What are the respiratory health research priorities in Alberta, Canada? A stakeholder consultation

OBJECTIVE

The Respiratory Health Strategic Clinical Network (RHSCN) was launched to facilitate respiratory and sleep health through implementation of innovative, patient-centred, evidence-informed coordinated services in Alberta. In collaboration with project partners, the RHSCN aimed to determine the respiratory research priorities for Alberta.

DESIGN

The four phases of this research prioritisation project were (1) identifying research questions from stakeholders, (2) determining which research questions had been answered in existing literature, (3) prioritising unanswered questions and (4) finalising the priorities through an inperson workshop.

SETTING

The study occurred in Alberta, Canada over a 2-year period beginning in March 2017.

PARTICIPANTS

A total of 448 patients, clinicians and other stakeholders consented to participate in the survey.

RESULTS

A total of 595 possible questions were submitted, with 343 unique questions identified. Of the questions, 94 were out of scope, 155 answered by existing literature and 10 were combined with others, while 83 were determined to be unanswered in the literature. Stakeholders were surveyed again to prioritise the remaining 83 questions and they were reviewed by the project's Steering Committee (clinicians and patients). At the inperson workshop, the Steering Committee identified 17 research topics as priority areas for respiratory and sleep research in Alberta.

CONCLUSION

A stakeholder-led research prioritisation process identified optimal clinical management/follow-up, equitable access to services, and management of social, psychological and mental health issues related to respiratory/sleep health as priority research areas.

Increased risk of acute stroke among patients with severe COVID-19: a multicenter study and meta-analysis

BACKGROUND AND PURPOSE

Recent observations linked coronavirus disease 2019 (COVID-19) to thromboembolic complications possibly mediated by increased blood coagulability and inflammatory endothelial impairment. We aimed to define the risk of acute stroke in patients with severe and non-severe COVID-19.

METHODS

We performed an observational, multicenter cohort study in four participating hospitals in Saxony, Germany to characterize consecutive patients with laboratory-confirmed COVID-19 who experienced acute stroke during hospitalization. Furthermore, we conducted a systematic review using PubMed/MEDLINE, Embase, Cochrane Library and bibliographies of identified papers following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines including data from observational studies of acute stroke in COVID-19 patients. Data were extracted by two independent reviewers and pooled with multicenter data to calculate risk ratios (RRs) and 95% confidence intervals (95% CIs) for acute stroke related to COVID-19 severity using a random-effects model. Between-study heterogeneity was assessed using Cochran's Q and I2 statistics. International Prospective Register of Systematic Reviews registration number: CRD42020187194.

RESULTS

Of 165 patients hospitalized for COVID-19 (49.1% males, median age = 67 years [57-79 years], 72.1% severe or critical) included in the multicenter study, overall stroke rate was 4.2% (95% CI: 1.9-8.7). Systematic literature search identified two observational studies involving 576 patients that were eligible for meta-analysis. Amongst 741 pooled COVID-19 patients, overall stroke rate was 2.9% (95% CI: 1.9-4.5). Risk of acute stroke was increased for patients with severe compared to non-severe COVID-19 (RR = 4.18, 95% CI: 1.7-10.25; P = 0.002) with no evidence of heterogeneity (I2  = 0%, P = 0.82).

CONCLUSIONS

Synthesized analysis of data from our multicenter study and previously published cohorts indicates that severity of COVID-19 is associated with an increased risk of acute stroke.

Bariatric surgery - a dermatologic perspective

Bariatric surgery has become a standard option in morbid obesity for patients not responding to conventional treatment. A major and stable weight loss can be achieved. Since obesity and weight loss may affect skin diseases, we performed this review to analyse the impact of bariatric surgery on a number of skin diseases. We categorized the skin diseases into three main groups: (i) diseases with a possible benefit from bariatric surgery, (ii) diseases that may develop after bariatric surgery and (iii) diseases that may persist. We hope that dermatologists will achieve an updated knowledge of benefits and possible hazards of this type of surgically induced weight loss.

