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1.

Background

Notch receptors are critical determinants of cell fate in a variety of organisms. Notch signaling is involved in the chondrogenic specification of neural crest cells. Aberrant Notch activity has been implicated in numerous human diseases including cancers; however its role in chondrogenic tumors has not been clarified.

Method

Tissue samples from a case of primary chondrosarcoma of the maxilla and its recurrent tumor were examined immunohistochemically for Notch1-4 and their ligands (Jagged1, Jagged2 and Delta1) expression.

Results

Both primary and recurrent tumors were histopathologically diagnosed as conventional hyaline chondrosarcoma (WHO Grade I). Hypercellular tumor areas strongly expressed Notch3 and Jagged1 in spindle and pleomorphic cells suggesting up-regulation of these protein molecules at sites of tumor proliferation. Expression patterns were distinct with some overlap. Differentiated malignant and atypical chondrocytes demonstrated variable expression levels of Jagged1, and weak to absent staining for Notch1, 4 and Delta1. Protein immunolocalization was largely membranous and cytoplasmic, sometimes outlining the lacunae of malignant chondrocytes. Hyaline cartilage demonstrated a diffuse or granular precipitation of Jagged1 suggesting presence of soluble Jagged1 activity at sites of abnormal chondrogenesis. No immunoreactivity for the other Notch members was observed. Calcified cartilage was consistently Notch-negative indicating down-regulation of Notch with cartilage maturation. Stromal components namely endothelial cells and fibroblasts variably expressed Notch1, 3 and Jagged1 but were mildly or non-reactive for the other members.

Conclusions

Results indicate that Notch signaling pathway may participate in cellular differentiation and proliferation in chondrosarcoma. Findings implicate Notch3 and Jagged1 as key molecules that influence the differentiation and maturation of cells of chondrogenic lineage.  相似文献   

2.

Objective

Many mobile phone resources have been developed to increase access to health education in the developing world, yet few studies have compared these resources or quantified their performance in a resource-limited setting. This study aims to compare the performance of resident physicians in answering clinical scenarios using PubMed abstracts accessed via the PubMed for Handhelds (PubMed4Hh) website versus medical/drug reference applications (Medical Apps) accessed via software on the mobile phone.

Methods

A two-arm comparative study with crossover design was conducted. Subjects, who were resident physicians at the University of Botswana, completed eight scenarios, each with multi-part questions. The primary outcome was a grade for each question. The primary independent variable was the intervention arm and other independent variables included residency and question.

Results

Within each question type there were significant differences in ‘percentage correct’ between Medical Apps and PubMed4Hh for three of the six types of questions: drug-related, diagnosis/definitions, and treatment/management. Within each of these question types, Medical Apps had a higher percentage of fully correct responses than PubMed4Hh (63% vs 13%, 33% vs 12%, and 41% vs 13%, respectively). PubMed4Hh performed better for epidemiologic questions.

Conclusions

While mobile access to primary literature remains important and serves an information niche, mobile applications with condensed content may be more appropriate for point-of-care information needs. Further research is required to examine the specific information needs of clinicians in resource-limited settings and to evaluate the appropriateness of current resources in bridging location- and context-specific information gaps.  相似文献   

3.

Objective

Primary diffuse leptomeningeal gliomatosis (PDLG) is a rare neoplasm with a short survival time of a few months. there is currently no standardized therapeutic approach for PDLG.

Materials and methods

We report on a 53-year-old male patient who presented with epileptic seizures, gait disturbance, paraparesis and sensory deficits in the dermatomes T8-10.

Results

Magnetic resonance imaging (MRI) revealing numerous spinal and cranial gadolinium-enhancing nodules in the meninges and histopathology led us to diagnose primary diffuse leptomeningeal gliomatosis with WHO grade III astrocytic cells. Consecutively, the patient underwent craniospinal radiotherapy (30 Gy) and 11 sequential cycles of temozolomide. This regimen led to partial tumor regression. Thirteen months later, spinal MRI revealed tumor progression. Second-line chemotherapy with 5 cycles of irinotecan and bevacizumab did not prevent further clinical deterioration. The patient died twenty-two months after diagnosis, being the longest survival time described thus far with respect to PDLG consisting of astrocytic tumor cells.

