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S Kremer

Publications and source records attributed to S Kremer.

At least 19 recordsLinked to original sources
PubMed2002

Dynamic contrast-enhanced MRI: differentiating melanoma and renal carcinoma metastases from high-grade astrocytomas and other metastases.

We performed conventional and dynamic susceptibility-contrast MRI imaging in 38 patients with brain tumours: 20 with metastases (breast carcinoma: two; renal carcinoma: five; colorectal carcinoma: one; lung carcinoma: seven; melanoma: five), and 18 with high-grade astrocytomas. We obtained cerebral blood volume (CBV) maps and calculated the relative CBV (rCBV) in different areas using the ratio between the CBV in the pathological area (CBVp) and in the contralateral white matter (CBVn). We calculated the maximum rCBV (rCBVmax) for each tumour and compared the mean rCBVmax in each group of tumours. The mean rCBV of melanoma metastases (5.35+/-2.32, range 3.14-9.23) and of renal carcinoma metastases (8.17+/-2.39, range 5.41-11.64) were significantly greater than those of high-grade astrocytomas (2.61+/-1.17, range 1.3-5.0) ( P=0.002 and <0.001, respectively) and of lung carcinoma metastases (2.94+/-0.86, range 1.43-4.04) ( P=0.003 and 0.002). There was no statistically significant difference between the mean rCBV of lung metastases and of high-grade astrocytomas ( P=0.59). Large, solitary, necrotic metastases can be indistinguishable from high-grade astrocytomas using conventional MRI. Demonstration of an elevated rCBV which may suggest a hypervascular lesion such as renal carcinoma or melanoma.

Astrocytoma↗
PubMed2002

Chordoid glioma of the third ventricle: CT and MRI, including perfusion data.

Chordoid glioma is a homogeneous tumour involving the third ventricular region of middle-aged women, containing a small central cyst or necrosis. Histologically the tumour has a chordoid appearance. We report a new case with a haemodynamic imaging approach which indicates tumour angiogenesis at the capillary level.

Adult↗
PubMed2002

Cerebral blood volume mapping by MR imaging in the initial evaluation of brain tumors.

PURPOSE: To assess the contribution of magnetic resonance (MR) cerebral blood volume (CBV) mapping in the initial evaluation of brain tumors. METHODS: 63 patients presenting a brain tumor underwent dynamic susceptibility-contrast MR imaging before surgery or biopsy: 28 high grade gliomas, 8 low grade gliomas, 2 pilocytic astrocytomas, 4 lymphomas, 12 metastases, 9 meningiomas. The CBV maps were obtained for each patient and the relative CBV (rCBV) in different areas was calculated using the ratio between the CBV in the pathological area (CBVp) and in the contralateral normal tissue(CBVn). The maximum rCBV (rCBVmax) for each tumor was determined and the mean values of rCBVmax in each group of tumors were compared using an unpaired Student t test (p=0.05). RESULTS: The rCBVmax for high grade gliomas (mean +/- SD: 2.6 +/- 1,2) was statistically different from low grade gliomas (0.9 +/- 0.4) (p<0.001), lymphomas (0.7 +/- 0.2) (p=0.002), meningiomas (9.1 +/- 4.4) (p<0.001) and kidney metastases (8.9 +/- 2.1) (p<0.001). The two pilocytic astrocytomas had a much lower rCBVmax than high grade gliomas. No statistically significant difference was found between high grade gliomas and lung metastases (2.4 +/- 0.9) (p=0.72). CONCLUSION: CBV mapping provides additional information on the vascularity of the lesions, which is not available with conventional MR imaging. It might be useful for differentiating certain lesions showing contrast enhancement, mainly high grade gliomas from kidney metastases, meningiomas, lymphomas or pilocytic astrocytomas.

Blood Volume↗
PubMed2002

[Focal cortical dysplasia possibly related to a probable prenatal ischemic injury].

Focal cortical dysplasias are a frequent etiology of partial seizure disorders refractory to medical treatment. We report the case of a patient with focal cortical dysplasia, confirmed by surgery, in association with ischemic cerebral lesions that possibly occurred during the intra-uterine development. This observation reinforces the hypothesis of a possible factor of causality between prenatal ischemia and anomalies of cortical development.

Anticonvulsants↗
PubMed2001

Human recombinant interferon-alpha2a and interferon-alphaA/D have different effects on bleomycin-induced lung injury.

