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1.
Gut Pathog ; 15(1): 65, 2023 Dec 14.
Article in English | MEDLINE | ID: mdl-38098020

ABSTRACT

BACKGROUND: Eimeria genus belongs to the apicomplexan parasite phylum and is responsible for coccidiosis, an intestinal disease with a major economic impact on poultry production. Eimeria tenella is one of the most virulent species in chickens. In a previous study, we showed a negative impact of caecal microbiota on the physiopathology of this infection. However, the mechanism by which microbiota leads to the physiopathology remained undetermined. Macrophages play a key role in inflammatory processes and their interaction with the microbiota during E. tenella infection have never been investigated. We therefore examined the impact of microbiota on macrophages during E. tenella infection. Macrophages were monitored in caecal tissues by immunofluorescence staining with KUL01 antibody in non-infected and infected germ-free and conventional chickens. Caecal cells were isolated, stained, analyzed and sorted to examine their gene expression using high-throughput qPCR. RESULTS: We demonstrated that microbiota was essential for caecal macrophage recruitment in E. tenella infection. Furthermore, microbiota promoted a pro-inflammatory transcriptomic profile of macrophages characterized by increased gene expression of NOS2, ACOD1, PTGS2, TNFα, IL1ß, IL6, IL8L1, IL8L2 and CCL20 in infected chickens. Administration of caecal microbiota from conventional chickens to germ-free infected chickens partially restored macrophage recruitment and response. CONCLUSIONS: Taken together, these results suggest that the microbiota enhances the physiopathology of this infection through macrophage recruitment and activation. Consequently, strategies involving modulation of the gut microbiota may lead to attenuation of the macrophage-mediated inflammatory response, thereby limiting the negative clinical outcome of the disease.

2.
Rev Laryngol Otol Rhinol (Bord) ; 130(4-5): 215-20, 2009.
Article in French | MEDLINE | ID: mdl-20597400

ABSTRACT

OBJECTIVES: Papillary microcarcinoma (PMC) is one of the most frequent pathological forms of thyroid cancer Here, we describe the circumstances of diagnosis and the clinical and pathological characteristics of this tumour We also analyze the therapeutic management and compare it with the recent published guidelines. METHODS: Between 2000 and 2006, a total of 230 patients with a PMC of the thyroid gland were included in this retrospective study. We have investigated the correlations between some pathological parameters (plurifocality, lymph node invasion...) and several factors (age, gender, tumour size...). RESULTS: The diagnosis of PMC was suspected in the preoperative period in 15% of the patients, and was confirmed intraoperatively by the pathologist in 42% of the cases. Plurifocal or bilateral PMC were discovered in respectively 30 and 17% of the patients. The rate of lymph node invasion in the central neck (level VI) was 26%. An elevated tumor size was correlated with a higher rate of plurifocal or bilateral PMC and of lymph node metastasis (p < 0.05). The indications for postoperative radioiodine therapy were reduced by approxiately 50% in the second part of our study. There were no case of thyroid PMC-related death. CONCLUSIONS: Even for these small tumours, tumour size remains correlated with the tumour aggressiveness. The place of radioiodine therapy in the management of thyroid PMC was progressively reduced because of the good prognosis of this tumour.


Subject(s)
Carcinoma, Papillary/pathology , Carcinoma, Papillary/surgery , Thyroid Neoplasms/pathology , Thyroid Neoplasms/surgery , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Lymph Node Excision , Lymphatic Metastasis , Male , Middle Aged , Retrospective Studies , Thyroidectomy , Young Adult
3.
Int J Immunopathol Pharmacol ; 21(3): 515-26, 2008.
Article in English | MEDLINE | ID: mdl-18831919

ABSTRACT

Helicobacter pylori infection is the major cause of gastroduodenal pathologies including gastric cancer. The long persistence of bacteria and the type of immune and inflammatory response determine the clinical issue. In this study, the global gene expression profile after 6 and 12 months of H. pylori infection was investigated in the mouse stomach, using the Affymetrix GeneChip Mouse Expression Array A430. Genes related to the inflammatory and immune responses were focused. Levels of selected transcripts were confirmed by reverse transcription polymerase chain reaction. Twenty- five and nineteen percent of the differentially expressed genes observed at 6 and 12 months post-infection respectively, were related to immune response. They are characterized by an interferon (IFN)gamma-dependent expression associated to a T helper 1 (Th1) polarised response. In-depth analysis revealed that an up-regulation of IL-23p19, took place in the stomach of H. pylori infected-mice. Strong IL-23p19 levels were also confirmed in gastric biopsies from H. pylori-infected patients with chronic gastritis, as compared to healthy subjects. Our microarray analysis revealed also, a high decrease of H+K+-ATPase transcripts in the presence of the H. pylori infection. Association of gastric Th1 immune response with hypochlorhydria through the down-regulation of H+K+-ATPase contributes to the genesis of lesions upon the H. pylori infection. Our data highlight that the up-regulation of IL-23 and of many IFNgamma signature transcripts occur early on during the host response to H. pylori, and suggest that this type of immune response may promote the severity of the induced gastric lesions.


