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1.
Nat Mater ; 22(7): 848-852, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37106132

RESUMEN

Solid-state electrolytes overcome many challenges of present-day lithium ion batteries, such as safety hazards and dendrite formation1,2. However, detailed understanding of the involved lithium dynamics is missing due to a lack of in operando measurements with chemical and interfacial specificity. Here we investigate a prototypical solid-state electrolyte using linear and nonlinear extreme-ultraviolet spectroscopies. Leveraging the surface sensitivity of extreme-ultraviolet-second-harmonic-generation spectroscopy, we obtained a direct spectral signature of surface lithium ions, showing a distinct blueshift relative to bulk absorption spectra. First-principles simulations attributed the shift to transitions from the lithium 1 s state to hybridized Li-s/Ti-d orbitals at the surface. Our calculations further suggest a reduction in lithium interfacial mobility due to suppressed low-frequency rattling modes, which is the fundamental origin of the large interfacial resistance in this material. Our findings pave the way for new optimization strategies to develop these electrochemical devices via interfacial engineering of lithium ions.


Asunto(s)
Electrólitos , Litio , Suministros de Energía Eléctrica , Ingeniería , Programas Informáticos
2.
Acta Endocrinol (Buchar) ; 19(1): 31-35, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37601704

RESUMEN

Background: Insulin resistance (IR) is a component of type 2 diabetes and metabolic syndrome and it increases in the presence of chronic inflammation. Lately, "neutrophil-to-lymphocyte ratio" (NLR) has been used as an indicator of inflammation. This study evaluates the association between IR and NLR in obese women. Material and methods: Obese female patients who were followed up in a university hospital for the last two years were included in the study. Homeostasis model assessment of IR (HOMA-IR), C-peptide, NLR, bioelectrical impedance measurements of 83 patients were analyzed. Results: The C-peptide levels of our patients showed a highly significant correlation with HOMA-IR (p<0.001). A significant positive correlation was found between fasting plasma C-peptide levels and NLR (r=0.36 and p<0.003) in obese women. The increase in C-peptide levels had a significant effect on the increase in NLR (r2=0.31, p=0.002), however insulin had no similar effect on NLR (r2=0.01, p=0.544). Conclusion: Plasma C-peptide levels are better correlated with NLR compared to other parameters of IR. C-peptide may be used as an efficient laboratory marker with high relevance in IR and chronic inflammatory conditions in obese women.

3.
Phys Rev Lett ; 129(14): 147401, 2022 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-36240395

RESUMEN

High-harmonic generation (HHG) in solids has been touted as a way to probe ultrafast dynamics and crystal symmetries in condensed matter systems. Here, we investigate the polarization properties of high-order harmonics generated in monolayer MoS_{2}, as a function of crystal orientation relative to the mid-infrared laser field polarization. At several different laser wavelengths we experimentally observe a prominent angular shift of the parallel-polarized odd harmonics for energies above approximately 3.5 eV, and our calculations indicate that this shift originates in subtle differences in the recombination dipole strengths involving multiple conduction bands. This observation is material specific and is in addition to the angular dependence imposed by the dynamical symmetry properties of the crystal interacting with the laser field, and may pave the way for probing the vectorial character of multiband recombination dipoles.

4.
Nano Lett ; 21(14): 6095-6101, 2021 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-34264679

RESUMEN

The coexistence of ferroelectricity and metallicity seems paradoxical, since the itinerant electrons in metals should screen the long-range dipole interactions necessary for dipole ordering. The recent discovery of the polar metal LiOsO3 was therefore surprising [as discussed earlier in Y. Shi et al., Nat. Mater. 2013, 12, 1024]. It is thought that the coordination preferences of the Li play a key role in stabilizing the LiOsO3 polar metal phase, but an investigation from the combined viewpoints of core-state specificity and symmetry has yet to be done. Here, we apply the novel technique of extreme ultraviolet second harmonic generation (XUV-SHG) and find a sensitivity to the broken inversion symmetry in the polar metal phase of LiOsO3 with an enhanced feature above the Li K-edge that reflects the degree of Li atom displacement as corroborated by density functional theory calculations. These results pave the way for time-resolved probing of symmetry-breaking structural phase transitions on femtosecond time scales with element specificity.


