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1.
Scand J Med Sci Sports ; 33(12): 2470-2481, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37787091

ABSTRACT

Studies examining the effect of protein (PRO) feeding on post resistance exercise (RE) muscle protein synthesis (MPS) have primarily been performed in men, and little evidence is available regarding the quantity of PRO required to maximally stimulate MPS in trained women following repeated bouts of RE. We therefore quantified acute (4 h and 8 h) and extended (24 h) effects of two bouts of resistance exercise, alongside protein-feeding, in women, and the PRO requirement to maximize MPS. Twenty-four RE trained women (26.6 ± 0.7 years, mean ± SEM) performed two bouts of whole-body RE (3 × 8 repetitions/maneuver at 75% 1-repetition maximum) 4 h apart, with post-exercise ingestion of 15 g, 30 g, or 60 g whey PRO (n = 8/group). Saliva, venous blood, and a vastus lateralis muscle biopsy were taken at 0 h, 4 h, 8 h, and 24 h post-exercise. Plasma leucine and branched chain amino acids were quantified using gas chromatography mass spectrometry (GC-MS) after ingestion of D2 O. Fifteen grams PRO did not alter plasma leucine concentration or myofibrillar synthetic rate (MyoFSR). Thirty and sixty grams PRO increased plasma leucine concentration above baseline (105.5 ± 5.3 µM; 120.2 ± 7.4 µM, respectively) at 4 h (151.5 ± 8.2 µM, p < 0.01; 224.8 ± 16.0 µM, p < 0.001, respectively) and 8 h (176.0 ± 7.3 µM, p < 0.001; 281.7 ± 21.6 µM, p < 0.001, respectively). Ingestion of 30 g PRO increased MyoFSR above baseline (0.068 ± 0.005%/h) from 0 to 4 h (0.140 ± 0.021%/h, p < 0.05), 0 to 8 h (0.121 ± 0.012%/h, p < 0.001), and 0 to 24 h (0.099 ± 0.011%/h, p < 0.01). Ingestion of 60 g PRO increased MyoFSR above baseline (0.063 ± 0.003%/h) from 0 to 4 h (0.109 ± 0.011%/h, p < 0.01), 0 to 8 h (0.093 ± 0.008%/h, p < 0.01), and 0 to 24 h (0.086 ± 0.006%/h, p < 0.01). Post-exercise ingestion of 30 g or 60 g PRO, but not 15 g, acutely increased MyoFSR following two consecutive bouts of RE and extended the anabolic window over 24 h. There was no difference between the 30 g and 60 g responses.


Subject(s)
Resistance Training , Male , Humans , Female , Leucine/metabolism , Leucine/pharmacology , Whey Proteins , Muscle, Skeletal/metabolism , Muscle Proteins/metabolism
2.
Pediatr Surg Int ; 38(4): 617-621, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35175403

ABSTRACT

AIM: Several studies have addressed the long-term functional, psychosexual and psychosocial outcomes following sacrococcygeal teratoma (SCT) excision. It is well reported that the classical chevron incision and reconstruction can leave a cosmetically unsatisfactory result; however, there is little in the literature focussed on improving this outcome. In our institution the preference is to perform a midline reconstruction, where possible, this is felt to improve appearance without compromising the oncological or functional outcome. The aim of this study was to evaluate patient-perceived cosmetic outcomes of the midline reconstruction. METHODS: All patients undergoing surgery for SCT between 2007 and 2020 were included in the study. Patient demographics, operation type, functional outcome and recurrence were all recorded. The primary outcome measure was patient/parent satisfaction with the cosmetic appearance. This was assessed using both qualitative and quantitative methodologies. Following ethical approval parents were asked questions from two existing validated patient outcome questionnaires: "Patient and Observer Scar Assessment Scale" (POSAS) v2.0 and the "Patient Scar Assessment Questionnaire". RESULTS: Thirty-two patients underwent surgery at our institution for SCT during the study period. Twenty-four had a posterior approach with midline reconstruction, two laparotomy and excision (excluded from this study) and six had a combined approach. Median follow-up was 35 months (8.5-96 months). There were no recurrences. 4/30 (13%) have persistent urological symptoms, and 1/30 (3%) has constipation requiring bowel management. Questionnaires were sent to 26/30 families with a 77% return rate. Median total score was 11 (7.4-17.5) on a 60-point scale (6, as normal skin, 60, worst imaginable scar). Twenty (95%) reported that the scar never affects the child's activities and 15 (71%) said they are "not at all" conscious of the scar. CONCLUSION: Scars can lead to an array of cosmetic, functional, and psychological consequences and as such consideration needs to be given to scarring following surgery for sacrococcygeal teratomas. This study demonstrates that a midline reconstruction produces a cosmetically favourable outcome. We, therefore, recommend where appropriate a midline reconstruction should be considered for SCT.


