Perception of Healthcare Access and Utility of Telehealth Among Parkinson's Disease Patients.

Regional patient and physician density patterns pose problems to accessing care for people with Parkinson's disease, though telehealth may improve access. We surveyed and conducted a focus group for people with Parkinson's disease in Interior British Columbia regarding barriers to neurological care. Eighteen individuals completed the survey and seven parties joined the focus group. Perceived barriers include cost and difficulty of travel, wait times, and lack of specialized services outside large cities. 80% of participants (95% CI 64-96) would likely use telehealth for follow-up neurologist appointments. This sample of people with Parkinson's disease reports willingness to use telehealth to reduce travel and improve access to specialty care.

Interstitial Pulmonary Edema Assessed by Lung Ultrasound on Ascent to High Altitude and Slight Association with Acute Mountain Sickness: A Prospective Observational Study.

Background: Acute mountain sickness (AMS) is a common disease that may have a pulmonary component, as suggested by interstitial pulmonary edema quantified by the B-line score (BLS) on ultrasound (US). This subclinical pulmonary edema has been shown to increase with ascent to high altitude and AMS severity, but has not been prospectively associated with AMS incidence in a large prospective study. Materials and Methods: This prospective observational study was part of a randomized controlled trial enrolling healthy adults over four weekends ascending White Mountain, California. Subjects were assessed by lung US and the Lake Louise Questionnaire at 4110 ft (1240 m), upon ascent to 12,500 ft (3810 m), and the next morning at 12,500 ft (3810 m). Results: Three hundred five USs in total were completed on 103 participants, with 73% total incidence of AMS. The mean (±standard deviation) BLS increased from baseline (1.15 ± 1.80) to high altitude (2.56 ± 2.86), a difference of 1.37 (±2.48) (p = 0.04). Overall BLS was found, on average, to be higher among those diagnosed with AMS than without (2.97 vs. 2.0, p = 0.04, 95% confidence interval [CI] -∞ to -0.04). The change in BLS (ΔBLS) from low altitude baseline was significantly associated with AMS (0.88 vs. 1.72, r2 = 0.023, 95% CI -∞ to -0.01, p = 0.048). Conclusions: Interstitial subclinical pulmonary edema by lung US was found to have a small but significant association with AMS.

Altered Calcium Handling and Ventricular Arrhythmias in Acute Ischemia.

Acute ischemia results in deadly cardiac arrhythmias that are a major contributor to sudden cardiac death (SCD). The electrophysiological changes involved have been extensively studied, yet the mechanisms of ventricular arrhythmias during acute ischemia remain unclear. What is known is that during acute ischemia both focal (ectopic excitation) and nonfocal (reentry) arrhythmias occur, due to an interaction of altered electrical, mechanical, and biochemical properties of the myocardium. There is particular interest in the role that alterations in intracellular calcium handling, which cause changes in intracellular calcium concentration and to the calcium transient, play in ischemia-induced arrhythmias. In this review, we briefly summarize the known contributors to ventricular arrhythmias during acute ischemia, followed by an in-depth examination of the potential contribution of altered intracellular calcium handling, which may include novel targets for antiarrhythmic therapy.

Cardiorespiratory fitness as a predictor of intestinal microbial diversity and distinct metagenomic functions.

BACKGROUND: Reduced microbial diversity in human intestines has been implicated in various conditions such as diabetes, colorectal cancer, and inflammatory bowel disease. The role of physical fitness in the context of human intestinal microbiota is currently not known. We used high-throughput sequencing to analyze fecal microbiota of 39 healthy participants with similar age, BMI, and diets but with varying cardiorespiratory fitness levels. Fecal short-chain fatty acids were analyzed using gas chromatography. RESULTS: We showed that peak oxygen uptake (VO2peak), the gold standard measure of cardiorespiratory fitness, can account for more than 20 % of the variation in taxonomic richness, after accounting for all other factors, including diet. While VO2peak did not explain variation in beta diversity, it did play a significant role in explaining variation in the microbiomes' predicted metagenomic functions, aligning positively with genes related to bacterial chemotaxis, motility, and fatty acid biosynthesis. These predicted functions were supported by measured increases in production of fecal butyrate, a short-chain fatty acid associated with improved gut health, amongst physically fit participants. We also identified increased abundances of key butyrate-producing taxa (Clostridiales, Roseburia, Lachnospiraceae, and Erysipelotrichaceae) amongst these individuals, which likely contributed to the observed increases in butyrate levels. CONCLUSIONS: Results from this study show that cardiorespiratory fitness is correlated with increased microbial diversity in healthy humans and that the associated changes are anchored around a set of functional cores rather than specific taxa. The microbial profiles of fit individuals favor the production of butyrate. As increased microbiota diversity and butyrate production is associated with overall host health, our findings warrant the use of exercise prescription as an adjuvant therapy in combating dysbiosis-associated diseases.

