Bimetallic Au-Ag Nanoparticles: Advanced Nanotechnology for Tackling Antimicrobial Resistance.

To date, there are no antimicrobial agents available in the market that have absolute control over the growing threat of bacterial strains. The increase in the production capacity of antibiotics and the growing antibacterial resistance of bacteria have majorly affected a variety of businesses and public health. Bimetallic nanoparticles (NPs) with two separate metals have been found to have stronger antibacterial potential than their monometallic versions. This enhanced antibacterial efficiency of bimetallic nanoparticles is due to the synergistic effect of their participating monometallic counterparts. To distinguish between bacteria and mammals, the existence of diverse metal transport systems and metalloproteins is necessary for the use of bimetallic Au-Ag NPs, just like any other metal NPs. Due to their very low toxicity toward human cells, these bimetallic NPs, particularly gold-silver NPs, might prove to be an effective weapon in the arsenal to beat emerging drug-resistant bacteria. The cellular mechanism of bimetallic nanoparticles for antibacterial activity consists of cell membrane degradation, disturbance in homeostasis, oxidative stress, and the production of reactive oxygen species. The synthesis of bimetallic nanoparticles can be performed by a bottom-up and top-down strategy. The bottom-up technique generally includes sol-gel, chemical vapor deposition, green synthesis, and co-precipitation methods, whereas the top-down technique includes the laser ablation method. This review highlights the key prospects of the cellular mechanism, synthesis process, and antibacterial capabilities against a wide range of bacteria. Additionally, we also discussed the role of Au-Ag NPs in the treatment of multidrug-resistant bacterial infection and wound healing.

Comparative analysis of the seasonal influence on polyphenolic content, antioxidant capacity, identification of bioactive constituents and hepatoprotective biomarkers by in silico docking analysis in Premna integrifolia L.

The present study reports the effect of different seasons on polyphenol content and antioxidant potential of ethanolic, methanolic, ethyl acetate, and aqueous extracts of leaves, stems, and roots of Premna integrifolia. Ethyl acetate extract of leaves (EAEPI) collected in the rainy season showed potent antioxidant activity with highest total phenol (74.33 ± 2.26 µg/mg, gallic acid equivalent), and flavonoid (98.83 ± 0.26 µg/mg, rutin equivalent) content. Therefore, EAEPI extract was subjected to characterization by UHPLC-Q-TOF-MS/MS and GC-MS analysis for the identification of active constituents. UHPLC-Q-TOF-MS/MS analysis in + ve ion mode revealed the presence of eight polyphenolic compounds namely quercetin-3-D-xyloside, kaempferol-3,7-O-bis-alpha-L-rhamnoside, isorhamnetin-3-Oglucoside, luteolin-3',7-di-O-glucoside, eriodictyol-7-O-glucoside, syringetin-3-O-galactoside, petunidin-3-O-beta-glucopyranoside and vitexin-2″-O-rhamnoside. GC-MS analysis confirmed the presence of 26 compounds with six major compounds viz; citronellol, phytol acetate, campesterol, squalene, stigmasterol, and hexadecanoic acid. These compounds are reported for the first time from P. integrifolia except phytol and stigmasterol. Our previous study validates the hepatoprotective potential of P. integrifolia but there was no idea about the bioactive compound responsible for the activity. So, in present work, the major compounds identified in spectrometry analysis were subjected to in silico docking against an important liver enzyme alanine amino transaminase to confirm its hepatoprotective properties. Docking analysis validates the presence of two hepatoprotective lead compounds stigmasterol, and campesterol, which satisfy the drug-likeness criteria with good absorption, distribution, metabolism, and toxicity properties. Thus, present work gives a clear insight about the influence of season on the total polyphenolic constituent in different plant parts of P. integrifolia, their antioxidant potential and preclinical evaluation of hepatoprotective lead compounds.

Cesarean section under epidural anesthesia in a documented case of ruptured aneurysm of the sinus of valsalva.

Ruptured aneurysm of sinus of Valsalva (RSOV) occurring in pregnancy is a rare cardiac anomaly and it may be either congenital or acquired. Congenital sinus of Valsalva aneurysms are commonly associated with other structural defects such as ventricular septal defect (50-55%), aortic regurgitation (AR) (25-35%), bicuspid aortic valve (10-15%) and Marfan's syndrome (10%). RSOV in pregnancy accentuates the hemodynamic stress on maternal cardiovascular system and pose a significant challenge from obstetric anesthesia point of view. We report a case of 35-year-old documented patient of RSOV with mild AR presenting completely asymptomatic at 37 weeks 4 days of gestation. A successful elective lower segment cesarean section was conducted under epidural anesthesia.

