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J Font

Publications and source records attributed to J Font.

At least 163 records · Page 9Linked to original sources
PubMed1995

The effect of systemic lupus erythematosus and long-term steroid therapy on bone mass in pre-menopausal women.

The aim of our study was to assess bone mineral density (BMD) in pre-menopausal women with systemic lupus erythematosus (SLE) and the influence of disease activity and use of corticosteroids. Lumbar and femoral BMD were measured in 43 patients with SLE (28 on regular steroid therapy, 15 with recent onset, non-treated) and compared with 43 healthy women matched for age. In addition, 21 SLE patients treated with corticosteroids were followed-up with a mean of 36.6 +/- 12.7 months. BMD was significantly lower in SLE patients with prednisone doses > or = 7.5 mg/day than those of recent onset (lumbar: 1.07 +/- 0.11 vs 1.15 +/- 0.13, P = 0.039; femur: 0.85 +/- 0.13 vs 0.98 +/- 0.21, P = 0.034) and the control group (lumbar: 1.07 +/- 0.11 vs 1.13 +/- 0.10, P = 0.040; femur: 0.85 +/- 0.13 vs 0.93 +/- 0.10, P = 0.028). In addition, 18% of SLE steroid users had osteoporosis. Lumbar and femoral BMD were inversely correlated with the time of treatment and the cumulative doses of prednisone. There were no significant BMD changes during the 3-yr follow-up period. In conclusion, in SLE pre-menopausal patients lumbar and femoral BMD is decreased and related to long-term corticosteroid therapy.

Adult↗
PubMed1995

Lack of relationship between human immunodeficiency virus infection and systemic lupus erythematosus.

The objective of this work was to determine whether HIV-1 and HIV-2 could be involved in the pathogenesis of systemic lupus erythematosus (SLE). Seventy-five consecutive Caucasian patients with SLE presenting at one institution over a 2-year period were studied. Serum samples were surveyed for anti-HIV-1 antibodies by a commercial ELISA coated with HIV-1-p24. For confirmation, conventional immunoblots were performed with the following antigens: HIV-1-gp41, p31, p24 and p17 (recombinant) and HIV-2-gp36 (synthetic peptide). Additionally, Western blots with HIV-1-gp160, gp120, gp41, p65, p51, p24 and p18 bands were applied. Seventeen (23%) patients exhibited reactivity with HIV-1-p24 in the ELISA, but in the immunoblots and Western blots these sera samples were negative. Patients with SLE may exhibit a reactivity with HIV-1-p24 in the ELISA for HIV infection screening but not in the confirmatory blots. This false-positive reactivity is probably due to molecular mimicry between autoantigens and retroviruses or a contaminant or artefacts in the antigen preparation procedure.

Acquired Immunodeficiency Syndrome↗
PubMed1995

When does amyloidosis complicate systemic lupus erythematosus?

Secondary amyloidosis is a well recognised complication of rheumatic diseases, but the association with systemic lupus erythematosus is very unusual. We report the case of a patient with systemic lupus erythematosus who developed proteinuria due to renal amyloidosis. We also review the cases previously reported and the hypothesis on the pathogenic mechanisms.

Adult↗
PubMed1995

Development of polyarteritis nodosa in the course of inactive systemic lupus erythematosus.

A 63-year-old woman developed a clinical and pathological picture of polyarteritis nodosa (PAN). Systemic lupus erythematosus (SLE) had been diagnosed 12 years previously, and she had been symptom and therapy-free for a decade. Development of 'primary' systemic vasculitis in SLE patients has rarely been described previously and the significance of this association remains unclear. The possible explanation for this transition from one connective tissue disease to another is discussed.

Female↗
PubMed1995

Effect of plasma from patients with primary antiphospholipid syndrome on platelet function in a collagen rich perfusion system.

