Association of vitamin D and estrogen receptor gene polymorphism with the effects of longterm hormone replacement therapy on bone mineral density

We longitudinally studied whether vitamin D receptor (VDR) and estrogen receptor (ER) gene polymorphisms in Japanese women influenced the effect of longterm hormone replacement therapy (HRT) on bone mineral density (BMD) in the lumbar spine. The 81 subjects were aged 40 to 64 years (mean ± SEM, 49.5 ± 0.6 years), and had received sequential or continuous HRT regimens, including 0.625mg of conjugated equine estrogen and 2.5 to 5mg of medroxy-progesterone acetate, for at least 3 years. Genomic DNA was extracted from blood cells, and analyzed for restriction fragment length polymorphism, using the restriction endonucleases Taq I, Apa I, and Fok I for VDR, and Pvu II and Xba I for ER. At 1 year, subjects with a Taq I genotype of TT (i.e., site absent) showed a significantly greater increase in BMD with treatment (BMD) than subjects with the Tt genotype (2.6 ± 0.5% vs –0.8 ± 1.4%; P = 0.016). A small difference between genotypes remained at 2 years (3.8 ± 0.6% vs 0.8 ± 1.6%; P = 0.069), but no significant difference between genotypes was seen at 3 years. In multiple regression analyses, BMD at 1 year was significantly affected by VDR-Taq I, Apa I, and ER-Pvu II genotypes and by age at treatment initiation, although at 3 years or more, BMD was significantly affected only by age. These results indicate that Taq I VDR gene polymorphism predicted the effect on lumbar BMD for the first year of HRT in Japanese women, and that the differences in BMD versus the polymorphism disappeared if the treatment was continued for over 2 years.     

Magnetic resonance imaging for preoperative evaluation of breast cancer: a comparative study with mammography and ultrasonography

BACKGROUND: The widespread use of mammographic screening has led to increased detection of small tumors that are often difficult to diagnose with conventional imaging modalities such as mammography and ultrasonography. Intraductal spread of breast cancer, a principle risk factor for local recurrence, is also difficult to diagnose with mammography and ultrasonography. We investigated the clinical usefulness of magnetic resonance imaging of the breast in the therapy of breast cancer and we compared it with mammography and ultrasonography. STUDY DESIGN: A total of 183 patients with primary breast cancer underwent surgery at our institute between September 1, 1999, and November 30, 2002. They were examined preoperatively with magnetic resonance imaging, mammography, and ultrasonography. Magnetic resonance imaging evaluation included contrast-enhanced dynamic studies using IV injection of gadolinium-diethylenetriamine pentaacetic acid. RESULTS: Detection rates of breast cancers by magnetic resonance imaging, mammography, and ultrasonography were 93.7%, 84.6%, and 97.3%, respectively (magnetic resonance imaging versus mammography, p < 0.05). Patterns of time-intensity curves in dynamic magnetic resonance imaging differed with histologic types. Sensitivity, specificity, and accuracy of detection of intraductal spread were 66.7%, 64.2%, and 65.6% with MRI; 22.2%, 85.7%, and 50% with mammography; and 20.6%, 85.2%, and 50% with ultrasonography, respectively (sensitivity, specificity, and accuracy; p < 0.05, respectively). CONCLUSIONS: Magnetic resonance imaging can diagnose breast cancer as accurately as ultrasonography and more accurately than mammography. Patterns of time-intensity curves correlated with tumor histology. In addition, magnetic resonance imaging can detect intraductal spread more accurately than the other two methods. Magnetic resonance imaging appears to be indispensable in breast-conserving surgery to minimize local recurrence.     

Lymph node metastasis in T1 adenocarcinoma of the colon and rectum

The biology of colorectal cancer differs according to location within the large intestine. To evaluate the clinical significance of tumor location as a risk factor for lymph node metastasis (LNM), we performed a detailed pathological review of T1 adenocarcinomas of the colon and rectum. T1 adenocarcinomas of the colon and rectum treated by radical resection (n = 428) were identified from prospective clinical databases at two institutions. Tumor location was assigned as right colon (cecum to transverse), left colon (splenic flexure to sigmoid), or rectum (0–18 cm from AV). Pathology slides were reviewed, extent of submucosal invasion (sm width, sm depth) was quantified using an optical micrometer, and morphologic features of the cancer and its infiltrating margin were recorded. The overall rate of LNM was 10%. On univariate analysis, LNM was significantly more common in the rectum (27/176, 15%) compared to the left colon (13/160, 8%, p = .04) or right colon (3/92, 3%, p = .003). However, on multivariate analysis, deep submucosal invasion and lymphovascular invasion were independent and significant risk factors, whereas tumor location was not. T1 colorectal cancers have a progressively higher risk of LNM as their location becomes more distal. However, the increasing rate of LNM observed in cancers of the left colon and rectum is explained by a higher prevalence of high-risk pathologic features. In early colorectal cancers, tumor morphology is the strongest clinical predictor of metastatic behavior. Presented at the Forty-Fifth Annual Meeting of The Society for Surgery of the Alimentary Tract, New Orleans, Louisiana, May 15–19, 2004 Presented at the Forty-Fifth Annual Meeting of The Society for Surgery of the Alimentary Tract, New Orleans, Louisiana, May 15–19, 2004     

