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1.
Heart ; 2024 May 16.
Article in English | MEDLINE | ID: mdl-38754969

ABSTRACT

BACKGROUND: The practical application of 'virtual' (computed) fractional flow reserve (vFFR) based on invasive coronary angiogram (ICA) images is unknown. The objective of this cohort study was to investigate the potential of vFFR to guide the management of unselected patients undergoing ICA. The hypothesis was that it changes management in >10% of cases. METHODS: vFFR was computed using the Sheffield VIRTUheart system, at five hospitals in the North of England, on 'all-comers' undergoing ICA for non-ST-elevation myocardial infarction acute coronary syndrome (ACS) and chronic coronary syndrome (CCS). The cardiologists' management plan (optimal medical therapy, percutaneous coronary intervention (PCI), coronary artery bypass surgery or 'more information required') and confidence level were recorded after ICA, and again after vFFR disclosure. RESULTS: 517 patients were screened; 320 were recruited: 208 with ACS and 112 with CCS. The median vFFR was 0.82 (0.70-0.91). vFFR disclosure did not change the mean number of significantly stenosed vessels per patient (1.16 (±0.96) visually and 1.18 (±0.92) with vFFR (p=0.79)). A change in intended management following vFFR disclosure occurred in 22% of all patients; in the ACS cohort, there was a 62% increase in the number planned for medical management, and in the CCS cohort, there was a 31% increase in the number planned for PCI. In all patients, vFFR disclosure increased physician confidence from 8 of 10 (7.33-9) to 9 of 10 (8-10) (p<0.001). CONCLUSION: The addition of vFFR to ICA changed intended management strategy in 22% of patients, provided a detailed and specific 'all-in-one' anatomical and physiological assessment of coronary artery disease, and was accompanied by augmentation of the operator's confidence in the treatment strategy.

2.
Age Ageing ; 53(Supplement_2): ii80-ii89, 2024 May 11.
Article in English | MEDLINE | ID: mdl-38748910

ABSTRACT

BACKGROUND: Increasing fruit and vegetable (FV) consumption is associated with reduced cardiovascular disease risk in observational studies but with little evidence from randomised controlled trials (RCTs). The impact of concurrent pharmacological therapy is unknown. OBJECTIVE: To pool data from six RCTs to examine the effect of increasing FV intake on blood pressure (BP) and lipid profile, also exploring whether effects differed by medication use. DESIGN: Across trials, dietary intake was assessed by diet diaries or histories, lipids by routine biochemical methods and BP by automated monitors. Linear regression provided an estimate of the change in lipid profile or BP associated with a one portion increase in self-reported daily FV intake, with interaction terms fitted for medication use. RESULTS: The pooled sample included a total of 554 participants (308 males and 246 females). Meta-analysis of regression coefficients revealed no significant change in either systolic or diastolic BP per portion FV increase, although there was significant heterogeneity across trials for systolic BP (I2 = 73%). Neither adjusting for change in body mass index, nor analysis according to use of anti-hypertensive medication altered the relationship. There was no significant change in lipid profile per portion FV increase, although there was a significant reduction in total cholesterol among those not on lipid-lowering therapy (P < 0.05 after Bonferroni correction). CONCLUSION: Pooled analysis of six individual FV trials showed no impact of increasing intake on BP or lipids, but there was a total cholesterol-lowering effect in those not on lipid-lowering therapy.


Subject(s)
Blood Pressure , Fruit , Lipids , Randomized Controlled Trials as Topic , Vegetables , Humans , Blood Pressure/drug effects , Male , Female , Middle Aged , Lipids/blood , Aged , Diet, Healthy , Antihypertensive Agents/therapeutic use , Biomarkers/blood
3.
Article in English | MEDLINE | ID: mdl-38696538

