이 연구는 보스턴 사이 언티픽의 Neuromodulation에 의해 투자되었다.

1. 소개 : 척수의 자극, 또는 SCS는 임상 박사 노먼 쉴리 먼저 만성, 다루기 힘든 고통 (쉴리 외., 1967) 환자에 대한 구호를 제공하기 위해 시도 등의 컬럼을 통해 자극 전극을 이식하면, 1967 년 이후 적용되었습니다. SCS는 &quot;가까운 문&quot;두뇌 높은 센터 (로 통증 신호의 전송에을 억제하거나, 수, 터치 및 압력 감각을 중재 대형 myelinated 수입 성의 신경의 활성화를 posits 게이트 이론의 임상 구현한 것입니다 Melzack &amp; 월 1965). SCS에 대한 기술은 수십 년 동안 개선이 더 지느러미 열 자극하기위한보다 안정적인 자극 장비와 진화하고 있습니다. 이러한 개선의 핵심은 임상 전기 자극과 관련된 척수의 neuroanatomy과 neurophysiology의 증가 이해되었습니다. 이 이해는 SCS의 전산 모델링에서 고급되었습니다. 뉴런의 전산 모델링은 호지킨과 헉슬리의 수학적 모델이 첫 번째 (호지킨 및 헉슬리 1952 년) 설명 이후 신경 자극을위한 기본 메커니즘을 이해하는 데 사용되었습니다. 신경 세포 활동은 현재 분사와 세포외 잠재적인 분야로 적용 전기 분야에 의해 변조된 수 있습니다. Ranck는 질적 축삭의 주변에있는 세포 전압 변화 (Ranck, 1975)을 축삭 막의 일부 영역 depolarize하고 다른 hyperpolarize시킬 방법을 논의했다. SCS에 대한 전산 모델은 초기 코번과 신 (코번, 1980)에 의해 개발되었으며 크게 Struijk 및 SCS의 3 차원 필드 모델 (Holsheimer 및 Struijk, 1988)의 Holsheimer 개발로 시작, Holsheimer 및 동료에 의해 furthered했다. 그들의 계산 모델, 등 부분의 열 섬유 (Struijk 외., 1992)의 임계값에 대한 해부 매개 변수의 효과를 예상 지느러미 루트 섬유 (Struijk 외., 1993b)에 여진의 가능성 위치를 예측하고, CSF의 효과를 분석 임상 검증 (.; Holsheimer 외, 1995a;.. Holsheimer 외, 1994 그는 외, 1994)와 두께 (Struijk 외, 1993a).. 루트 섬유 (Holsheimer 외 이상 등의 열 섬유의 특혜 자극을 선호하는,, 모델은 연락 크기와 간격 (Holsheimer 및 Wesselink, 1997 Holsheimer 및 Struijk, 1992)에 대한 최적의 파라미터를 제안, 자극 리드 디자인의 설계에 크게 공헌했습니다. 1995b). 2. 방법 : 수학 모델 정의 유한 요소 수학 (FEM) 모델은 낮은 흉부 척수와 그 주변 환경의 생성되었습니다. FEM 모델은 척수 흰색과 회색 물질, 뇌척수, 두라, 경막외 공간 조직, 척추 뼈, 두 개의 원통형 multicontact 리드로 구성되어. 각각의 리드는 폴리머 (비 지휘 도메인, 1mm 길이) 절연의 1mm 길이로 구분하여 여덟 원통형 백금 - 이리듐 연락처 (지휘 도메인, 3mm 길이와 1.25 mm 직경)로 구성되어. 리드는 두라 위에, dorsally 위치하고, 대칭, 1mm 척수의 정중선의 양쪽에 있었다. 모델에서 연락처와 척수의 지느러미 표면 (dCSF) 사이의 뇌척수 계층의 &quot;두께&quot;는 3.2mm로 지정되었습니다. 모델의 형상은 그림 1A에 그림이며 전기 resistivities가 테이블에 주어진 I, 문학 (Holsheimer, 2002.; Wesselink 외, 1999)에서 주로 오는 값. 볼륨은 가까운 그림 1B에 그림과 같이 전극이 위치한 곳으로 지역에서 고밀도 메쉬와 백만 이상의 노드와 meshed했다. <img src="/files/ftp_upload/2443/2443fig1.jpg" alt="그림 1" /> 그림 1. 척수 및 multicontact 리드에 대한 FEM의 메쉬의 묘사. (A) 구성 요소 및 모델의 구조. (B) 모델 메쉬 - 전용 고밀도 부분은 표시됩니다. 메쉬는 변수 노드 밀도의 섹션으로 분할되었다 : 연락처 (≤ 300 μm의) 근처, 절연체, 두라 및 척수 (≤ 750 μm의), 경막외 공간 (≤ 3,000 μm의) 및 척추 뼈 (≤ 5,000 μm의). <img src="/files/ftp_upload/2443/2443table1.jpg" alt="표 1" /> 표 1 저항의 FEM 도메인의 가치 (Holsheimer, 2002;. Wesselink 외, 1999). 그리고 수정 (경막외 공간) 임상 데이터를 일치시킵니다. 척수의 기하학 (그림 2) 관련 문헌 소스의 기능의 조합을 사용하여 만들었습니다. . Struijk;. 