Diagnostic Cytochrome b gene profiles for the identification of paca (Cuniculus paca) bushmeat: implications for the monitoring of illegal hunting and wildlife trade

Paca (Cuniculus paca Linnaeus, 1766) is the second largest rodent found in Brazil. The quality of the meat and a long tradition of hunting have contributed to the decline of the natural populations of this species. Hunting of paca is strictly prohibited in Brazil, but in spite of this restriction, no forensic tools are available for the identification of the meat. We describe an efficient method, based on single nucleotide polymorphisms of the cytochrome b gene, that can be used to differentiate biological material derived from paca from those of domestic species commonly used as sources of meat. The identification of the presence of C. paca in the samples was 100% reliable.

Post-activation Potentiation in Propulsive Force after Specific Swimming Strength Training

We investigated whether a conditioning activity (8×12.5 m with 2.5 min-interval using both hand paddles and parachute) induced post-activation potentiation in swimming propulsive force and whether a swimmer's force level affected a post-activation potentiation response. 8 competitive swimmers (5 males and 3 females, age: 18.4±1.3 years; IPS=796±56) performed a 10 s maximum tethered swimming test 8 and 4 min before (the highest value was considered as PRE), and 2.5 and 6.5 min after (POST1 and POST2, respectively) the conditioning activity. Rate of force development was not affected, but peak force in POST1 (p=0.02) and impulse in both POST1 (p=0.007) and POST2 (p=0.004) were reduced. Possibly the conditioning activity induced greater fatigue than post-activation potentiation benefits. For instance, the number of repetitions might have been excessive, and rest intervals between the conditioning activity and POST1 and POST2 were possibly too short. There were positive correlations between PRE peak force and changes in peak force and rate of force development. Although conditioning activity was detrimental, positive correlations suggest that weaker swimmers experience a deterioration of performance more than the stronger ones. This conditioning activity is not recommended for swimmers with the current competitive level before a competitive event.

[Descriptive analysis of pelvic asymmetry in an asymptomatic population]

INTRODUCTION

Pelvic tilt is clinically assessed based on its relationship with spinal conditions, but there is little evidence from the asymptomatic-population for comparison purposes.

OBJECTIVE

To analyze an asymptomatic population focusing,on pelvic asymmetries using photogrammetry.

MATERIAL AND METHODS

92 subjects (18-35 years old) underwent marking of the anterior and posterior iliac spines and were photographed. Alcimage software was used to measure the pelvic tilt angle. Other tests included: the Kolmogorov normality test, t test, Wilcoxon test, and Pearson coefficient to measure the correlation.

RESULTS

11.96% of males had anteversion and 34.78% normality; 38.04% of females had anteversion and 15.22% normality. Angles between iliacs for bilateral tilt showed no difference, but a difference was seen with the predominance of one side. For unilateral tilt a difference between illacs was seen. Good correlation of predominance versus anteversion was observed, and correlation was poor for side angles. The rest showed a weak or non-significant correlation.

CONCLUSION

Tilt cannot be used individually to characterize pelvic dysfunction or pathology.

Age affects the laying performance and egg hatchability of red-legged partridges (Alectoris rufa) in captivity

Red-legged partridge breeders are frequently reared in captivity with the aim of producing fertile eggs and chicks. However, little is known regarding the role of breeder age on fertility and egg production performance. Therefore, we investigated the effects of breeder age on egg size and shape, flock reproductive performance, fertility, hatchability, and embryonic mortality. In experiment 1, the effects of breeders' age on fertility, hatchability of eggs, and embryo mortality were evaluated. We found that partridge breeder age significantly affected the onset of egg laying, egg production, number and proportion of settable eggs, hatchability, and fertility. Specifically, 1-yr-old females laid their first egg 1 wk later than 2, 3, or 4-yr-old birds. Furthermore, 2-yr-old females produced a significantly higher number of settable and fertile eggs than other females (53.0 vs. 46.4 to 48.5) and had a lower incidence of embryo mortality. In experiment 2, we examined the effects of breeder age, egg size, and egg shape on egg hatchability. We found that small eggs (<17.6 g) had a significantly lower hatchability than medium (17.6 to 18.9 g) or large eggs (>18.9 g). However, we did not observe any significant correlation between egg shape and hatchability. These results suggest that red-legged partridge breeders attain maximum reproductive capacity at 2 yr of age and produce fewer eggs with lower weight and hatchability thereafter.

