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.

Evaluation of Cameriere and Willems age estimation methods in panoramic radiographs of Brazilian children.

The importance of age estimation in the forensic field is inherent to the process of establishing the biological profile of children, sub-adults and adults. The established profile might be useful for the identification of deceased victims or living individuals when it comes to age of legal interest. In parallel, age estimation is also investigated for clinical purposes, especially for the diagnosis of dental and bone maturation. Several studies were developed to provide accurate age estimation methods based on skeletal and dental development. This study aimed to apply and compare Cameriere's and Willems' methods for dental age estimation in a Brazilian sample. Two examiners performed image analysis and method application in 180 panoramic radiographs of Brazilian children aged 6-14 years old. The ages estimated with both methods revealed a good correlation with the chronological ages of Brazilian boys and girls. Cameriere's method showed a slight underestimation of 0.05 years for girls and 0.03 for boys. Willems' method, on the other hand, showed an overestimation of -0.47 years for girls and -0.39 for boys. Better age estimates were obtained combining the outcomes of both methods. In practice, Cameriere's and Willems' methods reached reliable outcomes and could be applied for dental age estimation purposes.

Single nucleotide polymorphisms in the growth hormone and IGF type-1 (IGF1) genes associated with carcass traits in Santa Ines sheep.

Polymorphisms in the growth hormone (GH) and IGF type-1 (IGF1) genes have been associated with the economic traits in farm animals, including BW of some sheep breeds. However, it remains unknown if these polymorphisms also affect carcass traits in sheep. Thus, we aimed to identify polymorphisms in the GH and IGF1 genes in Santa Ines sheep in order to describe their allelic and genotypic frequencies as well as to test the hypotheses that they are associated with the carcass traits. Fragments of 4550 bp (IGF1) and 1194 bp (GH) were sequenced in up to 191 lambs. In all, 18 polymorphisms were identified in the IGF1 and 21 in the GH gene. The IGF1 polymorphisms rs430457475, rs412470350, rs409110739 and rs400113576 showed an additive effect on the internal carcass length (-0.9265±0.4223), rump girth (-2.9285±1.1473), rib yield (-1.0003±0.4588) and neck weight (-0.0567±0.0278), respectively. In addition, the polymorphisms rs58957314 in the GH affected the rib weight (-0.4380±0.1272) and rib yield (-2.2680±0.6970), loin weight (-0.1893±0.0516) and loin yield (-0.9423±0.3259), palette weight (-0.2265±0.0779) and palette yield (-0.9424±0.4184), leg weight (-0.3960±0.1375), neck weight (-0.0851±0.0394) and carcass finishing score (-0.1700±0.0839). These results allow us to conclude that there are polymorphisms in the IGF1 and GH genes associated with carcass traits in Santa Ines sheep, which can provide important information for marker-assisted selection.

Chemical composition and morphology study of bovine enamel submitted to different sterilization methods.

OBJECTIVES: The morphology and chemical composition of enamel submitted to different sterilization methods was studied. METHODS: X-ray photoelectron spectroscopy (XPS), field emission gun scanning electron microscopy (FEG-SEM), and energy-dispersive X-ray spectroscopy (EDS) were performed to evaluate 50 bovine enamel specimens sterilized using four methods: microwaving (MI), gamma irradiation (GI), ethylene oxide (EO), and steam autoclave (SA). Non-sterilized specimens were used as control. RESULTS: XPS indicated that the concentration of P (phosphorus), CO3 (carbonate), and CO3/P was not changed in all groups. GI produced no significant change on elemental composition. SA produced the major decrease in calcium (Ca), Ca/P ratio, and increase in N (nitrogen). MI was found to decrease Ca, Ca/P ratio and O (oxygen), and increase in C (carbon) and N. EO produced decrease in Ca and O with increased C concentration. FEG-SEM revealed surface and in-depth morphological changes on SA specimens. Minor surface alterations were observed for EO and for MI groups, and no alteration was observed on GI group. EDS indicated no difference on elemental composition of enamel bulk among groups. CONCLUSIONS: SA produced mineral loss and morphological alterations on surface and in depth. MI and EO sterilization caused mineral loss showing only slight alteration on enamel surface. GI sterilization preserves the morphological characteristics of enamel. The sterilization methods could be classified from lower to high damage as GI < MI < EO < SA. CLINICAL RELEVANCE: This is a comprehensive comparative study where different methods for enamel sterilization were investigated in terms of chemical changes. The results presented here may help researchers to choose the most appropriate method for their research setting and purpose.

