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C Juárez

Publications and source records attributed to C Juárez.

At least 19 recordsLinked to original sources
PubMed2002

Monoclonal antibodies to amoxicillin express different idiotypes determined by anti-idiotype antibodies production.

Penicillins are beta-lactam antibiotics able to generate several antigenic determinants that are recognized by the immune system. To study the differences in the antigen binding site of two monoclonal antibodies (Mab) specific to amoxicillin, polyclonal rabbit anti-idiotypic antibodies were produced. One Mab, AO3.2 (IgG2a), specific to a structure formed by the acyl-side chain structure and a part of the nuclear region of amoxicillin. The second one, AO6.2 (IgE), is specific to the side chain of amoxicillin, although it also recognizes the side chain of other penicillins (penicillin G and ampicillin). These antibodies were used to immunize rabbits in order to produce polyclonal anti-idiotypic antibodies, which were purified in several steps by affinity chromatography. The specificity and cross-reactivity studies were made by ELISA and ELISA inhibition. The results suggest that the anti-Id antibodies produced are the internal image of the antigen, since the binding to their specific idiotype is blocked mainly by the original hapten (amoxicillin): in 98% of the cases with anti-id-1 (induced against AO3.2) and in 59% with anti-id-2 (induced against AO6.2). The absence of cross-reactivity of each anti-idiotypic antibody with the different Mabs specific to amoxicillin shows that the idiotypes induced by the same hapten have differences that are reflected by the nonrecognition of these anti-idiotypes. We conclude that such a small molecule as amoxicillin can present several antigenic determinants that induce a panel of antibody specificities especially directed against the side chain.

Amoxicillin↗
PubMed2001

Clinical aspects and prognostic factors in elderly patients hospitalised for community-acquired pneumonia.

The aims of this study were to determine the clinical and epidemiological characteristics of community-acquired pneumonia (CAP) in the elderly, to identify prognostic factors, and to establish a predictive model for mortality of CAP. Elderly patients with CAP admitted to "Carlos Haya" Hospital in Malaga, Spain, over a 36-month period were included. Multivariate analysis was used to identify prognostic factors from variables present on admission, from which a discrimination rule was constructed to predict mortality. A total of 343 patients were included, with the annual incidence ranging from 16.3 to 28.1 per 1,000 admissions. Most (82.5%) had some kind of accompanying or underlying disease. Clinical presentation was atypical in 87 (25.4%). Microbiological diagnosis was made in 24.5%. There were 49 (14.3%) deaths. The prognostic factors in multivariate analysis on admission were bilateral radiographic infiltrate, a blood urea nitrogen level of more than 7 mmol/l, absence of fever, a respiratory rate of 30/min or more, confusion, and shock. The discriminating rule to predict mortality comprising three or more of these factors was 91.2% specific, with a negative predictive value of 93.4% and an overall accuracy of 86.9%. CAP in the elderly is associated with a high degree of mortality. The discriminating rule incorporating the prognostic factors identified is a powerful predictor of mortality.

Aged↗
PubMed2001

In vitro T-cell responses to beta-lactam drugs in immediate and nonimmediate allergic reactions.

BACKGROUND: beta-Lactam drugs may induce both cellular and humoral allergic reactions, and there is evidence that T cells play an important role in the pathogenesis of these reactions. The aim of this work was to assess the sensitivity and specificity of the lymphocyte transformation test (LTT) as an in vitro diagnostic tool, in patients with either an immediate or a nonimmediate reaction to penicillin G and/or amoxicillin. METHODS: Fifty patients with a well-documented history of allergic reactions to beta-lactams (31 immediate and 19 nonimmediate) were studied by means of skin tests (prick and intradermal), radioallergosorbent test (RAST), and, when necessary, controlled administration of the drug. Twenty-eight healthy subjects with good tolerance to penicillins served as controls. LTT was performed in all subjects. RESULTS: Skin tests were positive in 77.4% of the patients with immediate reactions and in 36.8% of those with nonimmediate reactions. The overall sensitivity of LTT in the allergic patients was 62%, but, when analyzed separately, sensitivity was 64.5% for the immediate group and 57.9% for the nonimmediate group. The LTT specificity was 92.8%. CONCLUSION: The LTT should be considered a useful in vitro diagnostic tool to identify subjects allergic to penicillins, especially patients with nonimmediate reactions where the LTT has a better diagnostic value than skin tests. Interestingly, positive T-cell proliferative responses can be observed 10 or more years after the occurrence of the reaction without further exposure to the drug.

