Caring for patients with spinal metastasis during an MRI examination.

INTRODUCTION: Magnetic resonance imaging (MRI) is without question the best tool used for diagnosing and evaluating spinal metastasis. An MRI examination is known to be of great value for the treatment planning and survival of these patients. Radiographers have an important role in how the quality of care is experienced by the patients during an MRI examination. The purpose of the study was to describe the radiographers' perceptions of caring for patients with spinal metastasis during an examination with MRI. METHODS: Phenomenography was used to analyze the data in this study. Ten radiographers, one male and nine females were interviewed about their perception of caring for patients with spinal metastasis during an MRI examination. RESULTS: The findings showed that the radiographers' caring perspective influenced their approach towards what they consider to be essential in the care of patients with spinal metastasis. This can impact the extent of the adjustment to the care needs of the patients. Furthermore, the findings showed that there was a strong connection between the radiographers' care approach and preparedness to personalize the care. CONCLUSION: This study shows that it is important to be flexible when providing care for the patients. A person-centered care is achieved when the caring perspective is based on the patient's view and adjustments are made in agreement with the patient.

The prevalence of anemia and iron deficiency is more common in breastfed infants than their mothers in Bhaktapur, Nepal.

BACKGROUND/OBJECTIVES: Iron deficiency anemia is a widespread public health problem, particularly in low- and middle-income countries. Maternal iron status around and during pregnancy may influence infant iron status. We examined multiple biomarkers to determine the prevalence of iron deficiency and anemia among breastfed infants and explored its relationship with maternal and infant characteristics in Bhaktapur, Nepal. SUBJECTS/METHODS: In a cross-sectional survey, we randomly selected 500 mother-infant pairs from Bhaktapur municipality. Blood was analyzed for hemoglobin, ferritin, total iron-binding capacity, transferrin receptors and C-reactive protein. RESULTS: The altitude-adjusted prevalence of anemia was 49% among infants 2-6-month-old (hemaglobin (Hb) <10.8 g/dl) and 72% among infants 7-12-month-old (Hb <11.3 g/dl). Iron deficiency anemia, defined as anemia and serum ferritin <20 or <12 µg/l, affected 9 and 26% of infants of these same age groups. Twenty percent of mothers had anemia (Hb <12.3 g/dl), but only one-fifth was explained by depletion of iron stores. Significant predictors of infant iron status and anemia were infant age, sex and duration of exclusive breastfeeding and maternal ferritin concentrations. CONCLUSIONS: Our findings suggest that iron supplementation in pregnancy is likely to have resulted in a low prevalence of postpartum anemia. The higher prevalence of anemia and iron deficiency among breastfed infants compared with their mothers suggests calls for intervention targeting newborns and infants.

Irisin and FNDC5: effects of 12-week strength training, and relations to muscle phenotype and body mass composition in untrained women.

PURPOSE: To investigate the effects of strength training on abundances of irisin-related biomarkers in skeletal muscle and blood of untrained young women, and their associations with body mass composition, muscle phenotype and levels of thyroid hormones. METHODS: Eighteen untrained women performed 12 weeks of progressive whole-body heavy strength training, with measurement of strength, body composition, expression of irisin-related genes (FNDC5 and PGC1α) in two different skeletal muscles, and levels of serum-irisin and -thyroid hormones, before and after the training intervention. RESULTS: The strength training intervention did not result in changes in serum-irisin or muscle FNDC5 expression, despite considerable effects on strength, lean body mass (LBM) and skeletal muscle phenotype. Our data indicate that training affects irisin biology in a LBM-dependent manner. However, no association was found between steady-state serum-irisin or training-associated changes in serum-irisin and alterations in body composition. FNDC5 expression was higher in m.Biceps brachii than in m.Vastus lateralis, with individual expression levels being closely correlated, suggesting a systemic mode of transcriptional regulation. In pre-biopsies, FNDC5 expression was correlated with proportions of aerobic muscle fibers, a relationship that disappeared in post-biopsies. No association was found between serum-thyroid hormones and FNDC5 expression or serum-irisin. CONCLUSION: No evidence was found for an effect of strength training on irisin biology in untrained women, though indications were found for a complex interrelationship between irisin, body mass composition and muscle phenotype. FNDC5 expression was closely associated with muscle fiber composition in untrained muscle.

Reliable determination of training-induced alterations in muscle fiber composition in human skeletal muscle using quantitative polymerase chain reaction.

