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Castillo M. Neuroimaging and cartography: mapping brain tumors. AJNR Am J Neuroradiol 2001; 22:597-8. [PMID: 11290462 PMCID: PMC7976033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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277
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Castillo M, Davis PC, Takei YD, Schwartzberg DG, Hoffman JC. Intracranial cystic malignant fibrous histiocytoma in a child: sonographic and CT findings. Pediatr Radiol 2001; 20:194-5. [PMID: 2162025 DOI: 10.1007/bf02012974] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Primary intracranial cystic malignant fibrous histiocytoma (MFH) is an extremely rare tumor with only 15 cases reported. Only three cases of cystic intracranial MFH are found in the literature. We present the sonographic and CT findings in a child with such a lesion.
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Stone JA, Cooper H, Castillo M, Mukherji SK. Malignant schwannoma of the trigeminal nerve. AJNR Am J Neuroradiol 2001; 22:505-7. [PMID: 11237974 PMCID: PMC7976843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
SUMMARY We present the MR imaging, CT, and clinical findings of a patient with malignant schwannoma of the trigeminal nerve. Local tumor recurrence is frequent and may be mistaken for lymphatic spread. In this report, we emphasize the natural history of this rare tumor and discuss the importance of imaging in diagnosis and surveillance.
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Krishnan A, Patkar D, Patankar T, Shah J, Prasad S, Bunting T, Castillo M, Mukherji SK. Craniovertebral junction tuberculosis: a review of 29 cases. J Comput Assist Tomogr 2001; 25:171-6. [PMID: 11242209 DOI: 10.1097/00004728-200103000-00003] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE The purpose of this work was to describe the various imaging findings in craniovertebral tuberculosis and the importance of imaging in treatment in these patients. METHOD A retrospective review of MR and CT scans in 29 patients with craniovertebral tuberculosis was performed. The images were reviewed, paying special attention to both bony (skull base, atlas, and axis) and soft tissue involvement in addition to atlantoaxial dislocation, lateral subluxation of the dens, and compression of the spinal cord. RESULTS Suboccipital pain with neck stiffness was the most common presenting symptom in our patients. The skull was involved in 19 of the 29 cases, clivus involvement was seen in 11 patients, and occipital condyle involvement was present in 14 patients. Detailed analysis of atlas involvement due to tuberculosis showed the lateral masses to be predominantly affected. The dens was involved in 18 cases (62%). Soft tissue masses in the prevertebral area were seen in 22 patients, paravertebral in 27 patients, and epidural involvement in 25 patients was identified. Atlantoaxial displacement was present in seven cases, lateral mass-dens subluxation in five, and superior subluxation of the dens through the foramen magnum compressing the medulla was seen in two cases. Spinal cord compression with intrinsic cord changes was noted in 12 cases. All patients received multidrug antituberculous therapy for 1 year. The presence of neurologic deficit and instability of the atlantoaxial complex was pivotal in further management in these patients. CONCLUSION A high degree of clinical suspicion is necessary when confronted with patients with neck stiffness and tenderness over the upper cervical vertebrae. MRI in these patients provides a sensitive method for the diagnosis of craniovertebral tuberculosis.
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MESH Headings
- Abscess/complications
- Abscess/diagnosis
- Abscess/diagnostic imaging
- Adolescent
- Adult
- Aged
- Aged, 80 and over
- Axis, Cervical Vertebra/diagnostic imaging
- Axis, Cervical Vertebra/pathology
- Cervical Atlas/diagnostic imaging
- Cervical Atlas/pathology
- Child
- Child, Preschool
- Female
- Humans
- Infant
- Magnetic Resonance Imaging
- Male
- Middle Aged
- Neck/diagnostic imaging
- Neck/pathology
- Occipital Bone/diagnostic imaging
- Occipital Bone/pathology
- Retrospective Studies
- Spinal Cord Compression/complications
- Spinal Cord Compression/diagnosis
- Spinal Cord Compression/diagnostic imaging
- Tomography, X-Ray Computed
- Tuberculosis, Osteoarticular/complications
- Tuberculosis, Osteoarticular/diagnosis
- Tuberculosis, Osteoarticular/diagnostic imaging
- Tuberculosis, Spinal/complications
- Tuberculosis, Spinal/diagnosis
- Tuberculosis, Spinal/diagnostic imaging
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García-Cabanes C, Palmero M, Bellot JL, Castillo M, Orts A. Inhibition of COX in ocular tissues: an in vitro model to identify selective COX-2 inhibitors. J Ocul Pharmacol Ther 2001; 17:67-74. [PMID: 11322639 DOI: 10.1089/108076801750125711] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The aim of this work was to study the regulation of LPS-stimulated PGE 2 synthesis by traditional NSAIDs (piroxicam and diclofenac) and a selective COX-2 inhibitor (NS-398), in cultured bovine corneal endothelial cells and retinal pigmentary epithelial cells. The IC50 values of piroxicam and diclofenac were compared with IC50 values of NS-398, diclofenac, in both types of cells, showed higher potency than piroxicam. Diclofenac seemed to be a COX-2 inhibitor because its IC50 values were similar to the IC50 values of NS-398. We suggest that this in vitro cell assay system could be useful for identifying compounds that selectively inhibit COX-2 in ocular tissues.
