10 research outputs found

    Effect of simulated pulpal pressure on composite bond strength to dentin prepared using Er, Cr: YSGG laser

    Get PDF
    Bonding to dentin with adhesive systems is affected by the tubular fluid flow induced by pulpal pressure. The aim of this study was to evaluate the effect of simulated pulpal pressure on the microtensile bond strength of an adhesive to dentin surface prepared by laser irradiation. Crowns oftwenty human extracted third molars were subjected to Er, Cr: YSGG laser beams. Specimens were divided into two groups according to pulpal pressure simulation. In the first group resin composite (Z-250 Filtek) was bonded to flat surfaces of samples using dentin bonding agent (Single Bond) under simulated pulpal pressure. In the second group, the same procedure was carried out without pulpal pressure simulation. After storing the teeth in saline solution at 37°C for 24 h, thirty 1-mm-thick sliceswere cut from the samples in each group and subjected to bond strength test. Microtensile bond strength was determined using a universal testing machine at a crosshead speed of 2 mm/min. Statistical significance was determined by T-test (p < 0.05). There was a statistically significantdifference in the mean microtensile bond strengths between the groups (p < 0.0005). Simulated pulpal pressure had a negative effect on microtensile bond strength of laser ablated dentin when Single Bondadhesive system was used

    Development of an integrase-based ELISA for specific diagnosis of individuals infected with HIV

    No full text
    Currently, enzyme immunoassays (EIAs) are the most common immunological diagnostic methods that are used as the screening tool in HIV detection. Among all three major genes of HIV, the products of gag and env are usually used in EIAs (ELISAs and rapid tests). Hence, the presence of cross reacting antibodies against these antigens leads to the appearance of repetitive false positive results in screening tests. Re-testing the primary reactive samples with EIAs using other HIV antigens can considerably reduce the rate of false positive results. The products of pol gene may act as an appropriate candidate in this context. Integrase is a conserved and immunogenic product of HIV, encoded by the pol gene. The aim of this research was to determine the sensitivity and specificity of an ELISA detecting integrase antibodies. Recombinant integrase was produced in Escherichia coli to develop the integrase-based ELISA. Assay performance was evaluated by HIV positive and negative sera and an HIV panel of BBI (PRB-601). The sensitivity and specificity of assay was determined as 96.7 95% confidence interval: 91.3-98.9% and 100% 95% CI: 96.1-100%, respectively. High specificity of this assay may suggest its possible use in the detection of HIV. © 2015 Elsevier B.V

    High avidity anti-integrase antibodies discriminate recent and non-recent HIV infection: Implications for HIV incidence assay

    No full text
    Estimation of HIV incidence provides real-time information of HIV transmission trends for decision makers. Anti-integrase antibodies are the last ones produced during seroconversion and presence of high-avidity anti-integrase antibodies indicates the chronicity of HIV infection. This study aimed to evaluate the performance of these antibodies in discriminating of recent from non-recent HIV infection. For this purpose, different ELISA formats were developed to detect high-avidity anti-integrase antibodies in a commercially available performance panel, and the best assay was selected for further evaluation. The false recent rate of the selected assay was evaluated in a panel of Iranian patients and compared to two commercial assays, BED-EIA and LAg-Avidity. While the false recent rate of the developed assay was 3.8, it was 14.1 and 1.3 for BED-EIA and LAg-Avidity, respectively. To our knowledge, this is the first report to study the performance of high-avidity anti-integrase antibodies for classification of HIV infection. The preliminary results showed that the specificity of the newly developed assay is markedly higher than BED-EIA and is comparable with LAg-Avidity. The promising results point to the potential use of anti-integrase antibodies as a biomarker in HIV incidence laboratory tests or algorithms. The developed assay needs further evaluation in future. © 201

    Designing and constructing an 100 bp DNA Ladder by combining PCR and enzyme digestion methods

    No full text
    &quot;n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Molecular DNA markers are one of the most important tools in molecular biology labs. The size of DNA molecules is determined by comparing them with known bands of markers during gel electrophoresis. There are many different protocols to produce these kinds of molecular markers. In this study we have suggested an efficient strategy to produce molecular weight markers in industrial proportions.&quot;n&quot;nMethods : To achieve the desired sizes of DNA fragments, a combination of two previously known methods, restriction enzyme digestion and polymerase chain reaction (PCR), were used. The enzymatic digestion process was based on designing and constructing plasmids which equaled in size with the desired length of DNA fragments and produced the desired DNA fragment upon linearization. In the PCR method, the desired length of DNA fragments were cloned in multiple cloning sites of pTZ57R plasmid and in a PCR reaction, the new constructed plasmid was used as a template to produce the final fragment.&quot;n&quot;nResults : Upon application of this strategy, 2000 and 3000 bp DNA fragments were produced by enzymatic digestion of plasmids of the same size. Moreover, 100 to 1500 bp fragments were produced during PCR using only a set of forward and reverse primers at the flanking region of pTZ57R multiple cloning site.&quot;n&quot;nConclusion: The highest advantage of this cost-benefit approach is to produce different types of molecular weight markers by using an effective and short protocol.&quot;n&quot;nKeywords: DNA markers, DNA Ladder, agarose gel electrophoresis, molecular weight

