Bio-mimetic selectivity in Hg2+ sensing developed via electro-copolymerized PEDOT and benzothiazole-Au nanoparticles composite.

To eliminate the potential health risks of mercury, development of stable and selective mercury sensor with high sensitivity is the need of the hour. To address this, a novel PEDOT-AA-BTZ-Au-based Hg2+ selective, hybrid electrochemical sensor has been designed by following a simple protocol for electrode fabrication. The electrode was designed by carefully optimizing the onset oxidation potential of supramolecule 2-(anthracen-9-yl)benzo[d]thiazole (AA-BTZ) and conducting polymer poly-(3,4-ethylenedioxythiophene) (PEDOT), using copolymerization approach followed by dropcasting of gold nanoparticles (AuNPs). The designed electrode offered synergistic effects thus augmenting the electrical conductivity and adsorption capacity as depicted by its porous surface morphology. The highly sensitive analytical signal was generated by sulphur pockets present in AA-BTZ and PEDOT conducting framework. This is further complemented by the selectivity offered by the soft interactions between AuNPs and Hg2+ resulting in a low detection limit of 0.60 nM. The prepared system was further utilized for sensing Hg2+ ion in real systems including lake water and cosmetic samples. Low interference from other ions and better reproducibility further established the suitability of the designed transducer system for future on-site sensing.

Structural insights into the amino acid usage variations in the profilin gene family.

Profilin protein is present ubiquitously in all forms of life and is allied with allergic responses among atopic individuals. In addition to this, profilins from various food sources are also associated with IgE cross-reactivity and are thus classified as pan-allergens. The present study unravels the physicochemical basis of differential amino acid usage patterns observed in the profilin gene family. Correspondence analysis based on amino acid usage of allergen and non-allergen profilins revealed discrete clusters among them, signifying differential patterns of amino acid usage. The amino acids, namely methionine, proline, histidine, glutamine, glutamic acid, tryptophan and glycine were found to be more frequently utilised by the allergen profilins compared to the non-allergens. Correlation analysis revealed that physicochemical features like protein disorder, trypsin digestion and solubility differed significantly among the allergen and non-allergen profilins, thus supporting the observations from correspondence analysis. In addition, comprehensive sequence analysis revealed that the allergen profilins possess conserved motifs which may correlate with their distinct physicochemical features. An in-depth structural analysis revealed that the over-represented amino acids in allergen profilins have a propensity of being exposed on the surface, which may be attributed to their distinct allergenic characteristics. The distinguished physicochemical features observed among allergens and non-allergens can be employed as descriptors to develop machine learning-based allergenicity prediction models.

Drug-target binding quantitatively predicts optimal antibiotic dose levels in quinolones.

Antibiotic resistance is rising and we urgently need to gain a better quantitative understanding of how antibiotics act, which in turn would also speed up the development of new antibiotics. Here, we describe a computational model (COMBAT-COmputational Model of Bacterial Antibiotic Target-binding) that can quantitatively predict antibiotic dose-response relationships. Our goal is dual: We address a fundamental biological question and investigate how drug-target binding shapes antibiotic action. We also create a tool that can predict antibiotic efficacy a priori. COMBAT requires measurable biochemical parameters of drug-target interaction and can be directly fitted to time-kill curves. As a proof-of-concept, we first investigate the utility of COMBAT with antibiotics belonging to the widely used quinolone class. COMBAT can predict antibiotic efficacy in clinical isolates for quinolones from drug affinity (R2>0.9). To further challenge our approach, we also do the reverse: estimate the magnitude of changes in drug-target binding based on antibiotic dose-response curves. We overexpress target molecules to infer changes in antibiotic-target binding from changes in antimicrobial efficacy of ciprofloxacin with 92-94% accuracy. To test the generality of our approach, we use the beta-lactam ampicillin to predict target molecule occupancy at MIC from antimicrobial action with 90% accuracy. Finally, we apply COMBAT to predict antibiotic concentrations that can select for resistance due to novel resistance mutations. Using ciprofloxacin and ampicillin as well defined test cases, our work demonstrates that drug-target binding is a major predictor of bacterial responses to antibiotics. This is surprising because antibiotic action involves many additional effects downstream of drug-target binding. In addition, COMBAT provides a framework to inform optimal antibiotic dose levels that maximize efficacy and minimize the rise of resistant mutants.

