Association of glycemic variability and time in range with lipid profile in type 1 diabetes

PURPOSE

Hyperglycemia is associated with abnormalities of lipoproteins. The aim of this study was to analyze, in patients with Type 1 Diabetes (T1D), the association of glycemic control with lipid profile, focusing on glycemic variability and time in range obtained from Continuous Glucose Monitoring (CGM).

METHODS

We performed a retrospective cohort in patients with T1D. We analyzed clinical parameters, HbA1c, CGM and lipid profile in two moments 6 to 18 months apart. We evaluated the association of HbA1c and CGM metrics with lipid profile in cross-sectional (n = 242) and longitudinal (n = 90) analyses.

RESULTS

The mean age of the study population was 36.6 ± 12.6 years, 51.7% were male, and the mean diabetes duration was 16.8 ± 10.3 years. In the cross-sectional analysis, higher HbA1c, higher glucose management indicator (GMI), higher time above range and lower time in range were associated with higher triglyceride levels. In the longitudinal analysis, an increase in time below range was associated with a decrease of HDL cholesterol. In both analyses, an increase in the coefficient of variability (CV) was associated with a significant decrease of HDL cholesterol. HbA1c and CGM were not associated with total cholesterol or LDL cholesterol.

CONCLUSIONS

We observed a negative association between CV and HDL cholesterol levels and a positive association between hyperglycemia metrics and triglyceride levels. These findings suggest that CGM parameters may be a helpful tool to guide the improvement of both glycemic control and lipid profile in T1D.

Time in range and complications of diabetes: a cross-sectional analysis of patients with Type 1 diabetes

BACKGROUND/ OBJECTIVE

To evaluate the association of CGM parameters and HbA1c with diabetes complications in patients with Type 1 Diabetes (T1D).

METHODS

Patients with T1D using the CGM system Freestyle Libre were included in this analysis. The association of CGM-metrics and HbA1c with diabetes complications (any complication, microvascular complications, or macrovascular complications) was assessed using logistic regression unadjusted and adjusted for age, sex, and diabetes duration (model 1), and further adjusted for hypertension and dyslipidemia (model 2).

RESULTS

One hundred and sixty-one patients with T1D were included. The mean (± SD) age was 37.4 ± 13.4 years old and the median T1D duration was 17.7 ± 10.6 years. Time in range (TIR) was associated with any complication and microvascular complications in the unadjusted model and in the adjusted models. TIR was associated with retinopathy in the unadjusted model as well as in model 1, and was associated with macrovascular complications only in the unadjusted model. HbA1c was associated with any complications, microvascular complications, and retinopathy in the unadjusted model but not in the adjusted models. HbA1c was associated with macrovascular complications in the unadjusted model and in the adjusted model 1.

CONCLUSIONS

In this cross-sectional analysis of patients with T1D using intermittent scanned CGM, TIR, and HbA1c were associated with complications of diabetes. TIR may be a better predictor than HbA1c of any complication and microvascular complications, while HbA1c may be a better predictor of macrovascular complications.

The role of Graves' disease in the development of thyroid nodules and thyroid cancer

Aim

The prevalence of thyroid nodules and the risk of thyroid cancer in patients with Graves' disease is uncertain. We aimed to evaluate the prevalence of thyroid nodules and cancer in patients with Graves' disease.

Methods

Retrospective observational study of adult subjects with Graves' disease (positive autoantibodies thyrotropin receptor antibodies (TRAbs)) between 2017 and 2021 at our center was done. We evaluated the prevalence of thyroid nodules and cancer in this population and characterized the predictive factors for thyroid malignancy using linear and logistic regression models.

Results

We evaluated a total of 539 patients with Graves' disease during a median follow-up of 3.3 years (25th-75th percentiles 1.5-5.2 years). Fifty-three percent had thyroid nodules and 18 (3.3%) were diagnosed with thyroid cancer (12 papillary microcarcinomas). All tumors were classified using TNM classification as T1, and only one had lymph node metastasis; there were no recordings of distant metastasis. Sex, age, body mass index, smoking, TSH, and TRAbs levels were not significantly different between patients with and without thyroid cancer. Patients with multiple nodules on ultrasound (OR 1.61, 95%CI 1.04-2.49) and with larger nodules (OR 2.96, 95%CI 1.08-8.14, for 10 mm increase in size) had a greater risk of thyroid cancer diagnosis.

Conclusion

Patients with Graves' disease had a high prevalence of thyroid nodules and their nodules had a significant risk of thyroid cancer. The risk was higher in those with multiple and larger nodules. Most had low-grade papillary thyroid cancer. More studies are needed to clarify the clinical relevance of these findings.

Opioid-free mastectomy under thoracic epidural anesthesia-analgesia in a patient with critical tracheal stenosis: a case report

Mastectomy is traditionally performed under general anaesthesia and invasive ventilation, and is often complemented with regional techniques. In this setting, tracheal stenosis can pose a challenge to airway management. The aim of this report is to describe the successful management of a 68-year-old woman with severe subglottic tracheal stenosis undergoing mastectomy due to breast cancer. Surgery was performed without airway instrumentation under an opioid-free regimen consisting of thoracic epidural, propofol and dexmedetomidine perfusion, and non-opioid analgesics. Spontaneous ventilation and adequate perioperative analgesia were achieved. Opioid-free anaesthesia without airway instrumentation, consisting of thoracic epidural anaesthesia and sedation, is a good alternative in patients undergoing mastectomy in whom airway manipulation is best avoided.

Survey on selenium clinical supplementation in autoimmune thyroid disease

Objective

Previous trials show that selenium could be a very useful tool in the control and treatment of autoimmune thyroid diseases. In this cross-sectional study, through a survey, we aim to evaluate Portuguese endocrinologists' perception and pattern of prescription of selenium supplements in these diseases and verify its agreement with current guidelines.

Methods

The endocrinologists registered in the Portuguese Medical Association were sent an email with a web-based questionnaire, regarding their knowledge and use of selenium supplements in thyroid autoimmune pathology.

Results

A total of 105 physicians (33% of the total) submitted the survey. The selenium serum concentration in the general population was unknown to 80% of respondents. Over a third of respondents have never prescribed selenium for autoimmune thyroid disease. However, 89% are not afraid of recommending it, and 61% indicate Graves' orbitopathy as the pathology they would supplement. In Hashimoto's thyroiditis, 36% of respondents use selenium occasionally or frequently, and this percentage rises to 60% in Graves' disease.

Conclusions

Although recommendations only encompass mild Graves' orbitopathy, selenium is prescribed across the spectrum of autoimmune thyroid diseases, probably due to recent studies that consistently show improvement of biochemical hallmarks in these patients. Further investigation is required on the impact of selenium supplements on primarily clinical outcomes and to identify disorders and/or patients who will benefit the most. Also, there is still insufficient knowledge of this field in the medical community, and evidence-based practice should continue to be promoted by endocrinology societies.