Subject(s)
Gene Expression Profiling , Helicobacter Infections/immunology , Helicobacter pylori , Interferon-gamma/physiology , Interleukin-23/genetics , Animals , Gastric Mucosa/metabolism , Gene Expression Regulation , H(+)-K(+)-Exchanging ATPase/physiology , Helicobacter Infections/metabolism , Male , Mice , Mice, Inbred C57BL , Oligonucleotide Array Sequence Analysis , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction , Up-Regulation
4.
J Clin Endocrinol Metab ; 92(7): 2487-95, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17426102

ABSTRACT

BACKGROUND: Serum thyroglobulin (Tg) is the marker of differentiated thyroid cancer after initial treatment and TSH stimulation increases its sensitivity for the diagnosis of recurrent disease. AIM: The goal of the study is to compare the diagnostic values of seven methods for serum Tg measurement for detecting recurrent disease both during L-T4 treatment and after TSH stimulation. METHODS: Thyroid cancer patients who had no evidence of persistent disease after initial treatment (total thyroidectomy and radioiodine ablation) were studied at 3 months on L-T4 treatment (Tg1) and then at 9-12 months after withdrawal or recombinant human TSH stimulation (Tg2). Sera with anti-Tg antibodies or with an abnormal recovery test result were excluded from Tg analysis with the corresponding assay. The results of serum Tg determination were compared to the clinical status of the patient at the end of follow-up. RESULTS: Thirty recurrences were detected among 944 patients. A control 131I total body scan had a low sensitivity, a low specificity, and a low clinical impact. Assuming a common cutoff for all Tg assays at 0.9 ng/ml, sensitivity ranged from 19-40% and 68-76% and specificity ranged from 92-97% and 81-91% for Tg 1 and Tg2, respectively. Using assays with a functional sensitivity at 0.2-0.3 ng/ml, sensitivity was 54-63% and specificity was 89% for Tg1. Using the two methods with a lowest functional sensitivity at 0.02 and 0.11 ng/ml resulted in a higher sensitivity for Tg1 (81% and 78%), but at the expense of a loss of specificity (42% and 63%); finally, for these two methods, using an optimized functional sensitivity according to receiver operating characteristic curves at 0.22 and 0.27 ng/ml resulted in a sensitivity at 65% and specificity at 85-87% for Tg1. CONCLUSION: Using an assay with a lower functional sensitivity may give an earlier indication of the presence of Tg in the serum on L-T4 treatment and may be used to study the trend in serum Tg without performing any TSH stimulation. Serum Tg determination obtained after TSH stimulation still permits a more reliable assessment of cure and patient's reassurance.


Subject(s)
Carcinoma, Papillary, Follicular/blood , Carcinoma, Papillary, Follicular/diagnostic imaging , Chemistry, Clinical/methods , Thyroglobulin/analysis , Thyroglobulin/blood , Thyroid Neoplasms/blood , Thyroid Neoplasms/diagnostic imaging , Adult , Biomarkers/blood , Carcinoma, Papillary, Follicular/therapy , Female , Follow-Up Studies , Humans , Iodine Radioisotopes , Male , Middle Aged , Neoplasm Recurrence, Local/blood , Neoplasm Recurrence, Local/diagnostic imaging , Prospective Studies , Radionuclide Imaging , Remission Induction , Sensitivity and Specificity , Thyroid Neoplasms/therapy
5.
Life Sci ; 73(4): 499-507, 2003 Jun 13.
Article in English | MEDLINE | ID: mdl-12759143

ABSTRACT

The importance of the inflammatory process in the pathology of experimental Mg-deficiency has been reconsidered but the sequence of events leading to inflammatory response remains unclear. In this study, the effect of Mg-deficiency on complement system by measuring total C3 concentration, mRNA abundance for rat pre-pro complement C3 in liver by RT-PCR, complement haemolytic activity and C3 activation by Western Blot was studied. Weaning male Wistar rats were fed either Mg-deficient or control experimental diets for 2 or 8 days. At 8 days, a characteristic inflammatory response of Mg-deficiency including hyperaemia, leukocytosis and enlarged spleen was accompanied by an increase in the total C3 quantity in plasma. Moreover, at 8 days, RT-PCR analysis indicated higher level of mRNA rat pre-pro complement C3 in liver from Mg-deficient rats compared to control rats. Even if the inflammatory syndrome was not observed in rats after 2 days, total plasma C3 was shown to be significantly increased as compared to total plasma C3 level in control rats. Because of the high variability of complement haemolytic activity values in Wistar rats, weaning male Sprague-Dawley rats were used in a second experiment. At 8 days, the inflammatory response of Sprague-Dawley rats was accompanied by an increase in total C3 quantity and by a higher haemolytic activity. The Western Blot technique failed to display distinct bands resulting from C3 cleavage in plasma from Mg-deficient rats. Since, the complement C3 is a positive acute phase reactant, the elevation of C3 indicates that the modification of inflammatory response is an early event of Mg-deficiency. However, complement activation does not appear to be involved in the acute phase of the deficiency.


