Collagen-coated polycaprolactone microparticles as a controlled drug delivery system

OBJECTIVE

Polycaprolactone (PCL) microparticles coated with acetylated collagen have been assessed for use as a controlled drug delivery system.

METHOD

The surface morphology, drug encapsulation and release profile of PCL microparticles and collagen-coated PCL microparticles containing doxycycline hydrochloride (DH) have been investigated in order to develop a controlled release system which would in addition act as a scaffold for cell attachment. PCL microparticles were prepared by emulsion solvent evaporation technique and loaded with DH. Since the encapsulation was found to be low, PCL microparticles were coated with acetylated collagen containing DH, to increase the drug availability. Collagen was modified by acetylation to shift its isoelectric point and to have acetylated collagen solution at pH 7.0. The microparticles were characterized using a scanning electron microscope (SEM) and the in vitro drug release profile was determined using HPLC.

RESULTS

Uniform sized (approximately 1000 nm) PCL microparticles were prepared using 4% PVA in the external water phase. Acetylated collagen at pH 7.0 was coated onto the PCL microparticles. This resulted in microparticles of uniform size at neutral pH. PCL acts as a support for collagen which acts as a scaffold for cell attachment. In vitro drug release studies show that collagen-coated PCL microparticle is a promising candidate for controlled drug delivery system having release duration of over 10 days. In vitro fibroblast culture studies reveal that collagen is a good substrate for cell attachment and would provide a stable environment for cell proliferation and regeneration. Thus, this system would be ideal for a short-term drug delivery to create an aseptic environment where cells can adhere and proliferate to regenerate the site.

Fish Scales as Potential Substrate for Production of Alkaline Protease and Amino Acid Rich Aqua Hydrolyzate by Bacillus altitudinis GVC11

Fish processing industries generate large quantities of fish scales as processing waste, if not treated leading to environmental pollution. Fish scales are hard to degrade, hence cause difficulty in waste management. In this context present study was made to utilize fish scales as substrate for the production of alkaline protease by Bacillus altitudinis GVC11 and subsequently amino acid rich aqua hydrolyzate. B. altitudinis GVC11 efficiently utilized five types of fish scales as substrates and produced maximum alkaline protease using Labeo rohita (28,150 U/mL) followed by Catla catla (23,320 U/mL) at 48 h and Cyprinus carpio (17,146 U/mL) Mugil cephalus (18,917 U/mL), Cirrhinus mrigala (12,430 U/mL) at 72 h. The HPLC analysis of protein hydrolyzate obtained after fermentation was enriched in essential amino acids, leucine, isoleucine, phenylalanine, lysine and non-essential amino acids, tyrosine, arginine and cysteine which can be used as animal feed supplement and organic fertilizer.

Isolation of a cDNA clone (PcSrp) encoding serine-rich-protein from Porteresia coarctata T. and its expression in yeast and finger millet (Eleusine coracana L.) affording salt tolerance

A 1.4 Kb cDNA clone encoding a serine-rich protein has been isolated from the cDNA library of salt stressed roots of Porteresia coarctata, and designated as P. coarctata serine-rich-protein (PcSrp) encoding gene. Northern analysis and in situ mRNA hybridization revealed the expression of PcSrp in the salt stressed roots and rhizome of P. coarctata. However, no such expression was seen in the salt stressed leaves and in the unstressed tissues of root, rhizome and leaf, indicating that PcSrp is under the control of a salt-inducible tissue-specific promoter. In yeast, the PcSrp conferred increased NaCl tolerance, implicating its role in salinity tolerance at cellular level. Further, PcSrp was cloned downstream to rice Actin-1 promoter and introduced into finger millet through particle-inflow-gun method. Transgenic plants expressing PcSrp were able to grow to maturity and set seed under 250 mM NaCl stress. The untransformed control plants by contrast failed to survive under similar salt stress. The stressed roots of transgenic plants invariably accumulated higher Na(+) and K(+) ion contents compared to roots of untransformed plants; whereas, shoots of transgenics accumulated lower levels of both the ions than that of untransformed plants under identical stress, clearly suggesting the involvement of PcSrp in ion homeostasis contributing to salt tolerance.

Calculation of the photodetachment cross sections of the HCN- and HNC- dipole-bound anions as described by a one-electron Drude model

The Drude model for treating the interaction of excess electrons with polar molecules is extended to calculate continuum functions and to evaluate photodetachment cross sections. The approach is applied to calculate the cross sections for photodetachment of dipole-bound electrons from HCN(-) and HNC(-). In addition, an adiabatic model separating the angular and radial degrees of freedom of the excess electron is introduced and shown to account in a qualitative manner for the cross sections.