Physical exercise and glycemic management in patients with type 1 diabetes on insulin pump therapy-a cross-sectional study

AIMS

Exercise is an important practice for control in type 1 diabetes (T1D). This study aims to assess de association between exercise and glycemic management in people with T1D and to identify the main barriers to exercise in T1D.

METHODS

We evaluated 95 people with T1D treated with insulin pump therapy. Participants answered a questionnaire about 1) exercise habits, 2) usual adjustments in insulin and food intake with exercise and 3) main barriers to exercise. Continuous glucose monitoring (CGM) was used to evaluate time in range (TIR), time below range (TBR) and time above range (TAR) during the last 60 days before the evaluation. CGM data during, before (2 h before) and after (24 h after) the last bout of exercise was also evaluated.

RESULTS

The mean age was 30.1 ± 12.1 years, and 51.6% were women. Participants that reported practicing exercise (55.8%) had a higher TIR (59.6 ± 16.3 vs. 48.7 ± 15.7, p = 0.012) and a lower TAR (32.6 ± 15.8 vs. 45.4 ± 17.7, p = 0.006). Comparing with the 60 days CGM data, the TBR was lower in the 2 h before exercise (- 1.8 ± 3.8, p = 0.0454) and TAR was lower during (- 16.9 ± 33.6, p = 0.0320) and in the 24 h after (- 8.7 ± 17.2, p = 0.032) the last bout of exercise. The absence of adjustments on insulin and food intake was associated with higher TBR after the exercise (13.44 ± 3.5, p < 0.05). Eating before the exercise and turning off the pump during the exercise were associated with lower TBR after exercise (food booster: - 7.56 ± 3.49, p < 0.05; turning off insulin pump - 8.87 ± 3.52, p < 0.05). The main barriers reported for exercise practicing were fear of hypoglycemia, lack of free time and work schedule.

CONCLUSION

Exercise was associated with better glycemic management in people with T1D. Addressing common barriers may allow a higher adherence to exercise in T1D.

ODP204 Hemochromatosis and endocrine dysfunctions – a case report

Introduction

Hemochromatosis is characterized by iron overload that can lead to deposit in various organs such as liver, pancreas, pituitary gland, resulting in endocrine dysfunction. Pancreatic iron deposition can lead to diabetes mellitus, and pituitary deposition to hypopituitarism. Liver is the principal affected organ and that can lead to various complications like hepatomegaly, cirrhosis, and hepatocellular carcinoma.

Case report

A 67 years-old caucasian man was diagnosed with hemochromatosis at 30 years old. At that time, undergoing periodic phlebotomies. After 3 years, he was diagnosed with diabetes mellitus and started basal-bolus insulin therapy. In 2006 he submitted to laser photocoagulation due developed to non-proliferative retinopathy. At the present presents microalbuminuria with urine albumin to creatinine ratio of 65. 0 mg/g. The pituitary function reveals hypogonadotropic hypogonadism with no other axis affected. He was medicated with 250 mg enanthate testosterone injection monthly. He also developed cirrhosis Child-Pugh A and in 2018 was diagnosed with multicentric hepatocarcinoma. He was submitted at radioembolization of hepatic lesions in 2019 and in 2021. Due to disease progression, he started treatment with tyrosine kinase inhibitors (sorafenib 800 mg daily) in 2021. Recently, atrial fibrillation was diagnosed, and he started anticoagulation with apixaban 5. 0 mg twice a day.

Conclusion

Secondary causes of endocrinopathies such as diabetes mellitus and hypogonadism are relatively infrequent. This case alerts to diseases associated with hemochromatosis at long term, such as diabetes mellitus, hypogonadism, cirrhosis and hepatocarcinoma.

Presentation: No date and time listed

Detection of SARS-CoV-2 infection in thyroid follicular cells from a COVID-19 autopsy series

OBJECTIVE

To understand whether thyroid cells can be directly infected by the SARS-CoV-2 virus and to establish a putative correlation with the expression of the host entry machinery: ACE-2, TMPRSS2, and furin.

METHODS

We assessed the presence of SARS-CoV-2 virus at the gene level by RT-PCR, viral RNA transcripts localization by in situ hybridization, and by detecting viral proteins by immunohistochemistry for the nucleocapsid and the spike proteins. Furthermore, we also described the immunoexpression of key host factors for virus entry in the COVID-19 thyroid samples.

RESULTS

We performed RT-PCR for SARS-CoV-2 in all autopsy specimens and detected viral genome positivity in 13 of 15 thyroid tissues and in a lung specimen. In 9 of the 14 positive samples, we were also able to confirm SARS-CoV-2 signal by in situ hybridization. Immunohistochemistry for the viral nucleocapsid and spike protein was also positive for ten and nine of the RT-PCR-positive cases, respectively, but revealed a lower sensitivity. We also described, for the first time in a COVID-19 series, the immunohistochemical expression of ACE-2, TMPRSS2, and furin in the thyroid.

CONCLUSIONS

Our results obtained in thyroid specimens from deceased COVID-19 patients indicate that thyrocytes can be directly infected by SARS-CoV-2 since we detected the presence of SARS-CoV-2 genome in follicular cells. Nevertheless, we did not find a clear correlation between the presence of viral genome and the expression of the host factors for virus entry, namely ACE-2, TMPRSS2, and furin.

Predictors of the effectiveness of insulin pumps in patients with type 1 diabetes mellitus

PURPOSE

Insulin pump therapy has become the preferential treatment for type 1 diabetes (T1D) as it mimics the physiological secretion of insulin better than multiple daily injections. However, not all patients improve with insulin pump therapy. This study aims to determine the predictors of the effectiveness of insulin pumps in T1D.

METHODS

We conducted a retrospective observational study of patients who started insulin pumps. Data from four timepoints (before, at 6, 12, and 36 months) were evaluated for outcomes of glycemic control and safety. The association of baseline predictors with outcomes was analyzed using linear and logistic regression models.

RESULTS

We evaluated 136 patients (57.4% females, age 36 ± 12 years, duration of T1D 14 ± 9 years). During the follow-up, there was a mean decrease of HbA1c of 0.9 ± 1.2%. The improvement in HbA1c was independent of sex, age, and duration of T1D. Higher baseline HbA1c, family history of diabetes, and not being treated with statins were predictors of improvement in HbA1c. Not being treated with statins and higher baseline HbA1c predicted improvement in HbA1c without worsening hypoglycemia. History of hypoglycemia was a predictor of severe hypoglycemia. Family history, higher baseline HbA1c, and psychological/psychiatric disorders were predictors of ketoacidosis.

