Serum Levels of Adipolin and Adiponectin and Their Correlation with Perinatal Outcomes in Gestational Diabetes Mellitus.

Objectives: This study aimed to investigate the serum level of adipolin and adiponectin in healthy pregnant women and pregnant women with gestational diabetes mellitus (GDM) during the second trimester, the prepartum period, and in the newborns of these patients. Methods: A total of 55 women diagnosed with GDM and 110 healthy pregnant women were included in this study. Pearson's and Spearman's correlation coefficients were calculated to determine the association of adipolin and adiponectin with anthropometric markers of obesity (body mass index (BMI), mid-upper arm circumference (MUAC), tricipital skinfold thickness (TST)), inflammation markers (neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), C-reactive protein (CRP)), and maternal glucose homeostasis parameters (fasting glucose, insulin, C peptide, glycosylated hemoglobin A1c (HbA1c), Insulin Resistance-Homeostatic Model Assessment (IR HOMA)). Results: There were no statistical differences between the adipolin value in patients with GDM compared to healthy patients (p = 0.65 at diagnosis and p = 0.50 prepartum) and in newborns from mothers with GDM compared to healthy mothers (p = 0.24). Adipolin levels are significantly higher in patients with GDM who gave birth via cesarean section (p = 0.01). In patients with GDM, the adipolin level correlates positively with HgA1c in the prepartum period. We found a positive correlation between the maternal adipolin values at diagnosis and prepartum and neonatal adipolin (respectively: r = 0.556, p = 0.001; r = 0.332, p = 0.013). Adiponectin levels were significantly lower in patients with GDM at diagnosis and prepartum (p = 0.0009 and p = 0.02), but their levels increased prepartum (5267 ± 2114 ng/mL vs. 6312 ± 3150 ng/mL p = 0.0006). Newborns of mothers with GDM had lower adiponectin levels than newborns of healthy mothers (p < 0.0001). The maternal adiponectin value correlates negatively with maternal BMI, MUAC, and IR HOMA in both groups at diagnosis and prepartum. There were no differences between the groups in terms of cesarean rate (p > 0.99). The relative risk of occurrence of adverse events in patients with GDM compared to healthy ones was 2.15 (95% CI 1.416 to 3.182), and the odds ratio for macrosomia was 4.66 (95% CI 1.591 to 12.69). Conclusions: There was no difference in adipolin levels between mothers with GDM and healthy mothers during the second trimester and the prepartum period. Adipolin is known to enhance insulin sensitivity and reduce inflammation, but unlike adiponectin, it does not appear to contribute to the development of GDM.

Optimally Controlled Diabetes and Its Influence on Neonatal Outcomes at a Level II Center: A Study on Infants Born to Diabetic Mothers.

Background and Objectives: We investigated the effect of optimal maternal glycemic control on neonatal outcomes among infants born to mothers with diabetes. Materials and Methods: In this prospective study, we assessed 88 eligible mothers admitted to the obstetrics department for pregnancy evaluation. Our analysis included 46 infants born to diabetic mothers (IDMs) and 138 infants born to unaffected mothers, all admitted to the Level II Neonatal Intensive Care Unit (NICU). Results: Mothers affected by diabetes were generally older and exhibited a higher body mass index (BMI) and a greater number of gestations, although parity did not differ significantly. Cesarean section emerged as the most frequently chosen mode of delivery. A significantly higher proportion of infants in the affected group presented with respiratory disease (3% vs. 19.5%), which required NICU admission (4.3% vs. 23.9%), phototherapy (18.1% vs. 43.5%), and had congenital heart defects or myocardial hypertrophy (15.2% and 26% vs. 3% and 4.3%) compared to matched controls (p < 0.05). Conclusions: This study underscores the persistence of adverse neonatal outcomes in IDMs, even when maternal glycemic control is optimized. It calls for further investigation into potential interventions and strategies aimed at enhancing neonatal outcomes in this population.

Normative echocardiography data of myocardial adaptation to extrauterine life: a review of prospective studies.

