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C Arnal

Publications and source records attributed to C Arnal.

At least 19 recordsLinked to original sources
PubMed2006

Phylogenetic relationships and evolution of cleaning behaviour in the family Labridae: importance of body colour pattern.

The family Labridae contains numerous fishes known to act as cleaners in the wild. Previous studies suggested that a small body size and specific colour patterns may be prerequisites for cleaning. We investigated whether cleaning behaviour is linked to particular fish phenotypes. We first present a phylogeny based on partial 12S rRNA gene sequences of 32 wrasses sampled from different localities in the Indo-Pacific and Atlantic oceans, and in the Mediterranean Sea. Secondly, descriptive data (fish body size, fish body shape and fish body colour patterns) were analyzed in a phylogenetic context using comparative methods. We found no relationship between fish cleaning behaviour and fish body size and shape, but instead a correlation between cleaning behaviour and the presence of a dark lateral stripe within wrasses. Our results suggest that the evolution of cleaning depends upon the presence of a dark median lateral stripe on the fish body surface.

Animals↗
PubMed2005

Assessing the cost of groundwater pollution: the case of diffuse agricultural pollution in the Upper Rhine valley aquifer.

This paper presents an assessment of the costs of diffuse groundwater pollution by nitrates and pesticides for the industrial and the drinking water sectors in the Upper Rhine valley, France. Pollution costs which occurred between 1988 and 2002 are described and assessed using the avoidance cost method. Geo-statistical methods (kriging) are then used to construct three scenarios of nitrate concentration evolution. The economic consequences of each scenario are then assessed. The estimates obtained are compared with the results of a contingent valuation study carried out in the same study area ten years earlier.

Agriculture↗
PubMed2000

Nocardia infection of a joint prosthesis complicating systemic lupus erythematosus.

The authors report the case of a 43-year-old woman suffering from severe systemic lupus erythematosus treated with long-term prednisone, who developed Nocardia nova infection on a hip prosthesis. Sepsis occurred about two years after an episode of pulmonary nocardiosis with the same Nocardia species, that was successfully treated by 12 months of antibiotics. A good outcome of the joint infection was observed in response to antibiotics and removal of the prosthesis. Nocardiosis is a rare infection, acting as an opportunistic infection, facilitated in the present case by systemic lupus erythematosus and chronic corticosteroid therapy. Nocardia infections mainly affect the lungs, skin and central nervous system; these last two sites are mostly due to haematogenous spread, a frequent event. Treatment is based on antibiotics, usually continued for 3-12 months, especially because of the risk of relapse. The imipenem-amikacin combination appears to be more effective than trimethoprim sulfamethoxazole. To our knowledge, this is the first case report of Nocardia nova joint prosthesis infection also presenting as late septic spread of pulmonary nocardiosis, complicating corticosteroid-treated systemic lupus erythematosus.

Adrenal Cortex Hormones↗
PubMed2000

[Infective endocarditis following incomplete ablation of a pacemaker].

Pacemaker lead-related infective endocarditis is uncommon but mortality remains high. We report the case of a 63-year-old man who presented with a history of intermittent low-grade fever and no other sign for 15 months. Fever had developed after incomplete removal of a pacemaker with the ventricular lead left in situ followed by a new implantation of cardiac stimulation material. Positive blood cultures and transesophageal echocardiography showing a vegetation on a pacemaker lead gave the diagnosis. Initial antibiotic therapy was insufficient and complete surgical extraction of the pacemaker and leads was required. A huge vegetation was seen on the old ventricular lead. The other leads were not affected. Outcome was good. The paucity of symptoms in pacemaker lead-related infective endocarditis makes diagnosis difficult. It must however be suspected in pacemaker patients with low-grade intermittent fever. Transesophageal echocardiography is required. Treatment must combine antibiotic therapy with material extraction.

Endocarditis, Bacterial↗
PubMed2000

[Infective endocarditis related to pacemaker leads. A review].