CONCLUSION

Benefits of insulin pump were independent of sex, age, and duration of T1D. Baseline HbA1c, family history of diabetes, treatment with statins, history of hypoglycemia, and psychological/psychiatric disorders were predictors of outcomes, and may allow the identification of patients who benefit most from insulin pump therapy or who are at increased risk of complications.

Quality of Life in Patients With Hypothyroidism

Introduction: The quality of life (QoL) of thyroid diseases has been less studied than other chronic diseases. There is however evidence suggesting long lasting physical and psychological symptomatology related to thyroid diseases.

Objective: To analyze the QoL in patients with hypothyroidism.

Methods: We evaluated 274 patients with a mean age of 56.2 ± 14.2 years, 89.1 % female and divided them by diagnosis: autoimmune thyroiditis (AIT, n = 145), multinodular goiter (MG, n = 31), total thyroidectomy (TT) for thyroid cancer (n = 46), total thyroidectomy for MG (n = 36), TT for Graves disease (GD, n = 9) and radioactive iodine therapy (RAI) for GD (n = 7), and assessed thyroid function tests, thyroid antibodies, lipid profile, high-sensitivity C-reactive protein, vitamin B12, folic acid and applied the Thyroid Dependent Quality of Life questionnaire (ThyDQoL). Statistical analysis was performed with the One-way ANOVA test and Pearson’s correlation test. P values ≤ 0.05 were considered as statistically significant.

Results: In this sample, the subgroups who reported worse QoL were the TT for thyroid cancer (-2.47 points) followed by the RAI for GD (-2.14 points) and the AIT (-2.11 points), although these differences were not statistically significant. Regarding the internal domains of the ThyDQoL, we found a significant difference between the subgroup TT for thyroid cancer and MG in bodily discomfort (-4.03 ± 3.61 vs -1.47 ± 1.66; p = 0.04) and household tasks (-2.95 ± 2.92 vs -0.90 vs 1.61; p = 0.02). Within the subgroups, we observed significant correlations involving QoL and vitamin B12 in the AIT subgroup (r = 0.16; p = 0.05), between QoL and lipoprotein(a) (r = -0.50; p = 0.03) in the MG subgroup, between QoL and free T3 (r = -0.31; p = 0.03) in the TT for thyroid cancer subgroup and between QoL and free T3 (r = -0.76; p = 0.04) in the RAI for GD subgroup.

Conclusions: In this study we found that patients submitted to TT for thyroid cancer had the worse QoL among patients with hypothyroidism. This may be related to the use of thyroid hormone suppressive therapy. We also observed that certain domains of QoL are more affected by some causes of hypothyroidism. Further studies are needed to analyze more deeply the symptomatology that contributes to worsening of QoL in these patients.

Influence of prenatal exposure to dexamethasone on neurodevelopmental behaviour

Introduction Early life stress, such as prenatal exposure to exogenous glucocorticoids (GC), can have a negative impact on brain development. Dexamethasone (DEX) is a synthetic GC used in preterm pregnancies to promote lung maturation. However, prenatal exposure to DEX induces an anxious-like behaviour in male and female offspring at adulthood. Notably, only males respond positively to therapeutics with a proposed anxiolytic.

Objectives Since the influence of prenatal DEX on neurodevelopmental behaviour remains to be elucidated and could help explain this difference in drug efficacy, we aim to clarify the effects of this GC on neurodevelopment during infancy, comparing male and female offspring neurodevelopment at this early age.

Methodology To obtain an animal model of chronic anxiety, Wistar pregnant dams were injected subcutaneously with DEX (1mg/kg) on gestational days 18 and 19. The vestibular system development, locomotion, upper limbs strength, discriminatory ability, auditory response and eye opening day were assessed in male and female offspring between P5 and P17. Animal procedures were approved by the Animal Welfare Committee and done in agreement with the law.

Results Male and female offspring prenatally exposed to DEX had a better performance in the tests assessing the vestibular system development and discriminatory ability, especially at P5 and P6. Additionally, DEX anticipated the day of eye opening and had a positive impact in the upper limb strength of the offspring of both sexes. However, the locomotor ability and auditory response were impaired comparing with controls.

Conclusion Exposure to DEX improves limb strength, balance, spatial orientation and anticipates eye opening. These results may suggest that prenatal DEX exposure promotes offspring development and maturation in both males and females. Prenatal DEX did not differently affect male and female neurodevelopment at early age. It remains to clarify the underlying motives that induce a dimorphic gender response to anxiolytic therapy in adulthood.

SAT-431 Insulin Resistance, Lipid Profile and High-Sensitivity C-Reactive Protein in Patients with Autoimmune Thyroiditis

Introduction: Thyroid function and autoimmunity has been associated with cardiovascular events in patients with autoimmune thyroiditis. Objectives: To evaluate the association between thyroid function, antithyroid antibodies levels, insulin resistance and markers of cardiovascular risk in patients with autoimmune thyroiditis. Methods: We evaluated 228 patients with autoimmune thyroiditis, 93.9 % female, with a mean age of 47.06 ± 15.35 years. We analyzed thyroid function, anti-thyroglobulin antibodies (anti-Tg), anti-thyroid peroxidase antibodies (anti-TPO), HOMA-IR, HOMA-B, QUICKI, HISI (Hepatic Insulin Sensitivity Index), WBISI (Whole-Body Insulin Sensitivity Index), the levels of lipid profile, high-sensitivity C-reactive protein (hs-CRP), homocysteine, folic acid, and vitamin B12. We defined 3 groups based on TSH levels: TSH between 0.35-2.49 µUI/ml, (n = 166), TSH between 2.50-4.94 µUI/ml, (n = 43) and TSH over 4.95 µUI/ml, (n = 19), and normal levels of free T4 and free T3. A 75-g OGTT was performed in the morning and blood samples were obtained every 30 min for 120 min for measurements of plasma glucose, insulin, and C-peptide. For the statistical analysis we used the Mann-Whitney test and Spearman correlations. Results are expressed as means ± SD or percentages. A two-tailed p<0.05 was considered statistically significant. Results: There were no significant differences regarding median age or median BMI between groups. We did not find any significant differences comparing group with TSH 0.35-2.49 and group with TSH 2.50-4.94, in all parameters evaluated. Group with TSH 2.50-4.94 had higher indexes of QUICKI (0.69 ± 0.39 vs 0.48 ± 0.13; p = 0.02) and HISI (79.83 ± 63.72 vs 41.73 ± 29.02; p = 0.01) than group with TSH over 4.95. The group with TSH over 4.95 demonstrated a higher index of HOMA-IR than group with TSH 2.50-4.94 (3.77 ± 2.93 vs 1.95 ± 1.24; p = 0.01). In the TSH 0.35-2.49 group we found significant correlations between TSH and HOMA-IR (r= 0.18; p = 0.01), total cholesterol and anti-TPO (r =0.23; p = 0.002), anti-Tg and HDL-cholesterol (r= -0.17; p=0.002), anti-Tg and triglycerides (r=0.34; p < 0.001), and anti-Tg and LDL-cholesterol (r=0.16; p=0.03). In the TSH 2.50-4.94 group we observed positive correlation between Apo A1 and HOMA-B (r=0.58; p<0.001), HOMA-IR and LDL-cholesterol (r=0.34; p=0.02) and WBISI and HDL-cholesterol (r=0.34; p=0.02). In the TSH over 4.95 group we observed a correlation between TSH and triglycerides (r=0.70; p<0.001) and between anti-Tg and hs-CRP (r=0.64; p=0.004). Conclusions: The association among TSH, lipid profile, insulin resistance, hs-CRP and antithyroid antibodies in patients with autoimmune thyroiditis may contribute to an increased cardiovascular risk, not only in patients with subclinical hypothyroidism but also in those classified as euthyroid.