Review of the Evolution of Medical Information in Light of Changes in the External Landscape.

Over the past 25 years, biopharmaceutical companies have faced and adapted to an external landscape that has grown increasingly complex and challenging. Medical information departments have played a fundamental role in the globalization process through their development of multichannel customer-facing resources that address the complexities with innovative solutions. The authors conducted a survey to determine key components of the globalization of medical information departments in large biopharmaceutical companies. In this article, they present survey findings and propose key components to the globalization process in medical information. Finally, they offer considerations for providing more patient-focused responses and processes for evaluating the impact of the medical information department in a global framework through the multifaceted measurement of customer satisfaction.

Regulation of PERK signaling and leukemic cell survival by a novel cytosolic isoform of the UPR regulator GRP78/BiP.

The unfolded protein response (UPR) is an evolutionarily conserved mechanism to allow cells to adapt to stress targeting the endoplasmic reticulum (ER). Induction of ER chaperone GRP78/BiP increases protein folding capacity; as such it represents a major survival arm of UPR. Considering the central importance of the UPR in regulating cell survival and death, evidence is emerging that cells evolve feedback regulatory pathways to modulate the key UPR executors, however, the precise mechanisms remain to be elucidated. Here, we report the fortuitous discovery of GRP78va, a novel isoform of GRP78 generated by alternative splicing (retention of intron 1) and alternative translation initiation. Bioinformatic and biochemical analyses revealed that expression of GRP78va is enhanced by ER stress and is notably elevated in human leukemic cells and leukemia patients. In contrast to the canonical GRP78 which is primarily an ER lumenal protein, GRP78va is devoid of the ER signaling peptide and is cytosolic. Through specific knockdown of endogenous GRP78va by siRNA without affecting canonical GRP78, we showed that GRP78va promotes cell survival under ER stress. We further demonstrated that GRP78va has the ability to regulate PERK signaling and that GRP78va is able to interact with and antagonize PERK inhibitor P58(IPK). Our study describes the discovery of GRP78va, a novel cytosolic isoform of GRP78/BiP, and the first characterization of the modulation of UPR signaling via alternative splicing of nuclear pre-mRNA. Our study further reveals a novel survival mechanism in leukemic cells and other cell types where GRP78va is expressed.

Transcriptional induction of GRP78/BiP by histone deacetylase inhibitors and resistance to histone deacetylase inhibitor-induced apoptosis.

Histone deacetylase (HDAC) inhibitors are emerging as effective therapies in the treatment of cancer, and the role of HDACs in the regulation of promoters is rapidly expanding. GRP78/BiP is a stress inducible endoplasmic reticulum (ER) chaperone with antiapoptotic properties. We present here the mechanism for repression of the Grp78 promoter by HDAC1. Our studies reveal that HDAC inhibitors specifically induce GRP78, and the induction level is amplified by ER stress. Through mutational analysis, we have identified the minimal Grp78 promoter and specific elements responsible for HDAC-mediated repression. We show the involvement of HDAC1 in the negative regulation of the Grp78 promoter not only by its induction in the presence of the HDAC inhibitors trichostatin A and MS-275 but also by exogenous overexpression and small interfering RNA knockdown of specific HDACs. We present the results of chromatin immunoprecipitation analysis that reveals the binding of HDAC1 to the Grp78 promoter before, but not after, ER stress. Furthermore, overexpression of GRP78 confers resistance to HDAC inhibitor-induced apoptosis in cancer cells, and conversely, suppression of GRP78 sensitizes them to HDAC inhibitors. These results define HDAC inhibitors as new agents that up-regulate GRP78 without concomitantly inducing the ER or heat shock stress response, and suppression of GRP78 in tumors may provide a novel, adjunctive option to enhance anticancer therapies that use these compounds.

