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O'Connor A, Buffini M, Nugent AP, Kehoe L, Flynn A, Walton J, Kearney J, McNulty B. A food-exchange model for achieving the recommended dietary intakes for saturated fat in Irish children: analysis from the cross-sectional National Children's Food Survey II. Public Health Nutr 2024:1-29. [PMID: 38698582 DOI: 10.1017/s1368980024000971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2024]
Abstract
OBJECTIVE To identify the main foods determining saturated fatty acid (SFA) intakes and model the impact of food exchanges to improve compliance with dietary fat recommendations in Irish children. DESIGN Estimated food and nutrient intakes were obtained from a cross-sectional study, the National Children's Food Survey II. Participants were categorised into low, medium, and high SFA consumers, and the contribution of food categories to SFA intakes were compared. A food-exchange model was developed, whereby a selected range of high SFA foods were exchanged with lower SFA or unsaturated fat alternatives. SETTING Participants were randomly selected from primary schools throughout the Republic of Ireland. PARTICIPANTS A representative sample of 600 Irish children (5-12 years). RESULTS The main determinants of low and high SFA consumers were milk, cheese, and butter. These foods, including snack foods, and meat and meat products, were considered exchangeable foods within the model. Compared with baseline data, modelled intakes for total fat, SFA, monounsaturated fatty acids (MUFA) and trans-fat presented decreases of 3.2, 2.7, 1.6 and <0.1% of total energy (% TE), respectively. Polyunsaturated fatty acid (PUFA), omega 6, omega 3 and alpha-linolenic acid showed increases of 1.0, 0.8, 0.2 and 0.1% TE, respectively. Compliance with total fat, MUFA and trans-fat recommendations remained adequate (100%). Adherence to SFA and PUFA recommendations improved from 18 to 63%, and 80 to 100%, respectively. CONCLUSION The food-exchange model decreased SFA intakes and increased PUFA intakes, suggesting modest dietary changes to children's diets can effectively improve their overall dietary fat profile.
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Affiliation(s)
- Aileen O'Connor
- Institute of Food and Health, School of Agriculture & Food Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - Maria Buffini
- Institute of Food and Health, School of Agriculture & Food Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - Anne P Nugent
- Institute of Food and Health, School of Agriculture & Food Science, University College Dublin, Belfield, Dublin 4, Ireland
- Institute for Global Food Security, Queen's University Belfast, Northern Ireland
| | - Laura Kehoe
- School of Food and Nutritional Sciences, University College Cork, Cork, Ireland
| | - Albert Flynn
- School of Food and Nutritional Sciences, University College Cork, Cork, Ireland
| | - Janette Walton
- Department of Biological Sciences, Cork Institute of Technology, Cork, Ireland
| | - John Kearney
- School of Biological and Health Sciences, Technological University Dublin, Dublin, Ireland
| | - Breige McNulty
- Institute of Food and Health, School of Agriculture & Food Science, University College Dublin, Belfield, Dublin 4, Ireland
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Buffini M, Nugent AP, Walton J, Flynn A, McNulty BA. Erratum: Selenium intakes in the Irish adult population - CORRIGENDUM. J Nutr Sci 2023; 12:e46. [PMID: 37123389 PMCID: PMC10131044 DOI: 10.1017/jns.2023.35] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023] Open
Abstract
[This corrects the article DOI: 10.1017/jns.2023.23.].
