Concentrations Of Epidermal Growth Factor Research Articles

Comparison of salivary nitric oxide and epidermal growth factor level between diabetic patients and healthy individuals

The purpose of the current study was to compare salivary Nitric oxide and epidermal growth factor level in diabetic patients and healthy individuals. In this paired-control study 20 patients with type 1 diabetes mellitus, 20 patients with type 2 diabetes mellitus and 20 age and sex matched healthy subjects participated. The level of salivary Nitric oxide was increased in type 1 and 2 diabetic patients in comparison to control individuals (P = 0.037 and P = 0.058), respectively. Epidermal growth factor concentration was higher in type 1 and 2 diabetic patients compare to healthy ones, (P = 0.037 and P = 0.005) respectively. There was no significant difference between salivary Nitric oxide and Epidermal growth factor level regarding to the type of diabetes (P > 0.05). Significant statistical correlation was found between Nitric oxide and Epidermal growth factor levels and the fasting blood glucose and HbA1c (P < 0.001). Conclusions: Salivary Nitric oxide and Epidermal growth factor levels were higher in type 1 and type 2 diabetic patients and there was correlation with severity of disease.

PI3K-mediated glioprotective effect of epidermal growth factor under oxidative stress conditions.

To determine the effects of epidermal growth factor (EGF) on the proliferation and migration of Müller cell line Moorfields/Institute of Ophthalmology-Müller 1 (MIO-M1), and its related molecular mechanisms under normal and oxidative stress conditions. Müller cells were cultured with different concentrations of EGF in the presence or absence of varied amounts of H2O2 and glucose oxidase (GO) which induced oxidative stress. The proliferation and migration of Müller cells were examined by 5-Bromo-2-deoxyUridine (BrdU), MTT assay, Transwell assay and scratch wound healing assays. The cell viability was determined with the MTT assay. The secretion of EGF by Müller cells was evaluated by ELISA. Western blot was performed to detect the activation of extracellular regulated protein kinases (ERK)1/2 and Akt signal pathways. EGF stimulated the proliferation and migration of Müller cells in a concentration-dependent manner in vitro. Under oxidative damage condition, 2h of pretreatment with 10-100 ng/mL EGF can mostly inhibit 50% lethal dose of 0.08 mmol/L H2O2-induced cell damage. The Western blot results showed that after Müller cells were exposed to varying EGF for 24h, Akt and ERK1/2 were phosphorylated in a dose-dependent manner. In the presence of the LY294002, the potent PI3K inhibitor, the p-Akt was significantly attenuated. EGF may induce the proliferation and migration of human Müller cells through the Akt and the ERK1/2 signal pathways, and induce PI3K-mediated glioprotective effect under oxidative stress.

Effects of epidermal growth factor, platelet derived growth factor and growth hormone on cultured rat keratinocytes cells in vitro.

Some growth factors, such as Epidermal Growth Factor (EGF), Growth Hormone (GH) and Platelet Derived Growth Factor (PDGF) have beneficial effects on keratinocyte proliferation and wound healing. Although the mechanism of these factors is unclear. In response to injury, growth factors are secreted by kinds of cutaneous cells. The goal of this project is to investigate the factors that could cause proliferate of the keratinocyte cells in vitro. The keratinocytes were removed from rat pups (10 days). Cultured in media with different concentration of GH, PDGF and EGF separately. The proliferation of cells was evaluated by the method of MTT and 3H-thymidine incorporation. Proliferation of keratinocytes was significantly higher in experimental groups than in control group. EGF maximally stimulated at 10 and 25 ng mL(-1). PDGF-BB maximally stimulated at 50 ng mL(-1), respectively. And maximal stimulation of GH was 2.5 IU L(-1). GH, PDGF-BB and EGF stimulate keratinocyte cells proliferation in different concentration. These growth factors could play in healing of the skin.

Analysis of growth factors in serum and induced sputum from patients with asthma.

Epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), the AA and BB isoforms of platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF) are involved in the pathogenesis of airway inflammation in asthma. In the present study, the associations between asthmatic phenotypes and the expression levels of these mediators in induced sputum and serum were investigated. A total of 62 asthmatic patients were divided into eosinophilic or neutrophilic phenotypes by cytological classification of the induced sputum. In addition, patients were classified according to lung function (FEV1/FVC >70% or FEV1/FVC <70%) and asthma severity (mild, moderate or severe). The concentrations of EGF, bFGF, PDGF-AA, PDGF-BB and VEGF in the serum and induced sputum were measured using sandwich enzyme immunoassays. VEGF levels in the serum and induced sputum were higher in patients with an eosinophilic phenotype compared with those with a neutrophilic phenotype. In addition, VEGF expression was higher in patients with an FEV1/FVC value of <70% as compared with patients with an FEV1/FVC value of >70%. Furthermore, the levels of VEGF were higher in patients with severe asthma compared with the patients with mild and moderate asthma. There were no statistically significant differences observed with regard to EGF, bFGF, PDGF-AA and PDGF-BB levels among the various phenotypes. Therefore, the observations of the present study indicated that increased VEGF expression in the serum and induced sputum of patients may be associated with eosinophilic airway inflammation, severe airflow limitation and the severity of asthma.

Impact of epidermal growth factor single‐nucleotide polymorphism on recurrence of hepatocellular carcinoma after hepatectomy in patients with chronic hepatitis C virus infection

Epidermal growth factor (EGF) gene single-nucleotide polymorphism (SNP) is associated with an increased risk of hepatic tumors. The study aimed to elucidate the impact of EGF SNP and EGF receptor (EGFR) expression on the recurrence of hepatocellular carcinoma (HCC) after hepatectomy. To examine the impact of EGF SNP and EGFR on recurrent HCC, we retrospectively analyzed 141 HCC patients with chronic hepatitis C virus infection who underwent curative hepatectomy. The EGF *61 GG allele was present in 69 patients (48.9%), AG in 56 (39.7%) and AA in 16 (11.4%). The AA group had a significantly lower rate of intrahepatic metastasis (0% vs 16.5%, P = 0.02), lower serum EGF concentration (26.3 ± 15.9 pg/mL vs 43.4 ± 30.5 pg/mL, P = 0.02) and lower proportion of early recurrence (≤2 years; 28.6% vs 71.2%, P = 0.03) than the AG/GG group. The AA group had significantly higher recurrence-free survival than the AG/GG group (P = 0.04), but there was no significant difference in overall survival between these two groups (P = 0.97). High versus low EGFR expression analyzed by immunohistochemical staining in cancer cells was not significantly associated with overall survival (P = 0.37) or recurrence-free survival (P = 0.39). Therefore, EGF *61 AA was associated with a lower risk of recurrence after curative hepatectomy for HCC in patients with hepatitis C virus infection than other genotypes, but EGFR expression in cancer cells was not significantly associated with prognosis.

Effect of psoriasis activity on epidermal growth factor (EGF) and the concentration of soluble EGF receptor in serum and plaque scales.

Epidermal growth factor receptors (EGFRs) are overexpressed in psoriatic keratinocytes, and regulate cell growth, proliferation and differentiation through binding to epidermal growth factor (EGF). The role of EGF and EGFRs in the pathogenesis of psoriasis and the contribution of their measurement to psoriasis management are still unknown. To evaluate serum concentrations of EGF, soluble (s)EGFRs and EGF content in psoriatic scales of patients with severe psoriasis, and to analyse their association with the clinical activity of the disease. Serum samples and plaque scales were collected from 51 patients with plaque-type psoriasis. Concentrations of EGF and sEGFR in serum and of EGF in scales were measured using enzyme immunoassay. Data were analysed with respect to baseline Psoriasis Area and Severity Index (PASI). Mean serum EGF concentration in patients was higher than in controls (701±72 vs. 586±63pg/mL), but the difference was not significant. Mean serum concentration of sEGFR was significantly lower than controls (40.8±1.4 vs. 86.4±11.3ng/mL, P<0.001). Serum levels of EGF showed a significant positive correlation and EGFR showed a significant negative correlation with PASI (P<0.05). No correlation was seen between PASI and EGF content in scales or between EGF and sEGFR levels. Serum EGF concentrations reached the highest mean level (914±138pg/mL) in patients with PASI>20, and this was significantly higher than the mean of 414±82pg/mL in the group with PASI<10. Mean sEGFR serum concentrations remained significantly lower than those of controls, irrespective of disease severity. Compared with controls, patients with psoriasis had increased EGF and decreased sEGFR levels in serum. EGF and sEGFR levels correlated with disease severity.

Production and reception of the growth factor in the placenta during the physiological pregnancy and the pregnancy, complicated with gestosis

30 women with physiological pregnancy and 28 women with gestosis were examined. In the early chorion obtained after abortion and on the full-term placenta the content of the epidermal growth factor (EGF), vascular-endothelial growth factor (VEGF) and their receptors were studied by means of the ELISA method. In the process of normal gestation the increase of the placental production both of the EGF and VEGF was found. During the pregnancy complicated with gestosis and miscarriage in the first trimester the content of EGF and its receptor was lower compared to the physiological values. For VEGF and its receptor opposite changes were found: the increase of quantity of the growth factor and the decrease of its receptor. In the case of gestosis and term pregnancy the content of the both growth factors and their receptors was lower than in controls. The revealed changes in production of the angiogenic growth factors and their receptors in the placenta may have the pathogenic importance in the development of gestosis.

Derivation of Myogenic Progenitors Directly From Human Pluripotent Stem Cells Using a Sphere-Based Culture

Using stem cells to replace degenerating muscle cells and restore lost skeletal muscle function is an attractive therapeutic strategy for treating neuromuscular diseases. Myogenic progenitors are a valuable cell type for cell-based therapy and also provide a platform for studying normal muscle development and disease mechanisms in vitro. Human pluripotent stem cells represent a valuable source of tissue for generating myogenic progenitors. Here, we present a novel protocol for deriving myogenic progenitors from human embryonic stem (hES) and induced pluripotent stem (iPS) cells using free-floating spherical culture (EZ spheres) in a defined culture medium. hES cell colonies and human iPS cell colonies were expanded in medium supplemented with high concentrations (100 ng/ml) of fibroblast growth factor-2 (FGF-2) and epidermal growth factor in which they formed EZ spheres and were passaged using a mechanical chopping method. We found myogenic progenitors in the spheres after 6 weeks of culture and multinucleated myotubes following sphere dissociation and 2 weeks of terminal differentiation. A high concentration of FGF-2 plays a critical role for myogenic differentiation and is necessary for generating myogenic progenitors from pluripotent cells cultured as EZ spheres. Importantly, EZ sphere culture produced myogenic progenitors from human iPS cells generated from both healthy donors and patients with neuromuscular disorders (including Becker's muscular dystrophy, spinal muscular atrophy, and familial amyotrophic lateral sclerosis). Taken together, this study demonstrates a simple method for generating myogenic cells from pluripotent sources under defined conditions for potential use in disease modeling or cell-based therapies targeting skeletal muscle.

Additive Benefits of Chondroitin Sulfate and Oriented Tethered Epidermal Growth Factor for Vascular Smooth Muscle Cell Survival

An anti-apoptotic coating combining chondroitin sulfate (CS) and coiled-coil-based tethering of epidermal growth factor (EGF) is designed for vascular applications. The oriented tethering strategy enables to reach higher EGF surface densities compared to the commonly used random covalent grafting, while using much lower concentrations of EGF during incubation. It also significantly improves vascular smooth muscle cell (VSMC) survival and resistance to apoptosis in serum-free conditions. The comparison of CS and low-fouling carboxymethylated dextran as a sublayer for growth factors highlights the tremendous benefit of CS thanks to its selective protein resistance and good cell adhesion properties. This approach can be tuned by capturing other growth factors on CS through coiled-coil interactions.

Optimal Isolation and Xeno-Free Culture Conditions for Limbal Stem Cell Function

To preserve limbal stem cell (LSC) function in vitro with xenobiotic-free culture conditions. Limbal epithelial cells were isolated from 139 donors using 15 variations of three dissociation solutions. All culture conditions were compared to the baseline condition of murine 3T3-J3 feeders with xenobiotic (Xeno) keratinocyte growth medium at 20% O2. Five Xeno and Xeno-free media with increasing concentrations of calcium and epidermal growth factor (EGF) were evaluated at 5%, 14%, and 20% O2. Human MRC-5, dermal (fetal, neonatal, or adult), and limbal stromal fibroblasts were compared. Statistical analysis was performed on the number of maximum serial weekly passages, percentage of aborted colonies, colony-forming efficiency (CFE), p63α(bright) cells, and RT-PCR ratio of p63α/K12. Immunocytochemistry and RT-PCR for p63α, ABCG2, Bmi1, C/EBPδ , K12, and MUC1 were performed to evaluate phenotype. Dispase/TrypLE was the isolation method that consistently showed the best yield, viability, and CFE. On 3T3-J2 feeders, Xeno-free medium with calcium 0.1 mM and EGF 10 ng/mL at 20% O2 supported more passages with equivalent percentage of aborted colonies, p63α(bright) cells, and p63α/K12 RT-PCR ratio compared to baseline Xeno-media. With this Xeno-free medium, MRC-5 feeders showed the best performance, followed by fetal, neonatal, adult HDF, and limbal fibroblasts. MRC-5 feeders supported serial passages with sustained high expression of progenitor cell markers at levels as robust as the baseline condition without significant difference between 20% and 5% O2. The LSC function can be maintained in vitro under appropriate Xeno-free conditions.

118 EFFECTS OF EPIDERMAL GROWTH FACTOR ON IN VITRO SURVIVAL AND ANTRUM FORMATION OF ISOLATED OVINE PREANTRAL FOLLICLES

The aim of this study was to verify the beneficial effects of different concentrations of epidermal growth factor (EGF) on survival and antrum formation of isolated ovine preantral follicles cultured in vitro. Ovine ovaries (n = 50) were collected from a local slaughterhouse and secondary follicles (150–200 μm in diameter), without antral cavities, were mechanically isolated by microdissection using 26-gauge needles. After selection, the follicles were individually cultured in 100-μL droplets of culture medium at 39°C and 5% CO2 in air for 18 days. The basic control medium consisted of α-minimal essential medium (α-MEM) supplemented with BSA; insulin, transferring and selenium; glutamine; hypoxanthine; and ascorbic acid and then referred to as α-MEM+. For the experimental conditions, follicles were cultured in α-MEM+ alone (control) or in different concentrations of EGF (1, 10, or 50 ng mL–1). Every other day, 60 μL of the culture media was replaced with fresh media. The morphological aspects of all ovine follicles were assessed every 6 days using a precalibrated ocular micrometer in a stereomicroscope at 100× magnification. Only those follicles showing an intact basement membrane, with bright and homogeneous granulosa cells and an absence of morphological signs of degeneration, were classified as morphologically normal follicles. The rupture of the basement membrane was also observed and characterised as follicle extrusion. In addition, antral cavity formation was defined as the emergence of a visible translucent cavity within the granulosa cell layers. Data from morphologically normal follicles, extruded follicles, and antrum formation rate during in vitro culture were expressed as percentages and compared by the chi-squared test, and differences were considered significant when P &lt; 0.05. The results showed that the percentage of morphologically normal follicles decreased significantly throughout the culture periods in all the treatments, except in the 50 ng mL–1 EGF group, which maintained the percentage of normal follicles from Day 0 to 6. Considering the same culture period, 50 ng mL–1 EGF treatment significantly increased the percentage of morphologically normal follicles at Day 18 compared with the control group. Moreover, the addition of EGF to the culture medium, at 50 ng mL–1, significantly reduced the precocious extrusion of oocytes and increased the percentage of antrum formation compared with the control and 1 ng mL–1 EGF after 18 days of culture. Notably, there were no significant differences between 10 ng mL–1 EGF, control medium, and 1 ng mL–1 EGF treatments. In conclusion, this study demonstrated that the addition of EGF to the in vitro culture medium, at 50 ng mL–1, increased the proportion of morphologically normal follicles and antrum formation rate of isolated ovine preantral follicles. This work was supported by FACEPE (Process APQ-0705–5.05/10). L. P. Santos is a recipient of a grant from FACEPE (Brazil).

