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3.
Plants (Basel) ; 9(1)2020 Jan 02.
Article in English | MEDLINE | ID: mdl-31906418

ABSTRACT

Portulaca grandiflora simultaneously utilizes both the C4 and Crassulacean acid metabolism (CAM) photosynthetic pathways. Our goal was to determine whether CAM developed and was functional simultaneously with the C4 pathway in cotyledons of P. grandiflora. We studied during development whether CAM would be induced with water stress by monitoring the enzyme activity, leaf structure, JO2 (rate of O2 evolution calculated by fluorescence analysis), and the changes in titratable acidity of 10 and 25 days old cotyledons. In the 10 days old cotyledons, C4 and CAM anatomy were evident within the leaf tissue. The cotyledons showed high titratable acid levels but a small CAM induction. In the 25 days old cotyledons, there was a significant acid fluctuation under 7 days of water stress. The overall enzyme activity was reduced in the 10 days old plants, while in the 25 days old plants CAM activity increased under water-stressed conditions. In addition to CAM, the research showed the presence of glycine decarboxylase in the CAM tissue. Thus, it appears both pathways develop simultaneously in the cotyledons but the CAM pathway, due to anatomical constraints, may be slower to develop than the C4 pathway. Cotyledons showed the ancestral Atriplicoid leaf anatomy, which leads to the question: Could a CAM cell be the precursor to the C4 pathway? Further study of this may lead to understanding into the evolution of C4 photosynthesis in the Portulaca.

4.
Ann Rheum Dis ; 78(9): 1160-1166, 2019 09.
Article in English | MEDLINE | ID: mdl-30898837

ABSTRACT

Giant cell arteritis (GCA) represents the most common form of primary systemic vasculitis and is frequently associated with comorbidities related to the disease itself or induced by the treatment. Systematically collected data on disease course, treatment and outcomes of GCA remain scarce. The aim of this EULAR Task Force was to identify a core set of items which can easily be collected by experienced clinicians, in order to facilitate collaborative research into the course and outcomes of GCA. A multidisciplinary EULAR task force group of 20 experts including rheumatologists, internists, epidemiologists and patient representatives was assembled. During a 1-day meeting, breakout groups discussed items from a previously compiled collection of parameters describing GCA status and disease course. Feedback from breakout groups was further discussed. Final consensus was achieved by means of several rounds of email discussions after the meeting. A three-round Delphi survey was conducted to determine a core set of parameters including the level of agreement. 117 parameters were regarded as relevant. Potential items were subdivided into the following categories: General, demographics, GCA-related signs and symptoms, other medical conditions and treatment. Possible instruments and assessment intervals were proposed for documentation of each item. To facilitate implementation of the recommendations in clinical care and clinical research, a minimum core set of 50 parameters was agreed. This proposed core set intends to ensure that relevant items from different GCA registries and databases can be compared for the dual purposes of facilitating clinical research and improving clinical care.


Subject(s)
Biomedical Research/standards , Delivery of Health Care/standards , Giant Cell Arteritis/therapy , Practice Guidelines as Topic , Rheumatology/standards , Societies, Medical , Europe , Humans
5.
Clin Rheumatol ; 38(6): 1767-1772, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30617599

ABSTRACT

INTRODUCTION/OBJECTIVES: Polymyalgia rheumatica (PMR) is a common inflammatory disorder that is usually managed with oral glucocorticoids, which although effective can cause significant adverse events. Support group survey data suggests length of glucocorticoid treatment and managing side effects are key priority areas of management for patients. Recognising that not all patients will access patient support organisations, our objective was to identify priorities for PMR management and research among primary care PMR patients. METHOD: All adults aged ≥ 50 years registered with 150 English general practices who had a first read code for PMR in their medical records in the preceding 3 years were mailed a self-completion questionnaire (n = 704). Survey items included questions regarding patient priorities for PMR management (from a pre-defined list of 10 items) and suggestions for future research (8 items, plus a free-text option), which were developed in collaboration with PMRGCAuk. RESULTS: Five hundred fifty patients responded (78%). The mean (SD) age was 74.1 (8.5) years and 361 (66%) were female. Priority research areas were focused on how to better manage pain, stiffness and fatigue (431, 78%), improving the diagnosis of PMR (393, 71%) and steroid management (342, 62%). CONCLUSIONS: This survey of PMR patients suggests that symptom management, early diagnosis and managing medication are key areas for patients for future research. Researchers and funding organisations should be aware of these priorities if we are to generate research findings that are relevant to the widest range of stakeholders.


