AI-Assisted Automated Identification of Human Activities Using Ficus religiosa Leaf-Based Triboelectric Nanogenerator.

Movement monitoring and effective identification of different actions are the keys that help in fitness services, health status, clinical studies, etc. In this technological era, Internet of Things (IoT) technologies, including smart wireless devices and sensors, are very effectively used for monitoring human activities, but the demand for sustainable and green power sources is a crucial issue with these devices. Triboelectric nanogenerators (TENG) are proven to be promising applications in these devices because they harvest energy from the surrounding environment and eliminate the use of batteries as power sources. As a green energy source, this study emphasizes the fabrication of biodegradable materials-based TENGs, which are eco-friendly and are related to clean and green energy as per the UN's sustainable development goals SDG 7 (affordable and clean energy). In the present work, a natural Ficus religiosa leaf (FRL) of the F. religiosa tree is used in designing and fabricating a TENG (FRL-TENG). Also, an approach is discussed to compare the performance of FRL-TENG with TENGs fabricated from other waste biodegradable materials such as garlic tunic, onion tunic, and eggshell membrane (ESM). During the experimental study, it is observed that the FRL-based TENG produced maximum voltage in comparison to other material combinations selected in this study. The generated electric output from these TENG combinations is also used to power an array of tens of green-light-emitting diodes (LEDs). Furthermore, this paper also proposes the use of FRL-TENG as a wearable sensor to collect information and monitor the physical activities of the user, viz., walk, jump, and run. To recognize the movement status, the FRL-TENG sensor is integrated with an extra randomized tree-based machine learning model for accurately distinguishing the user's three activities with an accuracy of 96%. The work showcases an innovative approach to encourage customized uses of TENG sensors in human motion monitoring and permits the development of intelligent, self-powered systems for new applications.

Small Molecule as Fluorescent Probes for Monitoring Intracellular Enzymatic Transformations.

All cellular processes are the results of synchronized actions of several intracellular biochemical pathways. Recent emphasis is to visualize such pathways using appropriate small molecular reagents, dye-labeled proteins, and genetically encoded fluorescent biosensors that produce a luminescence ON response either on selective binding or on reacting with an analyte that is produced through a specific biochemical/enzymatic transformation. Studying such enzymatic processes by probing the fluorescence response as the read-out signal is expected to provide important insights into crucial biochemical transformations induced by an enzyme in its native form. Many of such studies are extended for monitoring enzymatic transformations under in vitro or in vivo condition. A few of the recent reports reveal that such molecular probes are even capable of quantifying abnormal levels of enzymes in real-time and is linked to the key area of clinical diagnostics and chemical biology. A synchronized analysis of all such reports helps in developing a rationale for designing purpose-built molecular probes or chemodosimeters as well as newer reagents for studying crucial enzymatic process or quantification of the respective enzyme. In this review, an attempt will be there to highlight several recent bioimaging reagents and studies that have provided insights into crucial biochemical or enzymatic transformations.

Mitochondria Targeting Non-Isocyanate-Based Polyurethane Nanocapsules for Enzyme-Triggered Drug Release.

Surface engineering of nanocarriers allows fine-tuning of their interactions with biological organisms, potentially forming the basis of devices for the monitoring of intracellular events or for intracellular drug delivery. In this context, biodegradable nanocarriers or nanocapsules capable of carrying bioactive molecules or drugs into the mitochondrial matrix could offer new capabilities in treating mitochondrial diseases. Nanocapsules with a polymeric backbone that undergoes programmed rupture in response to a specific chemical or enzymatic stimulus with subsequent release of the bioactive molecule or drug at mitochondria would be particularly attractive for this function. With this goal in mind, we have developed biologically benign nanocapsules using polyurethane-based, polymeric backbone that incorporates repetitive ester functionalities. The resulting nanocapsules are found to be highly stable and monodispersed in size. Importantly, a new non-isocyanate route is adapted for the synthesis of these non-isocyanate polyurethane nanocapsules (NIPU). The embedded ester linkages of these capsules' shells have facilitated complete degradation of the polymeric backbone in response to a stimulus provided by an esterase enzyme. Hydrophilic payloads like rhodamine or doxorubicin can be loaded inside these nanocarriers during their synthesis by an interfacial polymerization reaction. The postgrafting of the nanocapsules with phosphonium ion, a mitochondria-targeting receptor functionality, has helped us achieve the site-specific release of the drug. Co-localization experiments with commercial mitotracker green as well as mitotracker deep red confirmed localization of the cargo in mitochondria. Our in vitro studies confirm that specific release of doxorubicin within mitochondria causes higher cytotoxicity and cell death compared to free doxorubicin. Endogenous enzyme triggered nanocapsule rupture and release of the encapsulated dye is also demonstrated in a zebrafish model. The results of this proof-of-concept study illustrate that NIPU nanocarriers can provide a site-specific delivery vehicle and improve the therapeutic efficacy of a drug or be used to produce organelle-specific imaging studies.

