3H]prostaglandin uptake in vivo by rabbit uterine tissues and blastocysts

Day-6 pregnant rabbits were anesthetized and subjected to a mid-ventral laparotomy. [3H] Prostaglandin F2alpha) (PGF2alpha) [3H]PGE2, [14C]Urea or [14C]Sucrose were instilled into the uterine lumen via the uterotubal junction. The amounts instilled/uterine horn were respectively 3.7 +/- 0.3, 3.5 +/- 0.3, 5.7 +/- 1.3 and 2.7 +/- 1.6 muCi in 20mul of buffer. Animals were killed at 1, 2, 9, 19 or 21 h after radioactive instillation, and the amounts of radioactivity in blastocysts, uterine tissue, peritoneal cavity washings and urine evaluated by liquid scintillation spectrometry. A gradient of radioactivity was observed from the uterotubal junction to the cervical end of the uterus. Large amounts of [3H]PG were found in the injected horn and associated blastocysts with a considerable crossover to the non-injected horn, but little in the associated blastocysts. Much of the blastocysts associated- [3H]PG remained unmetabolized. Large amounts of metabolized [3 H] were found in urine. [14C]Urea was taken up by uterine tissue in the injected horn, but there was little cross over to the non-injected horn. Urea was also found in urine. Much of the [14C]Sucrose remained in the injected horn, and little was recovered from the urine. It was found that at 9 h, but not at 19 h, after [3 H]PG instillation, the PG was localized at the site of the blastocysts in the injected but not in the contralateral horn. Significantly more [3H]PGF2alpha than [3H]PGE2 was localized in this situation. [14C]Urea was not localized at the site of the blastocysts in urea injected horns. (ABSTRACT TRUNCATED AT 250 WORDS)     

A new species of land planarian preying on termites in Kenya (Platyhelminthes: Turbellaria: Tricladida: Terricola)

A new species of land planarian is described from Kenya. Microplana rermirophaga sp. nov. preys on termites by capturing them at the openings to their nest. The pharynx is unusually far forwards for a land planarian and this is probably related to the active nature of the prey. There is an anterior depression caused by the termination of parenchymal longitudinal muscle bundles which might act as a sucker. All specimens are immature which leads to some difficulty in assigning the species to a genus.     

Caseload or workload? Scoring complexity of operative procedures as a means of analysing workload.

OBJECTIVE--To present a more realistic assessment of surgical workload than that provided by a case count. DESIGN--Prospective study of all the operative procedures performed in one year, classified according to the British United Provident Association''s schedule of procedures and scored by the "intermediate equivalent" value (taking the recommended fee value of an intermediate operation as 1.0) compared with the number of operations performed. SETTING--General surgical unit of Taunton and Somerset Hospital, comparing four consultant surgeons and their teams. PATIENTS--Inpatients and day patients admitted under the care of general surgeons during 1989. MAIN OUTCOME MEASURE--Difference between the apparent workload represented by simple case counting (caseload) and the actual workload represented by calculation of the total "intermediate equivalent" value. RESULTS--The workload assessed in terms of intermediate equivalent values was greater than that suggested by case counting for complex operations (12% v 4%), operations at the district hospital (82% v 74%), and operations performed by consultants (53% v 35%) and was lower for minor operations (20% v 42%), operations at the community hospitals (18% v 26%), and operations performed by surgeons in training grades and clinical assistants (47% v 66%). CONCLUSIONS--The use of the intermediate equivalent values as an indicator of complexity allows a more realistic assessment of the operative workload than a simple case count of the number of different operations and is recommended for comparing workload in different hospitals and departments.     

Synchrony of bone marrow proliferation and maturation as the origin of cyclic haemopoiesis

Abstract. Cyclic haemopoiesis in Grey Collie dogs is characterized by stable oscillations in all haemopoietic lineages. It is proposed that in these animals, in contrast to normal animals, the maturation process of haemopoietic (in particular granuloid) cells from the primitive progenitors to the functional cells is characterized by an abnormally strong synchrony. It is conjectured that the marrow maturation time has a very small variance compared with non-cyclic normal dogs. With a mathematical model of haemopoiesis it is shown that small fluctuations are amplified via regular feedback processes such that stable granuloid oscillations are established. Erythroid oscillations are induced indirectly by granuloid feedback to the stem cell pool. The model calculations further show that the synchrony hypothesis of bone marrow maturation can quantitatively explain the following experimental results: (1) the maintenance of stable cycles of granuloid and erythroid bone marrow and blood cells with a period of approximately 14 d; (2) the disappearance of granuloid and erythroid cycles during the administration of the colony stimulating factor rhG-CSF; (3) the reappearance of oscillations when the administration of CSF is discontinued; (4) the cessation of cycles during endotoxin application; and (5) the persistence of cycles during erythroid manipulations (bleeding anaemia, hypoxia, hypertransfusion). We therefore conclude that cyclic haemopoiesis is not caused by a defect in the regulatory control system but by an unusual maturation process.     

Distribution of Nephrops norvegicus (L.) larvae in the western Irish Sea: an example of advective control on recruitment

Results of a survey of Nephrops norvegicus larvae conductedin the western Irish Sea during May 1984 are discussed. Thelarval distributions show a pronounced tongue of high numbersextending southward from the muddy area where they are hatched.The inferred density-driven circulation at the time of the surveyis consistent with the southward transport of larvae. BecauseN.norvegicus requires a muddy substrate for successful larvalsettlement, the processes which influence the circulation mayprovide an important control on the level of recruitment.