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Anthraquinone class of compounds possesses a broad spectrum of therapeutic applications. Cancer cell targeting ability, together with photogeneration of reactive oxygen species, renders anthraquinones an interesting class of photosensitizers for photodynamic therapy (PDT). Screening of newer compounds for better singlet oxygen generation is of current interest to improve the practical usability in PDT. In this study, we investigate the photodynamic activity of nine commercially available anthraquinones, using EPR spectroscopy and computational techniques, to identify the role of substituents on singlet oxygen yield. Three anthraquinone derivatives, 1,5-diaminoanthraquinone, 15-dihydroxyanthraquinone and 1,2,7-trihydroxyanthraquinone, showed highest singlet oxygen quantum yield (0.21, 0.18 and 0.15, respectively) relative to Rose Bengal. Time-dependent density functional theory calculations indicate the singlet oxygen quantum yield of anthraquinones inversely correlate well with the excited singlet-triplet (S1-T1) energy gap. Electron-donating substituents present at positions 1, 2 and 5 of anthraquinone seem to reduce the S1-T1 energy gap, facilitating inter-system crossing and the production of singlet oxygen. This would greatly aid in the design of newer anthraquinone-based photosensitizers. This study also highlights the suitability of 1,5-diaminoanthraquinone for PDT applications as demonstrated by in vitro experiments of photoinduced DNA cleavage and photocytotoxicity in Dalton's lymphoma ascites.

Zinc-alloyed cadmium selenide (Cd/ZnSe) quantum dots (QDs) were synthesised in a wet chemical method using thioglycolic acid as a stabilising agent. This facile synthesis method does not require high-temperature or inert gas (argon or nitrogen) atmosphere as required in prevailing methods. Also, this method does not require pyrophoric compounds such as trioctylphosphine (TOP) and trioctylphosphine oxide (TOPO). The synthesised QDs were characterised using a spectrofluorometer, Fourier transform infrared (FT-IR) spectrometer, zeta potential, fluorescence lifetime spectrometer, ICP-OES, and selected area electron diffraction (SAED). The synthesised QDs were spherical with an average diameter of 5.08 nm and has a carboxyl group on their surface making them readily soluble in water and are biologically compatible. The QDs were evaluated for visible light–induced photocatalysis of Rhodamine 6G, and around 68% of the dye was degraded with 60 min of visible light irradiation. The synthesised QDs were tested for its toxicity in Danio rerio embryos including survival percentage, percentage of hatching, heartbeat counts and body length. Based on the toxicity evaluation, along with the presence of the carboxyl group on their surface, these QDs can harbour targeting molecules which will serve as a less toxic molecular imaging probe.

Bone is a flexible and electro active tissue that is vulnerable to various traumatic injuries. The self-healing of damaged bone tissue towards reconstruction is limited due to the lack of proper niche compliances. Nevertheless, the classical grafting techniques like autograft/allograft for bone repair pose challenges like bacterial infections and donor-site morbidity with unsatisfactory outcomes. The use of appropriate biomaterial with osteogenic potential can meet these challenges. In this regard, bioactive glass ceramics is widely used as a bone filler or graft material because of its bonding affinity to bone leading towards bone reconstruction applications without the challenge of post implant infections. Hence, the current study is aimed at addressing this potentiality of zinc (Zn) for doped the bioglass at nano-scale advantages for bone tissue repair. Since, Zn has been demonstrated to have not only antibacterial property but also the stimulatory effect on osteoblasts differentiation, mineralization by enhancing the osteogenic genes expression. In view of these, the present study is focused on sol–gel synthesis and pysico-chemical characterization of Zinc-doped bioglass nanoparticles (Zn-nBGC) and also analyzing its biological implications. The surface morphological and physiochemical characterizations using SEM, EDX, FT-IR and XRD analysis has shown the increased surface area of Zn-nBGC particles providing a great platform for biomolecular interaction, cytocompatibility, cell proliferation and osteogenic differentiation. The obtaining hydroxy apatite groups have initiated in vitro mineralization towards osteogenic lineage formation. Zn has not only involved in enhancing cellular actions but also strengthen the ceramic nanoparticles towards antibacterial application. Hence the finding suggests a biomaterial synthesis of better biomaterial for bone tissue engineering application by preventing post-operative bacterial infection.

