Active case-finding of tuberculosis compared with symptom-driven standard of care: a modelling analysis.

BACKGROUND: In settings with large case detection gaps, active case-finding (ACF) may play a critical role in the uberculosis (TB) response. However, ACF is resource intensive, and its effectiveness depends on whether people detected with TB through ACF might otherwise spontaneously resolve or be diagnosed through routine care. We analysed the potential effectiveness of ACF for TB relative to the counterfactual scenario of routine care alone. METHODS: We constructed a Markov simulation model of TB natural history, diagnosis, symptoms, ACF and treatment, using a hypothetical reference setting using data from South East Asian countries. We calibrated the model to empirical data using Bayesian methods, and simulated potential 5-year outcomes with an 'aspirational' ACF intervention (reflecting maximum possible effectiveness) compared with the standard-of-care outcomes. RESULTS: Under the standard of care, 51% (95% credible interval, CrI: 31%, 75%) of people with prevalent TB at baseline were estimated to be diagnosed and linked to care over 5 years. With aspirational ACF, this increased to 88% (95% CrI: 84%, 94%). Most of this difference represented people who were diagnosed and treated through ACF but experienced spontaneous resolution under standard-of-care. Aspirational ACF was projected to reduce the average duration of TB disease by 12 months (95% CrI: 6%, 18%) and TB-associated disability-adjusted life-years by 71% (95% CrI: 67%, 76%). CONCLUSION: These data illustrate the importance of considering outcomes in a counterfactual standard of care scenario, as well as trade-offs between overdiagnosis and averted morbidity through earlier diagnosis-not just for TB, but for any disease in which population-based screening is recommended.

Role of Wrist Arthroscopy in Juvenile Inflammatory Arthritis.

Background and Purposes The wrist is the fourth most common joint to be involved in juvenile inflammatory arthritis (JIA), which is a common rheumatological condition affecting children. Wrist arthroscopy is well established in rheumatoid arthritis, but remains unexplored in JIA. The aim of this study is to investigate the role of wrist arthroscopy in JIA, with focus on those who are refractory to medical management. Methods This is a prospective observational study, including consecutive patients with JIA undergoing arthroscopy between January 2016 and December 2020. Those over the age of 18 years and those with other rheumatological diagnoses were excluded. Data including pre-, intra-, and postoperative variables, demographics, and patient-reported outcomes were collated and are reported using standard measures. Results A total of 15 patients underwent arthroscopy ( n = 20 wrists). Synovitis was noted in all wrists on arthroscopy and synovectomy was performed in all cases. Other procedures were performed as indicated during the procedure. The median follow-up duration was 11.3 (interquartile range [IQR] 8.1-24.2) months. Median reduction of 4 (IQR 2.25-6) points on the Visual Analogue Score for pain on loading was noted postoperatively. Grip strength was improved in n = 11/20 wrists and functional improvement was noted in n = 18/20 wrists. Restriction of range of motion was achieved with a shrinkage procedure in patients with hypermobile joints. There were no postoperative complications, and no patients were lost to follow-up. Conclusion In experienced hands, wrist arthroscopy is feasible, safe, and efficacious in the management of JIA, among patients who are refractory to medical management. Level of Evidence This is a Level II study.

Costs and cost-effectiveness of a comprehensive tuberculosis case finding strategy in Zambia.

INTRODUCTION: Active-case finding (ACF) programs have an important role in addressing case detection gaps and halting tuberculosis (TB) transmission. Evidence is limited on the cost-effectiveness of ACF interventions, particularly on how their value is impacted by different operational, epidemiological and patient care-seeking patterns. METHODS: We evaluated the costs and cost-effectiveness of a combined facility and community-based ACF intervention in Zambia that utilized mobile chest X-ray with computer-aided reading/interpretation software and laboratory-based Xpert MTB/RIF testing. Programmatic costs (in 2018 US dollars) were assessed from the health system perspective using prospectively collected cost and operational data. Cost-effectiveness of the ACF intervention was assessed as the incremental cost per TB death averted over a five-year time horizon using a multi-stage Markov state-transition model reflecting patient symptom-associated care-seeking and TB care under ACF compared to passive care. RESULTS: Over 18 months of field operations, the ACF intervention costed $435 to diagnose and initiate treatment for one person with TB. After accounting for patient symptom-associated care-seeking patterns in Zambia, we estimate that this one-time ACF intervention would incrementally diagnose 407 (7,207 versus 6,800) TB patients and avert 502 (611 versus 1,113) TB-associated deaths compared to the status quo (passive case finding), at an incremental cost of $2,284 per death averted over the next five-year period. HIV/TB mortality rate, patient symptom-associated care-seeking probabilities in the absence of ACF, and the costs of ACF patient screening were key drivers of cost-effectiveness. CONCLUSIONS: A one-time comprehensive ACF intervention simultaneously operating in public health clinics and corresponding catchment communities can have important medium-term impact on case-finding and be cost-effective in Zambia. The value of such interventions increases if targeted to populations with high HIV/TB mortality, substantial barriers (both behavioral and physical) to care-seeking exist, and when ACF interventions can optimize screening by achieving operational efficiency.

