Nano-bio convergence unveiled: Systematic review on quantum dots-protein interaction, their implications, and applications.

Quantum dots (QDs) are semiconductor nanocrystals (2-10 nm) with unique optical and electronic properties due to quantum confinement effects. They offer high photostability, narrow emission spectra, broad absorption spectrum, and high quantum yields, making them versatile in various applications. Due to their highly reactive surfaces, QDs can conjugate with biomolecules while being used, produced, or unintentionally released into the environment. This systematic review delves into intricate relationship between QDs and proteins, examining their interactions that influence their physicochemical properties, enzymatic activity, ligand binding affinity, and stability. The research utilized electronic databases like PubMed, WOS, and Proquest, along with manual reviews from 2013 to 2023 using relevant keywords, to identify suitable literature. After screening titles and abstracts, only articles meeting inclusion criteria were selected for full text readings. This systematic review of 395 articles identifies 125 articles meeting the inclusion criteria, categorized into five overarching themes, encompassing various mechanisms of QDs and proteins interactions, including adsorption to covalent binding, contingent on physicochemical properties of QDs. Through a meticulous analysis of existing literature, it unravels intricate nature of interaction, significant influence on nanomaterials and biological entities, and potential for synergistic applications harnessing both specific and nonspecific interactions across various fields.

Smart Magnetic Nanocarriers for Codelivery of Nitric Oxide and Doxorubicin for Enhanced Apoptosis in Cancer Cells.

Extremely short half-life therapeutic molecule nitric oxide (NO) plays significant roles in the functioning of various physiological and pathological processes in the human body, whereas doxorubicin hydrochloride (DOX) is a clinically important anticancer drug widely used in cancer chemotherapy. Thus, the intracellular delivery of these therapeutic molecules is tremendously important to achieve their full potential. Herein, we report a novel approach for the development of highly water-dispersible magnetic nanocarriers for codelivery of NO and DOX. Primarily, bifunctional magnetic nanoparticles enriched with carboxyl and thiol groups were prepared by introducing cysteine onto the surface of citrate-functionalized Fe3O4 nanoparticles. DOX was electrostatically conjugated onto the surface of bifunctional nanoparticles via carboxyl moieties, whereas the thiol group was further nitrosated to provide NO-releasing molecules. The developed magnetic nanocarrier exhibited good aqueous colloidal stability, protein resistance behavior, and high encapsulation efficacy for NO (65.5%) and DOX (85%), as well as sustained release characteristics. Moreover, they showed superior cytotoxicity toward cancer (A549 and MCF-7) cells via apoptosis induction over normal (WI26VA4) cells. Specifically, we have developed magnetic nanocarriers having the capability of dual delivery of NO and DOX, which holds great potential for combinatorial cancer treatment.

Formation of Self-Assembled Nanowires from Copper Nanoparticles Synthesized by the Electro-Explosion of Wires Technique-Study of the Time-Dependent Structural and Functional Evolution.

We report here the formation of Cu nanowires (CuNWs) from Cu nanoparticles (CuNPs) by a self-assembly process. The CuNPs were synthesized by the electro-explosion of wire (EEW) technique that included nonequilibrium processes for the synthesis. Structural evolution in terms of aggregation or nanowire formation in the samples was observed when the CuNPs were kept for a month after synthesis in a glass vial without the application of any external driving force. The emergence of tangled CuNWs was noticed at the bottom of the vials only when no agitation or aeration was allowed. The nanowires were characterized using transmission electron microscopy (TEM) and X-ray diffraction (XRD). Thermal oxidation of the nanowire samples implied that they could convert into rod-shaped structures. Loss of functionality was also observed in the hemoglobin precipitation study conducted to compare the activity of freshly prepared CuNPs and CuNWs. From the above observations, we conclude that the CuNP, after synthesis, possesses a huge amount of energy, and attainment of equilibrium occurs through either aggregation (clustering) or ordered self-assembly, depending on the conditions applied.

Multifunctional ZnO nanostructures: a next generation nanomedicine for cancer therapy, targeted drug delivery, bioimaging, and tissue regeneration.

