Multicenter Evaluation of the Simplexa VZV Direct Assay for Detection of Varicella-Zoster Virus in Cerebrospinal Fluid and Lesion-Swab Specimens.

Varicella-zoster virus (VZV) is the etiologic agent of varicella (chickenpox) and herpes zoster (shingles) infections commonly involving skin, mucous membranes, and less frequently the central nervous system. Traditional methods for the laboratory diagnosis of these infections are time-consuming, labor-intensive, and often insensitive. As such, these tests are being replaced by more sensitive and rapid molecular methods. This study evaluated the performance of two different molecular assays, the Simplexa VZV Direct and Simplexa VZV Swab Direct, to detect VZV DNA in cerebrospinal fluid (CSF) and lesion-swab specimens, respectively. The Simplexa VZV Direct and Simplexa VZV Swab Direct assays were compared against individual composite reference methods that varied depending on the sample cohort examined. A total of 883 CSF and 452 cutaneous and mucocutaneous prospective, retrospective, and contrived specimens were evaluated in this multicenter study. The results of this study showed that the Simplexa assays demonstrated near perfect agreement (k = 0.98) compared to the composite reference methods for the detection of VZV in CSF and lesion swab specimens. A further comparison between the standard of care molecular assays employed at the site of specimen collection and the Simplexa assays demonstrated excellent agreement (k = 1.0). The Simplexa assays offer rapid and reliable alternatives for the detection of VZV in certain clinical specimens without the need for nucleic acid extraction.

Evaluation of Oxacillin and Cefoxitin Disk Diffusion and MIC Breakpoints Established by the Clinical and Laboratory Standards Institute for Detection of mecA-Mediated Oxacillin Resistance in Staphylococcus schleiferi.

Staphylococcus schleiferi is a beta-hemolytic, coagulase-variable colonizer of small animals that can cause opportunistic infections in humans. In veterinary isolates, the rate of mecA-mediated oxacillin resistance is significant, with reported resistance rates of >39%. The goal of this study was to evaluate oxacillin and cefoxitin disk diffusion (DD) and MIC breakpoints for detection of mecA-mediated oxacillin resistance in 52 human and 38 veterinary isolates of S. schleiferi Isolates were tested on multiple brands of commercial media and according to Clinical and Laboratory Standards Institute (CLSI) methods. Zone diameters and MIC values were interpreted using CLSI breakpoints (CLSI, Performance Standards for Antimicrobial Susceptibility Testing. M100-S27, 2017) for Staphylococcus aureus/Staphylococcus lugdunensis, coagulase-negative staphylococci (CoNS), and Staphylococcus pseudintermedius Results were compared to those of mecA PCR. Twenty-nine of 90 (32%) isolates were mecA positive. Oxacillin inhibition zone sizes and MICs interpreted by S. pseudintermedius breakpoints reliably differentiated mecA-positive and mecA-negative isolates, with a categorical agreement (CA) of 100% and no very major errors (VMEs) or major errors (MEs) for all media. For cefoxitin DD results interpreted using S. aureus/S. lugdunensis and CoNS breakpoints, CA values were 85% and 75%, respectively, and there were 72% and 64% VMEs, respectively, and 0 MEs. For cefoxitin MICs interpreted using S. aureus/S. lugdunensis breakpoints, CA was 81%, and there were 60% VMEs and no MEs. Our data demonstrate that oxacillin DD or MIC testing methods using the current S. pseudintermedius breakpoints reliably identify mecA-mediated oxacillin resistance in S. schleiferi, while cefoxitin DD and MIC testing methods perform poorly.

A molecular technique to explore the relationship between Porphyromonas gingivalis and severity of chronic periodontitis: A clinical approach.

Relationship between clinical severities of periodontal disease and the expression of the associated pathogens serve as good indicators of real time disease activity and progression. A double blind study using Image J software carried out to assess the density of the amplified band for Porphyromonas gingivalis in periodontally healthy and disease subjects. Results on image densities of P. gingivalis showed a statistical significance (p < 0.005) between healthy and diseased subjects and also within the various groups of periodontal disease severity. Thus, assessment of relative gel image density can be a simple yet valuable tool to monitor real time periodontal disease activity.

