Ascorbate sulfate: a urinary metabolite of ascorbic acid in man.

Ascorbate-3-sulfate is a significant metabolite of ascorbic acid excreted in human urine. The characteristics of this compound were determined in experiments in which labeling with carbon-14 and tritium was used coupled with cochromatography with synthetic ascorbate-3-sulfate (both labeled and not labeled with sulfur-35) in a variety of solvent and absorbent systems.

Hematopoietic studies in vitamin A deficiency.

Recent studies of experimental vitamin A deficiency in man led the authors to conclude that anemia may result from lack of vitamin A. A review of numerous nutrition surveys in underdeveloped countries enhanced the suspicion that deficiency of vitamin A does contribute to the prevalence of anemia. Preliminary studies of vitamin A-deficient rats confirmed previous observations that anemia may result from lack of this vitamin. The livers of these animals had very low concentrations of vitamin A but normal or increased concentrations of iron. The finding of anemia is in contrast with other reports that vitamin A deficiency may cause elevated values for hemoglobin and hematocrit. The authors suggest that loss of taste and smell as a result of deficiency may account for refusal of experimental animals to eat and drink enough to prevent inanitation and dehydration. The resulting hemoconcentration may mask the true hematological picture, which is one of anemia.

Accessory urethral channel communicating with the seminal vesicle.

A rare variety of accessory urethra communicating with the left seminal vesicle is reported. Communication was demonstrated between the prostatic urticle and the right seminal vesicle, but not the left. Infection of the accessory channel was managed conservatively with antibacterial therapy. The classification, diagnosis, and treatment for this anomaly are discussed.

Effect of phototherapy light, sodium bisulfite, and pH on vitamin stability in total parenteral nutrition admixtures.

The three sections of this study extend previous research into losses of vitamins A, C, E, thiamin, riboflavin, and folic acid from total parenteral nutrition (TPN) admixtures. First, phototherapy light on TPN admixtures containing one of four amino acid solutions was studied. Experimental conditions included presence or absence of Intralipid iv fat emulsion, plastic bag or glass bottle storage container, and storage time of up to 48 hrs. The second phase studied stability of the same vitamins (except vitamin E) for 48 hrs in admixtures containing the amino acid solution which has no bisulfite, in glass bottles; with or without Intralipid; and with added sodium bisulfite (final concentrations of 0, 1, 2, 3, 4, 5 and 10 mEq/liter). Third, vitamin C and thiamin levels were measured in admixtures containing the amino acid solution with no bisulfite, without Intralipid, stored in glass bottles with various bisulfite concentrations (0, 1, 2, or 3 mEq/liter) and three pH levels (5.5, 6.5, and 6.75 pH). Exposure of TPN admixtures to phototherapy light caused losses of vitamins A, C, and riboflavin. Intralipid inclusion significantly reduced losses of vitamin A and riboflavin, but did not appear to affect vitamin C levels. The smallest vitamin C losses were noted in admixtures containing amino acid solutions A or B. Phototherapy light did not affect thiamin levels. Bisulfite had no affect on vitamin C, riboflavin, or folic acid levels. Vitamin A levels were maintained with bisulfite concentrations less than 3 mEq/liter. At 3 mEq/liter bisulfite, admixtures with Intralipid showed 50% loss of vitamin A.(ABSTRACT TRUNCATED AT 250 WORDS)

Parenteral infusion with an admixture of amino acids, dextrose, and fat emulsion solution: compatibility and clinical safety.

Fat emulsions are increasingly utilized as intravenous calorie sources in patients requiring total parenteral nutrition. In the United States, they are traditionally administered separate from the dextrose/amino acid solution because of concern regarding physical stability and clinical safety when fat emulsions are administered, having been mixed with the dextrose solution. The separate infusion entails multiple manipulations of the infusion system with increased risk of contamination and sepsis and increased cost in maintaining two infusion lines. This prospective sequential two-phase clinical study evaluated solution compatibility and clinical safety of an admixture of fat emulsion (Intralipid 20%), dextrose, amino acids (Veinamine 8%), electrolytes, vitamins, and trace minerals. Continuous infusion of this solution in 25 adult patients from 2 to 35 days did not result in any adverse clinical reactions or abnormal laboratory parameters. Gross, visual examination and in vitro analysis of the admixture solutions revealed no physical instability or changes in fatty acid composition in admixture solutions stored at 4 degrees C for up to 6 weeks.

