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1.
Interv Neuroradiol ; 26(2): 195-204, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31822162

ABSTRACT

BACKGROUND: Repeated mechanical thrombectomy for acute stroke treatment in individual patients has been proven feasible. However, less is known about the etiology of recurrent vessel occlusions after prior thrombectomy. We aimed to understand if the etiology of such recurrent events differs from the first stroke. METHODS: Retrospectively, we identified all patients at our center who received a repeated mechanical thrombectomy between 2007 and 2019. Clinical data were retrieved from medical records. Etiology of stroke was evaluated retrospectively, and angiographic studies were revisited. RESULTS: Twenty-three patients (1.5%) were identified. Median age was 68 years (IQR 56-77). Median NIHSS at first admission was 11 points (IQR 5-15). In nine cases (39.1%), the recurrent vessel occlusion was located exactly at the same position as the prior occlusion. Overall, five (21.7%) patients had a remarkable extracranial pathology as likely cause of stroke recurrence. In 16 patients (69.6%), the etiology of the first stroke and its recurrence was considered as likely being the same, mostly of cardioembolic or unknown origin. In the seven remaining patients (30.4%), the cause of stroke possibly differed from the first event, with five patients (21.7%) having a postinterventional intracranial intimal lesion as possible cause of stroke. CONCLUSION: Incidence of repeated thrombectomy was low. However, the high number of patients with known origin of stroke etiology raises the question how their monitoring may be optimized. The number of patients with remarkable extracranial pathologies or intracranial endothelial lesions supports current clinical practice to pay attention to final angiographic series.


Subject(s)
Arterial Occlusive Diseases/surgery , Cerebral Arterial Diseases/surgery , Thrombectomy/adverse effects , Adult , Aged , Female , Humans , Male , Middle Aged , Recurrence , Reoperation , Retrospective Studies , Stents , Stroke/complications , Stroke/etiology , Stroke/surgery , Treatment Outcome
2.
Clin Neurophysiol ; 125(3): 526-36, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24051073

ABSTRACT

OBJECTIVE: This article explores the feasibility of a novel repetitive navigated transcranial magnetic stimulation (rnTMS) system and compares language mapping results obtained by rnTMS in healthy volunteers and brain tumor patients. METHODS: Fifteen right-handed healthy volunteers and 50 right-handed consecutive patients with left-sided gliomas were examined with a picture-naming task combined with time-locked rnTMS (5-10 Hz and 80-120% resting motor threshold) applied over both hemispheres. Induced errors were classified into four psycholinguistic types and assigned to their respective cortical areas according to the coil position during stimulation. RESULTS: In healthy volunteers, language disturbances were almost exclusively induced in the left hemisphere. In patients errors were more frequent and induced at a comparative rate over both hemispheres. Predominantly dysarthric errors were induced in volunteers, whereas semantic errors were most frequent in the patient group. CONCLUSION: The right hemisphere's increased sensitivity to rnTMS suggests reorganization in language representation in brain tumor patients. SIGNIFICANCE: rnTMS is a novel technology for exploring cortical language representation. This study proves the feasibility and safety of rnTMS in patients with brain tumor.


Subject(s)
Brain Mapping/methods , Brain Neoplasms/pathology , Brain Neoplasms/physiopathology , Brain/physiology , Language , Neuronal Plasticity , Transcranial Magnetic Stimulation/methods , Adult , Aged , Brain Neoplasms/surgery , Craniotomy , Female , Healthy Volunteers , Humans , Language Tests , Magnetic Resonance Imaging , Male , Middle Aged , Preoperative Period , Psycholinguistics , Semantics
3.
Nanotechnology ; 19(6): 065706, 2008 Feb 13.
Article in English | MEDLINE | ID: mdl-21730712

