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41.
Accurate quantification of in vivo short-echo-time (TE) (1)H spectra must account for contributions from both mobile metabolites and less mobile macromolecules, which can fluctuate in disease. The purpose of this study was to develop an approach for the acquisition and processing of macromolecule information to optimize metabolite quantification accuracy and precision. Human parietal white matter (8-cm(3) voxel) and posterior hippocampus (1.7-cm(3) voxel) metabolite levels were quantified, following manomolecule subtraction, from short-echo-time spectra (TE = 46 ms) acquired at 4.0 Tesla with localization by adiabatic selective refocusing (LASER). Nineteen metabolites were fit using a time domain Levenberg-Marquardt minimization that incorporated prior knowledge of metabolite lineshapes. The macromolecule contribution to the spectrum was reduced by 87% (P < 0.05) when the acquisition of single averages of the full spectrum and macromolecule spectrum were interleaved to reduce subtraction errors due to motion. Subtracting the Hankel Lanczos singular value decomposition (HLSVD) fit of the macromolecule spectrum, which contained no random noise, did not alter quantified metabolite levels but did not increase metabolite quantification precision. Several metabolites had higher concentrations in the posterior hippocampus compared to parietal white matter, which emphasizes the need to carefully control for partial volume contamination in hippocampal spectroscopy studies. 相似文献
42.
Ultrasonography in the diagnosis and management of 52 patients with amebic liver abscess in Cairo 总被引:1,自引:0,他引:1
L Ahmed A el Rooby M I Kassem Z A Salama G T Strickland 《Reviews of infectious diseases》1990,12(2):330-337
Clinical characteristics of 52 patients with amebic liver abscess are reported. Forty-two percent had an acute illness, usually with high fever, vomiting, sweating, pain in the abdominal right upper quadrant, and leukocytosis. The other 58% had a more chronic illness, usually with a dull ache in the right upper abdomen, weight loss, fatigue, moderate or low-grade pyrexia, and anemia. Hepatomegaly and hepatic tenderness were present in all patients; fever occurred in 75%. The diagnosis was strongly suggested by amebic antibodies in high titer and hepatic abscesses demonstrated by sonography. Mean abscess diameter was 9.2 cm; 37% were larger than 10 cm. Most abscesses were solitary (81%), in the right lobe (73%), rounded or oval (78%), cystic (57%), and had a well-defined wall (53%). However, 43% were initially solid or heterogeneous. The latter lesions always developed a cystic pattern when ultrasonography was repeated. The diagnosis was confirmed by a good clinical response to metronidazole in 50 patients. Complications included right-sided pleural effusions or empyema (13%), ascites (13%), and jaundice (13%). Drainage of large abscesses was performed in four patients. All 52 patients survived and were cured. 相似文献
43.
Lymphangiomas in children: MR imaging 总被引:9,自引:0,他引:9
Seventeen lymphangiomas in 15 patients were imaged with magnetic resonance (MR) to define the nature, extent, and anatomic relationships of these lesions. The MR and pathologic findings were then compared to determine the histologic basis for the signal-intensity characteristics of these lesions. The signal intensity of 13 lesions was similar to or slightly less than that of muscle on T1-weighted images and greater than that of fat on T2-weighted images. This appearance correlated with the presence of ectatic lymphatic channels containing clear fluid on histologic section. Four lymphangiomas had high signal intensity, approximately equal to that of fat, on T1-weighted images, reflecting the presence of clotted blood or small cystic spaces with a higher ratio of fat to fluid. Sixteen of 17 lesions had visible septations on MR images. The authors' experience suggests that most lymphangiomas have a characteristic appearance on MR images. The information obtained with MR imaging can help in providing a preoperative diagnosis, in planning surgical resection, and in defining recurrence. 相似文献
44.
