A population-based study of the coverage of cancer patients by hospice services

The aims were to determine the proportion of terminal cancer patients in South Australia who had involvement with a programme of hospice care, to identify the predictors of hospice involvement, and to consider the influence of hospice services, along with other variables, on the place of death. A file of patients of the State's hospice services who died in 1990 was compiled and linked to the population-based Central Cancer Register. We found that 1561 (56%) of the 2800 cancer patients who died in 1990 had care from a hospice service. Patients were less likely to be involved with a hospice service if they were 80 years or older, lived in a rural region, or had a haematological malignancy, and more likely to have hospice care if they had a survival time of more than six months, or were born in the UK or Europe. Patients of hospice services were more likely than other patients to die at home or in an inpatient hospice, and less likely to die in a nursing home or private hospital. A range of other factors were also found to be associated with place of death. We conclude that there has been a rapid acceptance of hospice care in South Australia, with a majority of the target population of cancer patients covered by services. Epidemiological research methods are useful for identifying gaps in the provision of care, and for determining the impact of various factors on where people die. This research is, therefore, important for the formulation and evaluation of policy for the delivery of terminal care.

Cost-effectiveness of Helicobacter pylori eradication for the long-term management of duodenal ulcer in Canada

BACKGROUND

A 1994 National Institutes of Health consensus panel recommended that eradication of Helicobacter pylori should be first-line therapy for persons with duodenal ulcer.

OBJECTIVE

To assess the cost-effectiveness of H pylori eradication relative to alternative pharmacologic strategies in the long-term management of persons with confirmed duodenal ulcer.

METHODS

Decision analysis model to estimate expected costs and symptomatic ulcer recurrences during a 12-month period for three general treatment strategies: (1) immediate H pylori eradication; (2) H pylori eradication at first ulcer recurrence; and (3) continuous maintenance therapy with a histamine2 receptor antagonist (ranitidine hydrochloride). Two H pylori eradication therapies were compared: classic triple therapy and omeprazole plus amoxicillin. Probabilities for ulcer recurrence are by meta-analysis of published randomized trials. Health care resources used in the management of duodenal ulcer recurrence were by expert physician panel. All costs are in 1993 Canadian dollars.

RESULTS

Duodenal ulcer recurrence at 6 months (symptomatic and asymptomatic) with placebo was 65.4% and 12.8% with maintenance ranitidine therapy. Where eradication of H pylori was successful (85% of patients), the ulcer recurrence rate to 12 months was 3.7%. Treatment with ranitidine and triple therapy to eradicate H pylori on first presentation has an expected 1-year cost of $253 with 15 symptomatic recurrences per 100 patients; H pylori eradication by omeprazole plus amoxicillin had similar expected costs ($272) and outcomes (15 recurrences per 100 patients). Both of these early H pylori eradication strategies were dominant (less costly with same or better outcomes) over intermittent or continuous maintenance ranitidine therapy or delayed (after first recurrence) H pylori eradication.

CONCLUSION

Our analysis provides economic evidence in support of the recent guidance that for persons with duodenal ulcer, early attempts to eradicate H pylori are recommended.

The effectiveness of esophageal stethoscopy in a simulated in-flight setting

PURPOSE

Previous research has confirmed the inability of flight nurses in an airborne BO-105 helicopter to hear breath sounds using normal or amplified transthoracic stethoscopy. The purpose of this study was to determine whether esophageal stethoscopy enabled effective auscultation of breath sounds in a simulated in-flight environment.

METHODS

The cabin-sound environment of an in-flight BO-105 was recorded and recreated in an audiology laboratory, where five flight nurses were evaluated listening to taped breath sounds via an esophageal stethoscope. This audiotape model, validated in a previously published study, used a tape consisting of 24 20-second segments. Each segment, the beginning of which was marked with a beep signal, consisted of 20 seconds of silence or breath sounds. The distal (esophageal) end of the esophageal stethoscope was attached to the tape recorder; the intensity level of breath sounds heard at the stethoscope earpiece was calibrated to equate the sound level of actual esophageal breath sounds recorded on a volunteer.

RESULTS

All nurses correctly identified the 24 taped segments as silent or including breath sounds 100% of the time.

