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1.
Minerva Anestesiol ; 78(5): 527-33, 2012 May.
Article de Anglais | MEDLINE | ID: mdl-22534733

RÉSUMÉ

BACKGROUND: In this study we quantify the ability of dynamic cardiovascular parameters measured by the PulseCO™ algorithm of the LiDCO™plus monitor to predict the response to a fluid challenge in post-operative patients. METHODS: Surgical patients, admitted to the Intensive Care Unit from the operating theatre were monitored with the LiDCO™plus system. A number of static and dynamic cardiovascular measurements were recorded before and after a fluid challenge. Receiver Operator Characteristic (ROC) curve analysis was used to identify the baseline values, with optimum sensitivity and specificity, to predict responsiveness to a fluid challenge. RESULTS: Thirty-one patients were enrolled, and received protocol-based fluid challenges. Twelve (38%) responded by demonstrating an increase in stroke volume of >15%. Heart rate (HR) and central venous pressure (CVP) were not statistically different between responders and non-responders. Mean arterial pressure (mAP), systolic pressure variation (SPV), pulse pressure variation (PPV) and stroke volume variation (SVV) were statistically different between responders and non-responders. Parameters with a ROC area under the curve (AUC) significantly >0.5 included SPV 0.70 (0.52-0.88) P=0.046, PPV 0.87 (0.76-0.99) P<0.0002 and SVV 0.84 (0.71-0.96) P=0.0005. The best cut-off values (sensitivity and specificity) to predict fluid were SPV >9 mmHg (73%, 76%), PPV >13% (83%, 74%) and SVV >12.5% (75%, 83%). ROC analysis did not show the AUC to be significantly >0.5 for HR, mAP and CVP CONCLUSION: Dynamic indices measured by PulseCO™ (LiDCO) have a high sensitivity and specificity in predicting fluid responsiveness in sedated and mechanically ventilated patients. A cut-off value for PPV of 13% is the most sensitive and specific indicator of fluid responsiveness.


Sujet(s)
Pression sanguine , Traitement par apport liquidien , Hémodynamique , Monitorage physiologique , Soins postopératoires , Femelle , Humains , Mâle , Adulte d'âge moyen , Pronostic , Études prospectives
2.
Colorectal Dis ; 9(1): 3-14, 2007 Jan.
Article de Anglais | MEDLINE | ID: mdl-17181841

RÉSUMÉ

Tumour angiogenesis is a critical step in the growth, metastatic spread and regrowth of colorectal cancer. Angiogenesis specific to tumour is a complicated process, the mechanisms of which remain unclear. Metastasis of colorectal cancer may result from passive entry into the circulation secondary to the effect of angiogenic factors. The survival and growth of colorectal tumour and thus their metastases are dependent on the balance of endogenous angiogenic and anti-angiogenic factors such that the outcome favours increased angiogenesis. Angiogenesis has become an attractive target for anticancer drug development, based on its important roles in tumour growth, invasion and metastasis. Several growth factors have been identified that regulate angiogenesis in colorectal cancer; the most important of these are vascular endothelial growth factors (VEGF), and of the several angiogenic factors, VEGF expression at the deepest invasive site of tumour is the most statistically significant prognostic indicator in advanced colorectal carcinoma. In this review article, we provide an overview on angiogenic factors and their receptors, and discuss the role of newly identified tumour endothelial markers (TEMs) that are involved in tumour-associated angiogenesis in colorectal cancer.


Sujet(s)
Tumeurs colorectales/anatomopathologie , Néovascularisation pathologique/anatomopathologie , Marqueurs biologiques tumoraux , Humains , Protéines membranaires/analyse , Protéines des microfilaments , Protéines tumorales/analyse , Récepteurs de surface cellulaire/analyse , Récepteurs aux facteurs de croissance endothéliale vasculaire , Facteur de croissance endothéliale vasculaire de type A/physiologie
3.
J Hepatobiliary Pancreat Surg ; 12(4): 332-5, 2005.
Article de Anglais | MEDLINE | ID: mdl-16133704

RÉSUMÉ

Unlike in Japan, autoimmune pancreatitis is uncommon in the Western world, particularly in Europe. We report the first case of a Caucasian male with typical features of autoimmune pancreatitis in the UK. Recognizing autoimmune pancreatitis as a new clinical entity in Europe will change the management of many patients who have been labelled as having acute or chronic pancreatitis.