Recent research has increased focus and interest in characterizing the physiology of the transition circulation using echocardiography. Critique of published normative neonatal echocardiography data among healthy term neonates has not been performed. We have performed a comprehensive literature review using the key terms: cardiac adaptation, hemodynamics, neonatal transition, term newborns. Studies were included if they had reported echocardiography indices of cardiovascular function in the presence of maternal diabetes, intrauterine growth restricted newborns and prematurity and had a comparison group of healthy term newborns within first seven postnatal days. Sixteen published studies evaluating transitional circulation in healthy newborns were included. There was marked heterogeneity in the methodologies used; specifically, inconsistency in time of evaluation and imaging techniques used makes it challenging to determine specific trends of expected physiologic changes. Some studies revealed nomograms for echocardiography indices, though limitations persist in terms of sample size, number of reported parameters and consistency of measurement technique. A comprehensive standardized echocardiography framework which includes consistent techniques for assessment dimensions, function, blood flow, pulmonary/systemic vascular resistance, and shunts pattern is warranted to ensure consistency in the use of echocardiography to guide care of healthy and sick newborns.

Prevalence and Risk Factors of Depression and Anxiety among Women in the Last Trimester of Pregnancy: A Cross-Sectional Study.

Pregnancy represents a psychologically and emotionally vulnerable period, and research indicates that pregnant women have a higher prevalence of symptoms of anxiety and depression, debunking the myth that hormonal changes associated with pregnancy protect the mother. In recent years, several researchers have focused on the study of prenatal anxiety/depression-emotional disorders manifested by mood lability and low interest in activities-with a high prevalence. The main objective of this research was to conduct an antenatal screening in a cohort of pregnant women hospitalized for delivery in order to assess the prevalence of anxiety and depression. The secondary objective was to identify the risk factors associated with depression and anxiety in women in the third trimester of pregnancy. We carried out a prospective study in which we evaluated 215 pregnant women in the third trimester of pregnancy hospitalized for childbirth at the Obstetrics and Gynecology Clinic of the Târgu-Mureș County Clinical Hospital. The research was carried out between December 2019 and December 2021. The results showed that age and the environment of origin are the strongest predictors of mental health during pregnancy (OR = 0.904, 95%CI: 0.826-0.991; p = 0.029). For women from urban areas, there is an increased probability of falling at a higher level on the dependent variable (moderate depression) (OR = 2.454, 95%CI: 1.086-5.545; p = 0.032). In terms of health behaviors, none of the variables were statistically significant predictors of the outcome variable. The study highlights the importance of monitoring mental health during pregnancy and identifying relevant risk factors to provide appropriate care to pregnant women and the need for interventions to support the mental health of pregnant women. Especially in Romania, where there is no antenatal or postnatal screening for depression or other mental health conditions, these results could be used to encourage the implementation of such screening programs and appropriate interventions.

The Relationship between Psychological Suffering, Value of Maternal Cortisol during Third Trimester of Pregnancy and Breastfeeding Initiation.

Background and Objectives: Cortisol, the stress hormone, is an important factor in initiating and maintaining lactation. Maternal suffering during pregnancy is predictive for the initiation and shorter duration of breastfeeding and can also lead to its termination. The aim of this study is to evaluate the relationship between the level of salivary cortisol in the third trimester of pregnancy and the initiation of breastfeeding in the postpartum period in a cohort of young pregnant women who wanted to exclusively breastfeed their newborns during hospitalization. Materials and Methods: For the study, full-term pregnant women were recruited between January and May 2022 in the Obstetrics and Gynecology Clinic of the Mureș County Clinical Hospital. Socio-demographic, clinical obstetric and neonatal variables were collected. Breastfeeding efficiency was assessed using the LATCH Breastfeeding Assessment Tool at 24 and 48 h after birth. The mean value of the LATCH score assessed at 24 and 48 h of age was higher among mothers who had a higher mean value of salivary cortisol measured in the third trimester of pregnancy (p < 0.05). A multivariate logistic regression model was used to detect risk factors for the success of early breastfeeding initiation. Results: A quarter of pregnant women had a salivary cortisol level above normal limits during the third trimester of pregnancy. There is a statistically significant association between maternal smoking, alcohol consumption during pregnancy and the level of anxiety or depression. Conclusions: The most important finding of this study was that increased salivary cortisol in the last trimester of pregnancy was not associated with delayed initiation/absence of breastfeeding.

