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1.
Nanotechnology ; 33(49)2022 Sep 21.
Article in English | MEDLINE | ID: mdl-36067708

ABSTRACT

Materials exhibiting an exchange bias effect are a class of magnetic systems that have a wide range of possible technological applications e.g. in sensors, read heads, and spintronic devices. In this study, we demonstrate the effect of laser interference patterning on the magnetic properties of Pd/CoO/Co/Pd multilayers. Laser patterning creates arrays of well-ordered stripes, rectangles, and squares on the substrate surface. We found that the laser treatment caused magnetic softening of the structure edges while the centers of the objects remained unchanged and exhibited the exchange bias effect. In this study we focused on the shape and configurational magnetic anisotropies induced by patterning and showed that the magnetic properties varied depending on the angle at which the external magnetic field was applied with respect to the pattern geometry.

2.
Nanotechnology ; 28(8): 085302, 2017 Feb 24.
Article in English | MEDLINE | ID: mdl-28045378

ABSTRACT

We have studied the transition between two different magnetization reversal mechanisms for thin Co/Pd multilayers with perpendicular magnetic anisotropy, appearing in magnetic dot and antidot arrays, which were prepared by nanosphere lithography. Various ordered arrays of nanostuctures, both magnetic dots and antidots, were created by varying size and distance between the nanospheres employing RF-plasma etching. We have shown that the coercivity values reach a maximum for the array of antidots with a separation length close to the domain wall width. In this case, each area between three adjacent holes corresponds to a single domain configuration, which can be switched individually. On the contrary, small hole sizes and large volume of material between them results in domain wall propagation throughout the system accompanied by strong domain wall pinning at the holes. We have also shown the impact of edge effects on the magnetic anisotropy energy.

3.
Nanotechnology ; 26(42): 425301, 2015 Oct 23.
Article in English | MEDLINE | ID: mdl-26422608

ABSTRACT

Ordered FePdCu nanoisland arrays were formed by annealing at 600 °C, which caused solid state dewetting of [Cu/Fe/Pd] multilayers deposited on self-assembled SiO2 nanospheres with a size of 100 nm. A single FePdCu island was formed on the top of each SiO2 nanosphere. The structure of the obtained system was studied by x-ray diffraction (XRD), while its magnetic properties were studied by SQUID magnetometry. A partially ordered L10 alloy appeared in the annealed films, leading to magnetic hardening of the material. The paper presents the influence of the patterning on the system properties. It is shown that templated dewetting is a method providing nanoislands with well-controlled sizes and positions. The role of copper admixture in controlling the structural and magnetic properties is also discussed.

4.
Acta Biochim Pol ; 48(4): 1085-90, 2001.
Article in English | MEDLINE | ID: mdl-11995970

ABSTRACT

An approximately threefold increase in glycogenolytic activity of the neutral alpha-1,4-glucosidase and a twofold increase in the same activity of the acid isoform have been found in extracts of anaplastic astrocytoma and glioblastoma multiforme tumors of brain tissue. "Maltase activity" of the respective enzymes increased by 60-80% in both kinds of tumor extracts. However a significant decrease in a-amylase and almost complete disappearance of phosphorylase activities have also been found in both kinds of tumors.


Subject(s)
Astrocytoma/enzymology , Brain Neoplasms/enzymology , Glioblastoma/enzymology , alpha-Amylases/biosynthesis , alpha-Glucosidases/biosynthesis , Calibration , Humans , Hydrogen-Ion Concentration , Phosphorylation , Protein Isoforms
5.
Postepy Hig Med Dosw ; 52(6): 637-54, 1998.
Article in Polish | MEDLINE | ID: mdl-10093481

ABSTRACT

In the article we discuss the role of serotonin in maintaining homeostasis paying special attention to the endocrinological aspect of the matter. It has been proved that it contributes to hypothalamus and hypophysis secretion regulation and interferes with paracrine activity in digestive and reproductive system. It is also an important constituent of platelets and takes part in aggregation and coagulation. It is known to be an atherogenic factor and to act as a growth stimulator for blood cells. It can be produced in exceed amounts by neoplasm or be released by activated thrombocytes during stress or coagulation. The influence of this hormone on the most of regulation mechanisms seems obvious. Presence of many different receptors as well as their number in all the structures of mammalian body makes it possible to use a range of agonists and antagonists in research concerning psychiatric diseases (e.g. bulimia, anorexia, depression), Alzheimer disease, migraine, hypertension, carcinoid related syndrome, multiple endocrine neoplasms and pre-menstrual syndrome. The promising results enable to use some of the modifiers in their clinical treatment though more research is needed for fully satisfactory effects.


Subject(s)
Serotonin/chemistry , Serotonin/physiology , Animals , Blood Coagulation/physiology , Brain Diseases/physiopathology , Cardiovascular Physiological Phenomena , Endocrine System/physiology , Female , Homeostasis/physiology , Humans , Male , Mental Disorders/physiopathology , Neoplasms/metabolism , Serotonin/therapeutic use
6.
Cancer Biother Radiopharm ; 11(3): 169-76, 1996 Jun.
Article in English | MEDLINE | ID: mdl-10851534

ABSTRACT

Role of cysteine endopeptidases in cancerogenesis steps: neoplastic transformation, invasion and metastasis is reviewed and discussed. Positive correlation between tumor invasiveness, as well as its metastatic potential and secretion of cysteine endopeptidase (particularly cathepsins B and L) has been documented well in literature. Based on our recent results we postulate that serum endopeptidase-like activity could be used as a marker of cancer aggressiveness in diagnostic procedures in oncology. We also propose that the cysteine endopeptidase inhibitor levels (total, active and latent) could be useful factors for recognising the activation of the organism self-defence mechanisms against cancer. In addition, our idea of use of urinary cysteine peptidase inhibitors (UCPI) as potential anticancer agents is presented and discussed.