The effect on platelet function of plasma from 9 patients with primary antiphospholipid syndrome (PAS) with previous thrombotic episodes was investigated under flow conditions. Five asymptomatic individuals with antiphospholipid antibodies (aPL) (A-aPL) and 14 normal controls were also studied. Patients and controls plasmas were added (1:20 v/v) to anticoagulated blood and perfused through annular chambers containing collagen rich vessel segments. The interaction of platelets with vessel subendothelium was morphometrically evaluated in thin sections. An increase in both covered surface and thrombi formation was observed in perfusions in the presence of PAS-plasma (mean +/- SD: 34.2% +/- 9.6% and 23.2% +/- 10.0% respectively) compared with control plasmas (21.4% +/- 7.3% and 10.1% +/- 7.7%, p < 0.01). Affinity purified anticardiolipin antibodies from one PAS patient showed a similar effect when added to normal blood. In contrast, A-aPL plasma had no effect on platelet-subendothelium interaction. In parallel studies, the same plasmas were incubated with isolated normal platelets before and after activation with ADP or collagen and the binding of immunoglobulins (Ig) was determined by flow cytometry. A significantly increased binding of Ig was observed in 8 out of 9 plasmas from PAS patients when platelets had been activated with collagen but not when resting or ADP activated platelets were used. No increased Ig binding to platelets was seen using A-aPL individuals plasma. These observations might help to explain the pathophysiology of the thrombotic events occurring in patients with PAS.

Adult↗
PubMed1995

Occurrence of antineutrophil cytoplasmic and antineutrophil (peri)nuclear antibodies in rheumatoid arthritis.

OBJECTIVE: To elucidate whether sera from patients with rheumatoid arthritis (RA) contain antineutrophil cytoplasmic antibodies (ANCA) or granulocyte specific antinuclear antibodies (GS ANA), or both, and to analyze possible correlations with different clinical and laboratory data. METHODS: Forty-seven consecutive outpatients with RA were included. Control sera were obtained from patients with well defined rheumatic diseases and from healthy individuals. Serum samples were examined by indirect immunofluorescence (IIF) on both ethanol and paraformaldehyde fixed neutrophils and by ELISA using as substrates myeloperoxidase (MPO), proteinase 3, and a purified extract of alpha-granules. ANA were detected by IIF using cultured HEp-2 cells. RESULTS: Twenty-three patients (49%) had a perinuclear pattern (p-ANCA) by ethanol fixation, of which only 2 became cytoplasmic on paraformaldehyde fixed cells. These 2 patients also had a positive myeloperoxidase ELISA, while none of the remaining 45 had a positive result from the 3 ELISA performed. All 21 patients (45%) with a p-ANCA pattern that was not modified by paraformaldehyde fixation had a specific immunostaining upon examination at high power magnification; we termed this GS ANA specific pattern. The specificity of this pattern was further confirmed by a doubled blind test performed by 2 independent observers. In our study, all GS ANA pattern positive sera fulfilled the previously known definition of these antibodies. We found no relationship between GS ANA and variables such as disease duration and activity, rheumatoid factor, and vasculitis. Notably, 2 RA patients with "true" ANCA (anti-MPO antibodies) had an associated pulmonary-renal syndrome (microscopic polyangiitis). CONCLUSION: Most p-ANCA in our series of patients with RA did not seem to correspond to "true" ANCA but to antibodies directed against nuclear or perinuclear antigenic constituents of the neutrophils (GS ANA). The observation of their distinctive and specific immunostaining pattern, when screening patients for the presence of ANCA by IIF, may alert us to the possible presence of RA.

Adult↗
PubMed1994

[Primary antiphospholipid syndrome: clinical and biological study of 36 cases].

BACKGROUND: The aim of this study was to analyze the clinical and biological characteristics and follow up in a series of patients with the primary antiphospholipid syndrome. METHODS: Thirty-six patients were prospectively studied. The antiphospholipid antibodies were determined with the following techniques: IgG and IgM anticardiolipin antibodies by ELISA, lupic anticoagulant by coagulometric tests and serology of syphilis by a reaginic test. RESULTS: The mean age of the patients was of 29.9 years with a female/male relation of 4.1 to 1. The most frequently observed clinical manifestations were miscarriage and fetal death in a total of 22 patients (61%). Thrombotic phenomena were observed in 15 patients (42%) with predominance of venous thrombosis of the deep venous system of the limbs and pulmonary embolism. Thrombocytopenia was detected in 9 cases (25%), autoimmune hemolytic anemia in 3 (8%) and low or moderate titres of antinuclear antibodies in 12 (33%). Other infrequent clinical manifestations were cardiac valve lesions, livedo reticularis and epilepsy. Three patients (8%) had relatives with systemic lupus erythematosus. The antiphospholipid antibody study demonstrated the presence of anticardiolipin antibodies in 28 patients (78%), lupic anticoagulant in 22 (67%) (not determined in 3 patients) and falsely positive test for syphilis in 5 (14%). Patients with thrombosis received anticoagulant therapy, with all evolving favorably except two who died (multiple pulmonary thromboembolism in one case and cerebral hemorrhage in the other) mortality of the series thus being 5.6%. Fourteen women wished to become pregnant following fetal loss and were treated with acetylsalicylic acid in 3 cases together with prednisone (15 to 30 mg/day) with successful pregnancies being achieved in 12 cases (86%). CONCLUSIONS: The primary antiphospholipid syndrome is a well differentiated clinical entity and the presence of antiphospholipid antibodies should be investigated in young people presenting thrombosis or fetal loss for no apparent reason.

