所有议定书均已由纽约州立大学布法罗 IACUC 机构动物保育和使用委员会批准。图 1显示了描述入侵和非侵入性监测的方法的说明。
1. 动物
<ol><li>使用时间日期, Q 发烧阴性, 怀孕母羊 (混合品种, 萨福克赛特-卡塔丁山品种) 与胎儿羔羊在127–143天怀孕。 注: 绵羊足月妊娠期为145天, 127 只怀孕羔羊表现得像极端早产儿。</li>
</ol>2. 手术前准备
<ol><li>在手术前从母羊那里扣留食物12小时。</li>
	<li>用静脉注射 (IV) 安定 (0.25–1.5 毫克/千克) 和氯胺酮 (4 毫克/千克) 使母羊镇静。</li>
	<li>引导母羊入侧卧床到升降推车上。</li>
	<li>将母羊移至背卧床上至 V 型手术台上。</li>
</ol>3. 麻醉
注: 在剖宫产前, 母羊以安定、氯胺酮和插管为镇静剂, 随后连续吸入异氟醚 (1–4%)。麻醉的充分性是通过评估肌肉的语调和眼睛的反射, 以及持续监测血氧水平的脉搏脉搏和心率来监测的。在检测过程中, 羔羊将受到产妇麻醉的影响, 并将接受局部麻醉, 以检测现场。
<ol><li>
将母羊插管10.0 毫米的气管导管 (ETT)。ETT 通过声带超过袖口的声音。充气 ETT 袖口, 并绑在 ETT 周围的母羊的下巴, 以确保它到位。
	<ol>
<li>当眼睑反应缺席时, 调整异氟醚 (2–3% 通常是足够的)。</li>
		<li>提供人工呼吸的常规机械通气 (CMV) 与一小部分的灵感氧 (不负担装卸2) 的0.21。设置呼吸机提供10–15毫升/千克的潮汐量。</li>
		<li>在母羊舌头上的脉冲脉搏连续监测 oxyhemoglobin 饱和度。</li>
		<li>用 capnograph 测量最终潮汐二氧化碳 (EtCO2)。</li>
		<li>调整不负担装卸2和巨细胞病毒, 以维持 oxyhemoglobin 饱和之间的 90-97% 和呼出 CO2之间的35–45毫米汞, 分别。</li>
	</ol>
</li>
	<li>
将母羊的四肢固定在手术台上, 并进行外科治疗。
	<ol>
<li>调整手术表, 扭转向健位置, 减轻胎儿压力。</li>
	</ol>
</li>
	<li>放置一个 orogastric 管减压和排泄胃的内容。</li>
	<li>补充 IV 液体 (正常生理盐水或乳酸枪手溶液) 在10毫升/千克/小时。</li>
	<li>放置一个直肠温度探头, 以获得连续的核心温度。</li>
</ol>4. 手术
注: 剖宫产和胎儿程序被认为是急性手术, 其中动物通过管理戊巴比妥钠100毫克/千克 iv。母羊在羔羊分娩后被安乐死, 在实验完成后, 羔羊被安乐死。停搏证实了安乐死。另外还采用了双侧开胸或放血的辅助方法。在这种情况下, 无菌技术在手术期间没有被实践。在动物接触期间, 人员仍需佩戴防护服。
<ol><li>把腹部的羊毛剃掉。</li>
	<li>
使用烧灼做一个 15–18 cm 腹部皮肤深切口在 linea 的阿尔多暴露的筋膜。
	<ol>
<li>用钝尖的止血的压力创建一个小开口入腹部。</li>
		<li>保持这个开放, 而滑动钝的尖剪刀到腹壁。</li>
		<li>用剪刀完成 linea 的切口。</li>
	</ol>
</li>
	<li>
从腹部定位并 exteriorize 子宫内的胎儿头部。
	<ol>
<li>用一只手握住胎儿的头, 用烧灼在子宫壁 (在羔羊额头上) 做一个10厘米的切口。确保避免任何子叶。</li>
		<li>使用 "用" 钳夹住子宫和胎盘的层, 在四个对立的角落。</li>
		<li>通过子宫和母羊的腹部外暴露羔羊的头部。</li>
		<li>在胎儿手术期间, 将在腹部外放置的一只钳子钳留下。</li>
	</ol>
</li>
</ol>5. 胎气道
<ol><li>
用3.5–4.5 毫米袖口 ETT 插管部分裸露的胎儿羔羊。通过声带1厘米以上的 ETT 向前推进。
	<ol>
<li>充气袖口和安全的 ETT 通过绑在管周围的脐带胶带, 然后围绕头部。</li>
		<li>在 ETT 中允许过量的胎儿肺液通过将头部倾斜到一侧而被动排出。这模拟在分娩过程中肺液体的出口。</li>
		<li>咬合在窒息期间, ETT 防止气体交换。</li>
	</ol>
</li>
</ol>6. 颈部容器仪表
<ol><li>
在所有切口部位剃羊毛并渗入皮下盐酸布比卡因 (0.25%)。
	<ol>
<li>将两个3厘米的皮肤切口在颈部的两侧 (大约6厘米的头部远端) 与气管相邻。切口应横颈。</li>
		<li>tenting 皮肤时, 用烧灼进行切口, 避免划破深层组织。</li>
	</ol>
</li>
	<li>用弯曲的凯利或蚊子钳分隔筋膜。</li>
	<li>
隔离右颈内静脉和右颈总动脉。
	<ol>
<li>在两条船下放置两个20厘米, 0 丝缝线。</li>
		<li>在丝缝线之间允许 (近至远端) 1 厘米的空间。</li>
		<li>轻轻地提起每条围绕血管的缝合线, 表面上, 以限制血液流动, 并使一个用虹膜外科剪刀切割到血管中的一毫米。</li>
	</ol>
</li>
	<li>
在颈动脉, 插入一个预冲洗导管 (15–17 G) 在右颈动脉 caudally 向主动脉弓的血压监测和血液取样。
	<ol>
<li>使用近端领带完全结扎动脉。</li>
		<li>重复步骤 6.3.2-6.3.3。</li>
		<li>插入预冲洗的颈动脉导管, 用远端丝缝线将动脉和导管围成3节。</li>
	</ol>
</li>
	<li>使用类似的技术, 将一个预冲洗导管 (14–16 G) 插入颈静脉, 重复步骤 6.3. 2–6.3 3, 提前7–10厘米 caudally 在胸腔入口 (朝向右心房) 休息。这是用于液体和药物管理以及静脉压力测量。<ol>
<li>检查导管的通畅与血气生理盐水, 然后完成缝合领带周围的血管和导管 (仅近缝合) 使用2–3结。</li>
		<li>插入第二导管 (14–16 G) 约5厘米 rostrally 收集血液从脑循环。使用相同的切口放置两个导管。</li>
		<li>重复步骤 6.5.1, 因为它涉及到远端缝合和导管, 然后绑在对方导管线周围的丝缝线, 以确保他们到位, 以防止扭曲。</li>
