Northeastern Region Of Brazil Research Articles

Assessment of Biochemical, Inflammatory Biomarkers and Ultra-Processed Food Consumption in Children with Small Intestinal Bacterial Overgrowth: A Cross-Sectional Study

Objective: This study evaluated anthropometric, biochemical, and inflammatory biomarkers, as well as dietary intake in Brazilian children diagnosed with small intestinal bacterial overgrowth (SIBO) and compared them with their counterparts without SIBO. Methods: This was a cross-sectional study with 106 children aged 7 to 10 years. A glucose-hydrogen breath test was performed to diagnose small intestinal bacterial overgrowth (SIBO). Anthropometric and dietary characteristics were assessed. Blood samples were collected and serum biochemical parameters and cytokines were measured. Results: The occurrence of SIBO was 13.2%. Age, BMI, BMI/age WC, BFP, sex and biochemical markers were similar between SIBO-positive and SIBO-negative children (p > 0.05). High consumption of ultra-processed foods tended to be higher in SIBO-positive compared to SIBO-negative children (47.8 ± 8.2 vs. 42.6 ± 9.5, p = 0.06). Serum levels of IL-17 were higher in SIBO-positive than in SIBO-negative children [69.5 (5.4–125.7) vs. 53.4 (2.3–157.7), p = 0.03], while serum levels of IL-10 were lower in SIBO-positive than in SIBO-negative children [2.3 (0.6–7.2) vs. 5.7 (0.5–30.8), p = 0.04]. Finally, in a logistic regression adjusted for sex, BMI and age, consumption of ultra-processed foods (p = 0.03) and IL-6 levels (p = 0.003) were found to contribute to the occurrence of SIBO. Conclusion: this study identified for the first time an occurrence of 13% of SIBO in children living in the northeastern region of Brazil and showed that consumption of ultra-processed foods and serum levels of IL-6 may influence the occurrence of the SIBO in the pediatrics population.

New records of Cassidinae and Cerambycidae (Coleoptera: Chrysomeloidea) from Baturité Massif, Brazil, with the description of a new species of Charidotis (Coleoptera: Chrysomelidae: Cassidinae)

The Baturité massif, situated in Ceará state’s central hinterland, is one of the largest humid mountain ranges in the Brazilian semi-arid region. Flora and vertebrate surveys have been conducted in the region, revealing endemic species, as well as a combination of fauna and flora from neighboring biomes, the Atlantic and Amazon rainforests. However, invertebrate inventories have been scarce, leaving a significant portion of the region’s biodiversity unexplored. This paper presents the outcomes of collaborative expeditions conducted by the recently established Museu de História Natural do Ceará Prof. Dias da Rocha and Museu Nacional/Universidade do Rio de Janeiro to fill this knowledge gap by promoting surveys to document the region’s biodiversity. As a result, one new species of tortoise beetle is described from the massif, Charidotis rochai Simões and Sekerka, new species. Additionally, we report thirteen new state records for the beetle subfamilies Cassidinae (Chysomelidae), and Cerambycinae and Lamiinae (Cerambycidae). Among these records, eight genera are documented for the first time in the state of Ceará, and the species Centrocerum variatum (Newman, 1841) constitutes the first record in the northeastern region of Brazil. These findings underscore the significance of survey initiatives and the need for comprehensive biodiversity study within the Baturité massif.

The longest multiannual drought in Northeastern Brazil

The Northeastern region of Brazil has long history of drought with impacts on water supply for cities and agriculture. However, the last drought that occurred in the region had unprecedented magnitude and periodicity, making it the longest multiannual drought in Northeastern Brazil. Thus, understanding and characterizing the behavior of this phenomenon is necessary, considering that another episodes may occur. Thus, the objective of this study was to characterize the drought trend in the Northeastern region of Brazil, with the application of the Palmer Drought Severity Index (PDSI). The application of PDSI was carried out with the monthly calculation of the water balance coefficients referring to the soil water balance between the years 2000 and 2019, depending on the relative soil moisture values. The results obtained were submitted to the Mann-Kendall test to identify monthly trends in the index. The annual drought variability in Northeastern Brazil showed moderate to extreme intensity, with the worst drought being observed between the years 2012 and 2019. The monthly drought average shows the Mid-Northern and “Sertão” regions as the most critical, with monthly trend of significant drought severity. The positive trend was observed in the Eastern, Southern and Western coast regions of NEB.

