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1.
Acta Neurol Scand ; 137(1): 91-98, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28869277

RESUMEN

OBJECTIVES: Cognitive decline is common in Parkinson's disease (PD), but the underlying mechanisms for this complication are incompletely understood. Genotypes affecting dopamine transmission may be of importance. This study investigates whether genotypes associated with reduced prefrontal dopaminergic tone and/or reduced dopamine D2-receptor availability (Catechol-O-methyltransferase [COMT] Val158 Met genotype and DRD2 C957 T genotype) affect the development of cognitive deficits in PD. MATERIALS AND METHODS: One hundred and 34 patients with idiopathic PD, participating in a regional, population-based study of incident parkinsonism, underwent genotyping. After extensive baseline investigations (including imaging and biomarker analyses), the patients were followed prospectively during 6-10 years with neuropsychological evaluations, covering six cognitive domains. Cognitive decline (defined as the incidence of either Parkinson's disease mild cognitive impairment [PD-MCI] or dementia [PDD], diagnosed according to published criteria and blinded to genotype) was studied as the primary outcome. RESULTS: Both genotypes affected cognition, as shown by Cox proportional hazards models. While the COMT 158 Val/Val genotype conferred an increased risk of mild cognitive impairment in patients with normal cognition at baseline (hazard ratio: 2.13, P = .023), the DRD2 957 T/T genotype conferred an overall increased risk of PD dementia (hazard ratio: 3.22, P < .001). The poorer cognitive performance in DRD2 957 T/T carriers with PD occurred mainly in episodic memory and attention. CONCLUSIONS: The results favor the hypothesis that dopamine deficiency in PD not only relate to mild cognitive deficits in frontostriatal functions, but also to a decline in memory and attention. This could indicate that dopamine deficiency impairs a wide network of brain areas.


Asunto(s)
Catecol O-Metiltransferasa/genética , Disfunción Cognitiva/genética , Enfermedad de Parkinson/genética , Receptores de Dopamina D2/genética , Anciano , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Enfermedad de Parkinson/complicaciones , Polimorfismo de Nucleótido Simple
2.
Ann Dermatol Venereol ; 142(5): 332-9, 2015 May.
Artículo en Francés | MEDLINE | ID: mdl-25846467

RESUMEN

BACKGROUND: Acute ischemia of the upper limbs is rare in comparison with ischemia of the lower limbs. The origins of this condition are varied. GOALS: We retrospectively analyzed cases of acute finger ischemia (Raynaud's phenomena was excluded) in a dermatology department between 2008 and 2013 in order to evaluate the etiology and management of this phenomenon. RESULTS: Thirteen cases of finger ischemia were reported. The mean age was 54 years. Active smoking was noted in 11 cases. Ischemia was acute in 9 cases and subacute in 4 cases. The location was unilateral in 10 cases and bilateral in 2. Etiologies were: dysplasia of the palmar arch, antiphospholipid antibody syndrome, frostbite, distal arteritis linked to smoking, paraneoplastic arteritis, Buerger's disease, polyarteritis nodosa, stenosis of the subclavian artery, and 3 cases of embolic origin (ulnar, cardiac, and paraneoplastic aneurysm). In the acute phase, antiplatelets were given in 6 cases, anticoagulants in 10 cases and ilomedin in 6 cases. Sympathectomy was performed in 1 case and amputation in 2 cases. DISCUSSION: This study illustrates the diversity of etiologies of finger ischemia. The etiological test battery should be broad and include immunological and thrombophilia tests, arterial and cardiac investigations, cervical radiography and CT scan (screening for cancer). Close collaboration between dermatologists, hematologists, vascular surgeons and radiologists is essential for the management of these patients.


