Association between preoperative phase angle and all-cause mortality after cardiovascular surgery: A retrospective cohort study.

BACKGROUND: The importance of preoperative physical function assessment for post-operative intervention has been reported in older patients undergoing cardiovascular surgery. Phase angle (PhA), measured using bioelectrical impedance analysis, is an indicator of cellular health and integrity and is reported as a prognostic factor in several chronic diseases; however, its association with the long-term prognosis of cardiovascular surgery remains unclear. This study aimed to investigate the prognostic value of PhA for long-term mortality in patients undergoing cardiovascular surgery. METHODS: This retrospective cohort study included consecutive patients who underwent elective cardiovascular surgery between October 2016 and March 2021 at Nagoya Heart Center, Japan. PhA was assessed using bioelectrical impedance analysis before surgery, and physical function measures (gait speed, grip strength and short physical performance battery [SPPB]) were measured synchronously. The association between PhA and all-cause mortality after discharge was assessed using Kaplan-Meier and multivariate Cox regression analyses. The incremental prognostic value of PhA was compared with other physical function measures using net reclassification improvement (NRI) and integrated discrimination improvement (IDI). RESULTS: A total of 858 patients were included in the present analysis (mean age = 68.4 ± 11.9 years, 67.6% male). PhA positively correlated with body mass index (ρ = 0.38, P < 0.001), skeletal muscle mass index (ρ = 0.58, P < 0.001), usual gait speed (ρ = 0.44, P < 0.001), grip strength (ρ = 0.73, P < 0.001) and SPPB (ρ = 0.51, P < 0.001). The mean follow-up period, within which 44 (4.7%) died, was 908.9 ± 499.9 days for the entire cohort. Kaplan-Meier survival curves based on the PhA tertiles showed that higher PhA was associated with better survival (log-rank test, P < 0.001). The Cox regression analysis showed the independent association of PhA with mortality risk (hazard ratio: 0.91 per 0.1° increment; 95% confidence interval [CI]: 0.87-0.95; P < 0.001). The NRI and IDI showed significant improvements in predicting mortality after adding PhA to the clinical model consisting of age, sex and cardiac and renal function (NRI: 0.426, 95% CI: 0.124-0.729, P = 0.006; IDI: 0.037, 95% CI: 0.012-0.062, P = 0.003). The predictive model consisting of the clinical model and PhA was superior to the model consisting of the clinical model and each of the other physical function indicators (P < 0.05). CONCLUSIONS: PhA correlated with physical function and independently predicted long-term mortality after cardiovascular surgery. The additive prognostic value of PhA compared with the other physical function measures suggests the clinical usefulness of preoperative PhA for risk stratification in planning post-operative treatment and rehabilitation.

Factors Associated With Changes in Objectively Measured Moderate to Vigorous Physical Activity in Patients After Percutaneous Coronary Intervention: A Prospective Cohort Study.

BACKGROUND: This study aimed to clarify factors affecting changes in moderate to vigorous physical activity (MVPA) in patients 1 to 3 months after undergoing percutaneous coronary intervention (PCI). METHODS: In this prospective cohort study, we enrolled patients aged <75 years who underwent PCI. MVPA was objectively measured using an accelerometer at 1 and 3 months after hospital discharge. Factors associated with increased MVPA (≥150 min/wk at 3 mo) were analyzed in participants with MVPA < 150 minutes per week at 1 month. Univariate and multivariate logistic regression analyses were performed to explore variables potentially associated with increasing MVPA, using MVPA ≥ 150 minutes per week at 3 months as the dependent variable. Factors associated with decreased MVPA (<150 min/wk at 3 mo) were also analyzed in participants with MVPA ≥ 150 minutes per week at 1 month. Logistic regression analysis was performed to explore factors of declining MVPA, using MVPA < 150 minutes per week at 3 months as the dependent variable. RESULTS: We analyzed 577 patients (median age 64 y, 13.5% female, and 20.6% acute coronary syndrome). Increased MVPA was significantly associated with participation in outpatient cardiac rehabilitation (odds ratio 3.67; 95% confidence interval, 1.22-11.0), left main trunk stenosis (13.0; 2.49-68.2), diabetes mellitus (0.42; 0.22-0.81), and hemoglobin (1.47, per 1 SD; 1.09-1.97). Decreased MVPA was significantly associated with depression (0.31; 0.14-0.74) and Self-Efficacy for Walking (0.92, per 1 point; 0.86-0.98). CONCLUSIONS: Identifying patient factors associated with changes in MVPA may provide insight into behavioral changes and help with individualized PA promotion.

