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1.
Eur Rev Med Pharmacol Sci ; 27(7): 3181-3190, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37070921

RESUMEN

OBJECTIVE: The aim of the present study was to assess the safety and efficacy of Diclofenac sodium (DS) 140 mg medicated plaster vs. Diclofenac epolamine (DIEP) 180 mg medicated plaster and placebo plaster, for the treatment of painful disease due to traumatic events of the limbs. PATIENTS AND METHODS: This was a multicenter, phase III study involving 214 patients, aged 18-65 years, affected by painful conditions due to soft tissue injuries. Patients were randomized to DS, DIEP or placebo arms and treated with once-daily application of the plaster for a total treatment period of 7 days. The primary objective was first to demonstrate the non-inferior efficacy of the DS treatment when compared to the reference DIEP treatment and second that both, test and reference treatments, were superior with respect to placebo. The secondary objectives included the evaluation of efficacy, adhesion, safety, and local tolerability of DS in comparison to both DIEP and placebo. RESULTS: The mean visual analog scale (VAS) score decrease for pain at rest was higher in the DS (-17.65 mm) and the DIEP group (-17.5 mm) than in the placebo (-11.3 mm). Both active formulation plasters were associated with a statistically significant pain reduction compared to placebo. No statistically significant differences were observed between DIEP and DS plasters efficacy in relieving pain. Secondary endpoint evaluations supported the primary efficacy results. No serious adverse events (SAEs) were registered, and the most commonly detected adverse events were skin reactions at the application site. CONCLUSIONS: The results showed that both the DS 140 mg plaster and the reference DIEP 180 mg plaster are effective in relieving pain and present a good safety profile.


Asunto(s)
Dolor Agudo , Traumatismos de los Tejidos Blandos , Humanos , Diclofenaco/efectos adversos , Traumatismos de los Tejidos Blandos/inducido químicamente , Traumatismos de los Tejidos Blandos/complicaciones , Método Doble Ciego , Antiinflamatorios no Esteroideos/efectos adversos , Resultado del Tratamiento
2.
Nano Lett ; 22(21): 8541-8549, 2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36287197

RESUMEN

Addressable quantum states well isolated from the environment are of considerable interest for quantum information science and technology. Carbon nanotubes are an appealing system, since a perfect crystal can be grown without any missing atoms and its cylindrical structure prevents ill-defined atomic arrangement at the surface. Here, we develop a reliable process to fabricate compact multielectrode circuits that can sustain the harsh conditions of the nanotube growth. Nanotubes are suspended over multiple gate electrodes, which are themselves structured over narrow dielectric ridges to reduce the effect of the charge fluctuators of the substrate. We measure high-quality double- and triple-quantum dot charge stability diagrams. Transport measurements through the triple-quantum dot indicate long-range tunneling of single electrons between the left and right quantum dots. This work paves the way to the realization of a new generation of condensed-matter devices in an ultraclean environment, including spin qubits, mechanical qubits, and quantum simulators.

3.
AJNR Am J Neuroradiol ; 42(11): 2086-2093, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34503947

RESUMEN

BACKGROUND AND PURPOSE: On the basis of a single multidynamic multiecho sequence acquisition, SyMRI generates a variety of quantitative image data that can characterize tissue-specific properties. The aim of this retrospective study was to evaluate the feasibility of SyMRI for the qualitative and quantitative assessment of fetal brain maturation. MATERIALS AND METHODS: In 52 fetuses, multidynamic multiecho sequence acquisitions were available. SyMRI was used to perform multidynamic multiecho-based postprocessing. Fetal brain maturity was scored qualitatively on the basis of SyMRI-generated MR imaging data. The results were compared with conventionally acquired T1-weighted/T2-weighted contrasts as a standard of reference. Myelin-related changes in T1-/T2-relaxation time/relaxation rate, proton density, and MR imaging signal intensity of the developing fetal brain stem were measured. A Pearson correlation analysis was used to detect correlations between the following: 1) the gestational age at MR imaging and the fetal brain maturity score, and 2) the gestational age at MR imaging and the quantitative measurements. RESULTS: SyMRI provided images of sufficient quality in 12/52 (23.08%) (range, 23 + 6-34 + 0) fetal multidynamic multiecho sequence acquisitions. The fetal brain maturity score positively correlated with gestational age at MR imaging (SyMRI: r = 0.915, P < .001/standard of reference: r = 0.966, P < .001). Myelination-related changes in the T2 relaxation time/T2 relaxation rate of the medulla oblongata significantly correlated with gestational age at MR imaging (T2-relaxation time: r = -0.739, P = .006/T2-relaxation rate: r = 0.790, P = .002). CONCLUSIONS: Fetal motion limits the applicability of multidynamic multiecho-based postprocessing. However, SyMRI-generated image data of sufficient quality enable the qualitative assessment of maturity-related changes of the fetal brain. In addition, quantitative T2 relaxation time/T2 relaxation rate mapping characterizes myelin-related changes of the brain stem prenatally. This approach, if successful, opens novel possibilities for the evaluation of structural and biochemical aspects of fetal brain maturation.


