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J Noordzij

Publications and source records attributed to J Noordzij.

8 recordsLinked to original sources

[Towards safer and parenchyma-conserving liver resections: experience with three-dimensional reconstructions of spiral CT scan].

New techniques are available for the diagnosis and treatment of liver metastases. Three patients, a male aged 52 and two females aged 70 and 47, developed liver metastases after resection of a colorectal carcinoma. Spiral CT scanning made possible detailed three dimensional imaging of the liver to determine the extension of the metastases and the site of the metastasis in relation to blood vessels and bile ducts. This enabled the surgeon preoperatively to arrive at a balanced operation strategy, with the objectives of radical resection of the metastasis and conservation of sufficient residual liver tissue with minimal morbidity and mortality. In addition, use was made of peroperative clamping of blood vessels to determine the possibility of resecting along anatomical borders. This offers the advantages that less blood is lost and a smaller resection often suffices. In the 3 patients followed respectively a wedge excision of the tumour, a wedge excision combined with a hemihepatectomy and a resection of two segments.

Adenocarcinoma↗

Preferential rearrangements of the T cell receptor-delta-deleting elements in human T cells.

The major part of the TCR-delta locus is flanked by the so-called TCR-delta-deleting elements deltaRec and psi(J)alpha, which preferentially rearrange to each other in human thymocytes. On the basis of our combined Southern blot and PCR analyses, we also identified the prominent deltaRec-Jalpha58 rearrangement and three other preferential deltaRec rearrangements. The latter rearrangements concern deltaRec rearrangements to the Ddelta3, Jdelta1, and Jdelta3 gene segments. These deltaRec rearrangements do not delete the complete TCR-delta locus and are homologous to Vdelta-Jdelta rearrangements, because the majority of their junctional regions contain Ddelta gene segments. In contrast, the prominent deltaRec-psi(J)alpha and deltaRec-Jalpha58 rearrangements, representing approximately 68 and approximately 23% of all deltaRec rearrangements, respectively, are homologous to Valpha-Jalpha rearrangements, because Ddelta gene segments are absent in their junctional regions. Additional PCR analysis of Vdelta-psi(J)alpha and Vdelta-Jalpha58 coding and signal joints revealed also that these rearrangements resemble Valpha-Jalpha rearrangements, except for Vdelta2-psi(J)alpha and Vdelta2-Jalpha58 rearrangements, which resemble Vdelta-Jdelta rearrangements. Our data show that virtually all TCR-delta-deleting rearrangements are Valpha-like, and the high frequency of these rearrangements in the human thymus suggests that most thymocytes use these rearrangements to further differentiate into the TCR-alphabeta lineage. Based on the very low frequency of deltaRec and psi(J)alpha rearrangements in 4% of the T cell acute lymphoblastic leukemia patients (n = 151) and 6% of the T cell lines (n = 26), we hypothesize that rearranged TCR-delta-deleting elements exist for only an extremely short period during thymocyte differentiation, probably due to rapid subsequent Valpha-Jalpha rearrangements.

Alleles↗

Focal liver lesions: characterization with triphasic spiral CT.

PURPOSE: To assess whether triphasic spiral CT enables characterization of a wide range of focal liver lesions. MATERIALS AND METHODS: One hundred five patients with suspected focal liver disease underwent triphasic liver CT. After injection of contrast material, the liver was scanned in arterial (scanning delay, 22-27 seconds), portal (scanning delay, 49-73 seconds), and equilibrium (scanning delay, 8-10 minutes) phases. Enhancement of each lesion in each phase was evaluated, and the lesions were tabulated according to one of 11 enhancement patterns. RESULTS: In 94 patients, 375 liver lesions were detected. The nature of the lesion was confirmed in 326 lesions (87%). Six of 11 enhancement patterns were always due to benign disease and caused by areas with hyper- or hypoperfusion, hemangiomas, cysts, focal nodular hyperplasias, or benign but nonspecified lesions. Two of 11 patterns were always due to malignant disease, and one pattern was due to malignant disease in 38 (97%) of 39 patients with known malignancy elsewhere or with chronic liver disease. The other two patterns were seen in metastases and partly fibrosed hemangiomas. CONCLUSION: Triphasic liver CT enables characterization of a wide range of focal liver lesions, including the benign liver lesions that occur most frequently.

Adult↗

Adenomatous polyposis coli gene mutations in ulcerative colitis-associated dysplasias and cancers versus sporadic colon neoplasms.