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Affiliation(s)
- Maria Buffini
- UCD Institute of Food and Health, School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Republic of Ireland
| | - Anne P Nugent
- UCD Institute of Food and Health, School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Republic of Ireland
- Institute for Global Food Security, Queens University Belfast, Belfast, Northern Ireland, UK
| | - Janette Walton
- School of Food and Nutritional Sciences, University College Cork, Cork, Republic of Ireland
- Department of Biological Sciences, Munster Technological University, Cork, Republic of Ireland
| | - Albert Flynn
- School of Food and Nutritional Sciences, University College Cork, Cork, Republic of Ireland
| | - Breige A McNulty
- UCD Institute of Food and Health, School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Republic of Ireland
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O'Donnell A, Buffini M, Kehoe L, Nugent A, Kearney J, Walton J, Flynn A, McNulty B. Application of a composite scoring protocol to identify factors that contribute to the risk of overweight and obesity in Irish children. Pediatr Obes 2022; 17:e12922. [PMID: 35604281 PMCID: PMC9541128 DOI: 10.1111/ijpo.12922] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 03/08/2022] [Accepted: 04/13/2022] [Indexed: 11/29/2022]
Abstract
BACKGROUND Investigations into the main drivers of childhood obesity are vital to implement effective interventions to halt the global rise in levels. The use of a composite score may help to identify children most at risk of overweight/obesity. OBJECTIVES To investigate the cumulative impact of factors associated with overweight/obesity risk in children. METHODS Data were analysed from the Irish National Children's Food Survey II which included 600 children, aged 5-12-years. The risk factors examined included social class, parental, early life, lifestyle, and dietary components. A composite score was calculated which ranged from 0 (no risk factors for overweight/obesity) to 4 (4 risk factors for overweight/obesity). RESULTS In model 1 (%BF) the four factors associated with overweight/obesity risk were having a parent with overweight/obesity (odds ratio 3.1; 95% confidence interval 1.9-4.8), having a high birth weight of ≥4 kg (2.5; 1.6-3.9), being from a low social class (2.3; 1.4-3.8) and low physical activity (1.9; 1.2-2.8). Children who scored 3-4 points on the composite score had a 10-fold (10.0; 4.2-23.9) increased risk of overweight/obesity compared to those with 0 points, a sevenfold (7.2; 3.9-13.5) increased risk compared to those with 1 point and a threefold (2.6; 1.4-4.8) increased risk compared to those with 2 points, with similar results observed in model 2 (BMI). CONCLUSION The use of a composite score is a beneficial means of identifying children at risk of overweight/obesity and may prove useful in the development of effective interventions to tackle childhood obesity.
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Affiliation(s)
- Aisling O'Donnell
- UCD Institute of Food and Health, School of Agriculture and Food ScienceUniversity College DublinDublinIreland
| | - Maria Buffini
- UCD Institute of Food and Health, School of Agriculture and Food ScienceUniversity College DublinDublinIreland
| | - Laura Kehoe
- School of Food and Nutritional SciencesUniversity College CorkCorkIreland
| | - Anne Nugent
- UCD Institute of Food and Health, School of Agriculture and Food ScienceUniversity College DublinDublinIreland,School of Biological Sciences, Institute for Global Food SecurityQueens University BelfastBelfastNorthern Ireland
| | - John Kearney
- School of Biological & Health SciencesTechnological University DublinDublinIreland
| | - Janette Walton
- Department of Biological SciencesMunster Technological UniversityCorkIreland
| | - Albert Flynn
- School of Food and Nutritional SciencesUniversity College CorkCorkIreland
| | - Breige McNulty
- UCD Institute of Food and Health, School of Agriculture and Food ScienceUniversity College DublinDublinIreland
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O'Donovan CB, Devlin NF, Buffini M, Walton J, Flynn A, Gibney MJ, Nugent AP, McNulty BA. Whole grain intakes in Irish adults: findings from the National Adults Nutrition Survey (NANS). Eur J Nutr 2018; 58:541-550. [PMID: 29353315 DOI: 10.1007/s00394-018-1615-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 01/08/2018] [Indexed: 01/27/2023]
Abstract
PURPOSE Observational studies link high whole grain intakes to reduced risk of many chronic diseases. This study quantified whole grain intakes in the Irish adult population and examined the major contributing sources. It also investigated potential dietary strategies to improve whole grain intakes. METHODS Whole grain intakes were calculated in a nationally representative sample of 1500 Irish adults using data from the most recent national food survey, the National Adult Nutrition Survey (NANS). Food consumption was assessed, at brand level where possible, using a 4-day semi-weighed food diary with whole grain content estimated from labels on a dry matter basis. RESULTS Mean daily whole grain intakes were 27.8 ± 29.4 g/day, with only 19% of the population meeting the quantity-specific recommendation of 48 g per day. Wheat was the highest contributor to whole grain intake at 66%, followed by oats at 26%. High whole grain intakes were associated with higher dietary intakes of fibre, magnesium, potassium, phosphorus, and a higher alternative Mediterranean Diet Score. Whole grain foods were most frequently eaten at breakfast time. Regression analysis revealed that consumption of an additional 10 g of whole grain containing 'ready-to-eat breakfast cereals', 'rice or pastas', or 'breads' each day would increase intake of whole grains by an extra 5, 3.5, and 2.7 g, respectively. CONCLUSIONS This study reveals low intakes of whole grains in Irish adults. Recommending cereals, breads, and grains with higher whole grain content as part of public health campaigns could improve whole grain intakes.