Asunto(s)
Encéfalo , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Medios de Contraste , Humanos , Estudios Retrospectivos
4.
Phys Rev Lett ; 126(17): 175502, 2021 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-33988423

RESUMEN

We report the first study on the thermal behavior of the stiffness of individual carbon nanotubes, which is achieved by measuring the resonance frequency of their fundamental mechanical bending modes. We observe a reduction of the Young's modulus over a large temperature range with a slope -(173±65) ppm/K in its relative shift. These findings are reproduced by two different theoretical models based on the thermal dynamics of the lattice. These results reveal how the measured fundamental bending modes depend on the phonons in the nanotube via the Young's modulus. An alternative description based on the coupling between the measured mechanical modes and the phonon thermal bath in the Akhiezer limit is discussed.

5.
Ultrasound Obstet Gynecol ; 58(1): 34-41, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-32484578

RESUMEN

OBJECTIVES: Corpus callosal agenesis (CCA) is one of the most common brain malformations and is generally associated with a good outcome when isolated. However, up to 25% of patients are at risk of neurodevelopmental delay, which currently available clinical and imaging parameters are inadequate to predict. The objectives of this study were to apply and validate a fetal magnetic resonance imaging (MRI) anatomical scoring system in a cohort of fetuses with isolated CCA and to evaluate the correlation with postnatal neurodevelopmental outcome. METHODS: This was a retrospective cohort study of cases of prenatally diagnosed isolated CCA (as determined on ultrasound and MRI), with normal karyotype and with known postnatal neurodevelopmental outcome assessed by standardized testing. A fetal brain MRI anatomical scoring system based on seven categories (gyration, opercularization, temporal lobe symmetry, lamination, hippocampal position, basal ganglia and ventricular size) was developed and applied to the cohort; a total score of 0-11 points could be given, with a score of 0 representing normal anatomy. Images were scored independently by two neuroradiologists blinded to the outcome. For the purpose of assessing the correlation between fetal MRI score and neurodevelopmental outcome, neurodevelopmental test results were scored as follows: 0, 'below average' (poor outcome); 1, 'average'; and 2, 'above average' (good outcome). Spearman's rank coefficient was used to assess correlation, and inter-rater agreement in the assessment of fetal MRI score was calculated. RESULTS: Twenty-one children (nine females (42.9%)) fulfilled the inclusion criteria. Thirty-seven fetal MRI examinations were evaluated. Mean gestational age was 28.3 ± 4.7 weeks (range, 20-38 weeks). All fetuses were delivered after 35 weeks' gestation with no perinatal complications. Fetal MRI scores ranged from 0 to 6 points, with a median of 3 points. Inter-rater agreement in fetal MRI score assessment was excellent (intraclass correlation coefficient, 0.959 (95% CI, 0.921-0.979)). Neurodevelopmental evaluation was performed on average at 2.6 ± 1.46 years (range, 0.5-5.8 years). There was a significant negative correlation between fetal MRI score and neurodevelopmental outcome score in the three areas tested: cognitive (ρ = -0.559, P < 0.0001); motor (ρ = -0.414, P = 0.012) and language (ρ = -0.565, P < 0.0001) skills. Using fetal MRI score cut-offs of ≤ 3 (good outcome) and ≥ 4 points (high risk for poor outcome), the correct prognosis could be determined in 20/21 (95.2% (95% CI, 77.3-99.2%)) cases. CONCLUSION: By assessing structural features of the fetal brain on MRI, it may be possible to better stratify prenatally the risk of poor neurodevelopmental outcome in CCA patients. © 2020 Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Agenesia del Cuerpo Calloso/diagnóstico por imagen , Feto/diagnóstico por imagen , Imagen por Resonancia Magnética/estadística & datos numéricos , Trastornos del Neurodesarrollo/diagnóstico por imagen , Agenesia del Cuerpo Calloso/complicaciones , Agenesia del Cuerpo Calloso/embriología , Encéfalo/diagnóstico por imagen , Encéfalo/embriología , Preescolar , Cuerpo Calloso/diagnóstico por imagen , Cuerpo Calloso/embriología , Cuerpo Calloso/fisiopatología , Femenino , Feto/embriología , Edad Gestacional , Humanos , Lactante , Recién Nacido , Imagen por Resonancia Magnética/métodos , Masculino , Trastornos del Neurodesarrollo/etiología , Valor Predictivo de las Pruebas , Embarazo , Pronóstico , Reproducibilidad de los Resultados , Estudios Retrospectivos , Medición de Riesgo , Estadísticas no Paramétricas , Ultrasonografía Prenatal
6.
Eur J Radiol ; 134: 109457, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33302027

