Exploring factors influencing depression among Polish nurses during the COVID-19 pandemic

Objectives

The COVID-19 pandemic has been recognized as an international public health emergency. The aim of our study was to identify contributors to nurses' depression.

Methods

This survey-based study was conducted in the Pomeranian Medical University Hospital no. 1 in Szczecin and involved 207 nurses. The following standardized research instruments were applied: the World Assumptions Scale, the Athens Insomnia Scale, the Impact of Event Scale - Revised, the Patient Health Questionnaire-9, the Generalized Anxiety Disorder, the Perceived Stress Scale, and a questionnaire of our own authorship.

Results

The study showed that 72.95% of the subjects experienced severe stress, and 40.58% suffered from insomnia. In addition, 65.7% of the respondents had anxiety symptoms of varying degrees of severity, and 62.8% had depressive symptoms of mild to severe severity. The mean score on the IES-R scale, reflecting a psychological impact of the COVID-19 pandemic, was 34.25. The COVID-19 pandemic affected the psychological health of medical staff, particularly through increased stress and anxiety symptoms. Anxiety levels and insomnia significantly affect the prevalence of depression among nurses.

Conclusion

The COVID-19 pandemic has been recognized as an international public health emergency. The COVID-19 pandemic affected the psychological health of medical staff, particularly through increased stress and anxiety symptoms. It is important to conduct further research after the COVID-19 pandemic has ended.

THADA, SDHAF4, and MACF1 Gene Polymorphisms and Placental Expression in Women with Gestational Diabetes

Gestational diabetes mellitus (GDM) is a metabolic disorder in pregnant women leading to various complications. Consequently, factors predisposing its development are being sought. Previous studies have shown that the pathogenesis of GDM is similar to that of type 2 diabetes, and it is therefore thought that the two diseases may have a common genetic basis. The aim of this study was to examine the associations between thyroid adenoma-associated (THADA) rs7578597 T>C, succinate dehydrogenase complex assembly factor 4 (SDHAF4) rs1048886 A>G, and microtubule-actin crosslinking factor 1 (MACF1) rs2296172 A>G gene polymorphisms and the risk of GDM development as well as selected clinical parameters in women with GDM. We also examined the expression of these genes in the placenta of women with and without GDM in association with clinical parameters. This case-control study included 272 pregnant women with GDM and 348 pregnant women with normal glucose tolerance. There were no statistically significant differences in the distribution of the THADA rs7578597 T>C, SDHAF4 rs1048886 A>G, and MACF1 rs2296172 A>G gene polymorphisms between pregnant control women and women with GDM. The associations between clinical parameters such as body mass before pregnancy, body mass at birth, body mass increase during pregnancy, BMI before pregnancy, BMI at birth, BMI increase during pregnancy, glycated hemoglobin (HbA1c), daily insulin requirement, childbirth time, and newborn body mass and APGAR score, and the THADA rs7578597 T>C, SDHAF4 rs1048886 A>G, and MACF1 rs2296172 A>G genotypes were statistically non-significant. We only observed lower values of body mass before pregnancy and body mass at birth in women with the SDHAF4 rs1048886 AG genotype in comparison with AA genotype carriers. There was no statistically significant difference in the expression of THADA, SDHAF4, and MACF1 genes in the placenta between women with GDM and healthy women. There were also no statistically significant correlations between THADA, SDHAF4, and MACF1 gene expression in the placenta and clinical parameters. The results of our study suggest that THADA rs7578597 T>C, SDHAF4 rs1048886 A>G, and MACF1 rs2296172 A>G gene polymorphisms are not significant factors associated with GDM onset. In addition, SDHAF4 rs1048886 A>G may be associated with body mass before pregnancy and body mass at birth in pregnant women.

Analysis of the laboratory results of the patients enrolled in the Nutritional Therapy Program

OBJECTIVE

Nutritional treatment is an integral part of patient management, as meeting nutritional needs significantly contributes to improving treatment outcomes and reducing complications and length of hospitalization. The aim of this study was to analyze the laboratory results of the patients enrolled in the Nutritional Therapy Program.

PATIENTS AND METHODS

This study involved 103 subjects, aged 18-88. It was based on analysis of medical documentation of patients under the care of the Enteral Nutrition Clinic. Nutritional status was assessed by biochemical tests (urea, creatinine, AST, ALT, ALP, CRP, total cholesterol, triglycerides, INR, Na, K, Cl, Mg, Ca, P, Fe, total protein, albumin, and fasting glucose).

