Community-Based Ecotourism and Primate Watching as a Conservation Tool in the Amazon Rainforest

International Journal of Primatology - Community-based tourism is a participatory approach implemented to support the economic and social development of local communities. Here, we present the...     

The role of calcium channel blockers and resveratrol in the prevention of paraquat-induced parkinsonism in Drosophila melanogaster: a locomotor analysis

Studies have suggested that neuronal loss in Parkinson's disease (PD) could be related to the pacemaker activity of the substantia nigra pars compacta generated by L-type Ca(v) 1.3 calcium channels, which progressively substitute voltage-dependent sodium channels in this region during aging. Besides this mechanism, which leads to increases in intracellular calcium, other factors are also known to play a role in dopaminergic cell death due to overproduction of reactive oxygen species. Thus, dihydropyridines, a class of calcium channel blockers, and resveratrol, a polyphenol that presents antioxidant properties, may represent therapeutic alternatives for the prevention of PD. In the present study, we tested the effects of the dihydropyridines, isradipine, nifedipine, and nimodipine and of resveratrol upon locomotor behavior in Drosophila melanogaster. As previously described, paraquat induced parkinsonian-like motor deficits. Moreover, none of the drugs tested were able to prevent the motor deficits produced by paraquat. Additionally, isradipine, nifedipine, resveratrol, and ethanol (vehicle), when used in isolation, induced motor deficits in flies. This study is the first demonstration that dyhidropyridines and resveratrol are unable to reverse the locomotor impairments induced by paraquat in Drosophila melanogaster.     

The interaction between Trypanosoma rangeli and the nitrophorins in the salivary glands of the triatomine Rhodnius prolixus (Hemiptera; Reduviidae)

The parasite Trypanosoma rangeli develops in the intestinal tract of triatomines and, particularly in species of the genus Rhodnius, invades the hemolymph and salivary glands, where subsequent metacyclogenesis takes place. Many aspects of the interaction between T. rangeli and triatomines are still unclear, especially concerning the development of the parasite in the salivary glands and how the parasite interacts with the saliva. In this work, we describe new findings on the process of T. rangeli infection of the salivary glands and the impact of infection on the saliva composition. To ensure a complete infection (intestinal tract, hemolymph and salivary glands), 3rd instar Rhodnius prolixus nymphs were fed on blood containing T. rangeli epimastigotes using an artificial feeder. After molt to the 4th instar, the nymphs were inoculated with epimastigotes in the hemolymph. The results showed that the flagellates started to invade the salivary glands by the 7th day after the injection. The percentage of trypomastigotes inside the salivary glands continuously increased until the 25th day, at which time the trypomastigotes were more than 95% of the T. rangeli forms present. The salivary contents from T. rangeli-infected insects showed a pH that was significantly more acidic (<6.0) and had a lower total protein and hemeprotein contents compared with non-infected insects. However, the ratio of hemeprotein to total protein was similar in both control and infected insects. qPCR demonstrated that the expression levels of three housekeeping genes (18S rRNA, β-actin and α-tubulin) and nitrophorins 1–4 were not altered in the salivary glands after an infection with T. rangeli. In addition, the four major nitrophorins (NPs 1–4) were knocked down using RNAi and their suppression impacted T. rangeli survival in the salivary glands to the point that the parasite burden inside the R. prolixus salivary glands was reduced by more than 3-fold. These results indicated that these parasites most likely non-specifically incorporated the proteins that were present in R. prolixus saliva as nutrients, without impairing the biosynthesis of the antihemostatic molecules.     

Mutagenicity of diagnostic and therapeutical doses of radiopharmaceutical iodine-131 in Wistar rats

Iodine-131 (¹³¹I) is a radioisotope used for the diagnosis and treatment of thyroidal disorders such as hyperthyroidism and cancer. During its decay, ¹³¹I emits beta particles and gamma rays; its physical half-life is 8 days, and it is accumulated preferentially in the thyroid tissue. This study aimed to evaluate the cytotoxicity and mutagenicity of diagnostic and therapeutic doses of ¹³¹I using bone marrow cells of rats treated in vivo in a test system with a single dose by gavage. Concentrations of 5, 25, 50 and 250 μCi in 1 ml of water were used, and after 24 h, the animals were killed. Also, a concentration of 25 μCi/ml of water was used, and the animals were killed after 5 days. The results showed that no concentration of ¹³¹I was cytotoxic and that all concentrations were mutagenic. As a result, there was no statistically significant difference detected by the χ² test in the induction of chromosomal aberrations between the different doses. Thus, the present study demonstrated a significant increase in chromosomal aberration in bone marrow cells exposed to ¹³¹I regardless of the dose or the treatment time.     

How primary health care professionals and residents assess issues related to the oral health of older persons?

doi: 10.1111/j.1741‐2358.2009.00355.x
How primary health care professionals and residents assess issues related to the oral health of older persons? Background and objectives: It is known that older persons need integrated primary health care. However, oral health may not be a frequent concern of multi‐professional teams taking care of older persons. The aim of the present study was to evaluate knowledge and practices related to oral health care, as reported by professionals and residents in a primary health care service. Material and methods: One hundred and seventy‐three health professionals and residents were assessed in this cross‐sectional study by means of a structured questionnaire containing questions pertaining to oral health practices and beliefs. Participants were grouped based on their professions into “primary health care dentists” or “other primary health care professionals” and based on their working status into “permanent team” or “residents”. Results: Permanent team members (other professionals) assessed and recommended dental care more frequently than residents. Permanent team members (other professionals) also reported that they felt they were able to inform older patients in respect to oral health‐related issues more frequently than did residents (68.7% vs. 31.3%, respectively). Conclusion: Oral health‐related knowledge and beliefs were frequent among non‐dentists primary health care workers, suggesting that primary health care which integrates oral health represents an attainable goal.     