Sujet(s)
Maladies auto-immunes/diagnostic , Pancréatite/diagnostic , Sujet âgé , Humains , Mâle ,
4.
Biochem Biophys Res Commun ; 334(1): 231-8, 2005 Aug 19.
Article de Anglais | MEDLINE | ID: mdl-15993844

RÉSUMÉ

BACKGROUND AND AIMS: Tumour endothelial marker-8 (TEM-8) has been found to be selectively up regulated in tumour-associated endothelial cells, it is implicated in tumour specific angiogenesis, but its mechanism in angiogenesis is not defined. METHODS: A ribozyme transgene (TEM-8) was cloned into a suitable mammalian expression vector (pc DNA 3.1-GFP-NT) and transfected into HECV cells. Various domains of TEM-8 were designed and cloned into pEF6/V5-His TOPO TA vector and transfected into Chinese Hamster ovarian cells (CHO), which do not form tubules and do not express TEM-8 in general (CHO(vW), CHO(TM), CHO(vW/TM), CHO(AE), CHO(AC), CHO(IC), and CHO(FL) domains, respectively). The effect of TEM-8 knocked out HECV cells was tested (by angiogenesis and migration assays), and the effect of each cleavage domain of TEM-8 was tested by microtubule formation assay. RESULTS: TEM-8 stable transfectants (HECV(DeltaTEM8a)) manifested a complete loss of TEM-8 gene expression at mRNA and protein levels. In contrast, control GFP plasmid (HECV(pControl)) and wild-type HECV cells (HECV(WT)) had similar levels of TEM-8 expression. TEM-8 transfected cell (HECV(DeltaTEM8a)) significantly decreased the micro-vessels formation compared with controls (HECV(pControl)) (mean+/-SE, 20.3+/-4.03 microm; p=0.0086 vs. control 39.5+/-10.1 microm), and migration (38.52+/-2.17; p<0.05 vs. control 80.23+/-3.19), and micro-vessel formation of HECV(DeltaTEM8a) cell was also reduced compared with wild-type (HECV(WT)) (mean+/-SE, 20.3+/-4.03 microm; p=0.0078 vs. wild-type 42.5+/-9.1 microm) and migration (38.52+/-2.17microm; p<0.05 vs. wild-type 82.4+/-4.45 microm). vW together with transmembrane domains of TEM-8 (CHO(vW/TM)) and full-length CHO(FL) showed formation of tubule-like structure in CHO cells, whereas the other domains showed no effect. CONCLUSION: Targeting the TEM-8 gene by way of a hammerhead ribozyme knocks out TEM-8 cells, and is an effective way to reduce the micro-vessel formation or migration potential in tumour-associated endothelial cell through its vW domain. These results suggest that the vW domain together with the transmembrane domain of TEM-8 may play an important biological role in TEM-8 related tubule formation.


Sujet(s)
Cellules endothéliales/cytologie , Cellules endothéliales/physiologie , Microcirculation/croissance et développement , Microcirculation/métabolisme , Néovascularisation physiologique/physiologie , Récepteurs de surface cellulaire/composition chimique , Récepteurs de surface cellulaire/métabolisme , Lignée cellulaire , Mouvement cellulaire/physiologie , Humains , Protéines membranaires , Microcirculation/cytologie , Protéines des microfilaments , Microtubules/métabolisme , Microtubules/ultrastructure , Protéines tumorales , Structure tertiaire des protéines , Protéines recombinantes/composition chimique , Protéines recombinantes/métabolisme , Relation structure-activité
5.
World J Gastroenterol ; 11(9): 1283-6, 2005 Mar 07.
Article de Anglais | MEDLINE | ID: mdl-15761964

RÉSUMÉ

AIM: Tumor endothelial markers (TEMs) are a newly discovered family of endothelial markers associated with tumor specific angiogenesis. This study sought to examine the levels of expression (qualitatively and quantitatively) for TEMs in human colon cancer. METHODS: Human colorectal cancer tissues (n = 48) and normal background tissues (n = 31) were obtained after surgery. RNA was extracted from frozen sections for gene amplification. The expression of TEMs (TEM-1 to TEM-8) was assessed using RT-PCR and their transcript levels were determined using real-time-quantitative PCR (Q-RT-PCR). RESULTS: TEM-1 (P = 0.01), TEM-7 (P = 0.04), TEM-7R (P = 0.03), TEM-8 (P = 0.001) significantly raised in colon cancer tissues compared with the levels detected in normal background tissues. The expressions of TEM-2 and TEM-6 were found to be not significantly different between tumor tissues and normal tissues (P > 0.05). Patients who had cancer penetrating into and through the muscularis propria of the bowel wall and developed nodal involvement (Dukes C) exhibited significantly higher levels of TEM -8 compared to patients who were node negative (P < 0.05). TEM-7 and TEM-7R showed high level of transcripts in Dukes C, but they were not statistically significant. CONCLUSION: The level of the expression of TEM-1, TEM-7, TEM-7R and TEM-8 (but not TEM-2 and TEM-6) were associated with both nodal involvement and disease progression, and may therefore, have a prognostic value in colorectal cancer.