Subject(s)
Pelvic Neoplasms , Teratoma , Child , Cicatrix , Humans , Patient Satisfaction , Sacrococcygeal Region/surgery , Surveys and Questionnaires , Teratoma/surgery
3.
Anaesthesia ; 76(10): 1308-1315, 2021 10.
Article in English | MEDLINE | ID: mdl-33878803

ABSTRACT

In this article, we describe an extension of general anaesthesia - beyond facilitating surgery - to the relief of suffering during dying. Some refractory symptoms at the end of life (pain, delirium, distress, dyspnoea) might be managed by analgesia, but in high doses, adverse effects (e.g. respiratory depression) can hasten death. Sedation may be needed for agitation or distress and can be administered as continuous deep sedation (also referred to as terminal or palliative sedation) generally using benzodiazepines. However, for some patients these interventions are not enough, and others may express a clear desire to be completely unconscious as they die. We summarise the historical background of an established practice that we refer to as 'general anaesthesia in end-of-life care'. We discuss its contexts and some ethical and legal issues that it raises, arguing that these are largely similar issues to those already raised by continuous deep sedation. To be a valid option, general anaesthesia in end-of-life care will require a clear multidisciplinary framework and consensus practice guidelines. We see these as an impending development for which the specialty should prepare. General anaesthesia in end-of-life care raises an important debate about the possible role of anaesthesia in the relief of suffering beyond the context of surgical/diagnostic interventions.


Subject(s)
Anesthesia, General/methods , Anesthesiology/methods , Terminal Care/methods , Humans
4.
Am J Physiol Endocrinol Metab ; 318(6): E943-E955, 2020 06 01.
Article in English | MEDLINE | ID: mdl-32369414

ABSTRACT

Myokines, such as irisin, have been purported to exert physiological effects on skeletal muscle in an autocrine/paracrine fashion. In this study, we aimed to investigate the mechanistic role of in vivo fibronectin type III domain-containing 5 (Fndc5)/irisin upregulation in muscle. Overexpression (OE) of Fndc5 in rat hindlimb muscle was achieved by in vivo electrotransfer, i.e., bilateral injections of Fndc5 harboring vectors for OE rats (n = 8) and empty vector for control rats (n = 8). Seven days later, a bolus of D2O (7.2 mL/kg) was administered via oral gavage to quantify muscle protein synthesis. After an overnight fast, on day 9, 2-deoxy-d-glucose-6-phosphate (2-DG6P; 6 mg/kg) was provided during an intraperitoneal glucose tolerance test (2 g/kg) to assess glucose handling. Animals were euthanized, musculus tibialis cranialis muscles and subcutaneous fat (inguinal) were harvested, and metabolic and molecular effects were evaluated. Muscle Fndc5 mRNA increased with OE (~2-fold; P = 0.014), leading to increased circulating irisin (1.5 ± 0.9 to 3.5 ± 1.2 ng/mL; P = 0.049). OE had no effect on protein anabolism or mitochondrial biogenesis; however, muscle glycogen was increased, along with glycogen synthase 1 gene expression (P = 0.04 and 0.02, respectively). In addition to an increase in glycogen synthase activation in OE (P = 0.03), there was a tendency toward increased glucose transporter 4 protein (P = 0.09). However, glucose uptake (accumulation of 2-DG6P) was identical. Irisin elicited no endocrine effect on mitochondrial biogenesis or uncoupling proteins in white adipose tissue. Hindlimb overexpression led to physiological increases in Fndc5/irisin. However, our data indicate limited short-term impacts of irisin in relation to muscle anabolism, mitochondrial biogenesis, glucose uptake, or adipose remodeling.


Subject(s)
Fibronectins/genetics , Muscle, Skeletal/metabolism , Subcutaneous Fat/metabolism , Animals , Deoxyglucose/metabolism , Deuterium Oxide , Electroporation , Fibronectins/metabolism , Gene Expression , Glucose/metabolism , Glucose Tolerance Test , Glucose Transporter Type 4/genetics , Glucose-6-Phosphate/analogs & derivatives , Glucose-6-Phosphate/metabolism , Glycogen/metabolism , Glycogen Synthase/genetics , Glycogen Synthase/metabolism , Hindlimb , Male , Mitochondrial Uncoupling Proteins/genetics , Organelle Biogenesis , Protein Biosynthesis , RNA, Messenger/metabolism , Rats
5.
Am J Physiol Endocrinol Metab ; 313(6): E681-E689, 2017 12 01.
Article in English | MEDLINE | ID: mdl-28811296

