Publications by authors named "Alvarenga D"

Background: Oral squamous cell carcinoma (OSCC) is an aggressive cancer, with prognosis influenced by clinical variables as well grading systems and perineural invasion (PNI), which are associated to poorer outcomes, including higher rates of recurrence and metastasis. This study aims to evaluate OSCC using three grading systems and assess the impact of PNI and clinicopathologic parameters on patient survival.

Material And Methods: Eighty-one primary OSCC samples were analyzed.

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Unlabelled: Nitrogen (N) fixation in association with mosses could be a key source of new N in tropical montane cloud forests since these forests maintain high humidity levels and stable temperatures, both of which are important to N fixation. Here, nutrient availability could be a prominent control of N fixation processes. However, the mechanisms and extent of these controls, particularly in forests at different successional stages, remains unknown to date.

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Article Synopsis
  • Tropical montane cloud forests are unique high-altitude ecosystems with high humidity, supporting organisms like bryophytes that depend on moisture.
  • This study measured nitrogen fixation rates linked to bryophytes on pumpwood trees and in nearby soil and litter in both primary and secondary cloud forests in Costa Rica.
  • Results showed that nitrogen fixation was much higher in the secondary forest, with epiphytic bryophytes fixing nitrogen at 57 times the rate found in litter and 270 times that of the soil, indicating light intensity is a key factor in this process.
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Moss-cyanobacteria symbioses were proposed to be based on nutrient exchange, with hosts providing C and S while bacteria provide N, but we still lack understanding of the underlying molecular mechanisms of their interactions. We investigated how contact between the ubiquitous moss Hylocomium splendens and its cyanobiont affects nutrient-related gene expression of both partners. We isolated a cyanobacterium from H.

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Introduction: Zoonotic transmission is a challenge for the control and elimination of malaria. It has been recorded in the Atlantic Forest, outside the Amazon which is the endemic region in Brazil. However, only very few studies have assessed the antibody response, especially of IgM antibodies, in Neotropical primates (NP).

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Article Synopsis
  • The study focuses on Plasmodium simium, a malaria-causing parasite in Brazilian non-human primates (NHP), which poses a risk for human infections and challenges malaria elimination efforts.* -
  • Researchers analyzed blood samples from 35 NHP using quantitative PCR to measure specific parasite transcript levels, finding that 87.5% of samples confirmed P. simium infection with various rates of gametocyte presence.* -
  • This research establishes a molecular understanding of P. simium in NHP, highlighting low gametocyte counts in most carriers and the potential implications for malaria transmission dynamics.*
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  • Current malaria elimination strategies overlook the role of non-human primates (NHPs) in spreading Plasmodium vivax, which is less responsive to control methods.* -
  • Blood samples from free-living and captive Neotropical monkeys revealed a 4.4% infection rate of P. vivax, indicating that these animals can harbor the pathogen.* -
  • The findings highlight the need to understand how NHP infections could sustain malaria transmission in humans, suggesting that wildlife management should be included in malaria elimination plans.*
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Cyanobacteria associated with mosses play a key role in the nitrogen (N) cycle in unpolluted ecosystems. Mosses have been found to release molecules that induce morphophysiological changes in epiphytic cyanobionts. Nevertheless, the extent of moss influence on these microorganisms remains unknown.

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Mosses are non-vascular plants usually found in moist and shaded areas, with great ecological importance in several ecosystems. This is especially true in northern latitudes, where mosses are responsible for up to 100% of primary production in some ecosystems. Mosses establish symbiotic associations with unique bacteria that play key roles in the carbon and nitrogen cycles.

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Malaria is an acute febrile disease caused by a protozoan of the genus . Light microscopy (LM) is the gold standard for the diagnosis of malaria. Despite this method being rapid and inexpensive, it has a low limit of detection, which hampers the identification of low parasitemia infections.

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Harmful cyanobacterial blooms (cyanoHABs) cause recurrent toxic events in global watersheds. Although public health agencies monitor the causal toxins of most cyanoHABs and scientists in the field continue developing precise detection and prediction tools, the potent anticholinesterase neurotoxin, guanitoxin, is not presently environmentally monitored. This is largely due to its incompatibility with widely employed analytical methods and instability in the environment, despite guanitoxin being among the most lethal cyanotoxins.

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Microbial natural products are compounds with unique chemical structures and diverse biological activities. Cyanobacteria commonly possess a wide range of biosynthetic gene clusters (BGCs) to produce natural products. Although natural product BGCs have been found in almost all cyanobacterial genomes, little attention has been given in cyanobacterial research to the partitioning of these biosynthetic pathways in chromosomes and plasmids.

