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F Mendoza

Publications and source records attributed to F Mendoza.

At least 19 recordsLinked to original sources
PubMed1999

Antilisterial activity of peptide AS-48 and study of changes induced in the cell envelope properties of an AS-48-adapted strain of Listeria monocytogenes.

The peptide AS-48 is highly active on all Listeria species. It has a bactericidal and bacteriolytic mode of action on Listeria monocytogenes CECT 4032, causing depletion of the membrane electrical potential and pH gradient. The producer strain Enterococcus faecalis A-48-32, releases sufficient amounts of AS-48 into the growth medium to suppress L. monocytogenes in cocultures at enterococcus-to-listeria ratios above 1 at 37 degreesC or above 10 at 15 degreesC. As the temperature decreases, the bactericidal effects of AS-48 are less pronounced, but at 2.5 microgram/ml it still can inhibit the growth of listeria at 6 degreesC. AS-48 is highly active on liquid cultures, although concentrations above 0.2 microgram/ml are required to avoid adaptation of listeria. AS-48-adapted cells can be selected at low (but still inhibitory) concentrations, and they can be inhibited completely by AS-48 at 0.5 microgram/ml. The adaptation is lost gradually upon repeated subcultivation. AS48(ad) cells are cross-resistant to nisin and show an increased resistance to muramidases. Their fatty acid composition is modified: they show a much higher proportion of branched fatty acids as well as a higher C15:0 An-to-C17:0 An ratio. Resistance to AS-48 is also maintained by protoplasts from AS48(ad) cells. Electron microscopy observations show that the cell wall of AS48(ad) cells is thicker and less dense. The structure of wild-type cells is severely modified after AS-48 treatment: the cell wall and the cytoplasmic membrane are disorganized, and the cytoplasmic content is lost. Intracytoplasmic membrane vesicles are also observed when the wild-type strain is treated with high AS-48 concentrations.

Anti-Bacterial Agents↗
PubMed1998

Antiaorta antibodies and Takayasu arteritis.

A search for antibodies reactive against a total human aorta extract and its main protein components such as elastin, fibronectin and collagen was attempted by electroimmunetransference and ELISA. Thirty five sera from clinically and angiographically proven diagnosis of Takayasu Arteritis patients were compared with 32 sera from people without abnormalities. Non specific binding was found on electroimmune transference and no difference was shown in optical density readings in ELISA, therefore, we did not demonstrate the presence of antiaorta specific antibodies in this vasculitic condition. Our findings are in agreement with several authors, the contribution of humoral immunity to pathogenesis of Takayasu Arteritis has not been proved yet.

Adult↗
PubMed1997

[Cat-scratch disease. A report of 4 cases and a review of the literature].

Four cases of cat-scratch diseases are here reported and a review of the literature is made. The disease, apart from its typical presentation form as a usually self-limited regional lymph node enlargement, can occasionally spread and involve several organs systems. Indirect immunofluorescence serological tests have been of help for its diagnosis and should be included among the diagnostic criteria for the disease. In particular cases, nuclear magnetic resonance can be useful to suggests the diagnosis.

Adolescent↗
PubMed1997

On the correct determination of reference values for serum antibodies against pigeon serum antigen using a group of healthy blood donors.

An enzymatic immunoassay was developed in order to evaluate the statistical distribution of IgG serum antibodies against pooled pigeon sera antigen in 102 healthy blood donors (HBD). A non-normal distribution was obtained as demonstrated by abnormal values of skewness (2.02) and kurtosis (6.50). A cut-off point (0.120) was determined from the mean plus 2 standard deviations of the optical density values obtained in the HBD group. This value was able to segregate 94% of subjects. However, when calculation of the mean less 2 SD was performed to delimit 95% of the samples, an aberrant negative value was obtained. In contrast, when the nonparametric method of percentile calculation was applied, an optical density value of 0.130 discriminated 97.5% of samples. In addition, the interval between p97.5 and p2.5 delimited 95% of samples. We conclude that when reference values and cut-off point are determined from an enzymatic immunoassay, careful analysis of the statistical distribution of reference values is necessary in order to avoid the inappropriate application of parametric procedures as demonstrated in this study for antibodies against pigeon serum antigens.

Adult↗
PubMed1997

Cefodizime once daily in the treatment of lower respiratory tract infections.

