Biz Vevo 2100 ultrason sisteminin sağlanması için Hong Kong Politeknik Üniversitesi Yaşam Bilimleri (ULS) Üniversite Araştırma Tesisi kabul etmek istiyorum. eğitim ve kolaylaştırılması için Biyomedikal Mühendisliği, Hong Kong Polytechnic Üniversitesi, Disiplinlerarası Bölümü Dr. Chunyi Wen özel teşekkürler. Bu çalışma HK hükümeti RGC Grant GRF 17127215, 764812 ve Billy KC Chow HKU6 / CRF / 11g tarafından desteklenmiştir.

protokol Hong Kong Üniversitesi Eğitim ve Araştırma (CULATR) Canlı Hayvanların Kullanımı Komitesi kuralları takip eder. 1. Çalışma Sitesi Hazırlama <ol><li> % 75 izopropil alkol ile işlem sitesini dezenfekte edin. kalp değişiklikleri ve konu hayvanın solunum oranları önlemek için 37 ° C ısıtma yastığı sıcaklığını ayarlamak. </li><li> 30 dakika için ya da diğer uygun yöntemlerle, 121 ° C de bir ağırlık yer değiştirme sterilizatör sterilize cerrahi aletleri kullanarak. </li><li> Şekil 1&#39;de görüldüğü gibi ligasyon ve doku ayrılması ve bir retraktörü olarak kullanılmak üzere bir araç yapmak için, 4 30-gauge iğne ve bir iğne tutucu ile eğri onları - Take 2. cerrahide kullanılacak pamuklu bir aplikatör şimdi eğimli iğne monte edin. </li><li> o iğne tutucu ile 90º 27-gauge iğne ve eğri künt. ligasyon adımda bir 0,4 mm boşluk yapmak için sert bir yüzeye sürterek ucu pürüzsüz. </li></ol><ol><li> Negatif kuyruk tutam refleksi ile anestezi teyit 100 mg / kg + 10 mg / kg ip: vücut ağırlığı ile ilgili olarak uygun bir ketamin ve ksilazin karışımı 2 aylık, Erkek, 22-25 g C57BL / 6N fare anestezisi . </li><li> tüy dökücü krem ​​2- 3 dk uygulama ile ön boyun ve göğüs üzerinde saç çıkarın. ılık su ve pamuk aplikatör ile krem ​​çıkarın. </li><li> kornea kurumasını önlemek için bir hayvanın gözleri oftalmik merhem veya jel uygulanır. </li><li> Sırtüstü pozisyonda bir ısıtma pedi üzerinde hayvan koyun ve her 15 dakika aralıklarla uygun belgeleri tutmak için emin olmak, intra-operatif izleme yapmak. </li><li> Ameliyat sırasında doğru pozisyonda hayvan tutmak için ısıtma pedi ile bacaklarda güvenli cerrahi kağıt bant kullanın. </li><li> alkol ve povidon-iyot çözeltisi ile üç kez dönüşümlü olarak cildi dezenfekte edin. </li><li> steril bir dr kullanınBir açık işletme alanı ile maymun bulaşmasını önlemek için. Her fare ve gerektiğinde yeni steril eldiven kullanın. </li></ol> 3. Ligasyon Prosedür <ol><li> bir neşter ile boyun ve göğüs orta hat konumundaki fare cildi açın. </li><li> nazikçe künt makas ile bağ dokuları ayırarak kafasına doğru tiroid bezi çekin. </li><li> kavisli iğne ile her iki tarafta karşı orta hatta trakea kas tabakası ayırın. </li><li> künt makas kullanarak, ikinci kaburga (yaklaşık 5 mm) sternum kesti. Bir retraktör veya kavisli bir forseps ile kesim açın. </li><li> birbirlerine ve kavisli iğne ile bağ dokusu ayırarak alt göğüs duvarından timus lobları ayırın; enine aortik ark ve iki karotis arterler bu noktada açıkça görünür olacaktır. </li><li> kemer altında kavisli iğne yerleştirin ve irin ile diğer tarafta damar duvarı ve bağ dokusu arasında perforateeğimli kafa dışarı hing. </li><li> kavisli iğne kullanarak, aort kavsi altında 6-0 monofilament sütür çekin. </li><li> döngüde boşluk koyun ve bir çift düğüm ile bir yerde dikiş düzeltmek. nazikçe boşluk çıkarın. </li><li> düğüm pozisyonu ile başarılı bir daralma onaylamak ve sütür uçlarını kesin. </li><li> Basit bir kesintiye dikiş deseni ile 6/0 ipek sütür kullanılarak göğüs duvarı kapatın. Sürekli dikiş desen bir 6/0 monofilament sütür ile cilt kapatın. </li></ol> 4. Post-operatif Bakım <ol><li> dikiş sitesine povidon-iyot çözeltisi uygulayın ve kurtarma ve post-operatif izlenmesi için önceden ısıtılmış kafeste hayvan yerleştirin. </li><li> hayvan ağrıyı hafifletmek ve uygun yumuşak gıda ile fare sağlamak için kendine geldi sonra - (0.1 mg / kg sc 12 saatte 0.05) buprenorfin enjekte edilir. </li><li> tam iyileşme sonrası 12 saat aydınlık / karanlık döngüsü odasına hayvan dönün. </li></ol> 5.Ekokardiyografi: Başarılı LİGASYONU ve Ölçümlerinin Onay <ol><li> Bir 1 L / dak oksijen akış hızı ile, bakım için,% 1.5 - indüksiyon,% 5 izofluran ve 1 - Bir hafta sonra, 3 önceden bantlı fare anestezi. </li><li> tüy dökücü krem ​​kullanarak göğüs tüylerden. İyice ılık su ve pamuk aplikatör ile krem ​​çıkarın. </li><li> 37 ° C&#39;de muhafaza hayvan taşıma platformuna yatar pozisyonda, fare elde edin. pençeleri elektrot jeli uygulayın ve onları elektrotlar ile yastığına bantlayın. </li><li> Fare göğsüne ultrason jeli uygulayın. 40 MHz&#39;lik MS550D prob ve yüksek frekanslı ultrason sistemi ile, aort arkı üzerinde yanı sıra, sol ve sağ karotid arter renkli Doppler ve darbeli dalga Doppler tarama gerçekleştirin. </li><li> B-Modunu Kullanma, sol ventrikül bulun. M-Modunu Kullanma, sistolik ve diyastolik duvar kalınlığı ölçülebilir. gerektiği gibi kullanın Cine Mağaza ve Çerçeve Mağazası verileri ve görüntüleri kaydetmek için. </li><li> UB-Mode şarkı dallanma noktasından önce sol karotis arter bulun. akışını değerlendirmek için darbeli dalga ve renkli Doppler kullanın. Benzer bir noktada sağ karotid artere ile tekrarlayın. Daha sonra analiz etmek Cine Store ve Çerçeve Mağazası modlarında görüntüleri kaydedin. </li><li> Fare sol dekübit pozisyonunda olduğunu şimdiye kadar sola hayvan işleme platformu eğin. Aort arkı bulmak için X ve Y fare, parasternal pozisyonda kafasına bir pozisyon paralel ofset 30 ° hakkında soruşturma yerleştirin ve manipüle. </li><li> daralma bulun. İki karotid arterler aortik arktan şube nerede kan noktası arasında dar bir kanal üzerinden akan olacak gibi, daha görünür daralma site yapmak için renkli Doppler modunu kullanın. </li><li> zirve akış hızını ölçmek için darbeli dalga ve renkli Doppler kullanın. gerektiği gibi kullanın Cine Mağaza ve Çerçeve Mağazası verileri ve görüntüleri kaydetmek için. </li><li> Hayvan yüzüstü pozisyonda bir ısıtma pedi üzerinde kurtarmak için izin verin.tamamen anestezi kurtarıldı sonra 12 saat aydınlık / karanlık döngüsü odasında orijinal kafesine hayvan dönün. </li></ol>