탯줄의 단면은 (카메 야마 외, 1996 가메 야마 외에서 파생되었고, Struijk 외의 지느러미 루트 (DR) 궤도가 채택되었습니다.외., 1993b). 도설 열 (DC) 섬유의 일반적인 격자 (매니 퓰 레이터 방향과 100um dorsoventral 방향 200um, 그림 2A 참조)에 게재되었으며 rostrocaudal 방향으로 예상. 각 DR은 작은 직경 (그림 2B)의 bifurcated &#39;딸&#39;섬유에 연결된 큰 직경이 &#39;어머니&#39;섬유로 모델링되었다. <img src="/files/ftp_upload/2443/2443fig2.jpg" alt="그림 2" /> 그림 2. 척수 모델의 구조. 척수와 지느러미 열 섬유의 위치 (A) 트랜잭션 볼 수 있습니다. (B) 도설 뿌리는 어머니의 섬유 및 bifurcated 딸 섬유로 구성되어 있습니다. 어머니 섬유의 궤도는 Struijk 1993 년부터 디지털되었다. 척수 및 DR 섬유의 (C) 입체 볼 수 있습니다. 모델 조사 리드가 모델 내에 위치했다되면, stimulators의 두 가지 유형은 두 개의 병렬 연락처 전류를 정의하여 구현되었다. 단일 소스 시스템, 현재 제공하는 세 가지 방법이있다 : A. B.; 왼쪽 연락처는 모든 현재가 C., 두 연락처 각각은 현재의 50 %를 제공 가장 오른쪽 연락처는 모든 전류를 제공합니다. 우리는이 임상 응용 프로그램에 사실 가능성에도 불구하고 두 접점의 임피던스가, 평등한 가정입니다 여기에 있습니다. multisource 시스템은 각 연락처가 연락처 간의 1퍼센트 증분 현재 변경 제어 자체 전류 소스를 가지고 정의했다. 즉, 두 개의 연락처로 전달 총 전류는 multisource 시스템, 10mA 경우 각 연락처 현재는 너무 오래 각 연락처 동등한 10mA를 통해 전류의 합계로, 전체의 일부분으로 지정되었습니다. 예를 들어, 왼쪽 담당자는 가장 오른쪽 접촉 후 3.2 mA를 제공 것이 6.8 mA를 제공 할 수도 있습니다. 현재이 방법으로 프로그램 된의 multisource 시스템, 100 부분은 분할합니다. 각 시스템에 의해 등의 컬럼 내에서 활성의 영역을 계산하려면, 활성화 기능 분석이 수행되었다. 활성화 함수는 세포외 자극 전류가 주어진 전극과 섬유 도형에 대한 신경 조직에 적용되는 transmembrane 잠재력의 변화의 근사치입니다. 활성화 영역은 활성화 함수 (또는 축삭을 따라 전압의 차이가 단순히 초) 미리 정해진 임계값 (예 : 0.1mV/mm2)를 초과 모델에서 섬유의 로커스로 정의했다. 자극의 중앙 지점이 활성화의 3 차원 영역의 기하학적 중심으로 정의하고 계산되었다. 자극의 진폭을 확인하려면, 두 개의 연락처는 monopolar 구성에서 cathodes (50 % 두 연락처 50 % 부정적인 가능성) (모델 테두리에서 동일한 전류 밀도와 함께 제공되는 전류 공급)으로 지정되었다. 활성화된 최초의 섬유가 (이것은 항상 등의 칼럼 섬유되었습니다) 관찰되기 전까지는 자극의 진폭은 다음 반복 증가했다. 이 첫 번째 인증은 임상 환경에서 환자의 paresthesia 첫 인식 상관 관계를 규정하는 가정했다. 모델에서 전류는 다음 1.4 * (mA 먼저 섬유를 활성화하기 위해)로 증가했고 활성화의 결과로 지역의 중심이 계산되었다. 모든 스티어링 단계 (100:0로 0:100)의 Centroids는 이전 단계에서 결정 진폭과 함께 계산되었습니다. 중심 변화의 평균 해상도가 현재 단계로 나눈 중심 위치 범위되었다. 3. 결과 : 듀얼 리드 사이 mediolaterally 자극 핸들이 때, 계산 모델은 각 연락처에 대해 독립적인 전류 소스 장치가 하나의 소스 시스템 (100 대 3)보다 등의 열을 자극보다 중앙 지점을 대상 수 있다고 예측했다. 이 결과, 자극의 중심 지점의 조정의 해상도가 multisource 시스템 30 음, 단일 소스 시스템 (그림 3 참조)에 비해 약 50 배 증가합니다. <img src="/files/ftp_upload/2443/2443fig3.jpg" alt="그림 3" /> 그림 3. 컴퓨팅 모델은 다음과 같은 예측을합니다. A. 듀얼 리드 구성 : monopole의 자극과 연결 사이에 2.0 mm 분리. (2mm 리드 분리와 평균 1mm의 스텝 크기) mediolaterally 자극을 이동하면 모든 연락처에 대해 하나의 공유 전원을 제공 B. 단일 소스 장치는 자극 세 중앙 지점을 타겟팅할 수 있습니다. C : 1 % 증가, 또는 10 중앙 지점에서 현재 fractionalizing 때 10 % 증가 (1 %에 0.02 mm의 단계 크기 fractionalizing 때 각 연락처 등의 열에 옆으로 100 중앙 포인트를 타겟팅할 수 전용 전원과 장치 단계 평균 10 %의 단계 0.2 mm).