Subject(s)
Disease Management , Glucocorticoids/pharmacology , Polymyalgia Rheumatica/drug therapy , Primary Health Care/statistics & numerical data , Research , Aged , Aged, 80 and over , Cross-Sectional Studies , England , Female , Humans , Male , Middle Aged , Surveys and Questionnaires
6.
Clin Rheumatol ; 37(12): 3411-3418, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30066282

ABSTRACT

Polymyalgia rheumatica and giant cell arteritis are relatively common, but under research inflammatory rheumatological conditions. This survey aimed to ascertain the matters in which patients feel they need support with these conditions and appraise how the Charity PMRGCAuk currently supports these needs and could do so in the future. PMRGCAuk members (n = 910) were invited to complete an on-line survey. The survey requested the respondent's history of PMR and or GCA, their perceived priorities for support for people with PMR and or GCA and views on the services already provided by the Charity. A total of 209 people completed the survey. Less than 24% had heard of either PMR or GCA before their diagnosis. Priorities in supporting people with PMR and or GCA included: being on and tapering off glucocorticoids (76.6%), specifically, length of treatment and the risks versus benefits and managing side effects. Respondents generally reported satisfaction with the services currently provided by PMRGCAuk. The support provided by PMRGCAuk is very helpful to members and fills an important gap in provision for people with PMR and or GCA. The areas in which the greatest proportions of participants requested support do not have an evidence base to underpin them. It is incumbent on the research community to address patients' concerns and provide an evidence base where it is required by those affected.


Subject(s)
Giant Cell Arteritis/psychology , Polymyalgia Rheumatica/psychology , Rheumatology/organization & administration , Aged , Cross-Sectional Studies , Female , Giant Cell Arteritis/therapy , Glucocorticoids/therapeutic use , Humans , Inflammation , Male , Middle Aged , Organizations, Nonprofit , Patient Satisfaction , Polymyalgia Rheumatica/therapy , Psychosocial Support Systems , Social Support , Surveys and Questionnaires
7.
Ann Rheum Dis ; 74(10): 1799-807, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26359488

ABSTRACT

Therapy for polymyalgia rheumatica (PMR) varies widely in clinical practice as international recommendations for PMR treatment are not currently available. In this paper, we report the 2015 European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) recommendations for the management of PMR. We used the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology as a framework for the project. Accordingly, the direction and strength of the recommendations are based on the quality of evidence, the balance between desirable and undesirable effects, patients' and clinicians' values and preferences, and resource use. Eight overarching principles and nine specific recommendations were developed covering several aspects of PMR, including basic and follow-up investigations of patients under treatment, risk factor assessment, medical access for patients and specialist referral, treatment strategies such as initial glucocorticoid (GC) doses and subsequent tapering regimens, use of intramuscular GCs and disease modifying anti-rheumatic drugs (DMARDs), as well as the roles of non-steroidal anti-rheumatic drugs and non-pharmacological interventions. These recommendations will inform primary, secondary and tertiary care physicians about an international consensus on the management of PMR. These recommendations should serve to inform clinicians about best practices in the care of patients with PMR.


Subject(s)
Polymyalgia Rheumatica/drug therapy , Algorithms , Antirheumatic Agents/therapeutic use , Biomedical Research/methods , Disease Management , Drug Administration Schedule , Evidence-Based Medicine/methods , Glucocorticoids/administration & dosage , Glucocorticoids/therapeutic use , Humans , International Cooperation , Phytotherapy/methods , Polymyalgia Rheumatica/diagnosis
8.
Arthritis Rheumatol ; 67(10): 2569-80, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26352874

ABSTRACT

Therapy for polymyalgia rheumatica (PMR) varies widely in clinical practice as international recommendations for PMR treatment are not currently available. In this paper, we report the 2015 European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) recommendations for the management of PMR. We used the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology as a framework for the project. Accordingly, the direction and strength of the recommendations are based on the quality of evidence, the balance between desirable and undesirable effects, patients' and clinicians' values and preferences, and resource use. Eight overarching principles and nine specific recommendations were developed covering several aspects of PMR, including basic and follow-up investigations of patients under treatment, risk factor assessment, medical access for patients and specialist referral, treatment strategies such as initial glucocorticoid (GC) doses and subsequent tapering regimens, use of intramuscular GCs and disease modifying anti-rheumatic drugs (DMARDs), as well as the roles of non-steroidal anti-rheumatic drugs and non-pharmacological interventions. These recommendations will inform primary, secondary and tertiary care physicians about an international consensus on the management of PMR. These recommendations should serve to inform clinicians about best practices in the care of patients with PMR.


