Biogeochemical indicators of environmental changes from 50Ka to 10Ka in a humid region of the Brazilian Amazon

A total of 187 different species of arboviruses and other viruses in vertebrates were identified at the Evandro Chagas Institute (IEC) from 1954 to 1998, among more than 10,000 arbovirus strains isolated from humans, hematophagous insects, and wild and sentinel vertebrates. Despite intensive studies in the Brazilian Amazon region, especially in Pará State, very little is known about most of these viruses, except for information on date, time, source, and method of isolation, as well as their capacity to infect laboratory animals. This paper reviews ecological and epidemiological data and analyzes the impact of vector and host population changes on various viruses as a result of profound changes in the natural environment. Deforestation, mining, dam and highway construction, human colonization, and urbanization were the main manmade environmental changes associated with the emergence and/or reemergence of relevant arboviruses, including some known pathogens for humans.

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Study on Chagas disease occurrence in the municipality of Monte Negro, State of Rondônia, Brazilian Amazon

Revista da Sociedade Brasileira de Medicina Tropical ◽

10.1590/s0037-86822011000600010 ◽

2011 ◽

Vol 44 (6) ◽

pp. 703-707 ◽

Cited By ~ 4

Author(s):

Elaine Oliveira Costa de Carvalho ◽

João Aristeu da Rosa ◽

Anderson Antonio de Carvalho ◽

Hialli Cristine Oliveira Chaves ◽

Everton Almeida de Souza ◽

...

Keyword(s):

Chagas Disease ◽

Environmental Changes ◽

Brazilian Amazon ◽

Human Infection ◽

Blood Collection ◽

Behavior Changes ◽

Disease Occurrence ◽

Random Samples ◽

Low Prevalence ◽

Vector Behavior

INTRODUCTION: Studies on Chagas disease deal with the perspective of its occurrence in the Amazon region, which is directly correlated to the population growth and the spread of the bug biotope. The state of Rondônia has an immense source of vectors (Triatomine) and reservoirs of Trypanosoma cruzi. Environmental changes brought forth by the deforestation in the region may cause vector behavior changes and bring these vectors to a closer contact with humans, increasing the probability of vector infection. METHODS: This study was carried out to check the occurrence of Chagas disease in the municipality of Monte Negro, Rondônia, Brazil, based on a random sampling of the farms and people wherein blood collection from the population and capturing triatomines were done. The blood samples were submitted to serologic tests to detect antibodies of the IgG class against T. cruzi. The triatomines that were collected had their digestive tract checked for the presence of trypanosomatidae with morphology resembling that of the T. cruzi. RESULTS: The population examined was mostly from other states. From the 322 bugs examined on the microscope, 50% showed parasites with morphology compatible with T. cruzi. From the serology of 344 random samples of human blood, 1.2% was found positive, 6% showed inconclusive results, and 92.8% were negative. CONCLUSIONS: Monte Negro shows low prevalence of human infection by T. cruzi and none active vector transmission; however, preventive and surveying measures, which are not performed until now, shall be taken due to the abundance of vectors infected by trypanosomatidae.

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Environmental Changes And Malaria In The Brazilian Amazon Region: An Ecological Study Between 1990 And 2012

ISEE Conference Abstracts ◽

10.1289/isee.2015.2015-639 ◽

2015 ◽

Vol 2015 (1) ◽

pp. 639

Author(s):

Priscilla Perez Da Silva Pereira ◽

Fabiana Araujo Figueiredo Da Mata ◽

Keitty Regina Cordeiro De Andrade ◽

Ana Cláudia Godoy Figueiredo ◽

Mauricio Gomes Pereira

Keyword(s):

Ecological Study ◽

Environmental Changes ◽

Brazilian Amazon ◽

Amazon Region ◽

Brazilian Amazon Region

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Impact of environmental changes on the behavioral diversity of the Odonata (Insecta) in the Amazon

Scientific Reports ◽

10.1038/s41598-021-88999-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Bethânia O. de Resende ◽

Victor Rennan S. Ferreira ◽

Leandro S. Brasil ◽

Lenize B. Calvão ◽

Thiago P. Mendes ◽

...

Keyword(s):

Environmental Changes ◽

Brazilian Amazon ◽

Primary Objective ◽

Conservation Strategies ◽

Behavioral Repertoire ◽

Behavioral Traits ◽

Behavioral Diversity ◽

First Response ◽

Wide Range ◽

Abiotic Variables

AbstractThe odonates are insects that have a wide range of reproductive, ritualized territorial, and aggressive behaviors. Changes in behavior are the first response of most odonate species to environmental alterations. In this context, the primary objective of the present study was to assess the effects of environmental alterations resulting from shifts in land use on different aspects of the behavioral diversity of adult odonates. Fieldwork was conducted at 92 low-order streams in two different regions of the Brazilian Amazon. To address our main objective, we measured 29 abiotic variables at each stream, together with five morphological and five behavioral traits of the resident odonates. The results indicate a loss of behaviors at sites impacted by anthropogenic changes, as well as variation in some morphological/behavioral traits under specific environmental conditions. We highlight the importance of considering behavioral traits in the development of conservation strategies, given that species with a unique behavioral repertoire may suffer specific types of extinction pressure.

