Reduced graphene oxide-loaded nanocomposite scaffolds for enhancing angiogenesis in tissue engineering applications

Tissue engineering combines cells, scaffolds and signalling molecules to synthesize tissues in vitro. However, the lack of a functioning vascular network severely limits the effective size of a tissue-engineered construct. In this work, we have assessed the potential of reduced graphene oxide (rGO), a non-protein pro-angiogenic moiety, for enhancing angiogenesis in tissue engineering applications. Polyvinyl alcohol/carboxymethyl cellulose (PVA/CMC) scaffolds loaded with different concentrations of rGO nanoparticles were synthesized via lyophilization. Characterization of these scaffolds showed that the rGO-loaded scaffolds retained the thermal and physical properties (swelling, porosity and in vitro biodegradation) of pure PVA/CMC scaffolds. In vitro cytotoxicity studies, using three different cell lines, confirmed that the scaffolds are biocompatible. The scaffolds containing 0.005 and 0.0075% rGO enhanced the proliferation of endothelial cells (EA.hy926) in vitro. In vivo studies using the chick chorioallantoic membrane model showed that the presence of rGO in the PVA/CMC scaffolds significantly enhanced angiogenesis and arteriogenesis.

Gentiana lutea exerts anti-atherosclerotic effects by preventing endothelial inflammation and smooth muscle cell migration

BACKGROUND AND AIMS

Studies suggest that Gentiana lutea (GL), and its component isovitexin, may exhibit anti-atherosclerotic properties. In this study we sought to investigate the protective mechanism of GL aqueous root extract and isovitexin on endothelial inflammation, smooth muscle cell migation, and on the onset and progression of atherosclerosis in streptozotocin (STZ)-induced diabetic rats.

METHODS AND RESULTS

Our results show that both GL extract and isovitexin, block leukocyte adhesion and generation of reactive oxygen species in human umbilical vein endothelial cells (HUVECs) and rat aortic smooth muscle cells (RASMCs), following TNF-alpha and platelet derived growth factor-BB (PDGF-BB) challenges respectively. Both the extract and isovitexin blocked TNF-α induced expression of ICAM-1 and VCAM-1 in HUVECs. PDGF-BB induced migration of RASMCs and phospholipase C-γ activation, were also abrogated by GL extract and isovitexin. Fura-2 based ratiometric measurements demonstrated that, both the extact, and isovitexin, inhibit PDGF-BB mediated intracellular calcium rise in RASMCs. Supplementation of regular diet with 2% GL root powder for STZ rats, reduced total cholesterol in blood. Oil Red O staining demonstrated decreased lipid accumulation in aortic wall of diabetic animals upon treatment with GL. Medial thickness and deposition of collagen in the aortic segment of diabetic rats were also reduced upon supplementation. Immunohistochemistry demonstrated reduced expression of vascular cell adhesion molecule-1 (VCAM-1), inducible nitric oxide synthase (iNOS), and vascular endothelial cadherin (VE-cadherin) in aortic segments of diabetic rats following GL treatment.

CONCLUSIONS

Thus, our results support that GL root extract/powder and isovitexin exhibit anti-atherosclerotic activities.

Quantitative Mueller matrix fluorescence spectroscopy for precancer detection

Quantitative fluorescence spectroscopic Mueller matrix measurements from the connective tissue regions of human cervical tissue reveal intriguing fluorescence diattenuation and polarizance effects. Interestingly, the estimated fluorescence linear diattenuation and polarizance parameters were considerably reduced in the precancerous tissues as compared to the normal ones. These polarimetry effects of the autofluorescence were found to originate from anisotropically organized collagen molecular structures present in the connective tissues. Consequently, the reduction of the magnitude of these polarimetric parameters at higher grades of precancer was attributed to the loss of anisotropic organization of collagen, which was also confirmed by control experiments. These results indicate that fluorescence spectral diattenuation and polarizance parameters may serve as potentially useful diagnostic metrics.