Age estimation by facial analysis based on applications available for smartphones.

BACKGROUND: Forensic Dentistry has an important role in the human identification cases and, among the analyses that can be performed, age estimation has an important value in establishing an anthropological profile. Modern technology invests for new mechanisms of age estimation: software apps, based on special algorithms, because there is not interference based on personal knowledge, cultural and personal experiences for facial recognition. MATERIALS AND METHODS: This research evaluated the use of two different apps: "How Old Do I Look? - Age Camera" and "How Old Am I? - Age Camera, Do You Look Like in Selfie Face Pic?", for age estimation analysis in a sample of 100 people (50 females and 50 males). Univariate and multivariate statistical methods were used to evaluate data. RESULTS: A great reliability was seen when used for the male volunteers. However, for females, no equivalence was found between the real age and the estimated age. CONCLUSION: These applications presented satisfactory results as an auxiliary method, in male images.

Efeitos da suplementação de colina sobre o desempenho de poedeiras comerciais / The effects of choline supplementation on the performance of laying hens

Os efeitos da suplementação de colina em dietas para poedeiras (Dekalb White) foram avaliados nas fases de cria/recria e de postura. O delineamento foi em esquema fatorial 2x5 (duas suplementações de colina de uma a 16 semanas de idade x cinco níveis de colina suplementada de 18 a 44 semanas de idade). Os níveis de colina utilizados foram 0, 200, 400, 600 e 800mg/kg para cada grupo. A suplementação de colina em frangas com uma a 16 semanas de idade não afeta o desempenho nem as características macroscópicas e histopatológicas dos fígados durante essa fase. Os efeitos dos níveis de suplementação de colina sobre o desempenho das galinhas na fase de postura dependem da suplementação ou não dessa vitamina nas fases de cria/recria; ou seja, as aves que recebem suplemento de colina nessas fases apresentam maior exigência no período de postura.

The effects of choline supplementation in diets for laying hens (Dekalb White) were evaluated from 1 to 44 weeks-old. The experimental design was a 2x5 factorial arrangement (two choline supplementations from one to 16 weeks of age - with and without choline supplementation vs. five levels of choline supplementation from 18 to 44 weeks old. The choline level used in the diet for each group was 0, 200, 400, 600 and 800mg/kg). Choline supplementation used in birds with 1 to 16 weeks of age does not affect the performance of pullets and no gross and histological changes were observed in the liver during this phase. The effects of the choline supplementation levels in the laying phase on the hens' performance depend on the supplementation with this vitamin from 1 to 16 weeks old. The results of the experiment showed that birds reared for laying need a higher level of choline supplementation from 1 to 16 weeks old or birds reared for laying receiving higher levels of choline supplementation during 1 to 16 weeks old will need a higher level of choline supplementation in the laying phase.

Efeito do armazenamento e da cantaxantina dietética sobre a qualidade do ovo fértil e o desenvolvimento embrionário / The effect of storage and dietary canthaxanthin on fertile egg quality and embryonic development

O presente experimento foi conduzido em lote de matrizes Cobb desde 46 até 60 semanas de idade. Os tratamentos foram definidos pelas dietas (com e sem adição de 6ppm de cantaxantina na dieta das matrizes) e pelos períodos de armazenamento dos ovos (três e sete dias), em delineamento inteiramente ao acaso, em arranjo fatorial 2x2 (duas dietas x dois períodos de armazenamento). A cantaxantina dietética elevou o escore de cor da gema de sete para 14. O armazenamento dos ovos por sete dias prejudicou a qualidade dos ovos, promoveu oxidação de ácidos graxos da gema e retardou o desenvolvimento embrionário.