Colorectal cancer found to be the most commonly occurring cancer worldwide which can be prevented by screening and its curable if diagnosed early. Lynch syndrome/HNPCC being an autosomal genetic disease and propensity in forming colorectal cancer is inherited wherein genomic instabilities and epigenetic changes are being the characteristic forms in hereditary cancers. It is very important to determine the polymorphism in several DNA repairing genes such as ATM, RAD51, XRCC2, XRCC3 and XRCC9 to study the risk exploring both the prognosis and the developing of colorectal cancer. The role of ATM gene has been studied which involves in the hereditary transfer of colorectal cancer associated with other related cancers such as stomach, lung and breast cancers. ATM found to be the mutation target and also a modifier gene with more risk of developing the disease by its polymorphism in variant of ATM D1853N. It was identified that ATM gene polymorphism did not drastically change HNPCC age of onset. ATM expression levels were studied and it has been concluded that the complete loss of ATM expression resulted in a propensity of worse survival and no better prognosis with increase in mortality rate. This ATM gene might be considered to be a predicted biomarker in colorectal cancer. (www.actabiomedica.it)

Three different stabilizing agents, namely, l -cysteine, Thioglycolic acid and cysteamine hydrochloride were used to synthesize Cd(Zn)Se quantum dots (QDs). It was characterized using UV-vis spectroscopy, x-ray diffraction (XRD) and transmission electron microscopy (TEM). The non-linear optical properties (non-linear absorption and non-linear refraction) of synthesized Cd(Zn)Se quantum dots were studied with z-scan technique using diode pumped continuous wavelaser system at a wavelength of 532 nm. Our (organic) synthesized quantum dots showed optical properties similar to the inorganic materials reported elsewhere.

Bone, a highly dynamic connective tissue, consist of a bioorganic phase comprising osteogenic cells and proteins which lies over an inorganic phase predominantly made of CaPO4 (biological apatite). Injury to bone can be due to mechanical, metabolic or inflammatory agents also owing pathological conditions like fractures, osteomyelitis, osteolysis or cysts may arise in enameloid, chondroid, cementum, or chondroid bone which forms the intermediate tissues of the body. Bone tissue engineering (BTE) applies bioactive scaffolds, host cells and osteogenic signals for restoring damaged or diseased tissues. Various bioceramics used in BTE can be bioactive (like glass ceramics and hydroxyapatite bioactive glass), bioresorbable (like tricalcium phosphates) or bioinert (like zirconia and alumina). Limiting the size of these materials to nano-scale has resulted in a higher surface area to volume ratio thereby improving multi-functionality, solubility, surface catalytic activity, high heat and electrical conductivity. Nanoceramics have been found to induce osteoconduction, osteointegration, osteogenesis and osteoinduction. The present review aims at summarizing the interactions of nanoceramics and osteoblast/stem cells for promoting the proliferation and differentiation of the osteoblast cells by nanoceramics as superior bone substitutes in bone tissue engineering applications.

Alzheimer’s disease (AD) accounts for more than 65% of dementia cases, characterized by progressive cognitive deficits, which include apraxia, differential impairment of recall memory, and language disturbances accompanied with other symptoms, such as psychosis, agitation, hallucinations, delusions, anxiety, and depression.1–5 The progression of AD is due to several factors: severe tau-deposition and augmentation by oxidative damage, cholinergic neuronal death, beta-amyloid deposition, and microglial inflammation were found to be the cause of AD.6–9 The early stages of AD are determined by pathology in subjects with mild cognitive impairment (MCI), including the neurofibrillary tangles, plaques, and loss of basal forebrain cholinergic neurons.10 According to studies based on the AD pathogenesis, the accumulation of Aβ plaques in the brain is followed by the neurofibrillary tangles formation containing the tau protein, which results in the imbalance of Aβ plaque deposition.11 The most commonly affected brain areas include the temporal lobe cortex and hippocampal regions with neurofibrillary tangles.12 Gray matter loss in subjects with the cognitive decline has been found to be specific in cortical areas, such as the parietal, hippocampal, precuneus, and medial temporal lobes, resulting in high medial temporal atrophy.13 Recent studies reveal that evaluation of cerebrospinal fluid biomarkers using positron-emission tomography (PET) imaging has the ability to characterize the level of amyloid burden and the degree of neurodegenerative changes in AD patients.14 Brain morphometry using magnetic resonance imaging (MRI) is a well-known modality for the diagnosis and prognosis of AD.15 MRI of the brain can help effective visualization of the medial temporal lobe structures that are involved in MCI.16 Atrophy of hippocampus has been reported to be the most significant structural predictor involved in the conversion of MCI to AD.17 The most common structural MRI markers were the hippocampal and medial temporal atrophies, which are known to be involved in the progression of AD.18 Functional magnetic resonance imaging (fMRI) has made significant progress toward brain mapping and neural activity studies.19 The fMRI records the blood-oxygen-level-dependent (BOLD) signal changes with good spatial resolution to map the neuronal activity in the whole brain.20 Resting-state functional magnetic resonance imaging (rs-fMRI) measures the low-frequency fluctuations (LFFs) (