Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.083
Filtrar
Más filtros

Intervalo de año de publicación
1.
Blood ; 137(19): 2681-2693, 2021 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-33529319

RESUMEN

Patients with isolated pulmonary embolism (PE) have a distinct clinical profile from those with deep vein thrombosis (DVT)-associated PE, with more pulmonary conditions and atherosclerosis. These findings suggest a distinct molecular pathophysiology and the potential involvement of alternative pathways in isolated PE. To test this hypothesis, data from 532 individuals from the Genotyping and Molecular Phenotyping of Venous ThromboEmbolism Project, a multicenter prospective cohort study with extensive biobanking, were analyzed. Targeted, high-throughput proteomics, machine learning, and bioinformatic methods were applied to contrast the acute-phase plasma proteomes of isolated PE patients (n = 96) against those of patients with DVT-associated PE (n = 276) or isolated DVT (n = 160). This resulted in the identification of shared molecular processes between PE phenotypes, as well as an isolated PE-specific protein signature. Shared processes included upregulation of inflammation, response to oxidative stress, and the loss of pulmonary surfactant. The isolated PE-specific signature consisted of 5 proteins: interferon-γ, glial cell line-derived neurotrophic growth factor, polypeptide N-acetylgalactosaminyltransferase 3, peptidyl arginine deiminase type-2, and interleukin-15 receptor subunit α. These proteins were orthogonally validated using cis protein quantitative trait loci. External replication in an independent population-based cohort (n = 5778) further validated the proteomic results and showed that they were prognostic for incident primary isolated PE in individuals without history of VTE (median time to event: 2.9 years; interquartile range: 1.6-4.2 years), supporting their possible involvement in the early pathogenesis. This study has identified molecular overlaps and differences between VTE phenotypes. In particular, the results implicate noncanonical pathways more commonly associated with respiratory and atherosclerotic disease in the acute pathophysiology of isolated PE.


Asunto(s)
Proteoma , Embolia Pulmonar/metabolismo , Transcriptoma , Proteínas de Fase Aguda/biosíntesis , Adulto , Anciano , Aterosclerosis/complicaciones , Comorbilidad , Conjuntos de Datos como Asunto , Femenino , Estudios de Seguimiento , Regulación de la Expresión Génica , Factor Neurotrófico Derivado de la Línea Celular Glial/biosíntesis , Factor Neurotrófico Derivado de la Línea Celular Glial/genética , Humanos , Interferón gamma/biosíntesis , Interferón gamma/genética , Subunidad alfa del Receptor de Interleucina-15/biosíntesis , Subunidad alfa del Receptor de Interleucina-15/genética , Aprendizaje Automático , Masculino , Persona de Mediana Edad , N-Acetilgalactosaminiltransferasas/biosíntesis , N-Acetilgalactosaminiltransferasas/genética , Estrés Oxidativo , Estudios Prospectivos , Mapas de Interacción de Proteínas , Arginina Deiminasa Proteína-Tipo 2/biosíntesis , Arginina Deiminasa Proteína-Tipo 2/genética , Embolia Pulmonar/genética , Embolia Pulmonar/fisiopatología , Surfactantes Pulmonares , Sitios de Carácter Cuantitativo , Tromboembolia Venosa/metabolismo , Polipéptido N-Acetilgalactosaminiltransferasa
2.
Langenbecks Arch Surg ; 408(1): 8, 2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36602631