	</ol>
</li>
	<li>
将先前做过的切口延伸到左侧的 T 形 (一厘米)。
	<ol>
<li>用开曲止血剂抬高左颈动脉。</li>
		<li>在血管周围放置一个2毫米周围流探针来测量血流。</li>
		<li>用1厘米的挠性聚合物套筒覆盖流探针, 以稳定探头的位置。</li>
		<li>将流探针电缆线放入 T 形切口, 使电缆与容器平行运行。</li>
		<li>关闭皮肤切口。绑在电缆周围, 绕着一圈电缆, 以避免限制流量, 如果拉。</li>
	</ol>
</li>
</ol>7. 大容器仪表
<ol><li>提取胎儿羔羊露出胸部, 并覆盖裸露的皮肤与聚乙烯包装, 以防止热损失。</li>
	<li>把羔羊放在右外侧卧床。</li>
	<li>将左前肢放置在颈部, 以暴露手术部位。</li>
	<li>
渗透3毫升盐酸布比卡因 (0.25%) 沿4次肋间空间和做一个6厘米皮肤切口使用烧灼。
	<ol>
<li>小心刺穿肋间肌肉与钝弯曲钳, 圆在 3路肋骨之下, 并且出来在下肋骨空间之间。确保不要伤害肺部或心脏。</li>
		<li>为0丝的预切件打开夹具, 并将其穿过以包围肋骨。</li>
		<li>重复步骤 7.4. 1–7.4 2, 以确保在4次肋骨下缝合。</li>
		<li>夹紧每个肋骨周围的领带。轻轻拉起, 并插入一个棉尖的涂抹器进入胸部4次肋间空间。</li>
		<li>使用涂抹杆来保护胸部内容, 同时使用烧灼打开1厘米的肋间空间, 为最终开放 6-8 厘米. 确保肺不被夹在肋骨上。</li>
		<li>把肋骨放在胸腔开口处。打开胸腔将显示左上叶的肺, 主肺动脉 (PA) 和动脉导管未闭。</li>
	</ol>
</li>
	<li>
使用 2 x 2 英寸纱布包络肺和轻轻推任何暴露的组织远离手术区。
	<ol>
<li>使用小型手动牵引器改善视野 (如有必要)。</li>
		<li>将脐带 (1/4 英寸宽, 6 英寸长) 预浸泡在羊膜周围的大血管。将脐带浸泡在血管壁上会减少摩擦 (和伤害)。</li>
	</ol>
</li>
	<li>使用镊子, 提起心包, 沿主肺动脉切开, 注意不要切断迷走神经。使用涂抹杆保持右心房不干预心包侧切口沿迷走神经。</li>
	<li>
使用双子钳, 从导管/pa 凹槽缓慢移动钳在左 pa 周围和后面的 "包围", 并出现在左 pa 的另一侧。许多微妙的组织在这个区域运行, 只有在没有抵抗的情况下才进行。
	<ol>
<li>当钳的尖端被观察到, 只打开足够远, 以抓住前湿润的脐带的一端。钳位, 只有1位置点击到位。可能, 周围的组织也可能被抓在钳, 如果紧紧夹住的组织可能会被捕获的脐带胶带导致血管损伤。</li>
		<li>轻轻地退下镊子把胶带拉到原位。这有助于为流探针打开一个空间, 并帮助引导流探针的插入 (图 2)。注意保护任何船只的缺口部分是必要的, 因为这是最脆弱的部分组织。</li>
	</ol>
</li>
	<li>
放置一个第4-6 毫米周围流探针, 轻轻地抬起脐带, 引导探针周围的探头 (L 括号) 金属部分沿已建立的开口。
	<ol>
<li>将胶带指向探头的背面, 以帮助放置容器, 并可视化 L 支架的末端, 从而使滑动闭合得到保护。</li>
		<li>确保该船的探头尺寸 > 75%, 以确保紧密配合和准确的流量测量。</li>
		<li>小心地切断靠近探头的脐带胶带的末端, 轻轻拉另一端从容器中取出胶带。如果不移除, 磁带将干扰测量。</li>
		<li>应用超声波凝胶, 调整探头和电缆位置, 提高信号强度和质量。</li>
	</ol>
</li>
	<li>重复步骤 7.6–7.7 4, 因为它涉及到放置一个 6-8 毫米周围流探针周围动脉导管未闭。</li>
	<li>从胸部取出任何保护性的 2 x 2 纱布, 让肺部重新定位。</li>
	<li>放置一个新的 2 x 2 纱布周围的每个金属托架的流量探头, 以保护肺部。</li>
	<li>用锥形针和2.0 合成单丝缝合在层中闭合胸部。使用切割针和2.0 丝缝线将流探针的电缆固定在外层皮肤上。</li>
</ol>8. 无创测量
<ol><li>在右腋窝、左腋窝和右腹股沟区域连接心电图引线 (三导心电图)。导管前动脉 oxyhemoglobin 饱和度 (2) 是用脉冲脉搏在右前肢和后肢分别监测。用缝线和不透明的敷料在前额上固定一个近红外光谱仪 (红外光谱) 监视器。</li>
</ol>9. 数据收集
<ol><li>使用数据采集软件收集和记录数据。图 1显示了侵入性和非侵入的参数, 包括: 动脉和中心静脉血压, 左颈总动脉, 左肺和导管动脉血流, 心电图,2,近红外光谱, ETCO2。 注意: 数据收集的软件和设备设置可能会有所不同, 超出了本文的范围。</li>
</ol>10. 试验性议定书
<ol><li>咬合并切断脐带, 将羔羊从母体腹部移至辐射温暖的部位。</li>
	<li>在窒息期, 插入脐静脉导管的肾上腺素管理 (0.01–0.03 毫克/千克 IV, 每 NRP 建议)。</li>
	<li>插入脐动脉导管收集导管后动脉血气。</li>
	<li>监测羔羊的临近停搏, 这可以定义为没有检测到颈动脉流量和压力。</li>
	<li>确保有足够的人员, 并把每个人都奉献给以下任务: (1) 管理通气和气道, (2) 进行胸外按压, (3) 用药, (4) 抽取血样, (5) 引导代码。</li>
	<li>开始复苏, 提供正压通气 (PPV) 与 T 片复苏器在压力35/5 厘米 H2o 启动20分钟计时器的实验性复苏协议。</li>
	<li>
在三十年代的通气后, 开始胸部按压通过放置拇指和手指的一只手在对面的胸部。
	<ol>
<li>通过将手指和拇指挤压到大约1/3 的深度来提供胸部按压。</li>
	</ol>
</li>
	<li>以3分钟的间隔管理肾上腺素。</li>
	<li>持续复苏的努力, 直到返回的自发循环或高达20分钟。</li>
	<li>在自发循环返回时, 连续 IV 流体 (5 毫升/千克/小时) 和芬太尼 (0.5-2.0 微克/千克/小时, 滴定), 是通过先前建立的颈静脉导管。在20分钟的复苏期后, 该动物被安乐死。如果羔羊不能达到 ROSC 20 分钟, 继续安乐死。</li>
</ol>