The Detectability of Iterative CT Reconstruction for Low-contrast Lesions in Hyperacute Cerebral Infarction: Assessment with Newly Developed Dedicated Head Phantoms.

Iterative reconstruction techniques, such as adaptive statistical iterative reconstruction (ASiR), improve the contrast-to-noise ratio of computed tomography (CT) images; however, underlying anatomical structures may nevertheless hamper detectability of low-contrast areas in clinical situations, despite using such a technique. We therefore conducted a phantom study to investigate the efficacy of ASiR in improving the detectability of low-contrast areas in the presence of brain anatomical structures. We developed dedicated head phantoms simulating hyperacute cerebral infarction and confirmed that their CT numbers were sufficiently reproducible and that observer performance in detecting low-contrast areas using these phantoms more closely resembled that in clinical situations than that using a simple phantom. The efficacy of ASiR in improving low-contrast detectability was evaluated via receiver operating characteristics analysis. The mean area under the curve (AUC) values at ASiR blend rates of 0%, 30%, 60%, and 100% were 0.57, 0.57, 0.59, and 0.59 at 200 mA; 0.83, 0.84, 0.84, and 0.90 at 500 mA; and 0.79, 0.77, 0.76, and 0.79 at 800 mA, respectively. No significant differences were noted in AUC values among ASiR blend rates at any mA setting, suggesting that ASiR does not improve the detectability of subtle low-contrast lesions seen in hyperacute cerebral infarction in clinical situations.

Feasibility and accuracy of relative electron density determined by virtual monochromatic CT value subtraction at two different energies using the gemstone spectral imaging.

BACKGROUND: Recent work by Saito (2012) has demonstrated a simple conversion from energy-subtracted computed tomography (CT) values (ΔHU) obtained using dual-energy CT to relative electron density (RED) via a single linear relationship. The purpose of this study was to investigate the feasibility of this method to obtain RED from virtual monochromatic CT images obtained by the gemstone spectral imaging (GSI) mode with fast-kVp switching. METHODS: A tissue characterization phantom with 13 inserts made of different materials was scanned using the GSI mode on a Discovery CT750 HD. Four sets of virtual monochromatic CT images (60, 77, 100 and 140 keV) were obtained from a single GSI acquisition. When we define Δ HU in terms of the weighting factor for the subtraction α, Δ HU ≡ (1 + α)H - αL (H and L represent the CT values for high and low energy respectively), the relationship between Δ HU and RED is approximated as a linear function, a × Δ HU/1000 + b (a, b = unity). We evaluated the agreement between the determined and nominal RED. We also have investigated reproducibility over short and long time periods. RESULTS: For the 13 insert materials, the RED determined by monochromatic CT images agreed with the nominal values within 1.1% and the coefficient of determination for this calculation formula was greater than 0.999. The observed reproducibility (1 standard deviation) of calculation error was within 0.5% for all materials. CONCLUSIONS: These findings indicate that virtual monochromatic CT scans at two different energies using GSI mode can provide an accurate method for estimating RED.

High-resolution inventory of Japanese anthropogenic mercury emissions.

Heavy metals like mercury that are emitted into the environment remain there indefinitely, posing a long-term threat to both the environment and human health. Elemental mercury is volatile and is in gaseous form, and because of the long residence time, transported over long distances. Comprehensive control of mercury emissions therefore remains an important international issue. The crucial steps for designing effective approaches for such control include the quantification of mercury emissions by sources and the identification of geographical characteristics of the emissions. In this study a detailed, high-resolution inventory of Japanese mercury emissions in 2005 was developed to improve understanding of their geographical distribution. Proceeding from a national emissions inventory per source category, emissions were spatially allocated with increasing geographical resolution in a stepwise procedure using statistics from geographic information resources, yielding mercury emissions per prefecture, per municipality and per grid cell of approximately 1 × 1 km. The five prefectures with the highest emissions were Fukuoka, Yamaguchi, Hyogo, Oita, and Hokkaido, accounting for 35.2% of all emissions. In each prefecture a small number of municipalities account for a major share of emissions. Distribution by grid cell is characterized by a concentration of 50% of all emissions in a mere 32 of the 255 954 grid cells over which emissions are distributed in this study. It was also quantitatively confirmed that use of larger grid cells leads to greater uncertainty in emissions distribution. Problems with data collection are clarified and measures to improve the accuracy of future estimation are proposed.

