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Selected AbstractsThe use of near infrared interactance in hemodialysisHEMODIALYSIS INTERNATIONAL, Issue 1 2005N. Sarhill Forty-one consecutive admissions to a hemodialysis center were evaluated. Demographic information including age, gender, race, and diagnosis was collected. Patients, >18 years old, with end stage renal disease and on hemodialysis for at least one year were included. Those with edema or known ascites were excluded. Weight was measured before and after hemodialysis (HD) using a standard scale and by considering the amount of fluid loss by the hemodialysis machine. Body composition including total body water (TBW) was calculated before and after HD using near infrared interactance (NIR). All measurements were completed during half hour before and after HD. Forty-one patients included: men (n = 26), women (n = 15); median age 58 (range 28,88 years). Twenty-eight were African American and the rest Caucasians. The amount of intravascular fluid taken after HD (assessed by weight reduction) ranged 0,5 L with median 2.2 L. NIR analysis for the same patients at the same time showed different total body water measurements in 91% of cases (P > 0.05). Moreover, NIR analysis showed increase in total body water in 24% of patients even though the hemodialysis machine showed a loss of total body water; median of 1.3 (range: 0,3L). The error in measuring body composition with NIR was both large and varied (random and not systematic error). We conclude that NIR analysis cannot be considered as a reliable method to evaluate body composition, especially total body water, amongst patients with end stage renal disease undergoing hemodialysis. [source] ARE SPERM LIMITING IN THE SEA?JOURNAL OF PHYCOLOGY, Issue 2000M. L. Berndt The reproductive success of marine species with external fertilization depends on environmental conditions during gamete release. There is special interest presently in whether water motion causes sperm limitation under natural conditions. We investigated gamete release of Fucus vesiculosus from an exposed shore to ascertain: 1) when gametes are released during the tidal cycle, 2) when fertilization occurs, and 3) what the natural sperm:egg ratios are. Water samples were collected and concentrated over five minutes every half hour off Pemaquid Point, ME from three replicate sites within each of two locations using a pump-filter device. Immunofluorescence microscopy revealed that gamete release occurred only on the two calmest spring tides. Sperm became present in the water column at the same time as oogonia (30 min,1 h prior to high tide [HT]) and reached peak concentration at exactly HT. The sperm:egg ratio was 76:1 on 8 Oct 1999 and 21:1 on 8 Nov 1999 at exactly 30 min prior to HT and dropped sharply after HT. Gametes continued to be collected for several hours after HT but analysis of pronuclear position in aceto-iron-hematoxylin stained eggs revealed that all fertilization occurred at approximately HT. We modelled the total number of days when reproduction was possible using these results and wind and wave data from the National Data Buoy Center. Our research provides evidence that gamete release by F. vesiculosus occurs at slack HT on calm days and that sperm are not a limiting factor in fertilization for this species. [source] The sodium tail of MercuryMETEORITICS & PLANETARY SCIENCE, Issue 9 2002A. E. POTTER However, when the angle of the ecliptic is near maximum in the northern hemisphere, and Mercury is near its greatest eastern elongation, it can be seen against the western sky for about a half hour after sunset. During these times, we were able to map sodium D2 emission streaming from the planet, forming a long comet-like tail. On 2001 May 26 (U.T.) we mapped the tail downstream to a distance of ,40 000 km. Sodium velocities in the tail increased to ,11 km s,1 at 40 000 km as the result of radiation pressure acceleration. On 2000 June 5 (U.T.) we mapped the cross-sectional extent of the tail at a distance of ,17 500 km downstream. At this distance, the half-power full-width of the emission was ,20 000 km. We estimated the transverse velocity of sodium in the tail to range from 2 to 4 km s,1. The velocities we observed imply source velocities from the planet surface of the order of 5 km s,1, or 4 eV. Particle sputtering is a likely candidate for production of sodium atoms at these velocities. The total flux of sodium in the tail was ,1 times 1023 atoms s,1, which corresponds to 1 to 10% of the estimated total production rate of sodium on the planet. [source] Oral administration of a centrally acting ghrelin receptor agonist to conscious rats triggers defecationNEUROGASTROENTEROLOGY & MOTILITY, Issue 1 2009A. D. Shafton Abstract, Agonists of ghrelin receptors that cross the blood,brain barrier, but not ghrelin itself, administered peripherally (intravenous or subcutaneous), cause defecation by acting on centres in the lumbo-sacral spinal cord. It is not established whether orally administered ghrelin receptor agonists can have this action. We tested GSK894281 for its effectiveness at the ghrelin receptor and its ability to cross the blood,brain barrier. GSK894281 was effective at the human and rat ghrelin receptors at 1,10 nmol L,1, but was >1000-fold less potent at the motilin receptor. It achieved a similar blood concentration by oral or intravenous administration. Oral bioavailability was 74% and brain : blood ratio at steady state was 0.7 : 1. GSK894281 administered orally (1,100 mg kg,1) caused a prompt, dose-related production of faecal pellets; at 10 mg kg,1 faecal output was four times greater than after carrier. The output was the greatest in the first half hour and subsided over the next 90 min. At an oral dose of 10 mg kg,1, the compound was effective on eight successive days. Faecal output was, on average, increased threefold over control in the 2 h after administration on each of the 8 days. This dose also significantly increased food consumption. Rats showed no adverse behavioural effects to the drug on a single application, but at the end of a week of administration they avoided the gavaging pipette. Oral administration of ghrelin receptor agonists that enter the central nervous system could possibly be used to relieve acute cases of constipation or to clear the bowel for colonoscopy. [source] Lucidity in a woman with severe dementia related to conversation.JOURNAL OF CLINICAL NURSING, Issue 7 2005A case study Aims and objectives., The aim of this study was to explore the presence of lucidity in a woman with severe dementia during conversations and whether it occurred when conversational partners or the woman with severe dementia initiated the conversation topics about the present, past or future time and whether she was presented with support or demands during the conversation. Background., Communication problems as well as episodes of lucidity in people with dementia are reported in the literature. Design., A researcher held 20 hours of conversation with a woman with severe dementia. A daughter participated for about three and a half hours. The conversation was tape-recorded and transcribed verbatim. Methods., The text was divided into units of analysis. Each unit of analysis was then assessed separately and discussed among the authors. Chi-square tests and logistic regression analysis were performed. An ethics committee approved the study. Results., The woman as initiator of the conversation topic and support to the women during conversation from the conversation partner were found to be the most significant factors explaining lucidity, while conversation about the present or past time showed no connection with lucidity. Very few topics (n = 7) concerned future time and they were not used in the statistical analysis. The researcher initiated 41%, the woman 43% and the daughter 16% of the topics. Support was registered in 49%, demands in 15% and both support and demands in 16% of the units of analysis. There were 58% topics about present and 40% about the past time. Conclusions., The presented study is a case study and the results cannot be generalized. For the woman with severe dementia, lucidity was promoted by the conversational parties carefully focusing on conversation topics initiated by the woman while supporting her during conversation. Relevance to clinical practice., To share the same perception of reality, focusing on the topics initiated by the patient with severe dementia and a supporting attitude to what the patient tells, will hopefully give more episodes of lucidity in the patient. This approach in caring for patients with severe dementia might give more meaning and well-being to the conversational partners in daily care. [source] | ||||||||||