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B., 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=Cardiovascular+transition+at+birth:+a+physiological+sequence.">Cardiovascular transition at birth: a physiological sequence.</a> Pediatr Res. 77 (5), 608-614 (2015).</li><li>Vali, 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=Evaluation+of+Timing+and+Route+of+Epinephrine+in+a+Neonatal+Model+of+Asphyxial+Arrest.">Evaluation of Timing and Route of Epinephrine in a Neonatal Model of Asphyxial Arrest.</a> J Am Heart Assoc. 6 (2), (2017).</li><li>Vali, 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=Continuous+Chest+Compressions+During+Sustained+Inflations+in+a+Perinatal+Asphyxial+Cardiac+Arrest+Lamb+Model.">Continuous Chest Compressions During Sustained Inflations in a Perinatal Asphyxial Cardiac Arrest Lamb Model.</a> Pediatr Crit Care Med. , (2017).</li><li>Vali, 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=Hemodynamics+and+gas+exchange+during+chest+compressions+in+neonatal+resuscitation.">Hemodynamics and gas exchange during chest compressions in neonatal resuscitation.</a> PLoS One. 12 (4), e0176478 (2017).</li><li>Tana, M., 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=Determination+of+Lung+Volume+and+Hemodynamic+Changes+During+High-Frequency+Ventilation+Recruitment+in+Preterm+Neonates+With+Respiratory+Distress+Syndrome.">Determination of Lung Volume and Hemodynamic Changes During High-Frequency Ventilation Recruitment in Preterm Neonates With Respiratory Distress Syndrome.</a> Crit Care Med. 43 (8), 1685-1691 (2015).</li><li>Morin, F. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ligating+the+ductus+arteriosus+before+birth+causes+persistent+pulmonary+hypertension+in+the+newborn+lamb.">Ligating the ductus arteriosus before birth causes persistent pulmonary hypertension in the newborn lamb.</a> Pediatr Res. 25 (3), 245-250 (1989).</li><li>Morin, F. C., Egan, E. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pulmonary+hemodynamics+in+fetal+lambs+during+development+at+normal+and+increased+oxygen+tension.">Pulmonary hemodynamics in fetal lambs during development at normal and increased oxygen tension.</a> J Appl Physiol (1985). 73 (1), 213-218 (1992).</li><li>Morin, F. C., Egan, E. A., Ferguson, W., Lundgren, C. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+pulmonary+vascular+response+to+oxygen.">Development of pulmonary vascular response to oxygen.</a> Am J Physiol. 254 (3 Pt 2), H542-H546 (1988).</li><li>Rawat, M., 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=Neonatal+resuscitation+adhering+to+oxygen+saturation+guidelines+in+asphyxiated+lambs+with+meconium+aspiration.">Neonatal resuscitation adhering to oxygen saturation guidelines in asphyxiated lambs with meconium aspiration.</a> Pediatr Res. , (2015).</li><li>Chandrasekharan, P. K., 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=Continuous+End-Tidal+Carbon+Dioxide+Monitoring+during+Resuscitation+of+Asphyxiated+Term+Lambs.">Continuous End-Tidal Carbon Dioxide Monitoring during Resuscitation of Asphyxiated Term Lambs.</a> Neonatology. 109 (4), 265-273 (2016).</li><li>Lakshminrusimha, S., 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=Tracheal+suctioning+improves+gas+exchange+but+not+hemodynamics+in+asphyxiated+lambs+with+meconium+aspiration.">Tracheal suctioning improves gas exchange but not hemodynamics in asphyxiated lambs with meconium aspiration.</a> Pediatr Res. 77 (2), 347-355 (2015).</li><li>Meuli, M., 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=In+utero+surgery+rescues+neurological+function+at+birth+in+sheep+with+spina+bifida.">In utero surgery rescues neurological function at birth in sheep with spina bifida.</a> Nat Med. 1 (4), 342-347 (1995).</li><li>Meuli, M., 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=Creation+of+myelomeningocele+in+utero:+a+model+of+functional+damage+from+spinal+cord+exposure+in+fetal+sheep.">Creation of myelomeningocele in utero: a model of functional damage from spinal cord exposure in fetal sheep.</a> J Pediatr Surg. 30 (7), 1028-1032 (1995).</li><li>Adzick, N. 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Simulated correction permits fetal lung growth with survival at birth.</a> Surgery. 88 (2), 260-268 (1980).</li><li>Turley, K., 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=Intrauterine+cardiothoracic+surgery:+the+fetal+lamb+model.">Intrauterine cardiothoracic surgery: the fetal lamb model.</a> Ann Thorac Surg. 34 (4), 422-426 (1982).</li><li>Reddy, V. M., 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=In+utero+placement+of+aortopulmonary+shunts.+A+model+of+postnatal+pulmonary+hypertension+with+increased+pulmonary+blood+flow+in+lambs.">In utero placement of aortopulmonary shunts. A model of postnatal pulmonary hypertension with increased pulmonary blood flow in lambs.</a> Circulation. 92 (3), 606-613 (1995).</li><li>Hemway, R. J., Christman, C., Perlman, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+3:1+is+superior+to+a+15:2+ratio+in+a+newborn+manikin+model+in+terms+of+quality+of+chest+compressions+and+number+of+ventilations.">The 3:1 is superior to a 15:2 ratio in a newborn manikin model in terms of quality of chest compressions and number of ventilations.</a> Arch Dis Child Fetal Neonatal Ed. 98 (1), F42-F45 (2013).</li><li>Solev&#229;g, A. L., Schm&#246;lzer, G. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optimal+Chest+Compression+Rate+and+Compression+to+Ventilation+Ratio+in+Delivery+Room+Resuscitation:+Evidence+from+Newborn+Piglets+and+Neonatal+Manikins.">Optimal Chest Compression Rate and Compression to Ventilation Ratio in Delivery Room Resuscitation: Evidence from Newborn Piglets and Neonatal Manikins.</a> Frontiers in Pediatrics. 5 (3), (2017).</li><li>Solev&#229;g, A. 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=Chest+compressions+in+newborn+animal+models:+A+review.">Chest compressions in newborn animal models: A review.</a> Resuscitation. 96, 151-155 (2015).</li></ol>

