The SARS-CoV-2 pandemic is ongoing worldwide, causing prolonged pressure on molecular diagnostics. Viral antigen (Ag) assays have several advantages, ranging from lower cost to shorter turnaround time to detection. Given the rare occurrence of low-load viremia, antigen assays for SARSCoV-2 have focused on nasopharyngeal swab and saliva as biological matrices, but their effectiveness must be validated.
View Article and Find Full Text PDFWe report here an imported case of SARS-CoV-2 variant of concern B.1.1.
View Article and Find Full Text PDFWe report an imported case of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant P.1 detected in an asymptomatic traveler who arrived in Italy on an indirect flight from Brazil. This case shows the risk for introduction of SARS-CoV-2 variants from indirect flights and the need for continued SARS-CoV-2 surveillance.
View Article and Find Full Text PDFConsidering the ability of atmospheric-pressure cold plasma (ACP) to disrupt the biofilm matrix and rupture cell structure, it can be an efficient tool against virulent oral biofilms. However, it is fundamental that ACP does not cause damage to oral tissue. So, this study evaluated (1) the antimicrobial effect of ACP on single- and dual-species biofilms of Candida albicans and Staphylococcus aureus as well as (2) the biological safety of ACP on in vitro reconstituted oral epithelium.
View Article and Find Full Text PDFTreg cells are crucial to prevent immune dysregulation, but little is known about the frequency of these cells in neonates, particularly in very/moderate and late preterm newborns studied as separate groups. The CD4(+) CD25(hi) CD127(lo) FOXP3(+) Treg population was phenotypically characterized to assess maturation markers and gut-homing integrins by flow cytometry in the cord blood of healthy preterm newborns born at 30-33(6/7) gestation weeks (Group 1), at 34-36(6/7) gestation weeks (Group 2) and term newborns born at 37-41 gestation weeks (Group 3), compared to healthy adults. An inverse correlation of the Treg percentage and gestational age was found, with significantly higher frequencies in Group 1 compared to Groups 2 and 3 and in Group 2 compared to Group 3, and significantly higher Treg frequencies and numbers in the neonates compared to the adults.
View Article and Find Full Text PDFPolymicrobial biofilms are an understudied and a clinically relevant problem. This study evaluates the interaction between C. albicans, and methicillin- susceptible (MSSA) and resistant (MRSA) S.
View Article and Find Full Text PDFClin Implant Dent Relat Res
August 2016
Purpose: To evaluate in vitro, the efficacy of gutta-percha (GP) and polytetrafluoroethylene (PTFE) tape to act as a seal against the penetration of Escherichia coli through prosthetic implant abutments (PIA) with external hexagon (EH) and morse taper (MT) connections.
Materials And Methods: 120 sets of implant analogs with their respective PIA were used. 60 sets from each system were divided into four groups (n = 15): I - GP sealing; II - PTFE tape sealing; III - no sealing (NS) and IV - negative control.
Oral Surg Oral Med Oral Pathol Oral Radiol
July 2014
Objective: To evaluate the expression of phospholipase (PL) and secreted aspartyl proteinase (SAP) by Candida glabrata and C tropicalis obtained from the denture biofilms of healthy participants (16 isolates), patients with oral candidiasis with diabetes (10 isolates), and patients with oral candidiasis without diabetes (25 isolates).
Study Design: After incubation, the supernatants and pellets of the isolates were used for the enzymatic assays and quantification of colony-forming units (CFU), respectively. Colorimetric tests were used with phosphatidylcholine as a substrate for PL and azocasein as a substrate for SAP, and the absorbances of the samples were measured.
B+NK+SCID (severe combined immunodeficiency) due to IL7Rα deficiency represents approximately 10% of American SCID cases. To better understand the spectrum of autoimmune disorders associated with IL7Rα deficiency, we describe two unrelated IL7Rα-deficient female SCID infants whose clinical picture was dominated by autoimmune manifestations: one with intrauterine Omenn syndrome (OS) and another with persistent thrombocytopenic purpura since 4months of age. The OS baby harbored a homozygous p.
View Article and Find Full Text PDFThe secretion of hydrolytic enzymes is a fundamental virulence factor of Candida albicans to develop disease. The objective of this study was to characterise the virulence of 148 clinical isolates of C. albicans from oral candidiasis by assessing the expression of phospholipase (PL) and secreted aspartyl proteinase (SAP).