Early Surfactant Therapy for Respiratory Distress Syndrome in Very Preterm Infants.

BACKGROUND: It is currently considered that early initiation of nasal continuous positive airway pressure, using a less invasive exogenous surfactant administration and avoiding mechanical ventilation as much as possible to minimize lung damage, may reduce mortality and/or the risk of morbidities in preterm infants. The aim of our study was to quantify our experience and compare different strategies of surfactant administration, to investigate which method is associated with less morbidity. MATERIALS AND METHODS: A total of 135 preterm infants with early rescue surfactant administration for respiratory distress syndrome were included in the study. The infants were treated in an academic, Level III Neonatal Intensive Care Unit over a 3-year period between 1 December 2018 and 1 December 2021. Patients were separated into three groups: those with standard surfactant administration; those with Less Invasive Surfactant Administration-LISA; and those with Intubation Surfactant Administration Extubation-INSURE. As a primary outcome, we followed the need for intubation and mechanical ventilation within 72 h, while the secondary outcomes were major neonatal morbidities and death before discharge. RESULTS: The surfactant administration method was significantly associated with the need for mechanical ventilation within 72 h after the procedure (p < 0.001). LISA group infants needed less MV (OR = 0.538, p = 0.019) than INSURE group infants. We found less morbidities (OR = 0.492, p = 0.015) and deaths before discharge (OR = 0.640, p = 0.035) in the LISA group compared with the INSURE group. The analysis of morbidities found in infants who were given the surfactant by the LISA method compared with the INSURE method showed lower incidence of pneumothorax (3.9% vs. 8.8%), intraventricular hemorrhage (17.3% vs. 23.5%), intraventricular hemorrhage grade 3 and 4 (3.9% vs. 5.9%), sepsis/probable sepsis (11.5% vs. 17.7%) retinopathy of prematurity (16.7% vs. 26.7%) and deaths (3.9% vs. 5.9%). There were no significant differences between groups in frequencies of bronchopulmonary dysplasia, necrotizing enterocolitis and patent ductus arteriosus. CONCLUSIONS: Less invasive surfactant administration methods seem to have advantages regarding early need for mechanical ventilation, decreasing morbidities and death rate. In our opinion, the LISA procedure may be a good choice in spontaneously breathing infants regardless of gestational age.

Changes Overtime in Perinatal Management and Outcomes of Extremely Preterm Infants in One Tertiary Care Romanian Center.

Background and Objectives: Extremely preterm infants were at increased risk of mortality and morbidity. The purpose of this study was to: (1) examine changes over time in perinatal management, mortality, and major neonatal morbidities among infants born at 250-286 weeks' gestational age and cared for at one Romanian tertiary care unit and (2) compare the differences with available international data. Material and Methods: This study consisted of infants born at 250-286 weeks in one tertiary neonatal academic center in Romania during two 4-year periods (2007-2010 and 2015-2018). Major morbidities were defined as any of the following: severe intraventricular hemorrhage (IVH), severe retinopathy of prematurity (ROP), necrotizing enterocolitis (NEC), and bronchopulmonary dysplasia (BPD). Adjusted logistic regression models examined the association between the mortality and morbidity outcome and the study period. Results: The two cohorts differed with respect to antenatal antibiotics and rates of cesarean birth but had similar exposure to antenatal steroids and newborn referral to the tertiary care center. In logistic regression analyses, infants in the newer compared to the older cohort had a lower incidence of death (OR: 0.19; 95% CI: 0.11-0.35), a lower incidence of IVH (OR: 0.26; 95% CI: 0.15-0.46), and increased incidence of NEC (OR: 19.37; 95% CI: 2.41-155.11). Conclusions: Changes over time included higher use of antenatal antibiotics and cesarean delivery and no change in antenatal steroids administration. Overall mortality was lower in the newer cohort, especially for infants 250-266 weeks' gestation, NEC was higher while BPD and ROP were not different.