Metagenomic sequencing of the human gut microbiome before and after bariatric surgery in obese patients with type 2 diabetes: correlation with inflammatory and metabolic parameters

Roux-en-Y gastric bypass (RYGB) has become a prominent therapeutic option for long-term treatment of morbid obesity and type 2 diabetes mellitus (T2D). Cross talk and pathogenetic consequences of RYGB-induced profound effects on metabolism and gut microbiome are poorly understood. The aim of the present study therefore was to characterize intra-individual changes of gut microbial composition before and 3 months after RYGB by metagenomic sequencing in morbidly obese patients (body mass index (BMI)>40 kg m(-)(2)) with T2D. Subsequently, metagenomic data were correlated with clinical indices. Based on gene relative abundance profile, 1061 species, 729 genera, 44 phyla and 5127 KO (KEGG Orthology) were identified. Despite high diversity, bacteria could mostly be assigned to seven bacterial divisions. The overall metagenomic RYGB-induced shift was characterized by a reduction of Firmicutes and Bacteroidetes and an increase of Proteobacteria. Twenty-two microbial species and 11 genera were significantly altered by RYGB. Using principal component analysis, highly correlated species were assembled into two common components. Component 1 consisted of species that were mainly associated with BMI and C-reactive protein. This component was characterized by increased numbers of Proteobacterium Enterobacter cancerogenus and decreased Firmicutes Faecalibacterium prausnitzii and Coprococcus comes. Functional analysis of carbohydrate metabolism by KO revealed significant effects in 13 KOs assigned to phosphotransferase system. Spearmen's Rank correlation indicated an association of 10 species with plasma total- or low-density lipoprotein cholesterol, and 5 species with triglycerides. F. prausnitzii was directly correlated to fasting blood glucose. This is the first clinical demonstration of a profound and specific intra-individual modification of gut microbial composition by full metagenomic sequencing. A clear correlation exists of microbiome composition and gene function with an improvement in metabolic and inflammatory parameters. This will allow to develop new diagnostic and therapeutic strategies based on metagenomic sequencing of the human gut microbiome.

Oral glucose tolerance test and HbA₁c for diagnosis of diabetes in patients undergoing coronary angiography: [corrected] the Silent Diabetes Study

AIMS/HYPOTHESIS

The primary aim of this study was to compare the results of HbA(1c) measurements with those of an OGTT for early diagnosis of 'silent diabetes' in patients with coronary artery disease (CAD) undergoing angiography without prediagnosed diabetes. A secondary aim was to investigate the correlation between the extent of CAD and the glycaemic status of the patient.

METHODS

Data from 1,015 patients admitted for acute (n = 149) or elective (n = 866) coronary angiography were analysed. Patients with known diabetes were excluded from the study. Using the OGTT results, patients were classified as having normal glucose tolerance (NGT), impaired fasting glucose (IFG), impaired glucose tolerance (IGT) or diabetes. According to the results of the HbA(1c) measurements, patients were classified into three groups: normal (HbA(1c) <5.7% [<39 mmol/mol]), borderline (HbA(1c) 5.7-6.4% [39-47 mmol/mol]) and diabetes (HbA(1c) ≥6.5% [≥48 mmol/mol]).

RESULTS

Based on the OGTT, 513 patients (51%) were classified with NGT, 10 (1%) with IFG, 349 (34%) with IGT and 149 (14%) were diagnosed with diabetes. According to HbA(1c) measurements, 588 patients (58%) were classified as normal, 385 (38%) as borderline and 42 (4%) were diagnosed with diabetes. The proportion of patients with IGT and diabetes increased with the extent of CAD (IGT ρ = 0.14, p < 0.001, diabetes ρ = 0.09, p = 0.01). No differences in HbA(1c) were seen among the groups with different extents of CAD (p = 0.652).

CONCLUSIONS/INTERPRETATION

An OGTT should be performed routinely for diagnosis of diabetes in patients with CAD undergoing coronary angiography, since HbA(1c) measurement alone appears to miss a substantial proportion of patients with silent diabetes. A limitation of the study is that the OGTT was not performed before the angiography.

