Age-period-cohort modelling of type 1 diabetes incidence rates among children included in the EURODIAB 25-year follow-up study

AIMS

Specific patterns in incidence may reveal environmental explanations for type 1 diabetes incidence. We aimed to study type 1 diabetes incidence in European childhood populations to assess whether an increase could be attributed to either period or cohort effects.

METHODS

Nineteen EURODIAB centres provided single year incidence data for ages 0-14 in the 25-year period 1989-2013. Case counts and person years were classified by age, period and cohort (APC) in 1-year classes. APC Poisson regression models of rates were fitted using restricted cubic splines for age, period and cohort per centre and sex. Joint models were fitted for all centres and sexes, to find a parsimonious model.

RESULTS

A total of 57,487 cases were included. In ten and seven of the 19 centres the APC models showed evidence of nonlinear cohort effects or period effects, respectively, in one or both sexes and indications of sex-specific age effects. Models showed a positive linear increase ranging from approximately 0.6 to 6.6%/year. Centres with low incidence rates showed the highest overall increase. A final joint model showed incidence peak at age 11.6 and 12.6 for girls and boys, respectively, and the rate-ratio was according to sex below 1 in ages 5-12.

CONCLUSION

There was reasonable evidence for similar age-specific type 1 diabetes incidence rates across the EURODIAB population and peaks at a younger age for girls than boys. Cohort effects showed nonlinearity but varied between centres and the model did not contribute convincingly to identification of environmental causes of the increase.

Visceral fat and metabolic inflammation: the portal theory revisited

Abdominal (central) obesity strongly correlates with (hepatic) insulin resistance and type 2 diabetes. Among several hypotheses that have been formulated, the 'portal theory' proposes that the liver is directly exposed to increasing amounts of free fatty acids and pro-inflammatory factors released from visceral fat into the portal vein of obese patients, promoting the development of hepatic insulin resistance and liver steatosis. Thus, visceral obesity may be particularly hazardous in the pathogenesis of insulin resistance and type 2 diabetes. Herein, we will critically review existing evidence for a potential contribution of portally drained free fatty acids and/or cytokines to the development of hepatic insulin resistance.

Extracorporeal membrane oxygenation for pandemic H1N1 2009 respiratory failure

BACKGROUND

Severe respiratory failure related to infection with the pandemic influenza A/H1N1 2009 virus is uncommon but possibly life-threatening. If, in spite of maximal conventional critical care, the patient's condition deteriorates, extracorporeal membrane oxygenation (ECMO) may be a life-saving procedure.

METHODS

An observational study approved by the local ethics committee was carried out. Data from all patients treated with ECMO at the ECMO Center Karolinska for influenza A/H1N1 2009-related severe respiratory failure were analyzed. The main outcome measure was survival three months after discharge from our department.

RESULTS

Between July 2009 and January 2010, 13 patients with H1N1 2009 respiratory failure were treated with ECMO. Twelve patients were cannulated for veno-venous ECMO at the referring hospital and transported to Stockholm. One patient was cannulated in our hospital for veno-arterial support. The median ratio of the arterial partial oxygen pressure to the fraction of inspired oxygen (P/F ratio: PaO2 /FiO2) before cannulation was 52.5 (interquartile range 38-60). Four patients were converted from veno-venous to veno-arterial ECMO because of right heart failure (three) or life-threatening cardiac arrhythmias (one). The median maximum oxygen consumption via ECMO was 251 ml/min (187-281 ml/min). Twelve patients were still alive three months after discharge; one patient died four days after discharge due to intracranial hemorrhage.

CONCLUSION

Patients treated with veno-venous or veno-arterial ECMO for H1N1 2009-related respiratory failure may have a favorable outcome. Contributing factors may include the possibility of transport on ECMO, conversion from veno-venous (v-v) or veno-arterial (v-a) ECMO if necessary, high-flow ECMO to meet oxygen requirements and active surgery when needed.

Toll-like receptor 2-deficient mice are protected from insulin resistance and beta cell dysfunction induced by a high-fat diet

AIMS/HYPOTHESIS

Inflammation contributes to both insulin resistance and pancreatic beta cell failure in human type 2 diabetes. Toll-like receptors (TLRs) are highly conserved pattern recognition receptors that coordinate the innate inflammatory response to numerous substances, including NEFAs. Here we investigated a potential contribution of TLR2 to the metabolic dysregulation induced by high-fat diet (HFD) feeding in mice.

METHODS

Male and female littermate Tlr2(+/+) and Tlr2(-/-) mice were analysed with respect to glucose tolerance, insulin sensitivity, insulin secretion and energy metabolism on chow and HFD. Adipose, liver, muscle and islet pathology and inflammation were examined using molecular approaches. Macrophages and dendritic immune cells, in addition to pancreatic islets were investigated in vitro with respect to NEFA-induced cytokine production.

RESULTS

While not showing any differences in glucose homeostasis on chow diet, both male and female Tlr2(-/-) mice were protected from the adverse effects of HFD compared with Tlr2(+/+) littermate controls. Female Tlr2(-/-) mice showed pronounced improvements in glucose tolerance, insulin sensitivity, and insulin secretion following 20 weeks of HFD feeding. These effects were associated with an increased capacity of Tlr2(-/-) mice to preferentially burn fat, combined with reduced tissue inflammation. Bone-marrow-derived dendritic cells and pancreatic islets from Tlr2(-/-) mice did not increase IL-1beta expression in response to a NEFA mixture, whereas Tlr2(+/+) control tissues did.

