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J Walecki

Publications and source records attributed to J Walecki.

At least 19 recordsLinked to original sources
PubMed2006

Improved early stroke detection: wavelet-based perception enhancement of computerized tomography exams.

Nonenhanced computerized tomography (CT) exams were used to detect acute stroke by notification of hypodense area. Infarction perception improvement by data denoising and local contrast enhancement in multi-scale domain was proposed. The wavelet-based image processing method enhanced the subtlest signs of hypodensity, which were often invisible in standard CT scan review. Thus improved detection efficiency of perceptual ischemic changes was investigated. Data processing became more effective by initial segmentation of brain tissue and extraction of regions susceptible to tissue density changes. The new method was experimentally verified. Sensitivity of stroke diagnosis increased to 56.3% in comparison to 12.5% of standard CT scan preview.

Acute Disease↗
PubMed2005

The effect of risperidone on metabolite measures in the frontal lobe, temporal lobe, and thalamus in schizophrenic patients. A proton magnetic resonance spectroscopy (1H MRS).

OBJECTIVE: The aim of the study was the evaluation of risperidone effect on metabolite measures in the frontal lobe, temporal lobe and thalamus in schizophrenic patients on the basis of proton magnetic resonance spectroscopy ( (1)H MRS). METHODS: A group of 14 patients with the diagnosis of schizophrenia, according to DSM-IV, were examined in the study. The patients were examined twice, once after a period of at least 7 days without neuroleptics and for the second time at least 4 weeks after stable risperidone doses. RESULTS: The significant differences in the metabolite levels before and after the treatment were observed only in thalamus: an increase in myoinositol (mI) and N-acetylaspartate (NAA) levels. Positive symptoms before the treatment correlated positively with NAA level in the frontal lobes and negatively in the temporal lobes. Negative symptoms before the treatment correlated positively with Glx (a common signal for GABA, glutamine and glutamate) level in the temporal lobes. CONCLUSION: Our results seem to confirm the influence of risperidone on the brain metabolism, specifically in the region of thalamus.

Adult↗
PubMed2005

Beta thromboglobulin and platelet factor 4 in bronchoalveolar lavage fluid of patients with systemic sclerosis.

OBJECTIVE: To evaluate concentrations of the platelet activation markers beta thromboglobulin (BTG) and platelet factor 4 (PF4) in bronchoalveolar lavage fluid (BALF) from patients with systemic sclerosis with and without scleroderma interstitial lung disease (SLD). METHODS: BTG and PF-4 were measured by enzyme immunoassay in BALF from 37 patients with systemic sclerosis. Controls were 10 healthy subjects. BALF was collected during routine bronchoscopy from the right middle lobe. SLD was diagnosed by high resolution computed tomography of the lungs. RESULTS: BTG was detected in 11 of the patients with systemic sclerosis (29.7%) and PF4 was found in eight (21.6%). Mean (SD) concentrations of BTG and PF4 in BALF from patients with detectable levels of these platelet activation markers were 106.9 (69.8) and 35.2 (17.4) IU/ml, respectively. The BTG:PF4 ratio was more than 2:1, indicating in vivo release. Both markers were found exclusively in patients with SLD. SLD patients with detectable platelet activation markers had a significantly shorter disease duration than those with undetectable BTG/PF4. CONCLUSIONS: The study provides evidence that activation of blood platelets takes place within the lungs of patients with SLD and may contribute to the development of lung fibrosis.

Adult↗
PubMed2004

Metabolic disturbances in liver 1H MR spectroscopy in HIV and HCV co-infected patients as a potential marker of hepatocyte activation.

PURPOSE: To evaluate proton magnetic resonance spectroscopy (1H MRS) features in order to assess hepatocellular activation in chronic hepatitis C and human immunodeficiency virus/hepatitis C (HIV/HCV) co-infected patients. MATERIAL AND METHODS: Liver in vivo 1H MR spectra were obtained in 14 patients with hepatitis C virus infection (HCV), 20 HIV/HCV co-infected individuals, and 24 healthy volunteers. Resonances of lipids, glutamine/glutamate (Glx), phosphomonoesters (PME), glycogen/glucose (Glc) were assessed and metabolite ratios to total lipids (TL) were calculated. RESULTS: A significant increase in Glx/TL and PME/TL was observed in the HCV group as compared to healthy individuals. Patients with HIV and HCV co-infection had a further increase of all metabolite ratios. Changes in metabolite ratios were due to both the increase in particular metabolite contents and to the decrease in lipid levels. HIV/HCV-infected patients treated with highly active anti-retroviral therapy (HAART) showed elevated PME and Glx levels and significantly decreased TL compared to patients not undergoing anti-retroviral treatment. CONCLUSIONS: Our findings suggest clinical usefulness of liver 1H MR spectroscopy in detecting even slight disturbances in liver metabolism.

Adult↗
PubMed2003

Proton MR spectroscopy in neuroborreliosis: a preliminary study.

We report results of a magnetic resonance spectroscopy (MRS) study in 12 patients with neuroborreliosis. We used a PRESS sequence, placing an 8 cm3 voxel in normal-appearing white matter of the frontal lobe. Peaks indicating N-acetylaspartate (NAA), choline (Cho), creatine (Cr), myo-inositol (mI), lipids (Lip) and lactate (Lac) were identified and ratios of NAA/Cr, Cho/Cr, mI/Cr, Lip/Cr, Lac/Cr calculated. Significant increases in Cho/Cr and Lip/Cr were noted. No abnormality was found in mean NAA/Cr and Lac/Cr, but in four patients there was a decreased NAA peak; mI/Cr ratio was slightly increased. Although the spectroscopic profile in patients with neuroborreliosis seems to be nonspecific, MRS might be useful for assessing tissue damage of the central nervous system.

Adult↗
PubMed2003

Is there any relation between thyroid gland function and kidney transplant function?

INTRODUCTION: Patients with chronic renal failure exhibit abnormalities of thyroid function. Reports regarding thyroid function in kidney transplant recipients (TX) are rare, particularly those individuals on long-term immunosuppression. The aim of this study was to investigate correlations between FT3, FT4, TSH concentrations, thyroid volume, and graft function. MATERIAL AND METHODS: The study enrolled 46 kidney allograft recipients (aged 27-67 years,) engrafted between years 1994 and 2000 and clinically stable. The mean time after TX was 45.3 +/- 37.4 months. Transplanted patients received prednisone, cyclosporine, and azathioprine. The control group included 22 patients with normal renal function. In addition to serum creatinine, TSH, FT3, and FT4 concentrations, thyroid examinations were performed with a 7.5-MHz linear probe to calculated the thyroid volume. RESULTS: Thyroid volume in TX patients was 25.3 +/- 13.3 mL. A positive correlation existed between thyroid volume and serum creatinine (P <.05), and a negative one between thyroid volume and TSH (P <.05). No correlation was observed between TSH, FT4, and serum creatinine. The time after TX was negatively related to TSH (P <.05). A negative correlation existed also between FT3 and creatinine in TX patients (P <.05). In the control group the concentrations of TSH and FT3 were within normal ranges. CONCLUSION: The FT3 concentration correlates with function of the renal graft. In TX patients the supplementary thyroid hormone therapy should be considered.

Adult↗
PubMed2003

Assessment of fetal distress based on magnetic resonance examinations: preliminary report.

RATIONALE AND OBJECTIVES: Hypoxia is the main cause of injuries and intrauterine death of the fetus. Therefore, the main aim of monitoring and assessment of the fetus should be diagnosis of fetal distress before irreversible changes occur. Besides the fetal condition assessment methods used so far, in recent years in obstetrics new non-invasive imaging methods were introduced such as magnetic resonance (MR). This method enables morphologic evaluation of brain and brain tissue metabolism using magnetic resonance spectroscopy (MRS). MATERIALS AND METHODS: Twenty pregnant women with pregnancy-induced hypertension (11 cases, including 3 with coexisting diabetes mellitus and 2 with intrauterine growth retardation), chronic hypertension (2 cases), gestational diabetes mellitus (6 cases), and suspected intrauterine fetal growth retardation (IUGR) participated in the study. Cardiotocography (CTG) and Doppler ultrasound examination of the blood flow in the umbilical artery and in the middle cerebral artery were performed. RESULTS: In case of abnormal CTG and Doppler study records that indicated fetal hypoxia, MR studies showed the existence of ischemic focus in 5 patients and abnormal spectral images in 6 patients. CONCLUSION: The results of the preliminary study suggests that the use of MR in prenatal diagnosis may revolutionize the early detection of fetal injury in fetal distress. It is a valuable component of the diagnostic process, supplementing other examinations. The use of MR to assess fetal condition gives additional information and helps to make decisions about therapeutic actions.

Adult↗
PubMed2003

Cerebral MR spectroscopy in neurologically asymptomatic HIV-infected patients.

PURPOSE: To detect early metabolic changes in the brain of neurologically asymptomatic HIV-infected patients with normal MR imaging and to find the correlation between 1H MR results and immune status. MATERIAL AND METHODS: Twenty neurologically asymptomatic HIV seropositive patients underwent MR imaging and single-voxel 1H MR spectroscopy (MRS) using a PRESS sequence. For all patients, the signals from N-acetyl-aspartate (NAA), choline-containing compounds (Cho), creatine-phosphocreatine (Cr) and myoinositol (mI) were compared with 32 healthy volunteers as metabolite ratios and metabolite areas to non-suppressed water area ratios. RESULTS: In HIV patients, the NAA/Cho ratio was significantly lower ( p < 0.01), but there were no changes in NAA/Cr ratio. A statistically significant reduction in NAA/H2O and Cr/H2O (both p < 0.05) was observed. For the immune status there was a statistically significant correlation (r=0.47, p<0.05) between CD4 counts and NAA/H2O ratio. A significant increase in Cho/Cr ( p<0.001) and mI/Cr ( p<0.01) ratios in HIV patients was found, but Cho/H2O and mI/H2O concentrations were non-significantly increased. CONCLUSION: These results indicate that neuronal loss and gliosis in HIV-infected patients may be associated with impairment of energy metabolism. The spectral changes found suggest that 1H MRS can be used for early detection of brain damage induced by HIV.

