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1.
Nanoscale ; 15(10): 4870-4881, 2023 Mar 09.
Article in English | MEDLINE | ID: mdl-36779233

ABSTRACT

Radiation-induced heterogeneous damage is the single largest source of failures seen in structural components in nuclear power reactors. Single crystal materials without grain boundaries, show considerable promise for overcoming this problem. In this work, such heterogeneous damage was further overcome in NixFe1-x single crystal alloys via a simple strategy of fine-tuning the composition. [001] NixFe1-x (x = 0, 0.38 and 0.62 at%) single crystals prepared using the Bridgman method were irradiated over a wide fluence range (4 × 1013 to 4 × 1015 ions per cm2). The irradiation-induced defect evolution was studied using Rutherford backscattering/channeling spectrometry, Monte Carlo simulations, transmission electron microscopy and nanoindentation. The results indicate an increased radiation tolerance of Ni0.38Fe0.62 compared to pure Ni and Ni0.62Fe0.38. The structural analysis performed by transmission electron microscopy revealed that defects tend to agglomerate at one place in Ni and Ni0.62Fe0.38, while in Ni0.38Fe0.62 no defect accumulation zone (characteristic damage peak) has been captured either at low or high fluence. Moreover, we found that the hardness change with the increase of Fe content is due to different arrangements of Fe atoms in the crystal structure, which influences the obtained mechanical properties of NixFe1-x in the pristine state and after ion implantation.

2.
Med Eng Phys ; 31(10): 1276-82, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19762270

ABSTRACT

We present single fibre heart activity model (SFHAM) based on the current flow through the five bunches of fibres of the cardiac muscle (CM). The five effective fibres are identified and assigned to the appropriate segments of CM. Analytical functions describing ionic flows along the fibres are derived and proposed. The parameters determining the shapes and amplitudes of the functions proposed are obtained on the basis of standard 12-lead ECG measurements after numerical fitting procedures concentrating on the QRS-waves. As a consequence, five independent courses of partial, transient potentials are obtained representing: anterior, inferior, lateral, posterior walls, and interventricular septum activities, respectively. Moreover, to check our theoretical results we compare the potentials calculated with those from physical measurements performed on the patient's body surface. We expect that SFHAM will permit detection of pathological changes in particular fragments of CM.


Subject(s)
Electrocardiography/methods , Heart/physiology , Myocardium/metabolism , Action Potentials , Body Surface Potential Mapping , Electrophysiology/methods , Heart Conduction System , Heart Ventricles , Humans , Ions , Models, Anatomic , Models, Theoretical , Myocardial Contraction , Signal Processing, Computer-Assisted
3.
Clin Neuropathol ; 24(6): 257-61, 2005.
Article in English | MEDLINE | ID: mdl-16320819

ABSTRACT

Meningiomas exhibit a broad spectrum of differentiation potency corresponding to different histological subtypes. The separate secretory or lipomatous transformation of meningothelial cells is uncommonly encountered in meningiomas classified into distinct secretory or lipomatous variants. The coexistence of these two different histological subtypes is extremely rare. We report an exceptional case of secretory meningioma associated with extensive lipomatous component in a 58-year-old woman. CT scan and MRI of the brain showed a well-defined tumor mass in the right temporal lobe with areas of adipose tissue and extensive surrounding brain edema. Microscopically, the tumor was composed of two components: whorls of meningothelial cells with numerous PAS-positive hyaline inclusions (pseudopsammoma bodies) and numerous mature adipocyte-like cells. The presence of neutral fat was confirmed by oil-red-O staining. The hyaline inclusions and tumor cells surrounding them showed strong immunoreactivity for EMA and CEA. Ultrastructural findings confirmed both secretory and lipomatous differentiation of tumor cells. The majority of lipidized neoplastic cells shared the features of meningothelial cells and adipocytes. Our result supports the opinion that lipomatous component ought to be considered as an advanced lipidization of neoplastic meningothelial cells rather than true metaplastic transformation of meningothelial cells into mature fat tissue. The present case of meningioma demonstrates a unique coexistence of secretory and lipomatous meningothelial components, reflecting the multipotency of phenotypic transformation of primary meningothelial cells.


