1. Preparazione della placenta <ol><li> La placenta deve essere acquisita dalla sala parto il più presto possibile dopo il parto per ridurre al minimo la formazione di coaguli, essiccazione e generale deterioramento del tessuto. </li><li> Si deve prestare attenzione per assicurare che la placenta non sia esposto a fissativi formalina o altro. </li><li> Standard BSL2 precauzioni per tessuti umani devono essere mantenuti e il personale deve indossare una mascherina, camice, guanti e copriscarpe. </li><li> Posizionare la placenta in un plastico di grandi dimensioni o ciotola di metallo con fori pretagliati per consentire il drenaggio del liquido. Questa coppa deve essere collocato all&#39;interno di una ciotola più grande in acciaio inossidabile per evitare la fuoriuscita. </li><li> Lavare la placenta con soluzione salina calda. </li><li> Per una migliore visualizzazione della placenta, usare le forbici Metzenbaum ad accisa le membrane amniotiche fra i gemelli avendo cura di non danneggiare la placenta stessa. Lascia un bracciale ½ cm di inter-doppia membrana in posizione. (Figura 1A). </li></ol> 2. Cateterismo dei vasi placentari <ol><li> Identificare le corde dei gemelli rispettivi proprietari. Le ostetriche solitamente identificano ciascun gemello per il numero di fascette poste su ogni cavo. Assicurati di confermare che il cavo in dotazione presenta doppia (doppia A). </li><li> Uno alla volta, tenere traccia di quali cavo è che, ogni transetto cavo appena sotto i morsetti (Figura 1B). Coagulo di latte delicatamente fuori dai vasi (Figura 1C). Ai margini taglio del cordone ci sarà una vena e almeno uno, di solito due, arterie. Arterie sono identificati dal loro diametro relativamente piccolo (rispetto alla vena) e dintorni bracciale muscolare (Figura 1D). </li><li> Utilizzare uno standard radiale arteriosa filo guida di linea, 0,46 mm di diametro e 80 cm di lunghezza (Arrow, Reading PA, USA), con una punta morbida per accedere a un orifizio arteriosa sul bordo tagliato di gemelli cavo A (Figura 1E). </li><li> Il filo guida deve essere collocato un minimo di 3 cm in vaso. Gentle tensione contatore sulla porzione non vascolari del bordo taglio del cordone utilizzando una pinza di Kelly facilita notevolmente l&#39;avanzamento del filo. Svolta minori del cavo per raddrizzare i vasi tortuosi può aiutare con l&#39;avanzamento del filo. Si deve prestare attenzione per evitare passaggi false. </li><li> Utilizzando la tecnica di Seldinger, infilare un lungo 20 centimetri 0,6-1,19 millimetri di diametro interno catetere in polietilene (Intramedic, Batavia, IL, USA) con un finale senza mezzi termini smussato distale attraverso il cavo in arteria (Figura 1F). Bisogna fare attenzione a non spostare il filo contempo portare avanti il ​​catetere. Rimuovere il filo dopo catetere è seduto almeno 3 cm in vaso. </li><li> In alternativa, alcuni gruppi hanno avuto un successo senza l&#39;uso di un filo guida e incannulazione diretta dei vasi ombelicali con catetere arteria ombelicale. Anche se, questa tecnica funziona bene nelle nostre mani l&#39;uso di un filo guida è diminuito il tempo che ci porta a completare la procedura. </li><li> Collegare un G 18 smussato punta dell&#39;ago (BD Biosciences, Franlik Lakes, NJ, USA) per l&#39;estremità prossimale del tubo. Garantire il corretto posizionamento del catetere iniettando una piccola quantità di soluzione fisiologica nel vaso e osservando compensazione delle arterie distali. Spazza dito dolce a bordo delle navi, mentre l&#39;iniezione di soluzione salina può aiutare a facilitare il movimento di eventuali grumi residui. </li><li> Con attenzione ripetere i passaggi 2,3-2,6 per la vena di A doppia con attenzione per evitare di spostare il catetere arterioso. </li><li> Legare un pezzo di cordone ombelicale nastro 1 cm distalmente al bordo tagliare il cordone intorno e cateteri. Assicurare una buona tenuta per evitare il riflusso. </li><li> Ripetere il passo 2,3-2,9 per il cavo di gemelli B (la non-presentazione di singoli) in modo tale che ci sono cateteri in arteria ombelicale e la vena di ciascun gemello fissato con nastro ombelicale e due circolazioni sono stato infuso con soluzione fisiologica (Figura 2). </li></ol> 3. L&#39;iniezione di colorante nei vasi placentari <ol><li> Patologia colorante, sospensioni di bario, gelatina o altri coloranti viscoso di colore può essere utilizzato per visualizzare la vascolarizzazione placentare. Scegliere quattro colori contrastanti con cui iniettare le arterie e le vene dei gemelli A e B. I colori per l&#39;arteria e vena per ciascun gemello deve essere facilmente riconoscibile. Anastomosi superficiali dovrebbero essere rilevabili mescolando colorante e la formazione di una diversa (blended) colore facilmente riconoscibile. </li><li> Utilizzare una siringa da 3 ml a portata di mano iniettare l&#39;arteria di doppia A con tintura a bassa pressione. Delicatamente spazzare con una o due dita lungo i vasi nella direzione del flusso di tintura per assicurare il riempimento dell&#39;intero albero vascolare. Se un anastomosi vascolari superficiali è identificato, manuale occlusione del vaso di alimentazione possono essere impiegati per permettere il resto del letto maggiore resistenza vascolare per riempire (Figura 3A). </li><li> Utilizzare siringhe da 3 ml a portata di mano iniettare l&#39;arteria di gemelli B (Figura 3B). </li><li> Ripetere i passi 3.2 e 3.3 per le iniezioni venose. </li><li> In caso di perdite da un colorante ferito nave, la riparazione deve essere effettuata con una sutura sottile e un driver ago. Fare attenzione a non legare la sutura vess tuttoel. </li><li> Utilizzando una fotocamera ad alta risoluzione digitale, scattare una foto dopo ogni iniezione. Dopo tutto le iniezioni sono completi, rimuovere il campione dal bocce, posto su uno sfondo di colore neutro e ri-immagine (Figura 4). Documentare il numero e il tipo di connessioni tra circolazioni visto i gemelli &#39;. </li></ol> 4. Rappresentante dei risultati: Arteria di anastomosi arteria (AA) hanno dimostrato di essere &quot;protettivo&quot;, come sono associati a un rischio significativo di riduzione TTTS e con migliori risultati per entrambi i gemelli 5. Figura 4 dimostra un iniettato MC placenta singoli. Un AA era stato identificato da prospetticamente in utero ecografia Doppler. Questa scoperta è stata confermata dalla miscelazione di doppia A arteriosa (giallo) e doppia B arteriosa (blu) colorante in una struttura di comunicazione arteriosa (verde, freccia). Una anastomosi AV con arteria da doppia A (giallo) e la vena da doppia B (arancione) è anche dimostrato (testa di freccia). Figura 5 e 6 rappresentano le fotografie di due altri campioni placentare abbiamo iniettato. <img src="/files/ftp_upload/2837/2837fig1.jpg" alt="Figura 1"/> Figura 1. (A) La membrana amniotica viene accuratamente rimosso dalla superficie fetale della placenta MC condiviso con le forbici Metzenbaum. (B) Un lato pulito del cordone ombelicale del gemello A è esposto da resezione prossimale con le forbici Metzenbaum. (C) Clot è munto dal midollo dalla compressione manuale. (D) Le arterie ombelicali (punte di freccia) e la vena (freccia) del gemello A sono identificati. (E) Dopo il posizionamento di una pinza di Kelly sulla porzione avascolare della superficie di taglio del cordone per la trazione, un filo guida viene inserito nell&#39;arteria ombelicale dei gemelli A e delicatamente avanzata attraverso il vaso tortuoso. (F) Un piccolo catetere viene fatto avanzare il filo guida nel lume del vaso con la tecnica Seldinger. <img src="/files/ftp_upload/2837/2837fig2.jpg" alt="Figura 2"/> Cateteri Figura 2. Sono state collocate in un&#39;arteria ombelicale e nella vena ombelicale di ciascun gemello. Questi cateteri sono fissate in posizione con legami ombelicali nastro intorno al midollo intero. Il corretto posizionamento di ogni catetere è stato confermato e coaguli intraluminale sono stati liquidati con l&#39;iniezione di soluzione salina riscaldata. <img src="/files/ftp_upload/2837/2837fig3.jpg" alt="Figura 3"/> Figura 3. (A) La circolazione arteriosa del gemello A viene iniettato con colorante giallo. Contrasto passa chiaramente attraverso l&#39;equatore vascolare arteriosa nella circolazione dei gemelli B. (B) La circolazione arteriosa di B gemello viene iniettato con colorante blu. Mescolando il colorante giallo e blu della colorazione in tinta verde all&#39;interno della AA ha dimostrato anastomosi (freccia). <img src="/files/ftp_upload/2837/2837fig4.jpg" alt="Figura 4"/> Figura 4. La vena di doppia A (rosso) e la vena di gemelli B (arancione) sono stati iniettati. L&#39;anastomosi AA (freccia) e un anastomosi AV, con flusso diretto dalla A matrimoniali verso gemello B, (punta di freccia) sono delineati. <img src="/files/ftp_upload/2837/2837fig5.jpg" alt="Figura 5"/> Figura 5. Esempio di MC gemelli placenta che ha subito la terapia laser dopo l&#39;iniezione postnatale. Arteria Il gemello donatore e vena sono rispettivamente giallo e verde. L&#39;arteria e la vena del destinatario sono in blu e arancio, rispettivamente. Nessun collegamento residua tra la circolazione sono stati rilevati. <img src="/files/ftp_upload/2837/2837fig6.jpg" alt="Figura 6"/> Figura 6. Esempio di MC gemelli placenta dopo l&#39;iniezione. Arteria Il gemello lato sinistro e vena sono in giallo e rosso rispettivamente. L&#39;arteria del lato destro e vena gemelli sono in blu e arancio, rispettivamente. Un AA (punta di freccia) e VV (freccia) sono visibili sulla superficie della placenta.