ABSTRACT

CONTEXT: Head and neck paragangliomas (HNPGLs) are rare, usually benign, slow-growing tumours arising from neural crest-derived tissue. Definitive management pathways for HNPGLs have yet to be clearly defined. OBJECTIVE: To review our experience of the clinical features and management of these tumours and to analyse outcomes of different treatment modalities. METHODS: Demographic and clinical data were obtained from The Northern Ireland Electronic Care Record (NIECR) as well from a prospectively maintained HNPGL database between January 2011 through December 2023. RESULTS: There were 87 patients; 50 females: 37 males with a mean age of 52.3 ± 14.2 years old (range 17-91 years old). 58.6% (n = 51) of patients had carotid body tumours, 25.2% (n = 22) glomus vagal tumours, 6.8% (n = 6) tumours in the middle ear, 2.2% (n = 2) in the parapharyngeal space and 1.1% (n = 1) in the sphenoid sinus. 5.7% (n = 5) of patients had multifocal disease. The mean tumour size at presentation was 3.2 ± 1.4 cm (range 0.5-6.9 cm). Pathogenic SDHD mutations were identified in 41.3% (n = 36), SDHB in 12.6% (n = 11), SDHC in 2.2% (n = 2) and SDHA in 1.1% (n = 1) of the patients. Overall treatment modalities included surgery alone in 51.7% (n = 45) of patients, radiotherapy in 14.9% (n = 13), observation in 28.7% (n = 25), and somatostatin analogue therapy with octreotide in 4.5% (n = 4) of patients. Factors associated with a significantly higher risk of recurrence included age over 60 years (p = .04), tumour size exceeding 2 cm (p = .03), positive SDHx variants (p = .01), and vagal and jugular tumours (p = .04). CONCLUSION: The majority of our patients underwent initial surgical intervention and achieved disease stability. Our results suggest that carefully selected asymptomatic or medically unfit patients can be safely observed provided lifelong surveillance is maintained. We advocate for the establishment of a UK and Ireland national HNPGL registry, to delineate optimal management strategies for these rare tumours and improve long term outcomes.

4.
EClinicalMedicine ; 61: 102052, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37425372

ABSTRACT

Background: Endocardial catheter ablation (CA) has limited long-term benefit for persistent and longstanding persistent atrial fibrillation (PersAF/LSPAF). We hypothesized hybrid epicardial-endocardial ablation (HA) would have superior effectiveness compared to CA, including repeat (rCA), in PersAF/LSPAF. Methods: CEASE-AF (NCT02695277) is a prospective, multi-center, randomized controlled trial. Nine hospitals in Poland, Czech Republic, Germany, United Kingdom, and the Netherlands enrolled eligible participants with symptomatic, drug refractory PersAF and left atrial diameter (LAD) > 4.0 cm or LSPAF. Randomization was 2:1 to HA or CA by an independent statistician and stratified by site. Treatment assignments were masked to the core rhythm monitoring laboratory. For HA, pulmonary veins (PV) and left posterior atrial wall were isolated with thoracoscopic epicardial ablation including left atrial appendage exclusion. Endocardial touch-up ablation was performed 91-180 days post-index procedure. For CA, endocardial PV isolation and optional substrate ablation were performed. rCA was permitted between days 91-180. Primary effectiveness was freedom from AF/atrial flutter/atrial tachycardia >30-s through 12-months absent class I/III anti-arrhythmic drugs except those not exceeding previously failed doses. It was assessed in the modified intention-to-treat (mITT) population who had the index procedure and follow-up data. Major complications were assessed in the ITT population who had the index procedure. Thirty-six month follow-up continues. Findings: Enrollment began November 20, 2015 and ended May 22, 2020. In 154 ITT patients (102 HA; 52 CA), 75% were male, mean age was 60.7 ± 7.9 years, mean LAD was 4.7 ± 0.4 cm, and 81% had PersAF. Primary effectiveness was 71.6% (68/95) in HA versus 39.2% (20/51) in CA (absolute benefit increase: 32.4% [95% CI 14.3%-48.0%], p < 0.001). Major complications through 30-days after index procedures plus 30-days after second stage/rCA were similar (HA: 7.8% [8/102] versus CA: 5.8% [3/52], p = 0.75). Interpretation: HA had superior effectiveness compared to CA/rCA in PersAF/LSPAF without significant procedural risk increase. Funding: AtriCure, Inc.

