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PURPOSE: The aim of this study was to identify patient-centered, mucositis-associated adverse impact factors and events that might confound physician-assessed oral mucositis (OM) in head and neck cancer (HNC) patients receiving chemoradiotherapy. METHODS: This was a post hoc analysis of a previously conducted randomized trial to determine the efficacy of 5% phenylbutyrate mouthwash in preventing chemoradiotherapy-induced OM. This analysis identified patient-centered symptomatic, observable, and measurable factors that may confound physician scoring of the severity of OM during chemoradiotherapy. Confounding factors were then combined with physician-rated OM scores according to World Health Organization (WHO) and OM Assessment Scale (OMAS) criteria to investigate the therapeutic implications of OM treatment. RESULTS: The original analysis found no significant differences between experimental and placebo groups with respect to the cumulative incidence of physician-recorded severe OM (WHO ≥3 or OMAS ≥2), patient-reported adverse events, and opioid use. However, patients in the experimental arm had relatively lower rates of OM-associated adverse clinical issues including unplanned short radiation breaks, skipping of chemotherapy, nausea/vomiting, late loss of body weight, and early opioid use, all of which could potentially interfere with physician-assessed OM scoring. When WHO OM grade (functional impact and pain), OMAS ulceration size (organic impact), and prolonged radiation treatment time (cancer treatment impact) were combined, there were significantly fewer interruptions of chemoradiotherapy treatment in symptomatic OM patients in the experimental compared to the placebo group. The benefits conferred by reducing the amount of chemoradiotherapy-related, OM-associated adverse impacts in the experimental group were reflected by better 5-year locoregional recurrence-free survival. CONCLUSIONS: This exploratory study raises questions as to whether the severity reflected by physician-rated OM scores is in concordance with OM-induced adverse impacts on HNC patients. Further investigations are warranted to identify patient-related and cancer-associated symptom burdens that may affect tolerance, compliance, and outcome of chemoradiotherapy and confound the evaluation of therapeutic effects on chemoradiotherapy-induced OM.
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Quimioradioterapia/efectos adversos , Neoplasias de Cabeza y Cuello/complicaciones , Estomatitis/etiología , Adulto , Anciano , Quimioradioterapia/métodos , Femenino , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Masculino , Persona de Mediana EdadRESUMEN
We hypothesized the histone deacetylase inhibitor phenylbutyrate (PB) has beneficial effects on radiation-induced injury by modulating the expression of DNA repair and wound healing genes. Hamsters received a radiosurgical dose of radiation (40 Gy) to the cheek and were treated with varying PB dosing regimens. Gross alteration of the irradiated cheeks, eating function, histological changes, and gene expression during the course of wound healing were compared between treatment groups. Pathological analysis showed decreased radiation-induced mucositis, facilitated epithelial cell growth, and preventing ulcerative wound formation, after short-term PB treatment, but not after vehicle or sustained PB. The radiation-induced wound healing gene expression profile exhibited a sequential transition from the inflammatory and DNA repair phases to the tissue remodeling phase in the vehicle group. Sustained PB treatment resulted in a prolonged wound healing gene expression profile and delayed the wound healing process. Short-term PB shortened the duration of inflammatory cytokine expression, triggered repeated pulsed expression of cell cycle and DNA repair-regulating genes, and promoted earlier oscillatory expression of tissue remodeling genes. Distinct gene expression patterns between sustained and short-term treatment suggest dynamic profiling of wound healing gene expression can be an important part of a biological therapeutic strategy to mitigate radiation-related tissue injury.
