Embolized air collection in the superior vena cava of "upright" sheep

In 34 studies on six "upright" anesthetized sheep central venous pressure from sites in the upper and lower superior vena cava (SVC) was recorded before, during, and after the injection into a neck vein of 1-ml increments of air every minute for 15 min. After the injection of air, the pressure recorded from the upper site increased significantly. This increase was the result of air collecting in the SVC with a consequent loss or partial loss of the SVC hydrostatic pressure difference. The time of onset and the duration of collection were not influenced by hyper- or hypovolemia nor by 1 kPa positive end-expiratory pressure. The readily identifiable change in the venous pressure in the upper SVC provided an earlier and more reliable warning of these small-volume air emboli than did a Doppler probe directed at the right side of the heart.     

Direct measurement of human plasma corticotropin-releasing hormone by "two-site" immunoradiometric assay

A "two-site" immunoradiometric assay (IRMA) which allows the direct estimation of human CRH (hCRH) in plasma is described. Using this IRMA, basal levels of CRH in normal subjects ranged from 2-28 pg/mL [mean, 15 +/- 7 (+/- SD) pg/mL; n = 58]. Values in men and women were similar. Plasma CRH values within this range were also found in patients with Cushing's syndrome, Addison's disease, and Nelson's syndrome, with no correlation between plasma CRH and ACTH levels in these patients. Elevated plasma CRH levels were found in pregnant women near term [1462 +/- 752 (+/- SD) pg/mL; n = 55], and the dilution curve of this CRH-like immunoreactivity paralleled the IRMA standard curve. After its immunoadsorption from maternal plasma, this CRH-like material eluted on reverse phase high performance liquid chromatography with a retention time identical to that of synthetic CRH and had equipotent bioactivity with the synthetic peptide in the perfused anterior pituitary cell bioassay. Circulating CRH was not detected in Wistar rats, even after adrenalectomy and subsequent ether stress. Synthetic hCRH was degraded by fresh human plasma relatively slowly; 65% of added CRH remained after 1 h of incubation at 37 C. Degradation was inhibited by heat treatment (54 C; 1 h), cold treatment (4 C; 4 h), or freezing and thawing. Loss of synthetic rat CRH occurred more rapidly when fresh rat plasma was used; only 20% of added CRH remained under the same conditions. The inability to measure CRH in peripheral rat plasma may be due to the presence of active CRH-degrading enzymes which fragment the CRH molecule into forms not recognized by the CRH IRMA.     

The Frequency and Context of Snacking among Children: An Objective Analysis Using Wearable Cameras

Snacking is a common eating behaviour, but there is little objective data about children’s snacking. We aimed to determine the frequency and context of children’s snacking (n = 158; mean age = 12.6 years) by ethnicity, gender, socioeconomic deprivation and body mass index (BMI) children. Participants wore wearable cameras that passively captured images of their surroundings every seven seconds. Images (n = 739,162) were coded for snacking episodes, defined as eating occasions in between main meals. Contextual factors analysed included: snacking location, food source, timing, social contact and screen use. Rates of total, discretionary (not recommended for consumption) and healthful (recommended for consumption) snacking were calculated using negative binomial regression. On average, children consumed 8.2 (95%CI 7.4, 9.1) snacks per day, of which 5.2 (95%CI 4.6, 5.9) were discretionary foods/beverages. Children consumed more discretionary snacks than healthful snacks in each setting and at all times, including 15.0× more discretionary snacks in public spaces and 2.4× more discretionary snacks in schools. Most snacks (68.9%) were sourced from home. Girls consumed more total, discretionary and healthful snacks than boys, and Māori and Pacific consumed fewer healthful snacks than New Zealand (NZ) Europeans. Results show that children snack frequently, and that most snacking involves discretionary food items. Our findings suggest targeting home buying behaviour and environmental changes to support healthy snacking choices.     

Controlled studies of intranasal immunotherapy for ragweed pollenosis

During 1978 a double blind study compared the efficacy of preseasonal short ragweed (RW) extract intranasal immunotherapy with a histamine placebo; in 1979 more prolonged treatment with a larger dose of polymerized ragweed (PRW) was evaluated. In neither year did the placebo-treated patients show significantly more severe disease as assessed by daily symptom diaries, examination in season, comparison of overall symptom severity with previous years or changes in nasal challenge tests. Following treatment in 1979 there was a significantly greater amount of secretory IgA and IgG ragweed antibodies secreted by the nose of the PRW-treated group, but these titers did not correlate with clinical results.     

Angiography in poor-risk patients with massive nonvariceal upper gastrointestinal bleeding

The purpose of this retrospective study was to determine the diagnostic and therapeutic usefulness of gut angiography in patients with massive upper gastrointestinal bleeding from a nonvariceal source. All patients (n = 64) in this category who underwent a gut angiogram between 1980 and 1986 were studied. Pre-angiogram endoscopy was attempted in all patients and was nondiagnostic in 14 (22%). Contrast extravasation at angiography was seen in 25 of 64 patients (39%), and in over half of these patients endoscopy was nondiagnostic (n = 11) or wrong (n = 3). Attempts to control bleeding in this group by selective arterial embolization (n = 14) or intra-arterial vasopressin (n = 11) successfully averted operation in 13 of 25 patients (52%) and was associated with a 50% reduction in mortality (83% versus 38%). Selective embolization of vessels thought to be bleeding on clinical grounds without evidence of contrast extravasation (i.e., "blind" embolization) was not helpful in controlling hemorrhage. Urgent gut angiography in patients with massive upper gastrointestinal bleeding of arteriocapillary source is a useful diagnostic and therapeutic maneuver and warrants continued application in this group of poor-risk patients.     

Trends in hotel patronage and drink driving in Hobart, Tasmania

From 1990 to 1991 in the Hobart region there was a marked fall in both hotel patronage and the proportion of patrons subsequently driving with their blood alcohol concentration above the legal limit. This was associated with smaller falls in the number of drink drivers charged and alcohol-related road accidents, which continued in the following year. It appears that the pattern of drinking and driving is changing, presumably in response to random breath testing and tougher penalties for offences.     

Innovations in neonatal case management: an integrated, data-driven approach

The intent of this article is to provide one company's perspective on the challenging and complex care management of the high-risk neonate. The strategies presented herein should enable and encourage case managers to implement an integrated management process for the frail neonatal population.     

Determination of dihydroergotamine in human plasma by high-performance liquid chromatography with fluorescence detection

Dihydroergotamine, a 5-hydroxytryptamine antagonist, is used for the treatment of vascular headaches. A high-performance liquid chromatography assay with fluorescence detection is described for the determination of dihydroergotamine in plasma. The assay was validated over the concentration range 0.1-10 ng/ml plasma and applied to the analysis of plasma samples from subjects treated intramuscularly and intranasally with 2 mg of dihydroergotamine.