A systematic review of the impact of postoperative aerobic exercise training in patients undergoing surgery for intra-abdominal cancers.

INTRODUCTION: Enhanced recovery after surgery (ERAS) programmes which advocate early mobility after surgery have improved immediate clinical outcomes for patients undergoing abdominal cancer resections with curative intent. However, the impact of continued physical activity on patient-related outcomes and functional recovery is not well defined. The aim of this review was to assess the impact of postoperative aerobic exercise training, either alone or in conjunction with another exercise modality, on patients who have had surgery for intra-abdominal cancer. METHODS: A literature search was performed of electronic journal databases. Eligible papers needed to report an outcome of aerobic capacity in patients older than 18 years of age, who underwent cancer surgery with curative intent and participated in an exercise programme (not solely ERAS) that included an aerobic exercise component starting at any point in the postoperative pathway up to 12 weeks. RESULTS: Eleven studies were deemed eligible for inclusion consisting of two inpatient, one mixed inpatient/outpatient and eight outpatient studies. Meta-analysis of four outpatient studies, each reporting change in 6-min walk test (6MWT), showed a significant improvement in 6MWT with exercise (MD 74.92 m, 95% CI 48.52-101.31 m). The impact on health-related quality of life was variable across studies. CONCLUSION: Postoperative exercise confers benefits in improving aerobic function post surgery and can be safely delivered in various formats (home-based or group/supervised).

Loss of muscle mass in the immediate post-operative period is associated with inadequate dietary protein and energy intake.

Despite the implementation of 'Enhanced Recovery After Surgery' (ERAS) protocols, major abdominal surgery is still associated with significant and detrimental losses of muscle mass and function in the post-operative period. Although ERAS protocols advocate both early mobility and dietary intake, dietary composition in the immediate post-operative period is poorly characterised, despite muscle losses being greatest in this period. Herein, we show in 15 patients (66 ± 6 y, 12:3 M:F) who lost ~10% m. vastus lateralis muscle mass in the 5 days after open colorectal resective surgery, mean energy intake was only ~25% of the minimum ESPEN recommendation of 25 kcal/kg/d and daily dietary protein intake was only ~12% of the ESPEN recommended guidelines of 1.5 g/kg/d. Given the known importance of nutrition for muscle mass maintenance, innovative dietary interventions are needed in the immediate post-operative period, accounting for specific patient dietary preference to maximise compliance (e.g., soft-textured foods).

Caloric restriction improves glycaemic control without reducing plasma branched-chain amino acids or keto-acids in obese men.

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.

Permissive parenting mediates parental stress and child emotions in families of children with Down syndrome.

BACKGROUND: Parenting styles mediate parental stress and child emotions in families of typically developing (TD) children. Our main aim was to study these relations in families of children with Down syndrome (DS), who in past research reported increased parental stress and permissive parenting. METHOD: Our sample included 100 parents of children with DS and 72 parents of TD children age 4-12 years. Parents completed online surveys of parental adjustment and emotion regulation (ER), parenting styles, and child ER and mood. RESULTS: Parents of children with DS reported more distress and permissive parenting than parents of TD children. Within parents of children with DS, there was an indirect effect of parental stress on child emotions through permissive parenting. This effect was partly conditional upon parental ER and positive adjustment. CONCLUSIONS: Results have implications for distressed parents of children with DS whose families may benefit from improved coping strategies and increased support.

Gastrocnemius muscle architecture in distance runners with and without Achilles tendinopathy.

Background: Achilles tendinopathy is a common condition amongst distance runners due to the cumulative repetitive overload of the tendon. Gastrocnemius weakness and inflexibility can predispose to this condition. These predisposing functional deficits could have architectural underpinnings, but the gastrocnemius architecture of distance runners with Achilles tendinopathy has not been previously described or compared to the architecture of healthy distance runners. Objectives: We aimed to investigate the differences in gastrocnemius architecture between distance runners with Achilles tendinopathy and uninjured counterparts. Methods: Twenty distance runners (10 with Achilles tendinopathy; 10 uninjured) were recruited to this study. Ultrasound measurement of the gastrocnemius muscle architecture (pennation angle; fascicle length; muscle thickness; muscle belly length; muscle volume; physiological cross-sectional area) was performed. Results: Gastrocnemius Medial Head (GM) fascicle length was significantly greater (p = 0.02), whilst the physiological cross-sectional area (PCSA) was significantly less (p = 0.01) in the case group. Gastrocnemius Lateral Head (GL) pennation angle (p = 0.01) and PCSA (p = 0.01) were significantly lower, whilst fascicle length was significantly greater (p = 0.01) in the case group. There were no significant between-group differences in GM and GL muscle thickness, muscle belly length, or muscle volume. Conclusion: Components of gastrocnemius architecture differ significantly between distance runners with Achilles tendinopathy and uninjured controls in our study sample. This study cannot infer whether these results are secondary or predisposing to the condition. Further longitudinal investigation is required to explore these relationships further.