RESUMEN

PURPOSE: Autosomal dominant polycystic kidney disease (ADPKD) is a common hereditary disorder and accounts for 5-10% of all cases of kidney failure. 50% of ADPKD patients reach kidney failure by the age of 58 years requiring dialysis or transplantation. Nephrectomy is performed in up to 20% of patients due to compressive symptoms, renal-related complications or in preparation for kidney transplantation. However, due to the large kidney size in ADPKD, nephrectomy can come with a considerable burden. Here we evaluate our institution's experience of laparoscopic nephrectomy (LN) as an alternative to open nephrectomy (ON) for ADPKD patients. MATERIALS AND METHODS: We report the results of the first 12 consecutive LN for ADPKD from August 2020 to August 2021 in our institution. These results were compared with the 12 most recent performed ON for ADPKD at the same institution (09/2017 to 07/2020). Intra- and postoperative parameters were collected and analyzed. Health related quality of life (HRQoL) was assessed using the SF36 questionnaire. RESULTS: Age, sex, and median preoperative kidney volumes were not significantly different between the two analyzed groups. Intraoperative estimated blood loss was significantly less in the laparoscopic group (33 ml (0-200 ml)) in comparison to the open group (186 ml (0-800 ml)) and postoperative need for blood transfusion was significantly reduced in the laparoscopic group (p = 0.0462). Operative time was significantly longer if LN was performed (158 min (85-227 min)) compared to the open procedure (107 min (56-174 min)) (p = 0.0079). In both groups one postoperative complication Clavien Dindo ≥ 3 occurred with the need of revision surgery. SF36 HRQol questionnaire revealed excellent postoperative quality of life after LN. CONCLUSION: LN in ADPKD patients is a safe and effective operative procedure independent of kidney size with excellent postoperative outcomes and benefits of minimally invasive surgery. Compared with the open procedure patients profit from significantly less need for transfusion with comparable postoperative complication rates. However significant longer operation times need to be taken in account.


Asunto(s)
Laparoscopía , Riñón Poliquístico Autosómico Dominante , Insuficiencia Renal , Humanos , Persona de Mediana Edad , Riñón Poliquístico Autosómico Dominante/cirugía , Calidad de Vida , Estudios Retrospectivos , Nefrectomía/métodos , Laparoscopía/métodos , Complicaciones Posoperatorias/etiología , Insuficiencia Renal/complicaciones , Insuficiencia Renal/cirugía , Pérdida de Sangre Quirúrgica , Riñón
3.
Eur Heart J ; 43(36): 3387-3398, 2022 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-35484821

RESUMEN

AIMS: To systematically assess late outcomes of acute pulmonary embolism (PE) and to investigate the clinical implications of post-PE impairment (PPEI) fulfilling prospectively defined criteria. METHODS AND RESULTS: A prospective multicentre observational cohort study was conducted in 17 large-volume centres across Germany. Adult consecutive patients with confirmed acute symptomatic PE were followed with a standardized assessment plan and pre-defined visits at 3, 12, and 24 months. The co-primary outcomes were (i) diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH), and (ii) PPEI, a combination of persistent or worsening clinical, functional, biochemical, and imaging parameters during follow-up. A total of 1017 patients (45% women, median age 64 years) were included in the primary analysis. They were followed for a median duration of 732 days after PE diagnosis. The CTEPH was diagnosed in 16 (1.6%) patients, after a median of 129 days; the estimated 2-year cumulative incidence was 2.3% (1.2-4.4%). Overall, 880 patients were evaluable for PPEI; the 2-year cumulative incidence was 16.0% (95% confidence interval 12.8-20.8%). The PPEI helped to identify 15 of the 16 patients diagnosed with CTEPH during follow-up (hazard ratio for CTEPH vs. no CTEPH 393; 95% confidence interval 73-2119). Patients with PPEI had a higher risk of re-hospitalization and death as well as worse quality of life compared with those without PPEI. CONCLUSION: In this prospective study, the cumulative 2-year incidence of CTEPH was 2.3%, but PPEI diagnosed by standardized criteria was frequent. Our findings support systematic follow-up of patients after acute PE and may help to optimize guideline recommendations and algorithms for post-PE care.