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B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Paresthesia+Thresholds+in+Spinal+Cord+Stimulation:+A+Comparison+of+Theoretical+Results+with+Clinical+Data.">Paresthesia Thresholds in Spinal Cord Stimulation: A Comparison of Theoretical Results with Clinical Data.</a> IEEE Trans Rehab Eng. 1, 101-107 (1993).</li><li>Struijk, J. J., Holsheimer, J., Boom, 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=Excitation+of+dorsal+root+fibers+in+spinal+cord+stimulation:+a+theoretical+study.">Excitation of dorsal root fibers in spinal cord stimulation: a theoretical study.</a> IEEE Trans Biomed Eng. 40, 632-639 (1993).</li><li>Struijk, J. J., Holsheimer, J., van der Heide, G. G., Boom, 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=Recruitment+of+dorsal+column+fibers+in+spinal+cord+stimulation:+influence+of+collateral+branching.">Recruitment of dorsal column fibers in spinal cord stimulation: influence of collateral branching.</a> IEEE Trans Biomed Eng. 39, 903-912 (1992).</li><li>Struijk, J. J., Holsheimer, J., van Veen, B. K., Boom, 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=Epidural+spinal+cord+stimulation:+calculation+of+field+potentials+with+special+reference+to+dorsal+column+nerve+fibers.">Epidural spinal cord stimulation: calculation of field potentials with special reference to dorsal column nerve fibers.</a> IEEE Trans Biomed Eng. 38, 104-110 (1991).</li><li>Wesselink, W. A., Holsheimer, J., King, G. W., Torgerson, N. A., Boom, H. B. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitative+Aspects+of+the+Clinical+Performance+of+Transverse+Tripolar+Spinal+Cord+Stimulation.">Quantitative Aspects of the Clinical Performance of Transverse Tripolar Spinal Cord Stimulation.</a> Neuromodulation. 2, 5-14 (1999).</li></ol>

저자는 보스턴 사이 언티픽의 Neuromodulation 직원입니다.