<ol>
	<li>Rand, L., Lee, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Complicated+monochorionic+twin+pregnancies:+updates+in+fetal+diagnosis+and+treatment.">Complicated monochorionic twin pregnancies: updates in fetal diagnosis and treatment.</a> Clin Perinatol. 36, 417-430 (2009).</li><li>Sebire, N., Talbert, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Twin-to-twin+transfusion+syndrome+results+from+dynamic+asymmetrical+reduction+in+placental+anastomoses:+a+hypothesis.">Twin-to-twin transfusion syndrome results from dynamic asymmetrical reduction in placental anastomoses: a hypothesis.</a> in Placenta. , (2001).</li><li>Machin, G. A., Keith, L. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> An atlas of multiple pregnancy: biology and pathology. , (1999).</li><li>Machin, G. A., Feldstein, V. A., van Gemert, M. J., Keith, L. G., Hecher, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Doppler+sonographic+demonstration+of+arterio-venous+anastomosis+in+monochorionic+twin+gestation.">Doppler sonographic demonstration of arterio-venous anastomosis in monochorionic twin gestation.</a> Ultrasound Obstet Gynecol. 16, 214-217 (2000).</li><li>Denbow, M. L., Cox, P., Taylor, M., Hammal, D. M., Fisk, N. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Placental+angioarchitecture+in+monochorionic+twin+pregnancies:+Relationship+to+fetal+growth,+fetofetal+transfusion+syndrome,+and+pregnancy+outcome.">Placental angioarchitecture in monochorionic twin pregnancies: Relationship to fetal growth, fetofetal transfusion syndrome, and pregnancy outcome.</a> American Journal of Obstetrics and Gynecology. 182, 417-426 (2000).</li><li>Taylor, M. J. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Doppler+detection+of+arterio-arterial+anastomoses+in+monochorionic+twins:+feasibility+and+clinical+application.">Doppler detection of arterio-arterial anastomoses in monochorionic twins: feasibility and clinical application.</a> Human Reproduction. 15, 1632-1636 (2000).</li><li>Berm&#250;dez, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Placental+types+and+twin-twin+transfusion+syndrome.">Placental types and twin-twin transfusion syndrome.</a> American Journal of Obstetrics and Gynecology. 187, 489-494 (2002).</li><li>Lewi, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intertwin+anastomoses+in+monochorionic+placentas+after+fetoscopic+laser+coagulation+for+twin-to-twin+transfusion+syndrome:+is+there+more+than+meets+the+eye.">Intertwin anastomoses in monochorionic placentas after fetoscopic laser coagulation for twin-to-twin transfusion syndrome: is there more than meets the eye.</a> Am J Obstet Gynecol. 194, 790-795 (2006).</li><li>Wee, L. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterisation+of+deep+arterio-venous+anastomoses+within+monochorionic+placentae+by+vascular+casting.">Characterisation of deep arterio-venous anastomoses within monochorionic placentae by vascular casting.</a> Placenta. 26, 19-24 (2005).</li><li>Paepe, M. E. D. e., Burke, S., Luks, F. I., Pinar, H., Singer, D. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Demonstration+of+placental+vascular+anatomy+in+monochorionic+twin+gestations.">Demonstration of placental vascular anatomy in monochorionic twin gestations.</a> Pediatr Dev Pathol. 5, 37-44 (2002).</li></ol>

