Peroxides as "switches" of dialkyl H-phosphonate: two mild and metal-free methods for preparation of 2-acylbenzothiazoles and dialkyl benzothiazol-2-ylphosphonates.

Two mild and metal-free methods for the preparation of two kinds of important benzothiazole derivatives, 2-acylbenzothiazoles and dialkyl benzothiazol-2-ylphosphonates, respectively, were developed. The dialkyl H-phosphonate (RO)2P(O)H exists in equilibrium with its tautomer dialkyl phosphite (RO)2POH. TBHP triggered α-carbon-centered phosphite radical formation, whereas DTBP triggered phosphorus-centered phosphonate radical formation. The two types of radicals led respectively to two different reaction processes, the direct C2-acylation of benzothiazoles and C2-phosphonation of benzothiazoles.

Acquisition of thin coronal sectional dataset of cadaveric liver.

PURPOSE: To obtain the thin coronal sectional anatomic dataset of the liver by using digital freezing milling technique. METHODS: The upper abdomen of one Chinese adult cadaver was selected as the specimen. After CT and MRI examinations verification of absent liver lesions, the specimen was embedded with gelatin in stand erect position and frozen under profound hypothermia, and the specimen was then serially sectioned from anterior to posterior layer by layer with digital milling machine in the freezing chamber. The sequential images were captured by means of a digital camera and the dataset was imported to imaging workstation. RESULTS: The thin serial section of the liver added up to 699 layers with each layer being 0.2 mm in thickness. The shape, location, structure, intrahepatic vessels and adjacent structures of the liver was displayed clearly on each layer of the coronal sectional slice. CT and MR images through the body were obtained at 1.0 and 3.0 mm intervals, respectively. CONCLUSION: The methodology reported here is an adaptation of the milling methods previously described, which is a new data acquisition method for sectional anatomy. The thin coronal sectional anatomic dataset of the liver obtained by this technique is of high precision and good quality.

The thin sectional anatomy of the sellar region with MRI correlation.

The purpose of this study was to explore the anatomical complexity and adjacent relationships of the sellar region in thin continuous sections so as to provide intimate morphological data for imaging diagnosis and surgical operations of the diseases in this region. After CT and MR examination verifying no brain lesions, one normal cadaver head was selected for this study from four Chinese adult male cadavers. After being embedded and frozen, the head was sliced into serial sections at 0.1 mm intervals in the transverse plane with SKC 500 computerized freezing milling machine. Then the serial transverse sections were photographed by a high-resolution digital camera and saved in the computer. Subsequently, the anatomic structures of the sellar region on the thin transverse sections were investigated and correlated with the MR images of the specimen as well as in vivo MR images, which were obtained from 20 normal Chinese male adult volunteers by a 3.0 T GE MR scanner. The base lines of the sectioning and the MR scan were all parallel to the AC-PC line. A total of 320 transverse sections and 10-12 transverse MR images related with the sellar region were obtained, respectively. We investigated the sectional anatomy of the sellar region and divided it into three parts: supra hypophysial area, hypophysial area and infra hypophysial area. The cavernous sinus was a venous passage full of blood and it could be divided into four interspaces according to its position relation with the internal carotid artery. The third, fourth, sixth cranial nerves and trigeminal branches ophthalmic nerve, maxillary nerve displayed from the anterior to the posterior in the lateral wall of cavernous sinus in transverse planes. Comparing continuous thin sections with MR images offers a better understanding of the complex anatomical structures and provides practical submillimeter anatomical data for imaging diagnosis and clinical treatment in this region.

Segmentation and reconstruction of hepatic veins and intrahepatic portal vein based on the coronal sectional anatomic dataset.