Sequential hair mercury in mothers and children from a traditional riverine population of the Rio Tapajós, Amazonia: seasonal changes

Riverine populations of the Brazilian Amazon depend on fish for their principal source of protein, which changes in availability with seasonal fluctuations in the aquatic ecosystem. We report seasonal (high and low waters) and interannual changes in total mercury and methylmercury concentrations in hair of subsistence fish-eaters from a traditional riverine village on the banks of the Rio Tapajós in the Brazilian Amazonia. Retrospective exposure assessment was conducted from hair concentrations in segments representative of 2 years. A total of 32 mothers and their 51 children were studied. They reported high fish consumption (4-14 times a week). Ranges of total mercury and methylmercury concentrations in hair were 1.0-51.0 and 0.5-41.4microgg(-1), with means of 12.4 and 10.2microgg(-1), respectively. The relative mean value for methylmercury was 80%. There was a significant correlation between mothers and children for both total-Hg (r=0.4826; P=0.003) and methyl-Hg (r=0.5214; P=0.004). Mercury concentrations along hair strands of individuals showed significant variation coinciding with seasonal high and low waters. The changes in the aquatic environment impacted fish species availability, which is reflected in the total and MeHg concentrations in hair.

Profile of micronucleus frequencies and DNA damage in different species of fish in a eutrophic tropical lake

Lake Paranoá is a tropical reservoir for the City of Brasilia, which became eutrophic due to inadequate sewage treatment associated with intensive population growth. At present, two wastewater treatment plants are capable of processing up to 95% of the domestic sewage, thereby successfully reducing eutrophization. We evaluated both genotoxic and cytotoxic parameters in several fish species (Geophagus brasiliensis, Cichla temensis, Hoplias malabaricus, Astyanax bimaculatus lacustres, Oreochromis niloticus, Cyprinus carpio and Steindachnerina insculpita) by using the micronucleus (MN) test, the comet assay and nuclear abnormality assessment in peripheral erythrocytes. The highest frequencies of MN were found in Cichla temensis and Hoplias malabaricus, which were statistically significant when compared to the other species. However, Steindachnerina insculpita (a detritivorous and lake-floor feeder species) showed the highest index of DNA damage in the comet assay, followed by C. temensis (piscivorous). Nuclear abnormalities, such as binucleated, blebbed, lobed and notched cells, were used as evidence of cytotoxicity. Oreochromis niloticus followed by Hoplias malaricus, ominivorous/detritivotous and piscivorous species, respectively, presented the highest frequency of nuclear abnormalities, especially notched cells, while the herbivorous Astyanax bimaculatus lacustres showed the lowest frequency compared to the other species studied. Thus, for biomonitoring aquatic genotoxins under field conditions, the food web should also be considered.

Annual flooding and fish-mercury bioaccumulation in the environmentally impacted Rio Madeira (Amazon)

Regular annual flooding of the Amazonian rivers changes the aquatic environment affecting fish feeding strategies. The Rio Madeira has been greatly impacted by deforestation for agricultural projects, damming for a hydroelectric power plant, and alluvial gold extraction. We studied fish-Hg concentrations within defined weight ranges of representative species at the top of the food web, comparing high and low water seasons. Selected piscivorous species (Cichla spp, Hoplias malabaricus, Pinirampus pirinampu, Serrasalmus spp) showed a large variation of Hg concentrations but only "traíra" (Hoplias malabaricus) showed a statistically significant difference between seasons. However, the bioaccumulation trends during high and low waters were similar for "tucunaré" (Cichla spp) and "traíra" (Hoplias malabaricus) but different for "piranhas" (Serrasalmus spp), "barba chata" (Pinirampus pirinampu) and the detritivorous Prochilodus nigricans. Fish-Hg bioaccumulation is species specific; changes in feeding strategies brought by flooding seasons can change the bioaccumulation pattern without systematically affecting the overall accrual of methylmercury in tertiary consumer species. It appears that naturally occurring Hg and the high sediment load of the Rio Madeira are secondary factors in the Hg bioaccumulation pattern of fish species at the top of the food chain.