Endoplasmic reticulum stress.

Stress is the imbalance of homeostasis, which can be sensed even at the subcellular level. The stress-sensing capability of various organelles including the endoplasmic reticulum (ER) has been described. It has become evident that acute or prolonged ER stress plays an important role in many human diseases; especially those involving organs/tissues specialized in protein secretion. This article summarizes the emerging role of ER stress in diverse human pathophysiological conditions such as carcinogenesis and tumor progression, cerebral ischemia, plasma cell maturation and apoptosis, obesity, insulin resistance, and type 2 diabetes. Certain components of the ER stress response machinery are identified as biomarkers of the diseases or as possible targets for therapeutic intervention.

Vascular targeting and antiangiogenesis agents induce drug resistance effector GRP78 within the tumor microenvironment.

Therapeutic targeting of the tumor vasculature that destroys preexisting blood vessels of the tumor and antiangiogenesis therapy capitalize on the requirement of tumor cells on an intact vascular supply for oxygen and nutrients for growth, expansion and metastasis to the distal organs. Whereas these classes of agents show promise in delaying tumor progression, they also create glucose and oxygen deprivation conditions within the tumor that could trigger unintended prosurvival responses. The glucose-regulated protein GRP78, a major endoplasmic reticulum chaperone, is inducible by severe glucose depletion, anoxia, and acidosis. Here we report that in a xenograft model of human breast cancer, treatment with the vascular targeting agent, combretastatin A4P, or the antiangiogenic agent, contortrostatin, promotes transcriptional activation of the Grp78 promoter and elevation of GRP78 protein in surviving tumor cells. We further show that GRP78 is overexpressed in a panel of human breast cancer cells that has developed resistance to a variety of drug treatment regimens. Suppression of GRP78 through the use of lentiviral vector expressing small interfering RNA sensitizes human breast cancer cells to etoposide-mediated cell death. Our studies imply that antivascular and antiangiogenesis therapy that results in severe glucose and oxygen deprivation will induce GRP78 expression that could lead to drug resistance.

Endoplasmic reticulum stress induction of the Grp78/BiP promoter: activating mechanisms mediated by YY1 and its interactive chromatin modifiers.

The unfolded protein response is an evolutionarily conserved mechanism whereby cells respond to stress conditions that target the endoplasmic reticulum (ER). The transcriptional activation of the promoter of GRP78/BiP, a prosurvival ER chaperone, has been used extensively as an indicator of the onset of the UPR. YY1, a constitutively expressed multifunctional transcription factor, activates the Grp78 promoter only under ER stress conditions. Previously, in vivo footprinting analysis revealed that the YY1 binding site of the ER stress response element of the Grp78 promoter exhibits ER stress-induced changes in occupancy. Toward understanding the underlying mechanisms of these unique phenomena, we performed chromatin immunoprecipitation analyses, revealing that YY1 only occupies the Grp78 promoter upon ER stress and is mediated in part by the nuclear form of ATF6. We show that YY1 is an essential coactivator of ATF6 and uncover their specific interactive domains. Using small interfering RNA against YY1 and insertional mutation of the gene encoding ATF6alpha, we provide direct evidence that YY1 and ATF6 are required for optimal stress induction of Grp78. We also discovered enhancement of the ER-stressed induction of the Grp78 promoter through the interaction of YY1 with the arginine methyltransferase PRMT1 and evidence of its action through methylation of the arginine 3 residue on histone H4. Furthermore, we detected ER stress-induced binding of the histone acetyltransferase p300 to the Grp78 promoter and histone H4 acetylation. A model for the ER stress-mediated transcription factor binding and chromatin modifications at the Grp78 promoter leading to its activation is proposed.

Transcriptional regulation of the Grp78 promoter by endoplasmic reticulum stress: role of TFII-I and its tyrosine phosphorylation.