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Anatophysiology of Vouacapoua americana Aubl. in the juvenile phase: A species included in the IUCN red list of threatened species

Research Society and Development ◽

10.33448/rsd-v10i3.12960 ◽

2021 ◽

Vol 10 (3) ◽

pp. e4510312960

Author(s):

Solange Henchen Trevisan ◽

Raírys Cravo Herrera ◽

Thiago Bernardi Vieira ◽

Maike Vieira Drosdosky ◽

Roberto Lisboa Cunha ◽

...

Keyword(s):

Environmental Changes ◽

Brazilian Amazon ◽

Steam Pressure ◽

Iucn Red List ◽

Central Vein ◽

Physiological Changes ◽

Dry Period ◽

Secretory Structures ◽

Stage Of Development ◽

Arc Shape

The Amazon is undergoing environmental changes that can cause morphological and physiological changes in plants. The general objective of this study was to evaluate the anatomical and eco-physiological features of Vouacapoua americana during development in the Brazilian Amazon. It was observed that the stomata only occur in the abaxial face. Secretory structures are present throughout the leaf blade. In the central vein and petiole region it was observed that the xylem occupies the vein’s central part, presenting an arc shape. The eco-physiological evaluations revealed that the dry period presented higher values of leaf temperature and steam pressure deficit, and lower values of leaf humidity, stomatal conductance, and transpiration. Anatomical and physiological differences occur at each stage of development.

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Centromochlus meridionalis, a new catfish species from the southern Amazonian limits, Mato Grosso State, Brazil (Siluriformes: Auchenipteridae)

Neotropical Ichthyology ◽

10.1590/s1679-62252013000400007 ◽

2013 ◽

Vol 11 (4) ◽

pp. 797-808 ◽

Cited By ~ 6

Author(s):

Luisa Maria Sarmento-Soares ◽

Fernando G. Cabeceira ◽

Lucélia Nobre Carvalho ◽

Jansen Zuanon ◽

Alberto Akama

Keyword(s):

New Species ◽

Anterior Margin ◽

Environmental Changes ◽

Conservation Status ◽

Brazilian Amazon ◽

Mato Grosso ◽

The Third ◽

Dorsal Fin ◽

Species Being ◽

Eleven Species

Centromochlus actually comprises eleven species, being the most problematic genus among the Centromochlinae, including morphologically heterogeneous taxa. The Centromochlus species have a wide distributional area on northern South America. Centromochlus meridionalis, new species, is described from headwaters of rio Teles Pires, contributor of rio Tapajós, Mato Grosso State, Brazil, and represents one of the southernmost records of a centromochlin catfish for Meridional Amazon rivers. Centromochlus meridionalis is promptly distinguished from its congeners by the small orbital diameter (relative to head length), and also by the combination of absence of first nuchal plate, anterior margin of dorsal-fin spine smooth, six branched rays in anal fin, seven pairs of ribs and 34 vertebrae. They are small sized catfishes with adults between 33 to 61 mm in standard length. The modified male anal fin is conspicuous, with the third unbranched ray enlarged, about twice the width of first unbranched ray. The new species inhabits a region strongly endangered by environmental changes due to expansion of agropecuary activities on Brazilian Amazon, which include this species in an uncertain situation regarding the conservation status of its natural population.

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Environmental changes during the last millennium based on multi-proxy palaeoecological records in a savanna-forest mosaic from the northernmost Brazilian Amazon region

Anais da Academia Brasileira de Ciências ◽

10.1590/0001-3765201520130074 ◽

2015 ◽

Vol 87 (3) ◽

pp. 1623-1651 ◽

Cited By ~ 4

Author(s):

MARIA ECILENE N.S. MENESES ◽

MARCONDES L. COSTA ◽

DIRK ENTERS ◽

HERMANN BEHLING

Keyword(s):

Environmental Changes ◽

Sediment Cores ◽

Brazilian Amazon ◽

Climatic Conditions ◽

Amazon Region ◽

Fossil Pollen ◽

Forest Expansion ◽

Additional Information ◽

Brazilian Amazon Region ◽

Forest Mosaic

ABSTRACTThe environmental changes and the dynamics of the savanna-forest mosaic, over the last 1050 years, have been reconstructed by pollen, charcoal, radiocarbon dating mineralogical and geochemical analyses of sediment cores taken from three different Mauritia flexuosapalm swamps in the northernmost part of the Brazilian Amazon region (northern state of Roraima). Studies on the relationship between the modern pollen rain and the regional vegetation provide additional information for the interpretation of the fossil pollen records. The fossil pollen assemblages and geochemical results indicate relatively wet climatic conditions throughout the recorded period. Despite these moist conditions, fires were frequent and are one of the reasons for the dominance of a grassy savanna instead of forest expansion in the study area. Considering the generally wet climatic conditions, these fires were most likely caused by human activities. Even today, fires hinder forest expansion into savanna areas. Sandy hydromorphic soils may also act as an edaphic control to maintain the current sharp boundary between forest and savanna ecosystems.

