Composite hydrogels fabricated from konjac glucomannan and gellan gum: Rheological characterization and their potential application in sustainable agriculture

In this study, konjac glucomannan (KG) was incorporated in high acyl gellan (HAG) and low acyl gellan (LAG) hydrogels in different ratios. The addition of KG increased pseudoplasticity and thermal hysteresis values of the hydrogels. Improvement in elasticity and water holding capacity (WHC) was observed in KG-LAG hydrogels. The highest WHC (98.5 %) was observed for 1K1H (KG:HAG = 1:1) and 3K7L (KG:LAG = 3:7) hydrogels. The crystallinity of the composite hydrogels was lower than hydrogels prepared from individual biopolymers. The hydrogels exhibited a rough surface with minute pores in the cross-section, due to the aggregation of glucomannan on the gellan network in the composite hydrogels. While HAG and 1K1H hydrogels exhibited greater swelling at low pH (3.0), LAG and 3K7L exhibited greater swelling at high pH (11.0). At pH 7.0, the hydrogels exhibited swelling indices >300 %. Incorporation of 1K1H hydrogel at 10 % (w/w) in sandy loamy soil under semi-arid conditions increased the germination of fenugreek microgreens from 60 % to 80 % on the 15th day. Furthermore, the moisture evaporation rate of the soil reduced from 35 % to <15 %, positively impacting the physicochemical properties of the microgreens. The composite hydrogels were successful in achieving a controlled release of phosphate fertilizer.

Inclusion of konjac glucomannan in pea protein hydrogels improved the rheological and in vitro release properties of the composite hydrogels

In this study, a composite hydrogel consisting of pea protein and konjac glucomannan (KG) was fabricated using three approaches, namely neutral, salt-set, and alkaline gelation. Hydrogels made from pea protein were brittle and weak. The addition of KG improved the elasticity and water holding capacity of the pea protein hydrogels. Concomitantly, a decrease in syneresis rate and swelling of the composite hydrogels was observed. The alkaline-set hydrogels exhibited the highest resilience to strain. Thixotropicity was found to be less pronounced for salt-set hydrogels. Sulphate had a greater positive effect on the structural recovery and negative effect on hysteresis area than chloride due to the greater salting-out effect of the sulphates. The addition of KG facilitated the formation of an interconnected structure with limited mobility of biopolymer chains. A sharp increase in G' and G" during the temperature ramp indicated the predominance of hydrophobic interactions towards the aggregation of biopolymers. The infrared spectra of the hydrogels revealed a change in secondary structure of proteins on addition of KG. A controlled in vitro release of riboflavin was observed in neutral and salt-set hydrogels. The alkaline-set hydrogels exhibited a prolonged gastric retention time, thereby establishing in vitro antacid activity in the gastric environment.

Rheological performance of film-forming solutions and barrier properties of films fabricated from cold plasma-treated high methoxyl apple pectin and crosslinked by Ca2+: Impact of plasma treatment voltage

Sustainable and "green" technologies, such as cold plasma are gaining attention in recent times for improving the functional properties of hydrocolloids. Chemical modifications of hydrocolloids require several chemicals and solvents, which are not environment-friendly. The major objective of the study was to understand the impact of plasma treatment (170-230 V|15 min) on the rheology of film-forming solutions (FFS) and the barrier properties of pectin films. The film-forming properties of plasma-treated pectin were investigated in the presence of two plasticizers, namely, glycerol and polyethylene glycol (PEG) 400. The effects of cross-linking by CaCl₂ on the rheology of FFS and barrier properties of the films were discussed. A voltage-dependent decrease in the apparent viscosity of FFS was observed. The viscoelastic properties of the FFS were enhanced due to cross-linking. Glycerol exhibited a better plasticizing effect than PEG. Cross-linking and increasing voltage synergistically contributed towards lower oxygen and carbon dioxide transmission rates. The moisture sorption rate and capacity of the films increased with the voltage of the treatment. The resistance to extension of the films made from glycerol and PEG decreased with voltage, with no significant change in extensibility. On the other hand, the cross-linking by Ca²⁺ and plasma treatment enhanced the resistance to extension for the films made from both the plasticizers. While the increasing hydrophilicity and opacity of the films were a major drawback of plasma modification, the increase in UV barrier property of the films was an advantage of the modification.

