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PP01.34 Induction of Tertiary Lymphoid Structures in Non-Small Cell Lung Cancer Improves B and T Cell Anti-Tumor Immunity. J Thorac Oncol 2023. [DOI: 10.1016/j.jtho.2022.09.060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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The Impact of Land Tenure Security on a Livelihood Intervention for People Living with HIV in Western Kenya. AIDS Behav 2023; 27:245-256. [PMID: 35930199 PMCID: PMC9851924 DOI: 10.1007/s10461-022-03760-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/15/2022] [Indexed: 01/24/2023]
Abstract
Few studies have explored land access, a structural driver of health, and women's participation in livelihood interventions to improve food security and HIV outcomes. This qualitative study, embedded within Shamba Maisha (NCT02815579)-a randomized controlled trial (RCT) examining the impact of a multisectoral intervention among farmers living with HIV in western Kenya-sought to explore the influence of perceived access to and control of land on agricultural productivity, investments, and benefits. Thirty in-depth interviews (IDIs) were conducted with purposively sampled men and women, 3 to 6 months after receiving intervention inputs; data were deductively and inductively coded and analyzed. Farming practices and participation in Shamba Maisha were dependent on land tenure and participants' perceived strength of claim over their land, with participants who perceived themselves to be land insecure less likely to make long-term agricultural investments. Land tenure was influenced by a number of factors and posed unique challenges for women which negatively impacted uptake and success in the intervention. Data underscore the importance of secure land tenure for the success of similar interventions, especially for women; future interventions should integrate land security programming for improved outcomes for all.
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81 IMPROVING THE ASSESSMENT AND PREVENTION OF FALLS AND FRACTURES ON A REHABILITATION WARD. Age Ageing 2022. [DOI: 10.1093/ageing/afac218.066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
The National Steering Group and The National Institute for Health and Care Excellence provide guidelines on medical assessment and prevention of falls and fractures. This audit assesses and compares quality of practice on an Age-Related rehabilitation ward against these guidelines.
Methods
A retrospective audit, including all patients (n=31) on an off-site, Age-Related rehabilitation ward was completed. Data on falls and fractures at emergency department presentation and during admission was obtained through chart review. Following education and implementation of a falls pro-forma, a re-audit was completed at four months including all patients (n=40).
Results
In cycle 1, mean age of patients was 80 years (range 56-94), 39 Percent (%) (n=12) were admitted with a fall of whom 66.7% (n=8) had a resulting fracture. In cycle 2, mean age was 82 years (range 63–95), 48% (n=19) were admitted due to a fall, of whom 53% (n=10) had a fracture.
A falls assessment and bone health review was completed in 39% (n=12) of all patients in cycle 1, and in 37% (n=3) admitted with a fall. This increased to 83% (n=33) of all patients in cycle 2 and 100% (n=40) of those admitted with a fall. Pre-intervention, 23% (n=7) had an inpatient fall compared to 18% (n=7) post-intervention; of these, 43% (n=3) and 14% (n=1) resulted in fractures respectively.
Conclusion
Compliance with national guidelines for prevention of falls and fractures improved with education and implementation of a falls pro-forma. This resulted in a reduction in falls, particularly injurious falls, on a rehabilitation ward. In future, this pro-forma may be implemented in other hospital wards.
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Treatment Challenges When Stopping Denosumab. IRISH MEDICAL JOURNAL 2022; 115:567. [PMID: 35532944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Introduction Denosumab is commonly used to treat osteoporosis. However, discontinuation results in rebound bone loss and increased vertebral fracture risk. We report a clinical case series, illustrating the dilemma in deciding the best treatment should denosumab be stopped. Cases In eight patients aged 56-89 years, zolendronic acid after stopping denosumab resulted in BTM rises and BMD decline. In a 68-year-old, two years of oral bisphosphonate after three years of denosumab resulted in elevated bone turnover markers (BTM) and decline in bone mineral density (BMD), necessitating a switch to zoledronic acid. In a 79-year-old, two annual doses of zolendronic acid after three years of denosumab failed to suppress high BTM, with BMD dropping and denosumab being restarted. In a 60-year-old, on stopping denosumab after 10 years of oral bisphosphonate, BMD remained stable despite no further therapy. Conclusion Drug holidays are not an option with denosumab, with a risk of bone loss even on transitioning to bisphosphonates. Risk is greater with longer duration of treatment6 and may be mitigated by prior bisphosphonate use. Standard dose zoledronic acid does not prevent bone loss in a significant proportion of patients. BTM may help in monitoring treatment and need for further bisphosphonates.
