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Biomedical subjects

M J Cruz

Publications and source records attributed to M J Cruz.

17 recordsLinked to original sources
PubMed2006

An amplified sandwich EIA for the measurement of soy aeroallergens.

BACKGROUND: Soy hull low-molecular-weight (SHLMW) allergens were responsible for the soy asthma epidemics in Barcelona, with one 7.5 kDa protein (Gly m 1) being the main IgE-binding component. The aims of this study were to develop a sensitive sandwich enzyme immunoassay (EIA) using rabbit polyclonal antibodies to measure low levels of SHLMW allergens, and to compare this method with the previously described human IgE EIA-inhibition technique. METHODS: IgG was isolated from serum of rabbits immunized with a chromatographically purified SHLMW extract (SHLMWE). Antibody-binding profiles were compared with those of human IgE anti-soy protein antibodies by Western blot analysis. An amplified sandwich EIA was developed using the purified SHLMWE as a calibration standard. Results were expressed in nanograms per millilitre. To compare the two assays, 54 air samples were analysed by both methods. RESULTS: SDS-PAGE of the SHLMWE revealed four bands of 6, 8, 15 and 17 kDa. Gly m 1 in the SHLMWE was identified by fingerprinting. The detection limit of the assay was 40 pg/mL. The two methods correlated well (r=0.89; P<0.001). The allergen concentration was detected in all 54 (100%) samples by the sandwich EIA but in only 37 (68.5%) by the EIA inhibition. CONCLUSIONS: The amplified sandwich EIA for SHLMW components has a high sensitivity and appeared to be a useful tool for the measurement of airborne SHLMW allergens, even at relatively low concentrations. Moreover, the method uses rabbit antibodies at high dilutions and does not require human sera, with limited availability and quantitative and qualitative pool-to-pool variability.

Air Pollutants↗
PubMed2005

Occupational asthma related to mouse allergen exposure and rhinoconjunctivitis due to collagenase inhalation in a laboratory technician.

We describe the case of a 27-year-old patient working in a research laboratory, who developed occupational asthma to mouse proteins and presented symptoms of rhinoconjunctivitis caused by manipulation of collagenase. Specific inhalation challenge confirmed the diagnosis of occupational asthma to mouse proteins, whereas specific challenge with collagenase only evoked symptoms of rhinitis and conjunctivitis. SDS-PAGE and Western blot analysis for collagenase showed that the patient's IgE antibodies bound specifically to a protein with a molecular weight of 92 kDa. Hence, this was an unusual case of double sensitization. The sensitization to collagenase presented in this report may represent a new occupational disease in technicians working in medical or research laboratories.

Adult↗
PubMed2004

Validation of specific inhalation challenge for the diagnosis of occupational asthma due to persulphate salts.

BACKGROUND: The significant value of tests used to certify the diagnosis of occupational asthma due to persulphate salts remains uncertain. AIMS: To validate the specific inhalation challenge (SIC) test for the diagnosis of occupational asthma. METHODS: Eight patients with occupational asthma due to persulphate salts, eight patients with bronchial asthma who were never exposed to persulphate salts, and ten healthy subjects were studied. Clinical history taking, spirometry, bronchial challenge with methacholine, skin prick testing to common inhalant allergens and persulphate salts, total IgE levels, and SIC to potassium persulphate were carried out in all subjects. The SIC used increasing concentrations of potassium persulphate (5, 10, 15, and 30 g) mixed with 150 g of lactose. Patients tipped the mixture from one tray to another at a distance of 30 cm from the face for 10 minutes in a challenge booth. RESULTS: The SIC was positive in all subjects with persulphate induced asthma and in one patient with bronchial asthma who had never been exposed to persulphate salts. Sensitivity was 100% (95% CI 67.6 to 100) and specificity was 87.5% (95% CI 52.9-97.8) when patients with occupational asthma due to persulphate salts were compared with those with bronchial asthma never exposed to persulphate salts. CONCLUSIONS: SIC to persulphate salts performed according to the protocol described appears to be useful for the diagnosis of occupational asthma secondary to inhalation of this substance.

Adult↗
PubMed2003

[Occupational asthma in food packers].

