Yazarlar bu deneysel modelin gelişimini desteklemek için, sırasıyla, işletme hibesi ve kuruluş fonu Tıbbi Araştırma Sağlık Araştırması (MOP53116) ve Alberta Heritage Vakfı Kanada Enstitüleri teşekkür etmek istiyorum.

1. Anestezi <ol><li> 2L/min de anestetik makinenin akış hızını ayarlar. Vakum emiş egzoz bağlayın. </li><li> % 5 anestezi gazı (İzofluran) (~ 3 dk) ile Şarj yüz maskesi. </li><li> Yenidoğan domuz% 100 oksijen (~ 3 dk) inhale İzofluran% 5 ile teşvik edilecektir. </li><li> İzofluran% 2-3 de anestezi koruyun. Uygun olarak% 0.5 ile Isoflurane ince ayarı, ancak 0.5 ila 5 &#39;den% domuz yavrusu durumuna bağlı olarak değişebilir. </li><li> Vasküler erişim bir kez kurulduktan sonra, inhalasyon anestezisi fentanil (5-50 mcg / kg / h) ve midazolam (200-500 mcg / kg / saat) infüzyon kullanarak intravenöz anestezi geçirilebilir. Panküronyum (50-100 mcg / kg / h) anestezik ilaçların ayarlanması için korunur hayvanın durumunu gözlemlemek yeteneği iken, ameliyat sırasında aşırı kas hareketlerini kontrol etmek gerekebilir. </li><li> Piglet (perkütan oksijen lar pulse oksimetre ile monitörize edildi% 95-100 at aturation) ve EKG (130-170 atım / dk kalp hızı). </li><li> Piglet en rektal sıcaklık 38-40 tutulur ısıtma battaniye ve radyant ısıtıcı ile ° C. </li><li> Piglet ve anestezik durumu düzenli davranışsal (ajitasyon), kardiyovasküler (taşikardi ve hipertansiyon) ve solunum (takipne) parametrelerin uygun olarak, nörolojik (pupilla büyüklüğü, yırtılma, vücut hareketleri) kullanarak deney süresi boyunca değerlendirilmektedir. Minimal felç verilir. Felç olan ve olmayan domuz yavrularında anestezi Önceki deneyimi değerlendirilmesi için yararlı olacaktır. </li><li> Protokol pentobarbital (100 mg / kg) intravenöz olarak bir aşırı ile deney sonunda, hayvanın euthanization olmayan bir hayatta kalma bir işlemdir. </li></ol> 2. Kasık damar kateterleri cerrahi yerleştirme (Şekil 1) <ol><li> Sağ kasık uzun 2-3cm kesi olun. </li><li> Sağ femoral ven ve 1cm righ 1cm teşriht femoral arter. Her geminin etrafında iki 3-0 dizeleri koyun. </li><li> Sağ femoral ven kateterizasyonu: ven distal Arter. 15cm bir Argyle kateter (3,5 veya 5 Fransız, çift lümenli) (Covidien, Mansfield, MA) takın ve bu sağ atrium de yerleştirecektir. Kateter sabitlemek için iki dizeleri bağla. Kateter bakımı sıvı ve ilaç infüzyonu (ikincil port) ve venöz / sağ atriyal basınç ölçümü (birincil port) santral için kullanılabilir. </li><li> Sağ femoral arter kateterizasyonu: arterin distal Arter. Kan akışını durdurmak için proksimal dize yukarı kaldırın. 5cm bir Argyle kateter (3,5 veya 5 Fransız, tek lümenli) takın. Bu sürekli ortalama arter basınç ölçümü ve kan örneklemesi için infra-renal aorta de arteryel kateter yerleştirir. Kateter sabitlemek için iki dizeleri bağla. </li><li> Cilt kapatın. </li></ol> 3. Mekanik ventilasyon (Şekil 2) Kurmak <ol><li> Uzun 2-3cm yatay Yapboyun insizyonu. </li><li> Inceleyin ve trakeanın 1cm maruz kalmaktadır. Trakea etrafında iki 1-0 dizeleri koyun. </li><li> Trakea içine 1cm bir endotrakeal tüp (3.0 veya 3.5) yerleştirin. Bir ventilatör bağlanın ve mekanik ventilasyon başlar. Endotrakeal tüp sabitleyin. </li><li> Inceleyin ve karotis arter maruz kalmaktadır. Sürekli kan akımını ölçmek için bir transit zamanlı ultrason akış probu (2SB veya 2RB, Transonik Systems Inc, Ithica, NY) ile damar çevreler. </li></ol> 4. Mezenterik az akış sondaları yerleştirilmesi (Şekil 3) ve sol renal (Şekil 4) arterler <ol><li> Fentanil (5-10 mcg / kg) ve Acepromazine (0,01-0,02 mg / kg) öncesinde cilt insizyonu için gerekli olan ekstra dozları. </li><li> Uzun bir subkostal-kanadını kesi olun ve dikkatli bir şekilde kas tabakaları teşrih. </li><li> Abdominal aorta Açığa. </li><li> Vasküler işleme (vazospazm) ve lenfatik hasarı en aza indirin. </li><li> 0.5-1cm süperior mezenterik arter ve teşrihetrafında bir transonik akış prob (3SB) koyun. </li><li> 0.5-1cm sol renal arter inceleyin ve çevresinde bir transonik akış prob (2SB) koyun. </li><li> Cilt kapatın ve akış prob sabitleyin. </li></ol> 5. Pulmoner arter kateterinin yerleştirilmesi (Şekil 5) ve akım probu (Şekil 6) <ol><li> Fentanil (5-10 mcg / kg) ve Acepromazine (0,01-0,02 mg / kg) öncesinde cilt insizyonu için gerekli olan ekstra dozları. </li><li> Sağ yanal konumda hayvan Lie. </li><li> Sol 4. interkostal aralıktan torakotomi. </li><li> Gerekirse internal meme arter ve ven dikkat, Arter. </li><li> Sol akciğerde bastırın ve gerektiğinde oksijen artırmak için bir diş bezi kullanın. </li><li> Perikard açın. </li><li> Duktus arteriozus pulmoner arterden aortaya çalıştığı belirleyin. </li><li> Ductus arteriosus bir klip koyarak veya aslına bir kalın &quot;3-O ipek&quot; kravat bağlandı olabilir. </li><li> Ücretsiz ana pulmoner arter ve pas avkalın bir &quot;0&quot; bağını kullanarak ascular sapan. </li><li> Pulmoner arter kateterinin yerleştirilmesi için üssünde bir