<ol>
	<li>Rockman, H. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Segregation+of+atrial-specific+and+inducible+expression+of+an+atrial+natriuretic+factor+transgene+in+an+in+vivo+murine+model+of+cardiac+hypertrophy.">Segregation of atrial-specific and inducible expression of an atrial natriuretic factor transgene in an in vivo murine model of cardiac hypertrophy.</a> Proc Natl Acad Sci U S A. 88 (18), 8277-8281 (1991).</li><li>de Almeida, A. C., van Oort, R. J., Wehrens, X. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transverse+aortic+constriction+in+mice.">Transverse aortic constriction in mice.</a> J Vis Exp. (38), (2010).</li><li>Hu, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Minimally+invasive+aortic+banding+in+mice:+effects+of+altered+cardiomyocyte+insulin+signaling+during+pressure+overload.">Minimally invasive aortic banding in mice: effects of altered cardiomyocyte insulin signaling during pressure overload.</a> Am J Physiol Heart Circ Physiol. 285 (3), H1261-H1269 (2003).</li><li>Shimizu, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Excessive+cardiac+insulin+signaling+exacerbates+systolic+dysfunction+induced+by+pressure+overload+in+rodents.">Excessive cardiac insulin signaling exacerbates systolic dysfunction induced by pressure overload in rodents.</a> J Clin Invest. 120 (5), 1506-1514 (2010).</li><li>Tarnavski, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mouse+surgical+models+in+cardiovascular+research.">Mouse surgical models in cardiovascular research.</a> Methods Mol Biol. 573, 115-137 (2009).</li><li>Zhang, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+modified+murine+model+for+the+study+of+reverse+cardiac+remodelling.">A modified murine model for the study of reverse cardiac remodelling.</a> Exp Clin Cardiol. 18 (2), e115-e117 (2013).</li><li>Hartley, C. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Doppler+estimation+of+reduced+coronary+flow+reserve+in+mice+with+pressure+overload+cardiac+hypertrophy.">Doppler estimation of reduced coronary flow reserve in mice with pressure overload cardiac hypertrophy.</a> Ultrasound Med Biol. 34 (6), 892-901 (2008).</li><li>Scherrer-Crosbie, M., Thibault, H. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Echocardiography+in+translational+research:+of+mice+and+men.">Echocardiography in translational research: of mice and men.</a> J Am Soc Echocardiogr. 21 (10), 1083-1092 (2008).</li><li>Faerber, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Induction+of+heart+failure+by+minimally+invasive+aortic+constriction+in+mice:+reduced+peroxisome+proliferator-activated+receptor+gamma+coactivator+levels+and+mitochondrial+dysfunction.">Induction of heart failure by minimally invasive aortic constriction in mice: reduced peroxisome proliferator-activated receptor gamma coactivator levels and mitochondrial dysfunction.</a> J Thorac Cardiovasc Surg. 141 (2), 492-500 (2011).</li><li>Li, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assessment+of+Cardiac+Morphological+and+Functional+Changes+in+Mouse+Model+of+Transverse+Aortic+Constriction+by+Echocardiographic+Imaging.">Assessment of Cardiac Morphological and Functional Changes in Mouse Model of Transverse Aortic Constriction by Echocardiographic Imaging.</a> J Vis Exp. (112), (2016).</li></ol>

