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Abstract Purpose This study aimed to investigate the differences in cement penetration between cementing techniques in total knee arthroplasty (TKA). Materials and methods We retrospectively evaluated knee undergone TKA at our hospital for both preoperative and postoperative computed tomographic (CT) evaluations. Cementing was performed with hand mixing and hand packing (HM group) and with vacuum mixing and cement gun use (VM group). We measured the area under the tibial baseplate (sclerotic and nonsclerotic sides) and compared the mean and maximum depths of cement penetration at each area. Results Of the 44 knees evaluated, 20 and 24 knees were in the HM and VM groups, respectively. At the center of the sclerotic side, the mean penetration depths (2.0 ± 0.7 and 2.5 ± 0.7 mm, p = 0.02) and the maximum penetration depths (4.0 ± 0.9 and 5.0 ± 1.6 mm, p = 0.02) were significantly deeper in the VM group than in the HM group. The correlation between preoperative Hounsfield unit values and mean penetration were r = –0.617 (p

Abstract The purpose of this study was to clarify sex differences in the inhibition of sympathetic vasomotor outflow which is caused by the loading of cardiopulmonary baroreceptors. Ten young males and ten age-matched females participated. The participants underwent a passive leg raising (PLR) test wherein they were positioned supine (baseline, 0º), and their lower limbs were lifted passively at 10º, 20º, 30º, and 40º. Each angle lasted for 3 min. Muscle sympathetic nerve activity (MSNA) was recorded via microneurography of the left radial nerve. Baseline MSNA was lower in females compared to males. MSNA burst frequency was decreased during the PLR in both males (− 6.2 ± 0.4 bursts/min at 40º) and females (− 6.5 ± 0.4 bursts/min at 40º), but no significant difference was detected between the two groups (P = 0.61). These results suggest that sex has minimal influence on the inhibition of sympathetic vasomotor outflow during the loading of cardiopulmonary baroreceptors in young individuals.

Abstract Background In systemic lupus erythematosus (SLE), autoreactive B cells are thought to develop by-passing immune checkpoints and contribute to its pathogenesis. Toll-like receptor (TLR) 7 and 9 signaling have been implicated in their development and differentiation. Although some B cell subpopulations such as T-bet + double negative 2 (DN2) cells have been identified as autoreactive in the past few years, because the upregulated surface markers of those cells are not exclusive to them, it is still challenging to specifically target autoreactive B cells in SLE patients. Methods Our preliminary expression analysis revealed that phospholipase D4 (PLD4) is exclusively expressed in plasmacytoid dendritic cells (pDCs) and B cells in peripheral blood mononuclear cells (PBMCs) samples. Monoclonal antibodies against human PLD4 were generated, and flow cytometry analyses were conducted for PBMCs from 23 healthy donors (HDs) and 40 patients with SLE. In vitro cell culture was also performed to study the conditions that induce PLD4 in B cells from HDs. Finally, recombinant antibodies were synthesized from subpopulations of PLD4 + B cells from a patient with SLE, and their antinuclear activity was measured through enzyme-linked immunosorbent assay. Results pDCs from both groups showed comparable frequency of surface PLD4 expression. PLD4 + B cells accounted for only a few percent of HD B cells, whereas they were significantly expanded in patients with SLE (2.1% ± 0.4% vs. 10.8% ± 1.2%, P

Abstract It is unclear whether blood flow restriction (BFR) accelerates the adaptation of the time constant (τ) of phase II oxygen uptake ( $$ {\dot{\text{V}}}{\text{O}}_{2} $$ V ˙ O 2 ) kinetics in the moderate-intensity exercise domain via moderate-intensity aerobic training. Therefore, healthy participants underwent moderate-intensity [45–60% $$ {\dot{\text{V}}}{\text{O}}_{2} $$ V ˙ O 2 Reserve] aerobic cycle training with or without BFR (BFR group, n = 9; CON group, n = 9) for 8 weeks to evaluate $$ {\dot{\text{V}}}{\text{O}}_{2} $$ V ˙ O 2 kinetics during moderate-intensity cycle exercise before (Pre) and after 4 (Mid) and 8 (Post) weeks of training. Both groups trained for 30 min, 3 days weekly. BFR was performed for 5 min every 10 min by applying cuffs to the upper thighs. The τ significantly decreased by Mid in the BFR group (23.7 ± 2.9 s [Pre], 15.3 ± 1.8 s [Mid], 15.5 ± 1.4 s [Post], P