Omega-3 supplementation during unilateral resistance exercise training in older women: A within subject and double-blind placebo-controlled trial.

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.

Current perspectives on defining and mitigating frailty in relation to critical illness.

Up to half of ICU survivors, many of whom were premorbidly well, will have residual functional and/or cognitive impairment and be vulnerable to future health problems. Frailty describes vulnerability to poor resolution of homeostasis after a stressor event but it is not clear whether the vulnerability seen after ICU correlates with clinical measures of frailty. In clinical practice, the scales most commonly used in critically ill patients are based on the assessment of severity and survival. Identification and monitoring of frailty in the ICU may be an alternative or complimentary approach, particularly if it helps explain vulnerability during the recovery and rehabilitation period. The purpose of this review is to discuss the use of tools to assess frailty status in the critically ill, and consider their importance in clinical practice. Amongst these, we consider biomarkers with potential to identify patients at greater or lesser risk of developing post-ICU vulnerability.

A collagen hydrolysate/milk protein-blend stimulates muscle anabolism equivalently to an isoenergetic milk protein-blend containing a greater quantity of essential amino acids in older men.

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.

Impacts of rat hindlimb Fndc5/irisin overexpression on muscle and adipose tissue metabolism.

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.

High-intensity interval training produces a significant improvement in fitness in less than 31 days before surgery for urological cancer: a randomised control trial.

OBJECTIVES: To assess the efficacy of high-intensity interval training (HIIT) for improving cardiorespiratory fitness (CRF) in patients awaiting resection for urological malignancy within four weeks. SUBJECTS/PATIENTS AND METHODS: A randomised control trial of consecutive patients aged (>65 years) scheduled for major urological surgery in a large secondary referral centre in a UK hospital. The primary outcome is change in anaerobic threshold (VO2AT) following HIIT vs. standard care. RESULTS: Forty patients were recruited (mean age 72 years, male (39): female (1)) with 34 completing the protocol. Intention to treat analysis showed significant improvements in anaerobic threshold (VO2AT; mean difference (MD) 2.26 ml/kg/min (95% CI 1.25-3.26)) following HIIT. Blood pressure (BP) also significantly reduced in following: HIIT (SBP: -8.2 mmHg (95% CI -16.09 to -0.29) and DBP: -6.47 mmHg (95% CI -12.56 to -0.38)). No reportable adverse safety events occurred during HIIT and all participants achieved >85% predicted maximum heart rate during sessions, with protocol adherence of 84%. CONCLUSIONS: HIIT can improve CRF and cardiovascular health, representing clinically meaningful and achievable pre-operative improvements. Larger randomised trials are required to investigate the efficacy of prehabilitation HIIT upon different cancer types, post-operative complications, socio-economic impact and long-term survival.

Surgical margins for borderline and malignant phyllodes tumours.

BACKGROUND: Phyllodes tumours represent less than 1% of all UK breast neoplasms. Histological features allow classification into benign, borderline or malignant, which has a significant impact on prognosis and recurrence. Currently, there is no consensus for the optimal surgical excision margin. This systematic review aims to provide a comparative summary of outcomes (local recurrence, metastasis and survival) for borderline and malignant phyllodes tumours resected with either ≥1cm or <1cm margins. METHODS: MEDLINE and Embase were systematically searched (1990 to July 2019), in line with PRISMA guidelines. Study quality was assessed using the Newcastle-Ottawa scale. RESULTS: Ten retrospective studies were included (Newcastle-Ottawa scale mean score: 5.6, range: 8-4). Nine reported local recurrence rates, four reported distant metastasis and four reported survival. Meta-analysis pooling demonstrated no statistically significant difference between <1cm and ≥1cm margins in terms of local recurrence rates (relative risk [RR] 1.43, 95% confidence interval [95% CI] 0.70 - 2.93; p=0.33, n=456), distant metastasis (RR 1.93, 95% CI 0.35 - 10.63; p=0.45, n=72) or mortality (RR 1.93, 95% CI 0.42 - 8.77; p=0.40, n=58) for borderline and malignant tumours. Additionally, two studies demonstrated no significant difference in local recurrence for borderline tumours excised with <0.1cm margins compared to ≥1cm. CONCLUSION: Current evidence suggests that margins <1cm may provide adequate tumour excision. This could enable breast conservation in patients with smaller breast-to-tumour volume ratios, with improved cosmetic outcomes and patient satisfaction. A prospective, multi-institutional trial would be appropriate to further elucidate the safety of smaller margins.

