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1.
J Neuroradiol ; 50(3): 281-287, 2023 May.
Article in English | MEDLINE | ID: mdl-35385772

ABSTRACT

BACKGROUND AND PURPOSE: Classification of deep (D), superficial (S) MCA territories and their junctional vascular area (the internal border zone, IBZ) can help to identify patients most likely to benefit from aggressive reperfusion therapy after stroke. We tested the prognostic value of an IBZ injury compared to DWI-ASPECTS and infarct volume. MATERIALS AND METHODS: DW lesions of 168 patients with acute (4.2±6.5 h) MCA strokes were retrospectively examined and manually delineated. Patients with haemorrhagic transformation or other neurological diseases were excluded. Clinical data were recorded within 24 h following symptom onset and 48 h for patients who benefited from reperfusion therapy. The occurrence of an IBZ injury was determined using a standardized stereotaxic atlas. Performance to predict a good outcome (mRS<3 at 3 months) was estimated through ROC curves for DWI-ASPECTS≤6, lesion volume≥100 mL and IBZ injury. Logistic regression models were performed to estimate independent outcomes for infarct volume and IBZ injury. RESULTS: Infarcts involving the IBZ were larger (94.9±98.8 mL vs. 30.2±31.3 mL), had higher NIHSS (13.8±7.2 vs. 7.2±5.7), more frequent MCA occlusions (64.9% vs. 28.3%), and worse outcomes (mRS 3.0±1.8 vs. 1.9±1.7), and were less responsive to IVtPA (34±47% vs. 55±48% of NIHSS improvement). The area under the ROC curves was comparable between the occurrence of IBZ injury (0.651), ASPECTS≤6 (0.657) and volume≥100 mL (0.629). Logistic regression analyses showed an independent effect of an IBZ injury, especially for superficial MCA strokes and for patients who benefited from reperfusion therapy. CONCLUSION: An IBZ injury is an early and independent marker of stroke severity, functional prognosis and treatment responsiveness.


Subject(s)
Infarction, Middle Cerebral Artery , Stroke , Humans , Infarction, Middle Cerebral Artery/pathology , Retrospective Studies , Diffusion Magnetic Resonance Imaging , Stroke/diagnostic imaging , Stroke/pathology , Prognosis , Treatment Outcome
2.
Curr Health Sci J ; 45(2): 210-217, 2019.
Article in English | MEDLINE | ID: mdl-31624650

ABSTRACT

We performed a retrospective study on 30 subjects having subclinical depression in the past, involved in a psychotherapeutically process in the last 5 years, which gradually returned with a post-partum depressive episode. The subjects were between 20 and 38 years of age, without psychotic disorders, selected by psychological criteria. Our results showed that for patients' psychopathological profile we found depression, anxiety, affective instability of polymorph aspect, interpretative tendencies. These manifestations correlated significantly with profiles obtained from the Beck and Hamilton scales, often dominated by existential impasse with depressive and anxious tendencies. This study found many risk factors associated with suicidal behavior in patients with post-partum depressive disorder: age under 35, socio-familial and precarious economic status, childhood abuse, disharmonic family relationships, psychotrauma (abuse), emotional instability, accentuated personality, subclinical psychiatric suffering, a heredo-collateral history of mental illness, past history of suicide attempts, low cholesterol levels.

3.
Phys Rev Lett ; 122(15): 156601, 2019 Apr 19.
Article in English | MEDLINE | ID: mdl-31050538

ABSTRACT

We derive a closed-form expression for the weak localization (WL) corrections to the magnetoconductivity of a 2D electron system with arbitrary Rashba α and Dresselhaus ß (linear) and ß_{3} (cubic) spin-orbit interaction couplings, in a perpendicular magnetic field geometry. In a system of reference with an in-plane z[over ^] axis chosen as the high spin-symmetry direction at α=ß, we formulate a new algorithm to calculate the three independent contributions that lead to WL. The antilocalization is counterbalanced by the term associated with the spin relaxation along z[over ^], dependent only on α-ß. The other term is generated by two identical scattering modes characterized by spin-relaxation rates which are explicit functions of the orientation of the scattered momentum. Excellent agreement is found with data from GaAs quantum wells, where, in particular, our theory correctly captures the shift of the minima of the WL curves as a function of α/ß. This suggests that the anisotropy of the effective spin-relaxation rates is fundamental to understanding the effect of the spin-orbit coupling in transport.