Adenomatous polyposis coli (APC) gene mutations occur in most sporadic colonic adenomas and carcinomas. Precursor lesions of ulcerative colitis (UC)-associated colon carcinomas, although morphologically similar to sporadic adenomas, may be biologically distinct from them and are, in fact, managed differently. Since sporadic adenomas may also occur in UC, a method of discriminating between these forms of neoplasia could have clinical utility. We examined 33 patients with UC-associated dysplasias and cancers and 23 sporadic colon neoplasms in a side-by-side comparison for APC mutations. Codons 686-1693, containing 64% of all reported APC mutations (the mutation cluster region), were screened for truncating mutations using an in vitro synthesized protein assay. Two of thirty-three patients (6%) with UC-associated dysplasias and cancers had a total of three truncating APC mutations, all in frank carcinomas, while 17 of 23 (74%) with sporadic colonic neoplasms had mutations. DNA sequencing confirmed two mutations in codon 1460, replacing arginine with a stop codon, as well as one 2-base pair deletion, resulting in a frameshift and a stop at codon 1477. One specimen contained one each of these APC mutations. This apparent contrast in mutation rates at the mutation cluster region of APC is consistent with other biological characteristics separating sporadic colon neoplasms from UC-associated dysplasias and cancers. These data raise the possibility that nonadenomatous UC dysplasias may arise by a molecular pathway distinct from that prevailing in sporadic colon carcinogenesis, and they suggest a molecular assay to discriminate between sporadic adenomas and dysplasias occurring in UC.

Base Sequence↗

Spiral CT-angiography of the aorta.

AIMS: To determine whether the new technique of CT-angiography was accurate in displaying the complex anatomy of the aorta and its major branches. METHODS: Seventeen patients with a variety of aortic pathology were examined. Using a spiral CT-scanner a volumetric scan was made during injection of 150 cc of i.v. contrast. Depending on the chosen CT technique, a body volume with a length ranging between 25-100 cm could be examined in one 50 second spiral scan. On the resulting transverse slices vascular lumina and extent of thrombus were studied. Subsequently, the transverse slices were reconstructed in the coronal or sagittal plane in order to appreciate the craniocaudal relations of the vascular anatomy. Finally, three-dimensional reconstructions were made of vascular lumina and thrombus. RESULTS: In aortic aneurysms the extent of the aneurysmal dilatation and of the adherent thrombus could be accurately located relative to the origins of renal and visceral branches proximally, and iliac bifurcation distally. In cases of severe elongation, dissection or complex anatomy, a detailed preoperative insight into the individual anatomy could be obtained. The two-dimensional axial and multiplanar reconstructions offered excellent anatomic detail. The three-dimensional reconstructions, being based on a considerable data reduction, offered an efficient means of providing an overall view of complex anatomic relations. CONCLUSION: The advantage of CT-angiography is that, based on a single spiral scan, the vascular structures in the examined body volume can be displayed in any desired plane using multiplanar reconstructions. Alternatively, three-dimensional renderings can be created. The combination of multiplanar reconstructions and three-dimensional reconstructions makes CT-angiography an accurate technique for displaying even the most complex aortic anatomy.

Aortic Dissection↗

Portal venous and segmental anatomy of the right hemiliver: observations based on three-dimensional spiral CT renderings.

OBJECTIVE: The purpose of this study was to evaluate the segmental anatomy of the right hemiliver and to assess whether the right hepatic vein and right portal trunk are accurate indicators of the position of the right and transverse scissurae, respectively. SUBJECTS AND METHODS: We examined 26 patients with spiral CT using 5-mm slices, reconstructed at 2-mm intervals. Three-dimensional renderings of the portal and hepatic venous structures were created. The portal ramification pattern and relationship between the hepatic veins and portal system were evaluated. RESULTS: In the right hemiliver, an anterosuperior sector and a posteroinferior sector were present in all patients. In addition, in nine patients, a total of 15 accessory portal sectors were present, each arising directly from the portal bifurcation or the right portal trunk. Further subdivision of the portal sectors showed marked individual variability, with no prevailing branching pattern. The scissura between the anterosuperior and posteroinferior sectors showed an angled orientation--its cranial part was tilted posteriorly (average, 58.4 degrees) and its caudal part was tilted anteriorly (average, 2.8 degrees)--relative to the coronal plane. In 24 patients, portal branches crossed the plane of the right hepatic vein. No transverse scissura could be seen in the anterosuperior or posteroinferior sector. CONCLUSION: The right hemiliver could be divided into anterosuperior and posteroinferior sectors in all patients studied. Many patients have accessory sectors. Further subdivision into portal segments can be described only after the individual portal branching pattern has been studied. The right hepatic vein is an inaccurate indicator of the position of the right scissura. No clear transverse scissura can be seen in the right hemiliver.

Adult↗

Planning of liver surgery using three dimensional imaging techniques.

In the simplified Couinaud classification, in which the liver is divided into eight segments, each supplied by a central vasculo-biliary sheath, little attention is given to the high prevalence of anatomical variations which occur, especially in the right hemiliver. Using volumetric acquisition techniques, such as magnetic resonance imaging or spiral computed tomography scanning, detailed insight into the individual segmental anatomy can now be obtained in a non-invasive manner. The significance of this anatomical insight lies in the planning of anatomical resections, whereby the relationship between tumour and individual segmental anatomy can be depicted in a three-dimensional format. As such, three dimensional (3D) liver imaging helps to design an individualised resection, tailored to the topographical relationship between individual segmental anatomy and tumour tissue present. Three dimensional liver imaging is of most practical value if a resection of one or more segments or sectors is considered, especially in the right hemiliver. In these cases, 3D liver imaging can demonstrate the precise location of the scissuras to the surgeon pre-operatively.

Colorectal Neoplasms↗