Subject(s)
Meningeal Neoplasms/metabolism , Meningeal Neoplasms/pathology , Meningioma/metabolism , Meningioma/pathology , Female , Humans , Hyalin/metabolism , Lipid Metabolism , Middle Aged
4.
J Synchrotron Radiat ; 8(Pt 2): 493-5, 2001 Mar 01.
Article in English | MEDLINE | ID: mdl-11512827

ABSTRACT

Technologically important coatings of transition-metal aluminides call be produced by thermal or ion beam mixing of multilayer structures sputter deposited on substrates. The quantitative detection of constituents by depth profiling is sufficient to establish the efficiency of mixing methods. However, to decide whether a mixture of nanoparticles or a stoichiometric alloy is formed, EXAFS analysis of the local atomic neighborhood in the film is required. Ni K edge EXAFS spectra are measured on a series of samples of Ni/Al multilayer on Si(111) surface, after ion mixing at different substrate temperatures. The spectra show that with increasing temperature the nickel aluminide phase gradually substitutes the Ni fcc metal phase.

5.
Folia Neuropathol ; 39(3): 209-13, 2001.
Article in English | MEDLINE | ID: mdl-11770132

ABSTRACT

A rare case of extensively disseminating multiple benign choroid plexus papilloma is shown. The patient first reported with high-grade hydrocephalus and two tumours in the 3rd and 4th ventricle was treated by atrioventricular shunt insertion, subtotal resection of the 4th ventricle tumour, and adjuvant 60Co irradiation of the posterior fossa. The dissemination that followed was revealed by computerised tomography and magnetic resonance imaging, and involved both the supra- and infratentorial ventricular systems, spinal canal, and brain parenchyma. Three years after the resection of the 4th ventricle tumour, the patient underwent excision of a temporal lobe lesion for relief of neurological symptoms, but showed no improvement and died 5 years after the primary diagnosis of CNS tumour. An autopsy was not performed. Analysis of the primarily resected mass showed distinct papillary pattern with no anaplasia, mitoses, multinucleation orgiant cell formation, and cytokeratin positivity at the absence of vimentin and glial fibrillary acidic protein. Analysis ofthe temporal lobe tumour again showed definite papillary formation with no signs of malignisation and virtually no mitotic figures, and the presence of cytokeratin, but not vimentin or glial fibrillary acidic protein. On both occasions, the diagnosis was choroid plexus papilloma (WHO grade I).


Subject(s)
Choroid Plexus Neoplasms/pathology , Papilloma/pathology , Brain/pathology , Cell Movement , Fatal Outcome , Humans , Hydrocephalus/diagnosis , Intracranial Pressure , Magnetic Resonance Imaging , Male , Middle Aged
6.
Ginekol Pol ; 72(12): 1083-6, 2001 Dec.
Article in Polish | MEDLINE | ID: mdl-11883214

ABSTRACT

In cases of ectopic pregnancy a blood collected in a pouch of Douglas is a nonclotting one. It contains no fibrinogen, prothrombin, factor V and VII, plasminogen and monomers of fibrin, however concentration of D-dimers is very high. Is this solely an effect of independently occurring fibrinolysis or does coagulation accompany this process? The definite answer can not be given. Coagulation and fibrinolysis markers obtained at the same time from peripheral veins were normal.


Subject(s)
Blood Coagulation Factors/metabolism , Douglas' Pouch , Fibrinolysis , Pregnancy, Ectopic/blood , Adult , Biomarkers/blood , Factor V/metabolism , Factor VIII/metabolism , Female , Fibrinogen/metabolism , Humans , Plasminogen/metabolism , Pregnancy , Prothrombin/metabolism
7.
Folia Neuropathol ; 38(3): 135-41, 2000.
Article in English | MEDLINE | ID: mdl-11043975