çanta dize (5-0 prolen) sütür gerçekleştirin. </li><li> 1 cm maksimum çanta dize aracılığıyla 20G Angiocath (kateter ucunun 1 cm az 3 tarafı delikli) takın. </li><li> Venöz kan serbest akışını kontrol edin. </li><li> Basınç dönüştürücü bağlan, pulmoner arter basıncı ve dalga kontrol edin. </li><li> Çanta dize sıkın ve pulmoner kateter sabitleyin. </li><li> Ana pulmoner arter etrafında bir transonik akış prob (6SB) yerleştirin. </li><li> Akış prob ve optimum sinyal iletimi için izin arter arasındaki ultrasonik jel yerleştirin. </li><li> Nemli tuzlu gazlı bez ile yarayı örtün. </li></ol> 6. Hipoksi ve reoksijenasyon protokolü <ol><li> Hipoksemi indüklemek için solunan gazın azot konsantrasyonu artar ile% 10, alınan oksijenin konsantrasyonunu azaltır. </li><li> Solunan oksijen ayarlayın% 10 ile% 15 arasındaki konsantrasyon 2 saat boyunca% 30-40, 20-40 mm Hg ya da SaO içinde bir 2 PaO2 elde edilir. </li><li> PaCO2 değerlendirmek ve buna göre ventilatör hızını ayarlamak için kan analizi gerçekleştirin. </li><li> Hipoksemi indüksiyon ile ilk saat sürekli bir taşikardik (ve kardiyak output) cevabı uyandırmaya adamıştır. </li><li> Karotis, superior mezenterik ve sol renal arterlerde kan akımı değişiklikleri izlemek için devam edin. </li><li> Hipoksi ikinci saatinde, hipoksik stres bazal% 30-40 giderek daha düşük kardiyak debi artar, 30-35 mmHg ve arteriyel pH 6,95-7,05 için ortalama arter basıncı. </li><li> Hipoksik stres erken sonlandırılması veya uygun şekilde 15 dakika daha uzatılabilir. </li><li> Saf oksijen devam ederken aniden% 100, azot gazı kesilince aniden solunan oksijen konsantrasyonu artırır. </li><li> Arter basıncı ve diğer hemodinamik para demek, kardiyak output Monitörhızlı iyileşme için metre. </li><li> % 100 oksijen ile canlandırma 0.5h devam edilebilir. Bu süre sonrasında,% 21 hızla solunan oksijen konsantrasyonunu azaltır. </li><li> Deney kalan süre için% 21 oksijen reoksijenasyon devam edin. Gerekirse solunan oksijen konsantrasyonu% 25 ile titre edilebilir. </li><li> 10 ml / kg Ringer laktat çözeltisi sıvı bolus deney süresi boyunca uygun olarak gerekli olabilir. Kullanımı protokollerle gerekmektedir. </li></ol> 7. Temsilcisi Sonuçlar: Hipoksinin ilk saatten fazla yenidoğan piglet hipoksemi indüksiyonu 120% -130 bazal% (Şekil 7A) ve kalp hızı (Şekil 7B) için kardiyak output (pulmoner arter akım) artmalıdır. Tipik olarak, kardiyak output ilk 0.5h ve hipoksi 1s arasında zirveye tazminat ulaşmalıdır. Ayrıca, kan akışı merkezi haline gelmelidir beni azaldısenteric ve renal perfüzyon ama korunmuş veya artmış karotis arter akımı (Şekil 8). Hipoksi ikinci saatinde meydana veya aritmi olmadan kalp hızının yavaşlaması kalp debisi sürekli bir azalma, hipotansiyon gelişmesi (Şekil 9A) vardır. Hipoksi bazen kardiyak output azaldıkça hipoksi son 30 dakika içinde düşürebilir artmış pulmoner arter basıncı (Şekil 9B), pulmoner hipertansiyon ile teşvik edilmelidir. Resüsitasyon üzerine, tüm hemodinamik parametreler derhal giderek reoksijenasyonun ilk saatten fazla kurtarır böbrek kan akımı dışında normoksik başlangıca kurtaracaktır. Ancak, özellikle kalp debisi ve ortalama arter basınçları hemodinamik parametreler giderek sırasıyla normoksik bazal ve 35-45 mmHg 70-75 yaklaşık% reoksijenasyonun ilk 2 saatten fazla bozulacaktır. Bu kardiyovasküler dysfunctien azından böyle bir vazoaktif ve inotropik ajanlar olarak miyokardiyal stunning ve garanti kardiyovasküler destekleyici tedaviler için kısmındadır. <img alt="Şekil 1" src="/files/ftp_upload/3166/3166fig1.jpg" /> Şekil 1: femoral arteriyel ve venöz kateter yerleştirme ile Kasık kesi <img alt="Şekil 2," src="/files/ftp_upload/3166/3166fig2.jpg" /> Şekil 2: karotis arter etrafında bir endotrakeal tüp yerleştirilmesi ve bir akış probu ile Boyun kesi <img alt="Şekil 3" src="/files/ftp_upload/3166/3166fig3.jpg" /> Şekil 3: superior mezenterik arterin izolasyon ile Flank kesi <img alt="Şekil 4," src="/files/ftp_upload/3166/3166fig4.jpg" /> Şekil 4: sol renal arter izolasyon ile Flank kesi <img alt="Şekil 5," sRc = &quot;/ files/ftp_upload/3166/3166fig5.jpg&quot; /&gt; Şekil 5: pulmoner arter kateter yerleştirme ile Torakotomi <img alt="Şekil 6" src="/files/ftp_upload/3166/3166fig6.jpg" /> Şekil 6: ana pulmoner arter etrafında bir Transonik Akış probunun yerleştirilmesi ile Torakotomi <img alt="Şekil 7" src="/files/ftp_upload/3166/3166fig7.jpg" /> Şekil 7: (A) kardiyak output (pulmoner arter akım) ve (B) kalp hızı ve hipoksi reoksijenasyon sırasında Zamansal değişimler <img alt="Şekil 8," src="/files/ftp_upload/3166/3166fig8.jpg" /> Şekil 8: (A) karotis az kan akımı Zamansal değişimler, (B) superior mezenterik ve hipoksi reoksijenasyon sırasında (C) sol renal arterlerde <img alt="Şekil 9" src="/files/ftp_upload/3166/3166fig9.jpg" /> Şekil 9: Temporaldeğişiklikleri (A) ortalama arter basıncı ve hipoksi reoksijenasyon sırasında (B) pulmoner arter basıncı