RESUMEN

OBJECTIVES: Fetal magnetic resonance imaging (MRI) plays an increasingly important role in the prenatal diagnosis of gastrointestinal abnormalities. During gestation, the bowel develops T1-weighted hyperintensity due to meconium formation. Currently used T1-weighted sequences are performed in maternal breath-hold (BH) technique, which may take up to 20 s. The free-breathing (FB) T1-weighted 3D radial VIBE (volumetric interpolated breath-hold examination) sequence requires no breath-hold, improving patient comfort. This study aimed to address how well the FB acquisition technique can visualize large bowel structures compared to the routinely performed breath-hold sequence. METHODS: Forty-seven fetal MRI studies between 21 and 36 weeks of gestation without abdominal pathologies on prenatal MRI and ultrasound were included. All fetal scans were performed using a Philips Ingenia 1.5 T MRI. Coronal T1-weighted BH and FB sequences without fat suppression were compared. The following acquisition parameters were used (T1, FB): resolution 1.137 mm, 1.004 mm; matrix size 288 × 288, 448 × 448; FOV 328 mm, 450 mm; TR 81-132 ms, 3.47 ms; TE 4.6 ms, 1.47 ms. Due to the necessity of the breath-hold the duration of the sequence could not exceed 20 s (mean duration of the T1-weighted BH sequence 15.17 s, and mean duration of the FB sequence 26.42 s). In all examined fetuses the following structures were evaluated with respect to their visibility (0-not visible, 1-partially visible, 2-clearly visible): rectum, sigmoid, descending, transverse and ascending colon, cecum. Furthermore, motion artifacts were assessed (0-none, 1-intermediate, 2-severe motion artifacts), and the signal intensity (SI) ratio between maternal fat and fetal rectum SI was calculated. RESULTS: No significant differences in the visibility of sigmoid and colon between BH and FB were detected, only the cecum could be seen slightly better (in 29.8 % of cases) using BH technique. Motion artifacts were similar between BH and FB. There was a non-significant SI difference (p = 0.68) in the rectum, with a higher SI in the BH sequence. CONCLUSIONS: The FB acquisition technique compared to T1 using BH is equal regarding visibility of bowel structures and artifacts. Due to non-inferiority to the BH technique, the FB sequence is a good alternative in cases where BH cannot be performed. As the FB sequence further allows for thinner slices with a good signal, even small bowel loops may be visualized.


Asunto(s)
Contencion de la Respiración , Aumento de la Imagen , Artefactos , Colon/diagnóstico por imagen , Feto/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Respiración , Estudios Retrospectivos
7.
Ultrasound Obstet Gynecol ; 58(2): 254-263, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-32730667

RESUMEN

OBJECTIVES: To characterize spatiotemporal growth differences of prenatal brainstem substructures and cerebellum, using linear biometry and planimetry on fetal magnetic resonance imaging (MRI). METHODS: In this retrospective study, we included fetuses with normal brain and a precise midsagittal T2-weighted brain MRI sequence obtained between May 2003 and April 2019. The cross-sectional area, rostrocaudal diameter and anteroposterior diameter of the midbrain, pons (basis pontis and pontine tegmentum), medulla oblongata and cerebellar vermis, as well as the transverse cerebellar diameter, were quantified by a single observer. The diameters were also assessed by a second observer to test inter-rater variability. RESULTS: We included 161 fetuses with normal brain and a precise midsagittal MRI sequence, examined at a mean ± SD gestational age of 25.7 ± 5.4 (range, 14 + 0 to 39 + 2) weeks. All substructures of the fetal brainstem and the cerebellum could be measured consistently (mean ± SD interobserver intraclass correlation coefficient, 0.933 ± 0.065). We provide reference data for diameters and areas of the brainstem and cerebellum in the second and third trimesters. There was a significant quadratic relationship between vermian area and gestational age, and all other measured parameters showed a significant linear growth pattern within the observed period (P < 0.001). A significant change in the relative proportions of the brainstem substructures occurred between the beginning of the second trimester and the end of the third trimester, with an increase in the area of the pons (P < 0.001) and a decrease in that of the midbrain (P < 0.001), relative to the total brainstem area. CONCLUSIONS: The substructures of the fetal brainstem follow a distinct spatiotemporal growth pattern, characterized by a relative increase in the pons and decrease in the midbrain, between 15 and 40 weeks of gestation. Caution is needed when interpreting fetal brainstem appearance during the early second trimester, as the brainstem proportions differ significantly from the adult morphology. The reference data provided herein should help to increase diagnostic accuracy in detecting disorders of defective hindbrain segmentation. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Tronco Encefálico/diagnóstico por imagen , Feto/diagnóstico por imagen , Diagnóstico Prenatal , Tronco Encefálico/crecimiento & desarrollo , Femenino , Edad Gestacional , Humanos , Imagen por Resonancia Magnética , Embarazo , Valores de Referencia , Estudios Retrospectivos
8.
Sci Rep ; 10(1): 13795, 2020 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-32782328

