Inhibition of fibrotic changes in infrapatellar fat pad alleviates persistent pain and articular cartilage degeneration in monoiodoacetic acid-induced rat arthritis model

OBJECTIVE

We have reported that fibrotic changes in infrapatellar fat pad (IFP) after acute joint inflammation are closely associated with persistent pain in rats. In this study, to examine the effects of anti-fibrotic treatment on persistent pain, we used C-type natriuretic peptides (CNP) at the recovery phase after acute joint inflammation.

DESIGN

Thirty-two male Wistar rats were used in this study. Monoiodoacetic acid (MIA) was injected intra-articularly to induce IFP fibrosis and persistent pain. CNP was injected after acute inflammatory phase in the same knee joint. Time-course pain-avoidance behavior tests and histological analyses were performed to examine the effects of CNP.

RESULTS

Histological evaluations indicated that intra-articular injection of CNP inhibited fibrotic changes in IFP after acute inflammation. Incapacitance tests indicated that MIA injection into rat knee joint quickly decreased the percent weight on ipsilateral limb. In the vehicle group, the decrease was maintained up to day 28, suggesting that pain persistence occurred after acute inflammation (Day 0/Day 28, Est Dif -8.15, CI -10.78∼-5.53, Linear mixed-effect model). In contrast, the pain was alleviated in the CNP group after day 14 (Day0/Day 14, -0.51, -2.62-1.59). In addition, we observed significant improvement in the degree of articular cartilage degeneration at day 14 in the CNP group (OARSI score: vehicle 16.14 ± 4.37 vs CNP 6.87 ± 3.44, P < 0.01; Wilcoxon rank sum test).

CONCLUSION

Fibrotic changes in IFP may play important roles in both persistent pain and articular cartilage degeneration.

The atypical mitogen-activated protein kinase ERK3 is essential for establishment of epithelial architecture

Epithelia contribute to physical barriers that protect internal tissues from the external environment and also support organ structure. Accordingly, establishment and maintenance of epithelial architecture are essential for both embryonic development and adult physiology. Here, using gene knockout and knockdown techniques along with gene profiling, we show that extracellular signal-regulated kinase 3 (ERK3), a poorly characterized atypical mitogen-activated protein kinase (MAPK), regulates the epithelial architecture in vertebrates. We found that in Xenopus embryonic epidermal epithelia, ERK3 knockdown impairs adherens and tight-junction protein distribution, as well as tight-junction barrier function, resulting in epidermal breakdown. Moreover, in human epithelial breast cancer cells, inhibition of ERK3 expression induced thickened epithelia with aberrant adherens and tight junctions. Results from microarray analyses suggested that transcription factor AP-2α (TFAP2A), a transcriptional regulator important for epithelial gene expression, is involved in ERK3-dependent changes in gene expression. Of note, TFAP2A knockdown phenocopied ERK3 knockdown in both Xenopus embryos and human cells, and ERK3 was required for full activation of TFAP2A-dependent transcription. Our findings reveal that ERK3 regulates epithelial architecture, possibly together with TFAP2A.

Comparison of wear rate and osteolysis between second-generation annealed and first-generation remelted highly cross-linked polyethylene in total hip arthroplasty. A case control study at a minimum of five years

BACKGROUND

There is no previous report that directly compared wear resistance of second-generation annealed highly cross-linked polyethylene with that of first-generation remelted highly cross-linked polyethylene. We therefore performed a retrospective study at a minimum of 5-year follow-up comparing second-generation annealed and first-generation remelted highly cross-linked polyethylene in order to: (1) assess wear rates and (2) compare the incidence of osteolysis between, (3) identify the frequency of complication related to the two types of highly cross-linked polyethylene.

HYPOTHESIS

There is a difference in the linear wear rate and the incidence of osteolysis between the two types of highly cross-linked polyethylene in total hip arthroplasty.

MATERIALS AND METHODS

In a single centre study, we reviewed 123 primary cementless total hip arthroplasties between 2010 and 2011 that were performed with 32mm alumina ceramic on second-generation annealed (X3) or first-generation remelted (Longevity) highly cross-linked polyethylene liner. There was no specific reason for the choice of the type of highly cross-linked polyethylene. There were no significant differences between the two groups in respect of gender, diagnosis, body mass index, pre- and post-operative functional and activity score, cup size, and cup orientation except the younger age in the X3 group. The mean wear rate and the incidence of osteolysis were evaluated at the latest follow-up.

RESULTS

One hundred nine cases followed over 5 years post-operatively (88.6% in all consecutive cases) were evaluated. X3 and Longevity were used in 54 and 55 cases, respectively. The mean follow-up was 5.3 years in both groups. The mean linear wear rate of X3 and Longevity group was 0.045±0.023mm/year and 0.076±0.031mm/year, respectively (P<0.001). No osteolysis was found on plain X-rays in both groups and no specific complication was related to these highly cross-linked components.

DISCUSSION

Excellent wear resistance of both types of highly cross-linked polyethylene liner was revealed in our study. The difference of wear rate between two materials should be monitored in a longer follow-up.

LEVEL OF EVIDENCE

Level III retrospective case control study.

Efficiency of genomic selection for breeding population design and phenotype prediction in tomato

Genomic selection (GS), which uses estimated genetic potential based on genome-wide genotype data for a breeding selection, is now widely accepted as an efficient method to improve genetically complex traits. We assessed the potential of GS for increasing soluble solids content and total fruit weight of tomato. A collection of big-fruited F1 varieties was used to construct the GS models, and the progeny from crosses was used to validate the models. The present study includes two experiments: a prediction of a parental combination that generates superior progeny and the prediction of progeny phenotypes. The GS models successfully predicted a better parent even if the phenotypic value did not vary substantially between candidates. The GS models also predicted phenotypes of progeny, although their efficiency varied depending on the parental cross combinations and the selected traits. Although further analyses are required to apply GS in an actual breeding situation, our results indicated that GS is a promising strategy for future tomato breeding design.

