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Assessing Our Judgement: Comparing Librarian and Allied Health Professionals’ Evaluation of Relevance of Search Results
Get PDFObjectives: Information needs, literature searching, librarian’s and requestor’s perception
How Laboratory Informatics has Impacted Healthcare Overall
Get PDFHealth information technology has improved key areas of healthcare such as academia, research, and practice. Technology is one of the key driving forces in healthcare that is set to enhance the overall provider-patient experience. The future of healthcare is aimed at improving patient satisfaction, quality of care, and practice methods. Laboratory information systems (LIS) is a fundamental component of the diagnostic or pathology department (Henricks, 2016). In the era, where laboratory reports have become complex and high-dimensional, the need to develop and implement a cost-effective platform or tool to collect, process, store, and manage such processes is required. A systematic review of literature was conducted, wherein relevant articles associated with laboratory information systems. The study was based on a qualitative design, wherein key concepts or themes from articles and reports were qualitatively identified. The advantages of laboratory information systems can be considered as a platform to enhance patient satisfaction, quality care, and patient safety
Rheological Studies of Injectable Thermoresponsive Biodegradable Hydrogels and Porcine Ocular Tissues
Get PDFThis research has evaluated the rheological properties of two types of materials which include (i) semi-synthetic polymer-based injectable hydrogels [P(NIPAAm-co-DEX-Lactate HEMA) and P(NIPAAm-co-HA-AEMA)], and (ii) biological tissues (porcine ocular tissues).
A series of thermoresponsive and biodegradable in situ hydrogel based on N-isopropyacrylamide (NIPAAm) monomer and hydrolytically degradable oligolactate Dextran-lactate-HEMA or Hyaluronic acid (HA)-AEMA macromer were investigated as encapsulation matrices (scaffolds) for DPSCs/ADSCs and assess their applicability in dental/retinal tissue engineering. The rheological properties of the hydrogels were strongly dependent on the reaction conditions and composition of the hydrogels. Both the hydrogels exhibited linear viscoelasticity, and the values of storage moludus (G´) at 1 Hz appeared in the range of 15-35 Pa for P(NIPAAm-co-DEX-Lactate HEMA) gels and 20-40 Pa for P(NIPAAm-co-HA-AEMA) gels at 15 mg·mL-1 concentration. No significant differences were found for the hydrogels prepared with the HA or dextran at the same concentration and monomer to macromer ratio (19:1). The hydrogels were nontoxic to DPSCs and ADSCs at a concentration up to 15 mg·mL-1, and in vitro survival studies using MTT and DAPI indicated that both DPSCs and ADSCs have favorably adhered and proliferated within the dextran and HA-based hydrogels. Survival of the DPSCs/ADSCs in the hydrogels, growth and morphology make these scaffolds a viable option for using as a biological scaffold for tissue engineering.
Since the functionality of the ocular tissues closely depends on their biomechanical properties, the rheological properties of the ocular tissues at different stages of development (preterm, neonatal and adult stage) is of therapeutic interest and has not been thoroughly investigated. This study has investigated the shear properties of porcine cornea, sclera and vitreous under strain and frequency sweep. All three tissue types at different stages have shown linear viscoelastic region under strain sweep. The G´ of cornea and vitreous weakly varied between neonatal and preterm, however, the adult cornea (~1.3-fold) and vitreous (~1.8-fold) showed significant higher moduli. On the other hand, the G´ of the sclera increased significantly with the developmental stage of the tissue, (preter
Effect of Comorbidities on HIV-1 Pathogenesis in Monocytic Cells
Get PDFThe advent of antiretroviral therapy (ART) has substantially increased the life span of people living with HIV-1 (PLWH). However, the presence of comorbid conditions such as high prevalence of drug abuse and coinfections have deteriorated the health outcomes in PLWH and progression of HIV-1 infection to AIDS. In this study, we will be focusing on the independent effect of two major comorbidities: cigarette smoking and human papilloma virus (HPV) coinfection on HIV-1 replication and pathogenesis in monocytic cells.
