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Billington EO, Bristow SM, Gamble GD, de Kwant JA, Stewart A, Mihov BV, Horne AM, Reid IR. Acute effects of calcium supplements on blood pressure: randomised, crossover trial in postmenopausal women. Osteoporos Int 2017; 28:119-125. [PMID: 27543500 DOI: 10.1007/s00198-016-3744-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 08/12/2016] [Indexed: 12/17/2022]
Abstract
UNLABELLED Calcium supplements appear to increase cardiovascular risk, but the mechanism is unknown. We investigated the acute effects of calcium supplements on blood pressure in postmenopausal women. The reduction in systolic blood pressure was smaller after calcium compared with the placebo in the hours following dosing. INTRODUCTION Calcium supplements appear to be associated with increased cardiovascular risk; however, the mechanism of this is uncertain. We previously reported that blood pressure declined over a day in older women, and that this reduction was smaller following a calcium supplement. To confirm this finding, we investigated the acute effects of calcium supplements on blood pressure. METHODS This was a randomised controlled crossover trial in 40 healthy postmenopausal women (mean age 71 years and BMI 27.2 kg/m2). Women attended on two occasions, with visits separated by ≥7 days. At each visit, they received either 1 g of calcium as citrate, or placebo. Blood pressure and serum calcium concentrations were measured immediately before, and 2, 4 and 6 h after each intervention. RESULTS Ionised and total calcium concentrations increased after calcium (p < 0.0001 versus placebo). Systolic blood pressure decreased after both calcium and placebo, but significantly less so after calcium (p = 0.02). The reduction in systolic blood pressure from baseline was smaller after calcium compared with placebo by 6 mmHg at 4 h (p = 0.036) and by 9 mmHg at 6 h (p = 0.002). The reduction in diastolic blood pressure was similar after calcium and placebo. CONCLUSIONS These findings are consistent with those of our previous trial and indicate that the use of calcium supplements in postmenopausal women attenuates the post-breakfast reduction in systolic blood pressure by around 6-9 mmHg. Whether these changes in blood pressure influence cardiovascular risk requires further study.
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Mon W, Stewart A, Fernando R, Ashpole K, El-Wahab N, MacDonald S, Tamilselvan P, Columb M, Liu YM. Cardiac output changes with phenylephrine and ephedrine infusions during spinal anesthesia for cesarean section: A randomized, double-blind trial. J Clin Anesth 2016; 37:43-48. [PMID: 28235526 DOI: 10.1016/j.jclinane.2016.11.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 10/14/2016] [Accepted: 11/03/2016] [Indexed: 12/13/2022]
Abstract
Hypotension is a common side effect of spinal anesthesia. Phenylephrine and ephedrine are the two most frequently used vasopressors to treat spinal hypotension during cesarean delivery. In this randomized double-blind study, we aimed to evaluate cardiac output (CO) changes with phenylephrine or ephedrine infusions titrated to maintain baseline systolic blood pressure (bSBP) during spinal anesthesia. Women (n = 40) scheduled for elective cesarean delivery received either phenylephrine 100 μg/min or ephedrine 5 mg/min infusions. Baseline hemodynamics (cardiac output, heart rate, systolic blood pressure) were recorded in the left lateral tilt position before fluid preload, and recorded every minute after spinal anesthesia until delivery. Umbilical cord blood gases were analyzed within 5 minutes of delivery. Good systolic blood pressure control was attained in both groups with minimal periods of hypotension (SBP <80% of bSBP) or hypertension (SBP >120% of bSBP). Cardiac output and heart rate increased over time with ephedrine, but decreased with phenylephrine. The maximum increase in CO from the baseline was 12%, in the ephedrine group, and this occurred 20 minutes after spinal injection. Cardiac output fell by more than 17% in the phenylephrine group, maximal at 10 minutes following spinal injection. Despite good systolic blood pressure control and increased cardiac output with ephedrine, administration of ephedrine was associated with significantly more fetal acidosis [Median (Interquartile range, IQR) UApH - phenylephrine = 7.33 (7.31-7.34) and ephedrine = 7.22 (7.16-7.27), P < .05].