This report describes the case of a 26-year-old woman working in a fish-processing factory who developed bronchial asthma when transferred to the packing department. Various tests, including a specific bronchial challenge test, confirmed a diagnosis of occupational asthma. While polyvinyl chloride (PVC) appeared to be the causal agent in this case, the possible role of other etiological agents is also discussed. Although occupational asthma in food packers is rare, we nonetheless consider it important to recognize this type of asthma given the widespread use of PVC.

Adult↗
PubMed2001

Chemical monitoring and evaluation of the water quality of the Douro River at the Crestuma-Lever dam.

Water taken from the Crestuma-Lever dam on the Douro River was evaluated considering the Portuguese Decree-law no. 236/98 of 1st August, 1998. This paper presents the metrological characteristics, validation of analytical methodologies and the data obtained from seasonal samplings. The test parameters selected are: temperature, pH, chloride, conductivity, carbon dioxide, alkalinity, hardness, oxidability, dissolved oxygen, BOD5, total suspended solids, sulfide, phosphate, silica, ammonium, nitrite, nitrate, sulfate, sodium, potassium, calcium, magnesium, iron, manganese, copper and zinc. From data analysis we can conclude that the water presented the following characteristics: a pH situated in the neutral zone; a median mineralization; a medium hardness; well oxygenated water; and a carbonate hardness exclusively due to bicarbonates. The temperature, pH, dissolved oxygen, ammonia, chlorides, sulfates, copper, zinc and BOD5 were compared with the legal limits presented in annexes XXI and I of Decree-law 236/98. The results relating to total hardness, nitrites, calcium, magnesium, sodium, potassium, aluminium, sulfides and oxidability were compared with the legal values in annex VI as there are no limits relating to these parameters in annexes XXI and I.

Environmental Monitoring↗
PubMed2000

Sarcocystis levinei infection in Philippine water buffaloes (Bubalus bubalis).

Ultrastructural studies of sarcocysts obtained from Philippine water buffaloes revealed the presence of the commonly reported macroscopic species, Sarcocystis fusiformis, and the microscopic species Sarcocystis levinei (Dissanaike A, Kan S. Studies on Sarcocystis in Malaysia. I: Sarcocystis levinei n.sp. from the water buffalo Bubalus bubalis. Z Parasitenkd 1978;55:127-38), (Huong L, Dubey J, Uggla A. Redescription of Sarcocystis levinei Dissanaike and Kan, 1978 (Protozoa: Sarcocystidae) of the water buffalo (Bubalus bubalis). J Parasitol 1997;83:1148-52). The globular to oval microscopic cysts commonly observed in the muscles of the diaphragm and neck exhibit compartmentalized arrangement of zoites with septal partitions and measure 13-48 microns in diameter. The parasitophorous vacuolar membrane of sarcocyst bears minute and hair-like villar protrusions measuring 2.3-2.75 microns long emanating at certain distances from the primary cyst wall and lack microfilaments. Villar protrusions have expanded to dome-shaped base measuring 0.33-1.6 microns long by 0.22-1.0 micron wide, and intermediate and tapering distal segments bent approximately 90 degrees and run parallel to the cyst surface. The distal segments at some areas join to form conical tufts. The primary cyst wall bears numerous prominent undulations that are arranged in small clusters. The ground substance is 0.42-0.57 micron thick. This paper documents the first report of S. levinei in Philippine water buffaloes possessing the type 7 cyst wall.

Animals↗
PubMed2000

Detection of specific antibodies to pigeon serum and bloom antigens by enzyme linked immunosorbent assay in pigeon breeder's disease.

