Neovascularization of ischemic myocardium by human bone-marrow-derived angioblasts prevents cardiomyocyte apoptosis, reduces remodeling and improves cardiac function.

Left ventricular remodeling is a major cause of progressive heart failure and death after myocardial infarction. Although neoangiogenesis within the infarcted tissue is an integral component of the remodeling process, the capillary network is unable to support the greater demands of the hypertrophied myocardium, resulting in progressive loss of viable tissue, infarct extension and fibrous replacement. Here we show that bone marrow from adult humans contains endothelial precursors with phenotypic and functional characteristics of embryonic hemangioblasts, and that these can be used to directly induce new blood vessel formation in the infarct-bed (vasculogenesis) and proliferation of preexisting vasculature (angiogenesis) after experimental myocardial infarction. The neoangiogenesis resulted in decreased apoptosis of hypertrophied myocytes in the peri-infarct region, long-term salvage and survival of viable myocardium, reduction in collagen deposition and sustained improvement in cardiac function. The use of cytokine-mobilized autologous human bone-marrow-derived angioblasts for revascularization of infarcted myocardium (alone or in conjunction with currently used therapies) has the potential to significantly reduce morbidity and mortality associated with left ventricular remodeling.

cAMP pulse during preservation inhibits the late development of cardiac isograft and allograft vasculopathy.

The causes of transplant-associated coronary artery disease remain obscure, and there is no known treatment. Preservation injury of murine heterotopic vascularized cardiac isografts caused a small, albeit significant, increase in neointimal formation; preservation injury of allografts markedly increased both the incidence and severity of transplant-associated coronary artery disease. As cAMP is an important vascular homeostatic mediator the levels of which decline during organ preservation, buttressing cAMP levels solely during initial preservation both improved acute allograft function and reduced the severity of transplant-associated coronary artery disease in grafts examined 2 months later. Inhibiting the cAMP-dependent protein kinase abrogated these beneficial effects. cAMP treatment was associated with an early reduction in leukocyte infiltration and a reciprocal decrease in superoxide and increase in NO levels. These data indicate that alloantigen-independent injury to the graft, which occurs at the time of cardiac preservation, can set in motion pathological vascular events that are manifest months later. Furthermore, a cAMP pulse during cardiac preservation reduces the incidence and severity of transplant-associated coronary artery disease.

Effect of neonatal capsaicin treatment on neural activity in the medullary dorsal horn of neonatal rats evoked by electrical stimulation to the trigeminal afferents: an optical, electrophysiological, and quantitative study.

To elucidate which glutamate receptors, NMDA or non-NMDA, have the main role in synaptic transmission via unmyelinated afferents in the trigeminal subnucleus caudalis (the medullary dorsal horn), and to examine the early functional effects of neonatal capsaicin treatment to the subnucleus caudalis, optical recording, field potential recording, and quantitative study using electron micrographs were employed. A medulla oblongata isolated from a rat 5--7 days old was sectioned horizontally 400-microm thick or parasagittally and stained with a voltage-sensitive dye, RH482 or RH795. Single-pulse stimulation with high intensity to the trigeminal afferents evoked optical responses mainly in the subnucleus caudalis. The optical signals were composed of two phases, a fast component followed by a long-lasting component. The spatiotemporal properties of the optical signals were well correlated to those of the field potentials recorded simultaneously. The fast component was eliminated by 6-cyano-7-nitro-quinoxaline-2,3-dione (CNQX; 10 microM), while the long-lasting component was not. The latter increased in amplitude under a condition of low Mg(2+) but was significantly reduced by DL-2-amino-5-phosphonovaleric acid (AP5; 30 microM). Neonatal capsaicin treatment also reduced the long-lasting component markedly. In addition, the decreases in the ratio of unmyelinated axons to myelinated axons and in the ratio of unmyelinated axons to Schwann cell subunits of trigeminal nerve roots both showed significant differences (P<0.05, Student's t-test) between the control group and the neonatal capsaicin treatment group. This line of evidence indirectly suggests that synaptic transmission via unmyelinated afferents in the subnucleus caudalis is mediated substantially by NMDA glutamate receptors and documented that neonatal capsaicin treatment induced a functional alteration of the neural transmission in the subnucleus caudalis as well as a morphological alteration of primary afferents within several days after the treatment.