P852 Cancer-associated thrombotic diathesis: one of your worst nightmares

A 34-year-old male patient was diagnosed with undifferentiated sarcoma of the right thigh, with lung metastasis. He underwent primary lesion resection surgery and initiated chemotherapy with both doxorubicin and ifosfamide. Though primary tumor burden was substantially reduced, secondary lesions were found to be irresponsive to drug therapy, leading to regimen switching to both gemcitabine and docetaxel. Three months later, patient started complaining of atypical chest pain and palpitations. Electrocardiography revealed very frequent supraventricular ectopic complexes, while a transthoracic echocardiogram unveiled a pulmonary vein thrombus, which extended into the left atrium. This finding, which was further characterized by cardiovascular magnetic resonance imaging, prompted anticoagulation initiation, under the form of enoxaparin 1mg/kg bid. At this time, chemotherapeutic scheme was, again, swapped, and a cycle of both doxorubicin and olaratumab was introduced. A combined episode of inferolateral ST-segment elevation myocardial infarction and peripheral arterial embolism followed shortly thereafter. Emergent invasive coronary angiogram revealed no signs of both epicardial atherosclerosis and thrombus, whereas subsequent transthoracic echocardiography showed a massive left heart thrombus, extending into the aortic valve annulus. Anti-thrombotic approach involved increasing enoxaparin dosage to 1.5mg/kg bid but no fibrinolytic therapy. Despite a rather uneventful immediate clinical course, with no electric or hemodynamic instability and no limb-threatening ischemia, lamentably, patient died two weeks later, before thrombus definitive imaging reassessment. As no autopsy was performed, it is unclear whether a cardiovascular acute event or neoplasm inexorable progression is to blame as the primary cause of death.

Thrombosis is a common, costly and potentially fatal cancer complication. Patients receiving systemic chemotherapy for advanced diseased are at higher risk. Despite major management developments in the past fifteen years, evidence still supports traditional low-molecular-weight heparins as the first-line therapy and prognosis remains dismal.

Abstract P852 Figure.

Interaction of Genetic Variations in NFE2L2 and SELENOS Modulates the Risk of Hashimoto's Thyroiditis

Background: Several single-nucleotide polymorphisms (SNPs) are known to increase the risk of Hashimoto's thyroiditis (HT); such SNPs reside in thyroid-specific genes or in genes related to autoimmunity, inflammation, and/or cellular defense to stress. The transcription factor Nrf2, encoded by NFE2L2, is a master regulator of the cellular antioxidant response. This study aimed to evaluate the impact of genetic variation in NFE2L2 on the risk of developing HT. Methods: In a case-control candidate gene association study, functional SNPs in the NFE2L2 promoter (rs35652124, rs6706649, and rs6721961) were examined either as independent risk factors or in combination with a previously characterized HT risk allele (rs28665122) in the gene SELENOS, encoding selenoprotein S (SelS). A total of 997 individuals from the north of Portugal (Porto) were enrolled, comprising 481 HT patients and 516 unrelated healthy controls. SELENOS and NFE2L2 SNPs were genotyped using TaqMan^® assays and Sanger sequencing, respectively. Odds ratios (ORs) were calculated using logistic regression, with adjustment for sex and age. Expression of SelS was analyzed by immunohistochemistry in thyroid tissue from HT patients and control subjects. Molecular interactions between the Nrf2 and SelS pathways were investigated in thyroid tissues from mice and in rat PCCL3 thyroid follicular cells. Results: When all three NFE2L2 SNPs were considered together, the presence of one or more minor alleles was associated with a near-significant increased risk (OR = 1.43, p = 0.072). Among subjects harboring only major NFE2L2 alleles, there was no increased HT risk associated with heterozygosity or homozygosity for the SELENOS minor allele. Conversely, in subjects heterozygous or homozygous for the SELENOS risk allele, the presence of an NFE2L2 minor allele significantly increased HT risk by 2.8-fold (p = 0.003). Immunohistochemistry showed reduced expression of SelS in thyroid follicular cells of HT patients. In Nrf2 knockout mice, there was reduced expression of SelS in thyroid follicular cells; conversely, in PCCL3 cells, reducing SelS expression caused reduced activity of Nrf2 signaling. Conclusions: The NFE2L2 promoter genotype interacts with the SELENOS promoter genotype to modulate the risk of HT in a Portuguese population. This interaction may be due to a bidirectional positive feedback between the Nrf2 and SelS pathways.

MON-620 Autoimmune Thyroiditis, Benign Nodular Thyroid Disease and Adipokines Levels

Introduction: The interrelationship between autoimmune thyroiditis, benign nodular thyroid disease and plasma adipokines levels remains elusive. We aimed to compare the levels of adipokines in patients with autoimmune thyroiditis with and without benign nodular thyroid disease. Subjects and Methods: We recorded thyroid function tests, BMI, the levels of total cholesterol(TC), HDL, LDL-cholesterol, triglycerides(TG), apolipoprotein B(ApoB), ApoA1, lipoprotein(a)(Lp[a]), homocysteine, CRP(C-reactive protein), folic acid, vitamin B12 levels,adiponectin, resistin and plasminogen activator inhibitor-1 (PAI-1) in 98 patients with autoimmune thyroid disease, 75.9% woman, with a mean age of 46.7±15.3 years. An ultrasound scan of the thyroid gland was performed in all patients. Patients were divided according to thyroid function (euthyroidism, hypothyroidism or hyperthyroidism) and presence of benign nodular thyroid disease (unimodular goitre [UNG], multinodular goitre [MNG]). Results: Patients with hyperthyroidism showed higher levels of resistin comparing with those with hypothyroidism (28.3±14.7 vs 20.7±22.6 ng/ml, p<0.01), PAI-1 (27.3±25.1 vs 12.7±10.9 ng/ml, <0.01) and lower levels of adiponectin (21.0±13.3 vs 28.3±14.7 μg/ml, p<0.01). In both hypothyroidism and hyperthyroidism, adiponectin, resistin and PAI-1 were not correlated with BMI. Among patients with hypothyroidism, the group with MNG presented lower adiponectin levels than the group without nodules (12.9±6.3 vs 23.7±14.4 μg/ml, p<0.01). The group with UNG had significantly higher resistin levels than patients with MNG (34.2±40.18 vs 7.2±2.5 ng/ml, p<0.01). On the other hand, among patients with normal thyroid function, those with MNG presented significantly higher levels of resistin comparing with those with UNG (16.2±15.3 vs 8.0±7.8 ng/ml, p<0.05). Regarding the group with hyperthyroidism, patients with MNG had significantly higher levels of PAI-1 comparing with the group with UNG (30.2±27.4 vs 18.8±15.8 ng/ml, p<0.05). Conclusions: We found significant associations between benign nodular thyroid disease and adipokines levels among patients with AIT. This relationship seems to be modulated by thyroid function. Our results suggest that adipokines may have an important role in the pathogenesis of benign nodular thyroid disease among patients with AIT.

