Search PubMed⌕ Search

Biomedical subjects

R J Pierce

Publications and source records attributed to R J Pierce.

At least 91 records · Page 5Linked to original sources
PubMed1988

Tracheal papillomatosis treated with Nd-Yag laser resection.

We report a case of tracheal papillomatosis in a 69-year-old woman who presented with stridor and functional evidence of large airway obstruction. She was successfully treated by endobronchial resection using a Neodymium Yag laser. This provided lasting symptomatic relief of dyspnea. Respiratory papillomatosis is a disease predominantly of the childhood larynx and its presentation with predominant tracheal involvement late in life is extremely uncommon. Laser therapy provides an extremely effective treatment modality for this condition.

Aged↗
PubMed1987

Functional properties of a rat monoclonal IgE antibody specific for Schistosoma mansoni.

A rat monoclonal antibody of IgE isotype (B48-14) raised against Schistosoma mansoni has been generated by the fusion of mesenteric lymph node cells from LOU/M rats immunized with a preparation of adult schistosome worms and IR973F nonsecreting rat myeloma cells. Investigation of the in vitro effector functions of this IgE antibody showed a high level of cytotoxicity against S. mansoni schistosomula in the presence of eosinophils, macrophages, and platelets. A significant level of protection (40 to 60%) against a challenge infection with S. mansoni cercariae was achieved by passive transfer experiment of B48-14 IgE to naive recipient rats. By immunoprecipitation, B48-14 IgE antibodies were shown to react with an antigen of 26 kDa present in excretion-secretion products of schistosomula, previously described as a potential immunogen eliciting a protective IgE response against schistosomiasis.

Animals↗
PubMed1987

A purified 28,000 dalton protein from Schistosoma mansoni adult worms protects rats and mice against experimental schistosomiasis.

We have purified a 28,000 dalton (P28) protein from Schistosoma mansoni adult worms and used it to immunize Fischer rats. Immunofluorescence assays demonstrated that the P28 antigen was mainly located in the parenchyma of the schistosomulum and of the adult worm, including the dorsal spines of the parasite. Western blot analysis revealed that this antigen was present in three species of schistosomes: S. mansoni, S. japonicum, and S. bovis. The antibody response raised against this protein was able to kill S. mansoni schistosomula in in vitro cytotoxicity assays in the presence of rat eosinophils. The inhibition of this cytotoxic activity by an aggregated myeloma IgG2a indicated that one of the major isotypes involved in this in vitro model is IgG2a. The passive transfer of P28 antisera induced a significant level of protection against experimental infection. Moreover, we have immunized Fischer rats and BALB/c mice with the purified 28,000 dalton protein and observed a marked decrease (up to 70%) in the parasite burden in both experimental infection models.

Animals↗
PubMed1987

The isotypes of antibody responsible for the 'late' passive transfer of immunity in rats vaccinated with highly irradiated cercariae.

The role of different antibody isotypes in the transfer of protection with serum from rats vaccinated with irradiated cercariae were investigated by immunoadsorption of IgG, IgG2a and IgG2c, and by heating at 56 degrees C to remove IgE. Only depletion of IgG2a reduced the levels of vaccine-induced immunity transferred, whereas immunity transferred by infection serum was reduced by both IgG2a and IgE depletion. It was also shown that exposure to irradiated parasites did not lead to either specific or non-specific induction of an IgE response. The successful passive-transfer experiments using serum from non-resistant 25 week-infected rats into recipient animals demonstrated that the waning of resistance observed in 25 week-infected rats was not due to a failure of the humoral response to protective antigens.

Animals↗
PubMed1987

Helper T cells induced by a purified 28-kilodalton antigen of Schistosoma mansoni protect rats against infection.

Schistosoma mansoni adult worm 28-kilodalton (kDa) proteins were separated on polyacrylamide slab gels, recovered by electrophoretic elution, and used to immunize Fischer rats. After the second or third injection, inguinal lymph node T lymphocytes were propagated in vitro for 4 weeks in the presence of syngeneic antigen-presenting cells and adult worm antigens in medium containing interleukin-2. After this period of culture, 99% of the cells expressed the W3/13+ surface phenotype and 93% of the cells expressed the W3/25+ surface phenotype. These cells were then tested for their in vivo functional activity after transfer to Fischer rats that had been either infected with S. mansoni cercariae or immunized with the 28-kDa purified protein. In each case, an increase of S. mansoni-specific antibodies was observed. Whereas anti-28-kDa antibodies were only detectable at day 40 postinfection in controls injected with normal T lymphocytes, they appeared as early as day 13 postinfection when the animals received 28-kDa protein-specific T lymphocytes. This led to an effective protection of infected rats (45 to 85%) which correlated with the increase in S. mansoni-specific antibodies. These results therefore demonstrate that the 28-kDa protein possesses epitopes capable of activating helper T cells, which confer a strong protective immunity by enhancing the production of cytotoxic antibodies. The stimulation of the 28-kDa-specific T cells with recombinant proteins suggests that the major epitopes are located toward the carboxylic end of the molecule.

