Age estimation by measuring open apices in teeth: a new formula for two samples of South African black and white children.

In this cross-sectional study, the accuracy of Cameriere's European formula was tested and a new specific model was developed for two samples of black and white South African children with known age and sex. For these purposes, 970 children of black South African ethnicity (girls 491, boys 479) and 974 with European ethnicity, living in South Africa (girls 493, boys 481), were retrospectively analyzed. The application of the European formula showed that there is a trend in the error estimates: the ages of the younger children are overestimated and those of the older children are underestimated, in both white and black children. A new model, based on the relationship between the apical width and the tooth length (maturity index) of the seven permanent mandibular teeth, was therefore constructed. The new developed equation for the South African population was able to explain 76% of total variance in white girls and 80% in white boys' subgroup. On the other side, the model explained 76% of total variance in black girls and 78% in the black boys' subgroup. The mean absolute error of the residuals (residuals = predicted age minus observed age) ranged from 0.718 to 0.769 years, with the interquartile range (IQRres) ranging from 1.19 to 1.31 years. Differently from the Cameriere's European formula, the plot did not tend to underestimate the chronological age significantly as the age increases. Cameriere's maturity index is reproducible in both samples of South African black and white children, for forensic purposes, and the Bayesian calibration approach is useful for a more accurate and precise estimation.

Third molar maturity index (I3M) for assessing age of majority: study of a black South African sample.

AIMS: The evaluation of the cutoff value of I3M = 0.08 for discriminating black South African minors from adults, and its relationship with chronological age. MATERIAL AND METHODS: A sample of 833 panoramic radiographs of healthy black South African subjects (500 females and 333 males), in the age range of 14 to 24 years (mean age 17.67 years in females and 17.42 years in males), was retrospectively evaluated. RESULTS: ICC values were 99.10% (95% CI 97.70 to 99.70%) and 99.20% (95% CI 98.00 to 99.60%), for the intra- and inter-observer reliability, respectively. I3M decreased as the real age gradually increased in both sexes. According to the logistic regression model, the variable sex was not significant when the probability that an individual is 18 years or older was calculated. The I3M = 0.08 was valuable in discriminating between adults and minors. The overall accuracy (ACC = fraction of accurately classified subjects) is 0.90 (95% CI 0.87-0.91); the proportion of correctly classified subjects (Se = sensitivity) is 0.80 (95% CI 0.76-0.84), and specificity (Sp) is 0.95 (95% CI 0.93-0.97). The PPV (predictive positive value) is 0.96 (95% CI 0.95-0.97), and the negative predictive value is 0.76 (95% CI 0.72-0.80). CONCLUSION: The results show that I3M is a valuable method to distinguish subjects who are around legal adult age in South Africa.

Is the third molar maturity index (I3M) useful for a genetic isolate population? Study of a Sardinian sample of children and young adults.

This work aims to assess the validity of the cut-off value (0.08) of the third molar maturity index (I3M) for discriminating minors from adults in Sardinian population. A sample of 336 digital panoramic radiographs of healthy Sardinian children and young minors (165 females and 171 males), aged between 15 and 23 years (mean age, 19.35 years in females and 18.80 years in males), was retrospectively evaluated. The left lower third molars were analysed by applying a specific cut-off value of 0.08 determined by Cameriere et al. in 2008. The reliability and reproducibility of the test was also studied: the intra-class correlation coefficients (ICC) were 0.91 (95% CI, 0.89-0.93) and 0.88 (95% CI, 0.86-0.90), for the intra- and inter-observer reliability, respectively. The I3M gradually decreased as the real age gradually increased in both sexes. According to the pooled results of the diagnostic test, the accuracy (ACC) was 0.86 (95% CI, 0.82-0.89); the proportion of correctly classified subjects (Se = sensitivity) was 0.82 (95% CI: 0.76-0.86); and specificity (Sp = specificity) was 0.95 (95% CI, 0.89-0.97). The positive predictive values (PPV) and the negative predictive values (NPVs) were 0.97 (95% CI, 0.94-0.99) and 0.70 (95% CI, 0.62-0.77). The LR+ and the LR- were 17.12 (95% CI, 7.27 to 40.36) and 0.19 (95% CI, 0.14 to 0.25). In spite of this, significant differences in the early mineralisation of the third molar were found between sexes as well as in the results of the diagnostic test, showing a better sensitivity in males than in females. The results showed that, although the third molar teeth are highly variable in development, and with differences between females and males as compare to other teeth, the I3M is a reliable method to distinguish between minors and adults even in such a genetic isolate population.

