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Design, Development and Evaluation of Dual Drug Nanomedicine for Non-Small Cell Lung Cancer
Get PDFResistance to conventional chemotherapy is a big challenge in the treatment of cancer including non-small cell lung cancer (NSCLC). A combination of natural chemo sensitizer agents with chemotherapy offers unique advantages over monotherapy alone. However, free unbound drugs, (in combination or as a single agent), lack tumor-targeted accumulation and therefore can be easily eliminated from the patient body. Moreover, some drugs are hydrophobic, and their organic solvents cause in vivo toxicity, thereby limiting their capability in clinical translation. Herein, dual loaded biocompatible and biodegradable nanoparticles (NPs) using Gemcitabine (Gem)a pyrimidine nucleoside antimetabolite and Gambogic acid (GA) (a highly hydrophobic chemo sensitizer agent)- were developed on human serum albumin-tannic acid nano-platform (HTA) for targeted treatment of NSCLC.Our in vitro results demonstrate that Gem and GA combination therapy has tremendous potential due to their high efficacy on NSCLC, and GA sensitize NSCLC to Gem therapy. However, GA used in combination with Gem suffers from limited solubility which subsequently leads to a decline in therapeutic efficacy. Therefore, in order to overcome this, in the present study GA and Gem were encapsulated in human serum albumin-tannic acid nanoparticles by the solvent evaporation method. In this platform, HTA is a biocompatible nanocarrier that binds to both GA and Gem. Physico chemical characterizations studies revealed that GA and Gem are successfully encapsulated in HTA NPs with uniform spherical morphology. These nanoparticles were readily taken up by NSCLC cells (A549 and H1299) in a concentration and time-dependent manner. Apart from an increase in GA solubility, encapsulated GA and Gem subsequently manifested elevated therapeutic efficacy, which was confirmed by cell viability, colony formation, migration and invasion studies. Furthermore, in vivo and ex vivo imaging analysis demonstrated notable tumor-targeting behavior of our uniquely designed HTA NPs in mice bearing A549 xenograft tumors. These findings clearly illustrate that our dual loaded NPs can be efficiently utilized to improve cancer therapy and tumor eradication
Forecasting the Essential Chemotherapy Needed for Treatment of Children with Acute Lymphoblastic Leukemia in Low- and Middle-Income Countries
Get PDFAcute lymphoblastic leukemia (ALL) is the most common pediatric cancer, with contemporary therapy resulting in a 90% survival in high-income countries (HIC). However, an estimated 89% of the world’s children live in low- and middle-income countries (LMIC) where survival is much lower. Lack of access to essential chemotherapy contributes significantly to the decreased survival rates for LMIC, and inaccurate forecasting of chemotherapy needed may lead to stockouts or oversupply. This chapter describes a simple forecasting system with population and patient-based multipliers for each drug used in the treatment of pediatric ALL, thus estimating the essential chemotherapy quantities needed for a single patient, facility, region, or country.
We described a forecasting model for estimating essential chemotherapy in the treatment of childhood ALL to multipliers. Multipliers were obtained from a reference population of 10 million children evenly distributed (2.5 million each) across four age cohorts at 5-year intervals (0-4, 5-9, 10-14, and 15-19 years). The forecasting model and multipliers were applied to 171 countries with age-specific population data available in the United Nations 2017 World Populations Prospects. Results from the forecasting model and multipliers were compared to determine differences for each country and for countries with extreme population distributions across the pediatric age range. The multipliers produced results no greater than 15% of those obtained using the forecasting model.
