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1.
Periodontol 2000 ; 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38778518

RESUMEN

Currently, autologous platelet concentrates (APCs) are frequently used for soft- and hard-tissue regeneration, not only within the oral cavity, but also extra-orally including chronic wounds, burns, joints, dermatological conditions, among others. The benefits of APCs are largely influenced by the treatment strategy but also their preparation. This paper therefore discusses in detail: the physical properties of blood cells, the basic principles of blood centrifugation, the impact of the centrifugation protocol (rotations/revolutions per minute, g-force, variation between centrifuges), the importance of timing during the preparation of APCs, the impact of the inner surface of the blood tubes, the use/nonuse of anticoagulants within APC tubes, the impact of the patient's hematocrit, age, and gender, as well as the important requirements for an optimal centrifugation protocol. All these variables indeed have a significant impact on the clinical outcome of APCs.

2.
Exp Brain Res ; 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39034329

RESUMEN

Transspinal (or transcutaneous spinal cord) stimulation is a promising noninvasive method that may strengthen the intrinsic spinal neural connectivity in neurological disorders. In this study we assessed the effects of cervical transspinal stimulation on the amplitude of leg transspinal evoked potentials (TEPs), and the effects of lumbosacral transspinal stimulation on the amplitude of arm TEPs. Control TEPs were recorded following transspinal stimulation with one cathode electrode placed either on Cervical 3 (21.3 ± 1.7 mA) or Thoracic 10 (23.6 ± 16.5 mA) vertebrae levels. Associated anodes were placed bilaterally on clavicles or iliac crests. Cervical transspinal conditioning stimulation produced short latency inhibition of TEPs recorded from left soleus (ranging from - 6.11 to -3.87% of control TEP at C-T intervals of -50, -25, -20, -15, -10, 15 ms), right semitendinosus (ranging from - 11.1 to -4.55% of control TEP at C-T intervals of -20, -15, 15 ms), and right vastus lateralis (ranging from - 13.3 to -8.44% of control TEP at C-T intervals of -20 and - 15 ms) (p < 0.05). Lumbosacral transspinal conditioning stimulation produced no significant effects on arm TEPs. We conclude that in the resting state, cervical transspinal stimulation affects the net motor output of leg motoneurons under the experimental conditions used in this study. Further investigations are warranted to determine whether this protocol may reactivate local spinal circuitry after stroke or spinal cord injury and may have a significant effect in synchronization of upper and lower limb muscle synergies during rhythmic activities like locomotion or cycling.

3.
Exp Brain Res ; 242(6): 1267-1276, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38366214

RESUMEN

The soleus H-reflex modulation pattern was investigated during stepping following transspinal stimulation over the thoracolumbar region at 15, 30, and 50 Hz with 10 kHz carry-over frequency above and below the paresthesia threshold. The soleus H-reflex was elicited by posterior tibial nerve stimulation with a single 1 ms pulse at an intensity that the M-wave amplitudes ranged from 0 to 15% of the maximal M-wave evoked 80 ms after the test stimulus, and the soleus H-reflex was half the size of the maximal H-reflex evoked on the ascending portion of the recruitment curve. During treadmill walking, the soleus H-reflex was elicited every 2 or 3 steps, and stimuli were randomly dispersed across the step cycle which was divided in 16 equal bins. For each subject and condition, the soleus M-wave and H-reflex were normalized to the maximal M-wave. The soleus background electromyographic (EMG) activity was estimated as the linear envelope for 50 ms duration starting at 100 ms before posterior tibial nerve stimulation for each bin. The gain was determined as the slope of the relationship between the soleus H-reflex and the soleus background EMG activity. The soleus H-reflex phase-dependent amplitude modulation remained unaltered during transspinal stimulation, regardless frequency, or intensity. Similarly, the H-reflex slope and intercept remained the same for all transspinal stimulation conditions tested. Locomotor EMG activity was increased in knee extensor muscles during transspinal stimulation at 30 and 50 Hz throughout the step cycle while no effects were observed in flexor muscles. These findings suggest that transspinal stimulation above and below the paresthesia threshold at 15, 30, and 50 Hz does not block or impair spinal integration of proprioceptive inputs and increases activity of thigh muscles that affect both hip and knee joint movement. Transspinal stimulation may serve as a neurorecovery strategy to augment standing or walking ability in upper motoneuron lesions.