ABSTRACT

There is increasing demand to functionalize meso- and nanoporous materials by coating and make the porous substrate biocompatible or environmentally friendly. However, coating on a meso-porous substrate poses great challenges, especially if the pore aspect ratio is high. We adopted the pulsed laser deposition (PLD) method to coat Ni(3)Al-based meso-porous membranes, which were fabricated from a single-crystal Ni-based superalloy by a unique selective phase dissolution technique. These membranes were about 250 µm thick and had channel-like pores (∼200 nm wide) with very high aspect ratio. Two different coating materials, i.e. diamond-like carbon (DLC) and titanium, were used to coat these membranes. High energy C or Ti ions, produced in the plasma plume by the PLD process, penetrated the channel-like pores and deposited coatings on the pore walls deep inside the membrane. The thickness and the quality of coatings on the pore walls were examined using the dual-beam system. The coating thickness, of the order of 50 nm, was adherent to the pore walls and was quite uniform at different depths. The carbon and the Ti deposition behaved quite similarly. The preliminary experiments showed that the PLD is an adequate method for coating fine open cavities of complex geometry. Simulations based on stopping and the range of ions in matter (SRIM) calculations helped in understanding the deposition processes on pore walls at great depths.

4.
Nanotechnology ; 16(10): 2176-87, 2005 Oct.
Article in English | MEDLINE | ID: mdl-20817992

ABSTRACT

A method which is able to produce different types of nano-structured materials, namely nano-particles, nano-structured surfaces and nano-porous membranes, from two-phase metallic alloys is reviewed. The new process first establishes nano-structures in the bulk alloy and then separates them by selective phase dissolution. Variation in processing makes it possible to produce different types of nano-structure even from the same alloy. The process can be applied to many different alloy systems. An overview is presented emphasizing the versatility of the process with examples of different nano-structure types that can be produced. Further, the new method is discussed in relation to similar processes (specifically, electrochemical processes) which have been used for nano-structure synthesis.

5.
Vertex ; 13(49): 212-6, 2002.
Article in Spanish | MEDLINE | ID: mdl-12404023

ABSTRACT

There would be a conceptual bridge between Psychoanalysis and the Neurosciences that would allow the translation of psychoanalytic concepts into neural mechanisms and vice-versa. Different Freudian postulates, such as that different types of anxiety would emerge from various cerebral interactions, the motivational regulatory functions of the impulse, the conscious emotion as the perception of something basically unconscious, the mechanism of repression in the traumatic memory, the existence of a system associated with the unconscious affective processes and regulated by the principle of pleasure - displeasure, the emotional representation as a basis of the more primitive cerebral structures, and the Oedipo complex, among others, are finding their biological ratification in different laboratory studies. This conceptual bridge would not only be a "Psychoanalysis-Neurobiological mechanisms" translator, but would also, through the integrated conceptualization of the psychoanalytical neurobiological aspects of emotion, generate relevant therapeutic models.


Subject(s)
Neurosciences , Psychoanalysis , Amygdala/metabolism , Anxiety/metabolism , Dopamine/metabolism , Hippocampus/metabolism , Humans
6.
Am J Ind Med ; 41(4): 259-68, 2002 Apr.
Article in English | MEDLINE | ID: mdl-11920969

ABSTRACT

BACKGROUND: Interstitial pulmonary fibrosis (IPF) is reported after long term, severe exposure to welding fumes in poorly ventilated workplaces. METHODS: Fifteen welders with IPF were examined--13 in our outpatient clinic--from 1990 to 1997. Occupational histories and examinations, lung function analyses, symptoms and clinical findings, histological analyses in 13 patients partly including SEM/EDX-analyses, chest X-rays, chest computed tomographies were conducted. RESULTS: Duration of work as welders was 28 years and the cumulative dose of welding fumes 221 mg/m(3) x years (median). Lung function studies found pattern of restriction or combined restriction-obstruction, lower diffusion capacity, and reduced blood oxygen tension at exercise. Histologically, patchy interstitial fibrosis was noted. Accumulations of particulate matter typically for welding fume were detected. EDX showed increase of iron load and close topographical relationship to welding fume particles embedded in areas of scattered fibrosis. CONCLUSION: While epidemiological data are limited, it is reasonable to conclude that a causal relationship exists between IPF in welders with long term exposure to high concentrations of welding fumes.