CONCLUSION/INTERPRETATION

These data suggest that TLR2 is a molecular link between increased dietary lipid intake and the regulation of glucose homeostasis, via regulation of energy substrate utilisation and tissue inflammation.

Response of interleukin-6 during euglycaemic and hyperglycaemic exercise in patients with type 1 diabetes mellitus

The aim of this randomized, single-blinded cross-over study was to investigate the response of interleukin-6 (IL-6) during moderate aerobic exercise in stable euglycaemia and hyperglycaemia in seven male patients with type 1 diabetes mellitus. IL-6 increased significantly over the entire study period in euglycaemia, but not in hyperglycaemia.

10-day hyperlipidemic clamp in cats: effects on insulin sensitivity, inflammation, and glucose metabolism-related genes

Obesity and hyperlipidemia are associated with impaired insulin sensitivity in human type 2 diabetes mellitus, possibly due to activation of a mild inflammatory response. Because obesity-induced insulin resistance predisposes cats to diabetes and because hyperlipidemia is a frequent concurrent finding, excess lipids may also impair insulin sensitivity in cats. Healthy cats (n=6) were infused with lipids (Lipovenoes 10%) for 10 days to clamp blood triglycerides at the approximate concentration of untreated feline diabetes (3-7 mmol/l). Controls received saline (n=5). On day 10, plasma adiponectin and proinflammatory markers were measured. Whole-body insulin sensitivity was calculated following an intravenous glucose tolerance test. Tissue mRNAs of glucose metabolism-related genes were quantified in subcutaneous and visceral fat, liver, and skeletal muscles. Accumulation of lipids was assessed in liver. At the termination of infusion, whole-body insulin sensitivity did not differ between groups. Compared to saline, cats infused with lipids had 50% higher plasma adiponectin and 2-3 times higher alpha(1)-acid glycoprotein and monocyte chemoattractant protein-1. Unexpectedly, lipid-infused cats had increased glucose transporter-4 (GLUT4) mRNA in the visceral fat, and increased peroxisome proliferative activated receptor-gamma2 (PPARgamma2) in subcutaneous fat; adiponectin expression was not affected in any tissue. Lipid-infused cats developed hepatic steatosis. Although hyperlipidemia induced systemic inflammation, whole-body insulin sensitivity was not impaired after 10 day infusion. Increased circulating adiponectin may have contributed to prevent insulin resistance, possibly by increasing GLUT4 and PPARgamma2 transcripts in fat depots.

Left ventricular mechanical dyssynchrony is load independent at rest and during endotoxaemia in a porcine model

AIM

In diseased or injured states, the left ventricle displays higher degrees of mechanical dyssynchrony. We aimed at assessing mechanical dyssynchrony ranges in health related to variation in load as well as during acute endotoxin-induced ventricular injury.

METHODS

In 16 juvenile anaesthetized pigs, a five-segment conductance catheter was placed in the left ventricle as well as a balloon-tipped catheter in the inferior vena cava. Mechanical dyssynchrony during systole, including dyssynchrony time in per cent during systole and internal flow fraction during systole, were measured at rest and during controlled pre-load reduction sequences, as well as during 3 h of endotoxin infusion (0.25 microg kg(-)1 h(-1)).

RESULTS

Systolic dyssynchrony and internal flow fraction did not change during the course of acute beat-to-beat pre-load alteration. Endotoxin-produced acute pulmonary hypertension by left ventricular dyssynchrony measures was not changed during the early peak of pulmonary hypertension. Endotoxin ventricular injury led to progressive increases in systolic mechanical segmental dyssynchrony (7.9 +/- 1.2-13.0 +/- 1.3%) and ventricular systolic internal flow fraction (7.1 +/- 2.4-16.6 +/- 2.8%), respectively for baseline and then at hour 3. There was no localization of dyssynchrony changes to segment or region in the ventricular long axis during endotoxin infusion.

CONCLUSION

These results suggest that systolic mechanical dyssynchrony measures may be load independent in health and during acute global ventricular injury by endotoxin. More study is needed to validate ranges in health and disease for parameters of mechanical dyssynchrony.

Basal lipolysis, not the degree of insulin resistance, differentiates large from small isolated adipocytes in high-fat fed mice

AIMS/HYPOTHESIS

Adipocytes in obesity are characterised by increased cell size and insulin resistance compared with adipocytes isolated from lean patients. However, it is not clear at present whether hypertrophy actually does drive adipocyte insulin resistance. Thus, the aim of the present study was to metabolically characterise small and large adipocytes isolated from epididymal fat pads of mice fed a high-fat diet (HFD).

METHODS

C57BL/6J mice were fed normal chow or HFD for 8 weeks. Adipocytes from epididymal fat pads were isolated by collagenase digestion and, in HFD-fed mice, separated into two fractions according to their size by filtration through a nylon mesh. Viability was assessed by lactate dehydrogenase and 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium assays. Basal and insulin-stimulated D-[U-(14)C]glucose incorporation and lipolysis were measured. Protein levels and mRNA expression were determined by western blot and real-time RT-PCR, respectively.