BACKGROUND: Pigeon breeder's disease is an extrinsic allergic alveolitis in the lungs of sensitised people, caused by hypersensitivity reactions to inhaled pigeon antigens. Antigens from different sources of the animal are used for diagnostic purposes, with serum being the most widely used. Bloom is rarely used; very little is known of its antigenicity and diagnostic performance, particularly when used with the enzyme linked immunosorbent assay (ELISA) method, which is the most popular test as it permits measurement of the antibody response. METHODS: To (a) standardise an ELISA for the measurement of specific IgG against pigeon serum and pigeon bloom extract; (b) to establish reference values for specific IgG in 73 non-exposed controls, (c) to show the presence of specific IgG against pigeon serum and bloom in serum samples of 17 patients with bird fancier's lung and 11 asymptomatic fanciers, and (d) to study the similarity of the two antigen sources by cross reactivity experiments. RESULTS: Reference values of specific IgG were defined with the 97.5 percentile (367.9 U/ml for pigeon serum and 953.7 U/ml for pigeon bloom extract). Of symptomatic patients 100% had values higher than the cut off for both antigens. In asymptomatic fanciers values were higher than the cut off for pigeon serum in 45% and bloom extract in 54%. Cross reactivity experiments showed that the two antigens differed in antigenic content although some components may be common to both. CONCLUSION: The ELISA methods used proved to be useful tools for evaluating specific IgG antibody responses against both antigens. The diagnostic performance of both ELISA methods performed with these antigen sources was similar, showing very high sensitivity but moderate specificity. Although some antigenic similarity was found between pigeon serum and bloom extract, cross reactivity studies showed that various antigens seemed to be specific to the bloom extract. However, the antigens responsible for pigeon breeder's disease seem to be present in both antigenic sources.

Adult↗
PubMed2000

An amplified ELISA inhibition method for the measurement of airborne soybean allergens.

BACKGROUND: Measurement of the soybean aeroallergen in Barcelona and other cities where soybean is unloaded is of increasing importance in controlling population exposure and evaluating the influence of such exposure on the persistence of asthma symptoms. OBJECTIVE: The aims of the study were: (1) to standardize an amplified ELISA inhibition method for the quantification of soybean aeroallergen and (2) to compare this method to a previously described RAST inhibition method. METHODS AND RESULTS: An amplified competitive ELISA inhibition method with a biotin-streptavidin system was carried out using a pool of sera from soybean-sensitized patients. The results were expressed as U/ml using a low-molecular-mass soybean allergen as reference standard. Reproducibility was calculated by statistically comparing the slope of the regression lines of the standard curve of 4 consecutive assays and by determining the coefficient of variation (CV) of the percent inhibition data for each point of several independent standard curves, each from the same assay (intra-assay) and also from a separate assay (inter-assay). No significant differences in the slopes were obtained by analysis of covariance (ANCOVA) F = 1.04. The CV between assays varied between 4 and 22% (for the assay range used in the reference standard) and was greater than the CV within assays (5-10%). Only values with a CV(%) smaller than 20% were considered acceptable. 78.5% of the samples satisfied this criterion. The RAST inhibition and ELISA inhibition methods were compared by difference plots from the values of 338 air filter eluates. The intraclass correlation coefficient was 0.456 (p < 0.001). After the results of both methods were classified as lower and higher than 165 U/m(3), the kappa index was 0.46 (p < 0.001). CONCLUSIONS: The data obtained in the present study are comparable to those reported from other similar immunoassays. Moreover, despite the difficulty in comparing air-sampling values from different laboratories, the kappa index may be taken to represent fairly good agreement beyond chance between both methods. All these data demonstrate that the present immunoassay is useful for measuring airborne soybean aeroallergens and can also be applied to evaluate the relationship between exposure and the development of asthma symptoms.

Air Pollutants↗
PubMed2000

Utility of the antibody response to a conjugated Haemophilus influenzae type B vaccine for diagnosis of primary humoral immunodeficiency.

Antibody response to an Haemophilus influenzae type b (Hib)-conjugated vaccine was studied in 59 healthy adults (mean age: 32 yr) and 22 patients with humoral immunodeficiencies (mean age: 32 yr) to determine its usefulness in the diagnosis of defective antibody formation. Twenty of the healthy adults and nine of the patients were also immunized with a pneumococcal vaccine. Serum specific antibodies were measured by ELISA. Adequate response to both vaccines was defined using the lower limit of the two-tailed 90% probability interval of postimmunization specific IgG of the healthy adults. By using this cutoff, responders were considered to be those with an absolute increase in anti-Hib IgG titers higher than 2.28 microgram/ml, and in anti-Streptococcus pneumoniae IgG higher than 395 arbitrary units/ml. With these criteria, 85% (50 of 59) of the healthy adults responded with anti-Hib IgG and 75% (15 of 20) with anti-pneumococcal IgG. All healthy adults receiving both vaccines responded to at least one. None of the patients with humoral immunodeficiencies responded to either vaccine. Evaluation of the antibody response to both the Hib and pneumococcal vaccines may facilitate the diagnosis of humoral immunodeficiency and selection of patients to receive immunoglobulin therapy.