Asunto(s)
Electromiografía , Reflejo H , Músculo Esquelético , Caminata , Humanos , Reflejo H/fisiología , Caminata/fisiología , Masculino , Músculo Esquelético/fisiología , Adulto , Adulto Joven , Femenino , Estimulación Eléctrica/métodos , Nervio Tibial/fisiología , Médula Espinal/fisiología
4.
Thorac Cardiovasc Surg ; 71(3): 171-177, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-35644132

RESUMEN

BACKGROUND: Transmitral myectomy for symptomatic hypertrophic obstructive cardiomyopathy is possible with existence of substantial mitral valve disease. We present herein our experience of minimally invasive transmitral septal myectomy combined with mitral valve surgery through right anterior mini-thoracotomy in the past 4 years at our institution. METHODS: Between March 2017 and October 2020, 14 patients with hypertrophic obstructive cardiomyopathy and mitral valve disease required minimally invasive transmitral septal myectomy combined with mitral valve reconstruction or replacement at our institution. Mean age of patients was 54.2 ± 11.4 and 42.9% (n = 6) were female. Twelve patients (85.1%) were in New York Heart Association class III to IV and 6 patients (42.9%) presented with persistent atrial fibrillation. Clinical data were prospectively entered into our institutional database. RESULTS: Cardiopulmonary bypass time accounted for 140.2 ± 32.6 minutes and the myocardial ischemic time was 78.5 ± 12.4 minutes. Thirty-day mortality and overall mortality were zero. Peak ventricular outflow gradient decreased from 75.2 ± 12.7 to 9.4 ± 2.3 mm Hg (p < 0.0001). Simultaneously, mitral valve reconstruction and replacement were performed in 11 (78.6%) and 3 (21.4%) patients, respectively. No systolic anterior motion was seen in patients with mitral valve repair. No conversion to full sternotomy and/or rethoracotomy was noted. During a mean follow-up period of 24 ± 13 months, no patient required reoperation, no recurrence mitral regurgitation, and left ventricular outflow tract obstruction. CONCLUSION: Transmitral septal myectomy combined with mitral valve surgery through right anterior mini-thoracotomy can be performed safely with excellent surgical outcomes.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Cardiomiopatía Hipertrófica , Enfermedades de las Válvulas Cardíacas , Insuficiencia de la Válvula Mitral , Humanos , Femenino , Masculino , Válvula Mitral/cirugía , Resultado del Tratamiento , Insuficiencia de la Válvula Mitral/cirugía , Enfermedades de las Válvulas Cardíacas/complicaciones , Cardiomiopatía Hipertrófica/cirugía
5.
Eur Arch Otorhinolaryngol ; 280(11): 4885-4894, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37195345

RESUMEN

PURPOSE: To highlight the changes in the management of vestibular schwannoma (VS) since 2004 with a focus on small- to middle-size VS. METHODS: Retrospective analysis of the decisions made in skull base tumor board between 2004 and 2021. RESULTS: 1819 decisions were analyzed (average age 59.25, 54% females). Overall, 850 (47%) cases were allocated to a Wait and Scan (WS) approach, 416 (23%) received radiotherapy and 553 (30%) were treated surgically (MS). All stages considered WS increased from 39% before 2010 to 50% after 2010. Similarly, Stereotactic Radio Therapy (SRT) increased from 5 to 18%. MS decreased from 46 to 25%. It was more commonly proposed to younger patients and larger tumors, p < 0.001. For Koos stages 1, 2, and 3 there was a statistically significant increase in SRT, and a decrease in MS, p < 0.001. WS also increased for stages 1 and 2. However, such a trend was not observed for stage 3. MS remained the primary treatment modality for stage 4 tumors throughout the study period, p = 0.057. The significance of advanced age as a factor favoring SRT decreased over time. The opposite is true for serviceable hearing. There was also a decrease in the percentage of the justification "young age" in the MS category. CONCLUSION: The is a continuing trend towards non-surgical treatment. Small- to medium-sized VS witnessed an increase in both WS and SRT. There is only an increase in SRT for moderately large VS. Physicians are less and less considering young age as a factor favoring MS over SRT. There is a tendency towards favoring SRT when hearing is serviceable.