Microfluidic Generated EGF-Gradients Induce Chemokinesis of Transplantable Retinal Progenitor Cells via the JAK/STAT and PI3Kinase Signaling Pathways

A growing number of studies are evaluating retinal progenitor cell (RPC) transplantation as an approach to repair retinal degeneration and restore visual function. To advance cell-replacement strategies for a practical retinal therapy, it is important to define the molecular and biochemical mechanisms guiding RPC motility. We have analyzed RPC expression of the epidermal growth factor receptor (EGFR) and evaluated whether exposure to epidermal growth factor (EGF) can coordinate motogenic activity in vitro. Using Boyden chamber analysis as an initial high-throughput screen, we determined that RPC motility was optimally stimulated by EGF concentrations in the range of 20-400ng/ml, with decreased stimulation at higher concentrations, suggesting concentration-dependence of EGF-induced motility. Using bioinformatics analysis of the EGF ligand in a retina-specific gene network pathway, we predicted a chemotactic function for EGF involving the MAPK and JAK-STAT intracellular signaling pathways. Based on targeted inhibition studies, we show that ligand binding, phosphorylation of EGFR and activation of the intracellular STAT3 and PI3kinase signaling pathways are necessary to drive RPC motility. Using engineered microfluidic devices to generate quantifiable steady-state gradients of EGF coupled with live-cell tracking, we analyzed the dynamics of individual RPC motility. Microfluidic analysis, including center of mass and maximum accumulated distance, revealed that EGF induced motility is chemokinetic with optimal activity observed in response to low concentration gradients. Our combined results show that EGFR expressing RPCs exhibit enhanced chemokinetic motility in the presence of low nanomole levels of EGF. These findings may serve to inform further studies evaluating the extent to which EGFR activity, in response to endogenous ligand, drives motility and migration of RPCs in retinal transplantation paradigms.

EGF RECEPTOR DYNAMICS IN EGF-RESPONDING CELLS REVEALED BY FUNCTIONAL IMAGING DURING SINGLE PARTICLE TRACKING

The epidermal growth factor (EGF) receptor transduces the extracellular EGF signal into the cells. The distribution of these EGF receptors in the plasma membrane is heterogeneous and dynamic, which is proposed to be important for the regulation of cell signaling. The response of the cells to a physiological concentration of EGF is not homogeneous, which makes it difficult to analyze the dynamics related to the response. Here we developed a system to perform functional imaging during single particle tracking (SPT) analysis. This system made it possible to observe the cytosolic Ca2+concentration to monitor the cell response while tracking individual EGF molecules and found that about half of the cells responded to the stimulation with 1.6 nM EGF. In the responding cells, the EGF receptor showed 3 modes of movement: fast (the diffusion coefficient of 0.081 ± 0.009 μm2/sec, 29 ± 9%), slow (0.020 ± 0.005 μm2/sec, 22 ± 6%), and stationary (49 ± 13%). The diffusion coefficient of the fast mode movement in the responding cells was significantly larger than that in the nonresponding cells (0.069 ± 0.009 μm2/sec, p &lt; 0.05). The diffusion coefficient of the fast mode movement is thought to reflect the monomer–dimer equilibrium of the EGF receptor. We assumed that the feedback regulation via the Ca2+signaling pathway slightly shifts the equilibrium from dimer to monomer in the responding cells.[Formula: see text]Special Issue Comment: This research paper is about the diffusion of EGF receptors in the membrane. It is therefore related with various projects in this Special Issue: the reviews about FRET41and enzymes,42and the projects about solving single molecules trajectories.43