RESULTS

Insulin-stimulated D-[U-(14)C]glucose incorporation into adipocytes isolated from HFD-fed mice was reduced by 50% compared with adipocytes from chow-fed mice. However, it was similar between small (average diameter 60.9 +/- 3.1 microm) and large (average diameter 83.0 +/- 6.6 microm) adipocytes. Similarly, insulin-stimulated phosphorylation of protein kinase B and AS160 were reduced to the same extent in small and large adipocytes isolated from HFD-mice. In addition, insulin failed to inhibit lipolysis in both adipocyte fractions, whereas it decreased lipolysis by 30% in adipocytes of chow-fed mice. In contrast, large and small adipocytes differed in basal lipolysis rate, which was twofold higher in the larger cells. The latter finding was associated with higher mRNA expression levels of Atgl (also known as Pnpla2) and Hsl (also known as Lipe) in larger adipocytes. Viability was not different between small and large adipocytes.

CONCLUSIONS/INTERPRETATION

Rate of basal lipolysis but not insulin responsiveness is different between small and large adipocytes isolated from epididymal fat pads of HFD-fed mice.

Cardiac effects of endothelin receptor antagonism in endotoxemic pigs

Myocardial depression in sepsis is frequently encountered clinically and contributes to morbidity and mortality. Increased plasma levels of endothelin-1 (ET-1) have been described in septic shock, and previous reports have shown beneficial effects on cardiovascular performance and survival in septic models using ET receptor antagonists. The aim of the current study was to investigate specific cardiac effects of ET receptor antagonism in endotoxicosis. Sixteen domestic pigs were anesthetized and subjected to endotoxin for 5 h. Eight of these pigs were given tezosentan (dual ET receptor antagonist) after 3 h. Cardiac effects were evaluated using the left ventricular (LV) pressure-volume relationship. Endotoxin was not associated with any effects on parameters of LV contractile function [end-systolic elastance (Ees), preload recruitable stroke work (PRSW), powermax/end-diastolic volume (PWRmax/EDV) and dP/d tmax/end-diastolic volume (dP/d tmax/EDV)] but with impairments in isovolumic relaxation (time constant for pressure decay, tau) and mechanical efficiency. Tezosentan administration decreased Ees, PWRmax/EDV, and dP/d tmax/EDV, while improving tau and LV stiffness. Thus, dual ET receptor antagonism was associated with a decline in contractile function but, in contrast, improved diastolic function. Positive hemodynamic effects from ET receptor antagonism in acute endotoxemia may be due to changes in cardiac load and enhanced diastolic function rather than improved contractile function.

Improved glucose tolerance in mice receiving intraperitoneal transplantation of normal fat tissue

AIMS/HYPOTHESIS

The association between increased (visceral) fat mass, insulin resistance and type 2 diabetes mellitus is well known. Yet, it is unclear whether the mere increase in intra-abdominal fat mass, or rather functional alterations in fat tissue in obesity contribute to the development of insulin resistance in obese patients. Here we attempted to isolate the metabolic effect of increased fat mass by fat tissue transplantation.

METHODS

Epididymal fat pads were removed from male C57Bl6/J mice and transplanted intraperitoneally into male littermates (recipients), increasing the combined perigonadal fat mass by 50% (p < 0.005). At 4 and 8 weeks post-transplantation, glucose and insulin tolerance tests were performed, and insulin, NEFA and adipokines measured.

RESULTS

Circulating levels of NEFA, adiponectin and leptin were not significantly different between transplanted and sham-operated control mice, while results of the postprandial insulin tolerance test were similar between the two groups. In contrast, under fasting conditions, the mere increase in intra-abdominal fat mass resulted in decreased plasma glucose levels (6.9 +/- 0.4 vs 8.1 +/- 0.3 mmol/l, p = 0.03) and a approximately 20% lower AUC in the glucose tolerance test (p = 0.02) in transplanted mice. Homeostasis model assessment of insulin resistance (HOMA-IR) was 4.1 +/- 0.4 in transplanted mice (vs 6.2 +/- 0.7 in sham-operated controls) (p = 0.02), suggesting improved insulin sensitivity. Linear regression modelling revealed that while total body weight positively correlated, as expected, with HOMA-IR (beta: 0.728, p = 0.006), higher transplanted fat mass correlated with lower HOMA-IR (beta: -0.505, p = 0.031).

CONCLUSIONS/INTERPRETATION

Increasing intra-abdominal fat mass by transplantation of fat from normal mice improved, rather than impaired, fasting glucose tolerance and insulin sensitivity, achieving an effect opposite to the expected metabolic consequence of increased visceral fat in obesity.

WNT4 deficiency--a clinical phenotype distinct from the classic Mayer-Rokitansky-Kuster-Hauser syndrome: a case report

The pathways leading to female sexual determination in mammals are incompletely defined. Loss-of-function mutations in the WNT4 gene appear to cause developmental abnormalities of sexual differentiation in women and mice. We recruited six patients with different degrees of Müllerian abnormalities, with or without renal aberrations and a normal female 46,XX karyotype. A clear androgen excess was found only in one patient. This 19-year-old woman was affected by primary amenorrhoea, absence of Müllerian ducts derivatives, clinical (acne and hirsutism) and biochemical (repeatedly high levels of testosterone) signs of androgen excess. Direct sequencing of her WNT4 gene followed by functional studies in human ovarian cells (OVCAR3) was performed. This patient carried the novel R83C loss-of-function dominant negative mutation in her WNT4, confirming the role of WNT4 in the development and maintenance of the female phenotype in women. Our study can also help refine the phenotype of WNT4 deficiency in humans. In fact, it appears that at least in this limited casuistic small group of patients, the absence of a uterus (and not other Müllerian abnormalities) and the androgen excess are the pathognomonic signs of WNT4 defects, suggesting that this might be a clinical entity distinct from the classic Mayer-Rokitansky-Kuster-Hauser syndrome.