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Affiliation(s)
- Clare B O'Donovan
- UCD Institute of Food and Health, School of Agriculture and Food Science, University College Dublin, Dublin 4, Ireland
| | - Niamh F Devlin
- UCD Institute of Food and Health, School of Agriculture and Food Science, University College Dublin, Dublin 4, Ireland
| | - Maria Buffini
- UCD Institute of Food and Health, School of Agriculture and Food Science, University College Dublin, Dublin 4, Ireland
| | - Janette Walton
- School of Food and Nutritional Sciences, University College Cork, Cork, Ireland.,Department of Biological Sciences, Cork Institute of Technology, Cork, Ireland
| | - Albert Flynn
- School of Food and Nutritional Sciences, University College Cork, Cork, Ireland
| | - Michael J Gibney
- UCD Institute of Food and Health, School of Agriculture and Food Science, University College Dublin, Dublin 4, Ireland
| | - Anne P Nugent
- UCD Institute of Food and Health, School of Agriculture and Food Science, University College Dublin, Dublin 4, Ireland. .,Department of Biological Sciences, Institute for Global Food Security, Queens University Belfast, Belfast, Ireland.
| | - Breige A McNulty
- UCD Institute of Food and Health, School of Agriculture and Food Science, University College Dublin, Dublin 4, Ireland
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Buffini M, Goscinny S, Van Loco J, Nugent AP, Walton J, Flynn A, Gibney MJ, McNulty BA. Dietary intakes of six intense sweeteners by Irish adults. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2017; 35:425-438. [PMID: 29210609 DOI: 10.1080/19440049.2017.1411619] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
This research investigated the intakes of six intense sweeteners: acesulfame-K (E950), aspartame (E951), cyclamate (E952), saccharin (E954), sucralose (E955), and steviol glycosides (E960) in the diets of Irish adults, using data from the National Adult Nutrition Survey. A food label survey that included products currently available on the Irish market supplemented the analysis. Sweetener intakes were investigated using three different exposure scenarios; beginning with a crude assessment which assumed that all foods permitted to contain the additives of interest always did contain them, and at their maximum permitted level (Tier 1). Refined assessments estimated intakes of the six sweeteners using food consumption data up to brand level with additive occurrence data from a survey of products currently available on the Irish market (Tier 2) and sweetener concentration data (Tier 3). Results of all exposure assessment scenarios demonstrate that intakes of each of the sweeteners of interest by the total population were below the relevant ADI level (mg kg-1 bodyweight-1), even by high consumers (P99). The three sweeteners consumed in highest amounts were acesulfame-k, aspartame, and sucralose. The main sources of these sweeteners in the diet were 'cider and perry', 'energy reduced and no added sugar (ER and NAS) carbonated flavoured drinks', 'table-top sweeteners', 'dairy products', 'solid food supplements', and 'sauces'. Intakes of the six intense sweeteners are currently not a concern among Irish adults. However, exposure to these chemicals should be monitored on a regular basis due to evolving market and consumption patterns.