Trypanosoma evansi: concentration of 3-nitrotyrosine in the brain of infected rats

Nitric oxide (NO) is involved in many physiological processes, such as blood pressure control, neurotransmission, inhibition of platelet and neutrophil adherence, and the ability to kill tumor cells and parasites. The indirect determination of NO can be made by detection of 3-nitrotyrosine (3-NT) residues. The aim of this study was to measure the concentration of 3-NT in the brain of rats experimentally infected with Trypanosoma evansi. Twenty-four were inoculated intraperitoneally with cryopreserved blood containing 1 × 10⁶ trypomastigotes per animal. Twenty-four animals were used as negative controls and received 0.2 mL of saline by the same route. The experimental groups (group C and T) were established according to the time after infection and the degree of parasitemia as follows: four control subgroups (C3, C5, C10 and C20) with six non-inoculated animals each and four test subgroups (T3, T5, T10 and T20) with six animals infected with T. evansi in each group. The animals were anesthetized with isoflurane and subsequently euthanized at the days 3 (C3, T3), 5 (C5, T5), 10 (C10, T10) and 20 (C20, T20) post-infection (PI). The brain was removed and dissected into cerebellum, cerebral cortex, striatum and hippocampus. Concentration of 3-NT in the brain was determined by Slot blot technique. At the day 3 PI no changes were observed in the concentration of 3-NT among the groups. There was a significant reduction (p < 0.05) of 3-NT concentration in the striatum and cerebellum at the days 5 and 10 PI, respectively. At the day 20 PI a significant increase (p < 0.05) of 3-NT was observed in the cerebellum, cerebral cortex and hippocampus from the infected animals. Therefore, T. evansi infection caused changes in the concentrations of 3-NT in the central nervous system (CNS), which may be related to clinical signs and infection management.     

Tempo and mode of concerted evolution in the L1 repeat family of mice

A 300-bp DNA sequence has been determined for 30 (10 from each of three species of mice) random isolates of a subset of the long interspersed repeat family L1. From these data we conclude that members of the L1 family are evolving in concert at the DNA sequence level in Mus domesticus, Mus caroli, and Mus platythrix. The mechanism responsible for this phenomenon may be either duplicative transposition, gene conversion, or a combination of the two. The amount of intraspecies divergence averages 4.4%, although between species base substitutions accumulate at the rate of approximately 0.85%/Myr to a maximum divergence of 9.1% between M. platythrix and both M. domesticus and M. caroli. Parsimony analysis reveals that the M. platythrix L1 family has evolved into a distinct clade in the 10-12 Myr since M. platythrix last shared a common ancestor with M. domesticus and M. caroli. The parsimony tree also provides a means to derive the average half-life of L1 sequences in the genome. The rates of gain and loss of individual copies of L1 were estimated to be approximately equal, such that approximately one-half of them turn over every 3.3 Myr.      

Primate population dynamics: variation in abundance over space and time

The rapid disappearance of tropical forests, the potential impacts of climate change, and the increasing threats of bushmeat hunting to wildlife, makes it imperative that we understand wildlife population dynamics. With long-lived animals this requires extensive, long-term data, but such data is often lacking. Here we present longitudinal data documenting changes in primate abundance over 45 years at eight sites in Kibale National Park, Uganda. Complex patterns of change in primate abundance were dependent on site, sampling year, and species, but all species, except blue monkeys, colonized regenerating forest, indicating that park-wide populations are increasing. At two paired sites, we found that while the primate populations in the regenerating forests had increased from nothing to a substantial size, there was little evidence of a decline in the source populations in old-growth forest, with the possible exception of mangabeys at one of the paired sites. Censuses conducted in logged forest since 1970 demonstrated that for all species, except black-and-white colobus, the encounter rate was higher in the old-growth and lightly-logged forest than in heavily-logged forest. Black-and-white colobus generally showed the opposite trend and were most common in the heavily-logged forest in all but the first year of monitoring after logging, when they were most common in the lightly-logged forest. Overall, except for blue monkey populations which are declining, primate populations in Kibale National Park are growing; in fact the endangered red colobus populations have an annual growth rate of 3%. These finding present a positive conservation message and indicate that the Uganda Wildlife Authority is being effective in managing its biodiversity; however, with constant poaching pressure and changes such as the exponential growth of elephant populations that could cause forest degradation, continued monitoring and modification of conservation plans are needed.     

Extension of the geographic range of Ateles chamek (Primates,Atelidae): evidence of river-barrier crossing by an amazonian primate

The black-faced black spider monkey (Ateles chamek) is endangered because of hunting and habitat loss. There are many gaps in our understanding of its geographic distribution. The Ucayali–Solimões–Amazon fluvial complex is currently recognized as the northern boundary of the species’ range, although published reports have indicated that it occurs north of the Rio Solimões. In this study we investigate published records, generate new field records, and assess the current information concerning the northern boundary of this species’ range. We conducted the study at the Mamirauá Sustainable Development Reserve in the central Brazilian Amazon, an area of 1,124,000 ha that consists entirely of Amazonian flooded forest (várzea). We collected data on the occurrence of the species from museum specimens and through field surveys, including interviews with local residents, direct observations, and the collection of new museum specimens. We confirmed the presence of A. chamek at 17 locations in the reserve, one of which was an island formed by a river bend cut-off that would have effectively taken any resident spider to the (new) north bank of the Solimões. We therefore conclude that fluvial dynamics were involved in creating the conditions for the dispersal and colonization of the species on the northern bank of the Rio Solimões. The data we present extends the known distribution of the species and increases its representation in protected areas.