[Leptospirosis in French Guiana and the Guiana shield: Current knowledge in 2016]. / La leptospirose en Guyane française et sur le bouclier des Guyanes. État des connaissances en 2016.

Leptospirosis is a cosmopolitan zoonosis caused by bacteria of the genus Leptospira. Whether the distribution is worldwide, the hot and humid climate of the tropics is particularly conducive to its expansion. In most French overseas departments and territories, leptospirosis is considered as a public health problem. In French Guiana, a French department located in the northeastern part of the Amazon rainforest, it is supposed to be rare. The objective of this review was to make an inventory of the knowledge on human and animal leptospirosis in French Guiana and neighboring countries. A comprehensive search was conducted through the indexed and informal medical literature in English, French, Spanish and Portuguese. Thus, respectively ten and four publications were identified on human and animal leptospirosis in French Guiana, published between 1940 and 1995 in the form of case reports or case series. The publications concerning this disease in the other countries of the Guiana Shield, eastern Venezuela, Guyana, Suriname, and Brazilian state of Amapá, also scarce or nonexistent. However recent data from the French National Centre of leptospirosis showed a recent and sudden increase in the number of cases in the department, probably partly due to the development of diagnostic tools such as Elisa IgM serology. It is likely that leptospirosis is a neglected disease in the region, due to the lack of diagnostic tools readily available, the lack of knowledge of the local clinicians on this disease and the existence of many other pathogens with similar clinical presentation such as malaria, arboviruses and Q fever and Amazonian toxoplasmosis. The establishment of more large-scale studies on animal and human leptospirosis is necessary and urgent to know the true burden of this disease in our region.

Influence of breeding season on fecal glucocorticoid levels in captive Greater Rhea (Rhea americana).

Sex hormones and stress-related changes can be seasonally influenced. We investigate whether fecal glucocorticoid metabolite (FGM) levels can differ between male and female captive Greater Rheas during the breeding and non-breeding seasons. Over a 3-year-period, fresh fecal samples from 10 individuals (five of each sex) were collected during the breeding months (October, November, and December) and non-breeding months (April and June). A total of 960 samples were assayed using a commercial radioimmunoassay. Results showed that FGM levels (mean ± SE) were affected by the breeding season in a sex-dependent way. Male Greater Rheas showed significantly higher FGM levels in the breeding months than in the non-breeding months (13.44 ± 0.37 vs. 7.92 ± 0.1 ng/g feces, respectively). By contrast, females did not show FGM seasonal changes throughout the same sampling periods (7.55 ± 0.14 vs. 7.26 ± 0.73 ng/g feces). Moreover, during the breeding season months, males showed higher average FGM levels than females (13.44 ± 0.37 vs. 7.55 ± 0.14 ng/g feces, respectively), and no differences were found between sexes during the non-breeding season (7.92 ± 0.1 vs. 7.26 ± 0.73 ng/g feces, respectively). Our findings suggest that male Greater Rheas have a higher adrenocortical activity during the breeding season, which is probably indirectly related to the increased testosterone levels and agonist interactions that are also observed during that phase. Studies aimed to determine the appropriate sex ratio for captive rearing should be developed to minimize male agonist encounters and therefore improve welfare of the captive group.

Blood lead levels and enzymatic biomarkers of environmental lead exposure in children in Cordoba, Argentina, after the ban of leaded gasoline.

Lead (Pb) is a developmental neurotoxicant found in industrial activities, many of them already prohibited worldwide. This study aimed to evaluate current blood Pb (PbB) levels in children in Cordoba, Argentina, and to compare these with similar studies performed before Pb was banned in gasoline in 1996. We also sought to identify mechanistically relevant biomarkers by measuring δ-aminolevulinic acid dehydratase (δ-ALAD), superoxide dismutase (SOD), and catalase (CAT) activities. We finally aimed to determine whether sociodemographic characteristics are associated with Pb toxicity. Blood samples collected from 161 healthy children between September 2009 and February 2010 revealed mean PbB levels of 2.58 ± 0.30 µg/dl. Enzymatic δ-ALAD, CAT, and SOD activities showed no significant variations when plotted against PbB levels. Finally, children living in the suburbs have higher PbB levels than their city counterparts, while low socioeconomic status increased δ-ALAD inhibition compared with that of middle-income children. Overall, these results evidenced a substantial reduction in exposure to Pb in this pediatric population over a decade after Pb was restricted in gasoline and reveal the importance of pursuing novel biomarkers of toxicity along with the sociodemographic profile to complement Pb diagnosis.

Corticosterone stress response of Greater Rhea (Rhea americana) during short-term road transport.