Asunto(s)
Hipertensión Pulmonar , Embolia Pulmonar , Enfermedad Aguda , Adulto , Enfermedad Crónica , Femenino , Humanos , Hipertensión Pulmonar/complicaciones , Hipertensión Pulmonar/epidemiología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Embolia Pulmonar/complicaciones , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/epidemiología , Calidad de Vida , Factores de Riesgo
4.
Pneumologie ; 2023 Oct 13.
Artículo en Alemán | MEDLINE | ID: mdl-37832578

RESUMEN

The guideline update outlines the advantages as well as the limitations of NIV in the treatment of acute respiratory failure in daily clinical practice and in different indications.Non-invasive ventilation (NIV) has a high value in therapy of hypercapnic acute respiratory failure, as it significantly reduces the length of ICU stay and hospitalization as well as mortality.Patients with cardiopulmonary edema and acute respiratory failure should be treated with continuous positive airway pressure (CPAP) and oxygen in addition to necessary cardiological interventions. This should be done already prehospital and in the emergency department.In case of other forms of acute hypoxaemic respiratory failure with only mild or moderately disturbed gas exchange (PaO2/FiO2 > 150 mmHg) there is no significant advantage or disadvantage compared to high flow nasal oxygen (HFNO). In severe forms of ARDS NIV is associated with high rates of treatment failure and mortality, especially in cases with NIV-failure and delayed intubation.NIV should be used for preoxygenation before intubation. In patients at risk, NIV is recommended to reduce extubation failure. In the weaning process from invasive ventilation NIV essentially reduces the risk of reintubation in hypercapnic patients. NIV is regarded useful within palliative care for reduction of dyspnea and improving quality of life, but here in concurrence to HFNO, which is regarded as more comfortable. Meanwhile NIV is also recommended in prehospital setting, especially in hypercapnic respiratory failure and pulmonary edema.With appropriate monitoring in an intensive care unit NIV can also be successfully applied in pediatric patients with acute respiratory insufficiency.

5.
Prog Urol ; 32(5): 388-399, 2022 Apr.
Artículo en Francés | MEDLINE | ID: mdl-35125316

RESUMEN

INTRODUCTION: Inflammatory and sensory chronic bladder diseases have a significant impact on quality of life. These pathologies share alteration of the layer between urine and urothelium, making the use of topical agents appropriate. OBJECTIVES: Review the efficacy and tolerance of intravesical treatments for these pathologies. Give practical guidelines for the use of agents currently available in France. METHOD: A narrative review was performed in March 2021 using PubMed/MEDLINE, Google Scholar and the international guidelines. Pharmaceutical companies and pharmacies were interviewed. RESULTS: Although numerous molecules were tested over the last 5 decades, only dimethylsulfoxyde and glycosaminoglycans are available in France today. Results are promising: response rates are up to 95% and 84% respectively in bladder pain syndrome. In urinary tract infections, glycosaminoglycans could decrease annual number of cystitis by 2.56 (95% confidence interval (CI) -3.86, -1.26; P<0.001) and increase the time to first cystitis recurrence by 130 days (95% CI: 5.84 - 254.26; P=0.04). In radiation cystitis, results could be comparable to hyperbaric oxygen regarding pain and frequency of voiding (-1.31±1.3 visual analogic scale et -1.5±1.4 voiding per day, respectively, at 12 months, P<0.01). However, literature has a low level of evidence. CONCLUSION: Chronic bladder diseases have limited treatment options. Intravesical agents are a good alternative, although their cost is significant and their outcome uncertain.


Asunto(s)
Cistitis Intersticial , Cistitis , Administración Intravesical , Enfermedad Crónica , Cistitis/tratamiento farmacológico , Cistitis Intersticial/tratamiento farmacológico , Femenino , Glicosaminoglicanos/uso terapéutico , Humanos , Masculino , Calidad de Vida
6.
Prog Urol ; 32(4): 247-257, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34920924

