Risk-stratification, resource availability, and choice of surgical location for the management of parturients with abnormal placentation: a survey of United States-based obstetric anesthesiologists.

BACKGROUND: Parturients with abnormally adherent placentas present anesthetic challenges that include risk-stratification, management planning and resource utilization. The labor and delivery unit may be remote from the main operating room services. METHODS: Division chiefs of North American obstetric anesthesiology services were surveyed about their practices and management of parturients with an abnormally adherent placenta. RESULTS: Eighty-four of 122 chiefs, representing 103 hospital sites, responded to the survey (response rate 69%). Sixty-one percent of respondents agreed that women with preoperative placental imaging that was "suspicious" of placenta accreta represented a lower risk category; all other suggested descriptions fell into a higher risk category. Seventy-nine percent of respondents indicated that lower risk cases were managed on the labor and delivery unit, while 71% indicated that higher risk cases would be managed in the main operating room. Institutions where all cases were managed on the labor and delivery unit had better access to human and technical resources, were less remote from their main operating areas, and promoted neuraxial rather than general anesthesia, even for parturients perceived to be at higher risk. CONCLUSIONS: Obstetric anesthesia leaders identified patients at lower clinical risk and those less likely to require greater resources. Additional resources were available in institutions where all abnormal placentation cases were managed on the labor and delivery unit. Practitioners should consider risk-stratification and resource availability when planning high-risk cases.

Serological responses against the pathogenic dimorphic fungus Mucor amphibiorum in populations of platypus (Ornithorhynchus anatinus) with and without ulcerative mycotic dermatitis.

Mucor amphibiorum, a dimorphic fungus, causes ulcerative dermatitis and systemic infections in the platypus Ornithorhynchus anatinus in some river systems in Tasmania but apparently not in other regions of Australia. As yet there are no suitable tests for population surveys, nor for detection of internal lesions in live animals. Consequently, immunoglobulins were purified from the serum of platypuses and anti-immunoglobulin antisera were prepared in rabbits in order to develop an enzyme-linked immunosorbent assay (ELISA) for anti-M. amphibiorum antibodies. Antigens from plate-grown cultures resulted in greater signal-to-noise ratios in indirect ELISA than those from broth-grown cultures. Platypuses with clinical ulcerative dermatitis had elevated anti-Mucor antibody levels compared to apparently unaffected individuals. Seroconversion was observed in one animal coincident with the development of cutaneous ulcers. The results suggested that platypuses in affected rivers were exposed to M. amphibiorum at a higher frequency than the occurrence of clinical disease. Some platypuses from New South Wales had elevated antibody levels but these increased significantly with age suggesting exposure to cross-reactive antigens, although exposure to M. amphibiorum cannot be excluded. Further studies are warranted to determine factors that result in progression from infection to disease, the occurrence of the fungus in areas where disease has not been observed and the specificity of antigen used in ELISA.

Distinct physical and structural properties of the ovine uterine serpin.

Experiments were performed to examine the relationship between the structure and function of ovine uterine serpin (OvUS). Limited proteolytic digestion of OvUS caused cleavage of the 55-57 kDa OvUS to a 42 kDa product nearly identical in molecular weight to a naturally-occurring breakdown product of OvUS. N-terminal amino acid sequencing and MALDI-MS revealed that, unlike other serpins, OvUS was preferentially cleaved at about 70 amino acids upstream of the putative reactive center loop. Analysis of the partially-digested protein by gel filtration chromatography suggested that the C-terminal fragment of the protein was still associated under nondenaturing conditions. Partial digestion of OvUS had no effect on the protein's secondary structure, thermal stability, ability to bind lymphocytes or pepsin, or inhibitory activity towards pepsin or mitogen-induced lymphocyte proliferation. In contrast, mild denaturation of OvUS with 0.5 M guanidine HCl increased thermal stability. Unlike for other serpins, the increase in thermal stability was lost upon removal of the denaturant. Incubation of OvUS with 100 fold molar excess of a peptide corresponding to the putative P(14)-P(2) region of the RCL for 24 h at 37 degrees C to induce binary complex formation had no effect on its secondary structure and did not alter the biological activity of the protein. Synthetic peptides corresponding to the putative P(14)-P(2) region and the P(7)-P(15') region of the RCL were not inhibitory to pepsin activity or lymphocyte proliferation. Taken together, these results indicate that the conformation of OvUS is distinct from the prototypical serpin because conditions that lead to the large-scale conformational change in other serpins such as antithrombin III and alpha(1)-antitrypsin do not cause similar changes in OvUS. Moreover, the putative RCL does not seem to contain the activity required to inhibit lymphocyte proliferation or pepsin activity.