Dosimetric analysis and comparison of IMRT and HDR brachytherapy in treatment of localized prostate cancer

Radical radiotherapy is one of the options for the management of prostate cancer. In external beam therapy, 3D conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT) are the options for delivery of increased radiation dose, as vital organs are very close to the prostate and a higher dose to these structures leads to an increased toxicity. In brachytherapy, low dose rate brachytherapy with permanent implant of radioactive seeds and high dose rate brachytherapy (HDR) with remote after loaders are available. A dosimetric analysis has been made on IMRT and HDR brachytherapy plans. Ten cases from each IMRT and HDR brachytherapy have been taken for the study. The analysis includes comparison of conformity and homogeneity indices, D100, D95, D90, D80, D50, D10 and D5 of the target. For the organs at risk (OAR), namely rectum and bladder, V100, V90 and V50 are compared. In HDR brachytherapy, the doses to 1 cc and 0.1 cc of urethra have also been studied. Since a very high dose surrounds the source, the 300% dose volumes in the target and within the catheters are also studied in two plans, to estimate the actual volume of target receiving dose over 300%. This study shows that the prescribed dose covers 93 and 92% of the target volume in IMRT and HDR brachytherapy respectively. HDR brachytherapy delivers a much lesser dose to OAR, compared to the IMRT. For rectum, the V50 in IMRT is 34.0cc whilst it is 7.5cc in HDR brachytherapy. With the graphic optimization tool in HDR brachytherapy planning, the dose to urethra could be kept within 120% of the target dose. Hence it is concluded that HDR brachytherapy may be the choice of treatment for cancer of prostate in the early stage.

Facile hydrothermal bio-synthesis of cellulose acetate templated CuS nanorods like fibres: antibacterial, cytotoxicity effects and DNA cleavage properties against A549 lung cancer cells

In this research, the hydrothermal method was used for synthesising cellulose acetate (CA) templated nanorods like CuS fibres using vegetable extract (Brassica oleracea var. italica). These extracts act as a reducing agent in the presence of CA. Surprisingly, when the same reaction was carried out in the absence of CA and broccoli extract, structural morphology disappeared and was found as agglomerated. In the presence of cellulose templated extract mediated CuS has revealed as nanorods like fibres and was confirmed by field emission scanning electron microscope analysis. Their crystallinity property of CuS nanoparticles (NPs) and cellulose templated biosynthesised CuS NPs was analysed and compared using X-ray diffraction technique. The biological activities of the obtained product were examined for antibacterial assessment against two bacterial strains that include two-gram negative strains (E.Coli and S. aureus). The nanostructured product found to exhibit excellent antibacterial agent against all the strains. Biosynthesised nanostructure showed its efficacy against A549 lung cancer cells which might attribute to a larger surface to volume ratio of nanorods like fibres. The authors observation suggest that CuS nanorods like fibres can significantly reduce the cell growth with IC₅₀ value of 31.2 μg/ml.

Biochemical predictors for Sars-Cov-2 severity

It is of interest to assess the inflammatory marker profile in SARS-CoV-2 patients and to correlate the levels of systemic inflammatory biomarkers such as neutrophil-to-lymphocyte ratio (NLR), C-Reactive Protein CRP, Ferritin, Creatine kinase (CK), Lactate dehydrogenase (LDH) and liver function analytes total serum proteins, albumin, total bilirubin, direct bilirubin, alkaline phosphatase, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) with the severity of SARS-CoV-2 infections. A total of 1000 COVID-19 positive patient's data were collected. Laboratory assessments consisted of NLR (neutrophil-lymphocyte ratio) by cell counter, C Reactive Protein (CRP) by immunoturbidimetry, Ferritin by electrochemiluminescence (ECLIA) and Creatine Kinase (CK), Lactate Dehydrogenase (LDH), Alkaline phosphatase (ALP), Aspartate aminotransferase (AST), Alanine aminotransferase (ALT), Total Bilirubin, Direct Bilirubin, Total Protein and Albumin by spectrophotometry. The mean plasma CRP levels, NLR, ferritin, CK and LDH levels were higher in severe cases than in non-severe cases, and the difference was statistically significant (p<0.05). All liver function tests such as the total and direct bilirubin, AST, ALT, ALP, total protein and albumin were higher in severe patients than non-severe patients and the difference was statistically significant (p<0.05). Data indicate that NLR, CRP, Ferritin, CK, LDH and liver function analytes have a crucial role as prognostic markers for SARS-CoV-2 infections and hence should be routinely recommended for risk assessment and stratification of the patients to reduce the associated morbidity and mortality.

Occurrence of spintronics behaviour (half-metallicity, spin gapless semiconductor and bipolar magnetic semiconductor) depending on the location of oxygen vacancies in BiFe0.83Ni0.17O3

The current communication signifies the effect of oxygen vacancies (OVs) both qualitatively and quantitatively in multiferroic BiFe_0.83Ni_0.17O₃ by an in-depth atomic-level investigation of its electronic structure and magnetization properties, and these materials have a variety of applications in spintronics, optoelectronics, sensors and solar energy devices. Depending on the precise location of OVs, all the three types of spintronic material namely half-metallic, spin gapless semiconductor and bipolar magnetic conductor have been established in a single material for the first time and both super-exchange and double-exchange interactions are possible in accordance with the precise location of OVs. We have also calculated the vacancy formation energies to predict their thermodynamic stabilities. These results can highlight the impact and importance of OVs that can alter the multiferroic properties of materials.

(5S,6S,10R)-10-(2,4-Dichloro-phen-yl)-14-[(E)-(2,4-dichloro-phen-yl)methyl-idene]-3,9-diphenyl-12-[(R)-1-phenyl-ethyl]-1,4,7-trioxa-2,8,12-triaza-dispiro-[4.0.4.4]tetra-deca-2,8-diene

The asymmetric unit of the title compound, C(41)H(31)Cl(4)N(3)O(3), contains two independent mol-ecules with almost identical geometries. The piperidine ring adopts a chair conformation in both mol-ecules, and the dihydro-isoxazole rings adopt envelope conformations. The crystal structure is stabilized by C-H⋯N hydrogen bonds and C-H⋯π inter-actions.