ERK7 regulates ciliogenesis by phosphorylating the actin regulator CapZIP in cooperation with Dishevelled

Cilia are essential for embryogenesis and maintenance of homeostasis, but little is known about the signalling pathways that regulate ciliogenesis. Here, we identify ERK7, an atypical mitogen-activated protein kinase, as a key regulator of ciliogenesis. ERK7 is strongly expressed in ciliated tissues of Xenopus embryos. ERK7 knockdown markedly diminishes both the number and the length of cilia in multiciliated cells, and it inhibits the apical migration of basal bodies. Moreover, ERK7 knockdown results in a loss of the apical actin meshwork, which is required for the proper migration of basal bodies. We find that the actin regulator CapZIP, which has been shown to regulate ciliogenesis in a phosphorylation-dependent manner, is an ERK7 substrate, and that Dishevelled, which has also been shown to regulate ciliogenesis, facilitates ERK7 phosphorylation of CapZIP through binding to both ERK7 and CapZIP. Collectively, these results identify an ERK7/Dishevelled/CapZIP axis that regulates ciliogenesis.

Identification and characterization of retinoic acid-responsive genes in mouse kidney development

Retinoic acid (RA) signaling regulates a variety of developmental processes through controlling the expression of numerous genes. Here, we have identified and characterized RA-responsive genes in mouse kidney development. Analysis of isolated embryonic kidneys cultured in the presence and absence of RA identified 33 candidates of RA-responsive genes. Most of these candidate genes were down-regulated by treatment with the RA receptor antagonist. Many of them have potential binding sites for Elf5, one of the RA-responsive genes, in their promoter region. Whole-mount in situ hybridization showed that specific expression of Elf5 in the ureteric trunk depends on RA. RA-dependent expression in the ureteric trunk was also showed for the sodium channel subunit Scnn1b, which has been shown to be the marker gene of the collecting duct. In contrast, the expression of Ecm1, Tnfsf13b and IL-33 was detected in the stromal mesenchymal cells. Both Tnfsf13b and IL-33 were previously shown to cause nuclear factor κB (NF-κB) activation. We have showed that the inhibition of NF-κB signaling with specific inhibitors suppresses branching morphogenesis of the ureteric bud. Our study thus identifies and characterizes RA-dependent up-regulated genes in kidney development, and suggests an involvement of NF-κB signaling in the branching morphogenesis.

HIRA, a conserved histone chaperone, plays an essential role in low-dose stress response via transcriptional stimulation in fission yeast

Cells that have been pre-exposed to mild stress (priming stress) acquire transient resistance to subsequent severe stress even under different combinations of stresses. This phenomenon is called cross-tolerance. Although it has been reported that cross-tolerance occurs in many organisms, the molecular basis is not clear yet. Here, we identified slm9(+) as a responsible gene for the cross-tolerance in the fission yeast Schizosaccharomyces pombe. Slm9 is a homolog of mammalian HIRA histone chaperone. HIRA forms a conserved complex and gene disruption of other HIRA complex components, Hip1, Hip3, and Hip4, also yielded a cross-tolerance-defective phenotype, indicating that the fission yeast HIRA is involved in the cross-tolerance as a complex. We also revealed that Slm9 was recruited to the stress-responsive gene loci upon stress treatment in an Atf1-dependent manner. The expression of stress-responsive genes under stress conditions was compromised in HIRA disruptants. Consistent with this, Pol II recruitment and nucleosome eviction at these gene loci were impaired in slm9Δ cells. Furthermore, we found that the priming stress enhanced the expression of stress-responsive genes in wild-type cells that were exposed to the severe stress. These observations suggest that HIRA functions in stress response through transcriptional regulation.

A molecular mechanism that links Hippo signalling to the inhibition of Wnt/β-catenin signalling

The Hippo signalling pathway has emerged as a key regulator of organ size, tissue homeostasis, and patterning. Recent studies have shown that two effectors in this pathway, YAP/TAZ, modulate Wnt/β-catenin signalling through their interaction with β-catenin or Dishevelled, depending on biological contexts. Here, we identify a novel mechanism through which Hippo signalling inhibits Wnt/β-catenin signalling. We show that YAP and TAZ, the transcriptional co-activators in the Hippo pathway, suppress Wnt signalling without suppressing the stability of β-catenin but through preventing its nuclear translocation. Our results show that YAP/TAZ binds to β-catenin, thereby suppressing Wnt-target gene expression, and that the Hippo pathway-stimulated phosphorylation of YAP, which induces cytoplasmic translocation of YAP, is required for the YAP-mediated inhibition of Wnt/β-catenin signalling. We also find that downregulation of Hippo signalling correlates with upregulation of β-catenin signalling in colorectal cancers. Remarkably, our analysis demonstrates that phosphorylated YAP suppresses nuclear translocation of β-catenin by directly binding to it in the cytoplasm. These results provide a novel mechanism, in which Hippo signalling antagonizes Wnt signalling by regulating nuclear translocation of β-catenin.

Professional Oral Health Care Reduces the Number of Oropharyngeal Bacteria

Silent aspiration of oropharyngeal pathogenic organisms is a significant risk factor causing pneumonia in the elderly. We hypothesized that regular oral hygiene care will affect the presence of oropharyngeal bacteria. Professional cleaning of the oral cavity and/or the gargling of a disinfectant liquid solution was performed over a five-month period in three facilities for the dependent elderly. Total oropharyngeal bacteria, streptococci, staphylococci, Candida, Pseudomonas, and black-pigmented Bacteroides species were monitored. The levels of these oropharyngeal bacteria decreased or disappeared after weekly professional oral health care, i.e., cleaning of teeth, dentures, tongue, and oral mucous membrane by dental hygienists. After lunch, gargling with povidone iodine was shown to be less effective than professional oral care. These findings indicate that weekly professional mechanical cleaning of the oral cavity, rather than a daily chemical disinfection of the mouth, can be an important strategy to prevent aspiration pneumonia in the dependent elderly.