    High avidity anti-integrase antibodies discriminate recent and non-recent HIV infection: Implications for HIV incidence assay

    No full text
    Estimation of HIV incidence provides real-time information of HIV transmission trends for decision makers. Anti-integrase antibodies are the last ones produced during seroconversion and presence of high-avidity anti-integrase antibodies indicates the chronicity of HIV infection. This study aimed to evaluate the performance of these antibodies in discriminating of recent from non-recent HIV infection. For this purpose, different ELISA formats were developed to detect high-avidity anti-integrase antibodies in a commercially available performance panel, and the best assay was selected for further evaluation. The false recent rate of the selected assay was evaluated in a panel of Iranian patients and compared to two commercial assays, BED-EIA and LAg-Avidity. While the false recent rate of the developed assay was 3.8, it was 14.1 and 1.3 for BED-EIA and LAg-Avidity, respectively. To our knowledge, this is the first report to study the performance of high-avidity anti-integrase antibodies for classification of HIV infection. The preliminary results showed that the specificity of the newly developed assay is markedly higher than BED-EIA and is comparable with LAg-Avidity. The promising results point to the potential use of anti-integrase antibodies as a biomarker in HIV incidence laboratory tests or algorithms. The developed assay needs further evaluation in future. © 201

    Maternal transfer of IgA and IgG SARS-CoV-2 specific antibodies transplacentally and via breast milk feeding.

    No full text
    BackgroundAlthough there have been many studies on antibody responses to SARS-CoV-2 in breast milk, very few have looked at the fate of these in the infant, and whether they are delivered to immunologically relevant sites in infants.MethodsMother/infant pairs (mothers who breast milk fed and who were SARS-CoV-2 vaccinated before or after delivery) were recruited for this cross-sectional study. Mother blood, mother breast milk, infant blood, infant nasal specimen, and infant stool was tested for IgA and IgG antibodies against SARS-CoV-2 spike trimer.ResultsThirty-one mother/infant pairs were recruited. Breast milk fed infants acquired systemic anti-spike IgG antibodies only if their mothers were vaccinated antepartum (100% Antepartum; 0% Postpartum; PConclusionVaccination antepartum followed by breast milk feeding appears to be the best way to provide systemic and local anti-SARS-CoV-2 antibodies for infants. The presence of high titer SARS-CoV-2-specific IgA in the nose of infants points to the potential importance of breast milk feeding early in life for maternal transfer of mucosal IgA antibodies. Expectant mothers should consider becoming vaccinated antepartum and consider breast milk feeding for optimal transfer of systemic and mucosal antibodies to their infants

    Maternal transfer of IgA and IgG SARS-CoV-2 specific antibodies transplacentally and via breast milk feeding

    No full text
    Background Although there have been many studies on antibody responses to SARS-CoV-2 in breast milk, very few have looked at the fate of these in the infant, and whether they are delivered to immunologically relevant sites in infants. Methods Mother/infant pairs (mothers who breast milk fed and who were SARS-CoV-2 vaccinated before or after delivery) were recruited for this cross-sectional study. Mother blood, mother breast milk, infant blood, infant nasal specimen, and infant stool was tested for IgA and IgG antibodies against SARS-CoV-2 spike trimer. Results Thirty-one mother/infant pairs were recruited. Breast milk fed infants acquired systemic anti-spike IgG antibodies only if their mothers were vaccinated antepartum (100% Antepartum; 0% Postpartum; PConclusion Vaccination antepartum followed by breast milk feeding appears to be the best way to provide systemic and local anti-SARS-CoV-2 antibodies for infants. The presence of high titer SARS-CoV-2-specific IgA in the nose of infants points to the potential importance of breast milk feeding early in life for maternal transfer of mucosal IgA antibodies. Expectant mothers should consider becoming vaccinated antepartum and consider breast milk feeding for optimal transfer of systemic and mucosal antibodies to their infants
    corecore