DRはグラントの開始ドイツ研究協会（DFG）研究助成（RA 1分の1848）と欧州研究評議会からの支援を認めるものです。 VNが欧州研究評議会上級研究者賞からの財政支援を承認し、医学賞での連邦教育研究省のイノベーション。

π-FBG検出器の1。光音響特性評価<ol><li>寒天に懸濁し、顕微鏡球の調製： <ol><li>ガラスビーカー中で蒸留水を用いて寒天粉末（1.3重量％）を混合する。沸点に近い解を加熱し、溶液が透明と気泡の自由になるまで、寒天粉末を溶解するために、ホットプレートマグネチック·スターラー·デバイスを使用してください。あるいは、寒天溶液をガラス攪拌棒を使用して手動で実行撹拌有する従来のマイクロ波を用いて加熱してもよい。プラスチック金型に高温の溶液を注ぎ、その先端に例えば注射器を切り出し。 </li><li>寒天ソリューションに微細な球体の少量をふりかけ、溶液が完全に凝固するまで待ちます。プランジ​​ャーを押すことにより、金型から固体寒天ファントムを取る。 </li><li>実体顕微鏡下でファントムを表示するには、単一の微細な球体が含まれている寒天の小片をカット。 </li><li>ステップ1.1.1を繰り返し、Tを追加寒天ソリューションOつの微細な球体を含有する固体寒天作品。 </li><li>固化した後、微細な球体が、ファントムの表面に近い位置するように、顕微鏡下で寒天ファントムを切った。 </li></ol></li><li>光音響測定<ol><li> π-FBGの両側にしっかりと繊維を保持するために、2つのV溝ファイバホルダを使用し、三次元（XYZ）変換コンピュータ操作ステージにホルダーを接続されている。繊維は、超音波の伝播を可能にするために沈められていることを確認してください。 </li><li>ハイパワーナノ秒パルスレーザ光を光ファイバの異なる部分を照射することにより、検知π-FBG要素のおおよその位置を検索します。照明は、π-FBGに対して実行されたときしかし、弱い塗膜の光吸収は、信号が作成されます。 </li><li> π-FBGの真下に寒天包埋顕微球を配置します。微視的な球は、肉眼で見えるはずです。 </li><li>並進ステージを使用して、微細な球体からの信号が最も強く、その対応する時間遅延が最も短い位置を見つけるために地面に平行な面内でπ-FBGの2次元走査を行う。 </li><li>微視的な球に最大の電力を供給する照明への最後の調整を行う。 </li><li>移動ステージを使用すると、π-FBGの3Dスキャンを実行し、それぞれの位置のための信号を記録します。 </li><li>超音波検出器の空間依存の周波数応答を得るために、フーリエ記録された時間領域の超音波信号に変換を行う。 </li></ol></li></ol>堅牢性とπ-FBG検出器の性能の感度2。推定<ol><li> π-FBGの両側にしっかりと繊維を保持し、π-FBGを沈めるために2つのV溝ファイバホルダを使用しています。 </li><li> π-FBGに直面して頑丈に暗いプレートまたはグラファイト棒を配置し、それをウィットを照らす強い音場を作成するには、H、高出力ナノ秒パルスレーザ光。 </li><li>水タンク内の水ポンプを配置し、環境条件の急激な変化を作成するために、電源を入れます。 </li><li>システムのロバスト性を推定するために、ロック回路で出力を測定する両方のオン·オフ。まだロックが行われない場合には、正確に超音波信号を検出することができない。 </li><li>水ポンプの電源をオフにします。 </li><li>原因ソースの高コヒーレンスに対する感度で利益を推定するために、低コヒーレンス光源と広帯域パルスレーザーを交換し、音響測定を繰り返します。低コヒーレンス光源を用いた場合、感度の大きさのオーダーを超える減少が期待されている。 </li></ol>

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著者は、彼らが競合する経済的利益を持っていないことを宣言します。

結論として、超音波検出のための新たな光学的方法は、π-FBG及びパルス干渉法の組み合わせに基づいており、導入される。技術は、ほとんど任意の物体照明パターンを可能にする検出素子の透明性により光音響イメージング用途に特に適している。これとは対照的に、標準的な圧電基づいて超音波検出器は不透明であるため、かさばるイメージングセットアップにつながる、画像化されたオ?...