Subject(s)
Complement C3/metabolism , Liver/metabolism , Magnesium Deficiency/metabolism , Magnesium/blood , Animals , Blotting, Western , Complement C3/chemistry , Enzyme-Linked Immunosorbent Assay , Inflammation/drug therapy , Male , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Rats, Wistar , Reverse Transcriptase Polymerase Chain Reaction , Time Factors
6.
Magnes Res ; 15(1-2): 37-42, 2002 Mar.
Article in English | MEDLINE | ID: mdl-12030422

ABSTRACT

Recent studies underline the importance of the immunoinflammatory processes in the pathology of acute magnesium (Mg)-deficiency. The aim of this study was to assess the effect of acute experimental Mg-deficiency in the rat on neutrophil activity. Weaning male Wistar rats were fed either a Mg-deficient or a control diet for 8 days. In this experiment, we measured neutrophil respiratory burst by chemiluminescence; then, to examine the molecular events associated with acute Mg-deficiency, we applied cDNA array technology to define the transcription response in neutrophils of Mg-deficient rats in comparison with controls. In Mg-deficient rats, the characteristic inflammatory response was accompanied by a marked increase in the number of neutrophils. Moreover, as shown by chemiluminescence studies, basal neutrophil activity from Mg-deficient rats was significantly elevated when compared to neutrophils from control rats. Moreover, the chemiluminescence of neutrophils from Mg-deficient rats was significantly higher than that of control rats following phorbol myristate acetate or opsonized zymosan activation. Using cDNA array which includes 207 known rat genes of stress proteins, 102 genes were found to be expressed in neutrophils. Among expressed genes, 78 per cent of genes were found to be expressed more than twofold in neutrophils from Mg-deficient rats compared to control rats. Acute Mg-deficiency was characterized by an induction of genes encoding for proteins involved in apoptosis, heat shock proteins, protein belonging to the cytoskeleton, proteins implicated as stress response regulators and effectors and enzyme implicated in thromboxane synthesis. Then, this experimental strategy allowed to identify a series of genes implicated in the immunoinflammatory process of Mg-deficiency.


Subject(s)
Magnesium Deficiency/genetics , Magnesium Deficiency/metabolism , Neutrophil Activation , Neutrophils/metabolism , Animals , Apoptosis , DNA, Complementary/metabolism , Gene Expression , Inflammation , Male , Oligonucleotide Array Sequence Analysis , RNA, Messenger/metabolism , Rats , Rats, Wistar , Time Factors
7.
Magnes Res ; 15(1-2): 43-8, 2002 Mar.
Article in English | MEDLINE | ID: mdl-12030423

ABSTRACT

In view of experimental data suggesting that pharmacological magnesium (Mg) therapy could be expected to temper hypersensitivity, the aim of the present study was to assess the effect of in vitro high Mg concentration (8 mmol/l vs. 0.8 mmol/l) on human leukocyte activation. The first experiment in nine healthy volunteers was performed on total leukocyte suspension containing 82 +/- 4 per cent of neutrophils. The results demonstrate the inhibitory effect of high Mg concentration as shown by the significant reduction of superoxide anion production following phorbol myristate acetate (PMA) or formyl-methionyl-leucyl-phenylalanine (fMLP) activation. Moreover, neutrophils activated with fMLP showed an increased respiratory burst when incubated in low Mg concentration (0.2 mmol/l) as compared to normal Mg concentration (0.8 mmol/l). Similarly, high concentration of Mg resulted in a significant reduction in superoxide anion production by eosinophils in response to PMA in five eosinophilic patients. In patients showing Hymenoptera venom hypersensitivity, high Mg concentration resulted in a significant reduction of sulphidoleukotrienes production by leukocytes in response to venom allergen (six patients) or in response to zymosan activated particules (fourteen patients). Taken together, the results suggests that Mg acts via a non specific mechanism and appears to be non specific to a particular cell type. As Mg counteracts calcium in many physiological and pathological processes, it is reasonable to hypothesise that extracellular Mg can diminish leukocyte activation by its calcium antagonism.


Subject(s)
Leukocytes/metabolism , Magnesium/pharmacology , Neutrophil Activation , Anions , Calcium/antagonists & inhibitors , Eosinophils/metabolism , Humans , In Vitro Techniques , Leukotrienes/metabolism , Magnesium/metabolism , N-Formylmethionine Leucyl-Phenylalanine/pharmacology , Oxygen/metabolism , Reactive Oxygen Species , Superoxides , Tetradecanoylphorbol Acetate/pharmacology
8.
Dev Cell ; 1(5): 633-44, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11709184

ABSTRACT

Increased protection from reactive oxygen species (ROS) is believed to increase life span. However, it has not been clearly demonstrated that endogenous ROS production actually limits normal life span. We have identified a mutation in the Caenorhabditis elegans iron sulfur protein (isp-1) of mitochondrial complex III, which results in low oxygen consumption, decreased sensitivity to ROS, and increased life span. Furthermore, combining isp-1(qm150) with a mutation (daf-2) that increases resistance to ROS does not result in any significant further increase in adult life span. These findings indicate that both isp-1 and daf-2 mutations increase life span by lowering oxidative stress and result in the maximum life span increase that can be produced in this way.