Asunto(s)
Dedos/irrigación sanguínea , Isquemia/etiología , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Amputación Quirúrgica , Síndrome Antifosfolípido , Arteritis/complicaciones , Femenino , Dedos/cirugía , Congelación de Extremidades/complicaciones , Humanos , Isquemia/terapia , Masculino , Persona de Mediana Edad , Síndromes Paraneoplásicos/complicaciones , Inhibidores de Agregación Plaquetaria/uso terapéutico , Poliarteritis Nudosa/complicaciones , Estudios Retrospectivos , Fumar/efectos adversos , Síndrome del Robo de la Subclavia/complicaciones , Simpatectomía , Tromboangitis Obliterante/complicaciones
3.
Acta Neurol Scand ; 130(1): 27-33, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24341730

RESUMEN

OBJECTIVES: To investigate the effect of caudal zona incerta-deep brain stimulation (cZi-DBS) on word-level speech intelligibility in patients with Parkinson's disease, under both an optimal listening condition and a simulated more naturalistic listening condition. MATERIALS AND METHODS: Spoken single words were extracted from read samples collected from 10 bilaterally implanted patients with PD pre- and post-cZi-DBS. Intelligibility was assessed through a transcription task performed by 32 naive listeners under two listening conditions: (i) with low-amplitude conversational speech added as background and (ii) with no added background noise. The listeners' responses were scored in terms of agreement with the intended words. RESULTS: Post-operatively, the total intelligibility score was significantly lower when cZi stimulation was switched on compared with off, for both listening conditions (with and without added background noise). Intelligibility was also significantly lower on stimulation compared with preoperative recordings, but only when assessed in the listening condition without background noise. The listening condition with added background noise resulted in significantly lower intelligibility scores compared with the no added noise condition for all stimulation conditions. CONCLUSIONS: The results of this study indicate that cZi-DBS in patients with PD can be detrimental to word-level speech intelligibility.


Asunto(s)
Estimulación Encefálica Profunda/métodos , Enfermedad de Parkinson/terapia , Inteligibilidad del Habla , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/complicaciones , Trastornos del Habla/etiología , Trastornos del Habla/terapia , Zona Incerta/fisiología
4.
Ann Dermatol Venereol ; 141(11): 682-4, 2014 Nov.
Artículo en Francés | MEDLINE | ID: mdl-25442472

RESUMEN

BACKGROUND: Herein we report a case of phlegmasia cerulea dolens, a form of venous thrombosis complicated by arterial ischaemia. PATIENTS AND METHODS: A 69-year-old man presented a bilateral trophic condition of the lower limbs that had appeared 3 weeks earlier. The patient had a history of metastatic urothelial bladder carcinoma and arteritis. Clinical examination revealed right leg ulcers with massive bilateral oedema of the lower limbs, cyanosis and local ischaemia. Doppler ultrasound revealed bilateral and proximal deep vein thrombosis (sural and superficial femoral veins of the right leg; sural and iliac veins of the left leg) without any distal arterial flow. We concluded on a diagnosis of bilateral phlegmasia cerulea dolens. DISCUSSION: Phlegmasia cerulea dolens is a particular type of deep venous thrombosis in which a proximal venous thrombus is combined with arterial ischaemic signs due to brutal and massive oedema and slowing down of arterial flow. In most cases, the lower limbs are involved, with malignancy being the most common cause. It should be suspected in the presence of the classical triad of "pain, oedema and cyanosis", with confirmation by Doppler ultrasound. There is no general consensus regarding standard management. Traditionally, systemic anticoagulation has been the mainstay of treatment for this condition. Endovascular surgery may be a possibility in some cases. Prompt diagnosis and rapid treatment initiation are paramount in order to improve the prognosis of this severe condition with ominous prospects.


Asunto(s)
Arteritis/diagnóstico por imagen , Isquemia/diagnóstico por imagen , Pierna/irrigación sanguínea , Tromboflebitis/diagnóstico por imagen , Trombosis de la Vena/diagnóstico por imagen , Anciano , Carcinoma/secundario , Carcinoma/cirugía , Diagnóstico Diferencial , Edema/diagnóstico , Vena Femoral/diagnóstico por imagen , Humanos , Vena Ilíaca/diagnóstico por imagen , Úlcera de la Pierna/diagnóstico , Metástasis Linfática/patología , Masculino , Ultrasonografía Doppler/métodos , Neoplasias de la Vejiga Urinaria/cirugía , Urotelio/patología
5.
J Small Anim Pract ; 65(6): 402-408, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38566458

