Comparative cytogenetic analysis of two grasshopper species of the tribe Abracrini (Ommatolampinae, Acrididae)

The grasshopper species Orthoscapheus rufipes and Eujivarus fusiformis were analyzed using several cytogenetic techniques. The karyotype of O. rufipes, described here for the first time, had a diploid number of 2n = 23, whereas E. fusiformis had a karyotype with 2n = 21. The two species showed the same mechanism of sex determination (XO type) but differed in chromosome morphology. Pericentromeric blocks of constitutive heterochromatin (CH) were detected in the chromosome complement of both species. CMA3/DA/DAPI staining revealed CMA3-positive blocks in CH regions in four autosomal bivalents of O. rufipes and in two of E. fusiformis. The location of active NORs differed between the two species, occurring in bivalents M6 and S9 of O. rufipes and M6 and M7 of E. fusiformsi. The rDNA sites revealed by FISH coincided with the number and position of the active NORs detected by AgNO3 staining. The variability in chromosomal markers accounted for the karyotype differentiation observed in the tribe Abracrini

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Nutritional assessment methods for zinc supplementation in prepubertal non-zinc-deficient children

Background: Zinc is an essential nutrient that is required for numerous metabolic functions, and zinc deficiency results in growth retardation, cell-mediated immune dysfunction, and cognitive impairment. Objective: This study evaluated nutritional assessment methods for zinc supplementation in prepubertal non-zinc-deficient children. Design: We performed a randomised, controlled, triple-blind study. The children were divided into a control group (10% sorbitol, n=31) and an experimental group (10 mg Zn/day, n=31) for 3 months. Anthropometric and dietary assessments as well as bioelectrical measurements were performed in all children. Results: Our study showed (1) an increased body mass index for age and an increased phase angle in the experimental group; (2) a positive correlation between nutritional assessment parameters in both groups; (3) increased soft tissue, and mainly fat-free mass, in the body composition of the experimental group, as determined using bioelectrical impedance vector analysis; (4) increased consumption of all nutrients, including zinc, in the experimental group; and (5) an increased serum zinc concentration in both groups (p<0.0001). Conclusions: Given that a reference for body composition analysis does not exist for intervention studies, longitudinal studies are needed to investigate vector migration during zinc supplementation. These results reinforce the importance of employing multiple techniques to assess the nutritional status of populations

Visceral leishmaniasis: a study on phlebotomine sand flies and canine infection in Montes Claros, State of Minas Gerais.

A leishmaniose visceral no Brasil estava inicialmente associada a áreas rurais, mas devido às diversas alterações no ambiente como, desmatamentos, urbanização e intenso processo migratório, ocorreu a expansão das áreas endêmicas, levando à urbanização da doença, principalmente nas regiões Sudeste e Centro Oeste do país. No município de Montes Claros, situado ao norte de Minas Gerais, foi feito um estudo para verificação da situação da LV. No ano de 2002 foi realizado inquérito sorológico canino e no período de setembro de 2002 a agosto de 2003 foi feito levantamento entomológico, utilizando armadilhas luminosas de CDC. A prevalência da LV canina apresentou taxa média de infecção em torno de 5%. A fauna de flebotomíneos estimada foi de 16 espécies, totalizando 1043 exemplares. Lutzomyia longipalpis foi a espécie predominante com 74%, o que sugere a sua participação na transmissão de LV em Montes Claros.Visceral leishmaniasis in Brazil was initially associated with rural areas. However, due to several environmental modifications such as deforestation, urbanization and intense migratory processes, there has been an expansion of endemic areas, leading to urbanization of the disease, mainly in the central and northeastern regions of Brazil. In the municipality of Montes Claros, located in the north of the state of Minas Gerais, an epidemiological survey on VL was carried out. A canine serological inquiry was carried out in 2002 and an entomological survey, using luminous CDC traps, was performed from September 2002 to August 2003. Canine VL prevalence showed an average infection rate of approximately 5%. An estimated 16 species comprised the phlebotomine sand fly fauna, based on a total of 1043 specimens. The predominant species was Lutzomyia longipalpis with a rate of 74%, suggesting its participation in the transmission of VL in the municipality of Montes Claros