Asunto(s)
Neuroma Acústico , Femenino , Humanos , Persona de Mediana Edad , Masculino , Neuroma Acústico/cirugía , Neuroma Acústico/patología , Estudios Retrospectivos , Resultado del Tratamiento , Audición , Fraccionamiento de la Dosis de Radiación , Estudios de Seguimiento
6.
Sensors (Basel) ; 23(2)2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36679840

RESUMEN

The evolution towards next-generation Beyond 5G (B5G) networks will require not only innovation in transport technologies but also the adoption of smarter, more efficient operations of the use cases that are foreseen to be the high consumers of network resources in the next decades. Among different B5G use cases, the Digital Twin (DT) has been identified as a key high bandwidth-demanding use case. The creation and operation of a DT require the continuous collection of an enormous and widely distributed amount of sensor telemetry data which can overwhelm the transport layer. Therefore, the reduction in such transported telemetry data is an essential objective of smart use case operation. Moreover, deep telemetry data analysis, i.e., anomaly detection, can be executed in a hierarchical way to reduce the processing needed to perform such analysis in a centralized way. In this paper, we propose a smart management system consisting of a hierarchical architecture for telemetry sensor data analysis using deep autoencoders (AEs). The system contains AE-based methods for the adaptive compression of telemetry time series data using pools of AEs (called AAC), as well as for anomaly detection in single (called SS-AD) and multiple (called MS-AGD) sensor streams. Numerical results using experimental telemetry data show compression ratios of up to 64% with reconstruction errors of less than 1%, clearly improving upon the benchmark state-of-the-art methods. In addition, fast and accurate anomaly detection is demonstrated for both single and multiple-sensor scenarios. Finally, a great reduction in transport network capacity resources of 50% and more is obtained by smart use case operation for distributed DT scenarios.


Asunto(s)
Compresión de Datos , Aprendizaje Profundo , Benchmarking , Análisis de Datos , Fenómenos Físicos
7.
Cryobiology ; 106: 66-72, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35429488

RESUMEN

The aim of this study was to compare the effect of two permeant-cryoprotectants, dimethylacetamide (DMA) and N-methylacetamide (NMA) used at different concentrations (0%, 2%, 4%, 6%) on the quality and fertility of post-thaw rooster semen. Ejaculates were processed in 7 treatments: Lake pre-freezing+0.1 M trehalose (LPF-T) (control treatment), LPF-T+2% DMA, LPF-T+4% DMA, LPF-T+6% DMA, LPF-T+2% NMA, LPF-T+4% NMA, LPF-T+6% NMA. Sperm quality [sperm membrane integrity (SMI), motility and kinetic parameters] was assessed before and after cryopreservation. Fertility and embryo viability were recorded. Increasing both DMA and NMA concentration from 2 to 6% improved SMI, total motile sperm, progressive motile sperm (PMS), VCL, VSL and VAP values. PMS recovery rates were significantly the highest in 6% DMA, 4% NMA and 6% NMA treatments. Semen cryopreserved with DMA produced the best fertility and embryo viability at 6%; progressive lower values were recorded at lower concentrations, with no viable embryos at 2%. Semen cryopreserved with NMA showed the best fertility values at 2% and lower values were recorded at higher concentrations; live embryos were found in all NMA treatments. Finally, NMA and DMA showed a similar positive concentration dependent effect of the quality of cryopreserved semen. NMA, not DMA, provided the highest fertility and embryo viability values at the lowest 2%. Therefore, the use of NMA is recommended in order to reduce the cryoprotectant concentration, with a concomitant reduction in the risk of toxicity, providing at the same time the adequate cryoprotective action to obtain viable embryos after artificial insemination of cryopreserved chicken semen.


Asunto(s)
Criopreservación , Preservación de Semen , Acetamidas , Animales , Pollos , Criopreservación/métodos , Crioprotectores/farmacología , Fertilidad , Masculino , Semillas , Semen , Preservación de Semen/veterinaria , Motilidad Espermática , Espermatozoides , Trehalosa/farmacología
8.
J Card Surg ; 37(12): 4833-4840, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36403275

RESUMEN

BACKGROUND AND AIM: Bioprosthetic surgical aortic valve replacement (SAVR) is increasingly adopted in younger patients. We aimed to analyze mid-term follow-up data after SAVR to assess the performance of the prosthesis. METHODS: Data were collected from a single-center series of 154 patients, who underwent SAVR with a bioprosthetic heart valve with the RESILIA tissue at our Heart Centre in Siegburg. All procedural and midterm patient outcomes were documented. RESULTS: Patients had a mean age of 56.8 ± 9.9 years, 35.7% were female, and the mean logistic European system for cardiac operative risk evaluation (EuroSCORE) was 3.4 ± 3.6%. Diabetes (12.3%), atrial fibrillation (10.4%), and chronic obstructive pulmonary disease (COPD) (5.8%) were common comorbidities. The mean surgery duration was 163.8 ± 73.4 min, with the 23 mm (34.4%) and 25 mm (33.8%) heart valves being most frequently implanted. At 3-year follow-up, mean pressure gradient was 13.9 ± 5.9 mmHg, peak gradient was 23.6 ± 7.7 mmHg, and effective orifice area (EOA) was 1.9 ± 0.4 cm². No patient died during the operation, 3 (2.1%) patients within 30 days, and 4 (2.7%) thereafter with an overall mortality of n = 7. Of the surviving patients, 97.8% were in New York Heart Association (NYHA) class I/II and none had structural valve deterioration (SVD). CONCLUSION: Results of our single-center study indicate favorable procedural outcomes. The safety outcomes confirm preliminary earlier results of this novel bioprosthesis but include more patients and a longer midterm follow-up.