RESUMEN

OBJECTIVES: Myoclonic seizures are considered a type of generalised seizure characterised by brief, jerking movements of the body. The aim of this study is to describe cases of suspected canine myoclonic seizure of idiopathic aetiology and to discuss the successful use of the anticonvulsant levetiracetam as treatment in each of these cases. MATERIALS AND METHODS: Dogs with epileptic myoclonus suspected to be idiopathic in aetiology were considered for inclusion. Medical records were reviewed for physical and neurologic examination findings, clinicopathologic results, and diagnostic imaging results. All included dogs were treated with levetiracetam, and their response was reported. RESULTS: Five dogs were included, all of which had suspected myoclonic seizures either observed in-person or on video recording by a board-certified veterinary neurologist. The duration of myoclonic seizures preceding treatment ranged from one day to one year. One dog also experienced a generalised tonic-clonic seizure. All dogs were treated with levetiracetam. Two dogs experienced long-term myoclonic seizure freedom (duration seizure-free of at least 1 year), and two dogs experienced marked decreased myoclonic seizure frequency. One dog experienced immediate abatement of myoclonic seizures, although levetiracetam was only utilised for 1 month following onset of myoclonic seizures in this patient. CLINICAL SIGNIFICANCE: Myoclonic seizures can be idiopathic in aetiology. Levetiracetam can be used effectively to rapidly stop myoclonic seizures and to decrease the frequency of myoclonic seizures.


Asunto(s)
Anticonvulsivantes , Enfermedades de los Perros , Epilepsias Mioclónicas , Levetiracetam , Perros , Levetiracetam/uso terapéutico , Animales , Anticonvulsivantes/uso terapéutico , Enfermedades de los Perros/tratamiento farmacológico , Femenino , Masculino , Epilepsias Mioclónicas/veterinaria , Epilepsias Mioclónicas/tratamiento farmacológico , Resultado del Tratamiento
6.
Acta Neurol Scand ; 127(5): 329-36, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23116242

RESUMEN

OBJECTIVE: In patients with Parkinson's disease (PD), deep brain stimulation of the subthalamic nucleus (STN DBS) is well recognized in improving limb function, but the outcome on swallowing function has rarely been studied. The aim of this work was to evaluate the effect of STN DBS on pharyngeal swallowing function in patients with PD using self-estimation and fiberoptic endoscopic evaluation of swallowing. METHODS: Eleven patients (aged 41-72, median 61 years) were evaluated preoperatively and at 6 and 12 months after STN DBS surgery. All patients were evaluated with self-estimation on a visual analogue scale, and eight of them with a fiberoptic endoscopic examination with a predefined swallowing protocol including Rosenbek's Penetration-Aspiration Scale, Secretion Severity Scale, preswallow spillage, pharyngeal residue, and pharyngeal clearance. RESULTS: The self-assessments of swallowing function revealed a subjective improvement with STN DBS stimulation, whereas the data from the swallowing protocol did not show any significant effect of the STN DBS treatment itself. The prevalence of aspiration was not affected by the surgery. CONCLUSIONS: The results show that swallowing function was not negatively affected by STN DBS and the risk of aspiration did not increase. Self-estimation of swallowing function showed a subjective improvement due to stimulation.


Asunto(s)
Estimulación Encefálica Profunda , Deglución/fisiología , Enfermedad de Parkinson/terapia , Adulto , Anciano , Antiparkinsonianos/uso terapéutico , Terapia Combinada , Estimulación Encefálica Profunda/efectos adversos , Autoevaluación Diagnóstica , Femenino , Humanos , Levodopa/uso terapéutico , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/fisiopatología , Neumonía por Aspiración/etiología , Neumonía por Aspiración/prevención & control , Índice de Severidad de la Enfermedad , Núcleo Subtalámico/fisiopatología
7.
Acta Neurol Scand ; 126(5): 350-6, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22384826