ABSTRACT

The subject of this study is a case of anaplastic ependymoma originally arising from the central canal of the lower spinal cord followed by the 13 years history of events of upper spinal dissemination and retrograde intracranial spread. The specimens from four subsequent surgeries generally displayed the same microscopic features of neoplastic tissue and were consistent with the diagnosis of anaplastic ependymoma. The histological diagnosis was based upon the high cellularity, considerable nuclear atypia and pleomorphism, brisk mitotic activity, focally exhibited vascular endothelial proliferation and extensive necrosis. Apart from the typical pattern of ependymoma, the tumors contained areas composed almost entirely of large, uniform clear cells or pseudogemistocytes indicating the morphological heterogeneity of neoplastic cells population. The surgical specimens from four surgical resections shared light microscopic similarities suggesting spinal and intracranial dissemination from the primary spinal tumor. Since the retrograde spread via the cerebrospinal fluid (CSF) pathway is extremely rare, the authors of this study discuss the mechanism of such way of tumor metastases.


Subject(s)
Brain Neoplasms/pathology , Ependymoma/secondary , Neoplasm Invasiveness , Spinal Cord Neoplasms/secondary , Spinal Neoplasms/secondary , Adult , Fatal Outcome , Humans , Magnetic Resonance Imaging , Male
8.
Ginekol Pol ; 70(9): 610-6, 1999 Sep.
Article in Polish | MEDLINE | ID: mdl-10534924

ABSTRACT

Turner Syndrome (TS) is the only one monosomy that occurrs+ in humans. The cytogenetics of TS is very well known from years. It has been estimated that almost 98-99% of TS foetuses end in abortion. It was suggested that the monosomy arises relatively late during embryonal development and survived TS individuals could be mosaics. It has been proved that mosaic karyotype mos 45,X/46X, + mar(Y) occurrs++ in 2% to 11% of TS patients. The patients having additional cell line containing der(Y) are at increased risk of gonadoblastoma development. In these cases gonadectomy should be considered. Therefore detection of mosaic and establishing the origin of marker chromosome (specially containing Y-specific sequences) is of special importance. The aim of present study was to detect the small mosaics, containing mar(Y) in TS patients, by using PCR and FISH techniques. Eight Y sequences for the PCR analyses as well as bicolor in situ hybridisation with painting probes for Y and X chromosomes have been applied. The positive amplification for Y-specific sequences has been detected in 7% of TS patients. Our results support the thesis that searching for the Y sequences should be introduced to routine genetic TS diagnosis.


Subject(s)
Turner Syndrome/genetics , Y Chromosome/genetics , Adolescent , Chromosome Deletion , Female , Humans , Infant , Karyotyping , Sequence Analysis, DNA , X Chromosome/genetics
9.
J Neurooncol ; 41(2): 175-80, 1999 Jan.
Article in English | MEDLINE | ID: mdl-10222438

ABSTRACT

Reduced blood cholesterol levels were reported in patients with a variety of malignant peripheral tumors. This fact is likely related to increased cholesterol demand by proliferating tumor cells. The question arises whether this 'tumor-associated hypocholesterolemia' occurs also in patients with brain tumors, and--if it does not--whether its absence can be related to the location of the tumors. We have compared fasting serum total cholesterol levels among three groups of patients: 52 patients with gliomas, 56 patients with symptomatic metastatic brain tumors, and 50 patients harboring malignant tumors of peripheral location but showing no clinical signs of brain metastases. Patients in the last group, despite being--on an average--more age-advanced, had lower total serum cholesterol levels than either the patients with gliomas, or the patients with brain metastases. No difference in the cholesterol levels was found between the two latter groups, and a majority of these patients had borderline or elevated cholesterol levels. This apparent absence of 'tumor-associated hypocholesterolemia' in brain tumor patients may be related to either brain tumors' ability to synthesize cholesterol de novo and their reduced dependence on peripheral cholesterol supply, the existence of brain tumor-blood barrier, effect of medications used to counteract brain edema and seizures, or a combination of these factors.