The effect of transport stress on blood corticosterone levels in captive Greater Rheas was investigated. Twelve adult individuals (7 males; 5 females) were loaded in pairs inside wooden crates and transported along a paved road for 30 min. Blood samples were taken before the individuals were introduced into the crate (baseline value) and immediately after they were unloaded (30 min after capture). To assess whether corticosterone levels were affected by the blood sampling procedure per se, another 6 (nontransport) control birds (3 males; 3 females) were also captured and sampled at the same times as their transported counterparts. Plasma corticosterone concentrations were measured using a commercially available corticosterone (125)I radio-immunoassay kit. Baseline corticosterone levels were similar in the control and transported birds (9.0 ± 1.6 and 10.4 ± 0.8 ng/mL, respectively). Transportation induced a highly significant (P < 0.001), more than 40-fold increase in the corticosterone levels (433.6 ± 35.4 ng/mL) that was about 5 times higher (P < 0.001) than in their nontransported counterparts (88.4 ± 14.8 ng/mL). The present findings suggest that Greater Rhea is a species highly sensitive to stressful manipulations. Both blood sampling and transportation induced highly significant adrenocortical responses. Considering that transportation is one of the unavoidable common practices in the management of Greater Rheas and, as shown in the present study, that it induces a significant 40-fold corticosterone stress response, efforts should focus on helping to generate management transport standards for optimization of the welfare of this ratite.

Neuroendocrine changes and natriuresis in response to social stress in rats.

Sympathetic activation is detected by the tachycardic, hypertensive and hyperthermic responses during social conflicts in rodents and primates. Sympathetic nervous system activation promoting sodium retention has long been recognized to play a significant role in the development and maintenance of salt-sensitive hypertension. The objective was to investigate neuroendocrine activation and renal sodium excretion in response to chronic social stress. Male Wistar rats were subjected to social stress in accordance with the resident-intruder paradigm. Intruder rats were subjected to social confrontation once daily for 6 days. After the last confrontation, plasma corticosterone and urinary catecholamines were determined to assess the neuroendocrine activation. Plasma aldosterone, plasma and urinary creatinine, Na(+) , K(+) and urinary volume were also measured. Chronic social stress increased the urinary norepinephrine, dopamine and plasma corticosterone levels, with no changes in epinephrine levels. On the other hand, high plasma aldosterone levels and low urinary sodium excretion without differences in creatinine clearance were observed. In conclusion, social stress had a strong antinatriuretic effect, which is coincident with noradrenergic and corticoadrenal activation and an increase in plasma aldosterone levels. Activation of these factors may promote sodium retention, which has long been recognized to play a significant role in the development and maintenance of hypertension.

Beta-endorphin involvement in the regulatory response to body sodium overload.

The present study was performed to examine the role of the endogenous beta-endorphinergic system on blood pressure regulation, sympathetic and brain activity during body sodium overload. Beta-endorphin knockout (beta end-/-), heterozygous (beta end+/-) and wild-type (beta end+/+) mice were submitted for two weeks to either a normal- or a high-sodium diet (NSD and HSD, respectively), and systolic blood pressure (SBP), urinary catecholamines (as an index of sympathetic nervous system activity), and the brain pattern of Fos-like immunoreactivity (as a marker of neuronal activation) were evaluated in each group. HSD caused a significant increase in SBP in beta end-/- mutant mice compared with beta end+/+ mice kept in the same experimental conditions (P < 0.01), but no statistical differences were observed between beta end+/- and beta end+/+ on a HSD. Moreover, when animals from the three genetic lines were fed with a NSD no changes in SBP were evidenced. With regard to brain activity, beta end-/- mice maintained on a HSD showed a significant increase in Fos-like immunoreactive neurons in the median preoptic nucleus (P < 0.01) compared with beta end+/- and beta end+/+ animals. Additionally, beta end-/- mice had higher levels of urinary epinephrine excretion (P < 0.05) on a HSD in comparison to beta end+/+ and beta end+/- animals in the same experimental conditions. No differences, however, were registered in norepinephrine and dopamine urinary excretion in animals from the three genetic lines after two weeks on either a HSD or a NSD. In summary, our results indicate that the beta-endorphinergic system may play a part in the compensatory response to sodium overload, since the absence of beta-endorphin causes an increase in systolic blood pressure, and increases median preoptic nucleus neural activity and urinary epinephrine excretion.

Use of high-performance liquid chromatography with diode-array detection after a primary drug screening in patients admitted to the emergency department.