The retention indices of 201Tl-SPECT in brain tumors

OBJECTIVE: The aim of this study was to assess the utility of 201Tl SPECT in the differential diagnosis of intracranial tumors and to determine the relationship between 201Tl uptake and histological types. METHODS: Thirty-eight patients (19 males and 19 females) with thirty-eight brain tumors were evaluated with 201Tl-SPECT. The early and delayed 201Tl uptake ratio was calculated, and the retention index (RI) was applied as follows; RI = delayed uptake ratio/early uptake ratio. RESULTS: The RI of malignant tumors was higher (0.72 +/- 0.18) than that of benign tumors (0.50 +/- 0.16) and the difference was statistically significant (p = 0.00045). The difference between high-grade glioma (0.80 +/- 0.15) and metastatic tumors (0.64 +/- 0.19) was statistically significant (p = 0.039). CONCLUSION: 201Tl-SPECT may add useful biochemical information and could differentiate malignant brain tumors from benign lesions, but the RI of metastatic tumors varied depending on the organs with the primary lesion and histological types.     

Multi-center study for the evaluation of clinical usefulness of attenuation and scatter correction on 201Tl myocardial SPECT

The aim of this study was to evaluate the clinical usefulness of attenuation and scatter correction (AC, SC) on a 201Tl myocardial single-photon emission computed tomography (201Tl SPECT) as a multi-center trial. With a dual-detecter and a triple-detector SPECT systems with a 99mTc transmission source, simultaneous transmission/emission tomography (TCT/ECT) was performed on 38 patients with angiographically coronary heart disease (CHD) and 26 patients without evidence of CHD. Stress and delayed attenuation and scatter corrected images (SAC) and uncorrected images (NC) were reconstructed. On NC images of normal cases, influence of attenuation was greater in male than female. In comparison of 201Tl distribution between male and female, significant decrease in 201Tl activity was observed in the inferoposterior wall in male and that was observed in the anterobasal wall of the left myocardium in female. Such a difference in 201Tl distribution between male and female disappeared on SAC images. On the diagnostic performance for the identification of CHD, SAC images demonstrated improved specificity and accuracy values in the right coronary arterial territory (RCA) with visual analysis statistically. Sensitivity value in the RCA was also improved, but it was not statistically significant. Sensitivity value in the left circumflex arterial territory (LCX) increased without decrease in specificity value on SAC images. In the left anterior descending arterial territory (LAD), sensitivity value increased on SAC images. Although specificity value decreased on SAC images in LAD territory, it was not statistically significant. The difference in 201Tl distribution between male and female is improved in normal cases by attenuation and scatter correction on 201Tl myocardial SPECT. Diagnostic performance of CHD is also improved by attenuation and scatter correction, especially in territories of which specificity in assessing the absence of disease have been suboptimal. In conclusion, attenuation and scatter correction on 201Tl myocardial SPECT is considered to be clinically useful.     

Hepatocyte differentiation from embryonic stem cells and umbilical cord blood cells

With the development of regeneration medicine, many researchers have attempted hepatic differentiation from nonhepatic-origin cell sources. The differentiation of embryonic stem (ES) cells into hepatocyte-like cells has been reported in several papers. Mouse ES cells have shown a potential to develop into hepatocyte-like cells in vitro on the basis of hepatic gene expression after adding several growth factors. We transplanted cultured embryoid body (EB) cells (male) into female mice. A liver specimen of the recipient was examined by immunohistochemical staining for albumin and fluorescence in situ hybridization for the Y chromosome after transplantation. Both Y chromosome- and albumin-positive cells were recognized in the recipient female liver, and were considered to be hepatocyte-like cells derived from ES cells containing the Y chromosome. Many groups, including ourselves, have studied hepatocyte-like cell differentiation from umbilical cord blood cells (UBCs). We cultured nucleated cells isolated from UBCs. Using immunostaining, ALB-positive and CK-19-positive cells were recognized in the culture. Dual staining of ALB and CK-19 demonstrated that ALB was coexpresed with CK-19, suggesting the existence of hepatic progenitors. In this review, we consider recent studies of the differentiation of hepatocytes from nonhepatic origins, especially ES cells and umbilical cord blood.     

