Exosomes encapsulated in hydrogels for effective central nervous system drug delivery.

The targeted delivery of pharmacologically active molecules, metabolites, and growth factors to the brain parenchyma has become one of the major challenges following the onset of neurodegeneration and pathological conditions. The therapeutic effect of active biomolecules is significantly impaired after systemic administration in the central nervous system (CNS) because of the blood-brain barrier (BBB). Therefore, the development of novel therapeutic approaches capable of overcoming these limitations is under discussion. Exosomes (Exo) are nano-sized vesicles of endosomal origin that have a high distribution rate in biofluids. Recent advances have introduced Exo as naturally suitable bio-shuttles for the delivery of neurotrophic factors to the brain parenchyma. In recent years, many researchers have attempted to regulate the delivery of Exo to target sites while reducing their removal from circulation. The encapsulation of Exo in natural and synthetic hydrogels offers a valuable strategy to address the limitations of Exo, maintaining their integrity and controlling their release at a desired site. Herein, we highlight the current and novel approaches related to the application of hydrogels for the encapsulation of Exo in the field of CNS tissue engineering.

MRI diagnosed cardiac lipoma in tuberous sclerosis: a case report with a very rare association.

Tuberous sclerosis is a genetic multisystem disorder characterised by hamartomas in several organs. Cardiac rhabdomyomas are the main features of the disease but lipomas can very rarely be associated. Herein, we present a very rare association of tuberous sclerosis and cardiac lipoma detected by echocardiography and diagnosed as a lipoma via MRI and fat suppression technic, aim to report this very rare association, and emphasise usefulness of MRI in cardiac mass lesions.

An Easy-to-Fabricate Microfluidic Shallow Trench Induced Three-Dimensional Cell Culturing and Imaging (STICI3D) Platform.

Compared to the established monolayer approach of two-dimensional cell cultures, three-dimensional (3D) cultures more closely resemble in vivo models; that is, the cells interact and form clusters mimicking their organization in native tissue. Therefore, the cellular microenvironment of these 3D cultures proves to be more clinically relevant. In this study, we present a novel easy-to-fabricate microfluidic shallow trench induced 3D cell culturing and imaging (STICI3D) platform, suitable for rapid fabrication as well as mass manufacturing. Our design consists of a shallow trench, within which various hydrogels can be formed in situ via capillary action, between and fully in contact with two side channels that allow cell seeding and media replenishment, as well as forming concentration gradients of various molecules. Compared to a micropillar-based burst valve design, which requires sophisticated microfabrication facilities, our capillary-based STICI3D can be fabricated using molds prepared with simple adhesive tapes and razors alone. The simple design supports the easy applicability of mass-production methods such as hot embossing and injection molding as well. To optimize the STICI3D design, we investigated the effect of individual design parameters such as corner radii, trench height, and surface wettability under various inlet pressures on the confinement of a hydrogel solution within the shallow trench using Computational Fluid Dynamics simulations supported with experimental validation. We identified ideal design values that improved the robustness of hydrogel confinement and reduced the effect of end-user dependent factors such as hydrogel solution loading pressure. Finally, we demonstrated cultures of human mesenchymal stem cells and human umbilical cord endothelial cells in the STICI3D to show that it supports 3D cell cultures and enables precise control of cellular microenvironment and real-time microscopic imaging. The easy-to-fabricate and highly adaptable nature of the STICI3D platform makes it suitable for researchers interested in fabricating custom polydimethylsiloxane devices as well as those who are in need of ready-to-use plastic platforms. As such, STICI3Ds can be used in imaging cell-cell interactions, angiogenesis, semiquantitative analysis of drug response in cells, and measurement of transport through cell sheet barriers.

A new association of Oculoauriculovertebral spectrum and persistent fifth aortic arch -double lumen aorta: a case report.