Herd- and cow-level risk factors associated with subclinical mastitis in dairy farms from the High Plains of the northern Antioquia, Colombia.

Mastitis is the main disease entity affecting dairy farms in the Colombian High Plains of northern Antioquia, Colombia. However, no previous epidemiologic studies have determined the characteristics that increase the risk of infection in this region, where manual milking is still the prevailing system of milking. A 24-mo longitudinal study was designed to identify the predominant mastitis pathogens and important herd- and cow-level risk factors. Monthly visits were made to 37 commercial dairy farms to collect herd- and cow-level data and milk samples. Herd size varied from 6 to 136 cows (mean 37.0, median 29). Herd-level factors included type of milking system (manual or mechanical) and a range of management practices recommended by the National Mastitis Council (Madison, WI) to prevent mastitis. Individual cow-level risk factors included parity, stage of lactation, breed, udder hygiene, and lameness. A logistic regression analysis was used to investigate associations between herd- and cow-level risk factors with the presence of subclinical mastitis and infection caused by Streptococcus agalactiae at the quarter level. A quarter was considered to have subclinical mastitis if it had a positive California Mastitis Test and was subsequently confirmed to have a somatic cell count of ≥200,000 cells/mL. Any cow with one or more quarters with subclinical mastitis was considered to have subclinical mastitis at the cow level. Using 17,622 cow observations, the mean prevalence of subclinical mastitis at the cow level was 37.2% (95% confidence interval: 31.2, 43.3) for the first month and did not substantially change throughout the study. The predominant microorganisms isolated from quarters meeting the subclinical mastitis definition were contagious pathogens, including Strep. agalactiae (34.4%), Corynebacterium spp. (13.2%), and Staphylococcus aureus (8.0%). Significant variables associated with subclinical mastitis risk at the quarter level included being a purebred Holstein cow, higher parity, and increased months in milk. Variables that were protective for mastitis risk included being a crossbreed cow and adequate premilking udder hygiene. Significant variables associated with Strep. agalactiae infection were higher parity, increased months in milk, and manual milking. Variables that were protective were postmilking teat dipping and adequate cleaning of the udder. The results highlight the importance of hygiene practices in contagious mastitis control in manually milked herds.

A cooperative interaction between LPHN3 and 11q doubles the risk for ADHD.

In previous studies of a genetic isolate, we identified significant linkage of attention deficit hyperactivity disorder (ADHD) to 4q, 5q, 8q, 11q and 17p. The existence of unique large size families linked to multiple regions, and the fact that these families came from an isolated population, we hypothesized that two-locus interaction contributions to ADHD were plausible. Several analytical models converged to show significant interaction between 4q and 11q (P<1 × 10(-8)) and 11q and 17p (P<1 × 10(-6)). As we have identified that common variants of the LPHN3 gene were responsible for the 4q linkage signal, we focused on 4q-11q interaction to determine that single-nucleotide polymorphisms (SNPs) harbored in the LPHN3 gene interact with SNPs spanning the 11q region that contains DRD2 and NCAM1 genes, to double the risk of developing ADHD. This interaction not only explains genetic effects much better than taking each of these loci effects by separated but also differences in brain metabolism as depicted by proton magnetic resonance spectroscopy data and pharmacogenetic response to stimulant medication. These findings not only add information about how high order genetic interactions might be implicated in conferring susceptibility to develop ADHD but also show that future studies of the effects of genetic interactions on ADHD clinical information will help to shape predictive models of individual outcome.