Environmental survival of SARS-CoV-2 - A solid waste perspective.

The advent of COVID-19 has kept the whole world on their toes. Countries are maximizing their efforts to combat the virus and to minimize the infection. Since infectious microorganisms may be transmitted by variety of routes, respiratory and facial protection is required for those that are usually transmitted via droplets/aerosols. Therefore this pandemic has caused a sudden increase in the demand for personal protective equipment (PPE) such as gloves, masks, and many other important items since, the evidence of individual-to-individual transmission (through respiratory droplets/coughing) and secondary infection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). But the disposal of these personal protective measures remains a huge question mark towards the environmental impact. Huge waste generation demands proper segregation according to waste types, collection, and recycling to minimize the risk of infection spread through aerosols and attempts to implement measures to monitor infections. Hence, this review focuses on the impact of environment due to improper disposal of these personal protective measures and to investigate the safe disposal methods for these protective measures by using the safe, secure and innovative biological methods such as the use of Artificial Intelligence (AI) and Ultraviolet (UV) lights for killing such deadly viruses.

Comparison of in-vitro and in-vivo parameters of whole blood derived random donor platelets (RDP) after over-night hold with RDP prepared after 2-h hold: Single centre report from India.

BACKGROUND: Random Donor Platelet (RDP) derived from whole blood is the major source of platelets in India. At our centre, we prepare RDPs by buffy coat method after a holding period of 2-hours (THRDP) as per current regulatory guidelines. Overnight hold of buffy coats before RDP preparation (OHRDP) would logistically optimise the manpower usage at our centre. The aim of this study was to compare both in-vitro as well as in-vivo parameters of OHRDPs with THRDPs. METHODOLOGY: Hematological (Platelet, leucocyte counts), physical (pH and Swirling) and biochemical parameters (pO2, pCO2, lactate, bicarbonate and glucose) as well as platelet activation markers were tested in THRDPs and OHRDPs each at Day-1 and Day-5 as in-vitro studies. Separately, in-vivo study was done where Corrected count increment (CCI) and percentage platelet recovery (PPR) were considered. All parameters were expressed as Mean ± Standard deviation and were analysed using paired t-test with level of significance, p < 0.05. RESULTS: OHRDPs had higher platelet counts and lower leucocytes and CD62 P expression than THRDPs. All other markers were well within the quality control range in both groups. No significant differences were seen in the two groups when comparing CCI and PPR. CONCLUSION: OHRDPs were found to be as good or better as compared to the THRDPs in the in-vitro part of our study. Additionally, there were no significant differences between the two groups when they were compared in vivo. This makes us conclude that overnight hold of buffy coats may be implemented at our center.

Cellular signalling pathways mediating the pathogenesis of chronic inflammatory respiratory diseases: an update.

Respiratory disorders, especially non-communicable, chronic inflammatory diseases, are amongst the leading causes of mortality and morbidity worldwide. Respiratory diseases involve multiple pulmonary components, including airways and lungs that lead to their abnormal physiological functioning. Several signaling pathways have been reported to play an important role in the pathophysiology of respiratory diseases. These pathways, in addition, become the compounding factors contributing to the clinical outcomes in respiratory diseases. A range of signaling components such as Notch, Hedgehog, Wingless/Wnt, bone morphogenetic proteins, epidermal growth factor and fibroblast growth factor is primarily employed by these pathways in the eventual cascade of events. The different aberrations in such cell-signaling processes trigger the onset of respiratory diseases making the conventional therapeutic modalities ineffective. These challenges have prompted us to explore novel and effective approaches for the prevention and/or treatment of respiratory diseases. In this review, we have attempted to deliberate on the current literature describing the role of major cell signaling pathways in the pathogenesis of pulmonary diseases and discuss promising advances in the field of therapeutics that could lead to novel clinical therapies capable of preventing or reversing pulmonary vascular pathology in such patients.

Evaluation of Different Preosteotomy Determinants as Affecting the Success of Implant Therapy: A "CBCT"-based Clinical Study.

