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AIMS: Accurate identification of dermatophytes is essential for implementing appropriate antifungal treatment and epidemiological analysis. However, the limitations of conventional diagnostics are a frequently discussed topic, and new diagnostic techniques are constantly expanding. In this study, we assess the suitability of conventional diagnostic techniques in comparison to the real-time PCR assay and MALDI-TOF MS in detection and identification of dermatophytes. METHODS AND RESULTS: Strains included in this study were obtained from human and animals with symptomatic, and asymptomatic infection. A direct examination revealed that 31·7 and 60·9% of samples from symptomatic patients, and 25·7 and 60% from asymptomatic animals were positive, as shown by light and fluorescence microscopy respectively. In turn, dermatophytes were isolated from 90·2 and 71·4% of these samples. The pan-dermatophyte primers in real-time PCR assay facilitated detection in 85·3 and 82·9% of the symptomatic and asymptomatic dermatophytoses respectively. Additionally, species-specific PCR assays were positive in 70·7 and 37·1% of these samples. The MALDI-TOF MS analysis yielded positive results consistent with conventional techniques in 97·2 and 72% of symptomatic and asymptomatic infections respectively. CONCLUSIONS: Our study revealed that there is no universal diagnostic method that would be ideal in each of the cases considered. Nonetheless, conventional techniques are still the most effective and reliable tools for mycological diagnostics. SIGNIFICANCE AND IMPACT OF THE STUDY: Dermatologists and veterinarians have difficulties in making a diagnosis of dermatophytoses based only on observed symptoms of fungal infections, as they mimic symptoms of other dermatoses. In this context, a comparative analysis of the results of diagnostics performed using conventional methods and new technologies are crucial for implementing these pioneer methods into routine laboratory practice.
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Arthrodermataceae/clasificación , Arthrodermataceae/aislamiento & purificación , Técnicas de Tipificación Micológica/métodos , Animales , Arthrodermataceae/química , Arthrodermataceae/genética , Dermatomicosis/microbiología , Pruebas Diagnósticas de Rutina , Humanos , Reacción en Cadena en Tiempo Real de la Polimerasa , Espectrometría de Masa por Láser de Matriz Asistida de Ionización DesorciónRESUMEN
African Americans have an increased risk of cardiovascular disease partly due to low fruit and vegetable consumption. This article reports the results of an intervention to provide nutrition education and access to fruits and vegetables through community gardens to change dietary behaviors among African Americans in rural Missouri. Cross-sectional surveys evaluated the intervention effect on blood pressure, body mass index (BMI), and perceived fruit and vegetable consumption in this quasi-experimental study with a comparison group. Hypertension (OR = 0.52, 95% CI: 0.38-0.71) and BMI (OR = 0.73, 95% CI: 0.52-1.02) were lower in the intervention county at mid-intervention. Participation in nutrition education (OR = 2.67, 95% CI: 1.63-4.40) and access to fruits and vegetables from a community garden (OR = 1.95, 95% CI: 1.20-3.15) were independently associated with perceived fruit and vegetable consumption. The strongest effect on perceived fruit and vegetable consumption occurred with high participation in nutrition education and access to community gardens (OR = 2.18, 95% CI: 1.24-3.81). Those with access but without education had a reduced likelihood of consuming recommended servings of fruits and vegetables (OR = 0.57, 95% CI: 0.34-0.95). Education plus access interventions may be best at increasing consumption of fruits and vegetables in a rural African American population.