Psychological Stress Perceived by Pregnant Women in the Last Trimester of Pregnancy.

Pregnancy is characterized by changes in neuroendocrine, cardiovascular, and immune function. For this reason, pregnancy itself is perceived as a psychological "stress test". Research to date has focused on stress exposure. The aim of the study was to evaluate the influence of associated factors on the level of stress experienced by pregnant patients. We conducted a prospective study that included 215 pregnant women in the third trimester of pregnancy, hospitalized in the Obstetrics and Gynecology Clinic II in Târgu-Mureș, between December 2019 and December 2021, who were evaluated by the ABS II scale. All patients included in the study filled in a questionnaire that included 76 questions/items, in which all the data necessary for the study were recorded. The results obtained from the study showed that pregnant women in urban areas (53.49%) are more vulnerable than those in rural areas (46.51%), being influenced by social and professional stressors, social determinants playing a critical role in pregnancy and in the newborn. Patients who have had an imminent abortion in their current pregnancy have a significantly higher score of irrationality than those with normal pregnancy, which shows that their emotional state can negatively influence the phenomenon of irrationality. There is a statistically significant association between pregnancy type I (normal pregnancy or imminent pregnancy) and irrationality class (p = 0.0001; RR: 2.150, CI (95%): 1.154−4.007). In the case of women with desired pregnancies, the risk of developing irrationality class IV−V is 4.739 times higher, with the association being statistically significant (p < 0.0001; RR 4.739; CI (95%): 2.144−10.476). The analysis of the obtained results demonstrates the importance of contributing factors and identifies the possibility of stress disorders, occurring in the last trimester of pregnancy, disorders that can have direct effects on maternal and fetal health. We consider it extremely important to carry out evaluations throughout the pregnancy. At the same time, it is necessary to introduce a screening program to provide psychological counseling in the prenatal care of expectant mothers.

Comparative evaluation of echocardiography indices during the transition to extrauterine life between small and appropriate for gestational age infants.

Objectives: To study changes in heart function and hemodynamics during the transitional period in small for gestational (SGA) infants and appropriate (AGA) healthier counterparts. Design: A hospital based prospective observational study was performed at a perinatal center. Echocardiograms were performed on the first postnatal day and again at 48 h age. Term SGA infants were compared with those AGA newborns matched for the GA and mode of delivery. Results: Eighteen SGA infants were compared with 18 AGA infants [gestation 38 ± 1.5 vs. 38 ± 1.2 weeks, p > 0.05 and birthweight 2331 ± 345 vs. 3332 ± 405 grams, p < 0.05, respectively]. Maternal weight and body mass index was higher among non-affected pregnancies, 61% infants were born vaginally, and no differences in cord blood pH at birth were noted. SGA infants had higher systolic and mean blood pressure at both time points, lower indices of right ventricular (RV) performance [TAPSE (tricuspid annular peak systolic excursion) 7.4 ± 2.8 vs. 9.3 ± 0.7 on day 1, 7.2 ± 2.8 vs. 9.2 ± 0.5 on day 2, p = 0.001], lower pulmonary acceleration time (PAAT) suggestive of elevated pulmonary vascular resistance [56.4 ± 10.5 vs. 65.7 ± 13.2 on day 1, 61.4 ± 12.5 vs. 71.5 ± 15.7 on day 2, p = 0.01] and higher left ventricular (LV) ejection fraction [62.1 ± 7.8 vs. 54.9 ± 5.5 on day 1, 61.9 ± 7.6 vs. 55.8 ± 4.9 on day 2, p = 0.003]. Conclusions: SGA infants had evidence of higher pulmonary vascular resistance, and lower RV performance during the postnatal transition. The relevance and impact of these changes to hemodynamic disease states during the postnatal transition requires prospective investigation.