고해상도로 등의 열에 센터 자극 영역 능력은 환자 paresthesia - 통증의 중복의 더 나은 최적화를 위해 허용할 수 있습니다. 그것이 주어진 환자에이고, 등 부분의 열에 활성화의 지역은 고통 영역의 범위를 최대화하기 위해 초점을 맞추고있을 수 있습니다 반면 최소화 부작용 (모터 또는 자율을 undesireable 장소에 paresthesia를 생성하거나 만들 수 있습니다 바람직하지 않은 섬유의 자극에 의​​한 효과).

<ul><li> 신경 세포 ( <a href="http://www.neuron.yale.edu">http://www.neuron.yale.edu</a> ) </li><li> ANSYS (캐논 즈 버그, PA, <a href="http://www.ansys.com">http://www.ansys.com</a> ) </li><li> Matlab (내틱, MA, <a href="http://www.mathworks.com">http://www.mathworks.com</a> ) </li></ul>

dorsal column steerability with dual parallel leads using dedicated power sources:  a computational model

에서 척수의 자극 (SCS), 고통스러운 신체 영역을 통해 자극 유발 paresthesia의 일치는 치료 효능에 대해 절대 필요 조건이다. 환자 통증 패턴이 고유 수 있기 때문에 일반적인 자극 구성 등의 경막외 공간에 나란히 두 개의 리드의 위치입니다. 이 구조는 mediolaterally 더 고통 - paresthesia의 중복을 달성하기 등의 컬럼을 통해 자극 현재 핸들의 유연성을 제공합니다. 정확한 섬유 직경 분포와 수학적 모델을 사용하여, 우리는 이중 병렬의 능력을 연구하는 것은 이중 병렬에 인접한 연락처 사이의 자극을 조종할 연결하면 함께 (1) 단일 소스 시스템을 사용하여 리드하고, (2) 다중 소스 시스템 각 연락처에 대해 현재의 소스를 바쳤다. epidurally 위치를 이중 병렬로 낮은 흉부 척수의 볼륨 도체 모델 (2mm 분리) percutaneous 리드가 처음 만들어진, 그리고 전기장은 ANSYS, 유한 요소 모델링 도구를 사용하여 계산되었다. 10 음 섬유에 대한 활성화 함수는 등의 열에있는 신경 섬유 Ranvier의 노드 따라 세포 잠재력의 두 번째 차이로 계산되었다. 활성화 (VOA)와 소리의 중앙 지점의 볼륨은 활성화 함수의 미리 결정된 임계값을 사용하여 계산되었다. 모델은 듀얼 8 연락처 자극 리드에 전용 전원 시스템 대비 단일 소스와 함께 현장 조정 결과를 비교했다. 모델은 다중 소스 시스템이 단일 소스 시스템 (100 대 3) 및 매니 퓰 레이터 핸들에 대한 의미 조향 단계보다 등의 열을 자극보다 중앙 지점을 대상 수 있다고 예측하는 것은 멀티 소스 시스템 VS 1mm에 대한 0.02 mm입니다 단일 소스 시스템, 50 배 향상. 고해상도로 등의 열에 센터 자극 영역 능력은 환자 paresthesia - 통증의 중복의 더 나은 최적화를 위해 허용할 수 있습니다.

Watch this Scientific Journal Video about Dorsal Column Steerability with Dual Parallel Leads using Dedicated Power Sources:  A Computational Model at JoVE.com

Dorsal Column Steerability with Dual Parallel Leads using Dedicated Power Sources:  A Computational Model

척수의 자극의 수학적 모델을 사용하여, 우리는 (각 연락처에 대해 독립 전원을 가진 멀티 소스 시스템 등의 열을 자극보다 중앙 지점 (100 VS 3) 대상 수있는 발견 및 50 배 더 많은 필드 스티어링 해상도를 가지고 단일 소스 시스템보다 0.02mm VS 1mm).

