Cobalt–carbon/silica nanocomposites prepared by pyrolysis of a cobalt 2,2′-bipyridine terephthalate complex for remediation of cationic dyes

Recently, carbon nanostructures have attracted interest because of their unique properties and interesting applications. Here, CoC@SiO₂-850 (3) and CoC@SiO₂-600 (4) cobalt–carbon/silica nanocomposites were prepared by solid-state pyrolysis of anthracene with Co(tph)(2,2′-bipy)·4H₂O (1) complex in the presence of silica at 850 and 600 °C, respectively, where 2,2′-bipy is 2,2′-bipyridine and tph is the terephthalate dianion. Moreover, Co(μ-tph)(2,2′-bipy) (2) was isolated and its X-ray structure indicated that cobalt(ii) has a distorted trigonal prismatic coordination geometry. 2 is a metal–organic framework consisting of one-dimensional zigzag chains within a porous grid network. 3 and 4 consist of cobalt(0)/cobalt oxide nanoparticles with a graphitic shell and carbon nanotubes embedded in the silica matrix. They were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), powder X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). XPS revealed that the nanocomposites are functionalized with oxygen-containing groups, such as carboxylic acid groups. In addition, the presence of metallic cobalt nanoparticles embedded in graphitized carbon was verified by XRD and TEM. The efficiency of 3 for adsorption of crystal violet (CV) dye was investigated by batch and column experiments. At 25 °C, the Langmuir adsorption capacity of 3 for CV was 214.2 mg g⁻¹ and the fixed-bed column capacity was 36.3 mg g⁻¹. The adsorption data were well fitted by the Freundlich isotherm and pseudo-second-order kinetic model. The adsorption process was spontaneous and endothermic.

A cobalt–carbon@silica nanocomposite was synthesized from a cobalt 2,2′-bipyridine terephthalate complex and its adsorption behavior towards crystal violet dye was tested using batch and column techniques.     

Antihyperglycaemic effect of Casearia esculenta root extracts in streptozotocin-induced diabetic rats

The present study was carried out to evaluate the antihyperglycaemic effect of Casearia esculenta root extract and to study the activities of liver hexokinase and gluconeogenic enzymes such as glucose-6-phosphatase and fructose-1,6-bisphosphatase in liver and kidney of normal and streptozotocin-induced diabetic rats. Oral administration of aqueous extract of root (300 mg/kg body weight) for 45 days resulted in a significant reduction in blood glucose from 250.79 +/- 12.65 to 135.70 +/- 8.90 and in a decrease in the activities of glucose-6-phosphatase and fructose-1,6-bishosphatase and an increase in the activity of liver hexokinase. However, in the case of 200 mg/kg body weight of extract, less activity was observed. The study clearly shows that the root extract of C. esculenta possesses potent antihyperglycaemic activity but weaker than that of glibenclamide.     

Influence of Casearia esculenta root extract on glycoprotein components in streptozotocin diabetic rats

The present study was aimed to evaluate the role of the indigenous antidiabetic medicinal plant Casearia esculenta on glycoprotein components in streptozotocin-induced diabetic rats in plasma, liver, kidney and cardiac tissues. Streptozotocin injection (50 mg/kg body weight) caused massive elevation of glycoprotein components such as hexose, hexosamine, sialic acid and fucose in plasma and tissues of diabetic control and experimental animals. Oral administration of C. esculenta root extract (200 and 300 mg/kg body weight) for 45 days significantly reverted the hexose, hexosamine, sialic acid and fucose levels to near normal values. These results suggest a normalizing effect of C. esculenta on glycoprotein components in STZ diabetic rats.     

Hypolipidaemic effect of Casearia esculenta root extracts in streptozotocin-induced diabetic rats

The hypolipidaemic effect of an aqueous extract of Casearia esculenta root, an indigenous antidiabetic medicine popularly used in rural South India was investigated. Administration of the extract of C. esculenta (200 and 300 mg/kg body wt.) for 45 days resulted in significant reduction in serum and tissue cholesterol, phospholipids, free fatty acids and triglycerides in streptozotocin (STZ) diabetic rats. In addition to that, significant (p < 0.05) decrease in high density lipoprotein (HDL) whereas significant increase (p < 0.05) in low density lipoprotein (LDL) and very low density lipoprotein (VLDL) were observed in STZ diabetic rats, which was normalized after 45 days of C. esculenta root extract treatment. The root extract at dose of 300 mg/kg body wt. showed much significant hypolipidaemic effects than the dose of 200 mg/kg body weight.     