RESUMEN

OBJECTIVE: To determine the usefulness of mid-urethral slings (MUS) in the surgical management of women presenting with urinary stress incontinence (USI) METHOD: A consensus committee of multidisciplinary experts (CUROPF) was convened and focused on PICO questions concerning the efficacy and safety of MUS surgery compared to other procedures and concerning which approach (retropubic (RP) vs transobturator (TO)) should be proposed as a first-line MUS surgery for specific subpopulations (obese; intrinsic sphincteric deficiency (ISD); elderly) RESULTS: As compared to other procedures (urethral bulking agents, traditional slings and open colposuspension), the MUS procedure should be proposed as the first-line surgical therapy (strong agreement). MUS surgery can be associated with complications and proper pre-operative informed consent is mandatory (strong agreement). Mini-slings (SIS/SIMS) should only be proposed in clinical trials (strong agreement). Both RP and TO approaches may be proposed for the insertion of MUS (strong agreement). However, if the woman is willing to accept a moderate increase in per-operative risk, the RP approach should be preferred (strong agreement) since it is associated with higher very long-term cure rates and as it is possible to completely remove the sling surgically if a severe complication occurs. The RP approach should be used for the insertion of MUS in a woman presenting with ISD (strong agreement). Either the RP or TO approach should be used for the insertion of MUS in an obese woman presenting with USI (strong agreement). In very obese women (BMI ≥35-40kg/m2), weight loss should be preferred prior to MUS surgery and bariatric surgery should be discussed (strong agreement) CONCLUSION: The current Opinion provides an appropriate strategy for both the selection of patients and the best therapeutic approach in women presenting with USI.


Asunto(s)
Cabestrillo Suburetral , Enfermedades Uretrales , Incontinencia Urinaria de Esfuerzo , Anciano , Femenino , Humanos , Masculino , Cabestrillo Suburetral/efectos adversos , Resultado del Tratamiento , Uretra , Enfermedades Uretrales/complicaciones , Incontinencia Urinaria de Esfuerzo/etiología , Incontinencia Urinaria de Esfuerzo/cirugía , Procedimientos Quirúrgicos Urológicos/métodos
7.
Mol Biol Rep ; 48(4): 3799-3812, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33761086

RESUMEN

Since the discovery of dental pulp stem cells, a lot of teams have expressed an interest in dental pulp regeneration. Many approaches, experimental models and biological explorations have been developed, each including the use of stem cells and scaffolds with the final goal being clinical application in humans. In this review, the authors' objective was to compare the experimental models and strategies used for the development of biomaterials for tissue engineering of dental pulp with stem cells. Electronic queries were conducted on PubMed using the following terms: pulp regeneration, scaffold, stem cells, tissue engineering and biomaterial. The extracted data included the following information: the strategy envisaged, the type of stem cells, the experimental models, the exploration or analysis methods, the cytotoxicity or viability or proliferation cellular tests, the tests of scaffold antibacterial properties and take into account the vascularization of the regenerated dental pulp. From the 71 selected articles, 59% focused on the "cell-transplantation" strategy, 82% used in vitro experimentation, 58% in vivo animal models and only one described an in vivo in situ human clinical study. 87% used dental pulp stem cells. A majority of the studies reported histology (75%) and immunohistochemistry explorations (66%). 73% mentioned the use of cytotoxicity, proliferation or viability tests. 48% took vascularization into account but only 6% studied the antibacterial properties of the scaffolds. This article gives an overview of the methods used to regenerate dental pulp from stem cells and should help researchers create the best development strategies for research in this field.


Asunto(s)
Implantación Dental/métodos , Pulpa Dental/fisiología , Regeneración , Trasplante de Células Madre/métodos , Ingeniería de Tejidos/métodos , Animales , Implantación Dental/efectos adversos , Pulpa Dental/irrigación sanguínea , Pulpa Dental/citología , Humanos , Neovascularización Fisiológica , Trasplante de Células Madre/efectos adversos
8.
Avian Pathol ; 50(6): 500-506, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34463594