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Negro o Afroamericano , Enfermedades Cardiovasculares/prevención & control , Dieta/estadística & datos numéricos , Frutas , Educación en Salud/métodos , Verduras , Adulto , Enfermedades Cardiovasculares/epidemiología , Estudios Transversales , Demografía , Femenino , Humanos , Masculino , Missouri/epidemiología , Población RuralRESUMEN
Conventional semiconductor devices use electric fields to control conductivity, a scalar quantity, for information processing. In magnetic materials, the direction of magnetization, a vector quantity, is of fundamental importance. In magnetic data storage, magnetization is manipulated with a current-generated magnetic field (Oersted-Ampère field), and spin current is being studied for use in non-volatile magnetic memories. To make control of magnetization fully compatible with semiconductor devices, it is highly desirable to control magnetization using electric fields. Conventionally, this is achieved by means of magnetostriction produced by mechanically generated strain through the use of piezoelectricity. Multiferroics have been widely studied in an alternative approach where ferroelectricity is combined with ferromagnetism. Magnetic-field control of electric polarization has been reported in these multiferroics using the magnetoelectric effect, but the inverse effect-direct electrical control of magnetization-has not so far been observed. Here we show that the manipulation of magnetization can be achieved solely by electric fields in a ferromagnetic semiconductor, (Ga,Mn)As. The magnetic anisotropy, which determines the magnetization direction, depends on the charge carrier (hole) concentration in (Ga,Mn)As. By applying an electric field using a metal-insulator-semiconductor structure, the hole concentration and, thereby, the magnetic anisotropy can be controlled, allowing manipulation of the magnetization direction.
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INTRODUCTION: Stasis filling, defined as delayed, weak, and persistent opacification of proximal segments of the cerebral arteries, is frequently found in brain dead patients. This phenomenon causes a major problem in the development of reliable computed tomographic angiography (CTA) protocol in the diagnosis of brain death (BD). The aim of our study was to characterize stasis filling in the diagnosis of BD. To achieve this, we performed a dynamic evaluation of contrast enhancement of the cerebral and extracranial arteries in patients with BD and controls. METHODS: Study population included 30 BD patients, who showed stasis filling in computed tomographic perfusion (CTP) series. Thirty patients, after clipping of an intracranial aneurysm, constituted the control group. The study protocol consisted of CTA, CTP, and angiography. Time-density curves (TDCs) of cerebral and extracranial arteries were generated using 40-s series of CTP. RESULTS: Cerebral TDCs in BD patients represented flat curves in contrast to TDCs in controls, which formed steep and narrow Gaussian curves. We found longer time to peak enhancement in BD patients than in controls (32 vs. 21 s; p < 0.0001). In BD patients, peak enhancement in the cerebral arteries occurred with a median delay of 14.5 s to peak in extracranial arteries, while no delay was noted in controls (p < 0.0001). Cerebral arteries in BD patients showed lower peak enhancement than controls (34.5 vs. 81.5 HU; p < 0.0001). In all BD patients, CTP revealed zero values of cerebral blood flow and volume. Angiography showed stasis filling in 14 (46.7 %) and non-filling in 16 (53.3 %) cases. CONCLUSION: A confrontation of stasis filling with CTP results showed that stasis filling is not consistent with preserved cerebral perfusion, thus does not preclude diagnosis of BD.
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Muerte Encefálica , Angiografía Cerebral/métodos , Arterias Cerebrales/diagnóstico por imagen , Trastornos Cerebrovasculares/complicaciones , Trastornos Cerebrovasculares/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto JovenRESUMEN
We use SrTiO3/Si as a model system to elucidate the effect of the interface on ferroelectric behavior in epitaxial oxide films on silicon. Using both first-principles computations and synchrotron x-ray diffraction measurements, we show that structurally imposed boundary conditions at the interface stabilize a fixed (pinned) polarization in the film but inhibit ferroelectric switching. We demonstrate that the interface chemistry responsible for these phenomena is general to epitaxial silicon-oxide interfaces, impacting on the design of silicon-based functional oxide devices.
