Environmental drivers of increased ecosystem respiration in a warming tundra

Arctic and alpine tundra ecosystems are large reservoirs of organic carbon1,2. Climate warming may stimulate ecosystem respiration and release carbon into the atmosphere3,4. The magnitude and persistency of this stimulation and the environmental mechanisms that drive its variation remain uncertain5-7. This hampers the accuracy of global land carbon-climate feedback projections7,8. Here we synthesize 136 datasets from 56 open-top chamber in situ warming experiments located at 28 arctic and alpine tundra sites which have been running for less than 1 year up to 25 years. We show that a mean rise of 1.4 °C [confidence interval (CI) 0.9-2.0 °C] in air and 0.4 °C [CI 0.2-0.7 °C] in soil temperature results in an increase in growing season ecosystem respiration by 30% [CI 22-38%] (n = 136). Our findings indicate that the stimulation of ecosystem respiration was due to increases in both plant-related and microbial respiration (n = 9) and continued for at least 25 years (n = 136). The magnitude of the warming effects on respiration was driven by variation in warming-induced changes in local soil conditions, that is, changes in total nitrogen concentration and pH and by context-dependent spatial variation in these conditions, in particular total nitrogen concentration and the carbon:nitrogen ratio. Tundra sites with stronger nitrogen limitations and sites in which warming had stimulated plant and microbial nutrient turnover seemed particularly sensitive in their respiration response to warming. The results highlight the importance of local soil conditions and warming-induced changes therein for future climatic impacts on respiration.

A palaeogenomic investigation of overharvest implications in an endemic wild reindeer subspecies

Overharvest can severely reduce the abundance and distribution of a species and thereby impact its genetic diversity and threaten its future viability. Overharvest remains an ongoing issue for Arctic mammals, which due to climate change now also confront one of the fastest changing environments on Earth. The high-arctic Svalbard reindeer (Rangifer tarandus platyrhynchus), endemic to Svalbard, experienced a harvest-induced demographic bottleneck that occurred during the 17-20th centuries. Here, we investigate changes in genetic diversity, population structure, and gene-specific differentiation during and after this overharvesting event. Using whole-genome shotgun sequencing, we generated the first ancient and historical nuclear (n = 11) and mitochondrial (n = 18) genomes from Svalbard reindeer (up to 4000 BP) and integrated these data with a large collection of modern genome sequences (n = 90) to infer temporal changes. We show that hunting resulted in major genetic changes and restructuring in reindeer populations. Near-extirpation followed by pronounced genetic drift has altered the allele frequencies of important genes contributing to diverse biological functions. Median heterozygosity was reduced by 26%, while the mitochondrial genetic diversity was reduced only to a limited extent, likely due to already low pre-harvest diversity and a complex post-harvest recolonization process. Such genomic erosion and genetic isolation of populations due to past anthropogenic disturbance will likely play a major role in metapopulation dynamics (i.e., extirpation, recolonization) under further climate change. Our results from a high-arctic case study therefore emphasize the need to understand the long-term interplay of past, current, and future stressors in wildlife conservation.

Ancient reindeer mitogenomes reveal island-hopping colonisation of the Arctic archipelagos

Climate warming at the end of the last glacial period had profound effects on the distribution of cold-adapted species. As their range shifted towards northern latitudes, they were able to colonise previously glaciated areas, including remote Arctic islands. However, there is still uncertainty about the routes and timing of colonisation. At the end of the last ice age, reindeer/caribou (Rangifer tarandus) expanded to the Holarctic region and colonised the archipelagos of Svalbard and Franz Josef Land. Earlier studies have proposed two possible colonisation routes, either from the Eurasian mainland or from Canada via Greenland. Here, we used 174 ancient, historical and modern mitogenomes to reconstruct the phylogeny of reindeer across its whole range and to infer the colonisation route of the Arctic islands. Our data shows a close affinity among Svalbard, Franz Josef Land and Novaya Zemlya reindeer. We also found tentative evidence for positive selection in the mitochondrial gene ND4, which is possibly associated with increased heat production. Our results thus support a colonisation of the Eurasian Arctic archipelagos from the Eurasian mainland and provide some insights into the evolutionary history and adaptation of the species to its High Arctic habitat.

