Estimates of prevalence of HFE mutations are within the expected range for non-Hispanic whites and blacks but the estimated prevalence of the C282Y mutation among Mexican-Americans is less than expected. Mutation data now need to be linked to clinically relevant indices, such as transferrin saturation level.
The neutralization epitope(s) of the hepatitis E virus (HEV) was studied by an in vitro neutralization assay using antibodies obtained by immunization of mice with 51 overlapping 30-mer synthetic peptides spanning the region 221-660 amino acids (aa) of the HEV open reading frame 2 encoded protein (pORF2) and 31 overlapping recombinant proteins of different sizes derived from the entire pORF2 of the HEV Burma strain. Antibodies against synthetic peptides and short recombinant proteins of approximately 100 aa did not neutralize HEV, suggesting the HEV neutralization epitope(s) is conformation-dependent. However, one recombinant protein of approximately 400 aa in length comprising the pORF2 sequence at position 274-660 aa as well as all truncated derivatives of this protein containing region 452-617 aa elicited antibodies, demonstrating HEV neutralizing activity. These findings establish for the first time that the minimal size fragment, designated pB166, that can efficiently model the neutralization epitope(s) is 166 aa in length and is located at position 452-617 aa of the HEV pORF2. Additionally, antibodies against pB166 were found to cross-neutralize three different HEV genotypes, suggesting that a common neutralization epitope(s) may exist within the different HEV genotypes. Thus, recombinant proteins constructed in this study may be considered as potential candidates for the development of an HEV subunit vaccine as well as for the development of highly sensitive and specific diagnostic tests.
TT virus (TTV) is a recently discovered infectious agent originally obtained from transfusion-related hepatitis. However, the causative link between the TTV infection and liver disease remains uncertain. Recent studies demonstrated that genome sequences of different TTV strains are significantly divergent. To assess genetic heterogeneity of the TTV genome in more detail, a sequence analysis of PCR fragments (271 bp) amplified from open reading frame 1 (ORF1) was performed. PCR fragments were amplified from 5 to 40% of serum specimens obtained from patients with different forms of hepatitis who reside in different countries (e.g., China, Egypt, Vietnam, and the United States) and from normal human specimens obtained from U.S. residents. A total of 170 PCR fragments were sequenced and compared to sequences derived from the corresponding TTV genome region deposited in GenBank. Genotypes 2 and 3 were found to be significantly more genetically related than any other TTV genotype. Moreover, three sequences were shown to be almost equally related to both genotypes 2 and 3. These observations suggest a merger of genotypes 2 and 3 into one genotype, 2/3. Additionally, five new groups of TTV sequences were identified. One group represents a new genotype, whereas the other four groups were shown to be more evolutionary distant from all known TTV sequences. The evolutionary distances between these four groups were also shown to be greater than between TTV genotypes. The phylogenetic analysis suggested that these four new genetic groups represent closely related yet different viral species. Thus, TTV exists as a "swarm" of at least five closely related but different viruses. These observations suggest a high degree of genetic complexity within the TTV population. The finding of the additional TTV-related species should be taken into consideration when the association between TTV infections and human diseases of unknown etiology is studied.A new TT virus (TTV) was recently discovered in a serum specimen obtained from a Japanese patient with posttransfusion hepatitis of unknown etiology (16,20). In the same study, TTV DNA was detected by PCR in serum specimens from three of five patients with posttransfusion non-A through non-G hepatitis. It was shown that TTV DNA titers closely correlated with the level of aminotransferase in these three patients (16). Additionally, TTV DNA was found in liver tissues in titers that are equal to or 10 to 100 times greater than those in the corresponding serum specimens (20). In combination with these findings, the identification of TTV DNA in 47% of patients with fulminant hepatitis and 46% of patients with chronic liver disease of unknown etiology (20) was used to hypothesize that TTV may be responsible for at least a part of acute and chronic liver disease of unknown etiology (16,20). However, the detection of TTV DNA in 12% of normal blood donors in Japan (20) indicates that this hypothesis should be thoroughly tested before a final conclusion is drawn regarding an association between TTV a...
BackgroundRoutine HIV viral load testing is not widely accessible in most resource-limited settings, including Kenya. To increase access to viral load testing, alternative sample types like dried blood spots (DBS), which overcome the logistic barriers associated with plasma separation and cold chain shipment need to be considered and evaluated. The current study evaluated matched dried blood spots (DBS) and dried plasma spots (DPS) against plasma using the Abbott M 2000 (Abbott) and Roche Cobas Ampliprep/Cobas TaqMan (CAP/CTM) quantitative viral load assays in western Kenya.MethodsMatched plasma DBS and DPS were obtained from 200 HIV-1 infected antiretroviral treatment (ART)-experienced patients attending patient support centers in Western Kenya. Standard quantitative assay performance parameters with accompanying 95% confidence intervals (CI) were assessed at the assays lower detection limit (400cps/ml for CAP/CTM and 550cps/ml for Abbott) using SAS version 9.2. Receiver operating curves (ROC) were further used to assess viral-load thresholds with best assay performance (reference assay CAP/CTM plasma).ResultsUsing the Abbott test, the sensitivity and specificity, respectively, for DPS were (97.3%, [95%CI: 93.2–99.2] and 98.1% [95%CI: 89.7–100]) and those for DBS (93.9% [95%CI: 88.8–97.2] and 88.0% [95%CI: 82.2–92.4]). The correlation and agreement using paired plasma and DPS/DBS were strong, with r2 = 90.5 and rc = 68.1. The Bland-Altman relative percent change was 95.3 for DPS, (95%CI: 90.4–97.7) and 73.6 (95%CI: 51.6–86.5) for DBS. Using the CAP/CTM assay, the sensitivity for DBS was significantly higher compared to DPS (100.0% [95% CI: 97.6–100.0] vs. 94.7% [95%CI: 89.8–97.7]), while the specificity for DBS was lower: 4%, [95% CI: 0.4–13.7] compared to DPS: 94.0%, [95% CI: 83.5–98.7]. When compared under different clinical relevant thresholds, the accuracy for the Abbott assay was 95% at the 1000cps/ml cut-off with a sensitivity and specificity of 96.6% [95% CI 91.8–98.7] and 90.4% [95% CI 78.2–96.4] respectively. The optimum threshold was at 3000 cps/ml with an accuracy of 95.5%, sensitivity and specificity of 94.6% [95%CI 89.3–97.5] and 98.1% [95%CI 88.4–99.9]) respectively. The best threshold for CAP/CTM was at 4000 copies /mL, with 92.5% accuracy (sensitivity of 96.0% [95%CI 91.0–98.3] and specificity of 82.7% [95%CI 69.2–91.3]).ConclusionsThere was similar performance between matched DBS, DPS and plasma using the Abbott test, and good correlation for matched DPS and plasma using the CAPCTM test. The findings suggest that DBS and DPS may be reliably used as alternative specimens to plasma to measure HIV-1 VL using Abbott, and DPS may be reliably used with CAP/CTM in resource-limited settings.