Heart-type fatty acid binding protein is a novel prognostic marker in patients with non-ischaemic dilated cardiomyopathy

OBJECTIVE

To determine whether concentrations of heart-type fatty acid binding protein (H-FABP) measured before hospital discharge predict critical cardiac events in patients with idiopathic dilated cardiomyopathy (DCM).

PATIENTS

92 consecutive patients with DCM were enrolled and followed up for four years.

MAIN OUTCOME MEASURES

Serum concentrations of H-FABP, brain natriuretic peptide (BNP), cardiac troponin T before hospital discharge and survival rate.

RESULTS

23 patients died of cardiac causes, received a left ventricular assist device or underwent heart transplantation during the four-year follow up. Univariate analyses showed that New York Heart Association functional class, heart rate, ejection fraction, serum H-FABP and plasma BNP were significant variables. According to multivariate analysis, serum H-FABP and plasma BNP concentrations were independent predictors of critical cardiac events. Cardiac troponin T before hospital discharge was not a predictor. The area under the receiver operating characteristic curve for death from critical cardiac events was similar between H-FABP and BNP. Patients with an H-FABP concentration at or above the median (> or = 5.4 ng/ml) had a significantly lower survival rate than those below the median, according to analysis by log rank test (p < 0.0001). When combined with BNP concentration at or above the median (> or = 138 pg/ml), H-FABP below the median predicted the worst prognosis among the combinations.

CONCLUSIONS

The concentration of serum H-FABP before discharge from hospital may be an independent predictor for critical cardiac events in DCM.

Recovery, morphological quality, and in vitro maturation of follicular oocytes from bitches with pyometra

The objective of this study was to collect oocytes from ovaries of bitches with pyometra and to characterize the quality of the oocytes recovered. In 10 of 12 cases of pyometra, follicles with a diameter of 500 microm to 1mm were observed in the ovaries. A total of 710 oocytes were collected from 10 bitches by puncturing individual follicles after slicing the ovarian tissues. Oocyte recovery was successful from a bitch with severe clinical signs of pyometra. Of the oocytes collected, 53.5% were surrounded by > or =2 layers of cumulus cells, and 55.0% of these cumulus-oocyte complexes (COCs) had a darkly pigmented ooplasm >110 microm in diameter (large-dark COCs). The number of large-dark COCs per bitch varied from 1 to 72. A germinal vesicle with fine filaments of chromatin (Type A) was observed in 51.8% (range 21.1-100%) of the oocytes of large-dark COCs. Out of 50 oocytes cultured for 72 h, 6.0% developed to Metaphase II. In conclusion, there were many follicles with a diameter of 500 microm to 1mm in ovaries of bitches with pyometra, and many oocytes recovered from these follicles underwent meiotic maturation in vitro. The number of oocytes and COCs, and the morphological quality of the germinal vesicles varied among individual bitches.

Identifying patterns of spatial current dispersion that characterise and separate the Brugada syndrome and complete right-bundle branch block

The aim of the study was to detect patterns of spatial-current distribution in the late QRS and early ST-segments that distinguish Brugada-syndrome cases from complete right-bundle branch block (CRBBB). Magnetocardiograms (MCGs) were recorded from Brugada-syndrome patients (n = 6), CRBBB patients (n = 4) and the members of a control group (n = 33). The current distributions at six time points from Q-onset were estimated by producing current-arrow maps (CAMs). The angle of the current arrow of maximum amplitude at each time point was calculated. In the Brugada cases, the characteristic ST elevation was seen above the upper right chest, and abnormal currents appeared to be present in the right-ventricular outflow tract (RVOT). The angles of the abnormal arrows were -78 degrees +/- 51 degrees at 100 ms and -50 degrees +/- 61 degrees at 110 ms. In the cases of CRBBB, wide S- and R-waves were recorded above the upper right and lower right chest, respectively. The angles of the abnormal arrows for CRBBB were 152 degrees +/- 19 degrees at 100 ms, 159 degrees +/- 20 degrees at 110 ms, and 157 degrees +/- 19 degrees at 120 ms. The findings suggest that an abnormal current from the RVOT to the upper left chest may be a feature of the Brugada syndrome, and that the direction of this current is completely different from that seen in CRBBB.

Mechanism of improvement in exercise capacity after the maze procedure combined with mitral valve surgery

OBJECTIVE

To clarify the mechanism of improvement in exercise capacity after the maze procedure.

DESIGN

Retrospective study.

SETTING

Tertiary referral centre.

PATIENTS

26 patients (mean (SD) age 57 (9) years) with atrial fibrillation (AF) and mitral valve disease were studied with echocardiography and cardiopulmonary exercise testing before and after the maze procedure combined with mitral valve surgery. Of these, eight had persistent AF and 18 had restored sinus rhythm (SR) by the surgery. Six patients (mean (SD) age 59 (12) years) with AF undergoing mitral valve surgery without the maze procedure who had cardiopulmonary exercise testing before and after the surgery formed the control group.

MAIN OUTCOME MEASURES

Echocardiographic parameters of atrial function were measured from transmitral flow recordings. Peak oxygen uptake (VO2) and the slope of the relation between VO2 and workload (ratio of DeltaVO2 to Delta work) were determined as indices of exercise capacity.

RESULTS

The degree of improvements in peak VO2 and the ratio of DeltaVO2 to Delta work after the mitral valve surgery was comparable between the maze and control group. It was also comparable between patients with and those without successfully restored SR after the maze procedure. The degree of the increase in peak VO2 correlated with the change in left atrial diameter (r = -0.40, p = 0.047) but atrial contraction did not correlate with the increase.

CONCLUSIONS

Improvement in exercise capacity may not be caused by restored SR and atrial contraction but may at least partly relate to the reduction of left atrial size and improvement of haemodynamic variables by the surgery.

