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PURPOSE: The aim of this study was to evaluate the feasibility and the accuracy of a secondary, metachronous ultrasound (US)-guided marking of the stereotactic vacuum-assisted breast biopsy (ST-VABB) area. MATERIALS AND METHODS: The institutional ethics committee approved the study. The retrospective study included 98 patients. In ST-VABB of 45 women, no tissue markers were deployed at the biopsy site, even if no residual calcifications remained. After histology proved the necessity for a subsequent operation, the biopsy site was marked under US guidance using a coil marker. All interventions were technically successful. No complications occurred. Mammography was done to visualize the coil deployment. The distances from the center of the lesion and the biopsy cavity to the coil location were measured in both planes to evaluate the accuracy of the marking procedure. RESULTS: In 24 of the 46 cases, the whole lesion was biopsied without residual elements. The mean time between ST-VABB and sonographic marking of the lesion was 9.7 days (median 6.5). The biopsy cavity could be detected in 40 (87%) cases and thus marked exactly. The mean time of US-guided marking was 12.5 min. The mean distance between the coil and the target lesion was 0.6 ± 1.5 cm in the craniocaudal (cc) view and 0.5 ± 1.5 cm in the mediolateral (ml) view for all markings. The mean delta value from the distance nipple-original lesion and from the distance nipple-coil was 0.85 ± 1.2 cm (median 0.5) in the cc view and 0.88 ± 1.2 cm (median 0.6) in the ml view for all cases. Clip migration was not observed. CONCLUSION: Our study demonstrates the feasibility and the technical success of secondary metachronous coil marking of the biopsy site under US guidance after receipt of histology. This approach seems to be a cost-effective alternative to the standard procedure of the primary coil marking especially in all completely removed lesions. It may offer advantages for allergic patients.

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Determination of protein function requires tools that allow its detection and/or purification. As generation of specific antibodies often is laborious and insufficient, protein tagging using epitopes that are recognized by commercially available antibodies and matrices appears more promising. Also, proper spatial and temporal expression of tagged proteins is required to prevent falsification of results. We developed a new series of binary Gateway cloning vectors named pAUL1-20 for C- and N-terminal in-frame fusion of proteins to four different tags: a single (i) HA epitope and (ii) Strep-tagIII, (iii) both epitopes combined to a double tag, and (iv) a triple tag consisting of the double tag extended by a Protein A tag possessing a 3C protease cleavage site. Expression can be driven by either the 35 S CaMV promoter or, for C-terminal fusions, promoters from genes encoding the chloroplast biogenesis factors HCF107, HCF136, or HCF173. Fusions of the four promoters to the GUS gene showed that endogenous promoter sequences are functional and drive expression more moderately and consistently throughout different transgenic lines when compared to the 35 S CaMV promoter. By testing complementation of mutations affected in chloroplast biogenesis factors HCF107 and HCF208, we found that the effect of different promoters and tags on protein function strongly depends on the protein itself. Single-step and tandem affinity purification of HCF208 via different tags confirmed the integrity of the cloned tags.

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The related proteins D1 and D2 together build up the photosystem II reaction center. Synthesis of D1 (PsbA) is highly regulated in all photosynthetic organisms. The mechanisms and specific protein factors involved in controlled expression of the psbA gene in higher plants are highly elusive. Here, we report on the identification of a chloroplast-located protein, HCF244 (for high chlorophyll fluorescence244), which is essentially required for translational initiation of the psbA messenger RNA in Arabidopsis (Arabidopsis thaliana). The factor is highly conserved between land plants, algae, and cyanobacteria. HCF244 was identified by coexpression analysis of HCF173, which encodes a protein that is also necessary for psbA translational initiation and in addition for stabilization of this messenger RNA. Phenotypic characterization of the mutants hcf244 and hcf173 suggests that the corresponding proteins operate cooperatively during psbA translation. Immunolocalization studies detected the majority of the two proteins at the thylakoid membrane. Both HCF244 and HCF173 are members of the atypical short-chain dehydrogenase/reductase superfamily, a modified group, which has lost enzyme activity but acquires new functions in the metabolism of the cell.

