Birth prevalence and characteristics of congenital toxoplasmosis in Sergipe,North‐east Brazil

Objectives To estimate, by neonatal screening, the birth prevalence of congenital toxoplasmosis among live‐born infants in Sergipe state, Brazil, and to investigate the clinical features of affected infants. Methods Dried blood spot specimens obtained from 15 204 neonates were assayed for the presence of anti‐T. gondii IgM antibodies. Duplicate retesting was done in infants with positive and borderline results. Confirmatory testing in peripheral blood samples consisted of testing for anti‐T. gondii IgG and IgM in infants and mothers. Those with possible congenital toxoplasmosis were evaluated and followed up to a median age of 20 months. Congenital infection was confirmed in the presence of persisting anti‐T. gondii IgG antibodies beyond 12 months of age. All infants with confirmed infection were treated with pyrimethamine, sulfadiazine and folinic acid for 1 year. Results Fifty‐three infants had detectable IgM in dried blood spot specimens. Confirmatory testing was reactive in 39/50, of which, 38 completed follow‐up. Six of 15 204 newborns were diagnosed with congenital toxoplasmosis, resulting in an estimated birth prevalence of four per 10 000 [CI 95% 1.4–8.0]. Four infants (67%) showed signs of congenital toxoplasmosis in their first year of life; three (75%) had retinochoroidal scars, and one had cerebral calcifications. Two infants remained asymptomatic until 20 months of age. Conclusions The birth prevalence of congenital toxoplasmosis is high in the Brazilian state of Sergipe, with most of the infants showing ocular lesions. Preventive measures are strongly warranted.     

Case for diagnosis

Pigmentary demarcation lines are physiologically abrupt transition lines from areas of deeper pigmentation to less pigmented areas. They are most often seen in African and Japanese individuals and rarely observed in Caucasians. There are eight types of pigmentary demarcation lines. The one described here, type B, is restricted to women and is associated with pregnancy in non-black patients. This type of pigmentary demarcation line occurs in the posterior aspect of the legs, extending from the perineum to the ankle. Its distribution follows the Voigt''s lines, which define the distribution of peripheral nerves. Its pathogenesis remains unknown. Expectant treatment is used, and good results have been reported with the use of Q-switched Alexandrite laser.     

Automatic Methods for Carotid Contrast-Enhanced Ultrasound Imaging Quantification of Adventitial Vasa Vasorum

Adventitial vasa vasorum are physiologic microvessels that nourish artery walls. In the presence of cardiovascular risk factors, these microvessels proliferate abnormally. Studies have reported that they are the first stage of atheromatous disease. Contrast-enhanced ultrasound (CEUS) of the carotid allows direct, quantitative and non-invasive visualization of the adventitial vasa vasorum. Hence, the development of computer-assisted methods that speed image analysis and eliminate user subjectivity is important. We developed methods for automatic analyses and quantification of vasa vasorum neovascularization in CEUS and tested these methods in a cohort of 186 individuals, 63 of whom were healthy volunteers. We implemented alternative automatic strategies for using the images to stratify patients according to their risk group and compare the strategies with respect to diagnostic performance. An automatic single-parameter strategy performs less effectively than the corresponding Arcidiacono method based on manual interpretation of the images (68 < area under the receiver operating characteristic curve [AUROC] for the manual Arcidiacono method < 82; 60 < AUROC for the automatic single-parameter strategy < 63). However, by use of additional image parameters, an automatic multiparameter strategy has significantly improved performance with respect to the manual Arcidiacono method (78 < AUROC < 90). The automatic multiparameter strategy is a valuable alternative to the manual Arcidiacono method, improving both diagnostic speed and diagnostic accuracy.     

Influence of Oxynitrided Surface in the Production of a Less Susceptible Titanium Surface to Skin‐Borne Bacterial Adhesion

There is a growing quest for an ideal biomaterial that shows appropriate cellular response and is not susceptible to microbial adhesion. In this study, commercial grade II titanium was submitted to RF/DC plasma surface modification at 2.2 mbar, using gas mixtures of argon, nitrogen, and oxygen at proportions 4:1:2 and 4:1:3. The surfaces were physically and chemically characterized. In order to evaluate bacterial response, the surfaces were exposed to Staphylococcus epidermidis. Oxynitrided samples, although having a higher roughness as compared with untreated samples, exhibited lower bacterial growth. This observation is probably due to the formation of different crystalline phases of nitrides and oxides caused by plasma treatment. The surface with highest contact angle and highest surface tension showed lower bacterial adhesion. These results were confirmed by scanning electron microscopy. The role of nitrogen in reducing bacterial adhesion is clear when this material is compared with untreated titanium, on which only an oxide film is present.     

Incidence of Trypanosoma cruzi transmission through breastfeeding during acute experimental Chagas disease

ObjectiveTo verify the incidence of T. cruzi transmission through breastfeeding during acute experimental Chagas’ disease.MethodsFifteen female Swiss mice were mated and, after pregnancy confirmation, placed in individual cages. A few hours after birth, the females were inoculated with 0.1 mL of blood containing approximately 3 × 10⁵ trypomastigote forms of Y strain of T. cruzi and continued breastfeeding for 25 days.ResultsIn 142 offspring examined no infection through breastfeeding was observed.ConclusionsThe low number of trypomastigote forms ingested by the newborn mice combined with biological and biochemical characteristics of blood trypomastigotes may explain the lack of transmission in this experiment.     

A new nanoemulsion formulation improves antileishmanial activity and reduces toxicity of amphotericin B

This work aimed to optimise a new nanoemulsion (NE) formulation loaded with Amphotericin B (AmB) and to evaluate its in vivo antileishmanial activity and in vitro haemolytic toxicity. The influence of gradual increases in pressure, using a high-pressure homogeniser, was evaluated. The NE was characterised for droplet size, polydispersity index, zeta potential and encapsulation efficiency (EE). For antileishmanial activity studies, AmB-NE was administered intravenously in mice infected by Leishmania infantum chagasi, which causes Visceral Leishmaniasis (VL). When the NE was submitted to gradual increases in pressure, the PI values and droplet size decreased. The droplet size (～145?nm) was lower than that obtained in previous studies. The zeta potential was negative and the EE was almost 100%. The haemolytic toxicity, evaluated on human red blood cells, for AmB-loaded NE was lower than that observed for the conventional AmB (C-AmB). C-AmB at 2?mg/kg was very toxic. In contrast, administration of the AmB-loaded NE, at same dose, did not result in any sign of acute toxicity, promoting a significant reduction in parasite burden as compared to the C-AmB. These findings suggest that this new AmB-loaded NE constitutes an attractive alternative for the treatment of VL due to improved efficacy and lower toxicity.