Nessun conflitto di interessi dichiarati.

Mappatura vascolare di placente MC doppia per iniezione colorante è una procedura utile per la valutazione complessa, casi clinici trattati e per valorizzare ulteriormente la nostra comprensione del gemellaggio MC. Coordinamento con il team ostetrico per assicurare l&#39;acquisizione rapida di un esemplare integro placentare è cruciale. Essiccazione o conservazione prolungata del tessuto prima dell&#39;iniezione può portare a lesioni nave e stravaso di colorante. Fissazione della placenta devono essere evitati, perch...

<table border="1"><tbody><tr><th> Nome del reagente </th><th> Azienda </th><th> Numero di catalogo </th><th> Commenti (opzionale) </th></tr><tr><td> Ciotola di plastica perforata </td><td> QuickMedical attrezzature mediche e forniture </td><td> Polarware PA75 </td><td> Perforazioni possono essere effettuati con un trapano </td></tr><tr><td> Vasca in acciaio inox </td><td> Narang Medical Limited </td><td> HH517 </td><td></td></tr><tr><td> Saline normale </td><td> Pescatore </td><td> 50983204 </td><td></td></tr><tr><td> 0,6-1,9 mm ID tubi in polietilene </td><td> Intramedic </td><td> 7436 </td><td></td></tr><tr><td> Arterioso filo guida linea (0,46 mm) </td><td> Arrow International </td><td> PW-18080 </td><td> Punta morbida </td></tr><tr><td> 18 G Blunt Needles </td><td> BD Biosciences </td><td> 305180 </td><td></td></tr><tr><td> Ombelicale Tape </td><td> QC fornitura </td><td> 140895 </td><td></td></tr><tr><td> Metzenbaum forbici </td><td> Cole-Parmer </td><td> EW-10921-04 </td><td></td></tr><tr><td> Kelly morsetto </td><td> Cole Parmer </td><td> EW-10918-20 </td><td></td></tr><tr><td> 3 ml siringa </td><td> Covidien </td><td> 1180300555 </td><td></td></tr><tr><td> Patologia Dye </td><td> Bradley </td><td> 7365-x </td><td></td></tr><tr><td> Macchina fotografica digitale </td><td> Panasonic </td><td> Lumix TZ50- </td><td></td></tr></tbody></table>