ABSTRACT

Current methods to quantify in vivo RNA dynamics are limited. Here, we developed a novel stable isotope (D2O) methodology to quantify RNA synthesis (i.e., ribosomal biogenesis) in cells, animal models, and humans. First, proliferating C2C12 cells were incubated in D2O-enriched media and myotubes ±50 ng/ml IGF-I. Second, rat quadriceps (untrained, n = 9; 7-wk interval-"like" training, n = 13) were collected after ~3-wk D2O (70 atom %) administration, with body-water enrichment monitored via blood sampling. Finally, 10 (23 ± 1 yr) men consumed 150-ml D2O followed by 50 ml/wk and undertook 6-wk resistance exercise (6 × 8 repetitions, 75% 1-repetition maximum 3/wk) with body-water enrichment monitored by saliva sampling and muscle biopsies (for determination of RNA synthesis) at 0, 3, and 6 wk. Ribose mole percent excess (r-MPE) from purine nucleotides was analyzed via GC-MS/MS. Proliferating C2C12 cell r-MPE exhibited a rise to plateau, whereas IGF-I increased myotube RNA from 76 ± 3 to 123 ± 3 ng/µl and r-MPE by 0.39 ± 0.1% (both P < 0.01). After 3 wk, rat quadriceps r-MPE had increased to 0.25 ± 0.01% (P < 0.01) and was greater with running exercise (0.36 ± 0.02%; P < 0.01). Human muscle r-MPE increased to 0.06 ± 0.01 and 0.13 ± 0.02% at 3/6 wk, respectively, equating to synthesis rates of ~0.8%/day, increasing with resistance exercise to 1.7 ± 0.3%/day (P < 0.01) and 1.2 ± 0.1%/day (P < 0.05) at 3/6 wk, respectively. Therefore, we have developed and physiologically validated a novel technique to explore ribosomal biogenesis in a multimodal fashion.


Subject(s)
Biomarkers/metabolism , Deuterium Oxide , Quadriceps Muscle/metabolism , RNA/biosynthesis , Ribosomes/metabolism , Animals , Cell Line , Female , Humans , Male , Mice , Physical Conditioning, Animal , Rats , Resistance Training , Ribose/metabolism , Tandem Mass Spectrometry , Young Adult
6.
Scand J Med Sci Sports ; 27(1): 4-25, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27263489

ABSTRACT

The applications of Western/immunoblotting (WB) techniques have reached multiple layers of the scientific community and are now considered routine procedures in the field of physiology. This is none more so than in relation to skeletal muscle physiology (i.e., resolving the mechanisms underpinning adaptations to exercise). Indeed, the inclusion of WB data is now considered an essential aspect of many such physiological publications to provide mechanistic insight into regulatory processes. Despite this popularity, and due to the ubiquitous and relatively inexpensive availability of WB equipment, the quality of WB in publications and subsequent analysis and interpretation of the data can be variable, perhaps resulting in spurious conclusions. This may be due to poor laboratory technique and/or lack of comprehension of the critical steps involved in WB and what quality control procedures should be in place to ensure robust data generation. The present review aims to provide a detailed description and critique of WB procedures and technicalities, from sample collection through preparation, blotting and detection, to analysis of the data collected. We aim to provide the reader with improved expertise to critically conduct, evaluate, and troubleshoot the WB process, to produce reproducible and reliable blots.


Subject(s)
Blotting, Western/methods , Muscle, Skeletal/metabolism , Blotting, Western/standards , Data Accuracy , Humans , Physiology , Specimen Handling/methods , Specimen Handling/standards
9.
Prenat Diagn ; 34(1): 42-9, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24122837

ABSTRACT

OBJECTIVE: The objective of this study was to explore the attitudes of obstetricians in Australia, New Zealand and the UK towards prenatally diagnosed trisomy 18 (T18). METHOD: Obstetricians were contacted by email and invited to participate in an anonymous electronic survey. RESULTS: Survey responses were obtained from 1018/3717 (27%) practicing obstetricians/gynaecologists. Most (60%) had managed a case of T18 in the last 2 years. Eighty-five per cent believed that T18 was a 'lethal malformation', although 38% expected at least half of liveborn infants to survive for more than 1 week. Twenty-one per cent indicated that a vegetative existence was the best developmental outcome for surviving children. In a case of antenatally diagnosed T18, 95% of obstetricians would provide a mother with the option of termination. If requested, 99% would provide maternal-focused obstetric care (aimed at maternal wellbeing rather than fetal survival), whereas 80% would provide fetal-oriented obstetric care (to maximise fetal survival). Twenty-eight per cent would never discuss the option of caesarean; 21% would always discuss this option. Management options, attitudes and knowledge of T18 were associated with location, practice type, gender and religion of obstetricians. CONCLUSION: There is variability in obstetricians' attitudes towards T18, with significant implications for management of affected pregnancies.


