Epigenetic alterations in Sjögren's syndrome patient saliva.

Epigenetic mechanisms have been implicated in the pathogenesis of Sjögren's syndrome (SS). Extensive alterations in DNA methylation have been described in minor salivary gland (MSG) epithelial cells and lymphocytes derived from SS patients compared to sicca controls. In an effort to identify novel potential epigenetic markers that could prove useful in diagnosis and disease monitoring, we explored whether DNA methylation differences can also be detected in saliva from SS patients compared to sicca controls. We performed DNA methylation analysis by methylation-sensitive restriction digestion followed by quantitative real-time polymerase chain reaction of selected genomic loci in saliva samples of 16 SS patients and 10 sicca controls with negative MSG biopsy. We identified reduced DNA methylation of the imprinting control region (ICR) of the H19 locus in SS patient saliva compared to sicca controls. Levels of saliva H19 ICR methylation were negatively correlated with C4 serum complement levels. Consistent with the reduced methylation of the ICR, H19 RNA levels were increased in SS patient peripheral blood mononuclear cells (PBMCs), while no significant change was observed in MSG H19 RNA levels compared to sicca controls. Our findings support that H19 ICR methylation could be a useful molecular epigenetic marker in monitoring patients with SS, highlighting saliva as a valuable biological sample in SS research and clinical practice. The role of H19 in SS pathogenesis remains to be addressed.

The role of thrombospondin-1 in the pathogenesis of antiphospholipid syndrome.

OBJECTIVE: Antiphospholipid syndrome (APS) is an acquired thrombophilia characterized by recurrent thrombosis and/or pregnancy morbidity, in the presence of antibodies to ß2 glycoprotein-I (ß2GPI), prothrombin or Lupus anticoagulant (LA). Anti-ß2GPI antibodies recognize complexes of ß2GPI dimers with CXCL4 chemokine and activate platelets. Thrombospondin 1 (TSP-1) is secreted by platelets and exhibits prothrombotic and proinflammatory properties. Therefore, we investigated its implication in APS. METHODS: Plasma from APS patients (n = 100), Systemic Lupus Erythematosus (SLE) (n = 27) and healthy donors (HD) (n = 50) was analyzed for TSP-1, IL-1ß, IL-17A and free active TGF-ß1 by ELISA. Human Umbilical Vein Endothelial Cells (HUVECs) and HD monocytes were treated with total HD-IgG or anti-ß2GPI, ß2GPI and CXCL4 and CD4+ T-cells were stimulated by monocyte supernatants. TSP-1, IL-1ß, IL-17A TGF-ß1 levels were quantified by ELISA and Real-Time PCR. RESULTS: Higher plasma levels of TSP-1 and TGF-ß1, which positively correlated each other, were observed in APS but not HDs or SLE patients. Patients with arterial thrombotic events or those undergoing a clinical event had the highest TSP-1 levels. These patients also had detectable IL-1ß, IL-17A in their plasma. HD-derived monocytes and HUVECs stimulated with anti-ß2GPI-IgG-ß2GPI-CXCL4 secreted the highest TSP-1 and IL-1ß levels. Supernatants from anti-ß2GPI-ß2GPI-CXCL4 treated monocytes induced IL-17A expression from CD4+ T-cells. Transcript levels followed a similar pattern. CONCLUSIONS: TSP-1 is probably implicated in the pathogenesis of APS. In vitro cell treatments along with high TSP-1 levels in plasma of APS patients suggest that high TSP-1 levels could mark a prothrombotic state and an underlying inflammatory process.

Customized compared to population-based centiles for detecting term small for gestational age infants in Greece.

BACKGROUND: Applying customized centiles may improve the accuracy of detecting small for gestational age (SGA) infants; however, the evidence is inconclusive whether adjusted centiles are more sensitive in identifying infants at increased risk of morbidity. We aimed to examine the validity of customized centiles in a Greek cohort and evaluate their performance compared to population-based centiles in predicting infants at risk of increased morbidity. METHODS: We prospectively recorded the neonatal and maternal characteristics of singleton, low-risk, term infants over a year. Infants were defined as SGA if their birth weight was under the tenth centile, classified both by population-based centiles and customized centiles, adjusted for maternal and innate factors. We performed a comparative analysis utilizing linear regression analysis and calculating the receiver operating characteristics (ROC) curves. RESULTS: Overall 657 infants were identified. Population-based centiles detected 42 (6 %) SGA infants, while customized centiles 80 (12 %). Perinatal morbidity was associated with an odds ratio of 1.02 with customized centiles [95 % confidence interval (CI): 1.01-1.04] and with an odds ratio of 1.02 with population-based centiles (95 % CI: 1.02-1.02). In predicting perinatal morbidity, no significant difference was detected between customized centiles [area under the ROC curve 0.773 (95 % CI: 0.699-0.847)] and population-based centiles [area under the ROC curve 0.737 (95 % CI: 0.662-0.813)] (p =0.272). CONCLUSIONS: Customized centiles provided increased accuracy in comparison to the population-based centiles in detecting SGA term infants. However, customized centiles had no better impact on predicting a poor perinatal outcome. HIPPOKRATIA 2020, 24(3): 133-137.