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Antineoplásicos/farmacología , Transformación Celular Neoplásica/efectos de la radiación , Mucosa Bucal/patología , Neoplasias de la Boca/patología , Fenilbutiratos/farmacología , Traumatismos por Radiación/patología , Cicatrización de Heridas/efectos de los fármacos , Animales , Western Blotting , Proliferación Celular , Cricetinae , Daño del ADN/efectos de la radiación , Reparación del ADN/efectos de la radiación , Modelos Animales de Enfermedad , Regulación Neoplásica de la Expresión Génica , Masculino , Mesocricetus , Neoplasias de la Boca/inducido químicamente , Transducción de SeñalRESUMEN
BACKGROUND: The gut microbiota contributes to macrophage-mediated inflammation in adipose tissue with consumption of an obesogenic diet, thus driving the development of metabolic syndrome. There is a need to identify and develop interventions that abrogate this condition. The hops-derived prenylated flavonoid xanthohumol (XN) and its semi-synthetic derivative tetrahydroxanthohumol (TXN) attenuate high-fat diet-induced obesity, hepatosteatosis, and metabolic syndrome in C57Bl/6J mice. This coincides with a decrease in pro-inflammatory gene expression in the gut and adipose tissue, together with alterations in the gut microbiota and bile acid composition. RESULTS: In this study, we integrated and interrogated multi-omics data from different organs with fecal 16S rRNA sequences and systemic metabolic phenotypic data using a Transkingdom Network Analysis. By incorporating cell type information from single-cell RNA-seq data, we discovered TXN attenuates macrophage inflammatory processes in adipose tissue. TXN treatment also reduced levels of inflammation-inducing microbes, such as Oscillibacter valericigenes, that lead to adverse metabolic phenotypes. Furthermore, in vitro validation in macrophage cell lines and in vivo mouse supplementation showed addition of O. valericigenes supernatant induced the expression of metabolic macrophage signature genes that are downregulated by TXN in vivo. CONCLUSIONS: Our findings establish an important mechanism by which TXN mitigates adverse phenotypic outcomes of diet-induced obesity and metabolic syndrome. TXN primarily reduces the abundance of pro-inflammatory gut microbes that can otherwise promote macrophage-associated inflammation in white adipose tissue. Video Abstract.
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Microbioma Gastrointestinal , Síndrome Metabólico , Animales , Ratones , Síndrome Metabólico/tratamiento farmacológico , ARN Ribosómico 16S/genética , Tejido Adiposo , Obesidad , InflamaciónRESUMEN
We report the first, to the best of our knowledge, experimental implementation of a spinning-disk configuration for high-speed compressive image acquisition. A single rotating mask (i.e., the spinning disk) with random binary patterns was utilized to spatially modulate a collimated terahertz (THz) or IR beam. After propagating through the sample, the THz or IR beam was measured using a single detector, and THz and IR images were subsequently reconstructed using compressive sensing. We demonstrate that a 32-by-32 pixel image could be obtained from 160 to 240 measurements in both the IR and THz ranges. This spinning-disk configuration allows the use of an electric motor to rotate the spinning disk, thus enabling the experiment to be performed automatically and continuously. This, together with its compact design and computational efficiency, makes it promising for real-time imaging applications.
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Peritoneal carcinomatosis (PC) arising from colorectal cancer (CRC) is generally considered a terminal condition with few treatment options. However, over the past few decades, new chemotherapeutic and biologic agents have improved the median overall survival of patients with unresectable metastatic disease up to 20 months. There has also been emergence of combining cytoreductive surgery (CS) with hyperthermic intraperitoneal chemotherapy (HIPEC) for patients with PC. The literature supporting such an approach is significant, though not extensive, mainly consisting of small single-institution series, one international multicenter retrospective review, and one single-institution prospective randomized trial. Yet, there is remarkable homogeneity among the reported clinical outcomes, demonstrating 5-year OS rates of approximately 25-40% for patients undergoing a complete cytoreduction. These studies have fueled increasing interest in the use of CS and HIPEC for metastatic colorectal cancer over the past decade. However, despite the publication of a consensus statement on the role of CS and HIPEC for PC from CRC, there is still controversy regarding its appropriateness, effectiveness, safety, and application in this subset of patients. In this review we analyze the currently available scientific evidence supporting the clinical application of CS and HIPEC in the treatment of PC of colorectal origin.