RESULTS

After six and twelve months, the groups with malnutrition and neurological diseases had higher levels of erythrocytes and albumin, and significantly lower CRP. The mean glucose level after six months was significantly lower compared to the first measurement, and a downward trend was observed. Calcium showed an upward trend. In cancer patients, a decline in erythrocytes was observed after six months compared to the initial measurement.

CONCLUSIONS

There were significant differences in the results of laboratory tests between patients with cancer and those with malnutrition and neurological diseases. These were mainly lower levels of lymphocytes and glucose, and higher levels of platelets and CRP. Furthermore, the greatest effect of nutritional treatment was observed in patients with malnutrition and neurological diseases.

The effect of vitamin D levels on lipid, glucose profiles and depression in perimenopausal women

OBJECTIVE

Vitamin D deficiency is a significant problem that affects the population living in most countries. This issue is independent by place of residence, sex, age or skin color. It is mainly influenced by the environment we live in and by an unhealthy lifestyle, including bad eating habits. The aim of this study was to evaluate lipid profile, glucose levels, and vitamin D levels, considering sociodemographic variables, smoking and alcohol consumption in perimenopausal women. Depressive mood was also assessed considering sociodemographic variables and vitamin D levels.

PATIENTS AND METHODS

The study was conducted on a group of 191 women and performed in two stages. The first of them was carried out using a diagnostic survey with the use of a technique questionnaire. The applied research instruments were the author's questionnaire (concerning sociodemographic and selected medical data), and the Beck Depression Inventory. The second stage of the study involved the collection of peripheral blood from each respondent, in order to determine lipid profile, glycemia and serum vitamin D levels.

RESULTS

The age of the female respondents ranged from 45 to 65 years, mean age was 53.1 ± 5.37 years, median 53 years. Vitamin D levels were below normal in 78%; 77% had elevated total cholesterol levels; 91.6% of the respondents had high density lipoprotein (HDL) cholesterol levels within the normal range; 64.4% was characterized by too high (low-density lipoprotein) LDL cholesterol, and 84.8% of the women showed normal triglyceride levels. Among the respondents, 91.1% had normal glycemic levels. Analysis of the collected data showed a weak negative correlation between serum vitamin D levels and the levels of total cholesterol (rho=-0.14; p=0.05), LDL cholesterol (rho=-0.16; p=0.026), and triglycerides (rho=-0.22; p=0.002). Only in the case of HDL cholesterol (p=0.067), there was no statistically significant correlation. There were also no statistically significant correlations between serum vitamin D levels and glycemia or severity of depression.

CONCLUSIONS

1. The majority of the women did not manifest depressive disorders. Of all factors analyzed, only education was associated with the severity of depressiveness. 2. Smoking adversely affected serum vitamin D levels in the studied women. 3. The cessation of menstruation affected carbohydrate metabolism and vitamin D levels. Blood glucose levels increased with the age of the studied women. 4. Relationships were found between the levels of vitamin D and the levels of total cholesterol, LDL cholesterol, and triglycerides. Therefore, it is important to maintain normal vitamin D levels.

PPARG, TMEM163, UBE2E2 and WFS1 Gene Polymorphisms Are Not Significant Risk Factors for Gestational Diabetes in the Polish Population

Gestational diabetes mellitus (GDM) is a common disorder that occurs in pregnant women, leading to many maternal and neonatal complications. The pathogenesis of GDM is complex and includes risk factors, such as: age, obesity, and family history of diabetes. Studies have shown that genetic factors also play a role in the pathogenesis of GDM. The present study investigated whether polymorphisms in the PPARG (rs1801282), TMEM163 (rs6723108 and rs998451), UBE2E2 (rs6780569), and WFS1 (rs4689388) genes are risk factors for the development of GDM and whether they affect selected clinical parameters in women with GDM. This study included 204 pregnant women with GDM and 207 pregnant women with normal glucose tolerance (NGT). The diagnosis of GDM was based on a 75 g oral glucose tolerance test (OGTT) at 24–28 weeks gestation, according to the International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria. There were no statistically significant differences in the distribution of polymorphisms studied between women with GDM and pregnant women with normal carbohydrate tolerance, which suggests that these polymorphisms are not risk factors for GDM. We also examined the associations between studied gene polymorphisms and clinical parameters: fasting glucose, daily insulin requirement, body mass before pregnancy, body mass at birth, body mass increase during pregnancy, BMI before pregnancy, BMI at birth, BMI increase during pregnancy, new-born body mass, and APGAR score in women with GDM. We observed lower BMI values before pregnancy and at birth in women with PPARG rs17036160 TT genotype. The results of this study suggest that the PPARG (rs1801282), TMEM163 (rs6723108 and rs998451), UBE2E2 (rs6780569), and WFS1 (rs4689388) gene polymorphisms are not significant risk factors for GDM development in the Polish population and do not affect the clinical parameters in women with GDM; only rs1801282 of the PPARG gene may influence BMI values in women with GDM.

