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This systematic review aimed to answer the research focused question: What are the effects of photobiomodulation (PBM) therapy on bone healing after ionizing irradiation in animal models? The EMBASE, LILACS, LIVIVO, PubMed, Scopus, and Web of Science databases, including gray literature, were searched using the following keywords: "Head and Neck Neoplasms"; "Ionizing Radiation"; "Low-Level Light Therapy"; and "Bone regeneration", focusing on the primary studies that assessed the effects of PBM therapy on animal models of irradiated bone. Six studies have met the eligibility criteria and presented an overall regular quality according to the risk of bias assessment tools. All the studies utilized rat animal model and near-infrared laser PBM at low power output setting. Most of the studies showed increased new bone formation, osteocytes, osteoblasts, and vascularization networking, as a result of PBM therapy. However, only one out of the six studies has not shown any differences in bone healing in both lased and non-lased animal groups. Nevertheless, PBM therapy is a potential tool to improve bone healing induced by ionizing radiation. However, due to the scarce number of studies and the great variability of laser parameters and treatment protocols, a clear conclusion cannot be drawn. Hence, extensive preclinical in vivo studies are warranted to ensure these beneficial effects have been addressed prior to translational clinical trials., (© 2022. The Author(s), under exclusive licence to Springer-Verlag London Ltd., part of Springer Nature.)

The common vampire bat (Desmodus rotundus) is a sanguivorous (i.e., blood-eating) bat species distributed in the Americas from northern Mexico southwards to central Chile and Argentina. Desmodus rotundus is one of only three mammal species known to feed exclusively on blood, mainly from domestic mammals, although large wildlife and occasionally humans can also serve as a food source. Blood feeding makes D. rotundus an effective transmissor of pathogens to its prey. Consequently, this species is a common target of culling efforts by various individuals and organizations. Nevertheless, little is known about the historical distribution of D. rotundus. Detailed occurrence data are critical for the accurate assessment of past and current distributions of D. rotundus as part of ecological, biogeographical, and epidemiological research. This article presents a dataset of D. rotundus historical occurrence reports, including >39,000 locality reports across the Americas to facilitate the development of spatiotemporal studies of the species. Data are available at https://doi.org/10.6084/m9.figshare.15025296 ., (© 2022. The Author(s).)

The COVID-19 pandemic has the potential to affect all individuals, however in a heterogeneous way. In this sense, identifying specificities of each location is essential to minimize the damage caused by the disease. Therefore, the aim of this research was to assess the vulnerability of 853 municipalities in the second most populous state in Brazil, Minas Gerais (MG), in order to direct public policies. An epidemiological study was carried out based on Multi-Criteria Decision Analysis (MCDA) using indicators with some relation to the process of illness and death caused by COVID-19. The indicators were selected by a literature search and categorized into: demographic, social, economic, health infrastructure, population at risk and epidemiological. The variables were collected in Brazilian government databases at the municipal level and evaluated according to MCDA, through the Program to Support Decision Making based on Indicators (PRADIN). Based on this approach, the study performed simulations by category of indicators and a general simulation that allowed to divide the municipalities into groups of 1-5, with 1 being the least vulnerable and 5 being the most vulnerable. The groupings of municipalities were exposed in their respective mesoregions of MG in a thematic map, using the software Tabwin 32. The results revealed that the mesoregion of Norte de Minas stands out with more than 40% of its municipalities belonging to group 5, according to economic, social and health infrastructure indicators. Similarly, the Jequitinhonha mesoregion exhibited almost 60% of the municipalities in this group for economic and health infrastructure indicators. For demographic and epidemiological criteria, the Metropolitana de Belo Horizonte was the most vulnerable mesoregion, with 42.9 and 26.7% of the municipalities in group 5, respectively. Considering the presence of a population at risk, Zona da Mata reported 42.3% of the municipalities in the most vulnerable group. In the joint analysis of data, the Jequitinhonha, Vale do Mucuri and Vale do Rio Doce mesoregions were the most vulnerable in the state of MG. Thus, through the outlined profile, the present study proved how socioeconomic diversity affects the vulnerability of the municipalities to face COVID-19 outbreak, highlighting the need for interventions directed to each reality., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Campos, Aratani, Cabral, Limongi and Oliveira.)

