Study on PTFE superhydrophobic coating modified by IC@dMSNs and its enhanced antibacterial effect

INTRODUCTION

Vascular catheter-related infections and thrombosis are common and may lead to serious complications after catheterization. Reducing the incidence of such infections has become a significant challenge.

OBJECTIVES

This study aims to develop a super hydrophobic nanocomposite drug-loaded vascular catheter that can effectively resist bacterial infections and blood coagulation.

METHODS

In this study, a SiO2 nanocoated PTFE (Polytetrafluoroethylene) catheter (PTFE-SiO2) was prepared and further optimized to prepare a SiO2 nanocoated PTFE catheter loaded with imipenem/cilastatin sodium (PTFE-IC@dMSNs). The catheters were characterized for performance, cell compatibility, anticoagulant performance, in vitro and in vivo antibacterial effect and biological safety.

RESULTS

PTFE-IC@dMSNs catheter has efficient drug loading performance and drug release rate and has good cell compatibility and anticoagulant effect in vitro. Compared with the PTFE-SiO2 catheter, the inhibition ring of the PTFE-IC@dMSNs catheter against Escherichia coli increased from 3.98 mm2 to 4.56 mm2, and the antibacterial rate increased from about 50.8 % to 56.9 %, with a significant difference (p < 0.05). The antibacterial zone against Staphylococcus aureus increased from 8.63 mm2 to 11.74 mm2, and the antibacterial rate increased from approximately 83.5 % to 89.3 %, showing a significant difference (p < 0.05). PTFE-IC@dMSNs catheter also has good biocompatibility in vivo. Furthermore, the PTFE-IC@dMSNs catheter can reduce the adhesion of blood cells and have excellent anticoagulant properties, and even maintain these properties even with the addition of imipenem/cilastatin sodium.

CONCLUSION

Compared with PTFE, PTFE-SiO2 and PTFE-IC@dMSNs catheters have good characterization performance, cell compatibility, and anticoagulant properties. PTFE SiO2 and PTFE-IC@dMSNs catheters have good antibacterial performance and tissue safety against E. coli and S. aureus. Relatively, PTFE-SiO2 and PTFE-IC@dMSNs catheter has better antibacterial properties and histocompatibility and has potential application prospects in anti-bacterial catheter development and anticoagulation.

Molecular insights of Eucalyptol (1,8-Cineole) as an anti-arthritic agent: in vivo and in silico analysis of IL-17, IL-10, NF-κB, 5-LOX and COX-2

The monoterpene oxide, Eucalyptol (1,8-Cineole), a primary component of eucalyptus oil, has been evaluated pharmacologically for anti-inflammatory and analgesic activity. Current research aimed to evaluate Eucalyptol's anti-arthritic potential in a Complete Freund's adjuvant induced arthritis that resembles human rheumatoid arthritis. Polyarthritis developed after 0.1 mL CFA injection into the left hind footpad in rats. Oral administration of Eucalyptol at various doses (100, 200 and 400 mg/kg) significantly reduced paw edema, body weight loss, 5-LOX, PGE2 and Anti-CCP levels. Real-time PCR investigation showed significant downregulation of COX-2, TNF-α, NF-κB, IL-17, IL-6, IL-1β and upregulation of IL-4 and IL-10 in Eucalyptol treated groups. Hemoglobin and RBCs counts significantly increased post-treatment with Eucalyptol while ESR, CRP, WBCs and platelets count significantly decreased. Eucalyptol significantly increased Superoxide Dismutase, Catalase and Glutathione levels compared to CFA-induced arthritic control however, MDA significantly decreased post-treatment. Further, radiographic and histopathological examination of the ankle joints of rodents administered Eucalyptol revealed an improvement in the structure of the joints. Piroxicam was taken as standard. Furthermore, molecular docking findings supported the anti-arthritic efficacy of Eucalyptol exhibited high binding interaction against IL-17, TNF-α, IL-4, IL-10, iNOS NF-κB, 5-LOX, and COX-2. Eucalyptol has reduced the severity of CFA induced arthritis by promoting anti-inflammatory cytokines for example IL-4, IL-10 and by inhibiting pro-inflammatory cytokines such as 5-LOX, COX-2, IL-17, NF-κB, TNF-α, IL-6 and IL-1β. Therefore, Eucalyptol might be as a potential therapeutic agent because of its pronounced anti-oxidant and anti-arthritic activity.