[Noninvasive assessment of coronary artery with substantial contrast volume reduction using 320-detector row computed tomography: a feasibility study].

The recently introduced 320-detector row computed tomography (320-row CT) allows very fast volumetric acquisition of the entire heart. Because the total amount of contrast agent required for CT coronary angiography (CTCA) depends directly on the acquisition time, 320-row CTCA would substantially reduce the contrast agent dose. The objective of this retrospective study was to evaluate the feasibility of contrast volume reduction on 320-row CTCA compared with 64-detector row CTCA (64-row CTCA). We retrospectively reviewed consecutive 320- and 64-row CTCA data (16 eligible cases for each; administrated contrast volume, 20-24 ml for the former and 50-65 ml for latter) from a homogeneous patient population (age ≤ 81, body weight ≤ 67 kg, and heart rate ≤ 69 bpm). The two types of CTCA data were compared with respect to the successful rate of adequate intravascular contrast enhancement defined as the number of segments with attenuations of more than 250 HU divided by total number of coronary segments evaluated. Our dataset provided mean intravascular attenuation values of 320 and 404 HU on the 320- and 64-row CTCA, respectively. Although the attenuation values were statistically lower for the 320-row CTCA (P < 0.001), there was no significant difference in the successful rates of adequate intravascular contrast enhancement (rate of 0.98 for each; P > 0.05). We therefore conclude that 320-row CTCA is a feasible method of diagnostic imaging and is superior to 64-row CTCA because it uses less of the contrast medium.

Synthesis and characterization of cell-adhesive silk-like proteins constructed from the sequences of Anaphe silk fibroin and fibronectin.

New silk-like recombinant proteins, [(AAG)(6)ASTGRGDSPAAS](n) and [(AG)(9)ASTGRGDSPAAS](n), with high cell adhesive activities were designed and produced from E. coli. These are recombinant proteins with characteristic sequences from the silk fibroin of a wild silkworm, Anaphe , and the cell adhesive region, including the sequence RGD derived from fibronectin. They showed higher cell adhesion activity than the parent protein, Anaphe silk fibroin without the RGD sequence. In addition, the activities were very similar to that of collagen, which acted as a positive control. Thus, it is demonstrated that the primary structure of Anaphe silk fibroin, which is composed largely of alanine and glycine residues, can be used as a platform for the basic structures of silk-like cell adhesive proteins. The structural characterization of the silk-like recombinant proteins was performed with (13)C CP/MAS NMR.

Pulsed NMR study of the curing process of epoxy resin.

To analyze a curing process of epoxy resin in terms of molecular motion, we adapted a pulsed NMR method. Three kinds of (1)H spin-spin relaxation times (T(2L) (long), T(2S) (short) and T(2M) (intermediate)) were estimated from observed solid echo train signals as the curing process proceeded. A short T(2S) value below 20 micros suggests the existence of a motion-restricted chain, that is, cured elements of resin, and its fraction, P(S), sigmoidally increased with the curing time. On the other hand, the fraction of T(2L), P(L), decreased with the reaction time reciprocally against P(S), suggesting the disappearance of highly mobile molecules raised from pre-cured resin. The spin-lattice relaxation time, T(1), was also measured to check another aspect of molecular motion in the process. T(1) of the mixed epoxy resin and curing agent gradually increased just after mixing both of them. This corresponds to an increment of a less-mobile fraction, of which the correction time is more than 10(-6) s, and also means that the occurrence of a network structure whose mobility is strongly restricted by chemically bonded bridges between the epoxy resin and curing agent. The time courses of these parameters coincided with those of IR peaks pertinent to the curing reaction. Therefore, pulsed NMR is a useful tool to monitor the hardening process of epoxy resin in real time non-distractively in terms of the molecular motion of protons.

Silklike materials constructed from sequences of Bombyx mori silk fibroin, fibronectin, and elastin.