Background and Aim Hypothyroidism might play a crucial role in the pathogenesis of non‐alcoholic fatty liver disease (NAFLD). The association of subclinical hypothyroidism with NAFLD has been inconsistent. The relationship of NAFLD with thyroid function parameters and subclinical hypothyroidism was determined. Methods This cross‐sectional study included 70 patients with subclinical hypothyroidism and 70 controls with euthyroidism matched according to gender, age, and body mass index (BMI). NAFLD was diagnosed via abdominal ultrasonography. The association between NAFLD and subclinical hypothyroidism was analyzed. Results The prevalence of NAFLD was significantly higher in patients with subclinical hypothyroidism than in those with euthyroidism. Multivariate analysis showed that subclinical hypothyroidism was an independent risk factor of NAFLD adjusted by metabolic‐related factors, such as BMI, triglyceride, high‐density lipoprotein‐cholesterol, hypertension, and diabetes. Thyroid‐stimulating hormone (TSH) was an independent risk factor of NAFLD adjusted by the same metabolic‐related factors, but free thyroxine (FT4) was not a risk factor. The FIB‐4 index, a noninvasive marker of liver fibrosis was significantly higher in patients with subclinical hypothyroidism than in those with euthyroidism. Compared with patients with euthyroidism, the proportion of the FIB‐4 index ≥2.67 was significantly higher, and the proportion of the FIB‐4 index

The electromyographic (EMG) activity and force relationship, i.e. EMG-force relationship, is a valuable indicator of the degree of the neuromuscular activation during isometric force production. However, there is minimal information available regarding the EMG-force relationship of individual triceps brachii (TB) muscles at different elbow joint angles. This study aimed to compare the EMG-force relationships of the medial (TB-Med), lateral (TB-Lat), and long heads (TB-Long) of the TB. 7 men and 10 women performed force matching isometric tasks at 20%, 40%, 60%, and 80%maximum voluntary contraction (MVC) at 60°, 90°, and 120° of extension. During the submaximal force matching tasks, the surface EMG signals of the TB-Med, TB-Lat, and TB-Long were recorded and calculated the root mean square (RMS). RMS of each force level were then normalized by RMS at 100%MVC. For the TB-Med, ultrasonography was used to determine the superficial region of the muscle that faced the skin surface to minimize cross-talk. The joint angle was monitored using an electrogoniometer. The elbow extension force, elbow joint angle, and surface EMG signals were simultaneously sampled at 2 kHz and stored on a personal computer. The RMS did not significantly differ between the three muscles, except between the TB-Med and TB-Lat during 20%MVC at 60°. The RMS during force levels of ≥ 60%MVC at 120° was significantly lower than that at 60° or 90° for each muscle. The sum of difference, which represents the difference in RMS from the identical line, did not significantly differ in any of the assessed muscles in the present study. This suggests that a relatively smaller neuromuscular activation could be required when the elbow joint angle was extended. However, neuromuscular activation levels and relative force levels were matched in all three TB synergists when the elbow joint angle was at 90° or a more flexed position.

The ventilatory response to moderate-intensity step load exercise has three temporal phases: an initial rapidly increasing phase I, followed by a slower exponential phase II, that leads to the steady state phase III. In muscles with mechanical hyperalgesia (delayed onset muscle soreness) and/or muscle damage a few days after eccentric exercise (ECC), an interesting phenomenon of increased ventilatory response at phases II and III during constant-load exercise and incremental exercise has been reported. However, the mechanisms behind this phenomenon have not been clarified. At least a neural mechanism is partly responsible for this phenomenon because the ventilatory response at neurally modulated phase I has been shown to be exaggerated 2 days after ECC (D2). In the present review, we focus on our previous work to identify the potential mechanism underlying the exaggerated modulation in phase I ventilatory response at D2, in which ECC-induced muscle pain is assumed to be at the peak. We also discuss the physiological and practical implications of this phenomenon.