Urban Heat Island Assessment in the Northeastern State Capitals in Brazil Using Sentinel-3 SLSTR Satellite Data

The lack of a solid methodology defining urban and non-urban areas has hindered accurately estimating the Surface Urban Heat Island (SUHI). This study addresses this issue by using the official national urban areas limit together with a surrounding areas classification to define three different reference classes: the urban adjacent (Ua), the future urban adjacent (FUa), and the peri-urban (PUa), consequently providing a more accurate SUHI estimation on the nine northeastern Brazilian capitals. The land surface temperature was obtained in this study using the Sentinel-3 satellite data for 2019 and 2020. Subsequently, the maximum and average SUHI and the complementary indexes, specifically the Urban Thermal Field Variation Index (UTFVI) and the Thermal Discomfort Index (TDI), were calculated. The UTFVI expresses how harmful the eco-environmental spaces are, with a very strong SUHI for three capitals. In addition, the TDI, with values between 24.6–28.8 °C, expresses the population’s thermal comfort, with six capitals showing a very hot TDI. These findings highlight the need for strategies to mitigate the effects of the SUHI and ensure the population’s thermal comfort. Therefore, this study provides a better SUHI understanding and comparison for the Brazilian northeastern region, which has diverse areas, populations, and demographic variations.

Canine visceral leishmaniasis: Seroprevalence and georeferencing in the state of Santa Catarina, Brazil

Canine visceral leishmaniasis (CVL) has long been considered an endemic disease in the northern and northeastern regions of Brazil, while the southern region remains non-endemic. However, in recent years, several cases of CVL have been reported in southern states. The objective of this work was to determine the seroprevalence of CVL in dogs in the state of Santa Catarina, Brazil, through immunochromatographic tests (DPP®) and ELISA (Enzyme-Linked Immunosorbent Assay) and its correlation with environmental characteristics through georeferencing. Blood samples from dogs (n = 1227) were collected in six mesoregions of the state and evaluated by the rapid test (DPP®). Positive samples were sent to Lacen (Central Public Health Laboratory) in Santa Catarina to be tested using ELISA. Information obtained from the epidemiological questionnaire was subjected to statistical analysis (Chi-square and Student's t-test; P < 0.05) to verify the correlation between serology and the analyzed variables. The locations (GPS) of the samples were used for georeferencing and creating heatmaps (Kernel Method). Four animals that died from CVL were necropsied and organ samples were collected for molecular analysis (PCR), immunohistochemistry, and histopathology (HE). Of the 1227 dogs analyzed, 22 (1.8%) were reactive in the DPP® and of these, 7 (0.6%) were also positive in the ELISA. A correlation (P < 0.01) was observed between positive serology and region, environment, access to the street, and clinical signs. The positive cases were concentrated in the eastern region of the state, in low-altitude areas with average rainfall and higher average temperatures, and in more populated areas close to forest fragments. PCR, HE, and immunohistochemistry, along with serology, have proven to be efficient for characterizing positive cases.