The authors declare that they have no competing financial interests.

Rockman ve arkadaşları kalbinde basınç aşırı incelemek için bir yöntem olarak aort bantlama için ilk yöntem geliştirmiştir. Bu etkin araştırma hipertansiyon ve kalp yetmezliği 1 hücresel ve moleküler sonuçlarını ortaya çıkarmak için başlayacak. Geliştirilmiş bir yöntem olup, minimal invaziv transvers aortik daralma (MTAC), geleneksel çapraz aort daralma 9 sakıncaları olmayan, sol ventrikül basıncı, aşırı yük ve kalp yetmezliği indüks...

<html> Bu maddenin amacı, genel olarak farelerde aort daralma (TAC), daha basit ve daha uygun cerrahi üretilmesi için değiştirilebilir kadar transvers göstermektir. TAC ilk kez 1991 1 tanıtılan ve manipüle genomları 2, 3, 4, 5, 6 ile özellikle küçük hayvanlarda, sol ventrikül ve kalp yetmezliğine hipertrofisi neden hücresel ve moleküler yolları incelemek için moleküler biyologlar sağlanmıştır. İstenen basınç yükü üretmek onun etkinliğine rağmen, teknik nihai işlemi gerçekleştirmeden ve düşük hayatta kalma oranı ile zorluk ile sınırlıdır. TAC iletken bir cerrah endotrakeal entübasyon, torakotomi gerçekleştirmek ve akciğer çöküşü 1 önlemek için yapay havalandırma kullanmak gerekir. içerik &quot;&gt; Çoğu zaman, basit ve daha az invazif bir yöntem arzu edilmektedir. Sonuç olarak, minimal invaziv enine aort daralma (MTAC) 3 geliştirildi. sonuç (özellikle sol ventrikül hipertrofisi) aynı olmasına rağmen, prosedür önemli ölçüde daha az cihazları içerir ve hayvan daha az zarar. MTAC% 90 üzerinde, büyük bir hayatta kalma oranına sahip bir arzu bir yöntem olduğunu kanıtlamaktadır, ve çok atfedilebilecek olabilir başarılı bir cerrahi sonrası ölüm sadece 15 dakika ila 25. nadir vakaların bir operasyon süresine sahiptir muazzam sol ventrikül yüklenmesinin ve böbrekler gibi kritik organlara kan akımı ölümcül azalmaya neden aort kavsi -tight daralma. Prosedür tamamlandıktan sonra, ekokardiyografi bantlama ve kardiyak morfoloji ve fonksiyon başarısını değerlendirmek için kullanılabilir. Bir yüksek frekans ultrason sistemi çapını ölçmek ve sol ve sağ değişiklikleri akış kullanılabilirzirve akım hızı ölçümleri için aortik ark daralma görselleştirmek için, ve sol ventrikül duvar kalınlığı ve fonksiyonel parametreler 7, 8 belirlemek için, arterler düzeye ulaşmamıştır. Ötenazi sonra, organlar da, hematoksilen ve eozin boyama ve Picrosirius kollajen boyama ile histopatolojik çalışmalar için toplanan olabilir ikinci fibrozis gözlem için özellikle yararlı olmak.

