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OT in Pediatric Primary Care
Get PDFThis session described a program where licensed occupational therapists and master’s level OT students provide free developmental screenings to infants and young children in local pediatric medical practice. Strategies for strategies for developing relationships and bridging communication between occupational therapists, primary practice physicians, and families were reviewed
Efficacy of Smart Infusion Pumps from a Nursing Perspective
Get PDFIn today’s healthcare, intravenous (IV) therapy-related errors have become rampant and are responsible for a substantial portion of hospital injuries and deaths. In the last decade, however, since the development and implementation of “smart” IV pumps, a significant number of these IV medication errors have allegedly been reduced. The purpose of this paper is to discuss research surrounding an evaluation of the efficacy of smart IV pumps from a nursing perspective
Novel Determinants That Influence Azole Susceptibility in Candida glabrata and Candida albicans
Get PDFDespite the scientific and medical communities’ best efforts, the incidence of fungal infections in susceptible populations continues to rise. The most common cause of these opportunistic fungal infections is Candida. In fact, Candida is the fourth most common pathogen associated with nosocomial blood stream infections. Reported mortality rates for patients with candidemia vary, but have not decreased in the past fifteen years and are reported to be as high as 50%. Candida glabrata, second only to Candida albicans among Candida infections, expresses high rates of resistance to treatment with arguably the best class of currently available antifungals - the azoles.
Other available antifungals have associated toxicities, are not available as oral dosage forms or are cost prohibitive. As multidrug resistant C. glabrata have been reported, the need to find ways to overcome resistance to azoles is more pressing than ever. The work described here highlights our efforts to develop a better understanding of azole resistance in Candida, with a focus on C. glabrata, which can then be utilized to inform better strategies for decreasing or preventing resistance.
In C. glabrata clinical azole resistance is mediated almost exclusively by activating mutations in the zinc cluster transcription factor Pdr1, which controls the genes encoding the multidrug resistance transporters Cdr1, Pdh1, and Snq2. However, the specific relative contribution of these transporters to resistance is not known. In order to determine this, the SAT1 flipper method was used to delete CDR1, PDH1, and SNQ2 in a strain of C. glabrata engineered to carry a clinically relevant activating mutation in PDR1. Susceptibility testing was performed according to the CLSI guidelines with minor modifications and confirmed with Etest strips. Of the single transporter deletion strains, only CDR1 deletion resulted in decreased azole MIC. Deletion of PDH1 in combination with CDR1 resulted in a moderate decrease in MIC from that observed with deletion of CDR1 alone. SNQ2 deletion only decreased the MIC in the triple deletion strain in the absence of both CDR1 and PDH1. Deletion of all three transporters in combination decreased the MIC to the level observed in the PDR1 deletion strains for some, but not all of the azoles tested, which indicates additional Pdr1 targets likely play a minor role in this process. These results demonstrate that Cdr1 is the most important Pdr1-mediated multidrug resistance transporter for azole resistance in C. glabrata, suggesting that targeting this transporter alone might be sufficient to overcome this clinical problem.
Upc2 and Ecm22 in S. cerevisiae and Upc2 in C. albicans are the transcriptional regulators of ERG11, the gene encoding the target of azoles in the ergosterol biosynthesis pathway. Recently two homologs for these transcription factors, UPC2A and UPC2B, were identified in C. glabrata. One of these, UPC2A, was shown to influence azole susceptibility. We hypothesized that due to the global role for Upc2 in sterol biosynthesis in S. cerevisiae and C. albicans, disruption of UPC2A would enhance the activity of fluconazole in both azole-susceptible-dose dependent (SDD) and -resistant C. glabrata clinical isolates. To test this hypothesis, we constructed mutants disrupted for UPC2A and UPC2B alone and in combination in a matched pair of clinical azole-SDD and - resistant isolates. Disruption of UPC2A in both the SDD and resistant isolates resulted in increased susceptibility to sterol biosynthesis inhibitors, including a reduction in fluconazole minimum inhibitory concentration and minimum fungicidal concentration, enhanced azole activity by time-kill analysis, a decrease in ergosterol content, and downregulation of baseline and inducible expression of several sterol biosynthesis genes. Our results indicate that Upc2A is a key regulator of ergosterol biosynthesis and is essential for resistance to sterol biosynthesis inhibitors in C. glabrata. As such, the UPC2A pathway may represent a potential co-therapeutic target for enhancing azole activity against this organism.