CONCLUSION

In the simulated environment tested, esophageal stethoscopy enabled 100% accuracy in identification of breath sounds, as compared with previously reported 0% efficacy for standard transthoracic auscultation. Study in the actual patient-care environment is indicated to confirm the usefulness of esophageal stethoscopy in the in-flight setting.

Structural requirements for addition of O-linked carbohydrate to recombinant erythropoietin

To define the structural requirements for addition of O-linked glycosylation in vivo, recombinant erythropoietin (rEPO) variants were constructed. Thirty-three independent Ser or Thr substitutions were constructed and examined to see which were subject to O-linked carbohydrate addition. Variants with Thr mutations at positions 123 and 125, but not elsewhere, contained additional carbohydrate, which suggests that several positions around the existing O-linked glycosylation site (Ser126), but not elsewhere, contain the necessary information for O-linked carbohydrate addition. Two forms of the Thr125 variant were identified. One form was glycosylated only at residue 125, and a second form was glycosylated at both Thr125 and Ser126, the normal O-glycosylation site. We have also found that glycosylation is less efficient when rEPO is improperly folded and that prolines at -1 and +1 relative to the O-glycosylation site enhance glycosylation.

Visible scars and self-esteem in pediatric patients with burns

The supposition of often made that visible scarring is more psychologically damaging than are "hidden" burn scars, but little evidence exists to support that idea. We compared the self-evaluations of 28 male and 21 female pediatric patients with burns to the amount and visibility of scars. Males were 6 to 18 years old at the time of burn and sustained 15% to 99% total body surface area burns. They were evaluated 1 to 6 years after their burn injury. Females constituted a similar group. They were 5 to 18 years old at the time of burn, sustained 15% to 94% total body surface area burns, and were evaluated 1 to 7 years after their burn injury. All of the children underwent evaluation with the Piers-Harris Children's Concept Scale, evaluating themselves on intellectual and school status, physical appearance, anxiety, happiness and satisfaction, and behavior and popularity. Scores from these parameters were compared against each child's "visible" scars as seen on the face, head, neck, and hands. Also, comparisons were made with the numbers of reconstructive needs in these areas. Significant inverse correlations were found in the males. As the number of scars increased in these areas, the patient's scores for "physical appearance" and "happiness and satisfaction" decreased (p < 0.001). Other psychologic parameters were not affected. There was no effect by age of patient, and no significant correlations were found for the female group. The results emphasize the importance of the burn team's awareness that pediatric survivors of burns may appear superficially to be adjusting well, while harboring grave self-deprecating feelings. Those with "visible" scars will need special support to enhance self-esteem.

Receiver operating characteristic evaluation of computer display of adult portable chest radiographs

RATIONALE AND OBJECTIVES

The suitability of using an image console monitor for interpretation of adult portable chest radiographs was evaluated with receiver operating characteristic (ROC) analysis and subjective techniques.

METHODS

Radiologists read 80 chest images, once on a display monitor and once on computed radiography film, for the presence or absence of pneumothorax or atelectasis. Judgments of correct or incorrect positions of tubes and lines were reported, and total viewing time was recorded.

RESULTS

A statistically significant difference was found in favor of monitor reading for detection of pneumothoraces. Atelectasis detection also was higher with monitor reading, but the difference did not reach statistical significance. Tube/line judgments were equivalent for both modes. Total viewing time was approximately 1 minute longer per image with the monitor.

CONCLUSIONS

Viewing computed radiography images on a workstation monitor does not seem to affect diagnostic accuracy compared with film viewing. Preset image defaults tailored to the individual radiologist could decrease total viewing time to acceptable levels.

Method for simultaneous isolation and quantitation of platelet activating factor and multiple arachidonate metabolites from small samples: analysis of effects of Staphylococcus aureus enterotoxin B in mice