RESUMEN

Optimal intestinal health is a prerequisite for sustainable poultry production. Intestinal health can be evaluated by scoring macroscopic intestinal abnormalities and by histological measurements. The aim of this study was to evaluate correlations between macroscopic gut appearance scoring (GAS), coccidiosis lesion scoring, histological measurements and performance parameters in broilers under field conditions. Therefore, a cross-sectional study was performed on 50 broiler farms where birds were sampled at 28 days of age. The GAS was determined by scoring the absence or presence of 10 macroscopically visible parameters of the gastrointestinal tract, yielding a GAS between 0 and 10, with 0 meaning no gut abnormalities. On individual bird level, when birds had a GAS score of 6 or higher, significantly shorter villi were found in the duodenum. Also, CD3+ T-lymphocyte area percentage in the duodenal mucosa was significantly negatively correlated to villus length. On farm level, the average feed conversion ratio (FCR) was 1.59 ± 0.04 [1.52-1.73]. However, no correlations were found between the GAS at the age of 28 days and the prevalence of coccidiosis, nor did coccidiosis lesion scoring correlate with the FCR. Also, a higher GAS could not be associated with a higher FCR. In conclusion, on all farms a certain degree of macroscopic visible gut and coccidiosis lesions were present in birds of 28 days of age, while this did not correlate with the FCR. This suggests that broilers are able to cope with a certain level of gut damage before it influences the overall performance.


Asunto(s)
Pollos , Animales , Estudios Transversales
9.
Pneumologie ; 75(2): 122-137, 2021 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-33578434

RESUMEN

Pulmonary hypertension (PH) can be diagnosed in the context of connective tissue diseases (CTD) as well as in elderly patients with multiple comorbidities. A correct clinical differential diagnosis and classification is essential before adequate therapeutic decisions can be made. Differential diagnosis of PH in CTD comprises associated pulmonary arterial hypertension (APAH), group 2 or 3 PH (PH arising from left heart or chronic lung disease), chronic thromboembolic PH (PH) and group 5 (e. g. in the context of terminal renal insufficiency). This is also true of elderly patients in whom the decision has to be made if the increasing number of coincident diseases lead to PH or have to be interpreted as comorbidities. In this manuscript, the differential diagnosis of PH is elucidated, focusing on CTD, in the context of left heart disease and chronic lung disease. Furthermore, criteria are presented facilitating an objective approach in this context.


Asunto(s)
Diagnóstico Diferencial , Cardiopatías , Hipertensión Pulmonar , Enfermedades Pulmonares/diagnóstico , Enfermedades del Tejido Conjuntivo/complicaciones , Enfermedades del Tejido Conjuntivo/diagnóstico , Cardiopatías/diagnóstico , Humanos , Hipertensión Pulmonar/diagnóstico
10.
Prog Urol ; 31(17): 1141-1166, 2021 Dec.
Artículo en Francés | MEDLINE | ID: mdl-34794867

RESUMEN

INTRODUCTION: Placement of a mid-urethral sling is the gold standard in the surgical management of stress urinary incontinence in women in France. The cure rate of this material is no longer to be demonstrated, but the per- and post-operative complications are currently the subject of a growing controversy not only in Europe but also across the Channel and across the Atlantic, having led to the modification of operative indications. In France, recommendations are also evolving with a stricter framework for indications for surgery by multidisciplinary consultation meeting and an obligation for postoperative follow-up in the short and long term. OBJECTIVES: In this context, CUROPF realized a review of the literature bringing together the available scientific evidence concerning the occurrence of per- and post-operative complications relating to the installation of mid urethral sling. The bibliographic search was carried out using the Medline database and 123 articles were selected. RESULTS: Analysis of the data highlights various complications, depending on the implanted material, the patient and the indication for surgery. The retro-pubic mid urethral sling provides more bladder erosion during surgery (up to 14%), more suprapubic pain (up to 4%) and more acute urinary retention (up to 19,7%) and postoperative dysuria (up to 26%). The trans obturator mid-urethral sling is responsible for more vaginal erosion during the operation (up to 10,9%), more lower limb pain of neurological origin (up to 26,7%). The risk of developing over active bladder is similar in both procedures (up to 33%). But these risks of complications must be balanced by the strong impact of urinary incontinence surgery on the overall quality of life of these women. CONCLUSION: Thus, surgical failure and long term complications exist but should not limit the surgical management of stress urinary incontinence with mid urethral tape. Women should be treated with individualized decision-making process and long-term follow -up is necessary.


