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1.
Z M Bhujwalla I Constantinidis J C Chatham J P Wehrle J D Glickson 《International journal of radiation oncology, biology, physics》1992,22(1):95-101
The metabolic consequences of increased glucose availability were examined in subcutaneous RIF-1 tumors in vivo, using 13C and 31P NMR spectroscopy. Significant increases in the levels of nucleotide triphosphates and phosphocreatine relative to low energy phosphates and in tumor pH were observed within 30 min following injection of 1 g/kg of glucose directly into the tumor. These changes did not occur following an equivalent intratumoral dose of the non-metabolizable sugar alcohol, mannitol. When [1-13C]-glucose was administered, [3-13C]-lactate and [3-13C]-alanine were the only labeled metabolites detected in the in vivo 13C NMR spectra during the period of bioenergetic improvement. Biochemical analysis revealed a substantial increase in tumor and plasma glucose concentration, but no increase in either tumor or plasma lactate, consistent with the absence of acidosis. Evaluation of the distribution of glucose in the tumor by quantitative autoradiography of [1-14C]-2-deoxyglucose administered with the glucose indicated that, on average, 7 mM of the added glucose distributed over the entire tumor within 10 min. The significant improvement in overall metabolic status of the tumors following glucose administration is attributed to the existence of substrate limited regions within the tumor. 相似文献
2.
Summary Three cases of the late adult form of neuronal ceroid lipofuscinosis (NCL) are reported. Two of these are siblings with a late clinical onset at ages 26 and 44 years. The third case, sporadic, has the oldest reported age for the onset of NCL, at 63 years and may be regarded as the first example of the presenile form of NCL. The clinical, morphological, histochemical, ultrastructural and genetic features of these three cases are discussed. The literature of the clinicopathological NCL cases with an onset at age of 25 and older is reviewed. The clinical and morphological differences between the late adult form and the presenile form of NCL as well as the difficulties in making the diagnosis are discussed.Supported by NIH Grant NS23717 相似文献
3.
Yamazaki K McGovern D Ragoussis J Paolucci M Butler H Jewell D Cardon L Takazoe M Tanaka T Ichimori T Saito S Sekine A Iida A Takahashi A Tsunoda T Lathrop M Nakamura Y 《Human molecular genetics》2005,14(22):3499-3506
The inflammatory bowel diseases (IBDs), Crohn's disease (CD) and ulcerative colitis, are chronic inflammatory disorders of the digestive tract. The pathogenesis of IBD is complicated, and it is widely accepted that immunologic, environmental and genetic components contribute to its etiology. To identify genetic susceptibility factors in CD, we performed a genome-wide association study in Japanese patients and controls using nearly 80,000 gene-based single nucleotide polymorphism (SNP) markers and investigated the haplotype structure of the candidate locus in Japanese and European patients. We identified highly significant associations (P = 1.71 x 10(-14) with odds ratio of 2.17) of SNPs and haplotypes within the TNFSF15 (the gene encoding tumor necrosis factor superfamily, member 15) genes in Japanese CD patients. The association was confirmed in the study of two European IBD cohorts. Interestingly, a core TNFSF15 haplotype showing association with increased risk to the disease was common in the two ethnic groups. Our results suggest that the genetic variations in the TNFSF15 gene contribute to the susceptibility to IBD in the Japanese and European populations. 相似文献
4.