超音波検出器は、多くの撮像用途において重要な役割を果たす。従来、超音波を電圧信号1に圧力波を変換する圧電変換器によって検出される。光音響イメージングでは、超音波は高出力の変調光2-6でオブジェクトを照射することにより、熱膨張の過程を経て生成されます。圧電トランスデューサは、光音響の用途に最適な方法であるが、小型化された圧電トランスデューサは、多くの場合、低感度を特徴としているため、それらの使用は、多くの場合、主に小型化の妨げとなる。圧電変換器は光学的に不透明であるため、また、それらは深刻な使用可能な結像構成の可能性を制限する、撮像対象物への光の送達を妨害し得る。トランスデューサに物体から後方散乱された光は、超音波の適切な検出を制限し、光誘起によるparasitにイメージング·システムの設計を複雑にし得るトランスデューサ7でのICの信号。 超音波の光学検出器は、光音響イメージングシナリオ8月12日には多くの利点を提供した圧電振動子に可能な代替として認識されている：彼らは多くの場合、透明であり、通常、感度を失うことなく小型化することができる。光検出器の動作原理は、超音波の存在に光媒体で作成された微小な変形の干渉検出である。多くの場合、光共振器は、光信号の位相に対する変形の影響を増大させるため、拡張された持続時間の間、摂動媒体に光を捕捉することによって検出感度を向上させるために使用される。これらの場合、光学的検出スキームを直接共振器内で変形を構​​造化するために関連する共鳴波長の変化を監視することに基づいている。最も一般的には、狭線幅の連続波（CW）技術はCWレーザを目に同調されて使用される電子共鳴波長。共鳴波長の小さな変化、従って/伝達の強度のばらつきを引き起こす共振内でレーザの波長の相対的な位置を変更は容易にモニターすることができるレーザ光を、反射。共鳴シフトは、例えば圧力、温度や振動の大きな変動に起因して、強すぎる場合は、共振を効果的に検出器13を飽和させ、完全に離れて、レーザの波長からシフトさせてもよい。 パルス干渉14は、信号飽和の制限に対する解決策を提供しており、揮発性の環境条件の下で超音波検出を可能にします。 CW方式の線幅を狭くするとは対照的に、パルス干渉法は、共振器を照明するために、広帯域パルス光源を使用する。共振はシフトしながら、この場合に、共振器は、その共振周波数に対応する波長のみを透過、バンドパスフィルタとして機能する再直交14,15にロックされ、マッハツェンダ干渉計を用いることによって、共振器の出力における光信号の波長の変化を測定することによって検出した。自動リセット回路は、直ちにそれが、環境条件の極端な変化に失われた場合には、干渉計の動作点を復元するために使用される。なぜなら源の比較的広い帯域幅、共振波長が過酷な環境条件下で安定した検出動作が可能であっても強力な摂動の下で照明された帯域内に留まる。インタロゲーションのためのコヒーレント光源を使用すること、 すなわち、光パルスは、低ノイズ検出を容易にする。 我々の実験で使用し、対応するパルス干渉計システムを図1に示す。質問に用いるパルスレーザは、繰り返し60ミリワットの出力パワーを有する100MHzの速度および100上のスペクトル幅90フェムト秒のパルスを生成し程度。光学フィルターは、約0.4ナノメートルのFWHMスペクトル幅を持っていたし、共振の周波数に同調した。フィルタの後、光増幅器は、フィルタリングの有意な損失を補償するために使用した。追加のフィルタ、増幅器からの増幅された自然放出を減少させるために、増幅段の後に塗布した。私たちの実験で使用した共振器は、特に超音波センシング医療用Teraxion社製π位相シフトファイバブラッググレーティング（π-FBG）8、IS、π-のFBGは、全ファイバ部品であるという利点を持っているしたがって、堅牢で小さい。 図2は、本研究で使用した光ファイバの寸法および15MHzの小型化された血管内超音波（IVUS）は、圧電変換器との間の比較を示す。このような平面導波路で作製したマイクロリング共振器などのいくつかの代替共鳴ベースの検出手法は、コンポーネントの少なくとも結合繊維を必要とする入力と出力、より壊れやすいデバイスにつながるか、小型化を妨げるのどちらか。これとは対照的に、π-のFBGは、ファイバ内のコンポーネントであり、追加のファイバ結合を必要としません。 π-FBGの共振は、その中心部にあるπ位相シフトによって作成されます。光は、格子自体の長さよりもかなり短いファイバの一部にわたってπ位相シフトの周りに捕捉される。我々の実験において、π-FBGは4mmでκ= 2mmの結合係数の長さを有し-1およびその感度は、感度は指数関数的にκの速度で、格子の中心から減少に伴って、その長さに沿って不均一に分布した。感度分布（SD）の全幅半値（FWHM）は約350であった。格子の共鳴幅は、次式に従って、その長さとその結合係数の両方によって決定される。 <img alt="式（1）" fo:content-width="1.5in" src= &quot;/ files/ftp_upload/50847/50847eq1.jpg&quot;幅= &quot;150&quot; /&gt;（1） λは共振波長であり、n effはファイバ8の導波モードの実効屈折率である。 π-FBG検出器は、イメージング用途に適しているかどうかを評価するために、その空間的依存性応答は、広い周波数帯域にわたって測定する必要がある。従来の音響技術が使用されるときは、このタスクは非常に困難である。そこで、透明な寒天内に埋め込 ​​ま暗い微視的球体が光音響点光源として機能する超音波検出器の特性評価のために16光音響法を用いる。我々の実験では、微視的球体は、約100μmの直径を有し、10Hzの繰返し率、約8ナノ秒のパルス持続時間、及び200ミリワットの平均電力と高電力ナノ秒光パルスで照射される。微視的SPHに堆積した光エネルギーERES光音響効果により、広帯域超音波信号を生成する。 π-FBG検出器は、その空間に依存音響応答を得るために、比較的微細な球体に変換されます。 図3は、光音響実験の図を示している。一般に、この技術は、超音波検出器の種類を特徴付けるために使用することができる。