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281
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Castillo M, Smith JK, Kwock L. Proton MR spectroscopy in patients with acute temporal lobe seizures. AJNR Am J Neuroradiol 2001; 22:152-7. [PMID: 11158901 PMCID: PMC7975544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
BACKGROUND AND PURPOSE Decreases in N-acetyl aspartate (NAA) as seen by proton MR spectroscopy are found in hippocampal sclerosis, and elevated levels of lipids/lactate have been observed after electroconvulsive therapy. Our purpose was to determine whether increased levels of lipids/lactate are found in patients with acute seizures of hippocampal origin. METHODS Seventeen patients with known temporal lobe epilepsy underwent proton MR spectroscopy of the mesial temporal lobes within 24 hours of their last seizure. Four of them were restudied when they were seizure-free. Five healthy individuals were used as control subjects. All MR spectroscopy studies were obtained using a single-voxel technique with TEs of 135 and 270. The relationship between the presence of lipids/lactate and seizures was tested using Fisher's exact test. Mean and standard deviations for NAA/creatine (Cr) were obtained in the hippocampi in patients with seizures on initial and follow-up studies and these values were compared with those in the control subjects. RESULTS Seizure lateralization was obtained in 15 patients. Of the 17 seizure locations that involved hippocampi, 16 showed lipids/lactate by proton MR spectroscopy. Of the 13 hippocampi not directly affected by seizures, 10 showed no lipids/lactate and three showed lipids/lactate. The relationship between lipids/lactate and seizure location was confirmed. A comparison of NAA/Cr ratios for the involved hippocampi with those in control subjects showed significant differences on initial MR spectroscopy; however, no significant difference was found between acute and follow-up NAA/Cr ratios in hippocampi affected by seizures. CONCLUSION Lipids/lactate were present in the hippocampi of patients with acute seizures and decreased when the patients were seizure-free. Thus, lipids/lactate may be a sensitive marker for acute temporal lobe seizures.
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Abstract
Cryptococcal infection is common in immunocompromised patients, often presenting with meningitis or meningoencephalitis. We report an unusual presentation of cryptococcal infection in an immunocompetent patient presenting with headache and hemiplegia. CT demonstrated a large ring-enhancing lesion in the parietal region with intralesional calcification.
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283
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Castillo M, Smith JK, Kwock L, Wilber K. Apparent diffusion coefficients in the evaluation of high-grade cerebral gliomas. AJNR Am J Neuroradiol 2001; 22:60-4. [PMID: 11158889 PMCID: PMC7975568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
BACKGROUND AND PURPOSE Preliminary data indicate that apparent diffusion coefficient (ADC) values may be useful in identifying and grading primary cerebral tumors. We tested the hypothesis that ADC values can be used to differentiate tumor, edema, and normal brain tissue. METHODS Fifteen patients with high-grade cerebral astrocytomas underwent conventional MR imaging, diffusion-weighted MR imaging, and proton MR spectroscopy. We defined tumor as an area containing the highest choline/creatine and choline/N-actetyl aspartate ratios, contrast enhancement, and abnormal T2 signal intensity. Edema was defined as tissue with normal proton MR spectra, no enhancement, and high T2 signal intensity. Normal brain was assumed if tissue had normal proton MR spectra, no enhancement, and normal T2 signal intensity in the hemispheres ipsilateral or contralateral to tumor. ADC maps were calculated and regions of interest were manually placed over areas of tumor, edema, and normal tissue. Comparisons were made by analysis of variance. For post hoc testing, the Tukey method was used to correct for the effect of multiple comparisons, and significance was accepted if P was less than .05. RESULTS When ADC values were analyzed as a group, significant differences were found between tumor (131 + 45) and normal brain tissue (ipsilateral to tumor, 92 + 22; contralateral to tumor, 78 + 5) but not between tumor and adjacent edema (129 + 45). A plot of individual data points showed considerable overlapping among the three types of tissue sampled. CONCLUSION As a group, ADC values helped to distinguish high-grade glioma from normal tissue but could not be used to separate high-grade glioma from surrounding edema. Individually, ADC values overlapped considerably and were not useful in our patients. The utility of ADC values (as obtained in this relatively small study) is questionable in patients with high-grade cerebral astrocytomas.