Adolescent↗
PubMed2000

Sarcocystis spp infection in Philippine water buffaloes (Bubalus bubalis).

In a survey of sarcocysts in muscle tissues obtained from 142 water buffaloes, 65% of the carcasses had sarcocysts. Macroscopic and two forms of microscopic sarcocysts, the spindle-shaped or fusiform sarcocysts commonly occurring in the muscles of the esophagus, throat and limbs, and the globular to oval-shaped sarcocysts which were the dominant form in the diaphragm and cervical muscle tissues were noted. Ultrastructural analysis of macroscopic and microscopic sarcocysts and their cyst wall revealed two distinct species of Sarcocystis: the macroscopic species, Sarcocystis fusiformis which has been previously reported in Philippine carabaos possessing highly dendritic cauliflower-like projections emanating from the primary cyst wall, with annulated microfilaments and numerous electron dense granules: and the Sarcocystis levinei (Dissanaike and Kan, 1978) Huong, Dubey and Uggla. 1997 exhibiting a cyst wall with undulating and hair-like villar protrusions with expanded or dome-shaped base, intermediate finger-like, and distal tapering segments which at some points join to form conical tufts. Our findings represent the first report of S. levinei in the country supported with ultrastructural analysis of the sarcocysts and cyst wall, and likewise refute earlier published reports that all microscopic sarcocysts in Philippine carabaos are developing forms of the macroscopic species, S. fusiformis. Histopathological changes such as displacement and necrosis of the surrounding host muscle tissue were observed with macroscopic sarcocysts and histologically processed tissue samples containing microscopic fusiform sarcocysts. Necrotic myofibrils and mitochondria were evident in ultrathin sections.

Animals↗
PubMed1999

Pierre Robin sequences: secondary respiratory difficulties and intrinsic feeding abnormalities.

OBJECTIVE: There is considerable variation in opinion regarding the optimal management of patients with Pierre Robin sequence (PRS). No single method of airway intervention or feeding strategy is universally appropriate and effective. This study was performed to examine methods used for airway and feeding management and to identify specific problems encountered. STUDY DESIGN: A retrospective study of 252 patient charts between 1989 and 1997 at Children's Hospital of Wisconsin. METHODS: Patient information was collected regarding perinatal history, genetics evaluation, and airway and feeding evaluations and intervention. A group of 47 patients was determined as having PRS. RESULTS: Secondary respiratory difficulties, defined as respiratory abnormalities in addition to the expected PRS obstruction, were identified in 23% of patients. Also, intrinsic feeding abnormalities not associated with airway obstruction were identified in 11% of patients. Analysis by Fisher's Exact Test revealed patients with a syndromic diagnosis to have a significantly higher rate for tracheotomies and gastrostomy tube placement (P = .041, and P = .0004, respectively). Syndromic patients were also found to have significantly lower Apgar scores and longer hospital stays. Positioning techniques, tongue-lip adhesion, and tracheotomy were also employed effectively with specific indications and specific difficulties that need to be considered. CONCLUSION: Patients with PRS require thorough airway and feeding evaluation. Those with additional syndromic diagnoses demonstrate higher rates of more invasive interventions. Patients with PRS must undergo individualized approaches with consideration of multiple factors for successful management.

Apgar Score↗
PubMed1999

Specific antibody response against the 23-valent pneumococcal vaccine in patients with alpha(1)-antitrypsin deficiency with and without bronchiectasis.