Asunto(s)
Estenosis de la Válvula Aórtica , Bioprótesis , Implantación de Prótesis de Válvulas Cardíacas , Prótesis Valvulares Cardíacas , Humanos , Femenino , Persona de Mediana Edad , Anciano , Masculino , Válvula Aórtica/cirugía , Implantación de Prótesis de Válvulas Cardíacas/métodos , Estenosis de la Válvula Aórtica/cirugía , Resultado del Tratamiento , Diseño de Prótesis
9.
Chemistry ; 26(29): 6686-6693, 2020 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-32203623

RESUMEN

Density functional studies of the edges of single-layer 1H-MoS2 are presented. This phase presents a rich variability of edges that can influence the morphology and properties of MoS2 nano-objects, play an important role in industrial chemical processes, and find future applications in energy storage, electronics and spintronics. The so-called Mo-100 %S edges vertical S-dimers were confirmed to be stable, however the authors also identified a family of metastable edges combining Mo atoms linked by two-electron donor symmetrical disulfide ligands and four-electron donor unsymmetrical disulfide ligands. These may be entropically favored, potentially stabilizing them at high temperatures as a "liquid edge" phase. For Mo-50 %S edges, S-bridge structures with 3× periodicity along the edge are the most stable, compatible with a Peierls' distortion arising from the d-bands of the edge Mo atoms. An additional explanation for this periodicity is proposed through the formation of 3-center bonds.

10.
Thorac Cardiovasc Surg ; 67(5): 345-350, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29605960

RESUMEN

OBJECTIVES: The optimal hypothermic level during circulatory arrest in aortic arch surgery remains controversial, particularly in frozen elephant trunk (FET) procedures. We describe herein our experience for total arch replacement with FET technique under moderate systemic hypothermic circulatory arrest (≥ 28°C) during selective antegrade cerebral perfusion. METHODS: Between January 2009 and January 2016, 38 consecutive patients underwent elective total arch replacement for various aortic arch pathologies with FET technique using the E-vita Open hybrid prosthesis (Jotec GmbH, Hechingen, Germany). Selective unilateral or bilateral cerebral perfusion under moderate systemic hypothermic circulatory arrest (28.7°C ± 0.5°C) was used in all patients. Minimally invasive total arch replacement with FET via partial upper sternotomy was performed in 15 patients (39%) and in the remaining 23 patients (61%) via full sternotomy. Mean late follow-up was 3 ± 2 years and was 98% complete. Clinical data were prospectively entered into our institutional database. RESULTS: Cardiopulmonary bypass time accounted for 198 ± 58 minutes and the myocardial ischemic time 109 ± 29 minutes. Selective antegrade cerebral perfusion time was 55 ± 6 minutes. Lower body circulatory arrest time was 39 ± 11 minutes. Unilateral cerebral perfusion was performed in 31 patients (82%), and bilateral in 7 patients (18%). Intensive care unit stay was 4 ± 3 days. Thirty-day mortality was 5% (n = 2). Late survival at 3 years was 87 ± 3%. Two patients (5%) required reexploration for bleeding. Patients were discharged after a hospital length of stay of 7 ± 2 days. Postoperative permanent neurologic complication occurred in two patients (5%). Three patients (8%) experienced a transient neurologic disorder. New transient renal replacement therapy was necessary in three patients (8%). No spinal cord injury was noted. CONCLUSIONS: Our data suggest that moderate systemic hypothermic circulatory arrest (≥ 28°C) in combination with antegrade cerebral perfusion can safely be applied for total aortic arch replacement with FET and offers sufficient neurologic and visceral organ protection.