6.
J Nutr Sci ; 12: e13, 2023.
Article in English | MEDLINE | ID: mdl-36843970

ABSTRACT

Peer support interventions for dietary change may offer cost-effective alternatives to interventions led by health professionals. This process evaluation of a trial to encourage the adoption and maintenance of a Mediterranean diet in a Northern European population at high CVD risk (TEAM-MED) aimed to investigate the feasibility of implementing a group-based peer support intervention for dietary change, positive elements of the intervention and aspects that could be improved. Data on training and support for the peer supporters; intervention fidelity and acceptability; acceptability of data collection processes for the trial and reasons for withdrawal from the trial were considered. Data were collected from observations, questionnaires and interviews, with both peer supporters and trial participants. Peer supporters were recruited and trained to result in successful implementation of the intervention; all intended sessions were run, with the majority of elements included. Peer supporters were complimentary of the training, and positive comments from participants centred around the peer supporters, the intervention materials and the supportive nature of the group sessions. Attendance at the group sessions, however, waned over the intervention, with suggested effects on intervention engagement, enthusiasm and group cohesion. Reduced attendance was reportedly a result of meeting (in)frequency and organisational concerns, but increased social activities and group-based activities may also increase engagement, group cohesion and attendance. The peer support intervention was successfully implemented and tested, but improvements can be suggested and may enhance the successful nature of these types of interventions. Some consideration of personal preferences may also improve outcomes.


Subject(s)
Diet, Mediterranean , Peer Group , Social Support , Humans , Health Promotion , Surveys and Questionnaires
7.
BMJ Case Rep ; 15(12)2022 Dec 21.
Article in English | MEDLINE | ID: mdl-36543370

ABSTRACT

A man in his 20s attended the emergency department with three days of fever, headache, reduced appetite and a sore throat. COVID-19 point-of-care test was negative. Blood cultures grew a gram-negative coccobacillus, Neisseria elongata Following an episode of confusion, MRI head revealed septic emboli. Prolapse of the mitral valve with regurgitation was noted on echocardiography. Infection was found to have originated from multiple dental caries and treatment required a combination of dental extraction, prolonged antibiotic therapy and surgery for mitral valve repair.N. elongata is part of the normal oropharyngeal flora but is also a rare cause of endocarditis. There are no established treatment guidelines for endocarditis of this aetiology. N. elongata endocarditis may present atypically, with a murmur only developing several days later. 'Classical' stigmata should not be relied on to make a diagnosis. N. elongata predominantly affects the left side of the heart and predisposes to embolic events.


Subject(s)
COVID-19 , Dental Caries , Endocarditis, Bacterial , Endocarditis , Male , Humans , Endocarditis, Bacterial/complications , Endocarditis, Bacterial/diagnosis , Endocarditis, Bacterial/surgery , Mitral Valve/surgery
8.
Endocr Relat Cancer ; 29(10): R157-R172, 2022 10 01.
Article in English | MEDLINE | ID: mdl-35938916

ABSTRACT

Pituitary neuroendocrine tumours (PitNETs) associated with paragangliomas or phaeochromocytomas are rare. SDHx variants are estimated to be associated with 0.3-1.8% of PitNETs. Only a few case reports have documented the association with MAX variants. Prolactinomas are the most common PitNETs occurring in patients with SDHx variants, followed by somatotrophinomas, clinically non-functioning tumours and corticotrophinomas. One pituitary carcinoma has been described. SDHC, SDHB and SDHA mutations are inherited in an autosomal dominant fashion and tumorigenesis seems to adhere to Knudson's two-hit hypothesis. SDHD and SDHAF2 mutations most commonly have paternal inheritance. Immunohistochemistry for SDHB or MAX and loss of heterozygosity analysis can support the assessment of pathogenicity of the variants. Metabolomics is promising in the diagnosis of SDHx-related disease. Future research should aim to further clarify the role of SDHx and MAX variants or other genes in the molecular pathogenesis of PitNETs, including pseudohypoxic and kinase signalling pathways along with elucidating epigenetic mechanisms to predict tumour behaviour.