Cefodizime (CAS 69739-16-8, HR 221) is a new third-generation cephalosporin with pharmacokinetic properties that make it suitable for once-daily administration in the treatment of lower respiratory tract infections (LRTI). Ninety-nine adult hospitalized patients (66 males, 33 females, median age 57.5 years) received a once-daily injection of 2 g cefodizime for LRTI. Median treatment duration was 8 days. Forty-two patients received cefodizime intravenously and 57 intramuscularly. Indications for treatment were as follows; primary lobar pneumonia (n = 36), bronchopneumonia (n = 14), secondary pneumonia (n = 3), aspiration pneumonia (n = 5), acute exacerbation of chronic bronchitis (n = 21), and of bronchiectasis (n = 9) and acute purulent bronchitis (n = 11). General condition was good in 29 patients and poor in 58; 12 patients were critically ill. The following pathogens were isolated at baseline (source: bronchial secretions, sputum or blood): S. pneumoniae (n = 47), Haemophilus spp. (n = 17), M. catarrhalis (n = 6), Streptococcus spp. (n = 9), Staphylococcus spp. (n = 5), Klebsiella spp. (n = 4), Pseudomonas spp. (n = 1), A. calcoaceticus (n = 1) and anaerobic organisms (n = 7). Fifty-nine patients were evaluable for bacteriological response and 82 for clinical response. Bacteriological outcome was satisfactory in 29/30 patients having LRTI with parenchymal involvement (97%) and in 29/29 patients without parenchymal involvement (100%). Clinical cure was achieved in 41/43 evaluable patients with parenchymal involvement (95%) and in 37/39 patients without parenchymal involvement (95%) in the per-protocol analysis and in 54/58 patients (93%) and 37/41 patients (93%), respectively, in the clinical intention-to-treat analysis. Three of the patients with an unsatisfactory clinical response died of infection during the study. Cefodizime was well tolerated. Adverse reactions--all of mild intensity--were tachycardia, lumbalgia and dizziness, each occurring in one patient. Cefodizime 2 g once daily either i.m. or i.v. was effective in the treatment of lower respiratory tract infections in hospitalized patients.

Adult↗
PubMed1996

Detection of salivary and seric IgG and IgA antipooled pigeon sera activities in patients with pigeon breeder's disease.

Pigeon breeder's disease (PBD) is an interstitial lung disease induced by exposure to pigeon antigens. Search of antipigeon antigen antibodies (APSA) in serum or bronchoalveolar lavage is generally used for auxiliary diagnostic purposes. However, APSA can be present in a number of exposed but asymptomatic individuals as well as in patients with other interstitial lung diseases who live in areas where keeping pigeons is a common domestic habit. In this study, saliva was evaluated as an alternative means to serum for APSA detection by ELISA using pooled pigeon sera as antigen. Serum and saliva samples obtained from 17 patients with PBD, 14 with idiopathic pulmonary fibrosis (IPF), 19 asymptomatic relatives (AR) exposed to pigeon antigens, and 27 clinical healthy voluntary subjects (CHVS) were tested for IgG and IgA APSA. Our results showed that both fluids obtained from PBD patients exhibited a significantly higher specific IgG antibody activity compared to the other groups. Serum optical density (O.D.) values for PBD were 1.187 +/- 0.738 vs. 0.024 +/- 0.033, 0.255 +/- 0.471, and 0.204 +/- 0.346 for CHVS, AR and IPF, respectively (P < 0.05). Salivary O.D. for PBD were 0.801 +/- 0.447 vs 0.010 +/- 0.011, 0.104 +/- 0.151, and 0.22 +/- 0.447 (P < 0.05). In contrast, serum specific IgA did not discriminate between PBD and IPF patients. In addition, although the PBD group exhibited the highest values of IgA salivary APSA, high levels were also observed in saliva specimens from CHVS, a group of normal individuals who deny pigeon exposure. These findings suggest that measurement of IgG salivary APSA can play a role in the evaluation process of patients with pigeon breeder's disease.

Adult↗
PubMed1996

Cellular immune response to fractionated avian antigens by peripheral blood mononuclear cells from patients with pigeon breeder's disease.

Pigeon breeder's disease (PBD), a form of hypersensitivity pneumonitis caused by repeated inhalation of antigens of pigeon origin, is characterized by a diffuse inflammation of the lower respiratory tract. Although a variety of immunologic and nonimmunologic mechanisms have been described in the development of the disease, the pathogenesis is still far from clear. In this study we analyzed the T-lymphocyte proliferative response to a variety of avian antigens with use of peripheral blood mononuclear cells from 11 patients who had PBD and 10 healthy volunteers. We used a new method based on avian antigen-bearing nitrocellulose particles derived from Western blots to study the T-cell proliferative response to 15 antigenic fractions obtained from pigeon serum. With this technique, complex mixtures of antigens can be fractionated by polyacrylamide gel electrophoresis, transferred to nitrocellulose membranes, and used for T-cell proliferation assays with selected antigenic determinants. A wide variety of responses were observed, and there were no reproducible patterns of reaction within either group. Nine of 10 healthy subjects responded to some soluble fractions. However, patients with PBD displayed the strongest response and responded to a significantly greater number of antigenic fractions. Fraction 2, representing a 220 kd molecular weight protein, was the only immunodominant antigen when both groups were compared; it was recognized by 73% of the patients with PBD and by only 20% of control subjects (p < 0.03). These findings show that T lymphocytes of patients with PBD recognize a wide range of bird proteins, which induce marked T-cell proliferation.