Asunto(s)
Cabestrillo Suburetral , Incontinencia Urinaria de Esfuerzo , Urología , Femenino , Humanos , Calidad de Vida , Cabestrillo Suburetral/efectos adversos , Resultado del Tratamiento , Incontinencia Urinaria de Esfuerzo/cirugía , Procedimientos Quirúrgicos Urológicos/efectos adversos
11.
Opt Lett ; 45(9): 2494-2497, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32356799

RESUMEN

We demonstrate terahertz (THz) generation using the tilted pulse front method in lithium niobate, driven at an unprecedented high average power of more than 100 W and at a 13.3 MHz repetition rate, provided by a compact amplifier-free mode-locked thin-disk oscillator. The conversion efficiency was optimized with respect to the pump spot size and pump pulse duration, enabling us to generate a maximum THz average power of 66 mW, which is, to the best of our knowledge, the highest reported to date from a laser-driven, few-cycle THz source. Furthermore, we identify beam walk-off as the main obstacle that currently limits the conversion efficiency in this excitation regime (with moderate pulse energies and small spot sizes). Further upscaling to the watt level and beyond is within reach, paving the way for linear and nonlinear high average power THz spectroscopy experiments with an exceptional signal-to-noise ratio at megahertz repetition rates.

12.
World J Surg ; 44(5): 1681, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32052103

RESUMEN

This article contains parts of the doctoral thesis of F. Meyer.

13.
World J Surg ; 44(2): 594-603, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31605171

RESUMEN

BACKGROUND: In contrast to exocrine pancreatic carcinomas, prognosis and treatment of pancreatic neuroendocrine neoplasms (PNEN) are significantly different. The variable growth pattern and associated clinical situation of functioning and non-functioning PNEN demand an individualized surgical approach. However, due to the scarce evidence associated with the rare disease, guidelines lack detailed recommendations for indication and for the required extent of surgical resection. METHODS: In a retrospective single-center study from 1990 to 2018, 239 patients with PNEN were identified. Clinical data were collected in the MaDoc database of the University Medical Center Mainz. A total of 155 non-functional PNEN were selected for further analysis. RESULTS: According to the classification of NET by the WHO in 2017, 28.8% (n = 40) of the tumors were G1, 61.9% (n = 86) G2, and 9.4% (n = 13) G3. In 73 patients, hepatic metastases were present. Sixty patients had lymph node metastasis. An R0 resection was achieved in 98 cases, an R1 situation in 10 cases. Five times, a tumor debulking was carried out (R2) and 5 times the operation was aborted without any resection because of the advanced tumor stage. A relapse occurred in 29 patients. Different prognostic factors (grade, tumor size, age) were analyzed. Grade-dependent 10-year overall survival rates were 79.5% (grade 1) and 60.1% (grade 2), respectively. The survival rate of grade 3 patients was limited to 66.7% after 13 months. CONCLUSION: In our study, patients with non-functioning PNEN had a longer overall survival after successful R0 resection. The risk analysis confirmed a Ki-67 cutoff value of 5%, which divided a high- and low-risk group. Patients with a PNEC G3 (Ki-67 index > 50%) had a very poor prognosis.


Asunto(s)
Tumores Neuroendocrinos/mortalidad , Neoplasias Pancreáticas/mortalidad , Adulto , Anciano , Femenino , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Tumores Neuroendocrinos/patología , Tumores Neuroendocrinos/cirugía , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Pronóstico , Estudios Retrospectivos , Riesgo
14.
Pneumologie ; 74(12): 847-863, 2020 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-32663892

RESUMEN

At the 6th World Symposium on Pulmonary Hypertension (WSPH), which took place from February 27 until March 1, 2018 in Nice, scientific progress over the past 5 years in the field of pulmonary hypertension (PH) was presented by 13 working groups. The results of the discussion were published as proceedings towards the end of 2018. One of the major changes suggested by the WSPH was the lowering of the diagnostic threshold for PH from ≥ 25 to > 20 mmHg mean pulmonary arterial pressure, measured by right heart catheterization at rest. In addition, the pulmonary vascular resistance was introduced into the definition of PH, which underlines the importance of cardiac output determination at the diagnostic right heart catheterization.In this article, we discuss the rationale and possible consequences of a changed PH definition in the context of the current literature. Further, we provide a current overview on non-invasive and invasive methods for diagnosis, differential diagnosis, and prognosis of PH, including exercise tests.