Subject(s)
Adrenal Gland Neoplasms , Basic-Leucine Zipper Transcription Factors/genetics , Neuroendocrine Tumors , Paraganglioma , Pituitary Neoplasms , Adrenal Gland Neoplasms/genetics , Factor X/genetics , Factor X/metabolism , Germ-Line Mutation , Humans , Mutation , Neuroendocrine Tumors/genetics , Paraganglioma/pathology , Pituitary Neoplasms/genetics , Pituitary Neoplasms/pathology , Succinate Dehydrogenase/genetics
9.
Lancet Diabetes Endocrinol ; 10(10): 700-709, 2022 10.
Article in English | MEDLINE | ID: mdl-36007536

ABSTRACT

BACKGROUND: Central diabetes insipidus is a rare neuroendocrine condition. Data on treatment-associated side-effects, psychological comorbidities, and incorrect management are scarce. The aim of this study was to investigate patients' perspectives on their disease. METHODS: This study used a cross-sectional, web-based, anonymous survey, developed by endocrinologists and patient representatives, to collect the opinions of patients with central diabetes insipidus on management and complications of their disease, psychological comorbidities, degree of knowledge and awareness of the condition among health-care professionals, and renaming the disease to avoid confusion with diabetes mellitus (diabetes). FINDINGS: Between Aug 23, 2021, and Feb 7, 2022, 1034 patients with central diabetes insipidus participated in the survey. 91 (9%) participants were children and adolescents (37 [41%] girls and 54 [59%] boys; median age 10 years [IQR 6-15]) and 943 (91%) were adults (757 [80%] women and 186 [20%] men]; median age 44 years [34-54]). 488 (47%) participants had isolated posterior pituitary dysfunction and 546 (53%) had combined anterior and posterior pituitary dysfunction. Main aetiologies were idiopathic (315 [30%] of 1034 participants) and tumours and cysts (pre-surgical 217 [21%]; post-surgical 254 [25%]). 260 (26%; 95% CI [0·23-0·29]) of 994 patients on desmopressin therapy had hyponatraemia leading to hospitalisation. Patients who routinely omitted or delayed desmopressin to allow intermittent aquaresis had a significantly lower prevalence of hyponatraemia compared with those not aware of this approach (odds ratio 0·55 [95% CI 0·39-0·77]; p=0·0006). Of patients who had to be hospitalised for any medical reason, 71 (13%; 95% CI 0·10-0·16) of 535 patients did not receive desmopressin while in a fasting state (nil by mouth) without intravenous fluid replacement and reported symptoms of dehydration. 660 (64%; 0·61-0·67) participants reported lower quality of life, and 369 (36%; 0·33-0·39) had psychological changes subjectively associated with their central diabetes insipidus. 823 (80%; 0·77-0·82) participants encountered a situation where central diabetes insipidus was confused with diabetes mellitus (diabetes) by health-care professionals. 884 (85%; 0·83-0·88) participants supported renaming the disease; the most favoured alternative names were vasopressin deficiency and arginine vasopressin deficiency. INTERPRETATION: This is the largest survey of patients with central diabetes insipidus, reporting a high prevalence of treatment-associated side-effects, mismanagement during hospitalisation, psychological comorbidities, and a clear support for renaming the disease. Our data are the first to indicate the value of routinely omitting or delaying desmopressin. FUNDING: Swiss National Science Foundation, Swiss Academy of Medical Sciences, and G&J Bangerter-Rhyner-Foundation.


Subject(s)
Diabetes Insipidus, Neurogenic , Diabetes Insipidus , Diabetes Mellitus , Hyponatremia , Adolescent , Adult , Arginine , Child , Cross-Sectional Studies , Deamino Arginine Vasopressin/therapeutic use , Diabetes Insipidus/diagnosis , Diabetes Insipidus/etiology , Diabetes Insipidus, Neurogenic/complications , Diabetes Insipidus, Neurogenic/etiology , Female , Humans , Hyponatremia/complications , Hyponatremia/etiology , Internet , Male , Middle Aged , Morbidity , Quality of Life
10.
Br J Nutr ; 128(7): 1322-1334, 2022 10 14.
Article in English | MEDLINE | ID: mdl-34605384