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Distal radius manipulation under anesthetic can be safely performed by advanced practice physiotherapists in the emergency department. Physiotherapy 2022. [DOI: 10.1016/j.physio.2021.12.091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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A physiotherapy led minor injuries unit during the covid pandemic. Physiotherapy 2022. [DOI: 10.1016/j.physio.2021.12.078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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"When I Eat Well, I Will Be Healthy, and the Child Will Also Be Healthy": Maternal Nutrition among HIV-Infected Women Enrolled in a Livelihood Intervention in Western Kenya. Curr Dev Nutr 2020; 4:nzaa032. [PMID: 32270133 PMCID: PMC7127924 DOI: 10.1093/cdn/nzaa032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 03/03/2020] [Accepted: 03/03/2020] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Food insecurity remains a major obstacle to achieving health and well-being for individuals living with HIV in western Kenya. Studies have shown that pregnant women are vulnerable to experiencing food insecurity worldwide, with significant consequences for both maternal and child health. The Shamba Maisha cluster randomized controlled trial in western Kenya (which means "farming for life" in Swahili) tested the effects of a multisectoral livelihood intervention consisting of agricultural and finance trainings, farm inputs, and a loan on health and food security among 746 farmers living with HIV in Kisumu, Homa Bay, and Migori Counties. OBJECTIVES We conducted a qualitative substudy within the Shamba Maisha trial to understand the experiences and perspectives of pregnant women living with HIV enrolled in the trial. METHODS Thirty women who had experienced a pregnancy during the Shamba Maisha study period, comprising 20 women in the intervention arm and 10 women in the control arm, completed in-depth interviews using a semistructured interview guide. RESULTS Intervention participants interviewed noted improvements in maternal nutrition compared with previous pregnancies, which they attributed to the livelihood intervention. Key identified pathways to improved nutrition included improved access to vegetables, increased variety of diet through vegetable sales, and improved nutritional awareness. Women in the intervention arm also perceived increased weight gain compared with prior pregnancies and increased strength and energy throughout pregnancy. CONCLUSIONS Livelihood interventions represent a promising solution to alleviate food insecurity for pregnant women in order to improve maternal and child health outcomes.This trial was registered at clinicaltrials.gov as NCT02815579.
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Abstract
The nucleus basalis (NB) is a cholinergic neuromodulatory structure that projects liberally to the entire cortical mantle and regulates information processing in all cortical layers. Here, we recorded activity from populations of single units in the NB as rats performed a whisker-dependent tactile discrimination task. Over 80% of neurons responded with significant modulation in at least one phase of the task. Such activity started before stimulus onset and continued for seconds after reward delivery. Firing rates monotonically increased with reward magnitude during the task, suggesting that NB neurons are not indicating the absolute deviation from expected reward amounts. Individual neurons also encoded significant amounts of information about stimulus identity. Such robust coding was not present when the same stimuli were delivered to lightly anesthetized animals, suggesting that the NB neurons contain a sensorimotor, rather than purely sensory or motor, representation of the environment. Overall, these results support the hypothesis that neurons in the NB provide a value-laden representation of the sensorimotor state of the animal as it engages in significant behavioral tasks.