Knowledge of and attitudes towards HIV/AIDS among school teachers in Belize

OBJECTIVES

Although Belize currently has the highest rate of HIV infection in Central America, HIV/AIDS education is not formally included in the school curriculum. We assessed HIV/AIDS-related knowledge and attitudes of Belizean teachers.

METHODS

Ninety-one teachers completed a survey of 55 questions developed by the Centers for Disease Control and Prevention (CDC, Atlanta, Georgia, USA). Four outcomes included 'Knowledge of HIV/AIDS', 'Attitude towards people with HIV/AIDS', 'Instructional confidence', and 'Comfort with sensitive topics'. Multivariable linear regression was used to identify factors associated with the outcomes.

RESULTS

The majority of teachers scored in the average range for all four outcomes, as defined in this study. Statistically significant higher comfort and confidence levels were found for teachers with prior experience teaching responsible sexuality, those with formal training in HIV/AIDS, and for secondary school teachers. Knowledge scores did not differ significantly between any groups.

CONCLUSIONS

While in general teachers in Belize have good HIV/AIDS-related knowledge, attitude, comfort, and instructional confidence, there are several subgroups of teachers who have lower comfort and instructional confidence scores. These subgroups can be targeted for HIV/AIDS training in order to increase their effectiveness as HIV/AIDS educators.

Reduced frequency of peripheral plasmacytoid dendritic cells in type 1 diabetes

Dendritic cells (DCs) as antigen presenting cells play an important role in the initiation of an autoimmune disease like type 1 diabetes. Although there is evidence from the NOD mouse model that the function and frequency of DCs is altered in type 1 diabetes, there is little data on dendritic cells in human type 1 diabetes. We investigated peripheral blood myeloid (mDC1 and mDC2) and plasmacytoid dendritic cells (pDCs) in 15 type 1 diabetes patients with recent onset (within the last 3 months) of type 1 diabetes as well as in 15 patients with long standing (more than 5 years) type 1 diabetes by flow cytometry. Both groups were compared to age matched controls. We observed a significantly reduced percentage of pDCs of peripheral blood mononuclear cells (PBMCs) in both recent onset (0.13 vs. 0.25%, p=0.01) and long standing type 1 diabetes patients (0.13 vs. 0.24%, p=0.01). The absolute counts of pDCs per ml of blood were also significantly lower in both recent onset (mean 9560 vs. 13524, p=0.048) and long-standing diabetes (mean 7869 vs. 12202; p=0.05). The percentage of mDC1 was significantly diminished in recent onset (0.21% vs. 0.30%, p=0.034), but not in long standing type 1 diabetes. Our study demonstrates a persisting reduction of peripheral plasmacytoid DCs in type 1 diabetes patients. Since pDCs are involved in the control of immune responses and inducing regulatory cells, a reduced number of pDCs may predispose to an autoimmune reaction in the pancreatic islets.

Short-term changes in hsCRP and NT-proBNP levels in hypertensive emergencies

Hypertension is associated with high cardiovascular risk. Both hsCRP and NT-proBNP also have been associated with elevated cardiovascular risk, at least in the long term. Much less is known about the short-term changes in these markers, for example, in hypertensive emergencies. In 59 consecutive patients with hypertensive emergencies, hsCRP and NT-proBNP were measured at baseline and at days 3-4 and 7-10 after admission. All patients with hsCRP levels above 10 mg/l during the study were excluded due to possible infections. We found elevated levels of hsCRP at baseline with a significant decline on days 3-4 (day 0: median 2.53 mg/l, days 3-4: median 1.65 mg/l [p<0.01 vs. baseline], days 7-10 median: 2.00 mg/l). Women had higher hsCRP levels than men, and patients with hypertensive cardiomyopathy by echocardiographic criteria had significantly higher hsCRP levels compared with patients without hypertensive cardiomyopathy throughout the study. NT-proBNP levels were clearly elevated at admission (median 158 ng/l) and declined highly significantly thereafter (day 3-4: 61 ng/l, p<0.0001 vs. baseline; day 7-10: 76 ng/l, p<0.0001 vs. baseline). Patients with hypertensive cardiomyopathy had higher NT-proBNP levels compared with those patients without. In hypertensive emergencies, NT-proBNP levels correspond to levels described in acute coronary syndrome and decline significantly under antihypertensive therapy. In addition, we found an acute decline in hsCRP in the short term after hypertensive emergencies. These data may have importance in the clinical setting of hypertensive emergencies and in the interpretation of epidemiological data.