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			<td>27 Gauge Needle</td>
			<td>BD, Franklin Lakes, NJ 07417, USA.&#160;</td>
			<td>301629</td>
			<td>Make blunt and smooth for spacer</td>
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			<td>6/0 Dafilon</td>
			<td>B. Braun, 34212 Melsungen, Hessen, Germany.</td>
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			<td>Sterile gloves</td>
			<td>A.R. Medicom, Inc (Asia), Hong Kong.</td>
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			<td>Cotton Applicator</td>
			<td>Mannings, Quarry Bay, Hong Kong.</td>
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			<td>Local Shopping Center</td>
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			<td>Veet (Hong Kong), Kwun Tong, Kowloon, Hong Kong</td>
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			<td>FST, British Columbia V7H 0A6, Canada.</td>
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			<td>Micro Olsen-Hegar Needle Holder</td>
			<td>WPI, Sarasota, FL 34240, USA.&#160;</td>
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			<td>Stereo Micrioscope</td>
			<td>WPI, Sarasota, FL 34240, USA.&#160;</td>
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			<td>GenTeal Gel</td>
			<td>Novartis, East Hanover, NJ 07936, USA.&#160;</td>
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			<td>Heating Pad</td>
			<td>Kent Scientific Corporation, Torrington, CT 06790, USA.&#160;</td>
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			<td>Surgical tape</td>
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			<td>Buprenorphine</td>
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minimally invasive transverse aortic constriction in mice

Minimal invaziv enine aort daralma (MTAC) standart açık-göğüs enine aort daralma (TAC) daha farelerde enine aorta daralması için daha uygun bir yöntemdir. enine aort daralma sol ventrikül yüksek basınç indüksiyon için son derece işlevsel bir yöntem olmasına rağmen, bunun nedeni trakeal entübasyon ile suni havalandırma kullanımı için daha zor ve uzun bir prosedürdür. TAC yeni yöntemde, kumanda merkezinde olduğu gibi, aynı zamanda çoğu kez daha az survivable olduğunu ne bir havalandırma kurulum ile kaburga ve interkostal kaslar ne entübasyon kesim gerektirir. Göğüs boşluğuna erişmek için bir torakotomi aksine kumanda merkezinde, aortik ark boynun ön bölgesinde orta hat kesiden ulaşılır. Tiroid sternum çentik ortaya çıkarmak için geri çekilir. sternum daha sonra ikinci kaburga seviyesine kadar kesilir ve aortik ark bağ dokuları ve timus ayırarak sadece ulaşılır. itibarenOrada, bir dikiş kemer sarılı ve bir ayırıcı ile bağlı ve daha sonra sternum kesim ve cilt kapalı edilebilirler. MTAC sol ventrikül hipertansiyon ikna etmek için çok daha hızlı ve daha az invaziv bir yoludur ve yüksek verimli çalışmalar için olanak sağlar. daralma başarısı aort kavsi akış hızlarını belirlemek için yüksek frekanslı trans-torasik ekokardiyografi, özellikle renkli Doppler ve darbeli dalga Doppler kullanılarak doğrulandı ve sol olabilir sağ karotid arter, kan damarlarının boyut ve sol ventrikül fonksiyonu ve morfolojisi. Başarılı bir daralma aynı zamanda interstisyel ve perivasküler fibrozis ile kalp kası hücresi hipertrofisi olarak önemli histopatolojik değişiklikler, tetikleyecektir. Burada, kumanda merkezinde prosedürü karotid arterlerde ortaya çıkan akımı değişiklikleri ekokardiyografi, brüt morfolojisi ve kalbinde histopatolojik değişiklikler incelenmiştir nasıl gösteren tarif edilmektedir.

MTAC zamanında sol ventrikül önemli hipertansiyon indüksiyon sağlar. Poliüretan tüp ile yerine bükülüp yapılacak 4 ila 30-gauge iğne - Şekil 1 &#39;de görüldüğü gibi, işlem için birincil araçların hazırlanması sadece 2 gerektiren basit ve az. cerrahi prosedür kendisi TAC ile karşılaştırıldığında, ve kolayca yapılabilir gibi, aynı zamanda daha az karmaşıktır. Tiroid geri ed...

Watch this Scientific Journal Video about Minimally Invasive Transverse Aortic Constriction in Mice at JoVE.com

Minimally Invasive Transverse Aortic Constriction in Mice

entübasyon ile bir vantilatör kullanımını ortadan kaldırırken Minimal invaziv enine aort daralma (MTAC) normal enine aort daralma (TAC) temellerini korur. Özellikle translasyonel çalışmalarda sol ventrikül aşırı, yüksek verimli çalışmalar için oldukça aranan bir yöntem olduğu kanıtlanmıştır.

