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1.
J Cardiothorac Vasc Anesth ; 38(1): 73-79, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37953174

ABSTRACT

OBJECTIVES: Anemia and transfusion are common in cardiac surgery patients, and are associated with significant morbidity and mortality. Multiple perioperative interventions have been described to reduce blood transfusion, but are rarely combined altogether. The aim of this study was to compare the incidence of red blood cell (RBC) transfusion in adult patients undergoing cardiac surgery before and after the implementation of a perioperative patient blood management (PBM) program. DESIGN: Before-and-after observational study. SETTING: Single-center French university teaching hospital. PARTICIPANTS: Adult patients scheduled for cardiac surgery. INTERVENTIONS: Perioperative patient blood management program including pre-, intra-, and postoperative interventions aimed at identifying and correcting anemia, minimizing blood loss during surgery, and optimizing coagulation. MEASUREMENTS AND MAIN RESULTS: Four hundred thirty-four patients were included in the study from January 2021 to July 2022. The incidence of perioperative RBC transfusion (intraoperatively and during the first 2 postoperative days) was significantly reduced from 43% (90/213) in the pre-PBM period to 27% (60/221) in the post-PBM period (p < 0.001). The application of a PBM program was associated with a reduction in perioperative RBC transfusion by multivariate analysis (odds ratio 0.55, 95% CI 0.36-0.85, p = 0.007), and was associated with a reduction in the median number of RBC units transfused within transfused patients (p = 0.025). These effects persisted at day 30 after surgery (p = 0.029). CONCLUSION: A perioperative PBM program in adult patients undergoing cardiac surgery was associated with a significant reduction in perioperative RBC transfusion, which persisted at day 30.


Subject(s)
Anemia , Cardiac Surgical Procedures , Adult , Humans , Erythrocyte Transfusion , Blood Transfusion , Cardiac Surgical Procedures/adverse effects , Hospitals, University
2.
Chaos ; 27(11): 114321, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29195319

ABSTRACT

The Mackey-Glass equation is the representative example of delay induced chaotic behavior. Here, we propose various control mechanisms so that otherwise erratic solutions are forced to converge to the positive equilibrium or to a periodic orbit oscillating around that equilibrium. We take advantage of some recent results of the delay differential literature, when a sufficiently large domain of the phase space has been shown to be attractive and invariant, where the system is governed by monotone delayed feedback and chaos is not possible due to some Poincaré-Bendixson type results. We systematically investigate what control mechanisms are suitable to drive the system into such a situation and prove that constant perturbation, proportional feedback control, Pyragas control, and state dependent delay control can all be efficient to control Mackey-Glass chaos with properly chosen control parameters.

3.
Ideggyogy Sz ; 68(3-4): 93-8, 2015 Mar 30.
Article in Hungarian | MEDLINE | ID: mdl-26434196

ABSTRACT

Neuropathic pain is considered as a special type of different pain conditions. It's pathophysiological basis and treatment is completely different from the nociceptive pain. The first comprehensive therapeutic guidelines published approximately a decade ago recommended tricyclic antidepressants, anticonvulsants and opioids. The recent summary presents and evaluates national and international guidelines issued in the last five years. The most frequently suggested drugs by all guidelines are amitriptyline, duloxetine, gabapentin and pregabalin. Pregabalin is the only drug that is recommended first line in all guidelines referred. Opioids are in the second or third line. There seems to be no major development in the pharmacological treatment of the neuropathic pain compared to the earlier recommendations. High quality studies of head to head comparisons and effectiveness of combination therapy are still lacking.