West Nile Virus infection triggering autoimmune encephalitis: Pathophysiological and therapeutic implications.

BACKGROUND: A contributing factor in triggering autoimmune phenomena is pathogen infections. Here we describe a case that expands the spectrum of infection-associated autoimmune encephalitis and discuss plausible pathogenetic mechanisms. DESIGN: Case report and in silico analysis. RESULTS: A patient with West Nile Virus infection developed autoimmune encephalitis with positive anti-glycine receptor antibodies. Combination therapy with corticosteroids and intravenous immunoglobulin resulted in the resolution of encephalitis signs and symptoms. An in silico analysis unveiled certain sequence similarities between viral antigens and receptor sequence fragments suggesting a molecular mimicry autoimmunization process. CONCLUSIONS: Our case indicates that West Nile Virus infections can trigger autoimmune encephalitis. Our finding expands the spectrum of autoimmune conditions that can develop following an infection. Whether the autoimmunization process is due to molecular mimicry or due to the expansion of natural autoantibody clones merits further investigation.

Differential CpG methylation of the promoter of interleukin 8 and the first intron of tissue factor in Antiphospholipid syndrome.

BACKGROUND: Antiphospholipid syndrome (APS) is an autoimmune thrombophilia characterized by recurrent thromboembolism and/or pregnancy morbidity in the presence of Antiphospholipid antibodies, mainly anti-ß2 glycoprotein I (anti-ß2GPI). The autoantibodies lead to monocyte and endothelial cell activation and subsequent secretion of tissue factor (F3) and proinflammatory cytokines, like interleukins 6 (IL6) and 8 (IL8). The etiology of the syndrome remains largely unknown, with the contribution of environmental, genetic and epigenetic factors considered significant. PURPOSE: We aimed to identify epigenetic changes and factors potentially implicated in the pathophysiology of APS. To this end, we compared DNA methylation levels of the IL8 and F3 genes between healthy donors (HDs) and APS patients, using whole blood as a source. RESULTS: Methylation was significantly reduced in the IL8 promoter and significantly increased in the F3 gene body in APS patients compared to HDs and correlated with specific clinical parameters. In an ex vivo model partially mimicking APS, stimulation of monocytes with a mixture of ß2GPI, anti-ß2GPI and CXCL4 also induces DNA methylation changes in the above genes, along with increase of their expression. Stimulation of human umbilical vein endothelial cells (HUVECs) with the same mixture also results in transcriptional upregulation of epigenetic factors, including MΕCP2, DNMT3, TET1, HDAC9 and ARID5B. CONCLUSIONS: The above data support that epigenetic alterations could be implicated in the pathophysiology of APS and prompt further investigation of their potential diagnostic or therapeutic utility.

Identification of a homozygous deletion of the NEU1 gene in a patient with type II sialidosis presenting isolated fetal ascites and central nervous system hypoplasia.

BACKGROUND: Mutation of the NEU1 sialidase gene is the etiology of sialidosis, a storage disorder with a plethora of systemic manifestations ranging from ocular abnormalities, bone pathologies, and ataxia (sialidosis type I) to mental decline and infantile death (sialidosis type II). Non-immune hydrops fetalis and isolated ascites are the most severe forms of sialidosis type II that manifests itself prenatally. CASE REPORT: For the first time, we report congenital sialidosis with homozygous pathogenic deletion of the entire NEU1 gene in a Greek neonate with hydrops fetalis, isolated ascites, central nervous system hypoplasia, and lethal progression. Genetic characterization of the patient showed one previously unreported deletion in the NEU1 gene. CONCLUSION: Sialidosis type II should be considered in the differential diagnosis of neonatal hydrops fetalis of no immune causality or isolated fetal ascites. Genetic studying of the patient and the family by carrier detection is crucial to prevent missed diagnoses, while genetic counseling for following pregnancies is imperative. HIPPOKRATIA 2019, 23(4): 169-171.

Repair of Postoperative Abdominal Hernia in a Child with Congenital Omphalocele Using Porcine Dermal Matrix.