The COVID-19 pandemic brings to light the reality of the Brazilian health system. The underreporting of COVID-19 deaths in the state of Minas Gerais (MG), where the second largest population of the country is concentrated, reveals government unpreparedness, as there is a low capacity of testing in the population, which prevents the real understanding of the general panorama of SARS-CoV-2 dissemination. The goals of this research are to analyze the causes of deaths in different Brazilian government databases (Civil Registry Transparency Portal and InfoGripe) and to assess whether there are sub-records showing an unexpected increase in the frequency of deaths from causes clinically similar to COVID-19. A descriptive and quantitative analysis of the number of deaths by COVID-19 and similar causes was performed in different databases. Our results demonstrate that different official sources had a discrepancy of 109.45% between these data referring to the same period. There was also a 758.57% increase in SARI deaths in 2020, when compared to the average of previous years. Finally, it was shown that there was an increase in the rate of pneumonia and respiratory insufficiency (RI) by 6.34 and 6.25%, respectively. In conclusion, there is an underreporting of COVID-19 deaths in MG due to the unexplained excess of deaths caused by SARI, respiratory insufficiency, and pneumonia compared to previous years., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2020 Alves, Souza, Silva, Ramos and Oliveira.)

Spotted fever is the main rickettsial disease in Brazil. We report 12 cases of human parasitism by Amblyomma parkeri in the Atlantic rainforest, an area of Brazil to which spotted fever is endemic. Nine of the ticks were infected with Candidatus Rickettsia paranaensis.

Amblyomma ovale (Ixodida: Ixodidae) Koch, 1844 is widely-reported in the neotropical region and is the main vector in the epidemic cycle of Rickettsia parkeri strain Atlantic rainforest, a bioagent of a milder variety of spotted fever (SF). Because species with wide geographical distributions are known to exhibit variations that influence their vectorial capacity, the present study aimed to analyze genetic diversity and rickettsia infection of A. ovale collected during the investigation and surveillance of SF cases in the Cerrado and Atlantic rainforest (ARF) Brazilian biomes. Samples had their DNA extracted, amplified and sequenced for 16S rDNA, 12S rDNA, cytochrome oxidase subunit II and D-loop markers for tick analyses, as well as the gltA, htrA, ompA and ompB genes for rickettsia detection. Between 11 and 33 A. ovale haplotypes were identified, all of them exclusive to areas within individual analyzed biome areas. The A. ovale populations appeared to be structured, with Cluster I restricted to Cerrado + ARF isolated in Caatinga and Cluster II to ARF continuous area. Rickettsia bellii, R. parkeri strain Atlantic rainforest (first report for Goiás state, Cerrado), Rickettsia asemboensis (first record in A. ovale for Brazil) and Rickettsia felis (first detection in this ixodid) were identified. A. ovale clusters were not associated with rickettsia types., (© 2019 The Royal Entomological Society.)

The soft tick, Ornithodoros rietcorreai, is a parasite of the rodent, Kerodon rupestris, and, to a lesser extent, of bats living in rock cavities in Northeastern Brazil. This report describes the first recorded episodes of human parasitism by this argasid tick, reported to the Brazilian Ministry of Health in September 2017. We assessed outdoor environments, roofs, animal nests and chicken coops in five houses located in an urban area of Russas City, Ceará State, Brazil. Our results confirmed the presence of the tick in two of the assessed houses. The collected specimens were molecularly identified as O. rietcorreai. Of the ten individuals living in the investigated properties, three reported being parasitized by ticks. Although O. rietcorreai ticks were recovered from the evaluated houses, the primary hosts for the ticks were not identified. The retrospective medical records of parasitized individuals reported the following: local pruritus 3/3, malaise 3/3, local edema and erythema 3/3, local rash 3/3, local pain 3/3, slow lesion healing 3/3 and paresthesia 1/3. One of the individuals reported four parasitism episodes (March, June, July and August 2017) and required medical attention and the administration of anti-allergy and anti-inflammatory drugs. The aforementioned reports were the first to address human parasitism, with subsequent toxicosis, by this tick species in Brazilian urban areas. Attention was drawn to the potential consequences of such episodes to the health of previously exposed individuals., (Copyright © 2018 Elsevier GmbH. All rights reserved.)