Adaptation to the High-Arctic island environment despite long-term reduced genetic variation in Svalbard reindeer

Typically much smaller in number than their mainland counterparts, island populations are ideal systems to investigate genetic threats to small populations. The Svalbard reindeer (Rangifer tarandus platyrhynchus) is an endemic subspecies that colonized the Svalbard archipelago ca. 6,000-8,000 years ago and now shows numerous physiological and morphological adaptations to its arctic habitat. Here, we report a de-novo chromosome-level assembly for Svalbard reindeer and analyze 133 reindeer genomes spanning Svalbard and most of the species' Holarctic range, to examine the genomic consequences of long-term isolation and small population size in this insular subspecies. Empirical data, demographic reconstructions, and forward simulations show that long-term isolation and high inbreeding levels may have facilitated the reduction of highly deleterious-and to a lesser extent, moderately deleterious-variation. Our study indicates that long-term reduced genetic diversity did not preclude local adaptation to the High Arctic, suggesting that even severely bottlenecked populations can retain evolutionary potential.

Contrasting genomic consequences of anthropogenic reintroduction and natural recolonization in high-arctic wild reindeer

Anthropogenic reintroduction can supplement natural recolonization in reestablishing a species' distribution and abundance. However, both reintroductions and recolonizations can give rise to founder effects that reduce genetic diversity and increase inbreeding, potentially causing the accumulation of genetic load and reduced fitness. Most current populations of the endemic high-arctic Svalbard reindeer (Rangifer tarandus platyrhynchus) originate from recent reintroductions or recolonizations following regional extirpations due to past overharvesting. We investigated and compared the genomic consequences of these two paths to reestablishment using whole-genome shotgun sequencing of 100 Svalbard reindeer across their range. We found little admixture between reintroduced and natural populations. Two reintroduced populations, each founded by 12 individuals around four decades (i.e. 8 reindeer generations) ago, formed two distinct genetic clusters. Compared to the source population, these populations showed only small decreases in genome-wide heterozygosity and increases in inbreeding and lengths of runs of homozygosity. In contrast, the two naturally recolonized populations without admixture possessed much lower heterozygosity, higher inbreeding and longer runs of homozygosity, possibly caused by serial population founder effects and/or fewer or more genetically related founders than in the reintroduction events. Naturally recolonized populations can thus be more vulnerable to the accumulation of genetic load than reintroduced populations. This suggests that in some organisms even small-scale reintroduction programs based on genetically diverse source populations can be more effective than natural recolonization in establishing genetically diverse populations. These findings warrant particular attention in the conservation and management of populations and species threatened by habitat fragmentation and loss.

Hunting for ecological indicators: are large herbivore skeleton measures from harvest data useful proxies for monitoring?

Hunter-collected data and samples are used as indices of population performance, and monitoring programs often take advantage of such data as ecological indicators. Here, we establish the relationships between measures of skeleton size (lower jawbone length and hind-leg length) and autumn carcass mass of slaughtered individuals of known age and sex of the high Arctic and endemic Svalbard reindeer (Rangifer tarandus platyrhynchus). We assess these relationships using a long-term monitoring dataset derived from hunted or culled reindeer. The two skeleton measures were generally strongly correlated within age class. Both jaw length (R2 = 0.78) and hind-leg length (R2 = 0.74) represented good proxies of carcass mass. These relationships were primarily due to an age effect (i.e. due to growth) as the skeleton measures reached an asymptotic size at 4–6 years of age. Accordingly, strong positive correlations between skeleton measures and carcass mass were mainly evident at the young age classes (range r [0.45–0.84] for calves and yearlings). For the adults, these relationships weakened due to skeletal growth ceasing in mature animals causing increased variance in mass with age—potentially due to the expected substantial impacts of annual environmental fluctuations. As proxies for carcass mass, skeleton measurements should therefore be limited to young individuals. Although body mass is the ‘gold standard’ in monitoring large herbivores, our results indicate that skeleton measures collected by hunters only provide similar valuable information for young age classes, particularly calves and yearlings. In sum, jaw length and hind-leg length function as proxies identical to body mass when documenting the impacts of changing environmental conditions on important state variables for reindeer and other herbivores inhabiting highly variable environments.