Conclusions

Radiochemotherapy including temozolomide, as established standard therapy for brain malignant astrocytomas, might be valid as a basic therapeutic strategy for this PDLG subtype.  相似文献   

4.
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6.

Background

Symptomatic paroxysmal hypertension without significantly elevated catecholamine concentrations and with no evidence of an underlying adrenal tumor is known as pseudopheochromocytoma.

Methods

We describe the case of a female patient with paroxysmal hypertensive crises accompanied by headache, vertigo, tachycardia, nausea and altered mental status. Previously, she was treated for a longer period with alprazolam due to panic disorder. Causes of secondary hypertension were excluded. Neurological triggers (intracranial tumor, cerebral vascular lesions, hemorrhage, and epilepsy) could not be detected.

Results

Setting of the diagnosis of pseudopheochromocytoma treatment was initiated with alpha- and beta-blockers resulting in reduced frequency of symptoms. Alprazolam was restarted at a daily dose of 1 mg. The patient’s clinical condition improved rapidly and the dosage of alpha- and beta-blockers could be decreased.

Conclusions

We conclude that the withdrawal of an anxiolytic therapeutic regimen may generate sympathetic overdrive resulting in life-threatening paroxysmal malignant hypertension and secondary encephalopathy. We emphasize that pseudopheochromocytoma can be diagnosed only after exclusion of the secondary causes of hypertension. We highlight the importance of a psychopharmacological approach to this clinical entity.  相似文献   

7.

Background

Aberrant expression of microRNA-148a (miR-148a) has been reported in several types of malignancies. However, its expression and clinicopathological significance in hepatocellular carcinoma (HCC) has not been entirely clarified. Our objective was to investigate the clinicopathological contribution of the miR-148a expression in HCC formalin-fixed paraffin-embedded (FFPE) tissues.

Methods

Eighty-nine HCC and their para-cancerous liver tissues were recruited. Total mRNA including miRNA was isolated and miR-148a expression was determined by using real time RT-qPCR. Furthermore, the relationship between the miR-148a level and clinicopathological features was explored.

Results

Significantly lower miR-148a expression in HCC tissues was observed than that in adjacent noncancerous hepatic tissues. miR-148a expression was also correlated to clinical TNM stage, metastasis, status of capsular infiltration and numbers of tumor nodes.

Conclusions

Underexpression of miR-148a might be associated with HCC tumorigenesis and deterioration of HCC. miR-148a might act as a suppressor miRNA of HCC and it therefore has a potential role in prognosis of HCC patients.  相似文献   

8.
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10.

Background

Uterine sarcoma is an aggressive malignancy with a poor prognosis. This study aimed to determine the expression of CD146, P53, and Ki-67 in uterine sarcoma and to evaluate their prognostic significance.

Methods

We retrospectively analyzed the prognosis and clinicopathologic features of 68 patients with uterine sarcoma. Immunohistochemical analyses of CD146, P53, and Ki-67 were performed in tissue samples collected from these patients and their relationship with prognosis was investigated.

Results

The 5-year overall survival (OS) rate was 46 %. Endometrial stromal sarcoma (ESS) patients had a better prognosis than leiomyosarcoma (LMS) patients, with a 2-year survival rate of 82 %. The membrane and cytoplasm of tumor cells exhibited CD146 overexpression in 8 (32 %) ESS cases, which was less than the 25 (69.4 %) cases observed in LMS and 2 (28.6 %) in MMMT. CD146 overexpression in the membrane and cytoplasm of tumor cells was closely related to lymph node metastasis (P = 0.021) and Ki-67 overexpression (P = 0.0053); there was no significant correlation with age, tumor size, International Federation of Obstetrics and Gynecology stage, or P53 overexpression in LMS.