Zinc oxide nanostructures (ZnO NSs) are one of the most versatile and promising metal oxides having significant importance in biomedical fields, especially for therapeutic and diagnostic purposes. ZnO possesses unique physio-chemical and biological properties such as photo-chemical stability, corrosion resistance, mechanical properties, biocompatibility, higher targeting capability, and ROS-triggered cytotoxicity. These ZnO NSs have enhanced potential for various biomedical applications such as cancer therapy, drug delivery, bioimaging, tissue engineering, etc. Furthermore, ZnO possesses excellent luminescent properties that make it useful for bioimaging and image-guided targeted drug delivery, thereby reducing the unwanted side effects of chemotherapeutic agents. Besides, these characteristics, enhanced permeability and retention effect, electrostatic interaction, ROS production, and pH-dependent dissolution of ZnO also make it potential aspirant as therapeutic that are suggested as key parameters for cytotoxic and cell death mechanismsviaapoptosis, autophagy, and mitophagy mechanisms. Here, the recent progress and advances of ZnO NSs in bioimaging, drug delivery, and tissue engineering are discussed along with the advantages, limitations, and future advancement for biological applications.

Transition in the ages at key reproductive events and its determinants in India: evidence from NFHS 1992-93 to 2019-21.

INTRODUCTION: Reproductive health events have changed fertility and family planning needs, depicting the changing life patterns of women and the population to which they belong. Understanding the pattern at which these events occur helps in understanding the fertility pattern, family formation and the idea about health essential needs for women. This paper attempts to see the variation in reproductive events (first cohabitation, first sex and first birth) over three decades and also to see potential contributing factors among the reproductive age group of women using secondary data from Data Source: All rounds of the National Family Health Survey (1992-93 to 2019-2021) have been utilized. METHODS AND RESULTS: Cox Proportional Hazard Model illustrates that all regions have initiated their first birth later than women who belong to the east region similar pattern has been obtained for first cohabitation and first sex except for the central region. Multiple Classification Analysis (MCA) depicts the increasing pattern in the predicted mean age at first cohabitation, sex and birth for all demographic characteristics; the highest increment was found in SC women, Uneducated women and Muslim women. Kaplan Meier Curve demonstrates that women with no education, primary or secondary education are shifting towards higher educated women. Most importantly, the results of the multivariate decomposition analysis (MDA) revealed that education played the largest contribution among the compositional factors in the overall increase in mean ages at key reproductive events. CONCLUSIONS: Though reproductive health has long been essential in women's lives, they are still very confined to specific domains. Over time the government has formulated several proper legislative measures relating to various domains of reproductive events. However, given that the large size and heterogeneity in social and cultural norms result in changing ideas and choices regarding the initiation of reproductive events, national policy formulation needs to be improved or amended.

Size- and surface functionalization-driven molecular interaction of CdSe quantum dots with jack bean urease: multispectroscopic, thermodynamic, and AFM approach.

Quantum dots (QDs) with distinctive optical properties have been extensively researched and developed for usage in solar cells, imaging, drug delivery, cellular targeting, etc. But the inevitable production of QDs can lead to their unavoidable release and increased environmental concentration. Depending on morphological and surface properties, QDs at the nano-bio interface considerably impact the activity and structure of bio-molecules. The present study investigates the interaction of metalloenzyme jack bean urease (JBU) and bi-sized CdSe QDs (2.43 nm and 3.63 nm), surface-functionalized to mercaptopropionic acid (MPA) (-COOH), L-cysteine (CYS), L-glutathione (GSH), N-acetyl L-cysteine (NAC) (-COOH, -NH2), and cysteamine hydrochloride (CYST) (-NH2) to assess any alterations in JBU's binding, microenvironment, structure, exciton lifetime, and activity. JBU catalyzes the hydrolysis of urea to produce ammonia and carbon dioxide; any changes in its properties could threaten the survival of several microbes and plants. Spectroscopy techniques such as UV-Vis, fluorescence, circular dichroism, synchronous, time-resolved fluorescence, atomic force microscopy, and JBU activity assay were studied. Results suggested highly spontaneous and energy-favored interactions, which involved static quenching and hydrophobic forces of varied magnitude, dependent on QDs properties. The size, surface modifications, and dosage of QDs significantly impacted the secondary structure and activity of JBUs. Even though the larger sizes of the relevant modifications demonstrated stronger binding, the smaller sizes had the greatest impact on α-helicity and activity. CYST-capped QDs with an average number of the binding site (n) = 1, reduced α-helicity by 16% and activity by 22-30% at 7 nM concentration. In contrast, MPA-capped QDs with n < 1 had the least effect on α-helical structure and activity. The smaller GSH-capped QDs increased the activity by 9%, via partially restoring JBU's α-helical content. The study thus thoroughly analyzed the impact of varied-size and surface-functionalized QDs on the structure and function of JBU, which can be exploited further for several biomedical applications.