Asunto(s)
Aorta Torácica/cirugía , Enfermedades de la Aorta/cirugía , Implantación de Prótesis Vascular/métodos , Circulación Cerebrovascular , Paro Cardíaco Inducido , Hipotermia Inducida , Perfusión , Anciano , Aorta Torácica/diagnóstico por imagen , Aorta Torácica/fisiopatología , Enfermedades de la Aorta/diagnóstico por imagen , Enfermedades de la Aorta/mortalidad , Enfermedades de la Aorta/fisiopatología , Prótesis Vascular , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/instrumentación , Implantación de Prótesis Vascular/mortalidad , Bases de Datos Factuales , Femenino , Paro Cardíaco Inducido/efectos adversos , Paro Cardíaco Inducido/mortalidad , Humanos , Hipotermia Inducida/efectos adversos , Hipotermia Inducida/mortalidad , Tiempo de Internación , Masculino , Persona de Mediana Edad , Perfusión/efectos adversos , Perfusión/mortalidad , Complicaciones Posoperatorias/mortalidad , Complicaciones Posoperatorias/cirugía , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
11.
Molecules ; 24(22)2019 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-31766120

RESUMEN

Excitotoxicity related to the dysfunction of the N-methyl-d-aspartate receptor (NMDAR) has been indicated to play an integral role in the pathophysiology of multiple disease states, including neurodegenerative disorders such as Parkinson's disease. There is a notable gap in the market for novel NMDAR antagonists, however current methods to analyse potential antagonists rely on indirect measurements of calcium flux and hazardous radioligand binding assays. Recently, a fluorescent NMDAR ligand, N-adamantan-1-yl-dimethylamino-1-naphthalenesulfonic acid, known as AM-DAN was developed by our group. Additional studies on this ligand is necessary to evaluate its potential as a biological tool in NMDAR research. Therefore, this study was aimed at conducting structural analyses, fluorescence experiments, high-accuracy NMDAR molecular modelling and NMDAR phencyclidine (PCP) site competition binding studies using AM-DAN. Results revealed that AM-DAN has appropriate structural properties, significant fluorescent ability in various solvents and is able to bind selectively and compete for the PCP-binding site of the NMDAR. Therefore, AM-DAN holds promise as a novel fluorescent ligand to measure the affinity of prospective drugs binding at the NMDAR PCP-site and may circumvent the use of radioligands.


Asunto(s)
Sitios de Unión , Unión Competitiva , Descubrimiento de Drogas , Ligandos , Modelos Moleculares , Receptores de N-Metil-D-Aspartato/química , Colorantes Fluorescentes , Conformación Molecular , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Estructura Molecular , Relación Estructura-Actividad
13.
Thorac Cardiovasc Surg ; 66(3): 215-221, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28780765

RESUMEN

OBJECTIVES: Surgery for acute type A aortic dissection (AAD) remains a surgical challenge with considerable risk of morbidity and mortality. Antegrade cerebral perfusion (ACP) has been popularized, offering a more physiologic method of brain perfusion during complex aortic arch repair, often necessary in setting of AAD. The safe limits of this approach under moderate-to-mild systemic hypothermic circulatory arrest (≥ 28°C) are yet to be defined. Thus, the current study investigates our clinical results after surgical treatment for AAD in patients with a selective ACP and systemic circulatory arrest time of ≥ 60 minutes in moderate-to-mild hypothermia (≥ 28°C). METHODS: Between January 2000 and April 2016, 63 consecutive patients underwent surgical treatment for AAD employing selective ACP during moderate-to-mild systemic hypothermia (≥ 28°C) with prolonged ACP and circulatory arrest times. Patients' mean age was 59 ± 15 years, and 39 patients (62%) were men. Hemiarch replacement and total arch replacement were performed in 13 (21%) and 50 (79%) patients, respectively. Frozen elephant trunk, arch light, and elephant trunk technique were performed in nine (14%), six (10%), and three patients (5%), respectively. Clinical data were prospectively entered into our institutional database. Mean late follow-up was 6 ± 4 years and was 98% complete. RESULTS: Cardiopulmonary bypass time accounted for 245 ± 81 minutes and the myocardial ischemic time accounted for 140 ± 43 minutes. Mean duration of ACP was 74 ± 12 minutes. The mean lowest core temperature accounted for 28.9 ± 0.8°C. Unilateral ACP was performed in 44 patients (70%); bilateral ACP was used in the remaining 19 patients (30%). Intensive care unit stay reached 6 ± 5 days. New onset of acute renal failure requiring hemofiltration was observed in 8% of patients (n = 5). New postoperative permanent neurologic deficits were found in five patients (8%) and transient neurologic deficits in six patients (10%). There was one case of paraplegia. Thirty-day mortality and in-hospital mortality were 8 (n = 5) and 11% (n = 7), respectively. Overall survival at 5 years was 76 ± 9%. CONCLUSION: Our preliminary data suggest that selective ACP during moderate-to-mild systemic hypothermic circulatory arrest (≥ 28°C) can safely be applied for more than 1 hour even in the setting of AAD.


