Revisiting autopsies of death by mechanical asphyxia in the search for post-mortem pink teeth.

BACKGROUND: In contemporary forensic practice, Medicine and Dentistry combine forces to improve the search for the cause of death and human identification. The pink tooth phenomenon (PTP) is a cadaveric sign that allegedly manifests more often in victims of asphyxia. However, the scientific literature is scarce and controversial on this aspect. OBJECTIVE: This study aimed at screening victims of mechanical asphyxia in order to search for post-mortem pink teeth. MATERIAL AND METHODS: Retrospectively, autopsy reports from a local medico-legal institute in South Brazil were revisited in the search for victims of death by asphyxia. Autopsy reports of twenty one victims aged between 6 and 67 years (mean age: 40.6 years ±19.20; median: 37 years) were found and analyzed. RESULTS: The different modalities of asphyxia included drowning (n=7; 33.33%), strangulation (n=1; 4.76%) and hanging (n=13; 61.91%). A single case of PTP was detected (4.76%) - a 26-year-old male victim of hanging. CONCLUSION: This study illustrates and highlights the unspecific aspect of the PTP. In practice, forensic experts must avoid interpretations of this phenomenon as conclusive evidence of the cause of death, such as asphyxia by drowning, strangulation or hanging.

A simple enzymatic method for examining calcite ossicles of Echinodermata.

The various shapes, size and fine details of ossicles are of paramount importance as systematic characters in the Echinodermata. The ossicles in this group are endodermal and a method to free them from the dermis is essential for their study. To date, a small quantity of hypochlorite solution (usually household liquid bleach) has been used to dissolve a small piece of tissue and, consequently, free these ossicles. A new method, using a proteolytic enzyme instead of hypochlorite solution to dissolve holothurian tissues, is proposed. This method was tested on fragments of body tissues from three species in three different orders of holothurians: Holothuria grisea Selenka, 1867 (Aspidochirotida), Duasmodactyla seguroensis (Deichmann, 1930) (Dendrochirotida) and Synaptula secreta Ancona Lopez (1957) (Apodida). Observations of material prepared using the hypochlorite and the enzyme methods were made using scanning electron microscopy (SEM). The SEM images show the striking differences in the surface of the ossicles obtained by each method, and reveal the advantages of the enzyme method.

Newborn screening for biotinidase deficiency in Brazil: biochemical and molecular characterizations.

Biotinidase deficiency is an inherited metabolic disorder characterized by neurological and cutaneous symptoms. Fortunately, it can be treated and the symptoms prevented by oral administration of the vitamin biotin. Using dried blood-soaked filter paper cards, biotinidase activity was determined in the sera of 225,136 newborns in Brazil. Mutation analysis performed on DNA from 21 babies with low serum biotinidase activity confirmed that 3 had profound biotinidase deficiency (less than 10% of mean normal sera biotinidase activity), 10 had partial biotinidase deficiency (10 to 30% of mean normal serum activity), 1 was homozygous for partial biotinidase deficiency, 4 were heterozygous for either profound or partial deficiency, and 3 were normal. Variability in serum enzyme activities and discrepancies with mutation analyses were probably due to inappropriate handling and storage of samples sent to the laboratory. Obtaining an appropriate control serum at the same time as that of the suspected child will undoubtedly decrease the false-positive rate (0.09%). Mutation analysis can be used to confirm the genotype of these children. The estimated incidence of biotinidase deficiency in Brazil is about 1 in 9,000, higher than in most other countries. Screening and treatment of biotinidase deficiency are effective and warranted. These results strongly suggest that biotinidase deficiency should be included in the newborn mass screening program of Brazil.

Newborn screening for biotinidase deficiency in Brazil: biochemical and molecular characterizations

Biotinidase deficiency is an inherited metabolic disorder characterized by neurological and cutaneous symptoms. Fortunately, it can be treated and the symptoms prevented by oral administration of the vitamin biotin. Using dried blood-soaked filter paper cards, biotinidase activity was determined in the sera of 225,136 newborns in Brazil. Mutation analysis performed on DNA from 21 babies with low serum biotinidase activity confirmed that 3 had profound biotinidase deficiency (less than 10 percent of mean normal sera biotinidase activity), 10 had partial biotinidase deficiency (10 to 30 percent of mean normal serum activity), 1 was homozygous for partial biotinidase deficiency, 4 were heterozygous for either profound or partial deficiency, and 3 were normal. Variability in serum enzyme activities and discrepancies with mutation analyses were probably due to inappropriate handling and storage of samples sent to the laboratory. Obtaining an appropriate control serum at the same time as that of the suspected child will undoubtedly decrease the false-positive rate (0.09 percent). Mutation analysis can be used to confirm the genotype of these children. The estimated incidence of biotinidase deficiency in Brazil is about 1 in 9,000, higher than in most other countries. Screening and treatment of biotinidase deficiency are effective and warranted. These results strongly suggest that biotinidase deficiency should be included in the newborn mass screening program of Brazil.

