Evaluation of tumour vascularisation in two rat sarcoma models for studying isolated lung perfusion. Injection route determines the origin of tumour vessels.

Isolated cytostatic lung perfusion (ILP) is an attractive technique allowing delivery of a high-dose of cytostatic agents to the lungs while limiting systemic toxicity. In developing a rat model of ILP, we have analysed the effect of the route of tumour cell injection on the source of tumour vessels. Pulmonary sarcomas were established by injecting a sarcoma cell suspension either by the intravenous (i.v.) route or directly into the lung parenchyma. Ink perfusion through either pulmonary artery (PA) or bronchial arteries (BA) was performed and the characteristics of the tumour deposits defined. i.v. and direct injection methods induced pulmonary sarcoma nodules, with similar histological features. The intraparenchymal injection of tumour cells resulted in more reliable and reproducible tumour growth and was associated with a longer survival of the animals. i.v. injected tumours developed a PA-derived vascular tree whereas directly injected tumours developed a BA-derived vasculature.

FOXC2 controls formation and maturation of lymphatic collecting vessels through cooperation with NFATc1.

The mechanisms of blood vessel maturation into distinct parts of the blood vasculature such as arteries, veins, and capillaries have been the subject of intense investigation over recent years. In contrast, our knowledge of lymphatic vessel maturation is still fragmentary. In this study, we provide a molecular and morphological characterization of the major steps in the maturation of the primary lymphatic capillary plexus into collecting lymphatic vessels during development and show that forkhead transcription factor Foxc2 controls this process. We further identify transcription factor NFATc1 as a novel regulator of lymphatic development and describe a previously unsuspected link between NFATc1 and Foxc2 in the regulation of lymphatic maturation. We also provide a genome-wide map of FOXC2-binding sites in lymphatic endothelial cells, identify a novel consensus FOXC2 sequence, and show that NFATc1 physically interacts with FOXC2-binding enhancers. As damage to collecting vessels is a major cause of lymphatic dysfunction in humans, our results suggest that FOXC2 and NFATc1 are potential targets for therapeutic intervention.

Fenilefrina intracamerular en el síndrome del iris flácido intraoperatorio

La incidència d’hipertròfia benigna de pròstata és aproximadament d’un 50 % en pacients majors de 50 anys. La Tamsulosina és el medicament més prescrit per aquesta dolència i la principal causa del síndrome d’iris flàccid intraoperatori a la cirurgia de cataractes. Els nostres dos estudis han sigut; per una banda, avaluar la toxicitat corneal i afectació cardíaca de Fenilefrina intracamerular a una concentració de 2,5% respecte la pauta de dilatació tòpica estàndard al nostre centre, i per l’altra, comparar l’ efectivitat i diferència al recompte endotelial de Fenilefrina intracamerular a una concentració de 2,5% respecte a una altra concentració del 1,66 %, mesurant els seus efectes en diverses variables.

Evaluation of tumor vascularisation in two rat sarcoma models for studying isolated lung perfusion : Injection route determines the origin of tumour vessels

Résumé Introduction: La perfusion isolée cytostatique du poumon est une technique attractive qui permet l'administration des doses élevées d'un agent cytostatique tout en épargnant dans la mesure du possible la circulation systémique. Cependant, la perfusion de l'artère pulmonaire risque d'épargner le territoire pulmonaire vascularisé par l'intermédiaire des artères bronchiques, ce qui pourrait diminuer l'efficacité de ce traitement au cas où la lésion ciblée est vascularisée par les artères bronchiques. Ce travail est destiné au développement d'un modèle tumoral au niveau des poumons de rongeur (rat) porteur d'un sarcome pulmonaire afin de déterminer si la voie d'injection des cellules tumorales (intraveineuse, versus intratumorale) influencera la vascularisation des tumeurs (provenant du système artères pulmonaires ou artères bronchiques). Méthod: Des tumeurs de sarcomes pulmonaires ont été générées par injection d'une suspension cellulaire de sarcome, soit par injection intraveineuse, soit directement dans le parenchyme pulmonaire par thoracotomie. Ensuite, une perfusion isolée du poumon porteur de la tumeur à l'aide de l'encre a été effectuée, soit par l'artère pulmonaire, soit par le système des artères bronchiques. La distribution de l'encre dans les vaisseaux tumoraux ainsi que dans les vaisseaux non tumoraux du poumon adjacent a été investiguée à l'aide d'une analyse histologique des poumons perfusés. Résultat: L'administration intraveineuse et intratumorale de la suspension de cellules tumorales résulte en des tumeurs similaires sur le plan histologique. Néanmoins, l'injection intra-parenchymateuse démontre des tumeurs plus homogènes et avec un développement plus prédictible, était associée à une survie plus longue qu'après injection intraveineuse. Les analyses histologiques après perfusion isolée à l'aide de l'encre démontre que les tumeurs résultant de l'injection intraveineuse ont développé une vascularisation se basant sur le système d'artères pulmonaires tandis que les tumeurs émergeant après injection intraparenchymateuse ont développé une vascularisation provenant du système des artères bronchiques. Conclusion: Ce travail démontre pour la première fois l'importance du mode de génération de tumeurs pulmonaires en ce qui concerne leur future vascularisation, ce qui pourrait avoir un impact sur leur traitement par perfusion isolée du poumon. Abstract Isolated cytostatic lung perfusion (ILP) is an attractive technique allowing delivery of a high-dose of cytostatic agents to the lungs while limiting systemic toxicity. In developing a rat model of ILP, we have analysed the effect of the route of tumour cell injection on the source of tumour vessels. Pulmonary sarcomas were estab¬lished by injecting a sarcoma cell suspension either by the intravenous (i.v.) route or directly into the lung paren¬chyma. Ink perfusion through either pulmonary artery (PA) or bronchial arteries (BA) was performed and the characteristics of the tumour deposits defined. i.v. and direct injection methods induced pulmonary sarcoma nodules, with similar histological features. The intraparenchymal injection of tumour cells resulted in more reli¬able and reproducible tumour growth and was associat¬ed with a longer survival of the animals. i.v. injected tumours developed a PA-derived vascular tree whereas directly injected tumours developed a BA-derived vasculature.