AIM: The success of implant therapy is of greatest concern for clinicians because a minor negligence can lead to ultimate failure of treatment. However, comprehensive and precise treatment planning can ensure high success rate of implant therapy. Cone-beam computed tomography (CBCT) is an innovation that allows clinicians to explore all related factors in details. This study was conducted to evaluate different preosteotomy determinants as affecting the success of implant therapy in the maxillary anterior region using CBCT. MATERIALS AND METHODS: This study was conducted on 98 partially or complete denture patients willing for artificial replacement of their missing teeth by implant or implant over-denture. Demographic details of participating patients were collected. Furthermore, comprehensive local examination was also done to finalize the site of placement of implant. Cone-beam computed tomography was attempted in all patients for determining accurate implant location, status of bone, and other interrelated determinants of implant success. Cone-beam computed tomography was also prescribed for patients so as to have presurgical idea of implant dimensions as shown in virtual placement of implant. To rule out any interobserver bias, the interpretations of CBCT images were completed by two independent experienced observers. RESULTS: In the 98 studied patients, 61 were males and 37 were females. The study was restricted to the maxillary anterior region only. The studied preosteotomy determinants were available bone height and width in the edentulous region from ridge crest up to the maxillary sinus floor or the nasal fossa floor. A total of 107 implants were placed virtually (on CBCT) in the maxillary anterior region and compared quantitatively in postosteotomy phases. Implant placement sites were the maxillary central incisor region (39), the lateral incisor region (31), and canine (37). Authors also noticed that the relative length and width of virtual implant remained unaffected in 97% of the cases. CONCLUSION: Cone-beam computed tomography showed accurate status of various presurgical determinants like trabeculae, peri-ridiculer pathology, and amount of horizontal and vertical bone losses. Hence, it was further concluded that all these presurgical determinants greatly affect the final success rate of implant therapy. It is therefore deemed necessary to judiciously consider and clinically manage such factors before attempting implant in the maxillary anterior region. CLINICAL SIGNIFICANCE: Presurgical evaluation of factors associated with implant dimensions significantly assists clinicians in deciding the finest treatment option. All additional information provided by CBCT genuinely led to a change in the treatment plan that provides enhanced clinical outcome with lesser postoperative complications. How to cite this article: Jain S, Kapoor K, Sethi K, et al. Evaluation of Different Preosteotomy Determinants as Affecting the Success of Implant Therapy: A "CBCT"-based Clinical Study. J Contemp Dent Pract 2019;20(10):1212-1216.

A drag force interpolation model for capsule-shaped cells in fluid flows near a surface.

We report an interpolation model to calculate the hydrodynamic force on tethered capsule-shaped cells in micro-fluidic flows near a surface. Our model is based on numerical solutions of the full Navier-Stokes equations for capsule-shaped objects considering their geometry, aspect ratio and orientation with respect to fluid flow. The model reproduced the results from computational fluid dynamic simulations, with an average error of <0.15 % for objects with an aspect ratio up to 5, and the model exactly reproduced the Goldman approximation of spherical objects close to a surface. We estimated the hydrodynamic force imposed on tethered Escherichia coli cells using the interpolation model and approximate models found in the literature, for example, one that assumes that E. coli is ellipsoid shaped. We fitted the 2D-projected area of a capsule and ellipsoid to segmented E. coli cells. We found that even though an ellipsoidal shape is a reasonable approximation of the cell shape, the capsule gives 4.4 % better agreement, a small difference that corresponds to 15 % difference in hydrodynamic force. In addition, we showed that the new interpolation model provides a significantly better agreement compared to estimates from commonly used models and that it can be used as a fast and accurate substitute for complex and computationally heavy fluid dynamic simulations. This is useful when performing bacterial adhesion experiments in parallel-plate flow channels. We include a MATLAB script that can track cells in a video time-series and estimate the hydrodynamic force using our interpolation formula.

Fluorescent Sensing Assay for Trinitrotoluene Using Fluorescein Isothiocyanate Conjugated Mesoporous MCM-41 Particles.

In the present study, Trinitrotoluene (TNT) has been detected by the formation of Meisenheimer complex using Fluorescein isothiocyanate (FITC) dye loaded Mesoporous silica particles (MCM-41). FITC dye loaded mesoporous silica particles (MCM-41/FITC) have been synthesized using (3-Aminopropyl)trimethoxysilane, APTMS (λex = 490 nm and λem = 512 nm). TNT forms Meisenheimer complex with the amine group of APTMS present on MCM-41 particles. The loading of FITC in the pores of MCM-41 particles has been confirmed by different advanced characterization techniques. The average diameter of mesoporous MCM-41 particles was found about 130 nm. Pore volume is observed to decrease from 1.06 cm3/g to 0.49 cm3/g after FITC loading. The selective detection of TNT up to 0.1 ppb level makes MCM-41/FITC particles a potential sensing material for TNT detection.