The neglected season: Warmer autumns counteract harsher winters and promote population growth in Arctic reindeer

Arctic ungulates are experiencing the most rapid climate warming on Earth. While concerns have been raised that more frequent icing events may cause die-offs, and earlier springs may generate a trophic mismatch in phenology, the effects of warming autumns have been largely neglected. We used 25 years of individual-based data from a growing population of wild Svalbard reindeer, to test how warmer autumns enhance population growth. Delayed plant senescence had no effect, but a six-week delay in snow-onset (the observed data range) was estimated to increase late winter body mass by 10%. Because average late winter body mass explains 90% of the variation in population growth rates, such a delay in winter-onset would enable a population growth of r = 0.20, sufficient to counteract all but the most extreme icing events. This study provides novel mechanistic insights into the consequences of climate change for Arctic herbivores, highlighting the positive impact of warming autumns on population viability, offsetting the impacts of harsher winters. Thus, the future for Arctic herbivores facing climate change may be brighter than the prevailing view.

Oral semaglutide versus injectable glucagon-like peptide-1 receptor agonists: a cost of control analysis

Aims: The efficacy and safety of oral semaglutide, the first glucagon-like peptide-1 (GLP-1) receptor agonist developed for oral administration for the treatment of type 2 diabetes, was evaluated in the PIONEER clinical trial program, and a recently published network meta-analysis allowed comparison with further injectable GLP-1 receptor agonists. The present study aimed to assess the short-term cost- effectiveness of oral semaglutide 14 mg versus subcutaneous once-weekly dulaglutide 1.5 mg, once-weekly exenatide 2 mg, twice-daily exenatide 10 µg, once-daily liraglutide 1.8 mg, once-daily lixisenatide 20 µg, and once-weekly semaglutide 1 mg, in terms of the cost per patient achieving glycated hemoglobin (HbA1c) targets (cost of control).Materials and methods: Cost of control was calculated by dividing the annual treatment costs associated with an intervention by the proportion of patients achieving the treatment target with an intervention, with outcomes calculated for targets of HbA1c ≤6.5% and HbA1c <7.0% for all included GLP-1 receptor agonists. Annual treatment costs were accounted in 2019 United States dollars (USD), based on 2019 wholesale acquisition cost.Results: For the treatment target of HbA1c ≤6.5%, once-weekly semaglutide 1 mg and oral semaglutide 14 mg were associated with the lowest costs of control, at USD 15,430 and USD 17,383 per patient achieving target, respectively. Similarly, the cost of control was lowest with once-weekly semaglutide 1 mg at USD 12,627 per patient achieving target, followed by oral semaglutide 14 mg at USD 13,493 per patient achieving target for the target of HbA1c <7.0%. All other interventions were associated with higher cost of control values for both targets.Conclusions: Oral semaglutide 14 mg is likely to be cost-effective versus dulaglutide, exenatide (once weekly and twice daily), liraglutide, and lixisenatide in terms of bringing people with type 2 diabetes to glycemic control targets of HbA1c ≤6.5% and HbA1c <7.0% in the US.

Sea ice loss increases genetic isolation in a high Arctic ungulate metapopulation

Sea ice loss may have dramatic consequences for population connectivity, extinction-colonization dynamics, and even the persistence of Arctic species subject to climate change. This is of particular concern in face of additional anthropogenic stressors, such as overexploitation. In this study, we assess the population-genetic implications of diminishing sea ice cover in the endemic, high Arctic Svalbard reindeer (Rangifer tarandus platyrhynchus) by analyzing the interactive effects of landscape barriers and reintroductions (following harvest-induced extirpations) on their metapopulation genetic structure. We genotyped 411 wild reindeer from 25 sampling sites throughout the entire subspecies' range at 19 microsatellite loci. Bayesian clustering analysis showed a genetic structure composed of eight populations, of which two were admixed. Overall population genetic differentiation was high (mean F_ST  = 0.21). Genetic diversity was low (allelic richness [AR] = 2.07-2.58; observed heterozygosity = 0.23-0.43) and declined toward the outer distribution range, where populations showed significant levels of inbreeding. Coalescent estimates of effective population sizes and migration rates revealed strong evolutionary source-sink dynamics with the central population as the main source. The population genetic structure was best explained by a landscape genetics model combining strong isolation by glaciers and open water, and high connectivity by dispersal across winter sea ice. However, the observed patterns of natural isolation were strongly modified by the signature of past harvest-induced extirpations, subsequent reintroductions, and recent lack of sea ice. These results suggest that past and current anthropogenic drivers of metapopulation dynamics may have interactive effects on large-scale ecological and evolutionary processes. Continued loss of sea ice as a dispersal corridor within and between island systems is expected to increase the genetic isolation of populations, and thus threaten the evolutionary potential and persistence of Arctic wildlife.