Trends in outcomes of very preterm infants in Romania: A tale of three cities.

BACKGROUND: Although survival of preterm infants has improved, prematurity remains the second most frequent cause of death before 5 years of age in Romania. Data on the changing mortality of Romanian preterm infants born before 29 weeks of gestation have not been available. METHODS: Outcomes of infants of gestational age 25-28 weeks born in 2007-2010 (n = 247) were compared with those born in 2011-2014 (n = 235). Data were analyzed from three tertiary neonatal intensive care centers. Mortality rates and major morbidities were compared between these two epochs. RESULTS: Infants in the later epoch were more likely to have been born by cesarean section and had higher 1 and 5 min Apgar scores. Mortality rate decreased significantly with increasing gestational age at birth. Between the two epochs, the in-hospital mortality rate decreased from 65.6% to 29.4% (P < 0.001); death in the first 48 h decreased from 30.0% to 8.5% (P < 0.001); and prevalence of severe intraventricular hemorrhage decreased from 52.2% to 11.9% (P < 0.001). There were significant increases in the rates of necrotizing enterocolitis and bronchopulmonary dysplasia among survivors but no change in the rate of retinopathy of prematurity. The rate of antenatal corticosteroid use did not change and was only 47% in the more recent epoch (2011-2014). CONCLUSIONS: Overall mortality is decreasing, and infants admitted in the later epoch had substantially different rates of mortality and several serious morbidities. The low rate of antenatal corticosteroid use provides an opportunity for further reductions in mortality and morbidity among very preterm infants born in Romania.

Teenage Pregnancies: Risk Factors and Associated Neonatal Outcomes in an Eastern-European Academic Perinatal Care Center.

OBJECTIVES: This study aims to compare women with early (13-16 years), late teenage (17-19 years), and adult (25-29 years) pregnancies regarding pregnancy risk factors and reproductive outcomes. METHODS: An observational study, utilizing medical charts and direct interview, conducted in an academic hospital during January 2011 and December 2012. Our sample comprised 395 teenage and 736 adult pregnancies. RESULTS: Pregnant teenagers were more likely than adults to be single (41.7 vs. 33.2%; odds ratio [OR]: 1.43, 95% confidence interval [CI]: 1.11-1.84), to live in a rural area (70.9 vs. 53.9%; OR: 2.07, 95% CI: 1.60-2.69), and to live with extended family (74.2 vs. 16.0%; OR: 15.04, 95% CI: 11.15-20.29). Adolescent mothers were more likely than adult mothers to give birth by vaginal delivery (78.5 vs. 69.6%; OR: 1.82, 95% CI: 1.17-2.84), and rate of operative delivery was lower amongst this group (8.6 vs. 9.8%; OR: 0.8, 95% CI: 0.5-1.3). The newborns of adolescent mothers were more likely to be low birth weight (14.9 vs. 9.1%; OR: 1.75, 95% CI: 1.20-2.54) and more likely to successfully breastfeed (91.9 vs. 82.2%; OR: 2.45; 95% CI: 1.63-3.69) but the length of hospital stay was similar with adult mothers' newborns. CONCLUSIONS: The distinct risk factors and behaviors associated with pregnancy, among teenagers may help address the health needs of this unique and vulnerable group and their offspring.

Congenital Heart Disease Requiring Maintenance of Ductus Arteriosus in Critically Ill Newborns Admitted at a Tertiary Neonatal Intensive Care Unit.