Seasonal Variation and Association of Heavy Metals in the Vital Organs of Edible Fishes from the River Jhelum in Punjab, Pakistan

The toxic effects of heavy metals are drastic, including accumulation. Fish species are important bio-indicators of heavy metal pollution in aquatic bodies. The current study aimed to assess the seasonal variation of heavy metals in the vital organs of mostly consumed fishes in River Jhelum, Pakistan. Samples of fish, including Wallago attu (Malhi), Rita rita (Khagga), and Mystus seenghala (Singhari), were collected from four different sites, i.e., Khushab, Muhammad Wala (M. Wala), 8.R.D and Rasool barrage during summer and winter seasons. Heavy metals such as iron (Fe), lead (Pb), chromium (Cr), cobalt (Co) and Cadmium (Cd) were estimated through acid digestion and spectrometric analysis. Results showed a significantly higher (P < 0.05) amount of these metals in the liver, followed by the kidneys of fish species. There were seasonal variations in the absorption of these metals as well. Cr (11.71) and Fe (58.66) were detected in higher amounts in Khagga which showed the greatest affinity for certain metals in some cases. In contrast, Singhari showed the greatest affinity to other metals in other cases. Comparative analysis revealed that there was a highly significant (P < 0.05) difference for the accumulation of almost all metals in both seasons and summer had the highest concentration of Cd, Pb, Co, Cr and Fe as compared to winter in all four sampling stations in the case of kidney and liver of all the three fishes. Elevated levels of heavy metals were detected in the summer due to increased temperature. Heavy metals found in the River Jhelum may demonstrate that metals can significantly affect the fish species.

Consanguineous marriages increase the incidence of recurrent tuberculosis: Evidence from whole exome sequencing

BACKGROUND

In this study, we have identified multiple mutations in the IL-12R1 gene among Pakistani patients who have inherited them through consanguineous marriages. These patients have experienced severe Bacille-Calmette-Guérin (BCG) infection as well as recurrent tuberculosis. We will demonstrate the pivotal role of interleukin (IL)-12/interferon (IFN)-γ axis in the regulation of mycobacterial diseases.

METHODOLOGY

First, we checked the patients' medical records, and then afterward, we assessed interferon-gamma (IFN-γ) production through ELISA. Following that, DNA was extracted to investigate IL-12/IFN- abnormalities. Whole exome sequencing was conducted through Sanger sequencing. Secretory cytokine levels were compared from healthy control of the same age groups and they were found to be considerably less in the disease cohort. To evaluate the probable functional impact of these alterations, an in silico study was performed.

RESULTS

The study found that the patients' PBMCs produced considerably less IFN-γ than expected. Analysis using flow cytometry showed that activated T cells lacked surface expression of IL-12Rβ1. Exon 7 of the IL-12Rβ1 gene, which encodes a portion of the cytokine binding region (CBR), and exon 10, which encodes the fibronectin-type III (FNIII) domain, were found to have the mutations c.641 A > G; p.Q214R and c.1094 T > C; p.M365T, respectively. In silico analysis showed that these mutations likely to have a deleterious effect on protein function.

CONCLUSION

Our findings indicate the significant contribution of the IL-12/IFN-γ is in combating infections due to mycobacterium. Among Pakistani patients born to consanguineous marriages, the identified mutations in the IL-12Rβ-1 gene provide insights into the genetic basis of severe BCG infections and recurrent tuberculosis. The study highlights the potential utility of newborn screening in regions with mandatory BCG vaccination, enabling early detection and intervention for primary immunodeficiencies associated with mycobacterial infections. Moreover, the study suggests at the potential role of other related genes such as IL-23Rβ1, TYK2, or JAK2 in IFN-γ production, warranting further investigation.