Immunoreactive-vasopressin, -oxytocin, -dynorphin, -dynorphin-(1-8), -alpha-neo-endorphin and -[Met]enkephalin were, in each case, present in greater concentrations in dorsal as compared to ventral, and lumbo-sacral as compared to cervico-thoracic, spinal cord. These differences were significantly more pronounced for vasopressin and oxytocin than for the other peptides. Lesions of the hypothalamic paraventricular nucleus depleted levels of immunoreactive-vasopressin and -oxytocin throughout the cord whereas levels of the opioid peptides therein were unaffected. In contrast, destruction of either the supraoptic or suprachiasmatic nucleus failed to change the content of immunoreactive-vasopressin, -oxytocin or any of the opioid peptides in the cord. Dehydration for 3 days depressed levels of immunoreactive-vasopressin, -oxytocin and -dynorphin in the neurointermediate lobe of the pituitary. In distinction, the levels of these were not modified in the spinal cord. Further, treatment with the synthetic corticosteroid, dexamethasone, elevated levels of immunoreactive-vasopressin, -oxytocin and -dynorphin in the neurointermediate pituitary whereas these were unaffected in the spinal cord. It is concluded that vasopressin and oxytocin in the spinal cord are predominantly derived from the paraventricular nucleus, localized in dorsal lumbo-sacral regions of the cord and insensitive to endocrinological manipulations. These pools may, thus, be modulated differently from their counterparts in the neurohypophysis and have a differing role, possibly in the control of the primary processing, autonomic or motor junctions. Further, there is no evidence from these or our prior studies for a close interrelationship of spinal cord vasopressin with dynorphin-related peptides (or oxytocin with [Met]enkephalin), likewise in contrast to the neurohypophysis.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
5.
6.
Effects of endoscopic variceal treatment on oesophageal function: a prospective, randomized study 总被引:3,自引:0,他引:3
Viazis N Armonis A Vlachogiannakos J Rekoumis G Stefanidis G Papadimitriou N Manolakopoulos S Avgerinos A 《European journal of gastroenterology & hepatology》2002,14(3):263-269
AIM : Endoscopic methods are currently the most widely used techniques for the treatment of bleeding oesophageal varices (BOV). However, a number of complications may limit their usefulness. We conducted a prospective, randomized comparison of variceal ligation versus sclerotherapy in cirrhotics after the control of variceal haemorrhage to study the relative short-term risks of these two procedures with respect to oesophageal motility and gastro-oesophageal reflux. METHODS : Seventy-three patients with established cirrhosis and an episode of variceal bleeding controlled by one session of endoscopic therapy were randomized to treatment with sclerotherapy or ligation until variceal eradication. In 60 of these patients, oesophageal manometry and 24-h intra-oesophageal pH monitoring were performed at inclusion and 1 month after variceal eradication. RESULTS : After variceal eradication with sclerotherapy, peristaltic wave amplitude decreased from 76.2 +/- 14.7 mmHg to 61.6 +/- 17.7 mmHg (P = 0.0001), simultaneous contractions increased from 0% to 37.9% (P = 0.0008), and the percentage of time with pH < 4 increased from 1.60 +/- 0.25 to 4.91 +/- 1.16% in channel 1 (P = 0.0002) and from 1.82 +/- 0.27 to 5.69 +/- 1.37% in channel 2 (P = 0.0006). In contrast, the above parameters were not disturbed with ligation. CONCLUSION : Our data define the advantages of ligation over sclerotherapy with respect to post-treatment oesophageal dysmotility and associated gastro-oesophageal reflux. 相似文献
7.
I Venizelos I D Venizelos D Tamiolakis M Lambropoulou T Constantinidis G Petrakis G Alexiadis N Papadopoulos 《Revista española de enfermedades digestivas》2007,99(3):145-148
Composite neoplasms, carcinoid and adenocarcinoma have been reported to occur in several parts of the body, including the stomach, ampulla of Vater, large bowel, lung, and urinary bladder. Here we report a case of a 74-year-old male with a composite carcinoid-adenocarcinoma of the ileum associated with a transitional cell carcinoma of the bladder. The microscopical examination of the composite tumor showed an admixture of typical carcinoid tumor and moderately a differentiated adenocarcinoma. Immunohistochemically, the two components showed clear-cut differentiations. A review of the literature revealed that this is the first reported case of composite carcinoid-adenocarcinoma of the ileum associated with transitional cell carcinoma of the urinary bladder. 相似文献
8.