Determination of muscle fiber composition in human skeletal muscle biopsies is often performed using immunohistochemistry, a method that tends to be both time consuming, technically challenging, and complicated by limited availability of tissue. Here, we introduce quantitative reverse transcriptase polymerase chain reaction (qRT-PCR)-based Gene-family profiling (GeneFam) of myosin heavy chain (MyHC) mRNA expression as a high-throughput, sensitive, and reliable alternative. We show that GeneFam and immunohistochemistry result in similar disclosures of alterations in muscle fiber composition in biopsies from musculus vastus lateralis and musculus biceps brachii of previously untrained young women after 12 weeks of progressive strength training. The adaptations were evident as (a) consistent increases in MyHC2A abundance; (b) consistent decreases in MyHC2X abundance; and (c) consistently stable MyHC1 abundance, and were not found using traditional reference gene-based qRT-PCR analyses. Furthermore, muscle fiber composition found using each of the two approaches was correlated with each other (r = 0.50, 0.74, and 0.78 for MyHC1, A, and X, respectively), suggesting that GeneFam may be suitable for ranking of individual muscle phenotype, particularly for MyHC2 fibers. In summary, GeneFam of MyHC mRNA resulted in reliable assessment of alterations in muscle fiber composition in skeletal muscle of previously untrained women after 12 weeks of strength training.

Model-derived dose rates per unit concentration of radon in air in a generic plant geometry.

A model for the derivation of dose rates per unit radon concentration in plants was developed in line with the activities of a Task Group of the International Commission on Radiological Protection (ICRP), aimed at developing more realistic dosimetry for non-human biota. The model considers interception of the unattached and attached fractions of the airborne radon daughters by plant stomata, diffusion of radon gas through stomata, permeation through the plant's epidermis and translocation of deposited activity to plant interior. The endpoint of the model is the derivation of dose conversion coefficients relative to radon gas concentration at ground level. The model predicts that the main contributor to dose is deposition of (214)Po α-activity on the plant surface and that diffusion of radon daughters through the stomata is of relatively minor importance; hence, daily variations have a small effect on total dose.

The relationship of retinal vessel diameter to changes in diabetic nephropathy structural variables in patients with type 1 diabetes.

AIMS/HYPOTHESIS: We examined whether retinal vessel diameter in persons with type 1 diabetes mellitus is associated with changes in subclinical anatomical and functional indicators of diabetic nephropathy. METHODS: Persons with type 1 diabetes mellitus had gradable fundus photographs and renal biopsy data at baseline and 5-year follow-up (n = 234). Retinal arteriolar and venular diameters were measured at baseline and follow-up. Central retinal arteriole equivalent (CRAE) and central retinal venule equivalent (CRVE) were computed. Baseline and 5-year follow-up renal structural variables were assessed by masked electron microscopic morphometric analyses from percutaneous renal biopsy specimens. Variables assessed included: mesangial fractional volume, glomerular basement membrane width, mesangial matrix fractional volume and glomerular basement membrane width composite glomerulopathy index. RESULTS: While controlling for other covariates, baseline CRAE was positively associated with change in the glomerulopathy index over the 5-year period. Change in CRAE was inversely related to a change in mesangial matrix fractional volume and abnormal mesangial matrix fractional volume, while change in CRVE was directly related to change in the volume fraction of cortex that was interstitium [Vv((Int/cortex))] over the 5-year period. Baseline CRAE or CRVE or changes in these diameters were not related to changes in other anatomical or functional renal endpoints. CONCLUSIONS/INTERPRETATION: Independently of other factors, baseline CRAE correlated with changes in glomerulopathy index, a composite measure of extracellular matrix accumulation in the mesangium and glomerular basement membrane. A narrowing of the CRAE was related to mesangial matrix accumulation. Changes in CRVE were related to changes in Vv((Int/cortex),) a measure of interstitial expansion in persons with type 1 diabetes mellitus.

A population-based evaluation of the seventh edition of the TNM system for lung cancer.

Our study describes the new seventh edition of the TNM system for lung cancer in a national population and its clinical implications. We classified 1,885 operated patients with lung cancer, reported to the Cancer Registry of Norway (Oslo, Norway) from 2001 to 2005, according to the sixth and the seventh edition of the TNM system. We compared survival differences adjusting for known prognostic factors. Furthermore, we evaluated the overall predictive ability of both editions using Harrell's concordance index. Survival curves by stage for each of the editions were similar; however, a better description of stage IIIB was observed in the seventh edition. Survival rates of T1b and T2a tumours were similar (log rank p = 0.94). The concordance index was 0.68 for both editions, indicating no overall difference in their predictive accuracy. In the seventh edition, 211 (29%) stage IB patients migrated to stage II and 161 (48%) patients migrated from stage IIB to IIA. Stage migrations could change the treatment for up to 326 (17.3%) of the study patients. The seventh edition did not improve the overall predictive ability of the TNM system; however, the new classification implies changes in treatment for nearly one-fifth of the cases. The implications of the seventh TNM edition for the outcomes of patients should be studied further.

