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Caterina Marchiò Marjan Iravani Rachael Natrajan Maryou BK Lambros Felipe C Geyer Kay Savage Suzanne Parry Narinder Tamber Kerry Fenwick Alan Mackay Fernando C Schmitt Gianni Bussolati Ian Ellis Alan Ashworth Anna Sapino Jorge S Reis‐Filho 《The Journal of pathology》2009,218(3):301-315
Micropapillary carcinomas (MPCs) can present as a rare histological special type of breast cancer; however, this histological type is more frequently found admixed with invasive ductal carcinomas of no special type (IDC‐NSTs). We have previously demonstrated that pure MPCs constitute a distinct entity at the morphological and genetic levels. Here, we sought to determine whether mixed MPCs have genomic aberrations similar to those found in pure MPCs, and to investigate whether the distinct morphological components of MPCs harbour different genetic aberrations. Using high‐resolution microarray comparative genomic hybridization (aCGH), we profiled a series of 10 MPCs of mixed histology and 20 IDC‐NSTs matched for grade and oestrogen receptor (ER) status. In addition, we generated tissue microarrays containing a series of 24 pure and 40 mixed MPCs and performed immunohistochemical analysis with ER, progesterone receptor (PR), Ki‐67, HER2, cytokeratin (CK) 5/6, CK14, CK17, EGFR, topoisomerase‐IIα, cyclin D1, caveolin‐1 and E‐cadherin antibodies. In situ hybridization was employed to evaluate the prevalence of HER2, TOP2A, EGFR, CCND1, MYC and FGFR1 gene amplification. Our results demonstrate that mixed MPCs harbour similar patterns of genomic aberrations and phenotype (82.5% luminal and 17.5% HER2) compared to pure MPCs. A comparison between the distinct morphological components of mixed MPCs in a pairwise fashion revealed that both components harbour strikingly similar genomic profiles. When compared to grade‐ and ER‐matched IDC‐NSTs, mixed MPCs significantly more frequently harboured amplification of multiple regions on 8q (adjusted Fisher's p value < 0.05). Furthermore, mixed MPCs displayed higher proliferative rates than grade‐ and ER‐matched IDC‐NSTs. Our results suggest that micropapillary differentiation in breast cancer may identify a subgroup of more aggressive ER‐positive breast carcinomas, even in those featuring a mixed histology, and that mixed MPCs are more closely related to pure MPCs than to IDC‐NSTs. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
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Pushplata Prasad Arun K Tiwari KM Prasanna Kumar AC Ammini Arvind Gupta Rajeev Gupta BK Thelma 《BMC medical genetics》2010,11(1):52
Background
To determine association of nine single nucleotide polymorphisms (SNPs) in ADP ribosyltransferase-1 (ADPRT1), aldo-keto reductase family 1 member B1 (AKR1B1), receptor for advanced glycation end-products (RAGE), glutamine:fructose-6-phosphate amidotransferase-2 (GFPT2), and plasminogen activator inhibitor-1 (PAI-1) genes with chronic renal insufficiency (CRI) among Asian Indians with type 2 diabetes; and to identify epistatic interactionss between genes from the present study and those from renin-angiotensin-aldosterone system (RAAS), and chemokine-cytokine, dopaminergic and oxidative stress pathways (previously investigated using the same sample set). 相似文献75.
Sampling strategies to measure the prevalence of common recurrent infections in longitudinal studies
Wolf-Peter Schmidt Bernd Genser Mauricio L Barreto Thomas Clasen Stephen P Luby Sandy Cairncross Zaid Chalabi 《Emerging themes in epidemiology》2010,7(1):5
Background
Measuring recurrent infections such as diarrhoea or respiratory infections in epidemiological studies is a methodological challenge. Problems in measuring the incidence of recurrent infections include the episode definition, recall error, and the logistics of close follow up. Longitudinal prevalence (LP), the proportion-of-time-ill estimated by repeated prevalence measurements, is an alternative measure to incidence of recurrent infections. In contrast to incidence which usually requires continuous sampling, LP can be measured at intervals. This study explored how many more participants are needed for infrequent sampling to achieve the same study power as frequent sampling. 相似文献76.
S Kanungo BK Sah AL Lopez JS Sung AM Paisley D Sur JD Clemens G Balakrish Nair 《Bulletin of the World Health Organization》2010,88(3):185-191
Objective
To more accurately define the annual incidence of cholera in India, believed to be higher than reported to the World Health Organization (WHO).Methods
We searched the biomedical literature to extract data on the cases of cholera reported in India from 1997 to 2006 and compared the numbers found to those reported annually to WHO over the same period. The latter were obtained from WHO’s annual summaries of reported cholera cases and National health profile 2006, published by India’s Central Bureau of Health Intelligence.Findings
Of India’s 35 states or union territories, 21 reported cholera cases during at least one year between 1997 and 2006. The state of West Bengal reported cases during all 10 years, while the state of Maharashtra and the union territory of Delhi reported cases during nine, and Orissa during seven. There were 68 outbreaks in 18 states, and 222 038 cases were detected overall. This figure is about six times higher than the number reported to WHO (37 783) over the same period. The states of Orissa, West Bengal, Andaman and Nicobar Islands, Assam and Chhattisgarh accounted for 91% of all outbreak-related cases.Conclusion
The reporting of cholera cases in India is incomplete and the methods used to keep statistics on cholera incidence are inadequate. Although the data are sparse and heterogeneous, cholera notification in India is highly deficient. 相似文献77.