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  • Serine proteases are crucial in various physiological processes and cancer progression, and aeruginosins, natural products from cyanobacteria, can inhibit these enzymes effectively.
  • Researchers sequenced the genome of UHCC 0038, discovering a gene cluster related to suomilide, a member of the aeruginosin family, revealing its strong inhibition of human trypsin enzymes with low effective concentrations.
  • Suomilide inhibited the invasion of metastatic prostate cancer cells without affecting overall cell growth, highlighting its potential as a targeted cancer treatment, particularly for cancers overexpressing trypsin-3.
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Background: Plasmodium simium, a malaria parasite of non-human primates (NHP), was recently shown to cause zoonotic infections in humans in Brazil. We sequenced the P. simium genome to investigate its evolutionary history and to identify any genetic adaptions that may underlie the ability of this parasite to switch between host species.

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We describe here the structure and organization of TnCentral (https://tncentral.proteininformationresource.org/ [or the mirror link at https://tncentral.

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Mosses can be responsible for up to 100% of net primary production in arctic and subarctic tundra, and their associations with diazotrophic cyanobacteria have an important role in increasing nitrogen (N) availability in these pristine ecosystems. Predictions about the consequences of climate change in subarctic environments point to increased N mineralization in soil and higher litter deposition due to warming. It is not clear yet how these indirect climate change effects impact moss-cyanobacteria associations and N fixation.

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Lipopeptides are important secondary metabolites produced by microbes. They find applications in environmental decontamination and in the chemical, pharmaceutical and food industries. However, their production is expensive.

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Second-generation biofuel production is in high demand, but lignocellulosic biomass' complexity impairs its use due to the vast diversity of enzymes necessary to execute the complete saccharification. In nature, lignocellulose can be rapidly deconstructed due to the division of biochemical labor effectuated in bacterial communities. Here, we analyzed the lignocellulolytic potential of a bacterial consortium obtained from soil and dry straw leftover from a sugarcane milling plant.

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Human malaria due to zoonotic transmission has been recorded in the Atlantic Forest, an extra-Amazonian area in Brazil, which are a challenge for malaria control. Naturally acquired humoral immune response against pre-erythrocytic and erythrocytic antigens of Neotropical primates (NP) was evaluated here to improve the knowledge about the exposure of those animals to the malaria transmission and support the identification of the potential reservoirs of the disease in the Atlantic Forest. Blood samples of 154 monkeys from three areas of the Atlantic Forest were used to identify IgG antibodies against peptides of the repeat region of the major pre-erythrocytic antigen, the circumsporozoite protein (CSP), of (PvCSP), (Pb/PmCSP), and (PfCSP) by ELISA.

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The cyanobacterial genus is an important contributor to carbon and nitrogen bioavailability in terrestrial ecosystems and a frequent partner in symbiotic relationships with non-diazotrophic organisms. However, since this currently is a polyphyletic genus, the diversity of -like cyanobacteria is considerably underestimated at this moment. While reviewing the phylogenetic placement of previously isolated -like cyanobacteria originating from Brazilian Amazon, Caatinga and Atlantic forest samples, we detected 17 strains isolated from soil, freshwater, rock and tree surfaces presenting patterns that diverged significantly from related strains when ecological, morphological, molecular and genomic traits were also considered.

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We report here a series of glucosides which are active as inhibitors of the angiotensin converting enzyme (ACE). They are structurally related to the natural compound eugenol and exhibited significant inhibition values. Their syntheses were expeditious and we could obtain informative docking plots of them complexed to this enzyme.

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Background & Aims: The precise determination of non-alcoholic fatty liver disease (NAFLD) onset is challenging. Thus, the initial hepatic responses to fat accumulation, which may be fundamental to our understanding of NAFLD evolution and clinical outcomes, are largely unknown. Herein, we chronologically mapped the immunologic and metabolic changes in the liver during the early stages of fatty liver disease in mice and compared this with human NAFLD samples.

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Background: is a cyanobacterial genus found on the surface of mineral substrates and plants such as bromeliads, orchids and eucalyptus. stands out among cyanobacteria due to causing damage to the leaves of its host in an interaction not yet observed in other cyanobacteria. Previous studies revealed that UFV-E1 is capable of leading eucalyptus leaves to suffer internal tissue damage and necrosis by unknown mechanisms.

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Neutrophils were classically described as powerful effectors of acute inflammation, and their main purpose was assumed to be restricted to pathogen killing through production of oxidants. As consequence, neutrophils also may lead to significant collateral damage to the healthy tissues, and after performing these tasks, these leukocytes are supposed to die within tissues. However, there is a growing body of evidence showing that neutrophils also play a pivotal role in the resolution phases of inflammation, because they can modulate tissue environment due to secretion of different kind of cytokines.

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Several species of rapidly growing mycobacteria (RGM) have been associated with biofilms in areas such as biomedical devices, water distribution systems, cosmetic surgery, and catheter-related blood infections. Biofilms which exhibit antimicrobial resistance such as those formed by the genus Mycobacterium pose a significant risk to health and are of particular interest to researchers. Licarin A (a neolignan found in numerous plant species e.

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