A sensitive refining of in vitro and in vivo toxicological behavior of green synthesized ZnO nanoparticles from the shells of Jatropha curcas for multifunctional biomaterials development

ZnO nanoparticles (NPs) possess a wide range of biological functions in pharmaceutical and cosmetic applications due to their excellent antimicrobial, optical and UV protective properties. This study first reports the toxicological assessment of ZnO NPs green synthesized from Jatropha curcas shells for multifunctional biomedical applications. The hot water extract of J.curcas shells is utilized as a chelating agent for the reduction of zinc acetate and then, the prepared ZnO NPs are broadly characterized using X-ray spectroscopic and electron microscopic observations. The prepared ZnO NPs acquire high purity (100%) wurtzite crystal with hexagonal structure with the average particle size of 53 nm. In vitro and in vivo toxicity evaluation against human tumor cell lines and zebrafish embryos have ascertained the purpose of ZnO NPs in clinical research. Toxic effects of ZnO NPs were observed by a dose-dependent reduction of bacterial growth at ≥1   μg ml^-1, by teratogenicity and genotoxicity in zebrafish embryos (from 3 to 90 μg ml^-1) and by a significant nanoparticle uptake (0.5 ng μl^-1) by a fish serum. In contrast, ZnO NPs fail to reduce the proliferation of human bladder tumor cells (UC6) and cell viability of A549 cells in vitro up to 500 μg ml^-1. All these observations limit the unobstructed application of ZnO NPs at higher concentrations. Thus, abundantly used metal oxide nanoparticles like ZnO NPs examined in our present study in different animal models under in vitro and in vivo conditions will be the significant screening strategy to determine the nanotoxicity.

Bullous pemphigoid associated with dipeptidyl peptidase-4 inhibitor - A case report

Dipeptidyl peptidase-4 inhibitors (DPP-4i) are one of the mainstay drugs in the management of type 2 diabetes mellitus. It has been well-documented that these class of drugs cause allergic reactions. Bullous pemphigoid (BP) is a blistering skin condition commonly associated with many drugs. Here, we report a case of probable DPP-4i-induced BP in an elderly man, which resolved on discontinuation of the drug. Although this adverse drug reaction has been documented in Western world and Japanese ethnicity, this seems to be the first case report of such occurrence in Indian ethnicity.

Radiological-pathological correlation of the British Thyroid Association ultrasound classification of thyroid nodules: a real-world validation study

AIM

To evaluate the real-world performance of the British Thyroid Association (BTA) U classification, specifically focusing on radiology-pathology correlation and to glean learning points.

METHODS AND MATERIALS

Adults undergoing a neck ultrasound for thyroid nodules were reviewed over a period of 1-year. Data including demographics, nodule characteristics, BTA grading, and cytology/histopathology were retrieved with a minimum 24-month follow-up.

RESULTS

Of 1,225 graded nodules in 964 patients, cytology and/or histology were available for 300 (24%). 57 cancers were detected. Of 24 (2%) U5 nodules, 14 were malignant, of 51 (4%) U4, 22 were malignant, of 256 (21%) U3, 20 were malignant, and from 894 (73%) U2 nodules, one cancer was discovered. BTA U grading with fine-needle aspiration (FNA)/core biopsy achieved 96.5% sensitivity, 93.7% specificity, and 93.9% accuracy compared to excision. There was no association between nodule size and rate of malignancy.

CONCLUSION

This is the first study to validate the use of the BTA U-grading system in UK clinical practice. The BTA U-grading system is a robust and reliable method of evaluating the risk of malignancy in thyroid nodules with a high negative predictive value. Key learning points gleaned from the study were accurate assessment of nodule echogenicity, careful evaluation of solid-cystic nodules, optimising ultrasound technique, and the low-risk nature of U3 nodules.

Crystal structures of disordered Z-type helices

The X-ray crystal structures of a decamer sequence d(CGCGTACGCG)₂ and a tetradecamer sequence d(CGCGCGTACGCGCG)₂ are presented here. Both sequences are alternating pyrimidine-purine repeat sequences and they form disordered, pseudo-continuous left handed Z-type helices. They demonstrate interesting variants of the 'bundles of columns of helices' mode of packing.

A facile method for high level dual expression of recombinant and congener protein in a single expression system

Protein engineering is an emerging field for developing novel therapeutic proteins and commercial enzymes, along with a major impact on the global market. In recent decades, advanced methods employing protein modification through expansion of the genetic code have led to the development of proteins with new biochemical and physical properties. These techniques have produced engineered proteins with improved attribute comprising substrate relaxation, protein drug conjugation and high stability under extreme conditions of high temperatures, pH and organic solvents. Furthermore, residue specific incorporation is the simplest method for the global incorporation of non-canonical amino acid (NCAA) for protein modification; however it has the major drawbacks of high production cost and manpower requirement. In the present study, we developed a method for the incorporation of single NCAA in two different proteins by using Escherichia coli (E. coli) expression system. For that, the dual protein expressing Escherichia coli JW2581 strain was constructed by transforming pQE80L and pD881-PpiBT vectors with different promoters, selectable markers and AnnexinV, GFPHS gene. To modify the protein, the 3,4 dihydroxy phenyl alanine (DOPA) was globally incorporated into the GFPHS and Annexin V protein using dual protein expression system. The incorporation efficiency during the dual protein expression was achieved through optimized concentrations of amino acids, carbohydrate and inducers in minimal medium. This method for the incorporation of single NCAA into two different proteins using a single expression host system saves the production cost, manpower and time substantially.