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Affiliation(s)
- Maria Buffini
- a School of Agriculture and Food Science , University College Dublin, UCD Institute of Food and Health , Belfield , Ireland
| | - Séverine Goscinny
- b Belgian Scientific Institute of Public Health, Department of Food , Medicines and Consumer Safety, Service of Consumer Safety, Scientific Institute of Public Health , Brussels , Belgium
| | - Joris Van Loco
- b Belgian Scientific Institute of Public Health, Department of Food , Medicines and Consumer Safety, Service of Consumer Safety, Scientific Institute of Public Health , Brussels , Belgium
| | - Anne P Nugent
- a School of Agriculture and Food Science , University College Dublin, UCD Institute of Food and Health , Belfield , Ireland
| | - Janette Walton
- c School of Food and Nutritional Sciences , University College Cork , Cork , Ireland
| | - Albert Flynn
- c School of Food and Nutritional Sciences , University College Cork , Cork , Ireland
| | - Michael J Gibney
- a School of Agriculture and Food Science , University College Dublin, UCD Institute of Food and Health , Belfield , Ireland
| | - Breige A McNulty
- a School of Agriculture and Food Science , University College Dublin, UCD Institute of Food and Health , Belfield , Ireland
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Devane LA, Lucking E, Evers J, Buffini M, Scott SM, Knowles CH, O'Connell PR, Jones JFX. Altered defaecatory behaviour and faecal incontinence in a video-tracked animal model of pudendal neuropathy. Colorectal Dis 2017; 19:O162-O167. [PMID: 28319326 DOI: 10.1111/codi.13664] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 12/19/2016] [Indexed: 02/08/2023]
Abstract
AIM The aim was to develop a behavioural animal model of faecal continence and assess the effect of retro-uterine balloon inflation (RBI) injury. RBI in the rat causes pudendal neuropathy, a risk factor for obstetric related faecal incontinence in humans. METHOD Video-tracking of healthy rats (n = 12) in a cage containing a latrine box was used to monitor their defaecatory behaviour index (DBI) over 2 weeks. The DBI (range 0-1) was devised by dividing the defaecation rate (pellets per hour) outside the latrine by that of the whole cage. A score of 0 indicates all pellets were deposited in the latrine. Subsequently, the effects of RBI (n = 19), sham surgery (n = 4) and colostomy (n = 2) were determined by monitoring the DBI for 2 weeks preoperatively and 3 weeks postoperatively. RESULTS The DBI for healthy rats was 0.1 ± 0.03 with no significant change over 2 weeks (P = 0.71). In the RBI group, 13 of 19 rats (68%) showed no significant change in DBI postoperatively (0.08 ± -0.05 vs 0.11 ± -0.07) while in six rats the DBI increased from 0.16 ± -0.09 to 0.46 ± 0.23. The negative control, sham surgery, did not significantly affect the DBI (0.09 ± 0.06 vs 0.08 ± 0.04, P = 0.14). The positive control, colostomy, increased the DBI from 0.26 ± 0.03 to 0.86 ± 0.08. CONCLUSIONS This is the first study showing a quantifiable change in defaecatory behaviour following injury in an animal model. This model of pudendal neuropathy affects continence in 32% of rats and provides a basis for research on interventions for incontinence.
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Affiliation(s)
- L A Devane
- School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
| | - E Lucking
- School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
| | - J Evers
- School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
| | - M Buffini
- School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
| | - S M Scott
- National Bowel Research Centre (NBRC) and GI Physiology Unit, Queen Mary University of London, London, UK
| | - C H Knowles
- National Bowel Research Centre (NBRC) and GI Physiology Unit, Queen Mary University of London, London, UK
| | - P R O'Connell
- School of Medicine and Medical Science, University College Dublin, Dublin, Ireland.,Centre for Colorectal Disease, St Vincent's University Hospital, Dublin, Ireland
| | - J F X Jones
- School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
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Evers J, Buffini M, Craven S, O'Connell PR, Jones JFX. Is there a nitrergic modulation of the rat external anal sphincter? Exp Physiol 2012; 98:397-404. [PMID: 22872659 DOI: 10.1113/expphysiol.2012.067413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Nitric oxide is known to relax the internal anal sphincter, but its effect on the external anal sphincter (EAS) is unknown. The aim of this study was to investigate whether there is a nitrergic nerve plexus that modulates the EAS, similar to that found in oesophageal striated muscle. An in vitro ring preparation of rat anal canal was used to evaluate the effects of the nitric oxide synthase inhibitor N(ω)-nitro-L-arginine (L-NNA) and the NO donor sodium nitroprusside (SNP) on the EAS in conditions of neuromuscular blockade and the effect of SNP on nerve-evoked contractions. Immunohistological experiments were conducted to determine whether the neuronal isoform of nitric oxide synthase (nNOS) is present in the EAS. During direct muscle stimulation neither L-NNA (P = 0.32) nor SNP (P = 0.19) significantly changed the EF(50), which is the frequency at which 50% of maximal contraction is reached, compared with a time-dependent control. Nerve-evoked contractions were also not altered by addition of SNP to the tissue bath. Immunohistohistological experiments clearly showed co-localization of nNOS-positive nerve fibres at motor endplates of the oesophagus but not in the EAS. The internal anal sphincter was richly innervated by nitrergic fibres, but these did not extend into the EAS. In conclusion, there are no nitrergic motor fibres innervating the EAS, neurotransmission at the motor endplates is not affected by NO, and NO does not affect muscle force directly in conditions of neuromuscular blockade. There is, therefore, no evidence that EAS contraction is directly modulated by NO or by pudendal nitrergic fibres or diffusion from neighbouring nitrergic plexuses of the anal canal.