The importance of Pdr1 in azole resistance in C. glabrata is well established. Our understanding of how Pdr1 is being regulated, however, is predominantly informed by regulation of similar systems in other organisms. In order to identify genes that interact with the Pdr1 transcriptional pathway, and influence the susceptibility of C. glabrata to fluconazole, we screened a collection of deletion mutants for those exhibiting increased resistance to fluconazole. Deletion of the gene coding for a protein homologous to the S. cerevisiae J protein Jjj1 resulted in decreased fluconazole susceptibility. We used the SAT1 flipper method to generate independent deletion mutants for JJJ1 in a SDD clinical isolate. Expression of both CDR1 and PDR1 was increased in the absence of JJJ1. In the absence of CDR1 or PDR1, deletion of JJJ1 had only a modest effect on fluconazole susceptibility. Transcriptional profiling using RNA-Seq revealed up-regulation of genes of the Pdr1 regulon in the absence of JJJ1. Jjj1 appears to be a negative regulator of fluconazole resistance in C. glabrata and acts primarily through up-regulation of the ABC transporter gene CDR1 via activation of the Pdr1 transcriptional pathway.
Unlike C. glabrata which has essentially one mechanism of resistance, in C. albicans clinical azole resistance can be attributed to multiple mechanisms, often in combination. The RTA3 gene, coding for a member of the Rta1p-like lipid-translocating exporter family, is coordinately upregulated with the ABC transporter genes CDR1 and CDR2 in azole-resistant clinical isolates of C. albicans that carry activating mutations in the transcription factor Tac1p. We show here that deleting RTA3 in an azole-resistant clinical isolate carrying a Tac1p activating mutation lowered fluconazole resistance by two-fold, while overexpressing RTA3 in an azole-susceptible clinical isolate resulted in enhanced fluconazole tolerance associated with trailing growth in a liquid microtiter plate assay. We also demonstrate that an Rta3p-GFP fusion protein localizes predominantly to the plasma membrane, consistent with a putative function for Rta3p as a lipid translocase
Protein Trafficking of BK Channel β1 Subunits in Cerebral Artery Myocytes
Get PDFRationale: Large-conductance calcium (Ca2+)-activated potassium channels (BK) are expressed in arterial myocytes to control arterial contractility. It is composed of pore- forming BKα and auxiliary β1 subunits. Auxiliary β1 subunits associate with BKα which modulate Ca2+ sensitivity of BK channel. Previous data showed that BKα locates at cell membrane, whereas β1 subunits are primarily intracellular which regulated by Rab11A- positive recycling endosomes. Endothelin-1 (ET-1), a vasoconstrictor, induces contraction of myocytes. ET-1 inhibits BK channel but mechanisms are not fully understood. It is unclear that vasoconstrictors regulate the cellular distribution of BK channels. Furthermore, BK channels are involved in hypertension. Hypertension increases risk of major cardiovascular and cerebrovascular events, such as stroke and mental dysfunction. During hypertension, cerebral arteries have high myogenic tone and are less responsive to vasodilators, including nitric oxide (NO). The regulation of arterial contractility by BK channels is altered during hypertension, although mechanisms involved are also unclear.
Objective: Test the hypothesis that ET-1 inhibits β1 surface trafficking in myocytes via activation of PKC. Test the hypothesis that activation of PKC directly modulates Rab11A through phosphorylation. Furthermore, test the hypothesis that trafficking of pore- forming BK channel (BKα) and auxiliary β1 subunits contributes to pathological changes in contractility in cerebral arteries of stroke-prone spontaneously hypertensive rats (SP- SHRs).
Methods and Results: ET-1 decreased NO-induced or depolarization-induced surface β1 expression and association with BKα in myocytes through activation of protein kinase C (PKC). Total β1, total BKα proteins or surface BKα was not altered by ET-1. Rab11A regulates β1 protein trafficking in Rab11A-positive recycling endosome. ET-1 reduced Rab11 activity via phosphorylation. Five probable phosphorylated sites on Rab11A were identified, among which Ser177 has highest probability. A phosphorylation-mute Rab11A construct (Rab11A S177A) or wild-type Rab11A construct similarly increased total Rab11A protein in transfected myocytes. Rab11A S177A inhibited ET-1-reduced Rab11A activity and decreased β1 protein trafficking. Rab11A S177A reversed PKC- dependent block of single BK channels and transient BK currents in myocytes. Rab11A S177A partially blocked ET-1-induced vasoconstriction. In contrast, NO-induced surface-trafficking of β1 subunits, BK current activity and vasodilation did not involve Rab11A S177. Our data also indicate that the amounts of total and surface BKα and β1 subunits were similar in unstimulated arteries of SP-SHRs and age-matched, normotensive Wistar-Kyoto rat controls. In contrast, the stimulated surface-trafficking of β1 subunits by either NO (sodium nitroprusside, SNP) or membrane depolarization was inhibited in SP-SHR arteries. BIM, a PKC inhibitor, and overexpression of a mutant Rab11A construct that cannot be phosphorylated by PKC at serine 177 (Rab11A S177A) restored the stimulated surface-trafficking of β1 subunits. PKC-mediated inhibition of β1 trafficking prevented BK channel activation by NO in arterial myocytes of SP-SHRs and this was restored by the expression of Rab11A S177A, but not by Rab11A. Vasodilation to NO and lithocholate, an activator of β1 subunit-containing BK channels, was inhibited in pressurized arteries of SP-SHRs. Vasodilation to these agents was reestablished by BIM in SP-SHR arteries.
Conclusions: In smooth muscle cell, ET-1 activates protein kinase C which phosphorylates Rab11A at Ser177 to reduce Rab11A activity. Inhibition of Rab11A blocks anterograde trafficking of β1 subunits to associate with BKα on cell surface. Less β1 subunits reduces Ca2+ sensitivity of BK channel and transient BK channel currents which leads to vasoconstriction. Spontaneously active PKC inhibits β1 subunit trafficking in arterial myocytes and is responsible for dysfunctional NO-induced BK channel activation and vasodilation in cerebral arteries of SP-SHRs
Impact Information Governance has on Healthcare Organizations
Get PDFThe purpose of this study evaluated the impact of information governance (IG) on healthcare organizations. Objectives and limitations were derived from literature reviews, case studies, and surveys. A methodology of evaluation research with a focus on summative evaluations was conducted. The population study consisted of health information management (HIM) professionals, consultants, data analyst, and other healthcare professionals. The findings from the research provided significant evidence supporting the value IG programs possess along with the benefits healthcare organizations gained with the adoption of the IG initiative
Joint Coordination Variability In Anterior Cruciate Ligament Reconstructed Subjects During Stair Ambulation Using a Vector Coding Technique
Get PDFAnterior cruciate ligament (ACL) rupture is a common injury, with an estimated incidence of 120,000 to 200,000 per year in the United States. ACL reconstruction surgery is the standard treatment for this injury to restore knee joint stability and function. While surgical reconstruction has been shown to restore laxity of the knee, current literature lacks consensus on return to normal knee joint kinematics following surgery. Additionally, re-injury is a major risk for those who return to sports activity after reconstruction surgery. Dynamical systems methods for quantifying joint coordination variability have been explored as a method for detecting differences between ACL reconstructed (ACLR) subjects and healthy control subjects. Specifically, altered joint coordination variability has been linked to lower extremity instability, which may indicate re-injury risk.
The aim of this study was to assess joint coordination and joint coordination variability using a vector coding technique in ACLR subjects after recovery and return to normal activity. Our hypothesis was that joint coordination variability of ten selected intra-limb knee-knee and knee-hip couplings would be altered in the ACLR group compared to a group of healthy control subjects based on previous findings using similar methods.
Thirty subjects (15 ACLR and 15 normal) were analyzed using a motion capture camera system and force plates. Subjects were asked to ascend a staircase in a step-over-step manner at a self-selected pace, turn around on the elevated platform, then descend from the platform down the steps and return to the starting location. We employed a vector coding method using a custom Matlab script to measure coupling angle variability of knee-knee and hip-knee coupled motion during the stair activity. Individuals with ACLR were found to have differences in joint coordination variability (both increased and decreased) in 5 of the 10 joint couplings analyzed as compared with a healthy control group during the stair descent activity.