Evaluation of the antibacterial activity and protein profiling of Nile tilapia (Oreochromis niloticus) epidermal mucus under different feeds and culture systems (biofloc technology and earthen pond)

The mucus layers of fish serve as the main interface between the organism and the environment. They play an important biological and ecological role. The current study focuses on Nile tilapia epidermal mucus reared under different commercial feeds (coded A and B) and environments (biofloc technology and earthen pond systems). Crude protein levels in feed A and B were 30% and 28%, respectively. Water parameters in all culturing systems were suitable for tilapia throughout the study period. The antimicrobial potency of tilapia (n = 5 from each) epidermal mucus was tested in vitro against human and fish pathogenic strains viz. Staphylococcus epidermidis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Francisella noatunensis, and Aeromonas hydrophila. To determine the antimicrobial activity, zones of inhibition (ZOI) were measured in millimetres and compared with two antibiotics (chloramphenicol and ciprofloxacin). SDS-PAGE analysis was performed on skin mucus samples of tilapia to determine protein quantity and size (molecular weight). Results of tilapia skin mucus (crude and aqueous) revealed a strong antibacterial effect against all the selected pathogenic strains. However, variation has been observed in the mucus potency and ZOI values between the biofloc and pond tilapia mucus. The crude mucus of tilapia fed on feed A and cultured in the pond exhibited strong antibacterial effects and high ZOI values compared to the mucus of biofloc tilapia, aqueous mucus extracts and positive control chloramphenicol (antibiotic). The SDS-PAGE results showed that the high molecular weight proteins were found in the collected epidermal mucus of BFT-B (240 kDa) and EP-B (230 kDa). Several peptides in fish skin mucus may play a crucial role in the protection of fish against disease-causing pathogens. Thus, it can be utilized in the human and veterinary sectors as an 'antimicrobial' for treating various bacterial infections.

Synthesis, characterization and anti-breast cancer potential of an incensole acetate nanoemulsion from Catharanthus roseus essential oil; in silico, in vitro, and in vivo study

The characteristics of phytocompounds and essential oils have undergone extensive research in the medical and pharmaceutical sectors due to their extensive usage. In spite of the fact that these molecules are widely used, terpenes, terpenoids, and their derivatives have not yet been well characterized. This study intends to evaluate the prospective activity of incensole acetate (IA), a compound identified and isolated from Catharanthus roseus essential oil by GC/MS analysis and column chromatography, and to analyze the anticancer effect of an IA biosynthesized nanoemulsion against breast cancer. The in silico activity of IA against breast cancer targets was observed by molecular docking, ADMET assessment and molecular dynamics simulations. The IA-mediated nanoformulation exhibited cytotoxicity against breast cancer cell lines at an effective concentration when analyzed by MTT and crystal violet assay. The increased interleukin serum indicators were significantly improved as a result of nanoemulsion treatment in a DMBA-induced rat model. In addition, the anticancer properties of IA biosynthesized nanoemulsion are supported due to their potential effects on biochemical parameters, oxidative stress markers, proinflammatory cytokines, and upon tumor growth profiling in cancer-induced rats.

Evaluation of Antimicrobial, Anticholinesterase Potential of Indole Derivatives and Unexpectedly Synthesized Novel Benzodiazine: Characterization, DFT and Hirshfeld Charge Analysis

The pharmacological effectiveness of indoles, benzoxazepines and benzodiazepines initiated our synthesis of indole fused benoxazepine/benzodiazepine heterocycles, along with enhanced biological usefulness of the fused rings. Activated indoles 5, 6 and 7 were synthesized using modified Bischler indole synthesis rearrangement. Indole 5 was substituted with the trichloroacetyl group at the C⁷ position, yielding 8, exclusively due to the increased nucleophilic character of C⁷. When trichloroacylated indole 8 was treated with basified ethanol or excess amminia, indole acid 9 and amide 10 were yielded, respectively. Indole amide 10 was expected to give indole fused benoxazepine/benzodiazepine 11a/11b on treatment with alpha halo ester followed by a coupling agent, but when the reaction was tried, an unexpectedly rearranged novel product, 1,3-bezodiazine 12, was obtained. The synthetic compounds were screened for anticholinesterase and antibacterial potential; results showed all products to be very important candidates for both activities, and their potential can be explored further. In addition, 1,3-bezodiazine 12 was explored by DFT studies, Hirshfeld surface charge analysis and structural insight to obrain a good picture of the structure and reactivity of the products for the design of derivatised drugs from the novel compound.