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BACKGROUND: The prognosis for patients with liver metastases from colorectal carcinoma is limited because of the low number of patients who are eligible for curative hepatic resection. In this phase I study, 31 liver metastases in 24 patients with nonresectable metastases from colorectal carcinoma were treated with photodynamic therapy (PDT). METHODS: The photosensitizer 5,10,15,20-tetrakis(m-hydroxyphenyl)bacteriochlorin (mTHPBC) was intravenously administered in a dose of .6 mg/kg (n = 12) or .3 mg/kg (n = 12). After 120 hours (n = 18) or 48 hours (n = 6), tumors were illuminated for 300 to 600 seconds through percutaneously inserted optical fibers with a light dose of 60 J/cm of diffuser (740 nm). RESULTS: Tumor necrosis at 1 month after PDT was achieved in all treated lesions. Laser treatment was associated with mild pain (n = 8) and transient subclinical hepatotoxicity (n = 21). In one patient, PDT damage to the pancreas was inflicted, and in another patient, PDT damage of the skin occurred, but no serious clinical complications from PDT were reported. Administration of .6 mg/kg of mTHPBC led to transient phlebitis in 10 patients, and 3 patients experienced mild skin phototoxicity after excess light exposure. CONCLUSIONS: Colorectal liver metastases that are ineligible for resection can be safely and effectively treated with interstitial mTHPBC-based PDT.

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The purpose of this study was to examine the feasibility and safety of MR-guided biopsies with a transgluteal approach in patients with uncertain or suspicious prostate lesions. Twenty-five patients with uncertain or suspicious focal prostate lesions detected by high-field MR imaging of the prostate gland using endorectal coil imaging were biopsied with a transgluteal approach in a low-field MRI system (0.2 T, Concerto, Siemens). The procedures were guided using T1-weighted FLASH sequences. The prostate gland was biopsied repeatedly with a coaxial technique through a 15-gauge pencil tip with a 16-gauge biopsy handy (median 3.8 samples per patient). Complications and biopsy findings were documented retrospectively. Using T1-weighted sequences biopsy procedures were performed successfully with MR guidance in all cases without any side effects or complications. The median intervention time was 11.3 min. Pathological findings revealed ten cases of hyperplasia or atrophy, three cases of prostatitis, ten cases of carcinoma and two cases of normal tissue. The clinical follow-up showed that in two patients prostate cancer was missed at MR-guided biopsy. Transgluteal MR-guided biopsy of the prostate gland is a safe and promising approach for histological clarification of uncertain or suspicious lesions.

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Photodynamic therapy (PDT) is a well-investigated locoregional cancer treatment in which a systemically administered photosensitizer is activated locally by illuminating the diseased tissue with light of a suitable wavelength. PDT offers various treatment strategies in oncology, especially palliative ones. This article focuses on the development and evaluation of interstitial PDT for the treatment of solid tumors, particularly liver tumors. The PDT is mostly used for superficial and endoluminal lesions like skin or bladder malignancies and also more frequently applied for the treatment of lung, esophageal, and head and neck cancer. With the help of specially designed application systems, PDT is now becoming a practicable option for solid lesions, including those in parenchymal organs such as the liver. After intravenous treatment with the photosensitizer followed by interstitial light activation, contrast-enhanced computed tomography shows the development of therapy-induced necrosis around the light-guiding device. With the use of multiple devices, ablation of liver tumors seems to be possible, and no severe side effects or toxicities related to the treatment are reported. PDT can become a clinically relevant adjunct in the locoregional therapy strategies.

