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B A Harrison

Publications and source records attributed to B A Harrison.

At least 37 records · Page 2Linked to original sources
PubMed1995

Production and characterization of monoclonal antibodies to Actinobacillus pleuropneumoniae serotype 5b.

Monoclonal antibodies specific for capsular polysaccharide (CPS) and lipopolysaccharide (LPS) of A. pleuropneumoniae serotype 5b were generated by hybridoma cells and selected by indirect ELISA of culture supernatants with purified and structurally defined LPS and CPS preparations and their synthetic conjugates. It was shown in this study that at least one monoclonal antibody, 3B4, presented 100% specificity and recognized all A. pleuropneumoniae serotype 5 field strains tested in a dot-ELISA assay.

Actinobacillus pleuropneumoniae↗
PubMed1994

The clinical spectrum of critical illness polyneuropathy.

OBJECTIVE: To describe the entity of critical illness polyneuropathy and review our experience with six cases. DESIGN: We present case reports of six patients with polyneuropathy associated with critical illness, who received medical care at the Mayo Clinic between 1992 and 1994, and discuss similar cases from the literature. RESULTS: Critical illness may damage peripheral nerves. In previous studies, sepsis and multiorgan failure have been found to trigger a peripheral neuropathy. Of our six patients with critical illness polyneuropathy, all had a preceding severe bacterial infection or septic shock. In one patient who had long-term administration of vecuronium bromide and had received massive intravenous doses of corticosteroids, sural nerve and quadriceps muscle biopsy specimens were available; they revealed axonal neuropathy and notable myopathic changes, respectively. The outcome was good in patients who survived the critical illness. CONCLUSION: Polyneuropathy in critically ill patients may be a cause of severe generalized limb weakness and occurs in the setting of a sepsis syndrome. The long-term outcome is good in patients who recover from the underlying critical illness. Compression neuropathies may be a cause of permanent sequelae.

Acute Disease↗
PubMed1994

Managing risk to minimize liability.

Agencies undoubtedly face increased chances of investigation, yet risk management may be as simple as keeping good records and following standard operating procedures. One pilot program exemplifies how this can reduce an agency's liability exposure.

Documentation↗
PubMed1992

Female body size, parity, and malaria infection of Anopheles maculatus (Diptera: Culicidae) in peninsular Malaysia.

The relationship among body size (as indicated by wing length), age (as indicated by parity dissections), and malaria infection were observed in host-seeking Anopheles maculatus Theobald females collected in aboriginal villages of peninsular Malaysia. Both ELISA and salivary gland dissections were used to determine malaria infection. The wings of parous females were significantly longer than those of nulliparous females, suggesting that larger females live longer than smaller ones, and thus have a higher vectorial capacity. Body size differences were not detected between infected parous and uninfected parous females. Females infected with only oocysts were significantly larger than females infected with sporozoites. No correlation was found between the number of oocysts or sporozoites and body size in this small sample.

Animals↗
PubMed1992

Simple computer measurement of pulmonary VCO2 per breath.

Measurements of the volume of CO2 exhaled per breath (VCO2/br) are preferable to end-tidal PCO2, when the exhaled flow and CO2 waveforms may be changing during unsteady states, such as during alterations in positive end-expiratory pressure or alterations in cardiac output. We describe computer algorithms that determine VCO2/br from digital measurements of exhaled flow (including discontinuous signals common in anesthesia circuits) and CO2 concentration at the airway opening. Fractional concentration of CO2 is normally corrected for dynamic response and transport delay (TD), measured in a separate procedure. Instead, we determine an on-line adjusted TD during baseline ventilation. In six anesthetized dogs, we compared the determination of VCO2/br with a value measured in a simultaneous collection of expired gas. Over a wide range of tidal volume (180-700 ml), respiratory rate (3-30 min-1), and positive end-expiratory pressure (0-14 cmH2O), VCO2/br was more accurate with use of the adjusted TD than the measured TD (P less than 0.05).

Algorithms↗
PubMed1991

The effect of the depth of neuromuscular blockade on the haemodynamic response to tracheal intubation.

The effect of two different doses of vecuronium on the heart rate and mean arterial pressure response to tracheal intubation was compared in 32 adult ASA class I patients. It was found that the higher dose of vecuronium (2.5 X ED95) produced greater depression of the evoked electromyogram (P less than 0.01), and provided better intubating conditions (P less than 0.01) than the lower dose of vecuronium (1 X ED95). However, the heart rate and the mean arterial pressure response to tracheal intubation was similar with both doses. The results indicate that, within the range of neuromuscular blockade commonly used to facilitate tracheal intubation, the depth of neuromuscular blockade per se does not affect the haemodynamic response to intubation.

Adult↗
PubMed1991

Significance of circumsporozoite-specific antibody in the natural transmission of Plasmodium falciparum, Plasmodium vivax, and Plasmodium malariae in an aboriginal (Orang Asli) population of central peninsula Malaysia.