A chitinase with high activity toward partially N-acetylated chitosan from a new, moderately thermophilic, chitin-degrading bacterium, Ralstonia sp. A-471

A moderately thermophilic bacterium, strain A-471, capable of degrading chitin was isolated from a composting system of chitin-containing waste. Analysis of the 16S rDNA sequence revealed that the bacterium belongs to the genus Ralstonia. A thermostable chitinase A ( Ra-ChiA) was purified from culture fluid of the bacterium grown in colloidal chitin medium. Purification of the enzyme was achieved mainly by exploiting its binding to the colloidal chitin. The molecular mass of the enzyme was estimated to be 70 kDa and the isoelectric point approximately 4.7. N-terminal amino acid sequencing revealed a sequence of ADPYLKVAYYP, which had high homology (66% identity) with that of chitinase A1 from Bacillus circulans WL-12. The pH and temperature optima were determined to be 5.0 and 70 degrees C, respectively. The enzyme was classified as a retaining glycosyl hydrolase and was most active against partially N-acetylated chitosans. Its activities towards the partially N-acetylated chitosans, i.e. chitosan 7B, chitosan 8B, and chitosan 9B, were about 11-fold, 9-fold, and 5-fold higher than towards colloidal chitin, respectively. Ra-ChiA cleaved (GlcNAc)6 almost exclusively into (GlcNAc)2. Activation of Ra-ChiA was observed by the addition of 1 mM Cu2+, Mn2+, Ca2+, or Mg2+. Degradation of the partially N-acetylated chitosan produced oligosaccharides with a degree of polymerization ranging from 1-8; these are products that offer potential application for functional oligosaccharide production.

Oral beraprost sodium improves exercise capacity and ventilatory efficiency in patients with primary or thromboembolic pulmonary hypertension

OBJECTIVE

To investigate the effect of beraprost sodium, an orally active prostacyclin analogue, on exercise capacity and ventilatory efficiency in patients with primary pulmonary hypertension and chronic thromboembolic pulmonary hypertension.

PATIENTS AND DESIGN

Symptom limited cardiopulmonary exercise testing was performed before and 3 (1) months (mean (SEM)) after beraprost treatment in 30 patients with precapillary pulmonary hypertension (14 with primary pulmonary hypertension and 16 with chronic thromboembolic pulmonary hypertension).

RESULTS

Long term treatment with beraprost resulted in significant increases (mean (SEM)) in peak workload (87 (4) W to 97 (5) W, p < 0.001) and peak oxygen consumption (peak VO2, 14.9 (0.7) ml/kg/min to 16.8 (0.7) ml/kg/min, p < 0.001). Beraprost decreased the ventilatory response to carbon dioxide production during exercise (VE-VCO2 slope, 42 (2) to 37 (1), p < 0.001). No significant difference in the responses of these variables to beraprost treatment was observed between patients with primary pulmonary hypertension and chronic thromboembolic pulmonary hypertension.

CONCLUSIONS

Oral administration of beraprost sodium may improve exercise capacity and ventilatory efficiency in patients with both primary and chronic thromboembolic pulmonary hypertension.

Cobalamin deficiency results in severe metabolic disorder of serine and threonine in rats

Dietary cobalamin (vitamin B12; Cbl) deficiency caused significant increases in plasma serine, threonine, glycine, alanine, tyrosine, lysine and histidine levels in rats. In particular, the serine and threonine levels were over five and eight times, respectively, higher in the Cbl-deficient rats than those in the sufficient controls. In addition, some amino acids, including serine and threonine, were excreted into urine at significantly higher levels in the deficient rats. When Cbl was supplemented into the deficient rats for 2 weeks, in coincidence with the disappearance of the urinary excretion of methylmalonic acid (an index of Cbl deficiency), the plasma serine and threonine levels were normalized. These results indicate that Cbl deficiency results in metabolic disorder of certain amino acids, including serine and threonine. The expression level of hepatic serine dehydratase (SDH), which catalyzes the conversion of serine and threonine to pyruvate and 2-oxobutyrate, respectively, was significantly lowered by Cbl deficiency, even though Cbl does not participate directly in the enzyme reaction. The SDH activity in the deficient rats was less than 20% of that in the sufficient controls, and was normalized 2 weeks after the Cbl supplementation. It is thus suggested that the decrease of the SDH expression relates closely with the abnormalities in the plasma and urinary levels of serine and threonine in the Cbl-deficient rats.

Hemodynamic, renal, and hormonal effects of ghrelin infusion in patients with chronic heart failure

Ghrelin is a novel GH-releasing peptide that may also induce vasodilation and a positive energy balance through GH-independent mechanisms. However, the hemodynamic, renal, and hormonal effects of ghrelin in patients with chronic heart failure (CHF) remain unknown. Accordingly, 12 patients with CHF were given an iv infusion of human ghrelin (0.1 microg/kg.min) or placebo. Ghrelin significantly decreased mean arterial pressure (-9 mm Hg, P < 0.05) without a significant change in heart rate. Ghrelin significantly increased cardiac index (+25%, P < 0.05) and stroke volume index (+30%, P < 0.05), although it did not significantly alter mean pulmonary arterial pressure or pulmonary capillary wedge pressure. Infusion of ghrelin induced a marked increase in serum GH level (15-fold), associated with slight increases in circulating epinephrine, ACTH, cortisol, and PRL. Infusion of ghrelin did not significantly alter urine volume, urinary sodium excretion, or creatinine clearance. These hemodynamic, renal and hormonal parameters remained unchanged during placebo infusion. In summary, iv infusion of ghrelin, a potent GH-releasing peptide, had beneficial hemodynamic effects in patients with CHF in the absence of renal effects.

Comparative left ventricular functional and neurohumoral effects of chronic treatment with carvedilol versus metoprolol in patients with dilated cardiomyopathy

The efficacy of treating dilated cardiomyopathy with metoprolol was compared with that of carvedilol. Metoprolol was administered to 29 patients, and carvedilol to 62. Patients who could not be dosed with up to 40 mg daily of metoprolol or 20 mg daily of carvedilol were defined as intolerant. As well as the tolerability of these beta-blockers, the effects on left ventricular end-diastolic dimension (LVDd), fractional shortening (FS), plasma atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) concentrations, the delayed heart and mediastinum (H/M) ratio determined from metaiodobenzylguanidine imaging were compared. Drug intolerance occurred in 24% of patients in the metoprolol group and 19% in the carvedilol group. Among the drug-tolerant patients, LVDd, FS and plasma BNP concentration improved in both groups and to the same degree. Only 25% of drug-tolerant patients in the metoprolol group had a delayed H/M ratio below 1.9 compared with 57% in the carvedilol group. Both metoprolol and carvedilol, when tolerated, improve cardiac function and neurohumoral factors to the same degree. However, carvedilol is preferable to metoprolol for patients with a low delayed H/M ratio.