A novel method has been developed for the extraction and simultaneous separation and quantitation of key arachidonate metabolites and platelet activating factor (PAF) from plasma samples of limited size. Aqueous solutions of these metabolites were added onto a solid phase C-18 cartridge and arachidonate metabolites and PAF were eluted, successively, with acetonitrile-methanol (85:15, v/v), followed by 100% methanol. Arachidonate metabolites (first eluate) were fractionated by C-18 reverse-phase high-performance liquid chromatography using a program designed for the resolution of 31 arachidonate metabolites (3-min separation). The fractions were collected and assayed by radioimmunoassay or radiography, if radioactively labeled. Two internal standards were added to each sample, 15-hydroxyeicosadienoic acid (detected at 235 nm) to determine gradient shifts and [1-14C]eicosatrienoic acid to estimate the recoveries of arachidonate metabolites at any stage of the process. This method was developed to answer specific questions concerning the mode of action of Staphylococcus aureus enterotoxin B (SEB). Plasma samples from mice challenged with SEB were analyzed and major differences were seen in 5-lipoxygenase metabolites. Low doses of SEB vs saline stimulated 5-hydroxyeicosatetraenoic acid production, while high doses of SEB stimulated leukotriene D4 production.

Armadillos (Dasypus novemcinctus) as a model to test antileprosy vaccines; a preliminary report

The efficacy of two candidate leprosy vaccines, BCG and a mixture of BCG and killed Mycobacterium leprae, was tested in 62 armadillos caught in the wild. The abilities of the vaccines to convert lepromin-negative armadillos to a positive reaction were compared with a group of control animals. Both vaccines upgraded subsequent lepromin skin-test histopathology. The conversion results parallel the protection values obtained in some BCG vaccine trials against leprosy in humans. Before conducting expensive human trials with new antileprosy vaccines, it would be worthwhile first to evaluate them in the armadillo model.

Trends in the terminal care of cancer patients: South Australia, 1981-1990

BACKGROUND

The increasing numbers of cancer patients, the high costs of terminal care, and the development of palliative care services have led to a growing interest in patterns of terminal cancer care. These patterns are relevant to the formulation and evaluation of health services policy.

AIMS

To investigate trends in the place of death of South Australian cancer patients between 1981 and 1990, and to examine associations of socio-demographic and clinical variables with the place of death.

METHODS

Data relating to 2715 deaths attributed to cancer in 1990 were extracted from the Central Cancer Registry. To assess trends, these data were directly standardised to the age-sex distribution of cancer deaths in 1981 and 1985 which were investigated in a previous study. Unconditional logistic regression was used to investigate predictors of place of death.

RESULTS

The proportion of deaths which occurred in major metropolitan public hospitals decreased from 40% in 1981 to 28% in 1990. Conversely, the proportion which occurred in hospice units increased from 5% to 20% over the same period. There was a decline in the proportion of deaths which occurred in private hospitals, but there was no significant change in the proportion which occurred in country hospitals or nursing homes. The proportion of deaths at home remained around 14%. Associated with place of death were age, sex, type of malignancy, survival time from diagnosis to death, Aboriginality, and area of residence. Further research to assess the clinical appropriateness of terminal care patterns is suggested.

Helicobacter pylori infection in adolescents with eating disorders and dyspeptic symptoms

The potential role of Helicobacter pylori infection of the antrum as a cause of symptoms of dyspepsia in patients with eating disorders was evaluated with an assay to detect H. pylori-specific IgG in serum. H. pylori-specific optical-density readings were comparable for adolescents with eating disorders (0.133 +/- 0.063, mean +/- SD) and for two comparison groups, and were lower than readings for children with documented H. pylori infection. Symptoms referable to the gastrointestinal tract did not correlate with H. pylori status in the teenagers with eating disorders.

Therapeutic role of dietary fibre

The current status of dietary fibre and fibre supplements in health and disease is reported, and the components of dietary fibre and its respective mechanical and metabolic effects with emphasis on its therapeutic potential are reviewed. Practical management guidelines are provided to help physicians encourage patients identified as having fibre deficiency to increase dietary fibre intake to the recommended level.

Parental stress as a cause and effect of pediatric burn injury

The current study reports assessments of stress for parents of children with acute burns at the time of hospital admission and during the first 5 years after injury. At each assessment, parents of children with burns report neither more nor less stress than a normal population. At the time of admission, parents of children with acute burns do not differ from the normal sample on any of the measures of parenting stress. Parents of recovering children with burns do report significant changes. They report significantly higher depressive symptoms at year 2 after the child's burn injury and lower than normal levels of depression in years 4 and 5 after the child's injury. During the recovery period, these parents also attribute their stress more often to the child with burns, whereas other parents more evenly divide blame among their children and their personal characteristics.