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			<td height="43" style="height:43px;width:216px;">&#960;-FBG</td>
			<td style="width:71px;">Teraxion Inc.</td>
			<td style="width:119px;"></td>
			<td style="width:167px;">&#160;Custom made device</td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:216px;">microscopic sphere</td>
			<td style="width:71px;">Cospheric LLC</td>
			<td style="width:119px;">BKPMS 90-106um- 10g</td>
			<td style="width:167px;">100 &#181;m polyethylene microsphere</td>
		</tr>
		<tr height="64">
			<td height="64" style="height:64px;width:216px;">Femto-second pulse laser used for interrogation&#160;</td>
			<td style="width:71px;">Menlo Systems GmbH</td>
			<td style="width:119px;">T-Light Femtosecond Laser</td>
			<td style="width:167px;"></td>
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		<tr height="64">
			<td height="64" style="height:64px;width:216px;">Optical filter</td>
			<td style="width:71px;">Optoplex Corporation</td>
			<td style="width:119px;">2-Port Optical Tunable Filter (50 GHz)</td>
			<td style="width:167px;"></td>
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			<td height="64" style="height:64px;width:216px;">Optical amplifier</td>
			<td style="width:71px;">Amonics</td>
			<td style="width:119px;">AEDFA-PM-PA-35-B-FC</td>
			<td style="width:167px;">Benchtop 35dB Gain Pre Amp Polarization Maintaining EDFA&#160;</td>
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			<td height="232" style="height:232px;width:216px;">50/50 coupler</td>
			<td style="width:71px;">OZ-Optics</td>
			<td style="width:119px;">FUSED-22-1550-8/125-50/50-3S3S3S3S-3-0.5-PM</td>
			<td style="width:167px;">Fused 2x2 fiber splitter with 0.5 meter long, 3mm OD PVC jacketed 1550nm 8/125&#956; PM fiber 
			pigtails, 50/50 split ratio in the slow axes of PM fibers and with super FC/PC connectors on all 
			ports.</td>
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			<td height="43" style="height:43px;width:216px;">Fiber holder</td>
			<td style="width:71px;">Thorlabs</td>
			<td style="width:119px;">T711/M-250</td>
			<td style="width:167px;">Metric, Post-Mountable Fiber Clamp, 250 &#181;m&#160;</td>
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			<td height="43" style="height:43px;width:216px;">Agar for microbiology</td>
			<td style="width:71px;">Sigma Aldrich</td>
			<td style="width:119px;">05039-500G</td>
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			<td height="64" style="height:64px;width:216px;">Nano-second pulse laser used for generating the optoacoustic signals</td>
			<td style="width:71px;">Opotek</td>
			<td style="width:119px;">VIBRANT Arrow 532 type I</td>
			<td style="width:167px;"></td>
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			<td height="43" style="height:43px;width:216px;">Graphite rod</td>
			<td style="width:71px;">&#160;Faber-Castell</td>
			<td style="width:119px;">120700</td>
			<td style="width:167px;">Faber-Castell Pencil Leads - 0.7 mm</td>
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wideband optical detector of ultrasound for medical imaging applications

最近、光音響イメージングの分野において実証されているように、超音波の光学センサは、圧電技術に対する有望な代替物である。医療用途では、光センシング技術の主要な制限の一つは、検出を飽和得る圧力及び温度の変化、例えば 、環境条件に対するその感受性である。さらに、臨床環境は、多くの場合、センサーの大きさと堅牢性に厳しい制限を課している。本研究では、パルス干渉とファイバベースの光検出との組み合わせは、超音波検出のために示されている。全ファイバ技術の使用は、高度な血管内イメージングなどの医療要求の厳しいアプリケーションに対応して、機械的に柔軟性の検出素子につながるのに対し、パルス干渉法は、環境条件の急激な変化の存在下で、読み出しシステムの堅牢な性能を可能にします。 、短いセンサ長を達成するためにπ位相シフトファイバブラッググレーティングは350ミクロンの有効長さにわたって光をトラップ共振器として作用するために使用される。高帯域幅を有効にするには、センサーは、血管内イメージングなどの周イメージングジオメトリにおいて非常に有益である超音波の横向きの検出に使用されます。光音響イメージング設定は、異なる位置での音響点源のためのセンサの応答を決定するために使用される。