Positive inotropic and negative lusitropic effects of endothelin receptor agonism in vivo

The endothelin (ET) system is involved in the regulation of myocardial function in health as well as in several diseases, such as congestive heart failure, myocardial infarction, and septic myocardial depression. Conflicting results have been reported regarding the acute contractile properties of ET-1. We therefore investigated the effects of intracoronary infusions of ET-1 and of the selective ETBreceptor-selective agonist sarafotoxin 6c with increasing doses in anesthetized pigs. Myocardial effects were measured through analysis of the left ventricular pressure-volume relationship. ET-1 elicited increases in the myocardial contractile status (end-systolic elastance value of 0.94 ± 0.11 to 1.48 ± 0.23 and preload recruitable stroke work value of 68.7 ± 4.7 to 83.4 ± 7.2) that appear to be mediated through ETAreceptors, whereas impairment in left ventricular isovolumic relaxation (τ = 41.5 ± 1.4 to 58.1 ± 5.0 and t1/2= 23.0 ± 0.7 to 30.9 ± 2.6, where τ is the time constant for pressure decay and t1/2is the half-time for pressure decay) was ETBreceptor dependent. In addition, intravenous administration of ET-1 impaired ventricular relaxation but had no effect on contractility. Intracoronary sarafotoxin 6c administration caused impairments in left ventricular relaxation (τ from 43.3 ± 1.8 to 54.4 ± 3.4) as well as coronary vasoconstriction. In conclusion, ET-1 elicits positive inotropic and negative lusitropic myocardial effects in a pig model, possibly resulting from ETAand ETBreceptor activation, respectively.

Troglitazone causes acute mitochondrial membrane depolarisation and an AMPK-mediated increase in glucose phosphorylation in muscle cells

AIMS/HYPOTHESIS

Troglitazone was the first thiazolidinedione (TZD) approved for clinical use, exerting hypoglycaemic effects related to its action as a ligand of the peroxisome proliferator-activated receptor gamma receptor in adipocytes. However, emerging evidence suggests that mitochondrial function may be affected by troglitazone, and that skeletal muscle cells acutely respond to troglitazone by enhancing glucose uptake. The aim of the present study was to determine the cellular mechanisms by which troglitazone acutely stimulates glucose utilisation in skeletal muscle cells.

METHODS

L6 cells overexpressing GLUT4myc were incubated with troglitazone. Glucose uptake, transport and phosphorylation as well as AMP-activated protein kinase (AMPK) signalling and insulin signalling were examined. Changes in mitochondrial membrane potential were measured using the J-aggregate-forming dye JC-1. AMPK signalling was interfered with using AMPK alpha1/alpha2 siRNA.

RESULTS

Troglitazone acutely (in 10 min) reduced the mitochondrial membrane potential in L6GLUT4myc myotubes and robustly stimulated AMPK activity. Following 30 min of incubation with troglitazone or insulin, 2-deoxyglucose uptake was stimulated 1.5- and 2.1-fold respectively, and in cells treated with troglitazone, a 1.8-fold increase in the 2-deoxyglucose-6-phosphate:2-deoxyglucose ratio was observed. Moreover, contrary to insulin, troglitazone did not significantly stimulate 3-O-methylglucose uptake. Unlike insulin, troglitazone did not increase surface GLUT4myc content and did not increase IRS1-associated phosphatidylinositol 3-kinase activity or Akt phosphorylation on T308 and S473. Interestingly, interfering with troglitazone-induced activation of AMPK by decreasing the expression of the enzyme using siRNA inhibited the stimulation of 2-deoxyglucose uptake by the TZD.

CONCLUSIONS/INTERPRETATION

We propose that troglitazone acutely increases glucose flux in muscle via an AMPK-mediated increase in glucose phosphorylation.

Indinavir uncovers different contributions of GLUT4 and GLUT1 towards glucose uptake in muscle and fat cells and tissues

AIMS/HYPOTHESIS

Insulin-dependent glucose influx in skeletal muscle and adipocytes is believed to rely largely on GLUT4, but this has not been confirmed directly. We assessed the relative functional contribution of GLUT4 in experimental models of skeletal muscle and adipocytes using the HIV-1 protease inhibitor indinavir.

METHODS

Indinavir (up to 100 micro mol/l) was added to the glucose transport solution after insulin stimulation of wild-type L6 muscle cells, L6 cells over-expressing either GLUT4myc or GLUT1myc, 3T3-L1 adipocytes, isolated mouse brown or white adipocytes, and isolated mouse muscle preparations.

RESULTS

100 micro mol/l indinavir inhibited 80% of both basal and insulin-stimulated 2-deoxyglucose uptake in L6GLUT4myc myotubes and myoblasts, but only 25% in L6GLUT1myc cells. Cell-surface density of glucose transporters was not affected. In isolated soleus and extensor digitorum longus muscles, primary white and brown adipocytes, insulin-stimulated glucose uptake was inhibited 70 to 80% by indinavir. The effect of indinavir on glucose uptake was variable in 3T3-L1 adipocytes, averaging 45% and 67% inhibition of basal and maximally insulin-stimulated glucose uptake, respectively. In this cell, fractional inhibition of glucose uptake by indinavir correlated positively with the fold-stimulation of glucose uptake by insulin, and was higher with sub-maximal insulin concentrations. The latter finding coincided with an increase only in GLUT4, but not GLUT1, in plasma membrane lawns.