Conclusions

CD146, P53, and Ki-67 are overexpressed in uterine sarcoma. CD146 expression correlates with lymph node metastasis and is associated with poor OS in LMS; it may be a potential prognostic marker for LMS.  相似文献   

11.

Background

It has been demonstrated that urokinase-type plasminogen activator (uPA) is involved in tumor cell metastasis by degrading the extracellular matrix. However, there is little direct evidence of clinical uPA system expression in peritoneal metastatic tissues of gastric cancer. The objective of this study was to investigate uPA system expression in peritoneal tissues of peritoneal and nonperitoneal metastasis patients, and to explore the diagnostic value of the uPA system.

Methods

Expressions of uPA, uPAR, and PAI-1 were measured by semi-quantitative RT-PCR and ELISA. uPA activity was detected using a uPA activity kit.

Results

There was no significant difference in uPA, uPAR, and PAI-1 expression in two types of peritoneal tissue in seven patients with peritoneal metastasis. However, uPA, uPAR, and PAI-1 expressions in peritoneal metastatic lesions were significantly higher than those in normal peritoneal tissues of 24 nonperitoneal metastasis patients (P <0.05). Moreover, no statistical discrepancy of uPA activity was observed in various different tissues.

Conclusions

The expression of the uPA system positively correlates with peritoneal metastasis of gastric cancer. This expression difference in peritoneal or nonperitoneal metastasis patients may provide a reference for diagnosis of peritoneal metastasis.  相似文献   

12.

Objective

The influcence of cytomechanical forces in cellular migration, proliferation and differentation of mesenchymal stem cells (MSCs) is still poorly understood in detail.

Methods

Human MSCs were isolated and cultivated onto the surface of a 3 × 3 mm porcine collagen I/III carrier. After incubation, cell cultures were transfered to the different cutures systems: regular static tissue flasks (group I), spinner flasks (group II) and rotating wall vessels (group III). Following standard protocols cells were stimulated lineage specific towards the osteogenic and chondrogenic lines. To evaluate the effects of applied cytomechanical forces towards cellular differentiation distinct parameters were measured (morphology, antigen and antigen expression) after a total cultivation period of 21 days in vitro.

Results

Depending on the cultivation technique we found significant differences in both gen and protein expression.

Conclusion

Cytomechanical forces with rotational components strongly influence the osteogenic and chondrogenic differentiation.  相似文献   

13.

Background

Primary hepatocellular carcinoma (HCC) is one of the most common malignancies in the world. However, the molecular pathogenesis of HCC is not well-understood, and the prognosis for patients with HCC remains very poor.

Methods

To disclose detailed genetic mechanisms in hepatocellular carcinoma (HCC) with a view toward development of novel therapeutic targets, we analyzed expression profiles HCCs and their corresponding noncancerous tissues by using bioinformatics method.

Results

In this paper, we report the identification of genes whose expression has been altered and the changed bio-pathways during hepatocarcinogenesis. Hepatoma cells infect intracellular and intercellular signal transduction through Focal adhesion and cause abnormal expression of important intracellular signaling pathway. In addition, it is worth mentioning that some small molecules still restored to the state similar to normal cells, such as bambuterol and lovastatin. This member gene set would serve as a pool of lead gene targets for the identification and development of novel diagnostic and therapeutic biomarkers to greatly improve the clinical management of HCC patients with different risks of recurrence after curative partial hepatectomy.

Conclusions

The study has great significance for gene therapy and pharmacotherapy and provides a new treatment entry point and a potential new clinical drug for HCC patients.  相似文献   

14.
15.

Background

Hepatocellular carcinoma (HCC) is the fifth most common malignant tumor in men and the seventh in women and understanding the molecular mechanisms of HCC and establishing more effective therapies are critical and urgent issues. Our objective was to study the expression of ferroportin in hepatocellular carcinoma (HCC) tissue samples and the relationship between ferroportin expression and HCC characteristics.