作者没有利益冲突申报

羔羊模型是可比的大小, 以人类新生儿和允许简易仪器测量侵入性血流动力学变量。胎儿/新生羔羊模型是一个宝贵的研究工具, 丰富的帮助了解过渡循环, 以及新生儿的肺和心血管生理学。多年来建立了几个实验性羔羊模型, 研究了持续性肺动脉高压导管中早产儿13、14、21、肺血流动力学的最佳通气策略。结扎模型22,23,24, 肺血管反应性在胎粪吸入模型25,26,27, 以及胎儿的外科模型myelomeningocele28,29, 先天性膈疝30,31, 先天性心脏缺损32,33, 这一切都有相当大的影响临床管理。
在胎儿仪器中, 需要注意避免脐带上的任何压力, 因为这可能会对羔羊造成不必要的压力, 并会影响到羔羊的麻醉。流探针和导管需要小心地缝合到羔羊的皮肤, 以保护血管不受伤害, 如果疏忽牵引放置在导管上。手术器械的胎儿心脏构成了更大的风险, 破坏性并发症 (死亡放血), 除非精心执行。切口需要完全缝合在层数, 因为不完整的封印可能影响胸部压缩效率。在羔羊插管后, 肺液应通过将胎儿头部倾斜到侧面而被动排出。平均来说, 15-20 毫升/公斤的肺液可以被动排出。然后, 胎儿羔羊剩下的肺液接近于新生儿的估计肺液。ETT 需要在窒息前被脐带夹紧, 以防在喘气时进行气体交换。pulselessness 后5分钟的心跳骤停, 因为自发循环的返回, 否则, 在正压通气后迅速发生。由于胎儿基线动脉气体并没有表现出明显的酸中毒, 在实验前进行的胎儿器械似乎不会对羔羊造成相当大的压力。妊娠通常是在实验前确定的超声确认, 但也可以评估通过仔细检查的母羊在经验丰富的手。在多个胎儿的情况下, 每只羔羊依次进行检测。进行羔羊实验的一个重要考虑因素是成本的显著提高。
直到最近, 羔羊模型还没有被用来研究新生儿复苏。由于目前的 NRP 建议主要是从成人文学或假人34,35和产后动物模型36 , 并没有充分描述新生儿生理学的分娩室,本文所述的议定书表明, 围产儿窒息羔羊模型可为改善未充分向宫外孕环境过渡的新生儿复苏努力提供有希望的贡献。图 5显示了已成功复苏的新生羔羊的血压和流量。比较血压和流量 (这个模型的优势, 以测量动脉导管未闭的流量) 的实验评估不同的压缩到通气率和/或血管活性药物的模型, 过渡循环将提供更好地了解新生儿复苏过程中的血流动力学。这一模型的实验将提高对最佳胸部压缩比、定时和用药剂量的理解, 激发氧在新生儿复苏中的影响, 以及解决许多其他假说。