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Castillo M, Ayers RA, Zhang X, Schowengerdt F, Moore JJ. Combustion synthesis of porous glasses and ceramics for bone repair. BIOMEDICAL SCIENCES INSTRUMENTATION 2001; 37:469-74. [PMID: 11347436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
Porous bioactive materials with constituents such as CaO, P2O5, SiO2, MgO, K2O, Na2O implanted in bone can activate a biologic response to enhance bone healing. These biomaterials are currently formed utilizing wet chemistry, plasma spray, D-gun, sintering, and diffusion bond techniques. This work investigates the use of self propagating high temperature combustion synthesis (SHS) in the creation of porous bioactive glasses for bone repair. The use of combustion synthesis has many advantages over the methods mentioned previously. The primary advantages are the ability to control the process to provide specified porosity (% porosity, pore size distribution, interconnected pores, functionally grading of porosity), structural mechanical properties, together with rapid production of the material. The focus of this project is the investigation of combustion synthesis reactions based on the reaction system 3CaO + P2O5==>Ca3(PO4)2 and incorporating other known biocompatible constituents into the reaction.
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la Farré M, García MJ, Castillo M, Riu J, Barceló D. Identification of surfactant degradation products as toxic organic compounds present in sewage sludge. ACTA ACUST UNITED AC 2001; 3:232-7. [PMID: 11354738 DOI: 10.1039/b100945l] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A cost-effective strategy combining chemical analysis and bioassays for the identification of polar toxic compounds in sewage sludge is reported. ToxAlert 100 bioluminescence inhibition assay was used in combination with chemical analysis involving extraction, clean-up, chromatographic separation and mass spectrometry detection. This methodology was applied to real samples of sludge from three wastewater treatment plants (WWTP) located in Catalonia (Spain) during a 3 month period. In the first step, sewage sludge was lyophilized, treated by sonication with a mixture of methanol and chloroform and finally cleaned up using a sequential solid phase extraction (SSPE) with an octadecylsilica cartridge (C18) in series with a polymeric Lichrolut EN cartridge (Lic EN). In the second step, the toxicity of each fraction of the sludge sample was investigated using the ToxAlert 100. The unequivocal identification and quantification of polar organic cytotoxic substances present in the fractionated extracts were determined by liquid chromatography-mass spectrometry (LC-MS). Major toxic compounds identified were: non-ionic polyethoxylated surfactants (nonylphenol polyethoxylates, alcohol polyethoxylates), their intermediates (polyethylene glycol polyethoxylated, nonylphenol carboxylates and polyethoxylated alcohol carboxylates), linear alkylbenzenesulfonates and heavy metals. The toxic response (in terms of bioluminescence inhibition using ToxAlert 100), defined by the 50% effective concentration (EC50), and the toxicity units (TU) for every standard non-ionic surfactant were calculated. The results provided the identification of polar cytotoxic compounds as well as the evaluation of their contribution to the total toxicity observed in sewage sludge.
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286
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Castillo M, Alonso M, Riu J, Reinke M, Klöter G, Dizer H, Fischer B, Hansen P, Barceló D. Identification of cytotoxic compounds in European wastewaters during a field experiment. Anal Chim Acta 2001. [DOI: 10.1016/s0003-2670(00)00829-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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287
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Castillo M, Mukherji SK. Diffusion-weighted imaging in the evaluation of intracranial lesions. Semin Ultrasound CT MR 2000; 21:405-16. [PMID: 11138630 DOI: 10.1016/s0887-2171(00)90033-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Conventional magnetic resonance (MR) imaging is able to show pathology early on and to provide the radiologist with some degree of lesion characterization based on the relaxation time of different tissues. Many times, however, conventional MR imaging is not capable of depicting abnormalities at a time when early therapy may be successful, or of differentiating among different types of lesions before surgery. Diffusion-weighted imaging (DWI), a technique that is relatively new, is rapidly gaining popularity. Its increased use stems from the fact that many of the newer MR units are echo-planar capable. Although DWI may be obtained without echo-planar techniques, most DWI is now obtained by using gradients capable of very fast rising times. Echo-planar DWI may be obtained in a matter of seconds and, thus, is much less sensitive to bulk motion than other imaging techniques. Although DWI has been used extensively for the evaluation of acute cerebral infarctions, new uses for it are being explored constantly. In this article we address the nature of DWI and its use in the stroke patient as well as in other clinical situations where we believe it is useful.
