Regeneration and modification of cellulose acetate from cigarette waste: Biomedical potential by encapsulation of tetracycline hydrochloride.

Cigarette waste are pervasive litter on Earth, posing a major threat to organisms and ecosystems. However, these waste contain cellulose acetate (CA) and can be recycled, transforming into raw materials for new products. Polymers like CA can be used in biomedical applications as drug carriers and scaffolds for drug release. In this study, cigarette filters waste was collected, recycled and used for fabricating the nanofibrous membrane of cellulose acetate nanofibers (CFCA) through electrospinning technique. Tetracycline hydrochloride (TC) was encapsulated in the nanofibers to prevent bacterial infections. Various analyses were conducted: Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction Analysis (XRD) and Thermogravimetric analysis (TGA). CA and CFCA exhibited high water uptake properties and exhibited similar breaking stress and strain values. Both CA and CFCA effectively acted as stable drug carriers, with sustained in vitro drug release. Antibacterial activity was demonstrated by the drug-loaded CA and CFCA nanofibers against, Gram-positive bacteria Staphylococcus aureus and Gram-negative bacteria Escherichia coli. Based on their cytotoxicity evaluations on mouse fibroblast cells (L929), CA and CFCA fibrous mats demonstrated no cytotoxicity and similar cell viability results. Consequently, the TC-loaded nanofibers made from CA and CFCA exhibited suitable properties for wound healing applications.

The vespid fauna of Pakistan.

This study provides the first annotated check list of the Vespidae of Pakistan. It is based on the National Insect Museum collection and various studies in Pakistan. Among 105 identified taxa, 77 species and 28 subspecies are recorded in the four subfamilies Eumeninae, Masarinae, Polistinae and Vespinae. Three new records for the fauna of Pakistan are added, namely Anterhynchium mellyi, Antepipona ovalis and Eumenes coronatus coronatus. Among the total, 12 species/subspecies are endemic to Pakistan, namely Ancistrocerus pakistanus, Antepipona luteipes, Antodynerus flavescens karachiensis, Celonites nursei, Cyrtolabulus karachiensis, Eustenancistrocerus (Parastenancistrocerus) baluchistanensis, Katamenes dimidiatus watsoni, Knemodynerus lahorensis, Leptochilus (Neoleptochilus) hina, Leptochilus (Neoleptochilus) mirificus, Leptochilus (Neoleptochilus) umerolatus and Tachyancistrocerus pakistanus. Antepipona varentzowi (Morawitz, 1896) and Polistes rothneyi quatei van der Vecht, 1968 were incorrectly reported from Pakistan.

The hawkmoth fauna of Pakistan (Lepidoptera: Sphingidae).

This study represents the first complete modern account of the Sphingidae of Pakistan and takes the form of an annotated checklist, based on several national collections and those of a number of individuals. Of the 60 species and subspecies found, 14 are new records to the fauna of Pakistan, namely Agnosia orneus, Langia zenzeroides subsp. zenzeroides, Polyptychus trilineatus subsp. trilineatus, Dolbina inexacta, Ambulyx sericeipennis subsp. sericeipennis, Thamnoecha uniformis, Macroglossum belis, Macroglossum stellatarum, Cechetra scotti, Hippotion boerhaviae, Hyles euphorbiae subsp. euphorbiae, Rhagastis olivacea, Rethera brandti subsp. euteles and Theretra latreillii subsp. lucasii. Anambulyx elwesi subsp. kitchingi and Clanis deucalion subsp. thomaswitti are not recognised as valid subspecies and are synonymized with their respective nominotypical subspecies. An additional list is given of 30 taxa which may yet be found in Pakistan as they are present in neighbouring countries close to the border. Of the species/subspecies found, 24 are part of the Palaearctic fauna, 27 are part of the Oriental fauna and nine are Palaeo-Oriental/Palaeotropical. This reconfirms the transitional biogeographical position of the Pakistan fauna.