Asunto(s)
Microscopía de Generación del Segundo Armónico , Metales , Análisis Espectral
5.
Phys Rev Lett ; 127(23): 237402, 2021 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-34936786

RESUMEN

Second harmonic generation (SHG) spectroscopy ubiquitously enables the investigation of surface chemistry, interfacial chemistry, as well as symmetry properties in solids. Polarization-resolved SHG spectroscopy in the visible to infrared regime is regularly used to investigate electronic and magnetic order through their angular anisotropies within the crystal structure. However, the increasing complexity of novel materials and emerging phenomena hampers the interpretation of experiments solely based on the investigation of hybridized valence states. Here, polarization-resolved SHG in the extreme ultraviolet (XUV-SHG) is demonstrated for the first time, enabling element-resolved angular anisotropy investigations. In noncentrosymmetric LiNbO_{3}, elemental contributions by lithium and niobium are clearly distinguished by energy dependent XUV-SHG measurements. This element-resolved and symmetry-sensitive experiment suggests that the displacement of Li ions in LiNbO_{3}, which is known to lead to ferroelectricity, is accompanied by distortions to the Nb ion environment that breaks the inversion symmetry of the NbO_{6} octahedron as well. Our simulations show that the measured second harmonic spectrum is consistent with Li ion displacements from the centrosymmetric position while the Nb─O bonds are elongated and contracted by displacements of the O atoms. In addition, the polarization-resolved measurement of XUV-SHG shows excellent agreement with numerical predictions based on dipole-induced SHG commonly used in the optical wavelengths. Our result constitutes the first verification of the dipole-based SHG model in the XUV regime. The findings of this work pave the way for future angle and time-resolved XUV-SHG studies with elemental specificity in condensed matter systems.

6.
Phys Rev Lett ; 127(9): 096801, 2021 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-34506179

RESUMEN

Charge transport processes at interfaces play a crucial role in many processes. Here, the first soft x-ray second harmonic generation (SXR SHG) interfacial spectrum of a buried interface (boron-Parylene N) is reported. SXR SHG shows distinct spectral features that are not observed in x-ray absorption spectra, demonstrating its extraordinary interfacial sensitivity. Comparison to electronic structure calculations indicates a boron-organic separation distance of 1.9 Å, with changes of less than 1 Å resulting in easily detectable SXR SHG spectral shifts (ca. hundreds of milli-electron volts).

7.
Org Biomol Chem ; 14(7): 2182-5, 2016 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-26790479

RESUMEN

We introduce a simple (1)H NMR method for quantification of the phospholipid content of liposomes. The method is validated by comparison with the established Stewart assay, which revealed significant uncertainties in phospholipid quantification of established liposome preparations used in supramolecular membrane transport assays.


Asunto(s)
Bioensayo/métodos , Liposomas/química , Fosfolípidos/química , Transporte Biológico , Límite de Detección , Espectroscopía de Resonancia Magnética , Factores de Tiempo
8.
Eur Rev Med Pharmacol Sci ; 28(1): 214-220, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38235872

RESUMEN

OBJECTIVE: Endometrium cancer (EC) is the most prevalent cancer affecting women in developed countries. There is debate about the need to perform lymphadenectomy in cases with a tumor diameter >2 cm. The aim of our study is to research the prediction of lymph node metastasis using tumor size in stage 1A endometrioid endometrium cancer (EEC). PATIENTS AND METHODS: The study enrolled cases operated in the clinic due to stage 1A EEC (FIGO 2009) from December 2010-2021. The correlations of age, age interval, parity, type of operation, tumor diameter, myometrial invasion, histological grade, and lymph node metastasis were statistically analyzed. The cut-off point for tumor size was determined with the ROC curve and Youden index. RESULTS: The study analyzed a total of 292 cases, and the mean age of cases was 62.3±10.0 years. Of the cases, 79.5% had histological grade 1, and 20.5% had grade 2. Myometrial invasion ≤50% was detected in 69.5%, and no myometrial invasion was detected in 30.5%. The mean tumor diameter was 34.0±18.0. Lymph node metastasis was identified in 6 cases (2.1%). Based on the tumor diameter cut-off value of 35 mm, sensitivity was 100%, and specificity was 50.3%. 116 cases with tumor diameter >35 mm and 176 with diameter ≤35 mm, and grade 2 histology and lymph node positivity were found statistically significant between these groups (respectively, p=0.012 and p=0.038). The lymph node metastasis risk was 0% in cases with tumor diameter ≤35 mm, while it was 5.2% in cases with tumor diameter >35 mm. CONCLUSIONS: The general approach in stage 1A EEC is not to perform lymphadenectomy. However, when the tumor diameter is noted, lymphadenectomy may be considered as the lymph node metastasis risk increases in cases with a tumor diameter of 35 mm or more. There is a need for more clinical studies on this topic.