Sustained release of Zn from zinc sulfide nanoparticles (ZnS NPs) amplified the bioaccessibility of Zn in soil: Adsorption dynamics and dissolution kinetics

Controlled-release micronutrient supplementation to provide better bioavailable zinc (Zn) under alkaline soil conditions is a concept of commercial pertinence for sustainable agriculture. High pH stable nano-scaled ZnS is the material under study in the present investigation where the adsorption dynamics and dissolution kinetics of sono-chemically synthesized zinc sulfide nanoparticles (ZnS NPs) were evaluated in comparison to ZnSO4 in Lufa 2.2 soil for supplementation of Zn. The mechanism of adsorption of ZnS NPs and ZnSO4 onto Lufa 2.2 soil was well explained by fitting into the Freundlich adsorption model and pseudo-second order equation. ZnS NPs reflected the stronger ability to get adsorbed on the Lufa 2.2 soil as compared to metal ions, due to higher surface reactivity of NPs and higher Kf value (0.557) than ZnSO4 (0.463). Time relevant enhancement in extractability of Zn from ZnS NPs amended soil and diminution in extractability of Zn from ZnSO4 spiked soil was observed in bioavailability studies. The increased labile pool of Zn from ZnS NPs amended soil over time was due to their slow dissolution in soil and could be adjusted to consider as "sustained released ZnS NPs". Dissolution of ZnS nanoparticles (NPs) in Lufa 2.2 soil adhered to the first-order extraction model, exhibiting extended half-lives of 27.72 days (low dose) and 28.87 days (high dose). This supported prolonged stability, increased reactivity, and reduced ecological risk compared to conventional Zn salt fertilizers, promoting enhanced crop productivity.

Effect of artesunate based combination therapy with homeopathic medicine china on liver and kidney of Plasmodium berghei infected mice

Present study has been undertaken to evaluate antimalarial potential and safety of artesunate based combination therapy with homeopathic medicine china (ϕ/30 potency) against Plasmodium berghei (NK-65), a lethal rodent malaria parasite. In combination therapy, the oral administration of artesunate (100 mg/kg) + china ϕ/30 proved to be highly efficacious as it completely cleared the blood stage infection. During the follow up period up to day 28, no recrudescence was observed and the survival rate was 100 %. Combination did not disturb the normal functioning of liver and kidney, as evident from the normal activity of ALP (190.5 ± 0.2 and 174.2 ± 9.12 IU/l), level of bilirubin (0.6 ± 0.33 and 0.73 ± 0.1 mg/dl), urea (28 ± 0.51 and 29.1 ± 0.03 mg/dl) and creatinine (0.9 ± 0.62 and 1.1 ± 0.1 mg/dl) in serum of treated mice on day 7 and 28 respectively. Present study points to better efficacy of china as an alternative drug partner in combination to enhance antimalarial efficacy of artesunate without affecting the liver and kidney functions of P. berghei infected BALB/c mice.

Development and Validation of HPTLC Method for Estimation of Tenoxicam and its Formulations

A simple, precise, accurate and rapid high performance thin layer chromatographic method has been developed and validated for the estimation of tenoxicam in the microemulsion gels. Tenoxicam was chromatographed on silica gel 60 F(254) TLC plate, as a stationary phase. The mobile phase was toluene: ethyl acetate: formic acid (6:4:0.3 v/v/v), which gave a dense and compact spot of tenoxicam with a R(f) value of 0.38±0.03. The quantification was carried out at 379 nm. The method was validated in terms of linearity, accuracy, precision and specificity. To justify the suitability, accuracy and precision of the proposed method, recovery studies were performed at three concentration levels. Statistical analysis proved that the proposed method is accurate and reproducible with linearity in the range of 100 to 400 ng. The limit of detection and limit of quantification for tenoxicam were 25 and 50 μg/spot, respectively. The proposed method can be employed for the routine analysis of tenoxicam as well as in pharmaceutical formulations.