Subject(s)
Attitude of Health Personnel , Obstetrics/methods , Perinatal Care , Physicians , Trisomy , Abortion, Induced , Australia , Chromosomes, Human, Pair 18 , Congenital Abnormalities/genetics , Female , Humans , Male , New Zealand , Practice Patterns, Physicians' , Pregnancy , Prenatal Diagnosis , Religion , Sex Factors , Surveys and Questionnaires , Trisomy 18 Syndrome , United Kingdom
10.
Acta Anaesthesiol Scand ; 58(2): 185-91, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24410107

ABSTRACT

BACKGROUND: Cognitive problems early after surgery are often considered transient in nature. Neuropsychological performance and its relation to other recovery parameters have rarely been systematically assessed during this period. METHODS: A subanalysis of the Post-operative Quality of Recovery Scale (PQRS) feasibility study included patients who completed the PQRS on day 3, and were categorised as recovered or not recovered in the cognitive domain using the revised scoring method. RESULTS: Of the 449 patients included in this paper, 388 (86.4%) recovered in the cognitive domain and 61 (13.6%) had not recovered at 3 days. Cognitive recovery in the early post-operative time points up to day 1 was significantly lower in patients who had not recovered at day 3 (P < 0.001). Of those not recovered on day 3, 59.1% had recovered on day 1, but lapsed to non-recovery on day 3. The non-recovered group demonstrated less recovery in the physiological (P = 0.019), activity of daily living (P = 0.049) and nociceptive (P = 0.033) domains, but no difference was found in the emotive domain. The non-recovered group had a higher incidence of major surgery (P = 0.021), a higher proportion of patients with difficulty eating (4.9% vs. 0.5%, P = 0.002 and a clinically unimportant but lower temperature (36.6° vs. 36.4°C, P = 0.010). CONCLUSION: Failure of cognitive recovery is reasonably common 3 days after surgery, can fluctuate and is associated with poorer early recovery in the activities of daily living, nociceptive and physiological domains.


Subject(s)
Anesthesia Recovery Period , Cognition/physiology , Neuropsychological Tests , Postoperative Period , Activities of Daily Living , Adult , Aged , Anesthesia, General , Executive Function , Feasibility Studies , Female , Humans , Male , Mental Recall/physiology , Middle Aged , Nociception/physiology , Orientation/physiology , Risk Factors , Wechsler Scales
11.
J Physiol ; 591(11): 2911-23, 2013 Jun 01.
Article in English | MEDLINE | ID: mdl-23551944

ABSTRACT

Maintenance of skeletal muscle mass is contingent upon the dynamic equilibrium (fasted losses-fed gains) in protein turnover. Of all nutrients, the single amino acid leucine (Leu) possesses the most marked anabolic characteristics in acting as a trigger element for the initiation of protein synthesis. While the mechanisms by which Leu is 'sensed' have been the subject of great scrutiny, as a branched-chain amino acid, Leu can be catabolized within muscle, thus posing the possibility that metabolites of Leu could be involved in mediating the anabolic effect(s) of Leu. Our objective was to measure muscle protein anabolism in response to Leu and its metabolite HMB. Using [1,2-(13)C2]Leu and [(2)H5]phenylalanine tracers, and GC-MS/GC-C-IRMS we studied the effect of HMB or Leu alone on MPS (by tracer incorporation into myofibrils), and for HMB we also measured muscle proteolysis (by arteriovenous (A-V) dilution). Orally consumed 3.42 g free-acid (FA-HMB) HMB (providing 2.42 g of pure HMB) exhibited rapid bioavailability in plasma and muscle and, similarly to 3.42 g Leu, stimulated muscle protein synthesis (MPS; HMB +70% vs. Leu +110%). While HMB and Leu both increased anabolic signalling (mechanistic target of rapamycin; mTOR), this was more pronounced with Leu (i.e. p70S6K1 signalling 90 min vs. 30 min for HMB). HMB consumption also attenuated muscle protein breakdown (MPB; -57%) in an insulin-independent manner. We conclude that exogenous HMB induces acute muscle anabolism (increased MPS and reduced MPB) albeit perhaps via distinct, and/or additional mechanism(s) to Leu.