Sujet(s)
Marqueurs biologiques tumoraux/génétique , Tumeurs colorectales/génétique , Tumeurs colorectales/anatomopathologie , Endothélium vasculaire/physiologie , Néovascularisation pathologique/génétique , Néovascularisation pathologique/anatomopathologie , Antigènes CD , Antigènes néoplasiques , Tumeurs colorectales/vascularisation , Régulation de l'expression des gènes tumoraux , Dépistage génétique , Humains , Protéines membranaires/génétique , Protéines des microfilaments , Protéines tumorales/génétique , Stadification tumorale , Pronostic , ARN messager/analyse , Récepteurs de surface cellulaire/génétique , RT-PCR
6.
Eur J Surg Oncol ; 30(9): 948-53, 2004 Nov.
Article de Anglais | MEDLINE | ID: mdl-15498639

RÉSUMÉ

BACKGROUND AND AIMS: Tumour endothelial marker-8 (TEM-8) is endothelial cell surface marker that may be specific to tumour endothelial cells. This study examined the role of TEM-8 in human colon cancer and its correlation with tumour prognosis. METHODOLOGY: Specimens of colorectal tissue (normal and cancer) were stained immunohistochemically with an anti-TEM-8 antibody, newly developed in our laboratory, and with anti-vonWillebrand Factor antibody. RNA was extracted from frozen sections for gene amplification. The anti-TEM-8 antibody specificity tested by using slot blotting with irrelevant antibody, and western blotting with different cell lines. The expression of TEM-8 was assessed using RT-PCR, and the level of TEM-8 was quantified using real-time-quantitative PCR (Q-RT-PCR). RESULTS: TEM-8 staining was primarily seen in endothelial cells. TEM-8 identified more micro-vessels in colon tumour tissue, than in normal colon tissues, (p=0.002). Whereas, fewer vessels were stained positive for TEM-8 in normal tissues stained positive for vonWillebrand Factor (factor-8), (p=0.008). Malignant cells in tumour tissues were found to be stained strongly positive for TEM-8 compared with the epithelial cells in normal colon tissues. The level of TEM-8 expression was significantly higher in the tumour tissues compared to the normal colon mucosa (p=0.001). TEM-8 mRNA expression was also found to be more elevated in patients with advanced tumour, Dukes C (Dukes A vs. Dukes C, p=0.01). CONCLUSION: TEM-8 is a marker that identifies tumour associated micro-vessels in colon cancer. The levels of expression of TEM-8 in invasive colon cancer are linked to disease progression. This suggests that TEM-8 has significant prognostic and therapeutic values in colon cancer.


Sujet(s)
Marqueurs biologiques tumoraux/métabolisme , Tumeurs colorectales/métabolisme , Récepteurs de surface cellulaire/métabolisme , Technique de Western , Loi du khi-deux , Évolution de la maladie , Humains , Immunohistochimie , Protéines membranaires , Protéines des microfilaments , Protéines tumorales , Néovascularisation pathologique/métabolisme , ARN tumoral/métabolisme , RT-PCR
7.
Neuroscience ; 123(1): 187-200, 2004.
Article de Anglais | MEDLINE | ID: mdl-14667453