Steric Crowding of the Turn Region Alters the Tertiary Fold of Amyloid-ß18-35 and Makes It Soluble.

Aß self-assembles into parallel cross-ß fibrillar aggregates, which is associated with Alzheimer's disease pathology. A central hairpin turn around residues 23-29 is a defining characteristic of Aß in its aggregated state. Major biophysical properties of Aß, including this turn, remain unaltered in the central fragment Aß18-35. Here, we synthesize a single deletion mutant, ΔG25, with the aim of sterically hindering the hairpin turn in Aß18-35. We find that the solubility of the peptide goes up by more than 20-fold. Although some oligomeric structures do form, solution state NMR spectroscopy shows that they have mostly random coil conformations. Fibrils ultimately form at a much higher concentration but have widths approximately twice that of Aß18-35, suggesting an opening of the hairpin bend. Surprisingly, two-dimensional solid state NMR shows that the contact between Phe(19) and Leu(34) residues, observed in full-length Aß and Aß18-35, is still intact in these fibrils. This is possible if the monomers in the fibril are arranged in an antiparallel ß-sheet conformation. Indeed, IR measurements, supported by tyrosine cross-linking experiments, provide a characteristic signature of the antiparallel ß-sheet. We conclude that the self-assembly of Aß is critically dependent on the hairpin turn and on the contact between the Phe(19) and Leu(34) regions, making them potentially sensitive targets for Alzheimer's therapeutics. Our results show the importance of specific conformations in an aggregation process thought to be primarily driven by nonspecific hydrophobic interactions.

Repurposing of Various Current Medicines as Radioprotective Agents.

BACKGROUND: The side effects of ionising radiation include skin changes, dry mouth, hair loss, low blood count, and the mutagenic effect on normal cells when utilized in radiotherapy for cancer treatment. These radiations can cause damage to the cell membrane, lipids, proteins, and DNA and generate free radicals. Evidence reports stated that radiotherapy accounts for 17-19% of secondary malignancies, labelling this treatment option a double-edged sword. OBJECTIVE: Radioprotective molecules are used for mitigating radiotherapy's side effects. These agents show free radical scavenging, antioxidant, collagen synthesis inhibition, protease inhibition, immune stimulation, increased cytokine production, electron transfer, and toxicity reduction properties. The most frequently used amifostine has an array of cancer applications, showing multitarget action as nephroprotective to cisplatin and reducing the chances of xerostomia. Many other agents, such as metformin, edaravone, mercaptopropionylglycine, in specific diseases, such as diabetes, cerebral infarction, cystinuria, have shown radioprotective action. This article will discuss potentially repurposed radioprotectors that can be used in the clinical setting, along with a brief discussion on specific synthetic agents like amifostine and PrC-210. METHODS: Rigorous literature search using various electronic databases, such as PubMed, ScienceDirect, Scopus, EMBASE, Bentham Science, Cochrane Library, etc., was made. Peer-review research and review papers were selected, studied, reviewed, and analysed. CONCLUSION: Safety and risk-free treatment can be guaranteed with the repurposed agents. Agents like metformin, captopril, nifedipine, simvastatin, and various others have shown potent radioprotective action in various studies. This review compiled repurposed synthetic radioprotective agents.

Radioprotectors: Nature's Boon.