<ol>
	<li>Borke, W. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Increased+myocardial+matrix+metalloproteinases+in+hypoxic+newborn+pigs+during+resuscitation:+effects+of+oxygen+and+carbon+dioxide.">Increased myocardial matrix metalloproteinases in hypoxic newborn pigs during resuscitation: effects of oxygen and carbon dioxide.</a> Eur. J. Clin. Invest. 34, 459-466 (2004).</li><li>Munkeby, B. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Resuscitation+of+hypoxic+piglets+with+100%+O2+increases+pulmonary+metalloproteinases+and+IL-8.">Resuscitation of hypoxic piglets with 100% O2 increases pulmonary metalloproteinases and IL-8.</a> Pediatr. Res. 58, 542-548 (2005).</li><li>Haaland, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Posthypoxic+hypothermia+in+newborn+piglets.">Posthypoxic hypothermia in newborn piglets.</a> Pediatr. Res. 41, 505-512 (1997).</li><li>Haase, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Resuscitation+with+100%+oxygen+causes+intestinal+glutathione+oxidation+and+reoxygenation+injury+in+asphyxiated+newborn+piglets.">Resuscitation with 100% oxygen causes intestinal glutathione oxidation and reoxygenation injury in asphyxiated newborn piglets.</a> Ann. Surg. 240, 364-373 (2004).</li><li>Stevens, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Resuscitation+with+21%+or+100%+oxygen+is+equally+effective+in+restoring+perfusion+and+oxygen+metabolism+in+hypoxic+newborn+piglet+liver.">Resuscitation with 21% or 100% oxygen is equally effective in restoring perfusion and oxygen metabolism in hypoxic newborn piglet liver.</a> Shock. 27, 657-662 (2007).</li><li>Johnson, S. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=N-acetylcysteine+improves+the+hemodynamics+and+oxidative+stress+in+hypoxic+newborn+pigs+reoxygenated+with+100%+oxygen.">N-acetylcysteine improves the hemodynamics and oxidative stress in hypoxic newborn pigs reoxygenated with 100% oxygen.</a> Shock. 28, 484-490 (2007).</li><li>Chapados, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Plasma+cortisol+response+to+ACTH+challenge+in+hypoxic+newborn+piglets+resuscitated+with+21%+and+100%+oxygen.">Plasma cortisol response to ACTH challenge in hypoxic newborn piglets resuscitated with 21% and 100% oxygen.</a> Shock. 33, 519-525 (2010).</li><li>Cheung, P. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Platelet+dysfunction+in+asphyxiated+newborn+piglets+resuscitated+with+21%+and+100%+oxygen.">Platelet dysfunction in asphyxiated newborn piglets resuscitated with 21% and 100% oxygen.</a> Pediatr. Res. 59, 636-640 (2006).</li><li>Martin-Ancel, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multiple+organ+involvement+in+perinatal+asphyxia.">Multiple organ involvement in perinatal asphyxia.</a> J. Pediatr. 127, 786-793 (1995).</li><li>Swindle, M. M., Smith, A. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparative+anatomy+and+physiology+of+the+pig.">Comparative anatomy and physiology of the pig.</a> Scan. J. Lab. Anim. Sci. Suppl. 25, 11-22 (1998).</li><li>Chapados, I., Cheung, P. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Not+all+models+are+created+equal:+Animal+models+to+study+hypoxic-ischemic+encephalopathy+of+the+newborn.">Not all models are created equal: Animal models to study hypoxic-ischemic encephalopathy of the newborn.</a> Neonatology. 94, 300-303 (2008).</li><li>Liu, J. Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+post-resuscitation+treatment+with+N-acetylcysteine+on+cardiac+recovery+in+hypoxia-injured+newborn+pigs.">Effects of post-resuscitation treatment with N-acetylcysteine on cardiac recovery in hypoxia-injured newborn pigs.</a> PLoS ONE. 5, e15322-e15322 (2010).</li><li>Cheung, P. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardio-renal+recovery+of+hypoxic+newborn+pigs+after+18%,+21%+and+100%+reoxygenation.">Cardio-renal recovery of hypoxic newborn pigs after 18%, 21% and 100% reoxygenation.</a> Intensive Care Med. 34, 1114-1121 (2008).</li><li>Temesvari, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modulation+of+the+blood-brain+barrier+permeability+in+neonatal+cytotoxic+brain+edema:+laboratory+and+morphological+findings+obtained+on+newborn+piglets+with+experimental+pneumothorax.">Modulation of the blood-brain barrier permeability in neonatal cytotoxic brain edema: laboratory and morphological findings obtained on newborn piglets with experimental pneumothorax.</a> Biol. Neonate. 46, 198-208 (1984).</li><li>Domoki, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reventilation+with+room+air+or+100%+oxygen+after+asphyxia+differentially+affects+cerebral+neuropathology+in+newborn+pigs.">Reventilation with room air or 100% oxygen after asphyxia differentially affects cerebral neuropathology in newborn pigs.</a> Acta. Paediatr. 95, 1109-1115 (2006).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Part+15:+Neonatal+resuscitation:+2010+American+Heart+Association+guidelines+for+cardiopulmonary+resuscitation+and+emergency+cardiovascular+care.">Part 15: Neonatal resuscitation: 2010 American Heart Association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care.</a> Circulation. 122, S909-S919 (2010).</li></ol>