Background: This study aimed to compare the diagnostic performance of carbohydrate-deficient transferrin (CDT) and gamma-glutamyltranspeptidase (γ-GTP) to assess the single and combined benefits of these biological markers for the detection of chronic excessive alcohol consumption in patients with alcoholic cirrhosis. Methods: Biological markers were determined in blood samples from patients with alcoholic cirrhosis (drinking group, n = 35; nondrinking group, n = 81). The prediction accuracy of %CDT alone, γ-GTP alone, and their combination for the detection of excessive alcohol consumption was determined in patients with alcoholic cirrhosis. Results: Serum total bilirubin, alanine aminotransferase, aspartate aminotransferase, γ-GTP, and alkaline phosphatase levels and %CDT were significantly higher and serum albumin levels were significantly lower in the drinking group than in the nondrinking group. The combination of %CDT and γ-GTP compared with %CDT or γ-GTP alone showed a higher prediction accuracy. The combination of %CDT and γ-GTP exhibited a higher specificity than γ-GTP alone. However, in terms of sensitivity, no significant difference was found between single or combined markers. Conclusions: The combination of %CDT and γ-GTP is considered a useful biomarker of chronic excessive alcohol consumption in patients with alcoholic cirrhosis.

Molecular targeted therapy with lenvatinib is commonly offered to advanced hepatocellular carcinoma (HCC) patients, although it is often interrupted by adverse effects which require a reduction in the initial dose. Thus, an alternative lenvatinib-based therapy to compensate for dose reduction is anticipated. This study aimed to assess the effect of combination of low-dose of lenvatinib and the angiotensin-II (AT-II) receptor blocker losartan on human HCC cell growth. In vitro studies found that losartan suppressed the proliferation by inducing G1 arrest and caused apoptosis as indicated by the cleavage of caspase-3 in AT-II-stimulated HCC cell lines (Huh-7, HLE, and JHH-6). Losartan attenuated the AT-II-stimulated production of vascular endothelial growth factor-A (VEGF-A) and interleukin-8 and suppressed lenvatinib-mediated autocrine VEGF-A production in HCC cells. Moreover, it directly inhibited VEGF-mediated endothelial cell growth. Notably, the combination of lenvatinib and losartan augmented the cytostatic and angiostatic effects of the former at a low-dose, reaching those achieved with a conventional dose. Correspondingly, a HCC tumor xenograft assay showed that the oral administration of losartan combined with lenvatinib reduced the subcutaneous tumor burden and intratumor vascularization in BALB/c nude mice. These findings support that this regimen could be a viable option for patients intolerant to standard lenvatinib dosage.

Purpose: This study aimed to identify the best single-slice anatomical muscle cross-sectional area (CSA) and muscle thickness (MT) on magnetic resonance imaging (MRI) to estimate the overall individual muscle volumes (MVs) of knee extensors and flexors in patients with knee osteoarthritis (KOA). Methods: Twelve patients (24 legs; 4 men and 8 women) with KOA underwent a 1.5-Tesla axial MRI scan in the femoral region of interest (ROI), between the lesser trochanter and rectus femoris tendon. Individual MVs were calculated by numerical integration based on individual CSAs analyzed at the ROI. The best slice was determined as follows: coefficient of determination ( R 2 ) between MVs measured and those estimated from the femoral length (FL) × CSAs or FL × MTs measured at each 10% interval level of the ROI. These estimation equations were applied for a cross-validation group (24 KOA patients: 12 men and 12 women). Results: Estimated individual MVs of knee extensors and flexors, based on the CSAs at the distal 10% level, significantly correlated with each of the measured individual MVs ( R 2 : 0.79–0.96, p < 0.05 for all). Similarly, estimated individual knee extensor MVs, based on MTs at the mid-slice, significantly correlated with each of the measured individual MVs ( R 2 : 0.77–0.84, p < 0.05 for all). The application of the developed regression equation to the cross-validation group did not exhibit any systematic bias. Conclusion: These simple methods could be applied in prospective research with a larger number of patients with KOA.