Real-time, 3-dimensional echocardiography acquires all standard 2-dimensional images from 2 volume sets: a clinical demonstration in 45 patients.

To test the hypothesis that real-time, 3-dimensional (3-D) echocardiography can obtain all standard 2-dimensional (2-D) views from acquisition of 2 volume sets, we scanned 45 patients (24 men, 21 women; mean age 49 +/- 17 years). This real-time 3-D device (VOLUMETRICS Medical Imaging, Durham, NC) uses a matrix phased array transducer in a 60 degree pyramidal volume. Images are displayed as 2 steerable, intersecting, conventional 2-D image sectors that can be oriented throughout 3-D space. By using this equipment, we were able to obtain 93.3% of standard views from a parasternal volume set and 85.2% of standard views from an apical volume set. The mean scanning time was 91 +/- 19 seconds for the parasternal volume set and 86 +/- 22 seconds for the apical volume set. We conclude that standard 2-D views can be obtained in the majority of patients by using this method. This equipment has the potential to substantially decrease the imaging time compared with the standard 2-D echocardiography.

Noninvasive assessment and necropsy validation of changes in left ventricular mass in ascending aortic banded mice.

Although left ventricular (LV) hypertrophy can be induced by aortic banding, noninvasive assessment of changes in LV mass in mice with a banded ascending aorta by using 2-dimensional (2D) images has not been previously performed. In this study we serially assessed changes in LV mass by 2D echocardiography with a newly available 12-MHz transducer in mice with a banded ascending aorta and validated measurements at necropsy. Estimated by echocardiography, LV mass increased from 74+/- 17 mg before banding to 191.08+/-54 mg at 8 weeks after banding (P <.0001), and excellent correlation was shown with postmortem measurements (r = 0.97). Furthermore, with the use of pulsed Doppler 2-dimensionally guided echocardiography, noninvasive measurement of flow velocities in the ascending aorta before and after the band at the various time points was possible. We propose that 2D echocardiography with a 12-MHz transducer is a powerful tool for serial noninvasive evaluations as an adjunct to the study of cardiac hypertrophy in the murine model.

Assessment of left ventricular function by real-time 3-dimensional echocardiography compared with conventional noninvasive methods.

Quantitative assessment of left ventricular ejection fraction is an essential component of cardiac evaluation. We performed real-time 3-dimensional echocardiography in 56 consecutive patients who underwent multigated radionuclide angiography. Thirteen patients were excluded for the following reasons: 5 for large size of left ventricle required for image acquisition, 5 for suboptimal image quality in real-time 3-dimensional echocardiography, and 3 for atrial fibrillation. Finally, we compared left ventricular ejection fraction assessed by real-time 3-dimensional echocardiography and conventional 2-dimensional echocardiography with that obtained by multigated radionuclide angiography in 43 patients. Left ventricular ejection fraction was determined by real-time 3-dimensional echocardiography with the use of parallel plane-disks and sector plane-disks summation methods. A good correlation was obtained between both real-time 3-dimensional echocardiography methods and multigated radionuclide angiography (r = 0.87 and 0.90, standard error of estimate = 3.7% and 4.2%), whereas the relation between the 2-dimensional echocardiography method and radionuclide angiography demonstrated a significant departure from the line of identity (P <.001). In addition, interobserver variability was significantly lower (P <.05) for the real-time 3-dimensional echocardiography methods than that by the 2-dimensional echocardiography method. Real-time 3-dimensional echocardiography may be used for quantification of left ventricular function as an alternative to conventional methods in patients with adequate image quality.

Feasibility of real-time 3-dimensional treadmill stress echocardiography.

Rapid acquisition of echocardiographic images is critical for the predictive accuracy of stress echocardiography. Real-time 3-dimensional echocardiography (RT3D) allows review of several standard 2-dimensional images from a single volumetric data set. To assess the feasibility of RT3D for treadmill stress echocardiography, we performed treadmill stress RT3D on 20 volunteers (10 men and 10 women; mean age 32 +/- 6 years) with a device that uses a matrix phased-array transducer in a 60-degree pyramidal volume. Images are displayed as 2 steerable, intersecting B-scan sectors with adjustable C-scan planes parallel to the transducer face. At pre-exercise and immediate postexercise assessment, the volumetric data were obtained from apical and parasternal windows, respectively. Left ventricular segments were divided into 16 standard segments according to criteria defined by the American Society of Echocardiography. The use of both volume sets resulted in visualization of 98% of the segments at peak exercise. Even with only an apical volume set, 89% of the segments were adequately visualized. Image optimization and acquisition time at peak exercise was 35 +/- 18 seconds from the apical window and 50 +/- 28 seconds from the parasternal window. This preliminary study indicates that RT3D treadmill stress echocardiography is feasible and may be an important application of this new 3-dimensional device.