Potential for hepatitis C transmission among non-needle/syringe sharing Sheffield drug injectors through the sharing of drug preparation paraphernalia

This study aimed to investigate possible means by which hepatitis C virus (HCV) might be transmitted between drug injecting individuals without the sharing of needles and syringes. A questionnaire-based survey of 143 (out of 287) attendees was conducted at an Infectious Diseases Unit-based HCV clinic. Those patients (all of whom were positive for antibodies to HCV) who asked about risk activities and those that admitted to a history of recreational drug injecting were questioned in detail about their past and current drug preparation practices. Ten per cent denied any history of needle and/or syringe sharing and had no other apparent source of their HCV infection, but instead admitted to having shared drug preparation eqiupment. The existence among drug injectors of such practices with the potential to transmit blood borne viruses is important as it may explain how HCV, which is capable of being spread via very small quantities of blood, can be passed between drug injecting individuals who might otherwise never come into contact with another drug injector's blood. Clinical and public health messages regarding the prevention of the spread of HCV may need to be revised and strengthened.     

A perfluoropolyether corneal inlay for the correction of refractive error

This study assessed the long-term biological response of a perfluoropolyether-based polymer developed as a corneal inlay to correct refractive error. The polymer formulation met chemical and physical specifications and was non-cytotoxic when tested using standard in vitro techniques. It was cast into small microporous membranes that were implanted as inlays into corneas of rabbits (n?=?5) and unsighted humans (n?=?5?+?1 surgical control) which were monitored for up to 23 and 48 months respectively. Overall, the inlays were well tolerated during study period with the corneas remaining clear and holding a normal tear film and with no increased vascularisation or redness recorded. Inlays in three human corneas continued past 48 months without sequelae. Inlays in two human corneas were removed early due to small, focal erosions developing 5 and 24 months post-implantation. Polymer inlays maintained their integrity and corneal position for the study duration although the optical clarity of the inlays reduced slowly with time. Inlays induced corneal curvature changes in human subjects that showed stability with time and the refractive effect was reversed when the inlay was removed. Outcomes showed the potential of a perfluoropolyether inlay as a biologically acceptable corneal implant with which to provide stable correction of refractive error.     

Additive Effect of Plasma Rich in Growth Factors With Guided Tissue Regeneration in Treatment of Intrabony Defects in Patients With Chronic Periodontitis: A Split‐Mouth Randomized Controlled Clinical Trial

Background: Periodontal regeneration can be defined as complete restoration of lost periodontal tissues to their original architecture and function. A variety of treatment modalities have been proposed to achieve it. Plasma rich in growth factors (PRGF) is a concentrated suspension of growth factors that promotes restoration of lost periodontal tissues. The objective of the present study is to assess the effect of PRGF associated with guided tissue regeneration (GTR) versus GTR only in the treatment of intrabony defects (IBDs) in patients with chronic periodontitis (CP). Methods: Patients with CP (n = 14) with 42 contralateral 2‐ and 3‐walled defects were randomly assigned to test (PRGF+GTR) and control (GTR alone) treatment groups. Clinical and radiographic assessments performed at baseline and after 6 months were: 1) gingival index (GI), 2) probing depth (PD), 3) clinical attachment level (CAL), 4) radiologic defect depth, and 5) bone fill. Results: Comparison of parameters measured at baseline and after 6 months showed mean PD reduction of 3.37 ± 1.62 mm in the control group (P <0.001) and 4.13 ± 1.59 mm in the test group (P <0.001). There was a significant difference in mean change in CAL (P <0.001) in the control group (5.42 ± 1.99) and the test group (5.99 ± 1.77). Mean change in GI was 1.89 ± 0.32 and 1.68 ± 0.58 in the control group and test group, respectively, and the difference was statistically significant (P <0.001). When compared between groups, clinical parameters did not show any statistically significant variations. Mean radiographic bone fill was 1.06 ± 0.81 and 1.0 ± 0.97 in the control group and test group, respectively. However, the difference was not statistically significant. Conclusions: PRGF with GTR, as well as GTR alone, was effective in improving clinical and radiographic parameters of patients with CP at the 6‐month follow‐up. There was no additive effect of PRGF when used along with GTR in the treatment of IBDs in patients with CP in terms of both clinical and radiologic outcomes.