Abortion, Spontaneous↗
PubMed1994

[Neutrophil anticytoplasmic antibodies: their diagnostic utility in vasculitis and glomerulonephritis].

BACKGROUND: The prevalence and diagnostic usefulness of antineutrophil cytoplasmic antibodies (ANCA) were analyzed in a series of patients with different types of vasculitis, connective tissue diseases, nephropathies and lung diseases. METHODS: Six hundred seventy-six consecutive patients with systemic vasculitis, connective tissue diseases, nephropathies and different lung disturbances were included in the study. The ANCA were determined by indirect immunofluorescence (IIF) on neutrophils fixed in ethanol. For the detection of antimyeloperoxidase (MPO) antibodies (Ab) a new technique was developed consisting in the performance of IIF on neutrophils with a deficiency in MPO. The serologic samples were also analyzed by enzyme-linked immunosorbent assays with MPO and purified proteinase 3 (PR3). RESULTS: ANCA were demonstrated in 95 patients. A cytoplasmic pattern (c-ANCA) was detected in 25 cases (26%) and in 70 (74%) a perinuclear pattern (p-ANCA) was observed. Twenty-one of the 25 cases (84%) of c-ANCA corresponded to anti-PR3 Ab and 61 of the 70 (87%) of p-ANCA corresponded to anti-MPO Ab. The anti-PR3 Ab identified Wegener's granulomatosis, with a sensitivity and specificity for the generalized and clinically active forms being 65 and 88%, respectively. The anti-MPO Ab were principally detected in patients with rapidly progressive glomerulonephritis (RPGN) and hemorrhagic alveolar capillaritis. The sensitivity and specificity of the anti-MPO Ab for the RPGN and alveolar capillaritis were 75% and 98%. CONCLUSIONS: Two principal subtypes of ANCA may be detected, which also recognize two fundamental clinicopathologic entities. The high diagnostic sensitivity and specificity of these antibodies for each of the processes to which they are associated can justify the adoption of therapeutic measures in determined cases.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1994

Responsiveness of T lymphocytes from systemic lupus erythematosus to signals provided through CD26 antigen.

To investigate whether the T cell defective capacity to proliferate observed in systemic lupus erythematosus (SLE) T cells is a possible consequence of an intrinsic T cell disorder, the integrity of the accessory activation pathway mediated through CD26 antigen in SLE T cells was studied. Hyporesponsiveness of peripheral blood mononuclear cells (PBMC) from SLE to PHA and CD26 Mab was observed and no differences were found when the responsiveness of highly purified T cells to IL-2, IL-2 plus CD26 Mab, phorbol 12-myristate 13-acetate (PMA), or when PMA plus CD26 Mab was analyzed. Findings suggest that signals induced by triggering CD26 are not intrinsically altered in SLE T cells. However, some alteration of the regulatory involvement of monocytes or B cell over T cell function may be involved.

Adult↗
PubMed1994

A new three-dimensional culture of human keratinocytes: optimization of differentiation.

Many attempts have been made to obtain reconstructed human epidermis comprised of keratinocytes and extracellular-matrix constituents (essentially collagen) in the presence or absence of fibroblasts. A simple model of cultured human keratinocytes, grown at the air-liquid interface of a noncoated artificial membrane, has been developed. This culture system offers many advantages: easy control of environmental factors and routine examination using optical or electronic microscopy, immunohistochemistry and indirect immunofluorescence techniques. This model enables the analysis of well-known differentiation markers and also integrins, a family of cell-surface molecules involved in cell-cell and cell-extracellular matrix interactions, whose receptors are expressed on all basal keratinocytes. In our culture system, the expression of the different integrin subunits (alpha 2, alpha 3, alpha 5, alpha 6, beta 1) was studied as a function of the differentiation state in two different media (K-SFM or DMEM/Ham's F12) supplemented with 5% fetal calf serum and adjusted to 1.5 mmol/L calcium. The most significant data are the preponderant expression of the alpha 2 and alpha 3 subunits in the basal and suprabasal layers, with membrane expression differing according to the culture medium; terminal differentiation was obtained in DMEM/Ham's F12. The use of membrane inserts represents a significant technological advance in culturing keratinocytes and is an easy-to-handle and valid model for determining the influence of physiological or pharmacological factors on cell proliferation or differentiation.