RÉSUMÉ

In Parkinson's disease the neurones of the subthalamic nucleus show increased synchrony and oscillatory burst discharge, thought to reflect a breakdown of parallel processing in basal ganglia circuitry. To understand better the mechanisms underlying this transition, we sought to mimic this change in firing pattern within sagittal slices of rat midbrain. The firing patterns of up to four simultaneously extracellularly recorded subthalamic nucleus (STN) neurones were analysed using burst and oscillation detection programs, and correlated activity between pairs of neurones assessed. In control conditions all but 11 of 488 (2%) neurones fired in a predominantly tonic pattern (with mean oscillation frequency >3 Hz), with no significantly cross-correlated activity in any of 393 pairs of neurones. The glutamate antagonists DL-2-amino-phosphonopentanoic acid (APV), 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) and 6-methyl-2-(phenylethynyl)pyridine (MPEP) did not change the firing rate or pattern of these cells, providing no evidence for a role of glutamatergic collaterals within the STN under these conditions. The GABA(A) receptor antagonist bicuculline and GABA(B) receptor antagonist (2S)-3-[[(1S)-1-(3,4-dichlorophenyl)ethyl]amino-2-hydroxypropyl]phenylmethyl phosphinic acid (CGP 55845) were also without effect on firing rate or pattern in these cells, suggesting that there was no active input from other GABAergic basal ganglia nuclei in this slice. The dopamine receptor antagonist haloperidol caused no significant change to firing rate or pattern of firing in these cells, suggesting that there was no active dopaminergic input in this slice. Excitations of STN neurones by muscarine, (+)-1-aminocyclopentane-trans-1,3-dicarboxylic acid (ACPD), N-methyl-D-aspartic acid (NMDA) or dopamine were all unaccompanied by a change in firing pattern or any significant correlated activity between STN neurone pairs. Burst firing could be induced in STN neurones with either the potassium channel blocker tetraethylammonium (TEA; 10 mM; in 100/138 [72%] of cells) or with a combination of NMDA and the calcium-activated potassium channel blocker apamin (in 101/216 [47%] of cells). Burst firing in TEA was unchanged by CNOX and APV, MPEP, CGP55845, haloperidol, dopamine, and ACPD, although muscarine produced a significant increase in oscillation frequency. Burst firing in NMDA and apamin was unchanged by CNQX and APV, dopamine, muscarine and ACPD, although bicuculline caused a significant increase in oscillation frequency. Such burst firing was not accompanied by synchrony in any condition, either alone, or during application of excitatory agents or glutamate or GABA antagonists. As the bursting seen here was unaccompanied by the synchronous activity that has often been observed (pathologically) in vivo, it probably reflects solely intrinsic STN neuronal properties, rather than network activity. No functional role was found for glutamatergic collaterals within the STN, either when cells are firing tonically or burst firing. The circuitry needed to produce synchrony in the STN is most likely not intrinsic to the STN itself, but requires connections with other basal ganglia nuclei, and/or the cortex, which are not present in this preparation.


Sujet(s)
Potentiels d'action/physiologie , Horloges biologiques/physiologie , Neurones/physiologie , Noyau subthalamique/physiologie , Potentiels d'action/effets des médicaments et des substances chimiques , Animaux , Horloges biologiques/effets des médicaments et des substances chimiques , Encéphale/effets des médicaments et des substances chimiques , Encéphale/physiologie , Techniques in vitro , Mâle , N-Méthyl-aspartate/pharmacologie , Réseau nerveux/effets des médicaments et des substances chimiques , Réseau nerveux/physiologie , Neurones/effets des médicaments et des substances chimiques , Rats , Rat Wistar , Noyau subthalamique/effets des médicaments et des substances chimiques , Tétraéthyl-ammonium/pharmacologie
8.
Neuroscience ; 116(1): 157-66, 2003.
Article de Anglais | MEDLINE | ID: mdl-12535949