RESUMEN

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

9.
Breast Cancer ; 27(6): 1107-1113, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32488732

RESUMEN

PURPOSE: When ipsilateral breast-tumor recurrence (IBTR) following breast-conserving surgery (BCS) occurs, the cure of a potentially life-threatening disease is the main goal. If, however, this is diagnosed early, prognosis is still good and patient-reported outcomes become more important. Despite the fact that many patients would prefer a further BCS, international breast cancer guidelines still recommend mastectomy, mainly because previous radiation implies limited options. Our comparative study evaluates the long-term quality-of-life and outcome in patients with IBTR who received BCS plus intraoperative radiotherapy (IORT) versus mastectomy. METHODS: Patients with IBTR were retrospectively divided into three groups according to the local treatment: group 1 (n = 26) was treated with BCS + IORT; group 2 (n = 35) received a standard mastectomy; group 3 (n = 52) had a mastectomy with subsequent reconstruction. Outcomes were analyzed after a mean follow-up of 5 years after IBTR. Quality-of-life was evaluated by the validated questionnaire BREAST-Q in 50 patients who fulfilled the inclusion criteria. RESULTS: Quality-of-life scores varied within the groups, ranging from 51.4 to 91.3 (out of 100 points). We observed satisfactory scores in all items, with no statistical difference within the groups. Disease-free survival of all groups did not statistically differ, and overall mortality was very low (0.9%). The postinterventional complication rate was lower after BCS (19.2% versus 34.3% after mastectomy and 30.8% after mastectomy with reconstruction). CONCLUSION: For patients with previous surgery and radiation who demand a second BCS in the recurrent situation, this surgical technique can be offered in combination with IORT. Our long-term results imply oncological safety, lower complication rate, and good patient satisfaction.


Asunto(s)
Neoplasias de la Mama/terapia , Mastectomía Segmentaria/psicología , Mastectomía/psicología , Recurrencia Local de Neoplasia/terapia , Complicaciones Posoperatorias/epidemiología , Anciano , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Supervivencia sin Enfermedad , Femenino , Humanos , Mamoplastia/efectos adversos , Mastectomía/efectos adversos , Mastectomía/estadística & datos numéricos , Mastectomía Segmentaria/efectos adversos , Mastectomía Segmentaria/estadística & datos numéricos , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Recurrencia Local de Neoplasia/patología , Prioridad del Paciente/estadística & datos numéricos , Satisfacción del Paciente/estadística & datos numéricos , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/psicología , Pronóstico , Radioterapia Adyuvante/psicología , Radioterapia Adyuvante/estadística & datos numéricos , Estudios Retrospectivos
10.
Ultrasound Obstet Gynecol ; 56(1): 78-85, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31595598