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288
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Castillo M, Mukherji SK. Clinical applications of FLAIR, HASTE, and magnetization transfer in neuroimaging. Semin Ultrasound CT MR 2000; 21:417-27. [PMID: 11138631 DOI: 10.1016/s0887-2171(00)90034-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We review the clinical utility of three commonly used and relatively new magnetic resonance techniques as it pertains to neuroimaging. These techniques include fluid-attenuated inversion-recovery (FLAIR) images, half-Fourier acquisition single-shot turbo spin echo (HASTE) images, and magnetization transfer (MT). These techniques may be used to improve image quality and, in some cases, increase the sensitivity and the specificity of magnetic resonance imaging of the brain and spine.
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289
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Maheshwari SR, Fatterpekar GM, Castillo M, Mukherji SK. Proton MR spectroscopy of the brain. Semin Ultrasound CT MR 2000; 21:434-51. [PMID: 11138633 DOI: 10.1016/s0887-2171(00)90036-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Magnetic resonance spectroscopy (MRS) has been shown to be an effective noninvasive diagnostic tool that can be used to monitor serially biochemical and metabolic changes in serial disease processes that affect the brain. MRS is now a clinical tool that is reimbursable. This article reviews MRS physics, techniques, pulse sequences, and the clinical applications of MRS.
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Castillo M. Further explanations for the formation of syringomyelia: back to the drawing table. AJNR Am J Neuroradiol 2000; 21:1778-9. [PMID: 11110524 PMCID: PMC7974291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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291
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Castillo M, Mukherji SK, McCartney WH. Cerebral amobarbital sodium distribution during Wada testing: utility of digital subtraction angiography and single-photon emission tomography. Neuroradiology 2000; 42:814-7. [PMID: 11151686 DOI: 10.1007/s002340000438] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
We aimed to determine if the cerebral distribution of anesthetic during Wada testing is reflected by findings on digital subtraction angiography (DSA) and single-photon emission computed tomography (SPECT) and if the findings on these studies are relevant to the outcome of the Wada test. We carried out selective internal carotid artery (ICA) DSA on 29 patients underwent studies prior to a Wada test. In patients without angiographic cross-filling, amobarbital and a radiotracer were injected into each ICA, beginning with the epileptogenic side. In patients with cross-filling, the ICA ipsilateral to the epileptogenic focus was injected with amobarbital and radiotracer while other was injected with amobarbital alone. We analyzed the DSA studies for cross-filling and filling of the posterior cerebral arteries (PCA). We reviewed the SPECT for activity in the territories of the anterior, middle cerebral, and posterior cerebral arteries. We compared the results of both studies with the success or failure of the neuropsychological portion of the Wada test. In 20 patients without cross-filling, the results of DSA and SPECT were comparable: symmetrical hemisphere activity was seen. In nine patients with cross-filling, SPECT showed bilateral, almost symmetrical activity. Filling or nonfilling of the PCA correlated with activity (or lack of it) in the medial temporal and occipital regions in all patients. The Wada test was considered successful in all patients. The findings on SPECT did not alter interpretation of the Wada test and we suggest that it may not be needed in all patients undergoing Wada testing.
