtained was stored at -20 degrees C before being sent to Lima for processing. Determination of HBsAg was made by the Elisa's technic (Abbott Lab-III.-USA). In this preliminary report we informed about results in 7 cities (Lima, Iquitos, Chiclayo, Arequipa,Ica, Chachapoyas y Tarapoto) that include 680 persons of which 373 were adults and 307 children. The HBsAg, was positive in 26 cases (3.8%). In the adult group were 13 positives (3.4%), and in the children also 13 cases (4.2%). Result of all sample shows figures of prevalence (3.8%) major to that reported before at national level. The same phenomenon was observed in the cost while in the jungle our results were similar to those found before. In the andean area not studied previously there were obtained similar results to the rest of the country. It is also interesting to mention the high percentages of prevalence in children. These results indicate that hepatitis B is a serious problem of public health in our country that merit to take immediate prophylactic measures.