Farelerde Minimal İnvaziv Enine Aort Konstrüksiyon

Minimally invasive transverse aortic constriction (MTAC) is a more desirable method for the constriction of the transverse aorta in mice than standard ...

minimally-invasive-transverse-aortic-constriction-in-mice

Research

JoVE Journal

Medicine

20.3K Görüntüleme.  The University of Hong Kong.  entübasyon ile bir vantilatör kullanımını ortadan kaldırırken Minimal invaziv enine aort daralma (MTAC) normal enine aort daralma (TAC) temellerini korur. Özellikle translasyonel çalışmalarda sol ventrikül aşırı, yüksek verimli çalışmalar için oldukça aranan bir yöntem olduğu kanıtlanmıştır. 

Video: Minimally Invasive Transverse Aortic Constriction in Mice

In vitro Measurements of Tracheal Constriction Using Mice

Transgenic and knockout mice have been powerful tools for the investigation of the physiology and pathophysiology of airways1,2. In vitro tensometry of isolated tracheal preparations has proven to be a useful assay of airway smooth muscle (ASM) contractile response in genetically modified mice. These in vitro tracheal preparations are relatively simple, provide a robust response, and retain both functional cholinergic nerve endings and muscle responses, even after long incubations.
Tracheal tensometry also provides a functional assay to study a variety of second messenger signaling pathways that affect contraction of smooth muscle. Contraction in trachea is primarily mediated by parasympathetic, cholinergic nerves that release acetylcholine onto ASM (Figure 1). The major ASM acetylcholine receptors are muscarinic M2 and M3 which are Gi/o and Gq coupled receptors, respectively3,4,5. M3 receptors evoke contraction by coupling to Gq to activate phospholipase C, increase IP3 production and IP3-mediated calcium release from the sarcoplasmic reticulum3,6,7. M2/Gi/o signaling is believed to enhance contractions by inhibition of adenylate cyclase leading to a decrease in cAMP levels5,8,9,10. These pathways constitute the so called "pharmaco-contraction coupling" of airway smooth muscle11. In addition, cholinergic signaling through M2 receptors (and modulated by M3 signaling) involves pathways that depolarize the ASM which in turn activate L-type, voltage-dependent calcium channels (Figure 1) and calcium influx (so called "excitation-contraction coupling")4,7. More detailed reviews on signaling pathways controlling airway constriction can be found4,12. The above pathways appear to be conserved between mice and other species. However, mouse tracheas differ from other species in some signaling pathways. Most prominent is their lack of contractile response to histamine and adenosine13,14, both well-known ASM modulators in humans and other species5,15.
Here we present protocols for the isolation of murine tracheal rings and the in vitro measurement of their contractile output. Included are descriptions of the equipment configuration, trachea ring isolation and contractile measurements. Examples are given for evoking contractions indirectly using high potassium stimulation of nerves and directly by depolarization of ASM muscle to activate voltage-dependent calcium influx (1. high K+, Figure 1). In addition, methods are presented for stimulations of nerves alone using electric field stimulation (2. EFS, Figure 1), or for direct stimulation of ASM muscle using exogenous neurotransmitter applied to the bath (3. exogenous ACH, Figure 1). This flexibility and ease of preparation renders the isolated trachea ring model a robust and functional assay for a number of signaling cascades involved in airway smooth muscle contraction.

In vitro Measurements of Tracheal Constriction Using Mice

Transgenic mice have been extremely useful in ascribing physiological function to genes. As such, research in general, and functional studies of airway, in particular, have undergone a remarkable shift toward murine models. Here we provide protocols for in vitro trachea constriction studies to evaluate smooth muscle function in murine airway.

Fare kullanarak Trakeal Konstrüksiyon in vitro ölçümleri ise

Transgenic and knockout mice have been powerful tools for the investigation of the physiology and pathophysiology of airways1,2. In vitro tensometry of ...

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Ascending Aortic Constriction in Rats for Creation of Pressure Overload Cardiac Hypertrophy Model

Ascending aortic constriction is the most common and successful surgical model for creating pressure overload induced cardiac hypertrophy and heart failure. Here, we describe a detailed surgical procedure for creating pressure overload and cardiac hypertrophy in rats by constriction of the ascending aorta using a small metallic clip. After anesthesia, the trachea is intubated by inserting a cannula through a half way incision made between two cartilage rings of trachea. Then a skin incision is made at the level of the second intercostal space on the left chest wall and muscle layers are cleared to locate the ascending portion of aorta. The ascending aorta is constricted to 50&#8211;60% of its original diameter by application of a small sized titanium clip. Following aortic constriction, the second and third ribs are approximated with prolene sutures. The tracheal cannula is removed once spontaneous breathing was re-established. The animal is allowed to recover on the heating pad by gradually lowering anesthesia. The intensity of pressure overload created by constriction of the ascending aorta is determined by recording the pressure gradient using trans-thoracic two dimensional Doppler-echocardiography. Overall this protocol is useful to study the remodeling events and contractile properties of the heart during the gradual onset and progression from compensated cardiac hypertrophy to heart failure stage.

