277 research outputs found
The degree structure of Weihrauch-reducibility
We answer a question by Vasco Brattka and Guido Gherardi by proving that the
Weihrauch-lattice is not a Brouwer algebra. The computable Weihrauch-lattice is
also not a Heyting algebra, but the continuous Weihrauch-lattice is. We further
investigate the existence of infinite infima and suprema, as well as embeddings
of the Medvedev-degrees into the Weihrauch-degrees
832-5 Multiple plaque ruptures are not frequent in acute coronary syndrome: A three-vessel intravascular ultrasound study
Rupture of Hepatocellular Carcinoma into the Biliary System with Resulting Bile Duct Thrombi: Report of Two Cases
We report two cases of hepatocellular carcinoma revealed by jaundice and the presence of free-floating tumoural fragments within the biliary system. Two men (one of 64 and one of 73) presented with isolated jaundice. The results from ultrasound, CT and MRI were suggestive of a cholangiocarcinoma. Surgical intervention demonstrated bile duct thrombi from the primary tumour causing obstructive jaundice
Identification of Genes Affecting the Toxicity of Anti-Cancer Drug Bortezomib by Genome-Wide Screening in S. pombe
Bortezomib/PS-341/Velcade, a proteasome inhibitor, is widely used to treat multiple myeloma. While several mechanisms of the cytotoxicity of the drug were proposed, the actual mechanism remains elusive. We aimed to identify genes affecting the cytotoxicity of Bortezomib in the fission yeast S.pombe as the drug inhibits this organism's cell division cycle like proteasome mutants. Among the 2815 genes screened (covering 56% of total ORFs), 19 genes, whose deletions induce strong synthetic lethality with Bortezomib, were identified. The products of the 19 genes included four ubiquitin enzymes and one nuclear proteasome factor, and 13 of them are conserved in humans. Our results will provide useful information for understanding the actions of Bortezomib within cells
Acute heart failure caused by a giant hepatocellular metastatic tumor of the right atrium
We present a symptomatic 40-year-old cirrhotic man who presented with sudden onsets of syncope. Echocardiography revealed right ventricular outflow track obstruction caused by a huge right atrial mass. The tumor was surgically excised under cardiopulmonary bypass. Although no primary cancerous lesion in the liver was detected, histopathology revealed that the mass was a metastatic hepatocellular carcinoma. The aim of this report is to show the value of urgent preoperative computed tomography and its contribution in the operative strategy. The importance of urgent surgical treatment with tricuspid valve sparing tumor resection is emphasized even though the prognosis for such patients is dismal. We also discuss the further management options of such rare case
Successful management of refractory pleural effusion due to systemic immunoglobulin light chain amyloidosis by vincristine adriamycin dexamethasone chemotherapy: a case report
<p>Abstract</p> <p>Introduction</p> <p>Refractory pleural effusion in systemic immunoglobulin light chain amyloidosis without cardiac decompensation is rarely reported and has a poor prognosis in general (a median survival of 1.6 months). Moreover, the optimum treatment for this condition is still undecided. This is the first report on the successful use of vincristine, adriamycin and dexamethasone chemotherapy for refractory pleural effusion due to systemic immunoglobulin light chain amyloidosis without cardiac decompensation.</p> <p>Case presentation</p> <p>We report the case of a 68-year old Japanese male with systemic immunoglobulin light chain amyloidosis presenting with bilateral pleural effusion (more severe on the right side) in the absence of cardiac decompensation that was refractory to diuretic therapy. The patient was admitted for fatigue, exertional dyspnea, and bilateral lower extremity edema. He had been receiving intermittent melphalan and prednisone chemotherapy for seven years. One month before admission, his dyspnea had got worse, and his chest radiograph showed bilateral pleural effusion; the pleural effusion was ascertained to be a transudate. The conventionally used therapeutic measures, including diuretics and thoracocentesis, failed to control pleural effusion. Administration of vincristine, adriamycin, and dexamethasone chemotherapy led to successful resolution of the effusion.</p> <p>Conclusion</p> <p>Treatment with vincristine, adriamycin, and dexamethasone chemotherapy was effective for the refractory pleural effusion in systemic immunoglobulin light chain amyloidosis without cardiac decompensation and appears to be associated with improvement in our patient's prognosis.</p