The supply is there. So why can't pregnant and breastfeeding women in rural India get the COVID-19 vaccine?

Despite COVID-19 vaccines being available to pregnant women in India since summer 2021, little is known about vaccine uptake among this high need population. We conducted mixed methods research with pregnant and recently delivered rural women in northern India, consisting of 300 phone surveys and 15 in-depth interviews, in November 2021. Only about a third of respondents were vaccinated, however, about half of unvaccinated respondents reported that they would get vaccinated now if they could. Fears of harm to the unborn baby or young infant were common (22% of unvaccinated women). However, among unvaccinated women who wanted to get vaccinated, the most common barrier reported was that their health care provider refused to provide them the vaccine. Gender barriers and social norms also played a role, with family members restricting women's access. Trust in the health system was high, however, women were most often getting information about COVID-19 vaccines from sources that they did not trust, and they knew they were getting potentially poor-quality information. Qualitative data shed light on the barriers women faced from their family and health care providers but described how as more people got the vaccine that norms were changing. These findings highlight how pregnant women in India have lower vaccination rates than the general population, and while vaccine hesitancy does play a role, structural barriers from the health care system also limit access to vaccines. Interventions must be developed that target household decision-makers and health providers at the community level, and that take advantage of the trust that rural women already have in their health care providers and the government. It is essential to think beyond vaccine hesitancy and think at the system level when addressing this missed opportunity to vaccinate high risk pregnant women in this setting.

Immobilization of protein on Fe3O4 nanoparticles for magnetic hyperthermia application.

We report a facile approach for the preparation of protein conjugated glutaric acid functionalized Fe3O4 magnetic nanoparticles (Pro-Glu-MNPs), having improved colloidal stability and heating efficacy. The Pro-Glu-MNPs were prepared by covalent conjugation of BSA protein onto the surface of glutaric acid functionalized Fe3O4 magnetic nanoparticles (Glu-MNPs) obtained through thermal decomposition. XRD and TEM analyses confirmed the formation of crystalline Fe3O4 nanoparticles of average size ~5 nm, whereas the conjugation of BSA protein to them was evident from XPS, FTIR, TGA, DLS and zeta-potential measurements. These Pro-Glu-MNPs showed good colloidal stability in different media (water, phosphate buffer saline, cell culture medium) and exhibited room temperature superparamagnetism with good magnetic field responsivity towards the external magnet. The induction heating studies revealed that the heating efficacy of these Pro-Glu-MNPs was strongly reliant on the particle concentration and their stabilizing media. In addition, they showed enhanced heating efficacy over Glu-MNPs as surface passivation by protein offers colloidal stability to them as well as prevents their aggregation under AC magnetic field. Further, Pro-Glu-MNPs are biocompatible towards normal cells and showed substantial cellular internalization in cancerous cells, suggesting their potential application in hyperthermia therapy.

Glutamic acid-coated Fe3O4 nanoparticles for tumor-targeted imaging and therapeutics.