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Garland J, Warren G, Drasher M, Dierberg K, Gottesfeld J, Hann K, Stewart A, Kanu A, Bangura J, Bangura S. Employing survivors of Ebola virus disease (EVD) as a novel system to support community-based surveillance in an Ebola hotspot within Sierra Leone. Int J Infect Dis 2016. [DOI: 10.1016/j.ijid.2016.11.283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Skinner M, McMeeken J, Stewart A, de Caro JX, Sykes C. Raising the standard of physiotherapy education worldwide: WCPT's accreditation service. Physiotherapy 2016. [DOI: 10.1016/j.physio.2016.10.034] [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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Barkati M, King B, Fortin I, Portelance L, Viswanathan A, Fyles T, Beriwal S, Alfieri J, Lim K, Harkenrider M, Small W, Klopp A, Stewart A, Yashar C, Bosch W, Jhingran A, Jolicoeur M, Gaffney D. Intensity Modulated Radiation Therapy for Vulvar Carcinoma: Changes in Practice Over 5 Years. Int J Radiat Oncol Biol Phys 2016. [DOI: 10.1016/j.ijrobp.2016.06.1367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Stewart A, Krupnick R, Meyer M, Paty J, Hamed A. Late-onset Pompe disease signs and impacts: A conceptual model. Neuromuscul Disord 2016. [DOI: 10.1016/j.nmd.2016.06.091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Grant CC, Crane J, Mitchell EA, Sinclair J, Stewart A, Milne T, Knight J, Gilchrist C, Camargo CA. Vitamin D supplementation during pregnancy and infancy reduces aeroallergen sensitization: a randomized controlled trial. Allergy 2016; 71:1325-34. [PMID: 27060679 DOI: 10.1111/all.12909] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/04/2016] [Indexed: 02/06/2023]
Abstract
BACKGROUND Vitamin D has immune-modulating effects. We determined whether vitamin D supplementation during pregnancy and infancy prevents aeroallergen sensitization and primary care respiratory illness presentations. METHODS A randomized, double-blind, placebo-controlled parallel-group trial. We assigned pregnant women, from 27-week gestation to birth, and then their infants, from birth to 6 months, to placebo or one of two dosages of daily oral vitamin D. Woman/infant pairs were randomized to: placebo/placebo, 1000 IU/400 IU or 2000 IU/800 IU. When the children were 18 months old, we measured serum-specific IgE antibodies and identified acute primary care visits described by the doctor to be due to a cold, otitis media, an upper respiratory infection, croup, asthma, bronchitis, bronchiolitis, a wheezy lower respiratory infection or fever and cough. RESULTS Specific IgE was measured on 185 of 260 (71%) enrolled children. The proportion of children sensitized differed by study group for four mite antigens: Dermatophagoides farinae (Der-f1, Der-f2) and Dermatophagoides pteronyssinus (Der-p1, Der-p2). With results presented for placebo, lower dose, and higher dose vitamin D, respectively (all P < 0.05): Der-f1 (18%, 10%, 2%), Der-f2 (14%, 3%, 2%), Der-p1 (19%, 14%, 3%) and Der-p2 (12%, 2%, 3%). There were study group differences in the proportion of children with primary care visits described by the doctor as being for asthma (11%, 0%, 4%, P = 0.002), but not for the other respiratory diagnoses. CONCLUSIONS Vitamin D supplementation during pregnancy and infancy reduces the proportion of children sensitized to mites at age 18 months. Preliminary data indicate a possible effect on primary care visits where asthma is diagnosed.