Anthropogenic impact of mercury accumulation in fish from the Rio Madeira and Rio Negro rivers (Amazonia)

Fish is an important concentrator of mono-methyl mercury and the main route to human contamination. We compared fish Hg bioaccumulation (within similar weight ranges) in two Amazonian river habitats during high-water seasons. The Rio Madeira has been greatly impacted by agriculture, alluvial gold extraction, and a hydroelectric reservoir, whereas the Rio Negro is much less affected by these human activities. The species at the top of the food web, Hoplias malabaricus (piscivorous; 80-668 ng Hg/g) and Cichla spp. (piscivorous; 42-747 ng Hg/g) showed the highest range of Hg concentrations. Nonpiscivorous species with comparable weight range, such as Potamorhina latior (detritivorous; 20-157 ng Hg/g) and Myleus torquatus (herbivorous; 2-182 ng Hg/g), had lower Hg concentrations. Triportheus elongatus (omnivorous; 5-350 ng Hg/g), with the lowest weight range, also showed a low range of Hg concentrations. Despite the Rio Madeira's higher sediment load as well as environmental impacts (deforestation, agriculture, hydroelectric reservoir, and alluvial gold mining) on natural Hg release, fish Hg bioaccumulation was no different between the two river habitats for nonpiscivorous species. In this small observational study only the species at the top of the food web (M. torquatus, Cichla spp, T. elongatus) showed higher mean Hg concentrations in the Rio Madeira than the dominantly wilderness habitat of the Rio Negro.

Fish consumption, mercury exposure and serum antinuclear antibody in Amazonians

Exposure to intrinsic Hg in fish was studied in Amazon populations with high prevalence of malaria disease. High fish-eater riverines were compared to urban (Manaus residents) low fish-eater riverines in regards to Hg exposure (hair-Hg) and serum antinuclear antibodies (ANA). Most riverines (99.0%) ate fish daily compared to only 3% of controls. Fish species high in MeHg was consumed more frequently (45.5%) by riverines than controls (18.8%). Mean hair-Hg (34.5 ppm) of riverines was significantly higher than controls (1.0 ppm). Although positive serum ANA was more frequently observed in riverine fish-eaters (12.4%) than controls (2.9%), there was no significant association between hair-Hg and ANA. High prevalence of malaria reporting among riverines was neither associated with Hg exposure nor with serum ANA. An autoimmune dysfunction is unlikely to occur as a result of MMHg exposure due to fish consumption.

Fish mercury bioaccumulation as a function of feeding behavior and hydrological cycles of the Rio Negro, Amazon

The acidic black waters of the Rio Negro are unimpacted by anthropogenic sources and yet, are characterized by fish containing relatively high Hg concentrations. Regular annual flooding alters the aquatic environment, thereby affecting fish feeding strategies. We studied the impact of annual flooding on fish-Hg bioaccumulation. Tucunarés (Cychla spp, carnivorous), Peixe-cachorro (Hydrolycus scomberoides, carnivorous), Traíra (Hoplias malabaricus, carnivorous), Piranha-branca (Serrasalmus aff. eigenamanni, carnivorous), Piranha-preta (Serrasalmus rhombeus, carnivorous), Acará (Acarichthys heckellii, omnivorous), Aracú (Leporinus friderici, omnivorous), Orana-preta (Hemiodus unimaculatus, omnivorous), Sardinha (Triportheus elongatus, omnivorous), Branquinha (Potamorhina latior, detritivorous), Jaraqui-escama-fina (Semaprochilodus taeniurus, detritivorous), and Pacú-branco (Myleus torquatus, herbivorous) were studied during high (July) and low waters (February) and categorized by body mass. Regardless of hydrological period, ranges of total-Hg concentrations were higher for carnivorous than for omnivorous, detritivorous and herbivorous species. Some species (Traíra, Sardinha, Peixe-cachorro, Piranha branca, Piranha preta) showed changes in feeding patterns as indicated by an inverse trend of Hg bioaccumulation with season. Species with similar trends of Hg bioaccumulation showed higher Hg concentrations during the flooded season (Aracú, Pacú branco and Orana preta) and some had lower Hg (Acará, Branquinha and Tucunarés). Fish Hg concentration is species specific and reflects changes in feeding-behavior dominance brought by annual inundation.