Two hundred and seventy-five Orang Asli volunteers living in nine villages in the Pos Legap Valley of Perak State, peninsular Malaysia, participated in a prospective study designed to characterize the epidemiological, parasitological, and entomological characteristics of Plasmodium falciparum, P. vivax, and P. malariae malaria transmission. Prevalence rates for the three plasmodial species at initiation of the study ranged from 56% in the 0-4-year-old age group to 0% in individuals over the age of 40. Entomological surveys were conducted, enabling us to determine mosquito salivary gland-positive rates and entomological inoculation rates of 1.2 infectious mosquito bites per person per month for P. falciparum, 2.4 for P. vivax, and 0.3 for P. malariae. Cumulative incidence rates over the 16 weeks of the study, following radical cure of all volunteers, were 22.5% for P. falciparum, 12.7% for P. vivax, and 1.5% for P. malariae. The median baseline antibody titer against the immunodominant repetitive B cell epitope of P. falciparum or P. vivax circumsporozoite protein was significantly higher for volunteers who did not become parasitemic. Volunteers were selected for further study if they had evidence of being challenged with P. falciparum sporozoites during the study, based on a two-fold or greater increase in antibody titer against the immunodominant repetitive B cell epitope of the circumsporozoite protein. Resistance to infection was seen in six of 10 individuals who had high (greater than 25 OD units) baseline ELISA titers, compared with only three of 24 individuals who had low baseline ELISA titers (chi 2 P less than 0.02). A similar analysis for P. vivax did not show a significant correlation.

Adolescent↗
PubMed1991

Comparative susceptibility of Southeast Asian Anopheles mosquitoes to the simian malaria parasite Plasmodium cynomolgi.

Seven Anopheles species/isolates were compared with Anopheles dirus (control) for susceptibility to Plasmodium cynomolgi B strain. The mean numbers of oocysts in paired replicates of An. dirus and An. takasagoensis were not significantly different. The remaining test species had significantly fewer mean numbers of oocysts than Anopheles dirus (P less than 0.01). Anopheles dirus had the highest percentage of mosquitoes infected with P. cynomolgi sporozoites (82%). Of the test groups, Anopheles dirus B and An. takasagoensis had the highest percentage of mosquitoes with sporozoites, 77 and 78%, respectively. Fewer than 50% of Anopheles maculatus E and An. maculatus B (NN isolate) had sporozoites in the salivary glands. Anopheles maculatus B (HK isolate) and Anopheles philippinensis were the least susceptible, with fewer than 30% having sporozoites in the salivary glands.

Animals↗
PubMed1990

A rapid sporozoite ELISA using 3,3',5,5'-tetramethylbenzidine as the substrate chromogen.

A modified version of the standard 2-site sporozoite enzyme-linked immunosorbent assay (ELISA) using 3,3',5,5'-tetramethylbenzidine (TMB) as the substrate chromogen solution was adapted for rapid detection and identification of Plasmodium falciparum and P. vivax circumsporozoite (CS) proteins. The TMB-ELISA was evaluated using sporozoites from experimentally infected mosquitoes and laboratory colonized uninfected mosquitoes. Our data indicate comparable sensitivity levels between the TMB-ELISA and the standard ELISA, i.e., 50 P. falciparum or P. vivax sporozoites/50 microliters of test solution. Reactions inherent to the method were specific and background reactivity was minimal. The TMB-ELISA is rapid (1 hr), simple, uses a minimal amount of monoclonal antibodies, and is suitable for use in a wide range of laboratories.

Animals↗
PubMed1990

Anopheles dirus species E: chromosomal and crossing evidence for another member of the dirus complex.

Cytogenetic and crossing data provide strong evidence for the existence of another species, dirus E in southwestern India, within the Dirus Complex of Anopheles. These findings are in accord with unpublished morphological observations. Our data suggest a significant genetic divergence between species E and its close relatives, An. dirus A, B and C in Thailand. These data also suggest that dirus E is an incipient sibling species of its geographically nearest relative, dirus D, and that it seemingly co-evolved through the process of allopatric speciation.

Animals↗
PubMed1987

Effect of temperature on the vector efficiency of Aedes aegypti for dengue 2 virus.

The effect of temperature on the ability of Aedes aegypti to transmit dengue (DEN) 2 virus to rhesus monkeys was assessed as a possible explanation for the seasonal variation in the incidence of dengue hemorrhagic fever in Bangkok, Thailand. In two laboratory experiments, a Bangkok strain of Ae. aegypti was allowed to feed upon viremic monkeys infected with DEN-2 virus. Blood-engorged mosquitoes were separated into two groups and retained at constant temperatures. Virus infection and transmission rates were determined for Ae. aegypti at intervals ranging from 4 to 7 days during a 25-day incubation period. Results of the first experiment for mosquitoes infected with a low dose of DEN-2 virus and maintained at 20, 24, 26, and 30 degrees C, indicated that the infection rate ranged from 25% to 75% depending on the incubation period. However, DEN-2 virus was transmitted to monkeys only by Ae. aegypti retained at 30 degrees C for 25 days. In the second experiment, the infection rate for Ae. aegypti that ingested a higher viral dose, and incubated at 26, 30, 32, and 35 degrees C ranged from 67% to 95%. DEN-2 virus was transmitted to monkeys only by mosquitoes maintained at greater than or equal to 30 degrees C. The extrinsic incubation period was 12 days for mosquitoes at 30 degrees C, and was reduced to 7 days for mosquitoes incubated at 32 degrees C and 35 degrees C. These results imply that temperature-induced variations in the vector efficiency of Ae. aegypti may be a significant determinant in the annual cyclic pattern of dengue hemorrhagic fever epidemics in Bangkok.