Asunto(s)
Aneurisma de la Aorta/cirugía , Disección Aórtica/cirugía , Implantación de Prótesis Vascular/métodos , Circulación Cerebrovascular , Paro Cardíaco Inducido/métodos , Hipotermia Inducida/métodos , Tempo Operativo , Perfusión/métodos , Enfermedad Aguda , Adulto , Anciano , Disección Aórtica/diagnóstico por imagen , Disección Aórtica/fisiopatología , Aneurisma de la Aorta/diagnóstico por imagen , Aneurisma de la Aorta/mortalidad , Aneurisma de la Aorta/fisiopatología , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/mortalidad , Femenino , Paro Cardíaco Inducido/efectos adversos , Paro Cardíaco Inducido/mortalidad , Mortalidad Hospitalaria , Humanos , Hipotermia Inducida/efectos adversos , Hipotermia Inducida/mortalidad , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Perfusión/efectos adversos , Perfusión/mortalidad , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/mortalidad , Datos Preliminares , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
14.
J Sep Sci ; 39(22): 4449-4457, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27696671

RESUMEN

A new method is successfully developed for the separation and determination of a very low amount of tramadol in urine using functionalized multiwalled carbon nanotubes/flower-shaped zinc oxide before solid-phase microextraction combined with gas chromatography. Under ultrasonic agitation, a sol of multiwalled carbon nanotubes and flower-shaped zinc oxide were forced into and trapped within the pore structure of the polypropylene and the sol solution immobilized into the hollow fiber. Flower-shaped zinc oxide was synthesized and characterized by Fourier transform infrared spectroscopy. The morphology of the fabricated solid-phase microextraction surface was investigated by scanning electron microscopy and X-ray diffraction. The parameters affecting the extraction efficiencies were investigated and optimized. Under the optimized conditions, the method shows linearity in a wide range of 0.12-7680 ng/mL, and a low detection limit (S/N = 3) of 0.03 ng/mL. The precision of the method was determined and a relative standard deviation of 3.87% was obtained. This method was successfully applied for the separation and determination of tramadol in urine samples. The relative recovery percentage obtained for the spiked urine sample at 1000 ng/mL was 94.2%.


Asunto(s)
Nanotubos de Carbono , Microextracción en Fase Sólida , Tramadol/orina , Óxido de Zinc , Cromatografía de Gases , Humanos
15.
Cryobiology ; 73(3): 343-347, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27717656

RESUMEN

The aim of this study was to assess the combined effect of dimethylacetamide (DMA) and two non-permeating cryoprotective agents, trehalose and sucrose, on the quality of post-thaw chicken semen. Adult Lohmann roosters (n = 27) were used. Semen was processed according to the following treatments: Lake pre-freezing extender +6% DMA (LPF, control treatment), LPF + 0.1 M trehalose (LPF-T treatment), LPF + 0.1 M sucrose (LPF-S treatment) and LPF + 0.1 M trehalose + 0.1 M sucrose (LPF-TS treatment). Semen was loaded into straws and frozen in nitrogen vapour. Sperm quality (viability, mobility and kinetic parameters) was assessed immediately after thawing (T0) and at 5 (T5), 10 (T10) and 15 min (T15) thereafter. The different cryodiluent combinations significantly affected the kinetic parameters. The presence of trehalose, alone or with sucrose, combined with DMA improved the quality of motion in cryopreserved sperm in comparison to DMA alone (LPF) and DMA with sucrose (LPF-S). In particular, the highest values in linearity (LIN) and wobble (WOB) were measured in the treatment LPF-T. The treatments significantly affected the recovery rate of progressive motile sperm that presented the best value soon after thawing in the LPF-T treatment; moreover, the presence of trehalose, alone (LPF-T) or with sucrose (LPF-TS), significantly improved the recovery rate of progressive motile sperm also at T5 and T10 compared to LPF and LPF-S. The present results show a positive synergic action of DMA and trehalose on motile function of thawed chicken sperm.


