Toto, we're not in Kansas anymore: First reported case of M. persicum septic arthritis.

In this report, we describe a case of septic arthritis caused by the newly described Mycobacterium persicum (formerly Mycobacterium kansasii complex). The patient's only significant exposure was home gardening. To our knowledge, this represents the first documented case of M. persicum infection in the United States and first septic arthritis.

Male genital trauma at a level 1 trauma center.

OBJECTIVES: To describe our experience with men admitted to a tertiary care hospital with genital injury. METHODS: Adult men with injuries of the genitals, admitted to our institution between January 2013 and June 2018, were identified from our institutional trauma registry. Patient charts were queried to extract mechanism, management, follow-up, and complications. RESULTS: 118 men met inclusion criteria. 39% and 61% sustained penetrating and blunt injuries, respectively. The most common mechanisms of penetrating trauma were external violence (48%) and self-inflicted injury (40%). The most common mechanisms of blunt trauma were motorcycle crash (33%) and sexual injury/intercourse (22%). 38% presented with penile and 71% with scrotal injuries. 48% of men with scrotal injuries had concomitant testis injury. 9.3% presented with both a penile and a scrotal injury. Concomitant urethral injuries were found in 17% of all genital injuries. Genital trauma was more common in the summer months. 74% of all genital injuries were managed operatively, with surgery more common after penetrating injury (89% vs 64%, p value < 0.01). 73% of 84 men with scrotal trauma were managed operatively. 27 men received surgical intervention for testis rupture, with a testicular salvage rate of 44%. 60 (51%) patients presented for follow-up. The median length of follow-up from initial injury was 29 (± 250) days. Of these, 9 (15%) patients developed one or more complications CONCLUSIONS: Genital injuries can occur via numerous mechanisms and frequently require operative intervention. Concomitant urethral injury is common. More work is needed to evaluate the long-term sequelae of these injuries.

Structure and analysis of nucleoside diphosphate kinase from Borrelia burgdorferi prepared in a transition-state complex with ADP and vanadate moieties.

Nucleoside diphosphate kinases (NDKs) are implicated in a wide variety of cellular functions owing to their enzymatic conversion of NDP to NTP. NDK from Borrelia burgdorferi (BbNDK) was selected for functional and structural analysis to determine whether its activity is required for infection and to assess its potential for therapeutic inhibition. The Seattle Structural Genomics Center for Infectious Diseases (SSGCID) expressed recombinant BbNDK protein. The protein was crystallized and structures were solved of both the apoenzyme and a liganded form with ADP and vanadate ligands. This provided two structures and allowed the elucidation of changes between the apo and ligand-bound enzymes. Infectivity studies with ndk transposon mutants demonstrated that NDK function was important for establishing a robust infection in mice, and provided a rationale for therapeutic targeting of BbNDK. The protein structure was compared with other NDK structures found in the Protein Data Bank and was found to have similar primary, secondary, tertiary and quaternary structures, with conserved residues acting as the catalytic pocket, primarily using His132 as the phosphohistidine-transfer residue. Vanadate and ADP complexes model the transition state of this phosphoryl-transfer reaction, demonstrating that the pocket closes when bound to ADP, while allowing the addition or removal of a γ-phosphate. This analysis provides a framework for the design of potential therapeutics targeting BbNDK inhibition.

Recombinant human G6PD for quality control and quality assurance of novel point-of-care diagnostics for G6PD deficiency.

BACKGROUND: A large gap for the support of point-of-care testing is the availability of reagents to support quality control (QC) of diagnostic assays along the supply chain from the manufacturer to the end user. While reagents and systems exist to support QC of laboratory screening tests for glucose-6-phosphate dehydrogenase (G6PD) deficiency, they are not configured appropriately to support point-of-care testing. The feasibility of using lyophilized recombinant human G6PD as a QC reagent in novel point-of-care tests for G6PD deficiency is demonstrated. METHODS: Human recombinant G6PD (r-G6PD) was expressed in Escherichia coli and purified. Aliquots were stored at -80°C. Prior to lyophilization, aliquots were thawed, and three concentrations of r-G6PD (representing normal, intermediate, and deficient clinical G6PD levels) were prepared and mixed with a protective formulation, which protects the enzyme activity against degradation from denaturation during the lyophilization process. Following lyophilization, individual single-use tubes of lyophilized r-G6PD were placed in individual packs with desiccants and stored at five temperatures for one year. An enzyme assay for G6PD activity was used to ascertain the stability of r-G6PD activity while stored at different temperatures. RESULTS: Lyophilized r-G6PD is stable and can be used as a control indicator. Results presented here show that G6PD activity is stable for at least 365 days when stored at -80°C, 4°C, 30°C, and 45°C. When stored at 55°C, enzyme activity was found to be stable only through day 28. CONCLUSIONS: Lyophilized r-G6PD enzyme is stable and can be used as a control for point-of-care tests for G6PD deficiency.

Biochemical and Structural Characterization of Selective Allosteric Inhibitors of the Plasmodium falciparum Drug Target, Prolyl-tRNA-synthetase.

Plasmodium falciparum (Pf) prolyl-tRNA synthetase (ProRS) is one of the few chemical-genetically validated drug targets for malaria, yet highly selective inhibitors have not been described. In this paper, approximately 40,000 compounds were screened to identify compounds that selectively inhibit PfProRS enzyme activity versus Homo sapiens (Hs) ProRS. X-ray crystallography structures were solved for apo, as well as substrate- and inhibitor-bound forms of PfProRS. We identified two new inhibitors of PfProRS that bind outside the active site. These two allosteric inhibitors showed >100 times specificity for PfProRS compared to HsProRS, demonstrating this class of compounds could overcome the toxicity related to HsProRS inhibition by halofuginone and its analogues. Initial medicinal chemistry was performed on one of the two compounds, guided by the cocrystallography of the compound with PfProRS, and the results can instruct future medicinal chemistry work to optimize these promising new leads for drug development against malaria.