Subject(s)
Caenorhabditis elegans/metabolism , Electron Transport Complex III/metabolism , Iron-Sulfur Proteins/metabolism , Longevity , Mitochondria/metabolism , Oxidative Stress , Amino Acid Sequence , Animals , Caenorhabditis elegans/embryology , Caenorhabditis elegans/genetics , Caenorhabditis elegans/growth & development , Caenorhabditis elegans Proteins/chemistry , Caenorhabditis elegans Proteins/genetics , Caenorhabditis elegans Proteins/metabolism , Cloning, Molecular , Cytochrome b Group/genetics , Cytochrome b Group/metabolism , Electron Transport/drug effects , Electron Transport/genetics , Electron Transport Complex III/chemistry , Electron Transport Complex III/genetics , Forkhead Transcription Factors , Helminth Proteins/genetics , Humans , Iron-Sulfur Proteins/chemistry , Iron-Sulfur Proteins/genetics , Longevity/genetics , Mitochondria/chemistry , Mitochondria/drug effects , Models, Molecular , Mutation , Oxidative Stress/drug effects , Oxidative Stress/genetics , Oxygen/metabolism , Oxygen Consumption/drug effects , Oxygen Consumption/genetics , Paraquat/pharmacology , Phenotype , Protein Conformation , Reactive Oxygen Species/metabolism , Receptor, Insulin/genetics , Receptor, Insulin/metabolism , Sequence Homology, Amino Acid , Transcription Factors/genetics , Transcription Factors/metabolism
9.
Trends Genet ; 17(12): 712-8, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11718925

ABSTRACT

The nematode Caenorhabditis elegans is used as a model system for the study of aging. Several mutant strains that have an increased lifespan have been isolated and characterized genetically and molecularly. Molecular analysis reveals that diverse types of gene products can affect worm lifespan, including proteins active in signal transduction, transcription and silencing factors, mitochondrial enzymes, and at least one protein that affects telomere length. Genetic analysis, however, suggests that these activities all converge on a few key mechanisms that impinge on lifespan, namely the production, repair and prevention of molecular damage.


Subject(s)
Caenorhabditis elegans/genetics , Caenorhabditis elegans/physiology , Longevity/genetics , Animals , Caenorhabditis elegans/growth & development , Caenorhabditis elegans Proteins/genetics , Caenorhabditis elegans Proteins/physiology , DNA Damage , DNA Repair , Gene Silencing , Genetic Variation , Models, Biological , Mutation , Signal Transduction , Transcription, Genetic
10.
Genetics ; 159(1): 147-57, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11560893

ABSTRACT

We show that the phenotype associated with gro-1(e2400) comprises the whole suite of features that characterize the phenotype of the clk mutants in Caenorhabditis elegans, including deregulated developmental, behavioral, and reproductive rates, as well as increased life span and a maternal effect. We cloned gro-1 and found that it encodes a highly conserved cellular enzyme, isopentenylpyrophosphate:tRNA transferase (IPT), which modifies a subset of tRNAs. In yeast, two forms of the enzyme are produced by alternative translation initiation, one of which is mitochondrial. In the gro-1 transcript there are also two possible initiator ATGs, between which there is a sequence predicted to encode a mitochondrial localization signal. A functional GRO-1::GFP fusion protein is localized diffusely throughout the cytoplasm and nucleus. A GRO-1::GFP initiated from the first methionine is localized exclusively to the mitochondria and rescues the mutant phenotype. In contrast, a protein initiated from the second methionine is localized diffusely throughout the cell and does not rescue the mutant phenotype. As oxygen consumption and ATP concentration have been reported to be unaffected in gro-1 mutants, our observations suggest that GRO-1 acts in mitochondria and regulates global physiology by unknown mechanisms.


Subject(s)
Alkyl and Aryl Transferases/chemistry , Alkyl and Aryl Transferases/genetics , Caenorhabditis elegans/genetics , Caenorhabditis elegans/metabolism , Mitochondria/enzymology , RNA, Transfer/metabolism , Adenosine Triphosphate/metabolism , Amino Acid Sequence , Animals , Chromosome Mapping , Cloning, Molecular , Female , Green Fluorescent Proteins , Luminescent Proteins/metabolism , Male , Models, Genetic , Molecular Sequence Data , Mutation , Operon , Oxygen Consumption , Phenotype , Polymerase Chain Reaction , Protein Binding , Protein Biosynthesis , RNA/metabolism , RNA Splicing , RNA, Messenger/metabolism , Recombinant Fusion Proteins/metabolism , Sequence Homology, Amino Acid , Time Factors
11.
Neuroimage ; 13(5): 896-902, 2001 May.
Article in English | MEDLINE | ID: mdl-11304085