Animals↗
PubMed1987

Measurement of effective pulmonary blood flow by soluble gas uptake in patients with chronic airflow obstruction.

A study was designed to assess the accuracy and reproducibility of rebreathing and single breath soluble gas uptake measurements of effective pulmonary blood flow (Q) in patients with airways obstruction. Both rebreathing (RB) and single breath (SB) estimates of Q were compared with direct Fick and thermodilution (TD) measurements of cardiac output at rest and during exercise in eight patients with chronic, poorly reversible airflow obstruction with mean FEV1 65% predicted and mean FEV1/FVC 53%. The mean (SD) resting values obtained were QRB 3.47 (0.46), QSB 4.75 (1.15), QFick 4.77 (0.97), and QTD 5.15 (0.98). QRB was significantly lower than the other three estimates, which did not differ significantly from each other. Exercise produced significant increases in all four estimates for the group. The mean exercise values were QRB 6.23 (1.19), QSB 7.62 (1.97), QFick 8.97 (1.96), and QTD 9.09 (1.00), both QRB and QSB being significantly less than QFick and QTD. Analysis of variance of the rest, exercise, and combined data showed highly significant relationships with the TD and Fick measurements for both QRB and QSB over the range of values studied. In addition, the reproducibility of QRB and QSB was assessed in 15 other patients with chronic airflow obstruction (mean FEV1 42% predicted, FEV1/FVC 43%) and in 10 normal subjects. The coefficients of intrasubject variability for a single measurement for QRB were 8.7% in normal subjects and 10.2% in patients and for QSB were 11.7% in normal subjects and 16.1% in patients. The group differences from morning to afternoon, between days, and over a month were not significant in the normal subjects. In the patients QRB was slightly higher in the afternoon than in the morning of the same day, but the differences between days and over a month were not significant for either test. Although both tests detected the increase in pulmonary blood flow during exercise, the single breath test was more accurate at rest. Some underestimation was present for rebreathing at rest and for both tests during exercise, but this can be allowed for. In patients with mild airflow obstruction the reproducibility of the soluble gas uptake methods was similar to that of invasive catheter methods of cardiac output estimation. The single breath test in particular was, however, less reproducible in patients with more severe airflow obstruction, and the rebreathing method may be more useful for detecting increases in pulmonary blood flow in these patients.

Adult↗
PubMed1987

GP38, P28-I and P28-II: candidates for a vaccine against schistosomiasis.

Three antigens protective against Schistosoma mansoni have been extensively characterized. The schistosomulum surface antigen GP38 possesses an immunodominant carbohydrate epitope of which the structure has been defined. Protection can be achieved via the transfer of monoclonal antibodies recognizing the epitope or by immunization with anti-idiotype monoclonal antibodies. The glycan epitope is shared with the intermediate host, Biomphalaria glabrata as well as being present on other molluscs, including the Keyhole Limpet. A group of molecules at 28 kDa were initially characterized in adult worms and shown to protect rats and mice against a challenge infection. One of these molecules, P28-I, was cloned and expressed in E. coli, yeast and vaccinia virus. The recombinant antigen significantly protected rats, hamsters and baboons against a challenge infection. P28-I is a glutathione-S-transferase and the recombinant antigen produced in yeast exhibits the enzyme activity and has been purified to homogeneity by affinity chromatography. A second P28 antigen, P28-II, has also been cloned, fully sequenced and expressed. This recombinant antigen also protects against S. mansoni infection.

Animals↗
PubMed1986

[A new ELISA method for the diagnosis of toxoplasmosis. Assay of serum IgM by immunocapture with an anti-Toxoplasma gondii monoclonal antibody].

The diagnosis of acute toxoplasmosis is based exclusively on the detection of IgM anti-Toxoplasma antibodies. The principal of the immunoenzymatic test reported here is the capture of serum IgM antibodies which are detected indirectly by the sequential addition of antigen and a monoclonal antibody directed against the immunodominant epitope at the surface of the tachyzoite. This test combines the sensitivity of enzyme-based assays and the specificity of monoclonal reagents and represents an important contribution to the diagnosis of Toxoplasma gondii infection.