The prevalence of smoking is approximately 3-times higher in PLWH compared to the general population. Scientific evidences suggest that smoking aggravates HIV-1 pathogenesis and leads to decreased responses to ART. However, the exact mechanism by which smoking enhances HIV-1 replication is still not clear. The Kumar group has demonstrated the role of nicotine, at least in part, on HIV-1 replication in monocytic cells via cytochrome P450 (CYP)-mediated oxidative stress pathway. They have also shown the role of cigarette smoke condensate (CSC), which contains numerous organic compounds such as polyaryl hydrocarbons (PAHs), on cytotoxicity and HIV-1 replication in monocytic cells. Therefore, the goal in this study was to identify active ingredient of CSC, especially PAHs, which is responsible for cytotoxicity and HIV-1 replication in monocytic cells, and their underlying mechanism. PAHs such as benzo(a)pyrene (BaP), naphthalene (NPh), phenanthrene (Phe), benzo(a)antharacene (BeA), and benzo(b)fluoranthene (BeF) are known carcinogens present in cigarette smoke. As a first part of our study, we examined the relative effect of these constituents on the cytotoxicity of monocytic cells and the possible mechanism of PAH-mediated cytotoxicity. We examined the acute (6-24 hours) and chronic (7 days) effects of these PAHs on the expression of cytochromes P450 (CYPs), oxidative stress, and cytotoxicity. The treated cells were examined for mRNA and protein levels of CYPs (1A1 and 3A4) and antioxidants enzymes (AOEs) superoxide dismutase-1 (SOD1) and catalase. Further, we assessed the levels of reactive oxygen species (ROS), caspase-3 cleavage activity, and cell viability. We performed these experiments in U937 cell lines and/or primary monocytic cells. Of the five PAHs tested, after chronic treatment only BaP (100 nM) showed a significant increase in the expression of CYP1A1, AOEs (SOD1 and catalase), ROS generation, caspase-3 cleavage activity, and cytotoxicity. However, acute treatment with BaP showed only an increase in the mRNA expression of CYP1A1. These results suggested that of the five PAHs tested, BaP is the major contributor to the toxic effect of PAHs in monocytic cells, which is likely to occur through CYP and oxidative stress pathways.
Secondly, we investigated a molecular mechanism that would explain BaPinduced HIV-1 replication. We hypothesized that CYP-mediated BaP metabolism generates ROS, and the resultant oxidative stress aggravates HIV-1 replication. As expected, we observed ~4-fold increase in HIV-1 replication in differentiated U1 (HIV-1- infected U937) monocytic cell lines and human primary macrophages after chronic BaP exposure. We also observed ~30-fold increase in the expression of CYP1A1 at mRNA level, ~2-fold increase in its enzymatic activity, as well as, an elevated ROS level and cytotoxicity in U1 cells. The knock-down of the CYP1A1 gene using siRNA and treatment with selective CYP inhibitors and antioxidants significantly reduced HIV-1 replication. Further, we observed a nuclear translocation of NF-κB subunits (p50 and p65) after chronic BaP exposure, which was reduced by treatment with siRNA/inhibitors of CYP and antioxidants. Suppression of NF-κB pathway using specific NF-κB inhibitors also significantly reduced HIV-1 replication. Together, our results suggest that BaP enhances the HIV-1 replication in macrophages by CYP-mediated oxidative stress pathway via NF-κB signaling cascade.
Thirdly, we explored the underlying mechanism by which HPV increases HIV-1 pathogenesis. HPV infection is one of the major factors that contribute to a reduced suppression of the virus in HIV-1 patients. There is a high prevalence of comorbidity of HIV-1 and HPV (which leads to cervical cancer) among HIV-1-infected population. We proposed that exosomes secreted from HPV-infected cervical cancer cells exacerbate HIV-1 replication in HIV-1-infected macrophages. To test the hypothesis, we treated U1 cells (HIV-1-infected monocytic cell line) with the cell culture supernatant (CCS) obtained from caski cells (HPV-infected cervical cancer cells). We observed an ~2-fold increase in HIV-1 replication in the treated U1 cell. We also observed a significant increase in the expression of CYPs (CYP 1A1 and 2A6) at the mRNA level. However, we did not observe any significant change in the expression of CYPs as well as antioxidants enzymes (catalase, PRDX6) at the protein level. Furthermore, we isolated exosomes from the caski cell culture supernatant and observed the presence of CYPs (1A1, 2A6), SOD1 and HPV protein HPV16 E6 in caski exosomes. The exosomes derived from caski cells (CCS-Exo) significantly reduced cytotoxicity, while it increased HIV-1 replication in U1 cells. Treatment of antioxidant such as resveratrol, CYP1A1 inhibitor (ellipticine) and CYP2A6 inhibitor (Tryptamine) including chemodietary agents such as curcumin (20 μM) and curcubitacin-D (0.1 μM), significantly reduced the CCS and CCS-Exo mediated HIV-1 replication in U1 cells. These results suggest the role of specific CYP-induced oxidative stress pathway in HIV-1 replication. Altogether, we demonstrated that cervical cancer cells exacerbate HIV-1 replication in monocytic cells via transferring oxidative stress factors such as CYPs and HPV oncoproteins through exosomes. We also showed that the viral replication undergoes via a CYP-mediated oxidative stress pathway and it can be reduced by treatment of chemodietary agents like curcumin and Cucurbitacin-D. The present study therefore, illustrates that comorbidities such as smoking and HPV coinfection contribute to HIV-1 replication and pathogenesis in monocytic cells via a CYP-mediated oxidative stress pathway. The study also provides scientific rationale for the development of novel therapeutic treatment for PLWHs with these comorbidities by targeting CYP and specific oxidative stress pathway