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Quimioterapia del Cáncer por Perfusión Regional , Neoplasias Colorrectales/terapia , Hipertermia Inducida , Neoplasias Colorrectales/cirugía , HumanosRESUMEN
This study was designed to replicate and extend a previous report that the increase in performance of an attentional set-shifting task (ASST) in rhesus monkeys predicted their future alcohol drinking status as a heavy drinker (HD) or non-heavy drinker (NHD). A cohort of 6 young adult male monkeys was trained and tested under the same ASST and then underwent a alcohol self-administration protocol that maintained open-access (22 hours/day) choice of alcohol or water 7 days/week for approximately 6 months. The average improvement in performance in the ASST, as measured by a performance index, was replicated in the cohort of 6 monkeys when compared to the increase in the task performance in a previous cohort of 9 male monkeys. The alcohol self-administration protocol was then used to determine the drinking status (HD: n = 4 or NHD: n = 2) of the replicate cohort, which was accurately predicted by the performance on the ASST. Finally, individuals from both cohorts could be combined based on future drinking status of HD (n = 8) or NHD (n = 7), and the association with pre-alcohol ASST performance remained. Specifically, monkeys that had lower rates of PI improvement were more likely to become HDs. To our knowledge, this is the first study to replicate that deficits in the set-shifting performance can predict chronic heavy alcohol drinking in primates.
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Intoxicación Alcohólica , Análisis y Desempeño de Tareas , Consumo de Bebidas Alcohólicas , Animales , Etanol , Macaca mulatta , MasculinoRESUMEN
Fungal spondylodiscitis is rare (0.5%-1.6% of spondylodiscitis) and mainly caused by Candida albicans. Surgical intervention in spondylodiscitis patients is indicated for compression of neural elements, spinal instability, severe kyphosis, failure of conservative management and intractable pain. However, there is no evidence-based optimal surgical approach for spondylodiscitis. There have been only case reports of surgical treatment for Candida spondylodiscitis. We evaluated the preliminary results of the efficacy and safety of one-stage debridement via oblique lateral corridor with interbody fusion (OLIF) using stand-alone cement reconstruction after debridement for the treatment of Candida spondylodiscitis in patients with major co-morbidities. Five patients (4 males, 1 female, mean age: 64.2 years) suffering from Candida albicans lumbar spondylodiscitis who underwent this procedure were studied. Their predominant symptoms were unremitting back and leg pain and all had pre and postoperative anti-fungal therapy under microbiologist supervision. The operative time ranged from 137minutes to 260minutes (mean: 213.4minutes). The mean blood loss was 160mL (range: 100-200mL). There were no perioperative complications. At follow-up all showed major improvement in pain and ambulatory status. CT scan showed radiological stability for all patients at 6-12 months. Our preliminary results showed stand-alone anterior debridement and spinal re-construction with cement through mini-open OLIF approach might be a safe and effective option for patients with spinal fungal infection and major comorbidities.
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Antibacterianos/administración & dosificación , Cementos para Huesos/uso terapéutico , Candidiasis/cirugía , Desbridamiento/métodos , Discitis/cirugía , Vértebras Lumbares/cirugía , Anciano , Candida albicans/aislamiento & purificación , Candidiasis/diagnóstico por imagen , Comorbilidad , Desbridamiento/tendencias , Discitis/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Vértebras Lumbares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
We report the effect of alpha-particle irradiation on the reduction of the critical temperature T{c} of a NdFeAs(OF) single crystal. Our data indicate that irradiation defects cause both nonmagnetic and magnetic scattering, resulting in the Kondo-like excess resistance Delta rho(T) proportional to lnT over 2 decades in temperatures above T{c}. The critical density of magnetic irradiation defects which suppresses T{c} is found to be much higher than those for cuprates and multiband BCS superconductors. We suggest that such anomalously weak pair breaking by irradiation defects indicates that magnetic scattering in pnictides is coupled with pairing interactions mediated by spin fluctuations.