Acute Disease↗
PubMed1986

Lobar occlusion in the preoperative assessment of patients with lung cancer.

Bronchial occlusion during exercise was used to predict the functional effects of subsequent pulmonary resection in six high risk patients with lung cancer and severe airflow obstruction. Each patient underwent transnasal fibreoptic bronchoscopy whilst cycling in steady state at a load which had been selected as equivalent to walking at a brisk pace for that patient. The effects on minute ventilation and oxygen uptake were observed during occlusion of the bronchus to the diseased lobe. If the patient was able to continue cycling and maintain the same work load during occlusion this was regarded as indicating that he would withstand resection of the occluded lung tissue. In five of the patients, postoperative studies were performed. All were able to maintain the same level of steady state exercise postoperatively as that maintained during bronchial occlusion preoperatively. Resection resulted in a decrease in static lung volumes. Other routine whole lung function tests, walking capacity and incremental exercise indices, however, were largely unchanged.

Aged↗
PubMed1986

Congenital lobar emphysema requiring surgery in adult life.

We report a case of congenital lobar emphysema requiring surgery in early adult life to relieve respiratory symptoms of late onset. Regional lung function studies helped to predict the outcome of surgery which was successful in relieving symptoms.

Adolescent↗
PubMed1985

Translation of Schistosoma mansoni antigens in Xenopus oocytes microinjected with mRNA from adult worms.

Oocytes from Xenopus laevis microinjected with RNA isolated from Schistosoma mansoni adult worms translated antigens recognized by sera from infected rats, humans, and from immunized rabbits. The pattern of immunoprecipitated proteins analysed by SDS-polyacrylamide gel electrophoresis was species specific in rats. Serum from infected Fischer rats recognized antigens of 20, 27 and several bands in the 50-60 kDa range whereas serum from infected Brown Norway rats also immunoprecipitated major bands at 29, 43 and 100 kDa. Human infection sera gave a very variable pattern of immunoprecipitation not apparently dependent on the patients' age. At least 20 different antigenic species could be identified ranging from 14 to 150 kDa. Some S. mansoni antigenic proteins could be isolated from the membrane fraction of the oocytes whereas notably the 29 kDa band was present mainly in the soluble fraction. N-Glycosylation of S. mansoni antigens occurred as evidenced by the effects of tunicamycin treatment and concanavalin A binding. A multiple series of bands between 50 and 60 kDa, present in the membrane fraction, were glycosylated and secreted from the oocytes. Monoclonal antibodies to larval stage surface antigens failed to immunoprecipitate oocyte translation products, but sera absorbed with live schistosomula identified at least three putative surface antigens of 100, 43 and 29 kDa. However, the 29 kDa molecule was neither synthesized into membranes, nor secreted from oocytes.

Animals↗
PubMed1985

In vitro synthesis of a 28 kilodalton antigen present on the surface of the schistosomulum of Schistosoma mansoni.

Adult Schistosoma mansoni proteins were fractionated on polyacrylamide slab gels, recovered by electrophoretic elution and used for immunization of Fischer rats. Three antisera recognizing, respectively, 28, 78 and 85 kDa antigens were obtained. The 28 kDa antigen was found among the in vitro translation products from adult worm RNA, and among the 125I-labelled surface antigens of S. mansoni schistosomula. The isoelectric point of the 28 kDa antigen was 6.3-6.5. The 28 kDa antiserum mediated a cytotoxic activity against schistosomula when used in an in vitro assay in the presence of a purified eosinophil cell population.

Animals↗
PubMed1985

Regulatory role of a peptide from the second constant domain of immunoglobulin G--II. In vitro effect on granuloma formation around S. mansoni eggs.

Previous studies have shown that hydrolysis of IgG by proteases secreted by S. mansoni schistosomula release peptidic fragments which inhibit various macrophage functions. Several peptides from the second constant domain of IgG reduced granuloma formation in vitro with spleen cells from mice infected by S. mansoni eggs of the parasite. The maximal inhibitory effect was obtained by the tripeptide Thr-Lys-Pro (TKP). Inhibition occurred at the early stage of the granulomatous response. Among the cells involved only the adherent cell population was inhibited by the peptide. In addition, TKP-inhibited macrophage migration towards soluble egg antigens (SEA), suggesting that the reduced granuloma reaction by TKP is the result of the interaction between the peptide and macrophages. Injection of TKP into infected mice reduced the in vitro granulomatous response obtained using their spleen cells. This suggests an in vivo interaction between TKP and cells from the monocyte lineage. Moreover, the substitution of TKP on its NH2 or COOH terminal (Acetyl-TKP and TKP-amide) did not affect its in vitro activity. The latter result is of particular importance in the in vivo application of the peptide, at present under investigation.