背景:多瘤病毒感染是导致多瘤病毒相关性肾病和移植肾失功的重要原因之一。
目的:观察分析多瘤病毒相关性肾病的临床特征及其病理学特点。
方法:121例患者移植肾活检行多瘤病毒大T抗原染色,发现9例阳性诊断为多瘤病毒相关性肾病,利用SV-40 大 T 抗原免疫组织化学染色,对确认为多瘤病毒相关性肾病患者进行临床、病理、免疫荧光、免疫组织化学观察。
结果与结论:多瘤病毒相关性肾病组肾活检时检测霉酚酸-AUC 0-12和他克莫司血药浓度均明显高于同期非多瘤病毒相关性肾病组(P < 0.05)。9例活检组织经SV-40 大T抗原染色,肾皮质和髓质均可见散在的肾小管多瘤病毒阳性。免疫荧光IgG,IgM,IgA,C3,C4,C1q和C4d全阴性,所有肾组织病理均可见肾间质大量聚集的CD3,CD4,CD8,CD68阳性细胞,1例合并排斥反应者,人白细胞DR抗原和白细胞介素2受体高表达;不合并排斥者人白细胞DR抗原和白细胞介素2受体表达多小于5%。9例多瘤病毒相关性肾病患者随访均超过半年,移植肾失功1例,3例好转,2例稳定,3例恶化。结果表明,多瘤病毒相关性肾病的诊断主要依赖于移植肾活检组织病理;利用SV-40 大T 抗原免疫组织化学染色可提高多瘤病毒相关性肾病的诊断率;移植肾组织C4d、白细胞介素2受体和人白细胞DR抗原检测对多瘤病毒感染相关性肾病的鉴别诊断具有极其重要的临床价值。 相似文献
78.
PURPOSE: To evaluate the size and geometry of thermally induced coagulation by using multipolar radiofrequency (RF) ablation and to determine a mathematic model to predict coagulation volume. MATERIALS AND METHODS: Multipolar RF ablations (n = 80) were performed in ex vivo bovine livers by using three internally cooled bipolar applicators with two electrodes on the same shaft. Applicators were placed in a triangular array (spacing, 2-5 cm) and were activated in multipolar mode (power output, 75-225 W). The size and geometry of the coagulation zone, together with ablation time, were assessed. Mathematic functions were fitted, and the goodness of fit was assessed by using r(2). RESULTS: Coagulation volume, short-axis diameter, and ablation time were dependent on power output and applicator distance. The maximum zone of coagulation (volume, 324 cm(3); short-axis diameter, 8.4 cm; ablation time, 193 min) was induced with a power output of 75 W at an applicator distance of 5 cm. Coagulation volume and ablation time decreased as power output increased. Power outputs of 100-125 W at applicator distances of 2-4 cm led to a reasonable compromise between coagulation volume and ablation time. At 2 cm (100 W), coagulation volume, short-axis diameter, and ablation time were 66 cm(3), 4.5 cm, and 19 min, respectively; at 3 cm (100 W), 90 cm(3), 5.2 cm, and 22 min, respectively; at 4 cm (100 W), 132 cm(3), 6.1 cm, and 27 min, respectively; at 2 cm (125 W), 56 cm(3), 4.2 cm, and 9 min, respectively; at 3 cm (125 W), 73 cm(3), 4.9 cm, and 12 min, respectively; and at 4 cm (125 W), 103 cm(3), 5.5 cm, and 16 min, respectively. At applicator distances of 4 cm (>125 W) and 5 cm (>100 W), the zones of coagulation were not confluent. Coagulation volume (r(2) = 0.80) and RF ablation time (r(2) = 0.93) were determined by using the mathematic model. CONCLUSION: Multipolar RF ablation with three bipolar applicators may produce large volumes of confluent coagulation ex vivo. A compromise is necessary between prolonged RF ablations at lower power outputs, which produce larger volumes of coagulation, and faster RF ablations at higher power outputs, which produce smaller volumes of coagulation. 相似文献
79.
Gogtay N Nugent TF Herman DH Ordonez A Greenstein D Hayashi KM Clasen L Toga AW Giedd JN Rapoport JL Thompson PM 《Hippocampus》2006,16(8):664-672
The hippocampus, which plays an important role in memory functions and emotional responses, has distinct subregions subserving different functions. Because the volume and shape of the hippocampus are altered in many neuropsychiatric disorders, it is important to understand the trajectory of normal hippocampal development. We present the first dynamic maps to reveal the anatomical sequence of normal human hippocampal development. A novel hippocampal mapping technique was applied to a database of prospectively obtained brain magnetic resonance imaging (MRI) scans (100 scans in 31 children and adolescents), scanned every 2 yr for 6-10 yr between ages 4 and 25. Our results establish that the structural development of the human hippocampus is remarkably heterogeneous, with significant differences between posterior (increase over time) and anterior (loss over time) subregions. These distinct developmental trajectories of hippocampal subregions may parallel differences in their functional development. 相似文献
80.