Adult↗
PubMed1994

Dopamine-induced antihypertensive effects and plasma insulin rise are blocked by metoclopramide in labetalol-treated patients.

Eleven patients with moderate to severe hypertension were studied at the Vargas Hospital of Caracas. The patients were pretreated with labetalol, 800 to 1200 mg/day, orally, over a period of 1 week, after which an intravenous infusion of dopamine, .5 to 3 micrograms/kg/minute, was given. Two intravenous dopamine infusions (30 minutes each) were performed before and after the injection of metoclopramide (30 mg, intravenous bolus). Two washout periods were also included before and after metoclopramide administration. Dopamine induced a decrease of blood pressure from 171.9 + 6.35/103.6 +/- 3.12 to 152.7 +/- 7.55/93.8 +/- 2.97 mm Hg (P < .001) without altering heart rate, and it increased plasma insulin levels from 8.29 +/- .70 microU/mL to 12.09 +/- 1.83 microU/mL (P < .01). Metoclopramide caused no changes of blood pressure or plasma insulin levels. Hypotensive responses and plasma insulin increases due to dopamine were blocked by metoclopramide, however. The authors conclude that a dopaminergic receptor may be involved in some cardiovascular responses and in modulating insulin secretion in humans.

Blood Glucose↗
PubMed1993

Effect of intravenous dopamine on blood pressure and plasma insulin in hypertensive patients.

Eleven patients with moderate to severe hypertension were pre-treated with oral labetalol 800-1200 mg/day for one week, prior to receiving two i.v. infusions of dopamine 1-3 micrograms/kg/min each of 30 min each, before and after the i.v. bolus injection of metoclopramide 30 mg. There were washout periods before and after the metoclopramide administration. Dopamine induced a significant decrease of blood pressure from 172/104 to 153/94 mm Hg without altering heart rate, and it increased the plasma insulin level from 8.3 to 12.1 microU.ml-1. Metoclopramide did not itself affect blood pressure or plasma insulin, but it did block the hypotensive response and rise in plasma insulin due to dopamine. We conclude that the pharmacological actions of intravenous dopamine on the cardiovascular system and on insulin secretion may be mediated by dopaminergic receptor stimulation.

Blood Glucose↗
PubMed1991

Purification of a procollagenase-activator present in medium of cultured guinea pig carrageenin granuloma.

Activation of procollagenase constitutes a crucial event in collagenolytic activity regulation. In this study we have purified by DEAE-cellulose, Ultrogel AcA-44, and zinc chelate sepharose chromatographies, a procollagenase-activator from the culture medium of the guinea pig carrageenin granuloma model. On SDS-PAGE, the activator migrates as a principal band of Mr approximately 44,000. The molecule activates procollagenase from human lung fibroblasts in a concentration dependent manner and an enhancement of collagenase activity of trypsin-treated crude culture medium was observed. A loss of about 50% of its activity occurs after heating. In addition, this activator degrades gelatin and casein. All these data suggest that this procollagenase-activator might be stromelysin. The activator was found in both phases of the granuloma, at 7 days when collagen is actively deposited and an important proportion of the collagenolytic activity remains in latent form; and at 14 days, when this enzymatic activity is fully expressed.

Animals↗
PubMed1990

Detection of antibodies against avian antigens in bronchoalveolar lavage from patients with pigeon breeder's disease: usefulness of enzyme-linked immunosorbent assay and enzyme immunotransfer blotting.

The study reported here evaluated the usefulness of the enzyme-linked immunosorbent assay (ELISA) in the detection of antibodies against pigeon antigens in the serum and bronchoalveolar lavage (BAL) of patients with clinical, radiological, and functional evidence of interstitial lung disease (ILD) with and without pigeon breeder's disease (PBD). The results were compared with those obtained by the simultaneous use of counterimmunoelectrophoresis (CIE) in the same patients. In PBD, ELISA detected antibodies against pigeon's sera in both serum and BAL in 100% of patients, while CIE failed to detect the antibodies in the serum of one patient and in most of the samples of BAL. In addition, we used enzyme immunotransfer blotting to determine the number of epitopes in pigeon serum recognized by antibodies present in serum and BAL. There was a heterogeneous response in both fluids, but the reaction pattern demonstrated that patient's sera recognize to-25 different pigeon epitopes. We conclude that ELISA is a highly sensitive and specific method for the detection of antibodies against pigeon antigens in the serum and BAL of patients with PBD and that the host response involves a great number of avian antigens.

Alveolitis, Extrinsic Allergic↗
PubMed1990

An evaluation of food group intakes by Mexican-American children.