Amino Acid Sequence↗
PubMed1985

Microbial contamination of domiciliary nebuliser therapy equipment.

Fifty-two outpatients requiring domiciliary nebulised bronchodilator therapy were studied to determine the frequency and degree of contamination of nebuliser solutions and equipment. In 32 of the 52 patients (61%) nebuliser solutions and/or aerosols were contaminated. The degree of contamination was greater than that of ambient air in 90% of the contaminated aerosols. Diluent solutions were more frequently contaminated than salbutamol solutions (51% vs. 9%) and the organisms isolated from the solutions frequently correlated with those in aerosols. Gram-negative bacilli, particularly Pseudomonas species, were the most frequently isolated organisms.

Aerosols↗
PubMed1984

Role of IgE receptors in effector function of human eosinophils.

After analysis of the technical parameters of the rosette assay with human IgE-coated erythrocytes, Fc epsilon receptors for IgE (Fc epsilon R) on human peripheral blood eosinophils were compared to Fc epsilon R on lymphocytes and monocytes. Antibodies directed against Fc epsilon R on lymphocytes and monocytes inhibited the IgE rosettes formed by eosinophils from hypereosinophilic patients, which suggests that Fc epsilon R on eosinophils were antigenically related to Fc epsilon R on lymphocytes and monocytes. Fc epsilon R on human eosinophils were shown to participate in the killing effect of Schistosoma mansoni schistosomula in vitro in the presence of purified eosinophils from highly hypereosinophilic patients (blood counts greater than 3000/mm3) and anti-schistosomula IgE antibodies present in S. mansoni-infected patient sera. Similar levels of inhibition of cytotoxicity were obtained after preincubation of eosinophils with aggregated human IgE or with anti-Fc epsilon R antibodies, whereas preincubation with aggregated IgG or with anti-C3b receptor antibodies did not decrease the killing effect for schistosomula targets. This IgE-dependent cytotoxic capacity seemed restricted to eosinophils with an abnormally low density ("hypodense" cells) present only in highly hypereosinophilic patients. These observations might be related to nonparasitic situations in which increased levels of IgE and tissue or blood eosinophils are observed.

Antilymphocyte Serum↗
PubMed1984

Allergens of Schistosoma mansoni. II. Fractionation and characterization of S. mansoni egg allergens.

The interaction of Schistosoma mansoni crude soluble egg antigen (SEA) with IgE antibodies in sera from S. mansoni-infected mice, rats and humans has been studied by the radioallergosorbent test (RAST) and the Prausnitz-Küstner (PK) technique. IgE antibodies recognizing egg antigens were present as early as day 21 after the infection in the mouse sera and day 28 in rat sera. IgE in sera of infected humans reacted with antigenic components in the Mr range 70,000-150,000 and focusing as a broad peak in the pH range 4.5-6.5 as measured by RAST. SDS-PAGE followed by western blotting showed the presence of major components at molecular weights of 117,000 and 35,000-43,000. In the PK test, using mouse sera, components focusing in the alkaline pH range also gave a positive reaction. Most of the allergenic activity was bound by concanavalin A-Sepharose and by wheat germ agglutinin-Ultrogel. IgE in serum from an infected non-permissive host (the Fischer rat) apparently recognized egg-stage-specific allergen as indicated by differences in the time course of the IgE response to egg allergens compared to the adult material. When analyzed by SDS-PAGE and western blotting with day 45-infected rat serum, SEA showed some qualitative and quantitative differences to adult worm antigen. Molecules at molecular weights between 25,000 and 30,000 and at about 43,000 in SEA reacted with rat serum IgE and were absent from adult worm antigen. The allergenic similarities between egg and adult worm are discussed.

Allergens↗
PubMed1983

Comparison of wet and dry aerosol salbutamol.

Wet aerosol and metered dose inhaler (MDI) modes of inhalation of salbutamol were compared in ten asthmatic patients with severe, reversible airways obstruction and in ten chronic bronchitic patients with severe, poorly reversible airways obstruction. The responses to cumulative doses to 800 micrograms (8 x 100 micrograms) by MDI and 10 mg (4 x 0.5 ml of 0.5% standard solution) by wet aerosol were studied. From maximum expiratory flow-volume curves, measurements were made of FEV1, FVC, PEFR, Vmax 50% and Vmax 75%, and pulse and blood pressure responses to cumulative doses of salbutamol were measured. In both groups of patients there was no significant difference between the two modes of inhalation either for each treatment interval or for the maximal response in any of these indices.

Aerosols↗