RESUMEN

OBJECTIVE: The purpose of the present study was to examine whether there was a negative effect of caudal Zona Incerta deep brain stimulation (cZI DBS) on pharyngeal swallowing function in Parkinson's patients (PD). There are no former reports including swallowing and cZI DBS. METHODS: Eight patients (aged 49-71 years; median 62) were evaluated pre- and post-operatively, at 6 and 12 months after DBS surgery. Evaluation tools were fiberoptic endoscopic evaluation of swallowing examinations and patients' self-assessments of their swallowing function including a visual analog scale and quality-of-life-related questions. The swallowing protocol included Rosenbek's Penetration-Aspiration Scale, Secretion Severity Scale and parameters for preswallow spillage, pharyngeal residue, and pharyngeal clearance. RESULTS: There was no clear-cut effect of neurostimulation post-operatively at 6 and 12 months on any of the swallowing parameters except for the preswallow spillage that was slightly worsened in the stimulation on condition 12 months post-operatively. The answers to the self assessment questions did not vary significantly. CONCLUSIONS: The effect of the stimulation on the swallowing function varied among individuals, but the overall outcome was that cZI DBS did not seem to have a negative influence on swallowing function in the eight patients studied.


Asunto(s)
Deglución/fisiología , Enfermedad de Parkinson/fisiopatología , Enfermedad de Parkinson/terapia , Subtálamo/fisiopatología , Anciano , Estimulación Encefálica Profunda , Femenino , Humanos , Masculino , Persona de Mediana Edad
8.
Acta Neurol Scand ; 126(4): 248-55, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22211900

RESUMEN

OBJECTIVES: The differential diagnosis of patients with idiopathic parkinsonism is difficult, especially early in the course of the disease. External anal sphincter electromyography (EAS-EMG) has been reported to be of value in the differential diagnosis between Parkinson's disease (PD) and multiple system atrophy (MSA). Patients with MSA are reported to have pathological EAS-EMG and patients with PD are reported to have significantly less pathological EAS-EMG results. Comparisons between patients with parkinsonian disorders have usually been made many years into the disease, and thus it is largely unknown if the results of EAS-EMG can be used to distinguish the different diagnoses in the early phase of the disease. MATERIALS AND METHODS: We investigated 148 newly diagnosed patients with idiopathic parkinsonism from a population-based incidence cohort (100 definite PD, 21 probable PD, 16 MSA, 11 progressive supranuclear palsy, and 40 controls) with EAS-EMG within 3 months of their first visit and, in the majority of patients, before start of treatment with dopaminergic drugs. The clinical diagnoses were made using established clinical diagnostic criteria after a median follow-up of 3 years. RESULTS: All patient groups had more pathological EAS-EMG results than controls. No EAS-EMG differences were found between the patient groups, especially not between PD and MSA. CONCLUSIONS: External anal sphincter electromyography examination cannot separate the different parkinsonian subgroups from each other in early course of the diseases.


Asunto(s)
Canal Anal/patología , Electromiografía , Músculo Liso/fisiopatología , Trastornos Parkinsonianos/patología , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Atrofia de Múltiples Sistemas/patología , Trastornos Parkinsonianos/diagnóstico , Trastornos Parkinsonianos/diagnóstico por imagen , Cintigrafía , Estadística como Asunto , Parálisis Supranuclear Progresiva/patología
9.
Acta Neurol Scand ; 126(6): e29-33, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22690905

RESUMEN

BACKGROUND: This interim 12-month analysis is a part of an open-label, observational, prospective study on health outcomes and cost impact of levodopa/carbidopa intestinal gel (LCIG, Duodopa) in Parkinson disease (PD). The specific aim was to investigate clinical and health-related quality of life (HRQoL) effects in routine care. METHODS: Unified PD rating scale (UPDRS) was the primary efficacy measurement. PD QoL questionnaire 39 (PDQ-39) assessed HRQoL. Subjects were assessed at baseline, ≥3 months after surgery, and then every 3 months. RESULTS: Twenty-seven treatment-naïve subjects when started with LCIG showed a decrease in UPDRS score that was statistically significant throughout the year: UPDRS total score (mean ± SD), baseline = 52.1 ± 16.1, N = 27, month 0 (first visit; at least 3 months after permanent LCIG) = 43.1 ± 16.7, N = 27, P = 0.003; month 12 = 42.5 ± 22.6, n = 25, P = 0.017. PDQ-39 results also showed a tendency for improvement: PDQ-39 (mean ± SD), baseline = 33.6 ± 10.8, N = 27, month 0 = 27.1 ± 11.8, N = 27, P = 0.001; 12 months = 28.8 ± 12.8, n = 23, P = 0.126. CONCLUSIONS: LCIG provides functional improvement beginning at first visit that is sustained for 12 months.