Subject(s)
Leucine/pharmacology , Muscle, Skeletal/metabolism , Protein Biosynthesis/drug effects , Proteolysis/drug effects , Valerates/pharmacology , Administration, Oral , Humans , Leucine/administration & dosage , Leucine/pharmacokinetics , Male , Tissue Distribution , Valerates/administration & dosage , Valerates/pharmacokinetics , Young Adult
12.
BJOG ; 119(11): 1302-8, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22827258

ABSTRACT

Prenatally diagnosed abnormalities that are associated with death in the newborn period are often referred to as 'lethal malformations'. Yet, for many of the commonly described lethal malformations long-term survival is possible if supportive interventions are provided. In this paper we analyse and review fetal or congenital lethal abnormalities. The designation 'lethal' overlaps with the concept of 'medical futility'. The term is used for a heterogenous group of conditions, and hinders clear communication and counselling. We argue that the term should be avoided, and propose in its place a set of key questions that should be addressed by counselling.


Subject(s)
Congenital Abnormalities/diagnosis , Ethical Analysis , Fetus/abnormalities , Prenatal Diagnosis/ethics , Counseling , Female , Fetal Death , Humans , Infant Mortality , Infant, Newborn , Medical Futility , Pregnancy , Prognosis
13.
Anaesthesia ; 67(12): 1375-85, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23130725

ABSTRACT

The practice of anaesthesia was revolutionised by the ideas of Archie Brain. The routine use of a facemask to manage the airway was not a hands-free technique, despite the development of various harnesses, and made adequate record-keeping difficult. The tracheal tube was associated with some morbidity, which some felt was unsuitable for day surgery. Brain developed an airway management device that was less stressful to the patient than tracheal intubation, and was, however, as safe as using a facemask and airway. Brain also hoped his device would function for cases where mask ventilation was particularly difficult and thus give anaesthetists a safer alternative to a complex intubation, especially in emergency scenarios.


Subject(s)
Laryngeal Masks/history , Equipment Design/history , History, 20th Century , Humans , London , Male , United States
14.
Sci Rep ; 12(1): 19273, 2022 11 11.
Article in English | MEDLINE | ID: mdl-36369511

ABSTRACT

Higher plasma leucine, isoleucine and valine (BCAA) concentrations are associated with diabetes, obesity and insulin resistance (IR). Here, we evaluated the effects of 6-weeks very-low calorie diet (VLCD) upon fasting BCAA in overweight (OW) non-diabetic men, to explore associations between circulating BCAA and IR, before and after a weight loss intervention. Fasting plasma BCAAs were quantified in an OW (n = 26; BMI 32.4 ± 3 kg/m2; mean age 44 ± 9 y) and a normal-weight (NW) group (n = 26; BMI 24 ± 3.1 kg/m2; mean age 32 ± 12.3 y). Ten of the OW group (BMI 32.2 ± 4 kg/m2; 46 ± 8 y) then underwent 6-weeks of VLCD (600-800 kcal/day). Fasting plasma BCAA (gas chromatography-mass spectrometry), insulin sensitivity (HOMA-IR) and body-composition (DXA) were assessed before and after VLCD. Total BCAA were higher in OW individuals (sum leucine/isoleucine/valine: 457 ± 85 µM) compared to NW control individuals (365 ± 78 µM, p < 0.001). Despite significant weight loss (baseline 103.9 ± 12.3 to 93 ± 9.6 kg and BMI 32.2 ± 4 to 28.9 ± 3.6 kg/m2), no changes were observed in BCAAs after 6-weeks of VLCD. Moreover, although VLCD resulted in a significant reduction in HOMA-IR (baseline 1.19 ± 0.62 to 0.51 ± 0.21 post-VLCD; p < 0.001), Pearson's r revealed no relationships between BCAA and HOMA-IR, either before (leucine R2: 2.49e-005, p = 0.98; isoleucine R2: 1.211-e006, p = 0.9; valine R2: 0.004, p = 0.85) or after VLCD (leucine R2: 0.003, p = 0.86; isoleucine R2: 0.006, p = 0.82; valine R2: 0.002, p = 0.65). Plasma BCAA are higher in OW compared to NW individuals. However, while 6-weeks VLCD reduced body weight and IR in OW individuals, this was not associated with reductions in BCAA. This suggests that studies demonstrating links between BCAA and insulin resistance in OW individuals, are complex and are not normalised by simply losing weight.