Adult↗
PubMed2000

Anticonvulsant-induced toxic epidermal necrolysis: monitoring the immunologic response.

BACKGROUND: Toxic epidermal necrolysis is a severe reaction with skin involvement induced by different drugs and other agents. The mechanisms implicated in the induction of the reaction are poorly understood. OBJECTIVE: Our purpose was to study the involvement of T lymphocytes and other immunocompetent cells in the peripheral blood, blister fluid, and affected skin of 3 patients who had a severe reaction after receiving anticonvulsant medication. METHODS: Quantification of T lymphocytes expressing the skin-homing receptor (cutaneous lymphocyte-associated antigen ¿CLA) in peripheral blood, skin, and skin blister fluid and assessment of other adhesion molecules, activation markers, and inflammatory interleukins by flow cytometry, immunohistochemistry, and reverse transcription-PCR. RESULTS: An increase in CD3(+)CLA(+) cells paralleling the severity of the disease was observed in both peripheral blood and skin, tending to normalize as soon as patient's conditions improved. E-selectin was detected in endothelial vessels in parallel with CLA expression on lymphocytes. An overexpression of TNFalpha, IFN-gamma, and IL-2 was also observed in PBMCs. The expression of the different markers changed over the course of the disease. CONCLUSIONS: These data show an increase in activated T cells expressing the skin-homing receptor in both tissue and peripheral blood accompanying clinical symptoms, with a recruitment of macrophages and an overexpression of cytokines. All these results suggest an important role for T cells in the production of toxic epidermal necrolysis.

Adult↗
PubMed1999

Diagnostic usefulness of percutaneous liver biopsy in HIV-infected patients with fever of unknown origin.

OBJECTIVES: to determine the value of percutaneous liver biopsy (PLB) in the diagnosis of fever of unknown origin (FUO) in HIV-infected patients and establish a prediction model for its usefulness to enable diagnosis of FUO in these patients to be standardized. METHODS: a total of 58 HIV-infected patients who underwent PLB for the evaluation of FUO were studied at 'Carlos Haya' Hospital in Malaga, Spain. The patients were classified into three groups, according to the results of the PLB: (a) diagnostic PLB (when a definitive diagnosis was obtained); (b) helpful PLB (the tissue sample showed suggestive, but not definitive, findings); and (c) normal or non-specific PLB (no contribution to diagnosis, the findings being normal or irrelevant). Multivariate analysis was made to establish a prediction model for the diagnostic usefulness of PLB, calculating the positive (PPV) and negative (NPV) predictive values. RESULTS: PLB was carried out in 58 HIV-infected patients during diagnosis of FUO. Risk factors for HIV infection included intravenous drug use (72.4%), homosexual or bisexual activities (12.1%), and heterosexual transmission (15.5%). Fifty-two out of 58 patients (89.6%) had previous AIDS-defining illnesses. The mean CD4 lymphocyte count +/-SD was 56.4+/-80.9/mm3. The mean duration of fever was 43 days. Diagnosis could be established in 51 (87.9%) patients, with tuberculosis (50%) and leishmaniasis (20.7%) being the most common. The PLB was diagnostic in 25 cases (43.1%), helpful in 13 (22.4%), and normal or non-specific in the remaining 20 (34.5%). Biopsy-associated complications occurred in two cases. The presence of hepatomegaly or splenomegaly were the most useful factors in predicting the usefulness of the PLB, with a PPV of 86.1% and NPV of 68.2%. In patients with tuberculosis, an increased alkaline phosphatase and hepatomegaly had a PPV of 86.4% and a NPV of 71.4%. CONCLUSIONS: PLB is a useful technique for the diagnosis of FUO in HIV-infected persons. Early PLB should be considered in those patients with hepatosplenomegaly and increased alkaline phosphatase levels.