4.
Curr Health Sci J ; 45(3): 285-290, 2019.
Article in English | MEDLINE | ID: mdl-32042456

ABSTRACT

Local inflammation plays a very important role in the apparition and development of tumors and metastasis. The objective of this study was to investigate the significance of neutrophil to lymphocyte ratio (NLR), lymphocyte to monocyte ratio (LMR) and platelet to lymphocyte ratio (PLR) in peripheral blood of patients with gastrointestinal malignant tumors. METHODS: Medical records of 145 patients diagnosed with gastrointestinal malignant tumor between January 2017 and December 2017 were analyzed retrospectively. Pretreatment neutrophil, lymphocyte, platelet and monocyte counts and NLR, LMR and PLR were investigated. RESULTS: The mean for NLR, PLR and LMR in patients with gastrointestinal cancer were determined. CONCLUSIONS: Determination of NLR, PLR and LMR can be easily done with a simple blood test and may be useful inflammatory markers as in our study we have observed the presence of increased inflammatory response in patients with gastrointestinal cancer.

5.
Curr Health Sci J ; 44(3): 311-315, 2018.
Article in English | MEDLINE | ID: mdl-30647954

ABSTRACT

A 31-year-old patient presented in the Emergency Department with a tibial fracture following a car accident that crushed the lower third of his thigh and the proximal and median part of his calf. Tibial fracture fixation with an intramedullary rod, was complicated by a Morel-Lavallée lesion. Sequential debridement procedures were performed with partially successful granulation tissue proliferation under NPWT (Negative-Pressure Wound Therapy). To further promote the already delaying granulation, plastic surgeons opted for PRP/PRF (Platelet Rich Plasma/Platelet Rich Fibrin) which allowed appropriate skin grafting. In our opinion, PRP/PRF should be considered as a viable adjuvant therapy to promote granulation.

6.
Curr Health Sci J ; 42(3): 226-230, 2016.
Article in English | MEDLINE | ID: mdl-30581576

ABSTRACT

Aim: To investigate upper GI bleeding as a particular complication in chronic kidney disease patients. Material and methhod: 30 chronic kidney disease patients admitted to the Nephrology Department for upper gastrointestinal bleeding over a period of 5 years. Results: 16 patients were undergoing hemodialysis (53.3%) and 14 patients were not in a hemodialysis program. There were no patients undergoing peritoneal dialysis. Very high comorbidity rate for all patients, most important being cardiovascular diseases. Only 10% of patients had oral anticoagulant treatment prior to GI bleeding. Conservative treatment was successful for all patients; no endoscopic or surgical haemostasis was needed. Conclusion: Although chronic disease kidney patients have a high risk of upper GI bleeding compared to the general population, the conservative treatment applied has a very high rate of success in stopping the bleeding without the need for endoscopic or surgical haemostasis treatment.

7.
Curr Health Sci J ; 42(4): 408-412, 2016.
Article in English | MEDLINE | ID: mdl-30581596

ABSTRACT

Hereditary spherocytosis (HS) represents the most frequent hemolytic anemia in Central and Northern Europe consisting in an inherited abnormality of the red blood cell (RBC) membrane. It is usually transmitted as an autosomal dominant disorder; 25% of cases are without family history. Splenectomy is the classical conception and it can cure hemolysis, being the treatment of choice for moderate to severe forms of HS. A new approach is accepted nowadays, subtotal splenectomy, thus eliminating the lifelong risk of postsplenectomy infections. We present two cases of HS treated by subtotal splenectomy, alongside the advantages and disadvantages of this therapy.

8.
J Phys Condens Matter ; 27(22): 225303, 2015 Jun 10.
Article in English | MEDLINE | ID: mdl-25984760

ABSTRACT

We show that the Landau bands obtained in a two-dimensional lateral semiconductor superlattice with spin-orbit coupling (SOC) of the Rashba/Dresselhaus type, linear in the electron momentum, placed in a tilted magnetic field, do not follow the symmetry of the spatial modulation. Moreover, this phenomenology is found to depend on the relative tilt of magnetic field and on the SOC type: (a) when only Rashba SOC exists and the magnetic field is tilted in the direction of the superlattice (b) Dresselhaus SOC exists and the magnetic field is tilted in the direction perpendicular to the superlattice. Consequently, measurable properties of the modulated system become anisotropic in a tilted magnetic field when the field is conically rotated around the z axis, at a fixed polar angle, as we demonstrate by calculating the resistivity and the magnetization.