BACKGROUND: Major approach in controlling as well as eradicating the cancerous growth is through radiotherapy, but this treatment leads to toxicity in the normal cells, leading to secondary malignancies, teratogenesis, and necrosis. More than 15,000 malignancies occur due to exposure to harmful radiations during computed tomography scans. Natural products are non-toxic; there have been reports that herbal products, when given along with radiation, have shown increased tumor control property. The discussed agents in this review have potential antioxidant, immunomodulatory, free radical scavenging, metal chelating, and anti-inflammatory properties. OBJECTIVE: To reduce the chances of toxicity, reduction in radiation dose or reducing the frequency of the therapy is made which usually leads to a therapeutically poor outcome. The most feasible method is to protect the normal cells by administration of radioprotective agents either before or after the exposure. These agents have been tested on animals and human cell models for evaluating their safety window and toxicity profile at the cellular level. The study aims to compile the effective natural radioprotective agents available, which can be further exploited by using certain QSAR studies to increase their potency. METHOD: Structured literature search from EMBASE, PubMed, Bentham Science, Scopus, and ScienceDirect was carried out and appropriate peer-reviewed review articles, as well as certain research articles, were included and compiled in this review paper. CONCLUSION: As various studies have indicated the harmful effects of ionizing radiations on normal cells, to reduce these effects, radioprotective agents are used before or after exposure to radiations. Compounds derived from natural sources are proved to have few side effects and they possess radioprotective property due to the presence of alkaloids, resins, volatile oils, tannins in their molecular structure. Various plants having such radioprotective constitutes have been identified for their radioprotective action and compiled in the present study.

Large Area Self-Assembled Ultrathin Polyimine Nanofilms Formed at the Liquid-Liquid Interface Used for Molecular Separation.

Separation membranes with higher molecular weight cut-offs are needed to separate ions and small molecules from a mixed feed. The molecular sieving phenomenon can be utilized to separate smaller species with well-defined dimensions from a mixture. Here, the formation of freestanding polyimine nanofilms with thicknesses down to ≈14 nm synthesized via self-assembly of pre-synthesized imine oligomers is reported. Nanofilms are fabricated at the water-xylene interface followed by reversible condensation of polymerization according to the Pieranski theory. Polyimine nanofilm composite membranes are made via transferring the freestanding nanofilm onto ultrafiltration supports. High water permeance of 49.5 L m-2 h-1 bar-1 is achieved with a complete rejection of brilliant blue-R (BBR; molecular weight = 825 g mol-1 ) and no more than 10% rejection of monovalent and divalent salts. However, for a mixed feed of BBR dye and monovalent salt, the salt rejection is increased to ≈18%. Membranes are also capable of separating small dyes (e.g., methyl orange; MO; molecular weight = 327 g mol-1 ) from a mixed feed of BBR and MO. Considering a thickness of ≈14 nm and its separation efficiency, the present membrane has significance in separation processes.

Mitochondriotropic lanthanide nanorods: implications for multimodal imaging.

Two-photon active mitochondriotropic lanthanide nanorods for high resolution fluorescence imaging. The presence of Gd in the nanorods also enabled us to utilize this material as a T1-T2 dual-mode contrast reagent for recording magnetic resonance images of the mouse brain.

Stimuli-Responsive Nanocapsules for the Spatiotemporal Release of Melatonin: Protection against Gastric Inflammation.

Melatonin is a secretory product of the pineal gland that regulates circadian rhythm. It is also well-known for its anti-inflammatory and antioxidant properties against the damaging influences of reactive oxygen species. To improve its therapeutic efficacy, a new formulation with melatonin loaded in a stimuli-responsive polymeric nanocapsule has been prepared following an inverse mini-emulsion technique. The colloidal stability of the melatonin-loaded nanocapsules (MNCs) is studied using dynamic light scattering, while the morphology of these MNCs is characterized using various electron microscopies. These MNCs have an inner diameter of 80-120 nm with a cell wall thickness of 29 ± 11 nm. The emission band maximum for melatonin appears at 350 nm following excitation at 305 nm (quantum yield, Φ350 = 0.13). The self-quenching nature of the entrapped melatonin molecules inside the nanocapsules attributes to a lower Φ350 value for the MNCs. The controlled release of melatonin from MNCs in an in vitro condition is achieved by inducing a rupture of the polymeric backbone through maintaining a certain media pH (∼2.0-4.0) as an external stimulus, and this accounts for a significant enhancement in its characteristic luminescence. The H,K-ATPase, an integral membrane protein, maintains this specific pH range in the interior of the gastrointestinal tract. This methodology is adopted for developing an efficient drug delivery process in the gastric environment. A significant improvement in the AGS cell survival under oxidative stress conditions is observed during preincubation with MNCs compared to free melatonin. In a murine model of the stress-induced gastric ulcer, MNCs outperformed free melatonin in terms of drug efficacy. The value for the gastric ulcer index is reduced from ∼30 to ∼15 by free melatonin and from ∼30 to ∼8 by MNCs treatments, respectively. Such formulation could be a step forward for developing more efficient melatonin-based gastroprotective supplements.