Effect of Ablation Rate on the Microstructure and Electrochromic Properties of Pulsed-Laser-Deposited Molybdenum Oxide Thin Films.

Molybdenum trioxide (MoO3) is a well-known electrochromic material. In the present work, n-type α-MoO3 thin films with both direct and indirect band gaps were fabricated by varying the laser repetition (ablation) rate in a pulsed laser deposition (PLD) system at a constant reactive O2 pressure. The electrochromic properties of the films are compared and correlated to the microstructure and molecular-level coordination. Mixed amorphous and textured crystallites evolve at the microstructural level. At the molecular level, using NMR and EPR, we show that the change in the repetition rate results in a variation of the molybdenum coordination with oxygen: at low repetition rates (2 Hz), the larger the octahedral coordination, and greater the texture, whereas at 10 Hz, tetrahedral coordination is significant. The anion vacancies also introduce a large density of defect states into the band gap, as evidenced by XPS studies of the valence band and supported by DFT calculations. The electrochromic contrast improved remarkably by almost 100% at higher repetition rates whereas the switching speed decreased by almost 6-fold. Although the electrochromic contrast and coloration efficiency were better at higher repetition rates, the switching speed, reversibility, and stability were better at low repetition rates. This difference in the electrochromic properties of the two MoO3 films is attributed to the variation in the defect and molecular coordination states of the Mo cation.

Excitation-dependent local symmetry reversal in single host lattice Ba2A(BO3)2:Eu3+ [A = Mg and Ca] phosphors with tunable emission colours.

Eu3+ activated phosphors are widely used as red emitters in various display devices and light emitting diodes (LEDs). The emission characteristics of Eu3+ depend on the local site symmetry. The present study demonstrates the role of excitation-dependent local symmetry changes due to the structural reorganization on the emission colour tuning of Eu3+ from orange-red to orange in single host lattices, Ba2Mg(BO3)2 and Ba2Ca(BO3)2. The choice of these lattices was based on the difference in the extent of strain experienced by the oxygen atoms. The samples with Eu3+ at Ba or Mg (Ca) sites were synthesized using the conventional high-temperature solid-state reaction method. The samples were characterized using powder XRD, 11B MAS-NMR, FT-IR, and diffuse reflectance UV-Vis spectroscopic techniques. The room temperature photoluminescence (PL) recorded using different excitation wavelengths revealed a clear difference in the PL emission features due to symmetry reversal from non-inversion to inversion symmetry around Eu3+. The reorganization of highly strained oxygen atoms leads to such symmetry reversal. First-principles calculations were used to deduce the optimized structures of the two borate host lattices, and local geometries and their distortions upon Eu3+ substitution. The outcomes of these calculations support the experimental findings.

Dissipation kinetics of beta-cyfluthrin and imidacloprid in tea and their transfer from processed tea to infusion.

Dissipation kinetics of mixed formulation consisting beta-cyfluthrin and imidacloprid in tea crop under an open field ecosystem was investigated. The mixed formulation was applied on tea plant at recommended (27 + 63) and double the recommended (54 + 126g a.i./ha) dose and residues were determined using gas chromatography-electron capture detector and high performance liquid chromatography-photodiode array detector for beta-cyfluthrin and imidacloprid, respectively. The limit of quantification of analytical method was 0.05µg/g and the average recoveries were ranged from 88.36% to 103.49% with relative standard deviations of less than 6% at three spiked levels. The experimental results showed that in the green tea leaves imidacloprid dissipated faster than beta-cyfluthrin with the half-life ranging between 1.20-1.39 and 2.89-3.15days, respectively. The beta-cyfluthrin residues present in the processed tea not transferred into the tea infusion during the infusion process and imidacloprid transferred in the range 43.12-49.7%. On the basis of the transfer of residues from processed tea to infusion, a waiting period of 17 days for tea plucking after pesticide application at recommended dose may be suggested.