ABSTRACT

Apathy is the most frequent behavioral symptom in Alzheimer's disease and is also frequently reported in other brain organic disorders occurring in the elderly. Based on the literature, we hypothesized that apathy was related to an anterior cingulate hypofunction. Forty-one subjects were studied. According to ICD 10 diagnostic criteria, 28 patients had Alzheimer dementia (demented: diagnostic group 1), and 13 had organic personality disorders or mild cognitive impairment not attributable to dementia (nondemented: diagnostic group 2). Apathy was evaluated by the Neuro-Psychiatric Inventory. As a result each diagnostic group was divided into two symptomatic subgroups: apathetic or nonapathetic. Brain perfusion was measured by (99m)Tc-labeled bicisate (ECD) brain SPECT and the images were compared using Statistical Parametric Mapping (SPM96). We began by comparing apathetic vs nonapathetic patients, whatever their diagnostic group (whole population), then analyzed them within each group. Twenty-one subjects were apathetic (14 in group 1 and 7 in group 2) and 20 were not (14 in group 1 and 6 in group 2). For the whole population, the Z map showed a significant decrease in ECD uptake for the apathetic patients in the anterior cingulate (P < 0.002) bilaterally. This area was also identified as hypoactive by SPM analysis in the demented (P < 0.035) and in the nondemented (P < 0.02) apathetic patient groups. Finally, conjunction analysis indicated that the anterior cingulate was the common hypoactive structure of the two apathetic subgroups (Z = 4.35, P < 0.0009). These results point to a close relationship between apathy and the anterior cingulate region.


Subject(s)
Alzheimer Disease/diagnostic imaging , Brain Mapping , Brain/diagnostic imaging , Gyrus Cinguli/diagnostic imaging , Motivation , Tomography, Emission-Computed, Single-Photon , Aged , Aged, 80 and over , Alzheimer Disease/physiopathology , Brain/blood supply , Female , Gyrus Cinguli/blood supply , Humans , Image Processing, Computer-Assisted , Male , Mathematical Computing , Neuropsychological Tests , Reference Values , Regional Blood Flow/physiology
12.
Cerebrovasc Dis ; 10(5): 364-73, 2000.
Article in English | MEDLINE | ID: mdl-10971022

ABSTRACT

OBJECTIVES: Accurate prediction of outcome in acute stroke would help in identifying subgroups of patients for therapeutic trials and intravenous thrombolysis. The purpose of this study was to prospectively test the hypothesis that brain SPECT, with (99m)Tc-L, L-ethylcysteinate dimer (ECD), a tracer sensitive to cell function, performed in the first hours after stroke onset, adds predictive power to concomitant neurological evaluation. METHODS: Twenty-four patients with a first-ever middle cerebral artery stroke were prospectively studied with ECD-SPECT within 12 h after stroke onset. Neurological evaluation was performed using Orgogozo's scale at admission and 3 months later in order to calculate the percent Martinez-Vila evolution indices (EI%). Semiquantitative visual analysis of SPECT images was performed in 6 cortical regions relevant for carotid artery territory. Both the extent and the intensity of cortical reduced ECD uptake were calculated, leading to an 'ischemia' score, corresponding to the sum of regions of interest (ROI) where ECD uptake was between 40 and 80% of the contralateral healthy hemisphere, and an 'irreversibly damaged tissue' (IDT) score, corresponding to an uptake below 40%, and a total score (ischemia + IDT). Each patient was assigned to one of three patterns: (1) pattern I with severe ECD cortical uptake reduction defined by at least one ROI with uptake under 40%, (2) pattern II with moderate ECD cortical uptake reduction (40-80%) only and (3) pattern III with normal ECD uptake. RESULTS: There were 11 patients (46%) with pattern I ECD-SPECT. This group had almost invariably (10/11 patients) a poor outcome. The 12 patients (50%) classified in pattern II had a variable clinical outcome, ranging from improvement to deterioration. The single patient with a normal SPECT (pattern III) had a full clinical recovery. Both total score and IDT score were strongly significantly correlated with neurological recovery EI% (respectively p = 0.006 and 0.004). Their predictive value was significantly higher than, and independent of, day 0 neurological evaluation. No patient had an increased ECD uptake. CONCLUSION: Our results show that the degree of ECD cortical uptake reduction, measured on early brain SPECT, is a strong predictor of neurological recovery. ECD-SPECT data have a higher predictive value than day 0 neurological evaluation. The apparently better predictive value of ECD over hexamethylpropyleneamine oxime may reflect this tracer's brain retention mechanisms which are weighted more towards cell function than towards perfusion. ECD-SPECT is easily obtainable and may help in selecting out from therapy those patients who are likely to have either very good or very poor spontaneous outcome, and thus improve the assessment of acute stroke and the choice of therapeutic strategy.