Antibodies Damage the Resilience of Fimbriae, Causing Them To Be Stiff and Tangled.

As adhesion fimbriae are a major virulence factor for many pathogenic Gram-negative bacteria, they are also potential targets for antibodies. Fimbriae are commonly required for initiating the colonization that leads to disease, and their success as adhesion organelles lies in their ability to both initiate and sustain bacterial attachment to epithelial cells. The ability of fimbriae to unwind and rewind their helical filaments presumably reduces their detachment from tissue surfaces with the shear forces that accompany significant fluid flow. Therefore, the disruption of functional fimbriae by inhibiting this resilience should have high potential for use as a vaccine to prevent disease. In this study, we show that two characteristic biomechanical features of fimbrial resilience, namely, the extension force and the extension length, are significantly altered by the binding of antibodies to fimbriae. The fimbriae that were studied are normally expressed on enterotoxigenic Escherichia coli, which are a major cause of diarrheal disease. This alteration in biomechanical properties was observed with bivalent polyclonal antifimbrial antibodies that recognize major pilin subunits but not with the Fab fragments of these antibodies. Thus, we propose that the mechanism by which bound antibodies disrupt the uncoiling of natural fimbria under force is by clamping together layers of the helical filament, thereby increasing their stiffness and reducing their resilience during fluid flow. In addition, we propose that antibodies tangle fimbriae via bivalent binding, i.e., by binding to two individual fimbriae and linking them together. Use of antibodies to disrupt physical properties of fimbriae may be generally applicable to the large number of Gram-negative bacteria that rely on these surface-adhesion molecules as an essential virulence factor. IMPORTANCE: Our study shows that the resiliency of colonization factor antigen I (CFA/I) and coli surface antigen 2 (CS2) fimbriae, which are current targets for vaccine development, can be compromised significantly in the presence of antifimbrial antibodies. It is unclear how the humoral immune system specifically interrupts infection after the attachment of enterotoxigenic Escherichia coli (ETEC) to the epithelial surface. Our study indicates that immunoglobulins, in addition to their well-documented role in adaptive immunity, can mechanically damage the resilience of fimbriae of surface-attached ETEC, thereby revealing a new mode of action. Our data suggest a mechanism whereby antibodies coat adherent and free-floating bacteria to impede fimbrial resilience. Further elucidation of this possible mechanism is likely to inform the development and refinement of preventive vaccines against ETEC diarrhea.

Structure and function of enterotoxigenic Escherichia coli fimbriae from differing assembly pathways.

Pathogenic enterotoxigenic Escherichia coli (ETEC) are the major bacterial cause of diarrhea in young children in developing countries and in travelers, causing significant mortality in children. Adhesive fimbriae are a prime virulence factor for ETEC, initiating colonization of the small intestinal epithelium. Similar to other Gram-negative bacteria, ETEC express one or more diverse fimbriae, some assembled by the chaperone-usher pathway and others by the alternate chaperone pathway. Here, we elucidate structural and biophysical aspects and adaptations of each fimbrial type to its respective host niche. CS20 fimbriae are compared with colonization factor antigen I (CFA/I) fimbriae, which are two ETEC fimbriae assembled via different pathways, and with P-fimbriae from uropathogenic E. coli. Many fimbriae unwind from their native helical filament to an extended linear conformation under force, thereby sustaining adhesion by reducing load at the point of contact between the bacterium and the target cell. CFA/I fimbriae require the least force to unwind, followed by CS20 fimbriae and then P-fimbriae, which require the highest unwinding force. We conclude from our electron microscopy reconstructions, modeling and force spectroscopy data that the target niche plays a central role in the biophysical properties of fimbriae that are critical for bacterial pathophysiology.

Detecting Bacterial Surface Organelles on Single Cells Using Optical Tweezers.