Two silklike proteins, [TGRGDSPAGG(GAGAGS)3AS]5 (FS5) and [TGRGDSPA-(GVPGV)2GG(GAGAGS)3AS]8 (FES8) were designed to demonstrate the superior performance as biomaterials of silklike proteins. The former protein consists of the crystalline domain sequence, (GAGAGS)n from Bombyx mori silk fibroin and cell-adhesive sequence TGRGDSPA coming from fibronectin-containing RGD triplet. The additional sequence (GVPGV)n from elastin was included in the latter protein. The considerably higher cell-adhesion activities of these proteins for NHDF and VERO cells were observed by comparing with those of silklike materials without RGD sequences and also the crystalline fraction of B. mori silk fibroin. This tendency was independent of the treatments, 4.5M LiClO4 or formic acid (FA), on silklike proteins. Their activities are also higher than those of commercial Fibronectin F for NHDF cell. Their structural characterization was studied using 13C solid-state NMR. Although the overlapped peaks in usual 13C CP/MAS NMR spectra make the detailed structural analysis difficult, the methyl resonance regions observed using dipolar dephasing NMR were very useful for the analysis. The presence of both random coil and beta-sheet structures was observed in these proteins clearly. The content of beta-sheet structure in both proteins increases after FA treatment when compared with the lyophilized samples. The production of electrospun nanofibers from their hexafluoroacetone solution was also tried. The silklike protein FES8 could prepare nonwoven silk fibers although FS5 could not.

Value of cine MRI for better visualization of the proximal small bowel in normal individuals.

While enteroclysis seems to be the most efficacious method in achieving bowel distension, enterographic methods have become widespread due to the unpleasantness of enteroclysis and the radiation involved with positioning the catheter. Cine images in MRI can be done without radiation. Our aim is to see if and how cine MR imaging can improve visualization of bowel loops by capturing them while distended. Ten healthy individuals were asked to drink up to 2,000 ml of an oral solution made locally over a 60-min period. Then they underwent MRI using coronal balanced fast field echo (b-FFE) covering small bowel loops. If the initial exam revealed collapsed bowel loops an additional 50 mg of erythromycine was given intravenously with the subject still in the scanner and then cine imaging was performed. The degree of distension of different segments of the small bowel was measured before and after cine imaging and compared. The distension score was significantly higher after addition of the cine images as well, being only significant for depiction of the duodenum and jejunum. Our preliminary study suggests that cine MRI can give better image depiction of the proximal small bowel in healthy volunteers, perhaps circumventing the need for enteroclysis in some cases. There is a need for validation of these results in patients with small bowel disease.

Effects of magnesium sulfate on neuromuscular function and spontaneous breathing during sevoflurane and spinal anesthesia.

The purpose of the present study was to determine the effects of magnesium sulfate (MgSO(4)) on the neuromuscular function and spontaneous breathing of patients under sevoflurane and spinal anesthesia. Twenty-two patients with a history of arrhythmia undergoing elective knee surgery were randomly assigned to two groups: group M (n = 11), administered with MgSO(4) 40 mg.kg(-1), and group S (n = 11), administered with saline. A combination of spinal anesthesia with 2% sevoflurane inhalation was applied to all patients under spontaneous breathing. Tidal volume (VT: ), respiratory rate (RR) and end-tidal carbon dioxide (ET(CO) (2)) were measured before the MgSO(4) or saline injection and measurements were repeated at 5, 15, 30, and 45 min after the injection. Neuromuscular function was continuously monitored with an acceleromyograph to record the acceleration of the adductor pollicis by stimulating the ulnar nerve at a frequency of 0.1 Hz. The VT: , RR, and ET(CO) (2) showed little change in either group, and there was no significant difference between, the groups. The single-twitch response showed significant differences between the two groups (P = 0.0006). The present study indicated that the MgSO(4) had a minimal effect on spontaneous breathing in patients undergoing sevoflurane and spinal anaesthesia, but that it attenuated the safety margin of neuromuscular function.

Stereoscopic scintigraphic imaging of breast cancer sentinel lymph nodes.