TFII-I is a signal-induced multi-functional transcription factor that has recently been implicated as a regulatory component of the endoplasmic reticulum (ER) stress response. TFII-I acts through ER stress-induced binding to the ER stress element, which is highly conserved in promoters of ER stress-inducible genes such as Grp78/BiP. Interestingly, its tyrosine phosphorylation sites are required for its activation of the Grp78 promoter. Toward understanding the link between TFII-I, the tyrosine kinase signaling pathway, and Grp78 activation, we discovered that Tg stress induces a dramatic increase of TFII-I phosphorylation at Tyr248 and localization of this form of TFII-I to the nucleus. Chromatin immunoprecipitation analysis further reveals enhanced TFII-I binding to the Grp78 promoter in vivo upon ER stress. Previously, we reported that genistein, a general inhibitor of tyrosine kinase, could suppress ER stress induction of Grp78 by inhibiting complex formation on the ER stress element; however, the mechanism is not known. Consistent with TFII-I being a target of genistein suppression, we observed that genistein could suppress Tg stress-induced phosphorylation of TFII-I. We further demonstrate that c-Src, which is one of kinases identified to mediate phosphorylation of TFII-I at Tyr248, is activated by Tg stress and is able to stimulate the Grp78 promoter activity. Lastly, using stable cell lines with suppressed TFII-I levels, we show that TFII-I is required for optimal induction of Grp78 by ER stress. Our studies provide a molecular link that connects the c-Src tyrosine kinase transduction pathway to ER stress-induced transcriptional activation of Grp78 mediated by TFII-I.

Underglycosylation of ATF6 as a novel sensing mechanism for activation of the unfolded protein response.

ATF6 is a key transcriptional activator of the unfolded protein response (UPR), which allows mammalian cells to maintain cellular homeostasis when they are subjected to a variety of environmental and physiological stresses that target the endoplasmic reticulum (ER). ATF6, a 90-kDa ER transmembrane protein, contains three evolutionarily conserved N-linked glycosylation sites within its carboxyl luminal domain. Although it is well established that p90ATF6 activation requires transit from the ER to the Golgi, where it is cleaved by the S1P/S2P protease system to generate a nuclear form p60ATF6 that acts as a transcriptional activator, the functional significance of p90ATF6 N-linked glycosylation is unknown. Here we show that ER Ca(2+) depletion stress, a triggering mechanism for the UPR, induces the formation of ATF6(f), which represents de novo partial glycosylation of newly synthesized p90ATF6. By mutating a single amino acid within the N-linked glycosylation site closest to the carboxyl terminus of p90ATF6, we recreated ATF6(f). This mutation sharply reduces p90ATF6 association with calreticulin, a major Ca(2+)-binding chaperone for N-glycoprotein. We further determined that ATF6(f) exhibits a faster rate of constitutive transport to the Golgi, resulting in a higher level of p60ATF6 in the nucleus and stronger transactivating activity in the absence of ER stress. Additional analysis of p90ATF6 mutants targeting single or multiple N-glycosylation sites also showed higher constitutive transactivating activity than wild type ATF6. Because accumulation of underglycosylated proteins in the ER is a potent inducer for the UPR, these studies uncover a novel mechanism whereby the glycosylation status of p90ATF6 can serve as a sensor for ER homeostasis, resulting in ATF6 activation to trigger the UPR.

Induction of Grp78/BiP by translational block: activation of the Grp78 promoter by ATF4 through and upstream ATF/CRE site independent of the endoplasmic reticulum stress elements.

Mammalian cells respond to endoplasmic reticulum (ER) stress by attenuation of protein translation mediated through the PERK-eIF2alpha pathway and transcriptional activation of genes such as Grp78/BiP encoding ER chaperone proteins. The disruption of PERK function or the blocking of eIF2alpha Ser51 phosphorylation fails to attenuate translation after ER stress and also results in substantial impairment of Grp78/BiP induction by ER stress. While the activation of the Grp78 promoter by the ATF6 pathway through the endoplasmic reticulum stress elements (ERSEs) is well documented, the molecular mechanism linking PERK activation to Grp78 stress induction is unknown. We report here that ATF4, a transcription factor whose translation is up-regulated by the PERK-eIF2alpha pathway, can activate the Grp78 promoter independent of the ERSE. The ATF4-activating site is localized to an ATF/CRE sequence upstream of the ERSEs and is distinct from the C/EBP-ATF composite site previously identified as the ATF4 binding site in the ER stress-inducible chop promoter. In vitro translated ATF4 binding to the ATF/CRE site requires other nuclear co-factors from non-stressed cells, forming a complex that exhibits identical electrophoretic mobility as a thapsigargin-stress induced complex. Here we have identified the closely related ATF1 and CREB1 as nuclear co-factors that form in vivo complexes with endogenous ATF4. ER stress induces CREB1 phosphorylation and ATF1/CREB1 binding to the Grp78 promoter. Through the use of adenoviral vector expression systems, we provide evidence that when ATF4 function is suppressed and its binding partners are not able to compensate for its function, Grp78 induction by Tg and Tu is partially inhibited. Our studies resolve a mechanism responsible for inhibition of Grp78 mRNA induction by ER stress in cells that are functionally null for PERK or devoid of eIF2alpha phosphorylation.