Two hundred fifty samples of patients admitted to the Emergency Department at the Hospital Municipal de Urgencias, Córdoba, Argentina for a drug screening by HPTLC, FPIA, spectrophotometric methods, and HPLC/DAD were randomly selected. The rate of positive screens was 34.0% with the following rate distribution: 12.0% alcohol, 13.6% nonsteroid antiinflammatory drugs (NSAIDs), 2.0% anticonvulsants, 0.8% barbiturates, 0.4% narcotics, 0.4% antidepressants, 2.8% cocaine, and 2.0% cannabinoids. Psychoactive drugs (alcohol, cocaine, and cannabinoids) were detected in 43.9% of the patients admitted for traffic accidents, namely 35.71% alcohol, 2.38% alcohol-cocaine, 2.38% alcohol-cannabinoids, 2.38% cocaine-cannabinoids, and 2.38% alcohol-cocaine-cannabinoids. These results help identify the trend of use and/or abuse of drugs and its relationship with different causes of admission (accidents, overdose, and other pathologies), age, and gender.

Abundance, use of space, and activity patterns of white-faced sakis (Pithecia pithecia) in French Guiana.

White-faced sakis (Pithecia pithecia) are among the least studied neotropical primates. The combination of shy and quiet behavior, their ability to move silently, and the extreme difficulty of capturing them may explain why very few field studies have been undertaken in undisturbed habitats. During the course of a wildlife rescue in French Guiana, six individuals were captured and translocated to a safe area of primary rainforest. In this area, based on the observation of 35 groups, the average group size was 2.3 animals (SD = 1.2) and a density of 0.28 group/km(2) (0.64 individuals/km(2)) was estimated from transect censuses. Our study focused successively on three radio-collared animals (two males and one female) over a 287-day period, starting from release to the loss of the animal. From the study start, the triangulation method was used prior to habitutation to human presence, followed thereafter by 1,327 hr of visual monitoring. The translocated animals settled down, and two of them had a stable and compact home range. Two of them merged in association with members of the resident population. A resident group had a much larger home range than previously reported: 148 and 287 ha, using grid cells and 100% minimum convex polygon techniques, respectively. A group composed of two translocated individuals (one male and one female) had a home range of 68 and 135 ha using the same techniques. Additionally, two solitary animals used 152 and 162 1-ha quadrats. We observed animals (translocated and residents) moving quickly in one direction up to 11.5 km. The mean daily path length of resident animals was 1,880 m. Sakis used the lower strata of the forest more when in group, and the intermediate strata more when solitary. Allogrooming is fairly common in social groups. On average, the activity period ranged from 7:17 to 15:59 hr.

[Blood lead levels in children of Cordoba City]. / Niveles de plomo en sangre en niños de la ciudad de Córdoba.

Exposure to environmental lead is a major hazard to public health. International Environmental Agencies have assessed that blood lead concentrations of 10.0-15.0 micrograms/dl or even lower may be a risk factor for children. This survey focussed on environmental lead contamination and tried to provide information about blood lead levels in the children population of Cordoba City. A total of 172 children between 6 months and 9 years of age assisted in health centers and hospitals from December 1995 to December 1996 were surveyed. Lead assessment was performed by atomic absorption spectrophotometry with graphite furnace. Results revealed that 73.3% of the children population studied exhibited blood lead levels lower than 10.0 micrograms/dl; 19.2% evidenced risk concentration levels (10.0-14.9 micrograms/dl) and 7.6% showed concentrations higher than 15.0 micrograms/dl. It was confirmed that children with elevated concentrations lived in areas where numerous car repair shops are located. Three of the subjects lived in slums. From the group with low blood lead levels (< 10.0 micrograms/dl), 25 children lived downtown or near main avenues of heavy traffic and belonged to middle class families. Our survey showed a high occurrence of children with lead levels higher than 15.0 micrograms/dl (7.6%) whose etiology risk factors have been identified. Prevention should be able to cut down this occurrence through a safe control of environmental lead sources.

Niveles de plomo en sangre en niños de la ciudad de Córdoba. / [Blood lead levels in children of Cordoba City]

Exposure to environmental lead is a major hazard to public health. International Environmental Agencies have assessed that blood lead concentrations of 10.0-15.0 micrograms/dl or even lower may be a risk factor for children. This survey focussed on environmental lead contamination and tried to provide information about blood lead levels in the children population of Cordoba City. A total of 172 children between 6 months and 9 years of age assisted in health centers and hospitals from December 1995 to December 1996 were surveyed. Lead assessment was performed by atomic absorption spectrophotometry with graphite furnace. Results revealed that 73.3

of the children population studied exhibited blood lead levels lower than 10.0 micrograms/dl; 19.2

evidenced risk concentration levels (10.0-14.9 micrograms/dl) and 7.6

showed concentrations higher than 15.0 micrograms/dl. It was confirmed that children with elevated concentrations lived in areas where numerous car repair shops are located. Three of the subjects lived in slums. From the group with low blood lead levels (< 10.0 micrograms/dl), 25 children lived downtown or near main avenues of heavy traffic and belonged to middle class families. Our survey showed a high occurrence of children with lead levels higher than 15.0 micrograms/dl (7.6

) whose etiology risk factors have been identified. Prevention should be able to cut down this occurrence through a safe control of environmental lead sources.