Bacterial cells display a diverse array of surface organelles that are important for a range of processes such as intercellular communication, motility and adhesion leading to biofilm formation, infections, and bacterial spread. More specifically, attachment to host cells by Gram-negative bacteria are mediated by adhesion pili, which are nanometers wide and micrometers long fibrous organelles. Since these pili are significantly thinner than the wavelength of visible light, they cannot be detected using standard light microscopy techniques. At present, there is no fast and simple method available to investigate if a single cell expresses pili while keeping the cell alive for further studies. In this study, we present a method to determine the presence of pili on a single bacterium. The protocol involves imaging the bacterium to measure its size, followed by predicting the fluid drag based on its size using an analytical model, and thereafter oscillating the sample while a single bacterium is trapped by an optical tweezer to measure its effective fluid drag. Comparison between the predicted and the measured fluid drag thereby indicate the presence of pili. Herein, we verify the method using polymer coated silica microspheres and Escherichia coli bacteria expressing adhesion pili. Our protocol can in real time and within seconds assist single cell studies by distinguishing between piliated and nonpiliated bacteria.

Biomechanical and structural features of CS2 fimbriae of enterotoxigenic Escherichia coli.

Enterotoxigenic Escherichia coli (ETEC) are a major cause of diarrhea worldwide, and infection of children in under-developed countries often leads to high mortality rates. Isolated ETEC expresses a plethora of colonization factors (fimbriae/pili), of which CFA/I and CFA/II, which are assembled via the alternate chaperone pathway (ACP), are among the most common. Fimbriae are filamentous structures whose shafts are primarily composed of helically arranged single pilin-protein subunits, with a unique biomechanical ability to unwind and rewind. A sustained ETEC infection, under adverse conditions of dynamic shear forces, is primarily attributed to this biomechanical feature of ETEC fimbriae. Recent understanding about the role of fimbriae as virulence factors points to an evolutionary adaptation of their structural and biomechanical features. In this work, we investigated the biophysical properties of CS2 fimbriae from the CFA/II group. Homology modeling of its major structural subunit, CotA, reveals structural clues related to the niche in which they are expressed. Using optical-tweezers force spectroscopy, we found that CS2 fimbriae unwind at a constant force of 10 pN and have a corner velocity (i.e., the velocity at which the force required for unwinding rises exponentially with increased speed) of 1300 nm/s. The biophysical properties of CS2 fimbriae assessed in this work classify them into a low-force unwinding group of fimbriae together with the CFA/I and CS20 fimbriae expressed by ETEC strains. The three fimbriae are expressed by ETEC, colonize in similar gut environments, and exhibit similar biophysical features, but differ in their biogenesis. Our observation suggests that the environment has a strong impact on the biophysical characteristics of fimbriae expressed by ETEC.

Organization of ribosomes and nucleoids in Escherichia coli cells during growth and in quiescence.

We have examined the distribution of ribosomes and nucleoids in live Escherichia coli cells under conditions of growth, division, and in quiescence. In exponentially growing cells translating ribosomes are interspersed among and around the nucleoid lobes, appearing as alternative bands under a fluorescence microscope. In contrast, inactive ribosomes either in stationary phase or after treatment with translation inhibitors such as chloramphenicol, tetracycline, and streptomycin gather predominantly at the cell poles and boundaries with concomitant compaction of the nucleoid. However, under all conditions, spatial segregation of the ribosomes and the nucleoids is well maintained. In dividing cells, ribosomes accumulate on both sides of the FtsZ ring at the mid cell. However, the distribution of the ribosomes among the new daughter cells is often unequal. Both the shape of the nucleoid and the pattern of ribosome distribution are also modified when the cells are exposed to rifampicin (transcription inhibitor), nalidixic acid (gyrase inhibitor), or A22 (MreB-cytoskeleton disruptor). Thus we conclude that the intracellular organization of the ribosomes and the nucleoids in bacteria are dynamic and critically dependent on cellular growth processes (replication, transcription, and translation) as well as on the integrity of the MreB cytoskeleton.

Asymmetric growth and division in Mycobacterium spp.: compensatory mechanisms for non-medial septa.