BACKGROUND: Bleomycin (Bleo)-induced lung injury in mice serves as an animal model of pulmonary fibrosis. The pathogenesis of pulmonary fibrosis remains unclear, but it comprises both inflammatory and fibrotic components. The cytokine interferon (IFN)-alpha is produced by macrophages and may modulate both fibrogenesis and the determination of T lymphocyte phenotype in pulmonary fibrosis. OBJECTIVE: To investigate the effect of two preparations of recombinant IFN-alpha (IFN-alphaA/D and IFN-alpha2a) on Bleo-induced lung injury in C57BL/6 mice. METHODS: Mice were treated by a single intratracheal (IT) instillation of 0.06 mg of Bleo in 0.1 ml of saline or saline alone. One of two different IFN-alpha preparations, IFN-alphaA/D or IFN-alpha2a in saline, or saline alone were administered by daily intraperitoneal injections starting 1 day prior to IT instillation. The treatment groups were as follows: IT Bleo and intraperitoneal saline; IT Bleo and intraperitoneal IFN-alpha2a; IT Bleo and intraperitoneal IFN-alphaA/D; IT saline and intraperitoneal IFN-alphaA/D or IFN-alpha2a; IT saline and intraperitoneal saline. The animals were sacrificed 14 days after IT instillation. Lung injury was evaluated by total and differential cell count in bronchoalveolar lavage (BAL) fluid, by a semiquantitative morphological index of lung injury and a quantitative image analysis of cellularity and fibrosis fraction and by biochemical analysis of lung hydroxyproline content. RESULTS: In Bleo-treated mice, IFN-alpha2a treatment caused a significant rise in BAL lymphocytes and in cellularity and fibrosis fractions in lung tissue. In contrast, IFN-alphaA/D treatment had no effect on Bleo-induced lung injury. CONCLUSION: IFN-alpha may enhance Bleo-induced lung injury but this effect varies with different IFN preparations.

Animals↗
PubMed2000

[Neuroradiology].

Explore the source record for details and available documents.

Brain Diseases↗
PubMed2000

[NMR perfusion imaging: applications to the study of brain tumor angiogenesis].

NMR imaging allow specific study of contrast variations due to intravascular agents. It is possible to measure regional cerebral blood volume (rCBV). In brain tumor, this parameter allow to characterize tumoral vascularisation and blood brain barrier lesions. We use today 1st pass bolus technic. Easy to perform in clinical practice, it is useful for differential diagnosis, prebiopsic planning and follow up of lesions. That should be particularly interesting to evaluate the anti-angiogenic treatment efficiency.

Brain Neoplasms↗
PubMed1999

Effect of immunomodulators on bleomycin-induced lung injury.

BACKGROUND: The role of lymphocytes and their subpopulations in lung fibrosis is as yet unclear. OBJECTIVE: To define the role of immunomodulation in bleomycin-induced inflammatory fibrotic lung injury, by testing the effect of two known Th1 inhibitors: linomide and pentoxifylline. METHODS: C57BL/6 mice were treated by a single intratracheal instillation of 0.06 mg bleomycin in 0.01 ml saline or saline alone. Treatment groups included: (1) intratracheal bleomycin and daily treatment with linomide or pentoxifylline; (2) intratracheal bleomycin and daily water; (3) intratracheal saline and daily linomide or pentoxifylline; (4) intratracheal saline and daily water. Linomide and pentoxifylline were available per os in the drinking water from 1 day prior to intratracheal instillation. Animals were studied 14 days after intratracheal instillation. Lung injury was evaluated by total and differential cell count in bronchoalveolar lavage fluid, by a semiquantitative morphological index of lung injury and a quantitative image analysis of cellularity, fibrosis fraction and alveolar wall area fraction, and by biochemical analysis of lung hydroxyproline content. RESULTS: Linomide or pentoxifylline did not cause any lung injury in saline-treated control mice. Overt signs of lung injury were apparent in bleomycin-treated mice. These changes were not affected by daily treatment with linomide or pentoxifylline, which were given in the highest tolerable dose. CONCLUSION: This study does not support the use of linomide or pentoxifylline to prevent or ameliorate lung fibrosis and may suggest that drug-induced differentiation of T lymphocytes into Th1/th2 subpopulations does not affect the evolution of bleomycin-induced lung injury.

Adjuvants, Immunologic↗
PubMed1999

The expanding role of ultrasound in medicine.