Purpose: We aimed to longitudinally investigate individual thigh muscle changes using magnetic resonance imaging (MRI) during treatment with cast of ankle or foot fracture. Moreover, we aimed to demonstrate whether measurements of muscle cross-sectional area (CSA) are sensitive to muscle changes, contributing to simpler methods in clinical application . Methods: Ten patients undergoing treatment with cast of acute ankle or foot fractures were studied. Axial MRI (1.5 T) was conducted around the affected mid-thigh region after the injury (Pre), after maintaining a nonweight-bearing (NWB) period (approximately 28 days), and after finishing rehabilitation (recovery). Regarding individual thigh muscles, the total CSAs corresponding to 40% of the femoral length (FL) and the CSAs at 5% interval of the FL were longitudinally measured. Standardized response means (SRMs) were accessed for sensitivity in the muscle changes. Results: The total CSAs at NWB were significantly lower than those at Pre in vastus lateralis (10.9% ± 5.4%), vastus intermedius (8.4% ± 6.7%), and vastus medialis (11.2% ± 6.9%) ( p < 0.01 for all). In contrast, at recovery, the only significant muscle atrophy relative to that at Pre was observed in the semitendinosus of the proximal 15% and 10% CSAs ( p < 0.01 and p = 0.01, respectively). In all muscles, SRM using a single-slice CSA at or near the muscle belly was high. Conclusion: Thigh muscle changes differ according to the variations in individual muscles. CSA measurements at or near the muscle belly are simple methods and sensitive indicators of these muscle changes.

Ventilation increases rapidly and significantly in proportion to workload or metabolic rate during dynamic exercise. This increase is called “exercise hyperpnea.” During light to moderate step load exercise, ventilation increases from the first breath and reaches a plateau within 20 s (Phase I), during which metabolites do not reach chemoreceptors; thus Phase I is solely caused by neurogenic drives. It is worthwhile to clarify the aspects of Phase I in order to identify the mechanism of neurally mediated exercise hyperpnea. Until 2000, the mechanisms of exercise hyperpnea during light to moderate step load exercise were assumed to have been derived from two conventional neurogenic drives, “central command,” coming from the motor cortex or the hypothalamus, and “peripheral neural reflex,” originating mainly from the mechanoreceptors in muscles through group III afferents. For about a century there have been a large number of experiments trying to illuminate which mechanism is the cause of exercise hyperpnea. Although central command is thought to be the more likely key source, the consensus is that both central and peripheral neurogenic drives operate ventilation redundantly, building a multiple regulation system during exercise. Recent advantages in technology have enabled us to examine exercise hyperpnea in novel ways. Peripheral neurogenic drive through group III and IV afferents again enters into the limelight by using selective blockers for these afferents without augmenting central command. The vascular distension hypothesis has advocated that a rapid increase in peripheral blood flow is sensed as a plethysmometric change by the mechanoreceptors around the venule near the contracting muscles, stimulating the respiratory center through group IV afferents so as to match ventilation with metabolic rate. On the other hand, “learning” is attracting a growing interest from a central neurogenic point of view. Two types of learning have been proposed: “long term modulation (LTM),” serotonin mediated synaptic adaptation to repeated combined exercise and other stimuli such as an increase in dead space, and “volitional control,” a behavioral and learned response with cognitive function by way of the cerebrum and cerebellum. Nevertheless, these two pathways were derived from, not direct, but circumstantial evidence. The question, “What causes ventilation to increase during exercise?” is not likely to be solved in the near future.

We hypothesized that, compared with young males, young females have a smaller decrease in blood flow to the inactive limb, accompanied by a smaller increase in arterial blood pressure, during dynamic exercise with increased inspiratory muscle work. Young males and females performed dynamic kneeextension and -flexion exercises for 10 min (spontaneous breathing for 5 min and voluntary hyperpnoea with or without inspiratory resistance for 5 min). Mean arterial blood pressure (MAP) and mean blood flow (MBF) in the brachial artery were continuously measured by means of finger photoplethysmography and Doppler ultrasound, respectively. No sex differences were found in the ΔMAP and ΔMBF (Δ: from baseline) during exercise without inspiratory resistance. In contrast, the ΔMAP during exercise with inspiratory resistive breathing was greater (P < 0.05) in males (+31.3 ± 2.1 mmHg, mean ± SE) than females (+18.9 ± 3.2 mmHg). The MBF during exercise with inspiratory resistance did not change in males (–4.4 ± 10.6 mL/min), whereas it significantly increased in females (+25.2 ± 15.4 mL/min). These results suggest that an attenuated inspiratory muscle-induced metaboreflex in young females affects blood flow distribution during submaximal dynamic leg exercise. [ABSTRACT FROM AUTHOR]

