scholarly journals Indoor Dust as a Source of Virulent Strains of the Agents of Cryptococcosis in the Rio Negro Micro-Region of the Brazilian Amazon

2020 ◽  
Vol 8 (5) ◽  
pp. 682
Author(s):  
Fábio Brito-Santos ◽  
Luciana Trilles ◽  
Carolina Firacative ◽  
Bodo Wanke ◽  
Filipe Anibal Carvalho-Costa ◽  
...  
Keyword(s):  
Galleria Mellonella ◽  
Brazilian Amazon ◽  
Vancouver Island ◽  
Indoor Dust ◽  
Continuous Exposure ◽  
Pathogenic Potential ◽  
Rio Negro ◽  
Species Complexes ◽  
Virulent Strains ◽  
The Impact

Cryptococcosis, a potentially fatal mycosis in humans, is acquired via exposure to exogenous environmental sources. This study aimed to investigate the frequency, genetic diversity, and virulence of cryptococcal strains isolated from indoor dust in the Rio Negro micro-region of the Brazilian Amazon. A total of 8.9% of the studied houses were positive, recovering nine Cryptococcus neoformans VNI and 16 C. gattii VGII isolates, revealing an endemic pattern in domestic microenvironments. The International Society for Human and Animal Mycology (ISHAM) consensus multilocus sequence typing (MLST) scheme for the C. neoformans/C. gattii species complexes identified two sequence types (STs), ST93 and ST5, amongst C. neoformans isolates and six STs amongst C. gattii isolates, including the Vancouver Island Outbreak ST7 (VGIIa) and ST20 (VGIIb), the Australian ST5, and ST264, ST268 and ST445, being unique to the studied region. Virulence studies in the Galleria mellonella model showed that five C. gattii strains and one C. neoformans strain showed a similar pathogenic potential to the highly virulent Vancouver Island outbreak strain CDR265 (VGIIa). The findings of this study indicate that humans can be exposed to the agents of cryptococcosis via house dust, forming the basis for future studies to analyze the impact of early and continuous exposure to indoor dust on the development of subclinical or clinical infections.

scholarly journals Moroccan Propolis: A Natural Antioxidant, Antibacterial, and Antibiofilm against Staphylococcus aureus with No Induction of Resistance after Continuous Exposure

2018 ◽  
Vol 2018 ◽  
pp. 1-19 ◽  
Author(s):  
Soukaïna El-Guendouz ◽  
Smail Aazza ◽  
Badiaa Lyoussi ◽  
Vassya Bankova ◽  
Milena Popova ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Quorum Sensing ◽  
Galleria Mellonella ◽  
Antioxidant Activities ◽  
Bacterial Biofilm ◽  
Continuous Exposure ◽  
Dependent Manner ◽  
Propolis Extract ◽  
Two Samples ◽  
The Impact

This study was performed to evaluate the total phenols, flavonoids, and antioxidant activities of twenty-four propolis samples from different regions of Morocco. In addition, two samples were screened regarding the antibacterial effect against four Staphylococcus aureus strains. Gas chromatography coupled to mass spectra (GC-MS) analysis was done for propolis samples used in antibacterial tests. The minimum inhibitory and minimum bactericidal concentration (MIC, MBC) were determined. The potential to acquire the resistance after sequential exposure of bacterial strains and the impact of adaptation to propolis on virulence using the Galleria mellonella were evaluated. Additionally, the effects of propolis extract on the bacterial adherence ability and its ability to inhibit the quorum sensing activity were also examined. Among the twenty-four extracts studied, the samples from Sefrou, Outat el Haj, and the two samples marketed in Morocco were the best for scavenging DPPH, ABTS, NO, peroxyl, and superoxide radicals as well as in scavenging of hydrogen peroxide. A strong correlation was found between the amounts of phenols, flavonoids, and antioxidant activities. Propolis extract at the MIC value (0.36 mg/mL) significantly reduced (p < 0.001) the virulence potential of S. aureus ATCC 6538 and the MRSA strains without leading to the development of resistance in the sequence of continuous exposure. It was able to impair the bacterial biofilm formation. The results have revealed that sample 1 reduces violacein production in a concentration dependent manner, indicating inhibition of quorum sensing. This extract has as main group of secondary metabolites flavonoids (31.9%), diterpenes (21.5%), and phenolic acid esters (16.5%).

