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91.
Bone deposition and bone resorption are ongoing dynamic processes, constituting bone remodeling. Some bone tumors, such as osteosarcoma (OS), stimulate focal bone deposition. OS is the most common primary bone tumor in children and young adults. A complex network of genes regulates bone remodeling and alterations in its expression levels can influence the genesis and progression of bone diseases, including OS. We hypothesized that the expression profiles of bone remodeling regulator genes would be correlated with OS biology and clinical features. We used real‐time PCR to evaluate the mRNA levels of the tartrate‐resistant acid phosphatase (ACP5), colony stimulating factor‐1 (CSF1R), bone morphogenetic protein 7 (BMP7), collagen, type XI, alpha 2 (COL11A2), and protein tyrosine phosphatases zeta 1 (PTPRZ1) genes, in 30 OS tumor samples and correlated with clinical and histological data. All genes analyzed, except CSF1R, were differentially expressed when compared with normal bone expression profiles. In our results, OS patients with high levels of COL11A2 mRNA showed worse overall (p = 0.041) and event free survival (p = 0.037). Also, a trend for better overall survival was observed in patients with samples showing higher expression of BMP7 (p = 0.067). COL11A2 overexpression and BMP7 underexpression could collaborate to OS tumor growth, through its central role in bone remodeling process. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:1142–1148, 2010  相似文献   
92.
Staghorn stones represent a therapeutic challenge to urologists. We present our experience with laparoscopic extended pyelolithotomy for treatment of staghorn and complex renal calculi in highly selected cases. This approach provides the principles of open surgery with the advantages of minimally invasive surgery. We describe our experience with robot-assisted extended pyelolithotomy for complex coralliform calculi. Since January 2007, robotic extended pyelolithotomy has been performed by transperitoneal approach in two patients with complete coralliform lithiasis (calculi average size 8 cm). One patient had history of percutaneous nephrolithotomy. Demographic and operative data were collected. All procedures were technically successful without need for open conversion. Mean estimated blood loss was 175 ml (range 50–300 ml), and mean operative time was 150 min (range 120–150 min). A perinephric drain was employed in one patient with duration of 5 days. Postoperative imaging confirmed complete stone clearance. Robotic extended pyelolithotomy is a feasible and reproducible procedure for removal of complete and partial staghorn calculi in selected patients with complex nephrolithiasis. This approach might limit the role of open surgery for these calculi, but further publications with more cases are necessary to further define its utility.  相似文献   
93.
The heterotopic pregnancy is a combination of an intra-uterine and extra-uterine pregnancy, at the same time. The spontaneous heterotopic pregnancy is a rare illness with an estimated frequency below one per 20,000 and one per 30,000. The first case was reported in France by Duverney in 1708 during an autopsy. The frequency of this pregnancy has increased with the implementation of assisted reproduction techniques. This paper is the report of a case of spontaneous heterotopic pregnancy seen at the Angeles Mexico Hospital. A 32 year old woman, gravida 1; dilatation and curettage was performed on 13th February because of a blighted ovum, a lot of products of conception were obtained. The patient was discharged the next day only with analgesics. She returns to the emergency room on February 16th with hypovolemic shock and acute abdomen. A normocitic normocromic anemia was found on the hematic biometry, the transvaginal ultrasound reported amount of blood in the cul-de-sac, echogenic adnexal mass, suggesting a gestational sac with embryo. An emergency laparotomy was used to perform a left cornual resection; the findings were 600 cc of hemoperitoneum and a left ruptured ectopic pregnancy. She had an uneventful postoperative course, and was discharged 72 hours later without complications. Heterotopic pregnancy is a rare illness and must always be considered for the increase in pregnancy related with assisted reproduction techniques, although, it should be considered in a spontaneous pregnancy too.  相似文献   
94.