The effects of intra-articular glucocorticoids and exercise on pain and synovitis assessed on static and dynamic magnetic resonance imaging in knee osteoarthritis: exploratory outcomes from a randomized controlled trial

OBJECTIVE

The aims of the present knee osteoarthritis (KOA)-study were to: (1) describe and compare the changes in magnetic resonance imaging (MRI)-measures of synovitis following an exercise program preceded by an intra-articular injection of either corticosteroid or isotonic saline and (2) investigate if any of the changes in patient reported outcome measures (PROMs) were associated with changes in MRI-measures of synovitis.

DESIGN

We performed a randomized, double-blinded, placebo-controlled clinical trial evaluating the effects of intra-articular corticosteroid vs placebo injections given before exercise therapy in KOA-patients. PROMs were assessed using the KOOS (knee injury and osteoarthritis outcome score). Synovitis was assessed on conventional non-contrast-enhanced, conventional contrast-enhanced (CE) and dynamic contrast-enhanced (DCE) MRI. PROMs and MRIs were obtained prior to the intra-articular injection, after termination of the exercise program (week 14-primary time point) and week 26.

RESULTS

Of 100 randomized participants (50 in each allocation group), 91 had complete MRI-data at baseline (63% female, mean age: 62 years, median Kellgren-Lawrence-grade: 3). There were no statistically significant differences between the two interventions in regards of changes in MRI-measures of synovitis at any time-point. At week 14, we found no statistical significant MRI-explanatory variables of either of the PROMs.

CONCLUSIONS

The present study does not justify the use of intra-articular corticosteroids over intra-articular saline when combined with an exercise program for reduction of synovitis in KOA. The improvement in pain and function following the intervention with intra-articular corticosteroids/saline and exercise could not be explained by a decrease in synovitis on MRI indicating other pain causing/relieving mechanisms in KOA.

Contrasting effects of summer and winter warming on body mass explain population dynamics in a food-limited Arctic herbivore

The cumulative effects of climate warming on herbivore vital rates and population dynamics are hard to predict, given that the expected effects differ between seasons. In the Arctic, warmer summers enhance plant growth which should lead to heavier and more fertile individuals in the autumn. Conversely, warm spells in winter with rainfall (rain-on-snow) can cause 'icing', restricting access to forage, resulting in starvation, lower survival and fecundity. As body condition is a 'barometer' of energy demands relative to energy intake, we explored the causes and consequences of variation in body mass of wild female Svalbard reindeer (Rangifer tarandus platyrhynchus) from 1994 to 2015, a period of marked climate warming. Late winter (April) body mass explained 88% of the between-year variation in population growth rate, because it strongly influenced reproductive loss, and hence subsequent fecundity (92%), as well as survival (94%) and recruitment (93%). Autumn (October) body mass affected ovulation rates but did not affect fecundity. April body mass showed no long-term trend (coefficient of variation, CV = 8.8%) and was higher following warm autumn (October) weather, reflecting delays in winter onset, but most strongly, and negatively, related to 'rain-on-snow' events. October body mass (CV = 2.5%) increased over the study due to higher plant productivity in the increasingly warm summers. Density-dependent mass change suggested competition for resources in both winter and summer but was less pronounced in recent years, despite an increasing population size. While continued climate warming is expected to increase the carrying capacity of the high Arctic tundra, it is also likely to cause more frequent icing events. Our analyses suggest that these contrasting effects may cause larger seasonal fluctuations in body mass and vital rates. Overall our findings provide an important 'missing' mechanistic link in the current understanding of the population biology of a keystone species in a rapidly warming Arctic.

Climate events synchronize the dynamics of a resident vertebrate community in the high Arctic

Recently accumulated evidence has documented a climate impact on the demography and dynamics of single species, yet the impact at the community level is poorly understood. Here, we show that in Svalbard in the high Arctic, extreme weather events synchronize population fluctuations across an entire community of resident vertebrate herbivores and cause lagged correlations with the secondary consumer, the arctic fox. This synchronization is mainly driven by heavy rain on snow that encapsulates the vegetation in ice and blocks winter forage availability for herbivores. Thus, indirect and bottom-up climate forcing drives the population dynamics across all overwintering vertebrates. Icing is predicted to become more frequent in the circumpolar Arctic and may therefore strongly affect terrestrial ecosystem characteristics.