Social competence and behavioral problems of pediatric survivors of burns

Sixty children (35 boys, 25 girls) with burns were surveyed at least 1 year after burn injury to assess the behavior problems and difficulties with competency that they were having. The Child Behavior Checklist, the Youth Self Report, and the Teacher Report Form developed by Achenbach were administered to obtain standardized measures of behavior and competence. The mean values for these scales were in the normal range for each age and sex. However, the Child Behavior Checklist revealed a statistically significant (p < 0.05) increase in problems and decrease in competency for most age groups and both sexes when compared with the reference population. In contrast, the Teacher Report Form and the Youth Self Report revealed very few differences from the reference population. The burn size (15% to 20% total body surface area, 35% to 50% total body surface area, and > 70% total body surface area) did not account for any of the group differences. Further studies involving detailed clinical interviews and other standardized measures are needed to understand the discrepancies between the Child Behavior Checklist and the other scales.

Increased lymphatic pumping ability in pregnant ewes

OBJECTIVE

Daily the lymphatic system returns several liters of fluid to the systemic circulation. Unlike blood, lymph is pumped against a pressure gradient. Because vessels in the systemic circulation are hyporesponsive to vasoconstrictor hormones during pregnancy, we decided to assess whether lymphatic pumping ability was decreased during pregnancy.

STUDY DESIGN

Ten pregnant ewes were chronically catheterized in the left thoracic duct and jugular vein. Four days after surgery thoracic duct pumping ability was determined by measuring the lymph flow rate as a function of outflow pressure by varying the height at which lymph flow drains in an open-flow system.

RESULTS

Lymph flow was plotted against outflow pressure, and the value at which lymph flow decreases is defined as the "breaking point." The outflow pressure at which lymph flow equals zero is the "stopflow" pressure; this value defines the pumping ability. The pregnant ewes had a breaking point of -1 +/- 2.7 versus 14.4 +/- 3.0 mm Hg (mean +/- SD) for the nonpregnant sheep. Stopflow pressures were 62 +/- 7.3 versus 23.9 +/- 4.7 mm Hg (mean +/- SD) for the nonpregnant ewes (p < 0.05).

CONCLUSIONS

The ability of the lymphatic system to generate pressure is increased during pregnancy, but the breaking point is diminished. Alterations of lymphatic pumping ability could explain fluid retention under pathophysiologic conditions.

Glucose turnover and its regulation during intense exercise and recovery in normal male subjects

Intense exercise to exhaustion is expected to be associated with rapid and large changes in glucose production (Ra) and utilization (Rd). To quantify these, and to determine their mechanisms and those of the prolonged postexercise hyperglycemia, we measured circulating metabolic regulators and glucose kinetics, the latter by the method of enriched tracer [3-3H] glucose infusion during exercise. Eighteen fit, lean young male subjects exercised to exhaustion at 80% of maximal workload (approximately 100% VO2max) on a cycle ergometer. Plasma glucose was 4.90 +/- 0.08 mM/L at rest, increased during exercise, then abruptly to 6.91 +/- 0.40 mM/L at 4 min recovery then gradually declined. Plasma insulin was constant during exercise, then doubled to 162 +/- 28 pmol/l until 20 min recovery, before declining. Plasma glucagon increased by 71 +/- 11 pg/mL. Plasma norepinephrine increased 18-fold and epinephrine 14-fold, both declining by 20 min recovery. Ra increased 7-fold by exhaustion to 13.0 +/- 1.18 mg/kg/min, then decreased to 2.43 +/- 0.24 mg/kg/min by 9 min, then to about 2 mg/kg/min the rest of recovery. Rd rose 3-fold (6.61 +/- 0.70 mg/kg/min), and remained lower than Ra to 7 min recovery, but thereafter declined more slowly. Thus, the rapid and extremely large increase in Ra was not matched by the increment in Rd during exercise and early recovery. We suggest that unlike in exercise of lesser intensity, the major mediators of both the increase in Ra and the restraint of the increase in Rd are the catecholamines. The post exercise hyperglycemia and hyperinsulinemia are appropriate to muscle glycogen repletion.