Effects of CO2 and O2 concentrations and light intensity on growth of microalgae (Euglena gracilis) in CELSS

Green microalgae are likely to play an important role in bioregenerative systems for producing food and converting CO2 to O2 in a controlled ecological life support system (CELSS). In the present study, a method for evaluating the effects of environmental variables on the multiplication rate of microalgal cells was developed to determine the optimum culture condition for a microalgal culture system that can function effectively in the CELSS. The microalga, Euglena gracilis, was cultured in water droplets (3 microliters in liquid volume each) in a vessel (25 ml in air volume) in which the CO2 and O2 concentrations were controlled. The number of Euglena cells cultured at CO2 concentrations ranging from 2% to 6%, O2 concentrations ranging from 5% to 20%, and PPF levels ranging from 50 to 100 micromoles m-2 s-1 was monitored by using a video camera and a microscope. The multiplication rate of cells was highest and the cell number increased by 8.3 times during 48 h under a condition of 4% CO2, 21% O2 and 100 micromoles m-2 s-1 PPF. The multiplication rate of the cells was highest at 4% CO2, followed by 6% and 2% CO2, and it decreased with decreasing O2 concentration and decreasing PPF.

Serial assessment of left and right ventricular filling in patients with congestive heart failure

Serial changes in the diastolic filling of both ventricles were studied using Doppler echocardiography in 19 patients with congestive heart failure from the acute to the convalescent stage. During the acute stage, left ventricular early filling velocity (E) was high (88 +/- 17 cm/s) and atrial filling velocity (A) was low (44 +/- 23 cm/s), whereas the right ventricular E was depressed (17 +/- 8 cm/s) and A was enhanced (40 +/- 9 cm/s). As the condition improved, left ventricular E decreased (43 +/- 11 cm/s, p < 0.01) and A increased (59 +/- 24 cm/s, p < 0.01) along with a decrease in the left ventricular and atrial dimensions. In contrast to the changes in left ventricular filling, right ventricular E increased (31 +/- 10 cm/s, p < 0.01) and A decreased (32 +/- 5 cm/s, p < 0.05). There are opposite directional changes in left and right ventricular filling with clinical improvement from the acute to the convalescent stage of congestive heart failure, which suggest that the changes are related to improvement of the hemodynamic conditions of both ventricles. The changes in the right ventricular filling pattern was likely to be related to changes in right ventricular afterload, ventricular interaction and external constraint rather than a change in right ventricular filling pressure.

Vascular cell adhesion molecule-1 as a biochemical marker of left ventricular mass in the patients with hypertension

Plasma levels of soluble intercellular adhesion molecule-1 (sICAM-1), vascular adhesion molecule-1 (sVCAM-1), and E-selectin were measured in 80 outpatients with uncomplicated essential hypertension. Although the levels of E-selectin and sICAM-1 were similar between the patients with and without left ventricular (LV) hypertrophy, sVCAM-1 level was significantly elevated in the patients with LV hypertrophy (759.7+/-154.6 ng/mL nu 984.4+/-240.6 ng/mL, P < .0001). The LV mass normalized to body surface area or height were significantly correlated with sVCAM-1 (r=0.615, P < .0001 and r=0.571, P < .0001, respectively). These results indicate that a soluble adhesion molecule is correlated with LV mass in uncomplicated essential hypertensive patients.

Clinical analysis of myocardial perfusion and metabolism in patients with hypertrophic cardiomyopathy by single photon emission tomography and positron emission tomography

BACKGROUND AND OBJECTIVES

Changes in myocardial energy metabolism and their relation to coronary flow reserve in hypertrophic cardiomyopathy were assessed by myocardial fatty acid imaging with iodine-123 beta-methyliodophenyl pentadecanoic acid single photon emission tomography (123I-BMIPP SPECT) (fasting), glucose imaging with fluorine-18 fluorodeoxyglucose positron emission tomography (18F-FDG PET) (fasting), and perfusion imaging with nitrogen-13 (13N)-ammonia PET (dipyridamole-stress and at rest) in adult patients with hypertrophic cardiomyopathy and with asymmetric septal hypertrophy.

RESULTS

123I-BMIPP defects mismatched with thallium-201 (201Tl) uptake were often observed in the hypertrophic septal regions indicating reduced fatty acid utilization incidence of 59% (22/37). 18F-FDG images showed diffusely increased uptake in most of the patients (73%, 27/37), but showed regionally increased 18F-FDG uptake at the septal regions in only two patients. Study of 18 hypertrophic cardiomyopathy patients with the mismatched 123I-BMIPP defects found that the severity of the defects correlated with reduced coronary flow reserve determined by the 13N-ammonia PET study. On the other hand, changes in 18F-FDG images were not related to those in coronary flow reserve.

CONCLUSIONS

These results suggest that the mismatched 123I-BMIPP defects, which indicate abnormality in myocardial fatty acid metabolism, occur under reduced coronary flow reserve, and may contribute to the prediction of progressive myocardial failure in patients with hypertrophic cardiomyopathy. The significance of 18F-FDG in patients with hypertrophic cardiomyopathy is still uncertain.

Acute and chronic effects of surgical thromboendarterectomy on exercise capacity and ventilatory efficiency in patients with chronic thromboembolic pulmonary hypertension

OBJECTIVE

To assess acute and chronic effects of surgical thromboendarterectomy on exercise capacity and ventilatory efficiency in patients with chronic thromboembolic pulmonary hypertension (CTEPH).

