Oral health of schoolchildren residing in areas with or without water fluoridation in Sorocaba,São Paulo State,Brazil

This study describes dental caries data and fluorosis in seven municipalities in the Sorocaba region, S o Paulo State, Brazil, comparing those with fluoridated as opposed to non-fluoridated water. Criteria were those proposed by the World Health Organization (WHO, 1997), adapted by the School of Public Health, University of S o Paulo. The sample was selected at random, without replacement, and was calculated by age, accepting a design error of 2 and a sampling loss of 20% (n = 96 per age). There were six trained examiners, with accepted agreement percentage above 89% for all variables. In the Sorocaba region, the dmft index in 5 year-old children was 3.1, and 37.6% were caries-free (DMFT = 0). At age 12, 32.3% were caries-free (DMFT = 0), and the DMFT index in the region was 2.6, thus characterizing the area as having a low prevalence of caries. In areas with fluoridated water, the proportion of caries-free children at 12 years was higher than in those without fluoridated water (p = 0.019), and the DMFT was lower (p = 0.001). Prevalence of fluorosis at age 12 was 12.7% in the Sorocaba area and did not pose a public health problem according to the community fluorosis index (CFI).     

Analogic versus digital mammographic examination a radiological study of mammary microcalcifications on 52 surgical samples

PURPOSE: Digital mammography is known to have lower spatial resolution compared to conventional analogic mammography. The aim of this study was to evaluate whether this physical feature could compromise the perception of microcalcifications in radiological findings. MATERIALS AND METHODS: Fifty-two surgical samples of non-palpable breast lesions with microcalcifications were imaged using both techniques. The images were examined by four different radiologists. Data processing was limited to comparing the number of microcalcifications found on the conventional and digital images, in both standard and magnified modality. The cases were classified into 3 groups according to the number of calcifications demonstrated in the surgical sample: less than 10, 10 to 30, and more than 30. The differences in the count of microcalcifications with the two acquisition modalities were evaluated with the Kappa test. In order to compare the differences we synthesised by percentage those cases exhibiting a larger or lesser number of calcifications. RESULTS: The Kappa test was 0.546 in standard analogic vs standard digital, 0.582 in magnified analogic vs magnified digital, 0.828 in standard analogic vs magnified analogic and 0.492 in standard digital vs magnified digital. The most significant results were observed on comparing the magnifications produced with the two modalities: in 25% of cases, digital magnification detected more calcifications than did traditional magnification. The number of cases where standard digital images allowed the detection of more calcifications than standard analogic images was significant, although less important (17.8%). CONCLUSIONS: The study was able to provide data that confirm the overall equivalence of the two techniques, as far as subtle mammographic findings (such as microcalcifications) are concerned. In particular, as applied to the series we examined, there is a cautious advantage in favour of the digital technique. More clinical studies, on larger series, will be necessary for a further and more thorough comparison of the two techniques, so that the results might be consistently useful in clinical practice.     

Tc-99m exametazime-labeled leukocyte scans in the study of infections in skull neurosurgery

Diagnosis and follow-up of skull infections are usually performed by neurologic examination, laboratory tests and instrumental diagnostic methods such as computed tomography (CT) and magnetic resonance imaging (MRI). These have, however, shown some limitations for specificity. The aim of the current study was to evaluate the overall contribution of Tc-99m exametazime-labeled leukocyte imaging scan Tc-99m hexamethylpropyleneamine (HMPAO) labeled white blood cells (WBC) in the diagnosis and management of infections in skull neurosurgery. Thirty-four patients were subdivided into 4 groups on the basis of the suspected pathology: intracerebral lesions on CT or MRI (group A, n = 20), suspected postsurgical infections (group B, n = 6), suspected deep infection of the surgical wound (group C, n = 4), and suspected infection of the ventriculoperitoneal shunt (group D, n = 4). All patients underwent CT, MRI, and Tc-99m HMPAO WBC imaging. Patients in group C also underwent bacteriologic and culture examinations of wound secretions if present. In positive cases in group A, Tc-99m HMPAO WBC imaging was repeated. The scintigraphic results were compared with histologic findings in patients who underwent surgery and with the results of a 12-month clinical follow-up in the remaining patients. Tc-99m HMPAO WBC scans correctly detected the infections in all groups. Furthermore, such imaging proved to be able to document recovery from the disease in all of the assessed cerebral abscesses. This study may have an important role both in the diagnosis and in the management of infections in skull neurosurgery, which, it is hoped, will be confirmed in the future.     