OBJECTIVE: To assess the specific antibody response against polyvalent pneumococcal vaccine in patients with alpha(1)-antitrypsin deficiency (AATD) and respiratory infections. DESIGN AND PARTICIPANTS: We investigated specific IgG, IgG1, and IgG2 antibody responses against the 23-valent antipneumococcal vaccine in 18 patients with AATD phenotype PiZZ, 9 of whom had bronchiectasis and 4 a history of recurrent pneumonia, and compared them with a control group of 40 healthy volunteers. INTERVENTIONS: Blood samples were drawn just prior to and 3 weeks after immunization. MEASUREMENTS AND RESULTS: Quantification of specific IgG and its subclasses was performed by an enzyme-linked immunosorbent assay. For patients with AATD, mean increases in specific antipneumococcal titers were 4.7-fold (25 to 75% quartiles, 2.5- to 6.8-fold) for total IgG, 3.2-fold (1.2- to 4.9-fold) for IgG1, and 2.1-fold (1.8- to 3.7-fold) for IgG2. For the control group, the values were 3.3-fold (1.8- to 5.8-fold) for total IgG, 2. 5-fold (1.9- to 3.4-fold) for IgG1, and 3.1-fold (1.9- to 4.5-fold) for IgG2; differences were not significant. Patients with bronchiectasis showed a tendency toward higher levels of IgG subclasses than both control subjects and patients without bronchiectasis; however, there was a tendency toward lower postvaccination serum levels of specific antipneumococcal IgG, IgG1, and IgG2 in patients with bronchiectasis compared with patients without bronchiectasis, but this trend did not reach statistical significance. Three of the four patients with recurrent pneumonia did not show an appropriate IgG2 response. CONCLUSIONS: These results suggest that, as a group, patients with AATD have a preserved antibody response against pneumococcal polysaccharides. Patients with bronchiectasis show a tendency toward a decreased antibody response, even with increased serum levels of most Ig types. Individuals with an impaired IgG2 response seem to be at increased risk of recurrent pneumonia. Considering the pernicious effect of pulmonary infections on these patients and the preserved antibody response in a majority of them, pneumococcal vaccination should be recommended to patients with AATD.

Adult↗
PubMed1997

Blood sample processing effect on eosinophil cationic protein concentration.

BACKGROUND: Asthma is considered to be an inflammatory disease. The most important cell involved in the inflammation is the eosinophil. These cells and their mediators, such as eosinophil cationic protein (ECP), are potential markers of the inflammation's severity. Eosinophil cationic protein may be used for monitoring antiasthma treatment. It is well known that sample processing conditions can affect the ECP blood levels. OBJECTIVE: The aim of this work is to study the effect of temperature, time, and anticoagulants on ECP levels. METHODS: We studied five asthmatic patients and five healthy controls. We obtained three different blood samples from each subject, one with heparin, one with EDTA, and one without anticoagulant. To evaluate the effect of temperature, serum samples were clotted for an hour, one at 0 degree C, one at room temperature, and the other at 37 degrees C. Plasma (heparin and EDTA) samples were treated as follows: one was immediately centrifuged, and two were stored for an hour, one at 0 degree C, and the other at room temperature. Eosinophil cationic protein levels were measured by fluoroimmunoassay (CAP-System ECP FEIA Pharmacia). RESULTS: A higher temperature during blood clotting resulted in a higher ECP concentration. There were no differences between ECP determination in serum samples and plasma samples with heparin, under the same conditions of time and temperature; so clotting may not be necessary for ECP release in vitro. Eosinophil cationic protein was not released in plasma samples with EDTA, neither at 0 degree C nor room temperature. CONCLUSIONS: More studies must be done to clarify the mechanism of the ECP release in vitro.

Adult↗
PubMed1997

Characterization of specific immunoglobulin G (IgG) and its subclasses (IgG1 and IgG2) against the 23-valent pneumococcal vaccine in a healthy adult population: proposal for response criteria.

The aim of the study was to standardize an enzyme-linked immunosorbent assay (ELISA) method for the quantification of immunoglobulin G (IgG) and its subclasses (IgG1 and IgG2) against the 23-valent pneumococcal vaccine and to establish the criteria for a normal response to the vaccine. Forty healthy individuals (20 women and 20 men; mean age, 29 years) were studied. All were vaccinated with the 23-valent pneumococcal vaccine; blood samples were drawn just prior to and 3 weeks after immunization. Quantification of specific IgG and its subclasses was performed by an ELISA with the vaccine as the antigen. The linearity of the ELISA method was demonstrated by the similar slopes of the linear regression lines generated from the titration of sera with different antibody concentrations. The specificity of the antibodies against the vaccine was demonstrated by (i) an absorption test with pneumococcal vaccine, (ii) a cross-reactivity experiment with Haemophilus influenzae type b polysaccharide, and (iii) affinity chromatography with protein A-Sepharose. Response to the vaccine was defined by using the lower level of the 90% probability interval (one-tailed) for postimmunization-specific IgG, IgG1, and IgG2. By using this cutoff, responders were considered to be those with an absolute increase in antibody titers higher than 395 arbitrary units/ml for IgG, 0.350 A450 units for IgG1, and 0.314 A450 units for IgG2. Overall, 20 (50%) subjects had IgG, IgG1, and IgG2 responses, 9 (22.5%) had IgG and IgG2 responses, 4 (10%) had IgG1 responses, 3 (7.5%) had IgG and IgG1 responses, and 4 (10%) were nonresponders. Ninety percent of our population responded to the 23-valent pneumococcal vaccine. Up to 10% of healthy individuals may respond to an IgG subclass without significant increases in total IgG titers. The ELISA method that is described may be useful for evaluating the specific antibody response against polysaccharides.