Pasteurization of fruit juices by pulsed light treatment: A review on the microbial safety, enzymatic stability, and kinetic approach to process design

Pulsed light (PL) is a polychromatic radiation-based technology, among many other non-thermal processing techniques. The microbiological lethality of the PL technique has been explored in different food matrices along with their associated mechanisms. Pasteurization of fruit juice requires a 5-log cycle reduction in the resistant pathogen in the product. The manufacturers look toward achieving the microbial safety and stability of the juice, while consumers demand high-quality juice. Enzymatic spoilage in fruit juice is also a crucial factor that needs attention. The retailers want the processed juice to be stable, which can be achieved by inactivating the spoilage enzymes and native microflora inside it. The present review argued about the potential of PL technology to produce a microbiologically safe and enzymatically stable fruit juice with a minimal loss in bioactive compounds in the product. Concise information of factors affecting the PL treatment (PLT), primary inactivation mechanism associated with microorganisms, enzymes, the effect of PLT on various quality attributes (microorganisms, spoilage enzymes, bioactive components, sensory properties, color), and shelf life of fruit juices has been put forward. The potential of PL integrated with other non-thermal and mild thermal technologies on the microbial safety and stability of fruit juices has been corroborated. The review also provides suggestions to the readers for designing, modeling, and optimizing the PLT and discusses the use of various primary, secondary kinetic models in detail that have been utilized for different quality parameters in juices. Finally, the challenges and future need associated with PL technology has been summarized.

Multifunctional Thio-Stabilized Gold Nanoparticles for Near-Infrared Fluorescence Detection and Imaging of Activated Caspase-3

Background

Gold nanoparticles (AuNPs) are commonly used in nanomedicine because of their unique spectral properties, chemical and biological stability, and ability to quench the fluorescence of organic dyes attached to their surfaces. However, the utility of spherical AuNPs for activatable fluorescence sensing of molecular processes have been confined to resonance-matched fluorophores in the 500 nm to 600 nm spectral range to maximize dye fluorescence quenching efficiency. Expanding the repertoire of fluorophore systems into the NIR fluorescence regimen with emission >800 nm will facilitate the analysis of multiple biological events with high detection sensitivity.

Objective

The primary goal of this study is to determine if spherical AuNP-induced radiative rate suppression of non-resonant near-infrared (NIR) fluorescent probes can serve as a versatile nanoconstruct for highly sensitive detection and imaging of activated caspase-3 in aqueous media and cancer cells. This required the development of activatable NIR fluorescence sensors of caspase-3 designed to overcome the nonspecific degradation and release of the surface coatings in aqueous media.

Method

We harnessed the fluorescence-quenching properties and multivalency of spherical AuNPs to develop AuNP-templated activatable NIR fluorescent probes to detect activated caspase-3, an intracellular reporter of early cell death. Freshly AuNPs were coated with a multifunctional NIR fluorescent dye-labeled peptide (LS422) consisting of an RGD peptide sequence that targets α_vβ₃-integrin protein (α_vβ₃) on the surface of cancer cells to mediate the uptake and internalization of the sensors in tumor cells; a DEVD peptide sequence for reporting the induction of cell death through caspase-3 mediated NIR fluorescence enhancement; and a multidentate hexacysteine sequence for enhancing self-assembly and stabilizing the multifunctional construct on AuNPs. The integrin binding affinity of LS422 and caspase-3 kinetics were determined by a radioligand competitive binding and fluorogenic peptide assays, respectively. Detection of intracellular caspase-3, cell viability, and the internalization of LS422 in cancer cells were determined by confocal NIR fluorescence spectroscopy and microscopy.