Evaluation and Association of Heavy Metals in Commonly Used Fish Feed with Metals Concentration in Some Tissues of O. niloticus Cultured in Biofloc Technology and Earthen Pond System

For successful aquaculture, the primary need is the quality of fish feed, which determines fish flesh quality. The current study was conducted to evaluate the number and concentration of heavy metals in commonly used fish feeds and fish gills, liver, and muscle of biofloc technology and earthen pond systems. Besides this, the correlation between heavy metals in fish feeds with detected metals in the gills, liver, and muscle of fish was also determined. Results revealed that heavy metals concentration, including Cu and Cd, in feed B was significantly greater than in feed A, but the Zn level in feed A was significantly higher than in feed B. Furthermore, the concentration of heavy metals in fish of both aquaculture systems was significantly higher in the liver than in the gills and muscle. The metal concentration in fish feeds and fish edible parts (muscle) was lower than the WHO standard level; however, the amount of Pb was higher in the fish muscle, which is harmful for human consumption. Though the correlation test revealed that all of the metals from the feeds were positively correlated to the metals detected in the fish, but most of the estimated correlation was insignificant. From the current study, it can be concluded that the fish feed producers need to measure feed quality adequately to avoid hazardous contamination by heavy metals in the feed. The ultimate consumer, fish and humans, may, otherwise, be predisposed to assimilate and accumulate these heavy metals.

Synthesis, Crystal Structure, DFT Calculations, Hirshfeld Surface Analysis and In Silico Drug-Target Profiling of (R)-2-(2-(1,3-Dioxoisoindolin-2-yl)propanamido)benzoic Acid Methyl Ester

The work here reflects synthesis, DFT studies, Hirshfeld charge analysis and crystal data exploration of pharmacologically important (R)-2-(2-(1,3-dioxoisoindolin-2-yl)propanamido)benzoic acid methyl ester (5) to understand its properties for further chemical transformations. The methyl anthranilate (2) was produced by the esterification of anthranilic acid in an acidic medium. The phthaloyl-protected alanine (4) was rendered by the fusion of alanine with phthalic anhydride at 150 °C, followed by coupling with (2) furnished isoindole (5). The characterization of products was performed using IR, UV-Vis, NMR and MS. Single-crystal XRD also verified the structure of (5) in which N-H⋯O bonding stabilizes the molecular configuration of (5), resulting in the formation of S(6) hydrogen-bonded loop. The molecules of isoindole (5) are connected in the form of dimers, and the π⋯π stacking interaction between aromatic rings further stabilizes the crystal packing. DFT studies suggest that HOMO is over the substituted aromatic ring, the LUMO is present mainly over the indole side, and nucleophilic and electrophilic corners point out the reactivity of the product (5). In vitro and in silico analysis of (5) shows its potential as an antibacterial agent targeting DNA gyrase and Dihydroorotase from E. coli and tyrosyl-tRNA synthetase and DNA gyrase from Staphylococcus aureus.

Correction: Synthesis of an amantadine-based novel Schiff base and its transition metal complexes as potential ALP, α-amylase, and α-glucosidase inhibitors

[This corrects the article DOI: 10.1039/D2RA07051K.].