Two-dimensional lanthanide coordination polymer nanosheets for detection of FOX-7.

Despite the recent surge of interest in two-dimensional (2D) inorganic nanosheets derived from photoactive coordination polymers of lanthanide ions having interesting optical properties, research in this area is still in its infancy. Luminescent lanthanide ions, Eu(iii) or/and Tb(iii), as well as a bis-terpyridine ligand (L), were used in this study as the building blocks for the synthesis of the archetypical layered structure of coordination polymers (CPs) (L·Eu/L·Tb). 2D-nanosheets were obtained through exfoliation of the layered precursor of CPs in a suitable solvent system following a sonication-assisted strategy. These nanosheets exhibit lateral sizes on the micrometer scale (0.3-1 µm) and an ultrathin thickness of 2-6.5 nm. 1,1-Diamino-2,2-dinitroethene or FOX-7 is an insensitive high explosive; in a binder mixture, it exhibits a slightly superior detonation velocity of 8870 m s-1 in comparison to RDX. The insensitive nature of FOX-7 makes it a key component for the development of low vulnerable high explosive compositions for further application in weaponry. The growing demand for FOX-7, for use as a suitable replacement of conventional explosives, is of serious concern to human security. Achieving rapid and efficient detection of this unexplored explosive is a challenging task. In the present study, the developed luminescent nanosheets were used for the first time for micromolar level detection of FOX-7 both in solution and in the solid state. A visually distinct color change of the nanosheets from red (L·Eu) and green (L·Tb) to colorless was witnessed upon UV light irradiation during the detection process. Notably, the solid-state detection technique could be exploited for developing a commercial spray kit for quick onsite screening of this important explosive.

Two photon excitable graphene quantum dots for structured illumination microscopy and imaging applications: lysosome specificity and tissue-dependent imaging.

Biocompatible graphene quantum dots (GQDs), obtained from extracts of neem root, are found to be suitable for structured illumination microscopy and two-photon microscopy (TPM). Results of TPM and confocal luminescence microscopy ensure lysosome specificity in live cells and tissue-dependent localization in zebrafish, respectively, of GQDs.

Imaging cellular trafficking processes in real time using lysosome targeted up-conversion nanoparticles.

ß-NaYF4:Yb,Gd up-conversion nanoparticles, UCNPs, surface functionalized with suitable targetting peptides function as nontoxic lysosome-specific imaging probes.

Ameliorative potential of vitamin P and digoxin in ischemic-reperfusion induced renal injury using the Langendorff apparatus.

AIMS: The present study has been designed to investigate the ameliorative potential of vitamin P, and digoxin in ischemic-reperfusion (I/R)-induced renal injury in isolated rat kidney preparations by using the Langendorff apparatus. MAIN METHODS: Vitamin P (50 and 100 mg/kg; p.o.) was administered to rats for 5 consecutive days. On the 6th day, isolated kidneys were subjected to 30 min of ischemia followed by 120 min of reperfusion by constant flow (8 ml/min). The total renal effluent was collected at various time intervals (i.e., basal, 0, 15, 30, 45 and 60 min). In addition, urea, creatinine, and creatine kinase (CK) activity were evaluated in the renal effluent, and TBARS, GSH, and Na(+)-K(+)-ATPase activity were evaluated in tissue. KEY FINDINGS: I/R of renal tissue produced a rise in the activity of CK and the levels of urea and creatinine in the renal effluent, as well as in the activity of Na(+)-K(+)-ATPase and levels of TBARS in the tissue. Additionally, it decreased GSH levels when compared with the sham control group. Digoxin served as positive control in the present work. Treatment with vitamin P (100 mg/kg), and digoxin (500 µg/kg) produced a significant (P<0.05) ameliorative effect against the I/R induced changes in biomarkers. SIGNIFICANCE: The renoprotective effect of vitamin P is caused by its inhibition of Na(+)-K(+)-ATPase activity, which subsequently results in free radical scavenging and anti-infarct properties. Therefore, this vitamin can be useful in the management of renovascular disorders.