Asunto(s)
Criopreservación/métodos , Crioprotectores/farmacología , Preservación de Semen/métodos , Motilidad Espermática/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Acetamidas/farmacología , Animales , Pollos , Congelación , Masculino , Semen/efectos de los fármacos , Sacarosa/farmacología , Trehalosa/farmacología
16.
Perfusion ; 30(4): 284-90, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25049285

RESUMEN

OBJECTIVE: Risk factors for adverse outcome after extracorporeal life support (ECLS) are yet to be defined. For this purpose, we reviewed our institutional data from more than a decade, focusing on patients with ECLS. METHODS: Between December 2001 and June 2013, 360 consecutive cardiac surgical patients received ECLS for post-cardiotomy cardiogenic shock, with high mortality risk despite optimal conventional therapy. Patient demographics, clinical characteristics, ECLS-related morbidity, as well as in-hospital and long-term mortality were analysed. Multivariate logistic regression analysis was performed to identify independent predictors of adverse outcome (failed ECLS weaning, in-hospital mortality). RESULTS: The mean age was 62±17 years, 76% were male and the mean preoperative ejection fraction was 35±16%. ECLS was established through peripheral (90%) or central thoracic cannulation. The mean duration of ECLS was 7±1 days. Intra-aortic balloon pumps were implanted in 22% of the patients. ECLS weaning was successful in 58% and 30% could be discharged from hospital. The main cause of death was sepsis (69%). Overall, major cerebrovascular events occurred in 12% (bleeding 3%, embolic 9%), limb ischaemia in 13%, gastrointestinal complications in 16% and renal replacement therapy in 61%. Independent risk factors for adverse outcome were prior cardiorespiratory resuscitation (OR: 4.1, 95%CI: 0.34-4.21, p=0.04), pH <7.1 (OR: 2.8, 95%CI: 0.45-3.28, p=0.01), serum lactate >120 mg/dL (OR: 2.6, 95%CI: 0.75-2.96, p< 0.01), norepinephrine dosage >0.5 µg/kg/min (OR: 2.4, 95%CI: 0.35-2.92, p=0.02) and age >75 years (OR: 2.0, 95%CI: 0.41-2.88, p=0.02). Kaplan Meier estimates for long-term survival were 26±3% at one year and 22±2% at five years. CONCLUSION: ECLS therapy offers one-year survival to one quarter of patients with an otherwise fatal prognosis. Procedural mortality is low and morbidity at the implantation site typically moderate. Thus, prolonged metabolic deterioration in combination with high-dose vasopressor support prior to ECLS therapy should be avoided, particularly in younger patients.


Asunto(s)
Circulación Extracorporea/efectos adversos , Mortalidad Hospitalaria , Complicaciones Posoperatorias/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Concentración de Iones de Hidrógeno , Ácido Láctico/sangre , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/sangre , Complicaciones Posoperatorias/fisiopatología , Estudios Retrospectivos , Factores de Riesgo , Volumen Sistólico , Tasa de Supervivencia
17.
ACS Appl Mater Interfaces ; 16(25): 32857-32873, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38865590

RESUMEN

This study demonstrates that the electrochemical doping of lanthanum nickelate (LNO) with cobalt ions is a promising strategy for enhancing its physical and electrochemical properties, which are critical for energy storage and conversion devices. LNO emerges as a promising hole transport layer (HTL) in solar cells due to its stability, large band gap, and high transparency. Nevertheless, its low conductivity and improperly aligned band positions are persistent problems. Here, in a pioneering endeavor, Co-doped LNO thin films were synthesized electrochemically and applied as the HTL in polymer solar cells (PSCs). Characterization revealed the impact of Co doping on the electrochemical, structural, morphological, and optical properties of LNO thin films. Depending on the Co doping level, PSCs based on 10 mol % Co-doped LNO outperformed pure LNO, achieving a champion efficiency of 6.11% with enhanced short-circuit current density (12.84 mA cm-2), fill factor (68%), open-circuit voltage (0.70 V), and external quantum efficiency (82.6%). This enhancement resulted from decreased series resistance, refined surface morphology, minimized trap-assisted recombination, enhanced conductivity, increased charge carrier production, favorable energy level alignment, and improved current extraction facilitated by LNC0.10O HTL. Moreover, the unencapsulated PSC-LNC0.10O long-term stability notably improved and retained 86% of its initial PCE after 450 h storage in ambient air, 82% after being continuously heated to 85 °C for 300 h, and 80% after operating at maximum power point for 300 h. These findings offer a straightforward approach to enhancing PSC performance through Co doping of LNO, supported by density functional theory (DFT) calculations that validate the experimental results and confirm the improvement in optical properties and stability of PSCs as an HTL.