RÉSUMÉ

Recent anatomical and physiological studies have pointed to a functional innervation of the subthalamic nucleus by dopamine. This nucleus has a pivotal role in basal ganglia function and voluntary movement control and the possibility that dopamine, and dopaminergic medication used in Parkinson's disease, might directly influence its activity is of considerable interest. We have evaluated electrophysiologically the action and pharmacology of dopamine on single subthalamic neurones in rat brain slices. Dopamine increased firing rate to up to a mean of 60% in 98% of the 261 neurones tested when examined using extracellular single-unit recording. This excitation was unaffected by the GABA antagonist picrotoxin, and the glutamate receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione, and persisted in a low Ca(2+)/raised Mg(2+) solution, indicative of a direct action, independent of synaptic transmission. Of the 33 cells examined using whole patch-clamp recording, only 13 showed measurable increases in firing rate and/or depolarisations in response to dopamine. Dopamine-responsive cells displayed significantly greater access resistance, suggesting that an unidentified cytoplamic constituent, removed by whole-cell dialysis, was required for the response. Using extracellular recording, the D2-like dopamine receptor agonists quinpirole and bromocryptine, but not the D1-like receptor agonist 1-phenyl-2,3,4,5-tetrahydro-(1H)-3-benzazepine-7,8-diol, also consistently caused an excitation. This was mimicked by the catecholamine releaser amphetamine in 60% of cells tested. However, the dopamine excitation was not significantly reduced either by the D1-like receptor antagonist 7-chloro8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine or the D2-like receptor antagonists (-)-sulpiride, eticlopride and (+)-butaclamol, and the quinpirole excitation was also unaffected by (-)-sulpiride. In contrast, (-)-sulpiride, eticlopride and (+)-butaclamol all abolished the D2-like receptor-mediated inhibition by dopamine of substantia nigra pars compacta neurones. The alpha-adrenoceptor antagonist phentolamine was a weak antagonist of dopamine excitations, but not of those caused by quinpirole. Dopamine excitations also showed weak sensitivity to the 5-HT(2) antagonist ritanserin, but were unaffected by the alpha(1)-adrenoceptor antagonist prazocin and the beta-adrenoceptor antagonist propranolol. The pharmacology of this dopamine excitation is inconsistent with an action on any known catecholamine receptor. However, the effect of amphetamine indicates that an unidentified monamine--possibly dopamine--can be released within the subthalamic nucleus to cause an excitation. The anomalies of its pharmacological characterisation do not strongly support a physiologically relevant direct action of dopamine in the rat subthalamic nucleus.


Sujet(s)
Agonistes de la dopamine/pharmacologie , Antagonistes de la dopamine/pharmacologie , Dopamine/physiologie , Neurones/physiologie , Récepteurs dopaminergiques/physiologie , Noyau subthalamique/physiologie , Amfétamine/pharmacologie , Animaux , Dopamine/pharmacologie , Inhibiteurs de la capture de la dopamine/pharmacologie , Relation dose-effet des médicaments , Électrophysiologie , Mâle , Neurones/effets des médicaments et des substances chimiques , Rats , Rat Wistar , Noyau subthalamique/effets des médicaments et des substances chimiques
10.
Br J Surg ; 88(5): 662-8, 2001 May.
Article de Anglais | MEDLINE | ID: mdl-11350436

RÉSUMÉ

BACKGROUND: Chemotherapy for pancreatic cancer offers small survival benefits and considerable side-effects. Unsaturated fatty acids have an antitumour effect in experimental studies; in phase II studies few side-effects were seen. METHODS: In this group-sequential, open-label, randomized study, 278 patients with a diagnosis of inoperable pancreatic cancer were treated with either oral (700 mg daily for 15 days), low-dose (0.28 g/kg) or high-dose (0.84 g/kg) intravenous lithium gamolenate (LiGLA). The primary endpoint was survival time from randomization using Kaplan-Meier estimates. RESULTS: Median survival after oral and low-dose intravenous treatment was 129 and 121 days respectively. Median survival after high-dose intravenous treatment was 94 days. A good Karnofsky score and the absence of metastases were associated with increased survival. Haemolysis, a marker of rapid infusion, was associated with a median survival time of 249 days in the low-dose intravenous group. CONCLUSION: Oral or low-dose intravenous LiGLA led to survival times similar to those of other treatments for pancreatic cancer although one subgroup (low-dose intravenous LiGLA with haemolysis) had longer survival. High-dose intravenous treatment appeared to have an adverse effect. Systemic treatment with LiGLA cannot be recommended for the treatment of pancreatic cancer.


Sujet(s)
Adénocarcinome/traitement médicamenteux , Antinéoplasiques/administration et posologie , Tumeurs du pancréas/traitement médicamenteux , Administration par voie orale , Adolescent , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Relation dose-effet des médicaments , Acides gras insaturés/administration et posologie , Humains , Perfusions veineuses , Adulte d'âge moyen , Analyse de survie , Gammaglobulines
11.
HPB Surg ; 11(4): 207-15; discussion 215-6, 1999.
Article de Anglais | MEDLINE | ID: mdl-10468111

RÉSUMÉ

BACKGROUND: It has been suggested that antioxidant deficiency may play a role in the pathogenesis of chronic pancreatitis. The aim of this review was to analyse the evidence for this relationship and to consider the role of antioxidant supplementation in the treatment of chronic pancreatitis. METHODS: Medline review of all English language publications for the years 1966-1998. RESULTS AND CONCLUSIONS: There is evidence that patients with chronic pancreatitis have enhanced levels of free radical production, cytochrome P450 induction and antioxidant deficiencies, in particular selenium. The limited published literature in this field suggests that dietary antioxidant supplementation may ameliorate the pain associated with chronic pancreatitis, diminish the frequency of acute exacerbations and reduce the requirement for pancreatic surgery. These findings await confirmation by a large prospective placebo-controlled study.