Drastic reduction in the notification of acute cases of Chagas disease in the Northeast region of Brazil. Epidemiological evaluation in the period 2001–2021

Chagas disease (CD), caused by the protozoan Trypanosoma cruzi (T. cruzi), is a neglected disease endemic to some Latin American countries, including Brazil. Soon after infection, individuals develop an acute phase, which in most cases is asymptomatic and may go undetected. However, when CD is detected early, notification in the Notifiable Diseases Information System (SINAN), is mandatory. This study aimed to evaluate the information registered in the SINAN database and to determine the epidemiological profile of acute CD in Northeast Brazil, an endemic region, from 2001 to 2021. According to this survey, 1,444 cases of acute CD were reported in the Northeastern region of Brazil during this period. During the first six years, referred to as period 1, 90.24% of the notifications were registered, while the number of notifications significantly decreased in the subsequent years, referred to as period 2. Most individuals diagnosed with acute CD were Afro-Brazilian adults. All known routes of infection by the parasite were reported. Vector-borne transmission was predominant during period 1 (73.29%) and oral transmission during period 2 (58.87%). All nine states in Northeast Brazil reported cases in both periods. A higher incidence of disease was reported in Rio Grande do Norte (RN) during period 1, and in Maranhão (MA) during period 2. Our results show that CD remains a significant public health challenge.

Effects of the latest drought on the alluvial aquifer of a semiarid region in northeastern Brazil

Effects of the latest drought on the alluvial aquifer of a semiarid region in northeastern Brazil

Predictive Potential of Maize Yield in the Mesoregions of Northeast Brazil

Most of the northeastern region of Brazil (NEB) has a maize production system based on family farming, with no technological advances and totally dependent on the natural rainfall regime, which is concentrated in 4 to 5 months in most parts of the region. This means that the productivity of this crop is low in the NEB. In the northern mesoregions of the NEB, rainfall is concentrated between January and June, in the east of the NEB from April to September, and in the west of the NEB from October to March. The growing season takes place during these semesters. With this in mind, our objective was to develop a model based on canonical correlation analysis (CCA) to predict corn production in the mesoregions of the NEB between 1981 and 2010, using accumulated precipitation per semester as the predictor variable and predicting the observed production in kg/ha. Our results showed that the CCA model presented higher correlations between observed and simulated production than that obtained simply from the direct relationship between accumulated rainfall and production. The other two metrics used, RMSE and NRMSE, showed that, on average, in most mesoregions, the simulation error was around 200 kg/ha, but the accuracy was predominantly moderate, around 29% in most mesoregions, with values below 20% in six mesoregions, indicative of better model accuracy, and above 50% in two mesoregions, indicative of low accuracy. In addition, we investigated how the different combinations between two modes of climate variability with a direct influence on precipitation in the NEB impacted production in these 30 years, with the combination of El Niño and a positive Atlantic dipole being the most damaging to harvests, while years when La Niña and a negative Atlantic dipole acted together were the most favorable. Despite the satisfactory results and the practical applicability of the model developed, it should be noted that the use of only one predictor, rainfall, is a limiting factor for better model simulations since other meteorological variables and non-climatic factors have a significant impact on crops. However, the simplicity of the model and the promising results could help agricultural managers make decisions in all the states that make up the NEB.

Filarial Nematodes in Dogs from the Northeast Region of Brazil.

Medical and veterinary filarial nematodes are transmitted by blood-feeding vectors. In dogs, these parasites are mainly represented by nematodes in which microfilariae dwell in the blood (Dirofilaria spp. and Acanthocheilonema spp.) or skin (Cercopithifilaria spp. and Onchocerca lupi). The aim of this study was to determine the prevalence of these filarial infections in dogs residing in a touristic, heavily populated location in the northeastern region of Brazil. Blood samples (n = 245) were assessed by a modified Knott test, followed by a qualitative ELISA test (SNAP® 4Dx® Plus, IDEXX Laboratory, Westbrook, Maine, USA) for the detection of antibodies against Anaplasma spp., Borrelia burgdorferi sensu lato, Ehrlichia spp. and antigens of Dirofilaria immitis. Skin samples (n = 71) were microscopically examined and molecularly assessed through a PCR targeting the 12S rRNA gene. Microfilariae and antigen of D. immitis were detected simultaneously in 15 (6.1%; 95% CI = 3.7-9.8) animals. Nine animals (3.6%; 95% CI = 1.9-6.8) were D. immitis antigen positive but microfilariae negative and nine other animals (3.6%; 95% CI = 1.9-6.8) were microfilariae positive but D. immitis antigen negative. D. immitis positive dogs were found in four different municipalities. No filarioids were detected in the skin after microscopical and molecular analyses. Data from this study demonstrate that D. immitis is the main filarial nematode infecting dogs in coastal areas in northeastern Brazil. Based on the potential risk of infection in which animals are submitted, it is essential to perform tests to detect microfilariae and D. immitis antigen. Preventive measures must be adopted by using microfilaricidal compounds and anti-feeding insecticides to prevent canine infection.