The efficacy of 'static' training interventions for improving indices of cardiorespiratory fitness in premenopausal females.

PURPOSE: Cardiovascular disease (CVD) is the leading cause of death worldwide. Many risk factors for CVD can be modified pharmacologically; however, uptake of medications is low, especially in asymptomatic people. Exercise is also effective at reducing CVD risk, but adoption is poor with time-commitment and cost cited as key reasons for this. Repeated remote ischaemic preconditioning (RIPC) and isometric handgrip (IHG) training are both inexpensive, time-efficient interventions which have shown some promise in reducing blood pressure (BP) and improving markers of cardiovascular health and fitness. However, few studies have investigated the effectiveness of these interventions in premenopausal women. METHOD: Thirty healthy females were recruited to twelve supervised sessions of either RIPC or IHG over 4 weeks, or acted as non-intervention controls (CON). BP measurements, flow-mediated dilatation (FMD) and cardiopulmonary exercise tests (CPET) were performed at baseline and after the intervention period. RESULTS: IHG and RIPC were both well-tolerated with 100% adherence to all sessions. A statistically significant reduction in both systolic (- 7.2 mmHg) and diastolic (- 6 mmHg) BP was demonstrated following IHG, with no change following RIPC. No statistically significant improvements were observed in FMD or CPET parameters in any group. CONCLUSIONS: IHG is an inexpensive and well-tolerated intervention which may improve BP; a key risk factor for CVD. Conversely, our single arm RIPC protocol, despite being similarly well-tolerated, did not elicit improvements in any cardiorespiratory parameters in our chosen population.

A double-blind placebo controlled trial into the impacts of HMB supplementation and exercise on free-living muscle protein synthesis, muscle mass and function, in older adults.

Age-related sarcopenia and dynapenia are associated with frailty and metabolic diseases. Resistance exercise training (RET) adjuvant to evidence-based nutritional intervention(s) have been shown as mitigating strategies. Given that ß-hydroxy-ß-methyl-butyrate (HMB) supplementation during RET improves lean body mass in younger humans, and that we have shown that HMB acutely stimulates muscle protein synthesis (MPS) and inhibits breakdown; we hypothesized that chronic supplementation of HMB free acid (HMB-FA) would enhance MPS and muscle mass/function in response to RET in older people. We recruited 16 healthy older men (Placebo (PLA): 68.5 ± 1.0 y, HMB-FA: 67.8 ± 1.15 y) for a randomised double-blind-placebo controlled trial (HMB-FA 3 × 1 g/day vs. PLA) involving a 6-week unilateral progressive RET regime (6 × 8 repetitions, 75% 1-RM, 3 · wk-1). Deuterium oxide (D2O) dosing was performed over the first two weeks (0-2 wk) and last two weeks (4-6 wk) with bilateral vastus lateralis (VL) biopsies at 0-2 and 4-6 wk (each time 75 ± 2 min after a single bout of resistance exercise (RE)) for quantification of early and later MPS responses and post-RE myogenic gene expression. Thigh lean mass (TLM) was measured by DXA, VL thickness and architecture (fibre length and pennation angle) by ultrasound at 0/3/6 wk, and strength by knee extensor 1-RM testing and MVC by isokinetic dynamometry (approx. every 10 days). RET induced strength increases (1-RM) in the exercised leg of both groups (398 ± 22N to 499 ± 30N HMB-FA vs. 396 ± 29N to 510 ± 43N PLA (both P < 0.05)). In addition, maximal voluntary contraction (MVC) also increased (179 ± 12 Nm to 203 ± 12 Nm HMB-FA vs. 185 ± 10 Nm to 217 ± 11 Nm PLA (both P < 0.05); with no group differences. VL muscle thickness increased significantly in the exercised leg in both groups, with no group differences. TLM (by DXA) rose to significance only in the HMB-FA group (by 5.8%-5734 ± 245 g p = 0.015 vs. 3.0% to 5644 ± 323 g P = 0.06 in PLA). MPS remained unchanged in the untrained legs (UT) 0-2 weeks being 1.06 ± 0.08%.d-1 (HMB-FA) and 1.14 ± 0.09%.d-1 (PLA), the trained legs (T) exhibited increased MPS in the HMB-FA group only at 0-2-weeks (1.39 ± 0.10%.d-1, P < 0.05) compared with UT: but was not different at 4-6-weeks: 1.26 ± 0.05%.d-1. However, there were no significant differences in MPS between the HMB-FA and PLA groups at any given time point and no significant treatment interaction observed. We also observed significant inductions of c-Myc gene expression following each acute RE bout, with no group differences. Further, there were no changes in any other muscle atrophy/hypertrophy or myogenic transcription factor genes we measured. RET with adjuvant HMB-FA supplements in free-living healthy older men did not enhance muscle strength or mass greater than that of RET alone (PLA). That said, only HMB-FA increased TLM, supported by early increases in chronic MPS. As such, chronic HMB-FA supplementation may result in long term benefits in older males, however longer and larger studies may be needed to fully determine the potential effects of HMB-FA supplementation; translating to any functional benefit.

