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A Collado

Publications and source records attributed to A Collado.

At least 37 records · Page 2Linked to original sources
PubMed1999

Proteus IgG antibodies and C-reactive protein in English, Norwegian and Spanish patients with rheumatoid arthritis.

The distribution of Proteus antibody levels was compared in English, Norwegian and Spanish patients with rheumatoid arthritis (RA). Using an indirect immunofluorescence method, the IgG antibody titre against Proteus mirabilis was measured in the sera of 27 English, 53 Norwegian and 34 Spanish patients with RA and divided into active and inactive disease groups according to the serum C-reactive protein (CRP) level (> or = 10 mg/l). Serum samples were also collected from 25 English, 30 Norwegian and 14 Spanish healthy individuals who served as controls. The levels of Proteus IgG antibodies were significantly higher in the sera of active RA patients (p<0.001) when compared with the corresponding healthy controls, whether these groups belonged to the English, Norwegian or Spanish populations. Furthermore, active RA patients from each country showed significantly higher levels of Proteus antibodies when compared with inactive English (p<0.01), Norwegian (p<0.001) or Spanish (p<0.001) RA patients. Finally, a significant correlation was observed between Proteus IgG antibody levels and the CRP concentrations in RA patients whether each population was tested individually or all together (p<0.001). The increased levels of Proteus antibodies in RA patients from three different European countries support the concept of a possible aetiopathogenetic role for Proteus microorganisms in the development of RA.

Adult↗
PubMed1999

Ultrasound-guided needle aspiration in prostatic abscess.

OBJECTIVES: To review the clinical presentation of prostatic abscess and to assess the usefulness of ultrasound-guided needle aspiration as a treatment option for this condition. METHODS: Between October 1984 and November 1997, prostatic abscess was diagnosed in 31 patients. The average age was 60 years (range 29 to 79). Prostate ultrasound was performed using either a hypogastric or transrectal approach. Initial therapy included ultrasound-guided needle aspiration in 24 (77.4%), transurethral resection of prostate (TURP) in 5 (16.1%), or conservative management with antibiotic therapy. During follow-up, ultrasound examinations and urine cultures were performed on an outpatient basis. RESULTS: Past medical history most often included previous urinary infection (15 patients, 48%) and bladder outlet obstruction (13 patients, 42%). Sixty-one percent of patients presented with irritative voiding symptoms at the time of diagnosis. Ultrasound-guided needle aspiration resolved 83.3% of cases; 2 patients needed a second procedure. Three patients required TURP for drainage and 2 to remove an obstruction after abscess resolution. CONCLUSIONS: A high degree of suspicion is needed to diagnose prostatic abscess clinically. Transrectal ultrasound is necessary for the differential diagnosis. Transrectal ultrasound-guided needle aspiration is a technically simple and effective therapeutic procedure with no morbidity and, in case of failure, may be repeated or a drainage TURP may be undertaken.

Abscess↗
PubMed1999

Differential effect of protein-bound polysaccharide (PSK) on survival of experimental murine tumors.

The effect of protein-bound polysaccharide (PSK) on the survival of BALB/c and C57BL/6 mice after intravenous injections of syngeneic murine sarcomas (GR9.B9 and Meth-A), LSTRA lymphoma and B16 melanoma cells was studied. Pretreatment of mice with PSK significantly increased survival after the injection of either type of sarcoma cells, although the effect was attenuated when high numbers of cells were injected. Survival was not modified significantly in LSTRA lymphoma or B16 melanoma. Mice pretreated with anti-asialo GMI serum showed significantly decreased survival from all tumors in comparison with untreated mice injected with tumors, regardless of cell dose used. We observed an inverse correlation between H-2 antigen expression and in vitro NK sensitivity of tumor cells from all lines except B16 melanoma cells. These results clearly suggest that pretreatment of mice with PSK prolongs survival and inhibits metastasis formation in mice injected with sarcoma cells, being this effect highly selective, since survival was not improved in mice injected with LSTRA lymphoma or B16 melanoma.

Animals↗
PubMed1998

High frequency of altered HLA class I phenotypes in invasive colorectal carcinomas.