Impact of feeding native Caatinga pasture on the rumen histomorphometry of sheep raised in semi-extensive management.

In the northeastern region of Brazil, sheep and goat farming, encompassing around 20 million animals, is predominantly a subsistence activity. Forage quality plays a crucial role in animal productivity, posing a complex interplay between plant and animal aspects. The Caatinga biome, vital for livestock in the region, serves as a significant source for animal diet through pastures. This study aimed to conduct a histomorphometric evaluation of sheep rumens in a semi-extensive system, comparing those feeding on native Caatinga pastures to those on cultivated pastures. Histological processing followed standard protocols, with morphometry focusing on six viable rumen papillae and the submucosa and muscular layer thickness. Statistical correlation analysis revealed morphological differences in papillae across various rumen regions. Morphometric data indicated no significant difference in papillae area between the groups, with average values in Group A surpassing those in Group B, except for width. This study establishes a morphological and morphometric pattern for rumen regions linked to diet types-native or cultivated. The findings not only enhance understanding of the dietary foundation in the Caatinga's extensive system, but also contribute valuable insights for formulating nutritional strategies to enhance sheep production in the region. This research sheds light on the intricacies of forage-based animal nutrition, particularly in semi-extensive systems, offering a foundation for future studies and practices to optimise livestock management in the northeastern Brazilian context.

Implementation of a pulmonary rehabilitation program for patients with long COVID in Northeastern region of Brazil: a feasibility study

Objective: to implement and evaluate the feasibility of a pulmonary rehabilitation (PR) program for patients with long covid in the northeast region of Brazil. Methods: patients participated in a 12-week (2 sessions per week, 60 minutes per day) outpatient comprehensive PR programme. Socio-demographics and clinical variables were recorded during the baseline assessment. The feasibility was assessed through adherence analysis to the PR program. Exercise capacity, functional capacity, functional status, depressive symptoms severity and dyspnoea were assessed at baseline and after completion of study protocol. Results: the per-protocol study population consisted of 28 patients (64.2% female), mean age 55.3 ± 17.3 years, and the main complaint was limitation of efforts (67.8%). The feasibility of the PR program was 82.1% (n=23). Following PR, significantly improvements were found for the following parameters: exercise capacity (p&lt;0.001), functional capacity (p&lt;0.001), functional status (p=0.01), depressive symptoms severity (p=0.001) and dyspnea (p=0.01). Conclusion: PR is a feasible and effective intervention for improving physical and psychosocial outcomes of patients with long covid.&#x0D;

P1108 Factors Associated with Delayed Diagnosis of Inflammatory Bowel Disease and Risk of Complications: Analysis of the Brazilian National Registry