Fish consumption (hair mercury) and nutritional status of Amazonian Amer-Indian children

Fish are abundant and important dietary items for the Amer-Indians, and total hair-Hg (HHg) concentration is a reliable marker of fish consumption. We studied the impact of fish consumption (HHg) on the nutritional status of Indian children of Eastern Amazonia. Weight-for-height Z score (WHZ) was measured, and HHg was determined in 203 children younger than 10 years of age in three villages. There was significantly higher fish consumption in Kayabi children (16.55 microg Hg/g; SD, 11.44) than in children of the Munduruku villages of Missão-Cururu (4.76 microg Hg/g; SD, 2.09) and Kaburua (2.87 microg Hg/g; SD, 2.13). Anthropometric indices showed WHZ means of -0.27, -0.22, and 0.40, respectively, for Kayabi, Missão-Cururu and Kaburua villages. Despite a different pattern of fish-protein consumption between tribes, there was no significant correlation between WHZ and HHg concentrations (r2 = 0.0079; P < 0.2021). Dietary differences among Amazonian tribes can be traced and used in measuring health outcomes. Higher fish consumption, although important for Kayabis, was compensated by other protein sources by the Kaburua villagers.

Hair mercury (signature of fish consumption) and cardiovascular risk in Munduruku and Kayabi Indians of Amazonia

Fish is an important natural resource in the diet of inhabitants of the Amazon rain forest and a marker of its consumption (hair Hg) was used to compare selected cardiovascular risk parameters between tribes of Eastern Amazonia. Three Munduruku (Terra Preta, Kaburua, Cururu) villages and one Kayabi village at the banks of head rivers (Tapajos, Tropas, Kabitutu, Cururu, Curuzinho, Teles Pires) of the Tapajos Basin were studied in relation to fish Hg concentrations, mercury in hair (fish consumption) and erythrocytes, body mass index (height/weight, kg/cm2), and blood pressure. The mean fish Hg concentrations were higher in predatory (578.6 ng/g) than in nonpredatory species (52.8 ng/g). Overall only 26% of fish Hg concentrations were above 500 ng/g, and only 11% were above 1000 ng/g. There was no systematic trend in fish Hg concentrations from rivers with a history of gold-mining activities. The biomarker of fish consumption (hair Hg) was significantly associated with erythrocyte-Hg (r=0.5181; P=0.0001) and was significantly higher in Kayabi (12.7 microg/g) than in the Munduruku (3.4 microg/g). Biomarker-assessed fish consumption rate was higher in the Kayabi (110 g/day) than in the Munduruku villages (30 g/day). Although no significant differences in body mass index (BMI) were observed between tribes, there was a trend of lower increase in blood pressure with age among the higher fish consumers (Kayabi). Summary clinical evaluation did not detect neurologic complaints compatible with Hg intoxication (paraparesis, numbness, tremor, balancing failure), but endemic tropical diseases such as clinical history of malaria showed a high prevalence (55.4%). Fish is an abundant natural resource, important in the Indian diet, that has been historically consumed without perceived problems and can easily be traced through hair Hg. The exposure to freshwater fish monomethyl mercury is less of an issue than endemic infectious diseases such as malaria and lack of basic medical services.

Piranhas (Serrasalmus spp.) as markers of mercury bioaccumulation in Amazonian ecosystems

Mercury (Hg) concentration in fish depends on feeding strategies and age/size within the species as well as on water parameters related to acidity and Hg speciation. We chose two species of piranhas (Serrasalmus aff. eigenmanni and Serrasalmus rhombeus) to test their suitability as markers of Hg bioaccumulation. The results of Hg concentrations in piranhas of the Rio Negro, with no history of gold-mining activity, are similar to other Amazonian rivers with intensive gold mining. An increase in water Hg associated with low pH favored higher mean Hg concentrations in the two species. S. rhombeus in this habitat showed a consistently higher Hg concentration than S. eigenmanni. This result was attributed to fish size because of differences in correlation coefficient between S. rhombeus (r = 0.4443; P < 0.0001) and S. eigenmanni (r = 0.1520; P = 0.0135). Matching for fish weight resulted in comparable ranges of Hg concentrations between the two species.

