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101.
OBJECTIVE: To determine the most suitable staining method for preservation and detection of calcium pyrophosphate dihydrate (CPPD) crystals in histological sections of patients with CPPD crystal deposition disease. METHODS: Paraffin sections of CPPD crystal-bearing tissues of 31 patients were stained with hematoxylin and eosin (H&E) and Alizarin red S (ARS). For H&E, the sections were treated with Mayer's hematoxylin (pH 2.3) for 5 min and with eosin alcohol (pH 4.1) for 1 min. For ARS, 1% ARS dissolved in distilled water was adjusted to pH 6.4 by adding 0.1% ammonia solution drop by drop while stirring. As controls, unstained sections were soaked in 1% citric acid monohydrate solution (CAMS, pH 2.3) for 5 or 10 min. The histological preparations were examined under a compensated polarized light using a first-order red compensator. We counted the number of weakly positive birefringent CPPD crystals in 3 high power fields (HPF, 0.272 mm2). RESULTS: CPPD crystals were seen clearly in most specimens stained with ARS, but were markedly reduced in tissue sections stained with H&E or CAMS. The number of CPPD crystals detected in sections stained by ARS (1723 +/- 683 per 3 HPF, mean +/- standard deviation) was significantly higher compared with H&E, CAMS (5 min), and CAMS (10 min) (401 +/- 374, 1022 +/- 616, and 494 +/- 636 per 3 HPF, respectively; p < 0.001, each). CONCLUSION: Standard H&E staining reduces the number of visible CPPD crystals, probably due to the strong acidity of both hematoxylin and eosin solutions, whereas the ARS stain seems to preserve a large number of CPPD crystals. The utility of ARS staining may improve the identification of CPPD crystals and contribute to a correct diagnosis of CPPD crystal deposition.  相似文献   
102.
PURPOSE: The aim of this study was to clarify the distribution of lymph node metastasis in colorectal cancer. We also examined the relationship between the primary tumor (T) and the regional node (N) categories of the TNM (primary tumor, regional nodes, metastasis) classification. METHOD: Lymph nodes of surgical specimens in 311 consecutive patients with colorectal cancer were studied using the modified clearing method. RESULTS: Lymph node metastasis was seen in 59.2 percent of the total cases. The upward metastasis rate was 30.7 percent. In the longitudinal spread, most of the lymph node metastasis was seen within 10 cm. On the oral side in rectal cancer, there was no metastasis beyond 4 cm. The lateral metastasis rate in rectal cancer was 8.8 percent and in the lower rectum, the rate of cancer within 6 cm from the anal verge or beyond pT3 was much higher. CONCLUSION: In the TNM classification, there was no significant difference between colon and rectal cancer except pT1 with rectal cancer. In the lower rectal cancer within 6 cm from the anal verge or beyond pT3, there is a high risk of lateral metastasis, and lateral lymph node dissection or radiation therapy should be performed.  相似文献   
103.

Background

We investigated the clinical course of complete right bundle branch block (RBBB) or RBBB with axis deviation (AD) in terms of subsequent pacemaker implantation for high-degree atrioventricular (AV) block or sick sinus syndrome (SSS).

Methods and results

Among the 16,170 atomic-bomb survivors in our biennial health examination between July 1967 and December 2010, we detected 520 newly-acquired RBBB subjects with no organic heart disease, and selected 1038 age- (at RBBB diagnosis) and sex-matched subjects without RBBB to serve as comparison subjects. Multivariate Cox regression analysis was used to estimate the hazard ratios (HRs) for the risk of pacemaker implantation due to all causes, AV block or SSS between RBBB and comparison subjects and between RBBB subjects with and without AD. The risk of pacemaker implantation for RBBB was 4.79 (95% confidence interval [CI] 1.89–12.58; P = 0.001), 3.77 (95% CI, 1.09–13.07; P = 0.036), and 6.28 (95% CI, 1.24–31.73, P = 0.026) when implantation was for all causes, AV block and SSS, respectively. RBBB subjects with AD had a higher risk for all-cause pacemaker implantation than subjects without AD (HR, 3.03; 95% CI, 1.00–9.13, P = 0.049). RBBB subjects with AD were younger than subjects without AD at the time of RBBB diagnosis (59.4 ± 7.6 vs 74.4 ± 3.1 years old, P = 0.019), and their progression from diagnosis to pacemaker implantation took longer (15.1 ± 6.6 vs 6.4 ± 3.0 years, P = 0.032).