図4aおよび4bは 、それぞれ、π-FBGの中心から三オフセットの繊維から1mmの距離で微視的球体からの信号と、それらに対応するスペクトルを示す。オフセットは、図3に示すように、zの方向に示されている。明らかに、高周波数超音波（fは&gt; 6メガヘルツ）、光検出器の感度は、異方性であり、π-FBGの中心を直接顕微鏡球上である場合に最も高く。シリカ?...

Watch this Scientific Journal Video about Wideband Optical Detector of Ultrasound for Medical Imaging Applications at JoVE.com

Wideband Optical Detector of Ultrasound for Medical Imaging Applications

それは多くの場合、安定した環境条件を必要とするため、超音波の光学的検出は、多くの画像化シナリオでは非現実的である。私たちは、制限的なシナリオでの光音響イメージングのための適切な小型化と感度レベルを持つ揮発性環境における超音波の検知のための光学技術、 例えば 、血管内のアプリケーションを示しています。

医療画像処理アプリケーションのための超音波の広帯域光検出器

Optical sensors of ultrasound are a promising alternative to piezoelectric techniques, as has been recently demonstrated in the field of optoacoustic ...

wideband-optical-detector-ultrasound-for-medical-imaging

Research

JoVE Journal

Bioengineering

10.7K ビュー.  Technical University of Munich and Helmholtz Center Munich. それは多くの場合、安定した環境条件を必要とするため、超音波の光学的検出は、多くの画像化シナリオでは非現実的である。私たちは、制限的なシナリオでの光音響イメージングのための適切な小型化と感度レベルを持つ揮発性環境における超音波の検知のための光学技術、 例えば 、血管内のアプリケーションを示しています。 

ビデオ: Wideband Optical Detector of Ultrasound for Medical Imaging Applications

Three-dimensional Optical-resolution Photoacoustic Microscopy

Optical microscopy, providing valuable insights at the cellular and organelle levels, has been widely recognized as an enabling biomedical technology. As the mainstays of in vivo three-dimensional (3-D) optical microscopy, single-/multi-photon fluorescence microscopy and optical coherence tomography (OCT) have demonstrated their extraordinary sensitivities to fluorescence and optical scattering contrasts, respectively. However, the optical absorption contrast of biological tissues, which encodes essential physiological/pathological information, has not yet been assessable. 
The emergence of biomedical photoacoustics has led to a new branch of optical microscopy optical-resolution photoacoustic microscopy (OR-PAM)1, where the optical irradiation is focused to the diffraction limit to achieve cellular1 or even subcellular2 level lateral resolution. As a valuable complement to existing optical microscopy technologies, OR-PAM brings in at least two novelties. First and most importantly, OR-PAM detects optical absorption contrasts with extraordinary sensitivity (i.e., 100%). Combining OR-PAM with fluorescence microscopy3 or with optical-scattering-based OCT4 (or with both) provides comprehensive optical properties of biological tissues. Second, OR-PAM encodes optical absorption into acoustic waves, in contrast to the pure optical processes in fluorescence microscopy and OCT, and provides background-free detection. The acoustic detection in OR-PAM mitigates the impacts of optical scattering on signal degradation and naturally eliminates possible interferences (i.e., crosstalks) between excitation and detection, which is a common problem in fluorescence microscopy due to the overlap between the excitation and fluorescence spectra. 
Unique for optical absorption imaging, OR-PAM has demonstrated broad biomedical applications since its invention, including, but not limited to, neurology5, 6, ophthalmology7, 8, vascular biology9, and dermatology10. In this video, we teach the system configuration and alignment of OR-PAM as well as the experimental procedures for in vivo functional microvascular imaging.

Optical-resolution photoacoustic microscopy (OR-PAM) is an emerging technology capable of imaging optical absorption contrasts in vivo with cellular resolution and sensitivity. Here, we provide a visualized instruction on the experimental protocols of OR-PAM, including system configuration, system alignment, typical in vivo experimental procedures, and functional imaging schemes.

三次元光学分解能光音響顕微鏡

Optical microscopy, providing valuable insights at the cellular and organelle levels, has been widely recognized as an enabling biomedical technology. As ...