Sujet(s)
Antioxydants/usage thérapeutique , Pancréatite/traitement médicamenteux , Pancréatite/étiologie , Sélénium/administration et posologie , Sélénium/déficit , Maladie chronique , Essais cliniques comme sujet , Femelle , Humains , Mâle , Pancréatite/physiopathologie , Appréciation des risques , Résultat thérapeutique
12.
Am J Gastroenterol ; 94(8): 2135-40, 1999 Aug.
Article de Anglais | MEDLINE | ID: mdl-10445540

RÉSUMÉ

OBJECTIVE: It has been suggested that patients with chronic pancreatitis have antioxidant deficiencies. It is unclear whether these antioxidant deficiencies also occur in patients with recurrent acute pancreatitis and whether this condition represents an intermediate state between normality and chronic pancreatitis. The aim of this study was to determine the antioxidant profiles of patients with pancreatitis (recurrent acute and chronic) and to compare their profiles with a control population. METHODS: The antioxidant profiles of patients with chronic pancreatitis (n = 27) and recurrent acute pancreatitis (n = 11) were determined and compared with the antioxidant profiles of control subjects (n = 19). The following parameters were measured in blood: trace elements (selenium, copper, zinc), vitamins A and E, and carotenoids (alpha-carotene, beta-carotene, xanthine, beta-cryptoxanthine, lycopene). RESULTS: Patients with chronic pancreatitis had significantly lower plasma concentrations of selenium, vitamin A, vitamin E, beta-carotene, xanthine, beta-cryptoxanthine, and lycopene compared with both control subjects and patients with recurrent acute pancreatitis (p < 0.05). There were no significant differences between the antioxidant profiles of patients with chronic pancreatitis due to alcohol excess and patients with idiopathic chronic pancreatitis, or between the antioxidant profiles of patients with recurrent acute pancreatitis and control subjects. CONCLUSIONS: Patients with chronic pancreatitis had evidence of multiple antioxidant deficiencies. The antioxidant profiles of patients with recurrent acute pancreatitis did not differ from those of control subjects, discounting the hypothesis that recurrent acute pancreatitis represents an intermediate state between normality and chronic pancreatitis.


Sujet(s)
Antioxydants/analyse , Pancréatite/diagnostic , Maladie aigüe , Adulte , Sujet âgé , Maladie chronique , Femelle , Humains , Mâle , Adulte d'âge moyen , Pancréatite/sang , Récidive , Valeurs de référence , Facteurs de risque
13.
Clin Exp Metastasis ; 15(6): 593-602, 1997 Nov.
Article de Anglais | MEDLINE | ID: mdl-9344043

RÉSUMÉ

Desmosomes are key structures in cell-cell adhesion. In this study we examined the effect of n-6 essential fatty acids on the expression of desmoglein (Dsg), desmosomal cadherin and the formation of desmosomes in E-cadherin negative human breast, colon and lung cancer cells and melanoma cells. Electron microscopy revealed that cells cultured with gamma linolenic acid (GLA) showed increased cell-cell adhesion together with an increase in the formation of desmoglein-containing desmosomes. Western blotting studies of cellular proteins demonstrated that, following culture with fatty acids, Dsg expression was modified, with the greatest increase seen after GLA treatment. Other fatty acids increased Dsg expression, but to a lesser extent. It is concluded that GLA regulates desmosome-mediated cell-cell adhesion in human cancer cells, particularly in cells without E-cadherin.


Sujet(s)
Cadhérines/métabolisme , Adhérence cellulaire , Protéines du cytosquelette/métabolisme , Desmosomes/métabolisme , Tumeurs/métabolisme , Acide gamma linolénique/pharmacologie , Mouvement cellulaire/effets des médicaments et des substances chimiques , Desmogléines , Desmoplakines , Humains , Tumeurs/anatomopathologie , Cellules cancéreuses en culture
14.
HPB Surg ; 10(3): 129-42, 1997.
Article de Anglais | MEDLINE | ID: mdl-9174857

RÉSUMÉ

Patients with obstructive jaundice have an increased perioperative complication rate. Sepsis, bleeding, wound problems, renal and liver malfunction are all seen in these patients. Assessment of immune function has been an active research area in these patients. This review will examine various aspects of immune functions in obstructive jaundice, discuss the recent research results and controversies and then go on to discuss the relevant mediators of immune function and some possible implications for treatment.