Deceased Donor Organs: What Can Be Done to Raise Donation Rates Using Evidence From Malaysia?

Organ donation rates have continued to fall seriously short of needs worldwide, with the lowest rates recorded among developing economies. This study seeks to analyze evidence from a developing economy to explore the usefulness of social psychological theory to solve the problem. The study deployed a large survey (n = 10 412) using a convenience sampling procedure targeted at increasing the number of Malaysians registered with the Ministry of Health, Malaysia who are willing to donate organs upon death. Structural equation modeling was deployed to estimate simultaneously the relative influence of cognitive and noncognitive variables on willingness to donate deceased organs. The cognitive factors of donation perception, socioeconomic status and financial incentives, and the noncognitive factors of demography and fear showed a high statistically significant (1%) relationship with willingness to donate organs after death. While financial incentives were significant, cash rewards showed the least impact. Donation perception showed the highest impact, which shows that the development of effective pedagogic programs with simultaneous improvements to the quality of services provided by medical personnel engaged in retrieving and transplanting deceased donor organs can help raise organ donation rates.

Early Changes in Brain Oxygen Tension May Predict Outcome Following Severe Traumatic Brain Injury.

We report on the change in brain oxygen tension (PbtO2) over the first 24 h of monitoring in a series of 25 patients with severe traumatic brain injury (TBI) and relate this to outcome. The trend in PbtO2 for the whole group was to increase with time (mean PbtO2 17.4 [1.75] vs 24.7 [1.60] mmHg, first- vs last-hour data, respectively; p = 0.002). However, a significant increase in PbtO2 occurred in only 17 patients (68 %), all surviving to intensive care unit discharge (p = 0.006). Similarly, a consistent increase in PbtO2 with time occurred in only 13 patients, the correlation coefficient for PbtO2 versus time being ≥0.5 for all survivors. There were eight survivors and four non-survivors, with low correlation coefficients (<0.5). Significantly more patients with a correlation coefficient ≥0.5 for PbtO2 versus time survived in intensive care (p = 0.039). The cumulative length of time that PbtO2 was <20 mmHg was not significantly different among these three groups. In conclusion, although for the cohort as a whole PbtO2 increased over the first 24 h, the individual trends of PbtO2 were related to outcome. There was a significant association between improving PbtO2 and survival, despite these patients having cumulative durations of hypoxia similar to those of non-survivors.

Multifocal Tuberculosis.

Multifocal Tuberculosis represents the many faces of an age old disease. It is characterized by the presence of large multifocal tuberculous areas in same or different organs. A 50 year old male patient, presented with features suggestive of renal failure, low grade fever and cough with mucoid expectoration. He was found to have pulmonary TB, genitourinary TB and tuberculous lymphadenitis. He was started on antituberculous treatment to which he showed good response.

Clinical and antimicrobial efficacy of a controlled-release device containing chlorhexidine in the treatment of chronic periodontitis.

A controlled-release device (CRD) containing chlorhexidine gluconate, such as PerioCol(™)CG (Eucare Pharmaceuticals Pvt. Ltd,, Chennai, India), for subgingival application has little reported data with clinical as well as antimicrobial efficacy. This study evaluated clinical and subgingival microbial changes on using indigenously developed PerioCol™CG as an adjunct to scaling and root planing (SRP) in the treatment of chronic periodontitis. Forty posterior first molar sites having probing pocket depth ≥ 5 mm were selected and divided into two groups, with 20 sites in each group, in a split-mouth design. Group A (test site) was treated with SRP and PerioCol(™)CG, while group B (control site) was treated with SRP alone. Subgingival microbial samples were collected at baseline and 1 month after the initial SRP, while probing depth (PD), clinical attachment level (CAL) and gingival index (GI) were recorded at baseline, after 1 month and after 3 months. Microbial detection of Porphyromonas gingivalis (P. gingivalis) and Tannerella forsythia (T. forsythia) was done by means of polymerase chain reaction (PCR). A significant improvement was observed in all clinical measures in sites treated with PerioCol(™)CG as compared to the control sites during the study period. Also, there was a statistically significant reduction in the proportion of occurrence of P. gingivalis and T. forsythia after intervention in test sites as compared to control sites. Our data suggest that SRP combined with subgingival administration of PerioCol™CG has a significantly better and prolonged effect compared to SRP alone on the PD, clinical attachment loss and elimination of periodontopathogens.