Hydrogeochemical characterization and geospatial assessment of groundwater quality in the alluvial aquifer of southwestern Punjab in association with health risk assessment due to nitrate and fluoride pollution

Groundwater contamination is a significant threat to human health and hygiene, particularly when high levels of nitrate and fluoride are present. Punjab is currently experiencing a crisis of groundwater depletion and contamination, particularly severe in the southwestern region due to the limited availability of surface water. So, the present study was planned in the Mansa district of Punjab to know the status of groundwater with special reference to nitrate and fluoride and its associated health risks. The study found that all drinking water parameters in the district exceeded the desirable limits. The order of cations found was Na+  > Mg2+  > Ca2+  > K+, and the anions were ordered as HCO3-  > SO42-  > Cl-  > NO3-  > F-. The variation in Na+, K+, Mg2+, and HCO3- levels is attributed to processes such as silicate weathering, evaporation, and direct ion exchange. The dominant types of groundwater in the area are mixed type and Na-Cl type. The concentration of NO3- varied from 13.3 to 56.9 mg L-1 with mean 33.3 mg L-1, while F- ranged from 0.09 to 1.81 mg L-1 with mean 1.07 mg L-1. The study revealed that 23.2% and 12.6% of water samples in the district exceeded the acceptable limits for nitrate and fluoride, respectively. According to the water quality index (WQI), the majority of groundwater in the study area is categorized as very poor (36.6%) for drinking, with the largest contribution from the Budhlada (43.9%) and Sardoolgarh (41.1%) blocks. The hazard quotient (HQ) for NO3- was below 1 for adults. However, HQ was greater than 1 for children in all blocks except for the Bhikhi. Similarly, for fluoride, HQ was less than 1 in all blocks for both children and adults, except for children in Sardoolgarh block. The cancer risk due to nitrate exceeded acceptable limits in all blocks. Conclusively, the study results indicate that the Mansa district of Punjab is facing severe groundwater contamination due to nitrate and fluoride, with the highest contamination levels in Jhunir (47.4% of samples exceeded the acceptable limit of NO3-) and Sardoolgarh (87.18% samples exceeded the desirable limit of F-) blocks of the district. The study recommends implementing strict policies to regulate the use of agrochemicals in fields to mitigate nitrate pollution in groundwater and reduce associated risks.

Exploring the combined effect of heavy metals on accumulation efficiency of Salix alba raised on lead and cadmium contaminated soils

The present study illustrated that Salix alba can accumulate high level of Pb and Cd in different plant parts, with maximum accumulation in roots followed by stem and leaves in the order Cd > Pb > Cd + Pb. The phytoremediation evaluation factors such as bioconcentration factor (BCF) and translocation factor (TF) was higher for Cd over Pb in all plant parts, further the BCF for both Pb and Cd was maximum in root (BCF > 1) followed by stem and leaves. Higher accumulation of Cd over the Pb was observed inside the plant tissues due to Cd mimics with other elements and gets transported through respective transporters. The combined treatment of Pb and Cd affected the bioaccumulation at every treatment level suggesting the negative effect among both elements. Higher survival rate (>85%) was recorded up to 200mgPb/kg and 15mgCd/kg, while further increase in metal concentration reduced the plant efficiency to remediate contaminated soils, hence results in declined survival rate. The FTIR analysis revealed that Pb and Cd accumulation in plants induced changes in carboxy, amino, hydroxyl and phosphate groups that ultimately caused alteration in physiological and biochemical processes of plant and thus provided an insight to the interaction, binding and accumulation of heavy metals.

Microbes mediated alleviation of chromium (Cr VI) stress for improved phytoextraction in fodder maize (Zea mays L.) cultivar

This study investigates the potential of chromium (VI) resistant bacterial isolates to alleviate heavy metal stress in fodder maize plants and enhance phytoremediation. Twenty-one bacterial strains were isolated from contaminated water, with five strains; Bacillus thuringiensis (BHR1), Bacillus cereus (BHR2), Enterobacter cloacae (BHR4), Bacillus pumilus (BHR5), and Bacillus altitudinis (BHR6) selected based on their significant plant-growth promoting (PGP) traits and heavy metal tolerance. Under chromium (Cr VI) stress, the BHR1 strain significantly improved seed germination, seedling length and vigor index of fodder maize variety (J 1007) especially at 150 mg/L Cr (VI), where these parameters increased by 3.75, 3.23 and 6.44 folds, respectively. After 60 days, BHR1 also enhanced shoot and root lengths by 4.91 and 4.06 folds, respectively and increase fresh and dry biomass, especially at higher Cr (VI) concentrations. Photosynthetic pigments, chlorophyll a and b, were also elevated by 3.04 and 2.26 times, respectively. Additionally, BHR1 reduced oxidative stress markers, including proline and malondialdehyde (MDA), and decreased electrolyte leakage, thus improving membrane stability. The strain further increased antioxidant enzyme activities and chromium uptake in root and shoot tissues, enhancing the translocation factor by 95 %. This suggests that BHR1 can significantly promote fodder maize growth and accelerate chromium removal from contaminated soil, offering valuable insights into plant-microbe interactions under Cr (VI) stress.