18.
Artículo en Inglés | MEDLINE | ID: mdl-38696749

RESUMEN

OBJECTIVES: Patients with failed stentless aortic prostheses are a challenging population to treat, as reoperative procedures may be complex and catheter-based treatments are associated with a high rate of procedural events. Reoperative surgery using sutureless valves may be an alternative. METHODS: In this multicentre experience, we assess outcomes of 17 patients who underwent reoperative surgery using the Perceval valve (Corcym UK Limited, London, UK) inside Freestyle prosthesis (Medtronic Inc., Dublin, Ireland) or bioroots from 2018 to 2023. RESULTS: Mean age was 71.1 ± standard deviation 15.1 years and mean EuroSCORE II was 13.5 ± 15.8%, Society of Thoracic Surgeons Score was 5.9 ± 11.7%. Mean transvalvular gradient at baseline was 25.3 ± 19.9 mmHg and left ventricular ejection fraction was 53.5 ± standard deviation 8.5%. In 70.6% (12/17), moderate or severe aortic regurgitation was present. Implant success was 100%. Aortic cross-clamp time was 44.5 ± standard deviation 23.6 min. No patient needed a pacemaker and no mild paravalvular regurgitation occurred. Mean gradient was 12.5 ± 4.7 mmHg; 30-day mortality was 5.9% (1/17). CONCLUSIONS: Rate of mortality was lower than predicted by EuroSCORE II in these high-risk patients and haemodynamic outcomes were favourable. Heart teams should consider this treatment concept when discussing patients with failed stentless valves or bioroots.

19.
J Clin Med ; 13(11)2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38892869

RESUMEN

Background/Objectives: The minimally invasive approach through left mini-thoracotomy is a promising alternative to the median sternotomy for coronary artery bypass. The aim of this study was to compare the short-term outcomes of patients undergoing minimally invasive coronary artery bypass (MIDCAB) with off-pump coronary artery bypass through sternotomy (OPCAB) for single-vessel disease. Methods: From January 2017 to February 2023, 377 consecutive patients aged above 18 years undergoing off-pump bypass of the left anterior descending artery (LAD) with left internal thoracic artery underwent OPCAB. Propensity score matching was then applied. Primary endpoints were in-hospital mortality and 30-day mortality. Results: Prior to matching, 30-day mortality occurred in 2 (0.7%) patients in the MIDCAB group vs. 1 (1%) patient in the OPCAP group (p = 1). Transfusion of red blood cells (RBC) was required in 9.4% and 29% of patients within the MIDCAB and the OPCAB groups, respectively (p < 0.001). Median intensive care stay (ICU) was 1 [1-2] day in the MIDCAB group, vs. 2 [1-3] in the OPCAB (p < 0.001). In the matched cohort, 10% of MIDCAB patients received RBCs vs. 27.5% of OPCAB patients (p = 0.006). Median ICU stay was significantly lower in the MIDCAB group, 1 [1-2] vs. 2 [1-3] days. Conclusions: MIDCAB is as safe and effective as OPCAB for single coronary artery bypass of the LAD with the LITA in select patients. It is associated with a decreased ICU stay and lower transfusion rates when compared with OPCAB.

20.
Artículo en Inglés | MEDLINE | ID: mdl-38830025

RESUMEN

OBJECTIVES: To overcome some of the challenges of endoscopic minimally invasive valve surgery, an automated annular suturing device has been used in aortic and mitral valve replacement surgeries. The current study investigates early clinical outcomes of patients who received aortic or mitral valve replacement with the help of the RAM® device as first experiences in minimally invasive valve surgery. METHODS: Between September 2020 and June 2023, 66 consecutive patients (mean age 61.8 ± 11 years) underwent endoscopic minimally invasive aortic or mitral valve replacement through right anterior mini-thoracotomy at 2 cardiac surgery referral centres in Germany. The RAM® device was used in all Patients. 3.5 and 5.0 sizes were used in 16.7% and 83.3% of patients, respectively. Aortic, mitral and double valve surgery was performed in 81.8%, 15.2% and 1.5% of patients, respectively. Clinical data were prospectively entered into our institutional database. RESULTS: Cardiopulmonary bypass time and cross-clamping time were 97.9 ± 20.9 and 66 ± 15.7 min, respectively. Intensive care unit and hospital stays were 1 [1-2] and 9 [7-13] days, respectively. No paravalvular leak and no other intraoperative complications occurred. 30-day and in-hospital mortality were zero. Conversion to sternotomy occurred in 1 (1.5%) patient due to bleeding. CONCLUSIONS: The usage of the RAM® device is a safe, feasible and effective approach to the endoscopic implantation of aortic or mitral valves and yield excellent early outcomes. Larger size studies are needed to evaluate the efficacy and safety of RAM® device.

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