Subject(s)
Cysteine/analogs & derivatives , Organotechnetium Compounds , Radiopharmaceuticals , Stroke Rehabilitation , Stroke/diagnostic imaging , Tomography, Emission-Computed, Single-Photon/methods , Acute Disease , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Neurologic Examination , Predictive Value of Tests , Prognosis , Prospective Studies , Recovery of Function , Tomography, X-Ray Computed
13.
J Virol ; 74(6): 2647-54, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10684279

ABSTRACT

We have investigated the secondary structure of peach latent mosaic viroid (PLMVd) in solution, and we present here the first description of the structure of a branched viroid in solution. Different PLMVd transcripts of plus polarity were produced by using the circularly permuted RNA method and the exploitation of RNA internal secondary structure to position the 5' and 3' termini and studied by nuclease mapping and binding shift assays using DNA and RNA oligonucleotides. We show that PLMVd folds into a complex, branched secondary structure. In general, this structure is similar to that reported previously, which was based on sequence comparison and computer modelling. The structural microheterogeneity is apparently limited to only some small domains. More importantly, this structure includes a novel pseudoknot that is conserved in all PLMVd isolates and seems to allow folding into a very compact form. This pseudoknot is also found in chrysanthemum chlorotic mottle viroid, suggesting that it is a unique feature of the viroid members of the PLMVd subgroup.


Subject(s)
Mosaic Viruses/genetics , RNA, Viral/chemistry , Viroids/genetics , Base Sequence , Chromosome Mapping , Fruit/virology , Molecular Sequence Data , Nucleic Acid Conformation , RNA, Viral/biosynthesis , Ribonucleases , Solutions
14.
Clin Sci (Lond) ; 97(6): 657-69, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10585893

ABSTRACT

Dietary supplementation with glutamine (Gln), arginine (Arg) or ornithine 2-oxoglutarate (alpha-ketoglutarate; OKG) has attracted recent attention for the potential to improve anti-cancer immune function. However, since these compounds have not been compared systematically in an internally controlled study, their relative efficacy is difficult to estimate. Buffalo rats were fed on nutritionally complete semi-purified diets supplemented with Gln, Arg or OKG for 14 days after implantation of the Morris hepatoma 7777 (n>/=7 per diet). The control diet was made isonitrogenous and isoenergetic by addition of a mixture of non-essential amino acids. After 14 days, peritoneal macrophages and splenocytes were isolated to determine cell phenotypes, macrophage cytostatic activity and natural killer (NK) cell cytotoxicity, as well as nitric oxide (NO) and cytokine production. Diet had no effect on tumour weight (1.6+/-0.2 g; n=59). However, rats fed OKG had increased macrophage cytostatic activity and NK cell cytotoxicity (P<0.05). Although enhanced killing ability by NK cells was associated with higher splenocyte NO production (P<0.04), increased cytotoxicity was not inhibited by a specific inhibitor of inducible NO synthase. The proportion of interleukin-2-receptor-positive T cells after stimulation increased in rats fed OKG (P<0.05); however, cytokine production was not affected by diet. None of OKG, Gln or Arg altered tumour growth compared with a control mixture of non-essential amino acids. These results suggest no net advantage for anti-cancer immunity, but do not preclude benefits in immune responses to disease recurrence or metastasis, therapy or secondary infection.


Subject(s)
Arginine/administration & dosage , Glutamine/administration & dosage , Liver Neoplasms, Experimental/immunology , Ornithine/analogs & derivatives , Analysis of Variance , Animals , Arginine/metabolism , Cytokines/metabolism , Cytotoxicity Tests, Immunologic , Enzyme Inhibitors/pharmacology , Female , Fluorescent Antibody Technique, Indirect , Glutamine/metabolism , Interferon-gamma/metabolism , Isothiuronium/analogs & derivatives , Isothiuronium/pharmacology , Killer Cells, Natural/immunology , Liver Neoplasms, Experimental/metabolism , Lymphocyte Activation , Macrophages, Peritoneal/immunology , NG-Nitroarginine Methyl Ester/pharmacology , Nitric Oxide/metabolism , Nitric Oxide Synthase/antagonists & inhibitors , Nitrites/analysis , Ornithine/administration & dosage , Ornithine/metabolism , Rats , Rats, Inbred BUF , Receptors, Interleukin-2/metabolism , T-Lymphocytes/immunology , Tumor Necrosis Factor-alpha/metabolism
15.
J Nucl Med ; 40(8): 1301-9, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10450681