Reduced frequency of peripheral dendritic cells in type 2 diabetes

OBJECTIVE

It is a common clinical experience that type 2 diabetic patients are susceptible to opportunistic infections. The underlying reasons for this immune deficiency are not yet understood. Dendritic cells (DC) play a key role in initiating innate and adapted immune responses.

DESIGN

In order to investigate changes in the DC compartment in the peripheral blood in type 2 diabetes, we analyzed blood from patients under poor and good metabolic control and compared them to healthy controls.

PATIENTS

5 mls of blood were collected from 15 healthy controls, 15 diabetic patients with an HbA1c <7.0 and 15 patients with an HbA1c >9.5%. Age range was 44-80 years. Patients were age-matched with the control group.

MEASUREMENT

Blood DC were enumerated by flow cytometry after staining with antibodies against the blood dendritic cells antigens 1-3 (BDCA 1-3). This allows quantification of the DC subtypes: myeloid dendritic cells type 1 (mDC1, mDC2) and plasmacytoid dendritic cells (pDC).

RESULTS

The relative and absolute frequency for both mDC1 and pDC was clearly diminished in patients with poor metabolic control as compared to healthy controls. In patients with good metabolic control the reduction of DC was less pronounced but still significant, particularly for mDC1.

CONCLUSION

Hyperglycemic metabolism does affect the pool of peripheral DCs and leads to a reduction of both, mDC1 and pDC. Even patients considered to be under good metabolic control appear to have a reduced peripheral pool of DC.

High frequency of unrecognized hypoglycaemias in patients with Type 2 diabetes is discovered by continuous glucose monitoring

AIMS

To evaluate the use of a CGMS in the detection of hypoglycaemia in people with type 2 diabetes as an outpatient procedure.

METHODS

31 type 2 diabetic patients underwent glucose monitoring by means of CGMS (Medtronic MiniMed) for up to three days. Patients took part in at least four SMBG (self monitoring blood glucose) tests per day. After three days of monitoring, the CGMS data was downloaded and analysed by a physician to identify the frequency of hypoglycaemias (< or =50 mg/dl) and borderline values (51-70 mg/dl), their duration and distribution. Findings were discussed with the patient and if necessary treatment was adjusted. Eight weeks later, monitoring was repeated to asses the effects of the adjusted treatment.

RESULTS

Average duration of sensor wear was 4.19 days. Correlation between the sensor and the SMBG readings was high. A high number of hypoglycaemias and borderline values were detected by the CGMS, most of them unrecognized by the patient. The frequency of hypoglycaemias and borderline values just as the duration could be significantly reduced from first to second monitoring.

CONCLUSION

Using the CGMS in type 2 diabetic patients achieved the detection of numerous hypoglycaemias and borderline values both nocturnal and/or unnoticed. The CGMS provides accurate data, which cannot be achieved by conventional SMBG tests. That opens the possibility for treatment adjustment and improvement in metabolic control. For patients it provides a better understanding of the effects of insulin or oral agents, nutrition and exercises to their glucose level.

Implementing sustainable sanitation concepts in Luxembourg: methodological approach and outcomes

The present paper reports the approaches adopted to involve and inform stakeholders at various levels and to identify barriers and needed actions towards the implementation of sustainable sanitation concepts in Luxembourg. The study was split into two phases, starting with a workshop and interviews of important actors/professionals of the water sector such as public administrations, engineering companies and sanitary firms. The second phase consisted of a survey among end-users, developed in order to analyse enabling and disabling factors with respect to sustainable water use in households, and for which over 200 questionnaires were evaluated. Valuable conclusions for the project orientation were derived from these studies in terms of further needs for awareness raising, information and formation. The water professionals pointed to specific questions with respect to the feasibility of sustainable sanitation, such as hygienic concerns or maintenance issues for decentralised technology. A moderate financial commitment towards environmentally friendly techniques as well as a considerable lack of knowledge concerning innovative sanitation concepts was detected for end-users. Based on these findings, tailor-made communication strategies for key stakeholder groups were elaborated and pilot projects were initiated.

