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V. Sawlani N. Davies M. Patel R. Flintham C. Fong G. Heyes G. Cruickshank N. Steven A. Peet A. Hartley H. Benghiat S. Meade P. Sanghera 《Clinical oncology (Royal College of Radiologists (Great Britain))》2019,31(1):41-49
Aims
Following stereotactic radiosurgery (SRS), brain metastases initially increase in size in up to a third of cases, suggesting treatment failure. Current imaging using structural magnetic resonance imaging (MRI) cannot differentiate between tumour recurrence and SRS-induced changes, creating difficulties with patient management. Combining multiparametric MRI techniques, which assess tissue physiological and metabolic information, has shown promise in answering this clinical question.Materials and methods
Multiparametric MRI techniques, including spectroscopy, diffusion and perfusion imaging, were used for the differentiation of radiation-related changes and tumour recurrence after SRS for intracranial metastases in six cases. All patients presented with enlargement of the treated lesion, an increase in perilesional brain oedema and aggravation or appearance of neurological signs and symptoms from 7 to 29 weeks after primary treatment.Results
Multiparametric imaging helped to differentiate features of tumour progression (n = 4) from radiation-related changes (n = 2). A low apparent diffusion coefficient (ADC) <1000 × 10?6 mm2/s, high relative cerebral blood volume (rCBV) ratio > 2.1, high choline:creatine (Cho:Cr) ratio > 1.8 suggested tumour recurrence. A high ADC > 1000 × 10?6 mm2/s, low rCBV ratio < 2.1, Cho:Cr ratio < 1.8 suggested SRS-induced radiation changes. Multiparametric MRI diagnosis was confirmed by histology or radiological and clinical follow-up.Conclusion
Multiparametric MRI was helpful in the early identification of radiation-related changes and tumour recurrence and may be useful for monitoring treatment changes in intracranial neoplasms after SRS treatment. 相似文献113.
Jing Qi Yuman Fong Leonard Saltz Michael I. D'Angelica Nancy E. Kemeny Mithat Gonen Jinru Shia Amita Shukla‐Dave William M. Jarnagin Richard K. G. Do Lawrence H. Schwartz Jason A. Koutcher Kristen L. Zakian 《NMR in biomedicine》2013,26(2):204-212
Hepatic steatosis is a hallmark of chemotherapy‐induced liver injury. We made serial 1H MRS measurements of hepatic lipids in patients over the time course of a 24‐week chemotherapeutic regimen to determine whether 1H MRS could be used to monitor the progression of chemotherapy‐induced steatosis. Thirty‐four patients with stage III or IV colorectal cancer receiving 5‐fluorouracil, folinic acid and oxaliplatin (n = 21) or hepatic arterial infusion of floxuridine with systemic irinotecan (n = 13) were studied prospectively. 1H MRS studies were performed at baseline and after 6 and 24 weeks of treatment. A 1H MR spectrum was acquired from the liver during a breath hold and the ratio of fat to fat + water (FFW) was calculated to give a measure of hepatic triglycerides (HTGCs). The methodology was histologically validated in 18 patients and the reproducibility was assessed in 16 normal volunteers. Twenty‐seven patients completed baseline, 6‐week and 24‐week 1H MRS examinations and one was censored. Thirteen of 26 patients (50%) showed an increase in FFW after completion of treatment. Six patients (23%) developed hepatic steatosis and two patients converted from steatosis to nonsteatotic liver. Patients whose 6‐week hepatic lipid levels had increased significantly relative to baseline also had a high probability of lipid elevation relative to baseline at the completion of treatment. Serial 1H MRS is effective for the monitoring of HTGC changes during chemotherapy and for the detection of chemotherapy‐associated steatosis. Six of 26 patients developed steatosis during chemotherapy. Lipid changes were observable at 6 weeks. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Liver stiffness measurement predicts high‐grade post‐hepatectomy liver failure: A prospective cohort study 下载免费PDF全文
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Takuya Takeichi Arti Nanda Lu Liu Amr Salam Patrick Campbell Kenneth Fong Masashi Akiyama Linda Ozoemena Kristina L. Stone Hejab Al‐Ajmi Michael A. Simpson John A. McGrath 《Experimental dermatology》2013,22(12):825-831
