1,419 research outputs found

    Robot-assisted pancreatoduodenectomy with preservation of the vascular supply for autologous islet cell isolation and transplantation: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>For patients with chronic pancreatitis presenting with medically intractable abdominal pain, surgical intervention may be the only treatment option. However, extensive pancreatic resections are typically performed open and are associated with a substantial amount of postoperative pain, wound complications and long recovery time. Minimally invasive surgery offers an avenue to improve results; however, current limitations of laparoscopic surgery render its application in the setting of chronic pancreatitis technically demanding. Additionally, pancreatic resections are associated with a high incidence of diabetes. Transplantation of islets isolated from the resected pancreas portion offers a way to prevent post-surgical diabetes; however, preservation of the vascular supply during pancreatic resection, which determines islet cell viability, is technically difficult using current laparoscopic approaches. With recent advances in the surgical field, robotic surgery now provides a means to overcome these obstacles to achieve the end goals of pain relief and preserved endocrine function. We present the first report of a novel, minimally invasive robotic approach for resection of the pancreatic head that preserves vascular supply and enables the isolation of a high yield of viable islets for transplantation.</p> <p>Case presentation</p> <p>A 35-year old Caucasian woman presented with intractable chronic abdominal pain secondary to chronic pancreatitis, with a stricture of her main pancreatic duct at the level of the ampulla of Vater and distal dilatation. She was offered a robotic-assisted pylorus-preserving pancreatoduodenectomy and subsequent islet transplantation, to both provide pain relief and preserve insulin-secretory reserves.</p> <p>Conclusion</p> <p>We present a novel, minimally invasive robotic approach for resection of the pancreatic head with complete preservation of the vascular supply, minimal warm ischemia time (less than three minutes) and excellent islet recovery (134,727 islet equivalent). Our patient is currently pain-free with normal glycemic control. Robot-assisted pylorus-preserving pancreatoduodenectomy and autologous islet transplantation can be safely performed and has the potential to minimize operative traumas as well as to partially preserve endocrine function. Results from this case report suggest that this dual procedure should be considered as a treatment option for patients with chronic pancreatitis at earlier stages of the disease, before irreversible islet loss occurs.</p

    Lithium and GSK3-β promoter gene variants influence white matter microstructure in bipolar disorder

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    Lithium is the mainstay for the treatment of bipolar disorder (BD) and inhibits glycogen synthase kinase 3-β (GSK3-β). The less active GSK3-β promoter gene variants have been associated with less detrimental clinical features of BD. GSK3-β gene variants and lithium can influence brain gray matter structure in psychiatric conditions. Diffusion tensor imaging (DTI) measures of white matter (WM) integrity showed widespred disruption of WM structure in BD. In a sample of 70 patients affected by a major depressive episode in course of BD, we investigated the effect of ongoing long-term lithium treatment and GSK3-β promoter rs334558 polymorphism on WM microstructure, using DTI and tract-based spatial statistics with threshold-free cluster enhancement. We report that the less active GSK3-β rs334558*C gene-promoter variants, and the long-term administration of the GSK3-β inhibitor lithium, were associated with increases of DTI measures of axial diffusivity (AD) in several WM fiber tracts, including corpus callosum, forceps major, anterior and posterior cingulum bundle (bilaterally including its hippocampal part), left superior and inferior longitudinal fasciculus, left inferior fronto-occipital fasciculus, left posterior thalamic radiation, bilateral superior and posterior corona radiata, and bilateral corticospinal tract. AD reflects the integrity of axons and myelin sheaths. We suggest that GSK3-β inhibition and lithium could counteract the detrimental influences of BD on WM structure, with specific benefits resulting from effects on specific WM tracts contributing to the functional integrity of the brain and involving interhemispheric, limbic, and large frontal, parietal, and fronto-occipital connections

    Are we drawing the right conclusions from randomised placebo-controlled trials? A post-hoc analysis of data from a randomised controlled trial