Increased prolactin in acute coronary syndromes as putative Co-activator of ADP-stimulated P-selectin expression

Prolactin and leptin are newly recognized platelet co-stimulators due to enhancement of ADP-induced platelet aggregation. The aim of our study was to assess whether both hormones prolactin and leptin play a role as co-activators of platelet activation in patients with acute coronary syndromes. Twenty-one patients with acute coronary syndromes, 10 with stable angina pectoris and 10 controls were studied. Patients with acute coronary syndromes showed significantly higher prolactin and leptin values and a significant increased P-selectin expression on platelets compared to patients with stable angina pectoris or controls. However, patients with acute myocardial infarction as a subgroup of acute coronary syndromes showed the highest prolactin levels as well as ADP stimulated P-selectin expression. In the myocardial infarction subgroup prolactin values showed a significant correlation to ADP stimulated P-selectin expression on platelets (r (2)=0.41; p=0.025), whereas leptin was not correlated. Our data indicate an association between increased prolactin values and enhanced P-selectin expression on platelets in patients with acute coronary syndromes. Therefore, the stress hormone prolactin could be a co-stimulator of platelet activation in these patients. In contrast, the putative platelet activator leptin does not seem to play a major role in acute coronary syndromes.

Effects of growth hormone treatment on B-type natriuretic peptide as a marker of heart failure in adults with growth hormone deficiency

OBJECTIVE

Patients with growth hormone deficiency (GHD) have abnormalities of cardiac structure and function. Growth hormone replacement (GHR) therapy can induce an increase in cardiac mass and improvement in left ventricular ejection fraction. B-type natriuretic peptide (BNP) levels have been successfully used to identify patients with heart failure and they correlate with both disease severity and prognosis.

DESIGN

To investigate the effect of growth hormone replacement on BNP and inflammatory cardiovascular risk factors in adults with GHD we determined NT-proBNP and high sensitive C-reactive protein (CrP) before, 6 and 12 months after GHR.

PATIENTS

Thirty adults (14 males, 16 females) with GHD mean age: 41.7+/-14.5 years (range: 17.2 to 75.4 years) were recruited from the German KIMS cohort (Pfizer's International Metabolic Database).

RESULTS

During 12 months of GHR, a significant increase of IGF-1 (85.4+/-72.1 VS. 172.0+/-98 mug/dl; p=0.0001; IGF-1 SDS mean+/-SD: -3.85+/-3.09 VS. -0.92+/-1.82) was detectable. Mean baseline NT-proBNP was 112+/-130 pg/ml (range: 7 to 562). Twelve patients had normal BNP, whereas 18 revealed NT-proBNP values corresponding to those of patients with heart failure NYHA classification I (n=10), NYHA II (n=6) and NYHA III (n=2), respectively. Baseline BNP levels correlated significantly (p=0.044) with increased baseline CrP values. After 12 months of GHR, a significant decrease (p=0.001) in NT-proBNP levels mean: 68+/-81 pg/ml (range: 5 to 395) was detectable, associated with an improvement in NYHA performance status in 10 of the 18 with increased baseline NT-proBNP.

CONCLUSIONS

Based on our study, approximately two-thirds of patients with GHD have increased NT-proBNP levels which may be useful as screening/diagnostic laboratory parameter for heart failure in such patients. GHR therapy decreases BNP levels in most patients with GHD.