This trial was done with Cobb broiler breeders. Treatments were defined by the diets (with and without 6ppm canthaxanthin added to broiler breeder diets) and periods of egg storage (three and seven days) in a completely randomized factorial 2 x 2 design (two diets x two periods of egg storage). The dietary canthaxanthin increased the yolk color score from 7 to 14. Egg storage for seven days reduced egg quality, promoted oxidation of yolk fatty acids and delayed embryonic development.

Comparison of Photodynamic Therapy versus conventional antifungal therapy for the treatment of denture stomatitis: a randomized clinical trial.

In this randomized clinical trial, the clinical and mycological efficacy of Photodynamic Therapy (PDT) was compared with that of topical antifungal therapy for the treatment of denture stomatitis (DS) and the prevalence of Candida species was identified. Patients were randomly assigned to one of two groups (n = 20 each); in the nystatin (NYT) group patients received topical treatment with nystatin (100,000 IU) four times daily for 15 days and in the PDT group the denture and palate of patients were sprayed with 500 mg/L of Photogem(®), and after 30 min of incubation, were illuminated by light emitting-diode light at 455 nm (37.5 and 122 J/cm(2), respectively) three times a week for 15 days. Mycological cultures taken from dentures and palates and standard photographs of the palates were taken at baseline (day 0), at the end of the treatment (day 15) and at the follow-up time intervals (days 30, 60 and 90). Colonies were quantified (CFU/mL) and identified by biochemical tests. Data were analysed by Fisher's exact test, analysis of variance and Tukey tests and κ test (α = 0.05). Both treatments significantly reduced the CFU/mL at the end of the treatments and on day 30 of the follow-up period (p <0.05). The NYT and PDT groups showed clinical success rates of 53% and 45%, respectively. Candida albicans was the most prevalent species identified. PDT was as effective as topical nystatin in the treatment of DS.

Evaluation of Candida albicans adhesion and biofilm formation on a denture base acrylic resin containing silver nanoparticles.

AIM: This study firstly evaluated the activity of a silver nanoparticle (AgNPs) solution against Candida albicans and then the effect of incorporation of AgNPs into a denture base acrylic resin on the material's hydrophobicity, C. albicans adhesion and biofilm formation. METHODS AND RESULTS: The AgNPs solution was synthesized by chemical reduction and characterized. Minimum inhibitory (MIC) and minimum fungicidal (MFC) concentrations for planktonic cells and sessile cells (MFCs) of the AgNPs solution against C. albicans were determined. Specimens (n = 360) of silver-incorporated acrylic resin at concentrations of 1000, 750, 500, 250 and 30 ppm were also prepared and stored in PBS for 0, 7, 90 and 180 days. Control was acrylic resin without AgNPs (0 ppm). After the storage periods, contact angles were measured and the specimens were used for C. albicans adherence (37°C; 90 min; n = 9) and biofilm formation (37°C; 48 h; n = 9) by XTT reduction assay. MIC, MFC and MFCs values were 3·98, 15·63 and 1000 ppm, respectively. Incorporation of AgNPs reduced the hydrophobicity of the resin. No effect on adherence and biofilm formation was observed. At 90 and 180 days of storage, there was significant increase in adherence and biofilm formation. CONCLUSIONS: Although the AgNPs solution had antifungal activity, no effect on C. albicans adherence and biofilm formation was observed after its incorporation into a denture base resin. SIGNIFICANCE AND IMPACT OF THE STUDY: The synthesized AgNPs solution is a promising antifungal agent, warranting investigations of more efficient methods of incorporation into denture base resins.