Results

Narrow size AuNPs (13 nm) were prepared and characterized by transmission electron microscopy and dynamic light scattering. When assembled on the AuNPs, the binding constant of LS422 for α_vβ₃ improved 11-fold from 13.2 nM to 1.2 nM. Whereas the catalytic turnover of caspase-3 by LS422-AuNPs was similar to the reference fluorogenic peptide, the binding affinity for the enzyme increased by a factor of 2. Unlike the α_vβ₃ positive, but caspase-3 negative breast cancer MCF-7 cells, treatment of the α_vβ₃ and caspase-3 positive lung cancer A549 cells with Paclitaxel showed significant fluorescence enhancement within 30 minutes, which correlated with caspase-3 specific activation of LS422-AuNPs fluorescence. Incorporation of a 3.5 mW NIR laser source into our spectrofluorometer increased the detection sensitivity by an order of magnitude (limit of detection ~0.1 nM of cypate) and significantly decreased the signal noise relative to a xenon lamp. This gain in sensitivity enabled the detection of substrate hydrolysis at a broad range of inhibitor concentrations without photobleaching the cypate dye.

Conclusion

The multifunctional AuNPs demonstrate the use of a non-resonant quenching strategy to design activatable NIR fluorescence molecular probes. The nanoconstruct offers a selective reporting method for detecting activated caspase-3, imaging of cell viability, identifying dying cells, and visualizing the functional status of intracellular enzymes. Performing these tasks with NIR fluorescent probes creates an opportunity to translate the in vitro and cellular analysis of enzymes into in vivo interrogation of their functional status using deep tissue penetrating NIR fluorescence analytical methods.

Immunity boosting nutraceuticals: Current trends and challenges

The immune function of the human body is highly influenced by the dietary intake of certain nutrients and bioactive compounds present in foods. The preventive effects of these bioactive ingredients against various diseases have been well investigated. Functional foods are consumed across various diverse cultures, in some form or the other, which provide benefits greater than the basic nutritional needs. Novel functional foods are being developed using novel bioactive ingredients such as probiotics, polyunsaturated fatty acids, and various phytoconstituents, which have a range of immunomodulatory properties. Apart from immunomodulation, these ingredients also affect immunity by their antioxidant, antibacterial, and antiviral properties. The global pandemic of Severe Acute Respiratory Syndrome Coronavirus-2 has forced the scientific community to race against time to find a proper and effective drug or a vaccine. In this review, various non-pharmacological interventions using nutraceuticals and functional foods have been discussed. PRACTICAL APPLICATIONS: Despite a plethora of research being undertaken to understand the immunity boosting properties of the various bioactive present in food, the findings are not translating to nutraceutical products in the market. Immunity has proved to be one of the most important factors for the health and well-being of an individual, especially when the world has been under the grip of the novel coronavirus Severe Acute Respiratory Syndrome Coronavirus-2. The anti-inflammatory properties of various nutraceuticals can come out as potential inhibitors of the various inflammatory processes such as cytokine storms, usually being observed in COVID 19. This review gives an insight into how various nutraceuticals can help in the prevention of various diseases through different mechanisms. The lack of awareness and proper clinical trials pose a challenge to the nutraceutical industry. This review will help and encourage researchers to further design and develop various functional foods, which might help in building immunity.

Period multiplication cascade at the order-by-disorder transition in uniaxial random field XY magnets

Uniaxial random field disorder induces a spontaneous transverse magnetization in the XY model. Adding a rotating driving field, we find a critical point attached to the number of driving cycles needed to complete a limit cycle, the first discovery of this phenomenon in a magnetic system. Near the critical drive, time crystal behavior emerges, in which the period of the limit cycles becomes an integer n > 1 multiple of the driving period. The period n can be engineered via specific disorder patterns. Because n generically increases with system size, the resulting period multiplication cascade is reminiscent of that occurring in amorphous solids subject to oscillatory shear near the onset of plastic deformation, and of the period bifurcation cascade near the onset of chaos in nonlinear systems, suggesting it is part of a larger class of phenomena in transitions of dynamical systems. Applications include magnets, electron nematics, and quantum gases.

