When Less Is More: Sex Ratios for the Mass-Rearing of Anastrepha ludens (Diptera: Tephritidae).

Anastrepha ludens (Loew) is one of the most important pests of citrus and mango crops in Mexico. A method used to control this pest is the sterile insect technique, which consists in the mass production, irradiation, and release of insects in affected areas. The production of insects begins with the establishment of colonies to produce eggs, which must be highly fertile to ensure an adequate production of larvae. However, female fecundity and fertility can be affected by adult density and sex ratio, thus an optimal sex ratio in mass-rearing cages must be used. The genetic sexing strain of A. ludens (Tapachula-7) allows the identification of the sex at the pupal stage, making it possible to establish rearing cages with different sex ratios. We determined if different sex ratios have an effect on egg production. Two sex ratios (4♀: 1♂ and 1♀: 1♂) were compared. Fecundity, fertility and survival at different ages were also determined. Higher fertility and fecundity per female were observed at a ratio of 4:1. However, females with higher fecundity had reduced survival probabilities. In conclusion, maintaining colonies with a lower proportion of males in cages ensures a greater fecundity and fertility. Further research is necessary to understand whether results can be attributed to lower male harassment in cages.

Formation of nanotubular TiO2 structures with varied surface characteristics for biomaterial applications.

Nanotubular structures were generated on the surface of titanium c.p. by anodization technique in an aqueous solution of acetic acid (14% v/v) with different sources of fluoride ion (HF, NaF, NH4 F). The aim of using these three different compounds is to study the effect of the counterion (H+ , Na+ and NH4+) on the morphology, wettability and surface free energy of the modified surface. Nanotubes were generated at 10 and 15 V for each anodizing solution. To further improve surface characteristics, the samples were heat-treated at 600°C for 4 h and at 560°C for 3 h. SEM images revealed the formation of nanotubes in all anodizing conditions, while their diameter increased proportionally to the electric potential. X-ray diffraction and micro-Raman spectroscopy results showed the presence of both anatase and rutile phases, with a higher content of rutile in the coatings obtained using NH4 F and an applied potential of 10 V. The heat-treatment significantly increased the wettability of the anodic coatings, especially for the coating obtained at 15 V with HF, which showed values < 7 degrees of contact angle. Besides, the nanotubes show a decrease in diameter due to the heat treatment, except for the nanotubes formed in NH4 F. Depending on their surface properties (e.g. low contact angle and high surface free energy), these coatings potentially have great potential in biomedical applications, sensors devices, and catalytic applications among others. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1341-1354, 2018.

Frecuencia de insuficiencia de Vitamina D en adultos jóvenes sanos de Asunción / Frequency of Vitamin D insufficiency in healthy young adults of Asunción

La insuficiencia de vitamina D sérica se asocia a diversos trastornos, con alta prevalencia a nivel regional y mundial. En nuestro país no existen estudios publicados al respecto. En este estudio observacional, descriptivo, con componente analítico se determinaron niveles de vitamina D y prevalencia de su insuficiencia en jóvenes y se indagó posibles asociaciones con factores de riesgo conocidos como la falta de exposición solar, uso de protectores solares, y falta de consumo de alimentos ricos en vitamina D. Fueron incluidos 100 estudiantes y funcionarios del Hospital de Clínicas de la Universidad Nacional de Asunción, a quienes se les tomó una muestra de sangre y llenaron un cuestionario. Los niveles de vitamina D fueron determinados por el método ECLIA (inmunoensayo de electro quimioluminiscencia). Las edades estaban entre 20 y 30 años, el 69% era del sexo femenino. La concentración media ± desvío estándar de vitamina D fue de 17,6 ± 6,25 ng/dl (rango: 4-38). El 53% de los participantes presentaba insuficiencia (10 a 20 ng/dL) y 11% deficiencia (<10 ng/dL) de vitamina D. Aunque los participantes que reportaron consumir lácteos y no utilizar protectores solares tuvieron mayores niveles de vitamina D, la diferencia no fue estadísticamente significativa. Se encontró una frecuencia elevada de insuficiencia de vitamina D en esta población, en concordancia con los hallazgos de estudios similares a nivel mundial y regional. Se recomienda la suplementación con vitamina D en la población de manera a prevenir los trastornos asociados con la deficiencia de esta vitamina.

Insufficientserum vitamin D is associated with various disorderswith highprevalence at global and regional levels. In our country,there are notpublishedstudiesrelated to this matter.Inthisdescriptive,observational studywithanalytical component,thelevels ofvitamin Dand the prevalence of its insufficiencywere determined in young peopleand also thepossible associations with knownriskfactors likesun exposure, sunscreen useand lack ofconsumption ofvitamin D-enrichedfoodswere analyzed.One hundred medical students andmembers of thestaff of theHospital de Clinicas ofthe National University of Asuncion, Paraguaywere included.Participants wereaged 20to30 yearsand69%of them werewomen.The mean concentrationof vitamin Dwas 17.6 ± 6.25 ng/dl (range: 4-38);53% oftheparticipants had insufficientlevelsof vitamin D(10-20 ng/dL) and 11%had vitamin Ddeficiency (less than 10 ng/dL).Althoughtheindividuals whoreportedconsumption of dairyproductsand non-use of sunscreenhad higher levels ofvitamin D,thedifferencewas not statistically significant. A high frequency ofvitamin D insufficiency was foundin this population in agreementwith similarstudiescarried outatworldwideandregionallevels.Vitamin D supplementationisrecommendedin thepopulation to prevent disorders associated withthedeficiency.