Suplementação de colina em dietas para frangos de corte machos na fase inicial de criação / Levels of supplementation of choline in diets for male broilers in initial phase

Foram avaliados os efeitos da suplementação de colina em dietas para frangos de corte sobre o desempenho produtivo e a composição da carcaça e do fígado e sobre as características macroscópicas e histopatólogicas do fígado na fase inicial de criação. Os tratamentos foram definidos pela suplementação de colina - zero, 100, 200, 300 e 400mg de colina/kg de ração, durante o período de criação de um a 21 dias de idade. As dietas experimentais, formuladas à base de milho, farelo de soja e farinha de carne, foram isonutritivas, com exceção dos níveis de colina. O delineamento experimental utilizado foi o inteiramente ao acaso, e a estimativa da suplementação de colina foi avaliada pelos modelos de regressão. A suplementação de colina apresentou efeito linear significativo para conversão alimentar, e as demais características avaliadas não foram influenciadas pela suplementação. A suplementação de 400mg colina/kg de ração melhora a conversão alimentar de frangos de corte aos 21 dias de idade.

The effects of supplemental levels of choline on performance, carcass composition and gross and histopatology characteristics of the livers in the initial phase in diets for broiler chickens were evaluated. The treatments were defined by the levels of choline supplementation (zero, 100, 200, 300 and 400mg choline/kg diet). The period of creation was one to 21 days-old. Diets formulated based on corn, soybean meal and meat meal are constituted by isonutrient except the levels of choline. The experimental design was completely randomized and the estimation of choline supplementation was evaluated by regression models. The levels of choline supplementation showed a significant linear effect for the F test (P<0.05). Values for feed and other parameters were not influenced by supplementation (P>0.05). The supplementation of 400 mg choline/kg diet improves feed conversion of broilers at 21 days old.

Teores de glicina+ serina total em dietas de baixa proteína bruta para de frangos de corte de 22 a 35 dias de idade / Total glycine+serine level in low crude protein diets of broiler chickens from 22 to 35 days of age

O experimento foi realizado em delineamento inteiramente ao acaso para avaliar os efeitos de diferentes teores de glicina + serina (gli+ser) total em dietas de baixa proteína bruta (PB) sobre o desempenho e as características de carcaça de frangos de corte de 22 a 35 dias de idade. Foram utilizadas 750 aves distribuídas em cinco tratamentos, cinco repetições e 30 aves por unidade experimental. As aves foram alimentadas até os 21 dias com uma dieta comum de acordo com as exigências. A partir do 21º dia, as dietas utilizadas continham 17 por cento de PB e níveis de gli+ser de 1,50; 1,75; 2,00 e 2,25 por cento; a dieta-controle continha 21 por cento de PB. O teor de gli+ser teve efeito linear sobre a conversão alimentar e não sobre as demais variáveis de desempenho. Não houve efeito de tratamento sobre os rendimentos de carcaça e cortes. Houve efeito linear decrescente do teor de gli+ser sobre a matéria seca da carcaça.

A completely randomized experimental design was carried out to evaluate the effects of total glycine+serine (gly+ser) levels in low crude protein (CP) diets on performance and body composition of male broiler from 22 to 35 days of age (growing phase). A total of 750 broilers were randomly allotted to five treatments and five replicates of 30 chickens per replication. The birds were fed from 1 to 21 days of age, a common diet formulated to meet bird requirements in all nutrients. From 21 days the diets contained 17 percent CP and gly+ser levels of 1.50; 1.75; 2.00 and 2.25 percent; and a control diet with 21 percentCP. The gly+ser levels showed linear effect on feed: weight gain ratio during the growing phase. There was no effect of gly+ser level on carcass or main carcass part yields. Increasing levels of gly+ser decreased linearly the carcass dry matter content.

Evaluation of fungal adherence to plasma-modified polymethylmethacrylate.

There is a propensity for fungal adherence to the polymethylmethacrylate used for making denture bases. Therefore, this study investigated whether surface modifications with plasma treatments would reduce the adherence of Candida albicans to a denture base resin. Samples (n = 180) with smooth and rough surfaces were made and divided into five groups: control - non-treated; experimental groups - submitted to plasma treatments to obtain surfaces with different hydrophobicities (Ar/50 W; ArO(2) /70 W; AAt/130 W) or with incorporated fluoride (Ar/SF(6) 70 W). Contact angles were measured immediately after treatments and after samples were immersed in water for 48 h. For each group, half the samples were incubated with saliva before the adherence test. The number of adhered C. albicans was evaluated by counting after crystal violet staining. The plasma treatments were effective in modifying the polymethylmethacrylate surface. However, there was a significant alteration in the contact angle measured after immersion in water. No statistically significant difference in the adherence of C. albicans was observed between the experimental and control groups, irrespective of the presence or absence of saliva, and surface roughness.