Peripheral vein infusion of dextrose/amino acid solutions +/- 20% fat emulsion.

The purpose of this study was to evaluate the incidence of phlebitis occurring during peripheral infusion of nutrient solutions with and without 20% fat emulsions. Eighty patients were randomly assigned to one of four groups: (1) dextrose/amino acids-630 mOsmol/liter; (2) dextrose/amino acids/fat emulsion-706 mOsmol/liter; (3) dextrose/amino acids-882 mOsmol/liter and; (4) dextrose/amino acids/fat emulsion-983 mOsmol/liter. The peripheral infusion site was examined daily and the number of changes in infusion sites were recorded and the degree of phlebitis encountered was graded. The four groups were similar in the mean number of iv site changes per patient and per day. The average grade of phlebitis was similar (0.23-0.27 events/day) among the four groups. Infiltration occurred more frequently with butterfly needle while phlebitis occurred more frequently with plastic angiocatheters. Patients appeared to tolerate peripheral infusion with high osmolar solutions just as well as lower osmolar solutions. Concurrent infusion with a 20% fat emulsion did not alter the number of iv site changes or the incidence or degree of phlebitis reported and thus, did not appear to have a protective effect on the vein when infused with dextrose/amino acid solutions.

Effect of Intralipid, amino acids, container, temperature, and duration of storage on vitamin stability in total parenteral nutrition admixtures.

This study was designed to determine the stability of certain vitamins added to total parenteral nutrition (TPN) admixtures with or without Intralipid iv fat emulsion and with each of four amino acid solutions stored in either glass bottles or plastic bags at either ambient room (25 degrees C) or refrigerator (5 degrees C) temperature for a 48-hr period. Riboflavin and folacin were not affected by the experimental conditions. The presence of Intralipid resulted in higher levels of vitamin E due to Intralipid's inherent vitamin E content; no other experimental conditions affected vitamin E. Thiamin levels decreased in admixtures containing the amino acid solution C and stored at 25 degrees C. Vitamin A levels were lower in admixtures stored in plastic but were maintained in admixtures containing Intralipid and stored in glass bottles at either temperature. Vitamin C levels were maintained in admixtures stored at 5 degrees C for all experimental conditions. The greatest vitamin C losses occurred in admixtures containing amino acid solutions C or D stored in plastic bags, or containing D stored in glass bottles at 25 degrees C.

Effects of a glucose meal on human pulmonary function at 1600-m and 4300-m altitudes.

The effects of a high-glucose meal on pulmonary function were observed in seven healthy males at medium (1,600 m) and high (4,300 m) altitude. Thirty minutes after the ingestion of 410 kcal (109.9 g cerelose) of glucose, peak serum glucose values were noted with a subsequent decrease over 3 h to below fasting levels at both elevations. At the same time, triglyceride levels continued to decline from 104.2 to 83.3 mg at 1,600 m and 103.7 to 80.5 mg/100 ml at 4,300 m, with differences being significant after 2 h. Both V-E and V-T increased in response to translocation to altitude; however, only V-T increased by 10.9% and 13.3% at 0.5 h for 1,600 m and 4,300 m, respectively. The V-o-2 increased during glucose elevation at 4300 m, while P-A-O2 remained essentially unchanged except for differences associated with translocation to altitude. A 13.9% increase was noted in D-L-CO followign glucose ingestion at 4,300 m along with a decreased triglyceride levels. The elevated D-L-CO values suggest an increase in gas exchange at the alveolar-capillary (A-c) level following the ingestion of a glucose meal for individuals transported to high altitude.

Educational clinical supervision: meeting the needs of specialist community practitioner students and professional practice.

In light of the possible demise of the community practice teacher, this paper proposes that a specific system of educationally led clinical supervision would benefit learning, teaching and assessing in the practice elements of specialist community practitioner education. Such a system would be additional to models of clinical supervision currently utilized in practice. An educative supervisory relationship would foster those skills and attributes essential for specialist community practice, enabling students to move toward mature responsible practice. It would provide experience of supportive frameworks that could be later utilized in professional practice. Clinical supervision specifically tailored for specialist community practitioner education would enable equity across branches and could be delivered in a variety of settings without a supervisor having to be 'on-site', thus benefiting comparatively isolated students in practice nursing and occupational health. To work successfully, educationally led clinical supervision necessitates a joint response by educational institutions and those practices where specialist community students undertake assessed placements. Without such a system in place to support specialist community practitioner courses, the standard of education and future practice cannot be assured.