Staphylococcus aureus enterotoxin B challenge of monkeys: correlation of plasma levels of arachidonic acid cascade products with occurrence of illness

Arachidonic acid cascade products have been shown to be increased in vitro in Staphylococcus aureus enterotoxin B (SEB)-treated epithelial cell cultures in our laboratory. In order to confirm that these products were clinically related to SEB intoxication, monkeys were administered SEB by nasogastric intubation. It caused emesis in five of six monkeys (less than 4 h), and the sixth monkey showed signs of mild illness. The monkeys which vomited continued to display signs of gastrointestinal illness beyond 8 h but were without any apparent signs of illness by 24 h. Blood samples were collected prior to SEB administration, upon first indication of illness, and at twice that time interval. One week prior to SEB treatment, the same monkeys were administered saline by nasogastric intubation and in every way handled similarly in order to serve as their own controls. Blood samples were taken from the control animals at 0, 4, and 8 h. The plasma concentrations of prostaglandin E2 (PGE2), leukotriene B4 (LTB4), and 5-hydroxyeicosatetraenoic acid (5-HETE) did not vary significantly throughout the 8-h experiment for saline-treated controls, nor did they differ from the concentrations found in the plasma of monkeys just before administration of SEB. When the SEB-treated monkeys showed the first indication of illness (less than 4 h), the mean of the concentration in plasma of PGE2 increased 1.44-fold, that of LTB4 increased 2.23-fold, and that of 5-HETE was essentially unchanged. At twice the time interval of the first display of illness (less than 8 h), PGE2 was still elevated (1.48-fold), LTB4 had decreased slightly to 1.66-fold, and 5-HETE had soared (3,45-fold), suggesting a divergence in the enzymatic utilization of the parent compound of the latter two metabolites, 5-hydroperoxyeicosatetraenoic acid. These studies suggest that arachidonic acid cascade metabolites were a consequence of SEB intoxication and may provide a logical site for metabolic interference in SEB-induced toxicity.

Detection of breast abnormalities on teleradiology transmitted mammograms

The authors conducted an observer performance study to compare breast lesion detection of conventional mammography (CM) with teleradiology (TE) transmitted mammograms. One hundred four abnormal, single-projection mammographic images were transmitted by teleradiology. Abnormalities included 11 cases with skin thickening or retraction, 48 cases with microcalcifications, and 52 with parenchymal masses. The CM and TE images were reviewed by four mammographers who indicated the type and location of abnormalities and a level of confidence for their diagnostic decisions. For each of three detection tasks--skin and nipple abnormalities, microcalcifications, and masses--receiver operating characteristic curve analysis was performed for individual readers and all readers as a group. For detecting skin and nipple abnormalities, readers performed significantly better with CM than with TE (z = 2.05, P = less than 0.04). However, no significant differences were found among readers for detection of either microcalcifications or masses. Further improvements in hardware and imaging parameters may improve detection of soft tissue abnormalities. Further evaluation is necessary to determine whether teleradiology might be applicable to breast cancer screening.

Roger Hunt negotiates a new academic affiliation. Interview by Donald E.L. Johnson

Roger Hunt is president and chief executive officer of Lutheran General Hospital, Park Ridge, Illinois. The north suburban Chicago hospital recently signed a letter of intent to shift its primary academic affiliation to the University of Chicago Medical School, which is on the south side of the city. More than 20 miles and more than an hour of freeway and city street driving separate the organizations. Health Care Strategic Management's editor and publisher, Donald E.L. Johnson, talked with Roger Hunt about Lutheran General's strategy for selecting a medical school and creating a teaching program that works for all concerned.

Absence of any male-specific antigen recognized by T lymphocytes in X/XSxr' male mice

Previous work has established that whereas X/X mice carrying the sex-reversing chromosomal fragment Sxr are positive for the male-specific transplantation antigen, H-Y, X/X mice carrying the variant Sxr', although they too develop as phenotypic males, are H-Y negative. In this paper we show that X/XSxr' male mice do not express any male-specific antigen that can induce skin-graft rejection.