Asunto(s)
Carcinoma Endometrioide , Neoplasias Endometriales , Femenino , Humanos , Persona de Mediana Edad , Anciano , Metástasis Linfática/patología , Carcinoma Endometrioide/cirugía , Carcinoma Endometrioide/patología , Neoplasias Endometriales/cirugía , Neoplasias Endometriales/patología , Escisión del Ganglio Linfático , Ganglios Linfáticos/cirugía , Ganglios Linfáticos/patología , Estadificación de Neoplasias , Estudios Retrospectivos
9.
Nat Commun ; 15(1): 2761, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38553469

RESUMEN

Devising an efficient exploration of the search space is one of the key challenges in the design of combinatorial optimization algorithms. Here, we introduce the Generator-Enhanced Optimization (GEO) strategy: a framework that leverages any generative model (classical, quantum, or quantum-inspired) to solve optimization problems. We focus on a quantum-inspired version of GEO relying on tensor-network Born machines, and referred to hereafter as TN-GEO. To illustrate our results, we run these benchmarks in the context of the canonical cardinality-constrained portfolio optimization problem by constructing instances from the S&P 500 and several other financial stock indexes, and demonstrate how the generalization capabilities of these quantum-inspired generative models can provide real value in the context of an industrial application. We also comprehensively compare state-of-the-art algorithms and show that TN-GEO is among the best; a remarkable outcome given the solvers used in the comparison have been fine-tuned for decades in this real-world industrial application. Also, a promising step toward a practical advantage with quantum-inspired models and, subsequently, with quantum generative models.

10.
Science ; 383(6678): 86-93, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38175897

RESUMEN

The metal-halide ionic octahedron is the optoelectronic unit for halide perovskites, and a crown ether-assisted supramolecular assembly approach can pack various ionic octahedra into tunable symmetries. In this work, we demonstrate near-unity photoluminescence quantum yield (PLQY) blue and green emission with the supramolecular assembly of hafnium (Hf) and zirconium (Zr) halide octahedral clusters. (18C6@K)2HfBr6 powders showed blue emission with a near-unity PLQY (96.2%), and green emission was also achieved with (18C6@K)2ZrCl4Br2 powders at a PLQY of 82.7%. These highly emissive powders feature facile low-temperature solution-based synthesis conditions and maintain high PLQY in solution-processable semiconductor inks under ambient conditions, and they were used in thin-film displays and emissive three-dimensional-printed architectures that exhibited high spatial resolution.

11.
Eur Rev Med Pharmacol Sci ; 27(21): 10396-10402, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37975362

RESUMEN

OBJECTIVE: To screen for geriatric syndromes in older in-hospital patients and investigate their relationship with mortality. PATIENTS AND METHODS: Demographic data, comorbidities, and medical history of the patients were recorded. Anthropometric measurements were obtained at 72 hours after hospital admission. The Mini Nutritional Assessment-Short Form, strength, assistance with walking, rising from a chair, climbing stairs, and falls (SARC-F) sarcopenia screening questionnaire, Katz Activities of Daily Living scale, Lawton-Brody instrumental activities of daily living scale, the fatigue, resistance, ambulation, illness, and loss of weight (FRAIL) scale and the Eating Assessment Test-10 (EAT-10) screening test were used to assess geriatric syndromes. All patients were evaluated for delirium, pain, falls, polypharmacy, sleep disorders, incontinence, and pressure injury by the same researcher. RESULTS: A total of 85 patients were included in the study. The mean age was 75±7 years (range: 66-97). During hospital follow-up, 15.3% (n=13) of the patients died and 84.7% (n=72) were discharged. The median length of stay was 19 days (range: 3-126 days). In the multivariate analysis, frailty (hazard ratio: 2.67, 95% CI: 1.41-5.06, p=0.003) was found to be associated with in-hospital mortality. CONCLUSIONS: Frailty is an independent risk factor for in-hospital mortality in older adults.