Aedes↗
PubMed1986

Correlation of survival rates of Anopheles dirus A (Diptera: Culicidae) with different infection densities of Plasmodium cynomolgi.

The survival rates are described for 36 paired replicates of Anopheles dirus A mosquitos that had been allowed to engorge themselves on rhesus monkeys that were either infected or non-infected with Plasmodium cynomolgi. The survival rates of infected mosquitos with a mean number of oocysts less than 10 did not differ significantly from those that were non-infected; however, there was a significant difference in the survival rates of non-infected groups and those with a mean number of oocysts in the range 10-40, 41-70, or >/=71.Daily survival rates for non-infected and infected mosquitos did not differ significantly during the first 8 days of extrinsic incubation. In contrast, for the period 9-30 days the survival rates of mosquitos with mean number of oocysts >/=41 were significantly different from those of non-infected mosquitos. The cumulative daily survival rates of mosquitos with mean number of oocysts up to 40, 41-70, or >/=71 decreased with the oocyst count. Mosquitos with a mean number of oocysts >/=71 frequently exhibited excessive numbers of bacteria and deterioration of both their guts and salivary glands.

Animals↗
PubMed1984

Long-term survival after bone marrow transplantation: a 15-year follow-up report of a patient with Wiskott-Aldrich syndrome.

In 1968 a 2-year-old boy with Wiskott-Aldrich syndrome was extremely ill with eczema, a series of life-threatening infections, and repeated hemorrhages into his skin, lungs, brain, and other internal organs. He was given high-dose cyclophosphamide therapy for immunosuppression, followed by bone marrow cells from his histocompatible, healthy sister. In the 15 years since bone marrow transplantation, he has had full T cell, partial B cell, and no hematopoietic engraftment. He has weathered the usual infectious diseases of childhood, has had no serious infections, and despite persistent thrombocytopenia has not had serious bleeding episodes.

B-Lymphocytes↗
PubMed1984

Cytogenetic studies of some species complexes of Anopheles in Thailand and Southeast Asia.

Recent studies on cytogenetics, behavioral, geographical and distinct morphological characters on adult, pupal and larval stages have revealed that "balabacensis" is a species complex. Anopheles dirus the mainland species, is distributed widely in Thailand and is renowned for its role as primary vector of human malarial parasites. Further, evidence from cytogenetic and taxonomic studies suggests that "An. dirus" is a species complex comprising at least four distinct species provisionally designated: dirus A, B, C and D. These cryptic species are distinguishable only partially morphologically, but can be separated on the basis of metaphase chromosomes using the Giemsa and Hoechst 33258 staining techniques. Apparently, these siblings show distinct patterns of geographic distribution in Thailand and Peninsular Malaysia. The recognition of dirus as a complex of species in Thailand and Peninsular Malaysia requires a re-evaluation of the role that the individual members of this complex have in the transmission of malaria parasites in this region. Cytological analysis of gene rearrangements in ovarian polytene chromosomes has shown that An. maculatus is a sibling-species complex consisting of at least four species in Thailand provisionally designated: maculatus A, B, C and G. These siblings are sympatric in some populations. Furthermore, species B is so highly polymorphic for chromosome rearrangements that four geographic forms can be recognized. It is not known whether these four forms are subspecies or yet further species within the species B complex. These sibling-species must be differentiated in order to understand any differential capabilities in their transmission of human malaria parasites. Anopheles nivipes was elevated from synonymy under An. philippinensis to full species status by Reid, a decision recently confirmed by cross mating experiments. The Thailand Malaria Division does not differentiate these two species and only identifies An. philippinensis, yet, An. nivipes is by far the most common of the two species in Thailand. Furthermore, preliminary surveys of the ovarian polytene chromosomes of several widely separated populations of An. nivipes in Thailand have revealed at least two distinct chromosomal types of nivipes based on fixed inversions on the X chromosomes.

Animals↗
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↗
PubMed1983

Flies as a source of enteric pathogens in a rural village in Thailand.

The village of Ban Pong in northeastern Thailand was studied from January through December 1981 to determine the importance of flies as a source of enteric pathogens. The number of flies (predominantly Musca domestica) increased in kitchens and animal pens in the hot dry spring, when the incidence of diarrhea was highest in the village. Enterotoxigenic Escherichia coli, Shigella spp., non-O1 Vibrio cholerae, and Vibrio fluvalis were isolated from fly pools in yards (69%), animal pens (38%), bathrooms (35%), and kitchens (8%). Enterotoxigenic E. coli was isolated from one fly pool in May and from another in June, when the incidence of such infections was highest in the village. Flies often carry and presumably disseminate enteric pathogens in rural Thailand.

Aeromonas↗