The role of encapsulation by ß-cyclodextrin in the interaction of raloxifene with macromolecular targets: a study by spectroscopy and molecular modeling.

We report the binding of the drug raloxifene with Calf thymus DNA (ctDNA) and bovine serum albumin (BSA) in the presence and absence of ß-cyclodextrin (ß-CD) and explain the influence of ß-cyclodextrin on the binding of the drug to macromolecules. UV-Vis absorption, fluorescence, proton nuclear magnetic resonance and two-dimensional rotating-frame nuclear overhauser effect spectroscopic techniques are used to study the stoichiometry and the binding strength of the complexes. Molecular modeling is used in combination with other techniques to propose the structure of the inclusion complex and the interaction with ctDNA. The Stern-Volmer quenching constants of the interaction of raloxifene with ctDNA in aqueous and in ß-CD solution are compared. The competition for binding of ctDNA with raloxifene and Methylene Blue is studied. The apparent binding constant and the number of binding sites for the binding of raloxifene with BSA in aqueous solution are significantly different from those in the presence of ß-CD. The influence of ß-CD on the binding of the small molecules with biological macromolecules is discussed. We infer that the binding strengths between raloxifene and macromolecules, viz., ctDNA and BSA are influenced by the ß-CD encapsulation. These results may suggest new ways to tune the drug binding to biomacromolecules by encapsulating specific moieties of drugs.

Persistence and dissipation of flubendiamide and its risk assessment on gherkin (Cucumis sativus L.).

A supervised open field trial was conducted to evaluate the dissipation pattern and risk assessment of flubendiamide in gherkin fruits following foliar application of Fame 480 SC at 60 and 120 g a.i. ha(-1). Samples of gherkin fruits were drawn at different time intervals and quantified by HPLC-DAD. The maximum initial deposits of flubendiamide on gherkin were found to be 0.79 and 1.52 mg kg(-1), respectively, at recommended and double the recommended doses. The dissipation pattern of flubendiamide followed a first-order kinetics with half-lives of 1.87 to 2.16 days at 60 and 120 g a.i. ha(-1), respectively. The limit of quantification of flubendiamide and desiodo flubendiamide was observed to be 0.01 mg kg(-1) for gherkin fruit and soil substrates. Theoretical maximum residue contribution (TMRC) for flubendiamide was calculated and found to be well below the maximum permissible intake (MPI) on gherkin fruits. Thus, the application of flubendiamide at the recommended dose on gherkin fruits presents no human health risks and safe to consumers.

Bioanalytical method development, validation and quantification of dorsomorphin in rat plasma by LC-MS/MS.

The present investigation describes the development and validation of a sensitive liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) method for the estimation of dorsomorphin in rat plasma. A sensitive LC-MS/MS method was developed using multiple reaction monitoring mode, with the transition of m/z (Q1/Q3) 400.2/289.3 for dorsomorphin and m/z (Q1/Q3) 306.2/236.3 for zaleplon. Chromatographic separation was achieved on a reverse phase Agilent XDB C18 column (100 × 4.6 mm, 5 µm). The mobile phase consisted of acetonitrile and 5 mm ammonium acetate buffer (pH 6.0) 90:10 v/v, at a flow rate of 0.8 mL/min. The effluence was ionized in positive ion mode by electrospray ionization (ESI) and quantitated by mass spectrometry. The retention times of dorsomorphin and internal standard were found to be 2.13 and 1.13 min, respectively. Mean extraction recovery of dorsomorphin and internal standard in rat plasma was above 80%. Dorsomorphin calibration curve in rat plasma was linear (r(2) ≥ 0.99) ranging from 0.005 to 10 µg/mL. Inter-day and intra-day precision and accuracy were found to be within 85-115% (coefficient of variation). This method was successfully applied for evaluation of the oral pharmacokinetic profile of dorsomorphin in male Wistar rats.

