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Biomedical subjects

W E Collins

Publications and source records attributed to W E Collins.

At least 271 records · Page 15Linked to original sources
PubMed1979

The enzyme-linked immunosorbent assay (ELISA) for malaria. I. The use of in vitro-cultured Plasmodium falciparum as antigen.

Using the Panama II strain of Plasmodium falciparum obtained from continuous in vitro culture as antigen, the micro enzyme-linked immunosorbent assay (ELISA) was used to test serum samples from 50 persons from the southeastern United States and serum specimens collected weekly from four non-immune and nine semi-immune patients infected with P. falciparum. None of the 50 sera from the United States had ELISA antibody titers greater than 1:80. The nine semi-immune patients had rapid ELISA antibody responses (titers greater than 1:2560) following patent parasitemia. ELISA titers remained elevated despite disappearance of patent parasitemia, and declined gradually following curative antimalarial therapy. The ELISA responses observed in the four non-immune patients were more variable, though positive titers appeared rapidly with patent parasitemia. Maximum titers were lower than those observed in semi-immune patients. These results demonstrate that P. falciparum obtained from continuous in vitro culture is an excellent antigen for the micro-ELISA test for malaria. However, further assessments of the ELISA are needed to identify the conditions associated with positive responses.

Adolescent↗
PubMed1979

Plasmodium fragile and Macaca mulatta monkeys as a model system for the study of malaria vaccines.

Pladmodium fragile and the Macaca mulatta monkey are presented as a model system for the study of malarial vaccines. Four animals were immunized with culture-grown P. fragile merozoites and subsequently challenged with culture-produced parasites. One animal failed to develop a detectable parasitemia following primary challenge. Two other immunized animals had primary infections which were short-term. the parasitemias in these three monkeys following secondary challenge were short-term and the immunity was apparently sterilizing. The fourth immunized monkeys had recrudescences of the primary and secondary infection but differed markedly from the four control animals. Indirect fluorescent antibody titers increased as a result of the immunization and were indicative of the level of immunity. Because of the many similarities to the human-P. falciparum model system, the P. fragile-M. mulatta system appears to be particularly well suited for a number of malaria vaccine studies.

Animals↗
PubMed1979

Experimental Babesia microti infections in non-splenectomized Macaca mulatta.

Eight non-splenectomized Macaca mulatta were inoculated intravenously with strains of Babesia microti that originally were isolated from 2 human cases of babesiosis and then were maintained in hamsters in the laboratory. Patent infections developed in 7 animals with peak parasitemias of 496 to 3,906 organisms/mm3 blood. Prepatent periods ranged from 15 to 46 days. Parasitemia persisted for at least 90 days in all animals and in one, organisms were still present 559 days after inoculation.

Animals↗
PubMed1979

The continuous cultivation of Plasmodium fragile by the method of Trager-Jensen.

Using the Trager-Jensen method, a second malaria species, Plasmodium fragile, a simian counterpart to the human malaria P. falciparum, has been cultivated successfully. The average growth rate every 3--4 days was 5-fold and the average number of merozoites observed was 14. To date, only rhesus monkey red blood cells (RBC) would support the long-term cultivation of this parasite. Short-term observations indicate that RBC from the squirrel monkey (Saimiri sciureus) may support growth but human RBC of each of the four major AB-O types failed to support growth of the parasite. Availability of the P. fragile-rhesus monkey model would allow for a second parasite-host system for the in vitro and in vivo study of the immunologic responses of the falciparum-like parasite in a more natural host.

Animals↗
PubMed1979

Effect of sequential infection with Plasmodium vivax and P. falciparum in the Aotus trivirgatus monkey.

Aotus trivirgatus monkeys with prior experience with Plasmodium vivax were inoculated with P. falciparum via the bites of infected mosquitoes. The animals with prior malaria had higher parasitemias and significantly higher levels of mosquito infectivity than monkeys with no prior P. vivax experience. Monkeys with a history of P. falciparum that were inoculated with P. vivax had essentially the same parasitemias as those with no prior malaria. However, levels of mosquito infectivity were markedly increased in those monkeys with a history of P. falciparum. The results imply that the introduction of another malaria species into a malarious area may result in higher levels of mosquito infection and more rapid establishment and distribution of that species.

Animals↗
PubMed1979

Infection and transmission studies with Plasmodium simiovale in the Macaca mulatta monkey.

Six different anophelines--Anopheles freeborni, An. b. balabacensis, An. maculatus, An. stephensi, An. atroparvus, and An. quadrimaculatus--were shown to be susceptible to infection with Plasmodium simiovale when fed upon splenectomized Macaca mulatta monkeys between the 1st and 26th days of patent parasitemia. Transmission was obtained via the bites of An. b. balabacensis and An. maculatus mosquitoes. Prepatent periods in M. mulatta monkeys following sporozoite inoculation ranged from 11 to 20 days with a median of 14 days.

Animals↗
PubMed1979

Studies on the West African I strain of Plasmodium falciparum in Aotus trivirgatus monkeys.