In Brazil, active infections of Rickettsia spp. is confirmed in all regions, involving various species of ticks. During investigation of a new focus of Spotted Fever (SF) incidence in the state of Pernambuco, northeastern Brazil, tick species Rhipicephalus sanguineus sensu lato (Latreille), and Amblyomma pseudoconcolor were collected from one Canis familiaris and four Euphractus sexcinctus, respectively, and analized for the presence of rickettsial genes. Ten A. pseudoconcolor ticks (90.9%) were found to be infected with Rickettsia, whereas no evidence of Rickettsia spp. was found in R. sanguineus s. l. Genetic analysis based of five rickettsial genes showed that the detected strain is most closely related to Rickettsia amblyommatis (formerly Candidatus Rickettsia amblyommii). R. amblyommatis was, for the first time, detected in Amblyomma pseudoconcolor and the results pointed to this tick like a potential vector in the enzootic cycle of R. amblyommatis in a typical semiarid Brazilian savannah region. In conclusion, despite the need for further studies to confirm if R. amblyommatis was responsible for the observed case in the state of Pernambuco, the presence of this bacterium during an SF focussed investigation should be a major concern in terms of public health due the capacity of SF for rapid and extensive dispersion within Brazilian territory., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Amblyomma nodosum ticks were collected from one collared anteater ( Tamandua tetradactyla) in the Caatinga biome, Brazil. From one sample, we isolated a Rickettsia sp. that was phylogenetically close to Rickettsia sp. strain NOD, with 99.9, 100.0, and 99.8% identity for gltA, htrA, and ompA genes, respectively.

Although Espírito Santo state is considered an endemic area for Brazilian spotted fever (BSF) with related lethal cases, it also constitutes the only state of southeastern Brazil that currently lacks a specific confirmation of the specific rickettsial agent. In an attempt to a species level confirmation of the etiological agent of fatal rickettsiosis cases in Espírito Santo state, in this study we tested human sera obtained between 2015 to 2017 by means of qPCR and subsequent conventional PCR protocols targeting gltA (citrate synthase) and ompA (190-kDA outer membrane protein) rickettsial genes. All samples were found to contain rickettsial DNA through the citrate synthase qPCR protocol. By conventional PCR, rickettsial gltA and ompA specific DNA fragments were detected in 25% (one sample) and 50% (2 samples) of the screened sera, respectively. Obtained consensuses for each gene partial sequences were 100% identical to Rickettsia rickettsii gltA and ompA genes. The present study confirms for the first time R. rickettsii as the etiological agent of a lethal spotted fever group rickettsiosis in human patients from Espírito Santo state., (Copyright © 2018 Elsevier GmbH. All rights reserved.)