We describe a stepwise procedure for creating pressure overload and left ventricular hypertrophy in Wistar rats by constriction of the ascending aorta using a small metallic clip. This model is extensively used for studying remodeling changes during cardiac hypertrophy and for identifying and evaluating strategies for regression of such changes.

Basınç Aşırı Kardiyak hipertrofi Modeli Oluşturma Ratlarda Aort daralma, Artan

Ascending aortic constriction is the most common and successful surgical model for creating pressure overload induced cardiac hypertrophy and heart ...

Minimally Invasive Establishment of Murine Orthotopic Bladder Xenografts

Orthotopic bladder cancer xenografts are the gold standard to study molecular cellular manipulations and new therapeutic agents&#160;in vivo. Suitable cell lines are inoculated either by intravesical instillation (model of nonmuscle invasive growth) or intramural injection into the bladder wall (model of invasive growth). Both procedures are complex and highly time-consuming. Additionally, the superficial model has its shortcomings due to the lack of cell lines that are tumorigenic following instillation. Intramural injection, on the other hand, is marred by the invasiveness of the procedure and the associated morbidity for the host mouse.
With these shortcomings in mind, we modified previous methods to develop a minimally invasive approach for creating orthotopic bladder cancer xenografts. Using ultrasound guidance we have successfully performed percutaneous inoculation of the bladder cancer cell lines UM-UC1, UM-UC3 and UM-UC13 into 50 athymic nude. We have been able to demonstrate that this approach is time efficient, precise and safe. With this technique, initially a space is created under the bladder mucosa with PBS, and tumor cells are then injected into this space in a second step. Tumor growth is monitored at regular intervals with bioluminescence imaging and ultrasound. The average tumor volumes increased steadily in in all but one of our 50 mice over the study period.
In our institution, this novel approach, which allows bladder cancer xenograft inoculation in a minimally-invasive, rapid and highly precise way, has replaced the traditional model.

The established technique to inoculate primary invasive orthotopic bladder cancer xenografts requires laparotomy and mobilization of the bladder. This procedure inflicts significant morbidity on the mice, is technically challenging and time-consuming. We therefore developed a high-precision, percutaneous approach utilizing ultrasound guidance.

Kemirgen Ortotopik Mesane ksenogratflarının Minimal İnvaziv kurulması

Orthotopic bladder cancer xenografts are the gold standard to study molecular cellular manipulations and new therapeutic agents&#160;in vivo. Suitable ...

Encapsulation Thermogenic Preadipocytes for Transplantation into Adipose Tissue Depots

Cell encapsulation was developed to entrap viable cells within semi-permeable membranes. The engrafted encapsulated cells can exchange low molecular weight metabolites in tissues of the treated host to achieve long-term survival. The semipermeable membrane allows engrafted encapsulated cells to avoid rejection by the immune system. The encapsulation procedure was designed to enable a controlled release of bioactive compounds, such as insulin, other hormones, and cytokines. Here we describe a method for encapsulation of catabolic cells, which consume lipids for heat production and energy dissipation (thermogenesis) in the intra-abdominal adipose tissue of obese mice. Encapsulation of thermogenic catabolic cells may be potentially applicable to the prevention and treatment of obesity and type 2 diabetes. Another potential application of catabolic cells may include detoxification from alcohols or other toxic metabolites and environmental pollutants.

Here, we present a protocol for encapsulation of catabolic cells, which consume lipids for heat production in intra-abdominal adipose tissue and increase energy dissipation in obese mice.

Yağ Dokusu Depolarında içine Nakli Enkapsülasyon termojenik Preadipositler

Cell encapsulation was developed to entrap viable cells within semi-permeable membranes. The engrafted encapsulated cells can exchange low molecular ...

Assessment of Cardiac Morphological and Functional Changes in Mouse Model of Transverse Aortic Constriction by Echocardiographic Imaging

Transverse aortic constriction (TAC) in mice has been used as a valuable model to study mechanisms of cardiac hypertrophy and heart failure1. A reliable noninvasive method is essential to assess real-time cardiac morphological and functional changes in animal models of heart disease. Transthoracic echocardiography represents an important tool for noninvasive assessment of cardiac structure and function2. Here we used a high-resolution ultrasound imaging system to monitor myocardial remodeling and heart failure progression over time in a mouse model of TAC. B-mode, M-mode, and Doppler imaging were used to precisely assess cardiac hypertrophy, ventricular dilatation, and functional deterioration in mice following TAC. Color and pulse wave (PW) Doppler imaging was used to noninvasively measure pressure gradient across the aortic constriction created by TAC and to assess transmitral blood flow in mice. Thus transthoracic echocardiographic imaging provides comprehensive noninvasive measurements of cardiac dimensions and function in mouse models of heart disease.