We have developed surface functionalised Fe3O4 magnetic nanoparticles (MNPs) based system that can be used for tumor-targeted multimodal therapies and MR imaging. Biocompatible, non-essential amino acid (glutamic acid) was introduced onto the surface of Fe3O4 MNPs to provide functional sites for binding of chemotherapeutic drugs. These glutamic acid-coated Fe3O4 MNPs (GAMNPs) exhibit good water-dispersibility, magnetic responsivity and pH dependent charge conversal feature. The magnetic core as well as organic shell of GAMNPs was characterized by XRD, TEM, DLS, FTIR, PPMS and UV-visible spectroscopy and zeta-potential analyzer etc. The broad spectrum anticancer drugs, doxorubicin hydrochloride (DOX) and methotrexate (MTX) were electrostatically and covalently conjugated to the surface of GAMNPs, respectively for combination chemotherapy. These dual drugs loaded system (DOX-MTX-GAMNPs) shows pH dependent release behaviour of both the drugs and enhanced toxicity towards breast cancer cell line (MCF-7) as compared to their individual treatment. Fluorescence microscopy and flow cytometric analyses confirmed the successful uptake of drug loaded system into MCF-7 cell lines. Further MTX being analogue of folic acid, its co-delivery with DOX would help in internalization of both the drugs into MCF-7 cells. These GAMNPs also show good heating efficiency under AC magnetic field (Intrinsic loss power, ILP = 0.95 and 0.73 and 0.48 nHm2/Kg at Fe concentration of 0.5, 1 and 2 mg/ml, respectively) and transverse relaxivity (r2 = 152 mM-1 s-1) indicating their potential capability for hyperthermia therapy and MRI tracking. Furthermore, it has been observed that the combination of chemotherapeutic drugs and hyperthermia leads to an enhancement of cytotoxicity in MCF-7 cells.

UV Lithography-Assisted Fabrication of Low-Cost Copper Electrodes Modified with Gold Nanostructures for Improved Analyte Detection.

An in-house UV lithography setup has been optimized to fabricate low-cost disposable electrochemical sensing Cu electrodes using a copper clad board. In view of the high oxidation probability of copper, the low-cost electrodes were modified using different gold nanostructures and a conducing polymer PEDOT:PSS to attain maximal signal output and improved shelf-life. Zero-dimensional (0D) gold nanoparticles (∼40 nm) and three-dimensional (3D) gold nanoflowers (∼38 nm) mixed with PEDOT:PSS were used as signal-enhancing conductors for the ultrasensitive detection of our model contaminant, methylene blue dye (MB). The bare copper electrode was sensitive to MB, linearly within the range of 4-100 µM, with a limit of detection of 3.49 µM. While for gold nanoparticle-PEDOT:PSS-modified electrode, the sensitivity of the electrode was found to increase linearly in the range of 0.01-0.1 µM, and for gold nanoflowers-PEDOT:PSS, the sensitivity achieved was 0.01-0.1 µM with the LOD as 0.0022 µM. For a PEDOT:PSS-modified Cu electrode, used as a comparative to study the contributing role of gold nanostructures towards improved sensitivity, the linearity was found to be in the range of 0.1-1.9 µM with the LOD as 0.0228 µM. A 6 times improvement in signal sensitivity for the nanoflower-PEDOT:PSS electrode compared to the nanoparticle-PEDOT:PSS-modified electrode indicates the influence of nanoparticle shape on the electrode efficiency. 3D gold nanoflowers with a large surface area-to-volume ratio and a high catalytic activity prove to be a superior choice for electrode modification.

A method to detect immunoreactions on the basis of current vs. concentration slope - an electrochemical approach.

The emergence of novel infectious diseases is rising with time and is a major threat to the society. The recent outbreak of infectious coronavirus disease has made a huge impact in our lives. The massive outbreak of the disease revealed that there is room for development of new diagnostics tools and methods to screen huge numbers of samples in the shortest possible time. Our current work relates to an electronic diagnostic system and method that rapidly detects the presence of an antigen in solution. Our designed system is capable of separating the immunocomplex formation on the basis of the slope it produces in contrast to the controls, when oxidation peak current is plotted against the concentration of the reactant after electrochemistry measurement. In this system, antibody conjugated copper nanoparticles synthesized by the electroexplosion method has played the key role. The values of the slopes of copper nanoparticles (CuNPs) was found to be -3.7637, whereas those for CuNP conjugated Antibody and CuNPAntibodyAntigen were -2.3044 and -0.8332, respectively. Hence, the current method could become one of the easiest and fastest method for the electronic detection of an immune reaction and a good replacement for the time-consuming, label-based assays in multistep reaction.