Introduction. Incisional hernias are a common complication appearing after abdominal wall defects reconstruction, with omphalocele and gastroschisis being the most common etiologies in children. Abdominal closure of these defects represents a real challenge for pediatric surgeons with many surgical techniques and various prosthetic materials being used for this purpose. Case Report. We present a case of repair of a postoperative ventral hernia occurring after congenital omphalocele reconstruction in a three-and-a-half-year-old child using an acellular, sterile, porcine dermal mesh. Conclusion. Non-cross-linked acellular porcine dermal matrix is an appropriate mesh used for the reconstruction of abdominal wall defects and their postoperative complications like large ventral hernias with success and preventing their recurrence.

Investigating the role of Natural Killer T-cells in Gram negative infections of patients with type 2 diabetes mellitus.

BACKGROUND: Invariant Natural Killer T (iNKT) cells belong to innate immunity and combine T-cell receptor specificity with Natural Killer surface markers. They can produce cytokines immediately after stimulation and direct immunity to either Th1 or Th2 cytokine production. iNKT cells participate in a variety of immune responses, such as microbial infections, autoimmunity, and cancer. Type 2 Diabetes Mellitus (T2DM) has been associated with activated innate immunity and certain cytokine profile during microbial infections. This study aimed to evaluate whether iNKT cells have a role in the immune response of T2DM patients during infections with gram-negative bacteria. METHOD: The T2DM group consisted of patients (n =11) who had a diagnosis of T2DM for at least six months and febrile illness for three days, while the control group consisted of patients (n =11) who had not T2DM, but were febrile for three days. All patients were infected by gram-negative bacteria. Physical examination was performed, and peripheral blood was drawn on days three and six of febrile illness. Flow cytometry was utilized for iNKT cell identification with monoclonal antibodies Phycoerythrin (PE) - Cyanin (CY) 5 anti-Human CD3, Fluorescein isothiocyanate (FITC) anti-Human CD4, PE anti-human invariant NKT T-Cell Receptor. For intracellular staining, we used Alexa Fluor anti-Human interferon-γ (IFN-γ) and Allophycocyanin (APC) anti-human interleukin-4 (IL-4). The variables processed were: CD3+IL-4+iNKT+ , CD4+IL-4+iNKT+, CD3+IFNγ+iNKT+, CD4+IFNγ+iΝΚΤ+, CD3+iNKT+, CD4+iNKT+ ,CD3+IL4+, CD4+IL-4+, CD3+IFNγ+, CD4+IFNγ+ on days three and six of febrile illness (CD3+, CD4+: T lymphocyte surface markers, iNKT+: invariant Natural Killer T- Cell Receptor, IL4+: interleukin 4, IFNγ+: interferon γ). RESULTS: Comparisons between T2DM patients and controls revealed no statistically significant difference in any of the study's variable. Regarding within T2DM patients comparisons CD4+IL4+iNKT+, CD3+IL4+iNKT+, CD4+IFN+iNKT+, CD3+IFN+iNKT+, and CD3+iNKT+  decreased, whereas CD3+IL4+ was increased at day six compared to day three. Within control group CD4+IL4+iNKT+, CD3+IL4+iNKT+, and CD3+iNKT+ were decreased, whereas CD4+IFN+, CD3+IFN+ were increased at day six compared to day three. CONCLUSION: The absence of statistical difference between T2DM patients and controls implies that the role of iNKT cells is virtually the same in both groups of patients during the course of gram-negative infections and that there is no numerical variance of this cell population between the two groups. Despite the small sample size, we notice that all iNKT parameters (both IL4/IFNγ) are suppressed in the T2DM group during the later phase, but only those concerning IL4+iNKT+ in the control group, suggesting that IFNγ production remains elevated in the controls. A compensatory anti-inflammatory type-response could provide an explanation for the prevalence of IL4 production during the later phase of infection in T2DM and the sustained production of IFNγ in controls. Hippokratia 2015; 19 (3): 231-234.

Assessment of lung ventilation in infants with respiratory distress syndrome using electrical impedance tomography.