Assessment of Psychosocial Functioning of Polish Nurses during COVID-19 Pandemic

(1) The COVID-19 pandemic has significantly affected the psychological well-being of people around the world. The aim of this study was to assess the levels of psychological distress of nurses (anxiety, depression, stress, insomnia) in relation to sociodemographic variables and psychosocial variables: self-assessment of health, quarantine, psychological support, presence of chronic diseases and the Impact of Events Scale (IES-R). (2) A total of 207 nurses working with COVID-19 patients at the Independent Public Clinical Hospital No. 1 of the Pomeranian Medical University in Szczecin participated in the study. The study was conducted with the diagnostic survey method, using the Athens Insomnia Scale, the Generalized Anxiety Disorder questionnaire, the Impact of Event Scale—Revised, the Patient Health Questionnaire-9, The Perceived Stress Scale and a questionnaire of our authorship. (3) Among the respondents, 40.58% suffered sleep disturbance, 36.71% had mild anxiety, 71.95% had high stress according to the PSS-10 and 31.88% had depression according to the PHQ-9. The study observed that the chances of insomnia decreased with the age of the respondents. Moreover, the form of employment of nurses significantly affected the levels of depression, anxiety and stress. (4) Education, gender and age were variables that significantly affected the severity of anxiety, depression and insomnia in the surveyed nurses working with patients with COVID-19.

ADCY5, CAPN10 and JAZF1 Gene Polymorphisms and Placental Expression in Women with Gestational Diabetes

Gestational diabetes mellitus (GDM) is carbohydrate intolerance that occurs during pregnancy. This disease may lead to various maternal and neonatal complications; therefore, early diagnosis is very important. Because of the similarity in pathogenesis of type 2 diabetes and GDM, the genetic variants associated with type 2 diabetes are commonly investigated in GDM. The aim of the present study was to examine the associations between the polymorphisms in the ADCY5 (rs11708067, rs2877716), CAPN10 (rs2975760, rs3792267), and JAZF1 (rs864745) genes and GDM as well as to determine the expression of these genes in the placenta. This study included 272 pregnant women with GDM and 348 pregnant women with normal glucose tolerance. The diagnosis of GDM was based on a 75 g oral glucose tolerance test (OGTT) at 24–28 weeks gestation, according to International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria. There were no statistically significant differences in the distribution of the ADCY5 gene (rs11708067, rs2877716) and CAPN10 gene (rs2975760, rs3792267) polymorphisms between pregnant women with normal carbohydrate tolerance and pregnant women with GDM. We have shown a lower frequency of JAZF1 gene rs864745 C allele carriers among women with GDM CC + CT vs. TT (OR = 0.60, 95% CI = 0.41–0.87, p = 0.006), and C vs. T (OR = 0.75, 95% CI = 0.60–0.95, p = 0.014). In addition, ADCY5 and JAZF1 gene expression was statistically significantly increased in the placentas of women with GDM compared with that of healthy women. The expression of the CAPN10 gene did not differ significantly between women with and without GDM. Our results indicate increased expression of JAZF1 and ADCY5 genes in the placentas of women with GDM as well as a protective effect of the C allele of the JAZF1 rs864745 gene polymorphism on the development of GDM in pregnant women.