Multipliers allow healthcare providers, cancer centers, hospitals, countries, and drug manufacturers to accurately estimate the essential chemotherapy needs for a patient, facility, region, or country. This practical tool can be applied to other cancer diagnoses and treatment protocols
Biochemical and Structural Characterization of the Atg8/LC3 Lipidation Pathway
Get PDFAtg8 and its eukaryotic orthologues LC3 and GARBARAP family proteins (referred here to Atg8 family proteins) play crucial roles in autophagy through their covalent ligation to lipids, typically phosphatidylethanolamine (PE), in a process known as lipidation. Lipidation of Atg8 family proteins regulates numerous facets of the autophagy process, including regulating expansion of the phagophore membrane, recruiting selected cargoes for degradation, and providing an autophagosome membrane-bound platform mediating dynamic interactions with other regulatory proteins. Atg8 family proteins are ubiquitin-like proteins (UBLs), and their lipidation involves a divergent UBL conjugation cascade including Atg7, Atg3, and Atg12–Atg5-Atg16 acting as E1, E2, and E3 enzymes, respectively. Atg7 initiates Atg8 conjugation by catalyzing their C-terminal adenylation and conjugation to the catalytic cysteine of Atg3. Ultimately, the Atg12–Atg5-Atg16 complex catalyzes Atg8 ligation to a primary amino group on PE or other acceptor lipids. Molecular mechanisms underlying Atg8 lipidation remain poorly understood despite association of Atg3, the E1 Atg7, and the composite E3 Atg12–Atg5-Atg16 with pathologies including cancers, infections, and neurodegeneration. The first part of this dissertation work describes methods for expressing and purifying human LC3 or GABARAP, ATG7, ATG3, and the ATG12–ATG5-ATG16L1 complex for in vitro studies of LC3/GABARAP lipidation; based on these protocol established, we report that an Atg3 element we term E123IR (E1, E2, and E3-interacting region) is an allosteric switch, by studying yeast enzymes. Nuclear magnetic resonance (NMR), biochemical, crystallographic and genetic data collectively indicate that in the absence of the enzymatic cascade, the Atg3E123IR makes intramolecular interactions restraining Atg3’s catalytic loop, while E1 and E3 enzymes directly remove this brace to conformationally activate Atg3 and elicit Atg8 lipidation in vitro and in vivo. We propose that Atg3’s E123IR protects the E2~UBL thioester bond from wayward reactivity toward errant nucleophiles, while Atg8 lipidation casca
Effectiveness of Splinting in Adults with Radial Nerve Palsy
Get PDFThe final portfolio contains 5 research articles from national and international journals. The study designs included in this portfolio are one small-scale RTC, one retrospective pretest posttest design, and three case studies. The studies included help answer our PICO question and help draw conclusions about how to care for adults with radial nerve palsy in regards to splinting. Three of the articles compared static splinting and dynamic splinting in regards to improvements in hand function. Two of the articles focused on dynamic splinting as a means of treatment for adults with radial nerve palsy
Blend to Bend: Exploring Blended Learning Concepts in the Age of Pandemic
Get PDFObjective: This poster is designed to be a narrative review presenting information focused on blended learning as a possible option for health science library instruction modification during COVID-19. Concepts including definitions of blended learning, impacts, benefits, challenges, and considerations when transitioning will be explored.
Methods: A literature review was conducted using the following databases: ERIC, EBSCO Education Source, ProQuest Education Database, Web of Science; along with other resources including Google Scholar, LibTechEd, and Blended Online Learning & Distance Education (BOLDE). Search terms included “blended learning,” “hybrid learning,” “flipped classroom,” and “blended instruction.”
Results: Results were narrowed to articles focused on transitioning from a predominantly traditional face-to-face modality to blended learning and articles focused on blended learning in the library environment.
Conclusions: Blended learning may provide an opportunity to continue library instruction while still following public health and safety guidelines during the COVID-19 pandemic
Audiovisual Integration During Novel Word Learning Among School-Aged Children with Cochlear Implants
Get PDFObjective. It is well established that being able to see someone’s mouth move as they speak boosts speech perception for children with cochlear implants (CIs). Thus, children with CIs are often instructed to orient themselves toward the person they are listening to, to gain access to visual speech cues. Children with CIs who are better “audiovisual integrators,” or those who experience an auditory-visual (AV) enhancement effect (higher performance for AV information than auditory-alone (AO) or visual-alone (VO)), are more likely to have better speech and language outcomes after receiving their CI than children with poorer AV integration skills. While AV integration of speech appears to be intimately tied with speech perception as well as speech and language development, its role in vocabulary acquisition is not well understood. This study examined novel word learning across two tasks, AV and AO, and sought to answer the following questions: (1) How does access to AV information impact novel word learning success for children with CIs and children with normal hearing (NH) listening to normal and CI-simulated speech? (2) How do individual patterns of visual attention during learning relate to individual word learning outcomes? (3) What measured factors (hearing history, device characteristics, maternal education level, etc.) contribute to novel word learning across AV and AO tasks? Methods. Twelve children with CIs (M = 7 years; 9 months) and twenty-four age- and sex-matched children with NH (M = 7 years; 8.6 months) completed two novel word learning tasks, AV and AO. Across both tasks, a female speaker was positioned on the top half of the screen and narrated a story. The corresponding story page and object to-be-learned was displayed on the bottom half of the screen. During the AO task, a black box was positioned over the speaker’s face to block access to visual speech cues. Twelve object-label pairs were presented across three blocks and word learning was assessed with a four-alternative forced-choice (4AFC) task following each block of presentations.