9.
J Phys Condens Matter ; 26(17): 172203, 2014 Apr 30.
Article in English | MEDLINE | ID: mdl-24722427

ABSTRACT

The stability of the Majorana modes in the presence of a repulsive interaction is studied in the standard semiconductor wire-metallic superconductor configuration. The effects of short-range Coulomb interaction, which is incorporated using a purely repulsive δ-function to model the strong screening effect due to the presence of the superconductor, are determined within a Hartree-Fock approximation of the effective Bogoliubov-De Gennes Hamiltonian that describes the low-energy physics of the wire. Through a numerical diagonalization procedure we obtain interaction corrections to the single particle eigenstates and calculate the extended topological phase diagram in terms of the chemical potential and the Zeeman energy. We find that, for a fixed Zeeman energy, the interaction shifts the phase boundaries to a higher chemical potential, whereas for a fixed chemical potential this shift can occur either at lower or higher Zeeman energies. These effects can be interpreted as a renormalization of the g-factor due to the interaction. The minimum Zeeman energy needed to realize Majorana fermions decreases with the increasing strength of the Coulomb repulsion. Furthermore, we find that in wires with multi-band occupancy this effect can be enhanced by increasing the chemical potential, i.e. by occupying higher energy bands.


Subject(s)
Electric Wiring , Models, Chemical , Quantum Theory , Semiconductors , Static Electricity , Computer Simulation , Equipment Failure Analysis
10.
Rom J Morphol Embryol ; 54(2): 365-9, 2013.
Article in English | MEDLINE | ID: mdl-23771083

ABSTRACT

Schizophrenia is recognized as a psychiatric disorder that causes the most pronounced disturbances of cognition and social integration. In the etiopathogenesis of the disease, genetic, neurobiological and vascular factors are involved. Functional integrity of the brain can be correlated with the integrity of the blood-brain barrier (BBB), and the dysfunction of this barrier is an indicator that suggests neurodevelopmental abnormalities, injuries of various etiologies and dysfunctions within the small vessels of the brain that disrupt the calcium homeostasis. Neuroimaging shows that in patients with poor evolution, cognitive dysfunction and therapeutic resistance, the presence of choroid plexus calcification associated with hippocampal, frontal, temporoparietal and cerebellar atrophies. Antipsychotics with high capacity to block D2 dopamine receptors (haloperidol model) can aggravate apoptotic mechanisms of the brain areas involved in cognition and disrupts the functional integrity of the BBB due to decreased of choroid plexus blood flow because of the narrowing of cerebral small vessels. Choroid plexus calcification may be a predictive indicator of poor evolution or of a neurodegenerative type.


Subject(s)
Blood-Brain Barrier/pathology , Calcinosis/pathology , Choroid Plexus/pathology , Schizophrenia/pathology , Adult , Atrophy/pathology , Calcinosis/diagnostic imaging , Choroid Plexus/diagnostic imaging , Female , Humans , Male , Middle Aged , Neuroimaging , Radiography , Schizophrenia/diagnostic imaging , Young Adult
11.
Rom J Morphol Embryol ; 53(2): 397-400, 2012.
Article in English | MEDLINE | ID: mdl-22732813

ABSTRACT

The neurobiological model of depressive disorder may be correlated with the animal model on rat, hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis, the increase of cortisol level being specific to the model of depression in women. The neurobiological model of depression in women presents vulnerabilities for some cerebral structures (hippocampus, frontal cortex, cerebral amygdala). A decrease of frontal cortex and hippocampus volumes are recognized in depressive disorder in women, depending on duration of disease and antidepressant therapy. Neurobiological vulnerability may be pronounced through cholinergic blockade. The purpose of the study was to highlight the cytoarchitectural changes in the frontal cortex and hippocampus by comparing two antidepressant substances: amitriptyline with a strong anticholinergic effect and trazodone, without anticholinergic effect. The superior neuroprotective qualities of trazodone for the frontal cortex, hippocampus and dentate gyrus are revealed. The particular neurobiological vulnerability of depression in women requires a differentiated therapeutic approach, avoiding the use of antidepressants with anticholinergic action.


Subject(s)
Antidepressive Agents, Tricyclic/pharmacology , Depressive Disorder/drug therapy , Neuroprotective Agents/pharmacology , Trazodone/pharmacology , Animals , Depressive Disorder/metabolism , Dexamethasone/pharmacology , Disease Models, Animal , Hydrocortisone/metabolism , Rats , Rats, Wistar
12.
J Phys Condens Matter ; 23(36): 365802, 2011 Sep 14.
Article in English | MEDLINE | ID: mdl-21857098

ABSTRACT

We develop a phenomenological theory for cross-plane transport in a semiconductor superlattice (SL) doped with nanostructures to improve the thermoelectric properties. The SL consists of an array of quantum wells equally spaced along a spatial direction separated by narrow barriers, such that, in the presence of inter-well tunneling, a miniband energy structure is established. The semi-metallic ErAs nanoparticles are embedded inside the quantum wells in the process of growth of the SL, as reported in several recent experiments. Their effect on thermoelectric transport is considered through an additional contribution to the electron scattering rate, that is correlated with a process of resonant tunneling through the nanoparticle-semiconductor interface modeled as a Schottky barrier. In a semi-classical approximation of the miniband conduction regime, we calculate the electric conductivity, the thermopower and the power factor as a function of the barrier height and demonstrate the presence of a filtering effect, whereby the Seebeck coefficient is enhanced by the additional scattering.

