Public health dispatch: tuberculosis outbreak in a homeless population--Portland, Maine, 2002-2003. (25/175)

During June 2002-July 2003, seven men with active pulmonary tuberculosis (TB) disease in Portland, Maine, were reported to the Maine Bureau of Health (MBH). Six were linked through residence at homeless shelters; four had matching Mycobacterium tuberculosis genotypes. Prompt investigation and identification of approximately 1,100 contacts likely prevented further spread of TB. This report summarizes preliminary results of the ongoing investigation and MBH efforts to work with health-care providers statewide to improve early detection of TB among homeless persons.  (+info)

Response in nematocyst uptake by the nudibranch Flabellina verrucosa to the presence of various predators in the Southern Gulf of Maine. (26/175)

Aeolid nudibranchs maintain nematocysts sequestered from their cnidarian prey for protection against predators. Selection for nematocyst incorporation is a function of diet and prey choice, but ratios vary among nudibranchs feeding on a given diet, indicating that other factors may be involved. It is proposed that the presence of predators influences nematocyst incorporation. Nematocyst uptake in the nudibranch Flabellina verrucosa collected from the southern Gulf of Maine was examined in response to various potential predators, including Crossaster papposus, Tautogolabrus adspersus, and Carcinus maenas. Nudibranchs in individual flow-through containers feeding on a diet of the hydroids Tubularia spp. and Obelia geniculata were subjected to tanks containing a predator, then their nematocyst distribution was examined. Although most of the changes over the experimental period were attributable to diet, F. verrucosa responded to both T. adspersus and C. papposus by significantly increasing microbasic mastigophore incorporation. No differential uptake was seen with C. maenas. Response was evident in the nudibranchs both for predators present in the collection area and for those with which they had no previous exposure, indicating that F. verrucosa modulates nematocyst incorporation in response to the presence of predators as well as to diet. A coevolution of nudibranchs and potential predators may govern changes in nematocyst uptake.  (+info)

Snowmobile fatalities--Maine, New Hampshire, and Vermont, 2002-2003. (27/175)

During the 2002-2003 winter season in northern New England, 28 deaths in three states were associated with the use of snowmobiles, more than reported during any of the previous 12 winter seasons. The New Hampshire Department of Health and Human Services conducted a study to characterize these fatal injuries. This report describes the results of that study, which indicated that the leading contributors to snowmobile fatalities were excessive speed, inattentive or careless operation, and inexperience. Efforts to reduce snowmobile fatalities should focus on improving safety measures, including establishing speed limits, strengthening enforcement of snowmobile operating rules, and promoting safety education.  (+info)

Laser scanning cytometry and tissue microarray analysis of salinity effects on killifish chloride cells. (28/175)

The effects of salinity on chloride cells (CC) and Na(+)/K(+)-ATPase content in gill epithelium of euryhaline killifish Fundulus heteroclitus were analyzed using laser scanning cytometry (LSC) and tissue microarrays (TMAs). Salinity acclimations consisted of acute transfer from freshwater (FW) to 1x seawater (SW) and gradual transfer from FW to 2.4x SW. Suspensions of dissociated gill epithelial cells were stained with DASPMI and evaluated using LSC. CC number and volume are proportional to external salinity, being lower in FW (0.5+/-0.2 x 10(5) and 405+/-32 micro m(3), respectively) and higher after 5 weeks in 2.4x SW (3.7+/-0.9 x 10(5) and 2697+/-146 micro m(3), respectively). TMAs were constructed from fixed gill tissues and developed using antibody for Na(+)/K(+)-ATPase to visualize CCs in situ and compare their characteristics with isolated CCs. Na(+)/K(+)-ATPase content per CC increases transiently (from 2.2+/-0.5 x 10(6) to 4.8+/-1.1 x 10(6) relative fluorescence units, RFU) after 1 week of acute acclimation to 1x SW but returns to baseline values (2.4+/-0.5 x 10(6) RFU) within 5 weeks. In contrast, gradual acclimation to 2.4x SW permanently increases Na(+)/K(+)-ATPase content per CC (from 2.0+/-0.8 x 10(6) to 6.7+/-2.7 x 10(6) RFU after 5 weeks). CC size in situ did not correlate well to salinity because of basolateral membrane infoldings. Taken together, these data suggest that euryhaline fishes are capable of sensing environmental salinity to utilize transient short-term and permanent long-term adaptations for coping with salinity changes. These results also demonstrate the power of LSC and TMA for comparative biology.  (+info)