Noha H. Ibrahim Mona S. Abdellateif Samar Hassab‐Allah Kassem Mohamed Ahmed Abd El Salam Mosaad M. El Gammal 《Andrologia》2019,51(10)
Prostate cancer (PC) is considered as the fifth cause of cancer deaths worldwide. The exact etiopathogenesis is unclear; however, genetic predisposition, hormonal influencers, lifestyle and environmental factors act as major contributors. It has been found that several miRNAs may play a crucial role in cancer initiation and progression. Here, in this study, we evaluated the peripheral blood levels of miR‐21, miR‐141, miR‐221 and miR‐18a expression among 80 prostate cancer patients (50 localised and 30 metastatic) and 30 benign prostatic hyperplasia patients compared to 50 normal control subjects, using RT‐PCR. Our results of analysis of miR‐21, miR‐141, miR‐18a and miR‐221 in the plasma of PC patients showed that miR‐18a is a powerful discriminator of PC patients from healthy controls as it had the highest AUC (0.966; 95% CI, 0.937–1.000), while miR‐221 provided better differentiation of metastatic from localised PC (sensitivity was 92.9% at 100% specificity), and when we combine miR‐18a and miR‐221 for differentiating patients with MPC, it will increase the sensitivity to 96.4% at a specificity of 100% (AUC, 0.997; 95% CI, 0.988–1.0) (p < .000). This current study recommends that analysis of these miRNAs might have clinical value in enhancing PSA testing. 相似文献
45.
Compared with other breast cancer subtypes, patients with triple‐negative breast cancer (TNBC), and irrespective to their disease stage, were always recognized to have the worst overall survival data. Although this does not seem different at the present time, yet the last few years have witnessed many breakthrough genomic and molecular findings, that could dramatically improve our understanding of the biological complexity of TNBC. Based on genomic analyses, it was consistently evident that TNBC comprises a heterogeneous group of cancers, which have numerous diverse molecular aberrations. This—in return—has provided a platform for a new generation of clinical trials using many innovative therapies, directed against such novel targets. At the present time, two PARP inhibitors and one anti‐PD‐L1 monoclonal antibody (in combination with chemotherapy) have been approved in certain subpopulations of metastatic TNBC (mTNBC) patients, which have finally brought this disease into the era of personalized medicine. In the current review, we will explore the genomic landscape of TNBC, through which many actionable targets were graduated. We will also discuss the results of the key—practice changing—clinical studies, and some upcoming personalized treatment options for patients with mTNBC, that may be clinically adopted in the near future. 相似文献
46.
Rania El Fekih James Hurley Vasisht Tadigotla Areej Alghamdi Anand Srivastava Christine Coticchia John Choi Hazim Allos Karim Yatim Juliano Alhaddad Siawosh Eskandari Philip Chu Albana B. Mihali Isadora T. Lape Mauricio P. Lima Filho Bruno T. Aoyama Anil Chandraker Kassem Safa James F. Markmann Leonardo V. Riella Richard N. Formica Johan Skog Jamil R. Azzi 《Journal of the American Society of Nephrology : JASN》2021,32(4):994
BackgroundDeveloping a noninvasive clinical test to accurately diagnose kidney allograft rejection is critical to improve allograft outcomes. Urinary exosomes, tiny vesicles released into the urine that carry parent cells’ proteins and nucleic acids, reflect the biologic function of the parent cells within the kidney, including immune cells. Their stability in urine makes them a potentially powerful tool for liquid biopsy and a noninvasive diagnostic biomarker for kidney-transplant rejection.MethodsUsing 192 of 220 urine samples with matched biopsy samples from 175 patients who underwent a clinically indicated kidney-transplant biopsy, we isolated urinary exosomal mRNAs and developed rejection signatures on the basis of differential gene expression. We used crossvalidation to assess the performance of the signatures on multiple data subsets.ResultsAn exosomal mRNA signature discriminated between biopsy samples from patients with all-cause rejection and those with no rejection, yielding an area under the curve (AUC) of 0.93 (95% CI, 0.87 to 0.98), which is significantly better than the current standard of care (increase in eGFR AUC of 0.57; 95% CI, 0.49 to 0.65). The exosome-based signature’s negative predictive value was 93.3% and its positive predictive value was 86.2%. Using the same approach, we identified an additional gene signature that discriminated patients with T cell–mediated rejection from those with antibody-mediated rejection (with an AUC of 0.87; 95% CI, 0.76 to 0.97). This signature’s negative predictive value was 90.6% and its positive predictive value was 77.8%.ConclusionsOur findings show that mRNA signatures derived from urinary exosomes represent a powerful and noninvasive tool to screen for kidney allograft rejection. This finding has the potential to assist clinicians in therapeutic decision making. 相似文献
47.