Piloting Consumer Health Resources to Nurse and Patient Educators
Get PDFObjective: The objective of this project is to pilot a consumer health resources train the trainer course and accompanying online guide to nurse and patient educators. Methods: The Clinical Services Librarian and Outreach Coordinator at the University of Arkansas for Medical Sciences proposed a plan to educate the nurse and patient educators in the hospital on reliable consumer health resources. Partnerships were formed within the institution with patient educators, patient advocates, and patient- and family-centered care. Librarians created a course presenting general consumer health resources from the National Library of Medicine as well as other reliable sites. The course was granted nursing, dietician, and patient educator continuing education credit. Parallel with the course, an online resource was built using LibGuides software. The LibGuide contains information on both general and specific health issues, based on local needs. The course walks participants through the guide and was piloted in local hospitals with patient and nurse educators. Results: The course and online guide have been completed and classes are being scheduled at both UAMS and the two local Veterans Administration hospitals. The course has been well received and participant scores have shown an increase between the pre- and post-tests. Conclusions: The course and guide received support from all areas of nursing as well as interest from outside hospitals. Future plans include expansion of the online guide and working with nurse and patient educators in hospitals and clinics throughout the state
The Future of Measuring Scholarly and Societal Impact in the Health Sciences: Exploring Dimensions in Non-Traditional Algorithms
Get PDFObjective: To provide an overview of evaluating scientific scholarly impact among researchers in the health sciences. Librarians, as department liaisons, are a natural choice for guiding faculty, students, and tenure and promotion committees in understanding and responsibly applying altmetrics and bibliometrics, including the Relative Citation Ratio (RCR), to evaluate the impact of contemporary health sciences scholars. Background: Scholars in the health sciences, particularly clinician-researchers, who divide their time among patient care, education, as well as academic service, have less time for research than other scientists. Thus, citation patterns vary across the disciplines, possibly placing clinicians at a disadvantage when traditional bibliometrics are used to determine scholarly, as well as societal impact. Judicious use of altmetrics can complement bibliometrics and citation analysis to provide a clearer picture of the scholarly and societal impact of clinician-researchers. The RCR can be a helpful counterpart to altmetrics, because it normalizes across the disciplines, compensating for differences in citation patterns and is easily calculated using NIH’s iCite. Design: Discussion Paper. Data sources: Published literature in the health, information sciences, communications, and informatics disciplines. Implications for Health Sciences Librarians: Health sciences librarians can consult with faculty, students, and committees on best practices for using altmetrics to help determine scholarly impact. This paper will illustrate various means of using social media and incorporating altmetrics into clinicians’ curriculum vitae and grant proposals. It will also review the strengths, limitations and implications of using them. In addition, librarians can introduce the RCR to their departments and demonstrate iCite in calculating the RCR. Conclusion: Both altmetrics and RCR have great potential for showing a more complete and accurate picture of the scholarly and societal impact of researchers who work in the health sciences and librarians can take the lead in managing this evolution
Biodegradable Polymeric Biomaterials in Different Forms for Long-acting Contraception and Drug Delivery to the Eye and Brain
Get PDFEfficacy of many of the new and existing therapeutics is often hampered by the lack of an effective and compliant method of delivery. Typically, drugs have poor water solubility, short half-lives, and low permeability across the biological membranes. The result is low bioavailability of the drugs at the target site and can cause toxicity and side effects at high doses. Often the conventional dosage forms fail to overcome these limitations. In the recent decades, biodegradable polymeric drug delivery systems have emerged as promising candidates to solve the challenges of poor solubility, low permeability and sustained release owing to the advantages of biocompatibility, versatility, and tunable drug release. Polyesters and polysaccharides are the most common polymers that were explored for drug delivery applications because of their unique advantages including non-toxic nature, wide availability, relatively low cost, and flexibility in chemistry. Although a major progress has been in the field of drug delivery, still there are unmet medical needs which require new materials for delivering drugs such as, injectable systems that can achieve long-term contraception (five months or longer) at low cost, and drug delivery systems that can enhance the permeability of drugs across ocular/blood-brain barriers and sustain release as well for treating chronic diseases such as diabetic retinopathy in the eye and Alzheimer’s disease in the brain. Therefore, this