scholarly journals Surgical Site Infection Following Caesarean Section by Acinetobacter Species: A Report from a Hyperendemic Setting in the Brazilian Amazon Region

2021 ◽  
Vol 9 (4) ◽  
pp. 743
Author(s):  
Blenda Gonçalves Cabral ◽  
Danielle Murici Brasiliense ◽  
Ismari Perini Furlaneto ◽  
Yan Corrêa Rodrigues ◽  
Karla Valéria Batista Lima
Keyword(s):  
Caesarean Section ◽  
Surgical Site Infection ◽  
Carbapenem Resistance ◽  
Brazilian Amazon ◽  
Amazon Region ◽  
Site Infection ◽  
Acinetobacter Species ◽  
Brazilian Amazon Region ◽  
Acinetobacter Spp ◽  
The Impact

Surgical site infection (SSI) following caesarean section is associated with increased morbidity, mortality, and significant health care costs. This study evaluated the epidemiological, clinical, and microbiological features of Acinetobacter spp. in women with SSIs who have undergone caesarean section at a referral hospital in the Brazilian Amazon region. This study included 69 women with post-caesarean SSI by Acinetobacter spp. admitted to the hospital between January 2012 and May 2015. The 69 Acinetobacter isolates were subjected to molecular species identification, antimicrobial susceptibility testing, detection of carbapenemase-encoding genes, and genotyping. The main complications of post-caesarean SSI by Acinetobacter were inadequate and prolonged antibiotic therapy, sepsis, prolonged hospitalization, and re-suture procedures. A. baumannii, A. nosocomialis and A. colistiniresistens species were identified among the isolates. Carbapenem resistance was associated with OXA-23-producing A. baumannii isolates and IMP-1-producing A. nosocomialis isolate. Patients with multidrug-resistant A. baumannii infection showed worse clinical courses. Dissemination of persistent epidemic clones was observed, and the main clonal complexes (CC) for A. baumannii were CC231 and CC236 (Oxford scheme) and CC1 and CC15 (Pasteur scheme). This is the first report of a long-term Acinetobacter spp. outbreak in women who underwent caesarean section at a Brazilian hospital. This study demonstrates the impact of multidrug resistance on the clinical course of post-caesarean infections.

scholarly journals The association between a conditional cash transfer programme and malaria incidence: a longitudinal ecological study in the Brazilian Amazon between 2004 and 2015

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Layana Costa Alves ◽  
Mauro Niskier Sanchez ◽  
Thomas Hone ◽  
Luiz Felipe Pinto ◽  
Joilda Silva Nery ◽  
...  
Keyword(s):  
Fixed Effects ◽  
Negative Binomial ◽  
Malaria Incidence ◽  
Panel Study ◽  
Negative Binomial Regression ◽  
Brazilian Amazon ◽  
Conditional Cash Transfer ◽  
Cash Transfer ◽  
Percentage Point Increase ◽  
The Impact