Subject(s)
Occupational Diseases/etiology , Pulmonary Fibrosis/etiology , Welding , Adult , Aged , Humans , Male , Middle Aged , Occupational Diseases/diagnosis , Occupational Exposure , Pulmonary Fibrosis/diagnosis , Respiratory Function Tests
7.
Vertex ; 13(49): 212-6, 2002 Sep-Nov.
Article in Spanish | BINACIS | ID: bin-39123

ABSTRACT

There would be a conceptual bridge between Psychoanalysis and the Neurosciences that would allow the translation of psychoanalytic concepts into neural mechanisms and vice-versa.Different Freudian postulates, such as that different types of anxiety would emerge from various cerebral interactions, the motivational regulatory functions of the impulse, the conscious emotion as the perception of something basically unconscious, the mechanism of repression in the traumatic memory, the existence of a system associated with the unconscious affective processes and regulated by the principle of pleasure - displeasure, the emotional representation as a basis of the more primitive cerebral structures, and the Oedipo complex, among others, are finding their biological ratification in different laboratory studies. This conceptual bridge would not only be a [quot ]Psychoanalysis-Neurobiological mechanisms[quot ] translator, but would also, through the integrated conceptualization of the psychoanalytical neurobiological aspects of emotion, generate relevant therapeutic models.

8.
Vertex rev. argent. psiquiatr ; 13(49): 212-6, 2002 Sep-Nov.
Article in Spanish | LILACS-Express | BINACIS | ID: biblio-1176666

ABSTRACT

There would be a conceptual bridge between Psychoanalysis and the Neurosciences that would allow the translation of psychoanalytic concepts into neural mechanisms and vice-versa.Different Freudian postulates, such as that different types of anxiety would emerge from various cerebral interactions, the motivational regulatory functions of the impulse, the conscious emotion as the perception of something basically unconscious, the mechanism of repression in the traumatic memory, the existence of a system associated with the unconscious affective processes and regulated by the principle of pleasure - displeasure, the emotional representation as a basis of the more primitive cerebral structures, and the Oedipo complex, among others, are finding their biological ratification in different laboratory studies. This conceptual bridge would not only be a [quot ]Psychoanalysis-Neurobiological mechanisms[quot ] translator, but would also, through the integrated conceptualization of the psychoanalytical neurobiological aspects of emotion, generate relevant therapeutic models.

9.
Int Orthop ; 24(1): 23-7, 2000.
Article in English | MEDLINE | ID: mdl-10774857

ABSTRACT

The purpose of this study was to evaluate the significance of positional relationships of the components on gait after total hip replacement (THR). Gait was analysed using multicomponent force platforms integrated into a treadmill, in conjunction with an optoelectric measuring system. 26 patients, after undergoing total hip replacement, were classified according to the vertical and horizontal positions of the centre of rotation, the vertical position of the femur and the functional leg length, and compared with a control group. Deterioration in parameters of gait was observed following cranialisation of the centre of rotation or of the femur, whereas neither medial movement of the centre of rotation nor leg lengthening by up to 1 cm had any effect. This study emphasises the importance of considering, at the time of preoperative planning, the effect of the position of the prosthesis on the functional parameters of gait.


Subject(s)
Arthroplasty, Replacement, Hip , Gait/physiology , Hip Prosthesis , Adult , Aged , Biomechanical Phenomena , Female , Hip/diagnostic imaging , Hip/physiology , Humans , Knee Joint/diagnostic imaging , Knee Joint/physiology , Leg/diagnostic imaging , Leg/physiology , Leg Length Inequality/etiology , Leg Length Inequality/physiopathology , Middle Aged , Osteoarthritis/surgery , Prospective Studies , Radiography , Rotation , Statistics, Nonparametric , Treatment Outcome , Video Recording
10.
Plant Physiol ; 113(1): 175-9, 1997 Jan.
Article in English | MEDLINE | ID: mdl-9008393

ABSTRACT

A full-length cDNA encoding phenylalanine ammonia-lyase (PAL) from Zea mays L. was isolated and the coding region was expressed in Escherichia coli as a C-terminal fusion to glutathione S-transferase. After purification by glutathione-Sepharose chromatography, the glutathione S-transferase moiety was cleaved off and the resulting PAL enzyme analyzed. In contrast to PAL from dicots, this maize PAL isozyme catalyzed the deamination of both L-phenylalanine (PAL activity) and L-tyrosine (tyrosine ammonia-lyase activity). These results provide unequivocal proof that PAL and tyrosine ammonia-lyase activities reside in the same polypeptide. In spite of large differences in the Michaelis constant and turnover number of the two activities, their catalytic efficiencies are very similar. Also, both activities have the same pH and temperature optima. These results imply that maize can produce p-coumaric acid from both phenylalanine and tyrosine.