Chemical Characterization, Antioxidant, Antimicrobial, Cytotoxicity and in Silico Studies of Hexane Extract and Essential Oils from Citrus limon Leaves

The present study investigates the chemical composition, antioxidant and antimicrobial bioactivities of essential oil and hexane extract from Citrus limon leaves. The isolation of essential oil was carried out using the Clevenger apparatus. The percentage yield of essential oil and hexane extract from Citrus limon leaves was 0.59 and 0.50 %, respectively. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging assay highlighted that Citrus limon leaves essential oil (CLEO) and hexane extract exhibited the significant antioxidant potential of 69.64 and 67.55 %, respectively, compared to the BHT standard. Similarly, a significant inhibition in linoleic acid peroxidation was recorded in both CLEO (81.93 %) and hexane extract (50.34 %). Characterization of chemical constituents in CLEO and extract was executed using GC/MS, where Limonene was detected as a major compound in CLEO (60.52 %) and hexane extract (73.62 %). The haemolytic activity ranged from 2.46 to 5.75 % revealing negligible cytotoxicity of CLEO and hexane extract. In silico studies agree with the in vitro antimicrobial studies, where vinimalol, taraxasterol, and moretenol present in CLEO showed strong interactions/inhibition against dihydroorotase and DNA gyrase from E. coli, and the tyrosyl-tRNA synthetase and DNA gyrase from S. aureus. Based on the current data, it may be concluded that both CLEO and hexane extract possessed significant bioactivities, such as antimicrobial and antioxidant activity, with minimal cytotoxicity.

Assessment and Bioaccumulation of Heavy Metals in Fish Feeds, Water, and Some Tissues of Cyprinus carpio Cultured in Different Environments (Biofloc Technology and Earthen Pond System)

Fish feed quality is the main determinant of fish flesh quality, so it is important for successful aquaculture. The current study determines the concentration of heavy metals in fish feeds (A and B), water, and their bioaccumulation in gills, liver, and muscle of C. carpio cultured in different environments (biofloc technology and earthen pond systems). In addition, the correlation between heavy metals in fish feeds with bioaccumulated metals in fish tissues was also determined. Results revealed that most heavy metal concentration was significantly greater (P < 0.05) in feed B than in feed A but in permissible range, while all the heavy metal concentration was notably higher in earthen ponds than in biofloc technology. Result from the bioaccumulation factor and concentration of the metals showed that heavy metals were highly accumulated in the fish liver followed by gills. The metal concentration in fish feeds and fish edible parts (muscle) was lower than the WHO standard level; however, the amount of Pb was higher in the fish muscle, liver, and gills, which is harmful for human consumption and also for fish health. Though the correlation test revealed that all of the metals from the feeds were positively correlated to the metals in fish tissues, but most of the estimated correlation was significant and linearly correlated. It can be concluded that producers must measure feed quality correctly to avoid heavy metal contamination because it may assimilate and accumulate in the food chain.

Assessment of Genetic Damage in Coal Miners of Punjab, Pakistan

Coal miners are continuously exposed to coal mine dust and airborne particulate that act as a potential risk to their health. The present study evaluates the DNA damage in coal miners using the Buccal Micronucleus Cytome (BMCyt) assay. The samples of the blood and buccal epithelial cells of 40 coal miners and 20 control subjects were taken from coal mines of Pail and Padhrar, Pakistan, to establish buccal anomaly frequencies of metal levels in the blood. Besides this, work history and duration hours were also analyzed. Results revealed that micronucleus frequencies positively correlated with the metal concentrations in the miner's blood. The change in the extent of nuclear damage per unit change in the year was 0.170 for micronuclei; however, with addition in each year of working experience, nuclear buds and broken egged nuclei increased by 0.316 and 0.194 units, where each year increases karyolysis by 0.349 units and karyorrhexis by 0.308 units, respectively. An increase in work hours and working years was positively correlated with cytogenetic damage. Nuclear damage in coal miners due to occupational exposure is obvious and increases with increasing work experience. Hence, the Buccal Micronucleus Cytome assay has proved to be an effective cytogenetic biomonitoring tool for assessing genetic and nuclear damage in coal miners.