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Optical coherence tomography (OCT) is a non-invasive imaging technique routinely used in ophthalmology to visualize and quantify the layers of the retina. It also provides information on optic nerve head topography, peripapillary retinal nerve fiber layer thickness, and macular volume, which correlate with axonal loss. These measurements are of particular interest in optic neuropathies and in multiple sclerosis, and OCT parameters are now used as endpoints in neurologic clinical trials.
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Esclerosis Múltiple/diagnóstico , Neuritis Óptica/diagnóstico , Tomografía de Coherencia Óptica , Axones/patología , Humanos , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple/patología , Enfermedades del Sistema Nervioso/diagnóstico , Enfermedades del Sistema Nervioso/patología , Neuromielitis Óptica/diagnóstico , Neuromielitis Óptica/patología , Neuritis Óptica/tratamiento farmacológico , Neuritis Óptica/patología , Neuronas Retinianas/patología , Resultado del TratamientoRESUMEN
BACKGROUND: Multiple surgical techniques and approaches exist to obtain lumbar interbody fusion. Anterolateral (oblique) is a relatively recent technique. Controversy exists for its use at the L5-S1 level. We performed this study in order to show the safety and efficacy of this technique. The aim of this study was to report the long-term complications and fusion rates of minimally-open (mini-open) anterolateral interbody fusion at the L5-S1 level. METHODS: We retrospectively analyzed all patients who underwent mini-open anterolateral interbody fusion for L5-S1 level in our department. The data collected were the following: age, sex, surgical indication, acute (less than four weeks) and long-term complications (>3 months), fusion at six months and length of follow-up. RESULTS: Seventeen patients (8M/9F) underwent mini-open anterolateral interbody fusion at L5-S1. The mean age was 64.5 years. The surgical indication was scoliosis in 10 cases, flat back in 4 cases, and spondylolisthesis in 3 cases. All patients underwent a complementary posterior procedure that included fixation. Mean blood loss was 252.9mL for the anterior procedure. Eight acute and minor complications occurred (anemia, delirium, and psoas paresis). Two acute complications required surgical intervention (cage displacement and hematoma). Long-term complications were observed in 2 cases and included proximal junction kyphosis and non-union. The fusion rate was evaluated at 88%. The mean follow-up period was 28.3 months. CONCLUSIONS: Mini-open anterolateral interbody fusion at the L5-S1 level is safe and results in fusion at the same rate as anterior interbody fusion. Most acute complications are minor and resolve spontaneously.
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Complicaciones Posoperatorias/terapia , Fusión Vertebral/efectos adversos , Adulto , Pérdida de Sangre Quirúrgica , Femenino , Estudios de Seguimiento , Humanos , Región Lumbosacra/cirugía , Masculino , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/cirugía , Estudios Retrospectivos , Resultado del Tratamiento , Adulto JovenRESUMEN
In addition to genetic changes, epigenetic aberrations also play important roles in radiation- and chemical-induced disorders and carcinogenesis. The present study investigated whether epigenetic therapy with a histone deacetylase (HDAC) inhibitor has dual benefits for radiation-induced oral mucositis and chemical-induced oral carcinogenesis, which should be treated at the same time. The HDAC inhibitor phenylbutyrate was first tested to determine if it influences DNA damage repair and survival in irradiated normal cells in vitro by investigating the patterns and dynamics of phospho-gammaH2AX foci, Rad51 foci and phospho-gammaH2AX/Rad51 colocalization and using the comet and clonogenic assays. Oral mucositis or carcinogenesis was induced in hamsters using radiation or 7,12-dimethylbenz[a]anthracene (DMBA) irritation to the cheek pouch. The ability of phenylbutyrate formed in proper carriers to prevent radiation-induced oral mucositis and inhibit chemical-induced oral carcinogenesis was assessed. The treated or untreated irradiated or DMBA-irritated oral tissues or mucosal epithelia were subjected to the studies of histology, immunohistochemistry, gene expression, comet assay, HDAC activity or oxidative stress. We found that phenylbutyrate promoted DNA repair and survival in normal cells after radiation. Compared with blank or vehicle-treated hamsters, the irradiated mucosa treated with phenylbutyrate had significantly lower oxidative stress and tumor necrosis factor-alpha expression and less severe oral mucositis of a shorter duration. A reduction of the oral tumor incidence, burden and progression by phenylbutyrate correlated with the suppression of oncomiRs and Rad51 overexpression, the upregulation of differentiation markers and the decrease of intracellular HDAC activity and oxidative stress during DMBA-induced oral carcinogenesis. Thus, epigenetic therapy using the HDAC inhibitor as an adjuvant to radiotherapy for chemical-induced oral cancer may provide a promising strategy combining the prevention of radiation-induced oral mucositis and the inhibition of oral carcinogenesis.