Establishment of a holistic and scientific protocol for the authentication and quality assurance of edible bird’s nest

Edible bird’s nest (EBN) is a prestigious and superior functional food. It is expensive due to its limited supply and enormous demand. Consequently, many fake products are available in the market. This report aims to design a holistic and scientific testing method for the authentication and quality assurance of EBN. The analytical system involves a concerted approach by applying the gas chromatography–mass spectrometry (GC–MS) fingerprint of oligosaccharides, the environmental scanning electron microscopy (ESEM) of microstructure, and the immunoblotting of epidermal growth factor (EGF) in EBN. The results confirmed that genuine EBN had the presence of five monoses and EGF, whereas the counterfeit EBN did not. Moreover, the content of N-Acetylneuraminic acid (NANA) and EGF are established as unique indicators for the grades of EBN. A unique three-dimensional, crater-like microstructure was also observed in authentic EBN, but not in fake products. It is concluded that the holistic approach, including chemical, physical and biochemical studies of EBN, is a reliable and scientific method for the verification of EBN.

Correlation between salivary epidermal growth factor levels and refractory intraoral manifestations in patients with Sjögren's syndrome

Objective. To assess changes in salivary epidermal growth factor (EGF) levels and the correlation between these levels and the severity of intraoral manifestations in Sjögren's syndrome (SS).Methods. Forty SS patients and 23 controls were enrolled. Salivary EGF concentration was measured using an enzyme-linked immunosorbent assay, and intraoral manifestations were evaluated using a short version of the Oral Health Impact Profile (OHIP-14). The associations among salivary flow rate, EGF levels and the severity of intraoral manifestations were analyzed.Results. The total salivary EGF output was significantly decreased in the SS patients compared with the controls (9237.6 ± 8447.0 vs. 13296.9 ± 7907.1 pg/10 min, respectively, p = 0.033). In the SS patients, total EGF output and salivary flow rate showed a strong positive correlation (rs = 0.824, p = 0.0005), while total EGF output and disease duration showed a negative correlation (rs = −0.484, p = 0.008). Further, total EGF output was significantly correlated with the OHIP-14 score (rs = −0.721, p = 0.012).Conclusions. The salivary flow rate and EGF levels are decreased in SS, and this deterioration in saliva quality causes refractory intraoral manifestations. Our findings have provided new therapeutic targets for SS.

Functional and Histologic Changes in the Lacrimal Gland After Botulinum Toxin Injection

The purpose of this study was to evaluate changes in tear volume, epidermal growth factor (EGF), and histology of the rabbit lacrimal gland after intraglandular application of botulinum toxin. Ten New Zealand rabbits were separated into 3 groups. Eight rabbits received botulinum toxin injection (2.5 U per 0.1 mL) into the right lacrimal gland and saline injection (0.1 mL) into the left lacrimal gland as a sham control. Two rabbits were untreated to serve as normal controls. Tear volume was measured using cotton thread every 2 weeks, and 4 rabbits were killed after 2 and 4 weeks. The lacrimal glands were surgically excised and sectioned or lysed for gene expression analysis. Epidermal growth factor expression and concentration were evaluated by real-time polymerase chain reaction and enzyme-linked immunosorbent assay; morphometric and histologic analyses were performed. The rabbits that were killed 2 weeks after the injection showed decreased tear volume and increased EGF expression and concentration, but differences were not statistically significant. The rabbits that were killed 4 weeks after the injection exhibited similar results. When all 8 rabbits were considered, we detected a significant decrease in tear volume and increased EGF expression and concentration (P = 0.012, P = 0.011, and P = 0.012, respectively). The EGF level was not significantly correlated with the tear volume. There were no prominent histologic changes between the glands, and the lumen versus fibrosis ratio in the interlobular ducts showed no statistically significant difference. The use of botulinum toxin in patients with epiphora is effective, safe, and repeatable because it reduces tear volume and increases the EGF level to prevent corneal damage while causing no histologic changes.