生物工学

Optical Frequency Domain Imaging of Ex vivo Pulmonary Resection Specimens: Obtaining One to One Image to Histopathology Correlation

Lung cancer is the leading cause of cancer-related deaths1. Squamous cell and small cell cancers typically arise in association with the conducting airways, whereas adenocarcinomas are typically more peripheral in location. Lung malignancy detection early in the disease process may be difficult due to several limitations: radiological resolution, bronchoscopic limitations in evaluating tissue underlying the airway mucosa and identifying early pathologic changes, and small sample size and/or incomplete sampling in histology biopsies. High resolution imaging modalities, such as optical frequency domain imaging (OFDI), provide non-destructive, large area 3-dimensional views of tissue microstructure to depths approaching 2 mm in real time (Figure 1)2-6. OFDI has been utilized in a variety of applications, including evaluation of coronary artery atherosclerosis6,7 and esophageal intestinal metaplasia and dysplasia6,8-10.
Bronchoscopic OCT/OFDI has been demonstrated as a safe in vivo imaging tool for evaluating the pulmonary airways11-23 (Animation). OCT has been assessed in pulmonary airways16,23 and parenchyma17,22 of animal models and in vivo human airway14,15. OCT imaging of normal airway has demonstrated visualization of airway layering and alveolar attachments, and evaluation of dysplastic lesions has been found useful in distinguishing grades of dysplasia in the bronchial mucosa11,12,20,21. OFDI imaging of bronchial mucosa has been demonstrated in a short bronchial segment (0.8 cm)18. Additionally, volumetric OFDI spanning multiple airway generations in swine and human pulmonary airways in vivo has been described19. Endobronchial OCT/OFDI is typically performed using thin, flexible catheters, which are compatible with standard bronchoscopic access ports. Additionally, OCT and OFDI needle-based probes have recently been developed, which may be used to image regions of the lung beyond the airway wall or pleural surface17.
While OCT/OFDI has been utilized and demonstrated as feasible for in vivo pulmonary imaging, no studies with precisely matched one-to-one OFDI:histology have been performed. Therefore, specific imaging criteria for various pulmonary pathologies have yet to be developed. Histopathological counterparts obtained in vivo consist of only small biopsy fragments, which are difficult to correlate with large OFDI datasets. Additionally, they do not provide the comprehensive histology needed for registration with large volume OFDI. As a result, specific imaging features of pulmonary pathology cannot be developed in the in vivo setting. Precisely matched, one-to-one OFDI and histology correlation is vital to accurately evaluate features seen in OFDI against histology as a gold standard in order to derive specific image interpretation criteria for pulmonary neoplasms and other pulmonary pathologies. Once specific imaging criteria have been developed and validated ex vivo with matched one-to-one histology, the criteria may then be applied to in vivo imaging studies. Here, we present a method for precise, one to one correlation between high resolution optical imaging and histology in ex vivo lung resection specimens. Throughout this manuscript, we describe the techniques used to match OFDI images to histology. However, this method is not specific to OFDI and can be used to obtain histology-registered images for any optical imaging technique. We performed airway centered OFDI with a specialized custom built bronchoscopic 2.4 French (0.8 mm diameter) catheter. Tissue samples were marked with tissue dye, visible in both OFDI and histology. Careful orientation procedures were used to precisely correlate imaging and histological sampling locations. The techniques outlined in this manuscript were used to conduct the first demonstration of volumetric OFDI with precise correlation to tissue-based diagnosis for evaluating pulmonary pathology24. This straightforward, effective technique may be extended to other tissue types to provide precise imaging to histology correlation needed to determine fine imaging features of both normal and diseased tissues.

Optical Frequency Domain Imaging of Ex vivo Pulmonary Resection Specimens: Obtaining One to One Image to Histopathology Correlation

A method to image ex vivo pulmonary resection specimens with optical frequency domain imaging (OFDI) and obtain precise correlation to histology is described, which is essential to developing specific OFDI interpretation criteria for pulmonary pathology. This method is applicable to other tissue types and imaging techniques to obtain precise imaging to histology correlation for accurate image interpretation and assessment. Imaging criteria established with this technique would then be applicable to image assessment in future in vivo studies.

の光周波数領域イメージング<em&gt;エクスビボ</em&gt;肺切除標本：組織病理相関へのOne to Oneイメージの入手

Lung cancer is the leading cause of cancer-related deaths1. Squamous cell and small cell cancers typically arise in association with the conducting ...