Sujet(s)
Cholestase/immunologie , Animaux , Cholestase/traitement médicamenteux , Cytokines/physiologie , Chiens , Endotoxines/antagonistes et inhibiteurs , Humains , Lactulose/pharmacologie , Lactulose/usage thérapeutique , Lymphocytes/immunologie , Système phagocytaire mononucléé/immunologie , Granulocytes neutrophiles/immunologie , Granulocytes neutrophiles/métabolisme , Palmitates/usage thérapeutique , Phagocytose , Polymyxine B/pharmacologie , Polymyxine B/usage thérapeutique , Rats , Superoxydes/métabolisme
15.
Cancer Invest ; 15(6): 513-21, 1997.
Article de Anglais | MEDLINE | ID: mdl-9412656

RÉSUMÉ

The c-met proto-oncogene product is a receptor tyrosine kinase that mediates the effects of the multifunctional cytokine hepatocyte growth factor/scatter factor (HGF/SF). We have studied the expression of both the c-met receptor and HGF/SF at both the protein and message level in colorectal cancer tissues of varying disease stage. All of the tumors displayed an overexpression of the c-met mRNA compared to their normal tissue counterparts while 16 of 21 tissues (75%) displayed up-regulation of c-met protein. No HGF/SF mRNA or protein could be detected in either tissue type. Viable tumor cells extracted from cancer tissue exhibited increased motility in response to HGF/SF stimulation demonstrating that c-met was functionally active. No correlation between expression of c-met and tumor stage or degree of differentiation was observed. HGF/SF is known to be a potent stimulator of tumor cell motility and invasion, two cellular properties essential for the metastatic development of cancers. The overexpression of the HGF/SF receptor in colorectal cancers may result in an increased sensitivity to HGF/SF, which may confer an enhanced metastatic potential to the cancer cells within the tumor body.


Sujet(s)
Tumeurs colorectales/métabolisme , Protéines proto-oncogènes c-met/métabolisme , Technique de Northern , Technique de Western , Tumeurs colorectales/anatomopathologie , Humains , Immunohistochimie , Ligands , Stadification tumorale , Proto-oncogène Mas , Protéines proto-oncogènes c-met/biosynthèse , ARN messager/analyse
16.
Br J Surg ; 83(5): 659-64, 1996 May.
Article de Anglais | MEDLINE | ID: mdl-8689213

RÉSUMÉ

The effect of n-6 fatty acids, particularly gamma-linolenic acid (GLA), on the oxidase response and neutrophil priming by tumour necrosis factor alpha and interleukin 8 was studied in both normal volunteers and patients with obstructive jaundice. GLA inhibited the neutrophil respiratory burst at concentrations higher than 50 mummol/l, but abolished cytokine priming at concentrations as low as 1 mummol/l. Inhibition was not the result of either cytotoxicity to the neutrophils or alteration in cytosolic free calcium homoeostasis. It is concluded that GLA is a potential inhibitor of neutrophil priming by cytokines and of the oxidative response.


Sujet(s)
Interleukine-8/métabolisme , Granulocytes neutrophiles/métabolisme , Stimulation du métabolisme oxydatif/effets des médicaments et des substances chimiques , Facteur de nécrose tumorale alpha/métabolisme , Acide gamma linolénique/pharmacologie , Sujet âgé , Sujet âgé de 80 ans ou plus , Calcium/métabolisme , Cholestase/métabolisme , Humains , Adulte d'âge moyen
17.
J Gastroenterol Hepatol ; 11(1): 7-13, 1996 Jan.
Article de Anglais | MEDLINE | ID: mdl-8672745

RÉSUMÉ

Some monocytic cytokines are important immune regulators. We have investigated cytokine production by monocytes and the blood levels of IL-1 beta, IL-6, TNF alpha, and TGF beta, in patients with obstructive jaundice. The supernatant from LPS stimulated monocytes from jaundiced patients released significantly increased quantities of TNF alpha by both bioassay and radioimmunoassay (RIA) (12.4 +/- 2.5 fmol/mL and 32.6 +/- 8.3 fmol/mL, respectively, for jaundice, compared with 1.6 +/- 0.3 fmol/mL and 2.4 +/- 0.5 fmol/mL respectively for controls, and also of IL-6 (54.8 +/- 5.0 fmol/mL in jaundice compared with 35.6 +/- 5.0 fmol/mL for controls). The production of IL-1 beta and TGF beta by stimulated monocytes was unchanged. Jaundiced patients had significantly higher plasma TGF beta, but TNF alpha and IL-1 beta were below the limits of detection. The highest monocyte TNF alpha and IL-6 levels were seen in malignant disease patients, especially those with a poor immediate prognosis. We conclude that the production of some cytokines by monocytes is up-regulated in patients with obstructive jaundice.