Subject(s)
Polymyalgia Rheumatica/drug therapy , Antirheumatic Agents/adverse effects , Antirheumatic Agents/therapeutic use , Europe , Glucocorticoids/adverse effects , Glucocorticoids/therapeutic use , Humans , Risk Factors , United States
9.
Eur J Appl Physiol ; 113(3): 775-83, 2013 Mar.
Article in English | MEDLINE | ID: mdl-22971724

ABSTRACT

Exercise is a potent stimulus for release of growth hormone (GH), cortisol, testosterone and prolactin, and prolonged exercise inhibits insulin secretion. These responses seem to be specific to the type of exercise but this has been poorly characterised primarily because they have not been compared during exercise performed by the same individuals. We investigated hormone responses to resistance, sprint and endurance exercise in young men using a repeated measures design in which each subject served as their own control. Eight healthy non-obese young adults (18-25 years) were studied on four occasions in random order: 30-s cycle ergometer sprint (Sprint), 30-min resistance exercise bout (Resistance), 30-min cycle at 70 % VO(2max) (Endurance), and seated rest in the laboratory (Rest). Cortisol, GH, testosterone, prolactin, insulin and glucose concentrations were measured for 60 min after the four different interventions. Endurance and sprint exercise significantly increased GH, cortisol, prolactin and testosterone. Sprint exercise also increased insulin concentrations, whereas this decreased in response to endurance exercise. Resistance exercise significantly increased only testosterone and glucose. Sprint exercise elicited the largest response per unit of work, but the smallest response relative to mean work rate in all hormones. In conclusion, the nature and magnitude of the hormone response were influenced by exercise type, perhaps reflecting the roles of these hormones in regulating metabolism during and after resistance, sprint and endurance exercise.


Subject(s)
Exercise Test/methods , Exercise/physiology , Hormones/blood , Adolescent , Adult , Blood Glucose/analysis , Blood Glucose/metabolism , Hormones/metabolism , Human Growth Hormone/metabolism , Humans , Hydrocortisone/blood , Hydrocortisone/metabolism , Insulin/blood , Insulin/metabolism , Male , Physical Endurance/physiology , Prolactin/blood , Prolactin/metabolism , Resistance Training , Running/physiology , Testosterone/blood , Testosterone/metabolism , Young Adult
10.
Growth Horm IGF Res ; 20(4): 289-94, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20472480

ABSTRACT

Exercise stimulates growth hormone (GH) release, but there are conflicting reports regarding the acute effects of exercise on circulating ghrelin and insulin-like growth factor (IGF) concentrations. This investigation examined (1) the effect of a single sprint on circulating GH, ghrelin and IGF concentrations as well as a marker of IGF-I bioactivity, and (2) whether the number of muscle actions performed during a sprint influences these responses. Seven healthy men completed 3 trials in a random order. In two exercise trials they performed a single 30-s sprint on a cycle ergometer against a resistance equivalent to either 7% (FAST) or 9% (SLOW) of their body mass. In the other they rested in the laboratory (CON). Blood samples were taken pre-, immediately post-, 10 and 30 min post-exercise, and at equivalent times in the CON trial. Total ghrelin concentrations declined after the sprint and were significantly lower after 30 min of recovery than they were pre-exercise (pre-exercise vs. 30 min; FAST, 0.62 (0.19) vs. 0.49 (0.16) microg/L, P<0.001; SLOW, 0.59 (0.15) vs. 0.47 (0.13) microg/L, P<0.001). GH concentrations increased in both exercise trials and were greater in the FAST than the SLOW trial. Serum concentrations of total IGF-I, free IGF-I, total IGF-II, and IGF-I bioactivity did not change after sprinting. In conclusion, sprint exercise suppresses total ghrelin concentrations and stimulates GH release but does not alter IGF concentrations or bioactivity.


Subject(s)
Exercise/physiology , Ghrelin/blood , Human Growth Hormone/blood , Insulin-Like Growth Factor II/metabolism , Insulin-Like Growth Factor I/metabolism , Adult , Humans , Male
11.
Appl Physiol Nutr Metab ; 33(4): 706-12, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18641713