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Antineoplásicos/farmacología , Inhibidores Enzimáticos/farmacología , Inhibidores de Histona Desacetilasas , Neoplasias de la Boca/prevención & control , Fenilbutiratos/farmacología , Traumatismos por Radiación/prevención & control , Estomatitis/prevención & control , 9,10-Dimetil-1,2-benzantraceno/toxicidad , Acetilación/efectos de los fármacos , Administración Oral , Animales , Apoptosis , Western Blotting , Transformación Celular Neoplásica , Células Cultivadas , Cricetinae , Daño del ADN/efectos de los fármacos , Daño del ADN/efectos de la radiación , Reparación del ADN/efectos de los fármacos , Reparación del ADN/efectos de la radiación , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Fibroblastos/efectos de la radiación , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de la radiación , Histona Desacetilasas/genética , Histona Desacetilasas/metabolismo , Histonas/metabolismo , Humanos , Técnicas para Inmunoenzimas , Masculino , Mesocricetus , Neoplasias de la Boca/inducido químicamente , Neoplasias de la Boca/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Recombinasa Rad51/metabolismo , Tolerancia a Radiación/efectos de los fármacos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Estomatitis/inducido químicamente , Estomatitis/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Zn(5)Sb(4)In(2-delta) (delta = 0.15(3)) was synthesized in the form of millimeter-sized crystals from reaction mixtures containing excess zinc. The ternary intermetallic compound is temperature polymorphic, and at room temperature it crystallizes with a new structure type in the orthorhombic space group Pbcn, where a = 7.1619(2), b = 17.1562(4), c = 8.6887(4) A, V = 1067.6(1) A(3), and Z = 4. The structure features 3(2)434 nets of Sb atoms that are stacked in antiposition to yield layers of square antiprisms sharing edges plus intervening tetracapped tetrahedra (tetreadersterns). The majority of Zn atoms occupy peripheral tetrahedra of such tetraedersterns, and attain at the same time the peculiar five-coordination by one like atom and four Sb atoms typical for the structures of binary zinc antimonides. The In and remaining Zn atoms are distributed in the tetragonal channels formed by the square antiprisms and display some disorder. At temperatures below 200 K Zn(5)Sb(4)In(2-delta) undergoes a phase transition into a more ordered structure with monoclinic symmetry (P2(1)/c) without any change of the unit cell. The thermoelectric properties of Zn(5)Sb(4)In(2-delta) were measured between 10 and 350 K. Exceptionally low thermal conductivity values (1 W/mK range) were obtained in the whole temperature range. Resistivity and thermopower values are characteristic of a heavily doped or degenerate semiconductor (2.5 mOmega cm and 160 muV/K, respectively, at room temperature) and show a discontinuity around 220 K. The thermoelectric figure of merit of Zn(5)Sb(4)In(2-delta) is higher than that of Zn(4)Sb(3) in the investigated temperature range.