Angiotensin II is an endogenous neurotransmitter for rat and human mesenteric resistance blood vessels

Angiotensin II (Ang II) is one of the most potent vasoconstrictors. We document here the innervation of rat and human mesenteric resistance arteries (MRA) by angiotensinergic neurons of the rat and human sympathetic coeliac ganglia. Angiotensinogen (Ang-N)-mRNA and angiotensin converting enzyme-mRNA but no renin-mRNA were detected by using quantitative real time polymerase chain reaction in total RNA extracts of rat coeliac ganglia. In the same extracts, cathepsin D-mRNA was detected: This protease also cleaves Ang I from Ang-N and could therefore account for the generation of neuronal Ang peptides in the absence of renin. In situ hybridization confirmed the presence of Ang-N-mRNA in the cytoplasm of rat coeliac ganglia. By using solid-phase extraction, high performance liquid chromatography and subsequent radioimmunoassay, Ang II and its metabolites were detected in rat and also in human coeliac ganglia. Immunoreactivity for Ang II was demonstrated in rat and human coeliac ganglia neurons and their projections innervating MRA. In addition, segmental angiotensinergic innervation of MRA was also observed. By means of confocal laser scanning microscopy we were able to demonstrate the presence of angiotensinergic synapses en passant along side of vascular smooth muscle cells. Our findings could indicate that Ang II is synthesized inside the neurons of sympathetic coeliac ganglia and may act as an endogenous neurotransmitter locally in MRA.

Notch signaling in the pigmented epithelium of the anterior eye segment promotes ciliary body development at the expense of iris formation.

The ciliary body and iris are pigmented epithelial structures in the anterior eye segment that function to maintain correct intra-ocular pressure and regulate exposure of the internal eye structures to light, respectively. The cellular and molecular factors that mediate the development of the ciliary body and iris from the ocular pigmented epithelium remain to be fully elucidated. Here, we have investigated the role of Notch signaling during the development of the anterior pigmented epithelium by using genetic loss- and gain-of-function approaches. Loss of canonical Notch signaling results in normal iris development but absence of the ciliary body. This causes progressive hypotony and over time leads to phthisis bulbi, a condition characterized by shrinkage of the eye and loss of structure/function. Conversely, Notch gain-of-function results in aniridia and profound ciliary body hyperplasia, which causes ocular hypertension and glaucoma-like disease. Collectively, these data indicate that Notch signaling promotes ciliary body development at the expense of iris formation and reveals novel animal models of human ocular pathologies.

Tenascin-W is a specific marker of glioma-associated blood vessels and stimulates angiogenesis in vitro.

The microenvironment hosting a tumor actively participates in regulating tumor cell proliferation, migration, and invasion. Among the extracellular matrix proteins enriched in the stroma of carcinomas are the tenascin family members tenascin-C and tenascin-W. Whereas tenascin-C overexpression in gliomas is known to correlate with poor prognosis, the status of tenascin-W in brain tumors has not been investigated so far. In the present study, we analyzed protein levels of tenascin-W in 38 human gliomas and found expression of tenascin-W in 80% of the tumor samples, whereas no tenascin-W could be detected in control, nontumoral brain tissues. Double immunohistochemical staining of tenascin-W and von Willebrand factor revealed that tenascin-W is localized around blood vessels, exclusively in tumor samples. In vitro, the presence of tenascin-W increased the proportion of elongated human umbilical vein endothelial cells (HUVECs) and augmented the mean speed of cell migration. Furthermore, tenascin-W triggered sprouting of HUVEC spheroids to a similar extent as the proangiogenic factor tenascin-C. In conclusion, our study identifies tenascin-W as a candidate biomarker for brain tumor angiogenesis that could be used as a molecular target for therapy irrespective of the glioma subtype.-Martina, E., Degen, M., Rüegg, C., Merlo, A., Lino, M. M., Chiquet-Ehrismann, R., Brellier, F. Tenascin-W is a specific marker of glioma-associated blood vessels and stimulates angiogenesis in vitro.