CONCLUSION/INTERPRETATION

Indinavir is a useful tool to assess different functional contributions of GLUT4 to glucose uptake in common models of skeletal muscle and adipocytes.

Comparison of gravimetric and a double-indicator dilution technique for assessment of extra-vascular lung water in endotoxaemia

OBJECTIVE

To compare a molecular double-indicator dilution technique with the gravimetrical reference method for measurement of extra-vascular lung water in porcine endotoxin shock.

DESIGN

Open comparative experimental study.

SETTING

Animal research laboratory.

MEASUREMENTS AND RESULTS

In fourteen anaesthetised, mechanically ventilated landrace pigs, central and pulmonary haemodynamics as well as pulmonary gas exchange were measured. Extra-vascular lung water was quantitated gravimetrically as well as with a molecular double indicator dilution technique. Eight of these animals were subjected to endotoxaemia, the rest serving as sham controls. No difference in extra-vascular lung water was observed between the two methods in sham animals. Furthermore, extra-vascular lung water assessed with the molecular double-indicator dilution technique at the initiation of endotoxin infusion did not differ significantly from the corresponding values for sham animals. Endotoxaemia induced a hypodynamic shock with concurrent pulmonary hypertension and a pronounced deterioration in gas exchange. No increase in extra-vascular lung water was detected with the molecular double-indicator dilution technique in response to endotoxin, whereas this parameter was significantly higher when assessed with the gravimetric method.

CONCLUSION

The molecular double-indicator dilution technique showed similar results as the gravimetrical method for assessment of extra-vascular lung water in non-endotoxaemic conditions. However, during endotoxin-induced lung injury the molecular double indicator dilution technique failed to detect the significant increase in extra-vascular lung water as measured by the gravimetric method. These data suggest that the molecular double indicator dilution technique may be of limited value during sepsis-induced lung injury.

High leptin levels acutely inhibit insulin-stimulated glucose uptake without affecting glucose transporter 4 translocation in l6 rat skeletal muscle cells

Obesity is a major risk factor for the development of insulin resistance, characterized by impaired stimulation of glucose disposal into muscle. The mechanisms underlying insulin resistance are unknown. Here we examine the direct effect of leptin, the product of the obesity gene, on insulin-stimulated glucose uptake in cultured rat skeletal muscle cells. Preincubation of L6 myotubes with leptin (2 or 100 nM, 30 min) had no effect on basal glucose uptake but reduced insulin-stimulated glucose uptake. However, leptin had no effect on the insulin-induced gain in myc-tagged glucose transporter 4 (GLUT4) appearance at the cell surface of L6 myotubes. Preincubation of cells with leptin also had no effect on insulin-stimulated tyrosine phosphorylation of insulin receptor, IRS-1 and IRS-2, phosphatidylinositol 3-kinase activity, or Akt phosphorylation. We have previously shown that insulin regulates glucose uptake via a signaling pathway sensitive to inhibitors of p38 MAP kinase. Here, leptin pretreatment reduced the extent of insulin-stimulated p38 MAP kinase phosphorylation and phosphorylation of cAMP response element binder, a downstream effector of p38 MAP kinase. These results show that high leptin levels can directly reduce insulin-stimulated glucose uptake in L6 muscle cells despite normal GLUT4 translocation. The mechanism of this effect could involve inhibition of insulin-stimulated p38 MAP kinase and GLUT4 activation.

Effects of levosimendan, a novel inotropic calcium-sensitizing drug, in experimental septic shock

OBJECTIVE

Levosimendan is a novel inodilator that improves cardiac contractility by sensitizing troponin C to calcium. This drug has proved to be effective in treating advanced congestive heart failure but has not been evaluated in septic settings. The purpose of the present study was to study the effects of this drug in a porcine model of endotoxemia.

DESIGN

Prospective experimental study.

SUBJECTS

Fourteen landrace pigs.

INTERVENTIONS

All animals were anesthetized and catheterized for measurement of central and pulmonary hemodynamics. Ultrasonic flow probes were placed around the renal artery and portal vein to measure blood flow. A tonometer was placed in the ileum to measure mucosal pH. Levosimendan was given to six animals as a bolus (200 microg x kg(-1)) followed by a continuous infusion (200 microg x kg(-1) x hr(-1)). Thirty minutes after onset of levosimendan treatment, all animals received endotoxin (20 microg x kg(-1) x hr(-1) for 3 hrs).

MEASUREMENTS AND MAIN RESULTS

At baseline, levosimendan induced a systemic vasodilation with a reduction in blood pressure and an increase in heart rate. A tendency to an increase in cardiac index did not reach statistical significance (p =.055). Cardiac index and systemic oxygen delivery were markedly improved in the levosimendan group during endotoxemia. Systemic vascular resistance and blood pressure were reduced in the levosimendan group. The latter parameter, however, was only different from the control group during the initial phase of endotoxin shock but not at the late, most pronounced phase of shock. Levosimendan also efficiently attenuated endotoxin-induced pulmonary hypertension. Portal venous blood flow and gut oxygen delivery were improved, but no concomitant reduction in endotoxin-induced intestinal mucosal acidosis was observed. Renal blood flow was unaffected, as was the endotoxin-induced increase in plasma endothelin-1-like immunoreactivity. These findings support previous reports of calcium desensitization as a potential component in septic myocardial depression. Furthermore, the vasodilatory properties of this drug were well tolerated in the current model of hypodynamic endotoxin shock, and they may have contributed to improved regional blood flow as seen in the gut as well as improved systemic perfusion by means of reduced biventricular afterload.

