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T H Price

Publications and source records attributed to T H Price.

At least 73 records · Page 4Linked to original sources

Comparison of selenite F, Muller-Kauffmann tetrathionate and Rappaport's medium for salmonella isolation from chicken giblets after pre-enrichment in buffered peptone water.

Six hundred and eighty three samples of chicken giblets were examined for salmonellas. Three hundred and forty nine of these were neck and crop specimens and 224 were combined liver and heart samples. Two hundred and ten, in all, contained salmonellas. The technique of examination included pre-enrichment in buffered peptone water at 37 degrees C for 18 h and subculture to three enrichment media: Muller-Kauffmann tetrathionate, selenite F and Rappaport's magnesium chloride malachite green broth. Inocula from buffered peptone water to 10 ml of tetrathionate and selenite were 1 ml in each case. The inoculum from the pre-enrichment medium to 10 ml of Rappaport was 0.005 ml. Tetrathionate and selenite were incubated at 43 degrees C for 48 h. Rappaport's medium was incubated at 37 degrees C for 48 h. Subcultures from all three enrichment broths were made at 24 h and 48 h to brilliant green MacConkey agar. Selective agars were incubated at 37 degrees C for 24 h. The most successful technique for salmonella isolation used Rappaport's medium, which was significantly more efficient than either tetrathionate or selenite. This finding reinforces results obtained using sewage polluted natural water as test material and it is suggested that routine examination of environment samples for salmonellas could be based on Rappaport's medium alone. If S. typhi, S. dublin or subgenus III salmonellas were likely to be present in the sample, the technique described here would require modification.

Animals↗

Neutrophil-endothelial cell interactions on endothelial monolayers grown on micropore filters.

We have developed a technique for growing endothelial monolayers on micropore filters. These monolayers demonstrate confluence by phase and electron microscopy and provide a functional barrier to passage of radiolabeled albumin. Neutrophils readily penetrate the monolayer in response to chemotaxin, whereas there is little movement in the absence of chemotaxin. This system offers unique advantages over available chemotaxis assays and may have wider applications in the study of endothelial function.

Blood Vessels↗

The cost effectiveness of therapeutic and prophylactic leukocyte transfusion.

We analyzed the cost effectiveness of leukocyte transfusion in preventing death from infection during intensive chemotherapy for acute leukemia. Effectiveness was estimated with an odds-ratio analysis based on published results of controlled studies of therapeutic and prophylactic leukocyte transfusion. Cost estimates were based on blood-bank charges throughout the country. Calculations of effectiveness suggest that leukocyte transfusion might prevent 50 to 75% of early deaths from infection. Therapeutic transfusion would add approximately 10.9% to the hospital bill of the average bill of the average leukemic patient and cost $17.7 million annually nationwide. Prophylactic transfusion would add 35.2% to the hospital bill and cost $57.8 million annually. Mean cost-effectiveness ratios were $14,982 per life-year for therapeutic transfusion and $35,020 to $50,029 per life-year for prophylactic transfusion. The cost per additional life-year achieved with prophylactic rather than therapeutic leukocyte transfusion was $85,291. These data suggest that leukocyte transfusion is an extremely expensive technologic procedure.

Acute Disease↗

Salmonella isolation with Rappaport's medium after pre-enrichment in buffered peptone water using a series of inoculum ratios.

The ability of malachite green/magnesium chloride broth (Rappaport's medium) to isolate salmonellas from 25 ml quantities of sewage-polluted natural water was investigated. Samples were first pre-enriched in buffered peptone water and varying volumes of inoculum from the pre-enrichment culture were inoculated into Rappaport's broth. Inoculum ratios in the range 1:2000 to 1:10 were examined. The inoculum ratio denotes the ratio of the volume of inoculum to the volume of fluid medium into which it is introduced. Optimum results were obtained with the 1:2000 ratio, although the salmonella isolation rate was only slightly less with the 1:500 and 1:100 ratios. The 1:2000 inoculum ratio was obtained with a graduated loop holding approximately 0.005 ml of fluid. Use of a loop for inoculation has advantages in speed of performance and safety of manipulation.