research has evaluated the potential of different biodegradable polymeric biomaterials based on polyesters or polysaccharides for long-acting contraception and drug delivery to the eye and brain to resolve the issues such as poor compliance and adherence to the existing contraceptive dosage forms or poor solubility and permeability of the drugs across ocular/blood-brain barriers. The first system includes polyester-based injectable in situ forming depot systems (ISD) for long-acting contraception. The aim of this project was to develop injectable ISD system containing levonorgestrel (LNG) for contraceptive effect for five months or longer after single shot that helps to reduce unintended pregnancies with high patient compliance and low cost. A series of LNG-containing ISD formulations were designed by employing unique strategies which include the use of poly(lactic acid-co-glycolic acid), poly(lactic acid) with different biodegradable properties, and blends of these polyesters, use solvent mixtures of N-methyl-2-pyrrolidone, triethyl citrate, benzyl benzoate, and vary the polymer/solvent ratios, and various drug loadings. The formulations were evaluated for viscosity, initial burst, in vitro and in vivo long-term release. In vivo investigation in rats showed the sustained-release pharmacokinetic profile of LNG from the ISD formulations for at least five months and continued for more than seven months depending on the composition, and the vaginal cytology studies have demonstrated that formulations have successfully suppressed the rat estrous cycle. After the end of the treatment, a rapid and predictable return of fertility was observed in rats. The optimized lead formulation has shown promising injectability (23 G) and low initial in vivo burst profiles. The results suggested that the developed LNG-ISD formulations have a great potential for developing into future robust affordable long-acting contraceptive products for improving patient compliance and adherence. Another type of polymeric biomaterial systems that were evaluated in this study includes polysaccharide-based biodegradable nanoparticles for drug delivery across ocular and blood-brain barriers. Depending on the need of the therapeutic application, two types of polysaccharide-based nanoparticles were investigated for their drug delivery feasibility which includes: (a) Poly(N-isopropylacrylamide-co-Dextran-lactateHEMA) nanogels for the potential delivery of hydrophilic peptide (insulin) across ocular barriers for the treatment of diabetic retinopathy. The in vitro, and ex vivo studies showed that the developed nontoxic nanogels have great potential to enhance the drug permeability across ocular barriers including the in vitro retinal pigment epithelium, sclera and cornea barriers for treating diabetic retinopathy; and (b) β-cyclodextrin-poly(β-amino ester) nanoparticles as potential drug carriers to enhance the solubility and blood-brain barrier (BBB) permeability of 17-N-allylamino-17-demethoxygeldanamycin (17-AAG) to treat Alzheimer’s disease. The nanoparticles sustained the release of 17-AAG for at least one week in vitro and showed increased permeability (2-fold) of the 17-AAG across BBB in vivo in mice, and resulted in enhanced expression of the Hsp70 protein in the brain. In conclusion, the developed biodegradable polymeric biomaterials have shown potential to be used in long-acting contraception and drug delivery to the eye and brain
Automatic Activation of Phonological Templates for Native but Not Nonnative Phonemes: An Investigation of the Temporal Dynamics of Mu Activation
Get PDFModels of speech perception suggest a dorsal stream connecting the temporal and inferior parietal lobe with the inferior frontal gyrus. This stream is thought to involve an auditory-motor loop that translates acoustic information into motor/articulatory commands and is further influenced by decision making processes that involve maintenance of working memory or attention. Parsing out dorsal stream’s speech specific mechanisms from memory related ones in speech perception poses a complex problem. Here I argue that these processes may be disentangled from the viewpoint of the temporal dynamics of sensorimotor neural activation around a speech perception related event.
Methods: Alpha (~10Hz) and beta (~20Hz) spectral components of the mu () rhythm, localized to sensorimotor regions, have been shown to index somatosensory and motor activity, respectively. In the present work, event related spectral perturbations (ERSP) of the EEG -rhythm were analyzed, while manipulating two factors: active/passive listening, and perception of native/nonnative phonemes. Active and passive speech perception tasks were used as indexes of memory load employed, while native and. nonnative perception were used as indexes of automatic top-down coding for sensory analysis.
Results: Statistically significant differences were found in the oscillatory patterns of components between active and passive speech perception conditions with greater alpha and beta event related desynchronization (ERD) after stimuli offset in active speech perception. When compared to listening to noise, passive speech perception presented significantly (pFDR
Conclusion: These findings suggest that neural processes within the dorsal auditory stream are functionally and automatically involved in speech perception mechanisms. While its early activity (shortly after stimuli onset) seems to be importantly involved with the instantiation of predictive motor/articulatory internal models that help constraining speech discrimination, its later activity (post-stimulus offset) seems essential in the maintenance of working memory processes