Subject(s)
Amino Acids, Branched-Chain , Insulin Resistance , Male , Humans , Adult , Middle Aged , Young Adult , Amino Acids, Branched-Chain/metabolism , Caloric Restriction , Glycemic Control , Leucine , Isoleucine , Keto Acids , Blood Glucose/metabolism , Obesity , Weight Loss , Overweight/therapy , Valine
15.
Anim Microbiome ; 3(1): 2, 2021 Jan 04.
Article in English | MEDLINE | ID: mdl-33499989

ABSTRACT

BACKGROUND: With a growing demand for safe and sustainable alternatives to antimicrobials, functional feed ingredients such as plant essential oils have been evaluated for their potential to improve gut health. Amongst these, oregano essential oil (OEO) with the main active compounds carvacrol and thymol has been reported to have antimicrobial and antioxidative properties resulting in improved intestinal barrier function and growth in pigs and poultry. However, its impact on the gut microbiota still remains unclear. The aim of this study was to examine the effect of an oregano essential oil phytobiotic on sow and piglet performance and faecal microbiota. RESULTS: Piglets from OEO supplemented sows were significantly heavier at one week of age and showed a trend for improved average daily weight gain from birth to weaning. Post-weaning, maternally supplemented piglets were numerically heavier at 10 weeks post-weaning and at slaughter with a reduced variability in bodyweight. Health records showed that piglets in the OEO supplemented litters had significantly reduced incidence of therapeutic treatment and reduced mortality. In both sows and piglets, the structure and composition of the faecal microbiota varied considerably over time. Sows supplemented with OEO during lactation showed an increase in the relative abundance of Lactobacillaceae family. In addition, there was an increase in the relative abundance of families known to be important in fibre digestion (Fibrobacteriaceae and Akkermansiaceae). Analysis of piglet microbiota at two weeks and four weeks of age revealed a relative decrease in Enterobacteriaceae while butyrate producers (Lachnospiraceae family) were increased at both timepoints. CONCLUSION: We hypothesise that the effects observed from this study were exerted through modulation of the gut microbial communities in the sow and her offspring through maternal microbial transfer. Understanding the link between the gut microbiota and dietary factors represents a keystone to improving health and performance for sustainable pig production. Reducing antimicrobial usage can help to reduce the risk of antimicrobial resistance (AMR) which is a global focus for animal production.

16.
Clin Nutr ; 40(6): 4456-4464, 2021 06.
Article in English | MEDLINE | ID: mdl-33487503

ABSTRACT

BACKGROUND & AIMS: Nutritional composition is key for skeletal muscle maintenance into older age. Yet the acute effects of collagen protein blended with other protein sources, in relation to skeletal muscle anabolism, are ill-defined. We investigated human muscle protein synthesis (MPS) responses to a 20 g blend of collagen protein hydrolysate + milk protein (CP+MP, 125 ml) oral nutritional supplement (ONS) vs. 20 g non-blended milk protein source (MP, 200 ml) ONS, in older adults. METHODS: Healthy older men (N = 8, 71±1 y, BMI: 27±1 kg·m-2) underwent a randomized trial of 20 g protein, from either a CP+MP blend (Fresubin®3.2 kcal DRINK), or a kcal-matched (higher in essential amino acids (EAA) ONS of MP alone. Vastus lateralis (VL) MPS and plasma AA were determined using stable isotope-tracer mass spectrometry; anabolic signaling was quantified via immuno-blotting in VL biopsies taken at baseline and 2/4 h after ONS feeding. Plasma insulin was measured via enzyme-linked immunosorbent assay (ELISA). Measures were taken at rest, after the feed (FED) and after the feed + exercise (FED-EX) conditions (unilateral leg exercise, 6 × 8, 75% 1-RM). RESULTS: MP resulted in a greater increase in plasma leucine (MP mean: 152 ± 6 µM, CP+MP mean: 113 ± 4 µM (Feed P < 0.001) and EAA (MP mean: 917 ± 25 µM, CP+MP mean: 786 ± 15 µM (Feed P < 0.01) than CP+MP. CP + MP increased plasma glycine (peak 385 ± 57 µM (P < 0.05)), proline (peak 323 ± 29 µM (P < 0.01)) and non-essential amino acids (NEAA) (peak 1621 ± 107 µM (P < 0.01)) with MP showing no increase. Plasma insulin increased in both trials (CP+MP: 58 ± 10 mU/mL (P < 0.01), MP: 42 ± 6 mU/mL (P < 0.01), with peak insulin greater with CP+MP vs. MP (P < 0.01). MPS demonstrated equivalent increases in response to CP+MP and MP under both FED (MP: 0.039 ± 0.005%/h to 0.081 ± 0.014%/h (P < 0.05), CP+MP: 0.042 ± 0.004%/h to 0.085 ± 0.007%/h (P < 0.05)) and FED-EX (MP: 0.039 ± 0.005%/h to 0.093 ± 0.013%/h (P < 0.01), CP+MP: 0.042 ± 0.004%/h to 0.105 ± 0.015%/h, (P < 0.01)) conditions. FED muscle p-mTOR fold-change from baseline increased to a greater extent with CP+MP vs. MP (P < 0.05), whilst FED-EX muscle p-eEF2 fold-change from baseline decreased to a greater extent with CP+MP vs. MP (P < 0.05); otherwise anabolic signaling responses were indistinguishable. CONCLUSION: Fresubin®3.2 kcal DRINK, which contains a 20 g mixed blend of CP+MP, resulted in equivalent MPS responses to MP alone. Fresubin® 3.2 Kcal DRINK may provide a suitable alternative to MP for use in older adults and a convenient way to supplement calories and protein to improve patient adherence and mitigate muscle mass loss.