Asunto(s)
Hipertensión Pulmonar/diagnóstico , Hipertensión Pulmonar/terapia , Guías de Práctica Clínica como Asunto/normas , Cateterismo Cardíaco , Humanos
15.
Opt Express ; 27(21): 30340-30349, 2019 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-31684282

RESUMEN

We demonstrate a high repetition-rate, single-cycle THz source with a maximum average power of 1.35 mW, operating at a center frequency of 2 THz. This result was obtained by optical rectification (OR) in GaP using an amplifier-free, nonlinearly compressed modelocked thin-disk oscillator based on Yb:YAG, delivering 8.4 µJ pulses with 88 fs duration at a repetition rate of 13.4 MHz, resulting in driving pulses for OR with 112 W average power and 80 MW peak power. To the best of our knowledge, our result represents the highest average power so far achieved with OR in GaP. The demonstrated performance is very attractive for improving current linear THz time-domain spectroscopy experiments, which are currently restricted by low signal-to-noise ratio and long measurement times.

16.
Nanotechnology ; 30(37): 374002, 2019 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-31195384

RESUMEN

Owing to the great potential of iron oxide nanoparticles (NPs) for nanomedicine, large efforts have been made to better control their magnetic properties, especially their magnetic anisotropy to provide NPs able to combine imaging by MRI and therapy by magnetic hyperthermia. In that context, the design of anisotropic NPs appears as a very promising and efficient strategy. Furthermore, their bioactive coating also remains a challenge as it should provide colloidal stability, biocompatibility, furtivity along with good water diffusion for MRI. By taking advantage of our controlled synthesis method of iron oxide NPs with different shapes (cubic, spherical, octopod and nanoplate), we demonstrate here that the dendron coating, shown previously to be very suitable for 10 nm sized iron oxide, also provided very good colloidal, MRI and antifouling properties to the anisotropic shaped NPs. These antifouling properties, demonstrated through several experiments and characterizations, are very promising to achieve specific targeting of disease tissues without affecting healthy organs. On the other hand, the magnetic hyperthermia properties were shown to depend on the saturation magnetization and the ability of NPs to self-align, confirming the need of a balance between crystalline and dipolar magnetic anisotropies.

17.
Phys Chem Chem Phys ; 21(24): 13207-13214, 2019 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-31179459

RESUMEN

The local valence orbital structure of solid glycine, diglycine, and triglycine is studied using soft X-ray emission spectroscopy (XES), resonant inelastic soft X-ray scattering (RIXS) maps, and spectra calculations based on density-functional theory. Using a building block approach, the contributions of the different functional groups of the peptides are separated. Cuts through the RIXS maps furthermore allow monitoring selective excitations of the amino and peptide functional units, leading to a modification of the currently established assignment of spectral contributions. The results thus paint a new-and-improved picture of the peptide bond, enhance the understanding of larger molecules with peptide bonds, and simplify the investigation of such molecules in aqueous environment.