Comparative Analysis of Global Gene Expression and Complement Components Levels in Umbilical Cord Blood from Preterm and Term Neonates: Implications for Significant Downregulation of Immune Response Pathways related to Prematurity

Background: Preterm birth is the most frequent cause of neonatal death, but its aetiology remains unclear. It has been suggested that the imbalance of immunological mechanisms responsible for maintaining pregnancy is contributing to preterm birth pathogenesis. We aimed to investigate global gene expression and the levels of several complement system components in umbilical cord blood samples from preterm neonates and compare them to term newborns. We sought to examine how differentially expressed genes could affect various immune-related pathways that are believed to be crucial factors in preterm birth. Material and methods: We enrolled 27 preterm infants (<37 weeks GA) and 52 term infants (>37 weeks GA), from which umbilical cord blood samples were collected. From these samples, peripheral blood mononuclear cells were isolated and subsequent RNA isolation was performed. We used Affymetrix Human Gene 2.1 ST Array Strip for microarray experiment and DAVID resources for bioinformatics analysis of the obtained data. Concentrations of C2, C3a, C5/C5a, C9, FactorD, Properdin were measured in umbilical cord blood plasma samples using multiplex fluorescent bead-based immunoassays using Luminex technology. Results: The levels of C3a and C5/5a were significantly elevated in preterm neonates compared to term babies, whereas C9 concentration was evidently increased in term infants. The expression of 250 genes was upregulated at least 2-fold and 3781 genes were downregulated at least 2-fold in preterm neonates in comparison with term infants. Functional annotation analysis revealed that in preterm infants in comparison to term babies there was a significant downregulation of genes encoding several Toll-like receptors, interleukins and genes involved in major signalling pathways (e.g. NF-κB, MAPK, TNF, Notch, JAK) and vital cellular processes (e.g. intracellular signal transduction, protein ubiquitination, protein transport, RNA splicing, DNA-templated transcription). Conclusions: Preterm birth results in immediate and long-term complications. Our results indicate that infants born prematurely show significant differences in complement components concentration and a downregulation of over 3,000 genes, involved mainly in various immune-related pathways, including innate immune response, phagocytosis and TLR function, when compared to full-term babies. Further studies on larger cohorts are needed to elucidate the role of immunity in prematurity.

IL-1β and IL-10 gene polymorphisms in women with gestational diabetes

AIMS

Gestational diabetes (GDM) is carbohydrate intolerance occurring in pregnant women. In the GDM pathogenesis, the low-grade inflammation plays a significant role. Various inflammatory mediators are considered to be risk factors leading to GDM development including cytokines. Studies suggest that some cytokines such as: IL-1β and IL-10 play an important role in GDM pathogenesis. The aim of the study was to examine the associations between IL-1β rs16944, and IL-10 rs1800872 gene polymorphisms and GDM.

METHODS

This study included 204 pregnant women with GDM and 207 pregnant women with normal glucose tolerance. The diagnosis of GDM was based on a 75-g oral glucose tolerance test administered at 24-28 weeks' gestation. Among the pregnant women with GDM, 152 (75%) were treated with diet control alone throughout the pregnancy, whereas the remaining 52 (25%) were treated with diet control and insulin until delivery.

RESULTS

There were no statistically significant differences in the distribution of IL-1β rs16944 and IL-10 rs1800872 between GDM and healthy women. However among women treated with insulin, we observed the increased frequency of IL-1β rs16944 AA genotype carriers. Additionally, we observed increased daily insulin requirement in women with IL-1β rs16944 AA genotype. Moreover, women with IL-10 rs1800872 AA genotype had higher body mass and BMI before pregnancy as well as higher body mass and BMI increase during pregnancy.

CONCLUSIONS

The results of our study suggest the association between IL-1β rs16944 AA genotype and increased frequency of the need of insulin treatment as well as increased daily insulin requirement.

Autologous cord blood transfusion in preterm infants - could its humoral effect be the kez to control prematurity-related complications? A preliminary study