The search for molecular markers to improve diagnosis, individualize treatment and predict behavior of tumors has been the focus of several studies. This study aimed to analyze homeobox gene expression profile in oral squamous cell carcinoma (OSCC) as well as to investigate whether some of these genes are relevant molecular markers of prognosis and/or tumor aggressiveness. Homeobox gene expression levels were assessed by microarrays and qRT-PCR in OSCC tissues and adjacent non-cancerous matched tissues (margin), as well as in OSCC cell lines. Analysis of microarray data revealed the expression of 147 homeobox genes, including one set of six at least 2-fold up-regulated, and another set of 34 at least 2-fold down-regulated homeobox genes in OSCC. After qRT-PCR assays, the three most up-regulated homeobox genes (HOXA5, HOXD10 and HOXD11) revealed higher and statistically significant expression levels in OSCC samples when compared to margins. Patients presenting lower expression of HOXA5 had poorer prognosis compared to those with higher expression (P=0.03). Additionally, the status of HOXA5, HOXD10 and HOXD11 expression levels in OSCC cell lines also showed a significant up-regulation when compared to normal oral keratinocytes. Results confirm the presence of three significantly upregulated (>4-fold) homeobox genes (HOXA5, HOXD10 and HOXD11) in OSCC that may play a significant role in the pathogenesis of these tumors. Moreover, since lower levels of HOXA5 predict poor prognosis, this gene may be a novel candidate for development of therapeutic strategies in OSCC.  相似文献   
95.
This study aimed to present a wireless mandibular motion tracking device and optoelectronic data acquisition system developed to analyze the real-time spatial motion of the entire mandible during mouth opening and closing with no restriction of any movement. The procedures were divided into three phases: confection of a kinematic arch, dynamic digital video image acquisition, and image processing and analysis by using graphic computation. Four sequences of jaw opening/closing movements were recorded in lateral view: two from the maximum intercuspation (MIC) and the other two from a forced mandibular retruded position. Jaw motion was recorded by a digital video camera and processed as spatial coordinates corresponding to the position variation of the markers in the kinematic arch. The results showed that the method was capable of recording and processing the dynamics of the mandibular movements during jaw opening/closing using pixel-magnitude points. The mandible showed points with less displacement located near the temporomandibular joint during the opening/closing movements from the mandibular retruded position. When the jaw movements were recorded from MIC, these points were located near the mandibular foramen.  相似文献   
96.
97.
Acoustic neuromas are the most common tumors in the cerebellopontine angle. The molecular mechanisms involved in generation and growth of these tumors are not completely elucidated. Many radiological, clinic and immunohistochemistry data were correlated to tumor growth. We studied 11 acoustic neuromas surgically treated at Hospital S?o Paulo/Unifesp and correlated clinical and radiological data with proliferative index (Ki-67). The size of the tumors were positively correlationated with proliferative index. No other correlation had statistic significativity.  相似文献   
98.
OBJECTIVE: The aim of this study is to correlationate demographic, radiologic features and proliferative index defined by immunohistochemical expression of Mib-1 in olfactory groove meningiomas, and to observe possible predictive factors of recurrence of this tumor. METHOD: There were analysed demographic, clinical and radiological features of 15 patients with olfactory groove meningioma. Fifteen paraffin-embebed tumors were studied by immunohistochemical methods for the expression of proliferative index by the Mib-1. RESULTS: There was a statistically positive correlation between tumoral and edema volumes. There was no correlation between Mib-1, tumoral volume, tumoral edema and frontal skull base abnormalities. Two cases with tumor recurrence had proliferative indices higher than the mean index. CONCLUSION: Larger tumors were more susceptible to develop peritumoral edema. The proliferative índex has no positive correlation with tumoral volume, edema volumes and skull base invasion, but probably it is associated with tumoral recurrence.  相似文献   
99.
Posterior longitudinal ligament ossification of cervical spine is a rare condition among caucasians. A 42 years old japanese patient with progressive walking difficulty was diagnosed with this pathology by CT scan and MRI and treated surgically by an anterior approach with arthrodesis. Pathophysiology, racial prevalence, clinical picture, radiological characteristics and surgical approaches options are revised.  相似文献   
100.
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