Conclusions

RBBB, especially with AD, progresses to AV block and SSS that requires pacemaker implantation; the mechanisms by which the conduction defect progresses differ among patients with and without AD.  相似文献   
104.
The enzyme 3β-hydroxysteroid dehydrogenase/isomerase (3β-HSD) is essential for the biosynthesis of all active steroid hormones, such as those secreted from the adrenal gland, testis, ovary, skin and placenta. The 3β-HSD enzymes exist in multiple isoforms in humans and rodents. To date, six different isoforms have been identified in the mouse, and these isoforms are speculated to play different roles in different tissues. We previously showed that the murine type VI 3β-HSD isoform (Hsd3b6) is expressed specifically in the aldosterone-producing zona glomerulosa cells within the adrenal gland and that its overexpression causes abnormally increased aldosterone synthesis, revealing a crucial (or rate-limiting) role of this enzyme in steroidogenesis. However, potential contributions of this enzyme to the steroid hormone synthesis outside the adrenal glands are poorly understood. This paucity of knowledge is partly because of the lack of isoform-specific antibody that can be used for immunohistochemistry. Here, we report the development and characterization of specific antibody to Hsd3b6 and show the results of immunohistochemistry for the adrenal gland, testis, ovary, skin and placenta. As expected, Hsd3b6 immunoreactivities within the adrenal gland were essentially confined to the zona glomerulosa cells, where aldosterone is produced. By contrast, no immunopositive cells were observed in the zona fasciculata, which is where corticosterone is produced. In the gonads, while the ovaries did not show any detectable immunoreactivity to Hsd3b6, the testes displayed intense immunoreactivities within the interstitial Leydig cells, where testosterone is produced. In the skin, positive immunoreactivities to Hsd3b6 were only seen in the sebaceous glands, suggesting a specific role of this enzyme in sebaceous function. Moreover, in the placenta, Hsd3b6 was specifically found in the giant trophoblast cells surrounding the embryonic cavity, which suggests a role for this enzyme in local progesterone production that is required for proper embryonic implantation and/or maintenance of pregnancy. Taken together, our data revealed that Hsd3b6 is localized in multiple specific tissues and cell types, perhaps thereby involved in biosynthesis of a number of tissue-specific steroid hormones with different physiological roles.  相似文献   
105.
106.
107.
The development of quantitative gated single-photon emission computed tomography (SPECT) has enabled the assessment of left ventricular perfusion, function and wall thickness in a single examination. Accordingly, the present study used gated SPECT to assess the benefit of coronary artery bypass grafting (CABG) in patients with coronary artery disease; 47 of those patients were evaluated before and 5 months after CABG. As a result of coronary revascularization, a significant improvement was observed in global ejection fraction (50+/-12 --> 53+/-11%; p<0.05). In 107 revascularized territories, the average regional reversible defect score (0.8+/-0.5 --> 0.2 +/-0.3; p<0.0001), average regional perfusion score at rest (0.6+/-0.6 --> 0.3+/-0.4; p<0.0001), average regional wall motion score (0.9+/-0.7 --> 0.7+/-0.5; p<0.05), and end-diastolic wall thickness (8.1+/-1.3 --> 8.6+/-1.5 mm; p<0.0005) all improved significantly. Even in 34 non-revascularized territories, the average regional reversible defect score (0.5+/-0.7 --> 0.2+/-0.5; p<0.03), average regional wall motion score (0.8+/-1.1 --> 0.5 +/-1.0; p<0.03) and end-diastolic wall thickness (8.0+/-1.4 --> 9.1+/-2.0 mm; p<0.03) all improved significantly. These results indicate that improvement in myocardial ischemia, hibernation and left ventricular function with CABG can be assessed in detail with gated SPECT.  相似文献   
108.
AIM: The objective of this longitudinal study was to evaluate the growth of the fetal spleen in normal pregnancies, using three-dimensional ultrasound. METHODS: Three-dimensional sonographic examinations were performed on 14 appropriate-for-gestational-age fetuses. Fetal splenic volume was measured every 2-3 weeks after 20 weeks of gestational age until delivery. RESULTS: Curvilinear relationships were found between the gestational age and splenic volume (R(2) = 80.2%, P < 0.0001), and normal ranges of splenic volume measurements for estimating the growth of the fetal spleen during normal pregnancy were generated. We found that the splenic volume calculation based on the equation for the volume of the ellipsoid by conventional two-dimensional ultrasound in previous investigations is about twice as large as that using three-dimensional ultrasound in our study, whereas the present data described in this study is quite comparable with previous data from an autopsy series. CONCLUSION: Our findings suggest that the standard curve for the fetal splenic volume using three-dimensional ultrasound provides a superior means for evaluating the normal splenic growth in the fetus and for identifying splenic abnormalities in utero. However, the data and its interpretation in our study should be taken with some degree of caution because of the small number of subjects studied. Further studies involving a larger sample size would be needed to confirm these findings.  相似文献   
109.
We investigated the wetting transitions of tetradecane and hexadecane droplets in dodecyltrimethylammonium bromide (C12TAB), tetradecyltrimethylammonium bromide (C14TAB), and hexadecyltrimethylammonium bromide (C16TAB) aqueous solutions. By varying the surfactant concentration, the formation of mixed monolayers of a surfactant and an alkane was observed at the air–water interface. Depending on the combination of surfactant and alkane, these wetting monolayers underwent another thermal phase transition upon cooling either to a frozen mixed monolayer (S1) or a bilayer structure composed of a solid monolayer of a pure alkane rested on a liquid-like mixed monolayer (S2). Based on the phase diagrams determined by phase modulation ellipsometry, the difference in the morphology of the nucleated S1 and S2 phase domains was also investigated using Brewster angle microscopy. Domains of the S1 phase were relatively small and highly branched, whereas those of the S2 phase were large and circular. The difference in domain morphology was explained by the competition of the domain line tension and electrostatic dipole interactions between surfactant molecules in the domains.  相似文献   
110.
There are few case reports of hepatocellular carcinoma (HCC) metastasis to the skeletal muscle. A 78-year-old man developed a mass in the right shoulder. Washout of contrast medium during contrast-enhanced ultrasonography (CEUS) in both the primary HCC and the metastatic site was detected. Several nodules were scattered throughout the liver on an autopsy. In addition, the moderately differentiated HCC had metastasized to the right teres major muscle. Rare muscular metastasis should be considered if a hepatic tumor is moderately or poorly differentiated HCC. Early washout during CEUS is consistent with a pathological diagnosis of moderately or poorly differentiated HCC.  相似文献   
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