ABSTRACT

UNLABELLED: It has been shown in clinical studies that for subjects with a low likelihood of coronary artery disease (CAD), attenuation correction (AC) improves the specificity of defect detection in the inferior wall (right coronary artery [RCA] region). The aim of this study was to investigate the effect of AC on the visual interpretation of the RCA and anteroseptal (corresponding to the left anterior descending artery [LAD]) regions in CAD patients. METHODS: Fifty-six patients with suspected CAD underwent 20Tl stress/4 h-delayed imaging SPECT using a simultaneous 201Tl emission/99mTc transmission imaging protocol. Images were reconstructed using the maximum likelihood-expectation maximum algorithm without and with AC. The stress/4 h-delayed images were interpreted blindly for reversible or fixed defects in the RCA and LAD regions by three experienced physicians. Coronary angiography, electrocardiography and enzyme findings were used to establish diagnoses of ischemia or infarction, and receiver operating characteristic (ROC) analyses were performed. RESULTS: Statistical testing of ROC curve areas showed that defect detection performance improved with AC when compared with performance without AC in the RCA region. This was mainly the result of a systematic increase in specificity of 12% or more (for any observer and any type of defect) for a similar sensitivity (no definite change in sensitivity values). However, defect detection performance significantly decreased in the LAD territory with AC images (P < 0.05) because of a systematic decrease in sensitivity of 20% or more, with no consistent change in specificity. Similar trends were observed when reversible and fixed defects were considered separately. CONCLUSION: AC significantly affects the visual interpretation of 201Tl stress/4 h-delayed SPECT images. This study confirmed the increase in specificity obtained with AC in the RCA territory. However, in the population considered, the studied AC was deleterious for the LAD territory assessment.


Subject(s)
Coronary Disease/diagnostic imaging , Heart/diagnostic imaging , Myocardium/metabolism , Thallium Radioisotopes , Tomography, Emission-Computed/methods , Tomography, X-Ray/methods , Exercise Test , Humans , Male , Middle Aged , Sensitivity and Specificity
16.
J Virol ; 73(8): 6353-60, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10400727

ABSTRACT

We characterized the peach latent mosaic viroid (PLMVd) replication intermediates that accumulate in infected peach leaves and determined the tissue and subcellular localization of the RNA species. Using in situ hybridization, we showed that PLMVd strands of both plus and minus polarities concentrate in the cells forming the palisade parenchyma. At the cellular level, PLMVd was found to accumulate predominantly in chloroplasts. Northern blot analyses demonstrated that PLMVd replicates via a symmetric mode involving the accumulation of both circular and linear monomeric strands of both polarities. No multimeric conformer was detected, indicating that both strands self-cleave efficiently via their hammerhead sequences. Dot blot hybridizations revealed that PLMVd strands of both polarities accumulate equally but that the relative concentrations vary by more than 50-fold between peach cultivars. Taken together these results establish two hallmarks for the classification of viroids. Group A viroids (e.g., PLMVd), which possess hammerhead structures, replicate in the chloroplasts via the symmetric mode. By contrast, group B viroids, which share a conserved central region, replicate in the nucleus via an asymmetric mechanism. This is an important difference between self-cleaving and non-self-cleaving viroids, and the implications for the evolutionary origin and replication are discussed.


Subject(s)
Fruit/virology , Viroids/genetics , Virus Replication , In Situ Hybridization , RNA, Viral , Subcellular Fractions , Viroids/physiology
17.
Nucleic Acids Res ; 27(1): 186-7, 1999 Jan 01.
Article in English | MEDLINE | ID: mdl-9847175

ABSTRACT

This is an online database to facilitate research on viroid, viroid-like RNAs and human hepatitis delta virus (vHDV) by presenting a large number of sequences and related data in a comprehensive and user-friendly format (e.g. position of their self-catalytic domains, open reading frame of the vHDV, prediction of the most stable secondary structures, etc.). Most of these RNA species share a common proposed replication pattern known as a DNA-independent rolling circle mechanism. Together, these species form the 'brotherhood' of the smallest known auto-replicable RNAs. This online database is available on the World Wide Web at http://www.callisto.si.usherb.ca/jpperra


Subject(s)
Databases, Factual , Hepatitis Delta Virus/genetics , RNA, Viral/genetics , Viroids/genetics , Humans , Internet , Phylogeny , RNA/genetics , RNA, Catalytic/genetics , RNA, Circular , RNA, Satellite/genetics , Sequence Alignment , Terminology as Topic
18.
Rev Chir Orthop Reparatrice Appar Mot ; 85(8): 803-10, 1999 Dec.
Article in French | MEDLINE | ID: mdl-10637881

ABSTRACT

PURPOSE OF THE STUDY: The goal of this study was to determine the place and the limit of the arthroscopic management of septic knee arthritis. This procedure is an alternative treatment to needle aspiration and to open arthrotomy drainage. MATERIAL AND METHODS: Sixteen adult patients were treated between 1993 and 1997 for pyogenic septic arthritis of the knee. The duration of symptoms prior to arthroscopic debridement was 4.5 days (range, one to 14 days). In 8 patients the infection was hematogenous. 5 patients had post-operative infection, 2 had post-traumatic infection and one infection followed an intraarticular injection. All the patients were treated by arthroscopic debridement and irrigation of the knee. A partial synovectomy of the anterior compartment was carried out in 4 cases in which the infection diagnosis was delayed. In 6 patients with resistant germ or early unfavorable course (clinically or biologically), an early iterative arthroscopy was performed between 2 and 7 days after the first procedure. The medical treatment consisted in a double systemic antibiotherapy for an average duration of 4 weeks, followed by oral treatment for 3 weeks. The patients were encouraged to mobilize their knee as soon as C Reactiv Protein was normal (average 3 weeks, 0 to 12). RESULTS: The average follow up was 20.5 months (2 to 60). Two elderly patients died, one directly related to knee infection. One patient with prior patella osteosynthesis had a recurrent infection 10 months after the arthroscopy. Thirteen out of 14 patients had an excellent or good functional result. DISCUSSION: Arthroscopic drainage is a valuable alternative procedure for the treatment of the septic arthritis. Arthroscopic treatment leads to a more effective infectious result than needle aspiration procedure and the functional result is better than with open drainage. Septic arthritis in the elderly or in patients with multiple organ failure have a poor prognosis. The treatment of pyoarthrosis of the knee must be aggressive and we frequently propose an iterative arthroscopic drainage, specially in case of delayed treatment, early unfavorable course or multiresistant germ.