Continuous flow hygroscopicity-resolved relaxed eddy accumulation (Hy-Res REA) method of measuring size-resolved sodium chloride particle fluxes.

The accurate representation of aerosols in climate models requires direct ambient measurement of the size- and composition-dependent particle production fluxes. Here, we present the design, testing, and analysis of data collected through the first instrument capable of measuring hygroscopicity-based, size-resolved particle fluxes using a continuous-flow Hygroscopicity-Resolved Relaxed Eddy Accumulation (Hy-Res REA) technique. The Hy-Res REA system used in this study includes a 3D sonic anemometer, two fast-response solenoid valves, two condensation particle counters, a scanning mobility particle sizer, and a hygroscopicity tandem differential mobility analyzer. The different components of the instrument were tested inside the US Environmental Protection Agency's Aerosol Test Facility for sodium chloride and ammonium sulfate particle fluxes. The new REA system design does not require particle accumulation, and therefore avoids the diffusional wall losses associated with long residence times of particles inside the air collectors of traditional REA devices. A linear relationship was found between the sodium chloride particle fluxes measured by eddy covariance and REA techniques. The particle detection limit of the Hy-Res REA flux system is estimated to be ~3 × 105 m-2 s-1. The estimated sodium chloride particle classification limit, for the mixture of sodium chloride and ammonium sulfate particles of comparable concentrations, is ~6 × 106 m-2 s-1.

Trauma to the Superior Mesenteric Artery and Superior Mesenteric Vein: A Narrative Review of Rare but Lethal Injuries.

Mesenteric vessels, including the superior mesenteric artery (SMA) and vein (SMV), provide and drain the rich blood supply of the midgut and hindgut. SMA and SMV injuries are rare and often lethal. Clinical management of these injuries is not well established, but treatment options include operative, non-operative, and endovascular strategies. A narrative review of the literature was conducted using MEDLINE Complete-EBSCO. Relevant studies, specifically those focusing on diagnosis and management of SMA and SMV injuries, were selected. Only original reports and collected series were selected to prevent duplication of cases. A search of the literature for mesenteric arterial injuries yielded 87 studies. Vessel-specific breakdown of the studies yielded 40 with SMA injuries and 41 with SMV injuries. These searches were winnowed to 26 individual studies, which were included in this collective review. Limitations of this study are similar to all narrative literature reviews: the dependence on previously published research and availability of references as outlined in our methodology. Although historically rare, mesenteric vessel injuries are seen with increasing incidence and continue to present a challenge to trauma surgeons due to their daunting mortality rates. Currently, universal treatment guidelines do not exist, but the various options for their management have been extensively reviewed in the literature.

Impact of the calcium form of ß-hydroxy-ß-methylbutyrate upon human skeletal muscle protein metabolism.

BACKGROUND & AIMS: ß-hydroxy-ß-methylbutyrate (HMB) is purported as a key nutritional supplement for the preservation of muscle mass in health, disease and as an ergogenic aid in exercise. Of the two available forms of HMB (calcium (Ca-HMB) salt or free acid (FA-HMB)) - differences in plasma bioavailability have been reported. We previously reported that ∼3 g oral FA-HMB increased muscle protein synthesis (MPS) and reduced muscle protein breakdown (MPB). The objective of the present study was to quantify muscle protein metabolism responses to oral Ca-HMB. METHODS: Eight healthy young males received a primed constant infusion of 1,2 13C2 leucine and 2H5 phenylalanine to assess MPS (by tracer incorporation in myofibrils) and MPB (via arterio-venous (A-V) dilution) at baseline and following provision of ∼3 g of Ca-HMB; muscle anabolic (MPS) and catabolic (MPB) signalling was assessed via immunoblotting. RESULTS: Ca-HMB led a significant and rapid (<60 min) peak in plasma HMB concentrations (483.6 ± 14.2 µM, p < 0.0001). This rise in plasma HMB was accompanied by increases in MPS (PA: 0.046 ± 0.004%/h, CaHMB: 0.072 ± 0.004%/h, p < 0001) and suppressions in MPB (PA: 7.6 ± 1.2 µmol Phe per leg min-1, Ca-HMB: 5.2 ± 0.8 µmol Phe per leg min-1, p < 0.01). Increases in the phosphorylation of mTORc1 substrates i.e. p70S6K1 and RPS6 were also observed, with no changes detected in the MPB targets measured. CONCLUSIONS: These findings support the pro-anabolic properties of HMB via mTORc1, and show that despite proposed differences in bioavailability, Ca-HMB provides a comparable stimulation to MPS and suppression of MPB, to FA-HMB, further supporting its use as a pharmaconutrient in the modulation of muscle mass.

Rabacfosadine for relapsed canine B-cell lymphoma: Efficacy and adverse event profiles of 2 different doses.

Rabacfosadine (RAB), a novel double prodrug of the acyclic nucleotide phosphonate PMEG, preferentially targets neoplastic lymphocytes with reduced off target toxicity. Historical studies have suggested that every 21-day dosing is effective with acceptable toxicity. The purpose of this study was to evaluate RAB's safety and efficacy at 2 different doses every 21 days in dogs with relapsed B-cell lymphoma. Dogs that had failed 1 doxorubicin-based chemotherapy protocol were eligible for inclusion in this prospective trial. Once enrolled, dogs were randomized to receive RAB at either 0.82 mg/kg or 1.0 mg/kg as a 30-minute IV infusion every 21 days for up to 5 treatments. Response assessment and adverse event (AE) evaluation were performed every 21 days via VCOG criteria. Fifty dogs were enrolled, with 16 treated at 0.82 mg/kg and 34 treated at 1.0 mg/kg. The overall response rate was 74%, with 45% of dogs experiencing a complete response (CR). The median progression free intervals (PFIs) were 108 days, 172 days and 203 days for all dogs, all responders, and all CRs, respectively. Response rates and PFIs were similar in both treatment groups. The incidence of AEs, dose delays, dose reductions and withdrawals were not statistically different between the 2 groups. The AEs observed were similar to those previously reported and included hematologic, gastrointestinal, dermatologic and pulmonary AEs. One dog had grade 5 pulmonary fibrosis; otherwise, AEs resolved with supportive treatment. Rabacfosadine is a generally well tolerated, effective chemotherapy option for dogs with relapsed B-cell lymphoma.

Penetrating cardiac injuries: predictive model for outcomes based on 2016 patients from the National Trauma Data Bank.