Çıkar çatışması ilan etti.

Güncel deneysel protokol hipoksi ve reoksijenasyon sürecinde yenidoğan olgularda sistemik ve bölgesel hemodinamik değişiklikleri incelemek için bir avantaja sahiptir. Ayrıca kurtarma sırasında kardiyovasküler fonksiyon geliştirmek için kullanılan müdahalelerin ilgili etkisini incelemek olabilir. Biz ve diğerleri kardiyovasküler 1, pulmoner 2, nörolojik 3, gastrointestinal 4, hepatik 5, böbrek 6, adrenal 7 ve hematolojik ...

a swine model of neonatal asphyxia

Asfiksi ile ilgili olarak Yıllık fazla 1 milyon daha yenidoğanlarda çapında ölür. Asfiksili yenidoğanlarda sık hipotansiyon, perfüzyon açığı, hipoksik-iskemik ensefalopati, pulmoner hipertansiyon, vasculopathic enterokolit, böbrek yetmezliği ve tromboembolik komplikasyonlar da dahil olmak üzere çoklu organ yetmezliği var. Hayvan modelleri bize pato-fizyolojisi ve neonatal asfiksi farmakolojisi anlamalarına yardımcı olmak için geliştirilmiştir. Kemirgenler ve yeni doğan kuzuların karşılaştırıldığında, yenidoğan yavrusu değerli bir model olmak için kanıtlanmıştır. Yenidoğan yavrusu 36-38 hafta olduğu gibi benzer bir gelişme de dahil olmak üzere birçok avantajı vardır hayvanın enstrümantasyon ve izleme sağlar ve karıştırıcı değişkenlerin kontrol karşılaştırılabilir vücut sistemleri, büyük vücut büyüklüğü (doğumda ~ 1.5-2 kg) ile insan fetusu hipoksi ve Hemodinamik bozukluklar. Biz burada neonatal asfiksi taklit ve bize syste incelemek için izin vermek için deneysel protokol açıklarmikrofon ve boğucu ve reoksijenasyon sürecinin yanı sıra müdahalelerin ilgili etkileri sırasında bölgesel hemodinamik değişiklikler. Bundan başka, model aynı anda çoklu-organ bozukluğu ya da fonksiyon bozukluğu okuyan avantaj ve çeşitli vücut sistemine sahip olan bir etkileşim içindedir. Deneysel model mekanik ventilasyon, vasküler (arteriyel ve santral venöz) erişim kurulmasına izin yenidoğan domuz yavrusu cerrahi enstrümantasyon (1-3, gündüz-eski ve 1.5-2.5 kg ağırlık melez) içerir olmayan bir sağkalım işlemdir ve ana pulmoner, karotis, superior mezenterik ve sol renal arterlerde olmak üzere farklı arterler boyunca intra-vasküler basıncı ve kan akışının sürekli izlenmesi için kateterler ve akış sondaları (Transonik A.Ş.) yerleştirme. Hemodinamik parametreler ve normal kan gazları Z &lt;% 10 varyasyonu ile tanımlanan 30-60 dakikalık stabilizasyon sonra, bu cerrahi enstrümante domuz kullanarak, deneysel protokol commenceşiddetli hipoksi hangi normocapnic alveolar hipoksi vasıtasıyla meydana gelir. Piglet% 30-40 arteryel oksijen saturasyonu hedefleyen, 2 saat boyunca azot gazı inhale konsantrasyonunu artırarak% 10-15 oranında oksijen ile ventile edilir. Hipoksemi Bu derece ağır metabolik asidoz, sistemik hipotansiyon ve hayati organlara hipoperfüzyon ile kardiyojenik şok ile klinik asfiksi üretecek. Hipoksi, 0.5H için% 100 oksijen ve daha sonra 3.5 saat için% 21 oksijen ile reoksijenasyonun tarafından takip edilir. Farmakolojik girişimler nedeniyle ders yılında tanıtılan ve etkileri bir kör, blok-randomize incelenebilir.