Analysis of the grafting process of PVP on a silicon surface by AFM and contact angle.

Silicon wafers have been silylated with VTMS (vinyltrimethoxysilane) and hydrolyzed. Subsequently, PVP (polyvinyl pyrrolidone) was grafted onto the silylated surface by two different techniques: the grafting-through (GT) and the grafting-onto techniques (GO). The measurement of contact angles along with the topography analysis by atomic force microscopy (AFM) has allowed monitoring the different stages of the process and the temporal evolution of polymer grafting. The results have demonstrated the feasibility of both methods of grafting but have shown that the GT method gives a higher density of polymer-grafted chains. The AFM technique in adequate liquid environments has been proven to permit the surface density of chains to be distinguished by both methods and to estimate the length of the resulting PVP chains.

Child brides: the age estimation problem in young girls.

The aim of this work is to study a sample of girls from 15 different countries using Third Molar Maturity Index (I3M ), to assess the probability that a girl has reached the legal age of 18 years. The studied sample consisted of 3228 Orthopantomograms of healthy female subjects from 15 different countries. The cut-off value of I3M = 0.08 was tested to discriminate adults (≥18 years) and minors (<18 years). X-ray images were processed by computer-aided drafting program ImageJ. The information on sensitivity and specificity of I3M coming from the 15 countries was pooled together using a bivariate Bayesian modeling approach. Specificity of the I3M test did not change when the country was considered, and its value remains greater than 85% for each studied country. This method is useful to estimate the age of the girls involved in suspected early marriage because of the high probability of correctly identifying a minor with similar results observed among tested populations.

[Dot blot for the diagnosis of porcine cysticercosis]. / Dot blot para el diagnóstico de la cisticercosis porcina.

The Taenia solium larva causes cysticercosis in pigs, as well as economic losses for farmers and taeniosis in humans, constituting a public health problem. Infested pigs must therefore be identified before they enter the food chain. To this end, a dot blot assay was developed for the immunodiagnosis of porcine cysticercosis. A study was made of 44 pigs from different areas of Colombia that had all tested positive to cysticercosis, both by necropsy and the Western blot technique. Another group was formed comprising 44 pigs that had all tested negative to Western blot and necropsy. After analysing these 88 samples to validate the diagnostic assay, the result was a sensitivity of 86.4% and a specificity of 93.2%. The dot blot assay proved useful in diagnosing porcine cysticercosis. As the assay is easy to use in laboratories in endemic areas, as well as under field conditions, it is also appropriate for epidemiological studies.

Validation of the third molar maturity index (I3M): study of a Dominican Republic sample.

This retrospective study aims to test the third molar maturity index (I3M) cut-off value of 0.08 for 18 years old in Dominican Republic population. Orthopantomograms of 513 subjects (284 females and 229 males) were evaluated, intra- and inter-observer agreement, ICC (intra-class correlation coefficient) values were 0.88% (95 % CI 0.86% to 0.91%), and 0.93% (95% CI 0.90% to 0.96%), for the intra- and inter-observer reliability, respectively. Accuracy in females was 0.96 (95% CI: 0.93-0.97); the sensitivity was 0.99 (95% CI: 0.96-0.99) and specificity was 0.92 (95% CI: 0.86-0.95). In males, the accuracy was 0.96 (95% CI: 0.93-0.98); the sensitivity was 0.94 (95% CI: 0.88-0.97) and specificity was 0.99 (95% CI: 0.95-0.99). The PPV (Positive Predictive Value) was 0.93 for females and 0.99 for males. The results of this study show that I3M can be used for discriminating adults from minors in Dominican Republic subjects around the legal age of 18 years old.