BACKGROUND: Oculo-auriculo-vertebral spectrum is a heterogeneous group of genetic disorder, also known as Goldenhar Syndrome, which has several phenotypic features including craniofacial anomalies, cardiac, vertebral and central nervous system defects. Cardiovascular anomalies include ventricular septal defects, atrial septal defects, patent ductus arteriosus, Tetralogy of Fallot, double outlet right ventricle, aberrant right subclavian artery, coarctation of aorta, transposition of the great arteries, double inlet left ventricle, cor triatriatum, pulmonary artery stenosis, aortic stenosis, persistent left superior vena cava, partially or totally abnormal pulmonary venous return and bicuspid aortic valve. Persistent fifth aortic arch, also named as double lumen aortic arch, is a very rare cardivascular anomaly and usually associate other cardiac defects. CASE PRESENTATION: We present a 7 month old patient with oculo-auriculo-vertebral spectrum signs as facial asymmetry, short neck, choanal atresia, cleft palate, bilateral preauricular skin tags, bilateral hypoplastic ear lobes, epibulbar dermoid cyst, rib, vertebrae and cardiovascular anomalies. Cardiovascular anomalies detected with echocardiography and computed tomography were malalignment ventricular septal defect and double lumen aorta, known as persistent fifth aortic arch. CONCLUSION: Various cardiovascular anomalies may accompany Goldenhar Syndrome. We present a case with persistent fifth aortic arch and Oculo-auriculo-vertebral spectrum and this is a new association that was not reported before in the literature.

The effects of pre-pregnancy obesity and gestational weight gain on maternal lipid profiles, fatty acids and insulin resistance.

OBJECTIVES: Pregnancy is associated with physiological alterations in insulin sensitivity and lipid metabolism. This study investigates the associations between pregestational body mass index (pBMI) and the rate of gestational weight gain (rGWG) in the second trimester with the biomarkers of lipid, fatty acids metabolism and insulin resistance. METHODS: Sixty nine pregnant women followed. The body weights of the pregnant women were measured and blood samples were obtained at 11-14th and 24-28th weeks of pregnancy. Glucose, total cholesterol, triglyceride, HDL cholesterol, LDL cholesterol, insulin levels and fatty acids were measured. Rate of GWG (kg/week) and The Homeostasis Model Assessment for Insulin Resistance (HOMA-IR) were calculated. The pregnant women were stratified according to their pBMI and the 2nd trimester rGWG. RESULTS: The rate of GWG was significantly higher for the group with pBMI<25, compared to the group with pBMI≥25 (p=0.024). Triglyceride, total cholesterol, LDL and HDL cholesterol were significantly increased in the second trimester compared with the first trimester. Palmitic acid, oleic acid, linoleic acid, myristic acid, docosahexaenoic acid (DHA), arachidonic acid (AA), total omega-6 (n - 6) and omega-3 (n - 3) fatty acid levels and n - 6/n - 3 ratio were significantly higher in the second trimester. Glucose was significantly decreased and insulin was increased in the second trimester. In the overweight/obese group; HOMA-IR, insulin, AA, palmitoleic acid and stearic acid were found to be high in comparison to the group with low/normal pBMI. No parameters were associated with rGWG. CONCLUSIONS: The changes in lipid parameters, free fatty acids, insulin and HOMA-IR in the second trimester were compatible with the changes in lipid metabolism and the development of insulin resistance. Pregestational BMI was shown to have a stronger influence on lipid profile, insulin resistance, and fatty acids than rGWG.

An Update on the Role of PCSK9 in Atherosclerosis.

Atherosclerosis is initiated by functional changes in the endothelium accompanied by accumulation, oxidation, and glycation of LDL-cholesterol in the inner layer of the arterial wall and continues with the expression of adhesion molecules and release of chemoattractants. PCSK9 is a proprotein convertase that increases circulating LDL levels by directing hepatic LDL receptors into lysosomes for degradation. The effects of PCSK9 on hepatic LDL receptors and contribution to atherosclerosis via the induction of hyperlipidemia are well defined. Monoclonal PCSK9 antibodies that block the effects of PCSK9 on LDL receptors demonstrated beneficial results in cardiovascular outcome trials. In recent years, extrahepatic functions of PCSK9, particularly its direct effects on atherosclerotic plaques have received increasing attention. Experimental trials have revealed that PCSK9 plays a significant role in every step of atherosclerotic plaque formation. It contributes to foam cell formation by increasing the uptake of LDL by macrophages via scavenger receptors and inhibiting cholesterol efflux from macrophages. It induces the expression of inflammatory cytokines, adhesion molecules, and chemoattractants, thereby increasing monocyte recruitment, inflammatory cell adhesion, and inflammation at the atherosclerotic vascular wall. Moreover, low shear stress is associated with increased PCSK9 expression. PCSK9 may induce endothelial cell apoptosis and autophagy and stimulate the differentiation of smooth muscle cells from the contractile phenotype to synthetic phenotype. Increasing evidence indicates that PCSK9 is a molecular target in the development of novel approaches toward the prevention and treatment of atherosclerosis. This review focuses on the molecular roles of PCSK9 in atherosclerotic plaque formation.