Asunto(s)
Fragilidad , Sarcopenia , Humanos , Anciano , Anciano de 80 o más Años , Fragilidad/diagnóstico , Anciano Frágil , Actividades Cotidianas , Mortalidad Hospitalaria , Evaluación Geriátrica , Sarcopenia/diagnóstico
12.
Eur Rev Med Pharmacol Sci ; 27(7): 2919-2926, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37070892

RESUMEN

OBJECTIVE: This study aims to determine the effect of frailty on thromboembolic events (TEE) and bleeding in older patients with non-valvular atrial fibrillation (AF). PATIENTS AND METHODS: Patients aged ≥65 years who were diagnosed as having non-valvular AF in a geriatric outpatient clinic between June 2015 and February 2021 were included in the study. Frailty, the risk of thrombosis secondary to AF, and the risk of bleeding as a complication of AF treatment were evaluated using the FRAIL scale, and CHA2DS2-VASc and HAS-BLED scores, respectively. RESULTS: Out of 83 patients included in the study, 72.3% were frail and 21.7% were pre-frail. TEE was observed in 14.5% (n=12) and bleeding was observed in 25.3% (n=21) of the patients. A total of 21 (25.3%) patients had a history of bleeding. There was no difference between the normal, pre-frail, and frail groups in terms of TEE and bleeding history (p=0.112 and p=0.571, respectively). In multivariate analysis, mortality decreased with the use of apixaban; frailty and malnutrition were found to increase mortality (p=0.014, p=0.023, and p=0.020, respectively). HAS-BLED-F score was obtained as a result of the sum of the patients' HAS-BLED and FRAIL scores to predict the bleeding risk. A HAS-BLED-F score of ≥6 predicted the risk of bleeding with 90.5% sensitivity and 40.3% specificity. CONCLUSIONS: Frailty is not associated with a statistically significant increase in the risk of thromboembolic events or bleeding in patients with non-valvular AF. HAS-BLED-F score can be used to better predict the risk of bleeding in frail patients.


Asunto(s)
Fibrilación Atrial , Fragilidad , Accidente Cerebrovascular , Tromboembolia , Humanos , Anciano , Fibrilación Atrial/complicaciones , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/diagnóstico , Fragilidad/diagnóstico , Fragilidad/complicaciones , Pacientes Ambulatorios , Vida Independiente , Anticoagulantes/efectos adversos , Medición de Riesgo , Hemorragia/inducido químicamente , Tromboembolia/etiología , Accidente Cerebrovascular/complicaciones , Factores de Riesgo
13.
J Eur Acad Dermatol Venereol ; 25(11): 1324-7, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21348898

RESUMEN

BACKGROUND: Pemphigus vulgaris (PV) is the most common clinical form of pemphigus that is characterized by easily ruptured or loose bulla formation on skin and/or mucosa. The frequency of the ear, nose and throat involvement of PV is not clearly defined. OBJECTIVES: To evaluate the frequency of ear, nose and throat (ENT) involvement in patients suffering from PV who had been recently diagnosed or exacerbated under follow up and to determine the association with ENT symptoms, clinical involvement, severity and duration of pemphigus vulgaris. MATERIALS AND METHODS: The study group included a total of 38 PV patients comprising 24 new patients and 14 patients who showed exacerbations while on complete remission or under treatment. All patients were asked about ENT symptoms and endoscopic examination were performed to evaluate the presence of nasal, pharynx, larynx and ear involvement. RESULTS: Of the 38 patients, 33 (87%) had active PV lesions on endoscopic evaluation. Twenty-five patients (66%) had lesions on pharynx, twenty-one (55%) on larynx, twenty-nine (76%) on nasal mucosa and four (10%) on the ear mucosa. ENT involvement was not associated with the severity and the clinical involvement of the disease. Pharyngeal and nasal involvement was significantly associated with symptoms, while laryngeal and ear involvement was not found to be significantly associated with symptoms. Nasal and ear involvement was not associated with the duration of the disease while pharyngeal and laryngeal involvement favored newly diagnosed patients. CONCLUSIONS: Our results revealed that high number of patients with PV may present with active ENT lesions, furthermore patients with ear, nose and throat involvement may be asymptomatic and active lesions may be found in patients without any ENT symptoms. Therefore it should be considered that to understand the real extent of PV involvement, endoscopic ENT evaluation should be performed in patients with or without symptoms.