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292
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Solé M, Castillo M, Lopez de Alda MJ, Porte C, Barceló D. Estrogenicity determination in carp, Cyprinus carpio: a laboratory and field approach. ACTA ACUST UNITED AC 2000. [DOI: 10.1051/analusis:2000280783] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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293
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Quencer RM, Ball WS, Castillo M, Davis PC, Dillon WP, Falcone S, Strother CM, Zimmerman RD. Thirty-eighth annual meeting of the American Society of Neuroradiology. AJNR Am J Neuroradiol 2000; 21:1962-8. [PMID: 11110555 PMCID: PMC7974293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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294
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Maheshwari SR, Mukherji SK, Neelon B, Schiro S, Fatterpekar GM, Stone JA, Castillo M. The choline/creatine ratio in five benign neoplasms: comparison with squamous cell carcinoma by use of in vitro MR spectroscopy. AJNR Am J Neuroradiol 2000; 21:1930-5. [PMID: 11110549 PMCID: PMC7974295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/1999] [Accepted: 05/30/2000] [Indexed: 02/18/2023]
Abstract
BACKGROUND AND PURPOSE The choline (Cho)/creatine (Cr) ratio has been shown to be a reliable proton MR spectroscopy metabolic marker for differentiating squamous cell carcinoma (SCCA) from normal muscle in the upper aerodigestive tract. However, it is unclear whether the Cho/Cr ratio can be used to differentiate a malignant tumor from a benign neoplasm in the extracranial head and neck. Our purpose was to determine whether the Cho/Cr ratio can be used to differentiate benign from malignant tumors in this region. METHODS In vitro one-dimensional proton MR spectroscopy (2,000/136,272 [TR/TE]) was performed at 11 T on tissue specimens obtained from glomus tumors (n = 3), inverting papilloma (n = 1), and schwannoma (n = 1). Cho/Cr area ratios were calculated and compared with similar, previously reported in vitro (11 T) findings and with samples of SCCA and normal muscle. RESULTS The Cho/Cr ratio was elevated in relation to muscle in all benign tumors at TE = 136 (glomus tumors = 4.52, inverting papilloma = 3.85, schwannoma = 2.2) and at TE = 272 (glomus tumors = 8.01, inverting papilloma = 2.1, schwannoma = 4.28). The average Cho/Cr ratio for benign lesions was 3.92 (TE = 136) and 6.11 (TE = 272). The Cho/Cr ratio was significantly higher in benign tumors than in both SCCA and muscle. The average Cho/Cr ratio for muscle at TEs of 136 and 272 was 1.16 and 1.31, respectively, whereas for SCCA the average Cho/Cr ratio at TEs of 136 and 272 was 1.67 and 2.45, respectively. CONCLUSION In our small group, the Cho/Cr ratio was significantly higher in benign tumors than in muscle and SCCA of the extracranial head and neck.
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295
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Castillo M, Martínez E, Ginebreda A, Tirapu L, Barceló D. Determination of non-ionic surfactants and polar degradation products in influent and effluent water samples and sludges of sewage treatment plants by a generic solid-phase extraction protocol. Analyst 2000; 125:1733-9. [PMID: 11070540 DOI: 10.1039/b004071l] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Non-ionic polyethoxylated surfactants (nonylphenol polyethoxylates, alcohol polyethoxylates), their breakdown products (polyethylene glycol, polyethoxylated nonylphenol carboxylates and polyethoxylated alcohol carboxylates) and other compounds were identified and measured in various waste-water treatment samples (influent, effluent and sludge). A generic protocol involving the use of sequential solid-phase extraction (SSPE) with octadecylsilica and styrene-divinylbenzene cartridges in series and differential elution was used. Fractionated extracts were analyzed by liquid chromatography-mass spectrometry (LC-MS) using atmospheric pressure chemical ionization (APCI) in the positive and negative ionization modes. For sewage treatment plant (STP) sludge, the extraction protocol involved lyophilization of the sludge followed by sonication with MeOH-CH2Cl2 (7 + 3) and final clean-up using the SSPE protocol. Limits of detection for target analytes ranging from 1.1 to 4.1 micrograms L-1 for water samples and from 0.11 to 0.28 mg kg-1 for sludge were achieved. The results obtained demonstrated the inefficient removal of the target analytes in physico-chemical STPs whereas their elimination factors in STPs with biological treatment reached average values of 77, 92 and 98% for alcohol polyethoxylates, nonylphenol polyethoxylates (NPEOs) and polyethylene glycols (PEGs), respectively. Quantitative elimination of coconut fatty acid diethanolamide (CDEA) surfactants in the activated sludge process occurred. In contrast, total removal of NPEOs led to the formation of persistent and toxic metabolites such as nonylphenol which was present in treated effluent as well as in sludge samples with average concentrations ranging from 15.0 to 251.2 micrograms L-1 and from 13.5 to 74.2 mg kg-1, respectively. Polyethoxylated carboxylates and short chain NPEOs were also detected at similar levels in the effluents and sludges. In addition, a linear correlation between the total phenolic concentration (Total Ph) measured by the 4-aminoantipyrine method and the total concentration of nonylphenolic compounds (Total NP) measured by SSPE-LC-APCI-MS was observed.