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OBJECTIVE: To compare French and American white patients with idiopathic intracranial hypertension (IIH), and to determine prognostic factors associated with visual loss. METHODS: Medical records of all consecutive white patients with definite IIH seen between 2001 and 2006 in three French tertiary care medical centers and one American tertiary medical center were reviewed. Demographics, associated clinical features, and visual function at presentation and follow-up were collected. French white patients were compared to American white patients. RESULTS: One hundred and thirty-four patients (66 French, 68 American) were included. American patients were 8.7 times more likely than French patients to have visual acuity 20/60 or worse or visual field constriction (95% CI: 2.1-36.1, p=0.0001). American patients were treated more aggressively than French patients. French patients were older (31 vs. 28 years, p=0.02) and more likely to have anemia (20 vs. 2%, p<0.001). American patients had a longer duration of symptoms prior to diagnosis (12 vs. 4 weeks, p=0.01) and longer follow-up than French patients (26 vs. 11 months, p=0.001). Multivariable analysis found that nationality was an independent risk factor for visual loss. French and American patients did not differ regarding gender proportion, frequency of obesity, sleep apnea, endocrine diseases, or systemic hypertension. Cerebrospinal fluid (CSF) opening pressures were similar in both groups. CONCLUSION: American patients with IIH had worse visual outcomes than French patients despite more aggressive treatment. These differences are not explained by differences in previously known risk factors.
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Hipertensión Intracraneal/epidemiología , Adolescente , Adulto , Peso Corporal/fisiología , Presión del Líquido Cefalorraquídeo/fisiología , Femenino , Francia/epidemiología , Humanos , Hipertensión Intracraneal/complicaciones , Hipertensión Intracraneal/fisiopatología , Masculino , Persona de Mediana Edad , América del Norte/epidemiología , Estudios Retrospectivos , Factores Socioeconómicos , Trastornos de la Visión/epidemiología , Trastornos de la Visión/etiología , Pruebas de Visión , Agudeza Visual , Población Blanca , Adulto JovenRESUMEN
AIM: Demographic factors potentially influencing the presentation and severity of idiopathic intracranial hypertension (IIH) in the US vs. UK populations include obesity and ethnicity. We aimed to compare the presenting features of IIH between populations in the UK and US tertiary referral centres, to assess what population differences exist and whether these cause different presentations and impact on visual function. METHODS: Clinical data were collected on 243 consecutive UK IIH patients and 469 consecutive US IIH patients seen after 2012 in two tertiary centres. Visual function was defined as severe visual loss when Humphrey visual field mean deviation was <-15 dB, when Goldmann visual fields showed constriction or when visual acuity was <20/200. RESULTS: US patients were more commonly of self-reported black race (58.9% vs. 7.1%) than UK patients, but had a similar mean body mass index (38.3 ± 0.63kg/m2 UK vs. 37.7 ± 0.42kg/m2 US; p = 0.626). The UK cohort had lower presenting Frisén grade (median 1 vs. 2; p < 0.001) and severe visual loss less frequently (15.4% vs. 5%; p = 0.014), but there was no difference in mean cerebrospinal fluid-opening pressure (CSF-OP) (35.8 ± 0.88cmH2O UK vs. 36.3 ± 0.52cmH2O US; p = 0.582). African Americans had poorer visual outcomes compared with US whites (19.4% vs. 10% severe visual loss; p = 0.011). Visual function was weakly associated with CSF-OP (R2 = 0.059; p = 0.001), which was similar between UK and US patients. CONCLUSIONS: The UK and the US cohorts had a similar average presenting BMI. However, the worse presenting visual function in the US IIH cohort was partially attributable to differences in the black populations in the two countries.