Asunto(s)
Antiparkinsonianos/administración & dosificación , Carbidopa/administración & dosificación , Levodopa/administración & dosificación , Enfermedad de Parkinson/tratamiento farmacológico , Vías de Administración de Medicamentos , Combinación de Medicamentos , Femenino , Humanos , Infusiones Parenterales , Masculino , Persona de Mediana Edad , Calidad de Vida , Resultado del Tratamiento
10.
J Eur Acad Dermatol Venereol ; 24(4): 403-9, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19778361

RESUMEN

BACKGROUND AND OBJECTIVES: Patients report well-being as they are treated with phototherapy. We investigated hormone parameters and psychological well-being after phototherapy in a placebo-controlled study. METHODS: A total of 77 patients with dermatological conditions and 22 healthy volunteers were divided into four groups. The patients received phototherapy either on the whole body or only on hands and/or feet. The volunteers were given either whole-body phototherapy or placebo light. Serum or plasma samples were analysed for cortisol, calcium, magnesium, phosphate, TSH, T(4), T(3) and 25-hydroxyvitamin D, and urine samples for cortisol. Patients and volunteers answered a questionnaire before and 6 weeks after phototherapy/placebo light. Psychiatric ratings were performed according to the Comprehensive Psychopathological Self-rating Scale for Affective Syndromes, a self-report version of which has been transformed to correspond to the Montgomery-Asberg Depression Rating Scale (MADRS). RESULTS: In the patients who received whole-body irradiation, we observed a significant improvement in both MADRS score and cognitive-symptom score after the completion of phototherapy. We also observed a significantly higher level of 25-hydroxyvitamin D after phototherapy, but no difference in the other hormone parameters. CONCLUSION: Whole-body phototherapy of patients with dermatological conditions results in improved well-being and significantly higher levels of 25-hydroxyvitamin D in serum.


Asunto(s)
Hormonas/sangre , Enfermedades de la Piel/psicología , Enfermedades de la Piel/radioterapia , Terapia Ultravioleta/métodos , Terapia Ultravioleta/psicología , Adulto , Afecto , Pie , Mano , Humanos , Hidrocortisona/sangre , Persona de Mediana Edad , Terapia PUVA/métodos , Terapia PUVA/psicología , Placebos , Pruebas Psicológicas , Encuestas y Cuestionarios , Tiroxina/sangre , Triyodotironina/sangre , Vitamina D/análogos & derivados , Vitamina D/sangre , Irradiación Corporal Total/métodos , Irradiación Corporal Total/psicología
11.
J Cell Biol ; 83(2 Pt 1): 371-82, 1979 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-500785

RESUMEN

We have studied fluid secretion by the contractile vacuole apparatuss of the trypanosomatid flagellate Leptomonas collosoma with thin sections and freeze-fracture replicas of cells stabilized by ultrarapid freezing without prior fixation or cryoprotection. The ultrarapid freezing has revealed membrane specializations related to fluid segregation and transport as well as membrane rearrangements which may accompany water expulsion at systole. This osmoregulatory apparatu consists of the spongiome, the contractile vacuole, and the fluid discharge site. The coated tubules of the spongiome converge on the contractile vacuole from all directions. These 60- to 70-nm tubules contain characteristic double rows of 11-nm intramembrane particles in a helical configuration which fracture predominantly with the E face. Short double rows of similar particles are also frequently found on both faces of the contractile vacuole itself, in addition to many smaller particles on the P face. The spongiome tubules fuse with the vacuole during the filling stage of each cycle and then detach before secretion. The contractile vacuole membrane is permanently attached to the plasma membrane of the flagellar pocket by a dense adhesion plaque. In some ultrarapidly frozen cells, 20- to 40-nm perforations can be visualized within the plaque and the adjacent membranes during the presumptive time of discharge. The formation of the plaque perforations and the membrane channels occurs without fusion of the vacuole and the plasma membrane and does not require extracellular calcium. On the basis of our results, we have developed a model for water secretion which suggests that the adhesion plaque may induce pore formation in the adjoining lipid bilayers, thereby allowing bulk expulsion of the fluid.


Asunto(s)
Eucariontes/ultraestructura , Modelos Biológicos , Animales , Calcio/farmacología , Membrana Celular/ultraestructura , Eucariontes/fisiología , Técnica de Fractura por Congelación , Membranas/ultraestructura , Vacuolas/fisiología , Vacuolas/ultraestructura
12.
Eur J Neurol ; 16(12): 1278-84, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19538208

RESUMEN

BACKGROUND AND PURPOSE: The study aims to describe the frequency, pattern and determinants of cognitive function in patients with newly diagnosed Parkinson's disease (PD); to compare patients with impaired cognition to patients with intact cognition; and to compare to matched healthy controls. METHODS: Patients were identified in a longitudinal population based study of idiopathic non-drug induced parkinsonism. Eighty-eight newly diagnosed patients with PD and no dementia were included during a four year period. The patients and 30 age- and sex-matched healthy control subjects underwent a comprehensive neuropsychological assessment. RESULTS: Patients performed significantly worse than healthy controls in a majority of neuropsychological tests. Test results in attention, psychomotor function, episodic memory (free recall), executive function and category fluency were significantly lower in the patient group. Comparison with normative data revealed that 30% of the patients had deficits in > or =1 cognitive domain (episodic memory, executive function and verbal function). Seventy per cent of the patients had normal performance. Unified Parkinson's Disease Rating Scale (UPDRS) III sub scores; speech, facial expression, rigidity and bradykinesia were significantly higher, and disease duration shorter amongst the cognitively impaired than amongst the cognitively intact patients. Tremor showed no difference. Education level was an independent predictor of dysfunction in patients with > or =2 cognitive domains affected. CONCLUSION: Cognitive dysfunction is common in untreated patients in early PD, affecting attention, psychomotor function, episodic memory, executive function and category fluency. Education level was an independent predictor of severe cognitive dysfunction.


Asunto(s)
Trastornos del Conocimiento/complicaciones , Trastornos del Conocimiento/epidemiología , Enfermedad de Parkinson/complicaciones , Anciano , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas
13.
Trends Genet ; 17(6): 306-8, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11377780

RESUMEN

A consortium of laboratories undertook a pilot sequencing project to gain insight into the genome of Paramecium. Plasmid-end sequencing of DNA fragments from the somatic nucleus together with similarity searches identified 722 potential protein-coding genes. High gene density and uniform small intron size make random sequencing of somatic chromosomes a cost-effective strategy for gene discovery in this organism.


Asunto(s)
Genoma de Protozoos , Paramecium/genética , Animales , Humanos , Paramecium/clasificación , Filogenia , Proyectos Piloto , Proteínas Protozoarias/genética
14.
Sci Rep ; 7: 40604, 2017 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-28106102

RESUMEN

Spin filter superconducting S/I/N tunnel junctions (NbN/GdN/TiN) show a robust and pronounced Zero Bias Conductance Peak (ZBCP) at low temperatures, the magnitude of which is several times the normal state conductance of the junction. Such a conductance anomaly is representative of unconventional superconductivity and is interpreted as a direct signature of an odd frequency superconducting order.