围产期窒息发生在大约4每1000足月出生在美国和负责大约 25% 400万新生儿死亡全世界1,2。在胎儿的自然发育过程中, 必须在分娩和分娩期间进行几种适应, 以便在肺部作为气体交换器官的作用下, 从内到宫外孕环境进行无缝过渡。新生儿在出生时没有充分过渡的任何失败进一步损害了复苏的努力。当胎儿肺间隙不完整或延迟3、4和导致持续性高肺血管阻力的情况下,5会影响通气效果, 这仍然是最重要干预在窒息新生儿的复苏6。此外, 立即夹脐带和去除低阻胎盘可能导致心脏输出突变, 可能导致心肌功能障碍7,8。
由于不经常需要积极的复苏 (胸部按压和/或肾上腺素管理需要)1,9, 缺乏强有力的证据从大型随机临床试验, 以支持目前新生儿复苏计划 (NRP) 指南。在新生儿复苏的许多翻译研究研究使用产后动物模型 (特别是仔猪), 无法充分描述过渡胎儿循环和液体填充肺部的新生儿在分娩房间。鉴于与胎儿循环向新生儿循环过渡有关的独特挑战, 围产期窒息心脏骤停胎儿羔羊模型是研究新生儿复苏生理学的理想方法。
约瑟夫来源对胎儿羔羊的研究, 早在1930代初, 奠定了胎儿和新生儿生理学的基础10。在20世纪的后半部分 , 杰弗里？道斯对胎儿羔羊模型进行了创新细致的实验, 后来亚伯拉罕. 鲁道夫对胎儿的心血管和肺生理学知识作出了巨大贡献。11,12. 近年来, 对胎儿/新生儿羔羊模型的研究提供了更好的了解通气对血流动力学的影响13,14, 氧合效应对以及在脐带钳夹7、17中发生的循环变化。最后, 在过去的一年中, 新生羔羊作为一种新的模型来研究复苏18,19,20的血流动力学效应。对进行羔羊实验所涉及的内容, 以及对外科仪器和实验方法的详细描述, 将提出一个循序渐进的叙述。

<table border="0" cellpadding="0" cellspacing="0" width="819">
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;">Babcock forceps</td>
			<td>Miltex</td>
			<td>16-44</td>
			<td style="width:200px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Blood pressure transducer</td>
			<td style="width:192px;">Becton Dickinson</td>
			<td style="width:211px;">P23XL-1</td>
			<td style="width:200px;">Used with saline filled diaphragm domes</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Blunt tipped scissors</td>
			<td style="width:192px;">Miltex</td>
			<td style="width:211px;">98SCS50-56</td>
			<td style="width:200px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Capnograph</td>
			<td style="width:192px;">Philips</td>
			<td style="width:211px;">7900</td>
			<td style="width:200px;">Used with Neonatal Flow Sensors</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Cautery pencil</td>
			<td style="width:192px;">Valley Lab</td>
			<td style="width:211px;">287879</td>
			<td style="width:200px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Cautery unit</td>
			<td style="width:192px;">Valley Lab</td>
			<td style="width:211px;">SSE2K</td>
			<td style="width:200px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Curved Forceps</td>
			<td style="width:192px;">Everost</td>
			<td style="width:211px;">711714</td>
			<td style="width:200px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Data acquisition software</td>
			<td style="width:192px;">Biopac Systems Inc.</td>
			<td style="width:211px;">ACK100W</td>
			<td style="width:200px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">EKG</td>
			<td style="width:192px;">Biopac Systems Inc.</td>
			<td style="width:211px;">ECG100C</td>
			<td style="width:200px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Endotracheal tube -cuffed</td>
			<td style="width:192px;">Rusch</td>
			<td style="width:211px;">111780035</td>
			<td style="width:200px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Flow modulator</td>
			<td style="width:192px;">Transonic Systems Inc.&#160;</td>
			<td style="width:211px;">T403</td>
			<td style="width:200px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Flow-probe</td>
			<td style="width:192px;">Transonic Systems Inc.&#160;</td>
			<td style="width:211px;">MC4PSS-LS-WC100-CM4B-GA</td>
			<td style="width:200px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Gastric tube</td>
			<td style="width:192px;">Jorgensen Labs Inc.</td>
			<td style="width:211px;">J0106LE</td>
			<td style="width:200px;">To decompress and drain ewe stomach</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Hair clipper</td>
			<td style="width:192px;">Andis Company</td>
			<td style="width:211px;">65340</td>
			<td style="width:200px;">&#160;# 40 Clipper Blade</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Infant radiant warmer</td>
			<td>GE healthcare</td>
			<td>7810</td>
			<td style="width:200px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Intravenous catheters</td>
			<td>Becton Dickinson</td>
			<td>381234</td>
			<td style="width:200px;"></td>
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		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Iris surgical scissors</td>
			<td style="width:192px;">Patterson</td>
			<td style="width:211px;">510585</td>
			<td style="width:200px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Kelly Foreceps</td>
			<td style="width:192px;">Patterson</td>
			<td style="width:211px;">510535</td>
			<td style="width:200px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Mosquito Forceps</td>
			<td style="width:192px;">RICA Surgical Products INC</td>
			<td style="width:211px;">1-74</td>
			<td style="width:200px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Near-infrared spectroscopy</td>
			<td style="width:192px;">Nonin Medical Inc.&#160;</td>
			<td style="width:211px;">X-100M</td>
			<td style="width:200px;">Sensmart Equanox &#38; PureSAT</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">RSO2 Sensor</td>
			<td style="width:192px;">Nonin Medical Inc.&#160;</td>
			<td style="width:211px;">8004CB-NA</td>
			<td style="width:200px;">Neonatal&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Scalpel handle and blade</td>
			<td style="width:192px;">Everost</td>
			<td>707203</td>
			<td style="width:200px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Sutures -silk 2-0</td>
			<td style="width:192px;">Covidien</td>
			<td style="width:211px;">SS-695</td>
			<td style="width:200px;">Used for tying catheters to vessels</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Sutures -vicryl&#160; 2-0</td>
			<td style="width:192px;">Ethicon</td>
			<td style="width:211px;">J269H</td>
			<td style="width:200px;">Used for closing thoracotomy&#160;</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">T-piece resuscitator</td>
			<td>Neo-Tee</td>
			<td>MCM1050812</td>
			<td style="width:200px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Umbilical ties</td>
			<td style="width:192px;">Jorgensen Labs Inc.</td>
			<td>J0025UA</td>
			<td style="width:200px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Weitlander Retractor</td>
			<td style="width:192px;">Miltex</td>
			<td style="width:211px;">11-625</td>
			<td style="width:200px;"></td>
		</tr>
	</tbody>
</table>

the perinatal asphyxiated lamb model: a model for newborn resuscitation

出生窒息每年在全世界造成近100万人死亡, 是新生儿早期发病率和死亡率的主要原因之一。目前新生儿复苏指南的许多方面仍然存在争议, 因为在进行随机临床试验方面存在困难, 因为需要进行广泛的复苏。大多数关于新生儿复苏的研究都来自于假人模型, 它们无法真正反映生理变化或仔猪模型, 清除了他们的肺液, 已经完成了从胎儿到新生儿循环的转变。本议定书提供了一个详细的分步说明如何创建围产期窒息胎儿羔羊模型。该模型有一个过渡循环和液体填充肺部, 模仿人类新生儿分娩后, 因此, 是一个良好的动物模型, 研究新生儿生理学。对羔羊实验的一个重要限制是较高的相关成本。

