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.

Differential impact of COVID-19 on mental health and burnout

BACKGROUND

There may be differential impact of the COVID-19 pandemic on mental health and burnout rates of healthcare professionals (HCPs) performing different roles.

AIMS

To examine mental health and burnout rates, and possible drivers for any disparities between professional roles.

METHODS

In this cohort study, online surveys were distributed to HCPs in July-September 2020 (baseline) and re-sent 4 months later (follow-up; December 2020) assessing for probable major depressive disorder (MDD), generalized anxiety disorder (GAD), insomnia, mental well-being and burnout (emotional exhaustion and depersonalization). Separate logistic regression models (at both phases) compared the risk of outcomes between roles: healthcare assistants (HCAs), nurses and midwives (nurses), allied health professionals (AHPs) and doctors (reference group). Separate linear regression models were also developed relating the change in scores to professional role.

RESULTS

At baseline (n = 1537), nurses had a 1.9-fold and 2.5-fold increased risk of MDD and insomnia, respectively. AHPs had a 1.7-fold and 1.4-fold increased risk of MDD and emotional exhaustion, respectively. At follow-up (n = 736), the disproportionate risk between doctors and others worsened: nurses and HCAs were at 3.7-fold and 3.6-fold increased risk of insomnia, respectively. Nurses also had a significantly increased risk of MDD, GAD, poor mental well-being and burnout. Nurses also had significantly worsened anxiety, mental well-being and burnout scores over time, relative to doctors.

CONCLUSIONS

Nurses and AHPs had excess risk of adverse mental health and burnout during the pandemic, and this difference worsened over time (in nurses especially). Our findings support adoption of targeted strategies accounting for different HCP roles.

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.

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.

THE ROLE OF EXERCISE IN PREVENTING CHRONIC DISEASES: CURRENT EVIDENCE AND RECOMMENDATIONS

Regular exercise helps to enhance health outcomes and lower risk factors, making it a crucial element in the prevention of chronic diseases. By being physically active, people can improve their general health and delay the onset of a number of chronic illnesses. For understanding the relationship between increased physical activity or decreased physical inactivity and favorable health outcomes, observational studies are the main source of information. We will look for systematic analyses of randomized controlled trials with a main emphasis on outcomes linked to diseases in the Cochrane Database of systematic studies. Evaluation will be limited to those in a few key chronic conditions. Preventing chronic illness and achieving better results in the management or treatment of chronic illness are the main outcomes of interest. For each chronic condition (such as the control of glucose in diabetes or any change in hypertension blood pressure), these results will be summarized and displayed. The design and implementation of chronic conditions, physical exercise illness conditions, and adverse physical activity-related events are of secondary interest. Our findings should help decision-makers, guideline organizations, and academics identify the most effective physical activity programs for major chronic disease management and prevention. Exercise and physical activity (PA) offers a non-invasive approach to the management of chronic disorders. More physiological, biochemical, and molecular data on the positive effects of PA and exercise on health should constitute a primary focus of future studies.

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.

Effect of laser bleaching, ultrasonic scaling and powered tooth brushing on surface roughness and bacterial adherence of class V composite restorations

Objective

To evaluate and compare the effect of diode laser assisted bleaching, ultrasonic scaling and powered tooth brushing on surface roughness and bacterial adherence on class V cavities restored with composites.

Materials and methods

A total of one hundred and twenty samples (40 samples each of Brilliant Everglow, Beautifil II and Heytec-N) were prepared in standardized stainless steel molds. The samples were further subdivided into four subgroups i.e. one control group (without any intervention) and three experimental groups - diode laser assisted bleaching, ultrasonic scaling and powered tooth brushing consisting of 10 sample each. Surface roughness was measured quantitatively with the help of 3D Optical Profilometer. For bacterial adherence analysis S. mutans strain (ATCC 25175) was cultured in BHI medium and samples were evaluated for the presence of viable bacteria using the Colony Forming Unit (CFU) count. Results obtained were then tabulated and subjected to statistical analysis.

Results

Diode laser bleaching caused a significant increase in surface roughness and bacterial adherence with lowest mean change exhibited by Heytec-N followed by Beautifil II and highest by Brilliant Everglow group. Similarly, Ultrasonic scaling increased the surface roughness of all the three tested samples with significant difference between the groups. Powered tooth brushing had no effect on the surface roughness and bacterial adherence of the tested composites.

