Search PubMed⌕ Search

Biomedical subjects

A Kahan

Publications and source records attributed to A Kahan.

At least 55 records · Page 3Linked to original sources
PubMed1999

A leptomeningeal metastasis revealed by sciatica.

UNLABELLED: Meningeal metastatic disease usually occurs as a complication of a brain tumor and is exceptionally isolated in patients with solid tumors. We report the case of a 74-year-old woman admitted for mechanical S1 sciatica refractory to drug therapy. She had been treated for breast cancer three years earlier. Physical findings were pain upon hyperextension of the lumbar spine and absence of the ankle jerks. Analysis of cerebrospinal fluid sampled during an intrathecal glucocorticoid injection showed 1 g/L of protein and 11 normal cells per mm3. Grade 3 L5-S1 spondylolisthesis was seen on plain radiographs, computed tomography scans, and magnetic resonance imaging scans. At that point, the patient developed sphincter dysfunction and motor loss in the left lower limb in the distribution of several nerve roots. Findings were normal from a myelogram and a magnetic resonance imaging study of the brain. A repeat cerebrospinal fluid analysis showed 1.1 g/L of protein and 5 cells/mm3. Because of the discrepancy between the clinical and imaging study findings, the patient was transferred to a neurology department. A third cerebrospinal fluid study showed numerous adenocarcinoma cells, and a repeat magnetic resonance imaging demonstrated a mass in the dural sac opposite L2. A program of monthly intrathecal methotrexate injections was started. A fatal meningeal relapse occurred eight months later. CONCLUSION: This case shows that a leptomeningeal metastasis can cause isolated nerve root pain, and demonstrates the diagnostic value of magnetic resonance imaging and cerebrospinal fluid cytology in patients with atypical symptoms, particularly when there is a history of malignant disease.

Adenocarcinoma↗
PubMed1999

Rheumatic manifestations in patients with thromboangiitis obliterans (Buerger's disease).

OBJECTIVE: To evaluate articular involvement in a large cohort of patients with thromboangiitis obliterans (TAO). METHODS: A retrospective chart review of all patients with TAO admitted to our rheumatology or vascular medicine departments between 1975 and 1995 was undertaken. Patients with a history of osteoarticular involvement were further investigated. This evaluation entailed taking a detailed rheumatologic and musculoskeletal history and physical examination. Laboratory tests and osteoarticular radiographs were obtained. RESULTS: Initial rheumatic manifestations were observed in 11 (12.5%) (7 male/4 female) of 83 (71 male/12 female) patients with TAO. Eight patients presented recurrent episodes of arthralgia, which preceded the diagnosis of TAO by 2 to 13 years (median 10 years). The episodes were monoarticular, acute, transient, and migratory, affected large joints with local inflammatory signs, and were nonerosive. The initial diagnosis often referred to a loco-regional or periarticular problem that tended to recur. There was permanent disappearance of these prodromal rheumatic features with the appearance of ischemic features. Two patients had HLA-B27+ undifferentiated spondyloarthropathies and one presented oligoarthritis. CONCLUSION: TAO should be considered in patients presenting intermittent rheumatism. The key symptoms and signs of the disease should be monitored during the followup period because the first occlusive features may appear more than 10 years later. Thromboangiitis manifestations can thus be similar to systemic vasculitis and connective tissue disease. If the patient is a young adult smoker, particularly a young man with diminished or absent distal pulses, a diagnosis of TAO should be considered.

Adolescent↗
PubMed1999

Nitric oxide synthase is expressed in the lymphomononuclear cells of synovial fluid in patients with rheumatoid arthritis.