View Article and Find Full Text PDFPlasmodium chabaudi infection induces a rapid and intense splenic CD4(+) T cell response that contributes to both disease pathogenesis and the control of acute parasitemia. The subsequent development of clinical immunity to disease occurs concomitantly with the persistence of low levels of chronic parasitemia. The suppressive activity of regulatory T (T(reg)) cells has been implicated in both development of clinical immunity and parasite persistence.
View Article and Find Full Text PDFPlacental transfer of maternal IgG antibodies to the fetus is an important mechanism that provides protection to the infant while his/her humoral response is inefficient. IgG is the only antibody class that significantly crosses the human placenta. This crossing is mediated by FcRn expressed on syncytiotrophoblast cells.
View Article and Find Full Text PDFWe developed and optimized a simple, efficient and inexpensive method for in vitro culture of peripheral blood lymphocytes from the Brazilian tortoise Chelonoidis carbonaria (Testudinidae), testing various parameters, including culture medium, mitogen concentration, mitotic index, culture volume, incubation time, and mitotic arrest. Peripheral blood samples were obtained from the costal vein of four couples. The conditions that gave a good mitotic index were lymphocytes cultured at 37°C in minimum essential medium (7.
View Article and Find Full Text PDFThe pivotal role of spleen CD4(+) T cells in the development of both malaria pathogenesis and protective immunity makes necessary a profound comprehension of the mechanisms involved in their activation and regulation during Plasmodium infection. Herein, we examined in detail the behaviour of non-conventional and conventional splenic CD4(+) T cells during P. chabaudi malaria.
View Article and Find Full Text PDFMicron
December 2010
Complete blood counts and hemoglobin isoform data were gathered from 36 specimens of the turtle species Phrynops geoffroanus from the northwestern region of São Paulo State, Brazil. They were collected in an urban area. The hemoglobin profiles were obtained after red blood cell lysis and by electrophoretic migration in alkaline pH, acid pH, and neutral pH buffer.
View Article and Find Full Text PDFJ Interferon Cytokine Res
June 2010
The NK1.1 molecule participates in NK, NKT, and T-cell activation, contributing to IFN-gamma production and cytotoxicity. To characterize the early immune response to Plasmodium chabaudi AS, spleen NK1.
View Article and Find Full Text PDFJ Immunol
December 2008
The mechanisms responsible for the generation and maintenance of immunological memory to Plasmodium are poorly understood and the reasons why protective immunity in humans is so difficult to achieve and rapidly lost remain a matter for debate. A possible explanation for the difficulty in building up an efficient immune response against this parasite is the massive T cell apoptosis resulting from exposure to high-dose parasite Ag. To determine the immunological mechanisms required for long-term protection against P.
View Article and Find Full Text PDFThe drug discovery process is a starving machine requiring constant feeding with new chemical compounds. Synthetic or natural scaffolds: what are the best sources? While synthetic molecules are rapidly generated by combinatorial chemistry, they show lower chemical diversity than their natural counterparts. A significant fraction of known natural products is issued from microbial secondary metabolism; however, more than 95% of bacterial organisms remain unexploited as a source of active chemical compounds due to their cultivation difficulties.
View Article and Find Full Text PDFThis study evaluated the effectiveness of two microabrasion products for the removal of enamel fluorosis stains. Using a split-mouth study design, two operators used PREMA (PM) and Opalustre (OP) to remove fluorosis-like stains from 36 subjects (10-12 years old). Both products were rubbed onto the surface of the affected teeth for 30 seconds.
View Article and Find Full Text PDFStudies of the hemoglobin pattern in Brazilian reptiles are important for determining ecological and phylogenetic relationships, but they are scarce. Peripheral blood samples were obtained from 7 males and 18 females of Rhinoclemmys punctularia. The hematological profile was based on the total hemoglobin and hematocrit values.
View Article and Find Full Text PDFPolyclonal B-cell activation is a feature of the early spleen cell response to blood-stage Plasmodium chabaudi malaria. Immunity to blood-stage malaria is guaranteed by the generation of B cells able to produce parasite-specific antibodies mainly from the immunoglobulin (Ig)G2a isotype. In the present study, we characterized the spleen B-cell compartment during blood-stage P.
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