Lung cancer stage-shift following a symptom awareness campaign

BACKGROUND

Lung cancer outcomes in the UK are worse than in many other developed nations. Symptom awareness campaigns aim to diagnose patients at an earlier stage to improve cancer outcomes.

METHODS

An early diagnosis campaign for lung cancer commenced in Leeds, UK in 2011 comprising public and primary-care facing components. Rates of community referral for chest X-ray and lung cancer stage (TNM seventh edition) at presentation were collected from 2008 to 2015. Linear trends were assessed by χ² test for trend in proportions. Headline figures are presented for the 3 years pre-campaign (2008-2010) and the three most recent years for which data are available during the campaign (2013-2015).

FINDINGS

Community-ordered chest X-ray rates per year increased from 18 909 in 2008-2010 to 34 194 in 2013-2015 (80.8% increase). A significant stage shift towards earlier stage lung cancer was seen (χ²(1)=32.2, p<0.0001). There was an 8.8 percentage point increase in the proportion of patients diagnosed with stage I/II lung cancer (26.5% pre-campaign vs 35.3% during campaign) and a 9.3% reduction in the absolute number of patients diagnosed with stage III/IV disease (1254 pre-campaign vs 1137 during campaign).

INTERPRETATION

This is the largest described lung cancer stage-shift in association with a symptom awareness campaign. A causal link between the campaign and stage-shift cannot be proven but appears plausible. Limitations of the analysis include a lack of contemporary control population.

Comparison of X-ray crystal structures of a tetradecamer sequence d(CCCGGGTACCCGGG)2 at 1.7 Å resolution

We present here a comparison of three different X-ray crystal structures of DNA tetradecamer sequence d(CCCGGGTACCCGGG)₂ all at about 1.7 Å resolution. The sequence was designed as an attempt to form a DNA four-way junction with A-type helical arms. However, in the presence of zinc, magnesium, and in the absence of any metal ion, it does not take up the junction structure, but forms an A-type double helix. This allowed us to study possible conformational changes in the double helix due to the presence of metal ions. Upon addition of the zinc ion, there is a change in the space group from P4₁2₁2 to P4₁. The overall conformation of the duplex remains the same. There are small changes in the interaction of the metal ions with the DNA. In the zinc-bound structure, there are two zinc ions that show direct interaction with the N7 atoms of terminal G₁₃ bases at either end of the molecule. There are small changes in the interhelical contacts. The consequence of these differences is to break some of the symmetry and change the space group.

Alcohol-related cue-reactivity predicts abstinence duration in individuals with severe alcohol-use disorders

Introduction

Alcohol use disorder (AUD) is an important global public health problem with complex aetiology and relapsing remitting course. Clinical measures of alcohol dependence severity and alcohol-craving, are largely unreliable in identifying individuals at high-risk for relapse. Functional human neuroimaging methods that employ symptom provocation paradigms have shown promise in identifying critical brain regions with cue-elicited alcohol-craving response.

Objective

The present study aimed at examining the utility of fMRI cue-reactivity (CR) in predicting relapse risk.

Methods

The study was conducted on inpatients of a tertiary care neuropsychiatric hospital. Thirty-two treatment-seeking right-handed men were recruited for the study after informed consent. Following detoxification and 3-day drug-washout period, they underwent a task-based fMRI while viewing images of alcohol-related and control cues presented to them using a previously validated fMRI paradigm. All patients received anti-craving medications (baclofen: 60–80 mg/d, n = 16; naltrexone: 50–100 mg/d, n = 16) and were prospectively followed-up till their first alcohol lapse.

Results

Random-effect analysis using one-sample test revealed significant CR to alcohol-related cues (relative to implicit baseline) with activation in salience-reward related regions [insula, cingulate, dorsal striatum (DS)], visual-attention regions [occipito-temporal] and deactivation of default-mode regions [posterior cingulate (PCC)] (all significant at PFWE < 0.05, whole-brain corrected). Cox-proportional hazard regressions revealed that greater CR in Insula (Chi2 = 10.33; P = 0.001; HR = 3.1; 95% CI = 1.5–6.3) and DS (Chi2 = 10.87; P = 0.001; HR = 2.8; 95% CI = 1.5–5.2) predicts faster subsequent time to first drink after accounting for the role of clinical measures.

Conclusion

These findings indicate that CR can serve as potential marker to identify individuals at high-risk for relapse. Further examination of intervention-related CR change may aid in personalizing treatment of AUD.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Coumarin polycaprolactone polymeric nanoparticles: light and tumor microenvironment activated cocktail drug delivery

Highly sensitive hypoxia (H₂O₂)-activated photoresponsive polymeric nanoparticles for cocktail delivery of anticancer drugs doxorubicin (Dox) and chlorambucil (Cbl) were developed.

Photocaging of Single and Dual (Similar or Different) Carboxylic and Amino Acids by Acetyl Carbazole and its Application as Dual Drug Delivery in Cancer Therapy

A new fluorescent photoremovable protecting group (FPRPG) based on acetylcarbazole framework has been explored for the first time release of single and dual (similar or different) substrates from single chromophore. Mechanistic studies of the photorelease process revealed that photorelease of two (similar or different) substrates from acetyl carbazole proceeds via a stepwise pathway. Further, we constructed photoresponsive dual drug delivery system (DDS) to release two different anticancer drugs (caffeic acid and chlorambucil, 1 equiv each). In vitro study reveals that our DDS exhibit excellent properties like biocompatibility, cellular uptake, and photoregulated dual drug release.