Mercury in hair and in fish consumed by Riparian women of the Rio Negro, Amazon, Brazil

This work puts the risks and benefits of a mercury acquisition through a fish-dominated diet in the context of the other endemic health problems in the Amazon. Fish consumption rate was assessed after determining mercury concentrations in the most consumed fish and in hair of women at fertile age (15 to 45 years of age), living in remote localities of the Rio Negro basin (not impacted by gold mining). Fish-meals were consumed once a day (7.1%) but in most cases (78.6 %) at least twice a day with an estimated mean fish consumption rate of 170.5 g (range 23 to 293 g). The fish-species most preferred were Tucunarés (Cichla spp), Pacus (Mylossoma aureum and Myleus micans), Piranhas (Sarrasalmus spp), Cará (Satanoperca jurupari), Jaraquí (Semaprochilodus taeniurus). The mean Hg concentration in these species varies widely (38 to 592 ng g(- 1)) but 27% of samples had Hg concentrations above 500 ng g(- 1), and only 7% were above 1000 ng g(- 1). The hair-Hg concentrations ranged from 6.5 to 32.6 microg g(- 1) with 82% of them having concentrations above 10 microg g(- 1) (w.w.) hair. Hair-Hg concentrations were positively correlated with women's age (r=0.4500; P=0.0111). Clinical evaluation did not detected symptoms (paraparesis, tremor, numbness of limbs, sensory disturbances) compatible with Minamata disease, but there was a high (71%) incidence of clinical history of malaria. Fish is an abundant natural resource, rich in essential nutrients and important to the diet of 'ribeirinhos' of Brazilian Amazonia. We hypothesize that lack of basic medical care in these communities outweighs risk of naturally occurring fish-MMHg. Therefore food habits based on fish consumption is part of a successful strategy for survival and should be considered as a health asset.

Mercury biomagnification in a tropical black water, Rio Negro, Brazil

The population living along the riverbanks of the Amazon basin depends heavily on fish for nutritional support. Mono-methyl-mercury (MMHg) concentrates in fish, which can contaminate humans, the risk depending not only on fish MMHg concentration but also on the amount of fish consumed. We sampled nine locations of the Rio Negro basin, differing in water pH, Hg concentrations, and dissolved organic carbon (DOC), and determined total Hg from 951 fish samples of species representative of the food web: herbivorous, detritivorous, omnivorous, and piscivorous. Mercury concentrations varied widely in all species but showed a trend that depended on fish feeding strategies. The highest mean concentration was found in the piscivorous species (688.90 ng/g(-1)), followed by omnivorous (190.30 ng/g(-1)), detritivorous (136.04 ng/g(-1)), and herbivorous (70.39 ng/g(-1)). Fish Hg concentrations exceeding current safe limits (500 ng/g(-1)) for human consumption were found mainly in the piscivorous species (60%). Significant positive correlation between fish weight and Hg concentration was seen for the piscivorous Serrasalmus spp. (n = 326; r = 0.3977; p < 0.0001), Cichla spp. (n = 125; r = 0.4600; p < 0.0001), and Pimelodus spp. (n = 12; r = 0.8299; p = 0.0008), known locally as Piranha, Tucunaré, and Mandi, respectively. However, a negative correlation was seen for non-piscivorous Potamorhina latior (n = 30; r -0.3763; p = 0.0404) and Leporinus spp. (n = 44; r = -3987; p = 0.0073), known as Branquinha (detritivorous) and Aracu (omnivorous). Fish-Hg concentrations in the acidic waters (pH range, 4.09-6.31) of the Rio Negro habitat, with its wide gradient of Hg concentrations (3.4-11.9 microg/L(-1)) and DOC (1.85-15.3 mg/L(-1))--but no history of gold mining activity-are comparable to other Amazonian rivers. Opportunity fish catches in the Rio Negro habitat show high muscle-Hg derived from natural sources, but no systematic association with site-dependent geochemistry.

Characteristics of nasal T/NK-cell lymphoma among Brazilians

Nasal T/NK-cell lymphomas are highly associated with Epstein-Barr virus (EBV). They are more frequent in Asia than in Western countries. In Central and South America there are few studies about nasal T/NK-cell lymphoma and they have shown a strong predominance of this phenotype in Native American descents, supporting the hypothesis of a racial predisposition for the disease. We studied the lymphomas involving midline facial region at a Brazilian institution. T/NK cell lymphomas (16/25) were more frequently found compared to B lymphomas (9 cases, all B large cell). T/NK cell lymphomas involved predominantly the nasal region. Histologically they showed angioinvasion and necrosis. All of them were positive for CD3 and CD56 and showed numerous tumor cells labeled by EBER-1. Although disease was localized in 61% at diagnosis, there was no tendency to cure. The racial distribution of patients with T/NK-cell phenotype was similar to that found in B-cell lymphomas. EBV was more frequently found in adenoids than in palatine tonsils. In inflammatory lesions of the nasal and palatal regions EBV was not found. In the present study the relative frequency of T/NK versus B cell sinonasal lymphomas was high and similar to that observed in other Latin American countries. However, there was not any racial association with T/NK-cell phenotype and the tumor showed an agressive behavior similar to that reported in Asia. The high frequency of EBV-positive lymphocytes in nasopharyngeal lymphoid tissue (adenoids) suggests that they could serve as a reservoir for the virus.