Subject(s)
Ammonia-Lyases/metabolism , Phenylalanine Ammonia-Lyase/metabolism , Zea mays/enzymology , Amino Acid Sequence , Base Sequence , Escherichia coli/genetics , Molecular Sequence Data , Phenylalanine Ammonia-Lyase/genetics
11.
Plant Mol Biol ; 31(1): 69-76, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8704160

ABSTRACT

cDNA clones for all enzymes of the prechorismate pathway of higher plants have previously been cloned, with the exception of the second enzyme of the pathway, 3-dehydroquinate synthase. Here we describe the isolation of a cDNA encoding a 3-dehydroquinate synthase from tomato which was identified by complementing a 3-dehydroquinate synthase-deficient Escherichia coli strain with a tomato cDNA library. The deduced amino acid sequence contains a putative N-terminal plastid-specific transit peptide, and the sequence of the mature enzyme resembles those of the corresponding bacterial enzymes more than of the fungal enzymes. Sequence identity was even higher between the tomato and E. coli sequences than between the E. coli and other known bacterial sequences. The abundance of 3-dehydroquinate synthase transcripts differ in the organs of tomato plants analyzed. In cultured tomato cells, the abundance of 3-dehydroquinate synthase transcripts increased 9-fold within 4 to 5 h of elicitor treatment.


Subject(s)
Gene Expression Regulation, Enzymologic , Gene Expression Regulation, Plant , Lyases/genetics , Phosphorus-Oxygen Lyases , Solanum lycopersicum/genetics , Amino Acid Sequence , Base Sequence , Cloning, Molecular , DNA, Complementary , Solanum lycopersicum/enzymology , Solanum lycopersicum/microbiology , Molecular Sequence Data , Sequence Homology, Amino Acid
12.
Med Lav ; 86(5): 440-8, 1995.
Article in English | MEDLINE | ID: mdl-8684294

ABSTRACT

The Authors evaluate the risk of lung cancer and mesothelioma among asbestos workers in Germany. 3,988 workers (3,372 male and 616 female) were included in the study, which took into consideration the branch of the asbestos industry in which they had worked, the duration of their employment and also their smoking habits. At the end of the 12 year follow-up, 3,315 workers were alive and 673 dead. The analysis of cause of death showed an increased risk of dying from lung cancer and pleural and peritoneal mesothelioma, in men as well as in women. The risk was shown to be greatest among workers in the asbestos textile industry and among insulators. A probable multiplicative effect of asbestos exposure and smoking on lung cancer causation was noted.


Subject(s)
Asbestos/adverse effects , Lung Neoplasms/etiology , Mesothelioma/etiology , Occupational Exposure , Peritoneal Neoplasms/etiology , Pleural Neoplasms/etiology , Adult , Aged , Aged, 80 and over , Cohort Studies , Data Interpretation, Statistical , Female , Follow-Up Studies , Germany/epidemiology , Germany, West/epidemiology , Humans , Lung Neoplasms/epidemiology , Male , Mesothelioma/epidemiology , Middle Aged , Occupations , Peritoneal Neoplasms/epidemiology , Pleural Neoplasms/epidemiology , Registries , Risk Factors , Smoking/adverse effects , Time Factors
14.
J Occup Med ; 36(8): 889-93, 1994 Aug.
Article in English | MEDLINE | ID: mdl-7807270

ABSTRACT

A cohort study was conducted of 616 German female workers with a history of exposure to asbestos. Standardized proportionate mortality analysis was done except for mesothelioma, for which proportionate mortality was computed based on best evident cause of death. Mortality from lung cancer was increased three times over expected value. Death rates due to mesothelioma were 340 times higher than in the general population. Female mortality rates surpassed those observed in men twofold for lung cancer and fourfold for mesothelioma. In comparison with published data from international cohort studies, the observed mortality for mesothelioma in our female cohort appeared higher than that previously reported. German women with a history of asbestos exposure are considered a high-risk group for developing mesothelioma and lung cancer. They should be a target group for intervention strategies (eg, chemoprevention, smoking cessation, early cancer detection).