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BACKGROUND: In the diagnosis of brain death (BD), computed tomography angiography (CTA) results in some cases show intracranial filling, leading to diagnostic confusion. Because cerebral circulatory arrest commences at the capillary level, we hypothesized that computed tomography perfusion (CTP) would be a more sensitive approach than CTA; therefore, the aim of the study was to compare the sensitivities of CTP and CTA in the diagnosis of BD. MATERIAL AND METHODS: Whole brain CTP was performed in patients in the intensive care unit diagnosed with BD and CTA was derived from CTP datasets. Cerebral blood flow (CBF) and volume (CBV) were calculated in all brain regions. The CTP findings were interpreted as being consistent with a diagnosis of BD (positive) when CBF and CBV in all regions of interest (ROIs) were below 10 ml/100 g/min and 1.0 ml/100 g, respectively. The CTA findings were interpreted using a 4-point grading system. RESULTS: A total of 50 patients were included in the study. The CTP results revealed CBF from 0.00 to 9.98 ml/100 g/min (mean, 1.98 ± 1.68 ml/100 g/min) and CBV from 0.00 to 0.99 ml/100 g (mean, 0.14 ± 0.12 ml/100 g) and were thus interpreted as positive in all 50 patients. In contrast, the CTA results suggested 7 negative cases, providing a sensitivity of 86%. The difference between the CTP and CTA sensitivity results for the diagnosis of BD was statistically significant (p = 0.006). CONCLUSION: Whole brain CTP may potentially be a feasible and highly sensitive test for diagnosing BD: therefore, performing CTP in combination with CTA in cases when CTA results are negative for BD could increase the sensitivity of CTA.
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Muerte Encefálica/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Anciano , Volumen Sanguíneo , Encéfalo/irrigación sanguínea , Encéfalo/diagnóstico por imagen , Angiografía Cerebral/métodos , Circulación Cerebrovascular , Angiografía por Tomografía Computarizada , Reacciones Falso Negativas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Adulto JovenRESUMEN
OBJECTIVE: Lung cancer (LC) is diagnosed mostly in advanced, non-operable stage, with poor prognosis. The analysis of microRNAs may be a useful tool for early and non-invasive detection of cancer. Dicer and Drosha are enzymes with an essential role for microRNA biogenesis. The aim of our study was to analyze the expression of miRNA-27a-3p, miRNA-31, miRNA-182, miRNA-195 with the ability to reciprocal regulation of Dicer and Drosha expression in lung cancer patients. PATIENTS AND METHODS: The relative expression of microRNAs was detected by qPCR in plasma of 160 LC patients. The U-Mann Whitney test was used to compare the relative expression between particular groups of lung cancer patients and healthy individuals. The diagnostic value of microRNAs examination was analyzed using a receiver operating curve. RESULTS: We demonstrated that the plasma levels of miRNA-27, miRNA-31 and miRNA-182 were significantly higher and miRNA-195 significantly lower in the whole group of LC patients and in patients with early stages of NSCLC, in comparison with healthy donors. ROC analysis showed that four studied microRNAs have a potential diagnostic value for early stages of NSCLC with AUC=0.95 for miRNA-27a (94% sensitivity and 81% specificity, p=0.0001), 0.71 for miRNA-31 (73% sensitivity and 61% specificity, p=0.001) 0.77 for miRNA-182 (70% sensitivity and 79% specificity, p=0.0001) and 0.82 for miRNA-195 (74% sensitivity and 80% specificity, p=0.0001). CONCLUSIONS: We have proved that the expression of miRNA-27a-3p, miRNA-31, miRNA-182, and miRNA-195 in patients with LC is different from the expression of these molecules in healthy people. The examination of these microRNAs in plasma could be used in non-invasive lung cancer diagnosis.