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Presión del Líquido Cefalorraquídeo/fisiología , Seudotumor Cerebral/fisiopatología , Trastornos de la Visión/etiología , Agudeza Visual , Adolescente , Adulto , Índice de Masa Corporal , Femenino , Humanos , Incidencia , Masculino , Seudotumor Cerebral/complicaciones , Seudotumor Cerebral/epidemiología , Reino Unido/epidemiología , Estados Unidos/epidemiología , Trastornos de la Visión/epidemiología , Trastornos de la Visión/fisiopatología , Adulto JovenRESUMEN
The metastable binary intermetallic compound Cd4Sb3 was obtained as polycrystalline ingot by quenching stoichiometric Cd-Sb melts and as mm-sized crystals by employing Bi or Sn fluxes. The compound crystallizes in the monoclinic space group Pn with a = 11.4975(5) A, b = 26.126(1) A, c = 26.122(1) A, beta = 100.77(1) degrees, and V = 7708.2(5) A(3). The actual formula unit of Cd4Sb3 is Cd13Sb10 and the unit cell contains 156 Cd and 120 Sb atoms (Z = 12). Cd4Sb3 displays a reversible order-disorder transition at 373 K and decomposes exothermically into a mixture of elemental Cd and CdSb at around 520 K. Disordered beta-Cd4Sb3 is rhombohedral (space group R3c, a approximately = 13.04 A, c approximately = 13.03 A) with a framework isostructural to beta-Zn4Sb3. The structure of monoclinic alpha-Cd4Sb3 bears resemblance to the low-temperature modifications of Zn4Sb3, alpha- and alpha'-Zn4Sb3, in that randomly distributed vacancies and interstitial atoms of the high-temperature modification aggregate and order into distinct arrays. However, the nature of aggregation and distribution of aggregates is different in the two systems. Cd4Sb3 displays the properties of a narrow gap semiconductor. Between 10 and 350 K the resistivity of melt-quenched samples first increases with increasing temperature until a maximum value at 250 K and then decreases again. The resistivity maximum is accompanied with a discontinuity in the thermopower, which is positive and increasing from 10 to 350 K. The room temperature values of the resistivity and thermopower are about 25 mohms cm and 160 microV/K, respectively. Flux synthesized samples show altered properties due to the incorporation of small amounts of Bi or Sn (less than 1 at. %). Thermopower and resistivity appear drastically increased for Sn doped samples. Characteristic for Cd4Sb3 samples is their low thermal conductivity, which drops below 1 W/mK above 130 K and attains values around 0.75 W/mK at room temperature, which is comparable to vitreous materials.
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BACKGROUND: Acute isolated optic neuritis is often the first manifestation of multiple sclerosis (MS). Despite the results of several clinical trials its management remains controversial. With the advent of new disease-modifying agents for the treatment of MS, management of isolated optic neuritis has become more complicated. The goal of this study was to evaluate the current clinical practice of French ophthalmologists and neurologists in the management of acute isolated optic neuritis, and to evaluate the impact of recently published randomized clinical trials on their practice. METHODS: A survey, including 24 questions on the diagnosis and treatment of acute isolated optic neuritis was sent to all neurologists and to a sample of ophthalmologists in France. RESULTS: The responses of 655 neurologists and 141 ophthalmologists were analyzed. This study shows mostly that patients initially present more frequently to ophthalmologists, and are subsequently referred to neurologists. Most optic neuritis patients undergo a brain MRI and a lumbar puncture. Although most patients receive high dose intravenous steroids, up to 15% of neurologists and 21% of ophthalmologists still recommend oral prednisone (1 mg/kg per day). Steroids are often prescribed for the wrong reason, including to improve final visual acuity or decrease the risk of MS. Disease modifying agents are sometimes prescribed outside of the official French recommendations. CONCLUSION: The evidence-based guidelines are only partially followed by practitioners managing patients with acute optic neuritis.