Preparation of Mica Supported Lipid Bilayers for High Resolution Optical Microscopy Imaging

Supported lipid bilayers (SLBs) are widely used as a model for studying membrane properties (phase separation, clustering, dynamics) and its interaction with other compounds, such as drugs or peptides. However SLB characteristics differ depending on the support used. 
Commonly used techniques for SLB imaging and measurements are single molecule fluorescence microscopy, FCS and atomic force microscopy (AFM). Because most optical imaging studies are carried out on a glass support, while AFM requires an extremely flat surface (generally mica), results from these techniques cannot be compared directly, since the charge and smoothness properties of these materials strongly influence diffusion. Unfortunately, the high level of manual dexterity required for the cutting and gluing thin slices of mica to the glass slide presents a hurdle to routine use of mica for SLB preparation. Although this would be the method of choice, such prepared mica surfaces often end up being uneven (wavy) and difficult to image, especially with small working distance, high numerical aperture lenses. Here we present a simple and reproducible method for preparing thin, flat mica surfaces for lipid vesicle deposition and SLB preparation. Additionally, our custom made chamber requires only very small volumes of vesicles for SLB formation. The overall procedure results in the efficient, simple and inexpensive production of high quality lipid bilayer surfaces that are directly comparable to those used in AFM studies.

We present a method of preparing mica supported lipid bilayers for high resolution microscopy. Mica is transparent and flat on an atomic scale, but rarely used in imaging because of handling difficulties; our preparation results in even deposition of the mica sheet, and reduces the material used in bilayer preparation.

マイカの製造は、高分解能光学顕微鏡イメージングのための脂質二重層をサポート

Supported lipid bilayers (SLBs) are widely used as a model for studying membrane properties (phase separation, clustering, dynamics) and its interaction ...

Biofunctionalized Prussian Blue Nanoparticles for Multimodal Molecular Imaging Applications

Multimodal, molecular imaging allows the visualization of biological processes at cellular, subcellular, and molecular-level resolutions using multiple, complementary imaging techniques. These imaging agents facilitate the real-time assessment of pathways and mechanisms in vivo, which enhance both diagnostic and therapeutic efficacy. This article presents the protocol for the synthesis of biofunctionalized Prussian blue nanoparticles (PB NPs) - a novel class of agents for use in multimodal, molecular imaging applications. The imaging modalities incorporated in the nanoparticles, fluorescence imaging and magnetic resonance imaging (MRI), have complementary features. The PB NPs possess a core-shell design where gadolinium and manganese ions incorporated within the interstitial spaces of the PB lattice generate MRI contrast, both in T1 and T2-weighted sequences. The PB NPs are coated with fluorescent avidin using electrostatic self-assembly, which enables fluorescence imaging. The avidin-coated nanoparticles are modified with biotinylated ligands that confer molecular targeting capabilities to the nanoparticles. The stability and toxicity of the nanoparticles are measured, as well as their MRI relaxivities. The multimodal, molecular imaging capabilities of these biofunctionalized PB NPs are then demonstrated by using them for fluorescence imaging and molecular MRI in vitro.

This protocol describes the synthesis of biofunctionalized Prussian blue nanoparticles and their use as multimodal, molecular imaging agents. The nanoparticles have a core-shell design where gadolinium or manganese ions within the nanoparticle core generate MRI contrast. The biofunctional shell contains fluorophores for fluorescence imaging and targeting ligands for molecular targeting.

マルチモーダル分子イメージングアプリケーションのためのBiofunctionalizedプルシアンブルーナノ粒子

Multimodal, molecular imaging allows the visualization of biological processes at cellular, subcellular, and molecular-level resolutions using multiple, ...

Real-time Monitoring of High Intensity Focused Ultrasound (HIFU) Ablation of In Vitro Canine Livers Using Harmonic Motion Imaging for Focused Ultrasound (HMIFU)

Harmonic Motion Imaging for Focused Ultrasound (HMIFU) is a technique that can perform and monitor high-intensity focused ultrasound (HIFU) ablation. An oscillatory motion is generated at the focus of a 93-element and 4.5 MHz center frequency HIFU transducer by applying a 25 Hz amplitude-modulated signal using a function generator. A 64-element and 2.5 MHz imaging transducer with 68kPa peak pressure is confocally placed at the center of the HIFU transducer to acquire the radio-frequency (RF) channel data. In this protocol, real-time monitoring of thermal ablation using HIFU with an acoustic power of 7 W on canine livers in vitro is described. HIFU treatment is applied on the tissue during 2 min and the ablated region is imaged in real-time using diverging or plane wave imaging up to 1,000 frames/second. The matrix of RF channel data is multiplied by a sparse matrix for image reconstruction. The reconstructed field of view is of 90&#176; for diverging wave and 20 mm for plane wave imaging and the data are sampled at 80 MHz. The reconstruction is performed on a Graphical Processing Unit (GPU) in order to image in real-time at a 4.5 display frame rate. 1-D normalized cross-correlation of the reconstructed RF data is used to estimate axial displacements in the focal region. The magnitude of the peak-to-peak displacement at the focal depth decreases during the thermal ablation which denotes stiffening of the tissue due to the formation of a lesion. The displacement signal-to-noise ratio (SNRd) at the focal area for plane wave was 1.4 times higher than for diverging wave showing that plane wave imaging appears to produce better displacement maps quality for HMIFU than diverging wave imaging.