Intracrystalline structure of enamel crystals affected by caries.

Enamel crystals in the demineralized zones in early caries lesions of human teeth were observed by high-resolution electron microscopy. The enamel crystals frequently exhibited perforations in their centers and defects of various sizes on their lateral surfaces. There were a number of small electron-lucent spots, suggesting that the dissolution of crystals had taken place there. These spots were in especially large numbers near the central dark line. The central perforations, the lateral defects, and the small spots had a common habit which formed regularly along the crystalline a- and b-axes. In many cases, when the central dark line was seen, the perforations were located a few unit cells away from the line. The perforations seem to result from a fusion of small spots, which enlarge by involving other small spots. The lateral defect seemed to enlarge by removal of unit cells and progression along the a- and b-axes. In the regions where the small spots were present, however, the enlargement of the defects also progressed involving the spots. The central dark line seems to be rather resistant to dissolution. One of the main factors for the central perforation of the crystals is thought to be the presence there of especially large numbers of defective sites.

Ultrastructural changes of secreting rat-incisor ameloblasts following administration of vincristine and vinblastine.

Ultrastructural changes of secreting rat-incisor ameloblasts after administration of vincristine and vinblastine were observed. Polarity of nuclei and cytoplasmic organellae was remarkably disturbed; consequently, the regular secreting orientation of cellular products was altered greatly, leading to heterotopic deposition of large amounts of enamel matrix.

Ultrastructural changes in the cementoblasts of rat molars after injection of vincristine.

Cytological changes in the cementoblasts of rats treated with vincristine were investigated. Accumulation of secretion granules indicated a disturbed secretory mechanism in the cells. Conspicuous dilation of the endoplasmic reticulum suggested disturbance in the transport of substances from the rough endoplasmic reticulum to the Golgi elements. These disturbances were interpreted to be a result of disruption of microtubules.

Evidence for uptake of basement membrane by differentiating ameloblasts in the rat incisor enamel organ.

Demonstration of type-IV collagen and acid phosphatase (ACPase) was carried out in the rat incisor enamel organ after the animals were fixed by perfusion with periodate-lysine-paraformaldehyde. Their incisors were dissected out, demineralized with EDTA, and prepared into 6-microns-thick frozen sections. The sections, which had been treated by means of antibody incubation for type-IV collagen, were washed with a Trismaleate buffer, incubated in Novikoff's medium for acid phosphatase (ACPase), and then incubated in a 3, 3'-diaminobenzidine solution. After osmification, the sections were embedded in epoxy resin for electron microscopy. The plasma membranes of the distal ends of the inner-enamel-epithelial cells were relatively even and were lined with a basement membrane. Type-IV collagen was localized both in the lamina densa and in the filaments attached to the lamina densa. In differentiating ameloblasts, the remarkably undulating distal plasma membranes formed irregular shallow and deep invaginations, and small cytoplasmic processes that penetrated the basement membrane. Coated pits occurred in various parts of these undulating plasma membranes. Positive reaction to type-IV collagen was observed in the invaginations and coated pits. ACPase-positive granules, present in inner-enamel-epithelial cells, increased in number and sometimes appeared close to both shallow and deep invaginations of differentiating ameloblasts. These results indicate that type-IV collagen in the basement membrane of the enamel organ is removed and degraded by differentiating ameloblasts by means of their engulfing system.

LV volume quantification via spatiotemporal analysis of real-time 3-D echocardiography.