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ARN Helicasas DEAD-box/genética , Neoplasias Pulmonares/diagnóstico , MicroARNs/metabolismo , Ribonucleasa III/genética , Anciano , Área Bajo la Curva , ARN Helicasas DEAD-box/metabolismo , Detección Precoz del Cáncer , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Masculino , MicroARNs/genética , Persona de Mediana Edad , Curva ROC , Ribonucleasa III/metabolismo , Sensibilidad y EspecificidadRESUMEN
A patient with a brain injury fulfilled all clinical criteria for brainstem death diagnosis. Two standard sets of tests were performed; according to Polish regulations, the patient could be declared brain dead. However, shortly after the completion of the tests and before the final brain death declaration, 6 triggered "assisted" breaths/min were noticed. After careful analysis of the ventilator settings, it was concluded that low trigger sensitivity and airway pressure oscillations during heart contractions were the reasons. Additionally, a few minutes later, spontaneous jerking movements of lower limbs and clonic movements of neck muscles secondary to painful stimuli were noticed. The situation became confusing; therefore, cerebral Doppler sonography was performed, showing circulatory arrest in both of the internal carotid, middle cerebral, and left vertebral arteries. The basilar artery was not visualized. Forward flow with increased pulsatility was recorded in extracranial and intracranial segments of the right vertebral artery. Cerebral circulatory arrest was still uncertain; therefore, the diagnostic procedures were completed with conventional cerebral angiography, which showed a lack of cerebral blood flow. Finally, the patient was declared brain dead; kidneys and bones were harvested. Cardiogenic oscillations associated with incorrect low ventilator trigger settings may falsely suggest persistence of breathing efforts in a brain-dead patient. In the case of any unusual events during brain death diagnosis, cerebral perfusion tests should be performed with cerebral angiography as the "gold standard."
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Muerte Encefálica/fisiopatología , Circulación Cerebrovascular/fisiología , Movimiento/fisiología , Fenómenos Fisiológicos Respiratorios , Donantes de Tejidos , Encéfalo/diagnóstico por imagen , Traumatismos Craneocerebrales , Humanos , Masculino , Persona de Mediana Edad , Pulso Arterial , Recolección de Tejidos y Órganos , Tomografía Computarizada por Rayos XRESUMEN
The Fermi level position in (Ga,Mn)N has been determined from the period-analysis of GaN-related Franz-Keldysh oscillation obtained by contactless electroreflectance in a series of carefully prepared by molecular beam epitaxy GaN/Ga1-xMnxN/GaN(template) bilayers of various Mn concentration x. It is shown that the Fermi level in (Ga,Mn)N is strongly pinned in the middle of the band gap and the thickness of the depletion layer is negligibly small. For x > 0.1% the Fermi level is located about 1.25-1.55 eV above the valence band, that is very close to, but visibly below the Mn-related Mn2+/Mn3+ impurity band. The accumulated data allows us to estimate the Mn-related band offsets at the (Ga,Mn)N/GaN interface. It is found that most of the band gap change in (Ga,Mn)N takes place in the valence band on the absolute scale and amounts to -0.028 ± 0.008 eV/% Mn. The strong Fermi level pinning in the middle of the band gap, no carrier conductivity within the Mn-related impurity band, and a good homogeneity enable a novel functionality of (Ga,Mn)N as a semi-insulating buffer layers for applications in GaN-based heterostuctures.
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(Ga,Mn)As having a wurtzite crystal structure was coherently grown by molecular beam epitaxy on the {1100} side facets of wurtzite (Ga,In)As nanowires and further encapsulated by (Ga,Al)As and low temperature GaAs. For the first time, a truly long-range ferromagnetic magnetic order is observed in non-planar (Ga,Mn)As, which is attributed to a more effective hole confinement in the shell containing Mn by the proper selection/choice of both the core and outer shell materials.
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PURPOSE: RT-PCR technique has showed a promising value as pre-screening method for detection of mRNA containing abnormal ALK sequences, but its sensitivity and specificity is still discussable. Previously, we determined the incidence of ALK rearrangement in CNS metastases of NSCLC using IHC and FISH methods. MATERIALS: We evaluated ALK gene rearrangement using two-step RT-PCR method with EML4-ALK Fusion Gene Detection Kit (Entrogen, USA). The studied group included 145 patients (45 females, 100 males) with CNS metastases of NSCLC and was heterogeneous in terms of histology and smoking status. RESULTS: 21% of CNS metastases of NSCLC (30/145) showed presence of mRNA containing abnormal ALK sequences. FISH and IHC tests confirmed the presence of ALK gene rearrangement and expression of ALK abnormal protein in seven patients with positive result of RT-PCR analysis (4.8% of all patients, 20% of RT-PCR positive patients). RT-PCR method compared to FISH analysis achieved 100% of sensitivity and only 82.7% of specificity. IHC method compared to FISH method indicated 100% of sensitivity and 97.8% of specificity. In comparison to IHC, RT-PCR showed identical sensitivity with high number of false positive results. CONCLUSION: Utility of RT-PCR technique in screening of ALK abnormalities and in qualification patients for molecularly targeted therapies needs further validation.