Hair mercury speciation as a function of gender, age, and body mass index in inhabitants of the Negro River basin, Amazon, Brazil

Human mercury contamination can be monitored through hair analysis of mercury's inorganic and organic form as methylmercury (Me-Hg). Hair total mercury and Me-Hg were studied in a Negro River fish-eating population in relation to age, gender, and body mass index (BMI). This riverbank population eats fish at least twice a day and is exposed to high levels of Me-Hg. Total mercury ranged from 1.51 microg/g to 59.01 microg/g, with only 21% of the sampled population having Hg concentration of less than 10 microg/g hair. The mean percentage of Me-Hg was 71.3% (range 34% to 100%) of the total mercury in hair. No statistically significant differences were found in regard to age groups (children and adults) or BMI. However, women had significantly lower total mercury in hair than men, but the percentage of Me-Hg was not significantly different. Women in fertile age (15-40 years) had hair total mercury ranging from 1.65-32.63 microg/g, and 65% in this subgroup had hair mercury above 10 microg/g hair. The percentage of Me-Hg concentration in hair of this freshwater, fish-eating population is comparable to populations eating ocean fish from different parts of the world and does not seem to be affected by age, gender, and BMI.

Replication timing of homologous alpha-satellite DNA in Roberts syndrome

Roberts syndrome (RS) is associated with a characteristic constitutive heterochromatin anomaly, namely, at metaphase the centromeres and heterochromatic segments appear split. In addition to this cytogenetic phenomenon, known as the RS effect, several other cytological features, especially affecting mitotic chromosome disjunction, are also observed. Applying FISH to interphase nuclei, we investigated the replication patterns of homologous alphoid centromeric DNA of chromosomes 9, 11, 16 and 17 in three patients showing the RS effect and in four normal individuals. A tendency for homologous centromeres to replicate asynchronously was observed in RS patients. This tendency was more evident in chromosomes 9 and 16, with large heterochromatic blocks and particularly subject to RS effect. This asynchrony could reflect a more generalized alteration in repetitive DNA replication timing that, in turn, would prevent the establishment of proper cohesion between sister chromatid heterochromatin, leading to the RS effect.

Safety and efficacy of angioplasty with intracoronary stenting in patients with unstable coronary syndromes. Comparison with stable coronary syndromes

OBJECTIVE

To assess safety and efficacy of coronary angioplasty with stent implantation in unstable coronary syndromes.

METHODS

Retrospective analysis of in-hospital and late evolution of 74 patients with unstable coronary syndromes (unstable angina or infarction without elevation of the ST segment) undergoing coronary angioplasty with stent placement. These 74 patients were compared with 31 patients with stable coronary syndromes (stable angina or stable silent ischemia) undergoing the same procedure.

RESULTS

No death and no need for revascularization of the culprit artery occurred in the in-hospital phase. The incidences of acute non-Q-wave myocardial infarction were 1.4% and 3.2% (p = 0.6) in the unstable and stable coronary syndrome groups, respectively. In the late follow-up (11.2 +/- 7.5 months), the incidences of these events combined were 5.7% in the unstable coronary syndrome group and 6.9% (p = 0.8) in the stable coronary syndrome group. In the multivariate analysis, the only variable with a tendency to significance as an event predictor was diabetes mellitus (p = 0.07; OR = 5.2; 95% CI = 0.9-29.9).

CONCLUSION

The in-hospital and late evolutions of patients with unstable coronary syndrome undergoing angioplasty with intracoronary stent implantation are similar to those of the stable coronary syndrome group, suggesting that this procedure is safe and efficacious when performed in unstable coronary syndrome patients.