BACKGROUND: Exciting advances have occurred in ultrasound during recent years, reflecting improved computer and transducer technology. OBJECTIVE: This article discusses the expanding role of ultrasound in diagnostic and interventional imaging. Increased spatial and contrast resolution through better transducers and the use of technology, such as harmonic imaging and better colour and power Doppler imaging, facilitate diagnosis. Recent advances are discussed and limitations are outlined. DISCUSSION: Improvements in diagnosis and intervention with ultrasound confirms the place of ultrasound in the management of patients.

Female↗
PubMed1997

1-Methoxypyrene and 1,6-dimethoxypyrene: two novel metabolites in fungal metabolism of polycyclic aromatic hydrocarbons.

The metabolism of pyrene by Penicillium glabrum strain TW 9424, a strain isolated from a site contaminated with polycyclic aromatic hydrocarbons (PAHs) was investigated in submerged cultures. The metabolites formed were identified as 1-hydroxypyrene, 1,6- and 1, 8-dihydroxypyrene, 1,6- and 1,8-pyrenequinone, and 1-pyrenyl sulfate. In addition, two new metabolites were isolated and identified by UV, 1H nuclear magnetic resonance, and mass spectroscopy as 1-methoxypyrene and 1,6-dimethoxypyrene. Experiments with [methyl-3H]S-adenosyl-l-methionine (SAM) revealed that SAM is the coenzyme that provides the methyl group for the methyltransferase involved. To our knowledge, this is the first time that methoxylated metabolites of PAHs have been isolated from fungal cultures.

Biodegradation, Environmental↗
PubMed1996

Transformation and mineralization of halophenols by Penicillium simplicissimum SK9117.

The metabolism of monohalophenols by Penicillium simplicissimum SK9117, isolated from a sewage plant was investigated. In submerged cultures, 3-, 4-chlorophenol, and 4-bromophenol were metabolized in the presence of phenol. 3-Chlorophenol was transformed to chlorohydroquinone, 4-chlorocatechol, 4-chloro-1,2,3-trihydroxybenzene, and 5-chloro-1,2,3-trihydroxybenzene. With 4-chlorophenol only 4-chlorocatechol was observed as transient product. A release of chloride ions was not observed. Whereas monobromo-, and monochlorophenols could not support growth as sole carbon and energy source, growth and release of fluoride ions were observed with monofluorophenols as substrates. In presence of phenol, the degradation of all monofluorophenols was enhanced. Substrate and cosubstrate disappeared simultaneously. 3-Fluorophenol and 4-fluorophenol were completely mineralized as shown by the equimolar release of fluoride ions.

Biodegradation, Environmental↗
PubMed1995

The role of career pathway before medical school in graduates' choice of primary care versus other specialty practices.

PURPOSE: To analyze the difference, if any, in the choices of primary care versus other specialty practices among graduates of the Albany Medical College who took one of three career pathways before entering medical school and who had entered primary care residencies. METHOD: Questionnaires were mailed in April 1992 to all 458 graduates from the classes of 1980 through 1985 who had entered primary care residencies (i.e., residencies in family practice, general internal medicine, general pediatrics, or medicine--pediatrics). The graduates had followed one of three pathways to admission: (1) after completion of four years of college, (2) after completion of the six-year biomedical program in conjunction with the Rensselaer Polytechnic Institute (RPI), and (3) after having pursued a nonmedical career and being older than 25 years of age. Logistics regression was the primary vehicle for analysis, defining career choice as the dependent variable and using the independent variables of sex, year of graduation, and pathway as well as their interactions for a saturated-model analysis. RESULTS: A total of 318 graduates (69%) responded. Among the three pathways, there was no statistically significant difference in the choices of primary care versus other specialty practices. However, in the RPI and age-greater-than-25 groups, there was a greater tendency for men to choose other specialties. CONCLUSIONS: The three career pathways before medical school did not appear to have a role in the choice of primary care versus other specialty practices among graduates who had entered primary care residencies. However, gender did influence this choice.

Adult↗
PubMed1994

Metabolism of the polycyclic aromatic hydrocarbon pyrene by Aspergillus niger SK 9317.

The metabolism of pyrene, a polycyclic aromatic hydrocarbon consisting of four rings, by Aspergillus niger SK 9317 was investigated. The metabolites formed were isolated and identified as 1-hydroxypyrene, 1,6- and 1,8-pyrenequinone, 1,6- and 1,8-dihydroxypyrene, 1-pyrenyl sulphate and 1-hydroxy-8-pyrenyl sulphate. This is the first report of 1-hydroxy-8-pyrenyl as a metabolite in the microbial metabolism of pyrene. The results suggest that A. niger metabolizes pyrene by cytochrome P-450 monooxygenase enzyme systems.

Aspergillus niger↗