Selenium and Selenoproteins in Immune Mediated Thyroid Disorders

Selenium is an essential micronutrient that is required for the synthesis of selenocysteine-containing selenoproteins, processing a wide range of health effects. It is known that the thyroid is one of the tissues that contain more selenium. The “selenostasis” maintenance seems to contribute to the prevention of immune mediated thyroid disorders. Prospective, observational studies, randomized, controlled studies evaluating selenium supplementation, and review articles that are available in Medline and PubMed have undergone scrutiny. The differences concerning methodology and results variability have been analyzed. Several authors support the idea of a potential efficacy of selenium (mainly selenomethionine) supplementation in reducing antithyroperoxidase antibody levels and improve thyroid ultrasound features. In mild Graves’ orbitopathy, selenium supplementation has been associated with a decrease of the activity, as well as with quality of life improvement. Future research is necessary to clearly understand the selenium supplementation biologic effects while considering the basal selenium levels/biomarkers, selenoprotein gene polymorphisms that may be involved, underlying comorbidities and the major clinical outcomes.

Severe hypoglycaemia in diabetic patients in Pre-hospital and Emergency Department care: a cross-sectional survey

OBJECTIVE

We aimed to characterize hypoglycaemia episodes and patients examined by a Pre-hospital Medical Emergency Unit (PH) and in the Emergency Department (ED) of our hospital.

RESULTS

We identified 86 episodes of severe hypoglycaemia (PH: n 37; ED: n 49; both: n 12). Hypoglycaemia accounted for 4.7% of all emergency calls attended by the PH (n 793) and 0.11% of all ED episodes (n 54,366). Among episodes examined by the PH, 64.5% of involved patients had type 2 diabetes and 54.1% were not referred to the ED. Transportation of the patient to the ED was more likely in type 2 diabetes (p = 0.014). Among episodes evaluated in the ED 66.1% of the patients were more than 65 years old and 81.4% had type 2 diabetes. 66% of the patients were insulin treated. One-third of examined patients were admitted to the ward, the majority having type 2 diabetes.

Clinical Correlations in Hiv-1 and Hiv-2 Infected Patients

In Portugal, the prevalence of human immunodeficiency virus type 2 (HIV-2) seropositivity is higher than in other European countries or North America. Recent literature data points out a possible difference on the pathogenic potential and on the natural history of HIV-1 and HIV-2, suggesting a lower virulence of HIV-2. Facing these hypothesis and the increasing number of HIV-2 cases, we analysed two infected groups HIV-1 and HIV-2, trying to correlate the ophthalmologic lesions present in both populations and searching for a difference in the clinical presentation of the ocular disorder. We studied prospectively 214 patients with HIV infection at several stages, 83% HIV-1 and 17% HIV-2. Ocular manifestations were present in both populations with a significant prevalence in HIV-1 (48%), compared to HIV-2 (19%) (p<0.005). The ophthalmologic pathology found, particularly noninfectious retinopathy, infectious retinitis and neuro-ophthalmic disorders, were considered important for the disease's diagnosis and prognosis. All these ophthalmic findings were present in the HIV-1 population. In the HIV-2 group the most frequent lesion was noninfectious retinopathy. Within each group, HIV-1 and HIV-2, the comparison of the survival between AIDS patients with and without ocular lesions, revealed a significant shorter survival time in those with ocular pathology (p<0.001 and p<0.05). There seems to exist a certain analogy in clinical expression in both groups, although it is possible to admit a lower severity in ocular involvement in patients infected by HIV-2.

Pituitary incidentalomas: analysis of a neuroradiological cohort

PURPOSE

Most pituitary lesions are detected during the investigation of symptoms associated with hormonal dysfunction and vision abnormalities. When the lesion is identified in an image performed for reasons not related to the tumor, the term incidentaloma applies. Our aim was to describe the diagnosis behind pituitary incidentalomas, patient characteristics and their follow up.

METHODS

We searched for the terms "pituitary", "hypophysis" and "incidentaloma" in the requisitions and reports of all CTs and MRIs performed between 1st September 2008 and 30th October 2013. We retrieved demographic data as well as information regarding presentation and follow-up.

RESULTS

We detected 71 pituitary incidentalomas, 3 in children/adolescents. In adult patients, mean age was 51.6 ± 18.46 years and 42 were female (61.8 %). The most frequent reason for imaging was headache (33.8 %). The image that first detected the incidentaloma was CT scan in 63.2 and 17.6 % patients presented symptoms that could have led to earlier diagnosis. Pituitary adenoma is the most prevalent lesion (n 48; 70.6 %), followed by Rathke's cleft cyst (n 9; 13.2 %). Hormonal evaluation revealed hypopituitarism in 14 patients and hypersecretion in 6: 5 prolactinomas and 1 somatotroph adenoma. Twenty-one (28.8 %) patients underwent surgery and there was no malignancy.

CONCLUSIONS

In concordance with available literature, adenomas are the most frequent incidentally found pituitary lesions. Hormonal dysfunction is quite prevalent, including symptomatic presentations, which suggests that there seems to be a low sensitivity for the diagnosis of pituitary disease.

Polymorphisms in the TNFA and IL6 genes represent risk factors for autoimmune thyroid disease

BACKGROUND

Autoimmune thyroid disease (AITD) comprises diseases including Hashimoto's thyroiditis and Graves' disease, both characterized by reactivity to autoantigens causing, respectively, inflammatory destruction and autoimmune stimulation of the thyroid-stimulating hormone receptor. AITD is the most common thyroid disease and the leading form of autoimmune disease in women. Cytokines are key regulators of the immune and inflammatory responses; therefore, genetic variants at cytokine-encoding genes are potential risk factors for AITD.