Three-dimensional (3D) reconstruction of intrahepatic vessels is very useful in visualizing the complex anatomy of hepatic veins and intrahepatic portal vein. It also provides a 3D anatomic basis for diagnostic imaging and surgical operation on the liver. In the present study, we built a 3D digitized model of hepatic veins and intrahepatic portal vein based on the coronal sectional anatomic dataset of the liver. The dataset was obtained using the digital freezing milling technique. The pre-reconstructed structures were identified and extracted, and then were segmented by the method of manual intervention. The digitized model of hepatic veins and intrahepatic portal vein was established using 3D medical visualization software. This model facilitated a continuous and dynamic displaying of the hepatic veins and intrahepatic portal vein at different orientations, which demonstrated the complicated relationship of adjacent hepatic veins and intrahepatic portal vein realistically in the 3D space. This study indicated that high-quality 2D images, precise data segmentation, and suitable 3D reconstruction methods ensured the reality and accuracy of the digital visualized model of hepatic veins and intrahepatic portal vein.

The pineal region: thin sectional anatomy with MR correlation in the coronal plane.

This study was undertaken to explore the anatomic features and adjacent relationships of the pineal region in thin coronal sections. After CT and MR examination verifying no brain lesions, one normal cadaver head was selected for this study from three Chinese adult male cadavers. After being embedded and frozen, the head was sliced into serial sections at 0.1 mm intervals in the coronal plane with SKC 500 computerized freezing milling machine. Then the serial coronal sections were photographed by a high-resolution digital camera and saved in the computer. Subsequently, the anatomic structures of the pineal region on the thin coronal sections were investigated and correlated with in vivo MR images, which were obtained from ten normal Chinese male adult volunteers by a 3.0 T GE scanner. The base lines of the sectioning and the MR scan were all perpendicular to the AC-PC line. A total of 355 coronal sections and 21-23 in vivo coronal MR images related with the pineal region were obtained, respectively. From anterior to posterior, the shape of the pineal region changed from an inverted triangle to a trapezoid and a triangle gradually, and the anatomic details could be depicted clearly in the thin sectional anatomy images in sub-millimeter. Via the comparison, some micro-anatomic structures of the pineal region that cannot be discriminated clearly or missed in the thick sections or MR images were identified. The contrast of the computerized freezing milling technique with the MRI enhanced our ability to comprehend the complex anatomy of the pineal region and to improve the imaging diagnosis and surgical treatments of minute diseases in this region.

Sectional anatomy of the adrenal gland in the coronal plane.

To provide practical anatomic data for the imaging diagnosis and surgical treatment of adrenal disease, we investigated the anatomy of the adrenal gland and its relationships to regional structures using 31 sets of serial coronal sections of upper abdomen of Chinese adult cadavers and correlated coronal magnetic resonance (MR) images of ten upper abdomens of adult healthy volunteers and coronal reconstructed multislice spiral computed tomography (MSCT) images of five patients without lesions in the adrenal gland. The adrenal glands were visualized mainly on the successive coronal sections between 18 mm anterior to the posterior margin of inferior vena cava and 24 mm posterior to the posterior margin of inferior vena cava. In general, the left adrenal gland was visualized two sections earlier than the right adrenal gland. On the plane through the anterior parts of bilateral renal hili (A18), the appearance rate of bilateral adrenal glands was 100%, and the maximal measurements of bilateral adrenal glands were visualized. The length, width, thickness of right adrenal body, thickness of medial limb and lateral limb were, respectively, 34.02 +/- 2.12 mm, 10.91 +/- 0.89 mm, 5.82 +/- 0.26 mm, 2.78 +/- 0.08 mm, 2.62 +/- 0.06 mm, whereas the measurements of left adrenal gland were 28.31 +/- 2.46 mm, 18.40 +/- 1.06 mm, 6.84 +/- 0.24 mm, 3.02 +/- 0.08 mm, 2.86 +/- 0.07 mm, respectively. The coronal plane has superior advantage in showing the bilateral adrenal glands. The shapes of adrenal glands are various, whereas the range of adrenal thickness is quite narrow. The thickness of adrenal medial and lateral limbs, especially the thickness of lateral limb are useful for the diagnosis of the bilateral adrenocortical disease.