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Compression injury in the mouse spinal cord elicits a specific proliferative response and distinct cell fate acquisition along rostro-caudal and dorso-ventral axes. Neuroscience 2013; 254:1-17. [DOI: 10.1016/j.neuroscience.2013.09.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2013] [Revised: 09/01/2013] [Accepted: 09/04/2013] [Indexed: 12/14/2022]
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8. Health status, health-related quality of life and psychological state in patients with pulmonary arterial hypertension. Heart Lung 2011. [DOI: 10.1016/j.hrtlng.2011.04.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Rationale and design of CAPITA: a RCT of 13-valent conjugated pneumococcal vaccine efficacy among older adults. Neth J Med 2008; 66:378-383. [PMID: 18990781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The burden of community-acquired pneumonia (CAP) among the elderly is high and has increased over the last decades. Streptococcus pneumoniae is the most common cause of CAP and in 10% the infection may be fatal. Although the 23-valent polysaccharide pneumococcal vaccine (23vPS) is considered effective in the prevention of invasive pneumococcal disease in the elderly population, the evidence is mainly from nonrandomised observational studies and effects on the occurrence of pneumonia have not been demonstrated. Conjugated pneumococcal vaccines which also stimulate T-cell dependent immune responses induced antibody responses in elderly persons which are similar to those induced by a primary series of 7-valent conjugated pneumococcal vaccine (7vPnC) in infants, and the response appeared similar or superior for all vaccine serotypes to that induced by 23vPS. The primary objective of the planned trial entitled CAPITA (Community Acquired Pneumonia Immunization Trial in Adults) is to establish the efficacy of a 13-valent PnC vaccine in the prevention of a first episode of vaccine-serotype specific pneumococcal CAP in 85,000 community-dwelling adult persons aged 65 years and older. This is a parallel group, randomised, placebo-controlled trial, with a 1:1 random allocation to vaccine or placebo vaccine. The occurrence of the primary outcome of vaccine-serotype specific (VT)-CAP will be established in hospitals on the basis of three sets of criteria: (1) a clinical definition of CAP; (2) independent interpretation of chest radiograph consistent with pneumonia: and (3) determination of S. pneumonia serotype. the trial will be critical to determine the position of conjugate pneumococcal vaccines in the prevention of pneumococcal disease.
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Inhibition of ganciclovir-susceptible and -resistant human cytomegalovirus clinical isolates by the benzimidazole L-riboside 1263W94. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 2001; 8:1279-81. [PMID: 11687477 PMCID: PMC96263 DOI: 10.1128/cdli.8.6.1279-1281.2001] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The average 50% inhibitory concentration (IC(50)) values for AD169 were 0.22 +/- 0.09 microM 1263W94 and 5.36 +/- 0.12 microM ganciclovir. For 35 human cytomegalovirus (HCMV) clinical isolates the average IC(50) was 0.42 +/- 0.09 microM 1263W94, and for 26 ganciclovir-susceptible HCMV clinical isolates the average IC(50) was 3.78 +/- 1.62 microM ganciclovir. Nine HCMV clinical isolates that were resistant to ganciclovir were completely susceptible to 1263W94.
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Susceptibilities of human cytomegalovirus clinical isolates to BAY38-4766, BAY43-9695, and ganciclovir. Antimicrob Agents Chemother 2001; 45:2925-7. [PMID: 11557492 PMCID: PMC90754 DOI: 10.1128/aac.45.10.2925-2927.2001] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
BAY38-4766 and BAY43-9695 are nonnucleosidic compounds with activities against human cytomegalovirus (HCMV). Two phenotypic assays were used to determine the drug susceptibilities of 36 HCMV clinical isolates to the BAY compounds and ganciclovir. Using either assay, both BAY compounds at a concentration of approximately 1 microM inhibited the replication of all 36 HCMV clinical isolates, including 11 ganciclovir-resistant clinical isolates, by 50%.
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Long-time behavior of the velocity autocorrelation function for moderately dense, soft-repulsive, and Lennard-Jones fluids. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2001; 63:026109. [PMID: 11308544 DOI: 10.1103/physreve.63.026109] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/1999] [Revised: 07/27/2000] [Indexed: 05/23/2023]
Abstract
The long-time behavior of the velocity autocorrelation function (VAF), for hard disk and sphere systems, has been extensively explored. Its behavior for systems interacting via a soft repulsive or attractive potential is less well known. We explore the conditions under which the nonexponential, long-time tail in the velocity autocorrelation function of a tagged atom, in soft-repulsive sphere (Weeks-Chandler-Andersen) and Lennard-Jones atomic fluids, may be readily observed by the molecular dynamics method. The effect of changing the system size, the fluid density, the form of the interatomic force and the mass of the tagged atoms are investigated. We were able to observe this long-time tail only for systems of moderate density. At low density the effect, if it exists, is at longer times than we can currently simulate owing to limitations of system size and at higher densities these tails were not observed possibly due to other effects dominating the behavior of the VAF and masking this behavior. Under the physical conditions that are simulated here attractive forces have very little effect on the behavior of the VAF. However, as the mass of the tagged particles is increased the time at which the long-time tail commences is lengthened and its magnitude is significantly increased. This later effect suggests that by increasing the mass of the tagged particles one may be able to study more readily the behavior, nature and physical origin of long-time behavior of the VAF both by computational and by experimental techniques.