guide wire assisted catheterization and colored dye injection for vascular mapping of monochorionic twin placentas

Monocoriali (MC) gravidanze gemellari sono associate a morbilità significativamente più alti e tassi di mortalità rispetto gemelli dicoriali. Circa il 50% delle gravidanze MC gemelli sviluppare complicanze derivanti dalla condivisione placenta e connessioni vascolari associate 1. Gravi gemello-gemello sindrome (TTTS) è segnalato per conto di circa il 20% di queste complicanze 2,3. Connessioni vascolari tra gemelli si verificano in quasi tutte le placente MC e sono relativi alla prognosi e l&#39;esito di queste gravidanze gemellari ad alto rischio. Il numero, le dimensioni e il tipo di collegamenti sono stati implicati nello sviluppo di TTTS e di altre condizioni MC singoli. Tre tipi di connessioni vascolari fra i gemelli si verificano: 1) arteria di collegamento vena (AVS) in cui un ramo di un&#39;arteria che porta sangue deossigenato da una doppia corsi lungo la superficie fetale della placenta e si tuffa in un cotiledone placentare. Sangue scorre attraverso una profonda intraparenchimale rete capillare in una vena drenante che emerge in superficie fetale della placenta e porta il sangue ossigenato verso l&#39;altro gemello. C&#39;è flusso unidirezionale dal gemello fornire l&#39;arteria afferente verso il gemello riceve la vena efferente; 2) arteria di collegamento dell&#39;arteria (AA) in cui un ramo dell&#39;arteria da ciascun gemello risponde direttamente sulla superficie della placenta con conseguente superficiale in un vaso con pulsatile bidirezionale flusso, e 3) vena di connessioni vena (VV) in cui una vena ramo di ogni gemelli risponde direttamente sulla superficie placentare superficiale a bassa pressione che permette il flusso bidirezionale. In utero con ecografia ostetrica mirati interrogatori Doppler è stato utilizzato per identificare la presenza di AV e le connessioni AA 4. AA rilevato prima della nascita che sono stati confermati da studi post-natale iniezione placentare hanno dimostrato di essere associato ad un miglioramento della prognosi per entrambi i gemelli 5. Inoltre, l&#39;ablazione laser fetoscopic delle connessioni vascolari tra gemelli sulla superficie fetale della placenta condivisa è ora il trattamento preferito per i primi, TTTS grave. Postnatale studi iniezione placentare fornire un metodo valido per confermare l&#39;accuratezza delle prenatale ecografia Doppler e l&#39;efficacia della terapia laser fetale 6. Utilizzando tinture colorate a mano separatamente iniettato nella circolazione arteriosa e venosa di ciascun gemello, mette in evidenza la tecnica e delinea AVS, AA e VV. Questa dimostrazione definitiva di anatomia vascolare MC placentare può quindi essere correlata con i risultati Doppler e l&#39;esito neonatale per migliorare la nostra comprensione della patofisiologia del gemellaggio MC e delle sue sequele. Qui mostriamo la nostra tecnica di iniezione placentare.

Watch this Scientific Journal Video about Guide Wire Assisted Catheterization and Colored Dye Injection for Vascular Mapping of Monochorionic Twin Placentas at JoVE.com

Guide Wire Assisted Catheterization and Colored Dye Injection for Vascular Mapping of Monochorionic Twin Placentas

Mappatura vascolare di monocoriali (MC) placente gemelli dopo la nascita fornisce un mezzo per la dimostrazione dettagliata delle connessioni vascolari tra i gemelli circolazione &#39;. Squilibrio di queste connessioni è pensato per svolgere un ruolo centrale nello sviluppo delle complicanze del gemellaggio tra MC gemello-gemello sindrome di trasfusione.

Guida cateterizzazione filo assistita e colorate iniezione Colorante per la mappatura vascolare di placente monocoriali Gemelle

Monochorionic (MC) twin pregnancies are associated with significantly higher morbidity and mortality rates than dichorionic twins. Approximately 50% of MC ...

guide-wire-assisted-catheterization-colored-dye-injection-for

Research

JoVE Journal

Medicine

14.8K Views.  University of California, San Francisco. Mappatura vascolare di monocoriali (MC) placente gemelli dopo la nascita fornisce un mezzo per la dimostrazione dettagliata delle connessioni vascolari tra i gemelli circolazione '. Squilibrio di queste connessioni è pensato per svolgere un ruolo centrale nello sviluppo delle complicanze del gemellaggio tra MC gemello-gemello sindrome di trasfusione.

Video: Guide Wire Assisted Catheterization and Colored Dye Injection for Vascular Mapping of Monochorionic Twin Placentas

Basic Surgical Techniques in the G&ouml;ttingen Minipig: Intubation, Bladder Catheterization, Femoral Vessel Catheterization, and Transcardial Perfusion

The emergence of the G&ouml;ttingen minipig in research of topics such as neuroscience, toxicology, diabetes, obesity, and experimental surgery reflects the close resemblance of these animals to human anatomy and physiology 1-6.The size of the G&ouml;ttingen minipig permits the use of surgical equipment and advanced imaging modalities similar to those used in humans 6-8. The aim of this instructional video is to increase the awareness on the value of minipigs in biomedical research, by demonstrating how to perform tracheal intubation, transurethral bladder catheterization, femoral artery and vein catheterization, as well as transcardial perfusion. 
Endotracheal Intubation should be performed whenever a minipig undergoes general anesthesia, because it maintains a patent airway, permits assisted ventilation and protects the airways from aspirates. Transurethral bladder catheterization can provide useful information about about hydration state as well as renal and cardiovascular function during long surgical procedures. Furthermore, urinary catheterization can prevent contamination of delicate medico-technical equipment and painful bladder extension which may harm the animal and unnecessarily influence the experiment due to increased vagal tone and altered physiological parameters. Arterial and venous catheterization is useful for obtaining repeated blood samples and monitoring various physiological parameters. Catheterization of femoral vessels is preferable to catheterization of the neck vessels for ease of access, when performing experiments involving frame-based stereotaxic neurosurgery and brain imaging. When performing vessel catheterization in survival studies, strict aseptic technique must be employed to avoid infections6. Transcardial perfusion is the most effective fixation method, and yields preeminent results when preparing minipig organs for histology and histochemistry2,9. For more information about anesthesia, surgery and experimental techniques in swine in general we refer to Swindle 2007. Supplementary information about premedication and induction of anesthesia, assisted ventilation, analgesia, pre- and postoperative care of G&ouml;ttingen minipigs are available via the internet at <a href="http://www.minipigs.com">http://www.minipigs.com</a>10. For extensive information about porcine anatomy we refer to Nickel et al. Vol. 1-511.

Basic Surgical Techniques in the G&amp;#246;ttingen Minipig: Intubation, Bladder Catheterization, Femoral Vessel Catheterization, and Transcardial Perfusion

The use of domestic and miniature pigs in science has increased significantly in recent years. By demonstrating how to perform intubation, transurethral bladder catheterization, femoral artery and vein catheterization, as well as transcardial perfusion, we aim to further increase the value of G&ouml;ttingen minipigs in biomedical research.

Tecniche chirurgiche di base Nella cavia Gottinga: intubazione, cateterismo vescicale, cateterizzazione nave femorale, e Perfusione Transcardial

The emergence of the G&ouml;ttingen minipig in research of topics such as neuroscience, toxicology, diabetes, obesity, and experimental surgery reflects ...

Ricerca

Medicina

Mesenteric Artery Contraction and Relaxation Studies Using Automated Wire Myography

Proximal resistance vessels, such as the mesenteric arteries, contribute substantially to the peripheral resistance. These small vessels of between 100-400 &mu;m in diameter function primarily in directing blood flow to various organs according to the overall requirements of the body. The rat mesenteric artery has a diameter greater than 100 &mu;m. The myography technique, first described by Mulvay and Halpern1, was based on the method proposed by Bevan and Osher2. The technique provides information about small vessels under isometric conditions, where substantial shortening of the muscle preparation is prevented. Since force production and sensitivity of vessels to different agonists is dependent on the extent of stretch, according to active tension-length relation, it is essential to conduct contraction studies under isometric conditions to prevent compliance of the mounting wires. Stainless steel wires are preferred to tungsten wires because of oxidation of the latter, which affects recorded responses3.The technique allows for the comparison of agonist-induced contractions of mounted vessels to obtain evidence for normal function of vascular smooth muscle cell receptors.
We have shown in several studies that isolated mesenteric arteries that are contracted with phenylyephrine relax upon addition of cumulative concentrations of extracellular calcium (Ca2+e). The findings led us to conclude that perivascular sensory nerves, which express the G protein-coupled Ca2+-sensing receptor (CaR), mediate this vasorelaxation response. Using an automated wire myography method, we show here that mesenteric arteries from Wistar, Dahl salt-sensitive(DS) and Dahl salt-resistant (DR) rats respond differently to Ca2+e. Tissues from Wistar rats showed higher Ca2+-sensitivity compared to those from DR and DS. Reduced CaR expression in mesenteric arteries from DS rats correlates with reduced Ca2+e-induced relaxation of isolated, pre-contracted arteries. The data suggest that the CaR is required for relaxation of mesenteric arteries under increased adrenergic tone, as occurs in hypertension, and indicate an inherent defect in the CaR signaling pathway in Dahl animals, which is much more severe in DS.
The method is useful in determining vascular reactivity ex vivo in mesenteric resistance arteries and similar small blood vessels and comparisons between different agonists and/or antagonists can be easily and consistently assessed side-by-side6,7,8.