Activation of sucrose-phosphate synthase by a protein factor/sucrose-phosphate phosphatase.

The possible presence of a sucrose-phosphate synthase (SPS) activating/stabilizing factor (SAF) presumably lost during SPS purification was investigated. Rice leaf protein extracts were chromatographed in a DEAE-Sephacel column. SPS activity of previously purified rice enzyme was enhanced to different extent by aliquots of fractions from such column. The activating capacity could not be replaced by albumin, but was nullified by EDTA. When the fractions were boiled or treated with TCA, the activating capacity disappeared suggesting its proteinaceous nature. The presence of 10 microM okadaic acid had no effect on the stimulatory action of SAF on SPS denying the possibility to SAF to be a SPS-phosphatase. Although it overlaps somehow with sucrose synthase (SS) in DEAE-Sephacel fractions, the activating protein factor and SS eluted separately during Sephadex G-200 chromatography. The activating ability was saturable at a fixed SPS concentration and was able to enhance SPS activity from other plant sources. Simultaneous studies on the activities of SPS and sucrose-phosphate phosphatase (SPP), closely linked to SPS, allowed us to suggest that SAF could be SPP. The presence of SAF/SPP did not alter the affinity of SPS for its substrates but helped to reverse the Pi inhibition at low Fru-6-P concentrations. We conclude that SPS may possibly interact with SPP, contributing to a more effective sucrose synthesis.

[Randomized comparative study of induced labor with oxytocin and misoprostol in prolonged pregnancies]. / Estudio comparativo randomizado de inducción de parto con ocitocina y misoprostol en embarazos en vías de prolongación.

UNLABELLED: The efficacy of oxytocin for induction of labor at 41 to 42 weeks of gestational age, was compared with misoprostol (a PGE1 analog) in 100 pregnant women. Half a tablet containing 100 mcg of misoprostol was placed intravaginally in 50 women and the remaining 50 received iv oxytocin (2-32 mU/min). The obstetric features were similar in both groups. Delivery within 24 hours was achieved in 88% of the patients induced with misoprostol and in 72% with oxytocin (p < 0.05). The mean time from induction to delivery was similar, 10.3-10.9 hrs (p NS) and no differences in obstetric and perinatal outcomes were found. Polisystoly with misoprostol, was the only side effect observed in the study (11.4%), and was without neonatal consequences. CONCLUSION: intravaginal misoprostol (100 mcg), is more effective, cheaper and less stressful than IVI oxytocin in post term inductions. The safety profiles of both were similar.

Increased affinity of histamine H1 binding to membranes of human myometrium at the end of pregnancy.

1. The characterization of H1 binding sites in membrane preparations of human myometrium obtained from pregnant and non-pregnant women was performed by using 3H-mepyramine as the radioactive ligand. 2. Saturation curve analysis revealed that 3H-mepyramine is bound to a single class of binding sites. Changes in the H1 site binding parameters were observed at the end of pregnancy, resulting in an increased affinity relative to non-pregnant tissue (Kd: 131.0 +/- 8.8 (non-pregnant) and 72.5 +/- 7.5 (pregnant) nM, n = 6, P < 0.01). 3. A reduction in receptor concentration at the end of pregnancy was also observed, [Bmax: 565.2 +/- 43.7 (non-pregnant) and 309.6 +/- 25.9 (pregnant) fmol/mg prot, n = 6, P < 0.01]. It is possible that this reduction in Bmax could be attributed to a dilution factor due to the increase in membraneous proteins that occurs during gestation.

[Normative parameter characterization for the auditory brainstem response of the normal newborn]. / Caracterizacion de los parametros normativos del potencial evocado auditivo del recien nacido normal.

The auditory brainstem response generated by clicks was studied in 119 normal newborns. One ear was studied in detail at 20, 40 and 60 dBnHL, the other at 20 and 30 dBnHL, increasing the intensity if no response was found. The latency for waves I, III and V in the detailed studied ear was 2.7 +/- .39, 5.4 +/- .44 and 7.7 +/- .48, respectively. 85% of newborns had thresholds for auditory brainstem response less than 40 dBnHL, 54% less than 20 dBnHL and 15% between 40 and 60 dBnHL. These findings are compatible with conductive loss in the higher threshold group and support data from Stockard, regarding high risk groups. Additionally, our data suggests that an adequate level to screen for hearing loss in newborns is between 30 and 40 dBnHL.

Microiontophoresis of kanamycin from micropipettes in vitro.

1. Currents ranging between 10 and 50 nA were passed during ten minutes through 0,02 M kanamycin (KM) filled micropipettes with tips submerged in 25 microliters of KCl 0,15 M. 2. The amount of KM released was measured by radioimmunoassay. 3. It was found that the amount of kanamycin released could be computed by the equation y = 0,16x + 0,59; where "x" stands for charge passed in micro Coulombs and "y" stands for the amount released in nanograms. 4. When Faraday's law was used to fit the experimental data, it was found that the electrodes behave in an acceptable linear fashion. The range of the transport number for KM was 0,089 to 0,142 for six electrodes.