The nephroblastoma overexpressed (NOV) gene, also called CCN3, regulates differentiation of skeletal mesenchymal cells. Bone morphogenetic proteins (BMPs) play important roles in osteoblast differentiation and bone formation, but the effects of CCN3 on BMP expression and bone formation in cultured osteoblasts are largely unknown. Here we found that CCN3 increased BMP-4 expression and bone nodule formation in cultured osteoblast. Monoclonal antibodies for α5β1 and αvβ5 integrins, and inhibitors of integrin-linked kinase (ILK), p38, and JNK, all inhibited CCN3-induced bone nodule formation and BMP-4 up-regulation of osteoblasts. CCN3 stimulation increased the kinase activity of ILK and phosphorylation of p38 and JNK. Inhibitors of activator protein-1 (AP-1) also suppressed bone nodule formation and BMP-4 expression enhanced by CCN3. Moreover, CCN3-induced c-Jun translocation into the nucleus, and the binding of c-Jun to the AP-1 element on the BMP-4 promoter were both inhibited by specific inhibitors of the ILK, p38, and JNK cascades. Taken together, our results provide evidence that CCN3 enhances BMP-4 expression and bone nodule formation in osteoblasts, and that the integrin receptor, ILK, p38, JNK, and AP-1 signaling pathways may be involved.
Programs focused on preventing vertical transmission need to increase their commitment to child-centric interventions and broaden their measure of success to reflect infants who test negative at the end of the exposure period. This paper argues that EID is a key strategy to retaining HIV-exposed infants through the end of the exposure period, as it provides an opportunity to offer early clinical care and continuous follow up. It is imperative that maternal and child survival programs become sensitized to the urgency of early identification of HIV in infants and their retention in care.
Bradykinin (BK) is an inflammatory mediator, and shows elevated levels in regions of severe injury and inflammatory diseases. BK has recently been shown to be involved in carcinogenesis and cancer progression. In this study, we found that BK increased the migration and the expression of alpha2beta1 integrin in human chondrosarcoma cells. We also found that human chondrosarcoma tissues had significantly higher expression of the B1 and B2 receptors comparing to normal cartilage. BK-mediated migration and integrin up-regulation was attenuated by B1 and B2 BK receptor siRNA or antagonist. Activations of phospholipase C (PLC), protein kinase Cdelta (PKCdelta), and NF-kappaB pathways after BK treatment was demonstrated, and BK-induced integrin expression and migration activity was inhibited by the specific inhibitor of PLC, PKCdelta, and NF-kappaB cascades. Taken together, our results indicated that BK enhances the migration of chondrosarcoma cells by increasing alpha2beta1 integrin expression through the BK receptors/PLC/PKCdelta/NF-kappaB signal transduction pathway.
The 2013 WHO antiretroviral therapy (ART) guidelines recommend dried blood spots (DBS) as an alternative specimen type for viral load (VL) monitoring. We assessed the programmatic utility of screening for antiretroviral (ARV) treatment failure (TF) at 5,000 and 1,000 copies/ml using DBS and dried plasma spots (DPS) with a commonly used VL assay, the Roche Cobas Ampliprep/Cobas TaqMan V.2.0 (CAP/CTM). Plasma, DBS, and DPS were prepared from 839 whole-blood specimens collected from patients on ART for >6 months at three public facilities in Namibia. Using the CAP/CTM test, VL were measured in plasma, DBS, and DPS, and the results were compared using the plasma VL as the reference standard. The clinical sensitivities, specificities, and positive (PPV) and negative predictive values (NPV) of DBS at ARV TF diagnostic thresholds of 5,000 copies/ml and 1,000 copies/ml were 0.99, 0.55, 0.33, and 0.99 and 0.99, 0.26, 0.29, and 0.99, respectively, and for DPS at TF diagnostic thresholds of 5,000 copies/ml and 1,000 copies/ml, they were 0.88, 0.98, 0.92, and 0.97 and 0.91, 0.96, 0.89, and 0.97, respectively. The prevalences of TF were overestimated in DBS by 33% and 57% at these two thresholds, respectively. A high rate of false-positive results would occur if the CAP/CTM with DBS were to be used to screen for ARV TF. WHO recommendations for DBS-based VL monitoring should be specific to the VL assay version and type. Despite the better performance of DPS, the programmatic utility for TF screening may be limited by requirements for processing the whole blood at the collection site.
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