The goal of this protocol is to noninvasively assess cardiac structural and functional changes in a mouse model of heart disease created by transverse aortic constriction, using B- and M-mode echocardiography and color/pulse wave Doppler imaging.

Ekokardiyografik Imaging tarafından Enine Aort Konstrüksiyon Mouse Modeli Kardiyak Morfolojik Değerlendirilmesi ve Fonksiyonel Değişiklikler

Transverse aortic constriction (TAC) in mice has been used as a valuable model to study mechanisms of cardiac hypertrophy and heart failure1. A reliable ...

Technique of Minimally Invasive Transverse Aortic Constriction in Mice for Induction of Left Ventricular Hypertrophy

Transverse aortic constriction (TAC) in mice is one of the most commonly used surgical techniques for experimental investigation of pressure overload-induced left ventricular hypertrophy (LVH) and its progression to heart failure. In the majority of the reported investigations, this procedure is performed with intubation and ventilation of the animal which renders it demanding and time-consuming and adds to the surgical burden to the animal. The aim of this protocol is to describe a simplified technique of minimally invasive TAC without intubation and ventilation of mice. Critical steps of the technique are emphasized in order to achieve low mortality and high efficiency in inducing LVH.
Male C57BL/6 mice (10-week-old, 25-30 g, n=60) were anesthetized with a single intraperitoneal injection of a mixture of ketamine and xylazine. In a spontaneously breathing animal following a 3-4 mm upper partial sternotomy, a segment of 6/0 silk suture threaded through the eye of a ligation aid was passed under the aortic arch and tied over a blunted 27-gauge needle. Sham-operated animals underwent the same surgical preparation but without aortic constriction. The efficacy of the procedure in inducing LVH is attested by a significant increase in the heart/body weight ratio. This ratio is obtained at days 3, 7, 14 and 28 after surgery (n = 6 - 10 in each group and each time point). Using our technique, LVH is observed in TAC compared to sham animals from day 7 through day 28. Operative and late (over 28 days) mortalities are both very low at 1.7%.
In conclusion, our cost-effective technique of minimally invasive TAC in mice carries very low operative and post-operative mortalities and is highly efficient in inducing LVH. It simplifies the operative procedure and reduces the strain put on the animal. It can be easily performed by following the critical steps described in this protocol.

The aim of this protocol is to describe step-by-step the technique of minimally invasive transverse aortic constriction (TAC) in mice. By elimination of intubation and ventilation which are mandatory for the commonly used standard procedure, minimally invasive TAC simplifies the operative procedure and reduces the strain put on the animal.

Minimal invaziv transvers aort daralma farelerde sol ventrikül hipertrofisi indüksiyon için tekniği

Transverse aortic constriction (TAC) in mice is one of the most commonly used surgical techniques for experimental investigation of pressure ...

A Minimally Invasive Model to Analyze Endochondral Fracture Healing in Mice Under Standardized Biomechanical Conditions

Bone healing models are necessary to analyze the complex mechanisms of fracture healing to improve clinical fracture treatment. During the last decade, an increased use of mouse models in orthopedic research was noted, most probably because mouse models offer a large number of genetically-modified strains and special antibodies for the analysis of molecular mechanisms of fracture healing. To control the biomechanical conditions, well-characterized osteosynthesis techniques are mandatory, also in mice. Here, we report on the design and use of a closed bone healing model to stabilize femur fractures in mice. The intramedullary screw, made of medical-grade stainless steel, provides through fracture compression an axial and rotational stability compared to the mostly used simple intramedullary pins, which show a complete lack of axial and rotational stability. The stability achieved by the intramedullary screw allows the analysis of endochondral healing. A large amount of callus tissue, received after stabilization with the screw, offers ideal conditions to harvest tissue for biochemical and molecular analyses. A further advantage of the use of the screw is the fact that the screw can be inserted into the femur with a minimally invasive technique without inducing damage to the soft tissue. In conclusion, the screw is a unique implant that can ideally be used in closed fracture healing models offering standardized biomechanical conditions.

This protocol describes a minimally invasive osteosynthesis technique using an intramedullary screw for standardized stabilization of femur fractures, which can be used to analyze endochondral bone healing in mice.

Endochondral standart biyomekanik koşullar altında farelerde şifa kırık çözümlemek için minimal invaziv bir Model

Bone healing models are necessary to analyze the complex mechanisms of fracture healing to improve clinical fracture treatment. During the last decade, an ...