Is N-terminal pro-brain natriuretic peptide a reliable marker for body fluid status in children with chronic kidney disease?

INTRODUCTION: Brain natriuretic peptides, released in response to left ventricular stress, have a strong prognostic value in dialysis patients. However, their role in detecting abnormalities of fluid status is under debate; the relationship between volume status and brain natriuretic peptides (BNPs) differs among various studies. The aim of our study was to evaluate the clinical utility of N-terminal proBNP in the assessment of fluid status and cardiovascular risk in this setting. MATERIAL AND METHODS: The study included 65 children: 10 pre-dialysis, 13 hemodialysis, 12 peritoneal dialysis patients and 30 healthy controls. Volume status was determined by multifrequency bioimpedance and NT-pro-BNP, as well as echocardiography to estimate the left ventricle structure and function. RESULTS: The median log NT-proBNP values of hemodialysis and peritoneal dialysis patients were 3.66 (2.05-4.90) and 3.57 (2.51-4.13) pg/ml, respectively, and significantly higher compared with the control group (p < 0.001, p < 0.001). On simple correlation, NT-proBNP was correlated with markers of volume overload and cardiac dysfunction. On multivariate regression analysis, only left ventricle mass index (ß = 0.402, p = 0.003) and left atrium diameter (ß = 0.263, p = 0.018) were independently associated with NT-proBNP (adjusted R 2 of the model: 0.707, p < 0.001). CONCLUSIONS: Our research suggested that NT-proBNP, which was correlated with LV systolic and diastolic dysfunction and fluid overload as assessed by bioimpedance, can be used to evaluate cardiovascular states in a chronic kidney disease (CKD) population. From the early stages of CKD, periodic monitoring of NT-proBNP levels may be essential for early detection of patients with high risk of cardiovascular events, and for taking preventive intervention as soon as possible.

Cardiac functions in children with steroid-sensitive nephrotic syndrome.

BACKGROUND: The aim of the present study was to evaluate the presence of cardiac systolic and diastolic dysfunction in pediatric patients with steroid-sensitive nephrotic syndrome (NS). METHODS: The study population consisted of 19 patients with debut-relapse of NS aged 1-18 years and 30 sex and age-matched healthy controls. Blood and urine samples, two M-mode conventional echocardiograms and tissue Doppler velocity imaging were evaluated in both attack and remission periods. RESULTS: With regard to conventional pulse wave Doppler (cPWD), steroid-sensitive NS patients (both in debut / relapse and in remission periods) had a higher peak of late diastolic flow velocities (A peak), and patients in debut / relapse had a lower E/A ratio than the control group, indicating diastolic dysfunction (overall P = 0.003 and P = 0.006, respectively). Based on tissue Doppler velocity imaging echocardiography results, patients in debut/relapse had a higher A' and a lower E'/A' ratio (overall P < 0.001 and P = 0.001, respectively). There was also a significant difference in the cPWD E/TDI E' ratio between the patients showing an increased cPWD E/TDI E' ratio in remission periods compared to in debut/relapse periods (P = 0.09). The albumin levels were positively correlated with E'/A' and E/ E' ratio (r = 0.609; P = 0.007, r = 0.472; P = 0.041 respectively). CONCLUSIONS: Systolic cardiac functions are preserved but diastolic functions are affected in steroid-sensitive NS patients both in debut/relapse and in remission periods in a relatively short time. The persistence of left ventricular (LV) dysfunction during the remission period requires special attention during the follow up for early detection of cardiac abnormalities.