RESUMEN

OBJECTIVE: Normal cognitive development usually requires a structurally intact and complete cerebellar vermis. The aim of this study was to evaluate whether quantification by fetal magnetic resonance imaging (MRI) of vermis- and brainstem-specific imaging markers improves the definition of cystic posterior fossa malformations (cPFM). METHODS: Fetuses diagnosed with cPFM that had an available midsagittal plane on T2-weighted MRI were identified retrospectively and compared with gestational-age (GA) matched brain-normal controls. Fetuses with cPFM were assigned to three groups, according to standard criteria (vermian size and brainstem-vermis (BV) angle): normal vermian area and BV angle < 25° (Group 1); reduced vermian area and/or BV angle of 25-45° (Group 2); and reduced vermian area and BV angle > 45° (Group 3; Dandy-Walker malformation (DWM) group). The number of differentiable vermian lobules and the areas of the vermis, mesencephalon, pons and medulla oblongata were quantified, correlated with and controlled for GA, and compared between the study groups. RESULTS: In total, 142 cases of cPFM were included, with a mean GA of 25.20 ± 5.11 weeks. Cases comprised Blake's pouch cyst (n = 46), arachnoid cyst (n = 12), inferior vermian hypoplasia (n = 5), megacisterna magna (n = 35) and classic DWM (n = 44). In the control group, 148 fetuses were included, with a mean GA of 25.26 ± 4.12 weeks. All quantified areas and the number of differentiable vermian lobules had a significant positive correlation with GA. The number of vermian lobules and the areas of all quantified regions, except for that of the medulla oblongata, differed significantly between the study groups (P ≤ 0.015 for all). The control group had the highest number of differentiable vermian lobules and the DWM group had the lowest (P < 0.01). CONCLUSIONS: Prenatal MRI assessment of vermian lobules is a useful addition to standard neuroradiological and neurosonographic techniques. The quantification of vermian lobules using fetal MRI allows further differentiation of cPFM into subgroups and thereby improves the classification of hindbrain malformations. © 2019 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Síndrome de Dandy-Walker/diagnóstico por imagen , Malformaciones del Sistema Nervioso/diagnóstico por imagen , Adulto , Fosa Craneal Posterior/anomalías , Fosa Craneal Posterior/diagnóstico por imagen , Femenino , Edad Gestacional , Humanos , Recién Nacido , Imagen por Resonancia Magnética , Valor Predictivo de las Pruebas , Embarazo , Diagnóstico Prenatal
11.
Biomech Model Mechanobiol ; 19(3): 823-840, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31782029

RESUMEN

A popular hypothesis explains the mechanosensitivity of bone due to osteocytes sensing the load-induced flow of interstitial fluid squeezed through the lacunocanalicular network (LCN). However, the way in which the intricate structure of the LCN influences fluid flow through the network is largely unexplored. We therefore aimed to quantify fluid flow through real LCNs from human osteons using a combination of experimental and computational techniques. Bone samples were stained with rhodamine to image the LCN with 3D confocal microscopy. Image analysis was then performed to convert image stacks into mathematical network structures, in order to estimate the intrinsic permeability of the osteons as well as the load-induced fluid flow using hydraulic circuit theory. Fluid flow was studied in both ordinary osteons with a rather homogeneous LCN as well as a frequent subtype of osteons-so-called osteon-in-osteons-which are characterized by a ring-like zone of low network connectivity between the inner and the outer parts of these osteons. We analyzed 8 ordinary osteons and 9 osteon-in-osteons from the femur midshaft of a 57-year-old woman without any known disease. While the intrinsic permeability was 2.7 times smaller in osteon-in-osteons compared to ordinary osteons, the load-induced fluid velocity was 2.3 times higher. This increased fluid velocity in osteon-in-osteons can be explained by the longer path length, needed to cross the osteon from the cement line to the Haversian canal, including more fluid-filled lacunae and canaliculi. This explanation was corroborated by the observation that a purely structural parameter-the mean path length to the Haversian canal-is an excellent predictor for the average fluid flow velocity. We conclude that osteon-in-osteons may be particularly significant contributors to the mechanosensitivity of cortical bone, due to the higher fluid flow in this type of osteons.


Asunto(s)
Osteón/fisiología , Imagenología Tridimensional , Microscopía Confocal/métodos , Osteocitos/metabolismo , Huesos/metabolismo , Femenino , Fémur/fisiología , Humanos , Procesamiento de Imagen Asistido por Computador , Persona de Mediana Edad , Modelos Teóricos , Permeabilidad , Rodaminas/química
12.
Hand Surg Rehabil ; 38(6): 364-368, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31563711