Endoplasmic reticulum chaperone protein GRP78 protects cells from apoptosis induced by topoisomerase inhibitors: role of ATP binding site in suppression of caspase-7 activation.

A large number of correlative studies have established that the activation of the unfolded protein response (UPR) alters the cell's sensitivity to chemotherapeutic agents. Although the induction of the glucose-regulated proteins (GRPs) is commonly used as an indicator for the UPR, the direct role of the GRPs in conferring resistance to DNA damaging agents has not been proven. We report here that without the use of endoplasmic reticulum (ER) stress inducers, specific overexpression of GRP78 results in reduced apoptosis and higher colony survival when challenged with topoisomerase II inhibitors, etoposide and doxorubicin, and topoisomerase I inhibitor, camptothecin. While investigating the mechanism for the GRP78 protective effect against etoposide-induced cell death, we discovered that in contrast to the UPR, GRP78 overexpression does not result in G1 arrest or depletion of topoisomerase II. Caspase-7, an executor caspase that is associated with the ER, is activated by etoposide. We show here that specific expression of GRP78 blocks caspase-7 activation by etoposide both in vivo and in vitro, and this effect can be reversed by addition of dATP in a cell-free system. Recently, it was reported that ectopically expressed GRP78 and caspases-7 and -12 form a complex, thus coupling ER stress to the cell death program. However, the mechanism of how GRP78, a presumably ER lumen protein, can regulate cytosolic effectors of apoptosis is not known. Here we provide evidence that a subpopulation of GRP78 can exist as an ER transmembrane protein, as well as co-localize with caspase-7, as confirmed by fluorescence microscopy. Co-immunoprecipitation studies further reveal endogenous GRP78 constitutively associates with procaspase-7 but not with procaspase-3. Lastly, a GRP78 mutant deleted of its ATP binding domain fails to bind procaspase-7 and loses its protective effect against etoposide-induced apoptosis.

Urinary lipid changes during the development of chemically-induced renal papillary necrosis: a study using mefenamic acid and N-phenylanthranilic acid.

Acute renal papillary necrosis (RPN) in animals is characterized by increased renal lipid accumulation. The excretion of renal lipids into urine has been determined to evaluate their possible use as sensitive early biomarkers for the diagnosis of RPN. This study investigates injury induced by two model nephrotoxins, mefenamic acid (MFA), a non-steroidal anti-inflammatory drug (NSAID), and its analogue N-phenylanthranilic acid (NPAA). Oral NPAA was given repeatedly at doses of 100, 250 and 500 mg kg(-1) daily for 5 days, followed by a 2 day respite over the weekend, and then four further daily doses. The same dosing procedure was used with MFA, but at doses of 75, 150 and 300 mgkg(-1). The control groups were given vehicle orally using the same volume given to the test groups. Urinary phospholipids (PLs), notably sphingomyelin (SPM), phosphatidylcholine (PC) and phosphatidylethanolamine (PE), were measured and compared with other urinary parameters. Histopathological investigations were also performed to confirm the presence or absence of RPN. Following MFA treatment, PC, PI and PE were raised significantly (p < 0.001) on days 1 and 3 and for the remaining part of the experiment. After NPAA treatment, PI showed a transient elevation, and PC and PE levels were significantly increased from day 2 onwards. Both drugs caused a dose-related increase in PLs. There was no significant increase in the level of other urinary parameters. However, histopathological examination of the kidney on day 11 revealed lesions in the medulla and papilla following treatment with the two papillotoxins. These findings demonstrate the potential of urinary PLs as diagnostic non-invasive biomarkers for early renal injury associated with RPN, which may provide an important improvement in the approach to the therapeutic management of analgesic nephropathy.