Combination therapy with PEG-IFN-α and 5-FU inhibits HepG2 tumour cell growth in nude mice by apoptosis of p53
When the tumour suppressor p53 is activated by DNA damage, it stimulates the transcription of its target genes, which then induce cell cycle arrest or apoptosis. Here, we examined the role p53 plays in the antitumour effect of combination treatment with pegylated interferon (PEG-IFN)-α and 5-fluorouracil (5-FU), which has been shown to effectively treat advanced hepatocellular carcinoma (HCC). Nude mice were injected subcutaneously with cultured HepG2 cells, in which p53 is functional. They were treated a week later with PEG-IFN and/or 5-FU for 7 weeks, after which we measured and examined their tumours. Combination groups showed significantly lower tumour volumes and higher tumour cell apoptosis than the other groups. Combination treatment and PEG-IFN monotherapy also significantly elevated the p53 protein and mRNA levels in the tumour but only combination treatment increased the degree of p53 phosphorylation at serine46 and induced p53-regulated apoptosis-inducing protein 1 (p53AIP1) expression. The antitumour effects of combination treatment is due in part to the elevation by PEG-IFN of p53 protein and mRNA expression and in part to the DNA damage that is generated by 5-FU, which induces p53 serine46 phosphorylation, which in turn upregulates p53AIP1 expression
BMP4の機能調節は糖尿病性腎症及びポドサイト障害の治療につながる
Podocyte injury has been proposed to play an important role in diabetic nephropathy; however, its pathological mechanism remains unclear. We have shown that bone morphogenetic protein 4 (BMP4) signaling leads to the glomerular changes characteristic of this disorder. To analyze the molecular mechanism of podocyte injury, the effect of BMP4 was investigated using streptozotocin (STZ)- induced, Bmp4 heterozygous knockout (Bmp4+/−) and podocyte-specific Bmp4 knockout mice. Mice with STZ-induced diabetes exhibited glomerular matrix hyperplasia and decreased numbers of podocyte nucleus-specific WT1-positive cells. The number of podocytes and proteinuria were improved in both diabetic Bmp4 knockout mouse models compared to the effects observed in the control mice. The effect of BMP4 overexpression on Bmp4-induced or podocyte-specific transgenic mice was examined. Tamoxifen-induced Bmp4-overexpressing mice exhibited mesangial matrix expansion and decreased numbers of WT1-positive cells. Podocyte-specific Bmp4-overexpressing mice displayed increased kidney BMP4 expression and mesangial matrix expansion but decreased nephrin expression and numbers of WT1-positive cells. Both lines of Bmp4-overexpressing mice exhibited increased albuminuria. In cultured podocytes, BMP4 increased phospho-p38 levels. BMP4 decreased nephrin expression but increased cleaved caspase-3 levels. p38 suppression inhibited caspase-3 activation. Apoptosis was confirmed in STZ-diabetic glomeruli and Bmp4-overexpressing mice. Bmp4 +/− mice with diabetes displayed reduced apoptosis. Based on these data, the BMP4 signaling pathway plays important roles in the development of both podocyte injury and mesangial matrix expansion in diabetic nephropathy
Oxidation of DJ-1 Induced by 6-Hydroxydopamine Decreasing Intracellular Glutathione
DJ-1, the causative gene of a familial form of Parkinson's disease (PD), has been reported to undergo preferential oxidation of the cysteine residue at position 106 (Cys-106) under oxidative stress; however, details of the molecular mechanisms are not well known. In the present study, mechanisms of DJ-1 oxidation induced by 6-hydroxydopamine (6-OHDA) were investigated by using SH-SY5Y cells. The treatment of these cells with 6-OHDA caused an obvious acidic spot sift of DJ-1 due to its oxidation. However, when catalase, which is an hydrogen peroxide (H2O2)-removing enzyme, was added during the treatment, it failed to prevent the oxidation induced by 6-OHDA, suggesting that electrophilic p-quinone formed from 6-OHDA, but not H2O2, was responsible for the DJ-1 oxidation. Benzoquinone, another electrophilic p-quinone, also induced DJ-1 oxidation. The intracellular glutathione (GSH) levels were significantly decreased by 6-OHDA, irrespective of the presence or absence of catalase. The inhibition of GSH synthesis by buthionine sulfoximine resulted in a decrease in GSH levels and enhancement of DJ-1 oxidation. The pretreatment of cells with N-acetyl-cysteine prevented the loss of intracellular GSH and subsequently DJ-1 oxidation induced by 6-OHDA. Collectively, these results suggest that electrophilic p-quinone formed from 6-OHDA induces DJ-1 oxidation by decreasing intracellular GSH
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