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Abstract
The British Universities Human Embryo Database has been created by merging information from the Walmsley Collection of Human Embryos at the School of Biological and Medical Sciences, University of St Andrews and from the Boyd Collection of Human Embryos at the Department of Anatomy, University of Cambridge. The database has been made available electronically on the Internet and World Wide Web browsers can be used to implement interactive access to the information stored in the British Universities Human Embryo Database. The database can, therefore, be accessed and searched from remote sites and specific embryos can be identified in terms of their location, age, developmental stage, plane of section, staining technique, and other parameters. It is intended to add information from other similar collections in the UK as it becomes available.
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Differential expression of Na,K-ATPase alpha and beta subunit isoforms at the blood-brain barrier and the choroid plexus. J Biol Chem 1993; 268:8019-25. [PMID: 8385133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The relative levels of expression of Na,K-ATPase alpha and beta subunit isoforms were determined in rat cerebral microvessels, choroid plexus, and capillary-depleted brain homogenates by Western blot analysis. Three alpha (alpha 1, alpha 2, alpha 3) and two beta (beta 1, beta 2) subunits were detected in brain as previously reported. All 3 alpha and 2 beta isoforms were also found in microvessels. The choroid plexus expressed alpha 1, beta 1, and beta 2, while alpha 2 and alpha 3 were not found. Autoradiographic signals were normalized to a constant amount of protein from the 3 tissues to calculate relative levels of expression. Expression of alpha 1, alpha 2, and alpha 3 was higher in microvessels than in the brain, by 1.7-, 1.2-, and 1.2-fold, respectively, but expression of beta 1 and beta 2 was 5.5-fold lower. alpha 1 was 4-fold higher in the choroid plexus than in the brain, while expression of beta 1 and beta 2 was 15- and 5.5-fold lower, respectively. Na,K-ATPase enzymatic activities in microvessels and choroid plexus homogenates were similar and 5-fold lower than in brain homogenate. We conclude that: (a) expression of functionally active Na,K-ATPase isoenzymes in microvessels and choroid plexus is restricted in comparison to the brain possibly due to a limited pool of beta 1 and beta 2 subunits; (b) six structurally distinct Na,K-ATPase isoenzymes may be expressed in cerebral microvessels and two in the choroid plexus.
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Expression of Na,K-ATPase at the blood-brain interface. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1993; 331:55-60. [PMID: 8392783 DOI: 10.1007/978-1-4615-2920-0_9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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Abstract
Chronic lead exposure may cause hypertension in normotensive rats. This hypertensinogenic effect has been attributed to perturbations in the renin-angiotensin axis, the contractile response of the vascular smooth muscle, or the intracellular Ca2+ homeostasis as a consequence of the inhibition of Na(+)-K(+)-ATPase activity. In this study we examined the short-term effect of lead exposure on blood pressure, plasma renin activity, vascular contractility, and renal Na(+)-K(+)-ATPase activity and abundance in the spontaneously hypertensive rat. Our data indicate that modest lead exposure caused blood pressure elevation within two weeks in this rat strain that is genetically susceptible to the development of hypertension. This rapid blood pressure-elevating effect did not appear to depend on the mechanisms described in hypertension associated with more chronic lead exposure listed above. This acute model provides an additional approach to the study of lead-induced hypertension.
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Regulation of testicular P-450 cholesterol side-chain cleavage and P-450 C17-20 lyase/C17 hydroxylase enzymes in the neonatal and adult rat. ACTA ENDOCRINOLOGICA 1991; 124:449-54. [PMID: 2031442 DOI: 10.1530/acta.0.1240449] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Adult Leydig cells respond to LH or hCG with an initial stimulation of testosterone secretion followed by LH receptor down-regulation and blockade of androgen biosynthesis. In contrast, fetal Leydig cells respond with increased LH receptor number and enhanced steroidogenesis. In this study, the molecular mechanisms of high-dose hCG treatment on steroidogenesis in adult and neonatal testes (containing predominantly the fetal generation of Leydig cells) were examined using two recombinant DNA clones specific for enzymes of the rat steroidogenic pathway (P-450 cholesterol side-chain cleavage enzyme, P-450scc and P-450 17 alpha-hydroxylase/C17-20 lyase, P-450c17). We treated adult (60 days of age) and neonatal (2 days of age) rats with a single high dose of hCG (600 IU/kg), sc. The high dose of hCG caused neonatal testicular P450scc and P450c17 mRNA levels to increase, and stimulated adult testicular P450scc mRNA levels, but caused a decrease in adult P450c17 mRNA levels. These studies suggest that high doses of hCG regulate testosterone production differently in adult and fetal Leydig cells at a pretranslational level of the P450c17 enzyme, while mRNA for P450scc is stimulated in both the adult and fetal Leydig cell.