We analyzed the expression of HLA class I antigens in 78 tumor tissue samples obtained from patients diagnosed as having colorectal carcinomas. A broad panel of mAbs defining HLA monomorphic, locus-specific and allele-specific determinants was used. In addition, an antibody defining HLA-C locus-specific determinant (L31) was also tested. Previous reports on these tumors indicated HLA class I losses of 30 to 40%. At least 73% of the patients in the present study had a detectable HLA class I alteration. These altered HLA phenotypes were classified as total HLA loss (18%) (phenotype I); HLA-A locus-specific loss (9%) (phenotype IIIa); HLA-B locus-specific loss (8%) (phenotype IIIb); HLA-A and B locus losses (2%) and HLA allelic losses (36%) (phenotype IV). We found no HLA-C locus losses. Autologous peripheral blood lymphocyte HLA class I typing was always necessary to define phenotype IV. We also studied the CD3 zeta chain in tumor tissues to correlate possible changes in the CD3 signal transduction pathway with HLA alterations. The CD3 ratio was frequently altered, but this alteration could not be correlated with tumor HLA phenotypes. The high frequency of HLA class I losses in colorectal carcinomas suggests that this finding is a widespread phenomenon and may be required to escape T-cell recognition. It remains to be determined whether HLA expression is "normal" in the rest of the 27% of our patients.

Alleles↗
PubMed1998

Balloon dilatation in the treatment of ureteral stenosis in kidney transplant recipients.

OBJECTIVE: To assess the usefulness of balloon percutaneous dilatation as a starting treatment technique of ureteral stenosis in kidney transplant recipients. PATIENTS AND METHODS: A total of 472 kidney transplants have been performed at our center between August 1981 and January 1997. The coexistence of high creatinine values and urinary tract dilatation in the postoperative period, after discarding concomitant causes, was managed with a percutaneous nephrostomy. Once renal function had recovered, antegrade pyelography was performed to confirm ureteral stenosis and to determine its location. The dilatations are performed by means of 5-french balloon-fitted angioplasty catheters. RESULTS: Thirty patients were diagnosed with ureteral stenosis during follow-up, i.e. an incidence of 6.3%. Transluminal balloon dilatation was made as a first therapeutic option in 18 cases. No immediate complications were observed following dilatation. Disappearance of the stenosis as well as maintenance of the improvement in creatinine levels were verified in 39% of cases (7 patients). CONCLUSIONS: Ureteral stenosis in kidney transplant recipients should be included as part of the differential diagnosis when there is a deterioration in renal function. Balloon dilatation is the technique chosen as initial treatment of juxtavesical ureteral stenosis because of its good reproducibility and its low morbidity.

Adult↗
PubMed1997

Altered MHC class I antigens in tumors.

MHC class I antigens are lost or downregulated in invasive tumors compared with autologous normal tissues. This is observed in most of the newly induced experimental tumors analyzed if they are cloned before passaging in vivo. Similarly, this is observed in 40%-90% of human tumors using the available panel of anti-HLA class I monoclonal antibodies. In both systems the tumor populations are heterogeneous for H-2/HLA expression and composed of clones that express different amounts of MHC class I antigens. This heterogeneity may have a profound influence on tumor behavior, considering the role that MHC antigens play in T and natural killer cell-mediated responses. It is possible that the tumor escape mechanisms from T and natural killer cells select variants that express a particular MHC class I altered phenotype. We review the MHC changes detected in different experimental as well as human tumors and demonstrate the relevance of these altered H-2/HLA tumor phenotypes for implementing immunotherapeutic strategies based on T or natural killer cell-mediated responses.

Animals↗
PubMed1997

Comparative cytokine gene expression in synovial tissue of early rheumatoid arthritis and seronegative spondyloarthropathies.

Interleukin 1-beta (IL-1 beta), IL-2, IL-4, IL-5, IL-6, IL-8, tumour necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta) and granulocyte-macrophage colony-stimulating factor (GM-CSF) gene expression was determined in knee synovium of 16 patients with rheumatoid arthritis (RA) and 16 patients with seronegative spondyloarthropathies (SSP), by using polymerase chain reaction (PCR) amplification. The pattern of cytokines observed in RA synovium is of the macrophage-fibroblast type, with the highest expression of IL-1 beta and TGF-beta. GM-CSF and IL-2 bands were visualized in a minority of patients. Neither IL-4 nor IL-5 could be detected. No significant differences were observed in the cytokine profile between patients with early (< 12 months) and more advanced disease. No differences were observed according to gender, age, rheumatoid factor status and the duration of knee synovitis. The pattern of cytokines in the synovium of SSP patients is similar to that observed in RA patients and does not change in relation to disease duration. IL-2 was the only T-cell cytokine observed. These data provide evidence that the macrophage-fibroblast cells have an important role in early and more advanced rheumatoid synovitis, and show that this is also true for SSP peripheral synovitis.

Adult↗
PubMed1997

Secondary amyloidosis in ankylosing spondylitis. A systematic survey of 137 patients using abdominal fat aspiration.