Abstract Background Malaria causes 400 thousand deaths worldwide annually. In 2018, 25% (187,693) of the total malaria cases in the Americas were in Brazil, with nearly all (99%) Brazilian cases in the Amazon region. The Bolsa Família Programme (BFP) is a conditional cash transfer (CCT) programme launched in 2003 to reduce poverty and has led to improvements in health outcomes. CCT programmes may reduce the burden of malaria by alleviating poverty and by promoting access to healthcare, however this relationship is underexplored. This study investigated the association between BFP coverage and malaria incidence in Brazil. Methods A longitudinal panel study was conducted of 807 municipalities in the Brazilian Amazon between 2004 and 2015. Negative binomial regression models adjusted for demographic and socioeconomic covariates and time trends were employed with fixed effects specifications. Results A one percentage point increase in municipal BFP coverage was associated with a 0.3% decrease in the incidence of malaria (RR = 0.997; 95% CI = 0.994–0.998). The average municipal BFP coverage increased 24 percentage points over the period 2004–2015 corresponding to be a reduction of 7.2% in the malaria incidence. Conclusions Higher coverage of the BFP was associated with a reduction in the incidence of malaria. CCT programmes should be encouraged in endemic regions for malaria in order to mitigate the impact of disease and poverty itself in these settings.

scholarly journals Inadequate management of natural ecosystem in the Brazilian Amazon region results in the emergence and reemergence of arboviruses

2001 ◽  
Vol 17 (suppl) ◽  
pp. S155-S164 ◽  
Author(s):  
Pedro F. C. Vasconcelos ◽  
Amélia P. A. Travassos da Rosa ◽  
Sueli G. Rodrigues ◽  
Elizabeth S. Travassos da Rosa ◽  
Nicolas Dégallier ◽  
...  
Keyword(s):  
Environmental Changes ◽  
Epidemiological Data ◽  
Brazilian Amazon ◽  
Host Population ◽  
Amazon Region ◽  
Laboratory Animals ◽  
Natural Ecosystem ◽  
Brazilian Amazon Region ◽  
Mining Dam ◽  
The Impact

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.

scholarly journals BrpA Is Involved in Regulation of Cell Envelope Stress Responses in Streptococcus mutans

2012 ◽  
Vol 78 (8) ◽  
pp. 2914-2922 ◽  
Author(s):  
J. P. Bitoun ◽  
S. Liao ◽  
X. Yao ◽  
S.-J. Ahn ◽  
R. Isoda ◽  
...  
Keyword(s):  
Streptococcus Mutans ◽  
Stress Responses ◽  
Antimicrobial Agents ◽  
Galleria Mellonella ◽  
Cell Envelope ◽  
Luciferase Reporter ◽  
Luciferase Reporter Gene ◽  
Content Type ◽  
Lipid Ii ◽  
The Impact

ABSTRACTPrevious studies have shown that BrpA plays a major role in acid and oxidative stress tolerance and biofilm formation byStreptococcus mutans. Mutant strains lacking BrpA also display increased autolysis and decreased viability, suggesting a role for BrpA in cell envelope integrity. In this study, we examined the impact of BrpA deficiency on cell envelope stresses induced by envelope-active antimicrobials. Compared to the wild-type strain UA159, the BrpA-deficient mutant (TW14D) was significantly more susceptible to antimicrobial agents, especially lipid II inhibitors. Several genes involved in peptidoglycan synthesis were identified by DNA microarray analysis as downregulated in TW14D. Luciferase reporter gene fusion assays also revealed that expression ofbrpAis regulated in response to environmental conditions and stresses induced by exposure to subinhibitory concentrations of cell envelope antimicrobials. In aGalleria mellonella(wax worm) model, BrpA deficiency was shown to diminish the virulence ofS. mutansOMZ175, which, unlikeS. mutansUA159, efficiently kills the worms. Collectively, these results suggest that BrpA plays a role in the regulation of cell envelope integrity and that deficiency of BrpA adversely affects the fitness and diminishes the virulence of OMZ175, a highly invasive strain ofS. mutans.