Bacterial vaginosis in a cohort of Danish pregnant women: prevalence and relationship with preterm delivery, low birthweight and perinatal infections

OBJECTIVE

To determine the prevalence of bacterial vaginosis (BV) in the second trimester of pregnancy in a Danish population using the Schmidt criteria and to examine whether BV was associated with subsequent preterm delivery, low birthweight or perinatal infections.

DESIGN

Prospective cohort study.

SETTING

Department of Obstetrics and Gynaecology at a University Hospital, Denmark.

POPULATION

Three thousand five hundred and forty pregnant women aged 18 years or more.

METHODS

A smear from the vagina was obtained from all women, air-dried and stored for subsequent diagnosis of BV. After rehydration with isotonic saline, the smear was examined in a phase-contrast microscope at 400x, and the numbers of lactobacilli morphotypes and small bacterial morphotypes were counted. A score for BV was calculated according to the method described by Schmidt. The outcome of pregnancy from 20 weeks of gestation was examined in the 3262 singleton pregnant women who were included in this study before 20 weeks of gestation. The relationship between BV and adverse outcome of pregnancy was examined by univariate and multivariate analyses.

MAIN OUTCOME MEASURES

Prevalence of BV, preterm delivery (<37 weeks), low birthweight (<2500 g), preterm delivery of a low-birthweight infant and clinical chorioamnionitis.

RESULTS

The prevalence of BV was 16%, and the rate of preterm delivery was 5.2% in the study population of 3262 singleton pregnant women who were included before 20 weeks of gestation. Mean birthweight was significantly lower in infants of women with BV than in infants of women without BV (3408 versus 3511 g, P < 0.01). Univariate analyses showed that BV was marginally associated with preterm delivery but significantly associated with low birthweight, preterm delivery of a low birthweight infant, indicated preterm delivery and clinical chorioamnionitis. Multivariate analyses, which adjusted for previous miscarriage, previous preterm delivery, previous conisation, smoking, gestational diabetes, fetal death and preterm premature rupture of membranes, showed that BV was significantly associated with low birthweight (OR 1.95, 95% CI 1.3-2.9), preterm delivery of a low-birthweight infant (OR 2.5, 95% CI 1.6-3.9), indicated preterm delivery (OR 2.4, 95% CI 1.4-4.1) and clinical chorioamnionitis (OR 2.7, 95% CI 1.4-5.1).

CONCLUSIONS

The prevalence of BV determined using the Schmidt criteria in the early second trimester of pregnancy was similar to that found in similar studies. The presence of BV before 20 weeks of gestation was an independent risk factor for delivery of an infant with low birthweight, preterm delivery of a low-birthweight infant, indicated preterm delivery and clinical chorioamnionitis.

Perinatal complications in women with gestational diabetes mellitus

BACKGROUND

The aim of the study was to examine the outcome of the pregnancy and neonatal period in 1) women with gestational diabetes mellitus and non-diabetic pregnant women, and 2) in women with early and late diagnosis of gestational diabetes mellitus.

METHODS

Included were 327 women with gestational diabetes mellitus and 295 non-diabetic women, who were screened with a 75 g oral glucose tolerance test because of risk factors for gestational diabetes. Women with gestational diabetes mellitus were treated with low-caloric diet and insulin when appropriate, while women in the control group received routine antenatal care.

RESULTS

Gestational age at delivery was significantly lower in the group with gestational diabetes mellitus, both when considering all deliveries (39.1+/-1.7 weeks versus 39.8+/-2.0 weeks, p<0.05) and only those with spontaneous onset of labor (38.8+/-2.0 weeks versus 40.0+/-1.6 weeks, p<0.05). The frequency of macrosomia was increased, although not statistically significant (8% vs. 2%, p=0.07), and the rate of admission to the neonatal ward was significantly increased (18% vs. 9%, p<0.05) in the group with gestational diabetes. Women with early diagnosis of gestational diabetes mellitus had a significantly increased need for insulin treatment during pregnancy (36% vs. 9% p<0.05) and a significantly higher occurrence of diabetes mellitus at follow-up from two months until three years postpartum.

CONCLUSIONS

This study of women with gestational diabetes mellitus and non-diabetic pregnant women showed that gestational diabetes mellitus was associated with a significantly lower gestational age at delivery and an increased rate of admission to the neonatal ward. Women diagnosed with GDM before 20 weeks of gestation had an increased need for insulin treatment during pregnancy and a high risk of subsequent overt DM, compared with women diagnosed with GDM later in pregnancy.

