Tamilnadia uliginosa (Retz) Tirveng and Sastre: Potential Application from Traditional Remedies to Modern Therapeutics

Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Tamilnadia uliginosa (Retz) Tirveng and Sastre (Rubiaceae) is a small edible medicinal plant utilized in...     

Synthesis of nanoscale CuO via precursor method and its application in the catalytic epoxidation of styrene

Nanoscale CuO with diameters in the range of 7–8 nm has been synthesized via a two-step precipitation–calcination method using copper(ii) isonicotinate tetrahydrate as the precursor. The first step involves the room temperature stirring of an alkaline ethanolic solution of the precursor which gives a non-crystalline CuO species, while the second step involves the calcination of the product of the first step at 180 °C to form nanocrystalline CuO which has been characterized by PXRD, TEM, SEM, H₂-TPR and Raman spectroscopy, etc. The CuO material has shown excellent catalytic activity in the oxidation of styrene using TBHP as the oxidizing agent leading to complete styrene conversion with more than 95% styrene oxide selectivity at the end of 6 h. The oxide catalyst can be reused for at least 6 successive runs without significant loss in activity.

Nanoscale CuO with diameters in the range of 7–8 nm has been synthesized via a two-step precipitation–calcination method using copper(ii) isonicotinate tetrahydrate as the precursor.     

Polycarboxylic acid nanoparticles for ophthalmic drug delivery: an ex vivo evaluation with human cornea

In ophthalmic drug delivery, a major problem is retaining an adequate concentration of a therapeutic agent in the pre-corneal area. Polycarboxylic acid carriers such as polyacrylic acid and polyitaconic acid in sub-colloidal, nanoparticulate hydrogel form have a strong potential for sustained release of a drug in ocular delivery. Formulations have been prepared of brimonidine loaded in polycarboxylic (polyacrylic and polyitaconic) acid nanoparticles for potential ophthalmic delivery. These particles were prepared by a reverse micro-emulsion polymerization technique with sizes in the range of 50 nm. The loading efficiencies of the drug brimonidine in the particles were shown to be between 80-85% for polyacrylic acid nanoparticles and between 65-70% for polyitaconic nanoparticles. The loading efficiency was also found to be pH dependent. In a preliminary biocompatibility test, human corneal epithelial cells incubated with polyacrylic acid nanoparticles were found to retain their viability, whereas polyitaconic acid nanoparticles were found to be toxic. Two-photon laser scanning microscopic studies of the fluorescently labelled polyacrylic acid nanoparticles and human cornea shows that they are adhesive on the corneal surface. The polyacrylic acid nanoparticles demonstrated a controlled release of the opthalmological drug (Brimonidine) through the human cornea as compared to that of the commercial formulation, Alphagan.     

rs2230201 polymorphism may dictate complement C3 levels and response to treatment in chronic hepatitis C patients

The basis of response of chronic hepatitis C (CHC) patients to treatment is still unclear, and there may be many other factors which influence treatment outcome other than the existing ones. The serum concentration of C3 closely reflects the total complement activity, and individuals affected by C3 deficiency suffer from recurrent pyogenic infections. This study aims to find out relationship between levels of C3 in serum and its functional SNPs with response to treatment. The study included 132 CHC patients of which 48 received Pegylated IFN+Ribavirin and 81 controls. C3 levels and its three known functional SNP's genotyped by ELISA and SSP PCR, respectively. C3 Level of the healthy group was significantly higher (88.5 ± 19 mg/dL) when compared to CHC group (56 ± 18 mg/dL; P < 0.001). Thirty‐three of 36 responders were rs2230201 CC genotype carriers, whereas 9 of 12 nonresponders were non‐CC genotype. The ‘C’ allele of rs2230201 was found to be associated with increased serum C3 levels when compared to other genotypes in healthy group, whereas CT genotype was associated with lowered serum C3 in CHC group. A serum C3 value of <53 mg/dL was predictive of SVR with sensitivity 63.89% and specificity 66.67%. The study supports the observation that rs2230201 ‘C’ allele is associated with increase of serum C3 levels when compared to ‘T’ allele which may confer advantage in attaining SVR when present in homozygous condition. The study suggests that patients with serum C3 value <53 mg/dL and non‐CC genotypes may not respond to treatment.     

Reinnervation of sweat glands in the rat hind paw following peripheral nerve injury

Electrophysiological experiments have been carried out to investigate the time course and extent of sweat gland reinnervation in the rat hind paw. The first evidence of functional reinnervation after nerve transection was obtained at 12 weeks, when the extent of innervation was 20% of that measured in control animals. By 20 weeks, reinnervation had reached almost 50% of control values but then there was no further improvement up to 52 weeks. These results are comparable to those for skin reinnervation by polymodal nociceptor afferents.     