Performance of supported catalysts based on a new copper vanadate-type precursor for catalytic oxidation of toluene.

A new copper vanadate precursor with the formula NH(4)[Cu(2.5)V(2)O(7)(OH)(2)] . H(2)O was synthesized and deposited on two different supports, ZSM-5 and amorphous SiO(2), by a hydrothermal method or by mechanical mixture. The catalytic behaviour was evaluated in the total oxidation of toluene and the characterization was performed by H(2)-temperature-programmed reduction (H(2)-TPR), thermogravimetric analysis, elemental analysis, UV-vis diffuse reflectance spectroscopy and X-ray diffraction. It was found that the copper vanadate phase comprises two mixed oxides, one of them crystalline, the Ziesite phase, and the other one amorphous. The supported catalysts presented a content of copper vanadate phase of about 9-11 wt.%. The copper vanadate deposited on ZSM-5 by the hydrothermal method evidences the best performance in the oxidation of toluene. This behaviour can be associated with the smaller size and higher dispersion of the particles on the support, which was confirmed by their better reducibility and higher band gap energy value compared with the other series of studied catalysts.

Multiple furunculoid myiasis on the scalp of a child.

Cutaneous myiasis is easy to diagnose and treat if clinicians are aware of the condition. Because of widespread travel, physicians may encounter this infestation in patients living in geographical regions where the condition is rare. A child is presented with cutaneous myiasis that presented as furuncle-like nodules on the scalp. The larvae were identified as a stage of the bluebottle-like fly, Dermatobia hominis.

Sustained p16INK4a expression is required to prevent IR-induced tumorigenesis in mice.

Exposure of murine and human tissues to ionizing radiation (IR) induces the expression of p16INK4a, a tumor suppressor gene and senescence/aging biomarker. Increased p16INK4a expression is often delayed several weeks post exposure to IR. In this context, it remains unclear if it occurs to suppress aberrant cellular growth of potentially transformed cells or is simply a result of IR-induced loss of tissue homeostasis. To address this question, we used a conditional p16INK4a null mouse model and determined the impact of p16INK4a inactivation long-term post exposure to IR. We found that, in vitro, bone marrow stromal cells exposed to IR enter DNA replication following p16INK4a inactivation. However, these cells did not resume growth; instead, they mostly underwent cell cycle arrest in G2. Similarly, delayed inactivation of p16INK4a in mice several weeks post exposure to IR resulted in increased BrdU incorporation and cancer incidence. In fact, we found that the onset of tumorigenesis was similar whether p16INK4a was inactivated before or after exposure to IR. Overall, our results suggest that IR-induced p16INK4a dependent growth arrest is reversible in mice and that sustained p16INK4a expression is necessary to protect against tumorigenesis.

Investigation of MR image distortion for radiotherapy treatment planning of prostate cancer.

MR imaging based treatment planning for radiotherapy of prostate cancer is limited due to MR imaging system related geometrical distortions, especially for patients with large body sizes. On our 0.23 T open scanner equipped with the gradient distortion correction (GDC) software, the residual image distortions after the GDC were <5 mm within the central 36 cm x 36 cm area for a standard 48 cm field of view (FOV). In order to use MR imaging alone for treatment planning the effect of residual MR distortions on external patient contour determination, especially for the peripheral regions outside the 36 cm x 36 cm area, must be investigated and corrected. In this work, we performed phantom measurements to quantify MR system related residual geometric distortions after the GDC and the effective FOV. Our results show that for patients with larger lateral dimensions (>36 cm), the differences in patient external contours between distortion-free CT images and GDC-corrected MR images were 1-2 cm because of the combination of greater gradient distortion and loss of field homogeneity away from the isocentre and the uncertainties in patient setup during CT and MRI scans. The measured distortion maps were used to perform point-by-point corrections for patients with large dimensions inside the effective FOV. Using the point-by-point method, the geometrical distortion after the GDC were reduced to <3 mm for external contour determination and the effective FOV was expanded from 36 cm to 42 cm.