Disinfection of bovine enamel by microwave irradiation: effect on the surface microhardness and demineralization/remineralization processes.

Enamel specimens need to be disinfected before being used in intraoral appliances and the disinfection method must not affect the integrity of the tooth. This study evaluated the effectiveness of microwave bovine enamel disinfection and its effect on the surface microhardness (SMH) and cross-sectional microhardness (CSMH) of sound, demineralized and remineralized enamel. Forty enamel specimens were divided into two groups (n = 20): control (nonirradiated) and microwave. Microwave specimens were immersed in water and irradiated (650 W/3 min). Specimens were incubated at 37 degrees C for 7 days under aerobic and anaerobic conditions. An aliquot was removed for counting, plated at serial dilutions on blood agar plates, which were incubated aerobically and anaerobically. The colony-forming units were calculated. Other 20 enamel specimens (4 x 4 mm) were embedded in acrylic resin, polished and sliced into two halves: one of the fragments was reserved as control while the other was microwaved. SMH and CSMH of sound enamel were analyzed for both groups. The CSMH was further evaluated after demineralization and remineralization cycles. The Knoop integral (DeltaKI) was also calculated. Data were analyzed statistically by paired Student's t test (alpha = 0.05). While control specimens showed microbial growth, those microwaved were disinfected. There were no significant differences in SMH, CSMH and DeltaKI between the control and microwave groups. Microwave irradiation for 3 min at 650 W was effective for the complete disinfection of bovine enamel specimens without affecting the SMH and CSMH of sound, demineralized and remineralized enamel.

Association between decreased vitamin levels and MTHFR, MTR and MTRR gene polymorphisms as determinants for elevated total homocysteine concentrations in pregnant women.

OBJECTIVES: To examine the association between methylenetetrahydrofolate reductase (MTHFR) (C677T and A1298C), methionine synthase (MTR) A2756G and methionine synthase reductase (MTRR) A66G gene polymorphisms and total homocysteine (tHcy), methylmalonic acid (MMA) and S-adenosylmethionine/S-adenosylhomocysteine (SAM/SAH) levels; and to evaluate the potential interactions with folate or cobalamin (Cbl) status. SUBJECTS/METHODS: Two hundred seventy-five healthy women at labor who delivered full-term normal babies. Cbl, folate, tHcy, MMA, SAM and SAH were measured in serum specimens. The genotypes for polymorphisms were determined by PCR-restriction fragment length polymorphism (RFLP). RESULTS: Serum folate, MTHFR 677T allele and MTR 2756AA genotypes were the predictors of tHcy levels in pregnant women. Serum Cbl and creatinine were the predictors of SAM/SAH ratio and MMA levels, respectively. The gene polymorphisms were not determinants for MMA levels and SAM/SAH ratios. Low levels of serum folate were associated with elevated tHcy in pregnant women, independently of the gene polymorphisms. In pregnant women carrying MTHFR 677T allele, or MTHFR 1298AA or MTRR 66AA genotypes, lower Cbl levels were associated with higher levels of tHcy. Lower SAM/SAH ratio was found in MTHFR 677CC or MTRR A2756AA genotypes carriers when Cbl levels were lower than 142 pmol/l. CONCLUSIONS: Serum folate and MTHFR C677T and MTR A2576G gene polymorphisms were the determinants for tHcy levels. The interaction between low levels of serum Cbl and MTHFR (C677T or A1298C) or MTRR A66G gene polymorphisms was associated with increased tHcy.

Clinical evaluation of abutment teeth of removable partial denture by means of the Periotest method.