Adult↗
PubMed2001

Menkes' disease with a Dandy-Walker variant: case report.

We report a boy with Menkes' disease in whom MRI revealed delayed myelination of the white matter, brain atrophy and tortuosity of the intracranial vessels. The characteristic MRI features of Menkes' disease were accompanied by a Dandy-Walker variant.

Brain↗
PubMed2001

MRI in nonketotic hyperglycinaemia: case report.

We present a girl with proven nonketotic hyperglycinaemia. The pathological findings on MRI were brain atrophy with thinning of the corpus callosum and delayed myelination of the cerebral hemispheres, particularly the parietal lobes.

Corpus Callosum↗
PubMed2001

MR imaging of seven presumed cases of central pontine and extrapontine myelinolysis.

MRI was performed in seven patients with presumed central pontine and extrapontine myelinolysis. The underlying diseases were diabetes, lung cancer, Wilson disease, trauma, alcoholism, renal insufficiency and hemodialysis. CPM was found in four cases (in two of them extrapontine lesions were considered as resulting from Wilson disease), CPM and EPM in three patients. The localization of extrapontine changes included cerebellum, cerebral peduncles, caudate and lentiform nuclei, internal capsules, white matter and cortex of the cerebrum.

Adolescent↗
PubMed2001

Metabolite ratios measured with a short echo time 1H-MRS in the frontal lobe of young healthy subjects: an approach to generate reference 1H-MRS data.

Proton magnetic resonance spectroscopy (1H-MRS) performed with a semi-automated Elscint Prestige 2 Tesla tomograph/spectroscope was used to determine the ratios of the most prominent resonances recorded from the 2 x 2 x 2 cm voxels located in the frontal lobe of healthy young males and females. The values of major metabolite ratios (NAA/Cr, Cho/Cr and ml/Cr) were normally distributed and comparable to results reported by other groups using advanced automated equipment. The coefficients of variation were smaller when the composed metabolite ratios (i.e. the ratios of a given resonance signal to the sum of all signals considered) were calculated. The composed metabolite ratios approach may be more sensitive for discrimination between normal and pathologically changed brain.

Adult↗
PubMed2001

Three-dimensional sonography in the diagnosis of hepatic hemangiomas.

The purpose of the study was to compare power 3-D with conventional 2-D sonography with color and power Doppler in assessment of tumor vascularity in small hepatic hemangiomas. The study group comprised 12 patients (7 males and 5 females) aged 28-60, (mean 44) with diagnosed hemangiomas. In all the patients 2-D and 3-D sonography was performed and their results were compared. Both color and power Doppler 2-D sonography failed to detect blood flow in the tumors. Blood flow signals were detected in 3-D power Doppler sonography. 3-D power Doppler is superior to 2-D color and power Doppler imaging in the detection of blood flow signal in hemangiomas.

Adult↗
PubMed2001

[Magnetic resonance proton spectroscopy in neurooncology--preliminary report].

UNLABELLED: MR proton spectroscopy (1H MRS) has been widely applied in characterisation and differentiation of brain tumors, staging, recurrence of pathologic process, post radiotherapy changes and other lesions mimicking neoplasm like abscesses. Despite of many studies performed over last 3 years in many countries spectroscopic pattern (phenotype) of brain tumors is still not well estimated and the role of each metabolite as an indicator of histopathologic grade and type of the tumor is still unknown. MATERIALS AND METHODS: In vivo 1H MR spectroscopy was prospectively performed in 36 patients with intracranial tumors (low grade gliomas, high grade gliomas, meningiomas and abscesses). Examinations was performed with 1.5 T system, using voxels of 8 cc. RESULTS: In high grade gliomas level of NAA was decreased, and consequently low ratios of NAA to other metabolites were obtained; lactate and choline peaks were markedly increased. In patients with meningiomas signal of NAA was reduced, while in abscesses group peaks of acetate and succinate were observed. Authors analysed ratios of metabolites in above-mentioned tumors. The method is especially useful in differential diagnosis in neoplastic and nonneoplastic cases. CONCLUSIONS: Our study confirms diagnostic value of 1H MRS in doubtful cases of intracranial tumors.

Brain Abscess↗
PubMed2001

[New imaging diagnostics of liver echinococcosis].

Cystic and alveolar echinococcosis, parasitic diseases, caused in humans by the larval stage of tapeworm Echinococcus granulosus and E. multilocularis are rare diseases in Poland. We have diagnosed 71 patients with cystic echinococcosis and 10 patients with alveolar echinococcosis during last 12 years. Echinococcosis still create significant diagnostic difficulties, particularly alveolar one. Progress and actually available radiological imaging techniques, which can be applied in the cystic and alveolar echinococcosis diagnostics, are presented. Ultrasound appearance, CT, MRI images are described. Own experience with Proton Magnetic Resonans Spectroscopy in two patients with recurrent alveolar echinococcosis are presented.

Animals↗