A Closed-chest Model to Induce Transverse Aortic Constriction in Mice

Research on cardiac hypertrophy and heart failure is frequently based on pressure overload mouse models induced by TAC. The standard procedure is to perform a partial thoracotomy to visualize the transverse aortic arch. However, the surgical trauma caused by the thoracotomy in open-chest models changes the respiratory physiology as the ribs are dissected and left unattached after chest closure. To prevent this, we established a minimally invasive, closed chest approach via lateral thoracotomy. Herein we approach the aortic arch via the 2nd intercostal space without entering the chest cavities, leaving the mouse with a less traumatic injury to recover from. We perform this operation using standard laboratory settings for open chest TAC procedures with equal survival rates. Apart from maintaining physiological breathing patterns due to the closed chest approach, the mice seem to benefit by showing rapid recovery, as the less invasive technique appears to facilitate a fast healing process and to reduce immune response after trauma.

Here, we present a protocol of Transverse Aortic constriction (TAC) via a lateral thoracotomy. This technique is a minimally invasive, closed chest surgical procedure aiming to simulate pressure overload and heart failure in mice utilizing standard TAC laboratory settings.

Transvers aort daralma farelerde ikna etmek için kapalı-göğüs manken

Research on cardiac hypertrophy and heart failure is frequently based on pressure overload mouse models induced by TAC. The standard procedure is to ...

A Pre-clinical Rat Model for the Study of Ischemia-reperfusion Injury in Reconstructive Microsurgery

Ischemia-reperfusion injury is the main cause of flap failure in reconstructive microsurgery. The rat is the preferred preclinical animal model in many areas of biomedical research due to its cost-effectiveness and its translation to humans. This protocol describes a method to create a preclinical free skin flap model in rats with ischemia-reperfusion injury. The described 3 cm x 6 cm rat free skin flap model is easily obtained after the placement of several vascular ligatures and the section of the vascular pedicle. Then, 8 h after the ischemic insult and completion of the microsurgical anastomosis, the free skin flap develops the tissue damage. These ischemia-reperfusion injury-related damages can be studied in this model, making it a suitable model for evaluating therapeutic agents to address this pathophysiological process. Furthermore, two main monitoring techniques are described in the protocol for the assessment of this animal model: transit-time ultrasound technology and laser speckle contrast analysis.

Here, we describe a pre-clinical animal model for studying the pathophysiology of ischemia-reperfusion injury in reconstructive microsurgery. This free skin flap model based on the superficial caudal epigastric vessels in the rat may also allow for the evaluation of different therapies and compounds to counteract ischemia-reperfusion injury-related damage.

Rekonstrüktif Mikrocerrahide İskemi-Reperfüzyon Hasarı Nın İnceleştirilmesinde Klinik Öncesi Sıçan Modeli

Ischemia-reperfusion injury is the main cause of flap failure in reconstructive microsurgery. The rat is the preferred preclinical animal model in many ...

Evaluation of Capnography Sampling Line Compatibility and Accuracy when Used with a Portable Capnography Monitor

Capnography is commonly used to monitor patient&#8217;s ventilatory status. While sidestream capnography has been shown to provide a reliable assessment of end-tidal CO2 (ETCO2), its accuracy is commonly validated using commercial kits composed of a capnography monitor and its matching disposable nasal cannula sampling lines. The purpose of this study was to assess the compatibility and accuracy of cross-paired capnography sampling lines with a single portable bedside capnography monitor. A series of 4 bench tests were performed to evaluate the tensile strength, rise time, ETCO2 accuracy as a function of respiratory rate, and ETCO2 accuracy in the presence of supplemental O2. Each bench test was performed using specialized, validated equipment to allow for a full evaluation of sampling line performance. The 4 bench tests successfully differentiated between sampling lines from different commercial sources and suggested that due to increased rise time and decreased ETCO2 accuracy, not all nasal cannula sampling lines provide reliable clinical data when cross-paired with a commercial capnography monitor. Care should be taken to ensure that any cross-pairing of capnography monitors and disposable sampling lines is fully validated for use across respiratory rates and supplemental O2 flow rates commonly encountered in clinical settings.

The goal of this study was to evaluate the accuracy of capnography sampling lines used in conjunction with a portable bedside capnography monitor. Sampling lines from 7 manufacturers were evaluated for tensile strength, rise time, and ETCO2 accuracy as a function of respiratory rate or supplemental oxygen flow rate.

Taşınabilir Kapnografi Monitörü ile Kullanıldığında Kapnografi Örnekleme Hattı Uyumluluğunun ve Doğruluğunun Değerlendirilmesi

Capnography is commonly used to monitor patient&#8217;s ventilatory status. While sidestream capnography has been shown to provide a reliable assessment ...