INTRODUCTION: Congenital heart diseases (CHD) have been reported to be responsible for 30 to 50% of infant mortality caused by congenital disabilities. In critical cases, survival of newborns with CHD depends on the patency of the ductus arteriosus (PDA), for maintaining the systemic or pulmonary circulation. The aim of the study was to assess the efficacy and side effects of PGE (prostaglandin E) administration in newborns with critical congenital heart disease requiring maintenance of the ductus arteriosus. MATERIAL AND METHOD: All clinical and paraclinical data of 66 infants admitted to one referral tertiary level academic center and treated with Alprostadil were analyzed. Patients were divided into three groups: Group 1: PDA dependent pulmonary circulation (n=11) Group 2: PDA dependent systemic circulation (n=31) Group 3: PDA depending mixed circulation (n=24). RESULTS: The mean age of starting PGE1 treatment was 2.06 days, 1.91 (+/-1.44) days for PDA depending pulmonary flow, 2.39 (+/-1.62) days for PDA depending systemic flow and 1.71 (+/1.12) for PDA depending mixing circulation. PEG1 initiation was commenced 48 hours after admission for 72%, between 48-72 hours for 6%, and after 72 to 120 hours for 21% of newborns detected with PDA dependent circulation. Before PEG1 initiation the mean initial SpO2 was 77.89 (+/- 9.2)% and mean initial oxygen pressure (PaO2) was 26.96(+/-6.45) mmHg. At the point when stable wide open PDA was achieved their mean SpO2increased to 89.73 (+/-8.4)%, and PaO2 rose to 49 (+/-7.2) mmHg. During PGE1 treatment, eleven infants (16.7%) had apnea attacks, five children (7.5%) had convulsions, 33 (50%) had fever, 47 (71.2%) had leukocytosis, 52 (78.8%) had edema, 25.8% had gastrointestinal intolerance, 45.5% had hypokalemia, and 63.6% had irritability. CONCLUSIONS: For those infants with severe cyanosis or shock caused by PDA dependent heart lesions, the initiation and maintenance of PGE1 infusion is imperative. The side effects of this beneficial therapy were transient and treatable.

Mortality and morbidity of very preterm infants in Romania: how are we doing?

BACKGROUND: Birth before 28 weeks of gestation is associated with high mortality and morbidity. The purpose of this study was to examine characteristics associated with in-hospital mortality and morbidity among extremely low-birthweight neonates admitted to three tertiary care centers in Romania. METHODS: The study was conducted in three Romanian hospitals with level-III neonatal intensive care units. We studied singleton live births at the established Romanian limit of viability (i.e., 25-28 weeks' gestational age) born between January 2007 and December 2010 (n = 227). Infants born in non-level-III facilities transferred to these three centers were included in our study (n = 39). Descriptive and multivariate statistical analyses were used to describe the population and examine outcomes and risk factors. RESULTS: During the study period, 62 neonates (27.3%) were delivered at 25 weeks, 56 (24.7%) were delivered at 26 weeks, 56 (24.7%) at 27 weeks, and 53 (23.3%) at 28 weeks. Overall in-hospital mortality was 65% (from 85% at 25 weeks to 35% at 28 weeks). The rates for major morbidities were necrotizing enterocolitis 8.8%, bronchopulmonary dysplasia 12.5%, and retinopathy of prematurity (stage higher than 2) 26.2%. CONCLUSIONS: During 2007-2010, in-hospital survival of infants admitted to three neonatal intensive care units in Romania was 35% and ranged from 14% at 25 weeks to 64% at 28 weeks.

Integrated sensor-based monitoring system for pest and disease control in greenhouses.

Diseases and pests are a problem even in greenhouse crops, problem which has to be solved without threatening the plant. Crop protection requires frequent updates in information and therefore sensor networks that are real time monitoring systems are the ones that can deliver such information. The purpose of this paper is to present a way of preventing the appearance of diseases and pests in a greenhouse by using a monitoring system composed of an integrated sensor network. Our sensor system is doing a real time monitoring of the following parameters in the greenhouse: light intensity, soil moisture and temperature, air temperature and humidity and air temperature at canopy level; all of the data being stored using a software made by "Tedelco". A real time monitoring camera is also used for pest and disease detection. A pot experiment, using beans, was established inside the greenhouse to test the applicability of the system. In order to assure the optimal conditions for the inhibition of pests, the greenhouse is also equipped with an artificial lighting system specially designed for greenhouses, an irrigation system and an artificial fog system. Sensor systems are the ideal support for preventive monitoring and at the same time it offers all the support data necessary for decision making regarding crops development.