Watch this Scientific Journal Video about A Swine Model of Neonatal Asphyxia at JoVE.com

A Swine Model of Neonatal Asphyxia

Büyük hayvan modellerinde neonatal asfiksi fizyoloji ve farmakoloji sınavında iyi translasyonel değerlere sahiptir. Yenidoğan domuz kullanarak, sistemik ve bölgesel hemodinami, biyokimyasal ve patolojik yollar ve korelasyon ile oksijen taşınması eğitim avantajlarına sahip neonatal asfiksi taklit etmek için bir deney protokolü geliştirmektir.

Yenidoğan Asfiksi Bir Domuz Modeli

Annually more than 1 million neonates die worldwide as related to asphyxia. Asphyxiated neonates commonly have multi-organ failure including hypotension, ...

Research

JoVE Journal

Medicine

14.2K Görüntüleme.  University of Alberta. Büyük hayvan modellerinde neonatal asfiksi fizyoloji ve farmakoloji sınavında iyi translasyonel değerlere sahiptir. Yenidoğan domuz kullanarak, sistemik ve bölgesel hemodinami, biyokimyasal ve patolojik yollar ve korelasyon ile oksijen taşınması eğitim avantajlarına sahip neonatal asfiksi taklit etmek için bir deney protokolü geliştirmektir.

Video: A Swine Model of Neonatal Asphyxia

A Piglet Model of Neonatal Hypoxic-Ischemic Encephalopathy

Birth asphyxia, which causes hypoxic-ischemic encephalopathy (HIE), accounts for 0.66 million deaths worldwide each year, about a quarter of the world&#8217;s 2.9 million neonatal deaths. Animal models of HIE have contributed to the understanding of the pathophysiology in HIE, and have highlighted the dynamic process that occur in brain injury due to perinatal asphyxia. Thus, animal studies have suggested a time-window for post-insult treatment strategies. Hypothermia has been tested as a treatment for HIE in pdiglet models and subsequently proven effective in clinical trials. Variations of the model have been applied in the study of adjunctive neuroprotective methods and piglet studies of xenon and melatonin have led to clinical phase I and II trials1,2. The piglet HIE model is further used for neonatal resuscitation- and hemodynamic studies as well as in investigations of cerebral hypoxia on a cellular level. However, it is a technically challenging model and variations in the protocol may result in either too mild or too severe brain injury. In this article, we demonstrate the technical procedures necessary for establishing a stable piglet model of neonatal HIE. First, the newborn piglet (&#60; 24 hr old, median weight 1500 g) is anesthetized, intubated, and monitored in a setup comparable to that found in a neonatal intensive care unit. Global hypoxia-ischemia is induced by lowering the inspiratory oxygen fraction to achieve global hypoxia, ischemia through hypotension and a flat trace amplitude integrated EEG (aEEG) indicative of cerebral hypoxia. Survival is promoted by adjusting oxygenation according to the aEEG response and blood pressure. Brain injury is quantified by histopathology and magnetic resonance imaging after 72 hr.

Hypoxic-ischemic encephalopathy following perinatal asphyxia can be studied using animal models. We demonstrate the procedures necessary for establishing a piglet model of neonatal hypoxic-ischemic encephalopathy.

Yenidoğan Hipoksik-İskemik Ensefalopati A Piglet Modeli

Birth asphyxia, which causes hypoxic-ischemic encephalopathy (HIE), accounts for 0.66 million deaths worldwide each year, about a quarter of the ...