Amblyomma sculptum (Ixodida: Ixodidae) Berlese, 1888 is the most important tick vector in Brazil, transmitting the bioagent of the most severe form of spotted fever (SF) in part of the Cerrado (in the states of Minas Gerais and São Paulo). In another part of the Cerrado (Central-West region of Brazil), a milder form of SF has been recorded. However, neither the rickettsia nor the vector involved have been characterized. The aim of the current study was to analyse genetic variation and the presence of rickettsia in A. sculptum in Cerrado, from silent areas and with the milder form of SF. Samples were subjected to DNA extraction, amplification and sequencing of 12S rDNA, cytochrome oxidase subunit II and D-loop mitochondrial genes (for tick population analyses), and gltA, htrA, ompA and gene D (sca4) genes for rickettsia researches. Exclusive haplotypes with low frequencies, high haplotype diversity and low nucleotide diversity, star-shaped networks and significant results in neutrality tests indicate A. sculptum population expansions in some areas. Rickettsia amblyommatis, Candidatus Rickettsia andeanae and Rickettsia felis were detected. The A. sculptum diversity is not geographically, or biome delimited, pointing to a different potential in vector capacity, possibly associated with differing tick genetic profiles., (© 2017 The Royal Entomological Society.)

In Brazil, two pathogenic Rickettsia species have been identified causing tick-borne spotted fever (SF). The aetiological agent Rickettsia rickettsii causes serious illness, particularly in the south-eastern region of the country. Moreover, the Rickettsia sp. strain Atlantic Rainforest cause milder clinical manifestations in south-eastern, south and north-east regions. This study has sought to analyse predictive factors for fatal SF. A case-control study was performed using disease notification records in Brazil. The cases included were individuals with laboratory confirmation and fatal progression of SF, while the controls included individuals with SF who were cured. A total of 386 cases and 415 controls were identified (1 : 1.1), and the cases and controls were similar in age. The factors identified as being protective against death were reported presence of ticks (odds ratio [OR], 0.60; 95% confidence interval [CI], 0.41-0.88), residing in urban areas (OR, 0.47, 95% CI, 0.31-0.74) and presenting lymphadenopathy (OR, 0.43; 95% CI, 0.23-0.82). Males exhibited a greater chance of death (OR, 1.57; 95% CI, 1.13-2.18), as did patients who were hospitalized (OR, 10.82; 95% CI, 6.38-18.35) and who presented hypotension or shock (OR, 10.80; 95% CI, 7.33-15.93), seizures (OR, 11.24; 95% CI, 6.49-19.45) and coma (OR of 15.16; 95% CI, 8.51-27.02). The study demonstrates the severity profile of the SF cases, defined either as the frequency of hospitalization (even in cases that were cured) or as the increased frequency of the clinical complications typically found in critical patients. Opportune clinical diagnosis, a careful evaluation of the epidemiological aspects of the disease and adequate care for patients are determining factors for reducing SF fatality rates., (© 2017 Blackwell Verlag GmbH.)

In Brazil, Spotted Fever (SF) is caused by Rickettsia rickettsii and Rickettsia parkeri strain Atlantic Forest. In recent years, several human cases of a milder SF have been reported from the Maciço de Baturité region of Ceará State. Previous studies in this region found R. parkeri strain Atlantic Forest to be present in Rhipicephalus sanguineus sensu lato and Amblyomma ovale ticks. The present study isolated and identified the Rickettsia spp. present in this new endemic area in Brazil. In March 2015, R. sanguineus s.l. and A. ovale were collected in rural areas of the Maciço de Baturité region, and subjected to the isolation technique. A bacterium was isolated from one R. sanguineus s.l., which phylogenetic analysis clustered to the R. rickettsii group. In conclusion, R. rickettsii bacteria is circulating in the studied area and may in future have an impact on the clinical diagnoses and consequently cause changes in the profile of the disease in the region. In addition, we suggest the increase of epidemiological and environmental surveillance in the area, in order to prevent Brazilian Spotted Fever cases., (Copyright © 2017. Published by Elsevier B.V.)

The Rhipicephalus sanguineus (Latreille) complex (Acari:Ixodidae) is composed of species with intra- and interspecific morphological variation that make their diagnosis difficult. In the present study, male specimens of the R. sanguineus complex were collected from dogs in six districts of three regions of Brazil and submitted to molecular and scanning electron microscopy (SEM) analyses. Analysis of COX1 gene, 12S rDNA, and D-loop rDNA shows that ticks classified as R. sanguineus form two different clades. Morphological comparisons using SEM found adult males to exhibit morphological differences in Haller's organ, festoons, and adanal, spiracular, and genital plates, with the last having potential usefulness in distinguishing male specimens of the complex., (© The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.)