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Castillo M, Smith JK, Kwock L. Correlation of myo-inositol levels and grading of cerebral astrocytomas. AJNR Am J Neuroradiol 2000; 21:1645-9. [PMID: 11039343 PMCID: PMC8174883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
BACKGROUND AND PURPOSE In a limited number of patients, the level of myo-inositol (MI), as seen by proton magnetic resonance spectroscopy (HMRS), has been shown to differ for gliomas of different histologic grades. We sought to determine if MI levels correlate with cerebral astrocytoma grade. METHODS Five control subjects, 14 patients with low-grade astrocytoma, 10 patients with anaplastic astrocytoma, and 10 patients with glioblastoma multiforme (GBM) underwent single-volume HMRS with an echo time of 20 ms. Twenty-five patients had received surgery, chemotherapy, and/or radiation therapy previously. Using the curve-fitting program supplied by the manufacturer, peak areas for n-acetyl aspartate (NAA), choline (Cho), and MI were normalized with respect to the peak area of creatine (Cr). Ratios for MI/Cr, Cho/Cr, and NAA/Cr were obtained for each lesion and retrospectively compared with the histologic grade of the lesion. RESULTS Levels of MI/Cr were higher (0.82 +/- 0.25) in patients with low-grade astrocytoma, intermediate (0.49 +/- 0.07) in control subjects, and lower in patients with anaplastic astrocytoma (0.33 +/- 0.16) and GBM (0.15 +/- 0.12). CONCLUSION Our study shows a trend toward lower MI levels in the presence of anaplastic astrocytomas and GBMs compared with those of low-grade astrocytomas. MI levels may have implications in the grading of cerebral astrocytomas.
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297
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Armao D, Castillo M, Chen H, Kwock L. Colloid cyst of the third ventricle: imaging-pathologic correlation. AJNR Am J Neuroradiol 2000; 21:1470-7. [PMID: 11003281 PMCID: PMC7974047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Colloid cysts are relatively rare intracranial lesions located in the rostral aspect of the third ventricle. They may produce acute hydrocephalus, brain herniation, and lead to death. Although the clinical and imaging features of colloid cysts are well known, their etiology and the factors responsible for their imaging features continue to be a subject of debate. We present the imaging-pathologic correlation of a patient with a colloid cyst as well as data supporting the fact that the presence of cholesterol is probably responsible for the MR imaging features exhibited by some colloid cysts.
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298
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Castillo M, Riu J, Ventura F, Boleda R, Scheding R, Schröder HF, Nistor C, Emneus J, Eichhorn P, Knepper TP, Jonkers CC, de Voogt P, González-Mazo E, León VM, Barceló D. Inter-laboratory comparison of liquid chromatographic techniques and enzyme-linked immunosorbent assay for the determination of surfactants in wastewaters. J Chromatogr A 2000; 889:195-209. [PMID: 10985551 DOI: 10.1016/s0021-9673(00)00398-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Seven laboratories participated in an inter-laboratory comparison exercise within the framework of the PRISTINE, SANDRINE and INEXsPORT European Union Projects. Solid-phase extraction (SPE) methodologies were used for the extraction of target analytes from wastewaters. The analytical strategies were based on liquid chromatography (LC) coupled to mass spectrometric (MS) or to fluorescent (FL) detection in all cases with the exception of one laboratory using a test-tube enzyme-linked immunosorbent assay kit. Samples were spiked with the surfactants nonylphenolpolyglycol ether, coconut diethanolamide, linear alkylbenzene sulfonate, nonylphenolpolyglycol ether sulfate, alkylpolyglycol ether and secondary alkane sulfonate. After enrichment on previously conditioned SPE cartridges, the SPE cartridges were distributed among the participating laboratories without the information about the amount of spiked surfactants. In addition, SPE cartridges loaded with a real-world environmental sample containing a tannery wastewater were also analyzed. The results of the programme showed that SPE followed by LC-MS techniques are reliable for the surfactants determination at submicrogram to microgram per liter levels in wastewaters. Inter-laboratory precision values were calculated as the reproducibility relative standard deviation (RSD(R)) which was determined from the reproducibility standard deviation (sR) and the average concentration at a particular concentration level. When data from all laboratories were pooled, the RSD(R) values ranged from 5.1 to 28.3% for the determination of target analytes. The most accurate result corresponded to that given for linear alkylbenzene sulfonates. Taking into account that different methodologies were used (including non-chromatographic techniques) and the complexity of the samples analyzed, it can be considered that acceptable reproducibility values were obtained in this inter-laboratory study.
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