Sex hormones and lipoproteins in adolescent male offspring of parents with premature coronary heart disease and a control group.

OBJECTIVE: To compare pubertal maturation, sex steroid hormones, and lipoproteins and their interrelationships in male offspring of parents with premature coronary heart disease (cases) and a control group. DESIGN: This was a cross-sectional comparison of cases and members of a control group 10 to 15 years of age. SUBJECTS AND METHODS: Offspring were recruited from patient lists of area physicians. Members of the control group were recruited from area schools. Body mass (kg/m2), serum lipids, lipoproteins, apolipoproteins, estradiol, and free testosterone were measured. RESULTS: Differences in age were not significant, but offspring were taller, heavier, and more mature. Offspring had higher total and low density lipoprotein cholesterol. Offspring had lower estradiol levels in early puberty but higher levels in late puberty. With family history and body mass in the regression models for lipid parameters, free testosterone was a significant explanatory factor for total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein, and estradiol was a significant predictor for apolipoprotein B. The percent of the variance in the lipid parameters explained by testosterone and estradiol was small. CONCLUSION: Sex hormone concentrations appear to be modest but significant predictors of lipoprotein and apolipoprotein concentrations in offspring and a control group in cross-sectional analysis. After controlling for pubertal maturation, hormone and lipid concentrations differed in offspring and the control group.

An aflatoxin-associated mutational hotspot at codon 249 in the p53 tumor suppressor gene occurs in hepatocellular carcinomas from Mexico.

The p53 tumor suppressor gene is commonly mutated in human hepatocellular carcinoma (HCC). The most frequent mutation in HCC in populations exposed to a high dietary intake of aflatoxin B1 (AFB1) is an AGGarg-->AGTser missense mutation in codon 249 of the p53 gene. We analyzed HCCs from Monterrey, Mexico, for the codon 249ser hotspot mutation. We also analyzed the serum AFB1-albumin adduct levels of the donors and family members to measure the current AFB1 exposure in this population. Moreover, the presence of hepatitis B and/or C viral infection (HBV or HCV) was analyzed serologically in the patients. Tumor cells were microdissected from tissue sections and exon 7 p53 sequences were amplified by polymerase chain reaction from genomic DNA and sequenced directly. The serological tests for anti-p53 antibodies, HBV or HCV were done by ELISA. Immunohistochemical analysis of p53 protein was done using a polyclonal rabbit antiserum (CM-1). Eight of 21 cases were positive by p53 immunohistochemistry. Of the 16 cases sequenced for exon 7 of p53 three codon 249 AGGarg-->AGTser mutations were found. Serum antibodies recognizing p53 protein were found in one of 18 patients. Positive serology for HBV and/or HCV was found in 12 of 20 cases. The serum AFB1-albumin adduct levels in this population ranged from 0.54 to 4.64 pmol aflatoxin/mg albumin. These results indicate that dietary AFB1 and hepatitis viruses are etiological agents in the molecular pathogenesis of HCC in this geographic region of Mexico.

The Duffy blood group and resistance to Plasmodium vivax in Honduras.

To test the hypothesis that the Duffy blood group negative genotype is a factor in resistance to Plasmodium vivax, we determined the Duffy blood group, the malaria antibodies, and the slide-demonstrated infection rates with P. vivax and P. falciparum of 420 persons living in Nueva Armenia, Honduras. In all, 247 persons were Duffy negative. Demonstrated infections with P. falciparum were almost equally distributed between Duffy-positive (5,8%) and Duffy-negative (4.9%) persons. Similarly, Duffy-positive (25.6%) and Duffy-negative (28.2%) persons had equal proportions of indirect fluorescent antibody test titers suggestive of past or present P. falciparum infection. In contrast, all 14 P. vivax infections were found in Duffy-negative persons. There was no evidence suggesting that Duffy-positive and Duffy-negative persons had different exposures to malaria. The Duffy negative genotype FyFy appears to be a factor in resistance to P. vivax.