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Biomarcadores de Tumor/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias del Sistema Nervioso Central/secundario , Reordenamiento Génico , Proteínas Tirosina Quinasas Receptoras/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Adenocarcinoma/genética , Adenocarcinoma/patología , Adulto , Anciano , Quinasa de Linfoma Anaplásico , Carcinoma de Células Grandes/genética , Carcinoma de Células Grandes/patología , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Neoplasias del Sistema Nervioso Central/genética , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , PronósticoRESUMEN
We present the case where immune thrombocytopenia (ITP) and essential thrombocythemia (ET) sequentially appeared in the space of twenty-one years of follow-up. Impaired platelet production is present in both diseases, but clinical presentation and treatment are different. On the basis of this case history a possible role of autoimmunity as a predisposing factor to myeloproliferation has been discussed.
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Pancreatic endocrine tumors occur both sporadically and as part of the multiple endocrine neoplasia type 1 (MEN1) syndrome. MEN1 is an autosomal dominant disease characterized by parathyroid hyperplasia, pancreatic endocrine tumors, and pituitary adenomas. The MEN1 gene called MENIN maps to chromosome 11q13 and is thought to function as a tumor suppressor gene. We previously demonstrated loss of heterozygosity (LOH) at 11q13 in approximately 40% of sporadic pancreatic endocrine tumors and hypothesize that MENIN is involved in the development of these tumors. Thirty-one sporadic pancreatic endocrine tumors were analyzed for mutation of MENIN by nonradioactive single-stranded conformation polymorphism. Twelve mutations were detected in 31 sporadic pancreatic endocrine tumors (34%). Twelve of these 31 tumors previously demonstrated loss of heterozygosity at 11q13. Of the tumors with LOH, seven contained mutations of the MENIN gene (58%). The majority of the MENIN mutations occurred within exon 2. Two independent mutations in MENIN were detected in a gastrinoma that also revealed LOH, leading to the possibility of another tumor suppressor gene locus at 11q13. Mutations were present in both benign and malignant pancreatic endocrine tumors, suggesting that a MENIN gene mutation is a frequent and early event in the tumorigenesis. The high incidence of truncating mutations in tumors with LOH at 11q13 support the hypothesis that MENIN is a tumor suppressor gene.
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Cromosomas Humanos Par 11 , Pérdida de Heterocigocidad , Neoplasia Endocrina Múltiple Tipo 1/genética , Proteínas de Neoplasias/genética , Neoplasias Pancreáticas/genética , Mutación Puntual , Proteínas Proto-Oncogénicas , Eliminación de Secuencia , Sustitución de Aminoácidos , Secuencia de Bases , Mapeo Cromosómico , Clonación Molecular , Cartilla de ADN , Exones , Gastrinoma/genética , Gastrinoma/patología , Gastrinoma/cirugía , Genes Supresores de Tumor , Humanos , Insulinoma/genética , Insulinoma/patología , Insulinoma/cirugía , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-SimpleRESUMEN
Endocrine tumors, such as parathyroid adenomas and pheochromocytomas, frequently have deletions of chromosome 1, suggesting that inactivation of a tumor suppressor gene from chromosome 1 is important in their tumorigenesis. We hypothesized that deletion of chromosome 1 may contribute to pancreatic endocrine tumor formation. Twenty-nine sporadic and MEN1 pancreatic endocrine tumors were studied for loss of heterozygosity (LOH) with 12 chromosome 1 microsatellite markers. LOH on chromosome 1 was identified in 10 of 29 (34%) tumors studied. Allele loss occurred more frequently in tumors with hepatic metastases (7 of 8) than tumors without metastases (3 of 21) (P = 0.004). Tumors in patients with lymph node involvement and patients with multiple endocrine neoplasia type 1 did not demonstrate LOH for chromosome 1 markers. These data suggest that loss of chromosome 1 is associated specifically with the development of hepatic metastases in patients with sporadic pancreatic endocrine tumors.