The majority of differences were found to be reductions in variability in the ACLR group as compared with controls. It is believed that there is an optimal amount of variability in any motor system that differentiates between the ability to adapt to environmental instability and the risk for injury. Reduced joint coordination variability indicates avoidance of a particular movement and results in the inability to adapt movement strategies in a dynamic environment. Decreased variability in ACLR subjects has also been linked to re-injury in at least one prospective study. These results combined with previous works provide insight into coordinative function after ACLR and may be useful in improving rehabilitation protocols following surgery as well as identifying those at risk of re-injury
Development of Multiple Microemulsion Eye Drops for Sustained Release of New Glaucoma Drug
Get PDFPersistent or repeated elevation of intraocular pressure (IOP) is a primary risk factor of visual field loss in glaucoma, therefore IOP reduction is the first-line therapeutic option in the disease management. Unfortunately, the current therapies are associated with a lot of deficiencies including several daily dosing, reduced efficacy and systemic side effects all of which resulted in poor patient compliance. Previously we have identified Calcium voltage-gated channel auxiliary subunit Alpha2delta 1 gene (Cacna2d1) as a novel modulator of IOP and confirmed that pregabalin targeted CACNA2D1 in eye tissues (ciliary body and trabecular meshwork) to lower IOP in a dose-dependent manner. The research presented in this dissertation aimed to develop a once-daily ocular pregabalin-loaded multiple water-in-oil-in-water microemulsion eye drops. Several in vitro and in vivo evaluations were used to characterize the prepared ophthalmic formulations. Also stability study at 5°C, 25°C, 30°C and 40°C was conducted for four months. All the formulations components were carefully selected to be highly biocompatible that provided a highly transparent eye drops with a miniscule droplet size
Signaling Induced by Inflammatory Mediators in the Rodent Pulmonary Microvasculature
Get PDFAcute lung inflammation (ALI), stemming from a disproportionate and detrimental immune response, may arise from or complicate other disease states, leading to the often-fatal acute respiratory distress syndrome (ARDS). Because of the many culpable factors and differing points of induction, pinning down the signaling mechanisms involved in the morbidity of this disorder as well as defining an effective treatment has proved problematic. However, the most detrimental characteristic of this condition is seen regardless of the development of the response: increased microvascular permeability. Because of the architecture and the size of the pulmonary microvascular network, the lungs have a resident, sequestered population of leukocytes that are able to rapidly respond to injury or infection, but may also contribute to the pathology of ALI/ARDS by increasing endothelial barrier dysfunction. Many inflammatory mediators dictate the course and gravity of the response by inducing endothelial cytoskeletal reorganization, such as induction of actin stress fibers, cell rounding and contraction, and dissociation of interendothelial junctions.
Thrombin is a well-studied mediator that has been shown to be barrier-disruptive rapidly increases microvascular permeability. Sphingosin-1-phosphate (S1P) is a more novel, less understood mediator that has been shown to mediate basal vascular permeability as well as to enhance barrier integrity in inflammation. Inflammatory signaling may also expand throughout the lungs through intercellular communication via gap junctions composed of connexins, such as Connexin 43 (Cx43). Herein, we explored how intercellular communication through Cx43-containing gap junctions mediates thrombin-induced signaling as well as the interplay between thrombin- and S1P- induced signaling on the pulmonary microvascular barrier.
We isolated and perfused lungs from rats and mice, a physiologically-relevant model to study lung inflammation. We found that focal micropuncture instillations of thrombin were able to induce responses related to hyperpermeability (including, changes in intracellular Ca2+, increased F-actin polymerization, and increased reactive oxygen species generation) both in microvessels directly treated with thrombin and those far outside the instilled region (up to 1000 μm away), and the expansion of signaling into the untreated microvessels was due to intercellular communication mediated by Cx43. For the F-actin polymerization response, we determined that the specific second messenger being communicated and propagating the thrombin-induced increase was inositol trisphosphate (IP3). We also found that, though thrombin induced increases in mean Ca2+in cultured cells, it instead induced increases in the amplitude of cytosolic Ca2+ oscillations in pulmonary microvessels. While we observed that untreated primary pulmonary microvascular endothelial cells and pulmonary microvessels from mice lacking endothelial Cx43 displayed higher levels of the S1P receptor, S1P2, thrombin induced an increase in S1P2 expression that was dependent on the presence of Cx43. While S1P itself was able to partially rescue barrier integrity following thrombin treatment, we show for the first time that S1P2 signaling substantially contributes to thrombin-induced endothelial hyperpermeability, and that inhibiting S1P2 significantly reduced thrombin-induced permeability increases
Changing the Conversation from Avoiding Predatory Journals to Finding and Evaluating the Right Journal
Get PDFObjective: Predatory publishing is a trending topic in academia. Librarians all over are having conversations with faculty on how to steer clear of predatory publishers. But helping avoid predatory journals doesn’t meet the goal of having an article published. Now is the time to explore changing the conversation from predatory publishing to finding and evaluating the right journal. Methods: Last year librarians went to departmental meetings to present a cautionary tale of the predatory publisher. Outlandish emails from predatory journals were shared, along with what to look for when determining whether or not a journal publisher is legitimate. But just knowing how to steer clear of the predators did not answer the question, “Which journal should I publish in?” To help faculty answer this question, the library held two hands on workshops for faculty, staff and residents. Librarians taught participants how to determine their goals and criteria for publishing, how to compare their article to the aim and scope of a journal and make a determination on whether or not the journal was the right fit for them. As participants answered the questions on the worksheet they built a list of criteria for selecting the right journal for their article. Results: Participants were able to find and evaluate journals for their manuscripts, while still steering clear of predatory publishers. Conclusions: In the “publish or perish” era, it is important for faculty members to publish in reputable journals, but it is equally important for them to find the best journal to meet their publishing goals. Librarians can move the conversation beyond predatory journals by giving faculty the tools and skills they need to find and evaluate the right journal