Search PubMed⌕ Search

Biomedical subjects

R Moss

Publications and source records attributed to R Moss.

At least 73 records · Page 4Linked to original sources
PubMed1989

The role of parasite fecundity and longevity in the success of Trichostrongylus tenuis in low density red grouse populations.

The prevalence of the caecal threadworm Trichostrongylus tenuis in red grouse in the north of Scotland was high despite low grouse densities. Prevalence, intensity and aggregation of threadworms was higher in old than in young grouse. Infections were long-lasting: populations of adult worms could survive for over 2 years in grouse, with little mortality. Parasite egg output decreased with the age of a worm population, largely as a result of a decrease in the fecundity of ageing female worms. Seasonal variations in worm fecundity were also evident. However, there was no evidence of an intensity-dependent decrease of worm fecundity with increasing worm numbers in either captive or wild grouse. The long life and high reproductive capacity of T. tenuis probably contribute to its effective transmission and high prevalence.

Animals↗
PubMed1989

Factors affecting the establishment of the caecal threadworm Trichostrongylus tenuis in red grouse (Lagopus lagopus scoticus).

The resistance of captive reared red grouse to Trichostrongylus tenuis was measured as the proportion of ingested infective 3rd-stage larvae which failed to develop to adult worms. Individual grouse showed wide, repeatable variations in resistance. Seasonal variations may also have occurred. Red grouse acquired little or no effective immunity to reinfection after challenge with a single dose of infective larvae. In trickle-dosed grouse, however, adult worms weakly inhibited the establishment of incoming larvae in an intensity-dependent fashion. Despite this, the proportion of larvae established in trickle infections was similar to that in single-dose challenges.

Analysis of Variance↗
PubMed1989

Development and survival of the free-living stages of Trichostrongylus tenuis, a caecal parasite of red grouse Lagopus lagopus scoticus.

In the laboratory, yields of infective 3rd-stage larvae of Trichostrongylus tenuis were determined by temperature when moisture was adequate. On the moor, eggs in caecal faeces did not develop to infective larvae during the winter. In summer, development did occur and yields of infective larvae were related to temperature: greatest yields were obtained when mean monthly soil surface temperatures ranged between 7.6 and 10.3 degrees C. Rainfall was unimportant, as was desiccation. During summer the mean monthly mortality of infective larvae was 44% but over winter survival was negligible.

Animals↗
PubMed1989

Multi-organ damage resulting from experimental faecal peritonitis.

1. Using specific-pathogen-free New Zealand White rabbits, we have compared the effects of faecal peritonitis over a period of 5 h in eight test animals with eight controls in which a sham operation was performed. 2. There was morphological damage to lungs, liver and spleen of test animals. Lung capillaries and sinusoids of the liver showed occlusion by cell debris and leucocytes, with endothelial damage. The lungs also showed alveolar epithelial disruption, basement membrane exposure and type II pneumocytes lacking lamellar bodies. In the liver there was fibrin deposition and swollen Kupffer cells. The spleen showed degranulating neutrophils, fibrin deposits, platelet aggregates and activated macrophages, with no damage to the endothelium. 3. There was no morphological damage to the kidney or heart of test animals or to any organs of sham-operated animals. 4. There were mixed anaerobes and aerobes in faecal material used to induce peritonitis. Cultures of liver, spleen and kidney isolated four different types of micro-organisms. Blood cultures showed two types of micro-organisms. Cultures of lung and heart showed one type of micro-organism. 5. The presence of micro-organisms in an organ could not be correlated with the degree of histological damage to that organ. 6. In test animals an early significant reduction in circulating leucocytes and platelets was sustained for the duration of the experiment with significant diffuse intravascular coagulation. 7. There was no change in test animal neutrophil adhesiveness until 120 min, when significant reduction was observed. 8. Serum phospholipase A2 (EC 3.1.1.4) activity in the test group showed a threefold increase at 300 min.

Animals↗
PubMed1989

Chylothorax: a complication of the nephrotic syndrome.

A 50-yr-old man with the nephrotic syndrome developed a chylothorax that was shown to be due to transdiaphragmatic movement of chylous ascites. Because a significant number of patients with nephrotic syndrome have been reported to have chylous ascites, the possibility that chylothorax is due to movement of chylous ascites into the pleural space should be considered prior to surgical intervention directed toward repair of the thoracic duct.

Chylothorax↗
PubMed1989

Nonopsonic antibodies in cystic fibrosis. Pseudomonas aeruginosa lipopolysaccharide-specific immunoglobulin G antibodies from infected patient sera inhibit neutrophil oxidative responses.