Defect-Mediated Reactive Oxygen Species Generation in Mg-Substituted ZnO Nanoparticles: Efficient Nanomaterials for Bacterial Inhibition and Cancer Therapy.

Mg-substituted ZnO nanoparticles (MgZnO NPs) were synthesized by a soft chemical approach and were well-characterized by X-ray diffraction, transmission electron microscopy, UV-visible spectroscopy, and photoluminescence spectroscopy. The absorption and photoluminescence spectra show that substitution of Mg ions results in the widening of the band gap and a significant enhancement in the concentration of defects in ZnO NPs. A systemic study of generation of reactive oxygen species (ROS) under dark, daylight, and visible light conditions suggests that the aqueous suspension of MgZnO NPs generates a higher level of ROS because of the surface defects (oxygen vacancies). This capability of MgZnO NPs makes them a more promising candidate for the inhibition of bacterial growth and for killing of cancer cells as compared to pure ZnO NPs, possibly because of the enhanced interaction and accumulation of MgZnO NPs in the cytoplasm or cell membrane in the presence of both Zn2+ and Mg2+ ions. Further, MgZnO NPs exhibit excellent selective killing of nasopharyngeal carcinoma cells (KB) and cervical cancer cells (HeLa) with minimal toxicity to normal fibroblast cells (L929). The results suggest that the generation of ROS and Zn2+ ions are possibly responsible for the higher activity toward the depolarization of cell membrane potential, the lipid peroxidation in bacterial cells, depolarization of the mitochondrial membrane, and cell cycle arrest in the S phase in cancer cells.

Immunohistochemical evaluation of tumor angiogenesis and the role of mast cells in oral squamous cell carcinoma.

BACKGROUND: Increased angiogenesis has been associated with neoplastic progression, metastasis and outcome in several studies and in a number of malignancies. Among the various host immune cells, mast cells have been implicated in tumor progression by promoting angiogenesis. The aim of this study is to examine the relationship between angiogenesis, mast cells with that of the normal oral mucosa (NOM) and oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: The study was conducted using routine haematoxylin and eosin staining procedure and included immunohistochemical staining for microvessels and toluidine blue staining for mast cells. RESULTS: The microvessel density (MVD) and mast cell density (MCD) of two groups (NOM and OSCC). The MVD and MCD in OSCC ranged from 59.18 to 263.31 microvessel/mm 2 and 41.65 to 193.28 cells/mm 2 respectively with mean (±standard deviation) 161.73 ± 48.27 microvessel/mm 2 and 83.59 ± 40.67 cells/mm 2. In both NOM and OSCC, the mean MCD was comparatively lower as compared to respective MVD (MCD < MVD) and comparatively lower in NOM as compared to OSCC (normal < OSCC). CONCLUSION: A significant correlation is present between MCD and MVD in OSCC and also that both these entities are significantly increased in the disease process when compared to that of the NOM.

Vacancy-Driven Gelation Using Defect-Rich Nanoassemblies of 2D Transition Metal Dichalcogenides and Polymeric Binder for Biomedical Applications.

A new approach of vacancy-driven gelation to obtain chemically crosslinked hydrogels from defect-rich 2D molybdenum disulfide (MoS2 ) nanoassemblies and polymeric binder is reported. This approach utilizes the planar and edge atomic defects available on the surface of the 2D MoS2 nanoassemblies to form mechanically resilient and elastomeric nanocomposite hydrogels. The atomic defects present on the lattice plane of 2D MoS2 nanoassemblies are due to atomic vacancies and can act as an active center for vacancy-driven gelation with a thiol-activated terminal such as four-arm poly(ethylene glycol)-thiol (PEG-SH) via chemisorption. By modulating the number of vacancies on the 2D MoS2 nanoassemblies, the physical and chemical properties of the hydrogel network can be controlled. This vacancy-driven gelation process does not require external stimuli such as UV exposure, chemical initiator, or thermal agitation for crosslinking and thus provides a nontoxic and facile approach to encapsulate cells and proteins. 2D MoS2 nanoassemblies are cytocompatible, and encapsulated cells in the nanocomposite hydrogels show high viability. Overall, the nanoengineered hydrogel obtained from vacancy-driven gelation is mechanically resilient and can be used for a range of biomedical applications including tissue engineering, regenerative medicine, and cell and therapeutic delivery.