전용 전원을 사용하여 이중 병렬 리드와 도설 칼럼 Steerability : 전산 모델

In spinal cord stimulation (SCS), concordance of stimulation-induced paresthesia over painful body regions is a necessary condition for therapeutic ...

dorsal-column-steerability-with-dual-parallel-leads-using-dedicated

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11.7K 조회수.  Neuromodulation. 척수의 자극의 수학적 모델을 사용하여, 우리는 (각 연락처에 대해 독립 전원을 가진 멀티 소스 시스템 등의 열을 자극보다 중앙 지점 (100 VS 3) 대상 수있는 발견 및 50 배 더 많은 필드 스티어링 해상도를 가지고 단일 소스 시스템보다 0.02mm VS 1mm).

비디오: Dorsal Column Steerability with Dual Parallel Leads using Dedicated Power Sources:  A Computational Model

A Novel Capsulorhexis Technique Using Shearing Forces with Cystotome

Purpose:
To demonstrate a capsulorhexis technique using predominantly shearing forces with a cystotome on a virtual reality simulator and on a human eye.
Method:
Our technique involves creating the initial anterior capsular tear with a cystotome to raise a flap. The flap left unfolded on the lens surface. The cystotome tip is tilted horizontally and is engaged on the flap near the leading edge of the tear. The cystotome is moved in a circular fashion to direct the vector forces. The loose flap is constantly swept towards the centre so that it does not obscure the view on the tearing edge.
Results:
Our technique has the advantage of reducing corneal wound distortion and subsequent anterior chamber collapse. The capsulorhexis flap is moved away from the tear leading edge allowing better visualisation of the direction of tear. This technique offers superior control of the capsulorhexis by allowing the surgeon to change the direction of the tear to achieve the desired capsulorhexis size.
Conclusions:
The EYESI Surgical Simulator is a realistic training platform for surgeons to practice complex capsulorhexis techniques. The shearing forces technique is a suitable alternative and in some cases a far better technique in achieving the desired capsulorhexis.

This video demonstrates a novel capsulorhexis technique in modern cataract surgery. Capsulorhexis is the most difficult and important part of phacoemulsification surgery.

Cystotome와 쉬어링 부대를 사용하여 소설 Capsulorhexis 기법

Purpose:
To demonstrate a capsulorhexis technique using predominantly shearing forces with a cystotome on a virtual reality simulator and on a human eye....

연구

의학

In vivo Dual Substrate Bioluminescent Imaging

Our understanding of how and when breast cancer cells transit from established primary tumors to metastatic sites has increased at an exceptional rate since the advent of in vivo bioluminescent imaging technologies 1-3. Indeed, the ability to locate and quantify tumor growth longitudinally in a single cohort of animals to completion of the study as opposed to sacrificing individual groups of animals at specific assay times has revolutionized how researchers investigate breast cancer metastasis. Unfortunately, current methodologies preclude the real-time assessment of critical changes that transpire in cell signaling systems as breast cancer cells (i) evolve within primary tumors, (ii) disseminate throughout the body, and (iii) reinitiate proliferative programs at sites of a metastatic lesion. However, recent advancements in bioluminescent imaging now make it possible to simultaneously quantify specific spatiotemporal changes in gene expression as a function of tumor development and metastatic progression via the use of dual substrate luminescence reactions. To do so, researchers take advantage for two light-producing luciferase enzymes isolated from the firefly (Photinus pyralis) and sea pansy (Renilla reniformis), both of which react to mutually exclusive substrates that previously facilitated their wide-spread use in in vitro cell-based reporter gene assays 4. Here we demonstrate the in vivo utility of these two enzymes such that one luminescence reaction specifically marks the size and location of a developing tumor, while the second luminescent reaction serves as a means to visualize the activation status of specific signaling systems during distinct stages of tumor and metastasis development. Thus, the objectives of this study are two-fold. First, we will describe the steps necessary to construct dual bioluminescent reporter cell lines, as well as those needed to facilitate their use in visualizing the spatiotemporal regulation of gene expression during specific steps of the metastatic cascade. Using the 4T1 model of breast cancer metastasis, we show that the in vivo activity of a synthetic Smad Binding Element (SBE) promoter was decreased dramatically in pulmonary metastasis as compared to that measured in the primary tumor 4-6. Recently, breast cancer metastasis was shown to be regulated by changes within the primary tumor microenvironment and reactive stroma, including those occurring in fibroblasts and infiltrating immune cells 7-9. Thus, our second objective will be to demonstrate the utility of dual bioluminescent techniques in monitoring the growth and localization of two unique cell populations harbored within a single animal during breast cancer growth and metastasis.