Selenium and mercury concentrations in some fish species of the Madeira River, Amazon Basin, Brazil

Samples of 7 species of piscivorous, omnivorous, and herbivorous fish caught at 12 different sites on the Madeira River, Amazon Basin, were analyzed for selenium and mercury. Selenium was determined by anodic stripping voltammetry and mercury by cold vapor atomic absorption spectrophotometry. The means for selenium concentrations ranged from 0.49 to 3.11 nmol/g and for mercury from 0.41 to 6.66 nmol/g depending on the fish species. The molar ratios of Hg:Se increased according to the fish trophic level. Piscivorous species had the highest mean ratio (4.0) and herbivorous species the lowest (0.9). There was a positive and statistically significant correlation between selenium and mercury concentrations for the herbivorous species (r = 0.716; p = 0.0088) not seen for omnivororus and piscivorous species (r = -0.2032; p = 0.3407). These findings are significant for the fish-eating population of the Madeira River because the ingestion of mercury would always be in excess of selenium.

Indices of mercury contamination during breast feeding in the Amazon Basin

Mercury pollution, due to gold mining has spread through the Amazon ecosystem reaching the food chain and affecting the indigenous people of the region. We studied the mercury contamination of 47 mothers and infants and the role of breast feeding in indices of mercury body burden in both groups, by measuring hair and milk Hg levels. Total mercury concentration of breast milk ranged from 0.0 to 24.8 (5.85, 5.2 S.D.) ng/g. Calculated levels of mercury exposure of breast fed babies indicated that 53% were above tolerable daily intakes (0.5 μg/kg body weight) recommended for adults by WHO. Mercury concentration in maternal hair was higher than in hair from breast-fed babies. Correlation analysis showed that mercury hair concentration in infants was significantly affected by maternal mercury contamination during pregnancy, but not during the post-natal breast-feeding period. The mercury concentration in milk was not significantly correlated with maternal or infant's hair Hg. A statistically significant correlation was found only between maternal and infant's hair mercury concentration (r=0.675; P=0.0001).

Concentration of mercury in hair of indigenous mothers and infants from the Amazon basin

Hair mercury concentration, as an indicator of mercury body load, was studied in 251 samples of indigenous women and children living in selected areas of the Amazonian region. The mothers or women of child-bearing age, either non-Indians or Indians, and their children were sampled along the Madeira River and in the Kayapó reservation (Fresco River), respectively. Among the sampled individuals there were mothers with infants less than 2 years old. Total mercury in hair was determined by cold vapor atomic absorption spectrometry after alkaline digestion. The distribution of hair mercury concentration greater than 10 microg/g occurred in 67.4% of non-Indian women and 25% of Indian women; overall only 1% of non-Indian women had concentrations of hair mercury above 50 microg/g. In women of child-bearing age, the median and range of hair mercury concentration was 14.08 microg/g, and 0.8-94.7 microg/g for non-Indians, and 8.30 microg/g, and 0.8-13.3 microg/g for Indians. The correlation between maternal hair mercury and mercury in hair of infants (less than 2 years of age) still breast-feeding, was statistically significant only for non-Indians (r = 0.555 p < 0. 001). The correlation between length of breast-feeding and mercury concentration in infant's hair was significant for Indian children (r = 0.512; p = 0.029) but not for non-Indian children (r = 0.025; p = 0.832). A subsampling of 30 mothers had segmented hair analysis that showed a mean decrease of 20% in body burden during pregnancy, thus indicating the extent of placental transference of mercury to fetuses.

RB1 deletion in gonadoblastoma in an XY female

Cytogenetic studies of normal and tumor cells in a patient with gonadal dysgenesis and bilateral gonadoblastoma were performed. The karyotype was 46,XY in peripheral blood lymphocytes and skin fibroblasts. The conserved region of the SRY gene was detected by polymerase chain reaction amplification. Sequencing of this region did not reveal any alterations. A 46,XY chromosome constitution was observed in the right gonadoblastoma, but a partial deletion of chromosome 13 was present in the left tumor. This deletion included band 13q14, where the retinoblastoma gene is mapped. The study of the polymorphism of the variable number of tandem repeats region in intron 17 of the RB1 locus disclosed loss of heterozygosity in both the left tumor, which showed the deletion of chromosome 13, and in the right tumor, where no chromosome alterations of chromosome 13 were detected. In situ hybridization covering 130 kb of RB1 showed that a partial deletion of one of the RB1 alleles had occurred in the right tumor. Since the deletions affected different alleles in each tumor, independent events must have been involved in the development of the tumors. These findings point toward a significant role of RB1 in the development of gonadoblastoma.