Mycobacterium spp., rod-shaped cells belonging to the phylum Actinomycetes, lack the Min- and Noc/Slm systems responsible for preventing the placement of division sites at the poles or over the nucleoids to ensure septal assembly at mid-cell. We show that the position for establishment of the FtsZ-ring in exponentially growing Mycobacterium marinum and Mycobacterium smegmatis cells is nearly random, and that the cells often divide non-medially, producing two unequal but viable daughters. Septal sites and cellular growth disclosed by staining with the membrane-specific dye FM4-64 and fluorescent antibiotic vancomycin (FL-Vanco), respectively, showed that many division sites were off-centre, often over the nucleoids, and that apical cell growth was frequently unequal at the two poles. DNA transfer through the division septum was detected, and translocation activity was supported by the presence of a putative mycobacterial DNA translocase (MSMEG2690) at the majority of the division sites. Time-lapse imaging of single live cells through several generations confirmed both acentric division site placement and unequal polar growth in mycobacteria. Our evidence suggests that post-septal DNA transport and unequal polar growth may compensate for the non-medial division site placement in Mycobacterium spp.

Antimicrobial liposomes-in-nanofiber wound dressings prepared by a green and sustainable wire-electrospinning set-up.

Increasing prevalence of infected and chronic wounds demands improved therapy options. In this work an electrospun nanofiber dressing with liposomes is suggested, focusing on the dressing's ability to support tissue regeneration and infection control. Chloramphenicol (CAM) was the chosen antibiotic, added to the nanofibers after first embedded in liposomes to maintain a sustained drug release. Nanofibers spun from five different polymer blends were tested, where pectin and polyethylene oxide (PEO) was identified as the most promising polymer blend, showing superior fiber formation and tensile strength. The wire-electrospinning setup (WES) was selected for its pilot-scale features, and water was applied as the only solvent for green electrospinning and to allow direct liposome incorporation. CAM-liposomes were added to Pectin-PEO nanofibers in the next step. Confocal imaging of rhodamine-labelled liposomes indicated intact liposomes in the fibers after electrospinning. This was supported by the observed in vitroCAM-release, showing that Pectin-PEO-nanofibers with CAM-liposomes had a delayed drug release compared to controls. Biological testing confirmed the antimicrobial efficacy of CAM and good biocompatibility of all CAM-nanofibers. The successful fiber formation and green production process with WES gives a promising outlook for industrial upscaling.

The pesticide thiamethoxam induced toxicity in Brassica juncea and its detoxification by Pseudomonas putida through biochemical and molecular modifications.

Insecticides are extensively exploited by humans to destroy the pests one such compound thiamethoxam is widely used over crops to offer control over wide-array of sucking insect pests. The present study unravels the detoxification potential of Pseudomonas putida in thiamethoxam exposed B. juncea seedlings. The thiamethoxam application curtailed the fresh weight, dry weight and seedling length by 106.22%, 80.29% and 116.78% while P. putida revived these growth parameters in thiamethoxam exposed B. juncea seedlings by 59.65%, 72.99% and 164.56% respectively. The exogenous supplementation of P. putida resuscitated the photosynthetic efficiency of B. juncea seedlings exposed to thiamethoxam as total chlorophyll, chlorophyll a, chlorophyll b, carotenoid, flavonoid and anthocyanin contents were enhanced by 169.42%, 62.90%, 72.89%, 78.53%, 47.36% and 515.15% respectively in contrast to TMX exposed seedlings. Further, P. putida pre-treatment reinvigorated the osmoprotectant content in B. juncea seedlings grown in thiamethoxam as trehalose, glycine betaine and proline contents were thrusted by 21.20%, 58.98% and 34.26% respectively. The thiamethoxam exposure exorbitated the superoxide anion, hydrogen peroxide and MDA levels by 223.03%, 130.18% and 74.63% while P. putida supplementation slackened these oxidative burst levels by 41.75%, 3.79% and 29.09% respectively in thiamethoxam treated seedlings. Notably, P. putida inoculation in thiamethoxam exposed seedlings upregulated the enzymatic antioxidant and non-enzymatic antioxidant activities as SOD, CAT and glutathione were enhanced by 163.76%, 99.29% and 114.91% respectively in contrast to thiamethoxam treated seedlings. The gene expression analysis exhibited the negative impact of thiamethoxam on B. juncea seedlings as conferred by upregulation of chlorophyllase by 443.86 folds whereas P. putida application in thiamethoxam exposed seedlings downregulated the chlorophyllase expression by 248.73 folds and upregulated CXE, GST, NADH and POD genes by 0.44, 4.07, 1.43 and 0.98 folds respectively suggesting the molecular-level thiamethoxam detoxification efficiency of P. putida.

Raloxifene, a SERM targets PD-L1: an in-silico study.