Infective endocarditis is a rare but serious complication of permanent cardiac pacing with high mortality ranging from 10 to 30%. Clinical symptoms are sometimes acute but more often poor and aspecific in subacute and chronic forms causing prolonged diagnostic delay. In order to make endocarditis on pacemaker leads clearer, we conducted a medline search of all published literature. Analysis of this literature shows that the initial infective source is often local and that Staphylococcus species are the most often pathogens isolated. Clinicians have to search carefully for local inflammatory signs, past or ongoing, and pulmonary embolism because their presence will be helpful for diagnosis. Transoesophageal echocardiography is essential; it shows vegetations in more than 90% and must be repeated when the examination is negative. Treatment has a double goal: a prophylactic treatment in order to reduce risk factors of infection related to implantation of the pacemaker and a curative treatment associating prolonged antibiotic therapy with extraction of the material.

Aged↗
PubMed1999

Comparison of seven RNA extraction methods on stool and shellfish samples prior to hepatitis A virus amplification.

When choosing an extraction method, two parameters have to be considered: recovery of the viral material and elimination or inactivation of inhibitory substances. Seven techniques for extracting hepatitis A virus (HAV) from stool and shellfish samples were compared, in order to identify the protocol most suited to both types of sample and with the best extraction yield. The protocols tested were either techniques for the recovery and purification of total RNA, such as RNAzol, PEG-CETAB, GTC-silica and Chelex, or techniques for isolating specifically HAV using a nucleotide probe or a monoclonal antibody. For stool samples, RNAzol, PEG-CETAB, and magnetic beads with antibody allowed detection of the virus in 11/12 and 12/12 of samples. For shellfish samples, three protocols allowed RNA to be extracted in 90% of cases, RNAzol, PEG-CETAB, and GTC-silica. Their rapidity and low cost make RNAzol and GTC-silica the most suitable for routine diagnostic testing. reserved.

Feces↗
PubMed1999

Quantification of hepatitis A virus in shellfish by competitive reverse transcription-PCR with coextraction of standard RNA.

To quantify hepatitis A virus (HAV) in experimentally contaminated mussels, we developed an internal standard RNA with a 7-nucleotide deletion for competitive reverse transcription (RT)-PCR. Deposited directly into the sample, this standard was used both as extraction control and as quantification tool. After coextraction and competitive RT-PCR, standard and wild-type products were detected by differential hybridization with specific probes and a DNA enzyme immunoassay. The quantifiable range with this reproducible method was 10(4) to 10(7) copies of HAV/gram or 400 to 10(6) 50% tissue culture infective doses/ml.

Animals↗
PubMed1998

Oxidant-antioxidant imbalance in blood of children with juvenile rheumatoid arthritis.

Juvenile rheumatoid arthritis (JRA) is the most commonly diagnosed rheumatic disease in children and may represent not a single disease, but rather a syndrome of diverse aetiologies in which inflammation is an exceedingly complex process. Oxidative free radical production at inflammation sites contributes to tissue damage and could also play a significant role in the pathogenesis of JRA. The aim of this study was to evaluate the antioxidant status and lipid peroxidation parameters related to the clinical form of JRA. Plasma malondialdehyde and hydroperoxide concentrations in children with polyarticular and systemic JRA subtypes were significantly higher than in controls. Plasma vitamin E and beta-carotene levels of the JRA children were lower in the three forms compared with healthy children. Patients with JRA present an imbalance in the oxidant-antioxidant system that manifests clearly in the polyarticular and systemic forms through an increase in lipoperoxidation products and significant decrease in the lipid-soluble antioxidants vitamin E and beta-carotene.

Antioxidants↗
PubMed1998

Interactions between cleaning gobies and territorial damselfish on coral reefs.