The Preferred Qualities of Human Immunodeficiency Virus Testing and Self-Testing Among Men Who Have Sex With Men: A Discrete Choice Experiment.

OBJECTIVES: Human immunodeficiency virus self-testing (HIVST) is a promising approach to improve HIV testing coverage. We aimed to understand HIV testing preferences of men who have sex with men (MSM) to optimize HIVST implementation. METHODS: Discrete choice experiments (DCEs) were conducted among HIV-negative MSM living in Australia and aged ≥18 years. Men completed 1 of 2 DCEs: DCETest for preferred qualities of HIV testing (price, speed, window period, test type, and collector of specimen) and DCEKits for preferred qualities of HIVST kits (price, location of access, packaging, and usage instructions). Latent class conditional logit regression was used to explore similarities (or "classes") in preference behavior. RESULTS: Overall, the study recruited 1606 men: 62% born in Australia, who had an average age of 36.0 years (SD 11.7), and a self-reported median of 4 (interquartile range 2-8) sexual partners in the last 6 months. The respondents to DCETest was described by 4 classes: "prefer shorter window period" (36%), "prefer self-testing" (27%), "prefer highly accurate tests" (22%), and "prefer low prices" (15%). Respondents to DCEKits were described by 4 classes: "prefer low prices" (48%), "prefer retail access (from pharmacy or online stores)" (29%), "prefer access at sex venues" (15%), and "prefer to buy from healthcare staff" (12%). Preferences varied by when someone migrated to Australia, age, frequency of testing, and number of sexual partners. CONCLUSION: A subset of MSM, particularly infrequent testers, value access to HIVST. Expanding access to HIVST kits through online portals and pharmacies and at sex venues should be considered.

Artifact-free whole-slide imaging with structured illumination microscopy and Bayesian image reconstruction.

BACKGROUND: Structured illumination microscopy (SIM) is a method that can be used to image biological samples and can achieve both optical sectioning and super-resolution effects. Optimization of the imaging set-up and data-processing methods results in high-quality images without artifacts due to mosaicking or due to the use of SIM methods. Reconstruction methods based on Bayesian estimation can be used to produce images with a resolution beyond that dictated by the optical system. FINDINGS: Five complete datasets are presented including large panoramic SIM images of human tissues in pathophysiological conditions. Cancers of the prostate, skin, ovary, and breast, as well as tuberculosis of the lung, were imaged using SIM. The samples are available commercially and are standard histological preparations stained with hematoxylin-eosin. CONCLUSION: The use of fluorescence microscopy is increasing in histopathology. There is a need for methods that reduce artifacts caused by the use of image-stitching methods or optical sectioning methods such as SIM. Stitched SIM images produce results that may be useful for intraoperative histology. Releasing high-quality, full-slide images and related data will aid researchers in furthering the field of fluorescent histopathology.

Colorimetric Assay Reports on Acyl Carrier Protein Interactions.

The ability to produce new molecules of potential pharmaceutical relevance via combinatorial biosynthesis hinges on improving our understanding of acyl-carrier protein (ACP)-protein interactions. However, the weak and transient nature of these interactions makes them difficult to study using traditional spectroscopic approaches. Herein we report that converting the terminal thiol of the E. coli ACP 4'-phosphopantetheine arm into a mixed disulfide with 2-nitro-5-thiobenzoate ion (TNB-) activates this site to form a selective covalent cross-link with the active site cysteine of a cognate ketoacyl synthase (KS). The concomitant release of TNB2-, which absorbs at 412 nm, provides a visual and quantitative measure of mechanistically relevant ACP-KS interactions. The colorimetric assay can propel the engineering of biosynthetic routes to novel chemical diversity by providing a high-throughput screen for functional hybrid ACP-KS partnerships as well as the discovery of novel antimicrobial agents by enabling the rapid identification of small molecule inhibitors of ACP-KS interactions.