Real-time Monitoring of High Intensity Focused Ultrasound HIFU Ablation of In Vitro Canine Livers Using Harmonic Motion Imaging for Focused Ultrasound HMIFU

This article describes real-time monitoring of HIFU ablation in canine liver with high frame rate ultrasound imaging using diverging and plane wave imaging. Harmonic Motion Imaging for Focused Ultrasound is used to image the decrease of acoustic radiation force induced displacement in the ablated region.

高強度のリアルタイムモニタリングの超音波（HIFU）アブレーションを重視しました<em&gt;インビトロ</em集束超音波のための調和運動イメージングの使用&gt;犬の肝臓（HMIFU）

Harmonic Motion Imaging for Focused Ultrasound (HMIFU) is a technique that can perform and monitor high-intensity focused ultrasound (HIFU) ablation. An ...

Computed Tomography and Optical Imaging of Osteogenesis-angiogenesis Coupling to Assess Integration of Cranial Bone Autografts and Allografts

A major parameter determining the success of a bone-grafting procedure is vascularization of the area surrounding the graft. We hypothesized that implantation of a bone autograft would induce greater bone regeneration by abundant blood vessel formation. To investigate the effect of the graft on neovascularization at the defect site, we developed a micro&#8211;computed tomography (&#181;CT) approach to characterize newly forming blood vessels, which involves systemic perfusion of the animal with a polymerizing contrast agent. This method enables detailed vascular analysis of an organ in its entirety. Additionally, blood perfusion was assessed using fluorescence imaging (FLI) of a blood-borne fluorescent agent. Bone formation was quantified by FLI using a hydroxyapatite-targeted probe and &#181;CT analysis. Stem cell recruitment was monitored by bioluminescence imaging (BLI) of transgenic mice that express luciferase under the control of the osteocalcin promoter. Here we describe and demonstrate preparation of the allograft, calvarial defect surgery, &#181;CT scanning protocols for the neovascularization study and bone formation analysis (including the in vivo perfusion of contrast agent), and the protocol for data analysis.
The 3D high-resolution analysis of vasculature demonstrated significantly greater angiogenesis in animals with implanted autografts, especially with respect to arteriole formation. Accordingly, blood perfusion was significantly higher in the autograft group by the 7th day after surgery. We observed superior bone mineralization and measured greater bone formation in animals that received autografts. Autograft implantation induced resident stem cell recruitment to the graft-host bone suture, where the cells differentiated into bone-forming cells between the 7th and 10th postoperative day. This finding means that enhanced bone formation may be attributed to the augmented vascular feeding that characterizes autograft implantation. The methods depicted may serve as an optimal tool to study bone regeneration in terms of tightly bounded bone formation and neovascularization.

Implantation of autologous and allogeneic bone grafts constitute accepted approaches to treat major craniofacial bone loss. Yet the effect of graft composition on the interplay among neovascularization, cell differentiation and bone formation is unclear. We present a multimodal imaging protocol aimed to elucidate the angiogenesis-osteogenesis interdependence at the graft proximity.

コンピュータ断層撮影法と頭蓋骨自家移植と同種移植片の統合を評価するために、骨形成、血管新生のカップリングの光イメージング

A major parameter determining the success of a bone-grafting procedure is vascularization of the area surrounding the graft. We hypothesized that ...

High-throughput Identification of Bacteria Repellent Polymers for Medical Devices

Medical devices are often associated with hospital-acquired infections, which place enormous strain on patients and the healthcare system as well as contributing to antimicrobial resistance. One possible avenue for the reduction of device-associated infections is the identification of bacteria-repellent polymer coatings for these devices, which would prevent bacterial binding at the initial attachment step. A method for the identification of such repellent polymers, based on the parallel screening of hundreds of polymers using a microarray, is described here. This high-throughput method resulted in the identification of a range of promising polymers that resisted binding of various clinically relevant bacterial species individually and also as multi-species communities. One polymer, PA13 (poly(methylmethacrylate-co-dimethylacrylamide)), demonstrated significant reduction in attachment of a number of hospital isolates when coated onto two commercially available central venous catheters. The method described could be applied to identify polymers for a wide range of applications in which modification of bacterial attachment is important.

A high-throughput microarray method for the identification of polymers which reduce bacterial surface binding on medical devices is described.