Conclusion

Diode assisted laser bleaching and ultrasonic caused significantly higher surface roughness and bacterial adherence values for all the tested composites. It may therefore be recommended to do finishing and polishing of restorations after such procedures.

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.

Utilization of Waste Glass for Enhancement of Chemical Properties of Concrete

The world is facing a huge problem of waste generation; among these, solid waste in the form of glass has become a prime concern for the environment. The composition of the glass is silica-based, and its utilization in the preparation of concrete can be an efficient step in the direction of sustainable development by reducing the cement content. The formation of secondary calcium silicate hydrates (C-S-H) could take place due to the pozzolanic reaction of the fine ground glass with the cement. TGA techniques were used in this research to investigate the chemical properties of the waste glass, and later, these were compared with the properties of the cement. By keeping a constant w/b ratio for all the replacement levels from 0% to 35%, the evaluation of the workability and compressive strength were done. The evaluation showed that workability increased with an increase in the content of the waste glass. With 7 and 28 days cured samples, the strength and chemical investigation were conducted on the samples prepared with the same mix design. Constant Dose of superplasticizer used by weight of cement for mixes as 0.8%. Compared with the control sample, The level of replacement of waste glass to cement as 30% has depicted the augmentation in the compressive strength. Thus, the use of waste glass was found to be cost-effective and an environment-friendly solution for the sustainable development of concrete.

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.

Lateral diffusion of lipids in the DMPG membrane across the anomalous melting regime: effects of NaCl

The anionic dimyristoyl phosphatidylglycerol (DMPG) membrane in solvents with a low ionic strength is known to exhibit an unusually wide melting regime between the gel and fluid phase characterized by various anomalous macroscopic characteristics, such as low turbidity and high electrical conductivity and viscosity. A recent neutron spin echo study [Kelley, E. G. et al., Struct. Dyn., 7 (2020) 054704] revealed that during the extended melting phase transition the DMPG membrane becomes softer and exhibits faster collective bending fluctuation compared to the higher temperature fluid phase. In contrast, in the present work, using incoherent quasielastic neutron scattering through the anomalous phase transition regime we find that single-particle lateral and internal lipid motions in the DMPG membrane show regular temperature dependence, with no enhanced dynamics evident in the anomalous melting regime. Further, we find that incorporation of NaCl in DMPG suppresses the anomalous extended melting regime, concurrently enhancing the single-particle lipid dynamics, both the lateral diffusivity and (to a lesser extent) the internal lipid motion. This seems rather counterintuitive and in variance with the dynamic suppression effect exerted by a salt on a zwitterionic membrane. However, since incorporation of a salt in anionic DMPG leads to enhanced cooperativity, the disrupted cooperativity in the salt-free DMPG is associated with the baseline lipid dynamics that is suppressed to begin with, whereas addition of salt partially restores the cooperativity, thus enhancing lipid dynamics compared to the salt-free baseline DMPG membrane state. These results provide new insights into the ion-membrane interaction and divulge a correlation between microscopic dynamics and the structure of the lipid bilayer.

The Contribution of Transpiration to Precipitation Over African Watersheds

The redistribution of biological (transpiration) and non-biological (interception loss, soil evaporation) fluxes of terrestrial evaporation via atmospheric circulation and precipitation is an important Earth system process. In vegetated ecosystems, transpiration dominates terrestrial evaporation and is thought to be crucial for regional moisture recycling and ecosystem functioning. However, the spatial and temporal variability in the dependency of precipitation on transpiration remains understudied, particularly in sparsely sampled regions like Africa. Here, we investigate how biological and non-biological sources of evaporation in Africa contribute to rainfall over the major watersheds in the continent. Our study is based on simulated atmospheric moisture trajectories derived from the Lagrangian model FLEXPART, driven by 1° resolution reanalysis data over 1981-2016. Using daily satellite-based fractions of transpiration over terrestrial evaporation, we isolate the contribution of vegetation to monthly rainfall. Furthermore, we highlight two watersheds (Congo and Senegal) for which we explore intra- and interannual variability of different precipitation sources, and where we find contrasting patterns of vegetation-sourced precipitation within and between years. Overall, our results show that almost 50% of the annual rainfall in Africa originates from transpiration, although the variability between watersheds is large (5%-68%). We conclude that, considering the current and projected patterns of land use change in Africa, a better understanding of the implications for continental-scale water availability is needed.