The effects of integrated word-of-mouth (WOM), both traditional and electronic, on tourism products are yet to be fully investigated. The current study aims to assess the effects of and differences between traditional WOM and electronic WOM, between personal WOM and commercial WOM, and between positive and negative WOM on a destination image. Results of the study indicate that traditional WOM had a greater influence on destination image compared to electronic WOM. Personal traditional WOM had a greater influence on destination image compared to electronic personal WOM and commercial WOM. However, negative WOM exerted less influence on the destination’s image compared to positive WOM while negative electronic WOM had a greater influence on destination image compared to negative traditional WOM.

Muscle sympathetic nerve activity (MSNA) is reduced during low-intensity dynamic leg exercise in young males. It is suggested that this inhibition is mediated by loading of the cardiopulmonary baroreceptors. The purpose of this study was to clarify the impact of age on MSNA during dynamic leg exercise. Nine younger males (YM, mean ± SD, 20 ± 1 years) and nine older males (OM, 72 ± 3 years) completed the study. The subjects performed two 4-min cycling exercises at 10% of their heart rate reserve using a cycle ergometer in a semirecumbent position (MSNA and estimated central venous pressure (eCVP) trials). MSNA was recorded via microneurography of the left radial nerve. The CVP was estimated based on peripheral venous pressure, which was monitored using a cannula in the right large antecubital vein. The magnitude of the increase in mean arterial blood pressure during leg cycling was larger in OM (+9.3 ± 5.5 mmHg) compared with YM (+2.8 ± 4.7 mmHg). MSNA burst frequency was decreased during cycling in both YM (-8.1 ± 3.8 bursts/min) and OM (-10.6 ± 3.3 bursts/min), but no significant difference was found between the two groups. The eCVP increased during exercise in both groups, and there was no difference in the changes in eCVP between YM (+1.1 ± 0.4 mmHg) and OM (+1.2 ± 0.7 mmHg). These data indicate that inhibition of sympathetic vasomotor outflow during low-intensity cycling appears inOMas seen in YM. It is possible that the muscle pump-induced loading of the cardiopulmonary baroreflex is preserved during cycling in healthy oldermales. [ABSTRACT FROM AUTHOR]

Objective: To explore the trends in patient characteristics and implant survivorship (IS) for primary total knee arthroplasty (TKA) over the past three decades. Methods: This retrospective study enrolled a total of 635 knees who underwent TKA from 1985 to 2014. They were divided into three groups: group A, 125 knees in 1985-1994; group B, 203 knees in 1995-2004; and group C, 307 knees A in 2005-2014. The patient characteristics and IS were compared. Results: The mean age of patients undergoing TKA was getting older: 65.3±9.7, 69.1 ±10.0, and 74.6 ±8.4 years, in groups A, B, and C, respectively (p = .001). The proportion of patients <60 years old with RA decreased (p<.001), whereas that of patients > 80 years old with OA increased dramatically, it was 7.0%, 14.5%, and 32.0% in groups A, B, and C, respectively (p<.001). The IS free from infection was over 98% in all groups. Alternatively, the IS free from aseptic loosening become better, it was 83.7%, 95.2%, and 98.2% in groups A, B, and C, respectively (p = .014). Conclusions: From these trends, we can estimate that the number of patients undergoing TKA will further increase in the future in an aging society. [ABSTRACT FROM AUTHOR]