Subject(s)
Amino Acids, Essential/analysis , Collagen , Dietary Supplements , Food, Formulated , Milk Proteins , Muscle Proteins/biosynthesis , Protein Hydrolysates , Aged , Amino Acids/blood , Cross-Over Studies , Food, Formulated/analysis , Humans , Insulin/blood , Male , Milk Proteins/analysis , Muscle, Skeletal/metabolism , Signal Transduction
17.
Clin Nutr ESPEN ; 46: 394-404, 2021 12.
Article in English | MEDLINE | ID: mdl-34857226

ABSTRACT

BACKGROUND & AIMS: The skeletal muscle anabolic effects of n-3 polyunsaturated fatty acids (n-3 PUFA) appear favoured towards women; a property that could be exploited in older women who typically exhibit poor muscle growth responses to resistance exercise training (RET). Here we sought to generate novel insights into the efficacy and mechanisms of n-3 PUFA alongside short-term RET in older women. METHODS: We recruited 16 healthy older women (Placebo n = 8 (PLA): 67±1y, n-3 PUFA n = 8: 64±1y) to a randomised double-blind placebo-controlled trial (n-3 PUFA; 3680 mg/day versus PLA) of 6 weeks fully-supervised progressive unilateral RET (i.e. 6 × 8 reps, 75% 1-RM, 3/wk-1). Strength was assessed by knee extensor 1-RM and isokinetic dynamometry âˆ¼ every 10 d. Thigh fat free mass (TFFM) was measured by DXA at 0/3/6 weeks. Bilateral vastus lateralis (VL) biopsies at 0/2/4/6 weeks with deuterium oxide (D2O) dosing were used to determine MPS responses for 0-2 and 4-6 weeks. Further, fibre cross sectional area (CSA), myonuclei number and satellite cell (SC) number were assessed, alongside muscle anabolic/catabolic signalling via immunoblotting. RESULTS: RET increased 1-RM equally in the trained leg of both groups (+23 ± 5% n-3 PUFA vs. +25 ± 5% PLA (both P < 0.01)) with no significant increase in maximum voluntary contraction (MVC) (+10 ± 6% n-3 PUFA vs. +13 ± 5% PLA). Only the n-3 PUFA group increased TFFM (3774 ± 158 g to 3961 ± 151 g n-3 PUFA (P < 0.05) vs. 3406 ± 201 g to 3561 ± 170 PLA) and type II fibre CSA (3097 ± 339 µm2 to 4329 ± 264 µm2 n-3 PUFA (P < 0.05) vs. 2520 ± 316 µm2 to 3467 ± 303 µm2 in PL) with RET. Myonuclei number increased equally in n-3 PUFA and PLA in both type I and type II fibres, with no change in SC number. N-3 PUFA had no added benefit on muscle protein synthesis (MPS), however, during weeks 4-6 of RET, absolute synthesis rates (ASR) displayed a trend to increase with n-3 PUFA only (5.6 ± 0.3 g d-1 to 7.1 ± 0.5 g d-1 n-3 PUFA (P = 0.09) vs. 5.5 ± 0.5 g d-1 to 6.5 ± 0.5 g d-1 PLA). Further, the n-3 PUFA group displayed greater 4EBP1 activation after acute RE at 6 weeks. CONCLUSION: n3-PUFA enhanced RET gains in muscle mass through type II fibre hypertrophy, with data suggesting a role for MPS rather than via SC recruitment. As such, the present study adds to a literature base illustrating the apparent enhancement of muscle hypertrophy with RET in older women fed adjuvant n3-PUFA.