Dimitrios S. Karagiannakis Jiannis Vlachogiannakos Georgios Anastasiadis Irini Vafiadis-Zouboulis Spiros D. Ladas 《Hepatology International》2014,8(4):588-594
Background and purpose
Left ventricular diastolic dysfunction (LVDD) constitutes the prominent characteristic of cirrhotic cardiomyopathy, but its relevance on the clinical course of cirrhotic patients has not been clearly defined. The aim of the study was to evaluate the relationship of LVDD with the severity and etiology of liver disease and to investigate whether it affects the outcome of cirrhotic patients.Methods
Cardiac function of 45 cirrhotics was studied by a tissue Doppler imaging echocardiography. Diagnosis of LVDD was made according to the latest guidelines of the American Society of Echocardiography. All patients were followed up for a period of 2 years. Death or liver transplantation was the endpoint of the study.Results
LVDD was found in 17 (38 %) of 45 patients. Its presence was not found to be associated with the etiology and stage of cirrhosis, but its severity was directly correlated with the Child-Pugh score. At the end of follow-up, 14 patients had died; 9 had LVDD (9/17, 53 %) and 5 had not (5/28, 18 %). Patients who died at the beginning of observation period had a higher Child-Pugh and MELD score, higher BNP, lower albumin and more prolonged QTc. On Kaplan-Meier analysis, patients with LVDD had statistically significantly worse prognosis compared to those without (p = 0.013, log rank: 5.495). Low albumin values (p = 0.003) and presence of LVDD (p = 0.017) were independent predictive factors of mortality.Conclusions
LVDD is a common complication of cirrhosis. As its development seems to be related to a worse prognosis, patients with LVDD must be under a strict follow-up. 相似文献9.
10.
Test‐retest reliability of the default mode network in a multi‐centric fMRI study of healthy elderly: Effects of data‐driven physiological noise correction techniques 下载免费PDF全文
Rocco Marchitelli Ludovico Minati Moira Marizzoni Beatriz Bosch David Bartrés‐Faz Bernhard W. Müller Jens Wiltfang Ute Fiedler Luca Roccatagliata Agnese Picco Flavio Nobili Oliver Blin Stephanie Bombois Renaud Lopes Régis Bordet Julien Sein Jean‐Philippe Ranjeva Mira Didic Hélène Gros‐Dagnac Pierre Payoux Giada Zoccatelli Franco Alessandrini Alberto Beltramello Núria Bargalló Antonio Ferretti Massimo Caulo Marco Aiello Carlo Cavaliere Andrea Soricelli Lucilla Parnetti Roberto Tarducci Piero Floridi Magda Tsolaki Manos Constantinidis Antonios Drevelegas Paolo Maria Rossini Camillo Marra Peter Schönknecht Tilman Hensch Karl‐Titus Hoffmann Joost P. Kuijer Pieter Jelle Visser Frederik Barkhof Jorge Jovicich 《Human brain mapping》2016,37(6):2114-2132
Understanding how to reduce the influence of physiological noise in resting state fMRI data is important for the interpretation of functional brain connectivity. Limited data is currently available to assess the performance of physiological noise correction techniques, in particular when evaluating longitudinal changes in the default mode network (DMN) of healthy elderly participants. In this 3T harmonized multisite fMRI study, we investigated how different retrospective physiological noise correction (rPNC) methods influence the within‐site test‐retest reliability and the across‐site reproducibility consistency of DMN‐derived measurements across 13 MRI sites. Elderly participants were scanned twice at least a week apart (five participants per site). The rPNC methods were: none (NPC), Tissue‐based regression, PESTICA and FSL‐FIX. The DMN at the single subject level was robustly identified using ICA methods in all rPNC conditions. The methods significantly affected the mean z‐scores and, albeit less markedly, the cluster‐size in the DMN; in particular, FSL‐FIX tended to increase the DMN z‐scores compared to others. Within‐site test‐retest reliability was consistent across sites, with no differences across rPNC methods. The absolute percent errors were in the range of 5–11% for DMN z‐scores and cluster‐size reliability. DMN pattern overlap was in the range 60–65%. In particular, no rPNC method showed a significant reliability improvement relative to NPC. However, FSL‐FIX and Tissue‐based physiological correction methods showed both similar and significant improvements of reproducibility consistency across the consortium (ICC = 0.67) for the DMN z‐scores relative to NPC. Overall these findings support the use of rPNC methods like tissue‐based or FSL‐FIX to characterize multisite longitudinal changes of intrinsic functional connectivity. Hum Brain Mapp 37:2114–2132, 2016. © 2016 Wiley Periodicals, Inc. 相似文献