Methods

Sixty HCC tissues and their corresponding para-cancer liver tissues (PCLT) were obtained from sixty HCC patients who had undergone hepatectomy in the Second Xiangya Hospital of Central South University. Ten normal liver tissue samples were also obtained as a control. Immunohistochemistry (IHC) was performed to analyze the ferroportin expression in HCC, and the relationship between ferroportin expression and HCC clinical pathological characteristics also was analyzed. For the evaluation of IHC results, the comprehensive scoring criteria were met according to the staining intensity and the number of positive staining cells. Western blotting was performed to detect the expression level of ferroportin in HCC cell lines.

Results

Ferroportin expression in HCC tissue was significantly lower compared to PCLT and normal liver tissue (P <0.05). Moreover, ferroportin expression was related to liver cancer cell de-differentiation, the severity degree in TNM staging, Edmondson-Steiner grading, intrahepatic metastasis and portal vein invasion. In addition, high expression of ferroportin was observed in normal human liver cell lines L02 and HL7702, whereas weak positive expression and even negative expression of ferroportin were observed in HCC cell lines FOCUS, MHCC-97H, HepG2 and SMMC-7721. Furthermore, among the four kinds of HCC cell lines, the expression level of ferroportin was the lowest in MHCC-97H cells.

Conclusions

Ferroportin expression level declines along with the progression of liver cancer, suggesting that the reduction of ferroportin may serve as an important marker for poor HCC prognosis and as a new therapeutic target.  相似文献   

16.

Background

Carcinoid tumors are slow growing neuroendocrine tumors which can originate from various sites within the body. A carcinoid tumor originating in the medulla spinalis has not previously been reported in the literature.

Case report

We report a case of a 33-year-old man, presenting with a five-month history of bilateral lower extremity pain, as well as paresthesia, and mild weakness in one lateral lower extremity. A lumbar laminectomy of L3 to L5 and en bloc resection of the tumor was performed. Postoperative histopathology and immunohistochemical analysis of the tumor were consistent with that of a carcinoid tumor. There were no clinical or radiological signs of tumor recurrence or metastasis at the patient’s two year postoperative follow-up.

Conclusions

During the differential diagnosis of medulla spinalis tumors, the possibility of a primary carcinoid tumor originating within the medulla spinalis should be considered. An accurate tumor classification is imperative to ensure that the most effective course of treatment is pursued.

Electronic supplementary material

The online version of this article (doi:10.1186/s40001-014-0071-7) contains supplementary material, which is available to authorized users.  相似文献   

17.

Objective

To determine the possible bioactive components of the ethanolic extract of leaves of Elaeocarpus serratus (E. serratus).

Methods

The present research was carried out by using GC-MS analysis, while mass spectra of the compounds found in the extract was matched with the National Institute of Standards and Technology and Wiley library.

Results

Thirty components from leaves of the above said plant were identified. The active principles with their retention time, molecular formula, molecular weight and concentration (%) in the ethanol extracts of leaf of E. serratus are obtained.

Conclusions

This is the first report of documentation of active constituents from leaves of E. serratus. The research reveals the potential of E. serratus leaves as a good source of bioactive compounds such as fatty acid esters, alcohols, hydrocarbons, aldehydes, alkenes, fatty acids and amides that justify the use of this plant for its various ailments by traditional practitioners.  相似文献   

18.

Background

Neoplasms of the parathyroid are common but parathyroid carcinoma is exceptionally rare. In contrast to most other malignant endocrine tumours that are usually less hormonally active, malignant parathyroid tumours are hyper functional. Malignant parathyroid tumours pose a diagnostic dilemma for the pathologist.

Objective

To study the clinicopathological profile of a case series of parathyroid neoplasms and determine features which facilitate a malignant diagnosis.

Methods

A retrospective analysis of seven cases of surgically treated parathyroid tumours over a three-year period at a single centre was done. Clinical, haematological, biochemical, and radiological data was accrued from medical records. The histopathology slides were reviewed along with the clinicopathological profile in an attempt to delineate markers of malignancy.