CONCLUSION

Pretreatment with levosimendan in pigs subjected to endotoxin shock improved cardiac output and systemic and gut oxygen delivery. In addition, pulmonary hypertension largely was attenuated without any adverse effects on gas exchange. These results are promising in several aspects, but the role of levosimendan in the treating circulatory failure in sepsis remains to be established.

Central diabetes insipidus as the first manifestation of neurosarcoidosis in a 10-year-old girl

Central diabetes insipidus with thickening of the pituitary stalk has been demonstrated in adults with Langerhans cell histiocytosis (LCH), tuberculosis or sarcoidosis, and in children with LCH. We present a 10.5-year-old girl with central diabetes insipidus. Magnetic resonance imaging (MRI) revealed thickening of the central part of the pituitary stalk and multiple hyperintense lesions in the frontal white matter on T(2)-weighted images. Laboratory findings were normal except for an elevated serum angiotensin-converting enzyme (ACE) level. The MRI findings together with the elevated serum ACE level highly suggest the diagnosis of sarcoidosis. We conclude that central diabetes insipidus can be the first clinical manifestation of sarcoidosis in children.

The antihyperglycemic drug alpha-lipoic acid stimulates glucose uptake via both GLUT4 translocation and GLUT4 activation: potential role of p38 mitogen-activated protein kinase in GLUT4 activation

The cofactor of mitochondrial dehydrogenase complexes and potent antioxidant alpha-lipoic acid has been shown to lower blood glucose in diabetic animals. alpha-Lipoic acid enhances glucose uptake and GLUT1 and GLUT4 translocation in 3T3-L1 adipocytes and L6 myotubes, mimicking insulin action. In both cell types, insulin-stimulated glucose uptake is reduced by inhibitors of p38 mitogen-activated protein kinase (MAPK). Here we explore the effect of alpha-lipoic acid on p38 MAPK, phosphatidylinositol (PI) 3-kinase, and Akt1 in L6 myotubes. alpha-Lipoic acid (2.5 mmol/l) increased PI 3-kinase activity (31-fold) and Akt1 (4.9-fold). Both activities were inhibited by 100 nmol/l wortmannin. alpha-Lipoic acid also stimulated p38 MAPK phosphorylation by twofold within 10 min. The phosphorylation persisted for at least 30 min. Like insulin, alpha-lipoic acid increased the kinase activity of the alpha (2.8-fold) and beta (2.1-fold) isoforms of p38 MAPK, measured by an in vitro kinase assay. Treating cells with 10 micromol/l of the p38 MAPK inhibitors SB202190 or SB203580 reduced the alpha-lipoic acid-induced stimulation of glucose uptake by 66 and 55%, respectively. In contrast, SB202474, a structural analog that does not inhibit p38 MAPK, was without effect on glucose uptake. In contrast to 2-deoxyglucose uptake, translocation of GLUT4myc to the cell surface by either alpha-lipoic acid or insulin was unaffected by 20 micromol/l of SB202190 or SB203580. The results suggest that inhibition of 2-deoxyglucose uptake in response to alpha-lipoic acid by inhibitors of p38 MAPK is independent of an effect on GLUT4 translocation. Instead, it is likely that regulation of transporter activity is sensitive to these inhibitors.

Selection of a hospital for a transfer: the roles of patients, families, physicians and payers

OBJECTIVE

This study investigates the reasons for hospital transfers and the role patients, their families, physicians, and payers play in the choice of a referral center.

DATA SOURCES

A thirty-three item questionnaire and clinical data from the hospital's discharge database.

STUDY DESIGN

A study of all 307 hospital transfer patients admitted between November 9 and December 3, 1993 was conducted to understand the factors contributing to the increase in transfers and the reasons patients were sent to CCH. Data on the transfer decision were collected by interviewing patients 48 hours after admittance to the hospital or by telephone if they were discharged before an interview could be completed. Two hundred and sixty-two (85%) patients were interviewed.

PRINCIPLE FINDINGS

(1) Almost 58% of transfers were patient-initiated or -influenced; the remainder were physician- (38%) or payer-directed (4%); (2) More than 78% of the patients identified lack of clinical expertise/technology at originating hospital as the main reason for transferring. Other reasons included: established CCH patient status (43%), CCH marketing (31%), and concerns regarding quality of care at originating hospital (10%). Financial and quality dumping were not identified as reasons for the transfer. New patients to CCH were more likely to indicate that marketing and lack of clinical resources at originating hospital were reasons for selecting CCH than previous patients.

CONCLUSIONS

Patients significantly influenced the transfer decision and the transfer decision-making process can be influenced by marketing. The opinions of the consumer should not be underestimated, especially by those seeking non-marketing solutions to health care reform.

The business of palliative medicine: management metrics for an acute-care inpatient unit

For any palliative medicine inpatient unit to be economically viable, certain management metrics need to be followed. Palliative medicine can provide both a compassionate and economical service within the current acute inpatient hospital environment. In this article, we will review the administrative and financial factors we have identified that influence the business of acute palliative medicine.

Echocardiography, color-coded Doppler imaging, and abdominal sonography, a non-invasive method for investigation of heart and aortic morphology and function in female gottingen minipigs: method and reference values for M-mode, B-mode, and flow parameters

OBJECTIVE

The aim of the study reported here was to set up a method for echocardiography (EC) and abdominal sonography and to obtain EC reference values for left ventricular (LV) morphology and function and sonographic abdominal aortic morphology, function, and flow values in conscious, unsedated Gottingen minipigs.