Prosthodontics should be one of the means of establishing conditions for the maintenance of periodontal health. The forces applied to the abutment teeth and their effects are very important considerations in the design and construction of the removable partial dentures. This 6-month follow-up clinical study evaluated the degree of mobility of abutment teeth of distal extension and tooth supported removable partial dentures by using Periotest. Two types of clasp design were selected for evaluation. In cases with unilateral and bilateral distal-extension, a clasp design including a T clasp of Roach retentive arm, a rigid reciprocal arm and a mesial rest were used. For the abutments of tooth-supported removable partial dentures, a second clasp design with a cast circumferential buccal retentive arm, a rigid reciprocal clasp arm and a rest adjacent to the edentulous ridges was selected. A total of 68 abutment teeth was analysed. Periotest values were made at the time of denture placement (control) and at 1, 3 and 6 months after the denture placement. The statistical analysis was performed using Friedman test. All analysis was performed at a 0.05 level of significance. The results revelled that no significant changes in tooth mobility were observed during the 6-months follow-up (P > 0.05). In conclusion, our findings suggest that adequate oral hygiene instructions, careful prosthetic treatment planning and regular recall appointments play an important role in preventing changes in abutment tooth mobility caused by removable partial denture placement.

Development and application of methods for determination of residual monomer in dental acrylic resins using high performance liquid chromatography.

Two high-performance liquid chromatographic methods for determination of residual monomer in dental acrylic resins are described. Monomers were detected by their UV absorbance at 230 nm, on a Nucleosil C18 (5 microm particle size, 100 A pore size, 15 x 0.46 cm i.d.) column. The separation was performed using acetonitrile-water (55:45 v/v) containing 0.01% triethylamine (TEA) for methyl methacrylate and butyl methacrylate, and acetonitrile-water (60:40 v/v) containing 0.01% TEA for isobutyl methacrylate and 1,6-hexanediol dimethacrylate as mobile phases, at a flow rate of 0.8 mL/min. Good linear relationships were obtained in the concentration range 5.0-80.0 microg/mL for methyl methacrylate, 10.0-160.0 microg/mL for butyl methacrylate, 50.0-500.0 microg/mL for isobutyl methacrylate and 2.5-180.0 microg/mL for 1,6-hexanediol dimethacrylate. Adequate assay for intra- and inter-day precision and accuracy was observed during the validation process. An extraction procedure to remove residual monomer from the acrylic resins was also established. Residual monomer was obtained from broken specimens of acrylic disks using methanol as extraction solvent for 2 h in an ice-bath. The developed methods and the extraction procedure were applied to dental acrylic resins, tested with or without post-polymerization treatments, and proved to be accurate and precise for the determination of residual monomer content of the materials evaluated.

DNA-flow cytometry of 207 pituitary adenomas: ploidy, proliferation, and prognosis.

The principal factors involved in pituitary adenoma formation are unknown. DNA-flow cytometry is a useful study providing an estimation of a tumor proliferative rate. In this study, DNA-flow cytometry was performed to evaluate its capability to both assess prognosis and predict recurrence. Two hundred and seven fresh pituitary adenoma specimens were assessed by flow cytometry. Pre-operative endocrine function, previous medical treatment, radiographic appearance, surgical findings and immunohistochemistry were recorded for each patient. Patient outcomes were assessed at a mean follow-up of 5.3 +/- 3.1 yr. Endocrinologically inactive pituitary adenomas were predominantly euploids (50.8%). The highest proliferation rates occurred in Nelson's syndrome and the lowest in Cushing's disease. A significant difference in proliferation was observed with prolactinomas and acromegaly when a medical treatment was performed before primary surgery. Massive histological invasiveness was directly associated with a significant increase in proliferation rate. Radiotherapy did not affect the recurrence rate (4.4%) statistically. In conclusion, DNA-flow cytometry was found to be useful for determining ploidy and obtaining an overview of cell cycle status. It was helpful in identifying patients requiring closer follow-up, such as those with invasive adenomas and Nelson's syndrome. No single parameter revealed by DNA-flow cytometry could predict tumor prognosis or recurrence in the follow-up of 7.5 +/- 1.3 yr.

Temporal and spatial variation on heavy metal concentrations in the oyster Ostrea equestris on the northern coast of Rio De Janeiro State, Brazil.