Previous research has shown an exaggeration in exercise hyperpnea 2 days after eccentric exercise (ECC). Enhancement in central command has been suggested as one candidate to account for this effect given that ECC-induced neuromuscular dysfunction increases relative exercise intensity, thus resulting in reinforcement of effort sense. The purpose of this study was, therefore, to elucidate whether the degree of alteration in effort sense caused by ECC affects exercise hyperpnea. Ten subjects performed 20-s single-arm extension-flexion exercises with weight strapped to the wrist, and ventilatory response was measured before (Pre) and 2 days after ECC (D2). Relative exercise intensity at Pre was 5 % of maximal voluntary contraction (MVC) of Pre, whereas that at D2 was 9 % MVC of D2 because of decline in muscle strength. Ventilatory responses were significantly exaggerated at D2 with a significant increase in effort sense. Although effort sense was significantly reduced during exercise at D2 when wrist weight was subtracted to match relative exercise intensity at Pre (5 % MVC of D2), ventilatory responses were still significantly higher than those of Pre. After the disappearance of post-ECC muscle damage, subjects performed the same exercise with weight added (9 % MVC of Pre) so that effort was equalized to match that of D2; however, no significant increase in ventilatory response was detected. The fact that the extent of change in effort sense caused by ECC-induced neuromuscular dysfunction did not affect ventilatory response at the onset of exercise after ECC may suggest that the exaggeration of ventilatory response after ECC is caused by mechanisms other than alteration of the central command. [ABSTRACT FROM AUTHOR]

Tibetan natives have lived on the Tibetan plateau (altitude ~4,000 m) for at least 25,000 years, and as such they are adapted to life and reproduction in a hypoxic environment. Recent studies have identified two genetic loci, EGLN1 and EPAS1, that have undergone natural selection in Tibetans, and further demonstrated an association of EGLN1/EPAS1 genotype with hemoglobin concentration. Both genes encode major components of the hypoxia-inducible factor (HIF) transcriptional pathway, which coordinates an organism's response to hypoxia. Patients living at sea level with genetic disease of the HIF pathway have characteristic phenotypes at both the integrative-physiology and cellular level. We sought to test the hypothesis that natural selection to hypoxia within Tibetans results in related phenotypic differences. We compared Tibetans living at sea level with Han Chinese, who are Tibetans' most closely related major ethnic group. We found that Tibetans had a lower hemoglobin concentration, a higher pulmonary ventilation relative to metabolism, and blunted pulmonary vascular responses to both acute (minutes) and sustained (8 h) hypoxia. At the cellular level, the relative expression and hypoxic induction of HIF-regulated genes were significantly lower in peripheral blood lymphocytes from Tibetans compared with Han Chinese. Within the Tibetans, we found a significant correlation between both EPAS1 and EGLN1 genotype and the induction of erythropoietin by hypoxia. In conclusion, this study provides further evidence that Tibetans respond less vigorously to hypoxic challenge. This is evident at sea level and, at least in part, appears to arise from a hyporesponsive HIF transcriptional system. [ABSTRACT FROM AUTHOR]

This paper presents monitoring results obtained using digital, automated and optical fiber extensometers for ground surface displacement measurements in two case-studies located in the Buzău Carpathians and Subcarpathians, Romania. The main objective of this research is to accurately estimate the landslide displacement rates in order to be able to predict the time of landslide reactivation. In the case of the Colţi Church landslide (the Buzău Carpathians), correlations between displacement and precipitation are reported. In the case of the Măguricea landslide (the Buzău Subcarpathians), results obtained using a conventional extensometer (automated type) are compared with those obtained using an optical fiber system. Differences of 0.1-1mm/day were noted between displacement rates obtained using a conventional extensometer and an optical fiber system. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to clarify the influence of inspiratory resistive breathing during exercise under hypoxic conditions on muscle sympathetic nerve activity (MSNA) and blood pressure (BP). Six healthy males completed this study. The subjects performed a submaximal exercise test using a cycle ergometer in a semirecumbent position under normoxic [inspired oxygen fraction (FIO2) = 0.21] and hypoxic (FIO2 = 0.12- 0.13) conditions. The subjects carried out two 10-min exercises at 40% peak oxygen uptake [spontaneous breathing for 5 min and voluntary breathing with inspiratory resistance for 5 min (breathing frequency: 60 breaths/min, inspiratory and expiratory times were set at 0.5 s each)]. MSNA was recorded via microneurography of the right median nerve at the elbow. A progressive increase in MSNA burst frequency (BF) during leg-cycling exercise with inspiratory resistance in normoxia and hypoxia were accompanied by an augmentation of BP. The increased MSNA BF and mean arterial BP (MBP) during exercise with inspiratory resistive breathing in hypoxia (MSNA BF, 55.7 ± 1.4 bursts/min, MBP, 134.3 ± 6.6 mmHg) were higher than those in normoxia (MSNA BF, 39.2 ± 1.8 bursts/min, MBP, 123.6 ± 4.5 mmHg). These results suggest that an enhancement of inspiratory muscle activity under hypoxic condition leads to large increases in muscle sympathetic vasomotor outflow and BP during dynamic leg exercise. [ABSTRACT FROM AUTHOR]