Medicinal plants from the "Sierra de Comechingones", Argentina.

Argentina is a country with both rich floral biodiversity and cultural diversity. Traditional herbal medicines are important in the health care of most people, and rely heavily on the use of indigenous plants. An ethnobotanical survey of the "Sierra de Comechingones" made over a 26-year period (1979-2005), indicated that 65 families and 149 different genuses were used in traditional medicines. The use of these medicines was observed to be widespread and prevalent over orthodox medicine. Medicinal native plants from this mountain range make up 31% of the total Argentina medicinal native flora. In addition, there are 15 endemic species that grow only in the region. The botanical name, popular uses, parts utilized, as well as the distribution of these medicinal plants from the "Sierra de Comechingones", Argentina, were summarized. Previous reports on phytochemical and biological activities in relation to cancer, antimicrobials and pesticides were also included.

[Description of an endogamous, multigenerational and extensive family with benign hereditary chorea from the Paisa community]. / Descripción de una genealogía endogámica, multigeneracional y extendida con corea hereditaria benigna, perteneciente a la comunidad Paisa.

INTRODUCTION: The benign chorea hereditary (BCH, OMIM 118700) represents a childhood movement disorder characterized by its early onset, a slow progressive course (mostly stable) and the absence of mental compromise, which contrast with the clinical features exhibited by the Huntington Disease. CASE REPORTS: Here we describe a multigenerational, extended and inbreed family belonging to a genetic isolate, the Paisa community from Antioquia Colombia, with seven children exhibiting clinical features of BCH. Even though some patients with BCH are heterozygous for a dominant mutation in the thyroid transcription factor-1 gene (TITF1), the pattern in this family resembles a recessive mode of inheritance, which suggests that genetic heterogeneity may be playing a role. CONCLUSION: Currently, linkage analysis is underway to determine if TITF1 is the gene responsible for this movement disorder in this family.

Anomalous transport of particle tracers in multidimensional cellular flows.

Advection of tracers is studied numerically in time-dependent, two-dimensional cellular flows and a time-independent, three-dimensional cellular flow field. Tracers in these flows follow trajectories that are either periodic or chaotic and mimic correlated Lévy flights. The probability density function of displacements for particles in the ordered regions of the flow follows a classical Gaussian dispersion process. The particle trajectories in the chaotic regions of the flow exhibit anomalous diffusion and the probability density function of displacements is well modeled by a time-fractional diffusion equation of order alpha. The overall process of particle dispersion is found to be controlled mainly by the chaotic regions within the flow field. From the perspective of Lagrangian dynamics our results indicate that the advection of particles in flow fields prone to exhibit chaotic advection is a combination of both classical, i.e., Gaussian, behavior and anomalous, i.e., non-Gaussian, diffusion.

Fractional diffusion model for force distribution in static granular media.

We present the results of a numerical and an experimental investigation of the probability distribution of normal contact forces in static packs of particles with two different hardnesses. Force distributions are computed and compared with existing models and experimental data. It is found that the probability distribution function of normal contact forces P(f) is well described by a semiempirical model derived from a fractional diffusion equation. This model reproduces most of the features common to force distributions observed in experimental and numerical studies including the finite value for P(f) as the forces tend to zero. The results indicate that the fractional model fits well both the numerical and experimental data over a wide range of particle deformations in contrast to the existing models. These results provide an insight into the physics of granular media and complement previous findings.

Effect of hydration of polyamide membranes on the surface electrokinetic parameters: surface characterization by x-ray photoelectronic spectroscopy and atomic force microscopy.