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    <p>Abstract</p> <p>Background</p> <p>Assumptions underlying placebo controlled trials include that the placebo effect impacts on all study arms equally, and that treatment effects are additional to the placebo effect. However, these assumptions have recently been challenged, and different mechanisms may potentially be operating in the placebo and treatment arms. The objective of the current study was to explore the nature of placebo versus pharmacological effects by comparing predictors of the placebo response with predictors of the treatment response in a randomised, placebo-controlled trial of a phytotherapeutic combination for the treatment of menopausal symptoms. A substantial placebo response was observed but no significant difference in efficacy between the two arms.</p> <p>Methods</p> <p>A <it>post hoc </it>analysis was conducted on data from 93 participants who completed this previously published study. Variables at baseline were investigated as potential predictors of the response on any of the endpoints of flushing, overall menopausal symptoms and depression. Focused tests were conducted using hierarchical linear regression analyses. Based on these findings, analyses were conducted for both groups separately. These findings are discussed in relation to existing literature on placebo effects.</p> <p>Results</p> <p>Distinct differences in predictors were observed between the placebo and active groups. A significant difference was found for study entry anxiety, and Greene Climacteric Scale (GCS) scores, on all three endpoints. Attitude to menopause was found to differ significantly between the two groups for GCS scores. Examination of the individual arms found anxiety at study entry to predict placebo response on all three outcome measures individually. In contrast, <it>low </it>anxiety was significantly associated with improvement in the active treatment group. None of the variables found to predict the placebo response was relevant to the treatment arm.</p> <p>Conclusion</p> <p>This study was a <it>post hoc </it>analysis of predictors of the placebo versus treatment response. Whilst this study does not explore neurobiological mechanisms, these observations are consistent with the hypotheses that 'drug' effects and placebo effects are not necessarily additive, and that mutually exclusive mechanisms may be operating in the two arms. The need for more research in the area of mechanisms and mediators of placebo versus active responses is supported.</p> <p>Trial Registration</p> <p>International Clinical Trials Registry ISRCTN98972974.</p

    A phase II trial of bryostatin-1 administered by weekly 24-hour infusion in recurrent epithelial ovarian carcinoma

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    Bryostatin-1 is a macrocyclic lactone whose main mechanism of action is protein kinase C modulation. We investigated its activity as a weekly 24-h infusion in recurrent ovarian carcinoma. In all, 17 patients were recruited and 11 had chemotherapy-resistant disease as defined by disease progression within 4 months of last cytotoxic therapy. All were evaluable for toxicity and 14 for response. There were no disease responses and the main toxicity was myalgia

    Eukaryotic Initiation Factor 4E (eIF4E) and angiogenesis: prognostic markers for breast cancer

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    BACKGROUND: The overexpression of eukaryotic translation initiation factor 4E (eIF4E), a key regulator of protein synthesis, is involved in the malignant progression of human breast cancer. This study investigates the relationship between eIF4E and angiogenesis, as well as their prognostic impact in patients with human breast cancer. METHODS: Immunohistochemical staining was used to determine protein expression of eIF4E, vascular endothelial growth factor (VEGF), interleukin-8 (IL-8), and CD105 in a set of 122 formalin-fixed, paraffin-embedded primary breast cancer tissues. Expression of eIF4E in positive cells was characterized by cytoplasmic staining. Evaluation of VEGF and IL-8 in the same tissue established the angiogenic profiles, while CD105 was used as an indicator of microvessel density (MVD). RESULTS: A significant relationship was found between the level of eIF4E expression and histological grade (P = 0.016). VEGF, IL-8, and MVD were closely related to tumor grade (P = 0.003, P = 0.022, and P < 0.001, respectively) and clinical stage (P = 0.007, P = 0.048, and P < 0.001, respectively). Expression of eIF4E was also significantly correlated with VEGF (P = 0.007), IL-8 (P = 0.007), and MVD (P = 0.006). Patients overexpressing eIF4E had significantly worse overall (P = 0.01) and disease-free survival (P = 0.006). When eIF4E, histological grade, tumor stage, ER, PR, Her-2 status and the levels of VEGF, IL-8, MVD were included in a multivariate Cox regression analysis, eIF4E emerged as an independent prognostic factor for breast cancer (P = 0.001), along with stage (P = 0.005), node status (P = 0.046), and MVD (P = 0.004). CONCLUSION: These results suggest that higher eIF4E expression correlates with both angiogenesis and vascular invasion of cancer cells, and could therefore serve as a useful histological predictor for less favorable outcome in breast cancer patients, as well as represent a potential therapeutic target