This paper presents a method of four-dimensional (4-D) (3-D + Time) space-frequency analysis for directional denoising and enhancement of real-time three-dimensional (RT3D) ultrasound and quantitative measures in diagnostic cardiac ultrasound. Expansion of echocardiographic volumes is performed with complex exponential wavelet-like basis functions called brushlets. These functions offer good localization in time and frequency and decompose a signal into distinct patterns of oriented harmonics, which are invariant to intensity and contrast range. Deformable-model segmentation is carried out on denoised data after thresholding of transform coefficients. This process attenuates speckle noise while preserving cardiac structure location. The superiority of 4-D over 3-D analysis for decorrelating additive white noise and multiplicative speckle noise on a 4-D phantom volume expanding in time is demonstrated. Quantitative validation, computed for contours and volumes, is performed on in vitro balloon phantoms. Clinical applications of this spaciotemporal analysis tool are reported for six patient cases providing measures of left ventricular volumes and ejection fraction.

Evaluation of mitral valve disease using transesophageal echocardiography.

In the past 10 years, clinical application of transesophageal echocardiography (TE) has grown explosively. Intraoperative TE offers a powerful diagnostic and monitoring tool for the physicians in the cardiac operating room. The use of TE revolutionizes the assessment of patients with mitral valve disease. Surgical decisions are often altered based on the information obtained from TE. This review describes the basic features of TE as well as its uses in the intraoperative setting for evaluation of the mitral valve.

Changes in colonic mucosal permeability in mouse colitis induced with dextran sulfate sodium.

In this study we examined changes in colonic mucosal permeability induced by dextran sulfate sodium (DSS) during the acute phase of mouse colitis. To induce colitis, the mice were given drinking water containing 5% (w/v) DSS (MW = 40,000) ad libitum. Colonic mucosal permeability was evaluated by the permeation of Evans blue (EB) from the lumen into the wall of the colon on 1, 2, 3 and 7 days postadministration of DSS. Mucosal changes were also histologically examined daily for 7 days postadministration. The permeation of EB increased significantly by days 3 and 7 postadministration. Histological analysis showed that crypt loss was the initial change, with no inflammatory process and the surface mucosal epithelial cells remained morphologically intact. These histological changes developed on 2 to 3 days postadministration. Erosion was first recognized at 5 days postadministration. These findings indicated that the increase in colonic mucosal permeability may have occurred in 3 days postadministration, and the increase in mucosal permeability occurred before the appearance of the inflammatory process. This suggests that an increase in colonic mucosal permeability, leading to the destruction of mucosal barrier function, may play an important role in the induction of DSS-induced murine colitis.

Histological analysis of murine colitis induced by dextran sulfate sodium of different molecular weights.

In this study, we examined the relationship between the molecular weight of dextran sulfate sodium (DSS) and the features of colitis in a DSS-induced mouse model of human ulcerative colitis. DSS at three different molecular weights, 5 kD, 40 kD and 500 kD, was used in this study. DSS was administered in drinking water at 5% (w/v) to 6-7-week-old female BALB/c mice. After 7 days of treatment with DSS, the large intestine was examined histopathologically. Colitis was characterized by a loss of crypts, infiltration of inflammatory cells into the mucosa and submucosa, edema of the submucosa, erosion and ulceration and was observed in mice given the 5 kD and 40 kD forms but not the 500 kD. In the 5 kD group, colitis was observed predominantly in the cecum and upper colon. Colitis in the 40 kD group was more severe than that in the 5 kD group, and in the 40 kD group it was more severe in the lower colon than in the upper colon. These findings suggest the molecular weight of DSS to be an important factor in the murine model of colitis.

Isolation of xylose reductase gene of Pichia stipitis and its expression in Saccharomyces cerevisiae.

A NADPH/NADH-dependent xylose reductase gene was isolated from the xylose-assimilating yeast, Pichia stipitis. DNA sequence analysis showed that the gene consists of 951 bp. The gene introduced in Saccharomyces cerevisiae was transcribed to mRNA, and a considerable amount of enzyme activity was observed constitutively, whereas transcription and translation in P stipitis were inducible. S. cerevisiae carrying the xylose reductase gene could not, however, grow on xylose medium, and could not produce ethanol from xylose. Since xylose uptake and accumulation of xylitol by S. cerevisiae were observed, the conversion of xylitol to xylulose seemed to be limited.

Tissue distribution of dextran sulfate sodium (DSS) in the acute phase of murine DSS-induced colitis.