Visible light driven mesoporous Ag-embedded ZnO nanocomposites: reactive oxygen species enhanced photocatalysis, bacterial inhibition and photodynamic therapy.

We present here the multitasking capabilities of Ag-embedded ZnO nanocomposites (Ag-ZnO NCs), which include the photocatalytic degradation of organic dyes, bacterial inhibition, and cancer therapeutics. Ag-embedded ZnO nanocomposites (Ag-ZnO NCs) of mesoporous spherical morphology (size ∼ 150 ± 50 nm) are successfully synthesized by a facile and single step soft-chemical approach. To understand the effect of Ag loading on multitasking properties, Ag-ZnO NCs are synthesized with different wt% of Ag. It was found that Ag5-ZnO NCs (5 wt% of Ag) showed excellent solar light-induced photocatalytic degradation properties against both cationic as well as anionic dyes. In addition, the presence of Ag in these NCs makes them strongly antibacterial, and kills 100% Escherichia coli (E. coli) cells within 2 hours (under dark), and within 30 min (under solar light). The enhanced photocatalytic and antibacterial activity of Ag-ZnO NCs is due to the anchoring of Ag NPs onto ZnO as well as minor substitution of Ag ions in the lattice of ZnO. This produces abundant charge carriers and generates significantly enhanced reactive oxygen species (ROS), which seem responsible for the multitasking properties. Furthermore, the cytotoxic study shows that Ag5-ZnO NCs kill oral carcinoma (KB) cells under visible light irradiation, and work as photosensitizers towards the photodynamic therapy of cancer due to the excellent photocatalytic activity. The high ROS concentration depolarizes the mitochondrial membrane potential, which in turn initiates apoptosis in oral carcinoma (KB) cells inducing cell death. Therefore, the as-prepared mesoporous Ag-ZnO NCs show great promise in waste water treatment, and cancer therapeutics.

Correlation of mast cells in different stages of human periodontal diseases: Pilot study.

AIMS AND OBJECTIVES: The aim of this study was to evaluate and correlate the relationship between mast cells counts and different stages of human periodontal diseases. MATERIALS AND METHODS: The study sample comprised 50 patients, which were divided into three groups, consisting of 10 cases of clinically healthy gingival tissues (control group) 20 cases of dental plaque-induced gingivitis with no attachment loss and 20 cases of localized chronic periodontitis (LCP) characterized by the loss of periodontal support. The samples for control group were obtained during tooth extractions for orthodontic reasons. The specimens were immediately fixed in 10% neutral buffered formalin. CONCLUSION: In this study, LCP cases had higher mast cell counts compared to gingivitis sites or healthy tissues. Increased mast cell counts in the progressing sites of periodontal diseases may indicate the importance of these cells in the progression of chronic periodontitis.

A pH-responsive folate conjugated magnetic nanoparticle for targeted chemo-thermal therapy and MRI diagnosis.

Polyacrylic acid functionalized Fe3O4 nanoparticles (PAA-MNPs) of average size of 10 nm are prepared by a simple soft chemical approach. These PAA-MNPs are conjugated with folic acid through peptide bonding between the carboxylic group on the surface of PAA-MNPs and the amine group of folic acid. The good colloidal stability of FA conjugated MNPs makes it a promising candidate for targeted drug delivery, hyperthermia and as a MRI contrast agent with a transverse relaxivity R2 value of 105 mM(-1) s(-1). Folic acid conjugated magnetic nanoparticles (FA-MNPs) achieved ∼ 95% loading efficiency of doxorubicin (DOX) which could be due to strong electrostatic interaction of highly negatively charged FA-MNPs and the positively charged DOX. The drug release study shows a pH-dependent behavior and is higher in acidic pH (4.3 and 5.6) as compared to the physiological pH (7.3). Flow cytometry and confocal microscopic image analysis reveal that around 75-80% of HeLa cells undergo apoptosis due to DNA disintegration upon incubation with DOX-MNPs for 24 h. DOX-MNPs exhibit the synergistic effect due to the combination of DOX induced apoptosis and magnetic hyperthermia treatment (MHT) which enhance the cell death ∼ 95.0%. Thus, this system may serve as a potential pH sensitive nanocarrier for synergistic chemo-thermal therapy as well as a possible MRI contrast agent.