Subject(s)
Brain Neoplasms/blood , Brain Neoplasms/secondary , Cholesterol/blood , Glioma/blood , Neoplasms/blood , Adult , Aged , Aged, 80 and over , Aging/blood , Analysis of Variance , Fasting/blood , Humans , Middle Aged
10.
Int J Mol Med ; 1(3): 569-71, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9852264

ABSTRACT

We report the characterization by traditional cytogenetic methods and fluorescence in situ hybridization (FISH) of a rare balanced reciprocal translocation t(3;21) in a male spouse connected with several miscarriages. G- and C-banding analysis of the male karyotype was suggestive of breakpoints in chromosomal bands 3q11.1 and 21p11.1. Multicolor-FISH analysis using chromosome-specific alpha-satellite probes in combination with a locus-specific bacterial artificial chromosome (BAC) from 21q22.3 allowed us both to identify the origin of centromeres in the derivative chromosomes and to establish centromere-telomere orientation of the translocated chromosome 21 segment. Characterization of the translocated chromosomes by FISH analysis permitted describing the exact karyotype of the carrier as: 46,XY,-3,-21,+der(3)(21qterO21q11. 2::3p11.2O cenO3qter),+der(21)(3pterO3p11.2::21q11.2OcenO21pte r).


Subject(s)
Chromosomes, Human, Pair 21/genetics , Chromosomes, Human, Pair 3/genetics , Translocation, Genetic , Abortion, Spontaneous , Adult , Fathers , Female , Humans , In Situ Hybridization, Fluorescence , Karyotyping , Male , Pregnancy
12.
Ginekol Pol ; 69(3): 133-8, 1998 Mar.
Article in Polish | MEDLINE | ID: mdl-9639978

ABSTRACT

Androgen insensitivity syndrome (AIS) is caused by mutation in androgen receptor (AR) gene. This phenomenon leads to the defect of the virilization of the external genitalia and is one of the causes of human male pseudohermaphroditism. Molecular diagnosis of AR gene mutations is very complex because of heterogeneity of AR mutations. AIS is X-linked recessive trait and therefore the simple diagnosis of AIS carriers is a very important problem. Detection of AIS carriers by using the analysis of CAG repeating sequence polymorphism of exon 1 or AR gene is reported.


Subject(s)
Androgen-Insensitivity Syndrome/genetics , Androgens/genetics , Genetic Carrier Screening/methods , Polymorphism, Genetic/genetics , Receptors, Androgen/genetics , Trinucleotide Repeats/genetics , Adult , Androgen-Insensitivity Syndrome/diagnosis , Female , Genetic Testing , Humans , Male , Pedigree
13.
Folia Neuropathol ; 36(4): 239-43, 1998.
Article in English | MEDLINE | ID: mdl-10079608

ABSTRACT

Three cases of multilocular parasitic brain cysts are presented; two cases of specific form of neurocysticercosis and one case of multilocular hydatid cyst. MRI shows features seen in other cystic lesions of the CNS. In all cases the diagnosis was established by neurosurgical brain biopsy. The authors indicate that the parasitic disease should be taken into consideration in differential diagnosis of tumor-like cystic brain lesions.


Subject(s)
Central Nervous System Infections/parasitology , Cysticercosis/complications , Cysts/parasitology , Echinococcosis/complications , Adult , Brain Neoplasms/diagnosis , Central Nervous System Infections/diagnosis , Central Nervous System Infections/surgery , Cysticercosis/diagnosis , Cysticercosis/surgery , Cysts/diagnosis , Cysts/surgery , Diagnosis, Differential , Echinococcosis/diagnosis , Echinococcosis/surgery , Humans , Magnetic Resonance Imaging , Male , Middle Aged
14.
Neurol Neurochir Pol ; 32(6): 1369-75, 1998.
Article in Polish | MEDLINE | ID: mdl-10358827

ABSTRACT

Visual evoked potentials (VEPs) were recorded in a group of 20 operators aged 25-45 years during two sessions, before and after a 5-hour work at computer terminals, in order to assess visual system fatigue. The outcomes were referred to the norms established for the age-matched population of 30 subjects not exposed to professional contact with computers. Most of the examined operators suffered various complaints concerning not only the organ of vision but the central nervous system as well. VEPs were elicited by means of monocular stimulation using the reversal checkerboard pattern and recorded simultaneously from the scalp electrodes placed over the right and the left cerebral hemisphere. Only recording acquired after finishing of a working day demonstrated significant statistically abnormalities of the VEPs waveforms, which suggests their transient character. The changes mentioned above included prolongation of peaks P100 and N2 latency with concomitant attenuation of their amplitudes and a decrease of the correlation coefficient values for the recordings from the hemispheres. The preliminary findings presented in this paper seem to justify a conclusion that the non-invasive VEPs method can be considered as the objective indicator of the central visual fatigue induced by the workload at computer terminals.


