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Objectives: Interferon-γ release assays (IGRAs) are widely used in public health practice to diagnose latent tuberculosis. During the COVID-19 pandemic and rollout of COVID-19 vaccination, it has remained unclear whether COVID-19 vaccines interfere with IGRA readouts. Methods: We prospectively recruited healthcare workers during their annual occupational health examinations in 2021. Baseline IGRA readouts were compared with follow-up data after the participants had received two doses of COVID-19 vaccination. Results: A total of 134 baseline IGRA-negative cases (92 with ChAdOx1 vaccine, 27 with mRNA-1273 vaccine, and 15 with heterologous vaccination) and seven baseline IGRA-positive cases were analyzed. Among the baseline IGRA-negative cases, there were decreased interferon-γ concentrations over the Nil (P = 0.005) and increased Mitogen-Nil (P < 0.001) values after vaccination. For TB2-Nil value, a similar trend (P = 0.057) of increase was observed. Compared with the 0.35 IU/ml threshold, the baseline and follow-up readout differences were less than |± 0.10| IU/ml over the TB1-Nil and TB2-Nil values in >90% baseline IGRA-negative cases. No significant readout difference was observed among baseline IGRA-positive cases. Conclusion: COVID-19 vaccination did not change IGRA interpretation in most cases. Cases showing conversion/borderline IGRA readouts should be given special consideration.

Background: The clinical utilisation of deep sequencing in HIV treatment has been hindered due to its unknown correlation with standard Sanger genotyping and the undetermined value of minority drug resistance mutation (DRM) detection. Objectives: To compare deep sequencing performance to standard Sanger genotyping with clinical samples, in an effort to delineate the correlation between the results from the two methods and to find the optimal deep sequencing threshold for clinical utilisation. Methods: We conducted a retrospective study using stored plasma collected from August 2014 to March 2018 for HIV genotyping with the commercial Sanger genotyping kit. Samples with available Sanger genotyping reports were further deep sequenced. Drug resistance was interpreted according to the Stanford HIV drug resistance database algorithm. Results: At 15–25% minority detection thresholds, 9–15% cases had underestimated DRMs by Sanger sequencing. The concordance between the Sanger and deep sequencing reports was 68–82% in protease-reverse transcriptase region and 88–97% in integrase region at 5–25% thresholds. The undetected drug resistant minority variants by Sanger sequencing contributed to the lower negative predictive value of Sanger genotyping in cases harbouring DRMs. Conclusions: Use of deep sequencing improved detection of antiretroviral resistance mutations especially in cases with virological failure or previous treatment interruption. Deep sequencing with 10–15% detection thresholds may be considered a suitable substitute for Sanger sequencing on antiretroviral DRM detection. Keywords: HIV, Next-generation sequencing, Deep sequencing, Drug resistance, Sanger sequencing

Background: Wound healing and skin tissue engineering are mediated, in part, by interactions between cells and the extracellular matrix (ECM). A subset of the ECM, basement membranes (BM), plays a vital role in regulating proper skin healing and function. Methods: ECM-rich, tissue-specific hydrogels were extracted and assembled from dermis samples. These hydrogels contain BM proteins vital to skin regeneration, including laminin β3, collagen IV, and collagen VII. The extracts could be assembled to form hydrogels by either temperature or pH mechanism, with the mechanical properties and structure varying with the mechanism of assembly. A wound healing model was developed to investigate the ability of these hydrogels to enhance healing with a single application in vivo. Results: The pH, but not temperature gels were easily applied to the wounds. There were no signs of increased inflammation due to the application of the hydrogels. The width of granulation tissue at the first week was reduced (p = 0.064) relative to controls with the application of hydrogel. There were no changes in wound closure rates or vessel density. Conclusions: Dermis-derived hydrogels contain BM proteins important for skin regeneration. They can be easily applied, but their poor mechanical strength and rapid degradation may hinder their biological effects.

Objective: Breast cancer treatment has evolved to the modern skin-sparing mastectomy and nipple-sparing mastectomy. To better perform these surgeries, minimally invasive techniques using the endoscope, or Da Vinci Robotic Surgery platform have been developed. The deep inferior epigastric perforator (DIEP) flap is the gold standard in breast reconstruction, but it is still not commonly performed after minimally invasive mastectomy due technical difficulty. Here the authors introduced six key steps to a successful aesthetic autologous free flap reconstruction in in minimally invasive mastectomies. Methods: There are six main steps to our technique: placement of mastectomy incision, precise flap design after angiography studies, trial of shaping, transcutaneous medial suture, footprint recreation and postoperative shaping with bra. Between November 2018 and July 2022, a total of 67 immediate breast reconstructions using free perforator flaps were performed in 63 patients after minimally invasive nipple-sparing mastectomy. Results: The results from the minimally invasive mastectomy group were compared with a group of conventional mastectomy patients (n=41) performed during the same period. There were no significant differences in flap exploration rates. One hundred percent of the flaps survived. In the minimally invasive group, the final scar was placed in the lateral region, where it would be hidden from the anterior view. Only 70.7% of the conventional mastectomy group could achieve a hidden lateral scar (P<0.001). The aesthetic revision rates were similar between two groups. Conclusion: With attention to the six steps above, autologous free flap reconstruction can be offered reliably in the setting of minimally invasive mastectomy. [ABSTRACT FROM AUTHOR]