In vivo Dual Substrate Bioluminescent Imaging

Herein we describe the methods to construct, visualize, and quantify the bioluminescent reactions of both firefly and renilla luciferase enzymes expressed in metastatic breast cancer cells during their growth and metastasis in vivo.

생체 듀얼 기판 발광 생물 이미징에

Our understanding of how and when breast cancer cells transit from established primary tumors to metastatic sites has increased at an exceptional rate ...

Deep Neuromuscular Blockade Leads to a Larger Intraabdominal Volume During Laparoscopy

Shoulder pain is a commonly reported symptom following laparoscopic procedures such as myomectomy or hysterectomy, and recent studies have shown that lowering the insufflation pressure during surgery may reduce the risk of post-operative pain. In this pilot study, a method is presented for measuring the intra-abdominal space available to the surgeon during laproscopy, in order to examine whether the relaxation produced by deep neuromuscular blockade can increase the working surgical space sufficiently to permit a reduction in the CO2 insufflation pressure. Using the laproscopic grasper, the distance from the promontory to the skin is measured at two different insufflation pressures: 8 mm Hg and 12 mm Hg. After the initial measurements, a neuromuscular blocking agent (rocuronium) is administered to the patient and the intra-abdominal volume is measured again. Pilot data collected from 15 patients shows that the intra-abdominal space at 8 mm Hg with blockade is comparable to the intra-abdominal space measured at 12 mm Hg without blockade. The impact of neuromuscular blockade was not correlated with patient height, weight, BMI, and age. Thus, using neuromuscular blockade to maintain a steady volume while reducing insufflation pressure may produce improved patient outcomes.

This article presents a method for measuring the working abdominal volume during laproscopic myomectomy using the surgical grasper, and applies this technique to obtain pilot data on whether deep neuromuscular blockade (NMB) can enable the use of lower insufflation pressure. Reduced insufflation pressure during laproscopic surgery has been shown to reduce post-operative pain, and thus the use of NMB during surgery may enable improved patient outcomes.

깊은 신경 근육 학 봉쇄 복강경​​시 복강 큰 볼륨으로 오퍼

Shoulder pain is a commonly reported symptom following laparoscopic procedures such as myomectomy or hysterectomy, and recent studies have shown that ...

Ischemic Tissue Injury in the Dorsal Skinfold Chamber of the Mouse: A Skin Flap Model to Investigate Acute Persistent Ischemia

Despite profound expertise and advanced surgical techniques, ischemia-induced complications ranging from wound breakdown to extensive tissue necrosis are still occurring, particularly in reconstructive flap surgery. Multiple experimental flap models have been developed to analyze underlying causes and mechanisms and to investigate treatment strategies to prevent ischemic complications. The limiting factor of most models is the lacking possibility to directly and repetitively visualize microvascular architecture and hemodynamics. The goal of the protocol was to present a well-established mouse model affiliating these before mentioned lacking elements. Harder et al. have developed a model of a musculocutaneous flap with a random perfusion pattern that undergoes acute persistent ischemia and results in ~50% necrosis after 10 days if kept untreated. With the aid of intravital epi-fluorescence microscopy, this chamber model allows repetitive visualization of morphology and hemodynamics in different regions of interest over time. Associated processes such as apoptosis, inflammation, microvascular leakage and angiogenesis can be investigated and correlated to immunohistochemical and molecular protein assays. To date, the model has proven feasibility and reproducibility in several published experimental studies investigating the effect of pre-, peri- and postconditioning of ischemically challenged tissue.

The window of the murine dorsal skinfold chamber presented visualizes a zone of acute persistent ischemia of a musculocutaneous flap. Intravital epi-fluorescence microscopy permits for direct and repetitive assessment of the microvasculature and quantification of hemodynamics. Morphologic and hemodynamic results can further be correlated with histological and molecular analyses.

마우스의 등쪽 피하 지방 상공 회의소에서 허혈성 조직 손상 : 피부 플랩 모델은 급성 영구 허혈을 조사하기

Despite profound expertise and advanced surgical techniques, ischemia-induced complications ranging from wound breakdown to extensive tissue necrosis are ...

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.