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.

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.

Synthesis of Cu nanoparticle by Electro-Explosion of Wire (EEW) technique for immunosensing application.

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.

Participatory quantitative health impact assessment of urban transport planning: A case study from Eastern Africa

BACKGROUND

High rates of motorization in urban areas of Africa have adverse effects on public health. Transport-related mortality will increase as a result of inadequate transport infrastructure, air pollution and sedentary lifestyles. Health Impact Assessments (HIAs) have proven to be a successful tool to predict and mitigate negative health impact of urban transport planning policies, programmes or projects. Yet, there is a gap of evidence on transport and health in African countries. The aim of this study is assessing the health impacts of transport scenarios in Port Louis (city of 119,018 inhabitants in Mauritius) using a full chain participatory HIA model.

METHODS

We estimated health and economic impacts associated to transport scenarios with qualitative data and quantitative comparative risk assessment methods. The health impact modeling was based on differences between the baseline and three transport scenarios (worse, good, ideal), estimating the averted deaths per year and economic outcomes by assessing health determinants of air pollution (AP), traffic deaths and physical activity (PA). Data on air pollution and traffic fatalities were obtained from public data sources. Data used to construct scenarios, establish baseline travel mode shares and physical activity were collected through (a) open-ended individual interviews (IDIs) with 14 stakeholders (b) closed-ended survey questions to 600 citizens and (c) 2 focus group discussions (FGDs) with the same 14 stakeholders from (a).

RESULTS

In Port Louis, the worse-case transport scenario (doubling in car trips and a reduction in walking, motorcycle, and public transport), resulted in a total increment of 3.28 premature deaths per year. The good-case scenario (reducing car trips by half and increasing walking, motorcycle, and public transport trips) resulted in a total increment of 0.79 premature deaths per year. The ideal-case scenario (reduction in car and motorcycle trips and an increase in walking and public transport trips) resulted in a total reduction of 13.72 premature deaths per year. We estimated USD 23 millions of economic benefits related to mortality if the ideal-case was achieved.

CONCLUSION

Participatory HIA shows that implementing transport policies aiming for less than an ideal situation may not be adequate or sufficient to avoid negative transport-related mortality in Mauritius. Urban transport planning is an opportunity to encourage physical activity in rapidly urbanizing settings of Africa. Transport policies should aim to restrict all forms of private motorized vehicles and promote active and public transport to support public health. We highly recommend the use of participatory approaches in quantitative HIA to ensure context specificity and policy relevance.

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.

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.

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.

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

The systemic diagram shows the mechanism of photocatalysis, bacterial inhibition and photodynamic therapy through the generation of reactive oxygen species.

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.

What Factors Contribute to Intimate Partner Violence Against Women in Urban, Conflict-Affected Settings? Qualitative Findings from Abidjan, Côte d'Ivoire

Rapid urbanization is a key driver of the unique set of health risks facing urban populations. One of the most critical health hazards facing urban women is intimate partner violence (IPV). In post-conflict urban areas, women may face an even greater risk of IPV. Yet, few studies have examined the IPV experiences of urban-dwelling, conflict-affected women, including those who have been internally displaced. This study qualitatively examined the social and structural characteristics of the urban environment that contributed to the IPV experiences of women residing in post-conflict Abidjan, Côte d'Ivoire. Ten focus groups were conducted with men and women, both internally displaced (IDPs) and non-displaced. Lack of support networks, changing gender roles, and tensions between traditional gender norms and those of the "modern" city were reported as key contributors to IPV. Urban poverty and with it unemployment, food insecurity, and housing instability also played a role. Finally, IDPs faced heightened vulnerability to IPV as a result of displacement and discrimination. The relationship between economic strains and IPV are similar to other conflict-affected settings, but Abidjan's urban environment presented other unique characteristics contributing to IPV. Understanding these factors is crucial to designing appropriate services for women and for implementing IPV reduction interventions in urban areas. Strengthening formal and informal mechanisms for help-seeking, utilizing multi-modal interventions that address economic stress and challenge inequitable gender norms, as well as tailoring programs specifically for IDPs, are some considerations for IPV program planning focused on conflict-affected women in urban areas.