High prevalence of congenital toxoplasmosis in Brazil estimated in a 3-year prospective neonatal screening study.

BACKGROUND: A pilot neonatal screening programme revealed a high (approximately 1 per 4800 live births) prevalence of congenital toxoplasmosis (CT) in the State of Rio Grande do Sul, Brazil. The purpose of this paper was to estimate in a larger prospective study the prevalence of CT in the country. METHODS: At the beginning of the study, an in-house indirect enzyme immunoassay (EIA) was used, to be later replaced with a commercial capture IgM fluorometric enzyme immunoassay (FEIA). Both methods detect specific anti-Toxoplasma gondii IgM-class antibodies eluted from dried blood spots. RESULTS: Of the total of 140,914 samples received from all over the country, 47 cases were identified and confirmed as CT. This finding suggests a prevalence of 1 per 3000 live births. Of the 47 patients, only eight (17%) had clinical manifestations: two had intracranial calcifications, four had retinal scars, one had an intracranial calcification and retinal scars, and one had hepatosplenomegaly with lymphoadenopathy. The testing was paid for by the patients' families who volunteered for the study and gave their informed consent. CONCLUSION: The 3-year prospective study using sensitive detection methods, reliable confirmation, and feedback from clinicians showed that CT has an extraordinarily high prevalence in Brazil, in fact the highest ever reported in the world. Although the long-term efficacy of treatment of CT has not been well documented, in view of the availability of reliable diagnostics, confirmation and monitoring, functional logistics, and networking for screening, the insidious nature of the sequelae and the very high prevalence of the disease, neonatal screening for CT should be considered an alternative to no screening at all.

A comprehensive screening program in South Brazil.

We present the experience and figures about a screening program in South Brazil carried on in Porto Alegre, capital of the Southern Brazilian State. We present the tests performed routinely in our laboratory, the prevalence of some diseases and tests for infectious diseases to be added in the most comprehensive regional program in our country.

Screening for congenital toxoplasmosis in Brazil.

Toxoplasmosis acquired at the end of the pregnancy can produce ocular and neurological sequelae. The detection of IgM anti-Toxoplasma gondii in dried blood spots of newborns is an important tool for early treatment and prevention. In this study we showed results of a pilot study about the prevalence of congenital toxoplasmosis in Brazil and concluded that this disease should be included in the menu of neonatal screening programs.

[Transient neonatal tyrosinemia: a frequent abnormality] / Tirosinemia neonatal transitória: uma alteração freqüente.

OBJECTIVE: To evaluate the frequency of transient neonatal tyrosinemia, with or without secondary hyperphenylalaninemia,observed through neonatal screening for metabolic disorders, andthe need of monitoration and intervention with drugs and/or specialdiet in selected cases. METHODS: 457.870 dried blood samples obtained by heel stickfrom 3 to 20 days old babies were qualitatively evaluated by aminoacid thin-layer chromatography. Positive cases were quantitativelyconfirmed in serum samples by fluorimetric measurement of tyrosineand phenylalanine. RESULTS: 1.231 dried blood samples displayed positive resultsfor tyrosine in the cromatographic evaluation. The fluorimetricserum analysis disclosed normal levels of tyrosine and phenylalaninein 822 patients. The remained 409 patients showed hightyrosine levels and were placed in three groups according to thetyrosine concentration. In 118 of these cases serum phenylalaninewas also increased. CONCLUCIONS: Transient neonatal tyrosinemia is a very frequentdisorder in neonates (1/372); in some cases very high levels werefound, not only of tyrosine but also phenylalanine. As this findingis not yet accepted as absolutely harmless, the monitoration of thissituation and the use of measures to lower the tyrosine and phenylalaninelevels should be considered by the pediatrician.