医療機器のための細菌撥ポリマーのハイスループット同定

Medical devices are often associated with hospital-acquired infections, which place enormous strain on patients and the healthcare system as well as ...

Medical-grade Sterilizable Target for Fluid-immersed Fetoscope Optical Distortion Calibration

We have developed a calibration target for use with fluid-immersed endoscopes within the context of the GIFT-Surg (Guided Instrumentation for Fetal Therapy and Surgery) project. One of the aims of this project is to engineer novel, real-time image processing methods for intra-operative use in the treatment of congenital birth defects, such as spina bifida and the twin-to-twin transfusion syndrome. The developed target allows for the sterility-preserving optical distortion calibration of endoscopes within a few minutes. Good optical distortion calibration and compensation are important for mitigating undesirable effects like radial distortions, which not only hamper accurate imaging using existing endoscopic technology during fetal surgery, but also make acquired images less suitable for potentially very useful image computing applications, like real-time mosaicing. In this paper proposes a novel fabrication method to create an affordable, sterilizable calibration target suitable for use in a clinical setup. This method involves etching a calibration pattern by laser cutting a sandblasted stainless steel sheet. This target was validated using the camera calibration module provided by OpenCV, a state-of-the-art software library popular in the computer vision community.

This article describes the design and development of a sterilizable custom camera optical distortion calibration target for the peri-operative, fluid-immersed calibration of endoscopes during endoscopic interventions.

流体浸漬胎児鏡光学歪み校正のための医療用滅菌可能なターゲット

We have developed a calibration target for use with fluid-immersed endoscopes within the context of the GIFT-Surg (Guided Instrumentation for Fetal ...

Long-term Live Imaging Device for Improved Experimental Manipulation of Zebrafish Larvae

The zebrafish larva is an important model organism for both developmental biology and wound healing. Further, the zebrafish larva is a valuable system for live high-resolution microscopic imaging of dynamic biological phenomena in space and time with cellular resolution. However, the traditional method of agarose encapsulation for live imaging can impede larval development and tissue regrowth. Therefore, this manuscript describes the zWEDGI (zebrafish Wounding and Entrapment Device for Growth and Imaging), which was designed and fabricated as a functionally compartmentalized device to orient larvae for high-resolution microscopy while permitting caudal fin transection within the device and subsequent unrestrained tail development and re-growth. This device allows for wounding and long-term imaging while maintaining viability. Given that the zWEDGI mold is 3D printed, the customizability of its geometries make it easily modified for diverse zebrafish imaging applications. Furthermore, the zWEDGI offers numerous benefits, such as access to the larva during experimentation for wounding or for the application of reagents, paralleled orientation of multiple larvae for streamlined imaging, and reusability of the device.

This manuscript describes the zWEDGI (zebrafish Wounding and Entrapment Device for Growth and Imaging), which is a compartmentalized device designed to orient and restrain zebrafish larvae. The design permits tail transection and long-term collection of high-resolution fluorescent microscopy images of wound healing and regeneration.

ゼブラフィッシュ幼虫の改良実験操作のための長期のライブ イメージング デバイス

The zebrafish larva is an important model organism for both developmental biology and wound healing. Further, the zebrafish larva is a valuable system for ...

Optical Imaging of Isolated Murine Ventricular Myocytes

The ability to isolate adult cardiac myocytes has permitted researchers to study a variety of cardiac pathologies at the single cell level. While advances in calcium sensitive dyes have permitted the robust optical recording of single cell calcium dynamics, recording of robust transmembrane optical voltage signals has remained difficult. Arguably, this is because of the low single to noise ratio, phototoxicity, and photobleaching of traditional potentiometric dyes. Therefore, single cell voltage measurements have long been confined to the patch clamp technique which while the gold standard, is technically demanding and low throughput. However, with the development of novel potentiometric dyes, large, fast optical responses to changes in voltage can be obtained with little to no phototoxicity and photobleaching. This protocol describes in detail how to isolate adult murine myocytes which can be used for cellular shortening, calcium, and optical voltage measurements. Specifically, the protocol describes how to use a ratiometric calcium dye, a single-excitation calcium dye, and a single excitation voltage dye. This approach can be used to assess the cardiotoxicity and arrhythmogenicity of various chemical agents. While phototoxicity is still an issue at the single cell level, methodology is discussed on how to reduce it.

We present the methodology for the isolation of murine myocytes and how to obtain voltage or calcium traces simultaneously with sarcomere shortening traces using fluorescence photometry with simultaneous digital cell geometry measurements.

単離マウス心室筋細胞の光学イメージング

The ability to isolate adult cardiac myocytes has permitted researchers to study a variety of cardiac pathologies at the single cell level. While advances ...