OBJECTIVE: To investigate the expression of inducible nitric oxide synthase (iNOS) in subpopulations of peripheral blood and synovial fluid (SF) leukocytes in patients with rheumatoid arthritis (RA). METHODS: iNOS was detected in peripheral blood and SF samples after cell permeabilization, by 2 color immunofluorescence flow cytometry. Samples from 14 patients with RA and 8 with osteoarthritis (OA) were studied. Nitrite concentration was determined by Griess reaction, interleukin 1beta and tumor necrosis factor alpha by an immunoenzymatic assay, and C-reactive protein (CRP) by an immunonephelometric method. RESULTS: In SF, iNOS was detected in 11 of 14 patients with RA and 2 of 8 with OA. In blood cells, iNOS was detected in 8 of 14 patients with RA and none of the OA group. iNOS was consistently detected in monocytes and was not detected in granular cells. In RA, there was no correlation between the number of iNOS positive mononuclear cells and cytokine concentrations. CRP concentration was correlated with the number of iNOS positive mononuclear cells in RA SF samples. CONCLUSION: SF mononuclear cells from patients with RA express iNOS and are involved in NO production in the joint. The number of positive cells is correlated with CRP concentration, suggesting the implication of NO production in the inflammatory process.

Adult↗
PubMed1998

[Desmoid tumor of the thoracic wall. A case manifesting as painful stiffness of the shoulder].

BACKGROUND: Desmoid tumors are uncommon fibromatous tumors arising from musculoaponeurotic tissue characterized by spindle cell fibroblast and myofibroblast proliferation. The cause is unknown (trauma, hormonal factors, genetic anomaly...). Locally invasive, they tend to recur increasing morbidity or even mortality. CASE REPORT: Stiff shoulder resulting from blockage of the scapulothoracic articulation was the inaugural sign. Three-phase bone scintigraphy demonstrated early uptake in the soft tissue in contact with the scapula. Magnetic resonance imaging and biopsy confirmed the diagnosis of desmoid tumor. Complete resection was performed. No adjuvant radiotherapy nor hormone treatment were given since no antiestrogen receptor antibodies were identified on the surgical specimen. DISCUSSION: The clinical manifestation (stiff shoulder) and the scapular localization observed in this case are unusual for desmoid tumors. Initially tendinopathy of the shoulder, acromio-clavicular arthropathy and capsular retraction of the shoulder joint had been entertained. Early diagnosis and wide surgical resection are indicated in desmoid tumors.

Adult↗
PubMed1998

Gastrointestinal tolerability of meloxicam compared to diclofenac in osteoarthritis patients. International MELISSA Study Group. Meloxicam Large-scale International Study Safety Assessment.

Although widely used, non-steroidal anti-inflammatory drugs (NSAIDs) are associated with a high incidence of gastrointestinal (GI) side-effects. Inhibition of the cyclooxygenase (COX) enzyme is the basis for both the efficacy and toxicity of NSAIDs. The discovery of two COX isoforms, constitutive COX-1 and inducible COX-2, has led to the hypothesis that selective inhibition of COX-2 will minimize the potential for GI toxicity without compromising efficacy. The Meloxicam Large-scale International Study Safety Assessment (MELISSA) trial reported here was therefore set up to investigate the tolerability of meloxicam, a preferential inhibitor of COX-2, compared to diclofenac. MELISSA was a large-scale, double-blind, randomized, international, prospective trial, conducted over 28 days in patients with symptomatic osteoarthritis. Patients received either meloxicam 7.5 mg or diclofenac 100 mg slow release, the recommended doses for the treatment of osteoarthritis. Evaluation of the profile of adverse events was the main aim of the trial, together with assessment of efficacy. A total of 9323 patients received treatment (4635 and 4688 in the meloxicam and diclofenac groups, respectively). Significantly fewer adverse events were reported by patients receiving meloxicam. This was attributable to fewer GI adverse events (13%) compared to diclofenac (19%; P < 0.001). Of the most common GI adverse events, there was significantly less dyspepsia (P < 0.001), nausea and vomiting (P < 0.05), abdominal pain (P < 0.001) and diarrhoea (P < 0.001) with meloxicam compared to diclofenac. Five patients on meloxicam experienced a perforation, ulcer or bleed vs seven on diclofenac (not significant). No endoscopically verified ulcer complication was detected in the meloxicam group compared to four with diclofenac. There were five patient days of hospitalization in patients on meloxicam compared to 121 with diclofenac. Adverse events caused withdrawal from the study in 254 patients receiving meloxicam (5.48%) compared to 373 (7.96%) on diclofenac (P < 0.001). These differences were attributable to differences in reported GI adverse events (3.02% on meloxicam vs 6.14% on diclofenac; P < 0.001). Differences in efficacy, as assessed by visual analogue scales, consistently favoured diclofenac. In all instances, 95% confidence intervals did not cross zero, suggesting a statistically significant effect. However, differences were small (4.5-9.01% difference) and did not reach pre-determined levels of clinical significance. Nevertheless, significantly more patients discontinued meloxicam because of lack of efficacy (80 out of 4635 vs 49 out of 4688; P < 0.01). The MELISSA trial confirms earlier studies suggesting that meloxicam has a significantly improved GI tolerability profile in comparison with other NSAIDs, including diclofenac. These results may in part reflect the preferential COX-2 selectivity of meloxicam, although the dose and other aspects of tolerability may be important. These results may provide support for the hypothesis that selective inhibition of COX-2 relative to COX-1 might be an effective approach towards improved NSAID therapy.