Investigation of therapeutic potential and molecular mechanism of vitamin P and digoxin in I/R-induced myocardial infarction in rat.

Ischemic-reperfusion (I/R) is a major event in the pathogenesis of ischemic heart disease that leads to higher rate of mortality. The study has been designed to investigate the therapeutic potential and molecular mechanism of vitamin P and digoxin in I/R-induced myocardial infarction in isolated rat heart preparation by using Langendorff apparatus. The animals were treated with vitamin P (50 and 100 mg/kg; p.o.) and digoxin (500 µg/kg) for 5 consecutive days. Digoxin served as a positive control in the present study. On the sixth day, the heart was harvested and induced to 30 min of global ischemia followed by 120 min of reperfusion using Langendorff apparatus. The coronary effluent was collected at different time intervals (i.e. basal, 1, 15, 30, 45, 60 and 120 min.) for the assessment of myocardial contractility function. In addition, creatine kinase-M and B subunits (CK-MB), lactate dehydrogenase (LDH1) and Na(+)-K(+)-ATPase activity along with oxidative tissue biomarkers (i.e. thio-barbituric acid reactive substances (TBARS) and reduced glutathione (GSH)) changes were estimated. The I/R of myocardium produced decrease in coronary flow rate; increase in CK-MB, LDH1 and Na(+)-K(+)-ATPase activity along with increase in TBARS and decrease in GSH levels as compared to normal group. The treatment with vitamin P (100 mg/kg) and digoxin (500 µg/kg) have produced a significant (p < 0.05) ameliorative effect against I/R induced above functional, metabolic and tissue biomarkers changes. Vitamin P has an ameliorative potential against I/R induced myocardial functional changes. It may be due to its free radical scavenging and anti-infarct property via inhibition of Na(+)-K(+)-ATPase activity. Therefore, it can be used as a potential therapeutic medicine for the management of cardiovascular disorders.

Bone loss at the os calcis compared with bone loss at the knee in individuals with spinal cord injury.

BACKGROUND/OBJECTIVE: The objective of this study was to document acute bone loss at the os calcis and compare it with bone loss at the knee following spinal cord injury (SCI) as a potential proxy for bone loss in individuals with SCI. METHODS: Bone mineral density (BMD) was measured by dual energy x-ray absorptiometry (DEXA) at the knee and os calcis, which also was assessed by ultrasound in 6 individuals--5 with complete SCI and 1 with incomplete SCI--at means of 33.5 and 523 days following injury. RESULTS: Bone mineral was progressively greater as measured from proximal to distal sites. The net average BMD of the knee declined 24% (P = 0.017). The distal femur lost 27% (P = 0.038) and the proximal tibia lost 32% (P = 0.015), whereas the os calcis lost 38% (P = 0.001) as measured by DEXA and 49% (P < 0.001) as estimated from ultrasound. The mean loss of 24% at the knee was significantly different from the loss percentages at the os calcis as measured by both techniques: DEXA (P = 0.036) and ultrasound (P = 0.043). Differences between annualized loss rates at the knee and the os calcis measured by both techniques also were significant: DEXA (P = 0.032) vs ultrasound (P = 0.038). However, annualized loss rates demonstrated the same trend for differential loss at the sites examined in the 5 individuals with complete injuries but not for the 1 participant with an incomplete injury. The loss rates were similar for the complete and incomplete participants at the os calcis, but not at the knee. CONCLUSION: The BMD of the os calcis declined 38% by DEXA and 49% by ultrasound compared with 24% at the knee when measured 1 to 1.5 years after injury. BMD of the os calcis and distal femur measured by DEXA in persons with complete SCI were highly correlated (r = 0.84, P < 0.0001).