Subject(s)
Brain/physiology , Computers , Evoked Potentials, Visual , Fatigue/diagnosis , Fatigue/etiology , Occupational Diseases/diagnosis , Occupational Diseases/etiology , Visual Perception/physiology , Accommodation, Ocular/physiology , Adult , Electrodes , Female , Functional Laterality/physiology , Humans , Male , Middle Aged
15.
Ginekol Pol ; 68(5A): 248-52, 1997 May.
Article in Polish | MEDLINE | ID: mdl-9480240

ABSTRACT

Cytogenetic studies were performed in 129 couples with the history of recurrent spontaneous miscarriages. In 8 couples (6.2%) chromosome aberrations were found The most frequent aberrations were reciprocal translocations (in 6 couples). Pericentric inversion of chromosome 9 was detected in 3 couples (2.3%) while the chromosome polymorphism was observed in 20% of analyzed cases.


Subject(s)
Abortion, Habitual/genetics , Chromosome Aberrations/genetics , Chromosomes, Human, Pair 9 , Adult , Female , Humans , Karyotyping , Male , Polymorphism, Genetic , Pregnancy
16.
Otolaryngol Pol ; 51(3): 324-7, 1997.
Article in Polish | MEDLINE | ID: mdl-9527633

ABSTRACT

The authors described a very rare case of intraparotid Schwannoma in 39 year old female. The tumor originated from jugulare ramus at the facial nerve. The patient undergone surgical treatment.


Subject(s)
Neurilemmoma/pathology , Parotid Neoplasms/pathology , Adult , Female , Humans , Neurilemmoma/surgery , Parotid Neoplasms/surgery
17.
Neurol Neurochir Pol ; 30(6): 943-51, 1996.
Article in Polish | MEDLINE | ID: mdl-9173333

ABSTRACT

BAEPs examinations performed in healthy newborns aged up to 14 days of life revealed that in the youngest group (up to 4 days of life) the percentage of the results with delayed peak I latency was relatively high -57.8%. In the further age group (5-7 days of life) the number of the abnormal results decreased considerably down to 14.1%.


Subject(s)
Evoked Potentials, Auditory, Brain Stem , Evoked Potentials, Auditory , Hearing Disorders/diagnosis , Humans , Infant , Infant, Newborn , Neonatal Screening
18.
Pol Arch Med Wewn ; 96(3): 234-41, 1996 Sep.
Article in Polish | MEDLINE | ID: mdl-9122014

ABSTRACT

Research on body surface potential mapping concerned predominantly the ventricular excitation process. There is only very limited data available documenting surface potential distribution during atrial electric events. The goal of this study was to establish the pattern and criteria of the atrial potential maps in the healthy population, which is substantial for a prospective usefulness of the noninvasive registrations of surface maps in atrial arrhythmias. A group of 54 subjects in whom there was no clinical evidence of cardiac dysfunction underwent a procedure of body surface potential mapping. The recordings were performed using the HPM-7100 system simultaneously from 87 leads covering the entire thorax. Isopotential maps registered during the P wave were subjected to the statistical analysis by means of the own system "Heart Map" enabling the qualitative and quantitative estimation of the atrial maps. To avoid a problem of variable heart rate, a time standardization, by the division of the P wave into 10 time intervals, was applied. In order to eliminate an interindividual variability of heart location in the thorax, a distribution of the constituent values without subordinating them to the individual electrodes was proposed. In consequence, the group-mean isopotential maps of the wave P for the normal subjects were created. According to the migration of the maximum throughout the thoracic surface during the P wave, three phases of the isopotential atrial maps were determined: phase 1 (P1-P4) comprising initial 40% of the P wave, phase 2 (P5,P6)-next 20% of the P wave and phase 3 (P7-P10)-the terminal 40% of the P wave duration. These phases reflect the successive sequences of atrial excitation. During the whole atrial depolarization the minimum of potential, changing its value, was located around lead D7. Furthermore, in the results of the analysis of the constituent values sequences, for the P wave time intervals the additional quantitive parameters were calculated, i.e. areas designated by positive and negative potential and the ratio of these areas. The presented findings revealed that surface maps give the precious insight into spread of atrial excitation. Establishing of the distribution pattern and the criteria of the atrial potential maps for normals enables to undertake the further research on the use of this technique in a various atrial pathology.