Aged↗
PubMed1998

Improvement in gastrointestinal tolerability of the selective cyclooxygenase (COX)-2 inhibitor, meloxicam, compared with piroxicam: results of the Safety and Efficacy Large-scale Evaluation of COX-inhibiting Therapies (SELECT) trial in osteoarthritis.

SELECT is a large-scale, prospective, international, multicentre, double-blind, double-dummy, randomized, parallel-group trial. Patients with exacerbation of osteoarthritis were treated with the recommended dose of meloxicam (7.5 mg) or piroxicam (20 mg) once daily for 28 days; 4320 patients were administered meloxicam and 4336 piroxicam. The incidence of adverse events was significantly lower in the meloxicam group (22.5%) compared with the piroxicam group (27.9%; P < 0.001), mainly due to the significantly lower incidence of gastrointestinal (GI) adverse events in the meloxicam than in the piroxicam group (10.3% vs 15.4%,; P < 0.001), while the efficacy of both drugs was equivalent. Individual GI events occurred significantly less often with meloxicam than piroxicam: dyspepsia (3.4% vs 5.8%; P < 0.001), nausea/vomiting (2.5% vs 3.4%; P < 0.05) and abdominal pain (2.1% vs 3.6%; P < 0.001). There were 16 patients with perforations, ulcerations or bleeding (PUBs) of the upper GI tract in the piroxicam group compared with seven in the meloxicam group (relative risk piroxicam:meloxicam = 1.4). Four PUBs were complicated (perforations or bleedings); none of these occurred in the meloxicam group (relative risk piroxicam:meloxicam = 1.9). The outcome of SELECT is consistent with that of the large-scale clinical trial of similar design and size which compared 7.5 mg meloxicam with 100 mg diclofenac in patients with osteoarthritis, and with a previous global analysis of the safety of meloxicam. It adds further data to the proposed relationship between selective inhibition of cyclooxygenase-2 and improved GI tolerability of non-steroidal anti-inflammatory drugs.

Aged↗
PubMed1998

Chronic intestinal pseudo-obstruction in systemic lupus erythematosus.