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Zieleskiewicz L, Boghossian M, Delmas A, Jay L, Bourgoin A, Carcopino X, Poirier M, Cogniat B, Stewart A, Chassard D, Leone M, Bouvet L. Ultrasonographic measurement of antral area for estimating gastric fluid volume in parturients. Br J Anaesth 2016; 117:198-205. [DOI: 10.1093/bja/aew171] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/11/2016] [Indexed: 11/14/2022] Open
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Mongero LB, Beck JR, Charette KA, Stewart A. Respiratory failure of two sp gastric bypass patients and subsequent rescue with extracorporeal membrane oxygenation. Perfusion 2016; 21:73-6. [PMID: 16485703 DOI: 10.1191/0267659106pf837oa] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Severe obesity is a chronic condition that is difficult to treat through diet and exercise alone. Gastrointestinal surgery for obesity (bariatric surgery) alters the digestive process by either restrictive surgical alterations or malabsorptive operations. Some 10 - 20% of patients who have weight-loss surgery require follow-up operations to correct complications. Hypoxemia after gastric bypass surgery for morbid obesity, a reported complication, can occur as early as 24 h post surgery.Two patients presented with severe hypoxia and were placed on veno-venous extracorporeal membrane oxygenation (ECMO). Patient No. 1 had an obstruction of the alimentary limb of the gastric bypass due to suture adhesions, and patient No. 2 had an incarcerated diaphragmatic hernia. While on ECMO, ventilation using a protective strategy (60% FiO2, pressure-controlled ventilation inspiratory pressure (PCV) IP 25-27, positive end-expiratory pressure (PEEP) 10-14, permissive hyper-capnia) was employed. An inflow cannula to the level of the right atrium served as arterial outflow from the circuit to the patient, while the femoral vein served as venous inflow to the ECMO circuit.Although ECMO in adult respiratory failure is often used as the last resort due to serious associated adverse events, we report two patients with life-threatening complications from gastric bypass who were rescued, resuscitated to day 7, and uneventfully discharged from the hospital to home.
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Cummings NJ, Ambrose A, Braithwaite M, Bissett J, Roslan HA, Abdullah J, Stewart A, Agbayani FV, Steyaert J, Hill RA. Diversity of root-endophytic Trichoderma from Malaysian Borneo. Mycol Prog 2016. [DOI: 10.1007/s11557-016-1192-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Toplis P, Wellock IJ, Stewart A, Bailey M, Salmon L. 249 High lactose pellets fed from 4 d of age convey lifetime benefits when compared to a standard pre-weaning diet. J Anim Sci 2016. [DOI: 10.2527/msasas2016-249] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Lippmann Q, Stewart A, Tan-Kim J. 67: Voiding dysfunction and lower urinary tract symptoms after native tissue versus graft-augmented vaginal prolapse repair. Am J Obstet Gynecol 2016. [DOI: 10.1016/j.ajog.2016.01.098] [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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Bristow SM, Gamble GD, Pasch A, O'Neill WC, Stewart A, Horne AM, Reid IR. Acute and 3-month effects of calcium carbonate on the calcification propensity of serum and regulators of vascular calcification: secondary analysis of a randomized controlled trial. Osteoporos Int 2016; 27:1209-1216. [PMID: 26493812 DOI: 10.1007/s00198-015-3372-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2015] [Accepted: 10/13/2015] [Indexed: 12/30/2022]
Abstract
SUMMARY Calcium supplements have been associated with increased cardiovascular risk, but the mechanism is unknown. We investigated the effects of calcium supplements on the propensity of serum to calcify, based on the transition time of primary to secondary calciprotein particles (T50). Changes in serum calcium were related to changes in T50. INTRODUCTION Calcium supplements have been associated with increased cardiovascular risk; however, it is unknown whether this is related to an increase in vascular calcification. METHODS We investigated the acute and 3-month effects of calcium supplements on the propensity of serum to calcify, based on the transition time of primary to secondary calciprotein particles (T50), and on three possible regulators of calcification: fetuin-A, pyrophosphate and fibroblast growth factor-23 (FGF23). We randomized 41 postmenopausal women to 1 g/day of calcium as carbonate, or to a placebo containing no calcium. Measurements were performed at baseline and then 4 and 8 h after their first dose, and after 3 months of supplementation. Fetuin-A, pyrophosphate and FGF23 were measured in the first 10 participants allocated to calcium carbonate and placebo who completed the study. RESULTS T50 declined in both groups, the changes tending to be greater in the calcium group. Pyrophosphate declined from baseline in the placebo group at 4 h and was different from the calcium group at this time point (p = 0.04). There were no other significant between-groups differences. The changes in serum total calcium from baseline were significantly related to changes in T50 at 4 h (r = -0.32, p = 0.05) and 8 h (r = -0.39, p = 0.01), to fetuin-A at 3 months (r = 0.57, p = 0.01) and to pyrophosphate at 4 h (r = 0.61, p = 0.02). CONCLUSIONS These correlative findings suggest that serum calcium concentrations modulate the propensity of serum to calcify (T50), and possibly produce counter-regulatory changes in pyrophosphate and fetuin-A. This provides a possible mechanism by which calcium supplements might influence vascular calcification.