An automated myography method for force measurements in isolated mesenteric arteries is described. It employs a Mulvany-Halpern Auto Dual Wire Myograph 510A to determine responses to phenylephrine and extracellular calcium. The method allows consistent determination of isometric responses to agonists in small vessels of diameters of 60 - 300 &mu;m, independently.

Contrazione Arteria mesenterica e Studi Relax Utilizzando Myography automatica Wire

Proximal resistance vessels, such as the mesenteric arteries, contribute substantially to the peripheral resistance. These small vessels of between ...

Accurate and Simple Evaluation of Vascular Anastomoses in Monochorionic Placenta using Colored Dye

The presence of placental vascular anastomoses is a conditio sine qua non for the development of twin-to-twin transfusion syndrome (TTTS) and twin anemia polycythemia sequence (TAPS)1,2. Injection studies of twin placentas have shown that such anastomoses are almost invariably present in monochorionic twins and extremely rare in dichorionic twins1. Three types of anastomoses have been documented: from artery to artery, from vein to vein and from artery to vein. Arterio-venous (AV) anastomoses are unidirectional and are referred to as "deep" anastomoses since they proceed through a shared placental cotyledon, whereas arterio-arterial (AA) and veno-venous (VV) anastomoses are bi-directional and are referred to as "superficial" since they lie on the chorionic plate. Both TTTS and TAPS are caused by net imbalance of blood flow between the twins due to AV anastomoses. Blood from one twin (the donor) is pumped through an artery into the shared placental cotyledon and then drained through a vein into the circulation of the other twin (the recipient). Unless blood is pumped back from the recipient to the donor through oppositely directed deep AV anastomoses or through superficial anastomoses, an imbalance of blood volumes occurs, gradually leading to the development of TTTS or TAPS. The presence of an AA anastomosis has been shown to protect against the development of TTTS and TAPS by compensating for the circulatory imbalance caused by the uni-directional AV anastomoses1,2. 
Injection of monochorionic placentas soon after birth is a useful mean to understand the etiology of various (hematological) complications in monochorionic twins and is a required test to reach the diagnosis of TAPS2. In addition, injection of TTTS placentas treated with fetoscopic laser surgery allows identification of possible residual anastomoses3-5. This additional information is of paramount importance for all perinatologists involved in the management and care of monochorionic twins with TTTS or TAPS. Several placental injection techniques are currently being used. We provide a simple protocol to accurately evaluate the presence of (residual) vascular anastomoses using colored dye injection.

Twin-to-twin transfusion syndrome and twin anemia polycythemia sequence are two potentially devastating problems in perinatal medicine. Both disorders occur only in monochorionic twins and result from unbalanced blood flow through placental vascular anastomoses. We provide a simple protocol to accurately evaluate the presence of vascular anastomoses using colored dye injection of placental vessels after birth.

La valutazione accurata e semplice delle anastomosi vascolari in placenta monocoriale con colorante

The presence of placental vascular anastomoses is a conditio sine qua non for the development of twin-to-twin transfusion syndrome (TTTS) and twin anemia ...

Accuracy in Dental Medicine, A New Way to Measure Trueness and Precision

Reference scanners are used in dental medicine to verify a lot of procedures. The main interest is to verify impression methods as they serve as a base for dental restorations. The current limitation of many reference scanners is the lack of accuracy scanning large objects like full dental arches, or the limited possibility to assess detailed tooth surfaces. A new reference scanner, based on focus variation scanning technique, was evaluated with regards to highest local and general accuracy. A specific scanning protocol was tested to scan original tooth surface from dental impressions. Also, different model materials were verified. The results showed a high scanning accuracy of the reference scanner with a mean deviation of 5.3 &#177; 1.1 &#181;m for trueness and 1.6 &#177; 0.6 &#181;m for precision in case of full arch scans. Current dental impression methods showed much higher deviations (trueness: 20.4 &#177; 2.2 &#181;m, precision: 12.5 &#177; 2.5 &#181;m) than the internal scanning accuracy of the reference scanner. Smaller objects like single tooth surface can be scanned with an even higher accuracy, enabling the system to assess erosive and abrasive tooth surface loss. The reference scanner can be used to measure differences for a lot of dental research fields. The different magnification levels combined with a high local and general accuracy can be used to assess changes of single teeth or restorations up to full arch changes.

Accuracy is a major demand in dental medicine. To verify accuracy, reference scanners are needed. This article presents a new reference scanner with an adjusted scanning method to acquire a broad variety of dental morphologies with high trueness and precision.

Accuratezza nella Dental Medicine, Un nuovo modo di misurare veridicità e precisione

Reference scanners are used in dental medicine to verify a lot of procedures. The main interest is to verify impression methods as they serve as a base ...