Tıp

A Neonatal Mouse Spinal Cord Compression Injury Model

Spinal cord injury (SCI) typically causes devastating neurological deficits, particularly through damage to fibers descending from the brain to the spinal cord. A major current area of research is focused on the mechanisms of adaptive plasticity that underlie spontaneous or induced functional recovery following SCI. Spontaneous functional recovery is reported to be greater early in life, raising interesting questions about how adaptive plasticity changes as the spinal cord develops. To facilitate investigation of this dynamic, we have developed a SCI model in the neonatal mouse. The model has relevance for pediatric SCI, which is too little studied. Because neural plasticity in the adult involves some of the same mechanisms as neural plasticity in early life1, this model may potentially have some relevance also for adult SCI. Here we describe the entire procedure for generating a reproducible spinal cord compression (SCC) injury in the neonatal mouse as early as postnatal (P) day 1. SCC is achieved by performing a laminectomy at a given spinal level (here described at thoracic levels 9-11) and then using a modified Yasargil aneurysm mini-clip to rapidly compress and decompress the spinal cord. As previously described, the injured neonatal mice can be tested for behavioral deficits or sacrificed for ex vivo physiological analysis of synaptic connectivity using electrophysiological and high-throughput optical recording techniques1. Earlier and ongoing studies using behavioral and physiological assessment have demonstrated a dramatic, acute impairment of hindlimb motility followed by a complete functional recovery within 2 weeks, and the first evidence of changes in functional circuitry at the level of identified descending synaptic connections1.

This article describes a method for generating a reproducible spinal cord compression injury (SCI) in the neonatal mouse. The model provides an advantageous platform for studying mechanisms of adaptive plasticity that underlie spontaneous functional recovery.

Bir Yenidoğan Fare Omurilik Sıkıştırma Yaralanması Modeli

Spinal cord injury (SCI) typically causes devastating neurological deficits, particularly through damage to fibers descending from the brain to the spinal ...

Myocardial Infarction in Neonatal Mice, A Model of Cardiac Regeneration

Myocardial infarction induced by coronary artery ligation has been used in many animal models as a tool to study the mechanisms of cardiac repair and regeneration, and to define new targets for therapeutics. For decades, models of complete heart regeneration existed in amphibians and fish, but a mammalian counterpart was not available. The recent discovery of a postnatal window during which mice possess regenerative capabilities has led to the establishment of a mammalian model of cardiac regeneration. A surgical model of mammalian cardiac regeneration in the neonatal mouse is presented herein. Briefly, postnatal day 1 (P1) mice are anesthetized by isoflurane and placed on an ice pad to induce hypothermia. After the chest is opened, and the left anterior descending coronary artery (LAD) is visualized, a suture is placed around the LAD to inflict myocardial ischemia in the left ventricle. The surgical procedure takes 10-15 min. Visualizing the coronary artery is crucial for accurate suture placement and reproducibility. Myocardial infarction and cardiac dysfunction are confirmed by triphenyl-tetrazolium chloride (TTC) staining and echocardiography, respectively. Complete regeneration 21 days post myocardial infarction is verified by histology. This protocol can be used to as a tool to elucidate mechanisms of mammalian cardiac regeneration after myocardial infarction.

This protocol describes a highly reproducible model of cardiac regeneration by surgical induction of myocardial infarction in the left ventricle of postnatal day 1 mice. The method involves induction of hypothermic anesthesia and ligation of the left anterior descending coronary artery.

Yenidoğan Farelerde Miyokard Enfarktüsü, Kalp Rejenerasyon Bir Model

Myocardial infarction induced by coronary artery ligation has been used in many animal models as a tool to study the mechanisms of cardiac repair and ...

A Chronic Cardiac Ischemia Model in Swine Using an Ameroid Constrictor

Cardiovascular disease remains the number one cause of mortality in the United States. There are numerous approaches to treating these diseases, but regardless of the approach, an in vivo model is needed to test each treatment. The pig is one of the most used large animal models for cardiovascular disease. Its heart is very similar in anatomy and function to that of a human. The ameroid placement technique creates an ischemic area of the heart, which has many useful applications in studying myocardial infarction. This model has been used for surgical research, pharmaceutical studies, imaging techniques, and cell therapies.
There are several ways of inducing an ischemic area in the heart. Each has its advantages and disadvantages, but the placement of an ameroid constrictor remains the most widely used technique. The main advantages to using the ameroid are its prevalence in existing research, its availability in various sizes to accommodate the anatomy and size of the vessel to be constricted, the surgery is a relatively simple procedure, and the post-operative monitoring is minimal, since there are no external devices to maintain. This paper provides a detailed overview of the proper technique for the placement of the ameroid constrictor.

The purpose of this protocol is to demonstrate the placement of a delayed constricting device (an ameroid constrictor) around a coronary artery in a swine model. This device creates an ischemic area of the heart that is useful for studying new diagnostic imaging techniques and new methods of treatment.

Bir Ameroid yılanı kullanarak domuz kronik kalp iskemi modelinde

Cardiovascular disease remains the number one cause of mortality in the United States. There are numerous approaches to treating these diseases, but ...