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The effect of different logging regimes on the ecomorphological structure of stream fish assemblages in the Brazilian Amazon

Hydrobiologia ◽

10.1007/s10750-020-04508-3 ◽

2021 ◽

Vol 848 (5) ◽

pp. 1027-1039

Author(s):

Laís L. Jacob ◽

Bruno S. Prudente ◽

Luciano F. A. Montag ◽

Rogério R. Silva

Keyword(s):

Environmental Changes ◽

Fish Assemblages ◽

Brazilian Amazon ◽

Habitat Characteristics ◽

Stream Fish ◽

Relative Width ◽

Human Disturbances ◽

Undisturbed Forest ◽

Stream Fish Assemblages ◽

Habitat Variables

AbstractWe evaluated the effects of changes in habitat structure resulting from conventional logging (CL) and reduced-impact logging (RIL) on the ecomorphological structure of stream fish assemblages in the eastern Brazilian Amazon, investigating (1) which habitat characteristics are influenced by different logging methods, (2) the differences in the ecomorphological structure of fish assemblages between two logging methods and undisturbed forest (UF), and (3) the relationships between ecomorphological traits of fish assemblages and habitat variables. We measured 13 habitat variables and characterized 11 ecomorphological traits of 55 fish species collected in 34 sampling sites (stream stretches) located in CL, RIL, and UF. In logged areas, the streams present a fine sediment increase and reduced vegetation cover, while in the UF a greater amount of natural shelter and more cover vegetation were observed. These environmental changes selected ecomorphological traits of stream fish assemblages, recording a greater relative width of the mouth in UF, higher ventral flattening index in RIL, or greater relative head length, and higher caudal peduncle compression index in CL. In this sense, we recommend that logging practices, including RIL, should be reviewed as a means of adopting better strategies to minimize human disturbances in streams.

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Linking transcription, RNA polymerase II elongation and alternative splicing

Biochemical Journal ◽

10.1042/bcj20200475 ◽

2020 ◽

Vol 477 (16) ◽

pp. 3091-3104 ◽

Cited By ~ 1

Author(s):

Luciana E. Giono ◽

Alberto R. Kornblihtt

Keyword(s):

Gene Expression ◽

Alternative Splicing ◽

Rna Polymerase Ii ◽

Environmental Changes ◽

Transcription Elongation ◽

Single Gene ◽

Regulation Of Gene Expression ◽

Regulation Of Transcription ◽

Stepping Stones ◽

Eukaryotic Transcription

Gene expression is an intricately regulated process that is at the basis of cell differentiation, the maintenance of cell identity and the cellular responses to environmental changes. Alternative splicing, the process by which multiple functionally distinct transcripts are generated from a single gene, is one of the main mechanisms that contribute to expand the coding capacity of genomes and help explain the level of complexity achieved by higher organisms. Eukaryotic transcription is subject to multiple layers of regulation both intrinsic — such as promoter structure — and dynamic, allowing the cell to respond to internal and external signals. Similarly, alternative splicing choices are affected by all of these aspects, mainly through the regulation of transcription elongation, making it a regulatory knob on a par with the regulation of gene expression levels. This review aims to recapitulate some of the history and stepping-stones that led to the paradigms held today about transcription and splicing regulation, with major focus on transcription elongation and its effect on alternative splicing.

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Seeking to uncover biology's chemical roots

Emerging Topics in Life Sciences ◽

10.1042/etls20190012 ◽

2019 ◽

Vol 3 (5) ◽

pp. 435-443 ◽

Cited By ~ 3

Author(s):

Addy Pross

Keyword(s):

Environmental Changes ◽

Biological Systems ◽

Significant Development ◽

The Road ◽

Physical Chemical ◽

Systems Chemistry ◽

Biological World ◽

Inanimate Matter ◽

The Origin Of Life ◽

Opening Up

Despite the considerable advances in molecular biology over the past several decades, the nature of the physical–chemical process by which inanimate matter become transformed into simplest life remains elusive. In this review, we describe recent advances in a relatively new area of chemistry, systems chemistry, which attempts to uncover the physical–chemical principles underlying that remarkable transformation. A significant development has been the discovery that within the space of chemical potentiality there exists a largely unexplored kinetic domain which could be termed dynamic kinetic chemistry. Our analysis suggests that all biological systems and associated sub-systems belong to this distinct domain, thereby facilitating the placement of biological systems within a coherent physical/chemical framework. That discovery offers new insights into the origin of life process, as well as opening the door toward the preparation of active materials able to self-heal, adapt to environmental changes, even communicate, mimicking what transpires routinely in the biological world. The road to simplest proto-life appears to be opening up.

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