BACKGROUND: Lymphoscintigraphy is used preoperatively to identify sentinel lymph nodes (SLNs). Conventional planar scintigraphy cannot provide three-dimensional(3D) information for SLN biopsy. We applied stereoscopic imaging to preoperative lymphoscintigraphy to obtain 3D information and evaluated its usefulness. METHODS: Forty-four clinical stage I breast cancer patients (1 male, 43 females; age, 59.4+/-11.4 years) were enrolled in this study. Three hours after the injection of Tc-99m, 10 degrees of oblique images and routine anterior and lateral images were acquired. Anterior and lateral stereoscopic images were obtained in all studies, except for 2 patients; only lateral views were done for those. Two experienced radiologists enumerated the visualized hot nodes. RESULTS: Stereoscopic imaging delineated more hot axillary lymph nodes compared to routine planar imaging in 8 of 42 patients (19.0%) on anterior view, 5 of 44 patients (11.4%) on lateral view, and 11 of 44 patients (25.0%) on either the anterior or lateral view. Statistically significant differences were observed between stereoscopic and routine planar imaging method on the anterior (p=0.012) and the lateral views (p=0.043). The stereoscopic imaging provided 3D information and effectively separated closely located hot nodes that were viewed as one hot node on conventional planar images. Thirty-eight out of 42 cases (90%) with anterior stereoscopic images identified the same number or more axillary hot nodes compared with lateral stereoscopic images. CONCLUSION: The stereoscopic imaging method could improve the preoperative identification of SLNs. This method is technically simple, and could be a powerful diagnostic tool for SLN imaging breast cancer.

Value of CT thallium-201 SPECT fusion imaging over SPECT alone for detection and localization of nasopharyngeal and maxillary cancers.

OBJECTIVE: The purpose of this study was to investigate the incremental clinical utility of CT and high-resolution SPECT fusion imaging. MATERIALS AND METHODS: Eighteen patients with nasopharyngeal cancer or cancers around the maxilla were scanned with high-resolution SPECT at the time of initial diagnosis (18 studies) and during follow-up after chemoradiotherapy (23 studies). SPECT results were compared with histologic findings or the findings of other imaging techniques. In addition, automatic image registration without fiducial markers was performed from CT and SPECT data, and the effect of fusion imaging on the localization of abnormalities was evaluated. RESULTS: All of the original 18 untreated lesions showed high uptake. Recurrent tumors had a tendency to show high uptake (seven of nine patients), whereas little or no uptake generally represented no recurrence (12 of 14 patients) (chi-square test with Yates correction: chi2 = 6.80, p < 0.01). In two patients, physiologic uptake in the unilateral prevertebral muscle was revealed on image fusion. In four of the nine recurrent nasopharyngeal cancers (44%), SPECT alone could not determine abnormalities in uptake sites, whereas CT/SPECT fusion imaging clearly localized the sites and was helpful for treatment strategy. CONCLUSION: High-resolution thallium-201 (201Tl) SPECT has a very high detection rate in patients with nasopharyngeal cancer and cancers around the maxilla. However, the anatomic identification or localization of the uptake sites is sometimes difficult without CT/SPECT fusion imaging. This technique without external markers is practically feasible to generate clinically valid fusion images.

Feast/famine regulatory proteins (FFRPs): Escherichia coli Lrp, AsnC and related archaeal transcription factors.

Feast/famine regulatory proteins comprise a diverse family of transcription factors, which have been referred to in various individual identifications, including Escherichia coli leucine-responsive regulatory protein and asparagine synthase C gene product. A full length feast/famine regulatory protein consists of the N-terminal DNA-binding domain and the C-domain, which is involved in dimerization and further assembly, thereby producing, for example, a disc or a chromatin-like cylinder. Various ligands of the size of amino acids bind at the interface between feast/famine regulatory protein dimers, thereby altering their assembly forms. Also, the combination of feast/famine regulatory protein subunits forming the same assembly is altered. In this way, a small number of feast/famine regulatory proteins are able to regulate a large number of genes in response to various environmental changes. Because feast/famine regulatory proteins are shared by archaea and eubacteria, the genome-wide regulation by feast/famine regulatory proteins is traceable back to their common ancestor, being the prototype of highly differentiated transcription regulatory mechanisms found in organisms nowadays.

Effect of thrombin on permeability of human epithelial cell monolayers.