Reproductive-cycle plasticity in yellow-cedar (Chamaecyparisnootkatensis)

1991 ◽  
Vol 21 (9) ◽  
pp. 1360-1364 ◽  
Author(s):  
Y. A. El-Kassaby ◽  
J. Maze ◽  
D. A. MacLeod ◽  
S. Banerjee
Keyword(s):  
Reproductive Cycle ◽  
Vancouver Island ◽  
Significant Delay ◽  
Continue Development ◽  
Cold Temperatures ◽  
Size And Shape ◽  
Seed Extraction ◽  
Fresh Pollen ◽  
The Impact

In 1987, a study was initiated to determine the properties of seed from apparently premature cones of yellow-cedar (Chamaecyparisnootkatensis (D. Don) Spach) on southwestern Vancouver Island. After pollination with fresh pollen in February, all cones showed signs of maturation (i.e., drying and shedding) by December. Samples of these 1-year-old cones were collected for seed extraction and germination tests. Germination ranged between 10 and 42% for isolated cones (i.e., bagged) and between 0 and 25% for unisolated cones. Similar germination results were obtained for the 1988 and 1989 cone crops. Anatomical observations revealed that the 10-month-old embryos were similar in both size and shape to embryos from 2-year-old seeds. It was concluded that transplanting yellow-cedar trees to warmer, low-elevation sites enabled seed cones to continue development without significant delay caused by dormancy induced by cold temperatures at higher elevations. This alteration of normal phenology reflects the impact of environmental contingencies on development.

scholarly journals Look Upstream: Measurement for Innovation on the Upper Rio Negro of the Amazon Basin

2021 ◽  
Vol 8 ◽  
Author(s):  
Kurt Shaw ◽  
Rita de Cácia Oenning da Silva
Keyword(s):  
Amazon Basin ◽  
Controlled Trial ◽  
Theory Of Change ◽  
Positive Development ◽  
Private Goods ◽  
Rio Negro ◽  
The Government ◽  
Traditional Songs ◽  
The Impact

The growth of the randomized controlled trial (RCT) as the “gold standard” for evaluation has justly been praised as an advance in the professionalization of social programs and projects, an “adoption of science” - in the words of the Lancet. None the less, the emphasis on the RCT biases funding for projects that distribute private goods and which focus on “low hanging fruit” in health, nutrition, and sanitation, simply because those areas lend themselves to the sort of measurement that works with RCTs. As a result, many project developers in the government and NGO sectors lament that a hegemonic focus on RCTs impedes creativity or new models that challenge traditional paradigms. This case study of CanalCanoa, a community video coaching project for indigenous parents of young children in the Rio Negro region of the Amazon Basin, offers techniques to measure for innovation. Instead of developing a new RCT for an extremely diverse population (27 ethnic groups) where traditional childcare methods are in historical flux because of urbanization, CanalCanoa measured variables shown by previous RCTs to be causally connected with positive development results. By researching the impact of the intervention on nutrition, language (multilingualism, use of traditional songs and stories), and social network expansion, CanalCanoa measured upstream indicators, thus mixing scientific rigor with an opportunity for innovation and providing important insight and reform of a theory of change.

Influence of pesticides, soil temperature and moisture on entomopathogenic nematodes from southern Benin and control of underground termite nest populations

Nematology ◽  
2015 ◽  
Vol 17 (9) ◽  
pp. 1057-1069 ◽  
Author(s):  
Hugues Baimey ◽  
Lionel Zadji ◽  
Leonard Afouda ◽  
Maurice Moens ◽  
Wilfrida Decraemer
Keyword(s):  
Soil Moisture ◽  
Soil Temperature ◽  
Entomopathogenic Nematodes ◽  
Galleria Mellonella ◽  
Macrotermes Bellicosus ◽  
And Control ◽  
The Impact ◽  
Termite Nest ◽  
Southern Benin ◽  
Soil Temperature And Moisture