The surface and the solid/liquid interface of two polyamide membranes, one experimental (B0) and one commercial (NF45), have been characterized by X-ray photoelectronic spectroscopy (XPS), atomic force microscopy (AFM), and zeta potential, respectively. The surface roughness, determined by AFM data analysis, is different for the two membranes, and results show that the commercial NF45 membrane presents a much lower roughness than the experimental B0 membrane. XPS data indicate that the surface of membrane NF45 is similar to that of pure polyamide, while membrane B0 contains a considerable amount of impurities. The homogeneity in depth of both membranes was also studied by determining the composition profile at different analysis angles. Streaming potential along the membrane surface or tangential streaming potential (TSP) measurements with NaCl solutions at different concentrations were carried out with both membranes to determine the zeta potential and the electrokinetic surface charge density, and a correlation between membrane surface and interface parameters is made. Some differences in atomic concentrations of membrane surface elements and X-ray photoelectronic spectra of the samples used in TSP measurements and after a drying process at 90 degrees C for 24 h can be observed when they are compared with those for fresh membranes. Electrokinetic parameters for membrane NF45 (TSP, zeta potential, and surface electrokinetic charge density) obtained from three different series of measurements strongly decrease as a result of membrane use, but for membrane B0 they are practically independent of the number of measurements. This difference in the electrokinetic behavior of the two membranes has been related to the hydration process of the surface for each sample studied by XPS and AFM.

[Prevalence of Taenia solium antibodies in humans and in pigs in an endemic area of Colombia]. / Prevalencia de anticuerpos para Taenia solium en humanos y cerdos en una zona endémica colombiana.

INTRODUCTION: Cysticercosis (CC) caused by Taenia solium in humans and in pigs is endemic in many rural communities in developing countries. The use of Western blot assays (WB) to determine T. solium antibodies has become the best serological tool available to date for identifying positive individuals in field conditions. AIMS: The aim of this study was to determine the prevalence of T. solium antibodies in humans and in pigs in two rural communities in Antioquia, Colombia. PATIENTS, MATERIALS AND METHODS: Serological identification of humans and pigs with T. solium antibodies was performed using WB assays in two communities in Ituango, Antioquia. During the study, demographic variables, housing and health conditions were taken into account. Contingency tables were drawn up using c2 to compare the proportion of seronegative individuals and seropositive individuals with headache, fainting or convulsions. RESULTS: The prevalence of human and porcine CC obtained was 2.23 and 6.82% in Pascuita and 1.17 and 2.33% in Guacharaquero, both respectively. Of the 11 WB positive patients evaluated by imaging techniques, two individuals were found to have single calcifications in the TAC scan and RMI showed another to have an unspecified lesion. The prevalence of infection in humans and in pigs in two rural communities in the north of the district of Antioquia, Colombia, shows that CC is endemic and that steps must be taken to control it.

[Molecular genetic aspects of the susceptibility to develop idiopathic epilepsy]. / Aspectos genético-moleculares de la susceptibilidad para desarrollar epilepsia idiopática.

INTRODUCTION: There are more than 40 clinical types of epilepsy classified according to aetiology and/or mode of clinical onset. The term idiopathic epilepsy is reserved for cases with convulsions but no detectable structural lesions of the brain or neurological anomalies. DEVELOPMENT AND CONCLUSIONS: In spite of many studies confirming the importance of genetic factors in the occurrence of idiopathic epilepsy, these appear to be complex and probably involve a locus of variable expression or several loci with similar phenotype expression (epistaxis). Also, environmental factors have variable effects. In recent years the principal genes involved in susceptibility to develop epilepsy have been mapped. In this way one mitochondrial and three autosomic genes have been cloned as responsible for the development of certain forms of this disorder. Also several studies of genetic linkage have given evidence, sometimes inconsistent, regarding the influence of another five loci in the susceptibility to develop epilepsy (6p21.2, 6q23-25, 8q24, 8p, 10q). On occasions the same locus has been linked with different forms of epilepsy, and on other occasions one form of epilepsy has been shown to be linked to several loci.