Cell Adhesion↗
PubMed1994

Influence of fibroblasts on epidermization by keratinocytes cultured on synthetic porous membrane (insert) at the air-liquid interface.

Culture of keratinocytes on a noncoated porous synthetic membrane maintained at the air-liquid interface allows the establishment of a fibroblast/keratinocyte co-culture, without direct cell-cell contact between the two cellular layers. The influence of fibroblasts (proliferating, confluent or blocked by mitomycin C) on epidermization (i.e., expression of integrins and markers of epidermal differentiation) was studied by immunohistochemistry in two culture media. In the medium supplemented with FCS or Ultroser G and in the absence of fibroblasts, alpha 2, alpha 3, alpha 5 and alpha 6 subunits of integrins are expressed by the basal keratinocytes, except alpha 5 which does not appear with the medium supplemented with Ultroser G. During stratification, the alpha 3 subunit is the only one to persist on suprabasal cells and all the markers of epidermal differentiation studied (filaggrin, involucrin, transglutaminase, keratins K1/K10) are expressed at the 14th day of emerged culture. The presence of fibroblasts modifies the expression profile of integrins: when they are proliferative, the expression of alpha 2 and alpha 6 chains is delayed in the medium supplemented with FCS, and the alpha 6 chain is absent in the medium supplemented with Ultroser G; when they are confluent or blocked by mitomycin C, greater changes are observed only in the medium supplemented with Ultroser G and lead to inhibition or delay of the expression of alpha 2 and alpha 6.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell Communication↗
PubMed1994

Comparison of the primary and secondary antiphospholipid syndrome: a European Multicenter Study of 114 patients.

PURPOSE: To determine whether the features of the antiphospholipid syndrome (APS) are in any way influenced by the presence or absence of systemic lupus erythematosus (SLE). We followed up patients with 'primary' APS (PAPS) and APS secondary to SLE (APS plus SLE) with the objective of comparing laboratory and clinical events and of determining whether patients with PAPS would have evolution to SLE. PATIENTS AND METHODS: A total of 114 patients from 3 European referral centers were included in this study. Fifty-six had APS plus SLE and 58 had PAPS. Laboratory and clinical data were collected during an average 2-year period. RESULTS: Patients with PAPS and patients with APS plus SLE had similar clinical and laboratory profiles, with the exceptions of autoimmune hemolytic anemia, endocardial valve disease, neutropenia, and low C4 levels, all of which occurred more frequently in patients with APS plus SLE (p values: < 0.05, < 0.005, < 0.01, and < 0.001, respectively). On follow-up, 10 thrombotic episodes occurred in 10 patients, 8 of whom were receiving anticoagulant therapy. No patient with PAPS had either anti-DNA or anti-extractable nuclear antigen antibodies, and these patients had a significantly lower prevalence of antinuclear antibodies (41%) than patients with APS plus SLE (89%). CONCLUSIONS: Patients with APS plus SLE and PAPS have similar clinical profiles, although heart valve disease, hemolytic anemia, low C4 levels, and neutropenia seem to be more common in patients with APS plus SLE. Patients with APS may develop further thrombotic events despite anticoagulation therapy.

Adult↗
PubMed1994

Antibodies to endothelial cells in Behçet's disease: cell-binding heterogeneity and association with clinical activity.

OBJECTIVES: To investigate the prevalence and characteristics of antibodies to endothelial cells (aEC) from large vessel and from microvasculature in a group of patients with Behçet's disease (BD) to determine the relationship of these antibodies with clinical and laboratory features of the disease. METHODS: Thirty patients with BD were prospectively and consecutively studied. The aEC were determined by enzyme-linked immunosorbent assay (ELISA) using endothelial cells derived from human umbilical vein (large vessel) as well as from retroperitoneal adipose tissue (microvasculature). RESULTS: Fifteen patients (50%) had aEC, either directed to large vessel [8(26%) patients] or microvascular [13(43%) patients] endothelial cells. The percentage of active patients was significantly higher in the aEC-positive group [12(80%) patients] compared with the aEC-negative group [5(33%) patients] (p < 0.05). CONCLUSIONS: Patients with BD have a high prevalence of aEC when microvascular endothelial cells are used in the assay. These antibodies seem to be a marker of disease activity in this condition, previously considered as negative for autoantibodies.

Adipose Tissue↗
PubMed1994

Antineutrophil cytoplasmic autoantibody-associated alveolar capillaritis in patients presenting with pulmonary hemorrhage.

The objective of this study was to determine the significance of the antineutrophil cytoplasmic autoantibodies (ANCAs) from the clinicopathologic viewpoint of pulmonary hemorrhage occurring as a prominent event of disease. Forty-three consecutive patients with both pulmonary hemorrhage as a prominent clinical manifestation and a positive test for antineutrophil cytoplasmic autoantibodies were studied. Thirty-six patients underwent open lung biopsy, including histologic, tissue immunofluorescence, and microbiologic studies. Immunoassays were performed to investigate the antigenic specificities of antineutrophil cytoplasmic autoantibodies in the patients studied. All patients with lung biopsy confirmation had pauci-immune hemorrhagic alveolar capillaritis as the main morphologic substrate. In addition, renal involvement in the form of pauci-immune crescentic glomerulonephritis was a common finding. Serum samples from the 43 study patients contained antibodies that were monospecific for proteinase 3 (n = 13) or myeloperoxidase (n = 30). In our study, whereas anti-proteinase 3 antibodies were mainly detected in patients with alveolar capillaritis and a well-established diagnosis of Wegener's granulomatosis, antimyeloperoxidase antibodies were principally found in those patients who had alveolar capillaritis and polyarteritis nodosa not only as a primary finding but also accompanying other diseases. However, a significant number of patients with alveolar capillaritis and antimyeloperoxidase antibodies showed no evidence of polyarteritis nodosa (idiopathic pulmonary-renal syndrome and isolated forms of pulmonary hemorrhage). We conclude that in patients presenting with pulmonary hemorrhage as a prominent event of disease, antineutrophil cytoplasmic autoantibodies are a new clue strongly supportive of a pulmonary capillary vasculitis, irrespective of the primary underlying disease. Moreover, the antigenic subtype of antineutrophil cytoplasmic autoantibodies helps in recognizing the type of vasculitic disorder involved.

Antibodies↗
PubMed1993

[Systemic lupus erythematosus: a clinical and immunological study of 300 patients].

BACKGROUND: The aims of the present study were to analyze the clinical and immunologic characteristics of a wide group of patients with systemic lupus erythematosus (SLE) and define homogeneous subgroups with their own characteristics. METHODS: A prospective study of 300 patients diagnosed of SLE were studied. These patients were subdivided according to sex, age at the onset of the disease and immunologic profile. The statistical study was carried out by the chi (2), Fisher, Student's t and Mann-Whitney U tests. RESULTS: The series was made up of 266 (89%) females and 34 (11%) males. The mean age at onset of the disease was 31.8 +/- 14.6 years. In 48 (16%) patients the first manifestations appeared after the age of 50. Males were shown to present a lower prevalence of arthritis (59% vs 82% in woman, p < 0.005) and malar rash (29% vs 50%, p < 0.05), but had more cutaneous discoid lesions (18% vs 3% p < 0.001). In patients in whom the disease appeared after the age of 50 a lower prevalence of arthritis was presented (67% vs 82% in patients of less than 50 years of age, p < 0.005), malar rash (23% vs 53%, p < 0.001) and nephropathy (21% vs 41%, p < 0.05), but had greater myositis (17% vs 6%, p < 0.01). The absence of antinuclear antibodies (ANA) and the presence of anti-ds DNA and anti-ENA antibodies were associated with differences in the prevalence of different clinical manifestations. CONCLUSIONS: Sex, age and immunologic pattern in systemic lupus erythematosus permit the definition of homogeneous subgroups with their own characteristics: a) males present a lower prevalence of arthritis and malar rash, but a greater prevalence of cutaneous discoid lesions; b) patients over the age of 50 develop arthritis, malar rash and nephropathy with a lower prevalence but have a greater prevalence of myositis; c) patients without antinuclear antibodies and those with anti-ds DNA and anti-ENA antibodies present differences in the prevalences of different clinical manifestations.

Adolescent↗