In the present study, we examined histochemically the tissue distribution of dextran sulfate sodium (DSS) in the acute phase of murine colitis induced by administering DSS in the drinking water. DSS was mainly observed in the Kupffer cells of the liver, in the macrophages of the mesenteric lymph node (MLN) and in the lamina propria of the large intestine after administration of DSS. We followed the time course of DSS distribution and found that DSS, which was considered as a large and negatively charged molecule that can not easily cross membranes, was distributed in the liver, the MLN, and the large intestine 1 day after the start of administration of DSS.

[Jichi Medical School Social Support Scale (JMS-SSS) revision and tests for validity and reliability].

OBJECTIVE: To develop a perceived social support scale for the Japanese. METHODS: Participants consisted of a total of 2,150 residents who responded to a perceived social support scale questionnaire in four communities involved in the Jichi Medical School Cohort Study at the study baseline in 1992-1994 (Analysis I) and 380 residents of Akaike town who responded to a questionnaire survey with the revised scale in 1999 (Analysis II). The first analysis was performed to confirm cross validity of the perceived social support scale measuring the availability of functional support from the spouse, family, and friends. The factor structures estimated for each district were compared with each other. The second analysis was set to revise the scale, modified in terms of a 4-point scoring format. The correlation between each item and a social desirability scale score, Cronbach alpha, and correlation coefficients between the revised scale scores and the original scale scores were calculated. RESULTS: Cross validity was confirmed based on the similarity of the factor structures of the responses obtained from the four different communities. Four selected indices supported the constancy of the factor structures across the communities. For the revised scale, two items were removed from the original scale-items measuring spousal support because of their statistically significant correlations with the social desirability scale score. The first principal component accounted for 57.0% of variance for spousal support, 68.2% for family support, and 67.0% for friends support and uni-dimensionality of the scales was confirmed. Alpha coefficients of the scales were .89, .95, and .94, respectively. Social support levels were stable over a mean period of 6.2 years. CONCLUSIONS: On an empirical basis, we have been able to develop a perceived social support scale. Homogeneous data from three different sources were obtained which were free from social desirability response bias and thus applicable for Japanese adults.

[Development of a perceived social support scale: for a Japanese population].

Social support is increasingly attracting interest in as a factor in epidemiological research of disease risks. However, at present, few methods for measuring social support that can be credited as having reliability and validity exist in Japan. Therefore a perceived social support scale was developed in relation to a population study of a town in Fukuoka prefecture. A method for measuring functional support from several external sources was designed consisting of a self-administered test provided with only two available response options--yes & no. Pretests were conducted twice in order to evaluate content validity and adjust the number of determinants and resulted in spouse, family members, and friends being selected to be primary sources of support. A factor analysis was applied to select 10 conditions with high internal consistency for each of the sources. Responses were scored 0 or 1, for 'no' or 'yes,' respectively. Subsequently each set of 10 variables was summed into an index ranking social support conditions for each of the three sources. The three highest ranking indicators from each of the respective sources were then integrated into a single comprehensive total social support score of the individuals. The inquiry method was applied on 277 adults, aged from 40 to 69 years, in the town. Intercorrelation between the indicators of support derived from the three sources was low and coefficients of reliability ranged from 0.892 to 0.978. The score of each set of the 10 variables were incorporated into a principal components analysis in order to determine factorial validity. All of the first factor loadings of the items measuring support from both spouse and family were greater than 0.7 and high eigenvalues were obtained. Therefore the methods applied to spouse and family were considered adequate to measure a given construct. The items measuring support from friends were divided into two factors, emotional support and tangible support.

[A case of bronchial rupture and pulmonary laceration caused by blunt chest trauma].

A 37-year-old female was crushed by a traffic accident. She was in severe respiratory distress. A chest X-ray revealed right pneumothorax and multiple rib fractures. Shortly after the initiation of the positive pressure ventilation, severe subcutaneous emphysema developed and she became shock. The bronchoscopy showed the rupture of the right main bronchus which was repaired through a right posterolateral thoracotomy using interrupted monofilament PPP sutures. Pulmonary lacerations were also repaired by the same sutures. Postoperative bronchoscopic examination showed good healing without any stricture. It cannot be overemphasized that accurate diagnosis and urgent surgical management is mandatory in patients with bronchial rupture.