根据胎儿羔羊的检测, 可以记录血流动力学变量 (图 3和图 4), 然后进行分析和解释 (图 5)。可以收集频繁的血液样本,图 6显示了其中一个实验的 pH 值和帕2数据。有时, 导管或流探头可能会出现故障或脱落, 因此数据不能收集和用于分析, 如图 7所示。
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/57553/57553fig1.jpg"> 图 1: 在羔羊模型中侵入性和非侵入性仪器.插图描述侵入性仪器 (静脉和动脉导管插入的血液取样和压力监测以及血管流量探头放置的血液流量测量), 并安置非侵入设备 (脉冲脉搏,心电图导则, 近红外光谱, capnography)。<a href="/files/ftp_upload/57553/57553fig1large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/57553/57553fig2v3.jpg"> 图 2: 大血管隔离.结缔组织的温和分离创造了一个空间, 将湿脐放在血管周围 (a), 随后放置流动探头, 用于超声测量每条血管内的血流量 (B)。<a href="/files/ftp_upload/57553/57553fig2v2large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/57553/57553fig3.jpg"> 图 3: 采集软件快照捕获围产儿窒息羔羊血流动力学成功复苏.Ao 压力: 右颈动脉血压;钙流: 左颈动脉血流;血流: 左肺动脉血液流动。<a href="/files/ftp_upload/57553/57553fig3large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/57553/57553fig4.jpg"> 图 4: 采集软件快照, 描述侵袭性和非侵入性生理测量.Ao: 右颈动脉血压;CVP: 中心静脉压;左颈动脉血流;冠状动脉: 左降冠状动脉血流;左肺动脉血流;DuF: 动脉导管未闭血流;ETCO2: 末端潮汐 CO2;铅 2: 心电图导致2录音。<a href="/files/ftp_upload/57553/57553fig4large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<img alt="Figure 5" class="xfigimg" src="/files/ftp_upload/57553/57553fig5.jpg"> 图 5: 围产期窒息羔羊血流动力学成功复苏.血压、左颈动脉血流量和左肺血流量的变化显示在胸部按压 (A) 和反冲期 (B) 的压缩阶段。左肺和颈动脉血流在二次轴上绘制。CC: 胸部压迫;肾上腺素;肺动脉;ROSC: 自然循环的回归。<a href="/files/ftp_upload/57553/57553fig5large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<img alt="Figure 6" class="xfigimg" src="/files/ftp_upload/57553/57553fig6.jpg"> 图 6: 实验研究中的血气分析.虚线表示自发循环的返回时间。在次坐标轴上绘制了帕2 。<a href="/files/ftp_upload/57553/57553fig6large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<img alt="Figure 7" class="xfigimg" src="/files/ftp_upload/57553/57553fig7.jpg"> 图 7: 采集软件图片显示故障流探头.尽管有足够的血压 (红色追踪) 和左肺动脉血流 (紫色追踪), 但颈动脉血流量 (绿色追踪) 记录丢失。<a href="/files/ftp_upload/57553/57553fig7large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>

Watch this Scientific Journal Video about The Perinatal Asphyxiated Lamb Model: A Model for Newborn Resuscitation at JoVE.com

The Perinatal Asphyxiated Lamb Model: A Model for Newborn Resuscitation

侵入性仪器的胎儿羔羊提供准确的生理测量的过渡循环的模型, 密切模仿新生儿。

围产儿窒息羔羊模型: 新生儿复苏模型的建立

Birth asphyxia accounts for nearly one million deaths worldwide each year, and is one of the primary causes of early neonatal morbidity and mortality. ...

the-perinatal-asphyxiated-lamb-model-a-model-for-newborn-resuscitation

Nanyang Technological University

Research

JoVE Journal

Medicine

10.7K 次观看.  University of California Davis. 侵入性仪器的胎儿羔羊提供准确的生理测量的过渡循环的模型, 密切模仿新生儿。

视频: The Perinatal Asphyxiated Lamb Model: A Model for Newborn Resuscitation

Normothermic Cardiac Arrest and Cardiopulmonary Resuscitation: A Mouse Model of Ischemia-Reperfusion Injury

Acute Kidney Injury (AKI) is a common, highly lethal, complication of critical illness which has a high mortality1-4 and which is most 
frequently caused by whole-body hypoperfusion.5,6 Successful reproduction of whole-body hypoperfusion in rodent models has been fraught with 
difficulty.7-9,9,10 Models which employ focal ischemia have repeatedly demonstrated results which do not translate to the clinical setting, and larger 
animal models which allow for whole body hypoperfusion lack access to the full toolset of genetic manipulation possible in the mouse.11,12 However, in recent 
years a mouse model of cardiac arrest and cardiopulmonary resuscitation has emerged which can be adapted to model AKI.13 This model reliably reproduces 
physiologic, functional, anatomic, and histologic outcomes seen in clinical AKI, is rapidly repeatable, and offers all of the significant advantages of a murine surgical 
model, including access to genetic manipulative techniques, low cost relative to large animals, and ease of use. Our group has developed extensive experience 
with use of this model to assess a number of organ-specific outcomes in AKI.14,15

A powerful model for perioperative and critical care related acute kidney injury is presented. Using whole body hypoperfusion induced by cardiac arrest it is possible to nearly replicate the histologic and functional changes of clinical AKI.