Effect of helical flanking sequences on the morphology of polyglutamine-containing fibrils.

A peptide model system has been developed to study the effects of helical flanking sequences on polyglutamine aggregation. In a companion manuscript, the kinetics of aggregation are described, comparing the influence of a well-defined heterotetrameric coiled coil to that of the helix-rich structure found in Htt(NT), a 17-residue flanking sequence found in the huntingtin protein, on polyglutamine aggregation. Here, the morphological characterization of the resultant fibrils that form for a set of peptides is reported, only one of which, KKQ25KK, has been previously studied. A careful analysis of TEM and AFM images of KKQ25KK confirms that it forms bundled fibrils of varying length and reveals, unexpectedly, that they are composed of fully extended cross-ß-strands. Second, it is shown that helical flanking sequences do not disrupt the assembly of a core cross-ß-sheet structure, but such flanking sequences can influence higher order processes, such as inhibiting the bundling of the fibrils.

Ultrasonographic phases in gap healing following Ponseti-type Achilles tenotomy.

BACKGROUND: The Ponseti technique is well established in the management of clubfoot deformity, and an Achilles tenotomy is frequently performed to facilitate dorsiflexion of the foot. This report describes the ultrasonographic phases of healing of the tendon gap created by the Achilles tenotomy and how the healing varies, if at all, with patient age. METHODS: A prospective ultrasonographic study of gap healing following a Ponseti-type tenotomy in twenty-seven tendons in twenty patients with idiopathic congenital clubfoot was performed. Serial ultrasound examinations (both static and dynamic) were performed at three, six, and twelve weeks after the tenotomy. The casts were removed routinely three weeks after the tenotomy. The end point of healing was defined as the observation of tendon homogeneity across the gap zone on ultrasound, with the divided tendon ends being indistinct. RESULTS: Three phases of healing were apparent on ultrasound assessment at three, six, and twelve weeks after the tenotomy. These sequential phases are similar to those previously described in the healing of tendons with no gap. The transition to normal structure was frequently demonstrated by ultrasonography only at twelve weeks (in thirteen of twenty-one tendons). CONCLUSIONS: Although there is evidence of continuity of the Achilles tendon by three weeks after tenotomy, healing is not complete until at least twelve weeks. The time needed for the tendon to completely heal should be taken into consideration before a revision Achilles tenotomy is planned.

Radiation exposure during in-situ pinning of slipped capital femoral epiphysis hips: does the patient positioning matter?

Multiple radiographic images may be necessary during the standard procedure of in-situ pinning of slipped capital femoral epiphysis (SCFE) hips. This procedure can be performed with the patient positioned on a fracture table or a radiolucent table. Our study aims to look at any differences in the amount and duration of radiation exposure for in-situ pinning of SCFE performed using a traction table or a radiolucent table. Sixteen hips in thirteen patients who were pinned on radiolucent table were compared for the cumulative radiation exposure to 35 hips pinned on a fracture table in 33 patients during the same time period. Cumulative radiation dose was measured as dose area product in Gray centimeter2 and the duration of exposure was measured in minutes. Appropriate statistical tests were used to test the significance of any differences. Mean cumulative radiation dose for SCFE pinned on radiolucent table was statistically less than for those pinned on fracture table (P<0.05). The mean duration of radiation exposure on either table was not significantly different. Lateral projections may increase the radiation doses compared with anteroposterior projections because of the higher exposure parameters needed for side imaging. Our results showing decreased exposure doses on the radiolucent table are probably because of the ease of a frog leg lateral positioning obtained and thereby the ease of lateral imaging. In-situ pinning of SCFE hips on a radiolucent table has an additional advantage that the radiation dose during the procedure is significantly less than that of the procedure that is performed on a fracture table.

Self assembly of coiled-coil peptide-porphyrin complexes.