Myocardial Mineralocorticoid Receptor Activation by Stretching and Its Functional Consequences

Myocardial stretch triggers an angiotensin II-dependent autocrine/paracrine loop of intracellular signals, leading to reactive oxygen species-mediated activation of redox-sensitive kinases. Based on pharmacological strategies, we previously proposed that mineralocorticoid receptor (MR) is necessary for this stretch-triggered mechanism. Now, we aimed to test the role of MR after stretch by using a molecular approach to avoid secondary effects of pharmacological MR blockers. Small hairpin interference RNA capable of specifically knocking down the MR was incorporated into a lentiviral vector (l-shMR) and injected into the left ventricular wall of Wistar rats. The same vector but expressing a nonsilencing sequence (scramble) was used as control. Lentivirus propagation through the left ventricle was evidenced by confocal microscopy. Myocardial MR expression, stretch-triggered activation of redox-sensitive kinases (ERK1/2-p90(RSK)), the consequent Na(+)/H(+) exchanger-mediated changes in pHi (HEPES-buffer), and its mechanical counterpart, the slow force response, were evaluated. Furthermore, reactive oxygen species production in response to a low concentration of angiotensin II (1.0 nmol/L) or an equipotent concentration of epidermal growth factor (0.1 μg/mL) was compared in myocardial tissue slices from both groups. Compared with scramble, animals transduced with l-shMR showed (1) reduced cardiac MR expression, (2) cancellation of angiotensin II-induced reactive oxygen species production but preservation of epidermal growth factor-induced reactive oxygen species production, (3) cancellation of stretch-triggered increase in ERK1/2-p90(RSK) phosphorylation, (4) lack of stretch-induced Na(+)/H(+) exchanger activation, and (5) abolishment of the slow force response. Our results provide strong evidence that MR activation occurs after myocardial stretch and is a key factor to promote redox-sensitive kinase activation and their downstream consequences.

Cord blood serum-based eye drops: the impact of donor haematological and obstetric factors on the variability of epidermal growth factor levels.

Cord blood serum (CBS)-based eye drops are successfully used in corneal epithelial wound healing and are prepared to supply a known amount of epidermal growth factor (EGF). Product standardisation includes expensive EGF dosage in all cord blood (CB) units. The influence of donor obstetric and haematological characteristics on EGF content was evaluated, to exclude unsuitable CBS and pre-select those CB units able to provide the correct EGF supply for healing corneal wounds. Data were retrospectively collected from 135 donors included in the Emilia Romagna Cord Blood Bank records. Obstetric characteristics, parity and gestational age of the mother, sex, birth weight and Apgar score of the neonate, placental weight, duration of labour and mode of delivery were considered. Haematological characteristics, CD34+ cell number, and total nucleated cell, white blood cell and platelet counts were recorded. EGF content in CB units was estimated by enzyme-linked immunosorbent assay. Statistical evaluation was performed by Mann-Whitney unpaired and Student's t tests. Correlations between variables were evaluated by using Pearson's (r) or Spearman's (ρ) correlation coefficients. EGF content was significantly higher in CBS from donors aged <30 years and after vaginal deliveries as compared with scheduled Caesarean sections (1,386±580 vs 1,106±391 pg/mL; P=0.002). EGF content was significantly correlated with duration of labour (r=0.45; P=0.0001), number of CD34+ cells/mL (r=0.3; P=0.002) particularly in vaginal deliveries (r=0.36; P=0.003), mother's age (-0.25; P=0.005), neonate's birth weight (r=0.27; P=0.005), and total nucleated cell (r=0.25; P=0.006), white cell (r=0.29; P=0.001) and platelet (r=0.24; P=0.009) counts. No significant correlations were found between EGF content and parity, gestational age, placental weight, neonate's sex or Apgar scores. EGF levels are higher in CB units from younger mothers (<30 years), with longer labour duration (>6 hours), and higher CD34+ cell content (>0.05×10(6)/mL). In order to optimise the preparation and costs of CBS-based eye drops, pre-selection of CB units is recommended.