The purpose of this study was to elucidate the influence of inspiratory muscle fatigue on muscle sympathetic nerve activity (MSNA) and blood pressure (BP) response during submaximal exercise. We hypothesized that inspiratory muscle fatigue would elicit increases in sympathetic vasoconstrictor outflow and BP during dynamic leg exercise. The subjects carried out four submaximal exercise tests: two were maximal inspiratory pressure (PImax) tests and two were MSNA tests. In the PImax tests, the subjects performed two 10-min exercises at 40% peak oxygen uptake using a cycle ergometer in a semirecumbent position [spontaneous breathing for 5 min and with or without inspiratory resistive breathing for 5 min (breathing frequency: 60 breaths/min, inspiratory and expiratory times were each set at 0.5 s)]. Before and immediately after exercise, PImax was estimated. In MSNA tests, the subjects performed two 15-min exercises (spontaneous breathing for 5 min, with or without inspiratory resistive breathing for 5 min, and spontaneous breathing for 5 min). MSNA was recorded via microneurography of the right median nerve at the elbow. PImax decreased following exercise with resistive breathing, whereas no change was found without resistance. The time-dependent increase in MSNA burst frequency (BF) appeared during exercise with inspiratory resistive breathing, accompanied by an augmentation of diastolic BP (DBP) (with resistance: MSNA, BF +83.4%; DBP, +23.8%; without resistance: MSNA BF, +19.2%; DBP, -0.4%, from spontaneous breathing during exercise). These results suggest that inspiratory muscle fatigue induces increases in muscle sympathetic vasomotor outflow and BP during dynamic leg exercise at mild intensity. [ABSTRACT FROM AUTHOR]

Purpose: To identify the effect of moderate exercise under severe hypoxia on cognitive function and the physiological factors that determine cognitive function during exercise under hypoxia. Methods: Thirteen subjects completed cognitive tasks at rest and during moderate exercise (50% peak VO2) under either normoxia or severe normobaric hypoxia (FIO2; 0.12~0.13). Peripheral oxygen saturation (SpO2), cerebral oxygenation and middle cerebral artery mean velocity (MCA VmeanM) were monitored throughout the experiment. We calculated cerebral oxygen delivery as the product of arterial oxygen content (haemoglobin concentration [Hb] × 1.36 × SpO2/100) × MCA VmeanM. Results: On average, reaction time in the cognitive task improved during exercise under both normoxia and hypoxia compared with rest (P < 0.01). However, in the hypoxic condition, ΔRT was negatively correlated with ΔSpO2 (r = −0.57, P = 0.043). Discussion: These results suggested that moderate exercise has the beneficial effect for cognitive function even under severe hypoxia. However, arterial desaturation seems to attenuate cognitive improvements during exercise under severe hypoxia. [ABSTRACT FROM AUTHOR]

Plasmacytoid dendritic cells (pDCs) link innate to acquired immune responses by producing high levels of type I IFN upon infection. In order to identify the specific genes that control pDC, we compared serial analysis of gene expression libraries from human pDCs, herpes simplex virus-stimulated pDCs and monocytes. We found that Ig-like transcript ILT7 is specifically expressed on pDC cell surfaces and is down-regulated when pDC mature in response to viral or bacterial stimulation. ILT7 expression on the cell surface required association with the Fc∊RIγ adaptor molecule. Although treatment with one anti-ILT7-specific mAb suppressed type I IFN production in response to cytosine-phosphate-guanosice (CpG) stimulation, another anti-ILT7 mAb up-regulated type I IFN production. We conclude that ILT7 is a key regulator of human pDC function. [ABSTRACT FROM AUTHOR]