BACKGROUND/AIMS: Chronic intestinal pseudo-obstruction (CIPO) reflects a dysfunction of the visceral smooth muscle or the enteric nervous system. Gastrointestinal manifestations are common in systemic lupus erythematosus (SLE) but CIPO has not been reported. Features of CIPO are reported in five patients with SLE. METHODS: From 1988 to 1993, five patients with SLE or SLE-like syndrome were hospitalised for gastrointestinal manometric studies. CIPO was the onset feature in two cases. Antroduodenal manometry (three hours fasting, two hours fed) was performed in all patients, and oesophageal manometry in four. RESULTS: Intestinal hypomotility associated with reduced bladder capacity and bilateral ureteral distension was found in four patients and aperistalsis of the oesophagus in three. Treatment, which consisted of high dose corticosteroids, parenteral nutrition, promotility agents, and antibiotics, led to remission of both CIPO and urinary abnormalities in all cases. Antroduodenal manometry performed in two patients after remission showed increased intestinal motility. One patient died, and postmortem examination showed intestinal vasculitis. CONCLUSIONS: CIPO in SLE is a life threatening situation that can be reversed by treatment. It may be: (a) a complication or onset feature of the disease; (b) secondary to smooth muscle involvement; (c) associated with ureteral and vesical involvement; (d) the result of intestinal vasculitis.

Adult↗
PubMed1998

[Primary ureteral amyloidosis].

OBJECTIVE: Two additional cases of primary ureteral amyloidosis are described. The current literature and clinical classification of the disease are reviewed. METHODS: Over a period of 18 months, we observed two cases of organic ureteral stenosis whose etiology was difficult to determine. The first case warranted a nephroureterectomy due to the condition of the compromised urinary tract. Analysis of the surgical specimen showed histological evidence of ureteral amyloidosis. In the second case, the previous experience allowed a preoperative diagnosis to be made, an exceptional situation that permitted conservative surgery. Characterization of the amyloid proteins was done in both cases with immunochemical study by Western Blot. RESULTS: Two patients with primary ureteral amyloidosis were surgically treated. The first case underwent complete excision of the urinary tract. The second case, who had a single kidney, was treated by conservative surgery. In both cases we identified a fragment of the lambda light chain of immunoglobulin by Western Blot characterization as previously reported in localized amyloidosis. CONCLUSIONS: Although ureteral amyloidosis is an infrequent disease, it should be seriously considered in the differential diagnosis of organic ureteral stenosis in order to avoid unnecessary excision. To our knowledge, these are the first cases of ureteral amyloidosis with immunochemical characterization of the amyloid protein.

Aged↗
PubMed1997

Detection of membrane associated thioredoxin on human cell lines.

Thioredoxin (TRX) is a ubiquitous dithiol-oxidoreduction enzyme broadly expressed in cells from prokaryote to eukaryote organisms. Human thioredoxin (human TRX) gene, previously cloned in our laboratory, codes for a 12-kDa protein found in the culture supernatant of several hemopoietic human cell lines. This protein is secreted by a nonclassical pathway. The role of the secreted enzyme as a signalling soluble mediator was demonstrated, but nothing is known about a membrane associated form of thioredoxin which could be involved in cell/cell contacts and accessory signal function. Thus, we performed experiments to determine if human TRX is also expressed at the cell surface. We report here positive results based upon indirect immunofluorescence flow cytometric analysis of different human cell lines (HeLa, U 937, Jurkat, 3B6, Daudi and Raji) using a cross reactive sheep anti E. coli TRX polyclonal antibody demonstrating a significant expression of human TRX at the surface of human cells.

Animals↗
PubMed1996

Multifocal stenosing ulcerations of the small intestine revealing vasculitis associated with C2 deficiency.

A patient with cryptogenic multifocal ulcerous stenosing enteritis characterized by repeated bouts of intestinal obstruction, ulcerative stenosis of the small bowel relapsing after surgical resection, and steroid sensitivity is described. Fourteen strictures of the jejunum were found at laparotomy. Despite resection, abdominal pain persisted. Steroid therapy was effective but led to dependence. In our patient, cryptogenic multifocal ulcerous stenosing enteritis was associated with fever, asthma, Raynaud's phenomenon, sicca syndrome, heterozygous type I C2 deficiency (28-base pair gene deletion), stenosis, and aneurysms in selective mesenteric angiography. It is hypothesized that cryptogenic multifocal ulcerous stenosing enteritis might be related to a particular form of polyarteritis nodosa with mainly intestinal expression or to a yet unclassified independent vasculitis.