The influence of three pesticides on the viability and infectivity of four Beninese isolates of entomopathogenic nematodes (EPN), Heterorhabditis indica Ayogbe1, H. sonorensis Azohoue2, H. sonorensis Ze3, and Steinernema sp. Bembereke, was determined. The impact of both soil temperature and soil moisture on the virulence of these EPN to Trinervitermes occidentalis was investigated in laboratory assays. The effect of EPN-infected Galleria mellonella larvae on underground populations of Macrotermes bellicosus was also examined. All tested Heterorhabditis species were more tolerant to glyphosate and fipronil than the Steinernema species. Heterorhabditis sonorensis Azohoue2, showed the best results with 63.2% termite mortality at a soil temperature of 35°C. The increase of soil moisture to 20% (w/w) did not negatively influence the virulence of tested EPN. The underground populations of 71% or 60% treated nests were controlled by H. sonorensis Azohoue2- or H. indica Ayogbe1-infected G. mellonella larvae, respectively.

scholarly journals Pathogenicity Levels of Colombian Strains of Candida auris and Brazilian Strains of Candida haemulonii Species Complex in Both Murine and Galleria mellonella Experimental Models

2020 ◽  
Vol 6 (3) ◽  
pp. 104
Author(s):  
Julián E. Muñoz ◽  
Laura M. Ramirez ◽  
Lucas dos Santos Dias ◽  
Laura A. Rivas ◽  
Lívia S. Ramos ◽  
...  
Keyword(s):  
Survival Rate ◽  
Species Complex ◽  
Galleria Mellonella ◽  
Experimental Models ◽  
Candida Auris ◽  
Candida Haemulonii ◽  
Virulent Strains ◽  
Inert Surface ◽  
Phagocytosis Index ◽  
Different Levels

Candida auris and Candida haemulonii complex (C. haemulonii, C. haemulonii var. vulnera and C. duobushaemulonii) are phylogenetically related species that share some physiological features and habits. In the present study, we compared the virulence of these yeast species using two different experimental models: (i) Galleria mellonella larvae to evaluate the survival rate, fungal burden, histopathology and phagocytosis index and (ii) BALB/c mice to evaluate the survival. In addition, the fungal capacity to form biofilm over an inert surface was analyzed. Our results showed that in both experimental models, the animal survival rate was lower when infected with C. auris strains than the C. haemulonii species complex. The hemocytes of G. mellonella showed a significantly reduced ability to phagocytize the most virulent strains forming the C. haemulonii species complex. Interestingly, for C. auris, it was impossible to measure the phagocytosis index due to a general lysis of the hemocytes. Moreover, it was observed a greater capability of biofilm formation by C. auris compared to C. haemulonii species complex. In conclusion, we observed that C. auris and C. haemulonii complex have different levels of pathogenicity in the experimental models employed in the present study.

The effects of uncertain forest conservation benefits on long-run deforestation in the Brazilian Amazon

2018 ◽  
Vol 23 (4) ◽  
pp. 413-433 ◽  
Author(s):  
Luca Di Corato ◽  
Michele Moretto ◽  
Sergio Vergalli
Keyword(s):  
High Speed ◽  
Forest Conservation ◽  
Average Rate ◽  
Land Development ◽  
Brazilian Amazon ◽  
Forest Conversion ◽  
Conservation Policies ◽  
Expected Time ◽  
Long Run ◽  
The Impact

AbstractDeforestation results from the trade-off between benefits from forest conservation and economic profits associated with land development. However, as net gains are often uncertain, irreversible land development may later be regretted. To better inform conservation policies, we use a real options framework to model irreversible forest conversion under uncertain conservation benefits and determine the associated optimal long-run average rate of deforestation. We then analyze the impact of the demand for agricultural products on the rate of deforestation in the Brazilian Amazon. In a scenario analysis for the nine states of the Brazilian Amazon, we calculate: (i) the expected time for exhaustion of the current forest stock; and (ii) the potential forest coverage for the next 20, 100 and 200 years. Our results suggest that if forest benefits grow over time at a sufficiently high speed, they may significantly slow down deforestation. In contrast, the higher their volatility, the faster deforestation proceeds.

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