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van Genderen E, Clabbers MTB, Das PP, Stewart A, Nederlof I, Barentsen KC, Portillo Q, Pannu NS, Nicolopoulos S, Gruene T, Abrahams JP. Ab initio structure determination of nanocrystals of organic pharmaceutical compounds by electron diffraction at room temperature using a Timepix quantum area direct electron detector. Acta Crystallogr A Found Adv 2016; 72:236-42. [PMID: 26919375 PMCID: PMC4770873 DOI: 10.1107/s2053273315022500] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 11/25/2015] [Indexed: 11/10/2022] Open
Abstract
Until recently, structure determination by transmission electron microscopy of beam-sensitive three-dimensional nanocrystals required electron diffraction tomography data collection at liquid-nitrogen temperature, in order to reduce radiation damage. Here it is shown that the novel Timepix detector combines a high dynamic range with a very high signal-to-noise ratio and single-electron sensitivity, enabling ab initio phasing of beam-sensitive organic compounds. Low-dose electron diffraction data (∼ 0.013 e(-) Å(-2) s(-1)) were collected at room temperature with the rotation method. It was ascertained that the data were of sufficient quality for structure solution using direct methods using software developed for X-ray crystallography (XDS, SHELX) and for electron crystallography (ADT3D/PETS, SIR2014).
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Payne A, Wang X, Ivy M, Stewart A, Nelson K, Darris C, Nahashon S. Lysine mediation of neuroendocrine food regulation in guinea fowl. Poult Sci 2016; 95:276-86. [DOI: 10.3382/ps/pev326] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 09/15/2015] [Indexed: 01/12/2023] Open
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Cripps-Guazzone N, Jones E, Condron L, McLean K, Stewart A, Ridgway H. Rhizosphere and endophytic colonisation of ryegrass and sweet corn roots by the isolate Trichoderma atroviride LU132 at different soil pHs. ACTA ACUST UNITED AC 2016. [DOI: 10.30843/nzpp.2016.69.5918] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The colonisation of plant roots by biological control agents is dependent on abiotic factors one of the most important being soil pH The rhizosphere and endophytic colonisation of ryegrass and sweet corn roots by the biological control agent Trichoderma atroviride LU132 were assessed in a pot experiment with nonsterile soil at three different pHs (55 65 and 75) T atroviride LU132 colonised the roots of both plants regardless of the soil pH with 113147 x 106 CFU/g of dry rhizosphere soil (DRS) for ryegrass and 136350x105 CFU/g DRS for sweet corn T atroviride LU132 was able to colonise both plants endophytically regardless of soil pH However the isolate was recovered from entire ryegrass roots but only from the upper parts of sweet corn roots These experiments demonstrated that T atroviride LU132 colonised the rhizosphere and roots within a soil pH range common to most NZ soils which is a desirable trait for biological control agents
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Jones LE, Stewart A, Peters KL, McNaul M, Speers SJ, Fletcher NC, Bell SEJ. Infrared and Raman screening of seized novel psychoactive substances: a large scale study of >200 samples. Analyst 2016; 141:902-9. [DOI: 10.1039/c5an02326b] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The potential of IR absorption and Raman spectroscopy for rapid identification of novel psychoactive substances (NPS) has been tested using a set of 221 unsorted seized samples suspected of containing NPS.
