Solid lipid nanoparticles containing copaiba oil and allantoin: development and role of nanoencapsulation on the antifungal activity.

The aim of this work was to develop solid lipid nanoparticles (SLN) containing copaiba oil with and without allantoin (NCOA, NCO, respectively) and to evaluate their antifungal activity. Nanoparticle suspensions were prepared using a high homogenisation technique and characterised by dynamic light scattering, laser diffraction, nanoparticle tracking analysis, multiple light scattering analysis, high-pressure liquid chromatography, pH and rheology. The antifungal activities of the formulations were tested in vitro against the emergent yeasts Candida krusei and Candida parapsilosis, and the fungal pathogens of human skin Trichophyton rubrum and Microsporum canis. The dynamic light scattering analysis showed z-average diameters (intensity) between 118.63 ± 8.89 nm for the nanoparticles with both copaiba oil and allantoin and 126.06 ± 9.84nm for the nanoparticles with just copaiba oil. The D[4,3] determined by laser diffraction showed similar results of 123 ± 1.73 nm for the nanoparticles with copaiba oil and allantoin and 130 ± 3.6 nm for the nanoparticles with copaiba oil alone. Nanoparticle tracking analysis demonstrated that both suspensions had monomodal profiles and consequently, the nanoparticle populations were homogeneous. This analysis also corroborated the results of dynamic light scattering and laser diffraction, exhibiting a smaller mean diameter for the nanoparticles with copaiba oil and allantoin (143 nm) than for the nanoparticles with copaiba oil (204 nm). The physicochemical properties indicated that the dispersions were stable overtime. Rheology evidenced Newtonian behaviour for both suspensions. Antifungal susceptibility showed a MIC90 of 125 µg/mL (nanoparticles with copaiba oil) and 7.8 µg/mL (nanoparticles with copaiba oil and allantoin) against C. parapsilosis. The nanoparticles with copaiba oil and the nanoparticles with copaiba oil and allantoin presented a MIC90 of 500 µg/mL and 250 µg/mL, respectively, against C. krusei. The MIC90 values were 500 µg/mL (nanoparticles with copaiba oil) and 1.95 µg/mL (nanoparticles with copaiba oil and allantoin) against T. rubrum. Against M. canis, the nanoparticles with copaiba oil and allantoin had a MIC9 of 1.95 µg/mL. In conclusion, nanoencapsulation improved the antifungal activity of copaiba oil, which was enhanced by the presence of allantoin. The MICs obtained are comparable to those of commercial products and can represent promising therapeutics for cutaneous infections caused by yeasts and dermatophytes.

[Prevalence of retinopathy of prematurity in very low birth weight infants]. / Prevalência da retinopatia da prematuridade em recém-nascidos de muito baixo peso.

OBJECTIVE: Evaluate the prevalence of retinopathy of prematurity (ROP) in very low birthweight infants (birthweight<1500 g). METHOD: A prospective examination was conducted on 102 neonates with very low birthweight admitted to the BAM-HC (FMUSP) between 01/01/92 and 12/31/93. The mapping of the retina with scleral depression was first conducted between 3rd and the 8th weeks of life, and it was repeated every 1 to 4 weeks until the vascularization of the retina was complete or the ROP was present. To classify the ROP the International Classification of ROP was used. For the purposes of statistical analysis, the most serious phase of ROP presented by the neonate was considered. RESULTS: In this study retinopathy of prematurity was present in 29.09% of the neonates, in 78.5% of those under 1,000 g of birthweight, and 72.73% of those with less than 30 weeks of gestational age. Among the newborns with ROP, 77.05% were in phase 1, 13.11% in phase 2, and 9.84% in phase 3. Oxygen in mechanical ventilation and "CPAP" were statistically significant factors for the development the ROP. CONCLUSION: The ophthalmologic examination between the 3rd and 4th weeks of life was an important instrument for the detection of RP and should be done in all very low birth weight infants (weight<1,500 g), especially in neonates with less than 1,250 g and/or gestational age under 34 weeks.

Diffuse unilateral subacute neuroretinitis in South America.

We describe two cases of diffuse unilateral subacute neuroretinitis in South America. These Brazilian patients presented with subretinal worms similar in size to those described in the southeastern United States. This is the first report, to our knowledge, of diffuse unilateral subacute neuroretinitis occurring outside the United States and Caribbean Islands.

Funduscopic alterations in SS and SC hemoglobinopathies. Study of a Brazilian population.

Fundus changes in sickle cell disease are well studied and documented according to their clinical and angiographic aspects. Sickle cell retinopathy was studied in a Brazilian population of 63 patients (41 with SS hemoglobinopathy, and 22 with SC hemoglobinopathy). All ophthalmoscopic changes observed in our patients were more frequent in the SC group with the exception of atrophic retinal tears, found only in the SS group. Proliferative retinopathy including its complications was seen in 54.54% of the eyes of the SC group, and in only 14.64% of the eyes of the SS group. Decreased vision is consequently greater in the SC group. Despite the great frequency of funduscopic changes in both groups, only 1 patient suffered irreversible visual loss due to retinal detachment operated on without success.

Osseous choristoma of the choroid. A familial disease.

Two patients in the same family (daughter and mother) had osseous choristoma of the choroid in four otherwise normal eyes. The clinical diagnosis of the choroidal lesion was confirmed by B-scan ultrasonography. Both patients were followed up for five years and neither showed any essential change of the fundus. The high prevalence of this choroidal tumor in girls and women (20 of 22 reported cases) and the present report on two patients in the same family suggest that a hereditary factor should be considered in the etiology of this unusual choroidal lesion.