Search

Despite the goal set by WHO to eliminate hepatitis C virus (HCV) as a public health threat, uptake of HCV testing and treatment remains low. To achieve this target, evidence-based interventions are needed to address the barriers to care for people with, or at risk of, HCV infection. We aimed to assess the efficacy of interventions to improve HCV antibody testing, HCV RNA testing, linkage to HCV care, and treatment initiation.

ABSTRACTCavity volume is an important clinical index for the assessment of the healing process and effectiveness of treatment applied on chronic ulcers. Recently, 3D scanners have proven to effectively track ulcer’s volume evolution. However, photogrammetry presents itself as a low cost and portable alternative. We conducted a comparative study between photogrammetric and 3D scanner-based volume estimation of small skin ulcers. A total of 24 cutaneous leishmaniasis ulcers’ virtual models were generated using a commercial laser scanner and a full-HD portable camera. The reconstruction from videos was performed using open-source software (VisualSFM). The results revealed a similar performance when compared to 3D Scan-based volume estimation with a median deviation and percentile error of 33.68 mm3and 21.10%, respectively. In addition, the method proved to effectively follow the same tendency in the assessment of healing ulcers when compared to the 3D-scanner. Moreover, when comparing the two virtual models trough residual differences after ICP registration the mean error and standard deviation was 0.36 ± 0.27 mm.

Introduction: Leishmaniasis is a neglected tropical disease that manifests as three major disease phenotypes: cutaneous, mucocutaneous, and visceral. In this preliminary study, we quantified virulence factor (VF) RNA transcript expression in Leishmaniaspecies, stratified by geographic origin and propensity for specific disease phenotypes.Methods: Cultured promastigotes of 19 Leishmaniaclinical and ATCC isolates were extracted for total cellular RNA, cDNA was reverse transcribed, and qPCR assays were performed to quantify VF RNA transcript expression for hsp23, hsp70, hsp83, hsp100, mpi, cpb, and gp63.Results: Comparison of visceralizing species (Leishmania donovani, Leishmania chagasi, and Leishmania infantum) versus non-visceralizing species [Leishmania (Viannia) spp., Leishmania tropica, Leishmania major, Leishmania mexicana, and Leishmania amazonensis] revealed a significantly greater pooled transcript expression for visceralizing species (p = 0.0032). Similarly, Old World species demonstrated significantly higher VF RNA transcript expression than New World species (p = 0.0015). On a per-gene basis, species with a propensity to visceralize ubiquitously expressed higher levels of gp63 (p = 0.005), cpb (p = 0.0032), mpi (p = 0.0032), hsp23 (p = 0.0039), hsp70 (p = 0.0032), hsp83 (p = 0.0032), and hsp100 (p = 0.0032).Conclusion: Here, we provide quantitative, preliminary evidence of elevated VF RNA transcript expression driven largely by the visceralizing causative species of Leishmania. This work highlights the extensive heterogeneity in pathogenicity mechanisms between Leishmaniaspecies, which may partly underpin the fatal progression of visceral leishmaniasis.

ABSTRACTEarlier histopathology studies suggest that parasite loads may differ between cutaneous leishmaniasis (CL) and mucosal leishmaniasis (ML) lesions and between acute and chronic CL. Formal demonstration requires highly sensitive detection and accurate quantification of Leishmaniain human lesional tissue. In this study, we developed a quantitative real-time PCR (qPCR) assay targeting minicircle kinetoplast DNA (kDNA) to detect and quantify Leishmania(Viannia) parasites. We evaluated a total of 156 lesion biopsy specimens from CL or ML suspected cases and compared the quantitative performance of our kDNA qPCR assay with that of a previously validated qPCR assay based on the glucose-6-phosphate dehydrogenase (G6PD) gene. We also examined the relationship between parasite load and clinical parameters. The kDNA qPCR sensitivity for Leishmaniadetection was 97.9%, and its specificity was 87.5%. The parasite loads quantified by kDNA qPCR and G6PDqPCR assays were highly correlated (r= 0.87; P< 0.0001), but the former showed higher sensitivity (P= 0.000). CL lesions had 10-fold-higher parasite loads than ML lesions (P= 0.009). Among CL patients, the parasite load was inversely correlated with disease duration (P= 0.004), but there was no difference in parasite load according to the parasite species, the patient's age, and number or area of lesions. Our findings confirm that CL and recent onset of disease (<3 months) are associated with a high parasite load. Our kDNA qPCR assay proved highly sensitive and accurate for the detection and quantification of Leishmania(Viannia) spp. in lesion biopsy specimens. It has potential application as a diagnostic and follow-up tool in American tegumentary leishmaniasis.

ABSTRACTWe present an algorithm based on three PCR assays for Leishmania(Viannia) species identification and assessed its performance using 70 specimens from Peruvian patients. The succession of the assayed targets can be ordered according to species prevalence. Sequential progression through the algorithm reduced the number of samples here studied by approximately 30% after each step.

We present an algorithm based on three PCR assays for Leishmania (Viannia) species identification and assessed its performance using 70 specimens from Peruvian patients. The succession of the assayed targets can be ordered according to species prevalence. Sequential progression through the algorithm reduced the number of samples here studied by approximately 30% after each step.