15.
Nat Commun ; 8: 14024, 2017 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-28102222

RESUMEN

Electron pairing in the vast majority of superconductors follows the Bardeen-Cooper-Schrieffer theory of superconductivity, which describes the condensation of electrons into pairs with antiparallel spins in a singlet state with an s-wave symmetry. Unconventional superconductivity was predicted in single-layer graphene (SLG), with the electrons pairing with a p-wave or chiral d-wave symmetry, depending on the position of the Fermi energy with respect to the Dirac point. By placing SLG on an electron-doped (non-chiral) d-wave superconductor and performing local scanning tunnelling microscopy and spectroscopy, here we show evidence for a p-wave triggered superconducting density of states in SLG. The realization of unconventional superconductivity in SLG offers an exciting new route for the development of p-wave superconductivity using two-dimensional materials with transition temperatures above 4.2 K.

16.
J Natl Cancer Inst ; 80(8): 576-80, 1988 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-3259635

RESUMEN

Successful cytogenetic studies were performed on 69 biopsies from 64 patients with non-Hodgkin's lymphoma bearing a t(14;18)(q32;q21) translocation. This translocation appears to be a primary abnormality associated with the development of certain B-cell non-Hodgkin's lymphomas. We correlated the occurrence of secondary abnormalities, in addition to the t(14;18)(q32;q21), with histologic subtype to test the hypothesis that secondary abnormalities correlate with more aggressive histologic appearance. A large number of secondary abnormalities were identified, the most frequent being additional copies of chromosomes 7 (30%), 12 (22%), 18 (22%), 20 (16%), or 21 (14%), deletion of a portion of the long arm of chromosome 6 (17%), and either an additional chromosome 17 or an isochromosome for the long arm of chromosome 17 (13%). An extra chromosome 7 was highly associated with a diffuse histologic pattern; it was present in 52% of patients with a diffuse pattern and in only 15% of those with a follicular pattern (P = .002). A weaker association with a diffuse growth pattern was found for the addition of chromosome 17 or an i(17q); it was found in 24% of patients with a diffuse pattern and only 5% of those with a follicular pattern (P = .05). No other significant correlations between secondary chromosome abnormalities and histologic subtype were identified. Although the explanation for this association is not clear, it appears that patients with B-cell non-Hodgkin's lymphomas bearing the t(14;18)(q32;q21) translocation which also have an additional chromosome 7 are likely to exhibit a diffuse growth pattern.


Asunto(s)
Aberraciones Cromosómicas , Linfoma no Hodgkin/genética , Translocación Genética , Linfocitos B/ultraestructura , Humanos , Cariotipificación , Linfoma no Hodgkin/patología , Persona de Mediana Edad , Fenotipo
17.
Acta Chir Belg ; 106(4): 447-9, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17017707

RESUMEN

Infected abdominal aortic aneurysms are uncommon but not rare (1-3% of all abdominal aortic aneurysms). This life-threatening disease can lead to rapid uncontrolled sepsis and/or aortic rupture. We report one case that underlines two notions. Firstly computed tomography is effective to detect early stages of the pathology providing complete depiction of the anatomical abnormalities. Secondly infected aortic aneurysm can be successfully treated by antibiotherapy and in situ replacement with cryopreserved arterial homograft.


Asunto(s)
Aneurisma Infectado/cirugía , Aorta/trasplante , Aneurisma de la Aorta Abdominal/microbiología , Criopreservación , Infecciones Neumocócicas/cirugía , Combinación Amoxicilina-Clavulanato de Potasio/uso terapéutico , Aneurisma Infectado/tratamiento farmacológico , Antibacterianos/uso terapéutico , Aneurisma de la Aorta Abdominal/tratamiento farmacológico , Aneurisma de la Aorta Abdominal/cirugía , Aortitis/tratamiento farmacológico , Aortitis/microbiología , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Infecciones Neumocócicas/tratamiento farmacológico , Trasplante Homólogo
18.
J Clin Oncol ; 7(12): 1783-90, 1989 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2585020