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Kanu N, Grönroos E, Martinez P, Burrell RA, Yi Goh X, Bartkova J, Maya-Mendoza A, Mistrík M, Rowan AJ, Patel H, Rabinowitz A, East P, Wilson G, Santos CR, McGranahan N, Gulati S, Gerlinger M, Birkbak NJ, Joshi T, Alexandrov LB, Stratton MR, Powles T, Matthews N, Bates PA, Stewart A, Szallasi Z, Larkin J, Bartek J, Swanton C. SETD2 loss-of-function promotes renal cancer branched evolution through replication stress and impaired DNA repair. Oncogene 2015; 34:5699-708. [PMID: 25728682 PMCID: PMC4660036 DOI: 10.1038/onc.2015.24] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Revised: 12/29/2014] [Accepted: 01/06/2015] [Indexed: 12/13/2022]
Abstract
Defining mechanisms that generate intratumour heterogeneity and branched evolution may inspire novel therapeutic approaches to limit tumour diversity and adaptation. SETD2 (Su(var), Enhancer of zeste, Trithorax-domain containing 2) trimethylates histone-3 lysine-36 (H3K36me3) at sites of active transcription and is mutated in diverse tumour types, including clear cell renal carcinomas (ccRCCs). Distinct SETD2 mutations have been identified in spatially separated regions in ccRCC, indicative of intratumour heterogeneity. In this study, we have addressed the consequences of SETD2 loss-of-function through an integrated bioinformatics and functional genomics approach. We find that bi-allelic SETD2 aberrations are not associated with microsatellite instability in ccRCC. SETD2 depletion in ccRCC cells revealed aberrant and reduced nucleosome compaction and chromatin association of the key replication proteins minichromosome maintenance complex component (MCM7) and DNA polymerase δ hindering replication fork progression, and failure to load lens epithelium-derived growth factor and the Rad51 homologous recombination repair factor at DNA breaks. Consistent with these data, we observe chromosomal breakpoint locations are biased away from H3K36me3 sites in SETD2 wild-type ccRCCs relative to tumours with bi-allelic SETD2 aberrations and that H3K36me3-negative ccRCCs display elevated DNA damage in vivo. These data suggest a role for SETD2 in maintaining genome integrity through nucleosome stabilization, suppression of replication stress and the coordination of DNA repair.
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Stewart A, Parashar B, Patel M, O'Farrell D, Biagioli M, Devlin P, Mutyala S. American Brachytherapy Society consensus guidelines for thoracic brachytherapy for lung cancer. Brachytherapy 2015; 15:1-11. [PMID: 26561277 DOI: 10.1016/j.brachy.2015.09.006] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 08/28/2015] [Accepted: 09/02/2015] [Indexed: 10/22/2022]
Abstract
PURPOSE To update brachytherapy recommendations for pretreatment evaluation, treatment, and dosimetric issues for thoracic brachytherapy for lung cancer. METHODS AND MATERIALS Members of the American Brachytherapy Society with expertise in thoracic brachytherapy updated recommendations for thoracic brachytherapy based on literature review and clinical experience. RESULTS The American Brachytherapy Society consensus guidelines recommend the use of endobronchial brachytherapy for disease palliation in patients with central obstructing lesions, particularly in patients who have previously received external beam radiotherapy. The use of interstitial implants after incomplete resection may improve outcomes and provide enhanced palliation. Early reports support the use of CT-guided intratumoral volume implants within clinical studies. The use of brachytherapy routinely after sublobar resection is not generally recommended, unless within the confines of a clinical trial or a registry. CONCLUSIONS American Brachytherapy Society recommendations for thoracic brachytherapy are provided. Practitioners are encouraged to follow these guidelines and to develop further clinical trials to examine this treatment modality to increase the evidence base for its use.