In vitro culture of goat preantral follicles from fetal ovaries

The objective of the present study was to investigate the influence of thyroxin (T4), follicle stimulating hormone (FSH), growth hormone (GH), epidermal growth factor (EGF) and insulin like growth factor-I (IGF-I) individually or in combination on in vitro development of goat fetal preantral follicles (PFs). PFs (100–300μm) were isolated from the fetal ovaries of more than 125 days of gestation and cultured for a period of 6 days. The development of the cultured PFs was assessed by the proportions of follicles exhibiting growth, increase in diameter, antrum formation, and extrusion of oocytes in vitro, if any. In the first experiment, PFs were cultured in tissue culture medium 199 supplemented with different individual concentrations of T4 (0.5, 1 and 2μg/mL), FSH (1, 2 and 4μg/mL), GH (1, 2 and 4mIU/mL), EGF (10, 25 and 50ng/mL) and IGF-I (10, 15 and 20ng/mL). The proportion of PFs exhibiting growth, increase in diameter and antrum formation were highest when the PFs were cultured at T4:1μg/mL, FSH:2μg/mL, GH:1mIU/mL, EGF:25ng/mL or IGF-I:10ng/mL. Among the different individual concentrations of growth factors and hormones, the extrusions of oocytes from cultured PFs were observed only in GH and EGF supplemented media. In the second experiment, the effect of different combinations of the above and hormones and growth factors at their best concentrations as determined in the first experiment was investigated. The average increase in diameter (50.56±3.8μm), the proportion of PFs exhibiting antrum formation (96.54±2.4) and extrusion of oocytes (25.79±1.8) were highest when cultured in T4+FSH+GH+EGF supplemented medium. However, the proportion of extrusion of oocytes was similar in T4+FSH+IGF-I, T4+FSH+GH+IGF-I and T4+FSH+EGF+IGF-I combinations. In conclusion, the in vitro development of goat fetal PFs could be significantly improved when the medium was supplemented with T4+FSH+GH+EGF.

Dietary Nickel Chloride Restrains the Development of Small Intestine in Broilers

The aim of this study was to determine the effects of dietary NiCl2 on the development of the small intestine in broilers by the methods of light microscopy, histochemistry and enzyme-linked immunosorbent assay. A total of 240 one-day-old avian broilers were divided into four groups and fed on a corn-soybean basal diet or the same basal diet supplemented with 300, 600 and 900 mg/kg of nickel chloride (NiCl2) for 42 days. Results showed that the small intestinal villus height, crypt depth and villus/crypt ratio were significantly decreased, and also the small intestinal goblet cells numbers and insulin-like growth factor-1 (IGF-1) and epidermal growth factor (EGF) contents were significantly decreased in the 300-, 600- and 900-mg/kg groups when compared with those of the control group. In conclusion, dietary NiCl2 in excess of 300 mg/kg reduced the villus height, crypt depth, the goblet cells population and the IGF-1 and EGF contents in the small intestine, indicating that the normal development and function of the small intestine were finally impaired in broilers. This study firstly provided the new experimental information for future studies on the effects of NiCl2 on the intestinal function in humans and other animals.