Progress toward paperless radiology in the digital environment: planning, implementation, and benefits. (29/175)

A growing number of hospitals have installed PACS (Picture Archiving and Communications Systems) in order to improve patient care and to facilitate improved efficiencies. While eliminating films is commonly one of the first goals in planning a successful PACS implementation, eliminating the manual handling of paperwork can also produce a substantial benefit. We describe the process utilized at Maine Medical Center (MMC) to achieve a substantial degree of freedom from paperwork. Some of the benefits were expected, but some unexpected benefits also revealed themselves during this process.  (+info)

Identification and activity-dependent labeling of peripheral sensory structures on a spionid polychaete. (30/175)

In marine sedimentary habitats, chemoreception is thought to coordinate feeding in many deposit-feeding invertebrates such as polychaetes, snails, and clams. Relatively little is known, however, about the chemosensory structures and mechanism of signal transduction in deposit feeders. Using electron microscopy, confocal laser scanning microscopy (CLSM), and immunohistochemistry, we investigated the structure and function of putative chemosensory cells on the feeding appendages of a deposit-feeding polychaete species, Dipolydora quadrilobata. Tufts of putative sensory cilia were distributed over the prostomium and feeding palps and typically occurred next to pores. Examination of these regions with transmission electron microscopy revealed multiciliated cells with adjacent glandular cells beneath the pores. The sensory cells of prostomium and palps were similar, displaying an abundance of apical mitochondria and relatively short ciliary rootlets. Staining with antiserum against acetylated alpha-tubulin was examined by CLSM, and revealed axonal processes from putative sensory tufts on the palp surface to palp nerves, as well as many free nerve endings. Activity-dependent cell labeling experiments were used to test the sensitivity of putative sensory cells on the palps to an amino acid mixture that elicited feeding in previous behavioral experiments. In static exposures, the number of lateral and abfrontal cells labeled in response to the amino acid mixture was significantly greater than in the controls. Ultrastructural, positional, and now physiological evidence strongly suggests that spionid feeding palps are equipped with sensory cells, at least some of which function as chemoreceptors.  (+info)

Adaptable defense: a nudibranch mucus inhibits nematocyst discharge and changes with prey type. (31/175)

Nudibranchs that feed on cnidarians must defend themselves from the prey's nematocysts or risk their own injury or death. While a nudibranch's mucus has been thought to protect the animal from nematocyst discharge, an inhibition of discharge by nudibranch mucus has never been shown. The current study investigated whether mucus from the aeolid nudibranch Aeolidia papillosa would inhibit nematocyst discharge from four species of sea anemone prey. Sea anemone tentacles were contacted with mucus-coated gelatin probes, and nematocyst discharge was quantified and compared with control probes of gelatin only. Mucus from A. papillosa inhibited the discharge of nematocysts from sea anemone tentacles. This inhibition was specifically limited to the anemone species on which the nudibranch had been feeding. When the prey species was changed, the mucus changed within 2 weeks to inhibit the nematocyst discharge of the new prey species. The nudibranchs apparently produce the inhibitory mucus rather than simply becoming coated in anemone mucus during feeding. Because of the intimate association between most aeolid nudibranchs and their prey, an adaptable mucus protection could have a significant impact on the behavior, distribution, and life history of the nudibranchs.  (+info)

Fertilization in an egg-brooding colonial ascidian does not vary with population density. (32/175)

The possibility that free-spawning marine organisms may be subject to fertilization failure at low population density (due to the effects of sperm dilution) has sparked much interest, but these effects have been demonstrated only in a few species that broadcast their eggs. Some egg-brooding species may overcome dilution effects by filtering low concentrations of sperm from seawater and fertilizing eggs throughout an extended period of time. We examined the effects of population density and size on fertilization in Botryllus schlosseri, a hermaphroditic colonial ascidian that free-spawns sperm, but broods eggs. We experimentally manipulated the size and density of mating groups and surveyed fertilization levels in natural populations that varied in density. Fertilization was not affected by variation in population size or density in either the experimental or natural populations. Near the end of the reproductive season, some eggs may have been fertilized too late to complete development, suggesting a temporal form of sperm limitation that has not been considered in other systems. We also detected greater variability in fertilization levels at lower population density. Nevertheless, these results suggest that caution must be used in extrapolating reported density effects on fertilization to all taxa of free-spawners; density effects may be reduced in brooders that have efficient sperm collection mechanisms.  (+info)