METHODS

Polymorphisms in the IL6-174 G/C (rs1800795), TNFA-308 G/A (rs1800629), IL1B-511 C/T (rs16944), and IFNGR1-56 T/C (rs2234711) genes were assessed in a case-control study comprising 420 Hashimoto's thyroiditis patients, 111 Graves' disease patients and 735 unrelated controls from Portugal. Genetic variants were discriminated by real-time PCR using TaqMan SNP genotyping assays.

RESULTS

A significant association was found between the allele A in TNFA-308 G/A and Hashimoto's thyroiditis, both in the dominant (OR = 1.82, CI = 1.37-2.43, p-value = 4.4×10(-5)) and log-additive (OR = 1.64, CI = 1.28-2.10, p-value = 8.2×10(-5)) models. The allele C in IL6-174 G/C is also associated with Hashimoto's thyroiditis, however, only retained significance after multiple testing correction in the log-additive model (OR = 1.28, CI = 1.06-1.54, p-value = 8.9×10(-3)). The group with Graves' disease also registered a higher frequency of the allele A in TNFA-308 G/A compared with controls both in the dominant (OR = 1.85, CI = 1.19-2.87, p-value = 7.0×10(-3)) and log-additive (OR = 1.69, CI = 1.17-2.44, p-value = 6.6×10(-3)) models. The risk for Hashimoto's thyroiditis and Graves' disease increases with the number of risk alleles (OR for two risk alleles is, respectively, 2.27 and 2.59).

CONCLUSIONS

This study reports significant associations of genetic variants in TNFA and IL6 with the risk for AITD, highlighting the relevance of polymorphisms in inflammation-related genes in the etiopathogenesis of AITD.

A polymorphism in the promoter region of the selenoprotein S gene (SEPS1) contributes to Hashimoto's thyroiditis susceptibility

CONTEXT

The association between selenium and inflammation and the relevance of selenoproteins in follicular thyroid cell physiology have pointed to a putative role of selenoproteins in the pathogenesis of autoimmune thyroid diseases.

OBJECTIVE

The aim of this study was to evaluate the role of a promoter variation in SEPS1, the selenoprotein S gene, in the risk for developing Hashimoto's thyroiditis (HT).

DESIGN

A case-control study was performed to assess the association of genetic variation in the SEPS1 gene (SEPS1 -105G/A single-nucleotide polymorphism, rs28665122) and HT.

SETTING

The study was conducted in north Portugal, Porto, in the period of 2007-2013.

PATIENTS OR OTHER PARTICIPANTS

A total of 997 individuals comprising 481 HT patients and 516 unrelated controls were enrolled in the study.

MAIN OUTCOME MEASURES

Genetic variants were discriminated by real-time PCR using TaqMan single-nucleotide polymorphism genotyping assays.

RESULTS

There is a significant association between the SEPS1 -105 GA and AA genotypes and HT [odds ratio (OR) 2.24, confidence interval (CI) 1.67-3.02, P < 5.0 × 10(-7), and OR 2.08, CI 1.09-3.97, P = .0268, respectively]. The A allele carriers are in higher proportion in the patient group than in the control population (46.2% vs 28.1%, P < 5.0 × 10(-7)) with an OR (CI) of 2.22 (1.67-2.97). The proportion of patients carrying the A allele is significantly higher in male patients with HT, representing a 3.94 times increased risk (P = 7.9 × 10(-3)).

CONCLUSION

Our findings support the existence of a link between SEPS1 promoter genetic variation and HT risk.

[Hypoglycemia in the diabetic patient: the controversy in its study, in search of its implications]

Hypoglycemia is one of the greatest limitations regarding the treatment of diabetes, as well as one of the most expensive. Its relevance goes beyond the episode itself or the rare sequel. The occurrence of hypoglycemia is frequently followed by treatment adjustments involving the glycemic target, which can result in long term diabetes complications. Its medium and long term consequences are not yet understood in light of recent studies, which have renewed fears regarding an increased cardiovascular risk with its occurrence. Controversy around its definition, as well as serious methodological limitations, led to disparities between the results of the multiple studies of incidence and costs. The low adhesion of a significant number of diabetic patients to glycemic self-monitoring during symptomatic episodes leads to diagnostic uncertainty and, occasionally, to a worsening of the glycemic control. The health-care based studies result in great underestimation of its incidence given the fact that many episodes are mild in nature, and some severe hypoglycemic episodes are treated by the patient's family or friends. Recent studies revealed that a significant number of severe hypoglycemic episodes treated by health-care professionals doesn't involve transportation to an Emergency Department. The same data suggest that the largest portion of the direct and indirect costs of diabetic hypoglycemia is related to the episodes that are treated at the Hospital, particularly if the patient is admitted in the ward. In the past decades a great investment has been made in the development of multiple strategies for the avoidance of hypoglycemia, namely the continuous blood glucose monitoring devices, as well as new drugs. In spite of the efforts, hypoglycemia remains as one of the most important problems in the treatment of diabetes.

Abordagem da orbitopatia associada à tiróide

Thyroid associated orbitopathy is a clinical entity with pathogenic mechanisms not fully understood, and appears in about 90% of cases in association with hyperthyroidism of Graves' disease. Its approach involves the recognition of typical features and the exclusion of other diseases in the less common presentations. The treatment is conditioned by the determination of the activity and severity of the disease. The restoration of the euthyroid state and avoiding of hypothyroidism are essential in mitigating the progression of orbitopathy. Glucocorticoid intravenous therapy is the treatment of choice in the active phase and surgical treatment in the inactive phase. Radiotherapy and cyclosporine in combination with corticosteroids are alternatives when monotherapy is insufficient in the active phase. Treatment should be instituted in specialized centers, with ophthalmologists and endocrinologists acting in synergy to avoid consequences of delays in intervention and in optimizing therapy.

[Continuous subcutaneous insulin infusion]

BACKGROUND

Continuous subcutaneous insulin infusion (CSII) and multiple daily injections (MDI) represent two strategies of intensive insulin therapy, obtaining a strict metabolic control. The importance of such rigorous metabolic control in reducing the frequency and severity of diabetes long-term complications was highlighted by the Diabetes Control and Complication Trial (DCCT).

AIM

To review the experience in the use of ISCI at Hospital São João, comparing it with the therapeutic modality of MID, regarding metabolic control, weight and body mass index (BMI), microalbuminuria, frequency of adverse events, lipid profile and quality of life.

METHODS

This retrospective, observational study included 25 type 1 diabetic patients followed-up on Endocrinology outpatient at Hospital São João, receiving CSII for more than 3 months after they were treated with MDI also for a period exceeding 3 months. For both periods of treatment, clinical data were obtained on the quality of glycaemic control (assessed by the levels of glycated hemoglobin--A1c), lipid profile, weight and body mass index (BMI) and microalbuminuria. To evaluate the impact on quality of life we used the ADDQoL questionnaire. A questionnaire was also used to determine the frequency of adverse events (severe hypoglycemia and ketoacidosis).