Subject(s)
Asbestos/adverse effects , Neoplasms/chemically induced , Neoplasms/mortality , Occupational Diseases/chemically induced , Occupational Diseases/mortality , Adult , Aged , Cause of Death , Female , Germany/epidemiology , Humans , Lung Neoplasms/chemically induced , Lung Neoplasms/mortality , Mesothelioma/chemically induced , Mesothelioma/mortality , Middle Aged , Occupational Exposure , Prospective Studies , Women's Health , Women, Working
16.
Article in English | MEDLINE | ID: mdl-2672716

ABSTRACT

The rational management of intracranial lesions should be based on the exact definition of the nature of the lesions and, when it is possible, on their spatial definition. Since External Radiotherapy (ERT) and cytostatic therapy are not free of undue effects, especially in children, such treatments should be used only when a "sure" diagnosis is obtained. The aim of this paper is to study the results allowed by the Talairach's stereotactic methodology in children. During the period January 1979-December 1986, 704 stereotactic procedures including serial biopsies, were performed at the S. Anne Hospital in Paris. One hundred forty-eight procedures (21%) concerned 134 children (78 M; 56 F) aged from 2 to 16 years. The interval between the occurrence of the first clinical symptoms and the stereotactic procedures varied between 1 and 180 months (m: 24 m). Fifty-two (40%) had previous therapeutic procedures without precise diagnosis. The lesions were hemispheric in 46 (34%) and deep seated in 88 (66%). The serial stereotactic biopsies proved the existence of a non-tumoural lesion in 20 children (14.9%): (cryptic vascular malformation: 5, cortical dysplasia: 3, haematoma: 3, ischaemia: 1, granuloma: 1, degenerative pathology: 2, cicatrix: 2, post-ERT alterations: 1, arachnoidal cyst: 2). Four were in the brain stem. In 3 patients (2%), a precise diagnosis was not obtained. The CT scan characteristics of the 20 non-tumoural lesions did not permit to establish a precise differential diagnosis. The therapeutic management was adapted to the diagnosis, avoiding potentially dangerous procedures in the 20 non-tumoural lesions.


Subject(s)
Brain Diseases/pathology , Brain Neoplasms/pathology , Stereotaxic Techniques , Adolescent , Biopsy, Needle , Brain/pathology , Child , Child, Preschool , Diagnosis, Differential , Female , Humans , Male
17.
Article in French | MEDLINE | ID: mdl-3296042

ABSTRACT

This study concerns 180 patients (132 M; 48 F) (age: 2 to 69 years; m: 33 years) who underwent stereotactic procedures according to the methodology of Talairach and Szikla. Such procedures (stereotactic and stereoscopic angiography in all cases, and ventriculography in 81%) should permit a correct spatial definition of intracranial lesions. The informations provided by the angiography (normal in 7%) and by the ventriculography (normal in 11%) are complementary to those yielded by the TDM and permit an easier and safe stereotactic approach to the lesions. In 43% of patients the lesions were deep-seated (basal ganglia: 24; sellar region: 19; thalamo-peduncular: 13; brain stem: 6, etc.). The histological examination showed: low-grade gliomas in 43%; glioblastomas in 21%; non tumoral lesions in 17%. A precise diagnosis couldn't be obtained in 3.8%. The data provided by the stereo-EEG (in 11 patients suffering also of severe drug-resistant partial epilepsy) did not permit, alone, an histological diagnosis, excepted when electrodes explored a solid tumor. Two patients had a neurological impairment, and two died (one for extracerebral reasons). The authors consider that the TDM data and the informations given by the stereotactic procedures are complementary for obtaining valuable informations on the spatial organization of intracranial lesions and choosing the best treatment.


Subject(s)
Brain Diseases/diagnostic imaging , Stereotaxic Techniques , Tomography, X-Ray Computed , Adolescent , Adult , Aged , Biopsy/methods , Brain Diseases/pathology , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/pathology , Cerebral Angiography , Cerebral Ventriculography , Child , Child, Preschool , Electroencephalography/methods , Female , Humans , Male , Middle Aged
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