Umbilical cord blood (UCB), rich in stem/progenitor cells, is partially eliminated from the bloodstream during childbirth because the cord is immediately clamped. We hypothesize that transfusion of autologous UCB to premature infants after delivery could serve as an adjuvant modality for preventing the development of prematurity-related complications. We randomly enrolled 20 preterm infants born before 32 weeks of gestational age (GA), all of whom developed anemia, necessitating transfusion of red blood cells (RBCs). Two groups, matched for GA, were selected: (1) infants (n = 5) who underwent UCB transfusion once within 5 days of birth (mean ± standard deviation, 3.2 ± 1.9 days) and (2) infants (n = 15) from whom UCB was not collected (e.g., lack of consent). The latter served as controls and received allogeneic RBC transfusions (7.8 ± 3.9 days after birth). Selected prematurity-related complications were monitored. Two weeks after UCB/RBC transfusion, peripheral blood samples were collected, and the concentrations of 41 selected growth factors and their receptors were analyzed using a multiplex protein array. UCB transfusions were found to be both feasible and tolerable. Intraventricular haemorrhage was diagnosed in two of five (40%) UCB recipients, but was found in thirteen of fifteen RBC recipients (86.7%). Twenty-two plasma proteins (e.g., insulin-like growth factors, stem cell factor, epidermal growth factors) were found with significantly different concentrations in UCB recipients compared to controls. Results demonstrate safety and feasibility of UCB transfusion in a small group of very premature neonates and should be interpreted as preliminary speculation. Transfusion of UCB could induce a specific humoral effects, and this could serve as an adjuvant modality for prevention of prematurity complications.

[Outline of the history of caesarean section – from ancient times to the end of 17th Century]

Problems with the childbirth accompanied the human civilization since its beginning. From the ancient times, physicians and other people specializing in healing, tried to help women in this special moment of life. At the base of this exceptional meaning of childbirth for humans lies the fact, that if something is going wrong there are two victims - mother and the child. As a result, many times there had been very dramatic attempts of help in this the most difficult journey which in his life every man is undergoing. In this paper a comprehensive review of literature about the history of caesarean section from ancient times to the end of 17th century was done.

Clinical Evaluation of the Safety and Feasibility of Whole Autologous Cord Blood Transplant as a Source of Stem and Progenitor Cells for Extremely Premature Neonates: Preliminary Report

OBJECTIVES

This is a preliminary, single-center, prospective study in the field of autologous cord blood transplant. We investigated the feasibility, safety, and tolerability of autologous whole cord blood transplant in extremely premature infants as a potential therapeutic modality to prevent developing complications related to prematurity.

MATERIALS AND METHODS

This preliminary prospective study (ClinicalTrials.gov identifier NCT02050971) included preterm infants born at less than 32 weeks of gestational age who developed anemia because of prematurity. Infants were assigned to 2 groups: (1) those receiving an autologous cord blood transfusion within 5 days postpartum (n = 5) and (2) those who obtained only an allogeneic red blood cell transfusion when necessary (n = 9; control group). Vital measurements were performed during and after transfusion, and peripheral blood pH, hematocrit, glucose, and calcium and potassium ion levels were measured over the next 4 days.

RESULTS

Oxygen saturation was significantly increased throughout the cord blood transfusion and in the subsequent 48 hours. No significant differences were found in vital measurements, such as arterial blood pressure (mean, systolic, and diastolic) or heart rate over the first 48 hours posttransfusion. Similarly, no significant differences were found in biochemical analyses of blood with the exception of pH level. We found initial pH level to be significantly augmented in the cord blood recipient group by the first day after transplant, which remained significantly higher for next 24 hours compared with that shown in the control group.

CONCLUSIONS

Collection, preparation, and short-term storage of unfrozen cord blood are feasible for clinical use. Our results showed general safety and tolerability of the procedure of whole autologous cord blood transplant in recruited preterm newborns. However, because our study group was small, these results need to be confirmed in further investigations with a larger patient cohort.

The influence of BDNF on human umbilical cord blood stem/progenitor cells: implications for stem cell-based therapy of neurodegenerative disorders

