High variance in quantification of at low bacterial loads and with differentially detectable mycobacteria.

We examined the correlation between three different methods of quantification: time to positivity (TTP), log CFU, and an assay to detect differentially detectable (DD Mtb) from three different prospective studies. Participants with DD Mtb have significantly more variation in the CFU/TTP correlation than participants with no DD Mtb ( < 0.001).

Rapidly adaptable automated interpretation of point-of-care COVID-19 diagnostics.

Background: Point-of-care diagnostic devices, such as lateral-flow assays, are becoming widely used by the public. However, efforts to ensure correct assay operation and result interpretation rely on hardware that cannot be easily scaled or image processing approaches requiring large training datasets, necessitating large numbers of tests and expert labeling with validated specimens for every new test kit format.

Methods: We developed a software architecture called AutoAdapt POC that integrates automated membrane extraction, self-supervised learning, and few-shot learning to automate the interpretation of POC diagnostic tests using smartphone cameras in a scalable manner.

Development of a rapid point-of-care test that measures neutralizing antibodies to SARS-CoV-2.

Background: After receiving a COVID-19 vaccine, most recipients want to know if they are protected from infection and for how long. Since neutralizing antibodies are a correlate of protection, we developed a lateral flow assay (LFA) that measures levels of neutralizing antibodies from a drop of blood. The LFA is based on the principle that neutralizing antibodies block binding of the receptor-binding domain (RBD) to angiotensin-converting enzyme 2 (ACE2).

Mass Spectrometric Analysis of Urine from COVID-19 Patients for Detection of SARS-CoV-2 Viral Antigen and to Study Host Response.

SARS-CoV-2 infection has become a major public health burden and affects many organs including lungs, kidneys, the liver, and the brain. Although the virus is readily detected and diagnosed using nasopharyngeal swabs by reverse transcriptase polymerase chain reaction (RT-PCR), detection of its presence in body fluids is fraught with difficulties. A number of published studies have failed to detect viral RNA by RT-PCR methods in urine.

Retrospective clinical evaluation of 4 lateral flow assays for the detection of SARS-CoV-2 IgG.

In a Clinical Laboratory Improvement Amendments laboratory setting, we evaluated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG detection with 4 lateral flow immunoassays [LFIAs; 2 iterations from BTNX Inc. (n = 457) and 1 each from ACON Laboratories (n = 200) and SD BIOSENSOR (n = 155)]. In a cohort of primarily hospitalized, reverse-transcription polymerase chain reaction-confirmed coronavirus disease 2019 cases, sensitivity at ≥14 days from symptom onset was: BTNX kit 1, 95%; BTNX kit 2, 91%; ACON, 95%; and SD, 92%.

Urinary biomarkers of mycobacterial load and treatment response in pulmonary tuberculosis.

BACKGROUNDControl of the tuberculosis (TB) pandemic remains hindered in part by a lack of simple and accurate measures of treatment efficacy, as current gold standard markers rely on sputum-based assays that are slow and challenging to implement. However, previous work identified urinary N1, N12-diacetylspermine (DiAcSpm), neopterin, hydroxykynurenine, N-acetylhexosamine, ureidopropionic acid, sialic acid, and mass-to-charge ratio (m/z) 241.0903 as potential biomarkers of active pulmonary TB (ATB).

Dual-Pharmacophore Pyrithione-Containing Cephalosporins Kill Both Replicating and Nonreplicating .

The historical view of β-lactams as ineffective antimycobacterials has given way to growing interest in the activity of this class against () in the presence of a β-lactamase inhibitor. However, most antimycobacterial β-lactams kill only or best when the bacilli are replicating. Here, a screen of 1904 β-lactams led to the identification of cephalosporins substituted with a pyrithione moiety at C3' that are active against under both replicating and nonreplicating conditions, neither activity requiring a β-lactamase inhibitor.

Opposing reactions in coenzyme A metabolism sensitize to enzyme inhibition.

(Mtb) is the leading infectious cause of death in humans. Synthesis of lipids critical for Mtb's cell wall and virulence depends on phosphopantetheinyl transferase (PptT), an enzyme that transfers 4'-phosphopantetheine (Ppt) from coenzyme A (CoA) to diverse acyl carrier proteins. We identified a compound that kills Mtb by binding and partially inhibiting PptT.

Differentially Detectable Mycobacterium tuberculosis Cells in Sputum from Treatment-Naive Subjects in Haiti and Their Proportionate Increase after Initiation of Treatment.

Recent reports indicate that the sputum of 80% or more of treatment-naive subjects with tuberculosis recruited in England or South Africa contained more viable cells detected by limiting dilution (LD) in liquid culture than detected as CFU. Efforts to generate such differentially detectable (DD) populations have been difficult to reproduce, and the LD assay is prone to artifact. Here, we applied a stringent version of the LD assay to sputum from 33 treatment-naive, HIV-negative Haitian subjects with drug-sensitive tuberculosis (TB) and to a second sputum sample after two weeks of standard treatment with isoniazid, rifampin, pyrazinamide, and ethambutol (HRZE) for 13 of these subjects.