DESIGN

Cardiopulmonary exercise testing was performed in 20 patients with CTEPH before thromboendarterectomy (baseline), one month after (early phase), and four months after (late phase). Peak oxygen uptake (peak VO(2)) and the ventilatory response to carbon dioxide production (VE-VCO(2) slope) were measured for assessment of exercise capacity and ventilatory efficiency. Right heart catheterisation was performed in all patients before and one month after surgery.

RESULTS

Baseline peak VO(2) decreased and VE-VCO(2) slope increased along with the increase in pulmonary vascular resistance in patients with CTEPH. After thromboendarterectomy, the VE-VCO(2) slope decreased greatly from baseline to the early phase (mean (SD), 50 (9) to 37 (7), p < 0.05) and reached a steady level thereafter. In contrast, a continued increase in peak VO(2) was noted from the early to the late phase (16.9 (4.1) to 21.1 (5.0) ml/kg/min, p < 0.05). The decrease in the VE-VCO(2) slope from baseline to the early phase, but not the increase in peak VO(2), correlated strongly with the decrease in pulmonary vascular resistance after surgery (r = 0.75, p < 0.01).

CONCLUSIONS

Thromboendarterectomy may cause an immediate improvement in ventilatory efficiency, possibly through its beneficial haemodynamic effects. In contrast, exercise capacity may continue to improve towards the late phase, reflecting peripheral adaptation to exercise.

Acute and chronic effects of surgical thromboendarterectomy on exercise capacity and ventilatory efficiency in patients with chronic thromboembolic pulmonary hypertension

OBJECTIVE

To assess acute and chronic effects of surgical thromboendarterectomy on exercise capacity and ventilatory efficiency in patients with chronic thromboembolic pulmonary hypertension (CTEPH).

DESIGN

Cardiopulmonary exercise testing was performed in 20 patients with CTEPH before thromboendarterectomy (baseline), one month after (early phase), and four months after (late phase). Peak oxygen uptake (peakV˙o2) and the ventilatory response to carbon dioxide production (V˙e-V˙co2 slope) were measured for assessment of exercise capacity and ventilatory efficiency. Right heart catheterisation was performed in all patients before and one month after surgery.

RESULTS

Baseline peakV˙o2 decreased andV˙e-V˙co2 slope increased along with the increase in pulmonary vascular resistance in patients with CTEPH. After thromboendarterectomy, theV˙e-V˙co2 slope decreased greatly from baseline to the early phase (mean (SD), 50 (9) to 37 (7), p < 0.05) and reached a steady level thereafter. In contrast, a continued increase in peak V˙o2 was noted from the early to the late phase (16.9 (4.1) to 21.1 (5.0) ml/kg/min, p < 0.05). The decrease in theV˙e-V˙co2 slope from baseline to the early phase, but not the increase in peakV˙o2, correlated strongly with the decrease in pulmonary vascular resistance after surgery (r = 0.75, p < 0.01).

CONCLUSIONS

Thromboendarterectomy may cause an immediate improvement in ventilatory efficiency, possibly through its beneficial haemodynamic effects. In contrast, exercise capacity may continue to improve towards the late phase, reflecting peripheral adaptation to exercise.

Oral health care status of homebound elderly in Japan

We examined the present conditions of oral health care in order to contribute towards an effective system to provide oral health care for homebound elderly in Japan. A questionnaire was mailed to homebound elderly subjects (n=908) and returned by mail. A 73.6% response was achieved. The questionnaire was designed to elicit information with respect to the general condition of the subjects and independence of oral health care. About 70% of the subjects were chair- or bed-bound. Among all subjects, 37.6% required partial or full assistance on toothbrushing, 55.6% on cleaning dentures and 46.7% on eating. The degree of oral health care tended to be poor for chair- or bed-bound elderly compared with independent or house-bound elderly. Homebound elderly with lower Activities of Daily Living Scale (ADL) required more support for oral health care compared with elderly with higher ADL.

An enhanced method for left ventricular volume and ejection fraction by triggered harmonic contrast echocardiography

To elucidate the validity and reproducibility of the use of intravenous echo-contrast agent in the evaluation of left ventricular (LV) performance, we measured LV volume and ejection fraction (EF) in 42 patients with triggered harmonic contrast imaging (THCI), compared with continuous harmonic imaging without contrast agent (CHI) and with cineventriculography (CVG). In 10 of 42 patients, THCI improved LV border delineation which could not be obtained even with CHI. LV end-diastolic, end-systolic volumes and EF by both CHI and THCI correlated well with those by CVG. Although LV volumes are underestimated, THCI lessened the mean differences to about in half, compared with CHI. The observer variabilities obtained using THCI were smaller than those by CHI. These results indicate the validity of LV enhancement and the measurement of EF using THCI. We suggest that this method noninvasively provides more accurate LV systolic function with the acceptable reproducibility.

[Clinical significance of measuring inferior vena cava dimension in patients with acute exacerbation of chronic heart failure]

OBJECTIVES

This study determined the clinical significance of measuring the inferior vena cava dimension in patients with heart failure.

METHODS

The subjects were 373 patients admitted due to acute exacerbation of chronic heart failure. The relationships were examined between inferior vena cava dimension in the end-expiratory phase on admission and in the stable state and etiology of heart failure, age, New York Heart Association (NYHA) functional classification in the stable state (before exacerbation), body weight, grade of tricuspid regurgitation, left ventricular end-diastolic dimension and left ventricular ejection fraction measured by two-dimensional echocardiography in the stable state and on admission, severity of lung congestion (Killip's classification) on admission, and clinical course during treatment.

RESULTS

The inferior vena cava dimension was not correlated with etiology, age, NYHA functional classification, body weight, left ventricular end-diastolic dimension or left ventricular ejection fraction, but was correlated with the grade of tricuspid regurgitation (r = 0.78, p < 0.0001 in the stable state, r = 0.60, p < 0.0001 and on admission). The severity of lung congestion did not correlate with inferior vena cava dimension on admission or the increase in inferior vena cava dimension. The increase in body weight on admission was correlated with the increase in inferior vena cava dimension (r = 0.83, p < 0.0001), but did not correlate with inferior vena cava dimension on admission. Tricuspid regurgitation grade and inferior vena cava dimension were restored to the stable state when body weight reached stable state after treatment in patients (n = 202) with inferior vena cava dimension increased by over 5 mm on admission.

CONCLUSIONS

Inferior vena cava dimension in patients with heart failure is correlated with the tricuspid regurgitation grade in the stable state and at acute exacerbation. The increase in inferior vena cava dimension between stable and exacerbated states, but not the actual value, is clinically useful to evaluate patients with acute exacerbation of chronic heart failure.

Long-term follow-up of atrial contraction after the maze procedure in patients with mitral valve disease

OBJECTIVES

We sought to determine the effectiveness of the maze procedure for maintaining sinus rhythm and atrial contraction for a long period in patients with mitral valve disease.

BACKGROUND

Although the maze procedure for atrial fibrillation (AF) has been effective in restoring sinus rhythm in patients with mitral valve disease, the long-term results of this procedure have not been determined.

METHODS

We echocardiographically studied 94 consecutive patients with mitral valve disease before, as well as early (3.1 +/- 3.3 months) and late (2.2 +/- 0.9 years) after, the maze procedure. Peak velocity and the time-velocity integral of the left ventricular (LV) diastolic filling wave during atrial contraction (A wave), as well as the atrial filling fraction (calculated as the ratio of the time-velocity integral of the A wave to total diastolic filling), were obtained from transmitral flow recordings. Peak A wave velocity > or =10 cm/s was considered to indicate echocardiographic evidence of effective atrial contraction.

RESULTS

Regular rhythm with P waves was restored in 70 patients (74%) in the early stage and in 59 patients (63%, p = 0.09) in the late stage after the maze procedure. Forty-seven patients (50%) in the early stage and 36 patients (38%, p = 0.14) in the late stage showed effective atrial contraction by Doppler echocardiography. Left atrial (LA) and LV end-diastolic diameters significantly decreased after the procedure (from 59 +/- 13 to 48 +/- 7 mm, p < 0.01; and from 54 +/- 9 to 47 +/- 5 mm, p < 0.01, respectively) and did not show significant changes during the follow-up period. Once atrial contraction was resumed, its degree did not change between the early and late stages after the maze procedure (17 +/- 6% vs. 17 +/- 6% for atrial filling fraction).

CONCLUSIONS

Sinus rhythm and atrial contraction recovered early after the maze procedure in most patients and were maintained for more than two years. Once active atrial contraction was resumed, the degree of contraction did not change thereafter. These results demonstrate that the maze procedure is effective for a long period in patients with mitral valve disease.

A new model-based method of reconstructing central aortic pressure from peripheral arterial pressure

We have shown in our previous study that the transfer function between central aortic pressure and tonometric radial arterial pressure can be modeled as a pure elastic lossless tube terminated with a modified Windkessel. We hypothesized, using the model-derived radial arterial flow, that central pressure could be reconstructed by adding the time-shifted forward and backward pressure components (Stergiopulos et al.: Am J Physiol 274: H1386---H1392, 1998). In eight patients (age 16--75), central micromanometric and radial arterial tonometric pressure were measured simultaneously. We imposed measured tonometric pressure to the terminal modified Windkessel to estimate radial arterial flow, with which tonometric pressure was separated into forward and backward components. These components were then appropriately time shifted, and summed to central pressure. We used average parameter values for the terminal impedance, but individualized the transmission delay. The poor correlation (r(2)) between tonometric and central pressure (0.264--0.765) was improved by both central pressure reconstruction methods (generalized transfer function: 0.887--0.974, model-based method: 0.849--0.979). The sensitivity analysis indicated that the key model parameter in reconstructing central pressure was the transmission delay. We conclude that our model-based method was capable of reconstructing central pressure as precisely as the generalized transfer function method, and also capable of individualizing the transfer function by changing the transmission delay.

The stereoselective effects of bucolome on the pharmacokinetics and pharmacodynamics of racemic warfarin

The objective of this study was to investigate the stereoselective influence of bucolome on the pharmacokinetics and pharmacodynamics of warfarin in Japanese inpatients with heart disease. Thirty patients were administered a fixed-maintenance dose of warfarin alone once a day for at least 7 days. The other 25 patients were concomitantly administered warfarin and a 300 mg dose of bucolome once a day, and blood samples were collected on days 1, 4, 7, 14, or 21 after administration of bucolome. Serum concentration of warfarin enantiomers was measured by a chiral reversed-phase HPLC-ultraviolet detection method. The PT-INR was used as a measure of the pharmacodynamic effect of warfarin. Coadministration of bucolome and warfarin had no effect on serum (R)-warfarin concentration and significantly increased serum (S)-warfarin concentration compared with warfarin alone. The PT-INR of warfarin alone was significantly lower with bucolome cotreatment. These results indicate that the augmented anticoagulant effect of warfarin by bucolome is due to inhibition of (S)-warfarin metabolism in vivo. When bucolome is added to a stabilized regimen of warfarin therapy, the dose of warfarin should be reduced by about 30% to 60%, and caution should be exercised during the first 7 days after coadministration of bucolome.

Complementary roles of pro-gastrin-releasing peptide (ProGRP) and neuron specific enolase (NSE) in diagnosis and prognosis of small-cell lung cancer (SCLC)

In this study, we evaluated the clinical usefulness of ProGRP and NSE for diagnosis and prognosis of small-cell lung cancer (SCLC). Serum levels of ProGRP and NSE were determined in 108 healthy subjects, 103 patients with benign pulmonary diseases, 142 with non-small cell lung cancer (NSCLC), and 114 with SCLC. Sensitivity of ProGRP in diagnosis of SCLC was significantly higher than that of NSE (64.9 vs. 43.0%, P < 0.001). The difference was substantial in patients with limited disease (56.5 vs. 20.3%, P < 0.001). However, 11 of 40 SCLC patients with normal levels of serum ProGRP (27.5%) showed elevated levels of serum NSE. In the SCLC patients receiving chemotherapy, the CR rate in patients with elevated NSE levels was significantly lower than in patients with normal levels of NSE (18.5 vs. 61.7%, P < 0.001). Elevation of both ProGRP and NSE was a poor prognostic factor, and patients with elevated levels of either ProGRP or NSE showed shorter survival than those without. From multivariate analysis, NSE was found to have a greater effect on survival of SCLC patients than ProGRP. These findings indicate that ProGRP is more sensitive than NSE for diagnosis of SCLC, while NSE is superior to ProGRP as a prognostic factor. In conclusion, both ProGRP and NSE are useful tumor markers and they have a complementary role for each other in diagnosis and prognosis of SCLC.