Transportation of critically ill patients on extracorporeal membrane oxygenation.

Serious pulmonary and cardiac failure may be treated with extracorporeal membrane oxygenation (ECMO) when conventional treatment fails. In some severely ill patients, it may be necessary to initiate ECMO at the local hospital and, thereafter, transport the patient back to the ECMO center. The aim of this study was to evaluate our experiences with transportation of patients on ECMO. From Oct 1992 to Jan 2008 23, patients were transported on ECMO from local hospitals to Rikshospitalet. The study included seventeen patients with pulmonary failure and four patients with cardiac failure. All age groups were represented. Aircraft were used in 17 cases, ground vehicles in six. The times from decision until ECMO was established, the time from ECMO to departure from the local hospital and the transportation time were registered. All transportations were uneventful. After 10.3 +/-6.7 days, six patients died on ECMO and another patient died within 30 days. Mean ECMO time for those who died was 13.3 +/- 9.6 vs. 8.5 +/- 4.7 days for survivors, p=0.34. Seventeen patients were able to be successfully weaned from ECMO. Thirty day survival was 67%. The mean age for survivors was 15.3+/-18.3 (range 0-54.6) vs. 23.6 +/- 20.3 years (range 0-55.9) in fatal cases, p=0.41. The time from referral to initiating ECMO was a mean of 7.32 +/- 2.3 (3.0-12.0) hours for survivors vs. 7.88 +/- 3.0 (3.50-13.40) hours for non- survivors, p=0.76. The time from initiating ECMO to departure was 5.1 +/- 6.5 (0.58-23.75) hours in survivors vs. 9.1 +/- 6.8 (0.55-18.45) hours in non-survivors, p=0.18. Time from departure to arrival at Rikshospitalet was a mean of 3.2 (0.50-5.10) hours for survivors versus 2.5 (0.5-4.40) for non-survivors, p=0.41. This study shows that ECMO can be successfully established at local hospitals, using an experienced team, and that transportation of patients on ECMO can be performed safely and without technical difficulties. Survival for this group of patients did not differ from patients treated at the ECMO center.

Effectiveness of third-generation chemotherapy on the survival of patients with advanced non-small cell lung cancer in Norway: a national study.

BACKGROUND: To investigate whether the introduction of modern third-generation chemotherapy was associated with survival benefits in a national population of patients with advanced non-small cell lung cancer (ANSCLC) and to explore geographical and temporary variations in the utilisation of chemotherapy. METHODS: All patients with ANSCLC in the Cancer Registry of Norway during 1994-2005 were included. Using sales of vinorelbine as an indicator for chemotherapy, annual county utilisation rates were calculated. Survival before and after the general introduction of vinorelbine and associations between survival and variations in utilisation in counties were investigated. In a subgroup, the predictors of having received chemotherapy were explored. RESULTS: Of 24 875 registered patients with lung cancer, 13 757 had ANSCLC. The annual utilisation of the indicator drug in Norway increased from 3.7 to 184.2 g (1998-2005). Median survival increased from 149 to176 days (p<0.001). The adjusted hazard ratio (HR) for a diagnosis after the introduction was 0.93 (95% CI 0.88 to 0.99). County utilisation rates of vinorelbine (increments of 100 mg/1000 inhabitants) were inversely associated with the risk of death (HR 0.84, 95% CI 0.73 to 0.98). County of residence predicted chemotherapy utilisation with odds ratios in the range 0.13 (95% CI 0.1 to 0.19) to 1.04 (95% CI 0.64 to 1.69), a county with traditionally high utilisation as reference. CONCLUSION: Utilisation of third-generation chemotherapy was associated with slightly increased survival of patients with ANSCLC. Geographical and temporal differences in utilisation indicate variable quality of delivered care.

Anomalously high radon concentrations in dwellings located on permeable glacial sediments.