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Affiliation(s)
- J Evers
- School of Medicine and Medical Science, Health Science Centre, University College Dublin, Dublin, Ireland
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Buffini M, O'Halloran KD, O'Herlihy C, O'Connell PR, Jones JFX. Comparison of the motor discharge to the voluntary sphincters of continence in the rat. Neurogastroenterol Motil 2012; 24:e175-84. [PMID: 22235853 DOI: 10.1111/j.1365-2982.2011.01856.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND The rat external anal sphincter (EAS) and external urethral sphincter (EUS) are voluntary muscles of continence that can display similar synchronous electromyographic (EMG) activity patterns. However, the two sphincters are quite different in structure and function. The EUS is a fast twitch muscle and contains fibers expressing type 2B myosin. In contrast, the EAS exhibits slower kinetics and lacks type 2B fibers. This striking contrast in kinetics and fiber type profiles may be shaped by differences in the basal motor drive that each sphincter receives. METHODS A double EMG approach was used to obtain spontaneously active single motor unit action potentials from the EUS and EAS simultaneously and compare their basal discharge frequencies in urethane anaesthetized rats. KEY RESULTS The basal firing rates of motor units of the EUS and EAS were not significantly different (3.9 ± 0.9 Hz vs. 3.1 ± 1.6 Hz, respectively, n = 7 animals, P = 0.32, paired Student's t-test). However, auto-correlogram analysis showed that EUS is driven by neurons with faster instantaneous firing frequencies: 30.5 ± 2.4 Hz vs 14.3 ± 0.9 Hz in the EAS (P = 0.03, paired Student's t-test). CONCLUSIONS & INFERENCES The oscillator(s) driving the EUS operate(s) at a frequency twice that of the EAS. This may explain the presence of type 2B fibers in the EUS. In the inter-micturition periods no cross correlation was found in motor discharge to the sphincters suggesting that the two muscles do not share a common central drive to sustain the continent tonus of the two outlet tracts.
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Affiliation(s)
- M Buffini
- School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
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Buffini M, O'Halloran KD, O'Herlihy C, O'Connell R, Jones JFX. Comparison of the contractile properties, oxidative capacities and fibre type profiles of the voluntary sphincters of continence in the rat. J Anat 2010; 217:187-95. [PMID: 20626497 DOI: 10.1111/j.1469-7580.2010.01263.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The external urethral sphincter (EUS) and external anal sphincter (EAS) are the principal voluntary striated muscles that sustain continence of urine and faeces. In light of their common embryological origin, shared tonic sphincteric action and synchronized electrical activity in vivo, it was expected that they would exhibit similar physiological and structural properties. However, the findings of this study using paired observations of both sphincters isolated from the rat show clearly that this is not the case. The anal sphincter is much more fatigable than the urethral sphincter. On completion of a fatigue protocol, the amplitude of the last twitch of the EAS had declined to 42 +/- 3% of the first twitch, whereas the last twitch of the EUS was almost identical to that of the first (95 +/- 3%). Immunocytochemical detection of myosin heavy-chain isoforms showed that this difference was not due to the presence of more slow-twitch oxidative type 1 fibres in the EUS compared with the EAS (areal densities 4 +/- 1% and 5 +/- 1%, respectively; P = 0.35). In addition, the fatigue difference was not explained by a greater contribution to force production by fast oxidative type 2A fibres in the urethral sphincter. In fact, the anal sphincter contained a higher areal density of type 2A fibres (56 +/- 5% vs. 37 +/- 4% in the EUS, P = 0.017). The higher oxidative capacity of the EUS, measured histochemically, explained its fatigue resistance. These results were surprising because the fatigue-resistant urethral muscle exhibited faster single-twitch contraction times compared with the anal sphincter (56 +/- 0.87 ms vs. 72.5 +/- 1.16 ms, P < 0.001). Neither sphincter expressed the type 2X myosin isoform but the fast-twitch isoform type 2B was found exclusively in the EUS (areal density 16 +/- 2%). The type 2B fibres of the EUS were small (diameter 19.5 +/- 0.4 mum) in comparison to typical type 2B fibres of other muscles. As a whole the EUS is a more oxidative than glycolytic muscle. In conclusion, analysis of the twitch mechanics and fatigue of two sphincters showed that the EUS contained more fatigue-resistant muscle fibres compared with the EAS.