Effects of triamcinolone acetonide on vessels of the posterior segment of the eye.

PURPOSE: This study investigates the effects of triamcinolone acetonide (TA) on retinal endothelial cells in vitro and explores the potential vascular toxic effect of TA injected into the vitreous cavity of rats in vivo. METHODS: Subconfluent endothelial cells were treated with either 0.1 mg/ml or 1 mg/ml TA in 1% ethanol. Control cells were either untreated or exposed to 1% ethanol. Cell viability was evaluated at 24 h, 72 h, and five days using the tetrazolium 3-(4,5-dimethylthiazol-2-yl)-2,5 phenyltetrazolium bromide test (MTT) and lactate dehydrogenase (LDH) assays. Cell proliferation was evaluated by 5-bromo-2-deoxyuridine (BrdU) test. Apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling assay (TUNEL assay), annexin-binding, and caspase 3 activation. Caspase-independent cell deaths were investigated by immunohistochemistry using antibodies against apoptosis inducing factor (AIF), cytochrome C, microtubule-associated protein (MAP)-light chain 3 (MAP-LC3), and Leukocyte Elastase Inhibitor/Leukocyte Elastase Inhibitor-derived DNase II (LEI/L-DNase II). In vivo, semithin and ultrathin structure analysis and vascular casts were performed to examine TA-induced changes of the choroidal vasculature. In addition, outer segments phagocytosis assay on primary retinal pigment epithelium (RPE) cells was performed to assess cyclooxygenase (COX-2) and vascular endothelial growth factor (VEGF) mRNAs upregulation with or without TA. RESULTS: The inhibitory effect of TA on cell proliferation could not explain the significant reduction in cell viability. Indeed, TA induced a time-dependent reduction of bovine retinal endothelial cells viability. Annexin-binding positive cells were observed. Cytochrome C was not released from mitochondria. L-DNase II was found translocated to the nucleus, meaning that LEI was changed into L-DNase II. AIF was found nuclearized in some cells. LC3 labeling showed the absence of autophagic vesicles. No autophagy or caspase dependent apoptosis was identified. At 1 mg/ml TA induced necrosis while exposure to lower concentrations for 3 to 5 days induced caspase independent apoptosis involving AIF and LEI/L-DNase II. In vivo, semithin and ultrathin structure analysis and vascular casts revealed that TA mostly affected the choroidal vasculature with a reduction of choroidal thickness and increased the avascular areas of the choriocapillaries. Experiments performed on primary RPE cells showed that TA downregulates the basal expression of COX-2 and VEGF and inhibits the outer segments (OS)-dependent COX-2 induction but not the OS-dependent VEGF induction. CONCLUSIONS: This study demonstrates for the first time that glucocorticoids exert direct toxic effect on endothelial cells through caspase-independent cell death mechanisms. The choroidal changes observed after TA intravitreous injection may have important implications regarding the safety profile of TA use in human eyes.

Correlation between vasoconstrictor roles and mRNA expression of alpha1-adrenoceptor subtypes in blood vessels of genetically engineered mice.