Adult↗
PubMed1998

[Incidence and current clinical spectrum of tuberculosis in a metropolitan area in the south of Spain].

BACKGROUND: To study the incidence and clinical spectrum of tuberculosis in the metropolitan area of Málaga (Spain). METHODS: Prospective study which includes all patients who had a diagnosis of tuberculosis within the referral area of "Carlos Haya" Málaga Regional Hospital from March 1, 1993 to February 28, 1994. RESULTS: During the study period, there were 138 cases of tuberculosis, with an incidence of 43.7 cases/10(5) inhabitants. Ninety one cases (66%) were male, and the mean age (SD) was 33.2 (18.3), with 88% being less than 55 years old. Thirty six patients (26.1%) were HIV-infected. Extrapulmonary tuberculosis made up 27.5% of the cases, and was more frequent in HIV-infected patients (p < 0.01; odds ratio: 2.9; 95% CI: 1.2-7.1). The mean (SD) time to diagnosis was 54.3 (76) days. The diagnosis was microbiologically confirmed in 106 cases (76.8%), histologically in 14 cases (10.1%), and the remaining 18 cases (13.1%) were clinically diagnosed. The global rate of resistance was 10.8%. The rate of primary resistance was 4.6%, and the rate of multidrug-resistant tuberculosis was 3.1%. Eighty nine patients (77.4%) were cured, six patients (5.2%) stopped the treatment, 3 (2.6%) had relapses and 1 (0.9%) was considered a therapeutic failure; 16.7% of patients were lost for follow-up. Sixteen patients died and in nine of them (6.5%) the death was attributed to tuberculosis. CONCLUSIONS: The incidence of tuberculosis in Málaga urban area is high. It mainly affects young males of unfavored socio-economic classes. HIV-infected patients account for a high percentage of the cases. The high number of productive cases and the long time to diagnosis evidence the shortcomings of our sanitary system. These facts, together with the high rate of non-compliance, of treatment may explain the seriousness of the current situation in our country.

Adolescent↗
PubMed1997

Signal transducer and activator of transcription 1 in human muscle: implications in inflammatory myopathies.

Polymyositis (PM) and dermatomyositis (DM) are two major and distinct inflammatory myopathies. Cytokines, implicated in the immune process, have been recognized in the muscle tissue from PM and DM patients, but their functional in situ role has not been identified. We analyzed the expression of the signal transducer and activator of transcription 1 (STAT1), a molecule whose up-regulation indicates the interaction of cytokines, or growth factors, with their target receptors in muscle fibers and inflammatory infiltrates in PM and DM. An immunohistochemical analysis was performed using monoclonal antibodies to STAT1 in 57 muscle biopsies from 10 patients with DM, 10 with PM, and 37 controls. The profile of STAT1 up-regulation was also investigated in cultured muscle stimulated by interferon-gamma, epidermal growth factor, platelet-derived growth factor, and interleukin-2, using semiquantitative polymerase chain reaction and Western blot. High STAT1 expression was observed in many perifascicular atrophic muscle fibers from DM patients in 10/10 biopsies. In contrast, only a few muscle fibers undergoing necrosis were STAT1 positive in 2/10 patients with PM and in 2/37 controls. STAT1 reactivity was noted in most cells of the infiltrates in DM, PM, and controls. In vitro, STAT1 was stimulated by interferon-gamma but not by the other molecules studied. These results suggest that in DM, but not in PM, there is distinctive functional local cytokine activity able to increase STAT1 expression in muscle fibers. As interferon-gamma specifically activates STAT1 in vitro, this cytokine in conjunction with ischemia is probably involved in perifascicular muscle fiber pathology in DM.