AIM: The aim of the present study was to determine immediate changes of global and regional lung function after exogenous surfactant administration in mechanically ventilated infants with respiratory distress syndrome (RDS) using electrical impedance tomography (EIT) measurements. MATERIALS AND METHODS: A prospective study was conducted in a Neonatal Intensive Care Unit at a university hospital. Seventeen preterm infants (<12 hours old) suffering from RDS were included in this study. Interventions taken were low-pressure recruitment maneuver, surfactant administration and minimal adjustments in ventilator settings. Repeated EIT measurements (401 in total) were performed before and after (15 min - 30 min) surfactant administration. Global lung function changes were assessed with two markers, namely absolute resistivity (AbsR) and normalized impedance change (ΔZ); redistribution of regional lung ventilation was assessed as well. Airway pressure and arterial blood gases were recorded. RESULTS: Surfactant administration resulted in a statistically significant increase of both the AbsR and ΔZ markers. Moreover, there was a ventilation shift towards dorsal - dependent lung areas with less asymmetry in the right-to-left air distribution. CONCLUSIONS: Surfactant administration in the recruited lung with RDS modifies regional ventilation, as assessed by EIT, contributing to a more homogeneous air distribution. Furthermore, significant changes in EIT markers reflect improvement of global lung function after surfactant administration.

Comparative efficacy of exenatide versus insulin glargine on glycemic control in type 2 diabetes mellitus patients inadequately treated with metformin monotherapy.

PURPOSE: Comparative efficacy of exenatide versus insulin glargine primarily on glucemic control, and secondarily on body mass index (BMI), lipid profile and blood pressure, in type 2 diabetes mellitus (T2DM) patients suboptimally treated with metformin monotherapy. MATERIAL/METHODS: Forty-seven inadequately treated T2DM patients on metformin assigned to exenatide (n=18) or insulin glargine (n=29) for 26 weeks. Glycosylated hemoglobin (HbA1c), serum lipids, BMI, systolic and diastolic blood pressure, and adverse events, including episodes of hypoglycemia and gastrointestinal symptoms, were recorded. RESULTS: Either treatment had a similar favorable mean reduction in HbA1c. However, more patients in exenatide group achieved HbA1c ≤ 7% at the 26th week compared with insulin glargine group (p=0.036). Insulin glargine group had significantly more episodes of hypoglycemia compared with exenatide group (p=0.039). Gastrointestinal adverse events were non-significantly higher in the exenatide group. A significantly greater BMI reduction was observed in exenatide group, whereas ΒΜΙ was not altered in insulin glargine group. Total and LDL cholesterol (p=0.012), and triglycerides (p=0.016) significantly decreased, whereas HDL cholesterol increased (p=0.021) in the exenatide group, whereas only total cholesterol decreased in insulin glargine group. Changes in systolic and diastolic blood pressure were insignificant in both groups. CONCLUSIONS: Exenatide provided similar reduction in HbA1c, but fewer episodes of hypoglycemia, compared with insulin glargine. Exenatide had also a favorable effect on weight loss, although more gastrointestinal adverse events. Exenatide may provide a justified alternative in second line treatment of T2DM, but more trials are required to elucidate its long-term safety and cost-effectiveness.

Glutathion-S-Transferase P1 polymorphisms association with broncopulmonary dysplasia in preterm infants.

BACKGROUND: Oxidative stress, characterized by the excretion of pre-oxidative and anti-oxidative proteases, has a key role in the pathogenesis of bronchopulmonary dysplasia (BPD). One of the many host anti-oxidant enzymes is glutathione-S-transferase P1 (GSTP1), with three polymorphic alleles having been identified: homozygous ile, heterozygous ile/val and homozygous val isomorph. The aim of this study was to examine the genetic predisposition to BPD in the GSTP1 polymorphisms. METHODS: A prospective case-control study was carried out in the 2nd Neonatal Intensive Care Unit of Aristotle University in Thessaloniki, Greece during 2008. The genetic polymorphisms of GSTP1 in 28 preterms <32 weeks gestational age (GA) with BPD compared to 74 controls (33 preterms without BPD and 41 healthy terms) were examined. RESULTS: The homozygous ile isomorph was predominant in all groups (preterms with BPD: 82%, preterms without BPD: 70%, healthy terms: 78%), followed by the heterozygous ile/val (14%, 18% and 20% respectively) and the homozygous val isomorph (4%, 12% and 2% respectively). The homozygous ile isomorph was also identified in the majority of preterms with mild (80%), moderate (100%) and severe (73%) BPD. The GSTP1 genetic distribution did not differ between the groups and GSTP1 polymorphisms were not associated with the severity of BPD. CONCLUSIONS: This study could not confirm an association between GSTP1 polymorphisms and the development of BPD or the severity of the disease.

Glycemia and cardiovascular risk: challenging evidence based medicine.