ABSTRACT

Adhering to a Mediterranean diet (MD) is associated with reduced CVD risk. This study aimed to explore methods of increasing MD adoption in a non-Mediterranean population at high risk of CVD, including assessing the feasibility of a developed peer support intervention. The Trial to Encourage Adoption and Maintenance of a MEditerranean Diet was a 12-month pilot parallel group RCT involving individuals aged ≥ 40 year, with low MD adherence, who were overweight, and had an estimated CVD risk ≥ 20 % over ten years. It explored three interventions, a peer support group, a dietician-led support group and a minimal support group to encourage dietary behaviour change and monitored variability in Mediterranean Diet Score (MDS) over time and between the intervention groups, alongside measurement of markers of nutritional status and cardiovascular risk. 118 individuals were assessed for eligibility, and 75 (64 %) were eligible. After 12 months, there was a retention rate of 69 % (peer support group 59 %; DSG 88 %; MSG 63 %). For all participants, increases in MDS were observed over 12 months (P < 0·001), both in original MDS data and when imputed data were used. Improvements in BMI, HbA1c levels, systolic and diastolic blood pressure in the population as a whole. This pilot study has demonstrated that a non-Mediterranean adult population at high CVD risk can make dietary behaviour change over a 12-month period towards an MD. The study also highlights the feasibility of a peer support intervention to encourage MD behaviour change amongst this population group and will inform a definitive trial.


Subject(s)
Cardiovascular Diseases , Diet, Mediterranean , Humans , Adult , Pilot Projects , Counseling , European People
11.
J Card Surg ; 36(12): 4759-4761, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34499379

ABSTRACT

Glomus tumors are rare benign soft tissue lesions, most commonly found on the skin. They are an extremely rare cause of the cardiac tumor. We report a case of right atrial glomus tumor excised using a novel technique utilizing cardiac electroanatomical mapping techniques ordinarily used for arrhythmia surgery.


Subject(s)
Glomus Tumor , Heart Neoplasms , Arrhythmias, Cardiac , Endocardium/surgery , Heart Atria/diagnostic imaging , Heart Atria/surgery , Heart Neoplasms/diagnostic imaging , Heart Neoplasms/surgery , Humans
12.
BMJ Case Rep ; 14(7)2021 Jul 12.
Article in English | MEDLINE | ID: mdl-34253523

ABSTRACT

A 47-year-old man was commenced on levothyroxine following a diagnosis of subclinical hypothyroidism with nonspecific symptoms. Despite increasing doses of levothyroxine, his thyroid-stimulating hormone (TSH) remained elevated and he was referred for further assessment as he was unable to tolerate further titration. On assessment, his thyroid function demonstrated an elevated TSH and elevated free-T4. The initial impression was of iatrogenic thyrotoxicosis, with possible underlying thyroid hormone resistance, TSHoma or assay interference. After discontinuation of levothyroxine, free-T4 normalised but TSH remained elevated. There was a normal response to thyrotropin-releasing hormone (TRH) testing. T3 suppression testing demonstrated free-T4 reduction but persistently high TSH. THRß sequencing was normal. TSH measurement by alternative assays revealed discrepant results. Gel filtration chromatography revealed the presence of high-molecular weight TSH variant alongside normal TSH. Macro-TSH is a rare phenomenon with spuriously elevated TSH and which may mimic subclinical hypothyroidism. Recognition of macro-TSH avoids misdiagnosis and prevents inappropriate treatment.


Subject(s)
Hypothyroidism , Thyrotropin , Humans , Hypothyroidism/diagnosis , Hypothyroidism/drug therapy , Male , Middle Aged , Thyroid Function Tests , Thyrotropin-Releasing Hormone , Thyroxine , Triiodothyronine
13.
Quant Imaging Med Surg ; 11(4): 1470-1482, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33816183