Antibacterial Activities of Clove (Syzygium aromaticum) Extracts Against Three Food Borne Pathogens: Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa

Evaluation of the in vitro antibacterial activity of aqueous and ethanolic extracts isolated from Clove (Syzygium aromaticum) buds against three food borne pathogens, gram-positive Staphylococcus aureus and gram-negative Escherichia coli & Pseudomonas aeruginosa. This interventional study was carried out during the period of July 2018 to June 2019 in the Department of Pharmacology and Therapeutics with the collaboration of Department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh. The antibacterial activity was tested at different concentrations of both extracts of spice by using disc diffusion & broth dilution method. The extracts were prepared by using solvents aqueous & ethanol. The test microorganisms were also tested for their activity against a standard antibiotic Gentamicin (80mg) by broth dilution method and the result was compared with that of Aqueous and Ethanolic extracts. Aqueous and ethanolic extracts of clove had inhibitory activity against the test bacteria. Among different concentrations of the ACE, 500μg/ml & above concentration showed inhibitory effect against Staphylococcus aureus & Escherichia coli and 700μg/ml & above concentration showed inhibitory effect against Pseudomonas aeruginosa. In case of ECE, 500μg/ml & above concentration showed inhibitory effect against aforesaid bacteria. In disc diffusion method, S. aureus was found to be most susceptible to ACE (30.5mm) & Pseudomonas aeruginosa was found to be most susceptible to ECE (38mm). Minimum inhibitory concentrations (MIC) of ECE were lower than ACE for the test bacteria except Staphylococcus aureus where MICs of ACE & ECE were the same. This result was also compared against a standard antibiotic Gentamicin where the MICs of Gentamicin were lower in comparison to MICs of ACE & ECE. The present study showed that aqueous and ethanolic extracts of Clove demonstrated antibacterial effects against food borne pathogens.

Epidermal growth factor receptor T790M testing in progressed lung cancer: A review of sensitive methods for analysis of tissue and liquid biopsy samples

Lung cancer is one of the major causes of mortality worldwide and is on the rise in India. The identification of epidermal growth factor receptor (EGFR) mutations in nonsmall cell lung cancer (NSCLC) has paved the way for personalized therapy in lung cancer with EGFR-tyrosine kinase inhibitors (TKIs). Despite the proven efficacy of EGFR-TKIs in patients harboring EGFR mutations, their clinical utility is limited by the development of acquired resistance mechanisms by the tumor cells. T790M mutation accounts for 60% of all resistance mechanisms to EGFR TKIs and is responsible for treatment failure with first- and second-generation TKIs. With the development of novel therapeutic agents such as osimertinib to overcome this resistance mechanism, it is essential to detect patients harboring T790M mutation. There are several limitations with the use of tissue biopsy specimens for molecular testing such as poor quality and quantity of sample, tumor heterogeneity, occurrence of complications, and issues with repeat biopsy. Liquid biopsy offers a noninvasive approach that can be used for diagnostic purposes as well as for monitoring treatment response and evaluation of resistance mechanisms. This review focuses on the methods for molecular testing of tissue and liquid biopsy specimens for EGFR mutations, particularly EGFR T790M mutation.

Flame resistant cellulosic substrate using banana pseudostem sap

Flame retardancy was imparted in cellulosic cotton textile using banana pseudostem sap (BPS), an eco-friendly natural product. The extracted sap was made alkaline and applied in pre-mordanted bleached and mercerized cotton fabrics. Flame retardant properties of both the control and the treated fabrics were analysed in terms of limiting oxygen index (LOI), horizontal and vertical flammability. Fabrics treated with the non-diluted BPS were found to have good flame retardant property with LOI of 30 compared to the control fabric with LOI of 18, i.e., an increase of 1.6 times. In the vertical flammability test, the BPS treated fabric showed flame for a few seconds and then, got extinguished. In the horizontal flammability test, the treated fabric showed no flame, but was burning only with an afterglow with a propagation rate of 7.5 mm/min, which was almost 10 times lower than that noted with the control fabric. The thermal degradation and the pyrolysis of the fabric samples were studied using a thermogravimetric analysis (TGA), and the chemical composition by FTIR, SEM and EDX, besides the pure BPS being characterized by EDX and mass spectroscopy. The fabric after the treatment was found to produce stable natural khaki colour, and there was no significant degradation in mechanical strengths. Based on the results, the mechanism of imparting flame retardancy to cellulosic textile and the formation of natural colour on it using the proposed BPS treatment have been postulated.