Tachycardia-Induced Cardiomyopathy As a Chronic Heart Failure Model in Swine

A stable and reliable model of chronic heart failure is required for many experiments to understand hemodynamics or to test effects of new treatment methods. Here, we present such a model by tachycardia-induced cardiomyopathy, which can be produced by rapid cardiac pacing in swine.
A single pacing lead is introduced transvenously into fully anaesthetized healthy swine, to the apex of the right ventricle, and fixated. Its other end is then tunneled dorsally to the paravertebral region. There, it is connected to an in-house modified heart pacemaker unit that is then implanted in a subcutaneous pocket. 
After 4 - 8 weeks of rapid ventricular pacing at rates of 200 - 240 beats/min, physical examination revealed signs of severe heart failure - tachypnea, spontaneous sinus tachycardia, and fatigue. Echocardiography and X-ray showed dilation of all heart chambers, effusions, and severe systolic dysfunction. These findings correspond well to decompensated dilated cardiomyopathy and are also preserved after the cessation of pacing.
This model of tachycardia-induced cardiomyopathy can be used for studying the pathophysiology of progressive chronic heart failure, especially hemodynamic changes caused by new treatment modalities like mechanical circulatory supports. This methodology is easy to perform and the results are robust and reproducible.

Here, we present a protocol to produce tachycardia-induced cardiomyopathy in swine. This model represents a potent way to study the hemodynamics of progressive chronic heart failure and the effects of applied treatment.

Kronik kalp yetmezliği model domuz olarak taşikardi kaynaklı kardiyomiyopati

A stable and reliable model of chronic heart failure is required for many experiments to understand hemodynamics or to test effects of new treatment ...

Severe Burn Injury in a Swine Model for Clinical Dressing Assessment

Wound healing is a dynamic repair process and is the most complex biological process in human life. In response to burn injury, alterations in biological pathways impair the inflammation response, resulting in delayed wound healing. Impaired wound healing frequently occurs in patients with diabetes leading to unfavorable outcomes such as amputation. Hence, dressings having beneficial effect in promoting burn wound repair are needed. However, studies on burn wound treatment are limited due to lack of proper animal models. Our previous study demonstrated wound-healing performance in rat and swine models using a minimally invasive surgical technique. This study aimed to demonstrate a swine model of severe burn injury that eliminates wound contraction and more closely approximates the human processes of re-epithelialization and new tissue formation. This protocol provides a detailed procedure for creating consistent burn wounds and examining the wound-healing performance under the treatment of an experimental dressing in a swine model. Six burn wounds were created symmetrically on the dorsum, which were covered with a clinical dressing composed of four layers: an inner contact layer of experimental materials, an inner intermediate layer of waterproof film, an outer intermediate layer of gauze, and an outer layer of adhesive plaster. Upon the completion of experiments, wound closure, wound area, and Vancouver Scar Scale score were examined. The samples of skin resected from each animal post-sacrifice were histologically prepared and stained using hematoxylin and eosin staining. Antibacterial activity of each dressing in the context of wound healing was also examined. The application of the clinical dressing to the wounds in swine model mimics the biological processes of human wound healing with respect to the processes of epithelialization, cellular proliferation, and angiogenesis. Therefore, this swine model provides an easy-to-learn, cost-effective, and robust method to assess the effect of clinical dressings in severe burn injury.

To closely mimic the mode of burn injuries requires the interplay between clinical observation and studies in animal models. In this study, a swine model of severe burn injury was established to assess an experimental dressing in physiological and pathophysiological settings.

Klinik soyunma değerlendirmesi için bir domuz modelinde şiddetli yanık yaralanma

Wound healing is a dynamic repair process and is the most complex biological process in human life. In response to burn injury, alterations in biological ...

Isometric Contractility Measurement of the Mouse Mesenteric Artery Using Wire Myography

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and drugs. It is widely used in many studies on the physiological functions of vascular smooth muscle, the pathogenesis of vascular diseases such as hypertension, and the development of smooth muscle relaxant drugs. The mouse is a widely used model animal with a large pool of disease models and genetically modified strains. We introduced this method to measure the isometric contraction of mouse mesenteric artery in detail. A 1.4-mm segment of mouse mesenteric resistance artery was isolated and mounted on a myograph chamber by passing two steel wires through its lumen. After equilibration and normalization steps, the vessel segment was potentiated by a high-K+ solution twice prior to the contraction assay. As an example of the application of this method in drug development, we measured the relaxant effect of a novel natural substance, neoliensinine, isolated from a Chinese herb, embryos of the lotus seed (Nelumbo nucifera Gaertn.) on mouse mesenteric arteries. The vessel segments mounted on the myograph chamber were stimulated with a high-K+ solution. When the force tension reached a stable sustained phase, cumulative doses of neoliensinine were added to the chamber. We found that neoliensinine had a dose-dependent relaxant effect on smooth muscle contraction, thus suggesting that it bears potential activity against hypertension. In addition, as the vessel segment can survive at least 4 hours after mounting and maintain contractility induced by the high-K+ solution for many times, we suggest that the wire myograph system may be used for the time-consuming process of drug screening.

The wire myograph technique is used to investigate vascular smooth muscle functions and screen new drugs. We report a detailed protocol for measuring the isometric contractility of the mouse mesenteric artery and for screening new relaxants of vascular smooth muscle.

İzometrik Contractility ölçüm tel Myography kullanarak fare mezenterik arter

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and ...