ABSTRACT

BACKGROUND: Left ventricular (LV) kinetic energy (KE) assessment by four-dimensional flow cardiovascular magnetic resonance (4D flow CMR) may offer incremental value over routine assessment in aortic stenosis (AS). The main objective of this study is to investigate the LV KE in patients with AS before and after the valve intervention. In addition, this study aimed to investigate if LV KE offers incremental value for its association to the six-minute walk test (6MWT) or LV remodelling post-intervention. METHODS: We recruited 18 patients with severe AS. All patients underwent transthoracic echocardiography for mean pressure gradient (mPG), CMR including 4D flow and 6MWT. Patients were invited for post-valve intervention follow-up CMR at 3 months and twelve patients returned for follow-up CMR. KE assessment of LV blood flow and the components (direct, delayed, retained and residual) were carried out for all cases. LV KE parameters were normalised to LV end-diastolic volume (LVEDV). RESULTS: For LV blood flow KE assessment, the metrics including time delay (TD) for peak E-wave from base to mid-ventricle (14±48 vs. 2.5±9.75 ms, P=0.04), direct (4.91±5.07 vs. 1.86±1.72 µJ, P=0.01) and delayed (2.46±3.13 vs. 1.38±1.15 µJ, P=0.03) components of LV blood flow demonstrated a significant change between pre- and post-valve intervention. Only LV KEiEDV (r=-0.53, P<0.01), diastolic KEiEDV (r=-0.53, P<0.01) and Ewave KEiEDV (r=-0.38, P=0.04) demonstrated association to the 6MWT. However, Pre-operative LV KEiEDV (r=0.67, P=0.02) demonstrated association to LV remodelling post valve intervention. CONCLUSIONS: LV blood flow KE is associated with 6MWT and LV remodelling in patients with AS. LV KE assessment provides incremental value over routine LV function and pressure gradient (PG) assessment in AS.

14.
Open Heart ; 7(2)2020 10.
Article in English | MEDLINE | ID: mdl-33020254

ABSTRACT

Disseminating the practice of minimally invasive mitral surgery (mini-MVS) can be challenging, despite its original case reports a few decades ago. The penetration of this technology into clinical practice has been limited to centres of excellence, and mitral surgery in most general cardiothoracic centres remains to be conducted via sternotomy access as a first line. The process for the uptake of mini-MVS requires clearer guidance and standardisation for the processes involved in its implementation. In this statement, a consensus agreement is outlined that describes the benefits of mini-MVS, including reduced postoperative bleeding, reduced wound infection, enhanced recovery and patient satisfaction. Technical considerations require specific attention and can be introduced through simulation and/or use in conventional cases. Either endoballoon or aortic cross clamping is recommended, as well as femoral or central aortic cannulation, with the use of appropriate adjuncts and instruments. A coordinated team-based approach that encourages ownership of the programme by the team members is critical. A designated proctor is also recommended. The organisation of structured training and simulation, as well as planning the initial cases, is an important step to consider. The importance of pre-empting complications and dealing with adverse events is described, including re-exploration, conversion to sternotomy, unilateral pulmonary oedema and phrenic nerve injury. Accounting for both institutional and team considerations can effectively facilitate the introduction of a mini-MVS service. This involves simulation, team-based training, visits to specialist centres and involvement of a designated proctor to oversee the initial cases.


Subject(s)
Cardiac Surgical Procedures/standards , Cardiology/standards , Heart Valve Diseases/surgery , Minimally Invasive Surgical Procedures/standards , Mitral Valve/surgery , State Medicine/standards , Cardiac Surgical Procedures/adverse effects , Consensus , Heart Valve Diseases/diagnostic imaging , Heart Valve Diseases/physiopathology , Humans , Minimally Invasive Surgical Procedures/adverse effects , Mitral Valve/diagnostic imaging , Mitral Valve/physiopathology , Patient Care Team , Patient Satisfaction , Postoperative Complications/etiology , Program Development , Treatment Outcome , United Kingdom
15.
Oxf Med Case Reports ; 2020(7): omaa045, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32728448

ABSTRACT

A 29-year-old male, with chronic atopic dermatitis (AD), presented with a 2-week history of fatigue, pyrexia and weight loss. Examination showed eczematous patches with lichenified papules, erosions on the right shin and a new murmur. Blood cultures isolated methicillin-sensitive Staphylococcus aureus. Transthoracic echocardiography showed vegetation on the tricuspid valve (TV) that was adherent to the septal leaflet. He was treated for infective endocarditis, attributed to poorly controlled AD, with intravenous Flucloxacillin. Due to ongoing sepsis and pulmonary septic emboli, Clindamycin was added. He underwent TV repair; the septal leaflet was excised, and the remnant two leaflets were brought together with a ring. His patent foramen ovale was closed. His skin was treated with topical steroids and emollients. Right-sided endocarditis of an intact TV is uncommon in a non-intravenous drug user. Therefore, this novel case portrays the importance of aggressively managing AD as it is a risk factor for significant systemic infections.