Epithelial cells play an important role in maintaining the airway barrier, which is impaired in inflammatory conditions. Recently, thrombin was reported to be increased in the airway of patients with asthma, and thrombin has been shown to increase the permeability of endothelial cell monolayers. Therefore, we suspected that thrombin affects airway permeability. Calu-3 cell monolayers were established on microporous membranes of tissue culture cell inserts. We examined the effects of topically applied thrombin or thrombin receptor-activating peptide (TRAP) on: (1) transepithelial permeability (luminal to serosal transfer) of radiolabeled mannitol and albumin, (2) changes in electrical resistance, and (3) actin fiber content as assessed by fluorescence microscopy. Compared with untreated control cultures, treatment of the monolayers for 24 h with thrombin or TRAP significantly decreased the electrical resistance and increased the permeability to mannitol and albumin. In addition, these treatments enhanced the appearance of actin stress fibers, and small gaps became visible at areas of cell-cell contact. Thrombin appears to increase epithelial permeability by receptor-mediated reorganization of the actin network in airway epithelial cells. This is likely to contribute to the impairment of the airway barrier function.

Bacteriological survey of feces from feral pigeons in Japan.

Some public areas in Japan such as parks and gardens can be highly contaminated with pigeon feces. We examined levels of four bacterial contaminations in fecal samples from feral pigeons in 7 prefectures. We isolated Salmonella Typhimurium and S. Cerro from 17 (3.9%) of 436 samples, as well as Mycobacterium spp. including M. avium-intracellulare complex from 29 (19.0%) of 153 samples. The polymerase chain reaction detected Chlamydia psittaci and C. pecorum in 106 (22.9%) of 463 samples, but E. coli O-157 was not isolated from any of the samples. Our results indicate that pigeon feces are a source of several zoonotic agents for birds, animals and humans.

Transgenic mice expressing mutant (N279K) human tau show mutation dependent cognitive deficits without neurofibrillary tangle formation.

Mutations in the tau gene, which is located on chromosome 17, were found causative for autosomal dominantly inherited frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17). To determine if cognitive deficits could be caused by tau mutations, two transgenic mouse lines were generated expressing a four-repeat isoform of human tau or its mutant, containing one of the FTDP-17 mutations (WILD mice and N279K mice). In open field test, N279K mice showed hyperactivity in locomotion and rearing. In prepulse inhibition test, N279K mice but not Wild mice showed significant deficits. Both transgenic mice, especially N279K mice, showed impairment in acquisition of spatial learning in Morris water maze. Although both N279K mice and Wild mice acquired passive avoidance as well as non-transgenic mice, N279K mice but not Wild mice showed severe deficits in acquisition of active avoidance. Histological analysis of the present mutant mice did not show any signs of neurofibrillary tangle formations in the brain, and cognitive dysfunction seemed to precede such neuropathological changes or occur independently from them. The behavioral phenotype of N279K mice mimics features of human FTDP-17 and provides a basic model for elucidating mechanisms underlying cognitive deficits in not only FTDP-17, but also diverse tauopathies.

Voxel dimensions required for micromorphologic evaluation of ground-glass opacity on lung high-resolution CT.

PURPOSE: To clarify the appropriate voxel dimensions required for pathologic evaluation of areas with ground-glass opacity on lung high-resolution computed tomography (HRCT). MATERIALS AND METHODS: Synchrotron radiation CT (SRCT) images of autopsied lung speci-mens (n=25) that showed ground-glass opacity on HRCT were reconstructed with 12 different voxel dimensions ranging from 0.006 to 0.6 mm. The specimens were micromorphologically categorized into one of three pathologic groups: alveolar, interstitial, and mixed abnormalities. Each SRCT image was independently diagnosed as one of three pathologic groups by six chest radiologists. The diagnostic accuracy required to estimate the appropriate voxel dimensions was compared among different voxel dimensions by means of the Tukey test. RESULTS: Diagnostic accuracy with voxel dimensions less than or equal to 0.06 mm was significantly higher than that with voxel dimensions of 0.18 mm or more (p<0.01). There was, however, no significance of difference in diagnostic accuracy with voxel dimensions of less than or equal to 0.06 mm. In addition, no significant difference in diagnostic accuracy was found with voxel dimensions of 0.18 mm or more. CONCLUSION: The appropriate voxel dimensions are approximately 0.06 mm for pathologic differentiation of areas with ground-glass opacity on HRCT.