Prevalence and significance of positive Mitsuda reaction in the nine-banded armadillo (Dasypus novemcinctus)

One hundred two armadillos captured from the wild were lepomin tested. Nine of them (8.8%) showed a positive Mitsuda reaction. The histopathological appearance of the reaction had a spectrum showing tuberculoid, borderline tuberculoid, borderline lepromatous, and lepromatous histology. It is possible that armadillos can develop all the different types of leprosy seen in humans. The armadillo is a good animal model to test protective vaccines against leprosy.

Where patients with cancer die in South Australia

In a sample of 1582 deaths among South Australian patients with cancer (795 deaths in 1981 and 787 deaths in 1985), 67% of deaths occurred in a hospital, 9% of deaths in a hospice, 10% of deaths in a nursing home, and 14% of deaths in a private residence. More patients died in a hospice or nursing home in 1985 than in 1981, and fewer died in a hospital. With increasing age, fewer patients died in a hospital and more in a nursing home. Compared with men, women were less likely to die at a private residence and more likely to die in a nursing home. A greater proportion of men with a living wife died at a private residence than was so among single or widowed men. However, conjugal status was not associated with the place of death of women. Patients who lived in the more affluent metropolitan suburbs tended more to die at a private residence than did those from poorer suburbs or country areas. Patients with haematological malignancies died in major metropolitan public hospitals more frequently than did patients with other tumours. Possible explanations are given for these findings.

Our experiences with breeding of nine-banded armadillos (Dasypus novemcinctus) in captivity

The nine-banded armadillo is considered the best animal model in the study of leprosy. Armadillos have never been successfully bred in the laboratory and therefore animals required for the experiments are captured from the wild and are likely to carry many diseases including leprosy. An attempt was made to breed them in captivity. Our attempt to house them in various combinations in their natural environment in the farmlands of Louisiana was successful. Although a significant increase in conception and delivery was recorded, consistent breeding of the animals was not obtained.

Regulation of accessory cell function by retinoids in murine immune responses

This study examines the effects of in-vivo immune regulation by vitamin A acetate (VAA) and 13-cis-retinoic acid (13-CRA) on in-vitro accessory cell function. Mice were fed a control diet, or diet containing VAA or 13-CRA, and monitored by body weight gains and diet consumptions at weekly intervals. At 4, 7 and 12 weeks mice were killed, differential blood counts performed and accessory cells isolated from lymphomedullary tissues. Histology confirmed that the chief feature of the lymphomedullary organs of the VAA-fed animals was an expansion of the splenic marginal zone and the paracortical region of the lymph nodes. There was an increase in the number of accessory cells present, and this included both dendritic cells and macrophages. The accessory cell function of these cells was also increased, as evidenced by both alloproliferative and allocytotoxic responses in vitro. In 13-CRA-fed animals the effects were similar to those seen with VAA, but were less pronounced. We suggest that the primary effects of these compounds on in-vivo immunoregulation could be due to their promotion of accessory cell function.

Oral nimodipine reduces prostaglandin and thromboxane production by arteries chronically exposed to a periarterial haematoma and the antifibrinolytic agent tranexamic acid

The calcium antagonist nimodipine blocks the effects of many vasoconstrictors of cerebrovascular smooth muscle and may reduce the incidence of delayed cerebral ischaemia following subarachnoid haemorrhage though not necessarily by inhibiting the development of angiographic cerebral vasospasm. Post-haemorrhagic CSF contains abnormally large quantities of various eicosanoids that partly reflect enhanced production by cerebral arteries. Does nimodipine affect this process? The extra-arterial and intra-arterial production of PG6 keto-F1 alpha, PGE2, PGF2 alpha and TXB2 were measured in perfused common carotid arteries taken from rabbits in which the arteries had been ensheathed by blood clot in vivo for 7 days. All rabbits were given the antifibrinolytic agent tranexamic acid to retard resolution of the clot, and half were given oral nimodipine (2 mg/kg/day) for 10 days. Nimodipine significantly reduced the extra-arterial production of TXB2 during the third and fourth hours of perfusion and, less consistently, the production of PGF2 alpha, PGE2 and PG6 keto-F1 alpha. Lutrol, the solvent for nimodipine, had no such effect.