A novel construct of an electrochemical acetylcholinesterase biosensor for the investigation of malathion sensitivity to three different insect species using a NiCr2O4/g-C3N4 composite integrated pencil graphite electrode

Herein, an electrochemical biosensor has been prepared to assess the sensitivity of an organophosphate insecticide, malathion, to acetylcholinesterase (AChE) enzyme of three insects including Apis mellifera (honeybee), Tribolium castaneum (red flour beetle), and Zootermopsis nevadensis (dampwood termite). A composite of nickel chromite (NiCr₂O₄) and graphitic carbon nitride (g-C₃N₄) was prepared and characterized for its morphological, chemical and electrical properties. The NiCr₂O₄/g-C₃N₄ composite integrated pencil graphite electrodes were used to covalently immobilize insect AChE enzymes and amperometric response of bioelectrodes was determined through cyclic voltammetry. The prepared bioelectrodes exhibited high enzyme immobilization efficiency and electro-catalytic performance. The integrated bioelectrodes could efficiently detect malathion induced inhibition of insects' AChEs. The linear ranges for malathion were found to be 0.1–1.6 μM, 1–40 nM and 2–100 nM, and LODs were 2 nM, 0.86 nM and 2.3 nM for A. mellifera, T. castaneum, and Z. nevadensis, respectively. Additionally, the biosensing platform developed using A. mellifera AChE was found highly sensitive and effective for malathion recoveries from spiked wheat flour samples with high recovery rates. Moreover, the proposed method was adequately reproducible and selective. The results revealed that A. mellifera AChE is less sensitive to inhibition by malathion as compared to T. castaneum, and Z. nevadensis AChE. The experimental results were validated through computational docking of malathion with insect AChEs and the results were in correspondence to experimental outcomes. The proposed method can be a plausible alternate to conventional analytical methods to assess the pesticide sensitivity and toxicity of various compounds against insect enzymes.

An innovative electrochemical assay has been established to determine pesticide sensitivity against acetylcholinesterase and possible toxicity against insects. The analytical efficiency of three common insect AChEs was determined through this method.

Assessment of pesticide induced inhibition of Apis mellifera (honeybee) acetylcholinesterase by means of N-doped carbon dots/BSA nanocomposite modified electrochemical biosensor

This work describes the development and optimization of an electrochemical method to evaluate pesticide induced inhibition of honey bee (Apis mellifera) acetylcholinesterase (AChE) by means of acetylcholinesterase biosensor. The inhibition assay was based on the detection of changes in electrochemical activity of the enzyme caused by pesticide. As transducer, nitrogen doped carbon dots BSA (N-CD/BSA) nanocomposite electrodeposited on pencil graphite electrode was used to covalently immobilize AChE. The as-synthesized nanocomposite and fabricated electrodes were characterized for the structural, functional and electrochemical properties. Nanocomposite promoted the electron transfer reaction to catalyze the electro-oxidation of thiocholine and a large current response was obtained by cyclic voltammetry at 0.77 V, indicating successful immobilization of AChE. The sensitivity of Diazinon, an OP insecticide, for honeybee AChE was tested under optimal conditions and a linear response ranging 10-250 nM was obtained with a detection limit of 8.9 nM, and sensitivity 9 uA/nM/cm². The method showed a good operational reproducibility and selectivity of biosensor. Further, the molecular docking provided additional support to the experimental data suggesting irreversible nature and contact toxicity of the pesticide for honey bee AChE. The developed biosensor has proved useful for the diazinon detection in wheat samples with 99% recovery rate.

Molecular engineering of indenoindene-3-ethylrodanine acceptors with A2-A1-D-A1-A2 architecture for promising fullerene-free organic solar cells