We are interested in the controlled assembly of photoelectronic materials using peptides as scaffolds and porphyrins as the conducting material. We describe the integration of a peptide-based polymer strategy with the ability of designed basic peptides to bind anionic porphyrins in order to create regulated photoelectronically active biomaterials. We have described our peptide system in earlier work, which demonstrates the ability of a peptide to form filamentous materials made up of self-assembling coiled-coil structures. We have modified this peptide system to include lysine residues appropriately positioned to specifically bind meso-tetrakis(4-sulfonatophenyl)porphine (TPPS(4)), a porphyrin that contains four negatively charged sulfonate groups at neutral pH. We measure the binding of TPPS(4) to our peptide using UV--visible and fluorescence spectroscopies to follow the porphyrin signature. We determine the concomitant acquisition of helical secondary structure in the peptide upon TPPS(4) binding using circular dichroism spectropolarimetry. This binding fosters polymerization of the peptide, as shown by absorbance extinction effects in the peptide CD spectra. The morphologies of the peptide/porphyrin complexes, as imaged by atomic force microscopy, are consistent with the coiled-coil polymers that we had characterized earlier, except that the heights are slightly higher, consistent with porphyrin binding. Evidence for exciton coupling in the copolymers is shown by red-shifting in the UV--visible data, however, the coupling is weak based on a lack of fluorescence quenching in fluorescence experiments.

Refolding of human beta-1-2 GlcNAc transferase (GnT1) and the role of its unpaired Cys 121.

Human beta1-2N-acetylglucosaminyltransferase (hGnT1) lacking the first 103 amino acids was expressed as a maltose binding protein (MBP) fusion protein in inclusion bodies (IBs) in Escherichia coli and refolded using an oxido-shuffling method. GnT1 mutants were prepared by replacing a predicted unpaired cysteine (C121) with alanine (C121A), serine (C121S), threonine (C121T) or aspartic acid (C121D). A double mutant R120A/C121H, was generated to mimic Gly14, the Caenorhabditis elegans GnT1 counterpart to hGNT1. Each mutant hGnT1 was constructed as an MBP fusion protein and resultant IBs were isolated and refolded. Wild type hGnT1 and mutants C121A, C121S and R120A/C121H transferred UDP-GlcNAc to the glycoprotein acceptor Man(5)-RNAse B, whereas mutants C121T and C121D were inactive. These findings indicated that cysteine 121 has a structural role in maintaining active site geometry of hGnT1, rather than a catalytic role, and illustrates for the first time the potential utility of E. coli as an expression system for hGnT1.

Carpal-tarsal osteolysis with elbow involvement.

Carpal-tarsal osteolysis is a rare condition that manifests as the progressive resorption of carpal and tarsal bones in young children. The diagnosis of this condition is often difficult and delayed as the initial clinical presentation is non-specific. Radiographic changes occur gradually, are often not seen at presentation and depend on recognising loss of bone in the ossification centres of the carpus and tarsus. MRI demonstrates morphological abnormalities in the cartilaginous, as well as the osseous components, of the developing carpal and tarsal bones and therefore may be helpful in predating the radiographic changes. Ultrasound appears to contribute little to the diagnosis and may be misleading. Exclusion of other conditions, particularly juvenile idiopathic arthritis, is important in making the diagnosis. MRI can be useful in excluding an inflammatory arthropathy, and suggesting the diagnosis of carpal-tarsal osteolysis.

Childhood idiopathic chondrolysis of the hip: MRI features.

BACKGROUND: Childhood idiopathic chondrolysis of the hip (ICH) causes progressive destruction of the articular cartilage of the hip joint with associated bone remodelling. The MRI features of this disease have not previously been described. OBJECTIVE: To document the MRI features of childhood ICH and determine which features may help distinguish ICH from other causes of hip joint destruction in the paediatric population. MATERIALS AND METHODS: A retrospective review of the MRI examinations of children with clinically diagnosed ICH. All children had undergone synovial biopsy and/or joint aspiration with plain hip radiography to exclude causes of secondary chondrolysis. RESULTS: Ten MRI examinations were performed on six children. Cartilage loss, small hip joint effusions, bone remodelling and significant regional muscle wasting were seen in all children. Cartilage loss was most severe in the central part of the joint. Synovial enhancement was not a constant feature of ICH. Serial imaging in three children showed disease progression. CONCLUSIONS: MRI in ICH clearly demonstrates cartilage loss and enables delineation of bone and muscle abnormalities. It is helpful in the differential diagnosis of hip joint disease in children and may provide further information on the progression and aetiology of ICH.