PEGylated FePt-Fe3O4 composite nanoassemblies (CNAs): in vitro hyperthermia, drug delivery and generation of reactive oxygen species (ROS).

Chemothermal therapy is widely used in clinical applications for the treatment of tumors. However, the major challenge is the use of a multifunctional nano platform for significant regression of the tumor. In this study, a simple synthesis of highly aqueous stable, carboxyl enriched, PEGylated mesoporous iron platinum-iron(ii,iii) oxide (FePt-Fe3O4) composite nanoassemblies (CNAs) by a simple hydrothermal approach is reported. CNAs exhibit a high loading capacity ∼90 wt% of the anticancer therapeutic drug, doxorubicin (DOX) because of its porous nature and the availability of abundant negatively charged carboxylic groups on its surface. DOX loaded CNAs (CNAs + DOX) showed a pH responsive drug release in a cell-mimicking environment. Furthermore, the release was enhanced by the application of a alternating current magnetic field. CNAs show no appreciable cytotoxicity in mouse fibroblast (L929) cells but show toxic effects in cervical cancer (HeLa) cells at a concentration of ∼1 mg mL(-1). A suitable composition of CNAs with a concentration of 2 mg mL(-1) can generate a hyperthermic temperature of ∼43 °C. Also, CNAs, because of their Fe and Pt contents, have an ability to generate reactive oxygen species (ROS) in the presence of hydrogen peroxide inside the cancer cells which helps to enhance its therapeutic effects. The synergistic combination of chemotherapy and ROS is very efficient for killing cancer cells.

Fluorescent ZnO for imaging and induction of DNA fragmentation and ROS-mediated apoptosis in cancer cells.

Fluorescein isothiocyanate (FITC)-encapsulated ZnO nanocomposite has been synthesized using the soft chemical approach. X-ray diffraction reveals the formation of highly crystalline single-phase hexagonal wurtzite nanostructure. TEM and SEM micrographs indicate the formation of spherical porous nanoassembly of ZnO of size ∼ 100-400 nm. On the other hand, FITC-ZnO nanocomposite is spherical and porous but with a uniform size of ∼150 nm. The size of single particles is ∼20 nm for the ZnO nanoassembly and ∼15 nm for FITC-ZnO nanocomposite. The UV-visible, fluorescence, FTIR and XPS spectra confirm the formation of FITC-ZnO nanocomposite. The FITC-ZnO nanocomposite demonstrates excellent selectivity in preferential killing of cervical (HeLa) and breast (MCF-7) cancer cells with minimal toxicity to normal fibroblast cells (L929). Apoptotic cells are observed and analyzed by confocal microscopy and flow cytometry. Our results show that cytotoxicity of FITC-ZnO nanocomposite towards cancer cells is due to the generation of reactive oxygen species (ROS) and preferential dissolution of Zn2+ ions in an acidic cancer microenvironment. Furthermore, generated ROS and dissolved Zn+2 ions induce cellular apoptosis, DNA fragmentation, and depolarization of mitochondrial membrane and cell cycle arrest in S phase. The FITC encapsulated multifunctional ZnO nanocomposite can be used as smart nanostructures for cell imaging and cancer therapy.

Palatogingival groove - a silent killer: Treatment of an osseous defect due to it.

A male patient of 21 years of age reported to the Department of Periodontology and Implantology with a chief complain of pus discharge in both right and left upper lateral incisors. On clinical examination a deep pocket of about 10-14 mm was noticed in both lateral incisors. Radiographic interpretation shows a teardrop-shaped radiolucency in both the laterals giving suspicion of palatogingival groove, which was later discovered and treated surgically.