Platelet-derived growth factor receptor-ß-positive telocytes in skeletal muscle interstitium.

Telocytes (TCs) represent a new cell type recently described in mammalian skeletal muscle interstitium as well as in other organs. These have a specific morphology and phenotype, both in situ and in vitro. Telocytes are cells with long and slender cell prolongations, in contact with other interstitial cells, nerve fibres, blood capillaries and resident stem cells in niches. Our aim was to investigate the potential contribution of TCs to micro-vascular networks by immunofluorescent labelling of specific angiogenic growth factors and receptors. We found that in human skeletal muscle TCs were constantly located around intermediate and small blood vessels and endomysial capillaries. Epi-fluorescence and laser confocal microscopy showed that TCs express c-kit, platelet-derived growth factor receptor (PDGFR)-ß and VEGF, both in situ and in vitro. Telocytes were constantly located in the perivascular or pericapillary space, as confirmed by double staining of c-kit/CD31, PDGFR-ß/CD31 and PDGFR-ß/α-smooth muscle actin, respectively. Electron microscopy (EM) differentiated between pericytes and other cell types. Laminin labelling showed that TCs are not enclosed or surrounded by a basal lamina in contrast to mural cells. In conclusion, a) PDGFR-ß could be used as a marker for TCs and b) TCs are presumably a transitional population in the complex process of mural cell recruitment during angiogenesis and vascular remodelling.

Pharmacological modulation of the Hedgehog pathway differentially affects dorsal/ventral patterning in mouse and human embryonic stem cell models of telencephalic development.

A complex set of extrinsic and intrinsic signals acts in specific temporal and spatial orders to enable neural differentiation during development. These processes have been extensively studied in animal models, but human neural development remains much less understood. This lack of detailed information about human early neurogenesis is a hindrance for the differentiation of pluripotent stem cell lines into specific neuronal phenotypes. Therefore, it is important to strengthen the interspecies comparative approaches. We describe a novel model system in which in vitro differentiation of human and mouse embryonic stem (ES) cells are temporally aligned to each other and compared with mouse telencephalic neurogenesis in vivo. In this comparative model system, we tested the in vitro role of Hedgehog (Hh) signaling for ES cell-derived telencephalic differentiation. In vivo, Hh signaling mediates dorsal/ventral patterning during early stages of telencephalic development. We monitored the effect of pharmacological modulators of the Hh signaling pathway, purmorphamine-an agonist and cyclopamine-an antagonist of the Smoothened receptor (Smo), on the expression of region-specific transcription factors and signaling molecules relevant for telencephalic development in vivo. Purmorphamine strongly upregulated the expression of telencephalic ventral markers Nkx2.1, Nkx6.2, Lhx6, and Lhx8 in mouse and human cells, thus reflecting the in vivo process of the medial ganglionic eminence patterning and specification. Cyclopamine upregulated the expression of telencephalic dorsal markers, but at lower levels in human compared with mouse cells. Modulation of Smo in vitro differentially affected, in mouse and human cells, the expression of molecules of the Hh pathway, especially the Gli1 and Gli3 effectors, Sonic Hh ligand and Ptch receptors. These results provide evidence for the different default differentiation of mouse and human ES cells and prove the utility of the comparative system for optimizing the directed differentiation of human pluripotent stem cells.

Telocytes and putative stem cells in the lungs: electron microscopy, electron tomography and laser scanning microscopy.

