Enhancing seedling production of native species to restore gypsum habitats.

Gypsum habitats are widespread globally and are important for biological conservation. Nevertheless, they are often affected by human disturbances and thus require restoration. Sowing and planting have shown positive results, but these actions are usually limited by the lack of native plant material in commercial nurseries, and very little information is available on the propagation of these species. We address this issue from the hypothesis that gypsum added to a standard nursery growing medium (peat) can improve seedling performance of gypsum species and, therefore, optimise the seedling production for outplanting purposes. We test the effect of gypsum on emergence, survival, and growth of nine native plant species, including gypsophiles (exclusive to gypsum) and gypsovags (non-exclusive to gypsum). We used four treatments according to the proportions, in weight, of gypsum:standard peat (G:S), i.e. high-g (50G:50S), medium-g (25G:75S), low-g (10G:90S), and standard-p (0G:100S). Our results showed that the gypsum treatments especially benefited the emergence stage, gypsophiles as group, and Ononis tridentata as a taxon. In particular, the gypsum treatments enhanced emergence of seven species, survival of three species, and growth of two gypsophiles, while the use of the standard peat favoured only the emergence or growth of three gypsovags. Improving emergence and survival at the nursery can provide a reduction of costs associated with seed harvesting, watering, and space, while enlarging seedlings can favour the establishment of individuals after outplanting. Thus, we suggest adding gypsum to standard peat for propagating seedlings in species from gypsum habitats, thereby potentially cutting the costs of restoring such habitats. Our assessment enables us to provide particular advice by species. In general, we recommend using between 25 and 50% of gypsum to propagate gypsophiles, and between 0 and 10% for gypsovags. The results can benefit not only the production of widely distributed species commonly affected by gypsum quarrying, but also of narrow and threatened endemic species that require particularly efficient use of their seeds. In addition, our study highlights the importance of using appropriate growing media to propagate plants characteristic of special substrates for restoration purposes.

Differential effects of alpha-helical and beta-hairpin antimicrobial peptides against Acanthamoeba castellanii.

In this work we evaluated the ability of different types of antimicrobial peptides to promote permeabilization and growth inhibition of Acanthamoeba castellanii trophozoites, which cause eye keratitis. We used cationic alpha-helical peptides P5 and P6, corresponding to the N-terminus of the pore-forming protein from Triatoma infestans, a blood-sucking insect, and a beta-hairpin amphipathic molecule (gomesin), of the spider Acanthoscurria gomesiana haemocytes. A. castellanii permeabilization was obtained after 1 h incubation with micromolar concentrations of both types of peptides. While permeabilization induced by gomesin increased with longer incubations, P5 permeabilization did not increase with time and occurred at doses that are more toxic for SIRC cells. P5, however, at doses below the critical dose used to kill rabbit corneal cells was quite effective in promoting growth inhibition. Similarly, P5 was more effective when serine protease inhibitor was added simultaneously to the permeabilization assay. High performance chromatography followed by mass spectrometry analysis confirmed that, in contrast to gomesin, P5 is hydrolysed by A. castellanii culture supernatants. We conclude that the use of antimicrobial peptides to treat A. castellanii infections requires the search of more specific peptides that are resistant to proteolysis.

Random amplified polymorphic DNA profiles as a tool for the characterization of Brazilian keratitis isolates of the genus Acanthamoeba.

The genus Acanthamoeba comprises free-living amebae identified as opportunistic pathogens of humans and other animal species. Morphological, biochemical and molecular approaches have shown wide genetic diversity within the genus. In an attempt to determine the genetic relatedness among isolates of Acanthamoeba we analyzed randomly amplified polymorphic DNA (RAPD) profiles of 11 Brazilian isolates from cases of human keratitis and 8 American type culture collection (ATCC) reference strains. We found that ATCC strains belonging to the same species present polymorphic RAPD profiles whereas strains of different species show very similar profiles. Although most Brazilian isolates could not be assigned with certainty to any of the reference species, they could be clustered according to pattern similarities. The results show that RAPD analysis is a useful tool for the rapid characterization of new isolates and the assessment of genetic relatedness of Acanthamoeba spp. A comparison between RAPD analyses and morphological characteristics of cyst stages is also discussed.

[Ischemic cardiomyopathy in a child. Case report with accentuated coronary disease]. / Miocardiopatia isquêmica na criança. Relato de caso com acentuada coronariopatia.

Ischemic cardiomyopathy in childhood is related with congenital and acquired pathologies which could lead to serious cardiac sequelae as myocardial infarction and sudden death. Unfortunately, when coronary artery malformations are excluded, it is difficult in some cases to be completely certain on the etiology of the arterial coronary disease, due the lack of pathognomonic diagnostic tests. Case report of 6 year old child, with severe coronary artery disease: aneurysm of main branch of left coronary artery; left anterior descending branch and right coronary artery occlusions with accentuated myocardial dysfunction. We believe that the diagnosis of Kawasaki disease is presumptive in this patient. The principal aspects to elucidate the etiology of coronary artery disease are analysed, as well as the importance of identifying patients without known previous illness, but with severe coronary artery lesions, as in this reported case.

[Agenesis of the right pulmonary artery with severe pulmonary hypertension, attenuated by surgical correction]. / Agenesia da artéria pulmonar direita com acentuada hipertensão pulmonar, atenuada por correção cirúrgica.

A 22 months old infant with agenesis of right pulmonary artery, without other associated congenital heart defects, is reported. Reconstruction of pulmonary arteries by connecting them through a 7mm Goretex tube was performed, with clear clinical improvement in view of disappearance of signs of cardiac insufficiency and of hypoxemia. Contralateral pulmonary hypertension, at systemic level, decreased to 77% in the immediate postoperative period. So, this technique becomes the first option, before considering these cases for cardiopulmonary transplantation.