Bacteriological Techniques↗

Faecal excretion of entero-pathogens in a Pakistani family returning to the U.K. after a visit to Rawalpindi.

The family consisted of two parents and five children. While the father remained in Cardiff, the mother and all the children visited Rawalpindi, Pakistan, for 6 weeks to stay with relatives. Travel was by flight from Heathrow airport to Pakistan and by a short road journey to Rawalpindi. Mrs M. - the mother - as a guest, did no cooking on the holiday. The house which they were living in had a piped water supply, thought to be treated. There was no flush toilet but a commode was available and was emptied daily. All the children had gastro-enteritis symptoms for 2-3 days after arrival. Ru M. - a daughter - had the most severe illness and was treated by a local doctor. Diarrhoea in the three girls persisted on return to U.K. A faecal swab from Ru M. showed her to be excreting S. typhi (degraded Vi phage type). She was admitted to hospital. Faecal samples from the remaining members of the family were taken and examined for entero-pathogens. The father, Fa. M., who had not left Cardiff, had negative stools and remained free from infection. All other family members were excreting one or more entero-pathogens, including a Campylobacter sp., three types of Sh. flexneri and one type of Sh. boydii. A subsequent faecal sample revealed that one of the male children, A.M., was excreting S. typhi phage type B2. The two typhoid infections were apparently unconnected.The media used for microbiological diagnosis in this incident are discussed and contrasted with those employed for routine Salmonella examination of environmental samples. The advantages of selenite F in clinical diagnosis are noted.Antibiotic therapy was used for both typhoid cases but was not employed for the Shigella infections. The clinical condition of those involved in this incident might well have failed to arouse suspicion and the question arises whether food handlers returning from holiday in tropical and subtropical areas should have bacterological investigations before going back to their employment.

Adult↗

Laboratory induced variations in a standardized Salmonella isolation method.

Four microbiologists from four European laboratories came together to a single laboratory for two weeks and during that period examined 100 samples of minced meat artificially contaminated with salmonellae and 100 naturally contaminated samples using a standardized technique. No significant differences were found between the results obtained by the different analysts with 92 to 97 of the artificially contaminated and 30 to 42 of the naturally contaminated samples being found positive. Over a further period of eight weeks, these analysts examined the same number of samples in their own laboratories again using an identical procedure. There were no significant containing approximately 100 salmonellae per gram but significant differences (43 to 93) were found in isolation rates from the artificially contaminated samples copntaining approximately 1 salmonella per gram. The differences in findings between the first and the second part of the experiments may have been caused fairly by variations in media preparation, temperature of incubators, storage conditions of media and thawing conditions of samples etc., and secondly by differences in working conditions such as performing only one task during two weeks in contrast to examining the samples as part of the daily routine. At high levels of contamination, these factors do not appear to have an important influence on the performance of a laboratory.

Animals↗

Comparison of selenite F, Muller-Kauffmann tetrathionate and Rappaport's medium for the isolation of salmonellas from sewage-polluted natural water using a pre-enrichment technique.

Three enrichment broths, selenite F, Muller-Kauffmann tetrathionate and Rappaport, were examined for their efficiency in salmonella isolation. The three media, prepared from single ingredients in the laboratory, were compared with their commercial equivalents. Laboratory-prepared media were more efficient for isolating salmonellas from sewage-polluted natural water samples. A pre-enrichment stage using buffered peptone water was employed throughout the investigation. The size of inoculum from the pre-enrichment medium was relevant to successful salmonella isolation. Inocula studied were 1 ml and one loopful (3 mm diameter loop). The smaller inoculum gave better results with Rappaport, the larger with selenite and tetrathionate. Using the optimal inocula, Rappaport was the most efficient enrichment broth of the three fluid media in this study.