We examined the contribution of each alpha(1)-adrenoceptor (AR) subtype in noradrenaline (NAd)-evoked contraction in the thoracic aortas and mesenteric arteries of mice. Compared with the concentration-response curves (CRCs) for NAd in the thoracic aortas of wild-type (WT) mice, the CRCs of mutant mice showed a significantly lower sensitivity. The pD(2) value in rank order is as follows: WT mice (8.21) > alpha(1B)-adrenoceptor knockout (alpha(1B)-KO) (7.77) > alpha(1D)-AR knockout (alpha(1D)-KO) (6.44) > alpha(1B)- and alpha(1D)-AR double knockout (alpha(1BD)-KO) (5.15). In the mesenteric artery, CRCs for NAd did not differ significantly between either WT (6.52) and alpha(1B)-KO mice (7.12) or alpha(1D)-KO (6.19) and alpha(1BD)-KO (6.29) mice. However, the CRC maximum responses to NAd in alpha(1D)- and alpha(1BD)-KO mice were significantly lower than those in WT and alpha(1B)-KO mice. Except in the thoracic aortas of alpha(1BD)-KO mice, the competitive antagonist prazosin inhibited the contraction response to NAd with high affinity. However, prazosin produced shallow Schild slopes in the vessels of mice lacking the alpha(1D)-AR gene. In the thoracic aorta, pA(2) values in WT mice for KMD-3213 and BMY7378 were 8.25 and 8.46, respectively, and in alpha(1B)-KO mice they were 8.49 and 9.13, respectively. In the mesenteric artery, pA(2) values in WT mice for KMD-3213 and BMY7378 were 8.34 and 7.47, respectively, and in alpha(1B)-KO mice they were 8.11 and 7.82, respectively. These pharmacological findings were in fairly good agreement with findings from comparison of CRCs, with the exception of the mesenteric arteries of WT and alpha(1B)-KO mice, which showed low affinities to BMY7378. We performed a quantitative analysis of the mRNA expression of each alpha(1)-AR subtype in these vessels in order to examine the correlation between mRNA expression level and the predominance of each alpha(1)-AR subtype in mediating vascular contraction. The rank order of each alpha(1)-AR subtype in terms of its vasoconstrictor role was in fairly good agreement with the level of expression of mRNA of each subtype, that is, alpha(1D)-AR > alpha(1B)-AR > alpha(1A)-AR in the thoracic aorta and alpha(1D)-AR > alpha(1A)-AR > alpha(1B)-AR in the mesenteric artery. No dramatic compensatory change of alpha(1)-AR subtype in mutant mice was observed in pharmacological or quantitative mRNA expression analysis.

Deployment of self-expandable stents in aneurysmatic cerebral vessels: comparison of different computational approaches for interventional planning

In the last few years, there has been a growing focus on faster computational methods to support clinicians in planning stenting procedures. This study investigates the possibility of introducing computational approximations in modelling stent deployment in aneurysmatic cerebral vessels to achieve simulations compatible with the constraints of real clinical workflows. The release of a self-expandable stent in a simplified aneurysmatic vessel was modelled in four different initial positions. Six progressively simplified modelling approaches (based on Finite Element method and Fast Virtual Stenting – FVS) have been used. Comparing accuracy of the results, the final configuration of the stent is more affected by neglecting mechanical properties of materials (FVS) than by adopting 1D instead of 3D stent models. Nevertheless, the differencesshowed are acceptable compared to those achieved by considering different stent initial positions. Regarding computationalcosts, simulations involving 1D stent features are the only ones feasible in clinical context.

Ranibizumab in the management of advanced Coats disease Stages 3B and 4: long-term outcomes.

BACKGROUND: Laser photocoagulation and cryotherapy to completely destroy telangiectatic vessels and ischemic retina in Coats disease is barely applicable in advanced cases with total retinal detachment, and globe survival is notoriously poor in Stages 3B and 4. Anti-vascular endothelial growth factor intravitreal injections may offer new prospects for these patients. METHODS: This study is a retrospective review of all consecutive patients with Coats disease treated with neoadjuvant or adjuvant intravitreal ranibizumab plus conventional and amblyopia treatment as appropriate. RESULTS: Nine patients (median age, 13 months) presenting Coats Stages 3B and 4 (5 and 4 eyes, respectively) were included. Iris neovascularization resolved within 2 weeks and retinal reapplication within 4 months in all patients. At last follow-up, globe survival was 100% with anatomical success in 8 of the 9 eyes. With a median follow-up of 50 months, fibrotic vitreoretinopathy was developed in 5 of the 9 cases, one leading to tractional retinal detachment and ultimately phthisis bulbi. The remaining 4 of the 9 eyes achieved some vision (range, 0.02-0.063). CONCLUSION: To the best of the authors' knowledge, this is the largest reported series of late-stage Coats undergoing anti-vascular endothelial growth factor therapy, a homogenous cohort of patients treated with a single agent and with the longest follow-up. This study supports the role of ranibizumab in advanced disease by transient restoration of the hemato-retinal barrier and suppression of neovascularization to facilitate classic treatment. At the last follow-up, the authors report unprecedented anatomical success and functional outcome.

The sign of the Cross of Andreas in the iris and Diabetes Mellitus: a longitudinal study

OBJECTIVETo compare the development of diabetes mellitus in subjects with and without the sign of the Cross of Andreas in the iris over a period of four years.METHODA prospective, descriptive study of quantitative approach. This cohort study had 91 patients without the disease, with and without the signal. The monitoring was conducted by means of the records in medical charts.RESULTSAt the end of the research, 28.2% of the group with the sign of the Cross of Andreas was diagnosed with diabetes and 56.5% had two or more episodes of impaired glucose tolerance. In the group without the sign, 4.4% was diagnosed with the disease and 24.5% had two or more episodes of glucose intolerance. There was a statistically significant difference between the groups regarding the development of the disease and glucose intolerance.CONCLUSIONThe group with the Cross of Andreas developed more glucose intolerance and diabetes than the group without the sign.