Energy storage: A sandwiched and concentric architecture of RuO2/C/RuO2 has been successfully synthesized through a template‐assisted approach. This architecture exhibits novelty and innovation in the designed synthesis of hierarchical and functional systems and performed well in electrochemical testing, especially presenting excellent specific capacitance over very high scan rates (see figure).

Bacille Calmette-Guérin (BCG), an attenuated strain of Mycobacterium bovis, is the only vaccine available for tuberculosis (TB) control. BCG comprises a number of substrains that exhibit genetic and biochemical differences. Whether and how these differences affect BCG efficacy remain unknown. Compared to other BCG strains, BCG-Japan, -Moreau, and -Glaxo are defective in the production of phthiocerol dimycocerosates (PDIMs) and phenolic glycolipids (PGLs), two lipid virulence factors. To determine if the loss of PDIMs/PGLs affects BCG efficacy, we constructed a PDIM/PGL-deficient strain of BCG-Pasteur by deleting fadD28, and compared virulence, immunogenicity, and protective efficacy in animal models. SCID mouse infection experiments showed that ∆fadD28 was more attenuated than wild type (WT). The ∆fadD28 and WT strains induced equivalent levels of antigen specific IFN-γ by CD4+ and CD8+ T cells; however, ∆fadD28 was less effective against Mycobacterium tuberculosis challenge in both BALB/c mice and guinea pigs. These results indicate that the loss of PIDMs/PGLs reduces the virulence and protective efficacy of BCG. Since the loss of PDIMs/PGLs occurs naturally in a subset of BCG strains, it also suggests that these strains may have been over-attenuated, which compromises their effectiveness. Our finding has important implications for current BCG programs and future vaccine development.

Effective presentation of antigens by HLA class I molecules to CD8+ T cells is required for viral elimination and generation of long-term immunological memory. In this study, we applied a single-cell, multi-omic technology to generate the first unified ex vivo characterization of the CD8+ T cell response to SARS-CoV-2 across 4 major HLA class I alleles. We found that HLA genotype conditions key features of epitope specificity, TCR a/b sequence diversity, and the utilization of pre-existing SARS-CoV-2 reactive memory T cell pools. Single-cell transcriptomics revealed functionally diverse T cell phenotypes of SARS-CoV-2-reactive T cells, associated with both disease stage and epitope specificity. Our results show that HLA variations influence pre-existing immunity to SARS-CoV-2 and shape the immune repertoire upon subsequent viral exposure.

The ability of Mycobacterium tuberculosis (M. tb) to survive and persist in the host for decades in an asymptomatic state is an important aspect of tuberculosis pathogenesis. Although adaptation to hypoxia is thought to play a prominent role underlying M. tb persistence, how the bacteria achieve this goal is largely unknown. Rv0081, a member of the DosR regulon, is induced at the early stage of hypoxia while Rv3334 is one of the enduring hypoxic response genes. In this study, we uncovered genetic interactions between these two transcription factors. RNA-seq analysis of ΔRv0081 and ΔRv3334 revealed that the gene expression profiles of these two mutants were highly similar. We also found that under hypoxia, Rv0081 positively regulated the expression of Rv3334 while Rv3334 repressed transcription of Rv0081. In addition, we demonstrated that Rv0081 formed dimer and bound to the promoter region of Rv3334. Taken together, these data suggest that Rv0081 and Rv3334 work in the same regulatory pathway and that Rv3334 functions immediately downstream of Rv0081. We also found that Rv3334 is a bona fide regulator of the enduring hypoxic response genes. Our study has uncovered a regulatory pathway that connects the early and the enduring hypoxic response, revealing a transcriptional cascade that coordinates the temporal response of M. tb to hypoxia.

The live tuberculosis vaccine Mycobacterium bovis BCG (Bacille Calmette-Guérin) comprises a number of genetically distinct substrains. In BCG-Prague, phoP of the PhoP-PhoR two-component system is a pseudogene due to a single insertion mutation. We hypothesized that this mutation partially accounts for the low immunogenicity of BCG-Prague observed in the 1970s. In this study, we showed that complementation with the M. bovis allele of phoP restored BCG-Prague’s immunogenicity. Furthermore, we showed that overexpression of the M. bovis allele of phoP-phoR in BCG-Japan, a strain already containing a copy of phoP-phoR, further enhanced immunogenicity and protective efficacy. Vaccination of C57BL/6 mice with the recombinant strain rBCG-Japan/PhoPR induced higher levels of interferon-γ (IFN-γ) production by CD4+ T cells than that with the parental BCG. Guinea pigs vaccinated with rBCG-Japan/PhoPR were better protected against challenge with Mycobacterium tuberculosis than those immunized with the parental BCG, showing significantly longer survival time, reduced bacterial burdens, and less severe pathology. Taken together, our study has identified a genetic modification that could be generally applied to generate new recombinant BCG vaccines.

No abstract

Objective Sodium–glucose cotransporter 2 inhibitors (SGLT2i) have been associated with diabetic ketoacidosis at the time of colonoscopy. This study aimed to identify factors associated with ketone concentrations in SGLT2i‐treated type 2 diabetes compared with non‐SGLT2i‐treated diabetes, and those with impaired fasting glycaemia (IFG) and normoglycaemia. Design Cross‐sectional, multicentre, observational study June–December 2020 in four Australian tertiary hospitals. Participants Capillary glucose and ketones were measured in people undergoing colonoscopy: 37 SGLT2i‐treated and 105 non‐SGLT2i‐treated type 2 diabetes, 65 IFG and 151 normoglycaemia. Measurements Body mass index (BMI), age, glucose, fasting duration and where relevant, HbA1c and time since last SGLT2i dose. Results In SGLT2i‐treated diabetes, BMI (ρ = −0.43 [95% confidence interval: −0.67, −0.11]) and duration since last SGLT2i dose (ρ = −0.33 [−0.60, 0.00]) correlated negatively with increasing ketones, but there was no correlation with fasting duration. In non‐SGLT2i‐treated diabetes, BMI correlated negatively (ρ = −0.24 [−0.42, −0.05]) and fasting duration positively (ρ = 0.26 [0.07, 0.43]) with ketones. In IFG participants, only fasting duration correlated with ketones (ρ = 0.28 [0.03, 0.49]). In normoglycaemic participants, there were negative correlations with BMI (ρ = −0.20 [−0.35, −0.04]) and fasting glucose (ρ = −0.31 [−0.45, −0.15]) and positive correlations with fasting duration (ρ = 0.20 [0.04, 0.35]) and age (ρ = 0.19 [0.03, 0.34]). Multiple regression analysis of the entire cohort showed BMI, age and fasting glucose remained independently associated with ketones, but in SGLT2i‐treated participants only BMI remained independently associated. Conclusions In SGLT2i‐treated diabetes, lower BMI was a novel risk factor for higher ketones precolonoscopy. Pending larger confirmatory studies, extra vigilance for ketoacidosis is warranted in these people.

A clinical diagnosis of asthma is often considered when a child presents with recurrent cough, wheeze and breathlessness. However, there are many other causes of wheeze in a young child. These range from recurrent viral infections to chronic suppurative lung disease, gastro-oesophageal reflux disease and rare structural abnormalities. Arriving at a diagnosis includes taking into consideration the symptomatology, triggers, atopic features, family history, absence of red flags and therapeutic trial, where indicated.