Rabies is one of the most important zoonosis in the world with high impact on public health. Studies report the presence of Lyssavirus in reservoirs of the wild cycle, highlighting the role of wild canines, marmosets, and vampire and non-vampire bats as potential vectors of the disease to domestic animals and human beings. Therefore, the reintroduction of rabies in urban environments from reservoirs of the wild cycle is a matter of concern. This study describes the profile of rabies cases documented in Brazil from 2002 to 2012, with emphasis on the wild transmission cycle of the disease. We carried out a descriptive study using records with information on the time of infection, persons with infection and location of confirmed cases of rabies in humans and animals, as well as data on anti-rabies treatments obtained from the Information System of Notifiable Diseases (Sinan) database. Within the study period, 82 cases of rabies transmitted by wild animals to humans were reported, predominantly in rural areas of the northern and north-eastern regions. Of the cases in humans, 72% did not receive post-exposure prophylaxis. Among wild mammals, vampire bats were the most frequent vectors of the disease. In the north-east region, 460 terrestrial wild mammals were reported with confirmed rabies. Over the study period, 1703 bats were reported to carry the rabies virus. In the south-east region, the most frequently reported carriers of the virus were non-vampire bats. The midwest and northern regions presented a lower number of records of rabies cases among terrestrial wild mammals. However, the high number of rabies cases among bovines reflects the role of the vampire bat as a maintainer of the rabies virus in the rural cycle. The present results are key to adjust the planning of rabies control in Brazil to the current epidemiological trends., (© 2015 Blackwell Verlag GmbH.)

The eco-epidemiological scenario of spotted fever (SF), a tick-borne disease that affects humans and other animals in several countries around the world, was analyzed in Rio de Janeiro (RJ) State, Brazil. During the last 34 years, 990 SF cases were reported in RJ (the Brazilian state with the highest population density), including 116 cases confirmed by serology (RIFI) or PCR, among 42.39% of the municipalities with reported cases of SF. The epidemiologic dynamics of SF in RJ State are very heterogeneous in time and space, with outbreaks, high mortality rates and periods of epidemiological silence (no SF cases reported). Furthermore, it exhibited a changing epidemiological profile from being rural to becoming an urban disease. This study identified arthropods infected with Rickettsia felis , R. bellii and R. rickettsii , and found that the abundance of ectoparasites was associated with specific hosts. The R. rickettsii -vector-host relationship was most evident in species-specific parasitism. This suggests that the association between dogs, cattle, horses, capybaras and their main ectoparasites, Rhipicephalus sanguineus and Ctenocephalides felis , Rhipicephalus microplus, Dermacentor nitens , and Amblyomma dubitatum , respectively, has a key role in the dynamics of R. rickettsii transmission in enzootic cycles and the maintenance of carrier ectoparasites, thus facilitating the existence of endemic areas with the ability to produce epidemic outbreaks of SF in RJ. This study found confirmed human infections for only the R. rickettsii carrier Amblyomma sculptum , which reinforces the importance of this species as a vector of the pathogen in Brazil. This study can be adapted to different eco-epidemiological scenarios of spotted fever throughout the Americas.