METHODS

Applying a standardized investigation procedure, the following parameters were measured by use of M-mode EC, color-coded Doppler imaging, and B-mode sonography, or were calculated, in 58 female minipigs: LV end-diastolic and end-systolic diameter, interventricular septum thickness, LV caudal wall thickness, LV end-diastolic volume and end-systolic volume, fractional shortening, ejection fraction, and percentage of thickening of interventricular septum and LV caudal wall. In addition, morphology, pulsatility, flow values, and flow patterns in the abdominal aorta were recorded or calculated during abdominal sonography and color-coded Doppler imaging.

RESULTS

Variable EC values were obtained due to individual variations of motor activity. Variation could be reduced by accustoming the animals to a standardized investigation procedure. Reference values could be obtained for EC, partially indicating clear correlation with body weight. Color-coded Doppler and Doppler spectra did not indicate flow disturbances in large arterial abdominal vessels.

CONCLUSIONS

Results indicate that handling during EC and sonography can cause discomfort in unsedated minipigs that may interfere with recording of valid reference values for functional cardiac parameters in young animals. Accustoming the animals to a standardized investigation procedure reduces stress to a satisfactory level and enables data recording. Thus the minipig is considered suitable for assessment of cardiovascular parameters in experimental or toxicologic studies.

Penoscrotal hypospadias and coarctation of the aorta with mixed gonadal dysgenesis

A 45,X/46,Xidic(Y)(q11.2) mosaicism was found in a 4-year-old boy. The clinical appearance was characterized by bilateral cryptorchidism, penoscrotal hypospadias, short penis, and coarctation of the aorta. The latter is the only abnormality also seen in Turner syndrome. A biopsy of the gonads revealed normal prepubertal testicular tissue. A chromosome analysis in all boys with penoscrotal, scrotal, or perineal hypospadias and a thorough examination of the heart in children with 45,X/46,XY mosaicism are recommended.

Mutational analysis of the DNA mismatch repair gene hMLH1 in myeloid leukaemias

Mutations of the DNA mismatch repair (MMR) gene hMLH1 have recently been linked to the development of some hereditary and sporadic cancers which frequently display widespread microsatellite instability (MSI). Conflicting results regarding the extent of MSI in myeloid leukaemias prompted us to perform mutational analysis of all 19 exons of the hMLH1 gene by polymerase chain reaction-single-stranded conformation polymorphism (PCR-SSCP) and sequence analysis in a total of 133 patients with acute and chronic myeloid leukaemia. Apart from one exonic and one intronic polymorphism, no mutations were detected in any of the samples indicating that the major MMR gene hMLH1 is not involved in the pathogenesis or progression of myeloid malignancies.

Group G streptococcus sacroilitis with sepsis in a 15-y-old adolescent

Group G streptococci cause invasive infections of different tissues. Most infected patients have underlying diseases and are of adult age. Invasive group G streptococcal infections rarely occur in childhood and adolescence. A 15-y-old boy with a beta-haemolytic group G streptococcus sacroiliitis, sepsis and secondary pulmonary manifestations resembling an acute respiratory distress syndrome is described.

Ten-year follow-up in a boy with Leydig cell tumor after selective surgery

In a 4(8)/12-year-old boy with precocious puberty and an enlarged right testis, a Leydig cell tumor was diagnosed. Surgical exploration revealed an encapsulated tumor which was selectively removed without orchiectomy. Within 1 year the signs of precocious puberty disappeared. Ten years later, the patient remained free of disease and had developed normal spontaneous puberty. Despite of highly advanced bone age at the time of diagnosis (13 years according to Greulich and Pyle), his height at age 15 was in the upper normal range and within the familial target height. Most of these prepubertal patients affected by this tumor underwent orchiectomy, although no malignant course of Leydig cell tumors before puberty has been reported. This work provides the first example of long-term follow-up of a prepubertal boy after testis-sparing surgery for a Leydic cell tumor. We conclude that selective removal of the tumor may be the procedure of choice in this entity.

Pseudotumour cerebri after varicella

Thrombotic complications in children with varicella are well known. Transient protein S deficiency due to the presence of an anti-protein S antibody seems to be responsible at least in part. In an 8-year-old girl, pseudotumour cerebri with abducens palsy and ileofemoral vein thrombosis occurred 3 weeks after chickenpox. A transient elevation of anti-protein S auto-antibodies was identified. Under treatment with heparin the pseudotumour cerebri rapidly disappeared but the iliofemoral thrombosis persisted.

CONCLUSION

Thrombotic complications after varicella might be mediated at least in part by antibodies against protein S. Early recognition of this condition permits appropriate treatment with recombinant tissue-type plasminogen activator.

[Insufficient understanding of second tumors after childhood neoplasms in Switzerland]

Second malignancy after childhood neoplasms is a well-known complication. However, frequency differs considerably according to the types of primary neoplasm and the specifics of therapy. Ten patients with a second malignancy after being cured of the primary tumor are described. There were 2 patients with acute lymphoblastic leukemia, one with non-Hodgkin's lymphoma, and one with breast cancer after Hodgkin's disease. Two patients with heritable retinoblastoma developed osteosarcomas in the irradiation field after a latent period of 7 and 14 years respectively. There was another osteosarcoma in a Wilms' tumor survivor. One patient with acute lymphoblastic leukemia developed a secondary AML 10 years after achieving initial remission, and a meningioma was diagnosed in another patient with cured acute lymphoblastic leukemia. One patient died of peritoneal sarcomatosis of unknown origin 20 years after the diagnosis of acute myeloid leukemia. All patients received radiotherapy for the primary neoplasms. Secondary neoplasms in other patients were probably missed because they occurred in adulthood when the patients were transferred to other medical centres. It is impossible to trace these patients because central registration of patients with neoplasms is lacking. It is therefore important to establish a central cancer registry for the whole of Switzerland. Second malignancy after childhood cancer is not a rare event and requires long-term follow-up of patients with neoplasms.