OBJECTIVE: To assess the frequency and clinical significance of amyloid deposits in abdominal fat in patients with ankylosing spondylitis (AS). METHODS: Abdominal subcutaneous fat aspiration (ASFA) by fine needle was performed in 137 unselected patients with AS of more than 5 years of disease evolution. A followup study was done of patients with amyloidosis in the abdominal fat (ASFA positive test) to evaluate the development of clinical amyloidosis. RESULTS: In 10 (9M/1F) patients with AS, the ASFA revealed amyloid deposits (prevalence of 7%). Patients with AS and an ASFA+ test were older and had more active and severe disease than those without AS. Only 2 ASFA positive test patients had clinical amyloidosis at the time of the test. After a followup period of 2-10 yrs (mean 5.4 +/- 3.2 yrs), 3 more patients developed symptomatology due to amyloidosis. All 5 patients with clinical amyloidosis showed nephropathy, and proteinuria was found in each. The remaining patients did not develop clinical amyloidosis during followup. CONCLUSION: Amyloid deposits in abdominal fat are not a rare finding in AS. A significant proportion of these patients do not develop clinical amyloidosis after a followup of several years. Thus, an ASFA + test in patients with AS is not always associated with a poor prognosis at least in the short term, although longer followup is required.

Adipose Tissue↗
PubMed1997

Protein bound polysaccharide PSK abrogates more efficiently experimental metastases derived from H-2 negative than from H-2 positive fibrosarcoma tumor clones.

We studied the effect of protein-bound polysaccharide PSK on metastatic colonization of BALB/c mice after intravenous injections of different syngeneic murine H-2 positive and H-2 negative tumor clones. The tumor lines used were different clones from chemically induced fibrosarcomas (GR9.B9, an H-2 negative clone from GR9 tumor, and B7.1.B4, an H-2 positive clone from B7.1 tumor). These clones were selected because of their different sensitivity to NK cytotoxicity, which was related to MHC class I expression. Pretreatment of mice with PSK inhibited metastatic colonization derived from B9 H-2 negative tumor cells. In contrast, lung colonization of PSK treated mice injected with B7.1.B4 H-2 positive tumor cells was higher, and differences in the number of colonies between untreated and PSK treated mice were small. In several experiments the effect of PSK was attenuated to a greater degree when high numbers of cells were injected. Abrogation of NK cells with anti-asialo GM1 serum significantly increased (in all tumors and at different cell doses) the number of metastatic colonies in comparison with untreated mice injected with tumors, regardless of the cell dose used. These results clearly suggest that NK cell activation in vivo by the protein bound polysaccharide PSK abrogates metastasis formation in mice. Abrogation was dependent on the H-2 phenotype even when pretreatment consisted of a single dose of PSK. This effect, related to the NK sensitivity of the tumor target, can be used to predict the effect of PSK in vivo.

Animals↗
PubMed1996

Molecular mimicry: the geographical distribution of immune responses to Klebsiella in ankylosing spondylitis and its relevance to therapy.

The discovery that HLA-B27 is linked to ankylosing spondylitis (AS) and HLA-DR1/DR4 to rheumatoid arthritis (RA) has provided new approaches to the study of the possible causation of these diseases. Several theories have been proposed to explain these associations but only one, namely "molecular mimicry", has provided a specific aetiological agent for each of these diseases. Molecular mimicry between HLA-B27 and two molecules in Klebsiella microbes: nitrogenase and pullulanase D has been reported whilst in Proteus microbes, the haemolysin molecule shows sterochemical similarity to HLA-DR1/DR4. Elevated immune responses to Klebsiella microbes have been demonstrated in AS patients from 10 different countries and this wide geographical distribution suggests that the same aetiological agent is probably acting in producing this condition. Furthermore RA patients show similar immune responses to Proteus microbes. Whether AS or RA are caused by these bacteria can only be resolved by tissue typing all rheumatological patients early, in the course of their disease and then assessing their response to antibiotic chemotherapy in longitudinal studies involving double-blind crossover trials. It is possible that in the future, the course of AS or even RA could be modified by adequate antibiotic chemotherapy or even diets which affect the substrates on which these bacteria grow.

Antibodies, Bacterial↗
PubMed1996

Scintigraphic evaluation of the severity of inflammation of the joints with 99TCm-HIG in rheumatoid arthritis.

A prospective study was carried out to determine the usefulness of 99TCm-human immunoglobulin G (HIG) scintigraphy in the assessment of the severity of joint inflammation. Twenty-four patients with rheumatoid arthritis were studied. The presence or absence of pain and/or swelling was evaluated in 34 joints and a clinical index taking into account the surface area of each joint was calculated. We measured the following biological markers of inflammation activity: erythrocyte sedimentation rate, C-reactive protein, haemoglobin, platelet count, serum levels of IL-6, TNF-alpha and soluble receptors of IL-2. Scintigraphic was performed 4 h after the injection of 740 MBq 99Tcm-HIG. The scans were evaluated by visual and quantitative analysis and the scores in each joint were weighted for joint size. Pathological uptake of the radiopharmaceutical was noted in 46% (24/52) of joints evaluated as painful, 89% (146/164) of swollen joints and 94% (78/83) of both painful and swollen joints. Both the visual and the quantitative scintigraphic indices correlated significantly with the clinical index, the number of painful joints, the number of swollen joints and several biological markers of inflammation. A very high correlation was also found between the visual and the quantitative scintigraphic indices (r = 0.91, P < 0.0001). In conclusion, 99Tcm-HIG scintigraphy is an objective test to detect synovitis and to assess the severity of inflammation. A careful visual analysis of scans is good enough for routine evaluations and computer quantitative analysis should be used when more accurate intra-individual variation is required.

