Role of mate's previous experience in ring dove hormone-induced incubation

Progesterone-induced incubation was examined in 40 pairs of adult ring doves, differing in their previous reproductive experience (courtship vs. nest building) and the previous reproductive experience of their mates (courtship vs. nest building) during testing. Only the previous experience of the experimental subject significantly affected the establishment of incubation during the 24-hr test period. More doves experienced with nest building established incubation than did courtship-experienced doves. The latency to enter the nest area and the latency to stand on the nest were affected by both the previous breeding experience of the subject and the previous breeding experience of its mate. Nest-building-experienced mates decreased the latencies of courtship-experienced subjects, and courtship-experienced mates increased the latencies of nest-building-experienced doves. Males were not more affected by their mates' experience than were females. Time spent on the nest was affected only by the subject's previous experience and sex. While the hypothesis that the behavior of the mate can affect a dove's progesterone-induced incubation was not confirmed, the mate's behavior can affect some of the components of nest responsiveness.     

Nosocomial pseudobacteremia. Positive blood cultures due to contaminated benzalkonium antiseptic

Pseudomonas cepacia or Enterobacter species or both were isolated from blood cultures of 79 patients in a community hospital between April 1971 and March 1972. No common exposures other than venipuncture correlated with positive blood cultures. Pseudomonas cepacia, Enterobacter, and other Gram-negative enteric bacteria were cultured from aqueous benzalkonium chloride used for skin antisepsis prior to ordinary and blood culture venipuncture. Contamination of blood cultures by organisms from the antiseptic most likely accounted for positive cultures in 35 to 38 patients (92%) with P cepacia. The remaining three patients had repeated blood cultures positive for P cepacia and circumstantial clinical evidence of bacteremia; they may have contracted disease through exposure to the contaminated antiseptic. Substitution of an iodine-alcohol antiseptic abruptly reduced the isolation of P cepacia and Enterobacter.     

The synaptic organization of the cerebello-olivary circuit

Section of the superior cerebellar peduncle just rostral to the deep cerebellar nuclei results in degenerating axon terminals within the contralateral inferior olive. The nuclear origin of this fiber system and its distribution within the subdivisions of the inferior olive were described in a companion study (Martin et al., 1976). Precise localization of these degenerating terminals within the nucleus was accomplished by the examination of 1 mu plastic sections cut from each tissue block prior to thin sectioning. Degenerating axon terminals are present in all the nuclear subdivisions and when seen with the electron microscope they frequently are localized in the previously described synaptic clusters (King, 1976). These terminals demonstrate an electron dense reaction at survival times of 2 and 3 days. By day 4, they are shrunken and irregular in shape, and typically are surrounded by astrocyte processes. Cerebello-olivary axon terminals measure 1-3 mu, contain spherical, clear synaptic vesicles and typically contact spiny appendages within the synaptic clusters (glomeruli). Thus, we have demonstrated that one of the primary axon systems which terminates within the synaptic clusters is from the cerebellar nuclei. We have yet to determine the origins of the remaining terminals within the synaptic clusters which include endings with either smaller spherical, pleomorphic or numerous dense core vesicles.     

Clinical considerations on retroperitoneal liposarcoma. Report of 2 cases

Liposarcoma is one of the more common tumours of the soft retroperitoneal tissues. It usually occurs in aged subjects and displays a marked contrast between its malignant histological picture and its protracted, poorly symptomatic clinical picture. Eventually, compression or invasion of nearby organs appears, whereas the patient's general condition is not affected. Two personal cases are described.     

Rechargeable silver-modified mercuric oxide-zinc cell for cardiac pacemakers

Tests were conducted on rechargeable mercury-zinc pacemaker batteries under simulated and actual biologic conditions, using a variety of discharge rates and charging schedules. In tests on 96 cells at a 6.4 milliampere (ma) discharge, recharging once every 15 months of simulated pacing at a 25 microampere (mua) drain, the earliest cell failure occurred after an equivalent of 50 years of pacing. The mean pacing equivalent for all 96 cells was more than 140 years. In 6.4 ma discharge tests on 24 cells, recharging once every 8 days of simulated pacing, only 1 cell in 24 failed after an equivalent of more than 500 years of pacing (actual time 2 years). In tests on 13 cells pacing at a 200 mua drain without recharging, the simulated mean duration of pacing before total discharge was 4.8 years. Seven other cells at a 200 mua drain with periodic recharging continue to function normally after more than 7 years of actual time, simulating 56 years of pacing at a 25 mua drain. Cardiac pacemakers using the rechargeable mercury-zinc cell have been implanted in animals for more than 2 1/2 years and in patients for more than 1 year with all units continuing to function satisfactorily. It has been demonstrated unequivocally that a rechargeable mercury-zinc pacemaker will function continuously for more than 4 years without recharging and that periodic recharging will extend pacing life far beyond that predicted for lithium and nuclear primary power sources.