Adult↗
PubMed1996

The use of antimalarials in combination with other disease modifying agents in rheumatoid arthritis--the French experience.

A significant proportion of patients with rheumatoid arthritis have an aggressive, severe disease that may contribute to excess mortality. It has been suggested that early, aggressive therapy might improve the prognosis of these patients with active, severe rheumatoid arthritis. Combinations of disease modifying anti-rheumatic drugs including antimalarials are increasingly used in patients with active disease. While several open trials showed encouraging results, some controlled studies gave less support for the use of combination therapy. Ongoing controlled trials of double or triple combination therapy, such as hydroxychloroquine, methotrexate and sulphasalazine, should help define its place in treating patients with rheumatoid arthritis.

Antimalarials↗
PubMed1996

[Attempt at preventing hyperacute xenogenic rejection by isotopic suppression of IgM in the recipient].

Hyperacute xenogeneic rejection is partly initiated by the binding of performed natural antibodies on the recipient's vascular endothelium. In this study, isotypic suppression of IgM in the recipient was conducted in the guinea pig-to-rat combination. Anti-IgM HIS 40 and 56 monoclonal antibodies were injected intraperitoneally in rats (n = 3) (Group 1). Control animals were rats (n = 13) treated by PBS (Group 2). Guinea pig hearts were implanted heterotopically in all rats. Depletion of circulating IgM in the recipient was assessed by ELISA. The circulating and splenic B-lymphocyte population was scanned by FACS analysis. Isotypic suppression was very effective for the depletion of circulating IgM in Group 1 rats (alpha < 0.01) as assessed by ELISA. Similarly, the rate of circulating and splenic B-lymphocytes was significantly decreased in treated animals (alpha < 0.01). However, the graft survival in Group 1 (14 +/- 6.9 min) was not different from that observed in Group 2 (15.4 +/- 5 min). Isotypic suppression of IgM in the recipient did not delay hyperacute xenogenic rejection in the guinea pig-to-rat combination. The prevention of hyperacute rejection must therefore be based on the various mechanisms of this phenomenon.

Acute Disease↗
PubMed1994

Ketoprofen and prednisolone do not modulate neutrophil CR1, CR3 and Fc gamma RIII expression in healthy volunteers.

We assessed the effect of ketoprofen and prednisolone on the complement receptors (CR1 and CR3) and Fc gamma RIII expression on polymorphonuclears in an ex vivo study, using a randomized, single-blind, placebo-controlled, parallel design. Twenty-four healthy, male, Caucasian volunteers received either oral ketoprofen 100 mg twice daily, or prednisolone 5 mg twice daily, or placebo twice daily for 7.5 days. CR1, CR3 and Fc gamma RIII on unstimulated and FMLP-, C5a-, LTB4-, and GM-CSF-stimulated neutrophils were assessed using specific monoclonal antibodies and flow cytometry. No statistically significant drug effect was found for CR1, CR3, and Fc gamma RIII expression on polymorphonuclears. An in vitro study also yielded negative results. These findings do not support the hypothesis that the effect of non-steroidal antiinflammatory drugs on neutrophils is due to CR1, CR3, or Fc gamma RIII modulation.

Administration, Oral↗
PubMed1994

Phenotype and functional profile of T cells expressing gamma delta receptor from patients with active Behçet's disease.