Umbilical cord blood (UCB)-derived stem/progenitor cells (SPCs) have demonstrated the potential to improve neurologic function in different experimental models. SPCs can survive after transplantation in the neural microenvironment and indu ce neuroprotection, endogenous neurogenesis by secreting a broad repertoire of trophic and immunomodulatory cytokines. In this study, the influence of brain-derived neurotrophic factor (BDNF) pre-treatment was comprehensively evaluated in a UCB-derived lineage-negative (Lin-) SPC population. UCB-derived Lin- cells were evaluated with respect to the expression of (i) neuronal markers using immunofluorescence staining and (ii) specific (TrkB) receptors for BDNF using flow cytometry. Next, after BDNF pre-treatment, Lin- cells were extensively assessed with respect to apoptosis using Western blotting and proliferation via BrdU incorporation. Furthermore, NT-3 expression levels in Lin- cells using RQ PCR and antioxidative enzyme activities were assessed. We demonstrated neuronal markers as well as TrkB expression in Lin- cells and the activation of the TrkB receptor by BDNF. BDNF pre-treatment diminished apoptosis in Lin- cells and influenced the proliferation of these cells. We observed significant changes in antioxidants as well as in the increased expression of NT-3 in Lin- cells following BDNF exposure. Complex global miRNA and mRNA profiling analyses using microarray technology and GSEA revealed the differential regulation of genes involved in the proliferation, gene expression, biosynthetic processes, translation, and protein targeting. Our results support the hypothesis that pre-treatment of stem/progenitor cells could be beneficial and may be used as an auxiliary strategy for improving the properties of SPCs.

Humoral activity of cord blood-derived stem/progenitor cells: implications for stem cell-based adjuvant therapy of neurodegenerative disorders

Background

Stem/progenitor cells (SPCs) demonstrate neuro-regenerative potential that is dependent upon their humoral activity by producing various trophic factors regulating cell migration, growth, and differentiation. Herein, we compared the expression of neurotrophins (NTs) and their receptors in specific umbilical cord blood (UCB) SPC populations, including lineage-negative, CD34⁺, and CD133⁺ cells, with that in unsorted, nucleated cells (NCs).

Methods and Results

The expression of NTs and their receptors was detected by QRT-PCR, western blotting, and immunofluorescent staining in UCB-derived SPC populations (i.e., NCs vs. lineage-negative, CD34⁺, and CD133⁺ cells). To better characterize, global gene expression profiles of SPCs were determined using genome-wide RNA microarray technology. Furthermore, the intracellular production of crucial neuro-regenerative NTs (i.e., BDNF and NT-3) was assessed in NCs and lineage-negative cells after incubation for 24, 48, and 72 h in both serum and serum-free conditions. We discovered significantly higher expression of NTs and NT receptors at both the mRNA and protein level in lineage-negative, CD34⁺, and CD133⁺ cells than in NCs. Global gene expression analysis revealed considerably higher expression of genes associated with the production and secretion of proteins, migration, proliferation, and differentiation in lineage-negative cells than in CD34⁺ or CD133⁺ cell populations. Notably, after short-term incubation under serum-free conditions, lineage-negative cells and NCs produced significantly higher amounts of BDNF and NT-3 than under steady-state conditions. Finally, conditioned medium (CM) from lineage-negative SPCs exerted a beneficial impact on neural cell survival and proliferation.

Conclusions

Collectively, our findings demonstrate that UCB-derived SPCs highly express NTs and their relevant receptors under steady-state conditions, NT expression is greater under stress-related conditions and that CM from SPCs favorable influence neural cell proliferation and survival. Understanding the mechanisms governing the characterization and humoral activity of subsets of SPCs may yield new therapeutic strategies that might be more effective in treating neurodegenerative disorders.

Increased circulating endothelial progenitor cells in patients with haemorrhagic and ischaemic stroke: the role of endothelin-1

Ischaemic stroke induces endothelial progenitor cell (EPC) mobilisation from bone marrow into peripheral blood. Circulating EPCs play an important role in post-injury regeneration of vasculature, whereas endothelial cells (ECs) have been shown to reflect endothelial damage and may be responsible for increased Endothelin-1 (ET-1) expression. We investigated herein the association between numbers of circulating ECs and EPCs, the levels of soluble factors regulating their migration and function, and the clinical outcome in patients with haemorrhagic (HS) or ischaemic stroke (IS). Sixteen patients with HS and eighteen with IS were assessed during the first 24h, day 3, and day 7 after stroke and compared them with twenty-three control subjects. We found elevated EPC and EC concentrations using flow cytometry and increase in VEGF, SDF-1, HGF, and ET-1 plasma levels by ELISA in the HS patients, while ET-1 mRNA expression in peripheral blood cells was elevated in the IS patients. Significant correlations were observed between EPCs or ECs and Big ET-1 protein or mRNA levels in HS but not in the IS patients. We suggest that ET-1 may play a role in pathophysiology of stroke and subsequent EPC mobilisation; however, further studies aimed at the precise elucidation of this issue are required.