Adult↗
PubMed1996

Reduced serum creatine kinase activity in inflammatory rheumatic diseases.

OBJECTIVE: To determine if serum CK activity is reduced in inflammatory rheumatic diseases and to evaluate whether this phenomenon is linked to disease activity or steroid therapy. METHODS: Serum CK activity was measured in patients with systemic lupus erythematosus (SLE, n = 52), rheumatoid arthritis (RA, n = 80), ankylosing spondylitis (AS, n = 82), spondyloarthropathies other than AS (SpA, n = 22), and a miscellaneous group (MI, n = 27), and in 103 control patients with noninflammatory arthropathies (NIA). Laboratory variables of inflammatory activity such as ESR, CRP, platelet count, and hemoglobin (and anti-DNA antibodies and complement levels in SLE) were measured at the same time. Daily dose of steroids was also evaluated. RESULTS: Serum CK activity was significantly reduced in SLE (mean +/- SD: 49 +/- 41 IU/l), RA (68 +/- 41 IU/l), SpA (88 +/- 53 IU/l), and MI (75 +/- 32 IU/l) compared to controls (111 +/- 38 IU/l) (p = 0.002 for SpA and p < 0.001 for the other groups). No differences in CK values were observed between AS and controls, although AS patients with peripheral arthritis had lower serum CK activity than those without (80 +/- 32 vs 121 +/- 62 IU/l, respectively, p < 0.05. ESR, CRP, and platelets correlated inversely with CK values in RA, AS, and MI. In the SpA group only ESR correlated inversely with CK. In SLE, a positive correlation was found between CK values and CH50 and a negative one with anti-DNA levels. Patients taking steroids had significantly lower CK activity than those without corticotherapy. However, multivariate analysis showed that only inflammatory activity and no steroids had an effect in reducing CK activity. CONCLUSION: Serum CK activity is significantly reduced in several inflammatory rheumatic diseases. Inflammatory activity seems to play the major role in this phenomenon.

Adult↗
PubMed1995

[Arthropathy associated with infection by parvovirus B19. Description of 4 cases].

Four cases of human parvovirus infection in which the main clinical manifestation was a polyarthritis are described. Four females with ages ranging from 30 to 32 years presented with acute symmetrical polyarthralgias involving hands and knees. In addition, evidence of synovitis in the ankles and tenosynovitis of the fingers was found in two and three cases respectively. Half of the patients noticed an erythematous rash in the preceding days. Laboratory studies were normal in all cases. Antinuclear antibodies and rheumatoid factor were not detected in any case. All patients had significant levels of IgG and IgM antibodies to parvovirus B19 at the time of presentation and a rise in IgG and a fall in IgM levels were seen at two months. All cases cleared up within two weeks without treatment.

Adult↗
PubMed1995

Different patterns of HLA-DR antigen expression in normal epithelium, hyperplastic and neoplastic malignant lesions of the breast.

Fifteen samples of non-tumoural breast tissue, 24 cases of benign lesions, four biopsies of inflammatory carcinomas and 94 tumour samples of primitive mammary carcinomas were analysed for HLA class II expression. We found, first, that HLA class II antigens were detectable in all cases of non-neoplastic breast tissue. Secondly, HLA class II antigen expression was notably increased in benign neoplasms and hyperplastic lesions. In contrast, only 32 out of 94 carcinomas showed expression of HLA-DR antigens, 17 tumours had HLA-DP antigens and 11 carcinomas were positive for the presence of DQ molecules. The expression of class II antigen was associated with the degree of histological differentiation (P < 0.05) but was independent of stromal leucocytic infiltration. Thirdly, HLA-DR was very strongly expressed in intravascular tumoural thrombi, especially in the 'inflammatory carcinomas'. The immunophenotype of inflammatory infiltrate was analysed in benign and malignant lesions. In malignant lesions the mean number of inflammatory cells was significantly higher than in benign lesions. Interestingly, we found no differences in the amount and composition of inflammatory infiltrate between HLA-DR positive and negative tumours.

Adenocarcinoma↗
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↗