[Transluminal angioplasty in total anomalous drainage of obstructed pulmonary veins. A case report]. / Angioplastia transluminal na drenagem anômala total de veias pulmonares na forma obstrutiva. Relato de caso.

Transluminal balloon angioplasty has been successfully used in the treatment of various congenital heart diseases, specially in pulmonary valve stenosis. Dilation angioplasty has also been used in venous obstructions in children, but the results have been contradictory. This report describes the case of a three-month-old female infant with obstructed total anomalous pulmonary venous return into the right superior vena cava. Percutaneous angioplasty was performed with two 4 mm diameter balloon catheters (Simpson Ultra Low Profile), with success. Right ventricular systolic pressure decreased from 68 to 49 mmHg and mean pulmonary vein pressure decreased from 41 to 17 mmHg. There was significant clinical improvement. Although it would be an unique experience in our Department, authors suggest that transluminal balloon angioplasty could be an initial therapeutic alternative in infants with obstructive total anomalous pulmonary venous return, a high-risk group for total surgical repair.

Serine-like proteolytic enzymes correlated with differential pathogenicity in patients with acute Acanthamoeba keratitis.

Acute ocular infection due to free-living amoebae of the genus Acanthamoeba is characterized by severe pain, loss of corneal transparency and, eventually, blindness. Proteolytic enzymes secreted by trophozoites of virulent Acanthamoeba strains have an essential role in the mechanisms of pathogenesis, including adhesion, invasion and destruction of the corneal stroma. In this study, we analysed the relationship between the extracellular proteases secreted by clinical isolates of Acanthamoeba and the clinical manifestations and severity of disease that they caused. Clinical isolates were obtained from patients who showed typical symptoms of Acanthamoeba keratitis. Trophozoites were cultivated axenically, and extracellular proteins were collected from cell culture supernatants. Secreted enzymes were partially characterized by gelatin and collagen zymography. Acanthamoeba trophozoites secreted proteases with different molecular masses, proteolysis rates and substrate specificities, mostly serine-like proteases. Different enzymatic patterns of collagenases were observed, varying between single and multiple collagenolytic activities. Low molecular weight serine proteases were secreted by trophozoites associated with worse clinical manifestations. Consequently, proteolytic enzymes of some Acanthamoeba trophozoites could be related to the degree of their virulence and clinical manifestations of disease in the human cornea.

Twenty years of acanthamoeba keratitis.

PURPOSE: We described the rate of Acanthamoeba keratitis (AK) in a referral eye center in São Paulo, Brazil, through a retrospective review of clinical and laboratorial records of patients over 2 decades. METHODS: From 1987 to 2006, a total of 581 requests for amoebic laboratory workup in cases of infectious keratitis were investigated. Statistical analyses were applied to analyze a tendency of AK cases. RESULTS: Acanthamoeba species were cultured from corneal scrapings of 185 patients, 5 of them with bilateral infection. Eighty-three percent of those patients were related with contact lens wear. CONCLUSIONS: The results suggested that patients with AK have persisted and increased over time at our ophthalmology center. Contact lenses showed to be a potential risk factor. Amoebic corneal infection can be considered as a new but well-established disease in Brazilian ophthalmology and visual sciences.

Levels of lipoprotein (a) in pulmonary arterial hypertension.

We compared the levels of lipoprotein (a) in 48 Caucasian patients with pulmonary arterial hypertension, comprising 32 females and 16 males, aged 28.0 +/- 12.0 years, with a range from 4 through 52 years, with 48 normal Caucasian subjects matched for age and sex. Pulmonary hypertension was secondary in 41 patients with Eisenmenger's syndrome, these comprising 27 females and 14 males aged 27.0 +/- 12.0 years, with a range from 4 through 51 years, and primary in the other 7 patients, 5 females and 2 males, whose age was 30.0 +/- 14.0 years, with a range from 9 through 52 years. Lipoprotein (a) was measured using an immunoprecipitation and turbidimetric assay after a 12 hour fast. Levels of the protein, expressed as the median (% 25; % 75), were higher in those with Eisenmenger's syndrome than in normal controls (p=0.003). In addition, there was a greater prevalence of levels of lipoprotein greater than 30.0 mg/dl in those with secondary pulmonary arterial hypertension patients than in our normal population (p = 0.03). We have found no differences, however, in the levels of lipoprotein(a) in those who had primary pulmonary arterial hypertension when compared with their matched controls, albeit that the number of patients studied was small. We conclude that increased levels of lipoprotein (a) may be secondary to pulmonary arterial hypertension as a marker of tissue damage or may be genetically determined. In either way, the increase in lipoprotein (a) could be an additional factor predisposing to the vascular alterations known to occur in this disease.

Random amplified polymorphic DNA profiles as a tool for the characterization of Brazilian keratitis isolates of the genus Acanthamoeba

The genus Acanthamoeba comprises free-living amebae identified as opportunistic pathogens of humans and other animal species. Morphological, biochemical and molecular approaches have shown wide genetic diversity within the genus. In an attempt to determine the genetic relatedness among isolates of Acanthamoeba we analyzed randomly amplified polymorphic DNA (RAPD) profiles of 11 Brazilian isolates from cases of human keratitis and 8 American type culture collection (ATCC) reference strains. We found that ATCC strains belonging to the same species present polymorphic RAPD profiles whereas strains of different species show very similar profiles. Although most Brazilian isolates could not be assigned with certainty to any of the reference species, they could be clustered according to pattern similarities. The results show that RAPD analysis is a useful tool for the rapid characterization of new isolates and the assessment of genetic relatedness of Acanthamoeba spp. A comparison between RAPD analyses and morphological characteristics of cyst stages is also discussed (au)