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Cromosomas Humanos Par 1 , Pérdida de Heterocigocidad , Neoplasias Pancreáticas/genética , Genes Supresores de Tumor , Humanos , PronósticoRESUMEN
Polish brain death (BD) criteria established in 2007 are currently under review and therefore all reports about any problems noticed during diagnostic attempts are being carefully analyzed. According to information from intensive care units, patients with poor baseline lung function often do not tolerate ventilator disconnection during the apnea test (AT) despite previous preoxygenation and catheter O2 insufflation. Abortion of AT because of decrease of saturation as measured by pulse oximetry is quite common. To solve this problem, implementation of continuous positive airway pressure (CPAP) with 100% O2 was proposed as an option for newly developed guidelines. Before implementation of CPAP for AT we verified it by means of a multicenter trial in a group of 51 patients with various lung function. In one case, in a patient with baseline PaO2 of 83 mm Hg during ventilation with 100% oxygen, we used the CPAP option for AT and successfully completed BD diagnosis. In conclusion, ventilator-delivered CPAP for AT may be a valuable alternative to the classic oxygen insufflation method for the BD diagnosis procedure in patients with severe lung injury and poor baseline oxygenation.
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Apnea/diagnóstico , Muerte Encefálica/diagnóstico , Presión de las Vías Aéreas Positiva Contínua/métodos , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
A suspicion of brain death (BD) is the 1st step in the process of BD certification. Owing to its utmost importance, the process must yield an unequivocal answer so that the committee for the determination of BD has no doubts. We present a case of a patient with suspected BD, with a diagnosis of no intracranial flow in 4-vessel digital-subtraction angiography, who developed some reflexes just before clinical examination for BD assessment. The source of clinical findings was determined to be an extracranial blood supply, which enabled the preservation of trace lower brain stem functioning.
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Muerte Encefálica/diagnóstico , Infarto Encefálico/fisiopatología , Circulación Cerebrovascular , Anciano , Angiografía de Substracción Digital/métodos , Encéfalo/irrigación sanguínea , Muerte Encefálica/fisiopatología , Infarto Encefálico/complicaciones , Tronco Encefálico/fisiopatología , Angiografía Cerebral/métodos , Humanos , Masculino , Preservación Biológica , RespiraciónRESUMEN
BACKGROUND: The mitogen-activated protein kinases 1 and 2 (MEK1, MEK2) are fundamental partners in the RAS-RAF-MEK-ERK pathway that is involved in regulation of cell proliferation, differentiation and survival. Downregulation of the MEK cascades has been implicated in acquiring of the malignant phenotype in various cancers. Somatic mutations in MEK1 gene (substitutions K57N, Q56P, D67N) were described in <1 % of non-small cell lung cancer (NSCLC) and they were more commonly reported in adenocarcinoma patients with current or former smoking status. MATERIALS AND METHODS: In the following study, we assessed the MEK1 gene mutations in 145 FFPE tissue samples from central nervous system (CNS) metastases of NSCLC using HRM-PCR and ASP-qPCR techniques. The studied group was heterogeneous in terms of histopathology and smoking status. The prevalence of the MEK1 gene mutation was correlated with the occurrence of mutations in KRAS, EGFR, DDR2, PIK3CA, NRAS, HER2, AKT1 and PTEN genes. RESULTS: Using HRM and ASP-qPCR methods we identified one (0.7 %; 1/145) MEK1 substitution (Q56P) in CNS metastases of NSCLC. The mutation was identified in a single, 50-year-old, current smoking men with adenocarcinoma (1.25 %; 1/80 of all adenocarcinomas). CONCLUSIONS: According to the current knowledge, the incidence of MEK1 gene mutation in CNS metastatic lesion of NSCLC is the first such report worldwide. The analysis of gene profile in cancer patients may extend the scope of molecularly targeted therapies used both in patients with primary and metastatic tumors of NSCLC.