Blotting, Western↗
PubMed1997

[Compliance, efficacy and tolerability of the therapeutic regimen recommended by National Consensus on Tuberculosis].

BACKGROUND: To study the degree of adhesion, efficacy, and tolerance of therapeutic guidelines advocated by the National Consensus on tuberculosis. METHODS: A prospective study of a cohort of 84 patients receiving a diagnosis of tuberculosis in a Basic General Health Area between 1-3-1993 and 28-2-1994 treated with the regimen recommended by the National Council. The patients were evaluated clinically and microbiologically during the treatment and during twelve months follow-up. RESULTS: Fifty-two patients (61.9%) were male and 32 (38.1%) female, aged 29.9 +/- 19.7 years (r = 1-84 years). Seventy-four (88.1%) were index cases and 10 (11.4%) household contacts. Eight patients (9.5%) were also infected with HIV, 71 (84.5%) presented pulmonary tuberculosis and 13 (15.5%) extrapulmonary forms. Therapeutic compliance was correct in 80 cases (95.2%) and incorrect in 4 (4.8%). It was well-tolerated in 73 patients (91.2%), there was slight toxicity in five (6.3%) and severe in two (2.5%). Seventy-four patients (88.1%) were cured, there was one therapeutic failure (1.2%) and five relapses (6%). Overall mortality was 4.8% and attributable mortality 1.2%. CONCLUSION: Our results seem to confirm a high degree of adhesion, good tolerance and acceptable therapeutic efficacy of the scheme proposed by the National Council.

Adolescent↗
PubMed1996

Complications associated with Brucella melitensis infection: a study of 530 cases.

We carried out a prospective study of 530 patients older than 14 years of age with brucellosis. We describe the incidence and clinical features of the focal forms of the disease, analyzing some of the possible factors associated with their appearance. One hundred sixty-nine patients (31.9%) had a focal form or complication. Osteoarticular complications were the most frequent, totaling 113 cases (66%), followed by genitourinary with 18 cases (5.1% of males), hepatic (2.5%), neurologic (1.7%), and heart (1.5%). Nine patients (1.7%) had more than 1 complication. In a multivariate analysis, diagnostic delay greater than 30 days (OR 2.0), ESR > 40 mm/hr (OR 1.9), and levels of alpha-2 globulin > 7.5 g/L (OR 6.8) were statistically significant independent variables associated with the presence of focal forms. Twenty-five patients with complications (14.8%) required surgical treatment. The relapse rate was 3.6% for those patients without complications and 4.1% for patients with focal forms (p > 0.05). However, when therapeutic failure, relapses, and mortality were considered together, the risk of an unfavorable evolution was significantly greater in patients with focal forms (10.6% versus 3.6% in patients without complications; OR 1.9, 95% CI 1.4-7.1, p < 0.005). Given the worse prognosis, knowledge and early diagnosis of the focal forms of B. melitensis infection is especially important.

Adolescent↗
PubMed1996

Monounsaturated fatty acid (avocado) rich diet for mild hypercholesterolemia.