Considering the increased demand and potential of photovoltaic devices in clean, renewable electrical and hi-tech applications, non-fullerene acceptor (NFA) chromophores have gained significant attention. Herein, six novel NFA molecules IBRD1-IBRD6 have been designed by structural modification of the terminal moieties from experimentally synthesized A2-A1-D-A1-A2 architecture IBR for better integration in organic solar cells (OSCs). To exploit the electronic, photophysical and photovoltaic behavior, density functional theory/time dependent-density functional theory (DFT/TD-DFT) computations were performed at M06/6-311G(d,p) functional. The geometry, electrical and optical properties of the designed acceptor molecules were compared with reported IBR architecture. Interestingly, a reduction in bandgap (2.528-2.126 eV), with a broader absorption spectrum, was studied in IBR derivatives (2.734 eV). Additionally, frontier molecular orbital findings revealed an excellent transfer of charge from donor to terminal acceptors and the central indenoindene-core was considered responsible for the charge transfer. Among all the chromophores, IBRD3 manifested the lowest energy gap (2.126 eV) with higher λmax at 734 and 745 nm in gaseous phase and solvent (chloroform), respectively due to the strong electron-withdrawing effect of five end-capped cyano groups present on the terminal acceptor. The transition density matrix map revealed an excellent charge transfer from donor to terminal acceptors. Further, to investigate the charge transfer and open-circuit voltage (Voc), PBDBT donor polymer was blended with acceptor chromophores, and a significant Voc (0.696-1.854 V) was observed. Intriguingly, all compounds exhibited lower reorganization and binding energy with a higher exciton dissociation in an excited state. This investigation indicates that these designed chromophores can serve as excellent electron acceptor molecules in organic solar cells (OSCs) that make them attractive candidates for the development of scalable and inexpensive optoelectronic devices.

Efficacy of Biodegradable Polydioxanone and Polylactic Acid Braided Biodegradable Biliary Stents for the Management of Benign Biliary Strictures

BACKGROUND

Benign biliary strictures (BBS) are widely treated by endoscopic procedures involving temporary stent placement. Occasionally, stents are required to be removed, making the treatment process very painful as well as expensive. Until now, no effective biodegradable biliary stents are available for clinical applications. This study aims to investigate the safety and efficacy of biodegradable polydioxanone (PDO) and polylactic acid (PLA) braided biodegradable biliary stents (BDBS) both in vitro and in vivo.

METHODS

Three different diameter monofilaments of PDO (0.30, 0.35, and 0.40 mm) and PLA (0.10, 0.15, and 0.20 mm) were braided to biliary stents and their mechanical properties were studied. The stents were placed in an ex vivo bile duct model perfused with porcine bile, taken out, and observed every week until these were completely degraded. After the bile duct stenosis model was established successfully in piglet, stents with appropriate mechanical properties were further examined under endoscopy; haematology, patency time of stents, and pathological changes were observed for eight months.

RESULTS

A total of 10 pigs were included (two groups; 5 PDO, 5 PLA) in the study. The patency time of the PLA group was significantly longer than that of the PDO stent group (25.7 ± 5.6w vs 11.3 ± 3.4w, respectively) in pigs.

CONCLUSION

Our results prospect biodegradable PLA and PDO braided biliary stents could be a better choice to treat benign biliary strictures while degrading at different rates.

Gastric Cancer Screening Methods: A Comparative Study of Two Scoring Methods

Objective

To evaluate the Li’s and Japanese scoring methods scoring for screening early gastric cancer in a healthy population.

Methods

During January 2016–December 2018, profiles of the healthy people participated in a physical examination in the first people’s Hospital of Shanghai were collected. A total of 342 volunteers, including 137 males and 205 females ageing 40–74, were enrolled. After recording the basic information, all volunteers were scored using the Japan scoring method and the new gastric cancer screening score (ie, Li’s score). The subjects’ work characteristics (ROC curve) were drawn according to the patient’s endoscopic pathological examination to indicate early gastric cancer, to determine the best cut-off point for the diagnosis of early gastric cancer by Japanese scoring and Li’s scoring, respectively. The sensitivity and specificity of both scoring methods were calculated as well.

Results

The area under the ROC curve of Japanese and Li’s score, in the diagnosis of early gastric cancer, was 0.763 and 0.837, respectively. Japanese and Li’s score ≥14 were considered as the best cut-off point. The sensitivity and specificity of Li’s scoring were 63.60% and 91.10%, respectively. The sensitivity and specificity of the Japanese score were 54.50% and 87.50%, respectively. The area under the ROC curve in Li’s scoring is more significant than that in Japanese scoring, and there was a substantial difference in the two methods (P<0.05).

Conclusion

Both Li’s scoring and Japanese scoring have shown good screening value for early gastric cancer in a healthy population, but Li’s scoring is more sensitive/specific than Japanese scoring.

An insect acetylcholinesterase biosensor utilizing WO3/g-C3N4 nanocomposite modified pencil graphite electrode for phosmet detection in stored grains

This study was undertaken to assess the potential of Tribolium castaneum (Red flour beetle) acetylcholinesterase (Tc-AChE) based electrochemical biosensor integrating WO₃/g-C₃N₄ nanocomposite modified Pencil graphite electrode to detect an organophosphate insecticide, Phosmet. The WO₃/g-C₃N₄ nanocomposite provides a non-toxic, biocompatible surface for binding the enzyme on the electrode surface, attributed to its large surface area, high conductivity, and low ohmic resistance. The proposed biosensor shows a very good analytical performance with LOD 3.6 nM for Phosmet and effectively determined Phosmet in wheat with a 99% recovery rate. Furthermore, molecular docking deciphers the binding interactions of Phosmet with Tc-AChE using a modified AutoDock LGA algorithm and an AMBER03 force field in YASARA. The kinetic parameters strongly suggest the high potency of inhibitor with the enzyme. This study presents an adaptable, rapid, and straightforward approach that opens ways towards real progress in developing commercial biosensors for pesticide detection.

Challenges for biosimilars: focus on rheumatoid arthritis

Healthcare systems worldwide are struggling to find ways to fund the cost of innovative treatments such as gene therapies, regenerative medicine, and monoclonal antibodies (mAbs). As the world's best known mAbs are close to facing patent expirations, the biosimilars market is poised to grow with the hope of bringing prices down for cancer treatment and autoimmune disorders, however, this has yet to be realized. The development costs of biosimilars are significantly higher than their generic equivalents due to therapeutic equivalence trials and higher manufacturing costs. It is imperative that academics and relevant companies understand the costs and stages associated with biologics processing. This article brings these costs to the forefront with a focus on biosimilars being developed for Rheumatoid Arthritis (RA). mAbs have remarkably changed the treatment landscape, establishing their superior efficacy over traditional small chemicals. Five blockbuster TNFα mAbs, considered as first line biologics against RA, are either at the end of their patent life or have already expired and manufacturers are seeking to capture a significant portion of that market. Although in principle, market-share should be available, withstanding that the challenges regarding the compliance and regulations are being resolved, particularly with regards to variation in the glycosylation patterns and challenges associated with manufacturing. Glycan variants can significantly affect the quality attributes requiring characterization throughout production. Successful penetration of biologics can drive down prices and this will be a welcome change for patients and the healthcare providers. Herein we review the biologic TNFα inhibitors, which are on the market, in development, and the challenges being faced by biosimilar manufacturers.

Exploration of Noncovalent Interactions, Chemical Reactivity, and Nonlinear Optical Properties of Piperidone Derivatives: A Concise Theoretical Approach

The organic compounds with a π-bond system lead to electric charge delocalization which enables them to reveal fascinating nonlinear optical properties. Mono-carbonyl curcuminoids also have an appealing skeleton from the conjugation view point. Interesting chemical structures of the 3,5-bis(arylidene)-N-benzenesulfonyl-4-piperidone derivatives motivated us to perform density functional theory (DFT)-based studies. Therefore, computations using the B3LYP/6-311G(d,p) functional of DFT were executed to explore geometric parameters, highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) energies, and natural bond orbital (NBO) analyses. Moreover, three different functionals such as HF, B3LYP, and M06 with the 6-311G(d,p) basis set were used to investigate the average polarizability ⟨α⟩ and first hyperpolarizability (β_tot)-based properties of all compounds. A good concurrence among calculated and experimental parameters was obtained through root mean square error calculations. The molecular stability of piperidone derivatives was examined using the Hirshfeld surface and NBO analyses. Natural population analysis was also performed to obtain insights about atomic charges. Calculated HOMO-LUMO energies showed that charge transfer interactions take place within the molecules. Moreover, global reactivity parameters including electronegativity, chemical hardness, softness, ionization potential, and electrophilicity were calculated using the HOMO and LUMO energies. The average polarizability ⟨α⟩ and first hyperpolarizability (β_tot) values of all compounds were observed to be larger in magnitude at the aforesaid functional than the standard compound.