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PRO use of Medicare data. JOURNAL OF QUALITY ASSURANCE : A PUBLICATION OF THE NATIONAL ASSOCIATION OF QUALITY ASSURANCE PROFESSIONALS 1990; 12:8-11, 48. [PMID: 10106823 DOI: 10.1111/j.1945-1474.1990.tb00054.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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alar4, a constitutive mutant of the A system for amino acid transport, has increased abundance of the Na+,K+-ATPase and mRNA for alpha 1 subunit of this enzyme. Proc Natl Acad Sci U S A 1989; 86:7984-8. [PMID: 2554299 PMCID: PMC298197 DOI: 10.1073/pnas.86.20.7984] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
A constitutive mutant, alar4, for the A system of amino acid transport, has increased activity and amount of the A system. This is accompanied by increased sensitivity to ouabain, as measured by efficiency of plating, and increased activity and abundance of the Na+,K+-ATPase that is present in the parental cell line, CHO-K1 (wild type). The latter was shown by increases in (i) ouabain-inhibitable 86Rb uptake in intact cells, (ii) ouabain-inhibitable ATPase activity in mixed membrane vesicles, and (iii) number of ouabain-binding sites and by similar Kd values for ouabain binding and K1/2 for ouabain inhibition of Na+,K+-ATPase as compared to the wild type. The increase in abundance of the Na+ pump is associated with a 4-fold increase in abundance of the mRNA for the alpha 1 subunit of the Na+,K+-ATPase. We could not detect mRNA for alpha 2 or alpha 3 or for the beta subunits. The increase in abundance of the A system and Na+,K+-ATPase is associated with a negligible increase in intracellular Na+ concentration. We propose that the increase in the abundance of the A system and the Na+,K+-ATPase is the result of a mutation in regulatory gene R1 that controls the A system and the Na+,K+-ATPase and is not due to a primary effect of a possible initial increase in Na+ concentration.
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Patterns of mRNA expression during early cell growth differ in kidney epithelial cells destined to undergo compensatory hypertrophy versus regenerative hyperplasia. Proc Natl Acad Sci U S A 1988; 85:6768-72. [PMID: 3413124 PMCID: PMC282059 DOI: 10.1073/pnas.85.18.6768] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
An increase in cell size and protein content is characteristic of cells undergoing hypertrophy and of replicating cells prior to DNA synthesis. Cell enlargement in the two situations could be regulated by similar early events with an interruption of the cell cycle occurring in hypertrophy, or the two processes could be uncoupled. In vivo models were used to compare hypertrophy induced by unilateral nephrectomy and hyperplasia induced by folic acid injection in rabbit renal cortical cells. Within 48 hr, cell volume increased in both groups but the number of cells in the cell cycle and DNA synthesis was increased only after folic acid. Patterns of mRNA expression of the following three groups of cell cycle-dependent genes were analyzed: (i) protooncogenes (c-fos, c-myc, and c-Ha-ras), (ii) structural protein genes (vimentin and beta-actin), and (iii) transport protein genes (Na+, K+-ATPase, ADP-ATP translocase, and calcyclin). mRNAs for all genes, except calcyclin and c-Ha-ras, were detected in controls. Folic acid generally induced rapid, transient increases in mRNA levels, but after unilateral nephrectomy, expression of most mRNAs showed a gradual, progressive increase. These data indicate that gene expression in the early stages of cell enlargement differs in cells destined to undergo proliferation vs. hypertrophy. The term "sustained message amplification" is proposed to describe the hypertrophied cell.