Abstract Background The Brazilian Organization for Crohn's Disease and Colitis (GEDIIB) has established a national registry of inflammatory bowel disease (IBD). Timely diagnosis and treatment of the disease are crucial to mitigate the risk of complications in this patient population. Therefore, this study aimed to assess the variables associated with delayed diagnosis and the frequency of complications in IBD patients in Brazil. Methods A cohort study was conducted from August 2020 to August 2023. Data were obtained from medical records and patient consultations using the REDCap platform, with approvals from the ethics boards of participating institutions. Patients were categorized based on the time from symptom onset to diagnosis: &amp;lt; 1 year, 1 to 1 year 11 months, and ≥ 2 years. Socioeconomic and clinical data, such as disease extension, use of biological therapy, and complications like the need for surgery or hospitalization, were evaluated. Results The study included 2,436 patients, with 1,147 diagnosed with ulcerative colitis (UC) and 1,289 with Crohn's disease (CD). Of these, 62% were managed in public centers, and 38% in the private system. The age at diagnosis was 38 ± 15.5 years for UC and 33.7 ± 14.9 years for CD, with females predominating (64.5% for UC and 53.4% for CD). Among UC patients, disease extension included pancolitis (43.5%), left colitis (28.8%), and proctitis (27.7%). The time between symptom onset and diagnosis was longer in CD patients (p&amp;lt;0.001), as follows: &amp;lt; 1 year (UC 58.4% and CD 50.9%), 1 to 1 year 11 months (UC 22.3% and CD 21.1%), and ≥ 2 years (UC 19.3% and CD 28%). The shortest interval in UC patients was observed in private services (p&amp;lt;0.001), Southern and Northeastern regions of Brazil (p&amp;lt;0.001), and in patients without extraintestinal manifestations (EIM) (p=0.003). No differences were noted regarding disease extent, need for surgery, hospitalization, presence of cancer, or use of biological therapy. In CD patients, the shortest interval was observed in private services (p&amp;lt;0.001), the Southern region of Brazil (p&amp;lt;0.001), and was associated with a lower rate of hospitalization due to complications or disease activity (p=0.032). Among those who underwent surgery (35.6%), patients operated on in a public university hospital experienced a greater delay in diagnosis (p=0.014). No differences were observed regarding the presence of perianal disease, need for surgery, cancer, or use of biological therapy. Conclusion The window of opportunity is imperative to reduce complications, especially in CD. Further epidemiological studies are needed to shape national public health policies, emphasizing early diagnosis and appropriate treatment of IBD.

Epidemiological approach to Cryptococcus meningitis and related species in northeast Brazil: a scoping review

Introduction: Cryptococcosis is a fungal infection associated with yeast of the Cryptococcus genus. It is an opportunistic infection, more prevalent in individuals with AIDS, primarily manifesting as meningitis. Although there are numerous cases of cryptococcosis in northeastern Brazil, little is reported in the literature regarding meningitis cases. Objective: This study aimed to conduct a scoping review of meningitis cases associated with the Cryptococcus genus reported in the northeastern region of Brazil. Methodology: Four databases were utilized. Twenty-one studies were selected, totaling 492 cases. All states had publications on cryptococcal meningitis cases. RESULTS: The results revealed few studies on Cryptococcus meningitis in the region, with 492 identified cases. The majority were caused by Cryptococcus neoformans (356 cases), followed by C. gattii (98 cases), and other related species. AIDS was the primary underlying condition, associated with high mortality. Genetic research was underutilized. Conclusion: There is a need to enhance diagnostic methods in conjunction with increased case reporting to obtain a more detailed and comprehensive understanding of the epidemiology of neurocryptococcosis in northeastern Brazil.

Exploring critical incidents technique on social justice themes with Brazilian physical education teacher-researchers

This research is qualitatively oriented and aims to analyze themes of social justice—according to the methodology proposed by the international project EduHealth—based on critical incidents in physical education classes. The incidents have been identified by six physical education teacher-researchers who produced vignettes from the situations. Three of them are Master’s students from the Postgraduate Program in Physical Education at the Federal University of Rio Grande do Norte (PPGEF-UFRN) and three are from the Professional Postgraduate Program in Physical Education in National Network at the Federal University of Ceará (ProEF-UFC). Both universities are located in the Northeastern region of Brazil. Findings point to themes related to gender inequality, trans invisibility and/or homophobia, socioeconomic inequalities, reflective-critical issues about democracy and social inclusion, the struggle for social rights, bullying, religions and empathy, intellectual and physical disabilities, diversity, identity, and low self-esteem. A critical education based on social justice is essential in facing the analyzed situations. In conclusion, the notion of social justice can help to promote the knowledge that teacher-researchers mobilize to teach physical education’s thematic subjects in a contextualized and engaged way. This perspective helps to understand the privileges and unjust power relations present in Brazilian society, pointing out subsidies for reflection and deepening of the teaching and learning processes.