常温心脏骤停和心肺复苏术:缺血再灌注损伤的小鼠模型

Acute Kidney Injury (AKI) is a common, highly lethal, complication of critical illness which has a high mortality1-4 and which is most 
frequently caused ...

科研

医学

A Rat Model of Ventricular Fibrillation and Resuscitation by Conventional Closed-chest Technique

A rat model of electrically-induced ventricular fibrillation followed by cardiac resuscitation using a closed chest technique that incorporates the basic components of cardiopulmonary resuscitation in humans is herein described. The model was developed in 1988 and has been used in approximately 70 peer-reviewed publications examining a myriad of resuscitation aspects including its physiology and pathophysiology, determinants of resuscitability, pharmacologic interventions, and even the effects of cell therapies. The model featured in this presentation includes: (1) vascular catheterization to measure aortic and right atrial pressures, to measure cardiac output by thermodilution, and to electrically induce ventricular fibrillation; and (2) tracheal intubation for positive pressure ventilation with oxygen enriched gas and assessment of the end-tidal CO2. A typical sequence of intervention entails: (1) electrical induction of ventricular fibrillation, (2) chest compression using a mechanical piston device concomitantly with positive pressure ventilation delivering oxygen-enriched gas, (3) electrical shocks to terminate ventricular fibrillation and reestablish cardiac activity, (4) assessment of post-resuscitation hemodynamic and metabolic function, and (5) assessment of survival and recovery of organ function. A robust inventory of measurements is available that includes &#8211; but is not limited to &#8211; hemodynamic, metabolic, and tissue measurements. The model has been highly effective in developing new resuscitation concepts and examining novel therapeutic interventions before their testing in larger and translationally more relevant animal models of cardiac arrest and resuscitation.

This article describes a rat model of electrically-induced ventricular fibrillation and resuscitation by chest compression, ventilation, and delivery of electrical shocks that simulates an episode of sudden cardiac arrest and conventional cardiopulmonary resuscitation. The model enables gathering insights on the pathophysiology of cardiac arrest and exploration of new resuscitation strategies.

室颤由传统的封闭胸技术大鼠模型和复苏

A rat model of electrically-induced ventricular fibrillation followed by cardiac resuscitation using a closed chest technique that incorporates the basic ...

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.

新生儿缺氧缺血性脑病的小猪模型

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

Breast Milk Enhances Growth of Enteroids: An Ex Vivo Model of Cell Proliferation

Human small intestinal enteroids are derived from the crypts and when grown in a stem cell niche contain all of the epithelial cell types. The ability to establish human enteroid ex vivo culture systems are important to model intestinal pathophysiology and to study the particular cellular responses involved. In recent years, enteroids from mice and humans are being cultured, passaged, and banked away for future use in several laboratories across the world. This enteroid platform can be used to test the effects of various treatments and drugs and what effects are exerted on different cell types in the intestine. Here, a protocol for establishing primary stem cell-derived small intestinal enteroids derived from neonatal mice and premature human intestine is provided. Moreover, this enteroid culture system was utilized to test the effects of species-specific breast milk. Mouse breast milk can be obtained efficiently using a modified human breast pump and expressed mouse milk can then be used for further research experiments. We now demonstrate the effects of expressed mouse, human, and donor breast milk on the growth and proliferation of enteroids derived from neonatal mice or premature human small intestine.

Breast Milk Enhances Growth of Enteroids: An Ex Vivo Model of Cell Proliferation

This protocol describes how to establish an enteroid culture system from neonatal mouse or premature human intestine as well as an efficient method to collect milk from mice.

母乳促进 Enteroids 的生长: 一个前体细胞增殖模型

Human small intestinal enteroids are derived from the crypts and when grown in a stem cell niche contain all of the epithelial cell types. The ability to ...

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.

用线 Myography 测定小鼠肠系膜动脉的等轴收缩力

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

The Lower Body Positive Pressure Treadmill for Knee Osteoarthritis Rehabilitation

Here, based on a clinician&rsquo;s point-of-view, we propose a two-model lower body positive pressure (LBPP) protocol (walking and squatting models) in addition to a clinical, functional assessment methodology, including details for further encouragement of the development of non-drug surgical intervention strategies in knee osteoarthritis patients. However, we only present the effect of LBPP training in improvement of pain and knee function in one patient through three-dimensional gait analysis. The exact, long-term effects of this approach should be explored in future studies.

Here, based on a clinician&#8217;s point-of-view, we propose a two-model lower body positive pressure (LBPP) protocol (walking and squatting models) in addition to a clinical, functional assessment methodology, including details for further encouragement of the development of non-drug surgical intervention strategies in knee osteoarthritis patients. However, we only present the effect of LBPP training in improvement of pain and knee function in one patient through three-dimensional gait analysis. The exact, long-term effects of this approach should be explored in future studies.

下体正压跑步机用于膝关节骨关节炎康复

Here, based on a clinician&rsquo;s point-of-view, we propose a two-model lower body positive pressure (LBPP) protocol (walking and squatting models) in ...

Noninvasive Electrocardiography in the Perinatal Mouse

Electrocardiography (ECG) has long been relied upon as an effective and reliable method of assessing cardiovascular (and cardiopulmonary) function in both human and animal models of disease. Individual heart rate, rhythm, and regularity, combined with quantitative parameters collected from ECG, serve to assess the integrity of the cardiac conduction system as well as the integrated physiology of the cardiac cycle. This article provides a comprehensive description of the methods and techniques used to perform a noninvasive ECG on perinatal and neonatal mouse pups as early as the first postnatal day, without requiring the use of anesthetics. This protocol was designed to directly address a need for a standardized and repeatable method for obtaining ECG in newborn mice. From a translational perspective, this protocol proves to be entirely effective for characterization of congenital cardiopulmonary defects generated using transgenic mouse lines, and particularly for analysis of defects causing lethality at or during the first postnatal days. This protocol also aims to directly address a gap in the scientific literature to characterize and provide normative data associated with maturation of the early postnatal cardiac conduction system. This method is not limited to a specific postnatal timepoint, but rather allows for ECG data collection in neonatal mouse pups from birth to postnatal day 10 (P10), a window that is of critical importance for modeling human diseases in vivo, with particular emphasis on congenital heart disease (CHD).