The anti-angiogenic potential of (±) gossypol in comparison to suramin.

Cotton, a staple fiber that grows around the seeds of the cotton plants (Gossypium), is produced throughout the world, and its by products, such as cotton fibers, cotton-seed oil, and cottonseed proteins, have a variety of applications. Cotton-seed contains gossypol, a natural phenol compound. (±)-Gossypol is a yellowish polyphenol that is derived from different parts of the cotton plant and contains potent anticancer properties. Tumor growth and metastasis are mainly related to angiogenesis; therefore, anti-angiogenic therapy targets the new blood vessels that provide oxygen and nutrients to actively proliferating tumor cells. The aim of the present study was to evaluate the anti-angiogenic potential of (±)-gossypol in vitro. (±)-Gossypol has anti-proliferative effects on cancer cell lines; however, its anti-angiogenic effects on normal cells have not been studied. Anti-proliferative activities of gossypol assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, anti-angiogenic activities using tube formation assay, and cell migration inhibition capability using a wound-healing assay on human umbilical vein endothelial cells (HUVECs) were revealed. (±)-Gossypol displayed the following potent anti-angiogenic activities in vitro: it inhibited the cell viability of HUVECs, it inhibited the migration of HUVECs, and disrupted endothelial tube formation in a dose-dependent manner. In addition, the anti-angiogenic effects of (±)-gossypol were investigated in ovo in a model using a chick chorioallantoic membrane (CAM). Decreases in capillary density were assessed and scored. (±)-Gossypol showed dose-dependent anti-angiogenic effects on CAM. These findings suggest that (±)-gossypol can be used as a new anti-angiogenic agent.

The role of bioelectrical impedance analysis, NT-ProBNP and inferior vena cava sonography in the assessment of body fluid volume in children with nephrotic syndrome / El papel del análisis de impedancia bioeléctrica, la NT-proBNP y la ecografía de vena cava inferior en la evaluación del volumen de líquidos corporales en niños con síndrome nefrótico

Background: Assessment of volume status and differentiating ’underfill ’ and ’overfill ’ edema is essential in the management of patients with nephrotic syndrome (NS). Objectives: Our aim was to evaluate the volume status of NS patients by using different methods and to investigate the utility of bioelectrical impedance analysis (BIA) in children with NS. Methods: The hydration status of 19 patients with NS (before treatment of NS and at remission) and 25 healthy controls was assessed by multifrequency BIA, serum N-terminal-pro-brain natriuretic peptide (NT-proBNP) levels, inferior vena cava (IVC) diameter, left atrium diameter (LAD) and vasoactive hormones. Results: Renin, aldosterone levels, IVC diameter and LAD were not statistically different between the groups. NT-proBNP values were statistically higher in the attack period compared to remission and the control group (p=0.005 for each). Total body water (TBW), overhydration (OH) and extracellular water (ECW) estimated by the BIA measurement in the attack group was significantly higher than that of the remission group and controls. There were no significant correlations among volume indicators in group I and group II. However, significant correlations were observed between NT-proBNP and TBW/BSA (p=0.008), ECW/BSA (p=0.003) and ECW/ICW (p=0.023) in the healthy group. TBW was found to be higher in patients with NS in association with increased ECW but without any change in ICW. NT-proBNP values were higher in patients during acute attack than during remission. Conclusions: Our findings support the lack of hypovolaemia in NS during acute attack. In addition, BIA is an easy-to-perform method for use in routine clinical practice to determine hydration status in patients with NS (AU)

Antecedentes: La evaluación del estado volumétrico y la diferenciación entre edema «por sobrellenado» y «por infrallenado» es fundamental en el manejo de los pacientes con síndrome nefrótico (SN). Objetivos: Nuestro objetivo fue evaluar el estado volumétrico de los pacientes con SN mediante el uso de diversos métodos y estudiar la utilidad del análisis de impedancia bioeléctrica (BIA) en niños con SN. Métodos: Se evaluó el estado de hidratación de 19 pacientes con SN (antes del tratamiento y en la remisión) y de 25 controles sanos mediante BIA multifrecuencia, valores plasmáticos de la fracción N-terminal del péptido natriurético cerebral (NT-proBNP), diámetro de la vena cava inferior, diámetro de la aurícula izquierda y hormonas vasoactivas. Resultados: La renina, los niveles de aldosterona, el diámetro de la vena cava inferior y el de la aurícula izquierda no fueron estadísticamente diferentes entre los grupos. Los valores de la NT-proBNP fueron estadísticamente más altos en el período de crisis que en el momento de remisión y que en el grupo de control (p=0,005 en cada uno). El agua total corporal (TBW), la hiperhidratación y el agua extracelular (ECW) estimada mediante la medición del BIA en el grupo de crisis fue considerablemente mayor que la del grupo de remisión y los controles. No hubo correlaciones importantes entre los indicadores de volumen en el grupo I y en el grupo II. Sin embargo, se observaron correlaciones considerables entre NT-proBNP y TBW/BSA (p=0,008), ECW/BSA (p=0,003) y ECW/ICW (p=0,023) en el grupo sano. Se encontró que TBW fue mayor en los pacientes con SN relacionado con el aumento de ECW, pero sin ningún cambio en ICW. Los valores de la NT-proBNP fueron más altos en los pacientes durante la crisis aguda que durante la remisión. Conclusiones: Nuestros hallazgos apoyan la falta de hipovolemia en el SN durante la crisis aguda. Además, BIA es un método fácil de utilizar en la práctica clínica habitual para determinar el estado de hidratación en pacientes con SN (AU)

A case of brucellosis presenting with pericardial and pleural effusion.

Brucellosis is a worldwide zoonotic infection with a diverse clinical presentation. Pericardial and pleural involvement is rare in brucellosis. There is no presentation with pleural and pericardial effusion in childhood brusellosis. In endemic countries Brucellosis must thought as an unknown etiology of pericardial and pleural effusion.

The role of bioelectrical impedance analysis, NT-ProBNP and inferior vena cava sonography in the assessment of body fluid volume in children with nephrotic syndrome.

BACKGROUND: Assessment of volume status and differentiating "underfill" and "overfill" edema is essential in the management of patients with nephrotic syndrome (NS). OBJECTIVES: Our aim was to evaluate the volume status of NS patients by using different methods and to investigate the utility of bioelectrical impedance analysis (BIA) in children with NS. METHODS: The hydration status of 19 patients with NS (before treatment of NS and at remission) and 25 healthy controls was assessed by multifrequency BIA, serum N-terminal-pro-brain natriuretic peptide (NT-proBNP) levels, inferior vena cava (IVC) diameter, left atrium diameter (LAD) and vasoactive hormones. RESULTS: Renin, aldosterone levels, IVC diameter and LAD were not statistically different between the groups. NT-proBNP values were statistically higher in the attack period compared to remission and the control group (p=0.005 for each). Total body water (TBW), overhydration (OH) and extracellular water (ECW) estimated by the BIA measurement in the attack group was significantly higher than that of the remission group and controls. There were no significant correlations among volume indicators in group I and group II. However, significant correlations were observed between NT-proBNP and TBW/BSA (p=0.008), ECW/BSA (p=0.003) and ECW/ICW (p=0.023) in the healthy group. TBW was found to be higher in patients with NS in association with increased ECW but without any change in ICW. NT-proBNP values were higher in patients during acute attack than during remission. CONCLUSIONS: Our findings support the lack of hypovolaemia in NS during acute attack. In addition, BIA is an easy-to-perform method for use in routine clinical practice to determine hydration status in patients with NS.

Comparison of culture media indicates a role for autologous serum in enhancing phenotypic preservation of rabbit limbal stem cells in explant culture.

In this study, we aimed to compare the effects of six different cell culture media and autologous serum (AS) on the phenotypic characteristics of rabbit limbal epithelial stem cells (LESC) cultivated on porous polyethylene terephthalate (PET) membranes. Limbal explants from rabbit corneas were grown on PET membrane inserts in five different media: DMEM-F12 with fetal bovine serum (FBS) (DMEM-F12-FBS), with pluripotin (DMEM-F12-pluripotin) and with autologous serum (DMEM-F12-AS), Epilife, Keratinocyte Serum Free Medium (KSFM) and Defined-Keratinocyte Serum Free Medium. The effects of different media were evaluated by total cell yield from explants, measuring the expression of proteins by immunofluorescence and gene expression by Real Time PCR. In all five media tested, most of the limbal epithelial cells (LEC) which proliferated from explants were positive for cytokeratin (CK) 14 (85-90%), indicating that all five media support the growth of LESC from explants. The expression of differentiation markers; CK 3 and 12 was highest in DMEM-F12-FBS (56%), was lower in Epilife and KSFM (26 and 19%, respectively), with the lowest values (13%) obtained in DMEM-F12-AS. Gene expression of limbal cultures on PET membrane inserts was compared to fresh limbal tissue. In DMEM-F12-FBS, DMEM-F12-pluripotin, and DMEM-F12-AS, expression of potential LESC markers CXCR4 and polycomb complex protein BMI-1 were similar to limbal tissue. DMEM-F12 with 10% AS maintained a higher percentage of potential stem cell marker genes and lower expression of genes involved in differentiation compared to Epilife or KSFM. Our study shows that rabbit LEC can be cultivated on PET inserts using DMEM-F12 with autologous serum without a requirement for amniotic membrane or feeder cells.

Corneal recovery in a rabbit limbal stem cell deficiency model by autologous grafts of tertiary outgrowths from cultivated limbal biopsy explants.

PURPOSE: To determine the corneal regenerative capacity of sequentially generated primary, secondary, and tertiary limbal explant outgrowths in a limbal stem cell deficiency (LSCD) surgical model. METHODS: Two-millimeter-long limbal shallow biopsies were surgically excised from the upper quadrant of the right eye of rabbits and set on preserved amniotic membrane for explant culture. After the generation of primary outgrowth, the biopsies were sequentially transferred to new amniotic membrane to generate secondary and then tertiary outgrowths. Eighteen rabbits were subjected to a 360° limbal peritomy extending into the scleral zone and combined with superficial keratectomy of the corneal periphery and thorough mechanical debridement of the central cornea in their left eye. Right eye outgrowths, six of each generation, were engrafted on the ocular surface. Clinical outcomes (neovascularization, corneal clarity, and corneal fluorescein staining) were graded after 6 months. Post-mortem corneas were compared with histology, immunochemistry for p63 and Krt3, ABCG2-dependent dye exclusion, and capacity for outgrowths in explant culture. RESULTS: Immunohistology and western blot of the outgrowths for p63 and Krt3 indicated no differences in expression between the primary and tertiary outgrowths for these two markers of growth and differentiation. Clinically, all rabbits treated with amniotic membrane alone developed severe LSCD. Most rabbits grafted with cell outgrowths from all three outgrowth generations achieved stable (>6 months) recovery of the ocular surface. There were partial failures of grafts performed with two secondary and tertiary outgrowths. However, Kruskal-Wallis statistical analysis of the clinical scores yielded no significant difference between the three groups (p=0.524). Histology showed full anatomic recovery of grafts made with primary and tertiary outgrowths. Krt3 and p63 expression throughout the whole limbal corneal epithelium with primary or tertiary outgrowths was not distinguishable from each other. The percentage of dye-excluding cells present within this zone and the capacity of the explant epithelial outgrowth of the regenerated peripheral corneal zone were also on par with those of the donor corneas. The Krt3-negative cells that characterize the basal epithelial layer of the normal limbus could not be found in any regenerated cornea from the primary to tertiary outgrowths. CONCLUSIONS: Our results demonstrate that in rabbits post-primary explant outgrowths retain the capacity for LSCD recovery found in primary explants.

Evaluation of apoptotic molecular pathways for smooth muscle cells isolated from thoracic aortic aneurysms in response to oxidized sterols.