Indoor radon concentrations were measured in different seasons in 104 dwellings located on a highly permeable ice-marginal moraine in Kinsarvik, Western Norway. The measurements revealed the highest indoor radon levels ever detected in Norway and extreme variations in seasonal and short-term indoor radon levels. Annual average indoor radon concentrations up to 56 000 Bq m(-3) and a mean value of 4340 Bq m(-3) for the whole residential area are reported. By using the ICRP conversion factors to effective dose, these indoor radon values correspond to a total annual effective dose of 930 mSv and 72 mSv, respectively. By using the conversion as recommended by UNSCEAR, the effective doses would be about 50% higher. The indoor radon concentrations are found to be strongly influenced by thermally induced flows of radon-bearing soil air directed towards the upper part of the ice-marginal deposit in winter and towards the area of lowest elevation in summer. The pattern of seasonal variations observed suggests that in areas where thermal convection may occur, annual average indoor radon levels should be derived from measurements performed both in summer and in winter.

Prevalence of iron deficiency and anemia among healthy women of reproductive age in Bhaktapur, Nepal.

OBJECTIVE: To determine the prevalence of anemia and iron status as assessed by biochemical markers and to explore the associations between markers of iron status and iron intake. STUDY AREA AND POPULATION: Five hundred healthy women of reproductive age from the Bhaktapur district of Nepal were included in the study. METHODS: A cluster sampling procedure was applied for this cross-sectional study. Women without any ongoing infection aged 13-35 years were selected randomly from the population. We measured the plasma concentration of hemoglobin (Hb), ferritin and transferrin receptors. Dietary information was obtained by a food frequency questionnaire and two 24-h dietary recalls. RESULTS: The prevalence of anemia (Hb concentration <12 g/dl) was 12% (n=58). The prevalence of depleted iron stores (plasma ferritin <15 microg/l) was 20% (n=98) whereas the prevalence of iron deficiency anemia (anemia, depleted iron stores with elevated transferrin receptor i.e. >1.54 mg/l) was 6% (n=30). Seven percent (n=35) of women were having iron-deficient erythropoiesis (depleted iron stores and elevated transferrin receptor but normal Hb). Out of the 58 anemic women, 41 (71%) and 31 (53%) were also having elevated plasma transferrin receptor and depleted iron stores, respectively. Fifty-four percent of the women ate less than the recommended average intake of iron. The main foods contributing to dietary iron were rice, wheat flour and green and dry vegetables. CONCLUSIONS: The prevalence of anemia in our study was substantially lower than the national figure for non-pregnant women. Only about half of the women with anemia were also having depleted iron stores, suggesting that other causes of anemia may be prevalent in this population. SPONSORSHIP: Norwegian Universities Committee for Development, Research and Education (NUFU).

Survival after resection for primary lung cancer: a population based study of 3211 resected patients.

BACKGROUND: Very few population based results have been presented for survival after resection for lung cancer. The purpose of this study was to present long term survival after resection and to quantify prognostic factors for survival. METHODS: All lung cancer patients diagnosed in Norway in 1993-2002 were reported to the Cancer Registry of Norway (n = 19 582). A total of 3211 patients underwent surgical resection and were included for analysis. Supplementary information from hospitals (including co-morbidity data) was collected for patients diagnosed in 1993-8. Five year observed and relative survival was analysed for patients diagnosed and operated in 1993-9. Factors believed to influence survival were analysed by a Cox proportional hazard regression model. RESULTS: Five year relative survival in the period 1993-9 was 46.4% (n = 2144): 58.4% for stage I disease (n = 1375), 28.4% for stage II (n = 532), 15.1% for IIIa (n = 133), 24.1% for IIIb (n = 63), and 21.1% for stage IV disease (n = 41). The high survival in stage IIIb and IV was due to the contribution of multiple tumours. Cox regression analysis identified male sex, higher age, procedures other than upper and middle lobectomy, histologies such as adenocarcinoma and large cell carcinoma, surgery on the right side, infiltration of resection margins, and larger tumour size as non-favourable prognostic factors. CONCLUSIONS: Survival was favourable for resected patients in a population based group including subgroups such as elderly patients, those with advanced stage, small cell lung cancer, tumours with nodal invasion, and patients with multiple tumours. These results question the validity of the current TNM system for lung cancer with regard to tumour size and categorization of multiple tumours.

Long-term follow-up after primary repair of the anterior cruciate ligament: clinical and radiological evaluation 15-23 years postoperatively.