Background: Spotted fever is a tick-borne rickettsial disease. In Brazil, its notification to the Ministry of Health is compulsory. Since 2007, cases of spotted fever have been integrated to the Notifiable Diseases Information System, and epidemiological analyzes are part of the routines on surveillance programs., Methods: This descriptive study updates epidemiological information on cases of spotted fever registered in Brazil between 2007 and 2015., Results: In Brazil, 17,117 suspected cases of the disease were reported and 1,245 were confirmed in 12 states, mainly in São Paulo (550, 44.2 %) and Santa Catarina (276, 22.2 %). No geographic information was registered for 132 cases (10.6 %). Most of the infected people were men (70.9 %), mainly in rural areas (539, 43.3 %), who had contact with ticks (72.7 %). A higher number of suspected cases were registered between 2011 and 2015, but the number of confirmed cases and the incidence were relatively low. Moreover, 411 deaths were registered between 2007 and 2015, mainly in the southeastern region of the country, where the case-fatality rate was 55 %. Lack of proper filling of important fields of notification forms was also observed., Conclusions: The results showed expansion of suspected cases of spotted fever and high case-fatality rates, which could be related to diagnostic difficulties and lack of prompt treatment. These factors may comprise limitations to the epidemiological surveillance system in Brazil, hence improvement of notification and investigation are crucial to reduce morbidity and mortality due to spotted fever in Brazil.

Background: Hantavirus infection is an emerging zoonosis transmitted by wild rodents. In Brazil, high case-fatality rates among humans infected with hantavirus are of serious concern to public health authorities. Appropriate preventive measures partly depend on reliable knowledge about the geographical distribution of this disease., Methods: Incidence of hantavirus infections in Brazil (1993-2013) was analyzed. Epidemiological, socioeconomic, and demographic indicators were also used to classify cities' vulnerability to disease by means of multi-criteria decision analysis (MCDA)., Results: From 1993 to 2013, 1752 cases of hantavirus were registered in 16 Brazilian states. The highest incidence of hantavirus was observed in the states of Mato Grosso (0.57/100,000) and Santa Catarina (0.13/100,000). Based on MCDA analysis, municipalities in the southern, southeastern, and midwestern regions of Brazil can be classified as highly vulnerable. Most municipalities in northern and northeastern Brazil were classified as having low vulnerability to hantavirus cardiopulmonary syndrome., Conclusions: Although most human infections by hantavirus registered in Brazil occurred in the southern region of the country, a greater vulnerability to hantavirus was found in the Brazilian Midwest. This result reflects the need to strengthen surveillance where the disease has thus far gone unreported.