RESUMEN

Morbid obesity is associated with reduced health-related quality of life (HRQOL), increased morbidity and mortality. Little is known about the correlation between obesity and complex distal radius fractures (DRF). The purpose of this study was to examine the effect of being overweight on postoperative HRQOL after surgically treated intra-articular DRF. Fifty-three patients were included in this retrospective study with 7 years' mean follow-up (mean 7.2±0.4, range 6.4-7.9 years) after volar plating of an intra-articular DRF (AO-type C). All patients were categorized by their body mass index (BMI) into two study groups: group 1 (normal weight) with a BMI<25 (n=24); group 2 (obese) with a BMI≥25 (n=29). HRQOL and functional outcomes were assessed through range of motion (ROM) and four different scores - the 36-item short form health survey (SF-36), the disability of arm and shoulder score (DASH), the Gartland and Werley score and the Castaing score - along with X-rays to measure volar tilt, radial inclination, radial length and articular congruity. All HRQOL assessments and clinical outcomes were correlated to BMI by comparing group 1 versus group 2. There was no difference in terms of postoperative ROM. The group of normal weight patients achieved slightly better but non-significant results for the Gartland and Werley score. No differences were seen in the DASH score or SF-36. There were also no differences regarding the Castaing score. Overall, normal and obese patients had no significant differences their HRQOL and functionality after volar plating of DRF.


Asunto(s)
Índice de Masa Corporal , Fracturas Intraarticulares/cirugía , Calidad de Vida , Fracturas del Radio/cirugía , Placas Óseas , Evaluación de la Discapacidad , Femenino , Estudios de Seguimiento , Fijación Interna de Fracturas , Humanos , Masculino , Persona de Mediana Edad , Rango del Movimiento Articular , Estudios Retrospectivos
13.
Nano Lett ; 19(10): 6987-6992, 2019 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-31478676

RESUMEN

We report on a nanomechanical engineering method to monitor matter growth in real time via e-beam electromechanical coupling. This method relies on the exceptional mass sensing capabilities of nanomechanical resonators. Focused electron beam-induced deposition (FEBID) is employed to selectively grow platinum particles at the free end of singly clamped nanotube cantilevers. The electron beam has two functions: it allows both to grow material on the nanotube and to track in real time the deposited mass by probing the noise-driven mechanical resonance of the nanotube. On the one hand, this detection method is highly effective as it can resolve mass deposition with a resolution in the zeptogram range; on the other hand, this method is simple to use and readily available to a wide range of potential users because it can be operated in existing commercial FEBID systems without making any modification. The presented method allows one to engineer hybrid nanomechanical resonators with precisely tailored functionalities. It also appears as a new tool for studying the growth dynamics of ultrathin nanostructures, opening new opportunities for investigating so far out-of-reach physics of FEBID and related methods.

14.
Ultrasound Obstet Gynecol ; 53(6): 816-826, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30985045

RESUMEN

OBJECTIVE: To assess the clinical feasibility and validity of fetal magnetic resonance imaging (MRI)-based three-dimensional (3D) reconstruction to locate, classify and quantify diaphragmatic defects in congenital diaphragmatic hernia (CDH). METHODS: This retrospective study included 46 cases of CDH which underwent a total of 69 fetal MRI scans (65 in-vivo and four postmortem) at the Medical University of Vienna during the period 1 January 2002 to 1 January 2017. Scans were performed between 16 and 38 gestational weeks using steady-state free precession, T2-weighted and T1-weighted sequences. MRI data were retrieved from the hospital database and manual segmentation of the diaphragm was performed with the open-source software, ITK-SNAP. The resulting 3D models of the fetal diaphragm and its defect(s) were validated by postmortem MRI segmentation and/or comparison of 3D model-based classification of the defect with a reference classification based on autopsy and/or surgery reports. Surface areas of the intact diaphragm and of the defect were measured and used to calculate defect-diaphragmatic ratios (DDR). The need for prosthetic patch repair and, in cases with repeated in-vivo fetal MRI scans, diaphragm growth dynamics, were analyzed based on DDR. RESULTS: Fetal MRI-based manual segmentation of the diaphragm in CDH was feasible for all 65 (100%) of the in-vivo fetal MRI scans. Based on the 3D diaphragmatic models, one bilateral and 45 unilateral defects (n = 47) were further classified as posterolateral (23/47, 48.9%), lateral (7/47, 14.9%) or hemidiaphragmatic (17/47, 36.2%) defects, and none (0%) was classified as anterolateral. This classification of defect location was correct in all 37 (100%) of the cases in which this information could be verified. Nineteen cases had a follow-up fetal MRI scan; in five (26.3%) of these, the initial CDH classification was altered by the results of the second scan. Thirty-three fetuses underwent postnatal diaphragmatic surgical repair; 20 fetuses (all of those with DDR ≥ 54 and 88% of those with DDR > 30) received a diaphragmatic patch, while the other 13 underwent primary surgical repair. Individual DDRs at initial and at follow-up in-vivo fetal MRI correlated significantly (P < 0.001). CONCLUSIONS: MRI-based 3D reconstruction of the fetal diaphragm in CDH has been validated to visualize, locate, classify and quantify the defect. Planning of postnatal surgery may be optimized by MRI-based prediction of the necessity for patch placement and the ability to personalize patch design based on 3D-printable templates. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Hernias Diafragmáticas Congénitas/diagnóstico por imagen , Imagenología Tridimensional , Imagen por Resonancia Magnética , Diagnóstico Prenatal , Femenino , Hernias Diafragmáticas Congénitas/cirugía , Humanos , Valor Predictivo de las Pruebas , Embarazo , Estudios Retrospectivos
16.
Bone ; 123: 76-85, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30898694