OBJECTIVES: Immunotherapeutic interventions in cancer have been considerably successful and widely accepted for cancer treatment, but are costly and cannot be afforded by all patients. Because of the high cost, the pharmaceutical research groups across the world are sufficiently motivated to discover or design small molecule inhibitors to treat cancer through inhibition of the immune checkpoint proteins previously targeted with monoclonal antibodies. The presented study was designed with an aim to establish raloxifene, a selective estrogen receptor modulator (SERM) as a potential ligand of the immune checkpoint protein Programmed death ligand-1 (PD-L1). METHODS: In the presented study, the in-silico approach was used for identifying a lead molecule against PD-L1. The hits were screened using the similarity-search method, and drug-likeliness analysis, and the leads were identified through ligand-docking using Autodock. In-vitro cytotoxicity analysis was carried out using the standard sulphorhodamine B (SRB) assay and the wound healing analysis to show the inhibition of cellular migration was performed using the standard scratch assay. RESULTS: The in-silico study revealed that raloxifene showed a high drug likelihood and higher binding affinity with PD-L1 as compared to the positive control (BMS-1166; BMS is Bristol Myers Squibb). The binding of raloxifene was shown to occur in the same region as the FDA-approved monoclonal antibodies atezolizumab and durvalumab, indicating the potential of raloxifene for PD1/PD-L1 blockade. In the in-vitro studies, raloxifene showed a time-dependent reduction in IC50 values for the cell line HCT116 (colon cancer). The scratch assay also revealed that raloxifene significantly reduced the migratory potential of HCT-116 cells in-vitro. CONCLUSIONS: PD-L1 is a potential target of the SERM raloxifene in-silico. Overall, this study is one step further towards immune checkpoint blockade using small-molecule inhibitors.

Sporulation in mycobacteria.

Mycobacteria owe their success as pathogens to their ability to persist for long periods within host cells in asymptomatic, latent forms before they opportunistically switch to the virulent state. The molecular mechanisms underlying the transition into dormancy and emergence from it are not clear. Here we show that old cultures of Mycobacterium marinum contained spores that, upon exposure to fresh medium, germinated into vegetative cells and reappeared again in stationary phase via endospore formation. They showed many of the usual characteristics of well-known endospores. Homologues of well-known sporulation genes of Bacillus subtilis and Streptomyces coelicolor were detected in mycobacteria genomes, some of which were verified to be transcribed during appropriate life-cycle stages. We also provide data indicating that it is likely that old Mycobacterium bovis bacillus Calmette-Guérin cultures form spores. Together, our data show sporulation as a lifestyle adapted by mycobacteria under stress and tempt us to suggest this as a possible mechanism for dormancy and/or persistent infection. If so, this might lead to new prophylactic strategies.

Prospective evaluation of complications using the modified Clavien grading system, and of success rates of percutaneous nephrolithotomy using Guy's Stone Score: A single-center experience.

INTRODUCTION AND OBJECTIVES: To prospectively document the perioperative complications of percutaneous nephrolithotomy (PCNL) using the modified Clavien grading system. Evaluation of complications and clearance rates according to stone complexity using the validated Guy's Stone Score (GSS) was also done. MATERIALS AND METHODS: A total of 221 renal units underwent 278 PCNL procedures at a urology resident training center between September 2010 and September 2011 and data were recorded prospectively in our registry. Patients with co-morbidities like diabetes, renal failure, hypertension and cardiopulmonary diseases were excluded. Stone complexity was classified according to the GSS while peri-operative complications were recorded using the modified Clavien grading system. RESULTS: Two hundred and forty-five complications were encountered in 278 PCNL procedures involving 116 renal units (41.72%). Complications of Grades 1, 2, 3a, 3b, 4a, 4b and 5 were seen in 52 (18.7%), 122 (43.8%), 42 (15.1%), 18 (6.4%), 6 (2.1%), 4 (1.4%) and 1 (0.3%) renal units respectively. There were 68, 98, 50 and 5 renal units in GSS I, II, III and IV groups, respectively. All grades of complications were more common in GSS III and IV (P<0.05). For GSS I, II, III and IV 100%, 74%, 56% and 0% of renal units, respectively, were stone-free after one session and 0%, 24%, 44% and 60% respectively needed two sessions to be stone-free. CONCLUSION: Although the complication rates were higher most were of low grade and self-limiting. Complications were significantly more common with higher GSS and the GSS effectively predicted stone-free rates.