Delayed anti-inflammatory action of nedocromil sodium in the rat paw is dependent on de novo protein synthesis

Nedocromil sodium is commonly suggested to reduce allergic inflammation by inhibiting mediator release from mast cells. However, nedocromil also exhibits a wide range of additional anti-inflammatory activities, including inhibition of increased vascular permeability induced by individual mediators such as histamine. In the present study, we have further characterized the mode of action of nedocromil in a rat model for hind paw edema. Mast cell-dependent edema was induced with compound 48/80 (edema response mainly due to 5-hydroxytryptamine release), and direct mediator-induced plasma extravasation was evoked by exogenous 5-hydroxytryptamine (both agents injected locally). Local pretreatment with nedocromil for 20 min dose-dependently inhibited the edema evoked by compound 48/80 more effectively than that induced by 5-hydroxytryptamine. However, after 2 h pretreatment, both the 5-hydroxytryptamine-and compound 48/80-induced edema responses were inhibited to approximately the same extent by a range of concentrations of nedocromil, as well as by dexamethasone. Local inhibition of RNA/protein synthesis with actinomycin-D abolished the effects of both dexamethasone and nedocromil (2 h local pretreatment). We thus conclude that nedocromil can produce an 'anti-exudative' effect that is independent of inhibition of mast cell mediator release, is slow in onset, and requires de novo protein synthesis.

Impact of prematurity and intrauterine growth retardation on neonatal hemorrhagic and ischemic brain damage

Low birth weight and intrauterine growth retardation are well-recognized risk factors for increased mortality, morbidity and poor neurologic outcome. Risk assessment is different considering true preterm (appropriate-for-gestational-age, AGA) or growth-retarded (small-for-gestational-age, SGA) infants. Therefore, we carried out a study on the incidence of hemorrhagic (peri-intraventricular hemorrhage, PIVH) and ischemic (periventricular leukomalacia) brain lesions in two groups of AGA and SGA very-low-birth-weight (VLBW) infants. In the study period (1987-1990), 111 VLBW babies (< 1,500 g body weight) were serially studied at days 1, 3 and 7 and weekly until discharge by cerebral ultrasonography (ATL, MK 4, 7.5 MHz). 57 were VLBW-AGA babies (mean gestational age 28 weeks, mean body weight 1,106 g). 54 were VLBW-SGA babies (mean gestational age 31 weeks, mean body weight 990 g). PIVH was graded according to the system of Papile et al. Periventricular leukomalacia was defined as an echodensity (> 3 mm) adjacent to the lateral border of the ventricular body. We noted a higher incidence of PIVH in the AGA group (36.8%) than in SGA babies (18.5%; p < 0.01, Fisher test). The AGA subgroup < 1,000 g body weight had 72.2% PIVH compared to AGA babies > 1,000 g (20.5%; p < 0.01). The same relationship was observed in SGA babies (34.8% in < 1,000 g and 6.4% in > 1,000 g babies). Ischemic brain lesions (periventricular leukomalacia) were equally distributed between AGA and SGA babies (10.5 vs. 3.7%, p > 0.5) independently of body weight category.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of do-not-resuscitate orders on length of stay

In 1988, a new do-not-resuscitate policy aimed at assisting professional staff, nurses, patients, and families in end-of-life choices replaced the existing policy at The Cleveland Clinic Foundation. We conducted a retrospective chart review to examine the effects of the new policy on length of stay. Data were collected on demographics, clinical information, length of stay, and the frequency of do-not-resuscitate orders for expired Medicare patients in 1987 (n = 125) and 1989 (n = 135). Length of stay for patients who received a do-not-resuscitate order was significantly reduced in 1989 compared with 1987, partly because the orders were issued earlier in patients' stays in 1989. The number of days from writing the order until death did not change significantly from 1987 to 1989. We conclude that a well-defined do-not-resuscitate policy can reduce length of stay.

[Neurosonographic findings in premature infants and infants with intrauterine growth retardation with a birth weight below 1,500 grams]

The cranial ultrasound of 111 preterm infants were reviewed. 57 patients were appropriate for gestational age (AGA) and 54 small for gestational age (SGA). In the two groups, the incidence of peri-intraventricular hemorrhage (PIVH), posthemorrhagic ventricular dilation (VM) and peri-ventricular leucomalacia (PVL) was compared. PIVH was more common in AGA than in SGA babies (36.8% vs 18.5%). In both groups (AGA and SGA), birth weight less than 1000 g should be considered a further risk factor for hemorrhagic brain lesion (72.2% in AGA babies less than 1000 g and 20.5% ind AGA babies greater than 1000 g birth weight, p less than 0.01) (34.8% in SGA babies less than 1000 g and 6.4% in SGA babies greater than 1000 g birth weight, p less than 0.05). However, ischemic brain lesions (PVL) were not dependent from birth weight (p greater than 0.5). This study shows that low birth weight infants are an eterogeneous group of babies with different risk of hemorrhagic or ischemic cerebral lesion depending on gestational age and birth weight.