INTRODUCTION: We have previously reported results after 2-5 and 5-10 years follow-up of repair of acute anterior cruciate ligament (ACL) ruptures by suturing. Reports of results after more than 10 years are rare. MATERIALS AND METHODS: A total of 140 patients were operated on in the period 1975-1983 (age range 13-71 years, median 28 years) by the modified Palmer technique. Only 2 meniscus resections and 4 meniscectomies were performed at the primary operation; while 28 menisci were sutured. At follow-up,12 patients were dead. Eighteen patients (13%) underwent repeat operations for secondary instability. Of the remaining 110 patients, 81 appeared for follow-up. RESULTS: Only 6 secondary meniscus resections were performed, all in the group of 18 patients operated on again for instability. No secondary meniscus surgery was performed on the 81 patients who appeared for follow-up. The median Lysholm score was 88, and 58 of the 81 patients (71%) classified their total knee function as good or excellent. By KT-1000 testing, 33 (41%) patients had less than 3 mm anterior instability, 29 (36%) had 3-5 mm instability, and 17 (21%) had more than 5 mm. With 18 patients from the total of 128 living patients re-operated for instability, we estimate the rate of total failure of stability as 27%. Radiological osteoarthritis grade C was present in 8 operated and 2 control knees, while only 1 operated knee revealed osteoarthritis grade D. Thirty-four operated and 20 control knees had grade B. Osteoarthritis was correlated to more advanced age at injury, while correlation to function could not be proven. Radiographs were obtained of 61 patients at follow-up. CONCLUSIONS: Some 50% of patients had stable or slightly unstable knees, and 40% good or excellent function according to the Lysholm score. Re-operation for instability was more frequent in younger patients, while ostearthritis was more frequent in older patients. The rate of meniscus resection or extirpation was low. Open repair by suture is no longer recommended. Further research is indicated on the possible use of refixation of the ruptured ACL by arthroscopy.

Indoor gamma radiation and radon concentrations in a Norwegian carbonatite area.

Results of indoor gamma radiation and radon measurements in 95 wooden dwellings located in a Norwegian thorium-rich carbonatite area using thermoluminescent dosemeters and CR-39 alpha track detectors, respectively, are reported together with a thorough analysis of the indoor data with regard to geological factors. Slightly enhanced radium levels and thorium concentrations of several thousands Bq kg(-1) in the carbonatites were found to cause elevated indoor radon-222 levels and the highest indoor gamma dose rates ever reported from wooden houses in Norway. An arithmetic mean indoor gamma dose rate of 200 nGy h(-1) and a maximum of 620 nGy h(-1) were obtained for the group of dwellings located directly on the most thorium-rich bedrock.

The influence of geological factors on indoor radon concentrations in Norway.

Indoor radon levels in 1618 Norwegian dwellings located in different geological settings are compared with geological information. The results show a significant correlation between indoor radon levels and geological factors. Radium content and permeability of the building ground have been found to be useful indicators of indoor radon concentrations. Based on easily accessible geological data, an assessment of the radon potential of an area can be given. Areas of high radon risk in Norway include: (a) exposed bedrock with elevated levels of radium; and (b) highly permeable unconsolidated sediments derived from all rock types and moderately permeable sediments derived from rock types rich in radium. A comparison of indoor radon with house construction characteristics and ventilation habits suggests that radon concentrations in Norwegian dwellings are also influenced by ventilation system, aeration habits and floor level of the room where the measurements were carried out. The significant correlation between indoor radon levels and geological factors observed in the present investigation indicates that it is possible to outline areas of high radon risk in Norway based on geological information.

Rapid response car as a supplement to the helicopter in a physician-based HEMS system.

BACKGROUND: The purpose of this study was to describe the use of a rapid response car (RRC) as a supplement to the ambulance helicopter in a mixed urban/rural region in Norway. METHODS: Data from all the requested missions were collected from standard flight records. Operational factors, patient characteristics, primary diagnosis, treatment and modes of transport were registered and analyzed retrospectively. RESULTS: In 1999-2001, a total of 4777 requests were included in the study, resulting in the initiation of 3172 helicopter and 752 RRC missions. In the RRC missions, 224 patients received advanced medical treatment that would otherwise not have been provided. For 181 patients, the availability of the RRC was crucial for receiving the treatment of the helicopter emergency medical services (HEMS). The cost of equipping the base with the RRC increased the annual budget by less than one percent. CONCLUSION: The RRC was essential for solving missions in periods of non-flying conditions. The RRC increased the availability of the advanced prehospital life support offered by the HEMS in this region. Taking the modest increase in cost into consideration, it seems reasonable that this HEMS, covering mixed urban and rural areas, is equipped with such a vehicle.