Individuals with inherited skin diseases often pose one of the most difficult diagnostic challenges in dermatology. The hunt for the underlying molecular pathology may involve candidate gene screening or linkage analysis, which is usually determined by the initial history, the physical findings and laboratory tests. Recent technical advances in DNA sequencing, however, are shifting the diagnostic paradigm. Notably, next‐generation sequencing allows a more comprehensive approach to diagnosing inherited diseases, with potential savings of both time and money. In the setting of a paediatric dermatology genetics clinic in Kuwait, we therefore performed whole‐exome sequencing on seven individuals without a priori detailed knowledge of the patients’ disorders: from these sequencing data, we diagnosed X‐linked hypohidrotic ectodermal dysplasia (two cases), acrodermatitis enteropathica, recessive erythropoietic protoporphyria (two siblings) and localized recessive dystrophic epidermolysis bullosa (two siblings). All these groups of disorders are clinically and genetically heterogeneous, but the sequencing data proved inherently useful in improving patient care and avoiding unnecessary investigations. Our observations highlight the value of whole‐exome sequencing, in combination with robust bioinformatics analysis, in determining the precise molecular pathology and clinical diagnosis in patients with genetic skin disorders, notably at an early stage in the clinical evaluation of these often complex disorders and thereby support a new paradigm for future diagnostics. 相似文献
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A wealth of genomic and epigenomic data has identified abnormal regulation of epigenetic processes as a prominent theme in hematologic malignancies. Recurrent somatic alterations in myeloid malignancies of key proteins involved in DNA methylation, post-translational histone modification and chromatin remodeling have highlighted the importance of epigenetic regulation of gene expression in the initiation and maintenance of various malignancies. The rational use of targeted epigenetic therapies requires a thorough understanding of the underlying mechanisms of malignant transformation driven by aberrant epigenetic regulators. In this review we provide an overview of the major protagonists in epigenetic regulation, their aberrant role in myeloid malignancies, prognostic significance and potential for therapeutic targeting. 相似文献
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Iman Parhami Timothy W. Fong Aaron Siani Claudia Carlotti Homayoon Khanlou 《AIDS and behavior》2013,17(8):2792-2801
This retrospective cohort study examined electronic medical records of HIV-positive patients in California (N = 7,834) to find the prevalence of any psychiatric condition and the associations between several factors and the likelihood of these disorders. Approximately 53 % of the patients in this study had a documented psychiatric condition, including 23 % who had a mood disorder, 19 % who had a substance-related disorder, and 16 % who had an anxiety disorder. After controlling for potential confounders, significant positive associations (p < 0.001) were found between female gender and the presence of any mood disorder (adjusted odds ratio [95 % confidence interval, 95 %CI] = 1.58 [1.26–1.99]) or anxiety disorder (AOR = 1.54 [1.18–2.02]) and between homosexual orientation and the presence of any psychiatric condition (AOR = 1.33 [1.15–1.55]), mood disorder (AOR = 1.71 [1.42–2.07]), or anxiety disorder (AOR = 1.41 [1.22–1.88]). There were also significant negative associations between African-American race and the presence of any psychiatric condition (AOR = 0.68 [0.60–0.77]), mood disorder (AOR = 0.74 [0.64–0.86]), anxiety disorder (AOR = 0.43 [0.36–0.52]), or substance-related disorder (AOR = 0.78 [0.67–0.91]) and between state/federal insurance and the presence of any psychiatric condition (AOR = 0.70 [0.62–0.79]), mood disorder (AOR = 0.71 [0.62–0.80]), or anxiety disorder (AOR = 0.77 [0.66–0.89]). 相似文献