Dynamics and residues of mixed formulation of fenamidone and mancozeb in gherkin field ecosystem.

The dynamics and residues of mixed formulation of fenamidone and mancozeb in a gherkin field ecosystem were investigated. The quantification was performed using gas chromatography-electron capture detection (GC-ECD) and UV-vis spectrophotometry for fenamidone and mancozeb residues, respectively. The method was validated using blank samples spiked at three levels and the results showed that recoveries ranged from 92 to 98 and 90 to 96 percent with relative standard deviations (RSD) ranging of 0.78-5.9 and 2.04-4.41 percent for fenamidone and mancozeb, respectively. The compound degradation followed a first order kinetics with half-lives of 2.8-2.82 and 2.02-2.26 days, for fenamidone and mancozeb, respectively. Pesticide residues in fruit were below the EU maximum residue level (MRL) after 10 days for fenamidone (0.02 µg/g) and just after treatment for mancozeb (2 µg/g). These results can be utilized in formulating the spray schedule and safety evaluation for these pesticides in gherkin.

Application of an electro elution system for direct purification of linear covalently closed DNA fragments.

Gene therapy is a powerful treatment modality. Non-viral gene therapy vectors power one arm of this important approach, due to their enhanced safety profile compared to their viral counterparts. New non-viral approaches continue to be developed, but purification can bottleneck the scaleup and cost-effectiveness and quality of some of these advanced vectors. We require more advanced purification and separation techniques compared to conventional methods to maximize resolution in a scalable manner. The Prep Cell system is a continuous electro elution system that contains a circular gel casting tube where DNA mixtures can be run through and subsequently migrate into an elution chamber, to be eluted by a peristaltic pump. This DNA separation and purification process confers advantages over other conventional methods, including i) the elimination of multiple downstream purification process requirements; ii) its ability to be applied in mid-scale settings, and iii), its high-resolution power. In this study, we assessed the ability of this Prep Cell Model 491 system to purify a novel type of non-viral linear covalently closed (LCC) DNA minivector (ministring DNA) from its precursor parent plasmid DNA and process by-product DNA species by analyzing for effective separation via agarose gel electrophoresis, recovery yield, single enzyme digestion, and quality control assessments. Overall, effective separation and resolution of mini-DNA vectors was obtained using the Prep Cell system, conferring its potential to be applied towards mid-scale purification of DNA vectors for a variety of research, and eventually, clinical applications.

Multiresidue analysis of organochlorine pesticides in milk, egg and meat by GC-ECD and confirmation by GC-MS.

A multiresidue method was developed and optimized for the quantification of organochlorine pesticides (OCPs) in milk, egg and meat samples. Sample extraction was performed by adopting QuEChERS principle and the extracts were cleaned-up dispersive solid-phase extraction with primary secondary amine after salting out with NaCl and MgSO(4). Analysis was carried out by gas chromatography coupled with electron capture detector and confirmation by gas chromatography-mass spectrometry. The performance of the method was investigated in terms of linearity, accuracy, precision, detection limit and quantification limit (LOQ). Good linearity was obtained, with correlation coefficients (r(2)) higher than 0.992. Mean recoveries were found in the ranges 72%-108%, 74%-101% and 75.27%-104.56% for the milk, egg and meat, respectively, RSD % turned out to range from 0.28% to 10.05%. The method developed was successfully tested on commercial milk, egg, and meat samples from the markets of Tamil Nadu (India), proving to be a useful tool in routine analysis of OCPs for monitoring purposes. None of the compounds of interest were observed above their respective LOQ.

Persistence behaviour of thiacloprid residues in/on green tea leaves, processed tea and tea infusion.