The immune response to pneumococcal polysaccharide vaccine in zinc-depleted mice.

Zinc depletion affects several facets of the immune system and the resistance to infections. We assessed the effect of zinc deprivation on the immune response to the pneumococcal polysaccharide antigens in the commercially available Pneumovax pneumococcal vaccine. Young female BALB/c mice were fed diets with 2.7, 5.8 or 25 micro g of elemental zinc per mg diet. After six weeks of pair feeding, there were significant differences in the mean body weights between the feeding groups and we demonstrated a dose response of the zinc level in the diet on growth. The induced zinc deficiency had no discernible effect on the antipneumococcal polysaccharide immunoglobulin M (IgM) response following immunization with the pneumococcal vaccine. Although zinc depletion has a detrimental effect on the immune system, the murine T-cell-independent response to antigens such as those in the pneumococcal polysaccharide capsule does not seem to be affected.

Radon: a possible risk factor in multiple sclerosis.

Ecological studies in Norway, using a method for spatially moving bivariate correlation analysis, show that south of 65 degrees N, there are significant positive correlations (p < 0.01) for rates of multiple sclerosis (MS) versus contents of radon (Rn) in indoor air, and significant negative correlations for MS rates versus fallout of magnesium (Mg) and amounts of precipitation. Based on these data, we propose the hypothesis that the content of Rn in inhaled air is a risk factor in MS. The release of harmful Rn levels to the air may be influenced by (1) the levels of exchangeable Mg in soil, which may affect the soil content of the Rn precursor radium (Ra), and (2) the amounts of precipitation through its effects on soil moisture, which is one of the factors controlling Rn emanation from the soil. This hypothesis agrees with several of the known epidemiological characteristics of MS.

Pneumococcal pulmonary infection, septicaemia and survival in young zinc-depleted mice.

The aim of the present study was to explore whether mice fed a diet low in Zn (2.0 mg Zn/kg diet) for a relatively short period of time were more prone to severe Streptococcus pneumoniae infection than mice fed a normal diet (25 mg elemental Zn/kg). The Zn-deficient mice were compared with mice in two Zn-adequate control groups; one pair-fed and another with free access to the diet. After 2 weeks feeding, the mice were infected intranasally under anaesthesia with a suspension containing about 10(7) pneumococci. Clinical status was observed every day and blood samples were examined for S. pneumoniae every second day for a week. All infected mice examined carried the infecting strain intranasally. The survival time and time before positive blood culture were significantly shorter in the Zn-depleted group than in the pair-fed Zn-adequate group (hazard ratios 15.6 and 3.2, and respectively). At the end of the observation period, ten of the twelve mice in the Zn-deficient group were dead while one of twelve and two of twelve were dead in the two Zn-adequate control groups. This study shows that even acutely-induced Zn deficiency dramatically increases the risk of serious pneumococcal infection in mice.

Micronutrient deficiency in children.

Malnutrition increases morbidity and mortality and affects physical growth and development, some of these effects resulting from specific micronutrient deficiencies. While public health efforts must be targeted to improve dietary intakes in children through breast feeding and appropriate complementary feeding, there is a need for additional measures to increase the intake of certain micronutrients. Food-based approaches are regarded as the long-term strategy for improving nutrition, but for certain micronutrients, supplementation, be it to the general population or to high risk groups or as an adjunct to treatment must also be considered. Our understanding of the prevalence and consequences of iron, vitamin A and iodine deficiency in children and pregnant women has advanced considerably while there is still a need to generate more knowledge pertaining to many other micronutrients, including zinc, selenium and many of the B-vitamins. For iron and vitamin A, the challenge is to improve the delivery to target populations. For disease prevention and growth promotion, the need to deliver safe but effective amounts of micronutrients such as zinc to children and women of fertile age can be determined only after data on deficiency prevalence becomes available and the studies on mortality reduction following supplementation are completed. Individual or multiple micronutrients must be used as an adjunct to treatment of common infectious diseases and malnutrition only if the gains are substantial and the safety window sufficiently wide. The available data for zinc are promising with regard to the prevention of diarrhea and pneumonia. It should be emphasized that there must be no displacement of important treatment such as ORS in acute diarrhea by adjunct therapy such as zinc. Credible policy making requires description of not only the clinical effects but also the underlying biological mechanisms. As findings of experimental studies are not always feasible to extrapolate to humans, the biology of deficiency as well as excess of micronutrients in humans must continue to be investigated with vigour.