Salt tolerance in Aster tripolium L. I. The effect of salinity on growth

A study of the growth of the maritime halophyte Aster tripolium L. has been carried out over a range of salinity treatments. The regression approach to growth analysis using frequent small harvests has been used to allow 'continuous' measurement of growth over a period of 36 d. Salinity was applied with the major ions present in ratios typical of those found in seawater. Growth was inhibited in terms of both dry weight production and leaf expansion at salinity levels equivalent to 0.625 strength sea water (full culture solution 300) and above, with the greatest effect being seen in terms of leaf area. Aster tripolium did not show increased succulence at high salinity, leaf fresh weight to dry weight ratio in fact declined, whilst leaf fresh weight per unit area remained constant. It should be noted that the plants exhibit low growth rates due to the low light intensity used.

Dietary composition and renal function in healthy subjects

Increments in dietary protein intake can increase glomerular filtration rate (GFR) in humans, and the glomerular hyperfiltration induced by high protein intake has been incriminated in the progression of glomerulosclerosis related to age and a number of renal diseases. GFR (as 51Cr-EDTA clearance) was measured in 18 vegans, 16 lactovegetarians and 18 omnivorous control subjects, matched for age. Omnivores ate significantly more total protein and protein of animal origin than the other two groups. Vegetable protein comprised 100% of the vegans' daily protein intake and 64% of the lactovegetarians', both significantly higher than the omnivores' (32%). Vegans and lactovegetarians also ate more carbohydrate and fibre than omnivores, although fat intake was similar. Mean GFR was significantly lower in the vegans than in the omnivores (100 +/- 13 vs. 113 +/- 16 ml/min/1.73 m2; p less than 0.04) and was intermediate in the lactovegetarians (105 +/- 16 ml/min/1.73 m2). Omnivores had significantly higher mean urinary albumin excretion rate (p less than 0.05) than vegans, and higher mean diastolic blood pressure than both vegans and lactovegetarians (p less than 0.01). The vegan diet is associated with glomerular and systemic haemodynamic changes which may be beneficial in the prevention of glomerular sclerotic changes in health and disease.

Salt tolerance in Aster tripolium L. II. Ionic regulation

Measurements of tissue ion contents (Na, K and Cl) were carried out at frequent intervals on plants of Aster tripolium L. grown at a range of salinities for 36 d. Aster tripolium behaved as a typical halophyte showing high levels of inorganic ion accumulation even at low salinities. As salinity increased Na replaced K to a large extent in the shoot but root K was unaffected up to 500 mol m^-3 external NaCl. Shoot (Na + K) concentration on a tissue water basis was maintained constant in all treatments throughout the experiment, whereas shoot (Na + K) on a dry weight basis showed marked fluctuations in some treatments. An increase in (Na + K) per gram dry weight was, however, accompanied by a parallel increase in fresh weight: dry weight (FW : DW) ratio. Transport of (Na + K) to the shoot per unit root weight changed during the experiment in the manner expected, given the observed changes in shoot relative growth rate and FW : DW to result in a constant shoot (Na + K) concentration on a water basis. Chloride was the major balancing anion in the shoot at high salinity, but never accounted for more than 38% of the (Na + K) found in the root tissue. At all salinities (Na + K) salts accounted for the majority of the measured shoot sap osmotic potential. The interactions between salinity, growth, ion transport and osmotic adjustment are discussed.

T-cell depletion of allogeneic bone marrow prevents acceleration of graft-versus-host disease induced by exogenous interleukin 2

Highly purified human recombinant interleukin 2 (IL-2) markedly accelerated lethal GVHD in the H-2-identical B10.BR----CBA combination, but had no effect when the donor cells were depleted of mature (Thy-1.2-positive) T lymphocytes, indicating a strong immunopotentiating effect of IL-2 on mature T cells causing GVHD. In the same donor-host combination, IL-2 did not influence the recovery from the post-transplantation bone marrow aplasia. The results suggest that IL-2 could be considered for adjuvant hormonal therapy to enhance immune recovery in recipients of T-cell-depleted allogeneic marrow.