A Murine Model of Arterial Restenosis: Technical Aspects of Femoral Wire Injury

Cardiovascular disease caused by atherosclerosis is the leading cause of death in the developed world. Narrowing of the vessel lumen, due to atherosclerotic plaque development or the rupturing of established plaques, interrupts normal blood flow leading to various morbidities such as myocardial infarction and stroke. In the clinic endovascular procedures such as angioplasty are commonly performed to reopen the lumen. However, these treatments inevitably damage the vessel wall as well as the vascular endothelium, triggering an excessive healing response and the development of a neointimal plaque that extends into the lumen causing vessel restenosis (re-narrowing). Restenosis remains a major cause of failure of endovascular treatments for atherosclerosis. Thus, preclinical animal models of restenosis are vitally important for investigating the pathophysiological mechanisms as well as translational approaches to vascular interventions. Among several murine experimental models, femoral artery wire injury is widely accepted as the most suitable for studies of post-angioplasty restenosis because it closely resembles the angioplasty procedure that injures both endothelium and vessel wall. However, many researchers have difficulty utilizing this model due to its high degree of technical difficulty. This is primarily because a metal wire needs to be inserted into the femoral artery, which is approximately three times thinner than the wire, to generate sufficient injury to induce prominent neointima. Here, we describe the essential surgical details to effectively overcome the major technical difficulties of this model. By following the presented procedures, performing the mouse femoral artery wire injury becomes easier. Once familiarized, the whole procedure can be completed within 20 min.

The mouse femoral artery wire injury model of restenosis is technically challenging. In this protocol we show the key technical details essential for successfully performing wire injury to induce consistent&#160;neointima for studies of restenosis.

Un modello murino di restenosi arteriosa: aspetti tecnici del femore Wire Injury

Cardiovascular disease caused by atherosclerosis is the leading cause of death in the developed world. Narrowing of the vessel lumen, due to ...

Induction of Accelerated Atherosclerosis in Mice: The "Wire-Injury" Model

Atherosclerosis is a proliferative fibro-inflammatory disease developing in the arterial wall, inducing a deficient blood flow or a lack of blood flow. Moreover, by rupture of the defective vascular wall, atherosclerosis induces occlusive thrombus formation, which represents the main cause of myocardial infarction or stroke and the most frequent cause of death. Despite the advances in the cardiovascular field, many questions remain unanswered, and additional basic research is essential to improve our understanding of the molecular mechanisms during atherosclerosis and its effects. Due to limited clinical studies, there is a need for representative animal models recreating atherosclerotic conditions such as neointima formation after stent implantation, balloon angioplasty, or endarterectomy. Since the mouse presents many advantages and is the most frequently used model for studying molecular processes, the current study proposes an invasive procedure of endothelial denudation, also known as the wire-injury model, which is representative of the human condition of neointima formation in arteries after revascularization procedures.

Induction of Accelerated Atherosclerosis in Mice: The &quot;Wire-Injury&quot; Model

This study describes an invasive procedure for the induction of accelerated atherosclerosis in mice. In comparison to other methods using electric- or cryo-induced injury, mechanical-induced injury mimics the human condition of restenosis after revascularization therapies and is ideal for the study of the molecular mechanisms involved.

Induzione di aterosclerosi accelerata nei topi: il modello "Wire-Injury"

Atherosclerosis is a proliferative fibro-inflammatory disease developing in the arterial wall, inducing a deficient blood flow or a lack of blood flow. ...

Shunt Surgery, Right Heart Catheterization, and Vascular Morphometry in a Rat Model for Flow-induced Pulmonary Arterial Hypertension

In this protocol, PAH is induced by combining a 60 mg/kg monocrotalin (MCT) injection with increased pulmonary blood flow through an aorto-caval shunt (MCT+Flow). The shunt is created by inserting an 18-G needle from the abdominal aorta into the adjacent caval vein. Increased pulmonary flow has been demonstrated as an essential trigger for a severe form of PAH with distinct phases of disease progression, characterized by early medial hypertrophy followed by neointimal lesions and the progressive occlusion of the small pulmonary vessels. To measure the right heart and pulmonary hemodynamics in this model, right heart catheterization is performed by inserting a rigid cannula containing a flexible ball-tip catheter via the right jugular vein into the right ventricle. The catheter is then advanced into the main and the more distal pulmonary arteries. The histopathology of the pulmonary vasculature is assessed qualitatively, by scoring the pre- and intra-acinar vessels on the degree of muscularization and the presence of a neointima, and quantitatively, by measuring the wall thickness, the wall-lumen ratios, and the occlusion score.

This protocol describes a surgical procedure to create a model for flow-induced pulmonary arterial hypertension (PAH) in rats and the procedures to analyze the principle hemodynamic and histological end-points in this model.

Chirurgia Shunt, Destra cuore cateterizzazione, e Vascolare Morfometria in un modello di ratto per Flow-indotta ipertensione arteriosa polmonare

In this protocol, PAH is induced by combining a 60 mg/kg monocrotalin (MCT) injection with increased pulmonary blood flow through an aorto-caval shunt ...