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Neurología/tendencias , Oftalmología/tendencias , Neuritis Óptica/terapia , Antiinflamatorios/administración & dosificación , Antiinflamatorios/uso terapéutico , Recolección de Datos , Utilización de Medicamentos , Francia/epidemiología , Humanos , Factores Inmunológicos/uso terapéutico , Inyecciones Intravenosas , Imagen por Resonancia Magnética , Esclerosis Múltiple/complicaciones , Neuritis Óptica/epidemiología , Prednisona/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Derivación y Consulta/estadística & datos numéricos , Punción Espinal , Esteroides/administración & dosificación , Esteroides/uso terapéutico , Agudeza VisualRESUMEN
BACKGROUND AND PURPOSE: Intracranial pressure is estimated invasively by using lumbar puncture with CSF opening pressure measurement. This study evaluated displacement encoding with stimulated echoes (DENSE), an MR imaging technique highly sensitive to brain motion, as a noninvasive means of assessing intracranial pressure status. MATERIALS AND METHODS: Nine patients with suspected elevated intracranial pressure and 9 healthy control subjects were included in this prospective study. Controls underwent DENSE MR imaging through the midsagittal brain. Patients underwent DENSE MR imaging followed immediately by lumbar puncture with opening pressure measurement, CSF removal, closing pressure measurement, and immediate repeat DENSE MR imaging. Phase-reconstructed images were processed producing displacement maps, and pontine displacement was calculated. Patient data were analyzed to determine the effects of measured pressure on pontine displacement. Patient and control data were analyzed to assess the effects of clinical status (pre-lumbar puncture, post-lumbar puncture, or control) on pontine displacement. RESULTS: Patients demonstrated imaging findings suggesting chronically elevated intracranial pressure, whereas healthy control volunteers demonstrated no imaging abnormalities. All patients had elevated opening pressure (median, 36.0 cm water), decreased by the removal of CSF to a median closing pressure of 17.0 cm water. Patients pre-lumbar puncture had significantly smaller pontine displacement than they did post-lumbar puncture after CSF pressure reduction (P = .001) and compared with controls (P = .01). Post-lumbar puncture patients had statistically similar pontine displacements to controls. Measured CSF pressure in patients pre- and post-lumbar puncture correlated significantly with pontine displacement (r = 0.49; P = .04). CONCLUSIONS: This study establishes a relationship between pontine displacement from DENSE MR imaging and measured pressure obtained contemporaneously by lumbar puncture, providing a method to noninvasively assess intracranial pressure status in idiopathic intracranial hypertension.
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Imagen por Resonancia Magnética/métodos , Seudotumor Cerebral/diagnóstico por imagen , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Punción EspinalRESUMEN
OBJECTIVE: To describe the characteristics of patients with homonymous hemianopia from traumatic brain injury (TBI) seen in our unit between 1989 and 2004. METHODS: Only patients with a history of TBI, who had detailed clinical information and results of neuroimaging, were included in our study. Demographic characteristics, clinical features, types of visual field defects, location of lesion and evolution of visual field defects were recorded. RESULTS: Of the 880 patients with homonymous hemianopia seen in our unit, 103 patients (112 with homonymous hemianopia) had TBI (74 men and 29 women, mean age 30.7 (SD 15.3) years). Median time from injury to initial visual field testing was 5 (range 0.5-360) months. In all, 64 (57.1%) patients sustained injuries that were motor vehicle-related; 19 (17%) violence-related; 17 (15.2%) due to falls; and 12 (10.7%) because of other blunt head trauma. Visual field defects included complete homonymous hemianopia in 44 (39.3%) patients and incomplete homonymous hemianopia in 68 (60.7%) patients. The lesion was occipital in 14 (12.5%) patients, associated with optic radiation in 26 (23.2%) and the optic tract in 12 (10.7%), and multiple in 60 (53.6%). CONCLUSION: Most cases of homonymous hemianopia from TBI were motor vehicle-related. Patients were younger, more often male, and had multiple brain lesions more often than patients with homonymous hemianopia from causes other than TBI. A median delay of 5 months was observed before the documentation of the homonymous hemianopia, which may have a major effect on the success of rehabilitation and driving training in these young patients.