Asunto(s)
Oído/fisiopatología , Nariz/fisiopatología , Pénfigo/fisiopatología , Faringe/fisiopatología , Índice de Severidad de la Enfermedad , Humanos , Fenotipo
14.
Artículo en Inglés, Español | MEDLINE | ID: mdl-34172427

RESUMEN

OBJECTIVE: Primary hyperparathyroidism (PHPT) is one of the most frequent endocrine diseases. Most of the patients with PHPT are asymptomatic, and only 20% of them become symptomatic with increasing levels of calcium. It has been reported that normocalcemic primary hyperparathyroidism (NPHPT) may be the incipient period of PHPT where calcium (Ca) levels are in normal range, and it may advance to overt PHPT. Early diagnosis of PHPT is important in order to prevent its complications. In this retrospective study, we aimed to evaluate the role of 99mTc-MIBI parathyroid scintigraphy on lesion detection in patients with NPHPT. MATERIAL AND METHODS: The parathyroid scintigraphy database was reviewed retrospectively in patients with PHPT. 117 patients who underwent 99mTc-MIBI scintigraphy were recruited to the study. Serum calcium level above 10.5mg/dl was considered as hypercalcemia. RESULTS: A total of 117 patients' (female/male:98/19) mean serum PTH levels (mean±SD) were 149±97 pg/ml in normocalcemic group (Ca:9.6±0.6mg/dL, n:38) and 189±135 pg/ml in hypercalcemic group (Ca:11.4±0.6mg/dL, n:79) (p:0.072). The sex and ages were not different between the scintigraphy positive and negative groups, but the lesion detection rates with parathyroid scintigraphy were 42% in normocalcemic group and 81% in hypercalcemic group (p<0.0001). CONCLUSIONS: Several factors including serum Ca, the imaging protocol, existence of multiglandular disease, the size and MIBI biokinetics of the adenoma may influence lesion detectability in parathyroid scintigraphy. Although high serum Ca level is an important parameter in predicting its success, parathyroid scintigraphy remains a valuable diagnostic method even in patients with NPHPT.

15.
J Eur Acad Dermatol Venereol ; 24(7): 840-3, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19925600

RESUMEN

BACKGROUND: Despite its nature as a systemic vasculitis, renal involvement is known to occur infrequently in Behçet's Disease (BD). OBJECTIVES: Our aim was to investigate proteinuria, microhematuria and microalbuminuria in 24-h urine and evaluate subclinical or symptomatic renal involvement in BD patients. METHODS: Two hundred and eleven patients who fulfilled the International Behçet's Disease criteria were included in the study. After urine analysis, five of 12 patients who were found to have proteinuria underwent renal biopsy, while 199 patients without proteinuria were investigated for microalbuminuria (MA). RESULTS: A total of 34 (16.1%) patients were found to have renal involvement including 22 (11.1%) with MA and 12 with proteinuria (5.6%). Renal biopsies resulted as focal glomerulosclerosis in three, membranous glomerulosclerosis in one and secondary amyloidosis in two patients. Neurological involvement was found to be significantly more prevalent in patients with MA (P < 0.01). Neurological involvement and duration of disease (> or = 10 years) was found to increase the risk for MA by 21.75-fold and 5.03-fold, respectively. Though age over 40 years, thrombophlebitis, HLA B51 haplotype and ophthalmological involvement were not found to be significantly associated with MA; these parameters increased the risk for MA. CONCLUSIONS: Renal involvement may be more prevalent in BD than it has been recognized; it usually presents with asymptomatic microhematuria, proteinuria and/or microalbuminuria; therefore clinicians must check 24-h urine for the presence of proteinuria, microhematuria and microalbuminuria; especially in patients who are aged over 40 years, have a longer duration of the disease and multisystem involvement.