Results

Patients ranged from 30 to 58 years of age. Males and females were approximately equal. Weakness and bone pain were the commonest presenting symptoms. Over 50% had significant hypercalcaemia and all had elevated serum parathormone. Clinically apparent mass was seen in only one. All tumours were successfully localised using CT scan and MRI. Thick fibrous capsule and broad septal fibrosis was seen in both the carcinomas; these were thin in the adenomas. Mitotic counts of 1-3 per high power field (HPF), capsular invasion and nodal metastasis were noted in the malignant tumours.

Conclusion

Elevated serum calcium and parathormone values point to a parathyroid neoplasm. Current imaging modalities are successful in localising the tumour preoperatively. Markedly elevated serum calcium, broad fibrous bands, mitotic counts and capsular invasion are indicators of malignancy.Key Words: Parathyroid, Adenoma, Carcinoma  相似文献   

19.

Objective

Uncovering the dominant molecular deregulation among the multitude of pathways implicated in aggressive prostate cancer is essential to intelligently developing targeted therapies. Paradoxically, published prostate cancer gene expression signatures of poor prognosis share little overlap and thus do not reveal shared mechanisms. The authors hypothesize that, by analyzing gene signatures with quantitative models of protein–protein interactions, key pathways will be elucidated and shown to be shared.

Design

The authors statistically prioritized common interactors between established cancer genes and genes from each prostate cancer signature of poor prognosis independently via a previously validated single protein analysis of network (SPAN) methodology. Additionally, they computationally identified pathways among the aggregated interactors across signatures and validated them using a similarity metric and patient survival.

Measurement

Using an information-theoretic metric, the authors assessed the mechanistic similarity of the interactor signature. Its prognostic ability was assessed in an independent cohort of 198 patients with high-Gleason prostate cancer using Kaplan–Meier analysis.

Results

Of the 13 prostate cancer signatures that were evaluated, eight interacted significantly with established cancer genes (false discovery rate <5%) and generated a 42-gene interactor signature that showed the highest mechanistic similarity (p<0.0001). Via parameter-free unsupervised classification, the interactor signature dichotomized the independent prostate cancer cohort with a significant survival difference (p=0.009). Interpretation of the network not only recapitulated phosphatidylinositol-3 kinase/NF-κB signaling, but also highlighted less well established relevant pathways such as the Janus kinase 2 cascade.

Conclusions

SPAN methodolgy provides a robust means of abstracting disparate prostate cancer gene expression signatures into clinically useful, prioritized pathways as well as useful mechanistic pathways.  相似文献   

20.

Background

Bone fracture is one of the most common physical injuries in which gene expression and the microenvironment are reprogramed to facilitate the recovery process.

Methods

By specific siRNA transfection and MTT assay, we evaluated the effects of metastasis-associated gene 1 (MTA1) in osteoblast growth. To show the role of MTA1 in osteoblast under hypoxia conditions, by overexpressing and silencing MTA1 expression, we performed mineral deposition and alkaline phosphatase activity assay to observe the differentiation status of osteoblast cells. Real-time PCR and Western blot assays were adopted to detect the expression of certain target genes.

Results

Here, we reported that hypoxia-induced MTA1 expression through hypoxia-induced factor 1 alpha (HIF-1α) and stimulated the growth of osteoblast MC3T3 cells. Silencing of MTA1 through specific siRNA suppressed MC3T3 cell growth and elicited cell differentiation and induced alkaline phosphatase activation and the upregulation of bone morphogenetic protein-2 and osteocalcin.

Conclusions

We found that MTA1 was regulated by HIF-1α in hypoxia circumstance to suppress osteoblast differentiation. These findings provide new insights for bone fracture healing and new strategies to develop potential targets to promote fracture healing.

Electronic supplementary material

The online version of this article (doi:10.1186/s40001-015-0084-x) contains supplementary material, which is available to authorized users.  相似文献   

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