Optimal glycemic control is well known to reduce effectively the risk of micro vascular complications both in type 1 and type 2 diabetes mellitus. However the role of glycemic control in decreasing the risk of myocardial infarction and ischemic stroke, the leading causes of death in patients with diabetes, has been so far controversial. In this review, based on data recently reported from large interventional studies, we discuss the possible causal relationship between glycemia and cardiovascular outcomes in type 1 and type 2 diabetes. Strict glycemic control right from the diagnosis of the disease may be effective in reducing long term incidence of cardiovascular (CV) disease in both T1 and T2 diabetics. Nevertheless such a strategy could be potentially harmful for T2 diabetics with long duration of sub optimal glycemic control and already established CV complications. Treatment targets in these patients should be individualized taking into account other aspects of glycemic control and diabetes complications such as hypoglycemia and autonomic neuropathy.

Identification of a mutation in the MTM1 gene, associated with X-linked myotubular myopathy, in a Greek family.

X-linked myotubular myopathy (XLMTM) is a rare congenital myopathy, usually characterized by severe hypotonia and respiratory insufficiency at birth, in affected, male infants. The disease is causally associated with mutations in the MTM1 gene, coding for phosphatase myotubularin. We report a severe case of XLMTM with a novel mutation, at a donor splicing site (c.1467+1G) previously associated with severe phenotype. The mutation was also identified in the patient's mother, providing an opportunity for sound genetic counseling.

Continuous subcutaneous insulin infusion versus multiple daily injections.

BACKGROUND AND AIM: Continuous Subcutaneous Insulin Infusion (CSII) and Multiple Daily insulin Injections (MDI) are both strategies aiming to achieve a tight glycemic and metabolic control. However, the choice between them remains controversial. The aim of the present study was to compare the efficacy of MDI (three or more injections daily) with CSII on glycemic control in patients with Type 1 Diabetes Mellitus and assess satisfaction from treatment in the CSII group. MATERIAL AND METHODS: Seventeen patients with Type 1 Diabetes Mellitus on CSII (previously on MDI) and 17 patients on MDI, matched for age, gender, BMI and duration of diabetes, were retrospectively studied. Glucosylated Hemoglobin A1c (HbA1c), frequency of hypoglycaemias (assessed as self reported episodes), BMI and total units of insulin per day were evaluated at baseline and after 6 months in both groups. CSII group completed a questionnaire concerning motive for treatment selection, advantages, deficiencies and inconvenience at the end of the study. Satisfaction from treatment was assessed with a scale from 0 to10. RESULTS: CSII group had more hypoglycaemic episodes at baseline than MDI group (16.2+/-2.8 vs 2.8+/-1.3, p<0,001). HbA1c (8.4+/-0.5 before vs 7.3+/-0.4 after, p<0.05) and total hypoglycaemic episodes per month (16.2+/-2.8 before vs 8.7+/-2.3 after, p<0.05) significantly decreased in CSII group 6 months after baseline. On the contrary, total hypoglycaemic episodes per month were increased in MDI group (2.8+/-1.3 before vs 10.8 +/-2,6 after, p<0.05) in order to maintain HbA1c levels. No significant differences were observed in BMI in both groups. Total insulin demands were reduced in the CSII group (49.4+/-3.3 before vs 39.0+/-4.6 after, p<0.05) and remained unchanged in MDI group. None of the patients discontinued CSII therapy, while overall satisfaction rate in this group was high. The main motive for CSII selection was frequent hypoglycaemic episodes and glucose fluctuations (10/17). The majority of patients expressed their wish for incorporating glucose trend indicator and/or continuous glucose measurement into pump and reducing pump size (15/17). Most commonly stated advantage was improved flexibility, followed by greater freedom and decreased sense of physical restrictions (10/17). Inconvenience mainly derived from alarm malfunction and catheter or needle occlusion and was reported from a minority of patients (4/17). CONCLUSION: CSII group reported more hypoglycaemias than MDI group at baseline but 6 months later had significantly less hypoglycaemic events, while on the contrary, MDI group 6 months after baseline had more frequent and more severe hypoglycaemias. Although baseline hypoglycaemias are not equal between the two groups, we can assume that CSII group achieved less hypoglycaemic events along with significant reduction in HbA1c while utilising less insulin units.

HDAC3: taking the SMRT-N-CoRrect road to repression.

Known histone deacetylases (HDACs) are divided into different classes, and HDAC3 belongs to Class I. Through forming multiprotein complexes with the corepressors SMRT and N-CoR, HDAC3 regulates the transcription of a plethora of genes. A growing list of nonhistone substrates extends the role of HDAC3 beyond transcriptional repression. Here, we review data on the composition, regulation and mechanism of action of the SMRT/N-CoR-HDAC3 complexes and provide several examples of nontranscriptional functions, to illustrate the wide variety of physiological processes affected by this deacetylase. Furthermore, we discuss the implication of HDAC3 in cancer, focusing on leukemia. We conclude with some thoughts about the potential therapeutic efficacies of HDAC3 activity modulation.