Análise do dimorfismo sexual através de índices radiomorfométricos em radiografias panorâmicas

ABSTRACT Sex determination plays a crucial role in the post-mortem identification of human remains. One effective approach for obtaining sex-related data is to use measurements of anatomical structures such as the mandible. This study aimed to evaluate the potential of mandibular radiomorphometric indices from panoramic radiographs (PRs) for the identification of sexual dimorphism. The study sample included 300 PRs of individuals aged 51 to 80 years from the northeastern region of Brazil. Four linear measures and three numerical indices were analyzed with Inkscape® version 1.0.1 for Windows by two blinded evaluators. After statistical analysis, the results showed that the linear measurements obtained from PRs are a reliable method for sex identification. However, the calculated indices of these measurements exhibited lower efficacy for the same purpose. Therefore, PRs proved to be a valuable method for sexual identification through mandibular assessment.

New occurrences of mosquitoes (Diptera: Culicidae) in the Atlantic Forest biome of the Brazilian Northeast.

Information regarding the distribution of Culicidae species in the northeastern region of Brazil is scarce. Immatures were collected from approximately four fragments of the Atlantic Forest. This study presents new occurrences of 18 Culicidae species in Pernambuco state: Anopheles kompi, Georgecraigius fluviatilis, Culex bidens, Culex chidesteri, Culex bastagarius, Culex imitator, Mansonia humeralis, Wyeomyia incaudata, Uranotaenia apicalis, Culex mollis, Culex usquatus, Culex dunni, Culex serratimarge, Culex ybarmis, Culex microphyllus, Sabethes purpureus, Wyeomyia pilicauda, and Wyeomyia airosai. The last nine species were also new records for the northeast region. With the inclusion of these newly recorded species, the total number of mosquitoes documented in Pernambuco state now rises to 94.

Survival and mortality profile among people living with HIV in a cohort in the Northeastern region of Brazil.

Conditions related to the acquired immune deficiency syndrome (AIDS) are still a significant cause of morbidity and mortality among people living with HIV (PLHIV). Longer survival in this population were reported to increase the risk of developing noncommunicable chronic diseases (NCDs). This study aimed to estimate the survival and causes of death according to age group and sex among PLHIV monitored at two referral centers in the Northeastern Brazil. This is a prospective, retrospective cohort with death records from 2007 to 2018, based on a database that registers causes of death using the International Classification of Disease (ICD-10), which were subsequently coded following the Coding Causes of Death in HIV (CoDe). A total of 2,359 PLHIV participated in the study, with 63.2% being men, with a follow-up period of 13.9 years. Annual mortality rate was 1.46 deaths per 100 PLHIV (95% CI: 1.33 - 1.60) with a frequency of 20.9%. Risk of death for men increased by 49% when compared to women, and the risk of death in PLHIV increased by 51% among those aged 50 years and over at the time of diagnosis. It was observed that 73.5% accounted for AIDS-related deaths, 6.9% for non-AIDS defining cancer, 6.3% for external causes, and 3.2% for cardiovascular diseases. Among the youngest, 97.2% presented an AIDS-related cause of death. Highest frequency of deaths from neoplasms was among women and from external causes among men. There is a need for health services to implement strategies ensuring greater adherence to treatment, especially among men and young people. Moreover, screening for chronic diseases and cancer is essential, including the establishment of easily accessible multidisciplinary care centers that can identify and address habits such as illicit drug use and alcoholism, which are associated with violent deaths.