Tamer W. Kassem 《The Egyptian Journal of Radiology and Nuclear Medicine》2017,48(2):537-545
Objective
The aim of this study was to compare the diagnostic performance of positron emission tomography/computed tomography (PET/CT) scan and CT scan in follow up of proven gynecological malignancies omental deposits in first setting follow up after treatment.Patients and methods
60 female patients having proven omental deposits from gynecological malignancies underwent PET/CT examination following a preset protocol as baseline study. 34 cases of them had a second PET/CT examination following same protocol after 5–11 months considered as first setting follow up study aiming to assess therapeutic response.Results
Out of 34 cases 2 cases (6%) showed only newly developed lesions, 8 cases (23.5%) showed progression, 8 cases (23.5%) showed mixed response and 16 cases (47%) showed regression or complete resolution. In first setting follow up examination 18F-FDG PET/CT showed 31 TP, 2 TN and 1 FN cases while CT showed 29 TP, 2 TN, 2 FN and 1 FP cases. 18F-FDG PET/CT vs. CT revealed sensitivity, specificity and accuracy of 96.88% vs. 93.55%, 100% vs. 66.67% and 97.06% vs. 91.18% respectively.Conclusion
18F-FDG PET/CT is more accurate than CT in assessment of therapeutic response of proven gynecological malignancies omental deposits in first setting follow up. 相似文献48.
49.
Potash JB Toolan J Steele J Miller EB Pearl J Zandi PP Schulze TG Kassem L Simpson SG Lopez V;NIMH Genetics Initiative Bipolar Disorder Consortium MacKinnon DF McMahon FJ 《The American journal of psychiatry》2007,164(8):1229-1237
OBJECTIVE: The purpose of this study was to assemble and validate a database of phenotypic variables that were collected from families with bipolar disorder as a resource for genetic and other biological studies. METHOD: Participants were ascertained for two bipolar disorder genetic linkage studies: the University of Chicago, Johns Hopkins, and National Institute of Mental Health (NIMH) Intramural Program (CHIP) Collaboration and the NIMH Genetics Initiative project. All participants underwent detailed, phenotypic assessment with either the Schedule for Affective Disorders and Schizophrenia-Lifetime Version or one of four versions of the Diagnostic Interview for Genetic Studies. Clinicians reviewed the interview items and derived variable definitions that were used to extract data from the original datasets. The combined data were subjected to range and logic assessments, and a subset was re-verified against the original data. Inconsistent data and variables that were deemed unreliable were excluded. Several of the resulting variables were characterized in the total cohort and tested for familial clustering, heritability, and statistical power in genetic linkage and association studies. RESULTS: The combined database of phenotypic variables contained 197 variables on 5,721 subjects in 1,177 families. Deoxyribonucleic acid (DNA) samples are available for 5,373 of these subjects. The clinical presentation of bipolar disorder varied markedly. Most subjects suffered from serious and often disabling illness. Many phenotypic variables are strongly familial, and some quantitative variables are highly heritable. The cohort assembled in this study offers substantial power to carry out genetic linkage and association studies that use specific clinical features as covariates or as primary phenotypes. CONCLUSIONS: This is the largest database of phenotypic variables yet assembled for bipolar disorder, and it is now available to the research community. Researchers and clinicians can use this database to explore the connections between phenomenology and genetics in a cohort that is adequately powered to detect even modest genetic effects in bipolar disorder. 相似文献
50.