Short-term oral administration of L-arginine improves hemodynamics and exercise capacity in patients with precapillary pulmonary hypertension

We sought to assess the effects of oral supplementation of L-arginine, the precursor of nitric oxide (NO), on hemodynamics and exercise capacity in patients with pulmonary hypertension. Acute hemodynamic responses to oral L-arginine (0.5 g/10 kg body weight) or placebo were examined in 19 patients with primary or precapillary secondary pulmonary hypertension. Cardiopulmonary exercise tests were performed to measure peak oxygen consumption (peak V O(2)) and the ventilatory response to carbon dioxide production (V E-V CO(2) slope) before and 1 wk after treatment with L-arginine (1.5 g/10 kg body weight/d) or placebo. Oral supplementation of L-arginine significantly increased plasma L-citrulline, which indicated enhancement of NO production. Supplemental L-arginine produced a 9% decrease in mean pulmonary arterial pressure (53 +/- 4 to 48 +/- 4 mm Hg, p < 0.05) and a 16% decrease in pulmonary vascular resistance (14.8 +/- 1.5 to 12.4 +/- 1.4 Wood units, p < 0.05). L-arginine modestly decreased mean systemic arterial pressure (92 +/- 4 to 87 +/- 3 mm Hg, p < 0.05). A 1-wk supplementation of L-arginine resulted in a slight increase in peak V O(2) (831 +/- 88 to 896 +/- 92 ml/min, p < 0.05) and a significant decrease in the V E- V CO(2) slope (43 +/- 4 to 37 +/- 3, p < 0.05) without significant systemic hypotension. Hemodynamics and exercise capacity remained unchanged during placebo administration. These results suggest that oral supplementation of L-arginine may have beneficial effects on hemodynamics and exercise capacity in patients with precapillary pulmonary hypertension.

Usefulness of the subendocardial myocardial velocity gradient in low-dose dobutamine stress echocardiography

The subendocardial side of myocardium makes a major contribution to left ventricular (LV) contraction and is very susceptible to ischemia. In this study we sought to quantify regional wall motion during low-dose dobutamine stress echocardiography (DSE) by using the myocardial velocity gradient (MVG) derived from tissue Doppler imaging (TDI). We then compared the usefulness of subendocardial MVG with that of transmural MVG in detecting subtle wall motion abnormalities. Fourteen patients (single vessel disease = 6; normal coronary arteries = 8) underwent low-dose DSE (10 microg/ kg per min). M-Mode TDI of the LV posterior wall was recorded using a Toshiba SSA-380A combined with custom computer software, and analyzed for both subendocardial and transmural MVG. Visual estimation and transmural MVG failed to clearly demonstrate the differing responses between the nonischemic (systole: 3.0 +/- 0.8/s to 4.9 +/- 1.9/s, not significant; diastole: -4.3 +/- 1.3/s to -5.7 +/- 1.4/s, not significant; mean +/- SD, P versus ischemic segments) and ischemic (systole: 3.3 +/- 1.2/s to 3.8 +/- 1.0/s; diastole: -5.4 +/- 2.0/s to -5.3 +/- 1.1/s) segments during low-dose DSE. Subendocardial MVG demonstrated a significant change in the nonischemic segments (systole: 4.1 +/- 1.0/s to 7.7 +/- 2.2/s, P = 0.012; diastole: -6.5 +/-1.8/s to -11.3 +/- 2.2/s, P = 0.001), whereas the response remained unchanged in the ischemic segments (systole: 4.6 +/-2.4/s to 4.8 +/- 1.2/s; diastole: -7.0 +/- 1.9/s to -7.3 +/- 1.1/s). Subendocardial MVG, particularly diastolic subendocardial MVG, may serve as a useful indicator of subtle ischemic changes in wall motion induced by low-dose DSE.

[Plasma brain natriuretic peptide as a prognostic indicator in patients with primary pulmonary hypertension]

BACKGROUND

Plasma brain natriuretic peptide (BNP) level increases in proportion to the degree of right ventricular dysfunction in pulmonary hypertension. We sought to assess the prognostic significance of plasma BNP in patients with primary pulmonary hypertension.

METHODS AND RESULTS

Plasma BNP was measured in 60 patients with primary pulmonary hypertension at diagnostic catheterization, together with atrial natriuretic peptide, norepinephrine, and epinephrine. Measurements were repeated in 53 patients after a mean follow-up period of 3 months. Forty-nine of the patients received intravenous or oral prostacyclin. During a mean follow-up period of 24 months, 18 patients died of cardiopulmonary causes. According to multivariate analysis, baseline plasma BNP was an independent predictor of mortality. Patients with a supramedian level of baseline BNP (> or = 150 pg/ml) had a significantly lower survival rate than those with an inframedian level, according to Kaplan-Meier survival curves (p < 0.05). Plasma BNP in survivors decreased significantly during the follow-up (217 +/- 38 to 149 +/- 30 pg/ml, p < 0.05), whereas that in nonsurvivors increased (365 +/- 77 to 544 +/- 68 pg/ml, p < 0.05). Thus, survival was strikingly worse for patients with a supramedian value of follow-up BNP (> or = 180 pg/ml) than for those with an inframedian value (p < 0.0001).

CONCLUSIONS

A high level of plasma BNP, and in particular, a further increase in plasma BNP during follow-up, may have a strong, independent association with increased mortality in patients with primary pulmonary hypertension.