Structures of yeast vesicle trafficking proteins.

In protein transport between organelles, interactions of v- and t-SNARE proteins are required for fusion of protein-containing vesicles with appropriate target compartments. Mammalian SNARE proteins have been observed to interact with NSF and SNAP, and yeast SNAREs with yeast homologues of NSF and SNAP proteins. This observation led to the hypothesis that, despite low sequence homology, SNARE proteins are structurally similar among eukaryotes. SNARE proteins can be classified into two groups depending on whether they interact with SNARE binding partners via conserved glutamine (Q-SNAREs) or arginine (R-SNAREs). Much of the published structural data available is for SNAREs involved in exocytosis (either in yeast or synaptic vesicles). This paper describes circular dichroism, Fourier transform infrared spectroscopy, and dynamic light scattering data for a set of yeast v- and t-SNARE proteins, Vti1p and Pep12p, that are Q-SNAREs involved in intracellular trafficking. Our results suggest that the secondary structure of Vti1p is highly alpha-helical and that Vti1p forms multimers under a variety of solution conditions. In these respects, Vti1p appears to be distinct from R-SNARE proteins characterized previously. The alpha-helicity of Vti1p is similar to that of Q-SNARE proteins characterized previously. Pep12p, a Q-SNARE, is highly alpha-helical. It is distinct from other Q-SNAREs in that it forms dimers under many of the solution conditions tested in our experiments. The results presented in this paper are among the first to suggest heterogeneity in the functioning of SNARE complexes.

Field biology of the platypus (Ornithorhynchus anatinus): historical and current perspectives.

The field biology of the platypus, Ornithorhynchus anatinus, was first studied by a number of expatriate biologists who visited the Australian colonies to collect specimens in the 1800s. Their work was followed in the early to mid-1900s by a group of resident natural historians and later by an increasing number of academic biologists. All of these workers contributed significantly to the current understanding of the field biology of this unique Australian species. The platypus occupies much the same general distribution as it did prior to European occupation of Australia, except for its loss from the state of South Australia. However, local changes and fragmentation of distribution due to human modification of its habitat are documented. The species currently inhabits eastern Australia from around Cooktown in the north to Tasmania in the south. Although not found in the west-flowing rivers of northern Queensland, it inhabits the upper reaches of rivers flowing to the west and north of the dividing ranges in the south of the state and in New South Wales and Victoria. Its current and historical abundance, however, is less well known and it has probably declined in numbers, although still being considered as common over most of its current range. The species was extensively hunted for its fur until around this turn of this century. The platypus is mostly nocturnal in its foraging activities, being predominantly an opportunistic carnivore of benthic invertebrates. The species is homeothermic, maintaining its low body temperature (32 degrees C), even while foraging for hours in water below 5 degrees C. Its major habitat requirements include both riverine and riparian features which maintain a supply of benthic prey species and consolidated banks into which resting and nesting burrows can be excavated. The species exhibits a single breeding season, with mating occurring in late winter or spring and young first emerging into the water after 3-4 months of nurture by the lactating females in the nesting burrows. Natural history observations, mark and recapture studies and preliminary investigations of population genetics indicate the possibility of resident and transient members of populations and suggest a polygynous mating system. Recent field studies have largely confirmed and extended the work of the early biologists and natural historians.

Comparing adjustment to an ostomy for three groups.

