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Andrea Maier

Publications and source records attributed to Andrea Maier.

7 recordsLinked to original sources
PubMed2025

AUTS2-related syndrome: Insights from a large European cohort.

PURPOSE: AUTS2-related syndrome is characterized by developmental delay, autism spectrum disorder, and intellectual disability. From alternative promoters, AUTS2 encodes 2 distinct long and short isoforms encoding a putative transcriptional activator. METHODS: Through a European collaborative study, we collected clinical and genotype data on the largest AUTS2-related syndrome cohort of 58 patients harboring genomic rearrangements or single-nucleotide variants (SNVs). RESULTS: Pathogenic SNVs were recurrently found in individuals from different countries, suggesting mutational hotspots. Independent of the underlying defect at the AUTS2 locus, we observed that autistic behavior, hyperactivity, learning difficulties, and speech delay are common features of AUTS2-related syndrome. Among patients with SNVs, individuals carrying pathogenic variants affecting both longer and shorter AUTS2 transcripts showed a recognizable phenotype with microcephaly, brachycephaly, microretrognathia, broad nasal base, and anteverted nares. Behavioral disorders were more common in patients with variants affecting only the longer isoform. Arthrogryposis and stiff movements were only observed in patients with SNVs. CONCLUSION: This study provides a comprehensive clinical characterization of AUTS2-related syndrome, reveals few genotype-phenotype correlations, and suggests that the disruption of the 2 distinct AUTS2 transcripts has a different impact on the clinical phenotype.

Humans↗
PubMed2007

CT colonography: techniques, indications, findings.

Computed tomographic colonography (CTC) is a minimally invasive technique for imaging the entire colon. Based on a helical thin-section CT of the cleansed and air-distended colon, two-dimensional and three-dimensional projections are used for image interpretation. Several clinical improvements in patient preparation, technical advances in CT, and new developments in evaluation software have allowed CTC to develop into a powerful diagnostic tool. It is already well established as a reliable diagnostic tool in symptomatic patients. Many experts currently consider CTC a comparable alternative to conventional colonoscopy, although there is still debate about its sensitivity for the detection of colonic polyps in a screening population. This article summarizes the main indications, the current techniques in patient preparation, data acquisition and data analysis as well as imaging features for common benign and malignant colorectal lesions.

Colonic Polyps↗
PubMed2005

Detectability of small and flat polyps in MDCT colonography using 2D and 3D imaging tools: results from a phantom study.

OBJECTIVE: The objective of this phantom study was to determine the performance of MDCT colonography for the detection of small polyps under ideal imaging conditions and to determine the added value of 3D imaging when used as an adjunct to 2D imaging. MATERIALS AND METHODS: Thirty-six polypoid and 39 flat polyps (44 lesions, 2-5 mm; 31 lesions, 6-8 mm) were placed in three explanted segments of a thoroughly cleaned porcine colon (overall length, 4.5 m) that was distended with air and submerged in a water phantom. MDCT data sets with 4 x 1 mm collimation and 6-mm table feed were reconstructed every 0.7 mm with 1.25-mm effective slice width. The data were reviewed by three radiologists using 2D images in all three projections and with 3D volume-rendered images available as an adjunct to the 2D images. RESULTS: Additional 3D as a problem-solving tool significantly increased the overall sensitivity (96% vs 90%), decreased the total number of false-positive calls (n = 9 vs n = 5), and increased the diagnostic confidence level (p < 0.03) compared with 2D images alone. Small polyps less than or equal to 5 mm (89% vs 95%, p = 0.004) and flat polyps (82% vs 94%, p = 0.001) especially benefited from 3D. Sensitivity was generally higher for polypoid than for flat polyps (99% vs 94%, p = 0.041). CONCLUSION: Under phantom conditions, simulating an ideal clinical setup, MDCT colonography is not limited by spatial resolution and detects polyps less than or equal to 5 mm in size with high sensitivity and specificity. Additional 3D image tools improve diagnostic accuracy and reviewer confidence, especially for the detection of flat and small polyps.

Animals↗
PubMed2003

Coloproctology.

Explore the source record for details and available documents.

Colorectal Neoplasms↗
PubMed2003

Preoperative staging of rectal cancer.

Rectal cancer is one of the most frequent neoplasias, with an incidence of 40 in 100,000. For the effective use of new, differentiated treatment options, exact preoperative tumour staging is essential. The tumour stage determines whether radiation or chemotherapy should be used in addition to surgery. Endosonography allows exact differentiation of the rectal wall layers and thus of tumour stages 1-3 with median accuracy of 89%. Magnetic resonance imaging (MRI) can be employed in high and stenosing tumours and leads to an average accuracy of 85%. In recent studies, it has been shown that MRI is a valuable tool to identify the mesorectal fascia. This is a very important feature concerning the resectability and the risk of recurrence. Both, Endosonograpy and MRI plays an important and complimentary role in staging rectal cancer.

Endosonography↗
PubMed2002

Tumor necrosis factor alpha-mediated joint destruction is inhibited by targeting osteoclasts with osteoprotegerin.

OBJECTIVE: To study the effects of osteoclast-targeted therapies, such as osteoprotegerin (OPG) and pamidronate, on joint inflammation and bone destruction using a tumor necrosis factor alpha (TNF alpha)-transgenic mouse model. METHODS: Mice were placed into 5 groups that received either OPG, pamidronate, a combination of both agents, infliximab as a positive control, or phosphate buffered saline as a negative control. Treatment was initiated at the onset of arthritis, continued over 6 weeks, and thereafter, the clinical, radiologic, and histologic outcomes were assessed. RESULTS: A significant improvement in clinical symptoms, as assessed by the reduction of paw swelling, was only found in the infliximab group, whereas all other treatment groups failed to show significant improvement. However, when assessing structural damage with radiographic analysis, a significant retardation of joint damage was evident in animals treated with OPG (55% reduction of erosions), pamidronate (50% reduction of erosions) the combination therapy of OPG and pamidronate (64% reduction of erosions), and with infliximab (66% reduction of erosions). Confirming these data, quantitative histologic analysis revealed a significant reduction in the size of bone erosions in all treatment groups (OPG 56%, pamidronate 53%, OPG and pamidronate 81%, and infliximab 46%) compared with the control group. Furthermore, a significant reduction of osteoclast numbers was seen in animals treated with OPG alone or in combination with pamidronate as well as in animals treated with infliximab. CONCLUSION: These data suggest that OPG alone or in combination with bisphosphonates is an effective therapeutic tool for the prevention of TNF alpha-mediated destruction of bone by reducing the number of bone-resorbing cells in the inflammatory tissue.

Animals↗