Optically active organic and inorganic nanomaterials for biological imaging applications: A review.

Recent advancements in the field of nanotechnology have enabled targeted delivery of drug agents in vivo with minimal side effects. The use of nanoparticles for bio-imaging has revolutionized the field of nanomedicine by enabling non-invasive targeting and selective delivery of active drug moieties in vivo. Various inorganic nanomaterials like mesoporous silica nanoparticles, gold nanoparticles, magnetite nanoparticles graphene-based nanomaterials etc., have been created for multimodal therapies with varied multi-imaging modalities. These nanomaterials enable us to overcome the disadvantages of conventional imaging contrast agents (organic dyes) such as lack of stability in vitro and in vivo, high reactivity, low-quantum yield and poor photo stability. Inorganic nanomaterials can be easily fabricated, functionalised and modified as per requirements. Recently, advancements in synthesis techniques, such as the ability to generate molecules and construct supramolecular structures for specific functionalities, have boosted the usage of engineered nanomaterials. Their intrinsic physicochemical properties are unique and they possess excellent biocompatibility. Inorganic nanomaterial research has developed as the most actively booming research fields in biotechnology and biomedicine. Inorganic nanomaterials like gold nanoparticles, magnetic nanoparticles, mesoporous silica nanoparticles, graphene-based nanomaterials and quantum dots have shown excellent use in bioimaging, targeted drug delivery and cancer therapies. Biocompatibility of nanomaterials is an important aspect for the evolution of nanomaterials in the bench to bedside transition. The conduction of thorough and meticulous study for safety and efficacy in well-designed clinical trials is absolutely necessary to determine the functional and structural relationship between the engineered nanomaterial and its toxicity. In this article an attempt is made to throw some light on the current scenario and developments made in the field of nanomaterials in bioimaging.

The impact of engineered nanomaterials on the environment: Release mechanism, toxicity, transformation, and remediation.

The presence and longevity of nanomaterials in the ecosystem, as well as their properties, account for environmental toxicity. When nanomaterials in terrestrial and aquatic systems are exposed to the prevailing environmental conditions, they undergo various transformations such as dissociation, dissolution, and aggregation, which affects the food chain. The toxicity of nanomaterials is influenced by a variety of factors, including environmental factors and its physico-chemical characteristics. Bioaccumulation, biotransformation, and biomagnification are the mechanisms that have been identified for determining the fate of nanomaterials. The route taken by nanomaterials to reach living cells provides us with information about their toxicity profile. This review discusses the recent advances in the transport, transformation, and fate of nanomaterials after they are released into the environment. The review also discusses how nanoparticles affect lower trophic organisms through direct contact, the impact of nanoparticles on higher trophic organisms, and the possible options for remediation.

Effect of Withania Somnifera on the antioxidant and neurotransmitter status in sleep deprivation induced Wistar rats.

Sleep is normally a period of relaxation and repair, important for the maintenance of physiological homeostasis and psychological balance. "Globally, millions of people experiences sleep deprivation daily". Sleep deprivation (SD) impairs cognitive functions, decreases anti-oxidative defense and induces neuronal changes. Withania somnifera (WS), commonly known as an "Indian Ginseng" has broad therapeutic applications, including anti-inflammatory activities, actions on immune system, circulatory system, central nervous system etc., The study is aimed to assess effect of Withania somnifera on antioxidant status and neurotransmitter level in sleep deprivation induced male Wistar albino rats. The study was done in the Department of Physiology, Meenakshi Medical College and Hospital, Enathur, Kanchipuram. 24 male adult Wistar rats weighing 120-150g were used for the study. They were divided into 4 groups with 6 animals in each group. (Group I - cage control, Group II - large platform control, Group III - sleep deprived group and Group IV - WS treated SD group). Animals were deprived sleep for one week using a modified multiple platform method. Oxidative stress parameters and antioxidant enzymes were measured using spectrophotometry. Neurotransmitters such as dopamine and serotonin concentration in the serum were measured by ELISA method. There was a marked (by one-way ANOVA test) decrease observed in the antioxidants enzymes in the cortex of both large platform control and sleep deprivation induced group. The group treated with W. somnifera root extract significantly reduced the free radical production and lipid peroxidation with simultaneous increase in the level of antioxidant enzymes compared to the untreated group. Also in our study the concentration of dopamine and serotonin was found to be significantly reduced (p < 0.05) in sleep deprived (SD) and large platform control group when compared to cage control group. Whereas the group treated with W. somnifera (400mg/kg b.wt) increased the neurotransmitter levels significantly. Withania somnifera proved to be an effective therapeutic agent by maintaining the antioxidant status and neurotransmitter levels.

In vitro anti-diabetic assessment of guavanoic acid functionalized gold nanoparticles in regulating glucose transport using L6 rat skeletal muscle cells.

Guavanoic acid functionalized gold nanoparticles exhibit anti-diabetic potential by improving insulin dependent glucose uptake in L6 rat skeletal muscle cells. The mode of action of the gold nanoparticles was established from the glucose uptake assay in the presence and absence of genistein and wortmannin. The anti-diabetic efficacy of guavanoic acid functionalized gold nanoparticles was put forth by in vitro assays like for PTP 1B, α-amylase and α-glucosidase enzyme activities. Studies on cytotoxicity revealed 50% inhibition of cells at 265 ± 0.01 µg mL-1. In the LDH enzyme release assay on differentiated L6 myoblasts treated with different concentrations (1-100 µg mL-1) of guavanoic acid functionalized gold nanoparticles, a viability of 75% at 100 µg mL-1 was observed.

Regulation of pro and anti-inflammatory signaling molecules in effect of Withania Somnifera root extract treated sleep deprivation induced Wistar rats.

Sleep plays an imperative role in maintaining good health. Sleep along with circadian cycle wields strong regulatory control over immunity. Sleep deprivation (SD) is a threat to health developing several immunological disorders. The medicinal plant Withania somnifera (WS) root extract is widely used for its immuno-modulatory properties. Therefore, it is of interest to assess the effect of WS root extract on pro and anti-inflammatory signalling in SD rats. 24 male Wistar rats (120-150g) were divided into 4 groups with 6 animals in each. The groups were divided such that Group I - cage control, Group II - large platform control, Group III - sleep deprived & Group IV - WS treated SD rats. RT-PCR based mRNA expression analysis of pro inflammatory (IL-1ß, IL-6, MCP-1, TNF-α) and anti-inflammatory marker (IL-10) in the cortex of control and SD rats were completed. Concurrent protein expression analysis was completed using western blot. Data was analyzed using one-way ANOVA and Duncan's multiple range test in SPSS software version 20. Data showed elevation of pro-inflammatory markers and depression of IL-10. Thus, WS down regulated the pro-inflammatory and up-regulated the anti-inflammatory molecules, which can be further considered towards the treatment of sleep deprivation induced inflammatory diseases.

Protection of mice against gastric colonization of Helicobacter pylori by therapeutic immunization with systemic whole cell inactivated vaccines.

The protective effect of therapeutic immunization with heat inactivated Helicobacter pylori cells administered with aluminum phosphate as an adjuvant was evaluated with "Swiss albino mice" infected with H. pylori Sydney strain 1 (SS1). The presence of bacteria in histological sections of the stomach was evaluated to confirm the colonization of H. pylori. The infection dose was determined to be 1 × 108 cells which resulted to be the optimal concentration to sustain infection for required time. Systemic immunization of H. pylori 26695 and SS1 Whole cell heat inactivated vaccine were induced on mice. The IgG titer levels of high dose adjuvant vaccine of both strains were proportionate on the 7th and 14th day. Subsequently on the 21st and 28th day SS1 high dose adjuvant revealed a higher titer value. The Probability values were <0.0001 which is statistically significant. Moreover, therapeutic immunization with SS1 (WC) vaccine confers efficacious protection against H. pylori infection in mice. These results represent strong evidence for feasibility of therapeutic use of whole cell based vaccine formulations against H. pylori infection in animal model.

Pectin mediated gold nanoparticles induces apoptosis in mammary adenocarcinoma cell lines.

Pectin and its several modified forms have shown remarkable impact in therapeutic use against various cancers. In the present study, pectin, an anionic polysaccharide isolated from Musa paradisiaca is employed for the synthesis of gold nanoparticles at ambient temperature conditions. The synthesized nanoparticles were characterized using microscopic and spectroscopic studies and its anti-cancer potential was evaluated in mammary adenocarcinoma cell lines MCF-7 and MDA-MB-231. Apoptosis induction was evident from increase in sub-G1 population studied using flow cytometry analysis. DNA damage followed by cell death in pectin mediated gold nanoparticles (p-GNPs) treated cells was confirmed by Comet assay. Uptake of p-GNPs by cancer cells (MCF-7 and MDA-MB-231) was analyzed using FE-SEM which revealed the presence of p-GNPs as aggregates over the surface of cells with loss in cellular integrity compared to control cells.

Conjunctival Autograft Versus Amniotic Membrane Transplantation After Double Pterygium Excision: A Randomized Trial.

PURPOSE: To compare the outcome of amniotic membrane transplantation (AMT) and conjunctival autograft (CAG) after pterygium excision in patients with nasal and temporal pterygium (double pterygium) in the same eye. METHODS: Tertiary care medical center. A total of 33 eyes of 33 patients with previously unoperated double pterygium were enrolled in the randomized trial, of which 31 remained in follow-up at 1 year. Eyes with double pterygium were randomized to either nasal AMT and temporal CAG (nasal AMT group) or to temporal AMT and nasal CAG (temporal AMT group). The primary prespecified outcome was pterygium recurrence at the excised site 1 year after pterygium excision. RESULTS: At 1 year none of the 31 pterygia randomized to CAG showed recurrence in either the nasal or temporal location (0%, 95% confidence interval, 0%-11.2%). In contrast, 8 of 31 pterygia randomized to AMT exhibited recurrence at 1 year (25.8%, 95% confidence interval, 11.9%-44.6%), with 4 temporal recurrences and 4 nasal recurrences. The recurrence rate was significantly higher for AMT than CAG (P = 0.005: primary analysis), but not significantly different between the nasal and temporal sites (P ≥ 0.99). CONCLUSIONS: The use of CAG in pterygium surgery led to fewer recurrences than AMT, irrespective of the site of replacement.

Size controlled biogenic silver nanoparticles as antibacterial agent against isolates from HIV infected patients.

Silver nanoparticles (AgNPs) are synthesized using biological sources due to its high specificity in biomedical applications. Herein, we report the size and shape controlled synthesis of AgNPs using the aqueous extract of blue green alga, Spirulina platensis. Size, shape and elemental composition of AgNPs were characterized using UV-vis spectroscopy, Fluorescence spectroscopy, FT-IR (Fourier Transform-Infrared Spectroscopy), FT-RS (Fourier Transform-Raman Spectroscopy), SEM-EDAX (Scanning Electron Microscopy-Energy Dispersive X-ray analysis) and HR-TEM (High Resolution Transmission Electron Microscopy). AgNPs were stable, well defined and monodispersed (spherical) with an average size of 6 nm. The synthesized AgNPs were tested for its antibacterial potency against isolates obtained from HIV patients.

Blue green alga mediated synthesis of gold nanoparticles and its antibacterial efficacy against Gram positive organisms.

Biofunctionalized gold nanoparticles (AuNPs) play an important role in design and development of nanomedicine. Synthesis of AuNPs from biogenic materials is environmentally benign and possesses high bacterial inhibition and bactericidal properties. In the present study, blue green alga Spirulina platensis protein mediated synthesis of AuNPs and its antibacterial activity against Gram positive bacteria is discussed. AuNPs were characterized using Ultraviolet-visible (UV-vis) spectroscopy, Fluorescence spectroscopy, Fourier Transform-Infrared (FTIR) spectroscopy, Raman spectroscopy, High Resolution-Transmission Electron Microscopy (HR-TEM) and Energy Dispersive X-ray analysis (EDAX). Stable, well defined AuNPs of smaller and uniform shape with an average size of ~ 5 nm were obtained. The antibacterial efficacy of protein functionalized AuNPs were tested against Gram positive organisms Bacillus subtilis and Staphylococcus aureus.

Diagnostic issues in a case of hodgkin lymphoma with castleman like features.

Castleman disease (CD) is a benign heterogenous lymphoproliferative disorder presenting with varied clinical manifestations. Histomorphologically, two distinct variants are known, hyaline vascular type and plasma cell type. CD is reported to be associated with lymphomas. Though Non Hodgkin lymphoma is more commonly associated with CD, its association with Hodgkin lymphoma (HL) is also well known and documented. Many a times, CD obscures or masks the underlying lymphomas thus delaying the diagnosis. There are also reports of HL showing Castleman like features. We report a case of HL with Castleman like features which posed diagnostic difficulty owing to the fragmented nature and tiny size of the initial lymph node biopsy. Striking peripheral blood rouleaux formation which was seen in our case along with bone marrow plasmacytosis has not been described in the previously diagnosed cases.

Synthesis and functional characterization of antibiofilm exopolysaccharide produced by Enterococcus faecium MC13 isolated from the gut of fish.

The synthesis and functional characterization of an antibiofilm exopolysaccharide (EPS) from a probiotic Enterococcus faecium MC13 were investigated. The temperature of 35 °C, pH of 6.5, and salinity of 1-2% were found to be optimum for EPS production. The sucrose (30 g l⁻¹) and yeast extract (20 g l⁻¹) acted as suitable carbon and nitrogen sources, respectively, which strongly influenced EPS production with yield of 11.33 and 11.91 g l⁻¹. Based on the thin layer chromatography, EPS of E. faecium MC13 was found to be a heteropolysaccharide, composed of galactose and glucose sugar units with a molecular mass of 2.0 × 105 Da. Fourier transform infrared spectrum analysis of the EPS revealed many predominant functional groups including hydroxyl, carboxyl, and amide groups. EPS exhibited better emulsifying and flocculating activities which is relatively similar to those of commercial polysaccharides. In vitro antioxidant inspect of EPS showed lesser antioxidant activity than that of the control ascorbic acid. Thermal behavior of EPS was different from the other EPS produced by other lactic acid bacteria. In vitro antibiofilm assay of EPS exhibited significant biofilm inhibition, especially with Listeria monocytogenes. To the best of our knowledge, this is the first report on EPS of E. faecium with strong emulsifying and flocculating activities.