Subject(s)
Arthritis, Infectious/surgery , Arthroscopy , Knee Joint , Adolescent , Adult , Aged , Aged, 80 and over , Arthritis, Infectious/diagnosis , Arthroscopy/methods , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prognosis , Punctures , Retrospective Studies
19.
Mutat Res ; 403(1-2): 45-53, 1998 Jul 17.
Article in English | MEDLINE | ID: mdl-9726005

ABSTRACT

We studied the polymorphisms m1 (Msp1 restriction site) and m2 (codon Val substitution) of CYP1A1 gene and the copy number of glutathione S-transferase mu1 (GSTM1) gene on 487 DNA of breast cancer primary tumours from Caucasian group. Tumours of patients aged 55 years and under at diagnosis presented a great proportion of wild m1 (-/-) genotype; 83.6% vs. 69.5% (p < 0.0006), and a higher percentage of copy number of GSTM1 equal or under one copy; 65.2% vs. 53.4% (p < 0.011) for older patients m1 and m2 variants are closely linked (p < 0.0000). Tumour with a low copy number of GSTM1 is correlated with high histological grading (p < 0.01) and high Cathepsin D concentrations (p < 0.02). The combinations of different genotypes showed that association wild m1 (-/-) genotype and copy number of GSTM1 inferior or equal to one copy is correlated with an early onset of breast cancer primary tumour 44% vs. 6.4% for m1 (-/+) or (+/+) genotype and copy number of GSTM1 superior to one (p < 0.0000). The CYP1A1 gene wild form seems to be associated with early cancer development in Caucasian patients.


Subject(s)
Breast Neoplasms/enzymology , Breast Neoplasms/genetics , Cytochrome P-450 CYP1A1/genetics , Glutathione Transferase/genetics , Polymorphism, Genetic , Adult , Aged , Aged, 80 and over , Breast Neoplasms/metabolism , Cathepsin D/metabolism , DNA, Neoplasm/genetics , Deoxyribonuclease HpaII , Female , Gene Amplification , Genotype , Humans , Middle Aged , Point Mutation , Polymorphism, Restriction Fragment Length , Prognosis , Proteins/metabolism , Receptors, Estrogen/metabolism , Receptors, Progesterone/metabolism , Trefoil Factor-1 , Tumor Suppressor Proteins
20.
Bull Cancer ; 84(1): 35-40, 1997 Jan.
Article in French | MEDLINE | ID: mdl-9180857

ABSTRACT

Glutathione S-transferases mu (GSTM) are dimeric cytosolic isoenzymes. They catalyze glutathione conjugation upon a large variety of electrophiles as carcinogens, trans-stilbene peroxide or benzo(a)pyrene. The gene GSTM1 is localized on chromosome 1p13, it has drawn attention because it is absent approximately in 50% of the white population. GSTM1 null genotype seems linked with susceptibility to cancers as lung, colon and bladder cancers. We have studied GSTM1 genotype from 373 primary breast tumours. The GSTM1 null genotype was found in 50% of the cases (185/373). The incidence study of GSTM1 copy number on clinical and biological variables displayed a significant difference (p < 0.01) of the GSTM1 genotype, showed by the tumour, according to the patient age at diagnosis. The patients younger than 55 years had a percentage more important of primary tumours (65%) with a copy number of GSTM1 gene, inferior or equal at one, compared to the patients older than 55 years (52%). The tumours, whose cathepsin D level was high, presented few copies of GSTM1 gene (p < 0.03). There was no other relationship, particularly, with tumour size, node status, histological type, hormonal receptors, pS2 cytosolic level GSTM1 gene seems protect the mammary gland from cancerogenesis with its detoxification role. This results had not, pointed out in breast cancer, yet.


Subject(s)
Breast Neoplasms/genetics , Glutathione Transferase/analysis , Polymorphism, Genetic , Adult , Age Factors , Aged , Aged, 80 and over , Breast Neoplasms/enzymology , DNA/genetics , Female , Gene Frequency , Genetic Predisposition to Disease , Genotype , Glutathione Transferase/genetics , Humans , Middle Aged , Polymerase Chain Reaction
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