Classifying specialist student practice: debates and dilemmas.

At present, the practice elements of the Specialist Community Practitioner Awards within the BSc (Hons) in the Community Health degree course at Manchester Metropolitan University do not directly contribute to degree classification. Student evaluation and external examiner concerns about the heavy assessment load motivated the course team to consider classifying practice at 20 Level III credits which would replace 20 theory credits. The process of developing a credible assessment tool for specialist practice was long and hard but the course team is now in a position to undertake an exploratory study of the assessment and classification of practice. This paper provides an overview of the discussion and debates that took place in the years before the study began. A future paper will provide detail of the study and will include practice educators, students and managers views on the structure, process and outcomes of marking specialist student practice in community settings.

The classification of specialist student practice: results of an exploratory study.

An exploratory study investigating the feasibility and acceptability of an assessment tool designed to allow practice educators(1)to classify Specialist Practitioner student practice, identifies issues of interest to all educators involved with practice assessment. Within 3 months of commencing education leading to Specialist Practitioner Awards, the spread of marks awarded for practice achievements was already consistent with final degree classification and within 6 months slightly higher than normal. By the end of the course, continued improvements in practice achievements resulted in 73% of practice marks being 70% and over. The implications for total degree classification are less catastrophic than they appear; even if this trend continues there will only be a slight increase in first class Honours degrees. Although the strategy for practice assessment includes practice educators and students working together to discuss and agree marks for practice achievements, in the study practice educators and students provided marks intentionally without discussion or consultation with each other. Two comparisons of these marks showed that many students overestimate or underestimate their practice achievements as perceived by practice educators. Continuous monitoring of how marks are determined will be a priority for the Specialist Practice team. In most cases, practice educators considered the marked assessment of practice to be a reasonable working proposition, though there were concerns about the timing of assessments and the applied terminology. The main conclusions are that some practice educators may award marks for effort, despite contradictory written comments, and that the ability of specialist students to self-assess remains an unknown quantity but a potential moderating influence. The role of the HEI will be to ensure essential preparation and ongoing support for practice educators to enable a tri-partite assessment process and to provide a robust strategy for internal and external moderation. The marked assessment of practice was implemented in September 2000; to date progress has been remarkably unproblematic with practice educators and students accepting the process with relative ease and much enthusiasm.

A high-fat diet elicits differential responses in genes coordinating oxidative metabolism in skeletal muscle of lean and obese individuals.

CONTEXT: In lean individuals, increasing dietary lipid can elicit an increase in whole body lipid oxidation; however, with obesity the capacity to respond to changes in substrate availability appears to be compromised. OBJECTIVE: To determine whether the responses of genes regulating lipid oxidation in skeletal muscle differed between lean and insulin resistant obese humans upon exposure to a high-fat diet (HFD). DESIGN AND SETTING: A 5-d prospective study conducted in the research unit of an academic center. PARTICIPANTS: Healthy, lean (n = 12; body mass index = 22.1 ± 0.6 kg/m(2)), and obese (n=10; body mass index = 39.6 ± 1.7 kg/m(2)) males and females, between ages 18 and 30. INTERVENTION: Participants were studied before and after a 5-d HFD (65% fat). MAIN OUTCOME MEASURES: Skeletal muscle biopsies (vastus lateralis) were obtained in the fasted and fed states before and after the HFD and mRNA content for genes involved with lipid oxidation determined. Skeletal muscle acylcarnitine content was determined in the fed states before and after the HFD. RESULTS: Peroxisome proliferator activated receptor (PPAR) α mRNA content increased in lean, but not obese, subjects after a single high-fat meal. From Pre- to Post-HFD, mRNA content exhibited a body size × HFD interaction, where the lean individuals increased while the obese individuals decreased mRNA content for pyruvate dehydrogenase kinase 4, uncoupling protein 3, PPARα, and PPARγ coactivator-1α (P ≤ 0.05). In the obese subjects medium-chain acylcarnitine species tended to accumulate, whereas no change or a reduction was evident in the lean individuals. CONCLUSIONS: These findings indicate a differential response to a lipid stimulus in the skeletal muscle of lean and insulin resistant obese humans.