This study describes a novel type of interstitial (stromal) cell - telocytes (TCs) - in the human and mouse respiratory tree (terminal and respiratory bronchioles, as well as alveolar ducts). TCs have recently been described in pleura, epicardium, myocardium, endocardium, intestine, uterus, pancreas, mammary gland, etc. (see www.telocytes.com ). TCs are cells with specific prolongations called telopodes (Tp), frequently two to three per cell. Tp are very long prolongations (tens up to hundreds of µm) built of alternating thin segments known as podomers (≤ 200 nm, below the resolving power of light microscope) and dilated segments called podoms, which accommodate mitochondria, rough endoplasmic reticulum and caveolae. Tp ramify dichotomously, making a 3-dimensional network with complex homo- and heterocellular junctions. Confocal microscopy reveals that TCs are c-kit- and CD34-positive. Tp release shed vesicles or exosomes, sending macromolecular signals to neighboring cells and eventually modifying their transcriptional activity. At bronchoalveolar junctions, TCs have been observed in close association with putative stem cells (SCs) in the subepithelial stroma. SCs are recognized by their ultrastructure and Sca-1 positivity. Tp surround SCs, forming complex TC-SC niches (TC-SCNs). Electron tomography allows the identification of bridging nanostructures, which connect Tp with SCs. In conclusion, this study shows the presence of TCs in lungs and identifies a TC-SC tandem in subepithelial niches of the bronchiolar tree. In TC-SCNs, the synergy of TCs and SCs may be based on nanocontacts and shed vesicles.

Identification of telocytes in skeletal muscle interstitium: implication for muscle regeneration.

Skeletal muscle interstitium is crucial for regulation of blood flow, passage of substances from capillaries to myocytes and muscle regeneration. We show here, probably, for the first time, the presence of telocytes (TCs), a peculiar type of interstitial (stromal) cells, in rat, mouse and human skeletal muscle. TC features include (as already described in other tissues) a small cell body and very long and thin cell prolongations-telopodes (Tps) with moniliform appearance, dichotomous branching and 3D-network distribution. Transmission electron microscopy (TEM) revealed close vicinity of Tps with nerve endings, capillaries, satellite cells and myocytes, suggesting a TC role in intercellular signalling (via shed vesicles or exosomes). In situ immunolabelling showed that skeletal muscle TCs express c-kit, caveolin-1 and secrete VEGF. The same phenotypic profile was demonstrated in cell cultures. These markers and TEM data differentiate TCs from both satellite cells (e.g. TCs are Pax7 negative) and fibroblasts (which are c-kit negative). We also described non-satellite (resident) progenitor cell niche. In culture, TCs (but not satellite cells) emerge from muscle explants and form networks suggesting a key role in muscle regeneration and repair, at least after trauma.

Telocytes in pleura: two- and three-dimensional imaging by transmission electron microscopy.

Information about the ultrastructure of connective (interstitial) cells supporting the pleural mesothelium is scarce. Our aim has been to examine whether telocytes (TCs) are present in pleura, as in epicardium and mesentery. TCs are a distinct type of cell, characterized by specific prolongations named telopodes (Tp). We have used transmission electron microscopy (TEM) and electron tomography (ET) to determine whether ultrastructural diagnostic criteria accepted for TCs are fulfilled by any of the cell subpopulations existing in the sub-mesothelial layer in mouse and human pleura. TCs have been identified with TEM by their characteristic prolongations. Tp appear long and moniliform, because of the alternation of podomeres (thin segments of less than 0.2 µm) and podoms (small dilations accommodating caveolae, mitochondria, and endoplasmic reticulum). Tp ramifications follow a dichotomic pattern and establish specialized cell-to-cell junctional complexes. TCs, via their Tp, seem to form an interstitial network beneath the mesothelium, covering about two-thirds of the abluminal mesothelial layer. ET has revealed complex junctional structures and tight junctions connecting pleural TCs, and small vesicles at this level in Tp. Thus, pleural TCs share significant similarities with TCs described in other serosae. Whether TCs are a (major) player in mesothelial-cell-induced tissue repair remains to be established. Nevertheless, the extremely long thin Tp and complex junctional structures that they form and the release of vesicles (or exosomes) indicate the participation of TCs in long-distance homo- or heterocellular communication.