13.
Phys Rev Lett ; 97(17): 176802, 2006 Oct 27.
Article in English | MEDLINE | ID: mdl-17155492

ABSTRACT

We calculate the dephasing time tau(phi)(B) of an electron in a two-dimensional system with a Rashba spin-orbit interaction, spin-polarized by an arbitrarily large magnetic field parallel to the layer. tau(phi)(B) is estimated from the logarithmic corrections to the conductivity within a perturbative approach that assumes weak, isotropic disorder scattering. For any value of the magnetic field, the dephasing rate changes with respect to its unpolarized-state value by a universal function whose parameter is 2E(Z)/E(SOI) (E(Z) is the Zeeman energy, while E(SOI) is the spin-orbit interaction), confirming the experimental report published in Phys. Rev. Lett. 94, 186805 (2005). In the high-field limit, when 2E(Z) >> E(SOI), the dephasing rate saturates and reaches asymptotically to a value equal to half the spin-relaxation rate.

14.
Phys Rev Lett ; 93(10): 106601, 2004 Sep 03.
Article in English | MEDLINE | ID: mdl-15447432

ABSTRACT

We show that in order to calculate correctly the spin current carried by a quasiparticle in an electron liquid one must use an effective "spin mass" m(s) that is larger than both the band mass m(b), which determines the charge current, and the quasiparticle effective mass m(*), which determines the heat capacity. We present two independent estimates of the spin mass enhancement, m(s)/m(b), in two- and three-dimensional electron liquids, based on (i) previously calculated values of the Landau parameters and (ii) a recent theory of the dynamical local field factor in the spin channel. Both methods yield a significant spin mass enhancement, which is larger in two dimensions than in three.

15.
Gastroenterology ; 115(5): 1205-15, 1998 Nov.
Article in English | MEDLINE | ID: mdl-9797376

ABSTRACT

BACKGROUND & AIMS: The intestinal histology of murine semiallogeneic graft-versus-host (GVH) disease is characterized by lymphocytic infiltrates, crypt hyperplasia, and villous atrophy. Mechanisms of T cell-mediated changes of the mucosal architecture were investigated. METHODS: The rate of cellular apoptosis and proliferation, changes in the composition of extracellular matrix (ECM), and the role of OX40-OX40L interactions in the pathogenesis of villous atrophy and crypt hyperplasia were examined. RESULTS: The rate of apoptosis and the number of proliferating cells were significantly increased in GVH animals compared with control animals. In addition, expression of tenascin, an ECM component, was down-regulated in GVH animals. Inhibition of OX40-OX40L interactions in GVH animals by administration of an OX40-Ig fusion protein completely prevented the development of crypt hyperplasia and villous atrophy in GVH animals. Tenascin expression was up-regulated in OX40-Ig-treated mice compared with GVH animals, suggesting an important function of this ECM component in mucosal repair. CONCLUSIONS: The OX40-OX40L interaction is crucial in the pathogenesis of GVH, a T cell-mediated intestinal disease. The data suggest that the ECM component tenascin is probably relevant for the regeneration and maintenance of intestinal tissue architecture.


Subject(s)
Graft vs Host Disease/physiopathology , Intestines/physiopathology , Membrane Glycoproteins , Acute Disease , Animals , Apoptosis/physiology , Cell Division/physiology , Epithelial Cells/physiology , Extracellular Matrix Proteins/metabolism , Graft vs Host Disease/pathology , Immunoglobulins/physiology , Intestine, Small/pathology , Intestines/pathology , Jejunum/pathology , Jejunum/physiopathology , Kinetics , Mice , Mice, Inbred C57BL , Mice, Inbred DBA , OX40 Ligand , Receptors, OX40 , Receptors, Tumor Necrosis Factor/physiology , Regeneration/physiology , Tumor Necrosis Factor Receptor Superfamily, Member 7/immunology , Tumor Necrosis Factor Receptor Superfamily, Member 7/physiology , Tumor Necrosis Factors
16.
Met Based Drugs ; 5(5): 305-12, 1998.
Article in English | MEDLINE | ID: mdl-18475862