Myography 와이어를 사용 하 여 마우스 Mesenteric 동맥의 isometric 수축 측정

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

Murine Model of Central Venous Stenosis using Aortocaval Fistula with an Outflow Stenosis

Central venous stenosis is an important entity contributing to arteriovenous fistula (AVF) failure. A murine AVF model was modified to create a partial ligation of the inferior vena cava (IVC) in the outflow of the fistula, mimicking central venous stenosis. Technical aspects of this model are introduced. The aorta and IVC are exposed, following an abdominal incision. The infra-renal aorta and IVC are dissected for proximal clamping, and the distal aorta is exposed for puncture. The IVC at the midpoint between the left renal vein and the aortic bifurcation is carefully dissected to place an 8-0 suture beneath the IVC. After clamping the aorta and IVC, an AVF is created by puncturing the infra-renal aorta through both walls into the IVC with a 25 G needle, followed by ligating a 22 G intra-venous (IV) catheter and IVC together. The catheter is then removed, creating a reproducible venous stenosis without occlusion. The aorta and IVC are unclamped after confirming primary hemostasis. This novel model of central vein stenosis is easy to perform, reproducible, and will facilitate studies on AVF failure.

An aortocaval fistula was created by puncturing the murine infra-renal aorta through both walls into the inferior vena cava and was followed by creation of a stenosis in its outflow via partial ligation of the inferior vena cava. This reproducible model can be used to study central venous stenosis.

유출 협착증을 가진 Aortocaval 누공을 사용하여 중앙 정맥 협착증의 뮤린 모형

Central venous stenosis is an important entity contributing to arteriovenous fistula (AVF) failure. A murine AVF model was modified to create a partial ...

A Porcine Corneal Endothelial Organ Culture Model Using Split Corneal Buttons

Experimental research on corneal endothelial cells is associated with several difficulties. Human donor corneas are scarce and rarely available for experimental investigations as they are normally needed for transplantation. Endothelial cell cultures often do not translate well to in vivo situations. Due to the biostructural characteristics of non-human corneas, stromal swelling during cultivation induces substantial corneal endothelial cell loss, which makes it difficult to perform cultivation for an extended period of time. Deswelling agents such as dextran are used to counteract this response. However, they also cause significant endothelial cell loss. Therefore, an ex vivo organ culture model not requiring deswelling agents was established. Pig eyes from a local slaughterhouse were used to prepare split corneal buttons. After partial corneal trephination, the outer layers of the cornea (epithelium, bowman layer, parts of the stroma) were removed. This significantly reduces corneal endothelial cell loss induced by massive stromal swelling and Descemet&#39;s membrane folding throughout longer cultivation periods and improves general preservation of the endothelial cell layer. Subsequent complete corneal trephination was followed by the removal of the split corneal button from the remaining eye bulb and cultivation. Endothelial cell density was assessed at follow-up times of up to 15 days after preparation (i.e., days 1, 8, 15) using light microscopy. The preparation technique used allows a better preservation of the endothelial cell layer enabled by less stromal tissue swelling, which results in slow and linear decline rates in split corneal buttons comparable to human donor corneas. As this standardized organo-typically cultivated research model for the first time allows a stable cultivation for at least two weeks, it is a valuable alternative to human donor corneas for future investigations of various external factors with regards to their effects on the corneal endothelium.

Here, a step-by-step protocol for the preparation and cultivation of porcine split corneal buttons is presented. As this organo-typically cultivated organ culture model shows cell death rates within 15 days, comparable to human donor corneas, it represents the first model allowing long-term cultivation of non-human corneas without adding toxic dextran.

분할 각막 단추를 사용하여 돼지 각막 내피 내피 기관 문화 모형

Experimental research on corneal endothelial cells is associated with several difficulties. Human donor corneas are scarce and rarely available for ...