Physical activity, glucose tolerance, and diabetes mellitus: the Whitehall Study

In the Whitehall Study, 6,672 men aged 40-64 years completed a questionnaire concerning leisure time physical activity and had a capillary blood glucose measurement on a sample taken 2 h after a 50 g glucose load. An activity score was calculated by grouping subjects into three broad categories: inactive, moderately active, and active. In both univariate and multiple regression analysis no significant association between blood glucose level and activity score could be found. There were 49 previously diagnosed non-insulin-dependent diabetic men and 25 men with 2 h blood glucose levels exceeding 11.1 mmol/l. The proportion of men in each of these groups did not differ significantly between the three activity categories. In a 1:10 sub-sample (n = 1,650) of the whole Study population there was no relationship between glucose tolerance distribution and a measure of energy expenditure (kcal/kg body weight). In this population there is no evidence for relationship between glucose tolerance or non-insulin-dependent diabetes and reported leisure time physical activity, or between glucose tolerance and energy expenditure.

Autologous lymphoid cells exposed to recombinant interleukin-2 in vitro in the absence of antigen can induce the rejection of long-term tolerated skin allografts

The intraperitoneal (i.p.) administration of autologous spleen cells treated with recombinant interleukin-2 (IL-2) in vitro resulted in the rejection of C57BL/10ScSn (B10) skin grafts that had survived for 18 months on CBA/Ca mice tolerant to B10 alloantigens. Cytotoxic lymphocytes specific for the graft alloantigens, assayed by limiting dilution analysis, appeared after the breaking of this immunological tolerance, whereas they were not detectable in tolerant mice. In these mice the frequencies of precursor cytotoxic cells specific for third-party alloantigens were unaffected by the IL-2 treatment.

H-Y status of X/X Sxr' male mice: in vivo tests

Sex reversed X/X male mice carrying Sxr or the variant Sxr' were typed for expression of the male specific histocompatibility antigen H-Y, by skin grafting and by in vitro cytotoxic and proliferative tests. The X/XSxr males, like X/Y males, were H-Y positive by in vitro testing, and failed to reject semi-syngeneic male skin grafts. In contrast X/XSxr' males, like X/X females, were H-Y negative and rejected semi-syngeneic, male skin. Spleen cells from X/Y males sensitized C57BL/10 female recipients to reject syngeneic male skin rapidly, whilst immunization with X/X female or X/XSxr' male cells failed to stimulate such second-set responses. These data suggest that the H-Y antigen detected by cytotoxic T cells is the same as that detected by graft rejection responses, that the Sxr' variant is not a tissue-specific regulatory mutation, and that X/XSxr' individuals do not express H-Y antigen but nevertheless develop as phenotypic males.

Early postnatal administration of 5,7-dihydroxytryptamine: effects on substance P and thyrotropin-releasing hormone neurons and terminals in rat brain

Substance P, thyrotropin-releasing hormone (TRH) and serotonin are putative neurotransmitters which have been proposed to co-exist in some brain neurons. Our previous immunocytochemical and biochemical studies have demonstrated that 85-100% of all serotonin neurons are destroyed following neonatal 5,7-dihydroxtryptamine (5,7-DHT) treatment. In this study, we have determined the effect of neonatal 5,7-DHT and desipramine (DMI) treatment on the biochemical content and immunocytochemical localization of substance P and TRH throughout the brain. Interestingly, we have observed that virtually all substance P- and TRH-immunoreactive cells in the ventral pons-medulla are destroyed by the neurotoxin. However, peptide-containing neurons in other regions were not affected. Additionally, we measured the peptide content and found that TRH is significantly decreased in the spinal cord (-50%) and pons-medulla (-20%), but not in other brain regions. Substance P content was not significantly altered in any region, even after a greater than 90% reduction of serotonin. These data indicate that the co-localized substance P and TRH forms a small proportion of the total peptide in brain.

The role of dendritic cells in the initiation of immune responses to contact sensitizers. II. Studies in nude mice

Twenty-four hours after skin painting nude mice with picryl chloride, there was an increase in the number of dendritic cells (DC) isolated from the draining lymph nodes. This increased inflow or retention of DC in lymph nodes following skin painting is therefore unlikely to depend on interaction of DC with T cells. The DC obtained initiated primary proliferative responses in vitro in lymph node cells from congenic euthymic mice. Contact sensitivity developed in congenic mice when they received footpad injections of 60,000 DC from the lymph nodes of nude mice skin sensitized 1 day previously with picryl chloride or oxazolone. The initiation of delayed hypersensitivity was therefore independent of T-cell contamination within the donor DC.