16.
Sci Rep ; 10(1): 1437, 2020 Jan 29.
Article in English | MEDLINE | ID: mdl-31996754

ABSTRACT

Understanding the nature of gas transport from an underground nuclear explosion (UNE) is required for evaluating the ability to detect and interpret either on-site or atmospheric signatures of noble gas radionuclides resulting from the event. We performed a pressure and chemical tracer monitoring experiment at the site of an underground nuclear test that occurred in a tunnel in Nevada to evaluate the possible modes of gas transport to the surface. The site represents a very well-contained, low gas-permeability end member for past UNEs at the Nevada National Security Site. However, there is very strong evidence that gases detected at the surface during a period of low atmospheric pressure resulted from fractures of extremely small aperture that are essentially invisible. Our analyses also suggest that gases would have easily migrated to the top of the high-permeability collapse zone following the detonation minimizing the final distance required for migration along these narrow fractures to the surface. This indicates that on-site detection of gases emanating from such low-permeability sites is feasible while standoff detection of atmospheric plumes may also be possible at local distances for sufficiently high fracture densities. Finally, our results show that gas leakage into the atmosphere also occurred directly from the tunnel portal and should be monitored in future tunnel gas sampling experiments for the purpose of better understanding relative contributions to detection of radioxenon releases via both fracture network and tunnel transport.

17.
Am J Clin Nutr ; 110(5): 1138-1147, 2019 11 01.
Article in English | MEDLINE | ID: mdl-31559433

ABSTRACT

BACKGROUND: Observational studies have suggested an inverse association between low serum 25-hydroxyvitamin D [25(OH)D] concentrations and development of type 2 diabetes. High-quality trials are required to test the hypothesis that vitamin D is a direct contributor to type 2 diabetes pathogenesis. OBJECTIVE: The purpose of this double-blind randomized placebo-controlled trial was to investigate the effect of vitamin D3 supplementation on insulin resistance (IR) and ß-cell function in people with prediabetes and suboptimal vitamin D status (<50 nmol/L). METHODS: Sixty-six individuals were randomly assigned to receive 3000 IU (75 µg) vitamin D3 or placebo daily for 26 wk. Compliance was monitored by pill count and change in serum 25(OH)D concentration using LC-MS. The primary endpoint was between-group difference in change in IR assessed using a 2-step euglycemic-hyperinsulinemic clamp combined with infusion of tritiated glucose. An oral-glucose-tolerance test was performed pre- and postintervention to calculate indices of ß-cell function. Between-group comparisons were made using ANCOVA. RESULTS: In total, 64 participants completed the study. Baseline serum 25(OH)D concentrations in the vitamin D3 and placebo group were 30.7 and 30.0 nmol/L, with status increasing by 70.5 nmol/L and 5.3 nmol/L, respectively (between-group difference in vitamin D: 65.8 nmol/L; 95% CI: 54.2, 77.3 nmol/L; P < 0.01), after supplementation. There was no difference between groups in measures of whole-body, peripheral, or hepatic IR or in any measure of glycemic control or ß-cell function. CONCLUSION: This study employed a robust assessment of IR and ß-cell function and targeted a high-risk population with low 25(OH)D status at baseline and found that vitamin D3 supplementation had no effect on insulin action in people with prediabetes.This trial was registered on clinicaltrials.gov as NCT01889810.


Subject(s)
Cholecalciferol/administration & dosage , Dietary Supplements , Insulin Resistance , Insulin-Secreting Cells/physiology , Prediabetic State/physiopathology , Adult , Aged , Double-Blind Method , Female , Humans , Male , Middle Aged
18.
Article in English | MEDLINE | ID: mdl-31117051