Results. Across listener groups, children did not learn significantly more words in the AV task as compared to the AO task. Within the group of children with CIs, two subgroups of performers were noted, “higher” and “poorer” word learners. Individual visual attention patterns corresponded with individual word learning outcomes for children who use CIs in these two performance groups. Children with CIs who spent more time looking at the speaker’s mouth learned more words than children who spent less time attending to the speaker’s mouth. Additionally, earlier age of amplification was significantly correlated with better learning outcomes. Many subscales across the LEAF, a parental report of executive functioning skills, were significantly correlated with word learning in the AO and AV tasks. Outcomes on the TONI-4, a nonverbal intelligence measure, and the Blending subtest of the CTOPP-2, an assessment of phonological processing, were also correlated with learning outcomes.
Conclusions. This study found no significant main effect of task type, which suggests that encouraging children with CIs to orient themselves to the speaker they are attending to may not be sufficient to support or improve vocabulary acquisition, particularly for children who demonstrate difficulty acquiring new words. Age of amplification, age of implantation, and phonological processing skills differentiated the two performance groups. Group differences also emerged where poorer and better CI performers showed differences in their visual attention to the task. These outcomes indicate that early learning and development of strategies for word learning warrants further investigation
Role of Cerebral Vasculature and Effect of Circulating Exosomes in Propagation of Systemic Inflammatory Responses into the Central Nervous System
Get PDFSepsis-associated encephalopathy (SAE) is an acutely progressing brain dysfunction induced by systemic inflammation. The mechanism of initiation of neuroinflammation during SAE, which ultimately leads to delirium and cognitive dysfunction, remains elusive. The goal of this project was to study the molecular events of SAE to capture its onset and progression into the central nervous system (CNS), and further identify the cellular players involved in mediating acute inflammatory signaling. Gene expression profiling on the cerebral vessels isolated from the brains of the mice treated with peripheral lipopolysaccharide (LPS) revealed that the cerebral vasculature responds within minutes to acute systemic inflammation by upregulating the expression of immediate early response genes, followed by activation of the NF-κB pathway. To identify the earliest responding cell type, fluorescence-activated cell sorting (FACS) was utilized to sort the immunolabelled glial and vascular cells from the brains of the mice treated with LPS at different time points and gene expression profiling was performed. Bioinformatic analysis of the sequencing data followed by further validation revealed that the cerebral endothelial cells (CECs) activation is the earliest event in the CNS and that they are the most likely source of proinflammatory mediators that could further initiate glial cell activation. This is further followed by the activation of apoptotic signaling in the CECs which is known to lead to blood brain barrier (BBB) disruption and allow the peripheral cytokines to leak into the CNS, exacerbate the gliosis and result in neuroinflammatory cascade. Together, these results model the sequential events during the advancement of systemic inflammation into the CNS, and facilitate better understanding of the interplay between the vascular and glial cells in initiating and driving acute neuroinflammation during SAE.
Systemic inflammation does lead to neuroinflammation, thereby linking the peripheral inflammatory conditions to the CNS. However, the mechanisms through which systemic inflammation exerts its effect on the CNS are poorly understood. Exosomes are small (30 to 100 nanometers) membrane bound extracellular vesicles released by most of the mammalian cells. Exosomes play a vital role in cell to cell communication. This includes regulation of inflammatory responses by shuttling mRNAs, miRNAs and cytokines both locally and systemically to the neighboring as well as distant cells to further modulate their transcriptional and/or translational states and affect the functional phenotype of those cells which have taken up these exosomes. The role of circulating blood exosomes in mediating neuroinflammation during systemic inflammation was thus studied. Serum derived exosomes from LPS-challenged mice (SDEL) were freshly isolated from the sera of the mice which were earlier treated with LPS and used to study SDEL effects on neuroinflammation. Exosomes isolated from the sera of the mice injected with saline were used as control. In vitro studies showed that the SDEL upregulate pro-inflammatory cytokine gene expression in the cell lines of microglia (BV2), astrocytes (C8-D1A) and cerebral microvascular endothelial cells (Bend.3). To further study their effects in vivo, SDEL were then intravenously injected into normal adult mice. The recipient mice that received SDEL exhibited elevated microglial activation. Moreover, increased astrogliosis, and elevated CNS expression of pro-inflammatory cytokine mRNA were observed in SDEL recipient mice. Additionally, SDEL injected directly into the cerebral ventricles resulted in significant microgliosis as well as, astrogliosis. Together, these results demonstrate a novel role of peripheral circulating exosomes in causing neuroinflammation during systemic inflammatory conditions