OBJECTIVE: Our aim was to investigate the TCR gamma delta+ subset in Behçet's disease (BD) inflammatory sites, which better reflects changes associated with the pathologic process than peripheral blood. METHODS: Forty-five patients with active BD, 10 patients with recurrent aphthous ulcers, 12 patients with rheumatoid arthritis, 5 patients with noninflammatory neurologic diseases and 15 healthy individuals were studied. Three monoclonal antibodies TCR delta 1, BB3, and A13 were used to assess the percentage of TCR gamma delta+ in peripheral blood mononuclear cells (PBMC), in bronchoalveolar lavage and cerebrospinal fluid (CSF). CD11a/CD18 was used to study adhesion molecules. TCR gamma delta+ cells isolated by immunomagnetic separation were tested for cytolytic activity against K562 target cells after interleukin 2 stimulation. RESULTS: The PBMC TCR gamma delta BB3+ subset was significantly increased in BD. In BD inflammatory sites, TCR gamma delta+ cells were also present, composed mainly of A13+ cells from these sites also expressed CD11a marker. TCR gamma delta+ cells from inflammatory sites displayed a higher cytotoxic activity than controls, mediated by the A13+ subset. CONCLUSION: The accumulation of cytotoxic TCR gamma delta+ cells at the sites of inflammation suggests their involvement in the local injury process.

Adult↗
PubMed1993

Target antigens of hyperacute xenogeneic rejection in the rat to guinea pig to rat discordant combinations.

The increasing shortage in allografts has led to a renewed interest in xenogeneic transplantation. Discordant combinations are characterized by hyperacute rejection partly due to the presence of natural antixenogeneic antibodies in the recipient. The aim of this work was to characterize the target antigens, using 2 discordant models. In the rat into guinea pig model, analysis of organ homogenates by immunoblotting revealed numerous bands. Some of these bands were organ specific, whereas others, namely in the 55-kDa region, were detected in liver, heart, lung, and kidney. Using membrane extracts of liver cells or of aortic endothelial cells, only bands of 55 kDa were revealed. No band could be seen using extracts of isolated hepatocytes. Two bands of 55 kDa disappeared after preabsorption of guinea pig sera on the various rat tissue homogenates, suggesting that they represent xenoantigens common to these tissues. In order to investigate the in vivo relevance of these 55-kDa antigens, isolated rat livers were perfused with decomplemented guinea pig sera. Eluates revealed one single print of 55 kDa on rat tissue homogenates. Finally, preincubation of rat mononuclear cells with various xenogeneic sera did not inhibit the binding of mAb specific for rat class I or class II MHC antigens, suggesting that the latter are not recognized by natural xenoantibodies. In the guinea pig to rat model, the antigens detected had a molecular mass ranging from 95 to 110 kDa. Absorption and perfusion experiments also showed that these antigens were common to various tissues and involved in the binding of rat natural antibodies ex vivo. In conclusion, our results indicate that rat xenoantigens of about 55 kDa are recognized by guinea pig natural antibodies, while guinea pig xenoantigens of 95-110 kDa are bound by rat natural antibodies. These antigens are common to liver, heart, lung, and kidney, are borne by endothelial cells, and cannot be found on hepatocytes.

Acute Disease↗
PubMed1993

Lack of effect of phenobarbital on ex vivo leukocyte oxidative metabolism in healthy volunteers.

Oxidative metabolism in activated human polymorphonuclears catabolizes leukotriene B4 by a cytochrome P450 omega-hydroxylase and procainamide by a myeloperoxidase. The percentage of leukotriene B4 metabolized by activated human polymorphonuclears and the apparent enzymatic parameters of procainamide metabolism were studied ex vivo in six healthy volunteers before and after phenobarbital intake (100 mg/day) for 10 days and in six healthy control volunteers. No differences were found between groups for the difference in percentage of leukotriene B4 metabolized between day 11 and day 1. The apparent enzymatic parameters, Km and Vm, of procainamide oxidation did not differ significantly between the groups both on day 1 and day 11. These results do not show any evidence of inducibility of leukotriene B4 and procainamide metabolism in human polymorphonuclears. However, a positive correlation between 6 beta OH-cortisol excretion and percentage of leukotriene B4 metabolized was observed on day 11. This study suggests that human polymorphonuclears cytochrome P450 leukotriene B4 omega-hydroxylase and procainamide metabolism is not a useful method to study cytochrome P450 induction in clinical pharmacology.

17-Hydroxycorticosteroids↗