Subject(s)
Cysteine Endopeptidases/physiology , Neoplasms/etiology , Cell Transformation, Neoplastic , Humans , Neoplasm Invasiveness , Neoplasm Metastasis , Neoplasms/enzymology
7.
Otolaryngol Pol ; 49(5): 468-74, 1995.
Article in Polish | MEDLINE | ID: mdl-8714573

ABSTRACT

Pneumocephalus or intracranial air its commonly detected following serious head injury and posterior fossa surgery. In laryngology the frequent reason of its appearance is also herniation of air through a break in the wall of skull due to advanced benign and malignant tumors. The pathophysiology involves the presence of craniodural fistula allowing ingress of air. A ballvalve mechanism may allow air to enter not exit the cranium or like in turned upside down bottle leak permit air entrance as fluid leaves the intracranial space. The presence of air is usually asymptomatic but caries a potential risk of increased intracranial pressure or meningitis which require an immediate therapy. Although various ways of treatment were reported prevention and early diagnosis are the most important. We report 3 cases of cerebral air that occurred secondary to the head trauma. The diagnosis every time promptly confirmed by skull roentgenogram or CT.


Subject(s)
Facial Injuries/complications , Pneumocephalus/etiology , Adult , Craniocerebral Trauma/complications , Facial Injuries/diagnosis , Female , Humans , Male , Middle Aged , Pneumocephalus/diagnosis , Tomography, X-Ray Computed
8.
Neurol Neurochir Pol ; 26(2): 232-8, 1992.
Article in Polish | MEDLINE | ID: mdl-1528382

ABSTRACT

Tumour origin and evolution currently is viewed as comprising a series of specific genetic events that take place in target cells and their clonal descendants. These events can be recognized at two levels: cytogenetic and molecular. The genetic results can be used as diagnostic and prognostic markers of neoplastic diseases. However, till now reports on the karyotypic characteristics of brain tumors are far from numerous. The most frequent cytogenetic alterations observed in primary brain tumors are losses or gains of chromosomes or chromosomal regions and presence of double minute chromosomes. Enhanced expression of several cellular oncogenes on human glioma cells lines were observed also.


Subject(s)
Brain Neoplasms/genetics , Chromosome Deletion , Chromosomes, Human, Pair 1 , Chromosomes, Human, Pair 6 , Chromosomes, Human, Pair 7 , Chromosomes, Human, Pair 9 , Gene Expression Regulation, Neoplastic/physiology , Glioma/genetics , Oncogenes/genetics , Brain Neoplasms/etiology , Glioma/etiology , Humans , Oncogenes/physiology
9.
Pol Tyg Lek ; 44(27): 632-4, 1989 Jul 03.
Article in Polish | MEDLINE | ID: mdl-2637433

ABSTRACT

The 35 patients with bronchial asthma undergoing continuous steroid therapy were examined in order to reveal any signs of steroid myopathy. More than 80% of patients complained of muscle weakness. In the physical examination the motor function was correct in the majority of patients. Muscular enzymes and blood electrolytes were normal. EMG has shown typical myopathic changes In over 80% of patients. The diagnosis of subclinical steroid myopathy was based mainly on EMG examination. This myopathy was independent of sex, age, dose an duration of therapy.


Subject(s)
Asthma/drug therapy , Muscular Diseases/chemically induced , Steroids/adverse effects , Adolescent , Adult , Aged , Electromyography , Female , Humans , Male , Middle Aged , Steroids/administration & dosage
10.
Polim Med ; 15(1-2): 49-59, 1985.
Article in Polish | MEDLINE | ID: mdl-3900962

ABSTRACT

Significance of suture material in microchirurgical operations of nerves was the base of comparative experimental research on sutures and the reaction of tissues around the suture in early and late period. Commonly employed monophilous polyester and polyamid sutures of 9/0, 10/0 were used, as well as prototype multifilament polyester threads covered with polyurethane, and polyglicol acid threads Dexon. In the group where Dexon threads were used, 7 days after the operation the microscopic picture was the same as in the group where polyester and polyamid threads Ethilon were used. 30 days after operation the Dexon sutures changed in coloration and underwent fragmentation, after 180 days they could not be found in histological preparations. Basing on the studies it can be maintained that the use of Dexon microsurgical sutures may be a further advancement in perfecting microsurgical methods in nerve and vascular sutures.


Subject(s)
Foreign-Body Reaction/etiology , Nylons/adverse effects , Polyesters/adverse effects , Polyethylene Glycols/adverse effects , Sciatic Nerve/surgery , Sutures , Absorption , Animals , Female , Foreign-Body Reaction/pathology , Male , Microsurgery/instrumentation , Rabbits , Sciatic Nerve/pathology , Time Factors
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