Drug delivery system using microspheres that contain tacrolimus in porcine small bowel transplantation

Rejection remains a major barrier to successful bowel transplantation, in spite of improved immunosuppressive techniques. Therefore, new, more effective, immunosuppressants, with fewer side effects, are needed. Biodegradable microspheres containing tacrolimus (FK506) were used in an experimental porcine small bowel transplantation. Twenty pigs underwent transplantation and were divided into four groups according to the immunosuppressive regimen. Group A (n=5): no immunosuppression; group B (n=6): 0.2 mg/kg per day of FK506; group C (n=3): 1.0 mg/kg per day of FK506; group D (n=6): 0.04 mg/kg per day of FK506 contained in biodegradable microspheres. Rejection was diagnosed macroscopically by endoscopic examination and histologically by biopsy specimen analysis. The mean survival time and standard deviation (SD) were 8.8±3.5, 11.0±1.4, 9.7±2.5 and 28.6±22.5 days for groups A, B, C, and D, respectively, with a statistically significant difference found between group D, on the one hand, and groups A, B and C, on the other. The mean trough blood concentration of FK506 was 10.5±2.2, 27.9±6.0 and 10.5±3.5 ng/ml in groups B, C and D, respectively. In groups A and B, all pigs died of rejection, without infection. In group C, all died of infection, without rejection. In contrast, none of the pigs in group D developed rejection or infection. Our results clearly show that the drug delivery system using biodegradable microspheres that contain FK506 is effective for controlling rejection with fewer side effects in the porcine small bowel transplantation.     

Effect of the free radical scavenger MCI-186 on spinal cord reperfusion after transient ischemia in the rabbit

Objective: Paraplegia remains a serious complication of aortic operations. The production of free radicals during reperfusion after transient ischemia is believed to induce secondary spinal neuronal injury, resulting in paraplegia. The aim of the present study was to clarify the protective effect and method of administration of antioxidants on the neurological and histological outcome in the animal model for reperfusion injury after transient spinal cord ischemia. Methods: New Zealand white rabbits underwent surgical exposure of the abdominal aorta that was clamped for 15 minutes to achieve spinal cord ischemia. Group A animals received two 10 mg/kg doses of 3-methyl-l-phenyl-2-pyrazolin-5-one (MCI-186) at the time of release of the aortic clamp and 30 minutes later. In group B, MCI-186, 5 mg/kg, was given three times, at the time of aorta clamp release, 30 minutes and 12 hours later. In group C (control group), one dose of vehicle was administered. Neurological status was assessed using modified Tarlov’s score until 168 hours after operation. Spinal cord sections were examined microscopically to determine the extent of ischemic neuronal damage. Results: Groups A and B animals had better neurological function than group C (p(0.001). In contrast, group C animals exhibited paraplegia or paraparesis with marked neuronal necrosis. The number of surviving neurons within examined sections of the spinal cord was significantly greater in group B than in group C (p(0.001). Conclusion: In a 15-minute ischemia-reperfusion model using rabbits, systemic repetitious administration of MCI-186, a free radical scavenger, was found to have a protective effect on the spinal cord neurons both neurologically and histologically. We postulate that the drug minimizes the delayed neuronal cell death for reperfusion injury after transient ischemia by reducing the free radical molecules. Moreover, it was thought that we could protect delayed neuronal cell death more effectively by administering MCI-18612 hours later.     

Experimental studies on the effects of recombinant human matrix metalloproteinases on herniated disc tissues--how to facilitate the natural resorption process of herniated discs.

PURPOSE: Recently, MMP-7 and MMP-3 have been found to play a crucial role in the natural resorption process of herniated discs. We therefore examined the role of these recombinant human matrix metalloproteinases (rh MMPs) in the treatment of herniated discs. METHODS: (a) Surgical samples of herniated disc were cultured in the presence or absence of rh MMPs, and wet weight was measured 24h later. (b) The rh MMPs were administered into normal rabbit intervertebral discs, and after 1 week spine samples were stained with Safranin O. (c) The rh MMPs were administered into canine herniated discs in vivo. Myelography and MRI were performed prior to and 1 week after administration. Spine samples were examined histologically. Whole disc tissue was collected, total protein was extracted, and Western blot analysis was performed. RESULTS: (a) Proteoglycan degradation was found in MMP-7, MMP-3, and chymopapain-treated samples. MMP-7 and chymopapain-treated samples displayed a significant loss in wet weight (p<0.01). (b) Normal disc tissues after administration of rh MMP-7, MMP-3, and chymopapain showed an extensive loss of Safranin O staining. (c) The rh MMP-7-treated discs had a marked decrease in protruded herniation by MRI. Herniated discs after administration of MMP-7 and chymopapain showed a significant decrease in protruded mass 7 days after administration compared with saline-treated discs when evaluated by myelography (p<0.01). The rh MMP-7-treated discs displayed a clear loss of Safranin O staining in the nucleus pulposus. Proteoglycan expression was barely detectable in disc tissues after MMP-7 administration, whereas obvious expression was obtained in saline-treated or untreated disc tissues. CONCLUSIONS: Exposure to rh MMP-7 resulted in promising proteoglycan loss in human surgical samples, normal rabbit intervertebral discs, and natural canine herniated discs. Administration of rh MMP-7 may facilitate the resorption process of herniated discs.