Nanofibers of N,N,N-trimethyl chitosan capped bimetallic nanoparticles: Preparation, characterization, wound dressing and in vivo treatment of MDR microbial infection and tracking by optical and photoacoustic imaging.

Recent advancements in wound care have led to the development of interactive wound dressings utilizing nanotechnology, aimed at enhancing healing and combating bacterial infections while adhering to established protocols. Our novel wound dressings consist of N,N,N-trimethyl chitosan capped gold­silver nanoparticles (Au-Ag-TMC-NPs), with a mean size of 108.3 ± 8.4 nm and a zeta potential of +54.4 ± 1.8 mV. These optimized nanoparticles exhibit potent antibacterial and antifungal properties, with minimum inhibitory concentrations ranging from 0.390 µg ml-1 to 3.125 µg ml-1 and also exhibited promising zones of inhibition against multi-drug resistant strains of S. aureus, E. coli, P. aeruginosa, and C. albicans. Microbial transmission electron microscopy reveals substantial damage to cell walls and DNA condensation post-treatment. Furthermore, the nanoparticles demonstrate remarkable inhibition of microbial efflux pumps and are non-hemolytic in human blood. Incorporated into polyvinyl alcohol/chitosan nanofibers, they form Au-Ag-TMC-NPs-NFs with diameters of 100-350 nm, facilitating efficient antimicrobial wound dressing. In vivo studies on MDR microbial-infected wounds in mice showed 99.34 % wound healing rate within 12 days, corroborated by analyses of wound marker protein expression levels and advanced imaging techniques such as ultrasound/photoacoustic imaging, providing real-time visualization and blood flow assessment for a comprehensive understanding of the dynamic wound healing processes.

Phytochemical profiling and cytotoxic evaluation of Premna serratifolia L. against human liver cancer cell line.

Premna serratifolia L. (Lamiaceae) is a medicinal plant, widely distributed in the tropical and subtropical regions and commonly used in traditional medicine. The current study was focused to evaluate the cytotoxic potential of aqueous extract of root of P. serratifolia (AEPS) against human hepatoblastoma cancer cell line (Hep G2).The yield of the dried extract was 5.8% and used for further studies.Cytotoxic potential of AEPS was analyzed by MTT assay, which exhibits IC50 value 1000 µg/mL after 48 h incubation. Hoechst and AO/EtBr staining, ROS measurement, mitochondrial membrane potential, clonogenic and wound healing assays also confirmed the cytotoxic efficacy of AEPS in dose and time-dependent manner. UPLC-Q-TOF-MS/MS analysis of AEPS confirmed the presence of 12polyphenolic compounds, namely 4-hydroxy-3-methoxycinnamic acid, linarin, peonidin-3,5-O-di-beta-glucopyranoside, diosmin, trans-cinnamic acid, daidzein, saponarin, homoorietin, acacetin, sarsasapogenin, phytol and sissotrin. The cytotoxic potential of AEPS might due to presence of biologically active polyphenolic compounds.

Toxicity profiling and antioxidant activity of ethyl acetate extract of leaves of Premna integrifolia L. for its application as protective agent against xenobiotics.

Premna integrifoliaL. (Lamiaceae) is widely used in herbal formulation "Dashmoolarishta" which is useful in postnatal care. Ethyl acetate extract obtained from the leaves was evaluated for phenolic content and its antioxidant activity. Acute and subacute toxicity of the extract was studied in mice of both sexes to get an idea about LD50 value and assessed its safety profile before its application as a protective agent against different toxicities induced by xenobiotics. Phenol enriched extract (phenol content is 63.10 ± 1.26 mg/g of gallic acid equivalent and flavonoid content 75.33 ± 0.23 mg/g of rutin equivalent) showed good antioxidant activity. In acute toxicity studies it was observed that single different doses (300-5000 mg/kg b.wt.) of extract did not show any mortality of mice. Thus the LD50 of the extract was determined, and it was higher than 5000 mg/kg. There was no major change in behavioral and general appearance of mice. External morphology of liver, kidneys, lungs, spleen and heart did not show any effect of treatment. In subacute toxicity no statistically significant change in body weight, relative organ weight, food intake and water uptake, hematological, biochemical parameters were reported after comparison with control. Extract did not show significant effect in the level of antioxidant enzymes in the liver of mice of treated groups. No histopathological changes were observed in liver and kidney tissues. Thus, extract did not show any sign of toxic effects, when administered orally to male and female mice at dose level up to 1000 mg/kg. So, it can be utilized as protective agent against toxicity produced by different xenobiotics.