Antibody opsonins from cystic fibrosis (CF) patients were investigated using nonmucoid and mucoid lipopolysaccharide (LPS) immunotype 1 Pseudomonas aeruginosa as bacterial ligands and PMN phagocytes. CF sera were compared to normal sera, polyvalent PA LPS hyperimmune globulin, and isotype switch variant monoclonal antibodies (MAbs) specific for type 1 PA LPS. Sera from PA-infected CF patients (CF PA+) had elevated levels of PA LPS and alginate IgG antibodies and promoted significantly greater antibody-dependent PMN chemiluminescence responses than sera from uninfected CF patients (CF PA-) or normal human sera (NHS). After adjustment for autologous IgG PA LPS antibody content, however, CF PA+ sera had less antibody-dependent opsonic activity than sera from CF PA- patients (P less than 0.025) or NHS (P less than 0.0025), suggesting qualitative opsonic defects of IgG PA LPS antibodies in CF PA+ sera. Antigen-specific immunoprecipitation of PA LPS antibodies enhanced opsonization by 40% of CF PA+ sera while uniformly reducing that from CF PA- sera (P less than 0.01), indicating LPS-specific nonopsonic antibodies in some CF PA+ sera. Alginate antibodies were not critical opsonins in most uninfected CF patient sera. PA LPS IgG antibodies isolated by immunoaffinity chromatography from NHS, hyperimmune globulin, and CF PA- sources were opsonic and had greater activity at equal antigen-binding concentration than identical antibodies isolated from infected CF patients (P less than 0.01-0.05); the majority of isolates from CF PA+ sera did not promote PMN oxidative responses above nonopsonic baseline. A potential isotypic basis for these findings was supported by differences in PMN responses to PA opsonized with MAbs of identical specificity but differing isotypes. PA LPS-specific IgG antibodies inhibiting PMN oxidative responses in infected patient sera demonstrate antigen-specific immunomodulation of host responses by chronic bacterial parasitism in CF, which may play a role in the pathophysiology of lung disease.

Antibodies, Bacterial↗
PubMed1989

Pentoxifylline reduces pulmonary leucostasis and improves capillary patency in a rabbit peritonitis model.

This study examines the changes in pulmonary leucostasis and capillary ultrastructure in 18 rabbits divided into three groups. Those in the first group were sham operated, and those in the second and third groups underwent peritonitis induction; those in the latter group were treated with pentoxifylline (PTF). White blood cells (WBC) were counted, and tissue area, total capillary area, and capillary patency were measured from electron micrographs of lung tissue. Pulmonary WBCs were 1.2 per unit field in the sham group, 9.7 in the test group (P less than 0.001 compared with sham), and 2.5 in the PTF group (P less than 0.001 compared with sham). Capillary patency was 53 +/- 5% in the sham group, 12 +/- 4% (P less than 0.001 compared with sham) in the test group, and 24 +/- 2% (P less than 0.001 compared with sham) in the PTF group. Pentoxifylline treatment attenuates pulmonary leucostasis, pulmonary capillary occlusion, and endothelial and epithelial damage associated with peritonitis in rabbits. This study shows that PTF warrants investigation into its potential protective effects on the lungs in clinical sepsis.

Animals↗
PubMed1988

Sputum changes associated with therapy for endobronchial exacerbation in cystic fibrosis.

We sought to define objective indicators of the resolution of Pseudomonas aeruginosa endobronchial infection in patients with cystic fibrosis. We prospectively studied 75 patients admitted for treatment of a pulmonary exacerbation and quantitated sputum bacterial density, DNA content, and the concentration of albumin and total protein in sputum, and compared these values with clinical evaluation. Eleven of the 75 patients had systemic signs, fever, and leukocytosis, which we arbitrarily defined as due to endobronchial infection. At the end of hospitalization, these 11 patients were afebrile, had peripheral leukocyte counts in the normal range, and were judged improved. Sputum P. aeruginosa density, DNA content, and total protein content on admission were similar in the two illness groups. Hospitalization and parenteral antibiotic administration for an average of 14.6 days were associated with improved pulmonary function in all 75 subjects (P values for forced vital capacity, forced expiratory volume at 1 second, and peak expiratory flow rate were all less than 0.001). With improvement, there was a decrease in sputum P. aeruginosa density (mean of both groups decreased from 10(7.80) CFU/g on admission to 10(5.96) CFU/g; P less than 0.001), and a decreased DNA concentration (overall mean 4.73 +/- 4.75 on admission to 2.76 +/- 2.49 mg/g; P less than 0.002). The decrease in sputum total protein concentration for both groups was not significant (overall mean 60.5 +/- 48.4 to 43.9 +/- 38.2 mg/g; P = 0.06). Sputum albumin concentrations did not change in either group. We conclude that in cystic fibrosis subjects with a pulmonary exacerbation, bacterial density, sputum DNA and protein content decrease with hospitalization and parenteral antibiotic therapy. At the end of treatment, these indices of sputum infection and inflammation correlate with improved pulmonary function and clinical improvement. These changes are independent of the presence or absence of fever on admission.

Adolescent↗
PubMed1988

Reproducibility of skin prick testing with allergen extracts from different manufacturers.

Allergen extracts for skin prick testing (SPT) are available from several manufacturers. Although these solutions are specified according to well-defined internal company standards, there is no generally accepted overall standardization. To assess the comparability of skin prick test solutions of various manufacturers, we compared extracts of nine different allergens from four companies by SPT in 29 children sensitive to one or more of the allergens, in a double blind fashion. RAST (Pharmacia) and EAST (Kallestad) were determined in simultaneous blood samples. Allergen extracts were also examined by rocket immunoelectrophoresis for their content of major allergens. Skin reactions, assessed by mean diameter of wheals, to identical allergen extracts varied significantly between the four vendors (P less than 0.05-0.001). Correlation between RAST and EAST was good for all allergens except birch pollen and mugwort. Content of the major allergen in corresponding extracts varied significantly between the different companies (less than 1%-2000%). These data underline the need for international reference extracts as intracompany standardization of test solutions alone is not enough to yield general reproducibility of skin prick test results.

Adolescent↗
PubMed1988

Thrombosis of the renal artery of a small, solitary kidney: successful return of renal function after prolonged anuria.

In the presence of a single functioning kidney, renal artery obstruction produces anuria, which can require hemodialysis. If the problem is diagnosed immediately and surgical intervention is not delayed, revascularization of the ischemic kidney is usually successful. Few authors, however, have reported the return of function to a small solitary kidney after occlusion lasting longer than 2 hours. We describe a case that involved thrombosis of the renal artery to an 8-cm solitary kidney; a successful endarterectomy was performed 29 hours after the onset of anuria. This case shows that the reversibility of renal ischemia is not necessarily determined by either the duration of occlusion or the size of the affected kidney.

Journal Article↗
PubMed1987

A phospholipase inhibitor modifies the pulmonary damage associated with peritonitis in rabbits.

Peritonitis has been produced in rabbits by the spreading of 5 ml of caecal contents throughout the peritoneal cavity. After sacrifice at 5 h, electron microscopy revealed a increase of 600% in PMN and 1200% in lymphocytes in the pulmonary capillaries of the test animals when compared to the sham operated group. The pulmonary capillaries in the test group showed a 27% reduction in their luminal area, which was associated with a 73% reduction in their patency due to occlusion by WBC and cell debris. In addition there was endothelial and epithelial disruption with basement membrane exposure. The PMN were degranulated and adherent to the pulmonary endothelium. Pretreatment with the phospholipase inhibitor, mepacrine, significantly attenuated these responses, so that there was only an increase of 200% in PMN and 450% in lymphocytes in the lungs with no evidence of degranulation or adhesion to the pulmonary endothelium. Furthermore there was no change in capillary luminal area when compared to the sham operated group. In addition there was only slight damage to the endothelium and epithelium with no exposure of the basement membrane. Peripheral WBC in both the test and mepacrine groups showed a similar 62% and 75% reduction after 5 h when compared to baseline values. The sham group did not show this change. These results suggest that phospholipase inhibition plays an important role in attenuating the pulmonary response to faecal peritonitis and may be of potential benefit in treating clinical septicaemia.

Animals↗
PubMed1987

Results in resident cholesteatoma surgery: a review of 85 cases.

A review of all patients with cholesteatoma operated on by the residents of the New York Eye and Ear Infirmary under the attending supervision of the Otology Service between 1980 and 1984 was done. Of 130 resident cases, 85 had documented follow-up 1 year or longer and were included in the study. Recurrence rates were 18% with canal wall down (CWD) and 43% with canal wall up (CWU) techniques. Considering other forms of failure (such as precholesteatoma, tympanic membrane perforation, and chronic infection), overall failure rates were 33% (CWD) compared with 82% (CWU). Cholesteatoma recurrence failure rates were higher in patients under the age of 20 (33%) than over the age of 20 (19%). Overall failure rates were 61% and 37% for younger and older patients, respectively. Due to the high failure rate with canal wall up techniques in resident hands, it is recommended that resident service cases be treated with canal wall down technique, especially in the younger age group.

Age Factors↗
PubMed1987

Interobserver variance in clinical scoring for cystic fibrosis.

Multicenter clinical research would benefit from a simple, reliable scoring system for comparison of the clinical status of patients at different centers. In this study, five physicians performed simultaneous, independent scoring of 41 individuals with cystic fibrosis using the Doershuk modification of the Shwachman-Kulczycki scoring system for history, physical examination, and nutrition, and the Birmingham scoring system for chest roentgenograms. These were added together to obtain a clinical score. Interobserver variance of the scores was calculated. Mean individual observer variance from the consensus mean was 1.6-2.9 score points of a possible 25 for each category, 4.5-6.0 of a possible 100 for the total score. Coefficient of variance about the mean was approximately 10 percent for the individual categories, 6.7 percent for the total score. We concluded that the interobserver variance of this scoring system is within acceptable limit for most clinical studies. The total consensus score correlated with the NIH clinical score, chest roentgenogram score alone, and predicted values for forced vital capacity and FEV1 with a high degree of confidence.

Activities of Daily Living↗