In Vivo Quantification of Hip Arthrokinematics during Dynamic Weight-bearing Activities using Dual Fluoroscopy

Several hip pathologies have been attributed to abnormal morphology with an underlying assumption of aberrant biomechanics. However, structure-function relationships at the joint level remain challenging to quantify due to difficulties in accurately measuring dynamic joint motion. The soft tissue artifact errors inherent in optical skin marker motion capture are exacerbated by the depth of the hip joint within the body and the large mass of soft tissue surrounding the joint. Thus, the complex relationship between bone shape and hip joint kinematics is more difficult to study accurately than in other joints. Herein, a protocol incorporating computed tomography (CT) arthrography, three-dimensional (3D) reconstruction of volumetric images, dual fluoroscopy, and optical motion capture to accurately measure the dynamic motion of the hip joint is presented. The technical and clinical studies that have applied dual fluoroscopy to study form-function relationships of the hip using this protocol are summarized, and the specific steps and future considerations for data acquisition, processing, and analysis are described.

In Vivo Quantification of Hip Arthrokinematics during Dynamic Weight-bearing Activities using Dual Fluoroscopy

Dual fluoroscopy accurately captures in vivo dynamic motion of human joints, which can be visualized relative to reconstructed anatomy (e.g., arthrokinematics). Herein, a detailed protocol to quantify hip arthrokinematics during weight-bearing activities of daily living is presented, including the integration of dual fluoroscopy with traditional skin marker motion capture.

인 비보 이중 불소시경을 이용한 동적 체중 베어링 활동 중 고관절 관절역학의 정량화

Several hip pathologies have been attributed to abnormal morphology with an underlying assumption of aberrant biomechanics. However, structure-function ...

Modified Posterior Vertebral Column Resection for Patients with Thoracolumbar Kyphotic Deformity

Old compression vertebrae fracture or congenital kyphoscoliosis with abnormal vertebral body development and other diseases that invade the spine may cause severe thoracolumbar kyphotic deformity, often accompanied by intractable low back pain or compression of the spinal cord, leading to severe neurological symptoms or even paralysis. If conservative treatment cannot relieve the symptoms or correct the deformities, surgical treatment is usually needed. For severe kyphotic deformity, reconstruction of the physiological curvature and rigid fixation determine the prognosis of the patients. Osteotomy and orthopedics are the standard procedure for deformities with severe compression of the front and middle column, but the trauma to the patients is high, with a long operation time and massive blood loss. To avoid these disadvantages, we have developed a modified technique to remove the diseased vertebra unilaterally. In this technique, we use a modified trephine to resect the vertebral columns like in the pedicle screw technique by adding a locking instrument that can restrict the trephine to lower the risk of osteotomy and shorten the surgery time and blood loss.

We describe a modified technique for resecting the posterior vertebral column unilaterally based on a modified trephine for patients with thoracolumbar kyphotic deformity.

흉요추 후만 기형 환자를 위한 수정된 후방 척추 기둥 절제술

Old compression vertebrae fracture or congenital kyphoscoliosis with abnormal vertebral body development and other diseases that invade the spine may ...

Rat DRG 압축 모델을 위한 표준화된 Tuina 프로토콜

Analgesic Effect of Tuina on Rat Models with Compression of the Dorsal Root Ganglion Pain

Neuropathic pain is a prevalent condition that affects 6.9%-10% of the population and results from nerve damage due to various etiologies, such as lumbar disc herniation, spinal canal stenosis, and intervertebral foramen stenosis. Although Tuina, a traditional Chinese manual therapy, has shown analgesic effects in clinical practice for the treatment of neuropathic pain, its underlying neurobiological mechanisms remain unclear. Animal models are essential for elucidating the basic principles of Tuina. In this study, we propose a standardized Tuina protocol for rats with compression of the dorsal root ganglion (DRG), which involves inducing DRG compression by inserting a stainless steel rod into the intervertebral foramen, performing Tuina manipulation with specific parameters of location, intensity, and frequency in a controlled environment, and assessing the behavioral and histopathological outcomes of Tuina treatment. This article also discusses the potential clinical implications and limitations of the study and suggests directions for future research on Tuina.

저자 스포트라이트: 등뿌리 신경절 통증을 압박하는 쥐 모델에 대한 Tuina의 진통 효과  

This article presents a manipulation for treating chronic compression of the dorsal root ganglion in rats using Tuina therapy, along with a method for evaluating its effectiveness based on pain behavior and histopathological results.

등쪽 뿌리 신경절 통증의 압축이 있는 쥐 모델에 대한 Tuina의 진통 효과

Neuropathic pain is a prevalent condition that affects 6.9%-10% of the population and results from nerve damage due to various etiologies, such as lumbar ...