Search PubMed⌕ Search

Biomedical subjects

C M Herman

Publications and source records attributed to C M Herman.

At least 55 records · Page 3Linked to original sources

Blood parasites of some birds from Kenya, Tanzania and Zaire.

A total of 647 birds of 146 species representing 41 families from localities in Kenya, Tanzania and Zaire were examined for blood parasites. A total of 242 (37.2%) birds harbored either single or multiple infections of Haemoproteus (16%), Leucocytozoon (14%), Plasmodium (5.4%), Trypanosoma (1.7%), microfilaria (2.9%) or a variety of babesioids and haemogregarines (4.3%). Occurrence of blood parasites was greatest in Zaire and least in Kenya; the occurrence of the different genera varied markedly between areas and between bird families.

Animals↗

Twenty-four hour membrane oxygenation in dogs without anticoagulation.

Is systemic heparinization or heparin-bonded circuitry better than no anticoagulation during 24 hours of cardiopulmonary bypass? We compared blood pressure, coagulation state, oxygenator function, and scanning electron microscopic appearance of the circuits. There were three groups of five dogs each: Group I had no anticoagulants; Group II received systemic heparization; Group III perfusions utilized heparin-bonded circuits. Group I animals all survived, whereas 80 percent (four fifths) in Group II and 20 percent (one fifth) in Group III survived. Arterial pressures were better maintained in Group I as compared to Groups II and III. The coagulation parameters were similar in all groups. Oxygenator function was maintained at normal in all groups. No thrombi were present in any of the circuits following perfusion. The surfaces in Group I had less debris on them compared to Groups II and III. Animals that died had fibrin thrombi present in tissues examined histologically. Systemic heparinization had no advantage over no heparin in this study. The striking similarity of the coagulation state between Groups I and II and better preservation of the surfaces in Group I were unexpected. Heparin-bonded circuits were unsatisfactory when compared to no anticoagulation and systemic heparinization. Additional experiments with various species with and without anticoagulation must be done to determine the best guidlines for human cardiopulmonary bypass.

Animals↗

Remarks on the status of the genus Leucocytozoon Sambon, 1908.

Authorship of the genus Leucocytozoon has been variously assigned to several investigatiors, especially Danilewsky and Ziemann. Recently Hsu, Campbell & Levine (1973) have credited it to Berestneff. It is herein submitted that they erred in doing so and in relegating Akiba Bennett, Garnham & Fallis, 1965 and Saurocytozoon Lainson & Shaw, 1969 to synonymy with it. An attempt is made to clarify the confusion that has increasingly surrounded the genus Leucocytozoon, and it is recommended that the type species (by designation) should be Leucocytozoon majoris (Laveran, 1902), one of a mixture of organisms earlier lumped together under a name (Haemamoeba Grassi & Feletti, 1890) currently reserved for an avian subgenus of Plasmodium Marchiafava & Celli, 1885. We conclude that the generic name should be credited to Sambon, the 1st author to present an unequivocal description of the genus.

Animals↗

Leucocytozoonosis in Canada geese at the Seney National Wildlife Refuge.

A history is given of the Seney National Wildlife Refuge and the losses of goslings of Canada geese (Branta canadensis) recorded since inception of the refuge in 1935. Since 1960, when more reliable data became available, losses have been estensive every 4 years. Goslings deaths are attributed to the infection with Leucocytozoon simondi. The blackfly (Simulium innocens) is considered to be the prime vector in the transmission of this blood parasite to goslings.

Animals↗

The relationship of circulating endogenous endotoxin to hemorrhagic shock in the baboon.

Experiments were carried out to test the hypothesis that during hemorrhagic shock endotoxin enters the circulation from ischemic bowel by way of the portal venous system and is then associated with irreversibility of the hemorrhagic shock state. After placement of sampling catheters in the portal vein, right atrium, and aorta, 14 awake, restrained baboons were subjected to 1 hour of hemorrhagic shock at a mean arterial pressure (MAP) of 60 torr followed by a second hour at 40 torr MAP. Six animals were resuscitated with Ringers lactate and their shed blood; 8 were maintained hypotensive until death. Serial blood samples were analyzed for the presence of endotoxin. Endotoxemia was found infrequently, with no greater incidence (p > 0.6) in portal venous samples than in systemic blood, so these data were pooled for further analysis. Furthermore, endotoxemia was no more frequent (p > 0.6) late in shock than it was in early shock or during the baseline period. Autopsy showed no evidence of ischemic damage to the splanchnic viscera. It was concluded that spontaneous endogenous entotoxemia is not a common feature of hemorrhagic shock in baboons and is not related to the duration or degree of severity of hemorrhagic shock in this subhuman primate species.

Animals↗