Establishing a Swine Model of Post-myocardial Infarction Heart Failure for Stem Cell Treatment

Although advances have been achieved in the treatment of heart failure (HF) following myocardial infarction (MI), HF following MI remains one of the major causes of mortality and morbidity around the world. Cell-based therapies for cardiac repair and improvement of left ventricular function after MI have attracted considerable attention. Accordingly, the safety and efficacy of these cell transplantations should be tested in a preclinical large animal model of HF prior to clinical use. Pigs are widely used for cardiovascular disease research due to their similarity to humans in terms of heart size and coronary anatomy. Therefore, we sought to present an effective protocol for the establishment of a porcine chronic HF model using closed-chest coronary balloon occlusion of the left circumflex artery (LCX), followed by rapid ventricular pacing induced with pacemaker implantation. Eight weeks later, the stem cells were administered by intramyocardial injection in the peri-infarct area. Then the infarct size, cell survival, and left ventricular function (including echocardiography, hemodynamic parameters, and electrophysiology) were evaluated. This study helps establish a stable preclinical large animal HF model for stem cell treatment.

We sought to establish a swine model of heart failure induced by left circumflex artery blockage and rapid pacing to test the effect and safety of intramyocardial administration of stem cells for cell-based therapies.

Kök Hücre Tedavisi Için Post-miyokard Enfarktüsü Kalp Yetmezliği Domuz Modeli Oluşturma

Although advances have been achieved in the treatment of heart failure (HF) following myocardial infarction (MI), HF following MI remains one of the major ...

Myocardial Infarction by Percutaneous Embolization Coil Deployment in a Swine Model

Myocardial infarction (MI) is the leading cause of mortality worldwide. Despite the use of evidence-based treatments, including coronary revascularization and cardiovascular drugs, a significant proportion of patients develop pathological left-ventricular remodeling and progressive heart failure following MI. Therefore, new therapeutic options, such as cellular and gene therapies, among others, have been developed to repair and regenerate injured myocardium. In this context, animal models of MI are crucial in exploring the safety and efficacy of these experimental therapies before clinical translation. Large animal models such as swine are preferred over smaller ones due to the high similarity of swine and human hearts in terms of coronary artery anatomy, cardiac kinetics, and the post-MI healing process. Here, we aimed to describe an MI model in pig by permanent coil deployment. Briefly, it comprises a percutaneous selective coronary artery cannulation through retrograde femoral access. Following coronary angiography, the coil is deployed at the target branch under fluoroscopic guidance. Finally, complete occlusion is confirmed by repeated coronary angiography. This approach is feasible, highly reproducible, and emulates the pathogenesis of human non-revascularized MI, avoiding the traditional open-chest surgery and the subsequent postoperative inflammation. Depending on the time of follow-up, the technique is suitable for acute, sub-acute, or chronic MI models.

Myocardial infarction (MI) animal models that emulate the natural process of the disease in humans are crucial to understanding pathophysiological mechanisms and testing the safety and efficacy of new emergent therapies. Here, we describe an MI swine model created by deploying a percutaneous embolization coil.

Bir Domuz Modelinde Perkütan Embolizasyon Bobini Dağıtımı ile Miyokard Enfarktüsü

Myocardial infarction (MI) is the leading cause of mortality worldwide. Despite the use of evidence-based treatments, including coronary revascularization ...

A Neonatal BALB/c Mouse Model of Necrotizing Enterocolitis

Necrotizing enterocolitis (NEC) is the most severe gastrointestinal (GI) disease that often occurs in premature infants, especially very low birth weight infants, with high mortality and unclear pathogenesis. The cause of NEC may be related to inflammatory immune regulatory system abnormalities. An NEC animal model is an indispensable tool for NEC disease immune research. NEC animal models usually use C57BL/6J neonatal mice; BALB/c neonatal mice are rarely used. Related studies have shown that when mice are infected, Th2 cell differentiation is predominant in BALB/c mice compared to C57BL/6J mice. Studies have suggested that the occurrence and development of NEC are associated with an increase in T helper type 2 (Th2) cells and are generally accompanied by infection. Therefore, this study used neonatal BALB/c mice to induce an NEC model with similar clinical characteristics and intestinal pathological changes as those observed in children with NEC. Further study is warranted to determine whether this animal model could be used to study Th2 cell responses in NEC.

Necrotizing enterocolitis (NEC) is the most severe gastrointestinal (GI) disease that often occurs in premature infants, especially very low birth weight infants, with high mortality and unclear pathogenesis. The cause of NEC may be related to inflammatory immune regulatory system abnormalities. An NEC animal model is an indispensable tool for NEC disease immune research. NEC animal models usually use C57BL/6J neonatal mice; BALB/c neonatal mice are rarely used. Related studies have shown that when mice are infected, Th2 cell differentiation is predominant in BALB/c mice compared to C57BL/6J mice. Studies have suggested that the occurrence and development of NEC are associated with an increase in T helper type 2 (Th2) cells and are generally accompanied by infection. Therefore, this study used neonatal BALB/c mice to induce an NEC model with similar clinical characteristics and intestinal pathological changes as those observed in children with NEC. Further study is warranted to determine whether this animal model could be used to study Th2 cell responses in NEC.

Nekrotizan Enterokolit'in Yenidoğan BALB/c Fare Modeli

Necrotizing enterocolitis (NEC) is the most severe gastrointestinal (GI) disease that often occurs in premature infants, especially very low birth weight ...