We studied the interactions between cleaning gobies, Elacatinus spp., at cleaning stations and territorial dusky damselfish, Stegastes fuscus, on a Barbadian fringing reef to enhance our understanding of the behavioural impact of cleaning stations on members of a coral reef community. Cleaning stations within damselfish territories were visited by significantly fewer species and fewer individuals than those outside damselfish territories. At cleaning stations within damselfish territories, the main client was the territory holder itself. Client behaviour did not differ between the two types of cleaning station; however, cleaning gobies at stations within damselfish territories spent less time cleaning clients, their cleaning bouts were shorter, and their feeding rate on clients was slower. These effects appear to be due to the repeated aggression of territorial damselfish towards fish intruding on to their territories to visit cleaning stations. The overlap between a territorial damselfish and a cleaning station therefore appears to have detrimental impacts on cleaning goby foraging. The presence of cleaning stations within damselfish territories exerted some effects on the territory owners. Although the rates of intrusions were similar on territories with and without cleaning stations, damselfish with cleaning stations tended to chase intruders more often, had a lower foraging rate, and were at higher risk of egg predation because of increased intrusions by egg predators. A potential benefit to territorial damselfish is regular access to a cleaning station; however, the magnitude of this benefit is unknown. This study reveals that damselfish, which are ubiquitous on coral reefs, can generate significant variation in levels of use of cleaning stations, which leads to new questions relating to the settlement behaviour of both cleaning gobies and damselfish. Copyright 1998 The Association for the Study of Animal Behaviour. Copyright 1998 The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed1998

Reverse transcriptase PCR detection of astrovirus, hepatitis A virus, and poliovirus in experimentally contaminated mussels: comparison of several extraction and concentration methods.

Four methods of extraction and three methods of concentration of three enteric viruses from mussels were comparatively evaluated by reverse transcriptase PCR (RT-PCR). Shellfish were experimentally contaminated by immersion in seawater seeded with astrovirus, hepatitis A virus, or poliovirus. Sixty-gram samples of mussel tissues were processed by using borate buffer, glycine solution, saline beef, and saline beef-Freon extraction methods. The viruses were concentrated by precipitation with polyethylene glycol 6000 (PEG 6000) or PEG 8000 or by organic flocculation. RT-PCR was performed with RNA extracts from crude shellfish extracts and concentrates with and without Sephadex LH20 filtration. The glycine solution and borate buffer extraction methods resulted in significantly more RT-PCR-positive samples than the saline beef extraction method. We assessed the efficiency of 20 combinations of extraction and concentration methods. The borate buffer-organic flocculation, borate buffer-PEG 6000, and glycine solution-PEG 6000 combinations gave RT-PCR-positive results for all 27 samples analyzed for the three viruses. Detoxification of the samples by Sephadex LH20 filtration significantly decreased the efficiency of RT-PCR virus detection.

Animals↗
PubMed1998

Simplified reverse transcription polymerase chain reaction procedure with detection by microplate hybridization for routine screening of hepatitis A virus.

Reverse transcription polymerase chain reaction, using either nested or seminested primers, is used extensively for the detection of viruses in small quantities. However, existing methods are prone to false positive reactions. We report here an improved polymerase chain reaction technique based on the use of longer primers (39 nucleotides) with single-step amplification, applied to the detection of hepatitis A in low quantities. While the sensitivity of this technique (10 x the 50% tissue culture infective dose) is equivalent to that of existing methods, it is a simpler procedure, less time consuming, and less susceptible to contamination and therefore provides a more reliable tool for routine diagnosis. Finally, the development of a DNA enzyme immunoassay detection technique and the complete automation of the procedure allow a large number of samples to be processed in clinical laboratories.

Animals↗
PubMed1998

Persistence of infectious hepatitis A virus and its genome in artificial seawater.

The stability of the hepatitis A virus (HAV) genome detectable by RT-PCR in artificial sterile seawater seeded with HAV has been compared to that of HAV detectable in cell culture. The HAV genome was detectable by RT-PCR for 232 days while virus particles were detectable in cell culture for only 35 days. This difference in stability indicates that detection of the HAV genome by RT-PCR is not a reliable indicator of the survival of HAV detectable in cell cultures. However, before these results can be extrapolated to stability in natural seawater, the effect of additional elements in the natural environment, such as bacteria, fungi and suspended matter, on the stability of the HAV genome and cell culture infectious HAV particles, will have to be examined.

Cell Line↗
PubMed1997

[Focal myositis in children. Apropos of a case].

An eleven year old boy presented with localized swelling of the left calf which had been developing for more than 5 years. Another smaller mass was found in the pretibial area. There was an invincible equinus deformity of the foot. Surgical biopsies revealed characteristic histological features of focal myositis showing necrotic and regenerating muscle fibers, randomly distributed, with inflammatory infiltration. An intense fibrotic reaction was observed. This constitutes to our knowledge the first reported case of focal myositis in which development of muscle sclerosis was so important that it was necessary to perform tenotomies one year after excision of the principal tumor in order to restore normal gait. A nearly two-years follow-up does not give evidence of recurrent lesion.