Antiplasmodial activity of Ajuga bracteosa against Plasmodium berghei infected BALB/c mice

BACKGROUND & OBJECTIVES

The present work was undertaken to evaluate antiplasmodial activity of ethanolic leaves extract of traditional medicinal plant Ajuga bracteosa in Plasmodium berghei infected BALB/c mice along with its phytochemical screening and acute toxicity test to support its traditional use as a remedy for malaria.

METHODS

Plant extract (ethanolic) 250, 500, 750 mg/kg/day was evaluated in the early and established infection along with repository activity in P. berghei infected BALB/c mice through suppressive, curative and preventive test. The phytochemical screening was carried out by employing standard procedures. The acute toxicity was checked through limit test.

RESULTS

The ethanolic leaves extract of A. bracteosa (250, 500 and 750 mg/kg/day) demonstrated a dose-dependent chemosuppression during early and in established infections, along with significant (P<0.05) repository activity. At a concentration of 750 mg/kg/day maximum 77.7 per cent chemosuppression during early infection and 68.8 per cent chemosuppression in repository activity were found. This dose enhanced significant mean survival period up to 27.4 +/- 0.46 days in established infection. ELEAB was found to be safe up to 5 g/kg weight when administrated orally in the female BALB/c mice, which is upper limit for oral administration of the test material to rodents. ED(50) of ELEAB was 300 mg/kg body weight of mice.

INTERPRETATION & CONCLUSION

ELEAB inhibited parasitaemia and enhanced mean survival time in a dose- dependent manner upto 750 mg/kg/day dose in treated mice. Further studies need to be done to isolate and characterize active constituents of extract and to study their mechanism of action.

Reflecting on changes in the drinking and irrigation water quality of rivers Beas, Satluj and confluence waters

Prevention and control of water pollution for maintaining and restoring the wholesomeness of rivers are unavoidable. The current water quality approach of designated best use has some limitations such as it is non-integrative and inflexible with regard to the consideration of variables and does not provide a separate rating scale for a given designated use. We thus used water quality index approach proposed by the Canadian Council of Ministers of the Environment (CCME WQI) to evaluate and develop a separate rating system for drinking and irrigation purposes of rivers Beas, Satluj and their confluence water of the Indian Punjab using information collected over 4 years (2016 to 2019). River Beas exhibited better water quality compared to river Satluj for irrigation as well as for drinking. The overall drinking water quality index (DWQI) for Beas was marginal (45.5), whereas it was poor for Satluj (37.7) and confluence waters (40.1). The spatial variation in DWQI was greater for Satluj compared to Beas and confluence waters reflecting the effect of dumping of untreated industrial and domestic waste waters. Variables such as Total coliform (T. coli), dissolved oxygen (DO), turbidity and biological oxygen demand (BOD) contributed to the deterioration of DWQI. The irrigation water quality index (IWQI) was good for Beas (86), marginal for Satluj (60.1) and fair for confluence waters (71.2). Faecal coliform (F. coli), Kelly ratio (KR) and %Na contributed to the deterioration of IWQI. Calcium-magnesium-bicarbonate (Ca-Mg-HCO3) was the dominant water type in Beas and confluence waters, whereas for Satluj, in addition to Ca-Mg-HCO3, sodium-potassium-chloride-sulphate and mixed water types were also prevalent. The river waters witnessed salinity hazard but did not pose sodicity hazard except at a few locations of Satluj. The study indicates the need to take location specific measures for improving river water quality for drinking as well as irrigation purposes. The current status of water quality calls for an urgent need to formulate stringent policy regulations to maintain the surface water quality.