RESULTS

The sample of 25 subjects with mean age of 33.35 ± 9.59 years, with a duration of disease, on average, of 17.1 ± 8.15 years and receiving ISCI for an average of 2.48 ± 1 08 years, obtained a decrease of 1.1% (p = 0.001) on the median value of A1c between 3 and 6 months of treatment when compared to MDI, reduction sustained throughout the analyzed period. The variation of the daily insulin requirements after pump placement was 12.75 units of insulin (p = 0.015), equivalent to a decrease of 0.20 units/kg (p = 0.023). The median of the distribution of BMI decreased 0.48 kg/m2 (p = 0.507) during CSII. The parameters of lipid profile and microalbuminuria showed no trend upward or downward after institution of CSII. The score obtained in the ADDQoL questionnaire was greater with CSII, the difference between the medians of the score distribution, before and after pump placement, was 0.056 (p = 0.92). There was a subjective perception of reduced frequency of adverse events with ISCI.

CONCLUSION

The introduction of CSII allowed optimization of metabolic control, reduction of the daily insulin requirements and achievement of a higher level of satisfaction with no change in lipid profile, no weight gain and without increasing the frequency of adverse events.

[Thyroid associated orbitopathy]

Thyroid associated orbitopathy is a clinical entity with pathogenic mechanisms not fully understood, and appears in about 90% of cases in association with hyperthyroidism of Graves' disease. Its approach involves the recognition of typical features and the exclusion of other diseases in the less common presentations. The treatment is conditioned by the determination of the activity and severity of the disease. The restoration of the euthyroid state and avoiding of hypothyroidism are essential in mitigating the progression of orbitopathy. Glucocorticoid intravenous therapy is the treatment of choice in the active phase and surgical treatment in the inactive phase. Radiotherapy and cyclosporine in combination with corticosteroids are alternatives when monotherapy is insufficient in the active phase. Treatment should be instituted in specialized centers, with ophthalmologists and endocrinologists acting in synergy to avoid consequences of delays in intervention and in optimizing therapy.

Incorporation of tocopherol acetate-containing particles in acrylic bone cement

Acrylic bone cement (BC) is used in orthopaedic surgery to anchor cemented prostheses to bone. Association of antioxidant molecules to BC may suppress reactive species injury which contributes to implant failure. Tocopherol acetate (ATA)-loaded polymethylmethacrylate (PMMA) particles (ATA(PMMA)) were prepared by single emulsion solvent evaporation technique and were incorporated into BC. An encapsulation efficiency of 84% (w/w) was obtained and drug release studies showed distinct ATA release profiles and mechanisms before and after particle incorporation into BC. Experimental data, analysed using first-order, Higuchi and Korsmeyer-Peppas models revealed that ATA was released from particles by a Fickian diffusion mechanism while a non-Fickian transport was observed upon particle incorporation in BC. There were no changes in the mechanical properties of BC specimens containing ATA(PMMA) particles, in contrast to what was observed when ATA was loaded directly into BC. Overall, ATA(PMMA) particles are potential carriers for the incorporation of an antioxidant drug into BC.

[Laboratorial diagnosis of Cushing's syndrome]

Cushing's syndrome is a diagnostic challenging endocrinous entity. Many laboratorial examinations are available for the study of these patients. Available examinations are not absolutely trustworthy for its diagnosis, so that, very often, it is necessary to conjúgate informations from different laboratory tests. In this revision one exposes the current evidence and the suggestions of different authors in the laboratorial diagnosis of Cushing's syndrome and the differential diagnosis in patients with biochemical confirmed diagnosis.

[Post-partum thyroiditis]

In the post-partum period the immune alterations are associated with the multiple autoimmune diseases relapse. After birth, immune-tolerance variation slowly disappear, and is observed a return to a normal state - after an exacerbation period - of autoimmune reactivity, during which a great increase in T cells and autoantibodies is observed. In this period - 3 to 9 months after birth - the thyroid autoimmune disease relapses or reappears. The reactivation of the immune system in the post-partum period unchains an acute phase of celular destruction which characterizes the post-partum thyroiditis.

Assessment of mother-to-child HIV-1 and HIV-2 transmission: an AIDS reference laboratory collaborative study

OBJECTIVE

A prospective study was carried out to assess HIV-1 and HIV-2 mother-to-child transmission (MTCT) rates in Portugal between 1999 and 2005 by analysing the proportion of diagnosed infected children born to HIV-positive mothers.

MATERIALS AND METHODS

Serial blood samples were collected from 1315 children at risk of HIV-1 infection, 131 children at risk of HIV-2 infection and six children at risk of both HIV-1 and HIV-2 infections attending 25 Health Institutions. HIV proviral DNA was detected by nested polymerase chain reaction (PCR) and statistical analysis was performed using spss.

RESULTS

DNA PCR using HIV-1 and HIV-2 long terminal repeat (LTR) primers amplified 92.5% and 75% of maternal HIV infections, respectively. Overall, MTCT occurred in 3.4% [95% confidence interval (CI) 2.5-4.6%] of HIV-1 and 1.5% (95% CI 0.2-5.4%) of HIV-2 mother-child pairs. A significant decrease in HIV-1 MTCT was observed with time, from 7.0% (95% CI 2.6-14.6%) in 1999 to 0.5% (95% CI 0.0-2.5%) in 2005. HIV MTCT was associated with an absence of antiretroviral therapy in infected pregnant women (P<0.0001). Of the 48 infected children (46 with HIV-1 and two with HIV-2), the schedule of blood sample collection was followed for only 26 children. In 14 (53.8%) of those 26 children the infections were diagnosed in the first sample collected before they were 48 h old, suggesting in utero transmission. Despite the national recommendations for antenatal HIV testing, a high overall proportion (22.2% for HIV-1 and 44.3% for HIV-2) of mothers did not access any MTCT prevention measures, mostly because of late diagnosis in pregnancy. A small but significant proportion of HIV-2 infection was found in mothers with no identifiable link with West Africa.

CONCLUSION

HIV-2 transmission rates are low (1.5% in this study), and this may have led to a lower uptake of interventions, but in the absence of interventions transmission does occur. HIV-1 transmission was also associated with a lack of intervention, mostly as a result of late presentation. Use of primers restricted to a single sequence led to false-negative maternal results in a significant proportion of cases. In part this may have been attributable to very low HIV DNA loads as well as primer template mismatches. HIV infection was not documented in children born to mothers with negative HIV DNA PCR results.