Here, we present a noninvasive electrocardiography (ECG) protocol, optimized for early postnatal mice, that does not require the use of anesthetics.

围产期小鼠中的非侵入性心电图

Electrocardiography (ECG) has long been relied upon as an effective and reliable method of assessing cardiovascular (and cardiopulmonary) function in both ...

A Murine Model of Fetal Exposure to Maternal Inflammation to Study the Effects of Acute Chorioamnionitis on Newborn Intestinal Development

Chorioamnionitis is a common precipitant of preterm birth and is associated with many of the morbidities of prematurity, including necrotizing enterocolitis (NEC). However, a mechanistic link between these two conditions remains yet to be discovered. We have adopted a murine model of chorioamnionitis involving lipopolysaccharide (LPS)-induced fetal exposure to maternal inflammation (FEMI). This model of FEMI induces a sterile maternal, placental, and fetal inflammatory cascade, which is also present in many cases of clinical chorioamnionitis. Although models exist that utilize live bacteria and more accurately mimic the pathophysiology of an ascending infection resulting in chorioamnionitis, these methods may cause indirect effects on development of the immature intestinal tract and the associated developing microbiome. Using this protocol, we have demonstrated that LPS-induced FEMI results in a dose-dependent increase in pregnancy loss and preterm birth, as well as disruption of normal intestinal development in offspring. Further, we have demonstrated that FEMI significantly increases intestinal injury and serum cytokines in offspring, while simultaneously decreasing goblet and Paneth cells, both of which provide a first line of innate immunity against intestinal inflammation. Although a similar model of LPS-induced FEMI has been used to model the association between chorioamnionitis and subsequent abnormalities of the central nervous system, to our knowledge, this protocol is the first to attempt to elucidate a mechanistic link between chorioamnionitis and later perturbations in intestinal development as a potential link between chorioamnionitis and NEC.

We developed a model of chorioamnionitis to simulate fetal exposure to maternal inflammation (FEMI) without complications of live organisms to examine the effects of FEMI on development of the offspring&#8217;s intestinal tract. This allows for study of mechanistic causes for development of intestinal injury following chorioamnionitis.

胎儿接触产妇炎症的穆林模型，研究急性胆管炎对新生儿肠道发育的影响

Chorioamnionitis is a common precipitant of preterm birth and is associated with many of the morbidities of prematurity, including necrotizing ...

Sterile Pericarditis in Aachener Minipigs As a Model for Atrial Myopathy and Atrial Fibrillation

Atrial fibrillation (AF) is the most common arrhythmia caused by structural remodeling of the atria, also called atrial myopathy. Current therapies only target the electrical abnormalities and not the underlying atrial myopathy. For the development of novel therapies, a reproducible large animal model of atrial myopathy is necessary. This paper presents a model of sterile pericarditis-induced atrial myopathy in Aachener minipigs. Sterile pericarditis was induced by spraying sterile talcum and leaving a layer of sterile gauze over the atrial epicardial surface. This led to inflammation and fibrosis, two crucial components of the pathophysiology of atrial myopathy, making the atria susceptible to the induction of AF. Two pacemaker electrodes were positioned epicardially on each atrium and connected to two pacemakers from different manufacturers. This strategy allowed for repeated non-invasive atrial programmed stimulation to determine the inducibility of AF at specified time points after surgery. Different protocols to test AF inducibility were used. The advantages of this model are its clinical relevance, with AF inducibility and the rapid induction of inflammation and fibrosis-both present in atrial myopathy-and its reproducibility. The model will be useful in the development of novel therapies targeting atrial myopathy and AF.

We describe a sterile pericarditis model in minipigs to study atrial myopathy and atrial fibrillation (AF). We present surgical and anesthetic techniques, strategies for vascular access, and a protocol to study the inducibility of AF.

Aachener Minipigs的无菌性心包炎作为心房肌病和心房颤动的模型

Atrial fibrillation (AF) is the most common arrhythmia caused by structural remodeling of the atria, also called atrial myopathy. Current therapies only ...

Effect of Hyaluronic Acid 35 kDa on an In Vitro Model of Preterm Small Intestinal Injury and Healing Using Enteroid-Derived Monolayers

In vitro scratch wound assays are commonly used to investigate the mechanisms and characteristics of epithelial healing in a variety of tissue types. Here, we describe a protocol to generate a two-dimensional (2D) monolayer from three-dimensional (3D) non-human primate enteroids derived from intestinal crypts of the terminal ileum. These enteroid-derived monolayers were then utilized in an in vitro scratch wound assay to test the ability of hyaluronan 35 kDa (HA35), a human milk HA mimic, to promote cell migration and proliferation along the epithelial wound edge. After the monolayers were grown to confluency, they were manually scratched and treated with HA35 (50 &#181;g/mL, 100 &#181;g/mL, 200 &#181;g/mL) or control (PBS). Cell migration and proliferation into the gap were imaged using a transmitted-light microscope equipped for live-cell imaging. Wound closure was quantified as percent wound healing using the Wound Healing Size Plugin in ImageJ.&#160;The scratch area and rate of cell migration and the percentage of wound closure were measured over 24 h. HA35 in vitro accelerates wound healing in small intestinal enteroid monolayers, likely through a combination of cell proliferation at the wound edge and migration to the wound area. These methods can potentially be used as a model to explore intestinal regeneration in the preterm human small intestine.

Effect of Hyaluronic Acid 35 kDa on an In Vitro Model of Preterm Small Intestinal Injury and Healing Using Enteroid-Derived Monolayers

This protocol describes a method to establish and perform a scratch wound assay on two-dimensional (2D) monolayers derived from three-dimensional (3D) enteroids isolated from non-human primate ileum.

透明质酸35 kDa对肠源单层早产小肠损伤体 外 模型及愈合的影响

In vitro scratch wound assays are commonly used to investigate the mechanisms and characteristics of epithelial healing in a variety of tissue types. ...