Asunto(s)
Modelos Químicos , Péptidos/química , Dispersión Dinámica de Luz , Electrones , Glicina/química , Glicilglicina/química , Oligopéptidos/química , Teoría Cuántica , Agua/química , Difracción de Rayos X
18.
Nano Lett ; 18(9): 5673-5680, 2018 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-30134098

RESUMEN

Difficulties in obtaining high-performance p-type transistors and gate insulator charge-trapping effects present two major challenges for III-V complementary metal-oxide semiconductor (CMOS) electronics. We report a p-GaAs nanowire metal-semiconductor field-effect transistor (MESFET) that eliminates the need for a gate insulator by exploiting the Schottky barrier at the metal-GaAs interface. Our device beats the best-performing p-GaSb nanowire metal-oxide-semiconductor field effect transistor (MOSFET), giving a typical subthreshold swing of 62 mV/dec, within 4% of the thermal limit, on-off ratio ∼105, on-resistance ∼700 kΩ, contact resistance ∼30 kΩ, peak transconductance 1.2 µS/µm, and high-fidelity ac operation at frequencies up to 10 kHz. The device consists of a GaAs nanowire with an undoped core and heavily Be-doped shell. We carefully etch back the nanowire at the gate locations to obtain Schottky-barrier insulated gates while leaving the doped shell intact at the contacts to obtain low contact resistance. Our device opens a path to all-GaAs nanowire MESFET complementary circuits with simplified fabrication and improved performance.

19.
HNO ; 67(3): 207-211, 2019 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-30377744

RESUMEN

BACKGROUND: Neck tumors are challenging regarding the diagnostic and therapeutic management particularly in cases of malignant growth near relevant vessels to achieve R0 resection status and the best prognosis. AIM: The aim of this case report on a patient with a rare malignant tumor of the glomus caroticum (paraganglioma) is to present the successful outcome of a demanding interdisciplinary surgical approach (otorhinolaryngology and vascular surgery). Surgical re-intervention was necessary due to malignant tumor growth (detected in the histopathological investigation of the first specimen) including vascular resection using a hybrid graft for vascular reconstruction of the internal carotid artery near the skull base. CASE REPORT: A 38-year-old male patient underwent magnetic resonance angiography and digital subtraction angiography to clarify the diagnosis of a tumor in the right neck. This was preoperatively embolized and subsequently resected including vascular reconstruction using a prosthetic interposition graft (7 cm; W.L. Gore, Putzbrunn, Germany) between the common and internal carotid arteries. HISTOLOGY: malignant paraganglioma 40 mm in diameter with haemangiosis et lymphangiosis carcinomatosa demonstrating lymph node metastasis and prompting re-operation (neck dissection levels II, III, IV, V). This was followed by a novel vascular reconstruction using a GORE® hybrid vascular graft prosthetic stent (W.L. Gore) as interposition graft because of the short extracranial stump of the distal internal carotid artery near the skull base and to limit clamping time. Early postoperative outcome revealed no complications and after 24 months there were no signs or symptoms of recurrent tumor growth. CONCLUSION: Extended resections, if necessary including vascular (arterial) segments, aim at achieving R0 classification as shown in this extremely rare and usually challenging malignant tumor. Hybrid vascular prostheses are suitable for time-saving vascular reconstruction (>50%) to provide sufficient blood supply.


Asunto(s)
Tumor del Cuerpo Carotídeo , Cuerpo Carotídeo , Paraganglioma , Adulto , Arteria Carótida Interna/cirugía , Tumor del Cuerpo Carotídeo/cirugía , Alemania , Humanos , Masculino , Paraganglioma/cirugía , Base del Cráneo
20.
Opt Lett ; 43(24): 5909-5912, 2018 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-30547967

RESUMEN

We demonstrate terahertz (THz) generation at megahertz repetition rate by optical rectification in GaP crystals, using excitation average power levels exceeding 100 W. The laser source is a state-of-the-art diode-pumped Yb:YAG SESAM-mode-locked thin-disk laser, capable of generating 580 fs pulses at an average power up to 120 W and a repetition rate of 13.4 MHz directly from a one-box oscillator, without the need for any extra amplification stages. In this first demonstration, we measure a maximum THz average power of 78 µW at a central frequency of 0.8 THz. Our results show that optical rectification of state-of-the-art high average power ultrafast sources in nonlinear crystals is within reach and paves the way toward high average power, ultrafast laser pumped THz sources.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA