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Background: The ageing process is intrinsically associated with decline in physical endurance, muscle strength and gait ability and balance, which all contribute to functional disability. Regular physical training, and more particularly multicomponent training (MCT), has demonstrated many health benefits.Objective: To evaluate the evidence of the health benefits of MCT including endurance training, muscle strengthening, balance exercises, and/or stretching (i.e. flexibility training) and/or coordination training in adults aged 65 years or over.Methods: A comprehensive, systematic database search for manuscripts was performed in CINAHL Plus, Embase, Medline, PubMed Central, ScienceDirect, Scopus, Sport Discus and Web of Science using key words. For potential inclusion, two reviewers independently assessed all intervention studies published in English language from 1 January 2000 to 30 April 2015.Results: Of 2525 articles initially identified, 27 studies were finally included in this systematic review. They were all divided into five categories according to their main outcome measurements (cardio-respiratory fitness, metabolic outcomes, functional and cognitive functions and quality of life, QoL). These studies reported that MCT has a significant beneficial effect on cardio-respiratory fitness and on metabolic outcomes. Substantial improvement in functional and cognitive performance was also measured and a slighter but positive effect on QoL.Conclusion: Overall, this review demonstrates a positive effect of MCT with functional benefits and positive health outcomes for seniors. Based on this evidence, clinicians should encourage all adults aged 65 or over to engage in MCT programmes to favour healthy ageing and keeping older members of our society autonomous and independent. [ABSTRACT FROM AUTHOR]

Background: The prevalence of obesity is rapidly increasing in older patients and it is ubiquitous in many developed countries. Obesity is related to various negative health outcomes, making it a major public health target for intervention.Purpose: The aim of this study was to explore and summarise the literature that addresses endurance training alone or combined with nutrition interventions to combat obesity in obese patients over age 60.Methods: We searched online electronic databases up to September 2014 for original observational and intervention studies published between 1995 and 2014 on the relationship between endurance training alone or combined with a diet in obese patients over 60 regarding health outcomes.Results: Twenty-six studies examined interventions aimed specifically at promoting endurance training alone or combined with diet for older obese patients over 60. These studies demonstrated a positive effect of this intervention on the primary prevention of cardiovascular disease, and a significant beneficial effect on the lipid profile. Improvement of body composition and insulin sensitivity, and a reduction in blood pressure were also well established.Conclusions: Overall, this review demonstrates a positive effect of endurance training alone or combined with diet on health outcomes and metabolic benefits in older adults. Clinicians can now use this evidence to formulate actions to encourage the older obese to profit from the health benefits of endurance training and diet. This will not only help reduce the dramatic increase in the number of older obese but also help prevent sarcopenic obesity, which is a complex challenge for healthcare professionals. [ABSTRACT FROM AUTHOR]

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Background Fluorescence videography is a promising technique for assessing bowel perfusion. Fluorescence-based enhanced reality ( FLER) is a novel concept, in which a dynamic perfusion cartogram, generated by computer analysis, is superimposed on to real-time laparoscopic images. The aim of this experimental study was to assess the accuracy of FLER in detecting differences in perfusion in a small bowel resection-anastomosis model. Methods A small bowel ischaemic segment was created laparoscopically in 13 pigs. Animals were allocated to having anastomoses performed at either low perfusion (25 per cent; n = 7) or high perfusion (75 per cent; n = 6), as determined by FLER analysis. Capillary lactate levels were measured in blood samples obtained by serosal puncturing in the ischaemic area, resection lines and vascularized areas. Pathological inflammation scoring of the anastomosis was carried out. Results Lactate levels in the ischaemic area (mean(s.d.) 5·6(2·8) mmol/l) were higher than those in resection lines at 25 per cent perfusion (3·7(1·7) mmol/l; P = 0·010) and 75 per cent perfusion (2·9(1·3) mmol/l; P < 0·001), and higher than levels in vascular zones (2·5(1·0) mmol/l; P < 0·001). Lactate levels in resection lines with 75 per cent perfusion were lower than those in lines with 25 per cent perfusion ( P < 0·001), and similar to those in vascular zones ( P = 0·188). Levels at resection lines with 25 per cent perfusion were higher than those in vascular zones ( P = 0·001). Mean(s.d.) global inflammation scores were higher in the 25 per cent perfusion group compared with the 75 per cent perfusion group for mucosa/submucosa (2·1(0·4) versus 1·2(0·4); P = 0·003) and serosa (1·8(0·4) versus 0·8(0·8); P = 0·014). A ratio of preanastomotic lactate levels in the ischaemic area relative to the resection lines of 2 or less was predictive of a more severe inflammation score. Conclusion In an experimental model, FLER appeared accurate in discriminating bowel perfusion levels. [ABSTRACT FROM AUTHOR]

Introduction: Microbiopsies are increasingly used as an alternative to the standard Bergström technique for skeletal muscle sampling. The potential impact of these two different procedures on mitochondrial respiration rate is unknown. The objective of this work was to compare microbiopsies versus Bergström procedure on mitochondrial respiration in skeletal muscle.Methods: 52 vastus lateralis muscle samples were obtained from 13 anesthetized pigs, either with a Bergström [6 gauges (G)] needle or with microbiopsy needles (12, 14, 18G). Maximal mitochondrial respiration (V GM-ADP) was assessed using an oxygraphic method on permeabilized fibers.Results: The weight of the muscle samples and V GM-ADP decreased with the increasing gauge of the needles. A positive nonlinear relationship was observed between the weight of the muscle sample and the level of maximal mitochondrial respiration (r = 0.99, p < 0.05) and between needle size and maximal mitochondrial respiration (r = 0.99, p < 0.05).Conclusion: Microbiopsies give lower muscle sample weight and maximal rate of mitochondrial respiration compared to the standard Bergström needle.Therefore, the higher the gauge (i.e. the smaller the size) of the microbiopsy needle, the lower is the maximal rate of respiration. Microbiopsies of skeletal muscle underestimate the maximal mitochondrial respiration rate, and this finding needs to be highlighted for adequate interpretation and comparison with literature data. [ABSTRACT FROM AUTHOR]

Introduction: Microbiopsies are increasingly used as an alternative to the standard Bergström technique for skeletal muscle sampling. The potential impact of these two different procedures on mitochondrial respiration rate is unknown. The objective of this work was to compare microbiopsies versus Bergström procedure on mitochondrial respiration in skeletal muscle. Methods: 52 vastus lateralis muscle samples were obtained from 13 anesthetized pigs, either with a Bergström [6 gauges (G)] needle or with microbiopsy needles (12, 14, 18G). Maximal mitochondrial respiration ( V) was assessed using an oxygraphic method on permeabilized fibers. Results: The weight of the muscle samples and V decreased with the increasing gauge of the needles. A positive nonlinear relationship was observed between the weight of the muscle sample and the level of maximal mitochondrial respiration ( r = 0.99, p < 0.05) and between needle size and maximal mitochondrial respiration ( r = 0.99, p < 0.05). Conclusion: Microbiopsies give lower muscle sample weight and maximal rate of mitochondrial respiration compared to the standard Bergström needle.Therefore, the higher the gauge (i.e. the smaller the size) of the microbiopsy needle, the lower is the maximal rate of respiration. Microbiopsies of skeletal muscle underestimate the maximal mitochondrial respiration rate, and this finding needs to be highlighted for adequate interpretation and comparison with literature data. [ABSTRACT FROM AUTHOR]

The effects of mitochondrial uncoupling on skeletal muscle mitochondrial adaptation and maximal exercise capacity are unknown. In this study, rats were divided into a control group (CTL, n = 8) and a group treated with 2,4-dinitrophenol, a mitochondrial uncoupler, for 28 days (DNP, 30 mg·kg-1·day-1 in drinking water, n = 8). The DNP group had a significantly lower body mass (P < 0.05) and a higher resting oxygen uptake (V02, P < 0.005). The incremental treadmill test showed that maximal running speed and running economy (P < 0.01) were impaired but that maximal V02 (V02max) was higher in the DNP-treated rats (P < 0.05). In skinned gastrocnemius fibers, basal respiration (V0) was higher (P < 0.01) in the DNP-treated animals, whereas the acceptor control ratio (ACR, Vmax/V0) was significantly lower (P < 0.05), indicating a reduction in OXPHOS efficiency. In skeletal muscle, DNP activated the mitochondrial biogenesis pathway, as indicated by changes in the mRNA expression of PGC1-α and -β, NRF-1 and -2, and TFAM, and increased the mRNA expression of cytochrome oxidase 1 (P < 0.01). The expression of two mitochondrial proteins (prohibitin and Ndufs 3) was higher after DNP treatment. Mitochondrial fission 1 protein (Fis-1) was increased in the DNP group (P < 0.01), but mitofusin-1 and -2 were unchanged. Histochemical staining for NADH dehydrogenase and succinate de-hydrogenase activity in the gastrocnemius muscle revealed an increase in the proportion of oxidative fibers after DNP treatment. Our study shows that mitochondrial uncoupling induces several skeletal muscle adaptations, highlighting the role of mitochondrial coupling as a critical factor for maximal exercise capacities. These results emphasize the importance of investigating the qualitative aspects of mitochondrial function in addition to the amount of mitochondria. [ABSTRACT FROM AUTHOR]

Remote organ impairments are frequent and increase patient morbidity and mortality after lower limb ischemia-reperfusion (IR). We challenged the hypothesis that lower limb IR might also impair lung, renal, and liver mitochondrial respiration. Two-hour tourniquet-induced ischemia was performed on both hindlimbs, followed by a two-hour reperfusion period in C57BL6 mice. Lungs, liver and kidneysmaximal mitochondrial respiration (Vmax), complexes II, III, and IVactivity (Vsucc), and complex IV activity (VTMPD) were analyzed on isolated mitochondria. Lower limb IR decreased significantly lung Vmax (29.4 ± 3.3 versus 24 ± 3.7 μmol O2/min/g dry weight, resp.; P = 0.042) and tended to reduce Vsucc and VTMPD. IR did not modify liver but increased kidneys mitochondrial respiration (79.5± 19.9 versus 108.6± 21.4, P = 0.035, and 126± 13.4 versus 142.4± 10.4 μmol O2/min/g dry weight for Vmax and Vsucc, resp.). Kidneys mitochondrial coupling was increased after IR (6.5 ± 1.3 versus 8.8 ± 1.1, P = 0.008).There were no histological changes in liver and kidneys. Thus, lung mitochondrial dysfunction appears as a new early marker of hindlimb IR injuries in mice. Further studies will be useful to determine whether enhanced kidneys mitochondrial function allows postponing kidney impairment in lower limb IR setting. [ABSTRACT FROM AUTHOR]

Exercise is an efficient strategy for myocardial protection against ischemia–reperfusion (IR) injury. Although endothelial nitric oxide synthase (eNOS) is phosphorylated and activated during exercise, its role in exercise-induced cardioprotection remains unknown. This study investigated whether modulation of eNOS activation during IR could participate in the exercise-induced cardioprotection against IR injury. Hearts isolated from sedentary or exercised rats (5 weeks training) were perfused with a Langendorff apparatus and IR performed in the presence or absence of NOS inhibitors [ N-nitro- l-arginine methyl ester, l-NAME or N5-(1-iminoethyl)- l-ornithine, l-NIO] or tetrahydrobiopterin (BH 4). Exercise training protected hearts against IR injury and this effect was abolished by l-NAME or by l-NIO treatment, indicating that exercise-induced cardioprotection is eNOS dependent. However, a strong reduction of eNOS phosphorylation at Ser1177 (eNOS-P Ser1177) and of eNOS coupling during early reperfusion was observed in hearts from exercised rats (which showed higher eNOS-P Ser1177 and eNOS dimerization at baseline) in comparison to sedentary rats. Despite eNOS uncoupling, exercised hearts had more S-nitrosylated proteins after early reperfusion and also less nitro-oxidative stress, indexed by lower malondialdehyde content and protein nitrotyrosination compared to sedentary hearts. Moreover, in exercised hearts, stabilization of eNOS dimers by BH 4 treatment increased nitro-oxidative stress and then abolished the exercise-induced cardioprotection, indicating that eNOS uncoupling during IR is required for exercise-induced myocardial cardioprotection. Based on these results, we hypothesize that in the hearts of exercised animals, eNOS uncoupling associated with the improved myocardial antioxidant capacity prevents excessive NO synthesis and limits the reaction between NO and O 2·− to form peroxynitrite (ONOO −), which is cytotoxic. [ABSTRACT FROM AUTHOR]

Copyright of Les Cahiers de l'Année Gérontologique is the property of Lavoisier and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Les Cahiers de l'Année Gérontologique is the property of Lavoisier and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Les Cahiers de l'Année Gérontologique is the property of Lavoisier and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Les Cahiers de l'Année Gérontologique is the property of Lavoisier and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Protects against reperfusion injury [ABSTRACT FROM AUTHOR]

The aims of this study were to evaluate the feasibility of successive diffusing capacity of the lung for carbon monoxide (DLCO) measurements during two different exercise tests (upright cycling), and to compare the relationships between DLCO and pulmonary blood flow (Qc). Eight healthy subjects performed an incremental test (1-min step) and a strenuous 30-min intermittent-work exercise test (4 min at low and 2 min at high workload). Intrabreath DLCO and Qc were calculated by assessing the uptake of CO and C2H2 during exhalation. DLCO could be measured reliably up to 73–90% of peak oxygen consumption (VO2) during the incremental test, and up to 85–95% of peak VO2 during the intermittent test. The coefficients of variation of DLCO and Qc measured during two successive constant-load exercise tests were 5–6% and 7–11%, respectively. The highest values of DLCO, Qc and VO2 measured during the incremental and intermittent tests were similar (56 and 51 mL/mmHg/min for DLCO, 18.7 and 18.3 L/min, for Qc and 2.4 and 2.3 L/min for VO2, respectively). The main observed result was that the linear relationships between DLCO and Qc were similar whatever the exercise type. This allows DLCO comparisons, with regards to Qc, during different exercise protocols. [ABSTRACT FROM AUTHOR]

Background: Increased brain natriuretic peptide (BNP) in cardiovascular disease is thought to be a compensatory protective mechanism allowing to delay the occurrence of terminal heart failure. Heart transplantation should normalize the neuroendocrine balance but BNP remains elevated in stable heart-transplant recipients (Htx). Such increase has been related to persistent endothelial and cardiac dysfunctions. The purpose of this study was to determine whether selected Htx, presenting with normal hemodynamic and cardiac systolic and diastolic functions on both side of the heart, show a normalization of their BNP plasma values. Methods: Of a cohort of well-being 26 Htx, we selected 12 patients with normal hemodynamics and left and right heart systolic and diastolic functions and compared their circulating BNP, cyclic guanosine monophosphate (cGMP) (the BNP second messenger) and endothelin-1 (ET) values with that of 12 age-, body mass index- and mean arterial pressure-matched controls. Cardiac function determination by echodoppler included cardiac filling pressures assessment using tissue Doppler imaging. Blood samples for biological and hormonal determinations were drawn at rest, within 15 min before echocardiography. Results: As selected, hemodynamic and left and right heart systolic and diastolic functions were located in the normal range in Htx. Plasma ET value was also similar in Htx and controls (20.7 ± 0.9 vs. 19.6 ± 0.9 fmol/mL). However, circulating BNP, like cGMP, was still significantly increased after heart transplantation, when compared with controls (33.8 ± 8.5 vs. 4.0 ± 0.9 pg/mL, p = 0.002 and 8.2 ± 1.1 vs. 4.4 ± 0.3 nmol/L, p = 0.003) for BNP and cGMP, respectively, in Htx and controls. Interestingly, the sole correlation observed was between BNP and cGMP (r = 0.85, p < 0.0001) after heart transplantation. Conclusions: After heart transplantation, BNP remained increased despite the normalization of hemodynamic and cardiac systolic and diastolic functions. This suggests that such endocrine heart stimulation should not be viewed only as a hemodynamic marker in Htx. Further studies will be useful to investigate the role of pro-inflammatory cytokines and whether elevated BNP still possesses antifibrotic properties, further supporting the interest of enhancing its activity after heart transplantation. [ABSTRACT FROM AUTHOR]

The purpose of the study was to determine the potential beneficial effect of six weeks oral L-arginine supplementation (LAS) on endurance exercise, an important determinant of daily-life activity in patients with chronic stable heart failure (CHF). After an initial incremental maximal exercise test, CHF patients performed an identical thirty-minute interval endurance exercise test before and after six weeks with (L-arginine group; ARC) or without LAS (control group; CTL). Hemodynamic, respiratory, and metabolic parameters were determined at rest, during exercise, and during recovery. Mean heart rate decreased throughout exercise and recovery after LAS (-8.2±1.4 b·min-1 p=0.003 and - 6.7 ± 1.6 b·min-1 p <0.001, respectively), systemic blood pressure and respiratory parameters remaining unchanged. Resting L-argininaemia increased from 102±11 to 181 ±37 µmol·l-1 (p <0.004) and exercise-induced peak increase in plasma lactate was blunted after LAS (4.13±0.75 vs. 3.13±0.39 mmol·l-1; p=0.02). No significant change was observed in the control group. In heart failure patients, six weeks oral LAS enhances endurance exercise tolerance, reducing both heart rate and circulating lactates. This suggests that chronic LAS might be useful as a therapeutic adjuvant in order to improve the patient's physical fitness. [ABSTRACT FROM AUTHOR]

STUDY OBJECTIVES: The monitoring of cardiac output (CO) during exercise rehabilitation in patients with COPD, often including strenuous exercise, is advisable. Invasive methods (thermodilution, Fick method) are accurate, but for clinical routine use noninvasive CO estimation is required. We have shown that impedance cardiography (Physio Flow; Manatec Biomedical; Macheren, France) is reliable in COPD patients at rest and during a recumbent, light-intensity exercise. The aim of our study was to evaluate the validity of this noninvasive device in COPD patients during a maximal incremental exercise test (IET) and also during a strenuous intermittent work exercise test (IWET). DESIGN: Prospective comparative study of the impedance cardiograph vs the direct Fick method applied to oxygen. PATIENTS: Eight patients with moderate-to-severe COPD (59 +/- 6 years old; FEV(1), 38 +/- 15% predicted; residual volume, 194 +/- 64% predicted) [mean +/- SD].Measurements and main results: Forty-nine simultaneous measurements of CO by means of the direct Fick method (COfick) and CO measured by the impedance cardiograph (COpf) were obtained during the IET, and 108 measurements were made during the IWET. The correlation coefficients between the two measurements were r = 0.85 and r = 0.71 for the IET and the IWET, respectively. COpf was higher than COfick. The difference between the two methods was 3.2 +/- 2.9 L/min during the IET and 2.5 +/- 2.1 L/min during the IWET. Expressed as a percentage of the mean of the two measurements, this corresponded to 31 +/- 21% and 25 +/- 20%, respectively. CONCLUSIONS: The relatively high number of values differing by > 20% precludes the use of impedance cardiography in clinical routine in such a difficult setting (hyperinflated patients and intense exercise). [ABSTRACT FROM AUTHOR]

Abstract The atrial natriuretic peptide (ANP) plays an important role in chronic heart failure (CHF), delaying the progression of the disease. However, despite high ANP levels, natriuresis falls when CHF progresses from a compensated to a decompensated state, suggesting emergence of renal resistance to ANP. Several mechanisms have been proposed to explain renal hyporesponsiveness, including decreased renal ANP availability, down-regulation of natriuretic peptide receptors and altered ANP intracellular transduction signal. It has been demonstrated that the activity of neutral endopeptidase (NEP) is increased in CHF, and that its inhibition enhances renal cGMP production and renal sodium excretion. In vitro as well as in vivo studies have provided strong evidence of an increased degradation of intracellular cGMP by phosphodiesterase in CHF. In experimental models, ANP-dependent natriuresis is improved by phosphodiesterase inhibitors, which may arise as new therapeutic agents in CHF. Sodium-retaining systems likely contribute to renal hyporesponsiveness to ANP through different mechanisms. Among these systems, the renin-angiotensin-aldosterone system has received particular attention, as angiotensin II and ANP have renal actions at the same sites and inhibition of angiotensin-converting enzyme and angiotensin-receptor blockade improve ANP hyporesponsiveness. Less is known about the interactions between the sympathetic nervous system, endothelin or vasopressin and ANP, which may also blunt ANP-induced natriuresis. To summarize, renal hyporesponsiveness to ANP is probably multifactorial. New treatments designed to restore renal ANP efficiency should limit sodium retention in CHF patients and thus delay the progression to overt heart failure. [ABSTRACT FROM AUTHOR]

We previously described a strong concordance between nocturnal oscillations in plasma renin activity (PRA) and the rapid eye movement (REM) and non-REM (NREM) sleep cycles, but the mechanisms inducing PRA oscillations remain to be identified. This study was designed to examine whether they are linked to sleep stage-related changes in arterial blood pressure (ABP). Analysis of sleep electroencephalographic (EEG) activity in the delta frequency band, intra-arterial pressure, and PRA measured every 10 min was performed in eight healthy subjects. Simultaneously, the ratio of low frequency power to low frequency power + high frequency power [LF/(LF + HF)] was calculated using spectral analysis of R–R intervals. The cascade of physiological events that led to increased renin release during NREM sleep could be characterized. First, the LF/(LF + HF) ratio significantly (P < 10-4 ) decreased, indicating a reduction in sympathetic tone, concomitantly to a significant (P < 10-3 ) decrease in mean arterial pressure (MAP). Delta wave activity increased (P < 10-4 ) 10–20 min later and was associated with a lag of 0–10 min with a significant rise in PRA (P < 10-4 ). Rapid eye movement sleep was characterized by a significant increase (P < 10-4 ) in the LF/(LF + HF) ratio and a decrease (P < 10-4 ) in delta wave activity and PRA, whereas MAP levels were highly variable. Overnight cross-correlation analysis revealed that MAP was inversely correlated with delta wave activity and with PRA (P < 0.01 in all subjects but one). These results suggest that pressure-dependent mechanisms elicit the nocturnal PRA oscillations rather than common central processes controlling both the generation of slow waves and the release of renin from the kidney. [ABSTRACT FROM AUTHOR]