Computer aided morphometric analysis of oral leukoplakia and oral squamous cell carcinoma

We compared the changes in the cells in the basal layer of normal mucosa, oral leukoplakia with dysplasia and different grades of oral squamous cell carcinoma (OSCC) using computer aided image analysis of tissue sections. We investigated three morphometric parameters: nuclear area (NA), cell area (CA) and their ratio (NA:CA). NA and NA:CA ratio showed a statistically significant increase from dysplasia to increasing grades of OSCC. Nuclear size was useful for differentiating normal tissue, potentially malignant leukoplakia and OSCC.

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

Schematic representation of chemo and thermal therapy of folate conjugated magnetic nanoparticles (FA-MNPs) against cancer cells.

A descriptive study of tuberculosis case finding in private health care facilities in a South Indian district

SETTING

A South Indian district providing anti-tuberculosis services through the Revised National TB Control Programme (RNTCP) and private health care facilities.

OBJECTIVE

To ascertain the profile of tuberculosis (TB) patients diagnosed and/or treated in private health care facilities.

METHODS

Data on TB cases diagnosed and/or treated in all clinical departments of the medical college, 83 nursing homes and RNTCP health care facilities were collected prospectively.

RESULTS

About 83% of new TB cases recorded in the private medical college, 47% in nursing homes and 24.5% in RNTCP TB registers were extra-pulmonary. The proportion of retreatment cases was respectively 5.5%, 9.6% and 19.8%. The proportion of males and those in the economically productive age group were similar in the three data sources. About 94% of cases diagnosed in the medical college and 55% in nursing homes were registered for treatment under the RNTCP. About 11% of the smear-positive patients diagnosed in RNTCP were initial defaulters.

CONCLUSION

The proportion of extra-pulmonary cases was higher in the medical college and nursing homes and that of retreatment cases was lower than in the RNTCP.

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

Systemic diagram shows the cell death mechanism through the generation of reactive oxygen species.

Chitosan coated alginate micro particles for the oral delivery of antifilarial drugs and combinations for intervention in Brugia malayi induced lymphatic filariasis

Mechanism of targeting of MPs and absorption through Peyer’s patches, to lymphatics where an adult worm resides.

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

Schematic representation of in vitro cancer therapy using DOX loaded PEGylated FePt/Fe₃O₄ composite nanoassemblies (CNAs) in the presence of ACMF or H₂O₂.

Enhancement of magnetic heating efficiency in size controlled MFe2O4 (M = Mn, Fe, Co and Ni) nanoassemblies

The MFe₂O₄ magnetic nanoparticle nanoassemblies (MNNAs) have been synthesized via thermal decomposition of metal chloride in ethylene glycol (EG) in the presence of ethylenediamine (EDA).

Gender norms, poverty and armed conflict in Côte D'Ivoire: engaging men in women's social and economic empowerment programming

Engaging men is a critical component in efforts to reduce intimate partner violence (IPV). Little is known regarding men's perspectives of approaches that challenge inequitable gender norms, particularly in settings impacted by armed conflict. This article describes men's experiences with a women's empowerment program and highlights men's perceptions of gender norms, poverty and armed conflict, as they relate to achieving programmatic goals. Data are from 32 Ivorian men who participated in indepth interviews in 2012. Interviews were undertaken as part of an intervention that combined gender dialogue groups for both women and their male partners with women's only village savings and loans programs to reduce IPV against women. Findings suggested that in the context of armed conflict, traditional gender norms and economic stressors experienced by men challenged fulfillment of gender roles and threatened men's sense of masculinity. Men who participated in gender dialogue groups discussed their acceptance of programming and identified improvements in their relationships with their female partners. These men further discussed increased financial planning along with their partners, and attributed such increases to the intervention. Addressing men's perceptions of masculinity, poverty and armed conflict may be key components to reduce men's violence against women in conflict-affected settings.