The West African I strain of Plasmodium falciparum was isolated from a commercial airline pilot who had an overnight stay in Nigeria. Once established in the Aotus trivirgatus griseimembra monkey, the parasite produced high parasitemias and readily infected mosquitoes. Anopheles freeborni and An. maculatus mosquitoes transmitted the infection to additional animals. Infected salivary glands were also seen in An. culcifacies. Comparative infectivity studies indicated the most susceptible mosquito to be An. freeborni, followed by An. culicifacies, An. maculatus, and An. balabacensis balabacensis. Only 2 An. albimanus mosquitoes were infected out of 450 examined. The one A. t. trivirgatus monkey inoculated with this strain had very low levels of parasitemia.

Animals↗
PubMed1979

Infectivity of Plasmodium simium to Aotus trivirgatus monkeys and different anophelines.

Infections of Plasmodium simium were induced in splenectomized and intact Aotus trivirgatus griseimembra monkeys by parasitized blood and by sporozoites from Anopheles freeborni mosquitoes. Eleven of 13 monkeys developed infection after sporozoite inoculation; prepatent periods ranged from 11 to 25 days (mean 15.8 days). Comparative infectivity studies indicated that An, freeborni mosquitoes were the most susceptible followed by An. stephensi, An. Balabacensis balabacensis, An. maculatus, An. quadrimaculatus, An. culicifacies, and An. albimanus. Studies with 3 pupal phenotypes of An. freeborni indicated that lines containing the green and nonstriped pupal phenotypes were more susceptible than the base colony; the striped phenotype was slightly less susceptible.

Animals↗
PubMed1979

Management of primary bladder cancer by a multidisciplinary team.

Results of management of a closed series of primary bladder carcinoma over a 20-year period by a multidisciplinary team are presented. Patients were classified by the TNM method before treatment. These experiences indicate that stage and grade are relevant to prognosis and treatment. The TNM classification can be precise and practical when used diligently by a treatment team. Although no new methods of treatment are offered, the treatment now available may be utilized to better effect if programmed to allow care of the patients by a team, especially if the team explores the limits of radiation and surgery in their hands.

Adenocarcinoma↗
PubMed1978

Modification of Marshall-Marchetti-Krantz operation.

In a classic article published in 1949 Marshall, Marchetti, and Krantz demonstrated that stress incontinence in women without uterine prolapse could be corrected by a simple vesicourethral suspension. Beginning in 1960 one of the authors (W.E.C.) became concerned about suturing the urethra to the periosteum of the pubis. It occurred to him that use of the upper sutures only to pull up the bladder and hold its anterior wall to the back of the rectus muscles might be just as effective, and this has proved to be so.

Adult↗
PubMed1978

The Duffy blood group and resistance to Plasmodium vivax in Honduras.

To test the hypothesis that the Duffy blood group negative genotype is a factor in resistance to Plasmodium vivax, we determined the Duffy blood group, the malaria antibodies, and the slide-demonstrated infection rates with P. vivax and P. falciparum of 420 persons living in Nueva Armenia, Honduras. In all, 247 persons were Duffy negative. Demonstrated infections with P. falciparum were almost equally distributed between Duffy-positive (5,8%) and Duffy-negative (4.9%) persons. Similarly, Duffy-positive (25.6%) and Duffy-negative (28.2%) persons had equal proportions of indirect fluorescent antibody test titers suggestive of past or present P. falciparum infection. In contrast, all 14 P. vivax infections were found in Duffy-negative persons. There was no evidence suggesting that Duffy-positive and Duffy-negative persons had different exposures to malaria. The Duffy negative genotype FyFy appears to be a factor in resistance to P. vivax.

Antibodies↗
PubMed1978

Selection of increased quinine resistance in Plasmodium falciparum in Aotus monkeys.

Although partial resistance (RI) of Plasmodium falciparum to quinine is common in some areas of the world, failure to obtain an initial response (RII or RIII) is unusual. Furthermore, emergence of quinine resistance during therapy of malaria infections in humans and animals is uncommon. In the current study, exposure of the Panama II strain of P. falciparum in Aotus monkeys to subcurative quinine therapy during six serial passages over 6 months resulted in a shift in the quinine responsiveness of the strain from mild insensitivity to quinine to uniform resistance of a marked degree. Treatment with quinine for 14 days of infections in 12 monkeys with the original isolate resulted in cure in 8 monkeys and RI resistance in 4. Infections with the resistant isolate (selected under quinine pressure) were uniformly resistant to cure by 14 days of quinine; resistance to quinine was RIII in 4 of 12 monkeys and was RII in 5. These results suggest that extensive usage of quinine or related drugs (e.g., mefloquine) in the field may result in decreasing sensitivity of falciparum malaria to quinine.

Animals↗
PubMed1978

Disorientation training in FAA-certificated flight and ground schools: a survey.

A 10-item, voluntary questionnaire answered by 674 flight and ground schools provided information on 1) the conduct of formal instruction about disorientation, 2) the occurrence and content of lectures on disorientation, 3) use of on-the-ground demonstrations of disorientation, 4) use of in-the-air demonstrations of disorientation, 5) use of films on pilot vertigo, 6) amount of instrument flying training students receive, 7) amount of instrument flying training required of flight instructors to maintain their proficiency, 8) adequacy of the schools' programs on disorientation training, 9) other comments, and 10) numerical data regarding the number of students beginning and completing various flight and/or ground school courses. More than one-third of the respondents evaluated their disorientation training program as inadequate and defined the inadequacy most often as a lack of appropriate materials, aids, and information. Tabulations of responses to the separate items suggested areas for improvement in disorientation training. Recommendations were made.

Accidents, Aviation↗