To assess the effect of a high monounsaturated fatty acids (MFA) diet on serum lipids, 30 healthy adult normolipidemic volunteers and 37 adult patients with mild hypercholesterolemia (5.4-9.3 mmol/l), 15 of them also with hypertriglyceridemia (2.3-4.8 mmol/l), were studied. Fifteen healthy and 30 hypercholesterolemic subjects (15 of them with associated type 2 diabetes mellitus) received an avocado enriched diet (2000 Kcal, lipids 53% MFA 49 g saturated/unsaturated ratio 0.54), and seven non-diabetic hypercholesterolemic individuals received an isocaloric control diet (MFA 34 g, saturated/unsaturated ratio 0.7). Serum total cholesterol, LDL-cholesterol, HDL-cholesterol and triglyceride concentrations were measured before and after a 7-day diet period. In healthy individuals a 16% decrease of serum total cholesterol level followed the high MFA diet, while it rose after the control diet (p < 0.001 between diets). In hypercholesterolemic subjects a significant (p < 0.01) decrease of serum total cholesterol (17%), LDL-cholesterol (22%) and triglycerides (22%), and increase of HDL-cholesterol (11%) levels occurred with the avocado diet, while no significant changes were noticed with the control diet. High lipid, high MFA-avocado enriched diet can improve lipid profile in healthy and especially in mild hypercholesterolemic patients, even if hypertriglyceridemia (combined hyperlipidemia) is present.

Adolescent↗
PubMed1994

[Chlamydia trachomatis and tubal obstruction sterility].

In order to determine the importance of Chlamydia trachomatis in infertility due to tubal occlusion, the prevalence of C. trachomatis antibody was studied in two populations of Argentine women, pregnant and infertile with tubal occlusion. IgG and IgM against C. trachomatis were determined by indirect immunofluorescence in McCoy cells infected with strain L2Bu434 of C. trachomatis. In infertile women, specific anti-C. trachomatis IgM was detected in 5 out of 32 (15.6%) and IgG in 20 out of 32 (75%). In pregnant women, specific IgM was detected in 4.8% (4/83) and IgG in 20.5% (17/83). The frequency of IgG detection was significantly higher in infertile than in pregnant women (p < 0.000). Thirteen out of 20 (65%) women who underwent laparoscopic examination had evidence of chronic inflammatory disease described as yellowish viscous cysts resembling "frog eggs" in Douglas, utero and/or perihepatitis. Twelve out of fourteen (86%) infertile women with positive serology for C. trachomatis presented one or more of these laparoscopic findings. C. trachomatis antigen was detected in 2 out of 10 tubal biopsies by direct immunofluorescence with monoclonal antibodies although isolation in McCoy cells was negative. Our results show the importance of C. trachomatis in infertility due to tubal occlusion and the need of C. trachomatis diagnosis in routine gynecologic analysis to prevent infertility and neonatal infection.

Adolescent↗
PubMed1994

[Neurophthalmological alterations in multiple sclerosis].

With the aim of defining the neuro-ophthalmological alterations in multiple sclerosis, both with respect to visual and oculomotor aspects, we have studied a sample of 100 clinically definite multiple sclerosis patients, all in the remittent phase of the disease. We compared them with a sample of 100 unrelated healthy controls, matched for age and sex. Visuomotor alterations were found in 99%, purely visual alterations in 38%, purely oculomotor alterations in 3%, and mixed alterations in 58% of the MS patients. Comparisons with controls showed significant statistical differences in all the tests used in the study. The neuro-ophthalmological examination in multiple sclerosis permits us to detect subclinical lesions and arrive at a better comprehension of central nervous system involvement in this disease, thereby contributing collaborating to better patient care.

Age of Onset↗
PubMed1993

Preexisting human anti-murine antibodies and the effect of immune complexes on the outcome of immunoscintigraphy.

Radiolabeled monoclonal antibodies (MoAb) are useful in radionuclide imaging. Human anti-murine antibodies (HAMA), however, could produce immunologic effects or alter the outcome of immunoscintigraphy. Three patients are reported who had been exposed previously to radiolabeled MoAbs and in whom subsequent immunoscintigraphy was performed. All patients showed abnormal biodistribution of the antibody and increased hepatic uptake. Human anti-murine antibody was demonstrated in all patients. These results indicate that immune complexes are formed after HAMA-MoAb reaction and are then phagocytosed by cells of the reticuloendothelial system.

Aged↗
PubMed1991

[Ergotism].

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Adult↗