Three groups of persons with fecal ostomies (those with permanent ostomies as a result of disease (n = 13), those with temporary ostomies as a result of disease (n = 16), and those with temporary ostomies as a result of trauma (n = 18) were interviewed with various instruments to explore the psychosocial impact of an ostomy. The three groups did not differ significantly with respect to their scores on the Psychosocial Adjustment to Illness Scale, the Reintegration to Normal Living Index, or the Meaning in Life Scale. Those with a temporary ostomy as result of trauma had significantly higher Escape-Avoidance, Positive Reappraisal, Accepting Responsibility, and Planful Problem Solving subscores on the Ways of Coping instrument. The differences in coping scores may relate to adjustment to the violent act at the same time as the ostomy. These observations add to ostomy research because research about persons with temporary ostomies, especially those caused by a gunshot injury, is scarce.

Hematological changes in the platypus (Ornithorhynchus anatinus) following capture.

Blood samples were collected from the bill sinus of nine free-living platypuses (Ornithorhynehus anatinus) within 12 min of capture of each and again after 1 to 12 hr, New South Wales, Australia, 1981 to 1988. In seven animals which were not anesthetized, there was a significant (P < 0.01) fall in lymphocyte count between the two samples. The reduction ranged from 10 to 58% of the initial lymphocyte count and caused a significant reduction in the total white cell count (P < 0.05). Both the neutrophil and the lymphocyte counts increased in two platypuses which were anesthetized with ether prior to collection of the second blood sample. We propose that the peripheral blood lymphocyte count is a simple means of monitoring the stress response of non-anesthetized, newly-captured platypuses and may be a useful adjunct to behavioral observation.

Transference of marine fouling communities between polluted and unpolluted sites: Impact on structure.

Fouling communities were transferred between Wollongong Harbour (Australia), a relatively unpolluted area, and nearby Port Kembla Harbour which is affected by pollution from nearby heavy industries. Those that had been transferred from Wollongong Harbour were similar in structure after two months to those that had developed entirely in Port Kembla Harbour. Conversely, the communities transferred from Port Kembla Harbour had a similar structure to those that had developed only in Wollongong Harbour. Many of the species transferred from Wollongong Harbour were thought to have been killed by periodic high concentrations of pollutants or overgrown by more competitive species. Those few that survived the polluted conditions were mainly bryozoans and serpulids. Surprisingly, many supposedly pollution-tolerant species transferred from Port Kembla Harbour did not survive in Wollongong Harbour. It is suggested that this was because these animals could not tolerate the lower nutrient conditions in the latter area. Space once occupied by these species was quickly colonised by species found only in Wollongong Harbour. These results have important implications for the functioning of these communities.

Fatty acids of the milk and food of the platypus (Ornithorhynchus anatinus).

Platypus milk fat contains 98.5% triglyceride. Polyunsaturates (C18∶2-C22∶5) account for 29% of the triglyceride fatty acids in the milk fat and 32% of the total fatty acids in the lipid of the food of the platypus. Linoleate and arachidonate are the major ω6 polyunsaturates of both food and milk lipids. However, while the ω3 polyunsaturates linolenate and eicosapentaenoate are present in both food and milk, docosapentaenoate is present in meaningful amounts in milk only. It is suggested that with the exception of 22∶5ω3, the polyunsaturates in platypus milk originate in the diet.

Thyroid hormone levels in an egg-laying mammal, the platypus Ornithorhynchus anatinus.

Serum thyroxine (T4) and triiodothyronine (T3) levels were measured in wild-caught platypuses in southeastern Australia in summer (February) and late winter (September). There was little seasonal difference in thyroid hormone levels. Males had lower levels of both T4 and T3 than did females, but this was only statistically significant for T3. Juveniles had higher levels than adults. The levels of thyroxine ranged from 37 to 136 nmol . liter-1, and triiodothyronine from 0.3 to 1.7 nmol . liter-1. These thyroxine levels are much higher than found in marsupials or the other egg-laying mammal, the echidma, and it is suggested that they may be associated with the platypus' relatively high metabolism and growth rate.