Model Surgical Training: Skills Acquisition in Fetoscopic Laser Photocoagulation of Monochorionic Diamniotic Twin Placenta Using Realistic Simulators

Fetoscopic laser coagulation of arterio-venous anastomoses (AVA) in a monochorionic placenta is the standard of care for twin-twin transfusion syndrome (TTTS), but is technically challenging and can lead to significant complications. Acquiring and maintaining the necessary surgical skills require consistent practice, a critical caseload, and time. Training on realistic surgical simulators can potentially shorten this steep learning curve and enables several proceduralists to acquire procedure-specific skills simultaneously. Here we describe realistic simulators designed to allow the user familiarity with the equipment and specific steps required in the surgical treatment of TTTS, including fetoscopic handling, approaches to anterior and posterior placenta, recognition of anastomoses, and efficient coagulation of vessels. We describe the skills that are especially important in conducting placental laser coagulation that the surgeon can practice on the model and apply in a clinical case. These models can be adapted easily depending on the availability of materials and require standard fetoscopy equipment. Such training systems are complementary to traditional surgical apprenticeships and can be useful aids for fetal medicine units that provide this clinical service.

Practicing the specific skills required for fetoscopic laser coagulation of monochorionic placental anastomoses on realistic models can aid less experienced surgeons in overcoming the steep learning curve associated with this procedure that is now regarded as the standard of care for twin-twin transfusion syndrome.

Modello di Training chirurgico: Acquisizione di competenze in photocoagulation del Laser Fetoscopic di Monochorionic Diamniotic Twin Placenta utilizzando simulatori realistici

Fetoscopic laser coagulation of arterio-venous anastomoses (AVA) in a monochorionic placenta is the standard of care for twin-twin transfusion syndrome ...

Induction of Nephrotic Syndrome in Mice by Retrobulbar Injection of Doxorubicin and Prevention of Volume Retention by Sustained Release Aprotinin

Nephrotic syndrome is the most extreme manifestation of proteinuric kidney disease and characterized by heavy proteinuria, hypoalbuminemia, and edema due to sodium retention and hyperlipidemia. To study the pathophysiology of this syndrome, rodent models have been developed based on the injection of toxic substances such as doxorubicin causing podocyte damage. In mice, only few strains are susceptible to this model. In wildtype 129S1/SvImJ mice, the administration of doxorubicin by rapid intravenous injection to the retrobulbar sinus induces experimental nephrotic syndrome that features all the symptoms of human disease including sodium retention and edema. After the onset of proteinuria, mice exhibit increased urinary serine protease activity that leads to the activation of the epithelial sodium channel (ENaC) and sodium retention. Pharmacological inhibition of urinary serine proteases by the treatment with sustained release aprotinin abrogates ENaC activation and prevents sodium retention. This model is ideal to study the pathophysiology of proteasuria, i.e., the excretion of active serine proteases that cause ENaC activation by the proteolysis of its &#947;-subunit. This can be regarded as the primary mechanism of ENaC activation and sodium retention in proteinuric kidney disease.

Here, we describe the induction of experimental nephrotic syndrome in 129S1/SvImJ mice by rapid retrobulbar injection of doxorubicin. We also treat nephrotic mice with sustained release pellets containing aprotinin to inhibit urinary serine protease activity and prevent sodium retention.

Induzione della sindrome nefrotica in topi da iniezione Retrobulbar di doxorubicina e prevenzione della ritenzione di Volume di rilascio prolungato aprotinina

Nephrotic syndrome is the most extreme manifestation of proteinuric kidney disease and characterized by heavy proteinuria, hypoalbuminemia, and edema due ...

Three-Dimensional Printing Guide Template Assisted Percutaneous Vertebroplasty (PVP)

Percutaneous vertebroplasty (PVP) is considered an effective treatment for the back pain caused by osteoporotic vertebral compression fracture. The accuracy of PVP mainly depends on the surgeons&#39; experience and multiple fluoroscopes during a traditional procedure. Puncture related complications were reported all over the world. To make the surgical procedure more precise and decrease the rate of puncture-related complications, our team applied a three-dimensional printing guide template to PVP to modify the traditional procedure. This protocol introduces how to model target vertebrae DICOM imaging data into three-dimensions in the software, how to simulate operation in this 3-D model, and how to use all of the surgical data to reconstruct a patient specific template for application. Using this template, surgeons can identify suitable puncture points accurately to improve the accuracy of the operation. The whole protocol includes: 1) diagnosis of the osteoporotic vertebral compression fracture; 2) acquisition of CT imaging of the target vertebra; 3) simulation of the operation in the software; 4) design and fabrication of the 3-D printing guide template; and 5) application of the template into an operation procedure.

Three-Dimensional Printing Guide Template Assisted Percutaneous Vertebroplasty PVP

Herein, we present a three-dimensional printing guide template for percutaneous vertebraplasty. A patient with a T11 vertebral compression fracture was selected as a case study.

Vertebroplastica percutanea percutanea percutanea (PVP)

Percutaneous vertebroplasty (PVP) is considered an effective treatment for the back pain caused by osteoporotic vertebral compression fracture. The ...