Achilles Tendon↗
PubMed1996

Childhood sclerodermatomyositis: report of a case with the anti-PM/Scl antibody and mechanic's hands.

We report a boy with overlap manifestations of systemic sclerosis and dermatomyositis (sclerodermatomyositis) whose disease showed a changing clinical pattern, and who had mechanic's hands, which are a cutaneous marker of myositis. Serological studies revealed antinuclear antibodies with a homogeneous nucleolar pattern. The anti-PM-Scl antibody was demonstrated by immunoblotting. HLA typing was positive for HLA-DR3/4. After a follow-up period of 11 years, no progression to severe systemic involvement was detected, and aggressive treatment was not administered. The recognition of subsets of patients with homogeneous clinical features and serological markers should permit the recognition of separate conditions among overlap syndromes. This would have prognostic and therapeutic implications.

Antibodies, Antinuclear↗
PubMed1995

Localization of splenic cells with antigen-transporting capability in the chicken.

BACKGROUND: The objective of the present study is to investigate the migration pattern of the splenic dendritic cell of the chicken named the ellipsoid-associated cell (EAC) from the site of initial location at the periphery of the ellipsoid to the splenic T- and B-dependent areas. METHODS: Bovine serum albumin bound to biotin and conjugated to gold particles was used as a histochemically identifiable antigen detected as a peroxidase reaction. The antigen was intravenously injected, and subsequently its pattern of distribution in a time sequence and within the tissue was examined at the light and electron microscopy levels. In addition, an hour prior to sacrifice, the chickens received a single injection of the thymidine analogue 5-bromo-2'-deoxyuridine, in order to quantify the number of DNA synthesizing cells and to establish a relationship between the migrating EAC and the rate of mitosis in the white pulp. RESULTS: The observations showed that between 12 hours and 3 days after the second antigen administration the labeled EAC, which was first located around the ellipsoid, progressively reached further areas with time towards the periarteriolar lymphoid sheaths, where newly formed germinal centers appeared. Furthermore, the rate of cell proliferation within the white pulp was associated with the arrival of the antigen-transporting EAC. CONCLUSIONS: The results suggest that migrating EAC have a role as both antigen-transporting cell and antigen-presenting cell in the T- and B-dependent areas, as a result of which migrating EAC is transiently found in periellipsoidal white pulp, then periarteriolar lymphoid sheaths, and finally germinal centers, where it may function as an interdigitating cell or as a follicular dendritic cell, depending on its location. Thus, we conclude that the EACs are precursors of both interdigitating and follicular dendritic cells.

Animals↗
PubMed1994

Juvenile rheumatoid arthritis of the knee: evaluation with US.

PURPOSE: To evaluate the value of ultrasound (US) in assessing joint inflammation in patients with juvenile rheumatoid arthritis (JRA) of the knee. MATERIALS AND METHODS: US scans obtained in 36 children (mean age, 8 years) with JRA of the knee were compared with those obtained in 30 healthy children. RESULTS: Changes in synovial membrane (synovial thickness), presence of fluid in the suprapatellar bursa, and alterations in the contour (blurring) of the articular cartilage showed statistically significant differences between JRA patients and control subjects. US was more sensitive than physical examination for detecting a minimal amount of intra-articular fluid in 21% of JRA-affected knees with no clinical evidence of active disease. CONCLUSION: US is a simple, rapid, inexpensive, and accurate method for assessing joint inflammation in patients with JRA of the knee.

Adolescent↗
PubMed1993

Pigmented villonodular synovitis of the knee in a patient with Paget's disease of the adjacent femoral bone.

A 49-year-old male patient, diagnosed as having Paget's disease involving the lumbar vertebrae and both femora, felt persistent pain and swelling in the left knee after trauma. A synovectomy was performed. Clinical and histological findings led to the diagnosis of pigmented villonodular synovitis of the knee joint. Only one previous case of this association has been reported. A common aetiology for both diseases is discussed, and traumatic factors should be considered in the aetiology of the association.

Femur↗