Hepatoprotective efficacy of Premna integrifolia L. leaves against aflatoxin B1-induced toxicity in mice.

The present study evaluated the hepatoprotective role of ethanol extract of P. integrifolia leaves (EEPL) on aflatoxin B1 (AFB1)-induced toxicity in mice. Mice were administered with AFB1 (0.1 mg/kg b. wt., orally) for 90 days, EEPL (400 and 600 mg/kg b. wt., orally) and silymarin (100 mg/kg b. wt., orally) in combination with AFB1. The study shows the protective effect of EEPL by the restoration of altered hematological indices and liver marker enzymes. Restoration of lipid peroxidation and glutathione content, along with activities of antioxidant enzymes, suggest amelioration of oxidative stress in AFB1-intoxicated mice. In addition, EEPL attenuated apoptosis and histopathological alterations in liver tissue. In conclusion, the current study suggests that EEPL protect mice liver against AFB1 toxicity by inhibiting oxidative stress and apoptosis. The protective activity of EEPL may be due to the enrichment of flavonoids (neohesperidin, apigenin-7-O-glucoside, catechin hydrate, cyanidin chloride, quercetin-3-galactoside, diosmin, genistein, malvin chloride, 4-hydroxy-3-methoxycinnamic acid, kaempferol-3-O-alpha-L-arabinoside, myricitrin, poncirin, vitexin and tiliroside) in the extract as identified by UPLC-QTOF-MS/MS.

Premna integrifolia ameliorates cyclophosphamide-induced hepatotoxicity by modulation of oxidative stress and apoptosis.

The present study was designed to evaluate the ameliorative effect of ethyl acetate extract of Premna integrifolia L. (EAEPI) leaves in cyclophosphamide (CP)-induced hepatic injury in mice. Mice were intoxicated with CP (200 mg/kg b. wt., i.p.) for 5 weeks or EAEPI (400 and 600 mg/kg b. wt., orally) in combination with CP. The results demonstrated that EAEPI exerts protective effect against CP induced hepatotoxicity, as evident from restoration of altered haematological parameters and alleviations of liver marker enzymes in serum. EAEPI also attenuated oxidative stress and antioxidant markers as evident from reversal of lipid peroxidation, glutathione levels as well as activities of catalase and superoxide dismutase enzymes. Moreover, EAEPI attenuated apoptosis and histopathological liver tissue damage in CP-intoxicated mice. In conclusion, EAEPI could protect mice liver against cyclophosphamide toxicity by inhibiting oxidative stress and apoptosis.The protective activity of EAEPI may be due to presence of polyphenolic compounds as identified by UHPLC-Q-TOF-MS/MS.

Erratum: Anatomical model broncho-trainer: A new training device: Corrigendum.

[This corrects the article on p. 481 in vol. 58, PMID: 25197126.].

A Comparative study on Adenosine and Magnesium Sulphate with Bupivacaine in Infraclavicular infusion for Postoperative Analgesia

Background: Brachial plexus piece has reformed the field of regional anaesthesia for upper limb surgeries. Infraclavicular subcoracoid approach gives complete block without significant difficulties. Aim: To compare the additives adenosine and magnesium sulphate with bupivacaine in infraclavicular infusion for upper limb surgeries and postoperative analgesia. Materials & Methods: This Prospective study was done at the Department of Anaesthesiology, Govt. Medical College, Azamgarh. Around 24 patients scheduled for elective unilateral upper limb surgeries involving distal arm/ elbow/ forearm/hand divided into two groups A (n-12) and B (n-12) randomly. Group A - adenosine 6mgs with 28 ml 0.5% bupivacaine bolus followed by infusion of 0.25% bupivacaine 28ml with 6mgs of adenosine (2ml) at a rate of 5ml/hr. Group B - magnesium sulphate 75 mgs (in 2ml) with 28ml of 0.5% bupivacaine bolus followed by infusion of 0.25% bupivacaine 28ml with 75mgs of magnesium sulphate (in 2ml) at a rate of 5ml/hr in USG guided placement of infraclavicular catheter. Results: Our Study revealed  that  Group  A  had a  faster Onset time of sensory and motor block and faster recovery when compared to group B. Group A needed more rescue analgesia than group B. Conclusion: The addition of magnesium sulphate as an additive to bupivacaine in brachial plexus block may be a better choice when prolonged postoperative analgesia is required.