Subject(s)
Atrial Function , Body Surface Potential Mapping/methods , Adult , Echocardiography , Female , Humans , Male , Prospective Studies , Reference Values
19.
Neurol Neurochir Pol ; 30(4): 599-608, 1996.
Article in Polish | MEDLINE | ID: mdl-9045062

ABSTRACT

Non-traumatic rhinorrhoea of CSF occurs much less frequently than traumatic ones. The most frequent causes of this rhinorrhoea are congenital abnormalities of the cranial bass. Non-traumatic rhinorrhoea with normal cerebrospinal fluid pressure and those with raised CSF pressure are known. In the latter rhinorrhoea is one of the signs of a disease causing CSF pressure rise. In view of the rare occurrence of nontraumatic rhinorrhoea 6 cases are reported which were treated in the years 1986-1993 in the Neurosurgery Department, Medical Academy in Warsaw.


Subject(s)
Cerebrospinal Fluid Rhinorrhea/diagnosis , Cerebrospinal Fluid Rhinorrhea/etiology , Adult , Cerebrospinal Fluid Rhinorrhea/surgery , Female , Humans , Male , Middle Aged , Recurrence , Retrospective Studies , Skull Base/abnormalities , Skull Base/surgery , Treatment Outcome
20.
Pol Arch Med Wewn ; 95(4): 289-98, 1996 Apr.
Article in Polish | MEDLINE | ID: mdl-8755834

ABSTRACT

The aim of this study was to assess the influence of sotalol hydrochloride on time- and frequency-domain parameters of signal-averaged electrocardiogram (SAECG) in patients with ischemic heart disease (IHD). The study population consisted of 25 patients (16 women and 9 men), mean age 56.6 +/- 8.3. Sotalol was orally used in dose 160 mg/day during 6 weeks. Recording of SAECG and ambulatory Holter monitoring were made at baseline and in 10 day and after 6 weeks of therapy. The following time-domain parameters were analyzed: the root mean square voltage of the last 40 and 50ms of the filtered QRS (RMS 40 i RMS 50), total time duration of filtered QRS (t-QRS) and duration of low amplitude signals < 40 microV in the terminal part of QRS (LPD). Late potentials (LP) were recognized when at least two from three criteria were fulfilled: 1) RMS40 < 20 microV, 2) t-QRS > 114 ms, 3) LPD > 38ms. Frequency analysis of SAECG allowed to calculate the following parameters in logarithmic scale: energy spectrum > -60dB (A) and decibel drop at 40 Hz (Dd) and also in linear scale: area ratio 20-50/0-20 Hz (Ar) and magnitude ratio (MR1-7). The values of RMS40 and RMS50 and also t-QRS and LPD did not significantly change after sotalol treatment. At baseline the presence of LP was recorded in 7 (28%) cases, after 10 days of antiarrhythmic therapy only in 3 (12%), and after 6 weeks occurred in 6 (24%) cases. Moreover, sotalol hydrochloride did not statistically significant change frequency-domain parameters in logarithmic scale: A and Dd. On the other hand, the parameters in linear scale: MR1, MR4 and MR6 significantly change but these changes were not uniform. These findings suggest that oral treatment of sotalol hydrochloride did not significantly change time- and frequency-domain parameters of signal-averaged electrocardiogram in patients with ischemic heart disease.


Subject(s)
Anti-Arrhythmia Agents/therapeutic use , Electrocardiography/drug effects , Myocardial Ischemia/drug therapy , Sotalol/therapeutic use , Anti-Arrhythmia Agents/pharmacology , Electrocardiography, Ambulatory , Female , Humans , Male , Middle Aged , Myocardial Ischemia/physiopathology , Sotalol/pharmacology
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