Malignant Leiomyoblastoma: An Incidental Diagnosis

DOI: http://www.dx.doi.org/10.3126/njog.v7i2.11147   Nepal Journal of Obstetrics and Gynaecology / Vol 7 / No. 2 / Issue 14 / July-Dec, 2012 / 55-56

First report of detection and molecular confirmation of Plasmodium ovale from severe malaria cases in central India

OBJECTIVE

We report for the first-time detection of Plasmodium ovale in central India.

METHODS

From 2010, all hospitalised suspected malaria cases at the malaria clinic of the Regional Medical Research Centre for Tribals in Bastar district, central India, were screened. Plasmodium species were identified by microscopy and species-specific nested PCR of 18s rRNA.

RESULTS

Of 256 enrolled cases of confirmed P. falciparum malaria by microscopy, P. ovale infection was detected in three cases (1.2%) by PCR and sequencing. Of these three cases, one had cerebral malaria and another had severe malaria anaemia. In both of these cases, P. ovale infection was mixed with P. falciparum, while in third case the infection was mixed with both P. falciparum and P. vivax. Phylogenetic analysis revealed that these isolates showed closed homology with West African genotypes.

CONCLUSION

All three hospitalised patients were originally residents of remote inaccessible forest villages and never moved out of their residence. This finding also has implications in malaria control and elimination as P. ovale causes relapses. This study highlights the need of molecular diagnosis of malaria species for appropriate treatment and control.

Docosahexaenoic acid stimulates tube formation in first trimester trophoblast cells, HTR8/SVneo

Angiogenesis is a key factor in the placentation process and vascular remodeling that involves several growth factors such as vascular endothelial growth factor (VEGF) and angiopoietin-like protein 4 (ANGPTL4). PPARs are involved in the placentation process but not much information is available on whether their ligands such as fatty acids have any effects on these processes. We therefore investigated the effect of fatty acids (arachidonic acid, 20:4 n-6(ARA), eicosapentaenoic acid, 20:5 n-3(EPA), docosahexaenoic acid, 22:6 n-3 (DHA) and oleic acid, 18:1 n-9 (OA)) on tube formation (as a measure of angiogenesis) on matrigel in the first trimester trophoblast cells, HTR8/SVneo. In addition we also investigated the effects of fatty acids on expression of genes involved in angiogenesis (VEGF and ANGPTL4) and lipid metabolism in these cells. Gene expression was determined after incubating these cells with different fatty acids for 24 h using real-time qRT-PCR, whereas VEGF and ANGPTL4 proteins were measured by respective ELISA kits. Of all the fatty acids tested, DHA increased tube formation to the greatest extent. DHA-induced increase in tube length was 583%, 247% and 70% over control, OA and EPA, respectively (p < 0.05). In addition, DHA stimulated cell proliferation by 150% of these cells. Of all fatty acids investigated, only DHA stimulated VEGF mRNA expression and protein secretion compared with control. Unlike DHA, other fatty acids (OA, EPA, ARA) stimulated ANGPTL4 mRNA expression and protein secretion in these cells. An inhibitor of VEGF decreased DHA stimulated tube formation in these cells. Altogether these data indicate that DHA may potently influence the placentation process by stimulating tube formation and this effect may be mediated in part via VEGF in first trimester trophoblast cells.