RESUMEN

We performed a prospective study of the clinical significance of immunophenotype in 110 patients with aggressive non-Hodgkin's lymphoma (NHL) treated by oncologists in the Nebraska Lymphoma Study Group between October 1982 and May 1986. All patients were immunophenotyped from biopsies performed before therapy was administered. The patients were treated with a uniform protocol of radiotherapy for minimal nonbulky, stage I or II disease (seven patients) or a single, six-drug chemotherapy regimen cyclophosphamide, doxorubicin, procarbazine, bleomycin, vincristine, and prednisone (CAP-BOP) in patients with more extensive disease (103 patients). Ninety-one patients (83%) had B-cell lymphoma and 19 patients (17%) had T-cell lymphoma. The histologic diagnosis of diffuse mixed-cell lymphoma was significantly associated with T-cell immunophenotype (45% v 5%; P less than .001), and the diagnosis of diffuse large-cell lymphoma was significantly associated with B-cell immunophenotype (40% v 5%; P = .006). However, no significant difference in frequency of prognostic variables such as age, stage, systemic symptoms, tumor bulk, serum lactic dehydrogenase, or performance status was found between the B-cell and T-cell groups. Patients with B-cell NHL had a slightly higher complete remission rate (74% v 53%; P = NS), similar durability of complete remission (75% v 70% at 3 years; P = NS), and a slightly but not significantly better overall survival (50% v 41% at 3 years; P = NS). The slight advantage in response rate and survival for B-cell patients was related to a very poor outcome for patients with stage IV T-cell NHL. For patients with stage I to III disease, neither the complete remission rate (B-cell, 82% v T-cell, 91%; P = NS) nor overall survival (3-year survival for B cell, 58% v T cell, 73%; P = NS) were significantly different. However, with stage IV disease B-cell patients fared far better than those with T-cell NHL for both complete remission rate (67% v 0%; P = .002) and overall survival (3-year survival, 44% v 0%; P = .002). Immunophenotyping intermediate- and high-grade NHL allowed identification of a subgroup of patients who had a very poor prognosis with this treatment approach and for whom alternate therapy might be considered.


Asunto(s)
Antígenos de Neoplasias/análisis , Linfoma no Hodgkin/clasificación , Antígenos CD/análisis , Antígenos de Diferenciación de Linfocitos B/análisis , Antígenos de Diferenciación de Linfocitos T/análisis , Linfocitos B/inmunología , Linfocitos B/patología , Humanos , Linfoma no Hodgkin/inmunología , Linfoma no Hodgkin/patología , Pronóstico , Estudios Prospectivos , Análisis de Supervivencia , Linfocitos T/inmunología , Linfocitos T/patología
19.
Asia Pac J Oncol Nurs ; 2(3): 186-191, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-27981113

RESUMEN

Breast cancer is the leading cause of cancer in females between the ages of 15 and 54, and the second leading cause of cancer death in women in the United States. Diagnosis begins with detection by breast examination (clinical breast exam or breast self-exam) or by radiologic studies, like mammography. Many advances in the diagnosis of breast cancer have taken place in recent years. This article will review the history of radiologic advances in the diagnosis of breast cancer. Use of technological advancements in digital breast tomosynthesis, magnetic resonance imaging, and ultrasound in breast cancer diagnosis will be presented. Advantages and disadvantages of these diagnostic interventions when compared to older, traditional X-ray films will be discussed. It is important for all nurses, including radiology and oncology nurses, to be well informed about these varied diagnostic modalities, and appreciate the fact that advances in radiologic imaging technologies can yield improved outcomes for breast cancer patients.

20.
Nat Commun ; 6: 8053, 2015 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-26329811

RESUMEN

The theory of superconductivity developed by Bardeen, Cooper and Schrieffer (BCS) explains the stabilization of electron pairs into a spin-singlet, even frequency, state by the formation of an energy gap within which the density of states is zero. At a superconductor interface with an inhomogeneous ferromagnet, a gapless odd frequency superconducting state is predicted, in which the Cooper pairs are in a spin-triplet state. Although indirect evidence for such a state has been obtained, the gap structure and pairing symmetry have not so far been determined. Here we report scanning tunnelling spectroscopy of Nb superconducting films proximity coupled to epitaxial Ho. These measurements reveal pronounced changes to the Nb subgap superconducting density of states on driving the Ho through a metamagnetic transition from a helical antiferromagnetic to a homogeneous ferromagnetic state for which a BCS-like gap is recovered. The results prove odd frequency spin-triplet superconductivity at superconductor/inhomogeneous magnet interfaces.

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