    The Chop Gene Contains an Element for the Positive Regulation of the Mitochondrial Unfolded Protein Response

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    We have previously reported on the discovery of a mitochondrial specific unfolded protein response (mtUPR) in mammalian cells, in which the accumulation of unfolded protein within the mitochondrial matrix results in the transcriptional activation of nuclear genes encoding mitochondrial stress proteins such as chaperonin 60, chaperonin 10, mtDnaJ, and ClpP, but not those encoding stress proteins of the endoplasmic reticulum (ER) or the cytosol. Analysis of the chaperonin 60/10 bidirectional promoter showed that the CHOP element was required for the mtUPR and that the transcription of the chop gene is activated by mtUPR. In order to investigate the role of CHOP in the mtUPR, we carried out a deletion analysis of the chop promoter. This revealed that the transcriptional activation of the chop gene by mtUPR is through an AP-1 (activator protein-1) element. This site lies alongside an ERSE element through which chop transcription is activated in response to the ER stress response (erUPR). Thus CHOP can be induced separately in response to 2 different stress response pathways. We also discuss the potential signal pathway between mitochondria and the nucleus for the mtUPR

    A model for co-expression pattern analysis of genes implicated in angiogenesis and tumour cell invasion in cervical cancer

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    To date, numerous genes have been identified which are involved in both tumour neovascularisation (angiogenesis) and tumour cell invasion, and most of them are also expressed to some extent under normal physiological conditions. However, little is known about how these genes co-express in these settings. This study was undertaken to quantitate mRNA levels in normal and malignant cervical tissues of nine selected genes (VEGF121, VEGF165, VEGF189, VEGF-C, eIF-4E, b-FGF, TSP-2, MMP-2 and MMP-9) implicated in the above processes using real-time quantitative RT–PCR. In addition, the Spearman's rank correlation was used to determine their co-expression patterns. The transcript levels for the different VEGF-A splice variants (VEGF121, VEGF165, VEGF189) were at least 10-fold higher in the cancer cases, with the highest levels in the primary tumours demonstrating lympho-vascular space involvement. The lymphangiogenic factor VEGF-C and MMP-9 were upregulated 130- and 80-fold respectively in cervical cancers. The highest levels of VEGF-C mRNA were found in the lymph-node positive group. The transcript levels for b-FGF were similar in normal cervical tissue and early-stage cervical cancer, however, higher levels were found in the cervical cancers with advanced stage disease. Comparing gene transcript levels between recurrent and non-recurrent cervical cancer patients revealed significant differences (P=0.038) in transcript levels for the angiogenesis inhibitor TSP-2, with the highest levels in non-recurrent cases. Co-expression pattern analysis in normal cervical tissue revealed highly significant co-expressions (P<0.0001) between TSP-2 and most other genes analysed (VEGF121, VEGF165, VEGF-C, b-FGF and MMP-2). In cervical cancer, TSP-2 appears only to be highly co-expressed with MMP-2 (P<0.0001). In contrast to normal cervical tissue, we found a highly significant co-expression (P<0.0001) between MMP-9 and VEGF189 in cervical cancer. The combined application of real-time quantitative RT–PCR and Spearman's rank correlation identifies gene transcripts which are simultaneously co-expressed. Our results revealed a significant co-expression between the angiogenesis inhibitor TSP-2 and most other genes analysed in normal cervical tissue. In cervical cancer, we found a strong upregulation of VEGF-C and MMP-9 mRNA, with a highly significant co-expression between MMP-9 and VEGF189

    Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV

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    The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40 inverse picobarns of data collected in pp collisions at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection criteria covering a wide range of physics analysis needs have been examined. For all considered selections, the efficiency to reconstruct and identify a muon with a transverse momentum pT larger than a few GeV is above 95% over the whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4, while the probability to misidentify a hadron as a muon is well below 1%. The efficiency to trigger on single muons with pT above a few GeV is higher than 90% over the full eta range, and typically substantially better. The overall momentum scale is measured to a precision of 0.2% with muons from Z decays. The transverse momentum resolution varies from 1% to 6% depending on pseudorapidity for muons with pT below 100 GeV and, using cosmic rays, it is shown to be better than 10% in the central region up to pT = 1 TeV. Observed distributions of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO
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