Mechanical asphyxia by three different mechanisms

We report the case of death of a 75-year-old Caucasian woman, produced by three different ways of mechanical asphyxia: smothering and strangulation by hand and traumatic asphyxia by thoracic compression. All these criminal offences were carried out by one single assailant who compressed the mouth and the nose of the victim with the left hand, squeezed her neck with the right hand and pressed her thorax with the knees.     

Organotypic slices in vitro: repeated,same-cell,high-resolution tracking of nuclear and cytoplasmic fluorescent signals in live,transfected cerebellar neurons by confocal microscopy

The culture of organotypic slices for the purposes of tracking dynamic cellular events within the same live cell at high resolution, as a function of development in vitro has not been previously reported. The present study was undertaken to define the conditions most suitable for both the in vitro organotypic development of Purkinje neurons in cerebellar slices of neonatal mice, and the repeated visualization of nuclear signals within such cells. Slices of cerebella were maintained on 25 mm diameter, collagen-coated Anodisc membranes, placed in six-well plates and raised to the air-medium interface by use of glass fibre filter supports. This system permits cultures to be repeatedly observed both by phase contrast microscopy and, upon biolistic transfection, by laser confocal microscopy using 40x, 60x, and 100x water-immersion objectives, at high resolution. Upon co-transfection with two plasmids, differentiation of the same transfected Purkinje neurons was followed across in vitro development for periods of up to 10 days. Despite the relative thickness of the slice culture, even small, punctate, nuclear signals, were detectable. The results show that Purkinje neurons in cerebellar slices explanted from postnatal day 2 mice, developed cytotypically, although some were ectopically located. In contrast, Purkinje neurons in slices from postnatal day 6 cerebella developed in an organotypic manner. It is concluded that this culture system serves as an ideal tool for applications in experimental biology where high resolution tracking of cellular signals, over extended time periods, is of interest.     

Folate and vitamin E deficiency impair cognitive performance in mice subjected to oxidative stress: differential impact on normal mice and mice lacking apolipoprotein E

One factor contributing to the age-related decline in cognitive performance is increased oxidative stress, that can arise from environmental, nutritional, and/or genetic compromise. Folate deficiency has been linked to several age-related neurodegenerative conditions, including Alzheimer's disease (AD), at least in part by increasing oxidative stress. Folate deficiency also potentiates the impact of other known risk factors for AD. Adecrease in function of apolipoprotein E (ApoE), is associated with increased oxidative stress and is a risk factor for AD. We tested the combined impact of dietary deficiencies in folate and vitamin E, coupled with exposure to high dietary iron as a pro-oxidant, on cognitive performance in normal and ApoE-/- mice by monitoring the percent alternation in passive Y and T maze tests. Both normal and ApoE-/- mice displayed some cognitive impairment when deprived of folate and vitamin E and exposed to iron, but ApoE-/- mice were more severely affected. These findings highlight the potential combined impact of dietary deficiencies and genetic predisposition to neurodegeneration. They further leave open the possibility that one or more risk factors may remain latent, and neurodegeneration may ensue only following augmentation by one or more additional traumatic events or conditions.     

Induction of cell cycle arrest and apoptosis in human cervix carcinoma cells during therapy by cisplatin

The aim of the therapy of human malignancies is the inhibition of cell proliferation and/or induction of apoptosis. We studied the kinetics of the morphological and biochemical changes in HeLa cells during chemotherapy by cisplatin (CP). Apoptosis was evaluated by scoring of cells exhibiting changes characteristic for early and late stages of apoptosis as determined by Hoechst 33258 staining and by examination of positive reaction for activated caspase-3. Expression and intracellular localization of distinct proteins was analyzed by immunoblotting of subcellular fractions and segregation of nucleoli by immunocytochemistry. Chromatin fragmentation characteristic for apoptosis was observed in single cells after 3h cisplatin. A strong cytoplasmic accumulation of cytochrome C detected by immunoblotting 6h post-treatment was accompanied by an activation of caspase-9. Neither inhibition of cell division nor blocking of DNA replication preceded the onset of apoptosis. Our results show that after short treatment by CP, cell proliferation and apoptosis concomitantly occurred.