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Pretranslational regulation of Na-K-ATPase in cultured canine kidney cells by low K+. THE AMERICAN JOURNAL OF PHYSIOLOGY 1987; 252:C179-89. [PMID: 3030119 DOI: 10.1152/ajpcell.1987.252.2.c179] [Citation(s) in RCA: 72] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Long-term upregulation of the sodium pump [Na-K-adenosine triphosphatase (Na-K-ATPase)] entails an increase in the number of enzyme molecules. We incubated Madin-Darby canine kidney (MDCK) cells in low K+ medium and studied the time course and magnitude of change in the relative abundance of the two Na-K-ATPase subunits (alpha and beta), in the synthesis rate of the subunits, and in the relative abundance of alpha- and beta-mRNA. When cells were incubated in medium containing 0.25 mM K+, intracellular Na+ increased from 25.2 +/- 0.9 (SE) mmol/l cell H2O to 69.8 +/- 9.6 at 4 h and 132 +/- 6 at 16 h. Cell K+ fell from 146 +/- 4 mmol/l cell H2O to 105 +/- 9 at 4 h and 42.3 +/- 4.7 at 16 h. The relative abundance of Na-K-ATPase subunits, measured with immunoblots of cell homogenates, increased such that after 24 h alpha was 1.71 +/- 0.33 and beta was 1.67 +/- 0.22 times control. After 8 h of K+ depletion, alpha-synthesis rate, measured by immunoprecipitation of pulse-labeled cells, increased to 2.30 +/- 0.50 and beta increased to 2.07 +/- 0.42 times control. The alpha- and beta-subunit mRNA abundance, measured by hybridizing alpha- and beta-cDNA probes to total RNA, increased within 30 min to 1.93 +/- 0.24 and 2.29 +/- 0.64 times control, respectively. We conclude that regulatory adjustments of Na-K-ATPase abundance involve an increase in translation after a rapid and coordinate increase in the concentrations of alpha- and beta-subunit mRNA.
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Abstract
cDNA clones for the rat liver and muscle glycogen phosphorylase isozymes have been isolated using isozyme-selective antibodies and libraries prepared in the expression vector, lambda gt11. A 1.2 kb cDNA coding for the carboxy-terminal domain of rat liver phosphorylase was found to have 82% homology with the amino acid sequence of rabbit muscle phosphorylase. Limited sequencing of rat muscle phosphorylase cDNA indicated a 95% homology with the rabbit muscle enzyme. The rat liver clone has eight additional amino acid residues at the COOH-terminus compared to the rat muscle clone. Furthermore, 17 of 26 (65%) residues between amino acids 815-840 differ between liver and muscle isozymes. The similarity in enzymatic properties and conservation of structure except at the COOH-terminus suggest that the liver and muscle phosphorylase isozymes do not exist in order to have significant differences in the regulation of glycogen breakdown in the two tissues. Rather, the phosphorylase isozymes probably evolved for tissue-specific transcriptional regulation of the genes in liver and muscle.
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Abstract
Na,K-ATPase was detected in crude microsomes of guinea-pig retinal layers, cornea and lens by immunoblotting using antibodies generated against purified kidney Na,K-ATPase. The antiserum cross-reacted with the alpha catalytic subunit of the enzyme from the eye tissues but not the beta glycoprotein subunit, suggesting a high degree of tissue-to-tissue variability in the beta subunit. The apparent molecular weight of the alpha subunit in retinal layers, cornea and lens was 95 Kd which is similar to alpha subunit in kidney. In the retinal layers and cornea, the antiserum detected proteolytic fragments of the enzyme. This method can be used to detect aggregates or proteolytic fragments of Na,K-ATPase in disease states of eye tissues in which electrolyte imbalances have been implicated, such as in experimental and senile cataracts.
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Comparison of subunits of cardiac, brain, and kidney Na+-K+-ATPase. THE AMERICAN JOURNAL OF PHYSIOLOGY 1985; 248:C247-51. [PMID: 2983564 DOI: 10.1152/ajpcell.1985.248.3.c247] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Na+-K+-ATPase is in low abundance in cardiac tissue. Therefore, we utilized antibodies to detect the cardiac Na+-K+-ATPase subunits and to compare their characteristics with those of kidney and brain Na+-K+-ATPase subunits. By using crude preparations of heart membranes as well as purified sarcolemmal membranes from guinea pig hearts, we resolved peptides by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, blotted them onto diazotized paper, and detected Na+-K+-ATPase subunits with antibodies generated against highly purified kidney Na+-K+-ATPase holoenzyme. We tested the hypothesis that the two families of ouabain-binding affinities described in heart are due to two forms of alpha-subunit, analogous to the two forms with different affinities for ouabain described in brain. Although the antibodies did detect two forms of catalytic subunit in brain (alpha and alpha +), only one form of alpha was detected in the heart membranes, with the same electrophoretic mobility as kidney alpha. Cardiac beta-subunit could also be detected with the antikidney antibodies. It had a similar electrophoretic mobility to that described for kidney beta, whereas brain beta had a higher mobility.
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