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PURPOSE: To evaluate a treatment protocol with repeated transarterial chemoembolization (TACE) before laser-induced thermotherapy (LITT) in patients with unresectable liver metastases that are too large for LITT alone. MATERIALS AND METHODS: One hundred sixty-two patients who had unresectable liver metastases, with the largest lesion as large as 80 mm in diameter, and no more than four lesions were treated with repeated TACE between March 1999 and December 2001. TACE was performed with a maximum of 10 mg/m2 mitomycin for chemotherapy and a maximum of 15 mL/m2 of iodized oil and microspheres for vessel occlusion. Tumor volume before and during treatment was measured at magnetic resonance (MR) imaging. If the diameter of the tumor decreased to less than 50 mm, the patients were treated with MR imaging-guided LITT 4-6 weeks following embolization. RESULTS: Eighty-two patients (62 with metastases from colorectal cancer, 14 with metastases from breast cancer, and six with metastases from other primary tumors) responded to TACE, with a mean reduction in tumor size of 35% +/- 14 (SD), and were treated with LITT. Each patient underwent two to seven TACE treatments (mean, 4.3) prior to LITT. In 47 patients, no reduction in tumor size was achieved, which led to further follow-up. In 33 patients, disease progression was found, with either an increasing size of the lesions (n = 18) or newly developing metastases (n = 15), and these results led to further TACE treatments or change to systemic chemotherapy. Median survival of patients who responded to this combined treatment was 26.2 months; in patients treated with only TACE, median survival was 12.8 months (range, 0.3-29.4 months). CONCLUSION: With repeated TACE, reduction in size of primary unresectable hepatic metastases is achieved in 50.6% of cases and allows local ablative treatments such as MR imaging-guided LITT.

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PURPOSE: To investigate the accuracy of different computed tomographic (CT) reformation techniques in assessing the coronary arteries. MATERIALS AND METHODS: Sixty-four patients undergoing both multi-detector row CT and invasive coronary angiography were consecutively included in a retrospective study. CT scans were obtained with collimation of 4 x 1 mm, pitch of 1.5, and rotation time of 500 msec. Retrospective electrocardiographic gating was used for image reconstruction, with 1.25-mm section thickness and 0.5-mm increment. The CT data set of each patient was evaluated by independent observers using transverse scanning, virtual endoscopic, and three-dimensional reformation and multiplanar reformation. RESULTS: Hemodynamically relevant stenoses (>50%) were detected with highest sensitivity at transverse scanning (58 of 79 [73.4%] stenoses), followed by virtual endoscopic (38 of 79 [48.1%] stenoses) and three-dimensional reformation (34 of 79 [43.0%] stenoses), and multiplanar reformation (37 of 79 [46.8%] stenoses). Atherosclerotic plaques were identified with comparable sensitivities at transverse scanning (143 of 218 plaques [65.6%]) and at three-dimensional (139 of 218 [63.8%] plaques) and virtual endoscopic reformation (136 of 218 [62.4%] plaques). Multiplanar reformation had distinctly poorer results (217 of 218 [58.3%] plaques). Combined interpretation with all four techniques increased sensitivity to 74.7% (59 of 79) for stenosis and 71.6% (156 of 218) for atherosclerosis. Calculated overall specificity was 91.4% or greater. Sufficient vascular evaluation was possible only in vessels larger than 1.6 mm in diameter. Thus, even in patients with heart rates below 60 bpm, only 80.0% of all coronary segments could be visualized, while at higher frequencies, visibility decreased to 66.2%. CONCLUSION: Although multi-detector row CT is a favorable alternative procedure in evaluating coronary arteries, its clinical value still is restricted to low heart rates and proximal coronary arterial segments.

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We report a case of a 52-year-old woman with a palpable recurrent metastasis of a neuroendocrine carcinoma to the upper outer quadrant of the right breast. For the treatment of this lesion, MR-guided laser-induced thermotherapy was performed with a cooled power laser system (Nd:YAG-Laser). An open 0.2-T MR unit was used for the monitoring of the laser energy delivery to the breast; thus, a thermosensitive fast low-angle shot 2D sequence for MR thermometry was used, so the ablation of the tumor and the increase of laser-induced necrosis could be interactively visualized with the repetitive use of this sequence. The postinterventional MR control exams 1 day and 4 months after laser-induced thermotherapy at the 1.5-T MR unit (Magnetom Symphony Quantum, Siemens, Erlangen, Germany) verified the complete ablation of the tumor without any signs of residual or relapsing tumor.

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