Publications by authors named "Samuel R Santos"

Article Synopsis
  • A fungus classified as a critically important pathogen by the WHO poses a serious threat to immunocompromised individuals, motivating research on potential vaccines.
  • The study focuses on two semi-synthetic glycoconjugate vaccines that target a specific capsular polysaccharide (GXM) common in most cryptococcosis cases, created by conjugating a synthetic decasaccharide antigen to two different proteins.
  • Immunization in mice showed promising results with one glycoconjugate leading to increased survival rates and specific antibody responses, although more optimization is needed for it to become part of a broader vaccine strategy.
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Background: The treatment of acute ischemic stroke with cerebral reperfusion therapy requires rapid care and recognition of symptoms.

Objective: To analyze the effectiveness of implementing protocols for acute ischemic stroke in reducing care time.

Methods: Systematic review, which was performed with primary studies in Portuguese, English, and Spanish published between 2011 and 2020.

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Cryptococcosis is a devastating fungal disease associated with high morbidity and mortality even when treated with antifungal drugs. Bionized nanoferrite (BNF) nanoparticles are powerful immunomodulators, but their efficacy for infectious diseases has not been investigated. Administration of BNF nanoparticles to mice with experimental cryptococcal pneumonia altered the outcome of infection in a dose response manner as measured by CFU and survival.

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Amoeboid predators, such as amoebae, are proposed to select for survival traits in soil microbes such as ; these traits can also function in animal virulence by defeating phagocytic immune cells, such as macrophages. Consistent with this notion, incubation of various fungal species with amoebae enhanced their virulence, but the mechanisms involved are unknown. In this study, we exposed three strains of (1 clinical and 2 environmental) to predation by for prolonged times and then analyzed surviving colonies phenotypically and genetically.

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Treatment modalities for systemic mycoses are still limited. Currently, the main antifungal therapeutics include polyenes, azoles, and echinocandins. However, even in the setting of appropriate administration of antifungals, mortality rates remain unacceptably high.

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Several series of tests have shown that fresh, intact samples of Giardia duodenalis and Cryptosporidium parvum (oo)cysts are not marked by fluorescent probes such as carboxyfluorcein-succinimidyl-diacetate-ester (CFDA-SE), C12-resazurin and SYTOX® Green, probably because of their robust cell walls. These dyes fail to indicate the viability of such protozoa and allow negative responses to be recorded from living and infectious samples. Cryptosporidium parvum showed stronger isolation from chemicals, with living oocysts remaining unstained by the probe for up to 90 days after extraction.

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Measurements of spontaneous ultra-weak light (biophoton) emission from native Brazilian and German wheat seedlings in three simultaneous series of germination tests are presented, two run in Germany and one in Brazil. Seedlings in both countries presented semi-circadian rhythms of emission that were in accordance with the local lunisolar gravimetric tidal acceleration, as did seeds which had been transported from Brazil to Germany. The simultaneity of the photon emission patterns in all tests argues for the lunisolar tide and its rhythmic variations as regulators of the natural rhythm of photon emission.

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