Emerging nanopharmaceuticals

A budding interest in nanopharmaceuticals has generated a number of advancements throughout recent years with a focus on engineering novel applications. Nanotechnology also offers the ability to detect diseases at much earlier stages, such as finding hidden or overt metastatic colonies often seen in patients diagnosed with breast, lung, colon, prostate, and ovarian cancer. Diagnostic applications could build upon conventional procedures using nanoparticles, such as colloidal gold, iron oxide crystals, and quantum dots. Additionally, diseases may be managed by multifunctional agents encompassing both imaging and therapeutic capabilities, thus allowing simultaneous monitoring and treatment. A detailed evaluation of each formulation is essential to expand our current nanopharmaceutical repertoire. However, the safety and long-term effects of nanoformulations must not be overlooked. This review will provide a brief discussion of the major nanopharmaceutical formulations as well as the impact of nanotechnology into the future.     

Success of regeneration of peripheral nerve axons in rats after injury at different postnatal ages

Electrophysiological experiment have been carried out on rats to see if the age at which a peripheral nerve injury occurs influences the success of regeneration. The assessment was made on the basis of two measures of peripheral nerve regeneration; the extent to which axons manage to grow across the injury site and into the distal stump, and their ability to resupply cutaneous structures with functional endings. Regeneration after nerve transection of both myelinated and unmyelinated axons was studied. The results showed that, apart from rats injured when 2 weeks old, the age at which injury occurred, over the range 4–40 weeks, had little bearing on the overall success of skin reinnervation. The 2-week-old rats showed significantly poorer recovery.     

Surgical Repair of Submitral Aneurysm: A Case Report

Aim: External, non‐restrictive, macro‐porous stents prevent neointima formation in porcine vein grafts and have been proposed as a therapeutic approach to the prevention of late vein graft failure. Since these stents are non‐biodegradable and therefore may elicit deleterious long‐term, inflammatory, infective and mechanical complications the effect of external macro‐porous biodegradable (polyglactin) stents on neointimal and medial thickening in porcine vein grafts was investigated. Methods: Bilateral vein saphenous vein‐carotid artery interposition grafting was performed in Large White pigs (22–36 kg, n = 6 ) with external placement of 8 mm diameter polyglactin stents on one side, the contralateral side acting as a control. One month after surgery, graft wall dimensions were measured on histological sections using computer‐aided planimetry and immunocytochemistry undertaken for selected parameters. Results: Polyglactin stents significantly reduced medial thickening compared to the All grafts were patent at explantation. Intimal thickness was significantly lower (p < 0.05) in the stented grafts (0.11 ± 0.01 mm) compared to the unstented controls (0.18 ± 0.01 mm) . Similarly, medial thickness was significantly lower (p < 0.05) in the stented grafts (0.24 ± 0.03 mm) compared to the unstented controls (0.43 ± 0.04 mm) mm. Grafts externally supported with polyglactin had a pronounced increase in inflammatory cells (in particular, giant cells) around the biodegradable stent compared to both unstented controls and previously studied Dacron stented grafts. The space between graft and stent had become organised into a neo‐adventitia with abundant microvessels which stained positively for VEGF and lectin (markers of micorvessels and endothelial cells). Conclusions: An over‐size biodegradable stent reduces medial thickening, a component of late vein graft failure in experimental grafts. If subsequent studies confirm the preservation of this beneficial effect when the stent biodegrades completely, this form of stent may have an advantage over permanent stent material in the clinical use of external stenting to prevent vein graft thickening and failure.     

Novel nanoparticles for the delivery of recombinant hepatitis B vaccine

We describe the use of methoxypolyethylene glycol-poly(lactide-co-glycolide) nanoparticles as a delivery system for recombinant hepatitis B surface antigen (HBsAg). Evaluation of the stability and release kinetics of nanoencapsulated HBsAg in vitro in serum revealed an initial burst effect and a subsequent slower release of the antigen. Importantly the antigenicity was not destroyed by the encapsulation process, because upon release it was able to react with an anti-HBs antibody. Bone marrow-derived dendritic cells showed efficient uptake of the nanoparticle vaccine as visualized by confocal imaging. To determine whether nano-encapsulated HBsAg was capable of eliciting an immune response in the absence of an adjuvant, mice were immunized with the nanoparticle vaccine or with nonencapsulated recombinant HBsAg. In mice immunized with the nanoparticle vaccine, anti-HBs antibodies were detected at significantly earlier time points than in mice immunized with the nonencapsulated recombinant HBsAg.