RESUMEN

The osteocyte lacunar-canalicular network (LCN) penetrates bone and houses the osteocytes and their processes. Despite its rather low volume fraction, the LCN represents an outstanding large surface that is possibly used by the osteocytes to interact with the surrounding mineralized bone matrix thereby contributing to mineral homeostasis. The aim of this study was to quantitatively describe such contributions by spatially correlating the local density of the LCN with the mineral content at the same location in micrometer-sized volume elements in human osteons. For this purpose, 65 osteons from the femur midshaft from healthy adults (n = 4) and children (n = 2) were structurally characterized with two different techniques. The 3D structure of the LCN in the osteons was imaged with confocal laser scanning microscopy after staining the bone samples with rhodamine. Subsequent image analysis provided the canalicular length density, i.e. the total length of the canaliculi per unit volume (µm/µm3). Quantitative information on the mineral content (wt%Ca) from the identical regions was obtained using quantitative backscattered electron imaging. As the LCN-porosity lowers the mineral content, a negative correlation between Ca content and network density was expected. Calculations predict a reduction of around -0.97 fmol Ca per µm of network. However, the experiment revealed for 62 out of 65 osteons a positive correlation resulting in an average additional Ca loading of +1.15 fmol per µm of canalicular network, i.e. an accumulation of mineral has occurred at dense network regions. We hypothesize that this accumulation happens in the close vicinity of canaliculi forming mineral reservoirs that can be utilized by osteocytes. Significant differences found between individuals indicate that the extent of mineral loading of the reservoir zone reflects an important parameter for mineral homeostasis.


Asunto(s)
Matriz Ósea/metabolismo , Osteón/metabolismo , Preescolar , Femenino , Humanos , Microscopía Confocal , Persona de Mediana Edad , Osteocitos/metabolismo
17.
AJNR Am J Neuroradiol ; 40(3): 576-581, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30792247

RESUMEN

BACKGROUND AND PURPOSE: In subjects with agenesis of the corpus callosum, a variety of structural brain alterations is already present during prenatal life. Quantification of these alterations in fetuses with associated brain or body malformations (corpus callosum agenesis and other related anomalies) and so-called isolated cases may help to optimize the challenging prognostic prenatal assessment of fetuses with corpus callosum agenesis. This fetal MR imaging study aimed to identify differences in the size of the prenatal hippocampus between subjects with isolated corpus callosum agenesis, corpus callosum agenesis and other related anomalies, and healthy controls. MATERIALS AND METHODS: Eighty-five in utero fetal brain MR imaging scans, (20-35 gestational weeks) were postprocessed using a high-resolution algorithm. On the basis of multiplanar T2-TSE sequences, 3D isovoxel datasets were generated, and both hippocampi and the intracranial volume were segmented. RESULTS: Hippocampal volumes increased linearly with gestational weeks in all 3 groups. One-way ANOVA demonstrated differences in hippocampal volumes between control and pathologic groups (isolated corpus callosum agenesis: left, P = .02; right, P = .04; corpus callosum agenesis and other related anomalies: P < .001). Differences among the pathologic groups were also present for both sides. Intracranial volume and right and left hippocampal volume ratios were different between corpus callosum agenesis cases and controls (P < .001). When we corrected for intracranial volume, no differences were found between corpus callosum agenesis and other associated anomalies and isolated corpus callosum agenesis (left, P = .77; right, P = .84). Hippocampal size differences were more pronounced at a later gestational age. CONCLUSIONS: Callosal agenesis apparently interferes with the normal process of hippocampal formation and growth, resulting in underdevelopment, which could account for certain learning and memory deficits in individuals with agenesis of the corpus callosum in later life.