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Schepelmann M, Yarova PL, Lopez-Fernandez I, Davies TS, Brennan SC, Edwards PJ, Aggarwal A, Graça J, Rietdorf K, Matchkov V, Fenton RA, Chang W, Krssak M, Stewart A, Broadley KJ, Ward DT, Price SA, Edwards DH, Kemp PJ, Riccardi D. The vascular Ca2+-sensing receptor regulates blood vessel tone and blood pressure. Am J Physiol Cell Physiol 2015; 310:C193-204. [PMID: 26538090 DOI: 10.1152/ajpcell.00248.2015] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 10/29/2015] [Indexed: 12/28/2022]
Abstract
The extracellular calcium-sensing receptor CaSR is expressed in blood vessels where its role is not completely understood. In this study, we tested the hypothesis that the CaSR expressed in vascular smooth muscle cells (VSMC) is directly involved in regulation of blood pressure and blood vessel tone. Mice with targeted CaSR gene ablation from vascular smooth muscle cells (VSMC) were generated by breeding exon 7 LoxP-CaSR mice with animals in which Cre recombinase is driven by a SM22α promoter (SM22α-Cre). Wire myography performed on Cre-negative [wild-type (WT)] and Cre-positive (SM22α)CaSR(Δflox/Δflox) [knockout (KO)] mice showed an endothelium-independent reduction in aorta and mesenteric artery contractility of KO compared with WT mice in response to KCl and to phenylephrine. Increasing extracellular calcium ion (Ca(2+)) concentrations (1-5 mM) evoked contraction in WT but only relaxation in KO aortas. Accordingly, diastolic and mean arterial blood pressures of KO animals were significantly reduced compared with WT, as measured by both tail cuff and radiotelemetry. This hypotension was mostly pronounced during the animals' active phase and was not rescued by either nitric oxide-synthase inhibition with nitro-l-arginine methyl ester or by a high-salt-supplemented diet. KO animals also exhibited cardiac remodeling, bradycardia, and reduced spontaneous activity in isolated hearts and cardiomyocyte-like cells. Our findings demonstrate a role for CaSR in the cardiovascular system and suggest that physiologically relevant changes in extracellular Ca(2+) concentrations could contribute to setting blood vessel tone levels and heart rate by directly acting on the cardiovascular CaSR.
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Stewart A, Ganguli A, FitzGerald R, Pirmohamed M. Variation in warfarin prescribing and dosing in the UK: a national survey of anticoagulation clinics. J Clin Pharm Ther 2015; 40:466-71. [PMID: 26032753 DOI: 10.1111/jcpt.12291] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2015] [Accepted: 05/05/2015] [Indexed: 01/10/2023]
Abstract
WHAT IS KNOWN AND OBJECTIVE Clinical practice in the initiation, prescribing, dosing and monitoring of warfarin in the UK varies, but this has not been adequately documented. The objective was to undertake a survey on current clinical practice in this area, and how it compares with national guidelines that have been developed by the British Committee for Standards in Haematology. METHODS A national online survey of anticoagulation clinics was performed using Survey Monkey(®) . The survey was designed to capture data for prescribing, dosing and monitoring of anticoagulation with warfarin. RESULTS Of 85 clinics who responded to the survey, most were run by secondary care (68%), facilitated by specialist nurses (58%) and followed standard guidelines for the management of warfarin (87%). The majority of clinics indicated their target international normalized ratio (INR) for patients with atrial fibrillation (AF) (69/73; 94·5%) was between 2·0 and 3·0, but the indicated target INR for mechanical heart valves was more variable. Initiation and loading dosing regimens were a major source of variability with uncertainty surrounding individual patient factors such as age, ethnicity and BMI. WHAT IS NEW AND CONCLUSIONS Current practice amongst UK anticoagulation clinics largely follows current national guidelines but better guidance on dosing, taking into account factors that determine interindividual variability in daily warfarin dose requirements would improve and standardize oral anticoagulation with warfarin.
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Tumusiime D, Stewart A, Venter F. Effect of physiotherapeutic exercises on peripheral neuropathy, functional limitations of lower extremity and quality of life in people with HIV. Physiotherapy 2015. [DOI: 10.1016/j.physio.2015.03.1542] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Maleka M, Stewart A, Hale L, Becker P. The construct validation of the Maleka Stroke Community Reintegration Measure (M-SCRIM). Physiotherapy 2015. [DOI: 10.1016/j.physio.2015.03.1791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Godlwana L, Stewart A, Musenge E. Mobility during the intermediate stage of rehabilitation after lower limb amputation from an under resourced community: a randomized controlled trial. Physiotherapy 2015. [DOI: 10.1016/j.physio.2015.03.3243] [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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