Thiacloprid residues were estimated in green tea leaves, processed tea and tea infusion by HPLC-Diode Array detection. The average initial deposits of thiacloprid (Alanto 240 SC) on the green tea leaves were found to be 3.72 and 6.77 µg g(-1) at single and double doses, respectively. The results showed that thiacloprid dissipated faster in green tea leaves following a first order reaction kinetics at both application rates. The amount of dissipation in 14 days was 93.37% and 91.62% for single and double doses respectively. Half life (T(1/2)) for degradation of thiacloprid in green tea leaves were observed to be 3.34 and 3.58 days at single and double doses respectively. Thiacloprid residues in processed tea ranged from 0.16 to 0.63 µg g(-1) on seventh day and no residues could be detected on 14th day at single dose. Infusion study indicated that thiacloprid did not infuse into tea liquor from processed tea. The limit of determination was found to be 0.05 µg g(-1).

Chromosome length ratio as a biomarker of DNA damage in cells exposed to high dose ionizing radiation.

The premature chromosome condensation (PCC) assay is considered as complementary bio-dosimetry tool for chromosome aberration assay and the PCC assay can be used to estimate high dose exposure. Though the PCC ring is considered as prospective biomarker, chromosome length ratio (ratio of longest and shortest chromosome length in PCC spreads) of chemically induced PCC is shown to be very good indicator of ionizing radiation. In view of this, an in-vitro study has been performed using PCC assay to suggest chromosome length ratio (LR) as potential bio-dosimeter induced by high dose ionizing radiation. Blood samples were collected from healthy subjects (n = 3) after prior consent and irradiated to ten different doses ranging between 0 and 20 Gy using 6 MV LINAC X-rays with dose rate of 5.6 Gy/min. Irradiated lymphocytes were cultured and calyculin induced PCC spreads were prepared. PCC spreads were captured using image analysis system and chromosome lengths were measured using open-source ImageJ software. For each dose, LR for 50 chromosome spreads were computed and mean LR value was calculated. LR varies between 6.0 ± 0.08 and 23.6 ± 0.55 for the dose range between 2 and 20 Gy. The dose response curve for LR was observed to be linear with y = 1.02x + 3.36, R2 = 0.97. Linear dose response relationship obtained in the present study confirms the prospective use of LR measurement. This study is first of its kind to examine chromosome length ratio as a biomarker of DNA damage in cells exposed to high dose X-ray exposure.

Development of a numerical model for sector-average plume gamma dose and its validation with dose rate measurements at Kalpakkam NPP site, India.

A Gaussian Plume based simple numerical model, named DIFFUSE is developed to simulate the long-term sector-average plume gamma dose due to radioactive plume released during normal operation of nuclear facilities. DIFFUSE calculates site specific joint frequency distributions of wind speed, wind direction and atmospheric stability using micrometeorological observations. It performs the finite sector-average dose integration for any stack height and gamma energy using Simpson's 1/3rd method with sufficient computational efficiency within the site boundary up to 2 km. Plume dose contribution to the main plume sector from nearest and next nearest side plume sectors is also calculated. DIFFUSE is validated with a 3-month long, starting from February 2021 to April 2021, dose rate observation data during operational releases from 100 m stack of Madras Atomic Power Station, Kalpakkam, India. Meteorological data from onsite 50 m tower and continuous dose rate observation from two sets of Autonomous Gamma Dose Logger (AGDL) detectors, namely n-AGDLs and r-AGDLs, placed in two different configurations along the geometric arcs of wind sectors around the stack are used. Simulated doses are compared with look-up table based dose estimates by Hukkoo et al. (1988). Linear spatial averaging of cumulative AGDL doses on a sector arc is used as measured sector-average dose for model validation. Simulations performed for both n-AGDL and r-AGDL configurations show DIFFUSE estimated doses are ∼37% lower and Hukkoo estimated doses are at least ∼50% lower than the measured doses. Statistical analysis of DIFFUSE simulated doses shows a statistical correlation of R2∼98.3%, slope of the fit ∼1.36 for n-AGDL setup and R2∼75.3%, slope of the fit ∼1.57 for r-AGDL setup. Overall, DIFFUSE produces conservative doses compared to look-up table based doses as required by regulatory bodies.