ABSTRACT

Pregnancy in acromegaly is rare and generally safe, but tumour expansion may occur. Managing tumour expansion during pregnancy is complex, due to the potential complications of surgery and side effects of anti-tumoural medication. A 32-year-old woman was diagnosed with acromegaly at 11-week gestation. She had a large macroadenoma invading the suprasellar cistern. She developed bitemporal hemianopia at 20-week gestation. She declined surgery and was commenced on 100 µg subcutaneous octreotide tds, with normalisation of her visual fields after 2 weeks of therapy. She had a further deterioration in her visual fields at 24-week gestation, which responded to an increase in subcutaneous octreotide to 150 µg tds. Her vision remained stable for the remainder of the pregnancy. She was diagnosed with gestational diabetes at 14/40 and was commenced on basal bolus insulin regimen at 22/40 gestation. She otherwise had no obstetric complications. Foetal growth continued along the 50th centile throughout pregnancy. She underwent an elective caesarean section at 34/40, foetal weight was 3.2 kg at birth with an APGAR score of 9. The neonate was examined by an experienced neonatologist and there were no congenital abnormalities identified. She opted not to breastfeed and she is menstruating regularly post-partum. She was commenced on octreotide LAR 40 mg and referred for surgery. At last follow-up, 2 years post-partum, the infant has been developing normally. In conclusion, our case describes a first presentation of acromegaly in pregnancy and rescue of visual field loss with somatostatin analogue therapy. Learning points: Tumour expansion may occur in acromegaly during pregnancy. Treatment options for tumour expansion in pregnancy include both medical and surgical options. Somatostatin analogues may be a viable medical alternative to surgery in patients with tumour expansion during pregnancy.

19.
Eur J Endocrinol ; 180(4): K21-K29, 2019 Apr 01.
Article in English | MEDLINE | ID: mdl-30620709

ABSTRACT

Pregnancy is rarely reported in acromegaly. Many patients are diagnosed in later life and younger patients may have subfertility due to hypopituitarism. We present a case series of 17 pregnancies in 12 women with acromegaly. Twelve women with acromegaly who completed pregnancy were identified from centres involved in the Irish Pituitary Study. Eleven women had pituitary macroadenomas and one woman had a microadenoma. Only 5/17 pregnancies had optimal biochemical control of acromegaly preconception, as defined by IGF-1 concentration in the age-related reference level and plasma GH concentration of <2 µg/L. In 6/17 pregnancies, dopamine agonist treatment was continued during pregnancy; all other acromegaly treatments were discontinued during pregnancy. Effect of pregnancy on acromegaly: No patient developed new visual field abnormalities, or symptoms suggestive of tumour expansion during pregnancy. In 9/12 patients, plasma IGF-1 concentrations that were elevated preconception normalised during pregnancy. There was a reduction in plasma IGF-1 concentrations, though not into the normal range, in a further two pregnancies. Effect of acromegaly on pregnancy: 15 healthy babies were born at term; one patient underwent emergency C-section at 32 weeks for pre-eclampsia, and one twin pregnancy had an elective C-section at 35 weeks' gestation. Blood pressure remained within normal limits in the remainder of the pregnancies. Gestational diabetes did not develop in any pregnancy. Our data suggests that pregnancy in women with acromegaly is generally safe, from a maternal and foetal perspective. Furthermore, biochemical control tends to improve despite the withdrawal of somatostatin analogue therapy during pregnancy.


Subject(s)
Acromegaly/blood , Insulin-Like Growth Factor I/metabolism , Pregnancy Complications/blood , Acromegaly/diagnosis , Adult , Biomarkers/blood , Female , Humans , Infant, Newborn , Pregnancy , Pregnancy Complications/diagnosis
20.
Thorac Cardiovasc Surg ; 67(2): 117-119, 2019 03.
Article in English | MEDLINE | ID: mdl-28403480

ABSTRACT

We introduce a maneuver to perform the box lesion as a part of Cox maze IV procedure with single radiofrequency clamp. The maneuver entails engaging the right pulmonary veins with the clamp, then advancing the clamp jaws underneath the superior vena cava through the transverse sinus to include the roof and the left pulmonary veins in the clamp. We regularly use this technique for box lesion with desirable transmurality.


Subject(s)
Atrial Fibrillation/surgery , Heart Atria/surgery , Pulmonary Veins/surgery , Radiofrequency Ablation/instrumentation , Surgical Instruments , Atrial Fibrillation/diagnosis , Atrial Fibrillation/physiopathology , Constriction , Equipment Design , Heart Atria/physiopathology , Humans , Pulmonary Veins/physiopathology , Radiofrequency Ablation/methods
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