Gastrointestinal Stromal Tumors: a Rare Neoplasm Presenting with Gastrointestinal Bleeding

Gastrointestinal stromal tumors (GIST) are rare tumors of the gastrointestinal (GI) tract that arise from primitive mesenchymal cells. GISTs occur throughout the GI tract but are usually located in the stomach and small intestine. GISTs are known with myoid, neural or mixed features of differentiation. Clinical findings are gastrointestinal bleeding, abdominal pain, and weight loss. GISTs express a heterogeneous clinical course not easily predicted. The histologic features that correlate best with development of recurrence and metastasis are mitotic activity, tumor size and the presence of tumor necrosis and most recently, mutation in the c-kit gene. Some authors specifically use the term GIST to refer to only those mesenchymal tumors that express CD117, whereas others believe that the diagnosis can be made in the absence of CD117 positivity based on clinical and morphologic features. Surgical resection remains the treatment of choice, since chemotherapy and radiation are ineffective. Long-term follow-up is imperative and recurrence rates are high. We report the case of a 60 years old female patient who presented with intermittent melena, chronic dyspepsia, and anemia. Upper digestive tract endoscopy showed a submucosal tumor, broad-based, centrally ulcerated, projection of >5 cm in the gastric corpus-antral wall as the cause of the upper gastrointestinal bleeding. Endoscopic biopsies were negative for neoplastic changes. After triple eradication therapy of Helicobacter pylori and treatment continued with proton pump inhibitor agent, the patient underwent distal gastrectomy with Billroth-I reconstruction. Histopatological studies on the surgical resection specimen revealed a GIST of smooth muscle with spindle cell, no evidence of mitotic activity but of uncertain biological behavior. One year after surgery the patient is was improved with no signs of residual Malignancy. However, metastases were found later in the liver in the next two year

The Terminator’s Vision of AI Warfare Is Now Reality

Forty years after The Terminator warned us about killer robots, AI-powered drones and autonomous weapons are being deployed in real-world conflicts. From Gaza to Ukraine, the dystopian future of machine warfare isn’t just science fiction anymore

Tissue-specific calibration of extracellular matrix material properties by transforming growth factor-beta and Runx2 in bone is required for hearing

Publisher version: http://www.nature.com/embor/journal/v11/n10/full/embor2010135.htmlDA - 20100917 IS - 1469-3178 (Electronic) IS - 1469-221X (Linking) LA - ENG PT - JOURNAL ARTICLEDA - 20100917 IS - 1469-3178 (Electronic) IS - 1469-221X (Linking) LA - ENG PT - JOURNAL ARTICLEDA - 20100917 IS - 1469-3178 (Electronic) IS - 1469-221X (Linking) LA - ENG PT - JOURNAL ARTICLEPhysical cues, such as extracellular matrix stiffness, direct cell differentiation and support tissue-specific function. Perturbation of these cues underlies diverse pathologies, including osteoarthritis, cardiovascular disease and cancer. However, the molecular mechanisms that establish tissue-specific material properties and link them to healthy tissue function are unknown. We show that Runx2, a key lineage-specific transcription factor, regulates the material properties of bone matrix through the same transforming growth factor-beta (TGFbeta)-responsive pathway that controls osteoblast differentiation. Deregulated TGFbeta or Runx2 function compromises the distinctly hard cochlear bone matrix and causes hearing loss, as seen in human cleidocranial dysplasia. In Runx2(+/-) mice, inhibition of TGFbeta signalling rescues both the material properties of the defective matrix, and hearing. This study elucidates the unknown cause of hearing loss in cleidocranial dysplasia, and demonstrates that a molecular pathway controlling cell differentiation also defines material properties of extracellular matrix. Furthermore, our results suggest that the careful regulation of these properties is essential for healthy tissue functio

The Terminator’s Vision of AI Warfare Is Now Reality

Forty years after The Terminator warned us about killer robots, AI-powered drones and autonomous weapons are being deployed in real-world conflicts. From Gaza to Ukraine, the dystopian future of machine warfare isn’t just science fiction anymore

Performance of Multi-Pixel Photon Counters for the T2K near detectors

We have developed a Multi-Pixel Photon Counter (MPPC) for the neutrino detectors of T2K experiment. About 64,000 MPPCs have been produced and tested in about a year. In order to characterize a large number of MPPCs, we have developed a system that simultaneously measures 64 MPPCs with various bias voltage and temperature. The performance of MPPCs are found to satisfy the requirement of T2K experiment. In this paper, we present the performance of 17,686 MPPCs measured at Kyoto University.Comment: 15 pages, 14 figure