Direct observation of broken time-reversal symmetry on the surface of a magnetically doped topological insulator

We study interference patterns of a magnetically doped topological insulator Bi(2-x)Fe(x)Te(3+d) by using Fourier transform scanning tunneling spectroscopy and observe several new scattering channels. A comparison with angle-resolved photoemission spectroscopy allows us to unambiguously ascertain the momentum-space origin of distinct dispersing channels along high-symmetry directions and identify those originating from time-reversal symmetry breaking. Our analysis also reveals that the surface state survives far above the energy where angle-resolved photoemission spectroscopy finds the onset of continuum bulk bands.

Randomised controlled trial evaluating the role of tirofiban in high-risk non-ST elevation acute coronary syndromes: an East Indian perspective

INTRODUCTION

Glycoprotein IIb/IIIa inhibitors such as tirofiban inhibit platelet aggregation. We evaluated the immediate and early outcomes in patients with high-risk non-ST elevation acute coronary syndrome (NSTE ACS) who received tirofiban with conventional therapy compared to patients who received only conventional therapy (a combination of aspirin, clopidogrel, low-molecular-weight heparin with or without beta-blockers and angiotensin-converting enzyme inhibitors).

METHODS

A total of 165 patients received conventional therapy with a placebo, and 136 patients received conventional therapy with tirofiban after randomisation. The outcomes were measured on Day 7, Day 14, one month and three months after the administration of therapy.

RESULTS

A significant reduction was noted in the occurrence of primary endpoints in patients receiving tirofiban, compared to those who received a placebo at seven days (14 versus 32; p-value is 0.036), 14 days (14 versus 28; p-value is 0.043), one month (19 versus 34; p-value is 0.01) and three months (30 versus 44; p-value is less than 0.001) after administration. There was a significant reduction in the occurrence of fatal myocardial infarction (MI) (1 versus 8; p-value is 0.044) and non-fatal MI at Day 7 (1 versus 8; p-value is 0.044), and refractory ischaemia at the end of one month (14 versus 24; p-value is 0.04) and three months (25 versus 36; p-value is less than 0.01) in patients receiving tirofiban as compared to those receiving a placebo.

CONCLUSION

It may be concluded that tirofiban has a definite role in improving the outcome of patients with high-risk NSTE ACS.

Adenomyosis: still largely under-diagnosed

Underlying adenomyosis is often the cause of treatment failure for patients undergoing Mirena insertion, endometrial ablation and/or hysteroscopic resection for abnormal uterine bleeding and/or pelvic pain. In this cohort of abnormal uterine bleeding, clinicians rarely considered adenomyosis as a differential diagnosis. In such cases, gynaecologists concentrated primarily on menstrual flow. Symptoms of pelvic pain, dyspareunia, pelvic pressure symptoms and type of dysmenorrhoea were not queried. Frequently, no correlation was sought to account for a uterus noted to be enlarged either clinically or at hysteroscopy. Given the limitation of ultrasound scan (USS) in diagnosing adenomyosis, and gynaecologists' reliance on USS findings, adenomyosis often remains undiagnosed before a hysterectomy. An earlier diagnosis of adenomyosis requires a good history, correlation of clinical examination and ultrasound scan findings and a back-up MRI service. Once adenomyosis is suspected, women can be appropriately counselled so that they are fully aware of the possible failure of conservative management. If conservative management is chosen, they should be followed-up and hysterectomy offered for persistent symptoms.

A diagnostic dilemma: functioning noncommunicating uterine horn and elevated levels of CA125

BACKGROUND

Müllerian duct abnormalities are important to diagnose, considering the various clinical manifestations, implications for reproductive life, different treatment options, and prognoses. However, they are often difficult to diagnose, especially by noninvasive means. Here we discuss the diagnostic difficulty incurred in a case of unicornuate uterus with functioning noncommunicating horn having a high level of cancer antigen 125 as a presenting feature.

CASE

Unicornuate uterus with raised serum CA125.

CONCLUSIONS

Mullerian duct anomaly can be a differential diagnosis in women with adnexal mass and elevated CA125.