Transient chemokine receptor blockade does not prevent, but may accelerate type 1 diabetes in prediabetic NOD mice

The influx of autoreactive lymphocytes into the site of an autoimmune inflammation is mediated by certain chemokines. Autoimmune insulitis in type 1 diabetes is viewed as the result of destructive Th-1-cells and their corresponding antigen-presenting cells infiltrating the pancreatic islets. Blocking the chemokine receptors that mediate a Th-1-reaction has been shown to reduce autoimmunity in other experimental autoimmune disorders. We used the NOD mouse model to investigate the potency of anti-CCR2 and anti-CCR5 antibodies to inhibit the influx of Th-1-cells into the pancreatic islets, thus preventing diabetes onset. Eleven-week-old female NOD mice were treated with 500 microg of a monoclonal anti-CCR5 or anti-CCR2 or an isotype control antibody every third day over two weeks. We did not observe any preventive effect in either treatment group, but accelerated diabetes onset in the anti-CCR5 treated group. The number of autoantigen-specific Th-1-cells detected in the two treated groups was not reduced, but increased in the anti-CCR5 group. Redundancy within the chemokine system may account for this lack of prevention, or the intervention may have come too late in the disease process. Furthermore, blocking Th-1 chemokine receptors in the late autoimmune process may also inhibit regulatory T-cells, thus accelerating rather than preventing the disease.

Adrenomedullin is a novel marker of tumor progression in neuroendocrine carcinomas

Adrenomedullin is a multi-functional polypeptide hormone. Its involvement in angiogenesis and vasodilator action support the hypothesis that adrenomedullin may be a secretory product of neuroendocrine tumors and contribute to tumor progression. Plasma levels of adrenomedullin were measured by radioimmunoassay in 46 patients with neuroendocrine carcinomas of the gastroenteropancreatic and bronchial system. Tissue expression of adrenomedullin was studied using monoclonal antibodies on pretreated paraffin embedded tissues in a group of 31 patients. Adrenomedullin plasma levels were significantly elevated in patients compared to healthy age-matched controls (p < 0.001). The highest plasma levels were found in patients with neuroendocrine carcinomas of bronchial, midgut and unknown origin. Patients with progressive disease had higher plasma levels than patients with stable disease (p < 0.001). Of the examined tumor samples, 55 % showed cytoplasmic staining for adrenomedullin > 5 % of the total tumor area. Plasma levels and tissue expression of adrenomedullin did not correlate with functional activity of the tumors or presence of the carcinoid syndrome, but did with tumor progression (p < 0.001 and p < 0.014). In conclusion, plasma and tissue expression of the angiogenic peptide adrenomedullin are predictive of tumor progression in patients with neuroendocrine carcinomas. Adrenomedullin might represent a useful prognostic marker in patients with neuroendocrine carcinomas.

Adiponectin in patients with obstructive sleep apnea syndrome: course and physiological relevance

BACKGROUND

Adiponectin is an adipocyte-derived hormone with anti-inflammatory and insulin-sensitizing properties. Insulin resistance is a typical feature of the obstructive sleep apnea syndrome (OSAS).

OBJECTIVES

Since nasal continuous positive airway pressure (nCPAP) treatment improves insulin sensitivity in patients with OSAS, we investigated serum adiponectin levels before and during nCPAP treatment to clarify possible interactions between the adiponectin levels and insulin sensitivity in patients with OSAS.

METHODS

Thirty nondiabetic, obese patients with OSAS (mean age 56.4 +/- 11.1 years; apnoea-hypopnoea index (AHI) 46.03 +/- 19.57) underwent CPAP treatment. Adiponectin levels and the levels of proinflammatory cytokines and proteins reflecting platelet activation [regulated on activation normally T cell expressed and secreted (RANTES) and soluble P-selectin (sCD62p)], as well as the insulin sensitivity index were measured before, and after 2 days and 3 months of CPAP treatment.

RESULTS

Insulin sensitivity increased significantly under nCPAP treatment, whereas adiponectin levels decreased after 2 days of nCPAP treatment, but returned to baseline levels after 3 months of nCPAP treatment. The increase in insulin sensitivity was more pronounced in patients with the highest adiponectin levels at baseline (p = 0.021) after adjustment for body fat (p = 0.003). During treatment, changes in adiponectin levels were highly predictable by the insulin sensitivity index.

CONCLUSIONS

We found a significant relation between adiponectin and the insulin sensitivity index in overweight patients with OSAS. The lack of a long-lasting change in adiponectin may be explained by the overwhelming influence of the body mass index on adiponectin secretion, which was unchanged during nCPAP treatment.