ABSTRACT

The synthesis of diaqua(1,10-phenanthroline-N,N')(thiosulfato-O,S)manganese(ll) [Mn(phen)(S(2)O(3))(H(2)O)(2)] was investigated. Its structure was determined by single crystal X-ray diffraction from 2418 reflections (I > 3 sigma(I)) to a final value of R = 0.047 and Rw = 0.054. Crystal data are as follows : space group P(2) (1); a = 10.356(3), b = 7.097(3), c = 20.316(2) A, beta = 94.29(2) degrees , V = 1489.1(8) , A(3), Z = 2. There are two independent title compounds in the asymetric unit. Each manganese atom has a distorted octahedral Mn(SO)N(2)O(2) geometry with the S and O atoms (from two neighbouring thiosulfate ligands) mutually trans, two N atoms from the 1,10-phenanthroline ligand and two water oxygen. The thiosulfate group behaves as a bridging ligand, connecting, through sulfur and oxygen, Mn atoms related by the binary b translation, thus forming infinite chains running parallel to this axis. Infrared and electronic spectra are reported.

17.
J Struct Biol ; 120(2): 146-57, 1997 Nov.
Article in English | MEDLINE | ID: mdl-9417979

ABSTRACT

New methods are described that should facilitate high-resolution (5-10 A) image reconstructions from low-dose, low-contrast electron micrographs of frozen-hydrated specimens and processing of large, digital images produced by new imaging devices and modern electron microscopes. Existing techniques for automatic selection of images of individual biological macromolecules from electron micrographs are inefficient or unreliable. We describe the Crosspoint method (CP), which produces good quality solutions with relatively small miss rates and few false hits, and an extension of this method along with a procedure for refining its solution. Two algorithms for processing large images, one based on image subsampling, the other on image decomposition, are described. A large image is first compressed (e.g., by subsampling) and the CP method is applied to the compressed image to produce an initial solution. The information gathered at this stage is used to cut the original image into subimages and then to refine the particle coordinates in each subimage. An interactive environment for experimenting with particle identification methods is described.


Subject(s)
Microscopy, Electron/methods , Viruses/ultrastructure , Algorithms , Bacteriophage phi X 174/ultrastructure , Image Processing, Computer-Assisted , Reoviridae/ultrastructure , Software
18.
Acta Crystallogr D Biol Crystallogr ; 51(Pt 5): 749-59, 1995 Sep 01.
Article in English | MEDLINE | ID: mdl-15299805

ABSTRACT

Electron-density averaging, fast Fourier synthesis and fast Fourier analysis programs have been adapted for parallel-computing systems. These have been linked to perform iterative phase improvement and extension utilizing non-crystallographic symmetry and solvent flattening. Various strategies for parallel algorithms have been tested on a variety of computers as a function of the number of computer nodes. Some experimental timing results are discussed.

19.
Sante Publique (Bucur) ; 32(2): 169-83, 1989.
Article in French | MEDLINE | ID: mdl-2781435

ABSTRACT

The exertion and risk factors in relation with the state of health, with the psychophysiological reactivity and with the adaptation and fatigue symptomatology were studied by means of complex psychological, psychophysiological, medical) methods in two professional groups that perform an activity implying important mental and sensorial components: monotasterers and correctors, from three polygraphic enterprises and two publishing houses, totalling 167 subjects (74 monotasterers and 93 correctors). The ergonomic work analysis demonstrated that the exertion and risk factors are conditioned both by the contents of work and by the working environment. The occupational exertion is more complex in monotasterers (mental, sensorial and physical) and predominantly sensorial (visual) in correctors. The work hazards are especially brought about by overstraining of the attention and of the visual analyser, with consequences both on the health of workers and on the quality of production. The investigation of the state of health, of the psychophysiological reactivity, as well as of the adaptation and fatigue symptomatology has detected maladjustment and fatigue phenomena, with impairments of the psychosomatic balance, more marked in monotasterers. The suggestions regarding improvement measures were directed both towards aspects of medico-psychological prophylaxis and elements of corrective ergonomics.


Subject(s)
Ergonomics , Health Status , Health , Neurotic Disorders/etiology , Occupational Diseases/etiology , Printing , Female , Humans , Male , Neurotic Disorders/diagnosis , Neurotic Disorders/epidemiology , Neurotic Disorders/psychology , Occupational Diseases/diagnosis , Occupational Diseases/epidemiology , Occupational Diseases/psychology , Psychophysiology , Risk Factors , Romania , Task Performance and Analysis
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