Conditional Loss of Engrailed 1/2 in Rhombic Lip-Derived Neurons Increases Intrinsic Rhythmicity and Decreases Overall Variability of Eupneic Respiration
Get PDFEvidence for a cerebellar role during cardiopulmonary challenges has long been established, but investigation into cerebellar involvement in eupneic breathing has been inconclusive. Given the view of the cerebellum (CRB) as a temporally coordinating structure, any investigation into the CRB during respiration must evaluate rhythm and variability of the respiratory sequence. In this study, we chose an elegant model of cerebellar neuropathology, Atoh1-En1/2 CKO, where mutant animals have conditional loss of the developmental patterning gene Engrailed 1/2 in rhombic lip-lineage neurons and exhibit a proportional scaling-down of neuron number in hypoplastic lobules of the CRB. We utilized whole-body unrestrained plethysmography to measure respiration during eupnea, and evaluated the respiratory sequence of mutant animals and their control littermates using the average rate, the coefficient of variation (CV), and a unique measure of intrinsic rhythmicity called CV2. Linear regression analyses revealed that mutant animals had decreased overall variability and increased intrinsic rhythmicity (as measured by CV and CV2, respectively) compared to their control littermates, but we found no effect of strain on average respiratory rate. Analysis also revealed modestly decreased respiratory rates, increased CV, and increased CV2 in female animals, independent of strain. These results align well with previously reported studies and add new insight into CRB involvement in eupneic respiratory rhythmicity. Although not investigated in this study, future works should consider the coordination of breathing, licking, swallowing, and whisking in order to build a more complete understanding of the relationship between the CRB and respiration
Systems Genetics and Systems Biology Analysis of Paraquat Effects in BXD Recombinant Inbred Mice
Get PDFParaquat (PQ) is a chemical herbicide that is used in many countries including the United States. It is also highly acutely toxic to humans and has been used as a means of suicide. As PQ is applied mainly in agricultural settings, it moves to soil and well water. Chronic low dose exposure via drinking water may have adverse effects on humans, including increased risk for sporadic Parkinson’s disease (sPD). The etiology of sPD is unclear and the most accepted hypothesis states it is the result of the interaction between environmental factors and genetic susceptibility. Increasing evidence led us to infer a relationship between iron metabolism in the brain, environmental toxicants like paraquat, and sPD. Our hypothesis is that variable genetic factors contribute to differential paraquat-induced iron dyshomeostasis which causes neural toxicity by producing free oxygen radicals and by other mechanisms that need to be characterized. We demonstrated here that paraquat can enter the brain and its variable cerebellar level is a result of strain and dose. This fact may contribute to set the environment to paraquat neurotoxicity through complex pathways. In this work, genetic mapping of the phenotypes revealed significant quantitative trait loci (QTL) for iron (Chr5 @ 24Mb, LOD 4.09), in which genes fall within distinct categories including iron ion homeostasis, iron ion import into cell, serine/threonine kinase activity, cellular sodium ion homeostasis, positive regulation of neuron death, among others. From the gene network, we inferred that paraquat affected not only iron regulation but also kinase activity. From the genetic mapping of proinflammatory cytokines, we obtained a QTL in Chr9 for Il-1β. Within this locus, we found a gene that has been related to risk for neurodegeneration, such as Myelin-associated oligodendrocytic basic protein (Mobp), and the Rpl14 gene, which encodes a ribosomal protein that is a component of the 60S subunit and has been related to paraquat exposure. Additionally, our work supports the idea that PQ does not necessarily activate microglia but produces other effects that lead to microglial activation. First in the chain, it must be PQ internalization to neurons (DA and non-DA) which will generate intracellular redox cycling, ROS, iron dyshomeostasis, and subsequent cell death. Following on the nomination of suggestive genes here, we are investigating paraquat effects on neuronal injury in substantia nigra in a subset of the BXD panel using immunohistochemistry. Thus, the approach would be to do an unbiased quantification of the number of tyrosine hydroxylase positive (TH+) cells in the SNpc in a subset of the BXD panel exposed to paraquat or saline. The hypothesis is that the strains showing the highest response to PQ (from this work) will show the greatest loss of tyrosine hydroxylase staining in the SNpc. This will allow us to compare our metal phenotypes in VMB, especially iron, with TH+ counts phenotypes and determine if there is a direct relationship among them and validate or complement our group of genes already determined in this work. The results reported here showed the heuristic value of systems genetics and systems biology approach in the complexity of neurotoxicology and provides clarification of pathways that may underlay sPD pathogenesis.