Asunto(s)
Agenesia del Cuerpo Calloso/diagnóstico por imagen , Feto/diagnóstico por imagen , Hipocampo/diagnóstico por imagen , Agenesia del Cuerpo Calloso/patología , Cuerpo Calloso/diagnóstico por imagen , Cuerpo Calloso/embriología , Cuerpo Calloso/patología , Femenino , Feto/patología , Hipocampo/embriología , Hipocampo/patología , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Neuroimagen , Embarazo
18.
Orthopade ; 48(1): 105-116, 2019 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-30259059

RESUMEN

Platelet-rich plasma (PRP) and growth factors have been increasing in popularity for the orthopedic treatment of degenerative and traumatic diseases. The treatment concept is based on the substitution of growth-inducing substances in tissues with low or absent regeneration capacity (cartilage, tendons) as well as for the induction or further acceleration of growth and regeneration (bone, muscle). This review article provides an overview on the clinical feasibility of usage and a summary of the current study situation.


Asunto(s)
Sistema Musculoesquelético , Plasma Rico en Plaquetas , Cartílago , Péptidos y Proteínas de Señalización Intercelular , Tendones
19.
Eur J Radiol ; 108: 189-193, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30396654

RESUMEN

OBJECTIVE: Recently, a potentially useful diagnostic approach based on MR diffusion-tensor-imaging (DTI) was reported for the estimation of putative functional placenta tissue (PFPT), thus providing direct information about placental function. Yet, the relation between reduced PFPT and the phenomenon of brain-sparing remains unclear. This study aimed to investigate the relation between brain-sparing and reduced PFPT volume, as found in fetuses with intrauterine growth restriction (IUGR). METHODS: A total of 40 consecutive patients with a US-based diagnosis of placental IUGR were examined using fetal MRI. A control group of 78 patients who received fetal MRI, due to non-placental pathologies, was established. A somatic energy index was calculated as IE=1-(Vbrain/Vpfpt) from brain and PFPT volumes measured with DTI in both groups. IE, Vpfpt, and Vbrain were analyzed with respect to the gestational week. RESULTS: Vbrain corrected for gestational weeks was no different between both groups, while Vpfpt was significantly reduced in IUGR patients. IE was significantly different between both groups and indicated a higher Vbrain at a comparable Vpfpt. CONCLUSIONS: Fetuses with IUGR show preserved energetic resources necessary for brain growth. Because IE drops in IUGR more rapidly as pregnancy progresses, depending on Vpfpt, IE could prove useful for estimating fetal well-being.


Asunto(s)
Encéfalo/embriología , Encéfalo/patología , Retardo del Crecimiento Fetal/patología , Imagen por Resonancia Magnética/métodos , Placenta/diagnóstico por imagen , Placenta/patología , Adulto , Femenino , Edad Gestacional , Humanos , Tamaño de los Órganos , Embarazo , Diagnóstico Prenatal/métodos , Adulto Joven
20.
Sci Rep ; 8(1): 8802, 2018 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-29892047

RESUMEN

The early and accurate diagnosis of periprosthetic joint infection (PJI) can be challenging. Fibrinogen plays an important role in mediating inflammation of bacterial infections and therefore could be a valuable biomarker for PJI. The purpose of this study was to investigate the sensitivity and specificity of serum levels of fibrinogen in detecting PJI, and to compare the results with the established PJI biomarkers C-reactive protein (CRP) and leukocyte count. Eighty-four patients (124 surgeries) were prospectively included. The preoperatively analyzed parameters were fibrinogen, CRP and leukocyte count. The sensitivity and specificity of the biomarkers were calculated and compared. Fibrinogen (p < 0.001), CRP (p < 0.001) and leukocyte count (p < 0.001) had a statistically significant correlation with the criteria defining the presence of PJI. For fibrinogen, the value of 519 mg/dl had a sensitivity of 0.90 and a specificity of 0.34. The CRP cut-off point of 11.00 mg/dl had a sensitivity of 0.90 and a specificity of 0.74. The leukocyte count of 5.68 G/l had a sensitivity of 0.90 and a specificity of 0.39. Our results indicated that fibrinogen is a significant biomarker for detecting a bacterial PJI. It has shown to be a cost-efficient diagnostic support with high sensitivity and specificity.


Asunto(s)
Biomarcadores/sangre , Pruebas Diagnósticas de Rutina/métodos , Fibrinógeno/análisis , Osteoartritis/diagnóstico , Osteoartritis/patología , Infecciones Relacionadas con Prótesis/diagnóstico , Infecciones Relacionadas con Prótesis/patología , Anciano , Anciano de 80 o más Años , Proteína C-Reactiva/análisis , Costos y Análisis de Costo , Pruebas Diagnósticas de Rutina/economía , Humanos , Recuento de Leucocitos , Persona de Mediana Edad , Estudios Prospectivos , Sensibilidad y Especificidad , Suero/química
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