ANTI-TUBERCULAR ACTIVITY OF EDTA AND HOUSEHOLD CHEMICALS AGAINST MYCOBACTERIUM SMEGMATIS, A SURROGATE FOR MULTI-DRUG RESISTANT TUBERCULOSIS

Drug discovery efforts are increasingly being directed at re-purposing old drugs for use in treatment of multidrug resistant tuberculosis (MDRTB) which continues to pose serious health challenges worldwide. Recent studies suggest that Mycobacterium smegmatis, with innate resistance to isoniazid, could be used as a surrogate for MDRTB screening in laboratories without adequate containment facilities. The current study utilized resazurin microtiter assay plate (REMA) to screen common household chemicals and non-steroidal anti-inflammatory drugs (NSAIDs) for anti-tubercular activity against Mycobacterium smegmatis, as a non-pathogenic surrogate of MDRTB. A ligand-based approach was adopted in selecting household chemicals; using molecular docking tools to probe for binding affinity to Enoyl-[acyl-carrier-protein] reductase (InhA), the main target of isoniazid. Among household chemicals and analgesics studied, EDTA and lauric acid showed the highest activity with minimum inhibitory concentration (MIC) of 31 μg/mL and 7.8 μg/mL respectively, while Ibuprofen and aspirin exhibited activity with MIC of 125 μg/mL. Taken together, this study demonstrates the potential use of EDTA, lauric acid or NSAIDs in treatment of drug-resistant tuberculosis, a major contribution of the current stud

ANTI-TUBERCULAR ACTIVITY OF EDTA AND HOUSEHOLD CHEMICALS AGAINST MYCOBACTERIUM SMEGMATIS, A SURROGATE FOR MULTI-DRUG RESISTANT TUBERCULOSIS

Drug discovery efforts are increasingly being directed at re-purposing old drugs for use in treatment of multidrug resistant tuberculosis (MDRTB) which continues to pose serious health challenges worldwide. Recent studies suggest that Mycobacterium smegmatis, with innate resistance to isoniazid, could be used as a surrogate for MDRTB screening in laboratories without adequate containment facilities. The current study utilized resazurin microtiter assay plate (REMA) to screen common household chemicals and non-steroidal anti-inflammatory drugs (NSAIDs) for anti-tubercular activity against Mycobacterium smegmatis, as a non-pathogenic surrogate of MDRTB. A ligand-based approach was adopted in selecting household chemicals; using molecular docking tools to probe for binding affinity to Enoyl-[acyl-carrier-protein] reductase (InhA), the main target of isoniazid. Among household chemicals and analgesics studied, EDTA and lauric acid showed the highest activity with minimum inhibitory concentration (MIC) of 31 μg/mL and 7.8 μg/mL respectively, while Ibuprofen and aspirin exhibited activity with MIC of 125 μg/mL. Taken together, this study demonstrates the potential use of EDTA, lauric acid or NSAIDs in treatment of drug-resistant tuberculosis, a major contribution of the current stud

Helium Hand – High Pressure Injection Injury

Teaching Point: High-pressure injection injuries are clinically significant injuries which may be underappreciated on initial physical exam and which require a high index of suspicion and early clinical intervention to avoid negative outcomes

Identification of Birds through DNA Barcodes

Short DNA sequences from a standardized region of the genome provide a DNA barcode for identifying species. Compiling a public library of DNA barcodes linked to named specimens could provide a new master key for identifying species, one whose power will rise with increased taxon coverage and with faster, cheaper sequencing. Recent work suggests that sequence diversity in a 648-bp region of the mitochondrial gene, cytochrome c oxidase I (COI), might serve as a DNA barcode for the identification of animal species. This study tested the effectiveness of a COI barcode in discriminating bird species, one of the largest and best-studied vertebrate groups. We determined COI barcodes for 260 species of North American birds and found that distinguishing species was generally straightforward. All species had a different COI barcode(s), and the differences between closely related species were, on average, 18 times higher than the differences within species. Our results identified four probable new species of North American birds, suggesting that a global survey will lead to the recognition of many additional bird species. The finding of large COI sequence differences between, as compared to small differences within, species confirms the effectiveness of COI barcodes for the identification of bird species. This result plus those from other groups of animals imply that a standard screening threshold of sequence difference (10× average intraspecific difference) could speed the discovery of new animal species. The growing evidence for the effectiveness of DNA barcodes as a basis for species identification supports an international exercise that has recently begun to assemble a comprehensive library of COI sequences linked to named specimens

Game Theory of Social Distancing in Response to an Epidemic

Social distancing practices are changes in behavior that prevent disease transmission by reducing contact rates between susceptible individuals and infected individuals who may transmit the disease. Social distancing practices can reduce the severity of an epidemic, but the benefits of social distancing depend on the extent to which it is used by individuals. Individuals are sometimes reluctant to pay the costs inherent in social distancing, and this can limit its effectiveness as a control measure. This paper formulates a differential-game to identify how individuals would best use social distancing and related self-protective behaviors during an epidemic. The epidemic is described by a simple, well-mixed ordinary differential equation model. We use the differential game to study potential value of social distancing as a mitigation measure by calculating the equilibrium behaviors under a variety of cost-functions. Numerical methods are used to calculate the total costs of an epidemic under equilibrium behaviors as a function of the time to mass vaccination, following epidemic identification. The key parameters in the analysis are the basic reproduction number and the baseline efficiency of social distancing. The results show that social distancing is most beneficial to individuals for basic reproduction numbers around 2. In the absence of vaccination or other intervention measures, optimal social distancing never recovers more than 30% of the cost of infection. We also show how the window of opportunity for vaccine development lengthens as the efficiency of social distancing and detection improve

Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV

The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40 inverse picobarns of data collected in pp collisions at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection criteria covering a wide range of physics analysis needs have been examined. For all considered selections, the efficiency to reconstruct and identify a muon with a transverse momentum pT larger than a few GeV is above 95% over the whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4, while the probability to misidentify a hadron as a muon is well below 1%. The efficiency to trigger on single muons with pT above a few GeV is higher than 90% over the full eta range, and typically substantially better. The overall momentum scale is measured to a precision of 0.2% with muons from Z decays. The transverse momentum resolution varies from 1% to 6% depending on pseudorapidity for muons with pT below 100 GeV and, using cosmic rays, it is shown to be better than 10% in the central region up to pT = 1 TeV. Observed distributions of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO

Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum

Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV

The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40 inverse picobarns of data collected in pp collisions at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection criteria covering a wide range of physics analysis needs have been examined. For all considered selections, the efficiency to reconstruct and identify a muon with a transverse momentum pT larger than a few GeV is above 95% over the whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4, while the probability to misidentify a hadron as a muon is well below 1%. The efficiency to trigger on single muons with pT above a few GeV is higher than 90% over the full eta range, and typically substantially better. The overall momentum scale is measured to a precision of 0.2% with muons from Z decays. The transverse momentum resolution varies from 1% to 6% depending on pseudorapidity for muons with pT below 100 GeV and, using cosmic rays, it is shown to be better than 10% in the central region up to pT = 1 TeV. Observed distributions of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO