Design and Synthesis of Peptide-Based Nanofibers for Imaging and Therapy of Cancer

Nanotechnology has been the subject of significant scientific and biomedical development efforts over the past decades. Improvement in biomarker discovery, targeting approaches and conjugation chemistries has led to the development of many novel nanomaterials for individualized therapy. In this thesis, we investigate a new class of nanomaterial called “nanofiber precursor” (NFP). The NFP is composed of multiple self-assembling peptides via electrostatic and non-covalent interactions. Each peptide consisted of β-sheet sequence attached to a methoxypolyethylene glycol (mPEG) via a linker. By conjugating either near infrared fluorophore or therapeutic antibodies, we demonstrate the application of NFP in diagnosis and therapy of cancer respectively. The main objectives of this thesis are: (1) To design and synthesize a near infrared nanofiber for imaging urokinase plasminogen activator (uPA) activity (2) To develop a Herceptin-conjugated nanofiber as multivalent targeted system for increasing therapeutic efficacy of Herceptin, a monoclonal antibody used for breast cancer treatment. We were successful in conjugating near infrared dye NIR664 to the nanofiber as well as Herceptin on the surface of nanofiber. (1) The NIR-NFP conjugate could detect recombinant uPA activity with sensitivity of 3 ng. (2) The Herceptin-conjugated nanofiber (HER-NFP) was more than two fold effective in inhibiting growth of HER-2 positive cells. In the second half of the thesis, we have also investigated tumorigenic role of 15-LOX-1, a lipid peroxidizing enzyme in prostate cancer. The aim of this study was: (3) To investigate the role of 15-lipoxygenase-1 (15-LOX-1) in upregulation of uPA in PC-3 prostate cancer cells. As a whole, the research presented in this thesis is aimed at designing new strategies and understanding molecular mechanisms that lead to prevention and treatment of cancer

Green Synthesis of Silver Nanoparticles using Aqueous Cranberry Fruit Extract and its Antibacterial Activity

Objective: Cranberry (Vaccinium macrocarpon) is popularly used in traditional folk medicine for treatment of microbial infections. The aim of the present study was to evaluate the antibacterial activity of aqueous cranberry fruit extract (ACE) against pathogenic cultures and its application in green synthesis of silver nanoparticles. Methods: ACE was screened for its antibacterial activity by agar well diffusion assay. The minimum inhibitory concentration (MIC) was determined by broth macrodilution technique, and minimum bactericidal concentration (MBC) was quantified. ACE was used in the green synthesis of silver nanoparticles (AgNPs), which were characterized by an Ultraviolet–visible (UV-VIS) spectroscopy and Field emission gun-scanning electron microscopy (FEG-SEM) techniques. Agar well diffusion assay was used to evaluate the antibacterial activity of the AgNPs formed. Results: The zone of inhibition (ZOI) for ACE was found to be in the range of 19 - 30.3 mm, for the concentration of 100% (v/v). The MIC values were in the range of 12.5% - 50% (v/v) and the values indicated that a concentration of 50% (v/v) ACE could inhibit 87.5% (7/8) test cultures. The formation of AgNPs was confirmed by UV-VIS spectroscopy and the surface-plasmon resonance peak was observed at 430 nm. The FEG-SEM analysis revealed that the most of AgNPs were spherical in shape and had 15-25 nm size range. All the test cultures were inhibited by the AgNPs and the average ZOI measured 25.7±5.6 mm. Conclusion: Cranberry fruit extract has a potent antibacterial activity against pathogens and it can be applied in green synthesis of silver nanoparticles. Keywords: Cranberry, MIC, MBC, silver nanoparticles, FEG-SEM

N-[4-(2-Morpholino­eth­oxy)phen­yl]acetamide monohydrate

In the title compound, C14H20N2O3·H2O, the geometry about the morpholine N atom implies sp 3 hybridization. In the crystal, symmetry-related mol­ecules are linked by inter­molecular N—H⋯O, O—H⋯O and O—H⋯N hydrogen bonds, forming infinite chains along the b axis. The chain structure is further stabilized by intra­molecular C—H⋯O inter­actions

Study of Antibacterial activity of Phyllanthus emblica and its role in Green Synthesis of Silver Nanoparticles

Objective: Phyllanthus emblica L. or amla is known for its therapeutic properties. The aim of the present study was to evaluate the antibacterial activity of aqueous Phyllanthus emblica fruit extract (APE) against eight pathogenic cultures and its application in green synthesis of silver nanoparticles. Methods: APE was screened for the presence of phytochemicals and its antibacterial activity was evaluated by agar well diffusion assay. The minimum inhibitory concentration (MIC) was quantified by broth macrodilution technique, and minimum bactericidal concentration (MBC) was determined. Further, APE was used in the biological synthesis of silver nanoparticles (AgNPs), which were characterized by an Ultraviolet–visible (UV-VIS) spectroscopy and Field emission gun-scanning electron microscopy (FEG-SEM) techniques. The antibacterial activity of the AgNPs was screened by agar well diffusion assay. Results: The zone of inhibition (ZOI) for APE was found to be in the range of 10.7–21.3 mm, for varying concentrations. The MIC values were in the range of 12.5% - 50% (v/v) and the MBC values indicated that a concentration of 50% (v/v) APE could kill 75% (6/8) test cultures. The presence of AgNPs was confirmed by UV-VIS spectroscopy and the surface-plasmon resonance peak was observed at 420 nm. The FEG-SEM analysis revealed that the most of AgNPs were spherical in shape and had 30-40 nm size range. All the test cultures were inhibited by the AgNPs and the average ZOI measured 19.25±2.7 mm. Conclusion: Phyllanthus emblica fruit extract might have therapeutic significance against pathogens and it can be used for green synthesis of silver nanoparticles. Keywords: Phyllanthus emblica, MIC, MBC, silver nanoparticles, UV-VIS, FEG-SEM

Feasibility and Complications between Phacoemulsification and Manual Small Incision Surgery in Subluxated Cataract

Purpose. To compare the feasibility of cataract surgery with implantation of endocapsular supporting devices and intraocular lens (IOL) in subluxated cataract in phacoemulsification and manual small incision cataract surgery (MSICS). Design. Prospective randomized intervention case series consisting of 60 eyes with visually significant subluxated cataract. Method. The patients were randomly distributed between the two groups equally. The main outcome measure was implantation of in-the-bag IOL, requirement of additional procedure and complications, if any. Results. Capsular bag retention in subluxated lenses is possible in 90% cases in phacoemulsification versus 76.67% cases in MSICS (=0.16). Both groups, achieved similar best corrected visual acuity (=0.73), although additional procedures, intraoperative, and postoperative complications were more common in MSICS. Conclusions. Achieving intact capsulorhexis and nuclear rotation in MSICS may be difficult in cases with large nucleus size and severe subluxation, but subluxated cataracts can be effectively managed by both phacoemuslification and MSICS

Human Chorionic Gonadotropin Influences Systemic Autoimmune Responses

Immunopathological outcomes in Systemic Lupus Erythematosus (SLE; or lupus) are believed to be autoantibody-mediated. Conditions which promote a Th2 skew (such as pregnancy) should encourage antibody production, worsening antibody-mediated diseases while ameliorating Th1/Th17-mediated diseases. Although an increased propensity toward autoreactivity can be observed in pregnant lupus patients and in pregnant lupus-prone mice, whether a unique human pregnancy-specific factor can contribute to such effects is unknown. This study assessed whether human chorionic gonadotropin (hCG, a pregnancy-specific hormone of diverse function) at physiological concentrations could mediate stimulatory influences on immune parameters in non-pregnant, lupus-prone mice, in light of the hormone's ameliorating effects on Th1-mediated autoimmunity in murine models. Results demonstrate that administration of hCG heightened global autoreactivity in such mice; antibodies to dsDNA, RNP68, Protein S, Protein C, β2-glycoprotein 1, and several phospholipids were enhanced, and hormone administration had adverse effects on animal survival. Specifically in splenic cell cultures containing cells derived from lupus-prone mice, hCG demonstrated synergistic effects with TLR ligands (up-modulation of costimulatory markers on B cells) as well as with TCR stimuli (enhanced proliferative responses, enhanced levels of cytokines, and the phosphorylation of p38). In both instances, enhanced synthesis of lupus-associated cytokines was observed, in addition to the heightened generation of autoantibodies reactive toward apoptotic blebs. These results suggest that selective transducive, proliferative, and differentiative effects of hCG on adaptive immune cells may drive autoreactive responses in a lupus environment, and may also potentially provide insights into the association between the presence of higher hCG levels (or the administration of hCG) with the presence (or appearance) of humoral autoimmunity

Prefrontal Interneurons: Populations, Pathways, and Plasticity Supporting Typical and Disordered Cognition in Rodent Models

Prefrontal cortex (PFC) inhibitory microcircuits regulate the gain and timing of pyramidal neuron firing, coordinate neural ensemble interactions, and gate local and long-range neural communication to support adaptive cognition and contextually tuned behavior. Accordingly, perturbations of PFC inhibitory microcircuits are thought to underlie dysregulated cognition and behavior in numerous psychiatric diseases and relevant animal models. This review, based on a Mini-Symposium presented at the 2022 Society for Neuroscience Meeting, highlights recent studies providing novel insights into: (1) discrete medial PFC (mPFC) interneuron populations in the mouse brain; (2) mPFC interneuron connections with, and regulation of, long-range mPFC afferents; and (3) circuit-specific plasticity of mPFC interneurons. The contributions of such populations, pathways, and plasticity to rodent cognition are discussed in the context of stress, reward, motivational conflict, and genetic mutations relevant to psychiatric disease

Ebola virus - Epidemiology, Diagnosis, and Control: Threat to Humans, Lessons Learnt, and Preparedness Plans - an Update on Its 40 Year\u27s Journey

Ebola virus (EBOV) is an extremely contagious pathogen and causes lethal hemorrhagic fever disease in man and animals. The recently occurred Ebola virus disease (EVD) outbreaks in the West African countries have categorized it as an international health concern. For the virus maintenance and transmission, the non-human primates and reservoir hosts like fruit bats have played a vital role. For curbing the disease timely, we need effective therapeutics/prophylactics, however, in the absence of any approved vaccine, timely diagnosis and monitoring of EBOV remains of utmost importance. The technologically advanced vaccines like a viral-vectored vaccine, DNA vaccine and virus-like particles are underway for testing against EBOV. In the absence of any effective control measure, the adaptation of high standards of biosecurity measures, strict sanitary and hygienic practices, strengthening of surveillance and monitoring systems, imposing appropriate quarantine checks and vigilance on trade, transport, and movement of visitors from EVD endemic countries remains the answer of choice for tackling the EBOV spread. Herein, we converse with the current scenario of EBOV giving due emphasis on animal and veterinary perspectives along with advances in diagnosis and control strategies to be adopted, lessons learned from the recent outbreaks and the global preparedness plans. To retrieve the evolutionary information, we have analyzed a total of 56 genome sequences of various EBOV species submitted between 1976 and 2016 in public databases

Advances in Developing Therapies to Combat Zika Virus: Current Knowledge and Future Perspectives

Zika virus (ZIKV) remained largely quiescent for nearly six decades after its first appearance in 1947. ZIKV reappeared after 2007, resulting in a declaration of an international “public health emergency” in 2016 by the World Health Organization (WHO). Until this time, ZIKV was considered to induce only mild illness, but it has now been established as the cause of severe clinical manifestations, including fetal anomalies, neurological problems, and autoimmune disorders. Infection during pregnancy can cause congenital brain abnormalities, including microcephaly and neurological degeneration, and in other cases, Guillain-Barré syndrome, making infections with ZIKV a substantial public health concern. Genomic and molecular investigations are underway to investigate ZIKV pathology and its recent enhanced pathogenicity, as well as to design safe and potent vaccines, drugs, and therapeutics. This review describes progress in the design and development of various anti-ZIKV therapeutics, including drugs targeting virus entry into cells and the helicase protein, nucleosides, inhibitors of NS3 protein, small molecules, methyltransferase inhibitors, interferons, repurposed drugs, drugs designed with the aid of computers, neutralizing antibodies, convalescent serum, antibodies that limit antibody-dependent enhancement, and herbal medicines. Additionally, covalent inhibitors of viral protein expression and anti-Toll-like receptor molecules are discussed. To counter ZIKV-associated disease, we need to make rapid progress in developing novel therapies that work effectually to inhibit ZIKV