Heavy metal (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) concentrations were determined by ICP-AES in Ostrea equestris from three beaches (Barra do Furado, Buena, and Ponta do Retiro) on the northern coast of Rio de Janeiro State. The average concentration was 0.8 +/- 0.18, 0.4 +/- 0.21, 58 +/- 25.6, 249 +/- 52.3, 11 +/- 1.31, 0.55 +/- 0.16, 0.13 +/- 0.11, and 1131 +/- 321 microg x g(-1) dry weight for Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn respectively. Significant spatial variation (p < 0.05) between the samples areas occurred for Cr, Pb, and Zn with higher values in Barra do Furado; and for Cu in Ponta do Retiro. Significant temporal variations (p < 0.05) were observed for all metals except Cu. Temporal variability may be related to changes in the inputs of metals associated with suspended particles. Concentrations were similar to those found in areas under low pollution impact, except for Zn, the high concentrations of which probably reflect the physiological characteristics of these organisms.

Analysis of secretory, immunostaining and clinical characteristics of human "functionless" pituitary adenomas: transdifferentiation or gonadotropinomas?

In this study, the central technique of in vitro culture has been used to further investigate whether LH/FSH-expressing, but clinically "functionless" pituitary adenomas are gonadotropinomas or whether their hormone secretion is due to transdifferentiation events. 664 "functionless" pituitary adenomas were examined for hormone secretion by in vitro culture and for hormone content by immunostaining. The results were correlated with the clinical findings. 40 % of the tumours (n = 263) secreted at least one of the gonadotropins alone, 8 % (n = 53) exhibited various patterns of anterior pituitary hormones, whilst the remaining 52 % of tumours were not associated with any hormone. In the secretory tumours, immunostaining revealed only a few scattered hormone-containing cells (5 to 15 %). Mild hyperprolactinaemia was observed in some cases, presumably because of pressure effects of the tumours. The majority of the patients suffered clear cut hypopituitarism (p < 0.05). Pre-operatively, gonadotropin hypersecretion was observed in 3 cases, but only one of these secreted hormones in culture. Interestingly, a higher proportion of tumours removed from patients with hypopituitarism showed secretory activity in vitro than those tumours removed from patients showing no hormonal dysfunction or hyperprolactinaemia. We conclude that the term "gonadotropinoma" to describe functionless pituitary tumours associated with LH and/or FSH secretion is a misnomer, because the presence of LH and/or FSH confirmed by in vitro methods in the present series is a result of only a few scattered cells. We suggest that primary pituitary tumour cells differentiate into a secretory type (transdifferentiation), possibly in response to altered serum hormone levels such as decreased steroids. Further work is required to identify the factors which trigger the altered cells' characteristics.

Temporal and spatial variation on heavy metal concentrations in the oyster Ostrea equestris on the northern coast of Rio de Janeiro State, Brazil

Foram determinadas as concentrações de metais pesados (Cd, Cr, Cu, Fe, Mn, Ni, Pb e Zn) na ostra Ostrea equestris em três praias (Barra do Furado, Buena e Ponta do Retiro) da costa norte do Estado do Rio de Janeiro utilizando-se ICP-AES. As concentrações médias foram 0,8 ± 0,18; 0,4 ± 0,21; 58 ± 25,6; 249 ± 52,3; 11 ± 1,31; 0,55 ± 0,16; 0,13 ± 0,11; e 1131 ± 321 µg.g-1 de peso seco para Cd, Cr, Cu, Fe, Mn, Ni, Pb e Zn, respectivamente. Entre as áreas amostradas, houve variação espacial significativa (p < 0,05) das concentrações de Cr, Pb e Zn com maiores valores na Barra do Furado, e de Cu apenas em Ponta do Retiro. Foi observada variação temporal significativa (p < 0,05) para todos os metais, exceto Cu. Essa variabilidade provavelmente está associada a entradas de metais associados ao material particulado em suspensão. Os bivalves apresentaram concentrações similares àquelas encontradas em áreas com baixo impacto de contaminação por metais, exceto para Zn, cujo acúmulo provavelmente está associado às características fisiológicas desses organismos.