Anticorpos anti-Brucella spp. em equídeos de tração em uma região semiárida do Nordeste do Brasil

ABSTRACT: The present study described the prevalence and factors associated with the seropositivity for anti-Brucella spp. antibodies in working equids in the semiarid regionofnortheastern Brazil. Blood samples were collected from 322 equids (76 horses, 155 mules and 91 donkeys). The Rose Bengal plate test (RBPT) was used as a screening method. Samples that were reactive in the RBPT were tested for confirmation using 2-mercaptoethanol (2-ME) and the standard tube agglutination test (STAT). Overall, 7.1% (23/322) of the samples were positive according to the RBPT. After confirmatory tests, the prevalence of brucellosis was found to be 6.5% (21/322). Among these cases, 33.3% (7/21) were horses, 42.8% (9/21) were mules and 23.9% (5/21) were donkeys. In the multivariate analysis, age over 10 years was considered to be a factor associated with the seropositivity (OR: 17.17; 95% CI: 2.582-164.7, P = 0.006) for anti-Brucella spp. antibodies. The significant prevalence of anti-Brucella spp. antibodies found in working equids and the wide distribution of positive animals demonstrates a worrying epidemiological situation regarding brucellosis in the study region. Age over 10 years was a risk factor associated with the seropositivity for anti-Brucella spp. antibodies in animals.

Determining the effective elastic thickness through cross-correlation between isostatic disturbances

The elastic thickness parameter was estimated using the mobile correlation technique between the observed isostatic disturbance and the gravity disturbance calculated through direct gravimetric modeling. We computed the vertical flexure value of the crust for a specific elastic thickness using a given topographic dataset. The gravity disturbance due to the topography was determined after the calculation. A grid of values for the elastic thickness parameter was generated. Then, a moving correlation was performed between the observed gravity data (representing actual surface data) and the calculated data from the forward modeling. The optimum elastic thickness of the particular point corresponded to the highest correlation coefficient. The methodology was tested on synthetic data and showed that the synthetic depth closely matched the original depth, including the elastic thickness value. To validate the results, the described procedure was applied to a real dataset from the Barreirinhas Basin, situated in the northeastern region of Brazil. The results show that the obtained crustal depth is highly correlated with the depth from known models. Additionally, we noted that the elastic thickness behaves as expected, decreasing from the continent towards the ocean. Based on the results, this method has the potential to be employed as a direct estimate of crustal depth and elastic thickness for any region.

Coat color in Thylamys karimii (Petter, 1968) (Didelphimorphia, Didelphidae) in northeastern Brazil: intraspecific variation and geographic distribution

ABSTRACT Knowledge of Didelphidae taxonomy and diversity has increased steadily over the last decades, mainly due to increasing collection efforts and revisionary works. Yet, especially for mouse opossums, a proper appraisal of morphological variation is still incipient. Thylamys karimii occurs in the Brazilian biomes of Caatinga and Cerrado, and specimens with two different shades of dorsal coloration (brown and gray) were recently documented in sympatry in the Parque Nacional (PARNA) do Catimbau (Caatinga biome). We used qualitative and morphometric data from skulls and skins (n = 7 from PARNA Catimbau and n = 26 from other localities) to compare these two coat color morphotypes and characterize the morphological diversity and taxonomic status of the Caatinga populations. We used Student’s t-tests to compare sexes and morphotypes’ measurements. We found at least three well-defined coat color morphotypes distinguishable by dorsal and ventral coloration and not restricted to PARNA Catimbau. Variation of the other morphological traits suggests that these morphotypes are more likely a case of intraspecific variation in the Brazilian northeastern region. Morphometric differences, particularly between coat color morphotypes, might be better elucidated in larger samples. Additionally, these specimens represent an important extension of the species’ known distribution reaching the Atlantic Forest borders.