Benzylidene Compounds↗

Salmonella isolation from hospital areas.

Evidence of the presence of salmonellas in a paediatric ward, a special care baby unit, a maternity unit and a hospital kitchen was obtained by culture of sewer swabs, faeces and food samples. The survey was designed to cause as little administrative interference as possible. The technical aspects of the survey did not strain laboratory facilities. Minimal secondary spread of salmonella infection was experienced.

Bacteriological Techniques↗

Neutropenia, inflammation, and the kinetics of transfused neutrophils in rabbits.

A rabbit model was used to study the effects of neutropenia and inflammation on the intravascular distribution, survival, and tissue accumulation of transfused neutrophils. Donor blood labeled with [(3)H]thymidine was infused into normal or neutropenic (vinblastine treated) animals. Inflammation was created by subcutaneous implantation of polyvinyl sponges, some with added endotoxin. Initial circulating neutrophil pool recovery, survival, and inflammatory site accumulation of labeled neutrophils were measured. Neutropenia was associated with a relative increase in the marginal pool size, manifested by a diminished initial circulating pool (CNP) recovery of transfused cells. The CNP recovery was directly proportional to recipient neutrophil count. Neutropenia had no effect on the intravascular survival of transfused cells and was accompanied by only a modest decrease in the inflammatory site recovery of the transfused neutrophils (10.4+/-5.4 vs. 14.4+/-4.0% in normals). Inflammation in the form of subcutaneous polyvinyl sponges was accompanied by an increase in margination with initial CNP recoveries of 24.3+/-4.7 and 27.6+/-8.8% at zero and 4 h after implantation respectively (normal, 38.2+/-9.9%). Transit through the CNP was hastened by inflammation with a t((1/2)) of 2.02+/-0.72 h (normal, 3.2+/-1.0 h). Addition of endotoxin to the sponges further perturbed cell kinetics. CNP recoveries were considerably lower and half-lifes were initially shorter and subsequently uninterpretable in studies done after endotoxin sponge insertion. Inflammatory site accumulation was markedly diminished to 7.4+/-1.9% of injected neutrophil label in the endotoxin sponge animals, suggesting that many of the transfused cells were functionally unavailable rather than marginated. These studies demonstrate that neutropenia and inflammation with or without endotoxin markedly alter the kinetics of transfused neutrophils and that CNP recovery of transfused cells is not necessarily predictive of their inflammatory site accumulation.

Agranulocytosis↗

Neutrophil kinetics in chronic neutropenia.

Quantitative studies of bone marrow neutrophil pool sizes and production rates and of blood neutrophil kinetics were performed in 16 patients with chronic neutropenia without splenomegaly. Marrow netrophil cellularity was determined from a ferrokinetic estimate of marrow normoblasts and from neutrophil-erythroid ratios determined from marrow sections. Postmitotic pool turnover was derived from the postmitotic pool size and transit time, the latter determined from 3H-thymidine neutrophil emergence time. Blood neutrophil kinetics were studied with 32P-diisopropylfluoophosphate-labeled autologous neutrophils. Mitotic pool size was basal or below basal in 12 of the 16 patients. The turnover of the post-mitotic neutrophils was subbasal in 6, basal in 7, and above basal in 3 patients. Blood neutrophil turnover was within the normal range in 8 patients and decreased in 8. The degree of ineffective granulocytopoiesis was assessed by comparing the relative size of the mitotic pool, postmitotic pool turnover, and blood turnover. On this basis, 13 of the 16 patients showed appreciable degrees of ineffective granulocytopoiesis. Ineffective neutrophil production occurred both early and late in neutrophil development. These studies indicate that most patients with chronic neutropenia without splenomegaly lack a proliferative marrow response to the neutropenia and suggest that ineffective granulocytopoiesis is a common feature of this disorder.