BACKGROUND: Penetrating cardiac injuries are uncommon and lethal. The objectives of this study are to examine the national profile of cardiac injuries, identify independent predictors of outcome, generate, compare and validate previous predictive models for outcomes. We hypothesized that National Trauma Data Bank (NTDB) given its large number of patients, would validate these models. METHODS: The NTDB was queried for data on cardiac injuries, using survival as the main outcome measure. Statistical analysis was performed utilizing univariate and stepwise logistic regression. The stepwise logistic regression model was then compared with other predictive models of outcome. RESULTS: There were 2016 patients with penetrating cardiac injuries identified from 1,310,720 patients. Incidence: 0.16%. Mechanism of injury: GSWs-1264 (63%), SWs-716 (36%), Shotgun/impalement-19/16 (1%). Mean RTS 1.75, mean ISS 27 ± 23. Overall survival 675 (33%). 830 patients (41%) underwent ED thoracotomy, 47 survived (6%). Survival stratified by mechanism: GSWs 114/1264 (10%), SWs 564/717 (76%). Predictors of outcome for mortality-univariate analysis: vital signs, RTS, ISS, GCS: Field CPR, ED intubation, ED thoracotomy and aortic cross-clamping (p < 0.001). Stepwise logistic regression identified cardiac GSW's (p < 0.001; AOR 26.85; 95% CI 17.21-41.89), field CPR (p = 0.003; AOR 3.65; 95% CI 1.53-8.69), the absence of spontaneous ventilation (p = 0.008; AOR 1.08, 95% CI 1.02-1.14), the presence of an associated abdominal GSW (p = 0.009; AOR 2.58, 95% CI 1.26-5.26) need for ED airway (p = 0.0003 AOR 1386.30; 95% CI 126.0-15251.71) and aortic cross-clamping (p = 0.0003 AOR 0.18; 95% CI 0.11-0.28) as independent predictors for mortality. Overall predictive power of model-93%. CONCLUSION: Predictors of outcome were identified. Overall survival rates are lower than prospective studies report. Predictive model from NTDB generated larger number of strong independent predictors of outcomes, correlated and validated previous predictive models.

Path Analysis of Campus Walkability/Bikeability and College Students' Physical Activity Attitudes, Behaviors, and Body Mass Index.

PURPOSE: The purpose of this study was to assess the relationship between the walkability/bikeability of college campuses and students' body mass index (BMI) with student physical activity (PA) attitudes and behaviors as potential mediators. DESIGN: Cross-sectional. SETTING: Thirteen university campuses. PARTICIPANTS: A total of 1384 student participants. MEASURES: Walkability/bikeability environmental score (ES): 12-item audit assessed an average of 44 path segments per campus. Students were measured for height and weight and completed online surveys. Physical activity stage of change/behavior intentions were assessed using the transtheoretical model. The Cognitive Behavioral Physical Activity Questionnaire assessed outcome expectations, self-regulation, and personal barriers. International Physical Activity Questionnaire assessed walking-, moderate-, and vigorous-intensity PA. ANALYSIS: Descriptive statistics, zero-order correlations, and path analysis with maximum likelihood estimation. RESULTS: The overall model fit was good with χ2 of 171.388 ( df = 18), P < .001, comparative fit index value of .95, and a root mean square of approximation of .079. After controlling for gender, there was a direct negative association between walkability/bikeability ES and BMI (ß = -.085) and positive association between personal barriers and BMI (ß = .134). Walkability/bikeability ES was positively associated with walking-intensity PA (ß = .010). Self-regulation was positively associated with moderate-intensity PA (ß = .213), which, in turn, was negatively associated with BMI (ß = -.057). CONCLUSIONS: The ease of walking and biking on a campus was related to college students' walking behavior and their BMI. Students' PA behavioral intentions were associated with moderate PA and lower BMI. These results provide evidence to focus on policies and structural supports for walkable/bikeable environments to supplement and enhance interventions encouraging individual behavior change for PA and weight management.

The academic-practice gap: Strategies for an enduring problem.

The academic-practice gap in nursing is well documented. Academe is criticized for producing nurses insufficiently prepared to fully participate in patient care. Practice settings are criticized for having unrealistic expectations of new graduates. This article is based on a review of the literature and an exploration of contemporary practices used to bridge academic and practice partnerships. Differences in outcome expectations for new graduates between academe and practice are outlined and consequences of the gap for new graduates, patients, and employers are discussed. Five specific strategies to address the gap are discussed, with the primary realm and responsibility for two falling to education, one to practice, and two to both. Strategies discussed include increased use of simulated learning in nursing education; disruptive innovations in education that promote learner-centered active learning; extended orientation/Transition to Practice Programs for new graduates; dedicated education units; and academic service partnerships. Current literature suggests the viewpoints of academic and practice leaders continue to appear divergent. Closing the gap will require a dedicated and coordinated response from both academe and clinical practice.