Activation of phospholipase D (PLD) occurs in response to various stimuli and results from the activity of two isozymes, hPLD1 and hPLD2. PLD activity appears to be involved in several myeloid cell processes during their development and activation, including proliferation of myeloblasts in the bone marrow and secretion, phagocytosis and NADPH oxidase activation, essential functions of differentiated neutrophils. The present work studies PLD characteristics, activity and both iso-zyme expression during maturation and differentiation of myeloid cells by using three different systems: leukemic mye-loblasts at different stages of maturation, terminally differentiated neutrophils ex vivo and four human myeloid cell lines, NB4, HL-60, PLB 985 and U937, induced to differentiate with all-trans retinoic acid (ATRA), a cyclic adenosine monophosphate (cAMP) analogue or both agents together. HL-60, a bipotential cell line has also been differentiated along the granulocytic pathway with DMSO and the monocytic pathway with 1,25-dihy-droxy vitamin D3. In all these systems, PLD activity increases with maturation and differentiation whatever the inducer used and the granulocytic or monocytic pathways. Increase in basal activity which reflects the expression during development of both hPLD1 and hPLD2 appears to be mainly related to the former isozyme expression. Association of PLD characteristic changes with maturation and differentiation was also con-firmed using two NB4 clones resistant to these processes. Comparison between PLD characteristics in myeloblasts during maturation and differentiation ex vivo and in vitro in the different cell lines demonstrated that NB4 induced to differentiate with ATRA represents the best model for further studies on the specific roles of each PLD isoform in various functions of differentiated myeloid cells. [ABSTRACT FROM AUTHOR]

The determination of plasma and whole blood free amino acid concentrations in arterial and portal venous blood during post prandial state in the rat was used to estimate the role of the erythrocytes in amino acid exchanges. The erythrocyte contents were calculated from plasma, whole blood concentrations and the hematocrit. The veno-arterial concentration differences in plasma were significant for all amino acids except a-aminobutyrate and ornithine whereas in the erythrocytes only 8 amino acids exhibit significant differences (ASP, ALA, VAL, MET, ILE, LEU, TYR, PHE). For 6 amino acids, a significant correlation between the plasma and the erythrocyte concentration has been found (VAL, ILE, LEU, TYR, PHE, HIS). These data suggest that in vivo during the time of contact between blood and organ tissues, some amino acids but not all are significantly taken up by the erythrocytes. Thus, it may be concluded that erythrocyte amino acid blood transport in arterio-venous portal exchanges, concerns particularly tyrosine and essential amino acids. The erythrocyte amino acid transport represents quantitatively about 20 per cent of the total blood transport. [ABSTRACT FROM AUTHOR]

Dictyostelium discoideum cells are highly resis tant to xenobiotics. We previously observed that these primitive eukaryotic cells contain a 170-kDa P-glycoprotein, mediating multidrug resistance in mammalian cells, but nonfunctional in Dictyostelium cells. We show here that D. discoideum cells vitally stained with the DNA-specific dye, Hoechst 33342, release fluorescent material in their culture medium. Electron microscopy and lipid analysis demonstrate the vesicular nature of this material. Moreover, nucleic acids associate with these extracellular vesicles independently of Hoechst vital staining. The main vesicular DNA component exhibits a size >21 kb. Shedding of microvesicles during cell growth is not concomitant with programmed cell death. We propose that these extracellular vesicles are involved in a new cellular resistance mechanism against xenobiotics. Furthermore, since the association of DNA with vesicles occurs in physiological growth conditions and independently of vital staining, the new shedding process might be involved in a more general intercellular mechanism. [ABSTRACT FROM AUTHOR]