Adult↗

Blood kinetics and in vivo chemotaxis of transfused neutrophils: effect of colllection method, donor corticosteroid treatment, and short-term storage.

To evaluate effect of collection technique and short-term storage on in vivo cell function, neutrophils were collected from 53 normal subjects by phlebotomy (PB), intermittent flow centrifugation (IFC), or filtration leukopheresis (FL), stored 0 or 1 day, labeled with 32P-diisopropylfluorophosphate, reinfused into the donor, and blood kinetics and/or skin chamber accumulation of labeled cells measured. The blood kinetics of unstored PB and IFC cells were similar; the kinetics of unstored FL cells were markedly abnormal. The percent of infused neutrophils localizing to the skin chamber was 0.1, 0.06, and 0.006 for unstored PB, IFC, and FL cells, respectively. One-day storage substantially decreased chamber accumulation of infused neutrophils. Donor steroid pretreatment had no effect on chamber results. Thus, in vivo chemotactic ability of IFC neutrophils is slightly impaired, whereas that of FL cells is severely impaired. One-day storage of either cell concentrate causes further cell damage.

Adrenal Cortex Hormones↗

Myelofibrosis with complex chromosome abnormality in a patient with erythrocytosis due to hemoglobin Rainier and treated with 32P.

A patient with familial erythrocytosis associated with Hemoglobin Rainier, and previously treated with 32P, developed myelofibrosis with a hyperdiploid chromosome clone in the myeloid cells (51,XX,+1,2q-(q33),+6,+9,+11,-19,+20q+,+mar 1.) This transformation from a benign disorder of differentiated erythrocytes to a malignant disorder may have been secondary to radiophosphorus therapy.

Chromosome Aberrations↗

Autoimmune neutropenia in systemic lupus erythematosus.

The mechanism of granulocyte depletion in a patient with systemic lupus erythematosus and neutropenia was investigated. Neutrophil kinetic studies showed a shortened intravascular survival (t1/2 of 1.6 hours) in the face of an increased marrow neutrophil pool. IgG bound to the patient's neutrophils, measured by the Fab antiF(ab')2 assay, was nearly three times normal. The IgG neutrophil-binding activity of the patient's serum was elevated in serial samples obtained over two years. In addition, his serum was able to opsonize normal neutrophils for ingestion by other neutrophils as detected by 14C-1-glucose oxidation. Enhanced IgG PMN-binding activity was observed with sucrose density gradient fractions of the patient's serum containing either large complexes (19S or greater in size), intermediate complexes (between 7S and 19S), or monomeric IgG. Only the momomeric IgG fraction from the patient's serum, however, opsonized normal neutrophils for ingestion by other neutrophils. These results support the hypothesis that anti-cell antibodies were responsible for the neutropenia in this patient by opsonizing neutrophils for ingestion by other phagocytic cells.

Agranulocytosis↗

Neutrophil transfusion: effect of storage and of collection method of neutrophil blood kinetics.

The kinetics in blood of autologous neutrophils collected by phlebotomy, filtration leukapheresis (FL), or intermittent-flow centrifugation (IFC), labeled with 32P-diisopropylfluorophosphate, and stored at 4 degrees C for up to 2 days were measured in 41 normal subjects. Mean initial recovery for unstored IFC cells was 34.0%, compared to 7.9% for unstored FL cells. Blood half-lives were 4.1 and 2.7 hr for unstored IFC and FL cells, respectively. With neutrophils collected by phlebotomy and stored in whole blood for 1-2 days, posttransfusion recoveries and blood half-times were significantly decreased. Storage of both IFC and FL preparations resulted in only moderate kinetic abnormalities in comparison to the unstored cells. These studies indicate that the ability of unstored IFC cells to circulate is basically normal, whereas that of unstored FL cells is significantly impaired. The data further suggest that these neutrophil concentrates might be stored for 1-2 days prior to transfusion.

Blood Preservation↗