Adult↗
PubMed1996

IgG subclass deficiencies associated with bronchiectasis.

Only a small number of patients with IgG subclass deficiencies (IgGSD) have been observed to have bronchiectasis. Moreover, in the series of patients with bronchiectasis, IgGSD have not been found at any frequency, and the etiology of bronchiectasis remains unclear in 29 to 49% of cases. Serum concentrations of total IgG, IgA, and IgG subclasses as well as pulmonary function were measured in 65 patients (aged: 10 to 74 yr) with bronchiectasis of unknown etiology. An ELISA test was performed to quantify subclasses 1 through 4 using subclass-specific antihuman monoclonal antibodies. IgG subclass estimation in a healthy population with age-stratified normal ranges was derived from 100 adults, 37 children aged between 10 and 12 yr, and 27 adolescents aged between 13 and 16 yr. Serum concentrations of specific IgG antibodies to Haemophilus influenzae type b capsular polysaccharide (Hib-PRP) were also assayed by an ELISA test in 19 of the patients (10 with IgGSD and nine with non-IgGSD) and in 58 healthy individuals before and 3 wk after immunization with Hib-PRP conjugated to meningococcal outer membrane protein complex (OMPC). Thirty-one patients (48%) had low serum concentrations of one or more IgG subclasses (19 IgG2 deficiencies, 2 IgG3 deficiencies, 3 IgG4 deficiencies, and 7 combined subclass deficiencies). All patients showed increased levels of total IgG, IgG1, and IgA, but this rise was significantly higher in patients without IgGSD. Patients with IgGSD showed impaired antibody response to Hib-PRP compared with patients with non-IgGSD and the control group. IgGSD, particularly IgG2 deficiency, are not an unusual cause of bronchiectasis. Therefore, serum levels of IgG subclasses must be assayed whenever other causes of bronchiectasis have been ruled out.

Adolescent↗
PubMedDate not supplied

Computed tomography vs. magnetic resonance imaging of acute bacterial sinusitis: a rabbit model.

PURPOSE: Computed topography (CT) and magnetic resonance imaging (MRI) are important, both clinically and in a research setting, in assessing bacterial sinusitis (BS). The use of CT scanning to evaluate sinus opacification in a reversible model of rabbit acute sinusitis has been reported. MRI offers the potential for better visualization of soft tissue and fluid changes within the paranasal sinuses. MRI has potential as a research tool in animal models of sinusitis. This article compares the use of CT and MRI in measuring maxillary sinus opacification in rabbits during experimental, reversible BS. MATERIALS AND METHODS: In 2 independent trials, New Zealand White rabbits were imaged for baseline anatomy, and BS was generated by sinus inoculation with Staphylococcus aureus. Serial imaging was performed as a measure of the progression and resolution of BS during the trials. Two experienced, independent reviewers then scored each CT and MRI for percent opacification of the maxillary sinus. These scores were analyzed to assess the degree of agreement between the reviewers. RESULTS: The correlation coefficients for CT and MRI were 0.6816 and 0.3584, respectively. The Z-statistic comparing these correlation coefficients was significant (P < .0001), indicating that CT is a more precise measure of reversible BS in this rabbit model. Differences in mean scan time and cost per scan were also significantly different (P < .0001), with CT being both quicker and less expensive. CONCLUSIONS: Greater interobserver consistency of scan interpretation, with less time and cost, make CT the preferred tool for measuring BS in this rabbit model. Attributes of MRI such as better resolution of fluid-tissue interfaces and custom surface coil design for visualization of specific anatomic structures are discussed as they may increase the effectiveness of MRI as an imaging modality in future sinusitis research.

Acute Disease↗