Determination of zuclopenthixol and its main N-dealkylated metabolite in biological fluids using high-performance liquid chromatography with post-column photochemical derivatization and fluorescence detection

A highly sensitive high-performance liquid chromatographic (HPLC) method for the assay of cis-(Z)-clopenthixol (zuclopenthixol) in urine and plasma has been developed. Following solid-phase extraction, the samples are chromatographed using reversed-phase ion-pairing HPLC. After separation, the solutes, having a thioxanthene structure, are transformed on-line into thioxanthones in a photochemical reactor. The thioxanthones are highly fluorescent compounds, and therefore, low detection limits are obtained when using fluorescence detection. Detection limits for zuclopenthixol and its N-dealkylated metabolite, in plasma as well as in urine, using fluorescence detection with excitation at 260 nm and emission at 435 nm, were found to be 0.05 ng/ml and 0.2 ng/ml, respectively. The chromatographic system separates the cis-(Z)- and trans-(E)-isomers of clopenthixol from its main dealkylated metabolite. Furthermore, the chromatographic system is very suitable for study of the photochemical reaction, since the chloro-thioxanthone and thioxanthone are well separated from the isomers of clopenthixol.

Correlation between distal nephron enzyme activity, structure and function in rats during lithium and lithium plus neuroleptic treatment

The histochemical activities of nonspecific acid and alkaline phosphatases, NADH- and NADPH-tetrazolium reductases, alpha-glycerophosphate dehydrogenase, succinate dehydrogenase, isocitrate dehydrogenase, lactate dehydrogenase and glucose-6-phosphate dehydrogenase were investigated in kidneys from rats treated with lithium and lithium plus neuroleptics. During the first 8 weeks of lithium treatment the activity of NADH-tetrazolium reductase, succinate dehydrogenase and alpha-glycerophosphate dehydrogenase activity in the collecting ducts increased. The other enzymes did not change. After 8 weeks of treatment no further changes in enzyme activity occurred. Withdrawal of lithium caused normalization of enzyme activity after 8 weeks. A decrease in concentration ability was found in parallel with the increase in enzyme activities (p less than 0.001). The changes in enzyme activity were not significantly correlated to morphological changes in the collecting ducts. Treatment with neuroleptics alone caused no change in enzyme activity. During combined lithium plus neuroleptic treatment the enzyme activities changed in a similar way as during lithium therapy, but the changes were less pronounced. In parallel, a less pronounced decrease in concentration ability was found during this treatment.

Functional and structural changes in the rat kidney by long-term lithium treatment

The relation between functional and structural renal changes induced by lithium was studied in rats during long-term treatment and after withdrawal of lithium. Administration of LiCl in the diet for up to 21 weeks caused marked polyuria associated with a significant lowering of renal concentrating ability assessed by dehydration and vasopressin tests. Plasma creatinine and plasma urea were not significantly changed by the treatment. Upon withdrawal of lithium water intake and concentrating ability were normalized within 4--8 weeks. Lithium caused focal light microscopic changes in the distal convoluted tubule and the collecting duct, consisting of nuclear and cellular polymorphism and, after prolonged treatment, dilatation of tubular lumens with tubular cell atrophy. These changes appeared later than the concentrating defect and persisted when lithium was withdrawn after prolonged treatment. No significant correlation was found between the degree of tubular changes and water intake or concentrating ability. It is concluded that the reversible diabetes insipidus induced by lithium in rats cannot be explained directly by the light microscopical changes observed in the distal part of the nephron, although the structural changes may be secondary to the polyuric state induced by lithium.

Very-low-calorie diet in the treatment of massive obesity: preliminary experience

Twenty-two consecutive obese patients were given very-low-calorie diet (VLCD) in the form of a casein and lactose preparation dissolved in orange juice containing 43.0 g protein, 30.4 g carbohydrate and 1.1 g lipid in a total of 317 kcal (1.3 MJ) daily. VLCD was given intermittently in eight-week periods alternating with three-week periods of conventional diet (900-1200 kcal, 3.8-5.0 MJ) to ensure recuperation of lean body mass and to establish a therapy which may facilitate indefinite patient compliance. In case of persisting hunger, diethyl-propion was given in small doses. The median observation time was nine weeks (range 1-37 weeks). The median weight loss was 15.5 kg (range 3.8-39.2 kg), and the median overweight decreased from 85.5 per cent (range 43-135 per cent) to 61.0 per cent (range 19-100 per cent). Blood glucose and cholesterol fell significantly (P < 0.01), and no major side-effects were observed.