Thyroid diseases, dyslipidemia and cardiovascular pathology

INTRODUCTION

The relationship between thyroid hormones and lipids has long been studied, having been first described more than 70 years ago. Since then, much new information has been discovered, which justifies a reevaluation of the relationship between thyroid pathology and dyslipidemia. Thyroid hormones play an important role in regulating lipid metabolism, and thyroid dysfunction can result in lipid abnormalities which increase the risk of endothelial dysfunction, hypertension and cardiovascular disease.

METHODOLOGY

A review of the literature was carried out on the association between thyroid diseases, lipid profile and cardiovascular risk, using the Medline database and textbooks. Articles in English and Portuguese published between 1980 and 2007 were selected. Data collection took place between 2003 and 2007.

RESULTS

The increased cardiovascular risk in thyroid dysfunction is related to lipid profile, endothelial dysfunction, metabolic, hormonal and hemodynamic changes and coagulation disturbances. Because of its high prevalence in the population hypothyroidism is the principal functional disorder. Lipid anomalies associated with hypothyroidism are at least partially responsible for the increase in coronary heart disease.

CONCLUSION

The clinical benefit of treating subclinical hyperthyroidism is still the subject of debate, but treatment appears to be associated with beneficial effects on lipi d profile and cardiovascular function. Further studies are required to clarify the influence of various degrees of thyroid dysfunction in the development of atherosclerosis and cardiovascular morbidity.

Evaluation of investments in recycling centres for construction and demolition wastes in Brazilian municipalities

There are very few construction and demolition (C&D) waste recycling centres in Brazil. To encourage the building and operation of new units, data were collected and analysed relating to C&D waste management and recycling in Brazil. Based on the results of this analysis, a conceptual model is presented for conducting viability studies of future C&D waste recycling centres. Applying this model to verify the viability of private recycling centres, the results show that under current market conditions in Brazil, C&D waste recycling centres are not financially feasible based solely on revenue from the sale of processed products. Nevertheless, under the same market conditions, the recycling centres could be economically viable for public authorities depending on the particular circumstances of each municipality. The feasibility, however, depends on continuity and the production volume reached. The conceptual model, the results of its applications and the discussions about the experiences of existing centres can strongly support public authorities and private initiatives in their decision-making about investments in Brazil and in other developing countries.

Molecular Mobility in Glass Forming Fananserine: A Dielectric, NMR, and TMDSC Investigation

PURPOSE

This study was conducted to characterize the molecular mobility of supercooled fananserine and derive from this analysis the non-Arrhenius and nonexponential properties of the primary alpha-relaxation.

METHODS

The use of three investigation techniques of the molecular mobility, namely, dielectric relaxation, modulated differential scanning calorimetry, and proton nuclear magnetic resonance, allowed us to describe the dynamic properties of supercooled fananserine on a wide range of frequencies and temperatures, ranging from the melting temperature T(m) = 372 K down to the glass transition temperature T(g) = 292 K.

RESULTS

We emphasized the capacity of these three techniques to give a coherent set of information. We used the coupling-model theory to interpret the dielectric results. It allowed us to identify two relaxation processes (alpha and beta), corresponding to different molecular motions. The temperature evolution of the alpha-relaxation indicates that fananserine is a fragile glass former, as reflected by the steepness index value, m = 77. The temperature T(o) where the relaxation times diverge was also determined.

CONCLUSIONS

The description of the dielectric relaxation data in terms of the Kohlrausch-Williams-Watt relaxation function has shown the existence of an additional low-amplitude relaxation process assigned to the so-called Johari-Goldstein process. Mainly concerned by the primary alpha-process directly involved in the glass formation, we derived from this analysis the characteristic features of this process and showed that supercooled fananserine is characterized by a strongly non-Arrhenius and nonexponential behavior.

Recombination of nanometric vesicles during freeze-drying

Concentrated dispersions of nanometric lipid vesicles (mean diameter 20 nm) in water/maltose solutions have been freeze-dried and then redispersed in water, yielding again dispersions of lipid vesicles. At each stage of the freeze-drying process, the organization of the vesicles in the dispersion and their size distribution were examined through small-angle neutron scattering and gel permeation chromatography. It was found that the osmotic deswelling of the vesicles caused them to recombine into larger vesicles. A single burst of recombination events occurred when the maltose concentration in the aqueous phase rose above 100 g/L. The final vesicle population was monopopulated, with a central diameter about twice as large as that of the original dispersion.

Hydration of an amphiphilic excipient, Gelucire® 44/14

The incorporation of drugs into Gelucires has been reported to increase the dissolution rate of poorly soluble drugs, often leading to improved drug bioavailability. In pharmaceutical applications, it is important to know how the excipient interacts with the drug, and how the mixture behaves during manufacturing, storage as well as during administration. The uptake of water by an amphiphilic excipient, Gelucire 44/14, has been investigated in two ways: storage in humid air and addition of liquid water. During exposure to humid air, the uptake goes in stages that correspond to the dissolution of the components of the excipient, starting with the most hydrophilic ones: glycerol, then polyethylene glycol (PEG), PEG esters (PEG monolaurate and PEG dilaurate), and finally glycerides (trilaurin). At each stage, the remaining crystals are in equilibrium with an interstitial solution made of water and the dissolved components. In this range of hydrations, the total uptake is close to the sum of the equilibrium hydrations of the components. In the pharmaceutical formulation, the active ingredient could dissolve in the liquid phase. At larger hydrations, obtained through addition of liquid water, the state of Gelucire 44/14 differs from those of its components. Gelucire 44/14 forms a lamellar phase and this phase melts at 30 degrees C whereas the pure PEG esters form hexagonal and cubic mesophases. The cubic mesophases do not melt until the temperature exceeds 40 degrees C. At body temperature, all crystals in Gelucire 44/14 melt to an isotropic fluid as soon as the total water content exceeds 5%. Therefore the formulation of amphiphilic excipients can be optimized to avoid the formation of mesophases that impede dissolution of the excipient at body temperature.

[Thyroid diseases in pregnancy]

The thyroid diseases are more frequent in women, which is probably related to the fact that many thyroid diseases are of the autoimmune type, secondary to the effects of sexual steroids in the immunological system; although it had never been completely cleared up, it seems that estrogens and progestogens may modulate the lymphocyte differentiation as well as the induction of the autoimmune response. After delivery, the thyroid dysfunction of autoimmune type often occurs, even in women without previous history of thyroid disease. Some authors assume that the cytokines, produced by the mother, fetus or placenta, inhibit the autoimmune reaction during pregnancy. The subsequent reduction in the inhibiting cytokines, after delivery, allows the aggravation or the beginning of the autoimmune disease. Although autoimmunity is traditionally considered as a major cause for thyroid disease during pregnancy, recent studies indicate that the most common aetiology of disturbance of thyroid tests during pregnancy is the hyperthyroidism due to the inadequate production of human chorionic gonadotropin (hCG). However, from the clinical point of view, the hyperthyroidism caused by Graves' disease is the most important cause for maternal and fetal morbidity.