Sujet(s)
Cholestase/sang , Cytokines/sang , Monocytes/métabolisme , Maladies des canaux biliaires/complications , Tumeurs des canaux biliaires/complications , Conduits biliaires intrahépatiques , Études cas-témoins , Cholangiocarcinome/complications , Lithiase biliaire/complications , Cholestase/étiologie , Cholestase/mortalité , Cytokines/biosynthèse , Femelle , Humains , Interleukine-1/sang , Interleukine-6/sang , Mâle , Adulte d'âge moyen , Monocytes/immunologie , Tumeurs du pancréas/complications , Pronostic , Facteur de croissance transformant bêta/sang , Facteur de nécrose tumorale alpha/analyse , Régulation positive
18.
HPB Surg ; 9(4): 219-21, 1996.
Article de Anglais | MEDLINE | ID: mdl-8809582

RÉSUMÉ

Patients with obstructive jaundice have an increased incidence of peri-operative complications and immune dysfunction. This study was to investigate interleukin (IL)-12 (a cellular immunity stimulant), levels in jaundiced patients. 23 jaundiced patients and 17 controls were studied. There was significantly increased monocyte IL-12 production in jaundice, as measured by an ELISA, compared with that in controls (p < 0.01 by Mann-Whitney U test). A similar increase is seen in both benign and malignant jaundice. There was no difference between plasma IL-12 levels in the two groups. It is concluded that in jaundice, monocytes have a significantly increased capacity to release IL-12. This suggests that IL-12 may play a role in the immune dysfunction in jaundiced patients.


Sujet(s)
Cholestase/sang , Interleukine-12/sang , Monocytes/métabolisme , Cholestase/immunologie , Test ELISA , Femelle , Humains , Mâle , Adulte d'âge moyen
19.
Int J Oncol ; 9(2): 279-84, 1996 Aug.
Article de Anglais | MEDLINE | ID: mdl-21541512

RÉSUMÉ

Membrane ruffling of a tumour cell is correlated with its motile and metastatic behaviour. This study examined the effect of gamma linolenic acid (GLA), an anti-cancer agent, on HGF/SF induced membrane ruffling in the human cancer cell line, HT115. HGF induced a rapid appearance of membrane ruffling which was related to increased motility and the tyrosine phosphorylation and translocation of ezrin, a membrane-cytoskeleton linker protein. The presence of GLA significantly inhibited both the membrane ruffling and cell motility of the tumour cells, at sub-toxic concentrations. Western blotting revealed that the tyrosine phosphorylation of ezrin was inhibited by GLA. The translocation ezrin from cytosol and generalised areas of cell membrane to ruffled areas of the membrane induced by HGF/SF was also inhibited as shown by both indirect immunofluorescence and transmission electron microscopy. It is concluded that GLA inhibits HGF/SF induced membrane ruffling via its effect on ezrin, and this provides a further molecular explanation for the anti-tumour action of GLA.

20.
Int J Oncol ; 8(3): 583-7, 1996 Mar.
Article de Anglais | MEDLINE | ID: mdl-21544400

RÉSUMÉ

Gamma linolenic acid (GLA) is an anti-cancer agent recently reported to inhibit tumour cell-matrix attachment. This study examined the effects of GLA on the adhesion of two tumour cell lines, HT115 (human colon) and MDA MB 231 (human breast), to an extracellular matrix, Matrigel. The action of GLA on focal adhesion kinase(FAK) and paxillin was also investigated. Following cell adhesion to Matrigel in control experiments, both FAK and paxillin were quickly tyrosine phosphorylated and become concentrated at focal adhesion areas. Inclusion of GLA resulted in an inhibition of the tyrosine phosphorylation of both FAK and paxillin leading to a reduced attachment of both cell types to Matrigel. FAK and paxillin were also less well distributed in the focal adhesions compared with the controls. It is concluded, therefore, that GLA inhibits tumour-matrix adhesion via the inhibition of FAK and paxillin tyrosine phosphorylation.

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