Asunto(s)
Albuminuria/fisiopatología , Síndrome de Behçet/orina , Biomarcadores/orina , Enfermedades Renales/orina , Adolescente , Adulto , Anciano , Síndrome de Behçet/patología , Síndrome de Behçet/fisiopatología , Biopsia , Femenino , Humanos , Enfermedades Renales/patología , Enfermedades Renales/fisiopatología , Masculino , Persona de Mediana Edad , Análisis Multivariante , Adulto Joven
16.
J Hazard Mater ; 152(1): 415-22, 2008 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-17692458

RESUMEN

In this study, the removal of boric acid from aqueous solution by activated carbon impregnated with salicylic acid was studied in batch system. pH, adsorbent amount, initial boron concentration, temperature, shaking rate and salicylic acid film thickness were chosen as parameters. Boron removal efficiencies increased with increasing adsorbent amount, temperature and pH, decreasing initial boron concentration. As thickness of salicylic acid film on activated carbon becomes thin up to 0.088nm, the efficiency increased, and then, the efficiency decreased with becoming thinner than 0.088nm of salicylic acid film. Shaking rate was no effect on removal efficiency. In result, it was determined that the use of salicylic acid as an impregnant for activated carbon led to the increase of the amount of boron adsorbed. A lactone ring, being the most appropriate conformation, forms between boric acid and -COOH and -OH groups of salicylic acid.


Asunto(s)
Boro/aislamiento & purificación , Carbono/química , Ácido Salicílico/química , Concentración de Iones de Hidrógeno , Soluciones , Agua
17.
J Clin Pathol ; 58(1): 87-9, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15623491

RESUMEN

A 36 year old pregnant woman was admitted to hospital complaining of an enlarging mass in her left breast. Histopathological examination of the mastectomy specimen revealed a high grade infiltrating ductal adenocarcinoma intermixed with a lactating adenoma. Lactating adenomas are rare entities but are the most common masses that occur during pregnancy. Although they are not thought to carry an increased risk of cancer there are two other case reports in the literature of a lactating adenoma associated with an infiltrating carcinoma. In this case, areas where the lactating adenoma and the infiltrating carcinoma were intermixed could be identified. This case could simply be a collision tumour, although the possibility of an invasive carcinoma arising within a lactating adenoma cannot be ruled out. Because of the relative lack of experience with lactating adenomas, the question of an increased association with carcinoma development remains unclear.


Asunto(s)
Adenoma/patología , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/patología , Neoplasias Primarias Múltiples/patología , Complicaciones Neoplásicas del Embarazo/patología , Adulto , Femenino , Humanos , Lactancia , Embarazo
18.
Am J Med Genet ; 75(3): 252-5, 1998 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-9475591

RESUMEN

We have studied an infant with cloverleaf skull, proptosis, radioulnar synostosis and broad thumbs and great toes diagnosed as Pfeiffer syndrome type 2. However, there were many overlapping findings with Antley-Bixler syndrome. The patient was found to have a G to T mutation in codon 290 exon 7 of the FGFR2 gene leading to a substitution of a cys for the normal trp at this locus. This is the third mutation characterized at this codon; therefore, this locus appears to be a mutational hotspot in the gene. However, the other known mutations lead to a milder, Crouzon-like phenotype. The introduction of an additional cys into a region characterized by immunoglobulin-type loops maintained by cys S-S crosslinking may provide an explanation for the severity of the clinical findings of this child.


Asunto(s)
Acrocefalosindactilia/genética , Codón , Disostosis Craneofacial/genética , Mutación , Proteínas Tirosina Quinasas Receptoras/genética , Receptores de Factores de Crecimiento de Fibroblastos/genética , Secuencia de Aminoácidos , Cisteína/genética , Exones , Femenino , Humanos , Recién Nacido , Datos de Secuencia Molecular , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos , Triptófano/genética
20.
Eur J Ophthalmol ; 6(2): 150-4, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8823588

RESUMEN

Frontalis suspension procedure using a Mersilene mesh sling was performed on 23 ptotic eyelids of 22 patients (age range 3 to 35 years) with poor or absent levator function. The surgical technique used was a modified Fox's method. The mean palpebral fissure height was 3.1 mm preoperatively and increased to 8.0 mm after the operation. No serious complication was seen postoperatively and during an average follow-up of 25 months. In one case with a cosmetically inadequate result, the upper third of the initially implanted Mersilene mesh was removed during reoperation and histological examination of the specimen revealed fibrovascular tissue invasion through the mesh fibres. Mersilene mesh appears to be an effective and safe alternative sling material for brow suspension surgery, giving good permanent results for cases in which autogenous fascia lata was inappropriate.


Asunto(s)
Blefaroptosis/cirugía , Tereftalatos Polietilenos , Procedimientos Quirúrgicos Operativos/métodos , Adolescente , Adulto , Materiales Biocompatibles , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Masculino , Complicaciones Posoperatorias/patología , Estudios Retrospectivos , Resultado del Tratamiento
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