Food group daily servings were examined for 3,436 children who participated in the Mexican-American portion of the 1982-1983 Hispanic Health and Nutrition Examination Survey (HHANES). Mean daily servings of 40 foods and food groups were calculated for four age groups: 1 to 2 years, 3 to 5 years, 6 to 11 years, and 12 to 17 years. The HHANES food servings data were combined into four major groups and compared with recommended servings for children. Mean daily servings of the milk group exceeded the recommended two to three servings for younger children but were low for teenagers. Meat group servings (including eggs and nuts/legumes) exceeded the recommended two daily servings for all age groups, whereas bread group intakes averaged 70% to 80% of a recommendation of four servings but only half of a recommendation of six servings. Intakes of fruits and vegetables were lowest, averaging only 33% to 47% of a recommended four servings, or 26% to 38% of a recommended five servings. Servings of all four groups were lowest for teenagers. A dietary score, based on the number of servings from each of the four groups, was developed for each child. Mean dietary scores ranged from 55% (teenagers) to 70% (toddlers and preschoolers) of the recommended score. According to these analyses, dietary guidance for Mexican-American children should focus on increasing intakes of fruits and vegetables and on encouraging more nutritious food choices by teenagers.

Adolescent↗
PubMed1988

Effects of fructose feeding on blood parameters and blood pressure in impaired glucose-tolerant subjects.

The effects of fructose and glucose on selected blood parameters and blood pressure after 4 weeks of oral ingestion were investigated in nine impaired glucose-tolerant subjects (IGTS) and nine normal glucose-tolerant subjects (NGTS). The criteria for IGTS were (1) 1- or 2-hour postprandial glucose levels between 160 and 200 mg/dL (8.8 to 11.1 mmol/L); (2) compliance with the diet; and (3) no cardiac or renal complication. The mean increment in the area under the plasma glucose and insulin curves after a glucose load was significantly greater following glucose than following fructose ingestion in both IGTS and NGTS (p less than .05). Glycosylated hemoglobin was greater after glucose than after fructose ingestion in IGTS and NGTS (71 gm/L vs. 61 gm/L in IGTS; 61 gm/L vs. 59 gm/L in NGTS). Serum triglyceride level in IGTS fed glucose was 173 mg/dL (1.90 mmol/L), whereas in those fed fructose, it was 154 mg/dL (1.69 mmol/L). Serum cholesterol was also greater after glucose than after fructose ingestion in all subjects. However, the differences were not statistically significant. Urate, pyruvate, and lactate levels were significantly greater in IGTS fed glucose than in IGTS fed fructose. Systolic and diastolic pressures were lower in IGTS fed fructose than in IGTS fed glucose. The present study shows that a 4-week oral ingestion of moderate amounts of fructose appears to have more benefits than an equivalent glucose ingestion in both IGTS and NGTS. However, greater benefits were found in IGTS than in NGTS.

Blood Glucose↗
PubMed1987

Antibodies to ribosomal ribonucleoprotein. Prevalence in systemic rheumatic diseases and partial characterization of the antigen.

The prevalence of antibodies to ribosomal ribonucleoproteins (rRNP) was studied in patients with rheumatic diseases. Seven patients had precipitating antibodies against rRNP, 6 had systemic lupus erythematosus, one had primary Sjögren's syndrome. Anti-rRNP was not present in mixed connective tissue disease, rheumatoid arthritis, progressive systemic sclerosis, CREST, primary Raynaud's or normal control sera. A partial immunological identity precipitin line was present between (U1) nRNP and rRNP, but these were distinct in physicochemical properties. Western blot analysis of ribosomal extract using anti-rRNP IgG revealed 2 polypeptides called rA and rB which appear to be the important antigenic determinants.

Antibodies↗
PubMed1986

Entamoeba histolytica: specific antigen recognized by a monoclonal antibody.

Specific antigenic determinants on the membrane surface of Entamoeba histolytica that distinguish it from other Entamoeba species were demonstrated. Evidence for these antigenic determinants was obtained with a monoclonal antibody to E. histolytica which showed not only specificity but also sensitivity as demonstrated in enzyme linked immunosorbent assay. Immunofluorescence microscopy showed that the monoclonal antibody recognized an epitope present on the membrane surface of E. histolytica trophozoites. The epitope detected by the monoclonal antibody was present in three components of different molecular weight. These components may have a common precursor or may be the result of enzymatic degradation under the conditions tested.

Animals↗
PubMed1986

Surgical procedures for the treatment of baldness.

New surgical methods are now available for the correction of male pattern baldness. Standard techniques have been significantly refined during the past decade. These methods include punch autografts, strip grafting, scalp reduction, use of hair-bearing flaps, microsurgery, and various combinations of these techniques. A more recent refinement of hair transplantation is the use of minigrafts and micrografts. We present an overview of the advantages and indications for each procedure.

Adult↗