Objective: The aim of this study was to assess the effects of changes in plasma selenium on the outcome of critically ill children., Methods: Plasma selenium was prospectively measured in 99 children with acute systemic inflammation. The exposure variables were selenium level on admission and on day 5 of stay in the intensive care unit (ICU) and the difference in selenium concentrations between day 5 post-admission and the ICU admission (delta selenium). Selenium was given only as part of enteral diets. Age, malnutrition, red cell glutathione peroxidase-1 activity, serum C-reactive protein, Pediatric Index of Mortality 2, and Pediatric Logistic Organ Dysfunction scores were analyzed as covariates. The outcome variables were ventilator-free days, ICU-free days, and 28-d mortality., Results: Plasma selenium concentrations increased from admission (median 23.4 μg/L, interquartile range 12.0-30.8) to day 5 (median 25.1 μg/L, interquartile range 16.0-39.0; P = 0.018). After adjustment for confounding factors, a delta selenium increase of 10 μg/L was associated with reductions in ventilator days (1.3 d; 95% confidence interval [CI], 0.2-2.3; P = 0.017) and ICU days (1.4 d; 95% CI, 0.5-2.3; P < 0.01). Delta selenium >0 was associated with decreased 28-d mortality on a univariate model (odds ratio, 0.67; 95% CI, 0.46-0.97; P = 0.036). The mean daily selenium intake (6.82 μg; range 0-48.66 μg) was correlated with the increase in selenium concentrations on day 5., Conclusions: An increase in plasma selenium is independently associated with shorter times of ventilation and ICU stay in children with systemic inflammation. These findings raise the hypothesis that selenium supplementation could be beneficial in children with critical illnesses., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Despite the dramatic reduction in Trypanosoma cruzi vectorial transmission in Brazil, acute cases of Chagas disease (CD) continue to be recorded. The identification of areas with greater vulnerability to the occurrence of vector-borne CD is essential to prevention, control, and surveillance activities. In the current study, data on the occurrence of domiciliated triatomines in Brazil (non-Amazonian regions) between 2007 and 2011 were analyzed. Municipalities' vulnerability was assessed based on socioeconomic, demographic, entomological, and environmental indicators using multi-criteria decision analysis (MCDA). Overall, 2275 municipalities were positive for at least one of the six triatomine species analyzed (Panstrongylus megistus, Triatoma infestans, Triatoma brasiliensis, Triatoma pseudomaculata, Triatoma rubrovaria, and Triatoma sordida). The municipalities that were most vulnerable to vector-borne CD were mainly in the northeast region and exhibited a higher occurrence of domiciliated triatomines, lower socioeconomic levels, and more extensive anthropized areas. Most of the 39 new vector-borne CD cases confirmed between 2001 and 2012 in non-Amazonian regions occurred within the more vulnerable municipalities. Thus, MCDA can help to identify the states and municipalities that are most vulnerable to the transmission of T. cruzi by domiciliated triatomines, which is critical for directing adequate surveillance, prevention, and control activities. The methodological approach and results presented here can be used to enhance CD surveillance in Brazil., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Hantavirus cardiopulmonary syndrome is an emerging zoonosis in Brazil. Human infections occur via inhalation of aerosolized viral particles from excreta of infected wild rodents. Necromys lasiurus and Oligoryzomys nigripes appear to be the main reservoirs of hantavirus in the Atlantic Forest and Cerrado biomes. We estimated and compared ecological niches of the two rodent species, and analyzed environmental factors influencing their occurrence, to understand the geography of hantavirus transmission. N. lasiurus showed a wide potential distribution in Brazil, in the Cerrado, Caatinga, and Atlantic Forest biomes. Highest climate suitability for O. nigripes was observed along the Brazilian Atlantic coast. Maximum temperature in the warmest months and annual precipitation were the variables that most influence the distributions of N. lasiurus and O. nigripes, respectively. Models based on occurrences of infected rodents estimated a broader area of risk for hantavirus transmission in southeastern and southern Brazil, coinciding with the distribution of human cases of hantavirus cardiopulmonary syndrome. We found no demonstrable environmental differences among occurrence sites for the rodents and for human cases of hantavirus. However, areas of northern and northeastern Brazil are also apparently suitable for the two species, without broad coincidence with human cases. Modeling of niches and distributions of rodent reservoirs indicates potential for transmission of hantavirus across virtually all of Brazil outside the Amazon Basin.

The mutagenicity (clastogenicity) and the carcinogenicity (promoting potential) of cocaine were evaluated, respectively, by the mouse bone marrow micronucleus test (study I) and by the initiated rat liver bioassay (study II). In study I, two administration routes (i.p. and i.v.) and two sampling times (24 and 48 hours) after cocaine treatment were studied. Swiss male mice were treated with cocaine at doses of 0, 18, 37, and 75 mg/kg and 0, 2, 4, and 8 mg/kg by i.p. and i.v. routes, respectively. No significant differences were observed between treated and negative control groups regarding the frequencies of micronuclei and the polichromatic/normochromatic erythrocyte (PCE/NCE) ratios. In study II, the development of putative preneoplastic foci of hepatocytes expressing the enzyme glutathione S-transferase placental form (GST-P+) was utilized as the end-point marker in a 8-week rat liver bioassay. The animals were initiated for carcinogenesis by a single i.p. sub-carcinogenic dose of diethylnitrosamine (DEN). After a 6-week exposure to 5 or 10 mg/kg of cocaine i.v. twice a week there was no enhancement of GST-P+ foci development above the values of the control DEN-only treated animals. Also, cocaine did not induce any toxicity as evidenced by the absence of alterations of rat body and liver weights and of liver biochemical function and morphology. The results suggest that cocaine does not have a mutagenic effect on the mouse bone marrow cells or promoting activity on the rat hepatocarcinogenesis process.