ABSTRACT

Exercise is a potent stimulus for growth hormone (GH) release, although aging appears to attenuate this response. The aim of this study was to investigate GH responses to different exercise stimuli in young and early middle-aged men. Eight men aged 18-25 y and 8 men aged 40-50 y completed 3 trials, at least 7 days apart, in a random order: 30 s cycle-ergometer sprint (sprint), 30 min resistance exercise bout (resistance), 30 min cycle at 70% maximal oxygen consumption (endurance). Blood samples were taken pre-, during, and post-exercise, and area under the GH vs. time curve was calculated for a total of 120 min. Mean blood lactate concentrations and percentage heart rate maximum at which the participants were working were not different between groups in any of the trials. In both groups, blood lactate concentrations were significantly lower in the endurance trial than in the sprint and resistance trials. There were no significant differences in resting GH concentration between groups or trials. GH AUC was significantly greater in the young group than the early middle-aged group, in both sprint (531 (+/-347) vs. 81 (+/-54) microg.L-1 per 120 min, p = 0.003) and endurance trials (842 (+/-616) vs. 177 (+/-137) microg.L-1 per 120 min, p = 0.010). Endurance exercise elicits a greater GH response than sprint and resistance exercise; however, aging per se, factors associated with aging, or an inability to achieve a sufficient absolute exercise intensity results in a smaller GH response to an exercise stimulus in early middle-aged men.


Subject(s)
Exercise/physiology , Growth Hormone/blood , Adolescent , Adult , Age Factors , Exercise Test/statistics & numerical data , Exercise Tolerance/physiology , Heart Rate/physiology , Humans , Lactic Acid/blood , Male , Middle Aged , Oxygen Consumption/physiology , Physical Endurance/physiology , Physical Exertion/physiology , Resistance Training/statistics & numerical data , Time Factors , Young Adult
12.
J Appl Physiol (1985) ; 104(3): 724-8, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18187617

ABSTRACT

A single 30-s sprint is a potent physiological stimulus for growth hormone (GH) release. However, repeated bouts of sprinting attenuate the GH response, possibly due to negative feedback via elevated systemic free fatty acids (FFA). The aim of the study was to use nicotinic acid (NA) to suppress lipolysis to investigate whether serum FFA can modulate the GH response to exercise. Seven nonobese, healthy men performed two trials, consisting of two maximal 30-s cycle ergometer sprints separated by 4 h of recovery. In one trial (NA), participants ingested NA (1 g 60 min before, and 0.5 g 60 and 180 min after sprint 1); the other was a control (Con) trial. Serum FFA was not significantly different between trials before sprint 1 but was significantly lower in the NA trial immediately before sprint 2 [NA vs. Con: mean (SD); 0.08 (0.05) vs. 0.75 (0.34) mmol/l, P < 0.05]. Peak and integrated GH were significantly greater following sprint 2 compared with sprint 1 in the NA trial [peak GH: 23.3 (7.0) vs. 7.7 (11.9) microg/l, P < 0.05; integrated GH: 1,076 (350) vs. 316 (527) microg.l(-1).60 min(-1), P < 0.05] and compared with sprint 2 in the Con trial [peak GH: 23.3 (7.0) vs. 5.2 (2.3) microg/l, P < 0.05; integrated GH: 1,076 (350) vs. 206 (118) microg.l(-1).60 min(-1), P < 0.05]. In conclusion, suppressing lipolysis resulted in a significantly greater GH response to the second of two sprints, suggesting a potential role for serum FFA in negative feedback control of the GH response to repeated exercise.


Subject(s)
Dietary Fats/metabolism , Exercise/physiology , Fatty Acids, Nonesterified/blood , Human Growth Hormone/blood , Hypolipidemic Agents/administration & dosage , Lipolysis/drug effects , Niacin/administration & dosage , Administration, Oral , Adult , Blood Glucose/metabolism , Dietary Fats/administration & dosage , Feedback, Physiological , Humans , Lactic Acid/blood , Male , Running , Time Factors
13.
Methods Mol Biol ; 264: 259-69, 2004.
Article in English | MEDLINE | ID: mdl-15020796

ABSTRACT

Protein-expression profiling of serum is a common approach to the discovery of potential diagnostic and therapeutic markers of disease. Like any other proteome, the serum proteome is characterized by protein expression across a large dynamic range. This single facet requires the employment of fractionation procedures prior to detection of protein. The authors use a combination of conventional column chromatography with array-based chromatography to simplify the serum proteome into subproteomes, thus providing a greater representation of the serum proteome. Robotics is employed to increase the throughput of sample processing. These procedures result in large amounts of data that are analyzed through a series of preprocessing and postprocessing steps. A well-designed serum profiling project can therefore result in the discovery of statistically sound, clinically meaningful protein biomarkers.


Subject(s)
Blood Proteins/chemistry , Protein Array Analysis/methods , Proteome/analysis , Anion Exchange Resins , Blood Proteins/metabolism , Chromatography, Ion Exchange/methods , Gene Expression Profiling , Humans , Protein Array Analysis/instrumentation
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