Abstract (Spanish) El paraquat (PQ) es un herbicida que se utiliza en muchos países, incluyendo Estados Unidos. También es muy tóxico para los humanos y se ha utilizado como medio de suicidio. El PQ se aplica principalmente en entornos agrícolas donde se traslada al suelo y al agua de estanques. La exposición crónica a bajas dosis a través del agua potable puede tener efectos adversos en los seres humanos, incluido un mayor riesgo de Enfermedad de Parkinson esporádica (EPs). La etiología de la EPs no es evidente y la hipótesis más aceptada establece que es el resultado de la interacción entre factores ambientales y susceptibilidad genética. La creciente evidencia nos llevó a inferir una relación entre el metabolismo del hierro en el cerebro, tóxicos ambientales como el paraquat y EPs. De esta manera, nuestra hipótesis es que factores genéticos variables contribuyen a la dishomeostasis del hierro diferencial inducida por el paraquat que causa toxicidad neuronal al producir radicales libres y por otros mecanismos que necesitan ser caracterizados. Demostramos en este trabajo que el paraquat puede ingresar al cerebro, con concentración variable y es el resultado de la composición genética de las sepas de ratones y de la dosis de PQ. Este hecho puede contribuir a configurar el entorno para la neurotoxicidad del paraquat a través de vías complejas.
En este trabajo, el mapeo genético de los fenotipos reveló un loci de rasgos cuantitativos (QTL) significativos para el hierro (Chr 5 @ 24Mb, LOD 4.09), en los que los genes se encuentran dentro de distintas categorías que incluyen homeostasis de iones de hierro, importación de iones de hierro a la célula, serina / treonina con actividad quinasa, homeostasis del ión de sodio celular, regulación positiva de la muerte neuronal, entre otros. De la red genética, podemos inferir que el paraquat está afectando no solo la regulación del hierro sino también la actividad de las quinasas. A partir del mapeo genético de citocinas proinflamatorias, obtuvimos un QTL en el Chr9 para Il-1β. Dentro de este locus, encontramos un gen que se ha relacionado con el riesgo de neurodegeneración, como la proteína básica oligodendrocítica asociada a mielina (Mobp), y el gen Rpl14, que codifica una proteína ribosómica que es un componente de la subunidad 60S, estos genes han sido antes relacionados con la exposición al paraquat. Además, nuestro trabajo apoya la idea de que PQ no necesariamente activa las microglías, sino que produce otros efectos que conducen a la activación de las microglías. Primero en la cadena, debe ser la internalización de PQ a las neuronas (DA y no DA) lo que generará el ciclo intracelular de reducción-oxidación, dishomeostasis del hierro y la posterior muerte celular. Siguiendo la nominación de genes sugestivos aquí, estamos investigando los efectos del paraquat sobre la lesión neuronal en la substantia nigra en un subconjunto del panel BXD utilizando inmunohistoquímica. Por tanto, el enfoque sería realizar una cuantificación imparcial del número de células positivas para tirosina hidroxilasa (TH+) en la SNpc en un subconjunto del panel BXD expuesto a paraquat o a solución salina. Nuestra hipótesis es que las cepas que muestren la respuesta más alta a PQ (en el presente trabajo) mostrarán la mayor pérdida de tinción de tirosina hidroxilasa en el SNpc. Esto nos permitirá comparar nuestros fenotipos de hierro en el cerebro medio ventral con fenotipos de conteos TH+ y determinar si existe una relación significativa entre ellos y validar o complementar nuestro grupo de genes ya determinados en este trabajo. Los resultados presentados aquí muestran el valor heurístico del enfoque de la genética y biología de sistemas en la complejidad de la neurotoxicología y proporcionan una aclaración de las vías que pueden subyacer a la patogénesis de la EPs
An Analysis of Patient-Generated Health Data in Assisting Nurses and Physicians to Better Treat Patients with Hypertension
Get PDFPatient Generated Health Data (PGHD is not new but it has gained more attention these past years due to the advent of smart devices, remote monitoring devices and many applications on various smart devices. PGHD reflects medications and treatment, lifestyle choices, and health history. Unlike traditional medical visits, where clinicians collect and manage data within their offices, PGHD is collected by patients throughout the course of their day and provides an insight of how they are responding to treatments or lifestyle choices. Examples include blood glucose monitoring or blood pressure readings using home health equipment, exercise and diet tracking using mobile applications or wearable devices such as the Fitbit or other smart watches