[Management of diabetes mellitus in patients with angiopathies]

Nowadays, about 6-8% of the German population suffers from diabetes mellitus mostly type 2 but in patients with angiopathies about 30% have known diabetes and a further 30% have newly diagnosed diabetes or impaired glucose tolerance. Therefore diagnosis and therapy of glucose impairment play a central role for management of these patients. The antidiabetic therapy for secondary prevention of cardiovascular disease has to be embedded in a multifactorial concept with management of hypertension, hyperlipidemia and hypercoagulability. The management of diabetes following guidelines is a stepwise therapy with lifestyle interventions (diet, exercise) and oral drugs or insulin. Metformin has shown favorable outcome in overweight patients if aware of side effects; insulin is a safe drug in multimorbid patients and with planned interventions or operations. We are awaiting the results of multiple endpoint studies with newer antidiabetic drugs which may change our current concept of management of diabetes mellitus in these patients in the near future.

Differences in platelet activation by prolactin and leptin

Hormones such as prolactin and leptin have recently been recognized as potent platelet aggregation co-activators, and have therefore been postulated as an additional risk factor for both arterial and venous thrombosis. Clinical situations exist that are known to be associated with higher leptin and/or prolactin levels (obesity, pregnancy, prolactinomas and anti-psychotic therapy respectively) and increased venous thrombosis or atherosclerosis risk. Therefore, we compared the impact of both hormones on platelet activation in vitro and in vivo. First, we investigated platelet aggregation and P-selectin expression after stimulation with 1,000 mU/l prolactin or 100 ng/ml leptin in five healthy volunteers in vitro. Prolactin revealed significant higher levels of P-selectin expression and platelet aggregation than leptin in all subjects. We also compared the correlation of prolactin and leptin values with the P-selection expression on platelets. Previously, we detected a significant correlation between prolactin values and ADP-stimulated P-selectin expression on platelets in pregnant women, patients with pituitary tumours, and patients on anti-psychotic therapy. In contrast, leptin did not correlate with P-selectin expression in all subject groups investigated. However, leptin correlated with body mass index in the subjects investigated. Our data indicate that prolactin has a stronger effect on platelet activation as leptin in vitro and in vivo. Moreover, our data suggest that the stronger effect of prolactin on ADP-stimulated platelet aggregation, compared to leptin, depends on higher stimulation of CD62p expression by prolactin.

TSH-Receptor Autoantibodies - Differentiation of Hyperthyroidism between Graves' Disease and Toxic Multinodular Goitre

Previous studies indicate pre-existing subclinical Graves' disease in many patients with the scintigraphic diagnosis of toxic multinodular goitre type A, equivalent to the in Germany so-called disseminated thyroid autonomy. Furthermore, after radioiodine treatment an increase or the induction of TSH-receptor antibodies (TRAb) in patients with Graves' disease or toxic multinodular goitre has been repeatedly reported. The distinction between both hyperthyroid conditions, Graves' disease and toxic multinodular goitre type A, depends on the diagnostic power of the TSH-receptor antibody determination. Bioassays using CHO cell lines expressing the hTSH-receptor or a new TBII assay based on competitive binding to recombinant human TSH-receptor showed a higher sensitivity for the detection of TSH-receptor antibodies in patients with Graves' disease than previous assays using solubilized porcine epithelial cell membranes. In up to 50 % of patients with toxic multinodular goitre A without antithyroid drug pretreatment TSH-receptor antibodies were detectable with a high correlation between thyroid-stimulating antibodies in the bioassay and the h-TBII assay. Moreover, in a recent study the development of TSH-receptor antibodies after radioiodine treatment was detectable in 36 % of patients with toxic multinodular goitre type A, whereas TSH-receptor antibodies were not detectable in patients with toxic multinodular goitre type B or in patients with toxic adenoma. In conclusion, thyroid-stimulating antibodies in a bioassay or TSH-receptor antibodies detected with the h-TBII assay have the highest diagnostic power to differentiate Graves' disease from toxic multinodular goitre. Because of its less cumbersome assay technique the h-TBII should be performed in all patients with hyperthyroidism to differentiate Graves' disease from non-autoimmune hyperthyroidism such as toxic multinodular goitre to select the appropriate therapy for these patients.