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Biomarcadores de Tumor/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Neoplasias del Sistema Nervioso Central/genética , Análisis Mutacional de ADN/métodos , Neoplasias Pulmonares/genética , MAP Quinasa Quinasa 1/genética , Mutación/genética , Adenocarcinoma/genética , Adenocarcinoma/patología , Carcinoma de Células Grandes/genética , Carcinoma de Células Grandes/patología , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Neoplasias del Sistema Nervioso Central/secundario , Detección Precoz del Cáncer/métodos , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/patología , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
The significant inversion symmetry breaking specific to wurtzite semiconductors, and the associated spontaneous electrical polarization, lead to outstanding features such as high density of carriers at the GaN/(Al,Ga)N interface-exploited in high-power/high-frequency electronics-and piezoelectric capabilities serving for nanodrives, sensors and energy harvesting devices. Here we show that the multifunctionality of nitride semiconductors encompasses also a magnetoelectric effect allowing to control the magnetization by an electric field. We first demonstrate that doping of GaN by Mn results in a semi-insulating material apt to sustain electric fields as high as 5 MV cm-1. Having such a material we find experimentally that the inverse piezoelectric effect controls the magnitude of the single-ion magnetic anisotropy specific to Mn3+ ions in GaN. The corresponding changes in the magnetization can be quantitatively described by a theory developed here.
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Multiple endocrine neoplasia type 1 (MEN1) is a rare but informative syndrome for endocrine tumorigenesis. Since its isolation, several groups have begun to determine the role of menin, the protein product of MEN1, in sporadic endocrine tumors as well as tumors of the MEN1 syndrome. Mutations of menin have been reported in more than 400 families and tumors, most of which are truncating mutations, thus supporting the function of menin as a tumor suppressor. The exact function of menin is unknown, but overexpression of menin inhibits proliferation of Ras-transformed NIH3T3 cells. Since menin interacts with proteins from both the TGF beta and AP-1 signaling pathways, perhaps its tumor suppressor function is related to these key cell growth pathways. In this review we will discuss the various clinical manifestations of MEN1 syndrome, potential mechanisms of MEN1 tumorigenesis, and mutations associated with MEN and sporadic endocrine tumors.
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Neoplasia Endocrina Múltiple Tipo 1/genética , Proteínas Proto-Oncogénicas , Secuencia de Aminoácidos , Animales , Expresión Génica , Humanos , Datos de Secuencia Molecular , Neoplasia Endocrina Múltiple Tipo 1/diagnóstico , Mutación , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Alineación de SecuenciaRESUMEN
The crystal structure of a Fab fragment (Fab3-2C2) of a monoclonal antibody raised against aromatase cytochrome P450 P450arom) has been determined at 3.0 A resolution. P450arom is a membrane bound enzyme responsible for the catalysis of indrogens to estrogens, the process of aromatization, and hence has been implicated in hormone-dependent breast cancer. The Fab fragment of MAb3-2C2 IgG suppresses P450arom activity in a dose dependent manner. The Fab3-2C2 molecule crystallizes n the space group P2(1)2(1)2(1) with a unit cell of a= 154.89 A, b = 73.51 A, and c= 36.90 A. The crystal structure consists of a light and a heavy chain in the asymmetric unit, each characterized by the greek-key antiparallel beta barrel folding seen in all Fab structures. The average elbow angle between the two domains is 143 degrees. Modeling of the interactions between the variable domains of the antibody and a known model of P450arom maps the epitope to a region of the enzyme that is consistent with the available biochemical data and the activity-suppressing function of the antibody. The epitope mapping result is further supported by the inability of MAb3-2C2 IgG to suppress the activity of, or to interact with placental porcine P450arom, which is 81% identical (86% similar) to human P450arom but has a few key substitutions in the putative epitope region.