Using peroxidase-labelled antibodies, the ultrastructural localization of IgA and secretory component (SC) was investigated in duodeno-jejunal biopsies from six children with coeliac disease and compared with that observed in non-coeliac mucosa. In normal intestinal mucosa this study confirmed the presence of IgA in the rough endoplasmic reticulum and the perinuclear space of numerous subepithelial plasma cells and on the lateral cell membranes of villous and especially crypt epithelial cells. SC was only detected in the epithelium and principally in crypt epithelium where in was identified in endoplasmic reticulum, Golgi saccules, perinuclear spaces and on lateral cell membranes. These findings support the suggestion that SC is synthesized mainly in crypt epithelium and acts as a receptor on epithelial cell membranes for dimeric IgA. In untreated coeliac patients. SC was observed at the same sites, but SC staining was reduced in damaged surface epithelial cells. The number of IgA immunocytes was increased and heavy deposits of IgA were found on basement membranes. In post-treatment biopsies, no abnormality was apparent. After re-exposure to gluten, depositions of IgA on basement membranes were the only early change. The unaltered distribution of SC and IgA in crypt epithelium strongly suggests that the epithelial transport mechanism of secretory IgA is normal in coeliac disease. [ABSTRACT FROM AUTHOR]

The article presents two case studies related to the immune-mediated necrotizing myopathies (IMNMs) in patients with autoantibodies. One case of a 20-year-old woman who showed symptoms of muscle weakness, polyarthralgia and dermatomyositis rash. Other case of a 53-year-old woman who revealed symptoms of fever, muscle weakness and dyspnoea.

The article asserts that an impaired heart rate reserve due to cardiac denervation does not play a key role in exercise limitation after heart transplantation. The author states the oxygen demand in muscular tissues is the key driving factor of cardiorespiratory adjustments during exercise. The author stresses the need to focalize directly on peripheral function rather than on the central mechanisms of oxygen transport to reverse the exercise capacity limitation observed after transplantation.

Aim: (i) evaluate carotid artery strain derived from speckle tracking ultrasound imaging (CAS) in subjects with coronary artery disease (CAD) and without coronary artery disease (N-CAD), (ii) compare CAS, to global aortic stiffness using carotid-femoral pulse wave velocity (c-f PWV) and to endothelial function using brachial flow-mediated dilatation (FMD) in subjects with CAD.Methods: 100 subjects were prospectively included, and classified into 2 groups: subjects with CAD (CAD, n=49), subjects N-CAD (N-CAD, n=51). The CAS on the common carotid artery using speckle-tracking ultrasound imaging (Vivid 7, General Electric) was measured. In the CAD, c-f PWV and FMD were evaluated and compared to CS.Results: Age of the population was 65±1.7 years. The proportion of males, diabetes and obesity in CAD was higher than N-CMD group (p=0.0005, p=0.0002, 0.0004 respectively). There was no significant difference in age and hypertension. In a multivariate analysis, age and CAD were the sole independent predictors of CAS (r=−0.6, p<0.0001; r=-0.5, p<0.0001 respectively). The CAS was significantly lower in CAD as compared to N-CAD (2.41% vs 4.48%, p<0.0001). In CAD group, 41% presented stable angina and 59 % acute coronary syndrome (ACS). The CAS was lower in stable angina vs ACS (1.85% vs 2.92%, p=0.02). In the CAD group, CAS was inversely correlated to c-f PWV (r=−0.7, p=0.0001), and correlated with endothelial dysfunction (r=0.45, p=0.003).Conclusion: Speckle-tracking ultrasound imaging is a non-invasive technique useful for the evaluation of local carotid artery stiffness. Carotid artery stiffness was higher in coronary artery disease. In CAD, carotid artery stiffness measured by speckle-tracking is associated with global aortic stiffness and endothelial dysfunction. [ABSTRACT FROM PUBLISHER]

A letter to the editor is presented in response to the Point:Counterpoint series "Flow-mediated dilation does⁄does not reflect nitric oxide-mediated endothelial function" in the September issue.

An abstract of the article "Effects of ACE Inhibition on Mitochondrial Substrates Utilization Pathways of Cardiac and Skeletal Muscles in Rats Postmyocardial Infarction," by J. Zoll and colleagues, is presented.

An abstract of the article "The Intrinsic Mitochondrial Oxidative Capacity of Human Failing Hearts Is Depressed and Relates to Disease Severity But Keeps Normal Regulatory Properties," by B. Mettauer and colleagues, is presented.