Oxysterols, oxygenated derivatives of cholesterol, are found abundantly in the plasma and atherosclerotic plaques, a common risk factor for thoracic aortic aneurysms (TAAs). Among the oxysterols, namely 7-ketocholesterol (7-KC) and 25-hydroxycholesterol (25-OHC), lead both to induction of reactive oxygen species (ROS) in cells and to apoptosis in smooth muscle cells (SMCs) probably due to increased oxidative stress. Since loss of SMCs through apoptosis is a major event in TAA formation, it is important to understand the molecular pathways of apoptosis in response to ROS in TAAs. Very little is known about the effect of oxysterols on TAA SMCs. Therefore, we investigated molecular pathways participating in the oxysterol induced cell death of TAAs. Our results showed that TAA SMCs died mainly as a result of apoptosis as suggested by cellular shrinkage, blebbing, DNA condensation/fragmentation in response to oxysterol treatment. There was no significant difference in oxysterol induced cell death between TAA and control SMCs. Addition of antioxidant molecules prevented cell death, hence ROS appears to be involved in the apoptosis of these cells. While oxysterol treatment increased caspase 3 activity, cell death was not rescued in its absence. Efficient silencing of other targets including apoptotic proteins (p53, Bax), and survival proteins (Akt1, Akt2) showed that apoptosis can occur through p53, and Bax independent pathways. Silencing Akt1 or Akt2 did not lead to further cell death. These results indicate that oxysterols can induce several cell death pathways in TAA SMCs.

Proteomic study of the microdissected aortic media in human thoracic aortic aneurysms.

Aortic aneurysm is a complex multifactorial disease, and its molecular mechanism is not understood. In thoracic aortic aneurysm (TAA), the expansion of the aortic wall is lead by extracellular matrix (ECM) degeneration in the medial layer, which leads to weakening of the aortic wall. This dilatation may end in rupture and-if untreated-death. The aortic media is composed of vascular smooth muscle cells (VSMCs) and proteins involved in aortic elasticity and distensibility. Delineating their functional and quantitative decrease is critical in elucidating the disease causing mechanisms as well as the development of new preventive therapies. Laser microdissection (LMD) is an advanced technology that enables the isolation of the desired portion of tissue or cells for proteomics analysis, while preserving their integrity. In our study, the aortic media layers of 36 TAA patients and 8 controls were dissected using LMD technology. The proteins isolated from these tissue samples were subjected to comparative proteomic analysis by nano-LC-MS/MS, which enabled the identification of 352 proteins in aortic media. Among these, 41 proteins were differentially expressed in the TAA group with respect to control group, and all were downregulated in the patients. Of these medial proteins, 25 are novel, and their association with TAA is reported for the first time in our study. Subsequent analysis of the data by ingenuity pathway analysis (IPA) shows that the majority of differentially expressed proteins were found to be cytoskeletal-associated proteins and components of the ECM which are critical in maintaining aortic integrity. Our results indicate that the protein expression profile in the aortic media from TAA patients differs significantly from controls. Further analysis of the mechanism points to markers of pathological ECM remodeling, which, in turn, affect VSMC cytosolic structure and architecture. In the future, the detailed investigation of the differentially expressed proteins may provide insight into the elucidation of the pathological processes underlying aneurysms.

Alginate/polyoxyethylene and alginate/gelatin hydrogels: preparation, characterization, and application in tissue engineering.

Hydrogels are attractive biomaterials for three-dimensional cell culture and tissue engineering applications. The preparation of hydrogels using alginate and gelatin provides cross-linked hydrophilic polymers that can swell but do not dissolve in water. In this work, we first reinforced pure alginate by using polyoxyethylene as a supporting material. In an alginate/PEO sample that contains 20 % polyoxyethylene, we obtained a stable hydrogel for cell culture experiments. We also prepared a stable alginate/gelatin hydrogel by cross-linking a periodate-oxidized alginate with another functional component such as gelatin. The hydrogels were found to have a high fluid uptake. In this work, preparation, characterization, swelling, and surface properties of these scaffold materials were described. Lyophilized scaffolds obtained from hydrogels were used for cell viability experiments, and the results were presented in detail.

Evaluation of children with Crimean-Congo hemorrhagic fever in the central Blacksea region.

BACKGROUND: Crimean-Congo hemorrhagic fever (CCHF) is endemic in some regions of our country. It is seen in all age groups; however, its prevalance is low in children. The studies on CCHF have been mostly in adults. The aim of this study was to evaluate the epidemiologic, demographic, clinical and laboratory findings of children with CCHF. METHODS: Between May 2008 and September 2011, the medical records of patients who were admitted to the Children Infectious Diseases Service of Ondokuz Mayis University School of Medicine with positive blood IgM by enzyme-linked immunosorbent assay or polymerase chain reaction positive for CCHF were retrospectively evaluated. Epidemiologic and demographic features, clinical and laboratory data and therapy were recorded. RESULTS: Fifty-four patients with the diagnosis of CCHF were recorded between May 2008 and September 2011. Main symptoms during hospital admission were fever (98%), vomiting (59%), headache (39%), nausea (39%), diarrhea (22%), abdominal pain (22%), bleeding (22%) and rash (20%). During admission, thrombocytopenia was found in 74%, elevated aspartate aminotransferase in 61%, leucopenia in 57%, elevated creatine kinase (33%) and alanine aminotransaminase (29%), and prolonged prothrombin time and partial thromboplastine time in 28% were noted. Thirty-nine patients received ribavirin treatment. During clinical follow up, bradycardia was recorded in 18 patients (33%) all of whom received ribavirin treatment. One patient died. CONCLUSIONS: This study reports the largest series of children with CCHF and the first to describe bradycardia associated with ribavirin therapy.

Chitosan/alginate crosslinked hydrogels: preparation, characterization and application for cell growth purposes.

Chitosan hydrogels may be formed by various mechanisms. In this study, we aimed to form hybrid polymer networks of chitosan with alginate using a crosslinker which enabled the covalent binding of the two macromolecules. The structural and thermal characterization of these hydrogels was performed by using Fourier transform infrared (FTIR) and differential scanning calorimeter (DSC). The morphological analysis of the crosslinked material was investigated by scanning electron microscopy (SEM) and a scanning probe microscope with atomic force microscope (AFM) attachment. The swelling properties of these gels were analyzed in water and in phosphate buffered saline (PBS) solution. The presence of alginate in a chitosan/alginate hydrogel was shown to support the hydrogel stability. Compared to chitosan/alginate (1/2) hydrogel prepared with 1wt% DCC, the swelling of chitosan/alginate (1/2) hydrogels prepared with 3wt% DCC was limited. To measure the degree of cell proliferation, the hydrogels were seeded with L929 mouse fibroblasts and cell numbers measured by neutral red uptake assay. The cell attachment was also followed by (SEM) photography. It was observed that chitosan/alginate (1/2) hydrogels with 1wt% (DCC) provides a better environment for cell attachment and proliferation. This study presents functional hydrogel formation by crosslinked chitosan and alginate, a novel biomaterial which also supports cell growth.

Controlled release of imatinib mesylate from PLGA microspheres inhibit craniopharyngioma mediated angiogenesis.

Poly(lactic-co-glycolic acid) microspheres loaded with imatinib mesylate has been developed as a new therapeutic strategy to prevent craniopharyngioma recurrence. Microspheres composed of different lactic/glycolic acid ratios, molecular weights and drug compositions were synthesized and loaded with imatinib mesylate by modified double-emulsion/solvent evaporation technique and subsequently characterized by particle-size distribution, scanning electron microscopy, encapsulation efficiency and in vitro drug release. Inhibitory potential of imatinib containing microspheres on tumor neovascularization was investigated on craniopharyngioma tumor samples by rat cornea angiogenesis assay. Results showed that microspheres in different LA:GA ratios [LA:GA 50:50 (G50), 75:25 (G25), 85:15 (G15)] considerably reduced neovascularization induced by recurrent tumor samples in an in vivo angiogenesis assay (P < 0.01). Our data indicate that local delivery of imatinib mesylate to the post-surgical tumoral cavity using biodegradable microspheres may be a promising biologically selective approach to prevent the recurrence of craniopharyngiomas, via inhibition of neovascularization.