Dual role for the yeast THI4 gene in thiamine biosynthesis and DNA damage tolerance

The THI4 gene of Saccharomyces cerevisiae encodes an enzyme of the thiamine biosynthetic pathway. The plant homolog thi1, from Arabidopsis thaliana, is also involved in thiamine biosynthesis; but was originally cloned due to its capacity to complement DNA repair deficient phenotypes in Escherichia coli. Here, the behavior of a thi4 disrupted strain was examined for increased sensitivity to treatment with the DNA damaging agents ultraviolet radiation (UV, 254 nm) and methyl methanesulfonate (MMS). Although the thi4 null mutant showed a similar level of survival as the wild-type strain, a higher frequency of respiratory mutants was induced by the two treatments. A similar phenotype was seen with wild-type strains expressing an antisense THI4 construct. Further analysis of respiratory mutants revealed that these were due to mutations of mitochondrial DNA (mtDNA) rather than nuclear DNA, consisting of rho-petite mutants. Moreover, the frequency of mutations was unaffected by the presence or absence of thiamine in the growth medium, and the defect leading to induction of petites in the thi4 mutant was corrected by expression of the Arabidopsis thi1 gene. Thus, Thi4 and its plant homolog appear to be dual functional proteins with roles in thiamine biosynthesis and mitochondrial DNA damage tolerance.

Multivessel system for cold-vapor mercury generation. Determination of mercury in hair and fish

A multivessel system for the determination of mercury (Hg) by cold-vapor atomic absorption spectrometry (CV-AAS) and inductively coupled plasma atomic emission spectrometry (ICP-AES) was developed. The performance of the proposed device was tested by determining total Hg in quality-control samples of hair and fishes following acid digestion. Application of the apparatus to the determination of Hg by CV-AAS following alkaline digestion was studied as well. The detection limit obtained for CV-AAS was 0.11 ng/mL and for ICP-AES 1.39 ng/mL. The results show that the system is appropriate to be used in techniques involving cold-vapor generation of Hg.

FRAXF in a patient with chromosome 8 duplication

We report on a folate sensitive fragile site at Xq27-28 in a girl with a multiple congenital anomalies and mental retardation syndrome, who also carries a duplication of the long arm of chromosome 8. The fragile site was shown by FISH to be distal to both FRAXA and FRAXE. DNA hybridisation with probe OxF14 showed the amplification of the CGG repeats of locus FRAXF in the patient and in her clinically normal mother.

Erythrocyte protoporphyrin versus blood lead: relationship with iron status among children exposed to gross environmental pollution

The dose-response relationship between erythrocyte protoporphyrin (EP) and blood lead (PbB) was investigated among children with different subgroups of iron status. The data bank from Santo Amaro City, Brazil, was taken to study 490 children aged 1-9 years who lived at less than 900 m from a primary lead smelter. Mean PbB was 58.9 +/- 25.3 micrograms/dl and mean EP was 87.1 +/- 68.1 micrograms/dl. At PbB levels lower than 60 micrograms/dl, the dose-response curve for EP versus PbB followed the classical pattern; children with low iron status showing greater EP "response" than those with typical iron status and those with high iron status, after controlling for the effects of age and racial group. Among children with PbB > or = 60 micrograms/dl, EP response increased according to the following order: typical < low < high iron status.

Antimony oxidation states in antileishmanial drugs

Chemical methods specific for the determination of the levels of trivalent antimony (Sb+3) and pentavalent antimony (Sb+5) were used to investigate proprietary formulas used to treat leishmaniasis. Trivalent antimony was determined by differential pulse polarography, whereas Sb+5 was determined by iodine titration. Proprietary formulas based on N-meglumine antimoniate (Glucantime) were analyzed in detail. The results showed Sb+3 in all ampules of Glucantime. In formulations said to contain either 85 or 100 mg of Sb+5/ml, we found both forms of antimony. The amount of Sb+3 ranged from 10.5 to 15.8% (10.06-18.96 mg of Sb/ml). These findings raise issues on product stability and standardization and may help to clarify resistance to antimonial drugs and the reducing effect of tissue on Sb+5.