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Affiliation(s)
- Maria Buffini
- School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
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Abstract
BACKGROUND Pudendal nerve injury during childbirth may result in external anal sphincter (EAS) atrophy. Recently, balloon compression of the pelvic side wall has been shown to result in EAS atrophy in an experimental model. The aim of this study was to determine whether other sphincters of continence are similarly affected. METHOD Sixteen adult female virgin Wistar rats (eight controls) were studied 4 weeks after surgery. Anal and urethral canals were dissected, snap frozen and sectioned using a cryostat (100 microm thickness). Masses of EAS, internal anal sphincter (IAS) and external urethral sphincter (EUS) were calculated stereologically and stained with succinate dehydrogenase histochemistry to differentiate striated from smooth muscle. Sphincter length was determined and total sphincter mass calculated. Data were analysed with an unpaired Student's t-test. RESULTS Atrophy of EAS (30.9 +/- 1.7 to 21.3 +/- 1.7 mg/ kg, P = 0.001), IAS (98.1 +/- 11.3 to 67.1 +/- 5.0 mg/kg, P = 0.01) and EUS (9.6 +/- 0.98 to 7.4 +/- 0.8 mg/kg, P = 0.05) was found 4 weeks after the injury. CONCLUSION In an experimental model of obstetric pudendal nerve injury, significant atrophy of striated and smooth muscle sphincters of continence occurs and may contribute to altered continence following vaginal childbirth.
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Affiliation(s)
- M Banahan
- School of Medicine and Medical Science, University College Dublin, Belfield, Dublin 4, Ireland
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Doran P, Dowling P, Donoghue P, Buffini M, Ohlendieck K. Reduced expression of regucalcin in young and aged mdx diaphragm indicates abnormal cytosolic calcium handling in dystrophin-deficient muscle. Biochim Biophys Acta 2006; 1764:773-85. [PMID: 16483859 DOI: 10.1016/j.bbapap.2006.01.007] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2005] [Revised: 12/09/2005] [Accepted: 01/02/2006] [Indexed: 11/16/2022]
Abstract
The cytosolic Ca2+ -binding protein regucalcin is involved in intracellular signaling and present in high abundance in the liver. Here, we could show by comparative mass spectrometry-based proteomics screening of normal versus dystrophic fibres that regucalcin of 33.9 kDa and pI5.2 also exists in diaphragm muscle. Since the expression of sarcolemmal Ca2+ -leak channels and luminal Ca2+ -binding elements is altered in dystrophin-deficient muscle, we initiated this study in order to determine whether additional soluble muscle proteins involved in Ca2+ -handling are affected in muscular dystrophy. Following separation by two-dimensional gel electrophoresis, the spot pattern of the normal versus the mdx diaphragm muscle proteome was evaluated by densitometry. The expression levels of 20 major protein spots were shown to change and their identity determined by mass spectrometry. A 2-fold reduction of regucalcin in mdx diaphragm, as well as in dystrophic limb muscle and heart, was confirmed by immunoblotting in both young and aged mdx mice. The results from our proteomics analysis of dystrophic diaphragm support the concept that abnormal Ca2+ -handling is involved in x-linked muscular dystrophy. The reduction in key Ca2+ -handling proteins may result in an insufficient maintenance of Ca2+ -homeostasis and an abnormal regulation of Ca2+ -dependent enzymes resulting in disturbed intracellular signaling mechanisms in dystrophinopathies.
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Affiliation(s)
- Philip Doran
- Department of Biology, National University of Ireland, Maynooth, Co. Kildare, Ireland
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