Subject(s)
Resistance Training , Aged , Dietary Supplements , Exercise , Female , Humans , Middle Aged , Muscle Proteins , Muscle, Skeletal
18.
Biometrics ; 66(1): 249-56, 2010 Mar.
Article in English | MEDLINE | ID: mdl-19397580

ABSTRACT

In this article, we describe a Bayesian approach to the calibration of a stochastic computer model of chemical kinetics. As with many applications in the biological sciences, the data available to calibrate the model come from different sources. Furthermore, these data appear to provide somewhat conflicting information about the model parameters. We describe a modeling framework that allows us to synthesize this conflicting information and arrive at a consensus inference. In particular, we show how random effects can be incorporated into the model to account for between-individual heterogeneity that may be the source of the apparent conflict.


Subject(s)
Biopolymers/chemistry , Databases, Factual , Models, Chemical , Models, Statistical , Bayes Theorem , Calibration , Computer Simulation , Kinetics , Stochastic Processes
19.
Ann R Coll Surg Engl ; 102(7): 488-492, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32326736

ABSTRACT

INTRODUCTION: Management of blunt splenic injury has changed drastically with non-operative management increasingly used in paediatric and adult patients. Studies from America and Australia demonstrate disparities in care of patients treated at paediatric and adult centres. This study assessed management of splenic injuries in UK adolescents. MATERIALS AND METHODS: Data were acquired from the Trauma Audit and Research Network on isolated blunt splenic injuries reported 2006-2015. Adolescents were divided into age groups of 11-15 years and 16-20 years, and injuries classified as minor (grades 1/2) or major (3+). Primary outcomes were needed for splenectomy and blood transfusion. RESULTS: A total of 445 adolescents suffered isolated blunt splenic injuries. Road traffic collisions were the most common mechanism. There were no deaths as a result of isolated blunt splenic injuries, but 49 (11%) adolescents needed transfusions and 105 (23.6%) underwent splenectomies. There was no significant difference observed in the management of adolescents with minor trauma. In major trauma, 11-15-year-olds were more likely to have splenectomies when managed at local trauma units compared with major trauma centres (31% vs 4%, odds ratio 11.5; 95% confidence interval 3.82-34.38, p < 0.0001). Within major trauma centres, older adolescents were more likely to have splenectomies than younger adolescents (35.5% vs 3.8%, odds ratio 14; 95% confidence interval 4.55-43.26, p < 0.0001). There were no significant differences in haemodynamic status, transfusion requirement or embolisation rates. CONCLUSIONS: There appears to be a large variation in the management of isolated blunt splenic injuries in the UK. The reasons for this remain unclear however non-operative management is safe and should be first line management in the haemodynamically stable adolescent, even with major splenic injuries.


Subject(s)
Abdominal Injuries/therapy , Disease Management , Spleen/injuries , Wounds, Nonpenetrating/therapy , Abdominal Injuries/diagnosis , Adolescent , Child , England , Female , Humans , Injury Severity Score , Male , Retrospective Studies , Spleen/diagnostic imaging , Trauma Centers , Trauma Severity Indices , Wales , Wounds, Nonpenetrating/diagnosis , Young Adult
20.
Genetics ; 180(4): 2251-66, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18845848

ABSTRACT

In Saccharomyces cerevisiae, Cdc13 binds telomeric DNA to recruit telomerase and to "cap" chromosome ends. In temperature-sensitive cdc13-1 mutants telomeric DNA is degraded and cell-cycle progression is inhibited. To identify novel proteins and pathways that cap telomeres, or that respond to uncapped telomeres, we combined cdc13-1 with the yeast gene deletion collection and used high-throughput spot-test assays to measure growth. We identified 369 gene deletions, in eight different phenotypic classes, that reproducibly demonstrated subtle genetic interactions with the cdc13-1 mutation. As expected, we identified DNA damage checkpoint, nonsense-mediated decay and telomerase components in our screen. However, we also identified genes affecting casein kinase II activity, cell polarity, mRNA degradation, mitochondrial function, phosphate transport, iron transport, protein degradation, and other functions. We also identified a number of genes of previously unknown function that we term RTC, for restriction of telomere capping, or MTC, for maintenance of telomere capping. It seems likely that many of the newly identified pathways/processes that affect growth of budding yeast cdc13-1 mutants will play evolutionarily conserved roles at telomeres. The high-throughput spot-testing approach that we describe is generally applicable and could aid in understanding other aspects of eukaryotic cell biology.


Subject(s)
Genome, Fungal , Mutation , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae/genetics , Telomere-Binding Proteins/genetics , Telomere/metabolism , DNA Repair , DNA, Fungal , Gene Deletion , Genes, Suppressor , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Telomere-Binding Proteins/metabolism
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