Publications by authors named "Karina Castro"

The ANESPSAT, a synthetic spilanthol derivative, and its nanoformulation were evaluated against Rhipicephalus microplus and Amblyomma sculptum ticks. ANESPSAT activity was compared with spilanthol and derivatives (ANESPE and others). The compound was synthesized in a gram-scale by a 2-step process, comprising a direct ester amidation and a Horner-Wadsworth- Emmons reaction.

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There is an increasing interest in essential oils extracted from Verbenaceae plant species as potential sources of biologically active compounds that could provide a starting point for designing novel phyto-pharmaceuticals in aquaculture. The present study was aimed to investigate the chemical composition, antioxidant activity, acute toxicity and antimicrobial effects against Vibrio parahaemolyticus of essential oils extracted from Lippia alba and L. origanoides.

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Article Synopsis
  • The study evaluated the chemical makeup and acaricide properties of essential oils from Egletes viscosa and Lippia schaueriana on female Rhipicephalus sanguineus ticks.
  • Chemical analysis revealed E. viscosa essential oil contained 27 components, while L. schaueriana had 18, both affecting over 98% of their chemical profiles.
  • Exposure to the essential oils significantly decreased egg production and viability in ticks, causing notable morphological changes in the eggs, with E. viscosa being more effective than L. schaueriana at various concentrations.
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Autonomous replication and segregation of mitochondrial DNA (mtDNA) creates the potential for evolutionary conflict driven by emergence of haplotypes under positive selection for 'selfish' traits, such as replicative advantage. However, few cases of this phenomenon arising within natural populations have been described. Here, we survey the frequency of mtDNA horizontal transfer within the canine transmissible venereal tumour (CTVT), a contagious cancer clone that occasionally acquires mtDNA from its hosts.

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  • Canine transmissible venereal tumor (CTVT) is a unique cancer that has survived for thousands of years by spreading through cell transfer from one dog to another.
  • Researchers analyzed 546 CTVT exomes to create a timeline and track its global spread, discovering a specific mutational process that occurred early in its evolution but later disappeared.
  • The study found that while CTVT shows minimal ongoing positive selection and some negative selection in key genes, random genetic drift plays a major role in the long-term evolution of this cancer.
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Objective: to evaluate the benefits and disadvantages of the ventral decubitus position compared with that of Lloyd-Davies in patients submitted to abdominoperineal amputation of the rectum.

Methods: we conducted a retrospective study of 56 patients submitted to abdominoperineal amputation of the rectum due to distal rectal and anal canal neoplasms, treated at the Central Hospital of the Santa Casa de Misericórdia in São Paulo between 2008 and 2017.

Results: patients' mean age was 63.

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  • The study examined how different concentrations of Acmella oleracea's ethanolic extract (EEAO) affected the development of germ cells in semi-engorged female Amblyomma cajennense ticks.
  • A total of 100 ticks were tested in five groups, including various controls and treatment groups with differing EEAO concentrations, using an immersion method to administer the extract.
  • The results showed that EEAO significantly disrupted oocyte development, causing cell shape changes, disorganization, and a decrease in important cell components, highlighting its potential as a natural strategy to control these tick ectoparasites.
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The aim of this study was to evaluate the acaricidal activity of essential oils from three species of plants with intermediary concentrations of 1,8-cineole against the tick species Rhipicephalus (Boophilus) microplus. For this purpose, five serial concentrations (100.0, 50.

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This study aimed to determine the dynamics of natural infection in the transmission of Babesia spp. to cattle in an enzootic instability area in Northeastern Brazil. Blood samples were collected from 30 calves located on two dairy farms to determine the packed cell volume (PCV) and the timing of the primo-infection using polymerase chain reaction (PCR) and their association with climatic factors and management practices.

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The canine transmissible venereal tumor (CTVT) is a clonally transmissible cancer that regresses spontaneously or after treatment with vincristine, but we know little about the regression mechanisms. We performed global transcriptional, methylation, and functional pathway analyses on serial biopsies of vincristine-treated CTVTs and found that regression occurs in sequential steps; activation of the innate immune system and host epithelial tissue remodeling followed by immune infiltration of the tumor, arrest in the cell cycle, and repair of tissue damage. We identified CCL5 as a possible driver of CTVT regression.

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  • * Male ticks were divided into groups and exposed to different treatments, with histological analysis conducted after dissection to evaluate changes in their reproductive systems.
  • * Results showed that higher concentrations of the extract caused significant alterations in secretory cell functions and reduced key components necessary for sperm viability, demonstrating its cytotoxic potential in a dose-dependent manner.
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Ecuador is undergoing a process of clinical research development and strengthening. At the turn of the century, Ecuador experienced a favorable transition period of economic stability, which enabled advances in the health system and improvements in population welfare indicators. During this period, Ecuador created an institutional infrastructure to support the implementation and development of research projects.

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The use of synthetic acaricides is currently the main method to control ticks. However, the indiscriminate use of these chemicals can lead to the selection of resistant individuals and in the accumulation of chemical residues in the environment, contaminating the soil and water streams, consequently affecting the flora, fauna, and the human beings as well. In this sense, the objective of this study was to investigate the acaricidal effect of crude ethanolic extract of Acmella oleracea (L.

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The aim of this study was to assess the activity of aqueous (AE) and ethanolic extracts (EE) and pilocarpine hydrochloride, which were extracted and isolated from Pilocarpus microphyllus (Jaborandi), respectively, on Rhipicephalus (Boophilus) microplus. High performance liquid chromatography (HPLC) was performed to quantify these compounds. Larval packet and adult immersion tests were conducted with different concentrations.

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Article Synopsis
  • Canine transmissible venereal tumor (CTVT) is a unique form of cancer in dogs, dating back around 11,000 years and affecting dogs worldwide.
  • Researchers analyzed 449 complete mitochondrial DNA sequences from CTVT cases and found that mitochondrial DNA has been transferred between different hosts at least five times, creating distinct tumor groups that align with historical dog migrations.
  • The study suggests that this captured mitochondrial DNA helps drive the spread of CTVT globally and emphasizes the critical role of mitochondrial DNA in the evolution of cancer.
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Unlabelled: Pharyngotonsillitis by β-hemolytic Streptococcus mostly affects children and immunocompromised, being Streptococcus pyogenes (Group A) the most common agent in bacterial pharyngotonsillitis.

Aim: This work targeted the research of β-hemolytic Streptococcus Group-A (SBHGA) and No-A (SBHGNA) in the oropharynx of individuals with special health needs from the APAE (Maceió-AL).

Method: A prospective study with oropharynx samples from patients with Down syndrome and other mental disorders (test) and students from a private school (control) aged 5-15 years.

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We have previously shown that high density lipoprotein is the most abundant protein in the carp plasma and displays bactericidal activity in vitro. Therefore the aim of this study was to analyze the contribution of its principal apolipoproteins, apoA-I and apoA-II, in defense. Both apolipoproteins were isolated by a two step procedure involving affinity and gel filtration chromatography and were shown to display bactericidal and/or bacteriostatic activity in the micromolar range against Gram-positive and Gram-negative bacteria, including some fish pathogens.

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