Subject(s)
Analgesics, Non-Narcotic/therapeutic use , Analgesics, Opioid/therapeutic use , Neuralgia/drug therapy , Amines/therapeutic use , Amitriptyline/therapeutic use , Anticonvulsants/therapeutic use , Antidepressive Agents/therapeutic use , Antidepressive Agents, Tricyclic/therapeutic use , Cyclohexanecarboxylic Acids/therapeutic use , Duloxetine Hydrochloride , Gabapentin , Humans , Neuralgia/physiopathology , Practice Guidelines as Topic , Pregabalin , Thiophenes/therapeutic use , gamma-Aminobutyric Acid/analogs & derivatives , gamma-Aminobutyric Acid/therapeutic use
4.
J Craniofac Surg ; 25(3): 1062-7, 2014 May.
Article in English | MEDLINE | ID: mdl-24657978

ABSTRACT

In the present work, surface analytical investigation of unimplanted as well as retrieved pyrolytic carbon-covered carbon/carbon composite implants and Ti osteosynthesis plates is reported. The Ti plates were covered by a 200-nm-thick, anodically and thermally formed TiO2 layer. Our results suggest that although the oxide layer on the Ti miniplates remained stable during the time spent in the human body, there is still material transport between the implant and the human body. In case of the carbon/carbon composite implants, damage of the carbon fibers constituting the material was found on one side of the sterile implant and attributed to the manufacturing process. The NaCl crystals originally present on the surface of the sterile material disappeared during the time spent in the human body. As a result of the interaction with the human body, a new surface layer (mainly constituted of carbon) appeared on the implant. The results indicate that both the time spent in the human organism and the preparation of the implants before operation can have detectable effects on the investigated surface properties. Surface analytical investigations could therefore provide information not only about the biocompatibility of these materials but also about the effect of their treatment before operation.


Subject(s)
Bone Plates , Carbon/chemistry , Coated Materials, Biocompatible/chemistry , Maxillofacial Prosthesis/standards , Surface Properties , Titanium/chemistry , Carbon Fiber , Device Removal , Fracture Fixation, Internal/methods , Humans , Materials Testing/methods , Oxidation-Reduction
5.
J Mater Sci Mater Med ; 24(3): 821-8, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23274629

ABSTRACT

The long term effect of the human body on a pyrolytic carbon covered C/C composite maxillofacial implant (CarBulat(Tm)) was investigated by comparing the structure, the surface morphology and composition of an implant retrieved after 8 years to a sterilized, but not implanted one. Although the thickness of the carbon fibres constituting the implants did not change during the 8 year period, the surface of the implant retrieved was covered with a thin surface layer not present on the unimplanted implant. The composition of this layer is identical to the composition of the underlying carbon fibres. Calcium can only be detected on the surface as a trace element implying that the new layer is not formed by bone tissue. Residual soft tissue penetrating the bulk material between the carbon fibre bunches was found on the retrieved implant indicating the importance of the surface morphology in tissue growth and adhering to implants.


Subject(s)
Carbon , Maxillofacial Prosthesis , Microscopy, Electron, Scanning/methods , Spectrometry, X-Ray Emission/methods , Humans
6.
Nanomaterials (Basel) ; 13(3)2023 Jan 27.
Article in English | MEDLINE | ID: mdl-36770473

ABSTRACT

Our research group developed a novel nano-pitted (NP) TiO2 surface on grade 2 titanium that showed good mechanical, osteogenic, and antibacterial properties; however, it showed weak hydrophilicity. Our objective was to develop a surface treatment method to enhance the hydrophilicity of the NP TiO2 surface without the destruction of the nano-topography. The effects of dilute and concentrated orthophosphoric (H3PO4) and nitric acids were investigated on wettability using contact angle measurement. Optical profilometry and atomic force microscopy were used for surface roughness measurement. The chemical composition of the TiO2 surface and the oxidation state of Ti was investigated using X-ray photoelectron spectroscopy. The ccH3PO4 treatment significantly increased the wettability of the NP TiO2 surfaces (30°) compared to the untreated control (88°). The quantity of the absorbed phosphorus significantly increased following ccH3PO4 treatment compared to the control and caused the oxidation state of titanium to decrease (Ti4+ → Ti3+). Owing to its simplicity and robustness the presented surface treatment method may be utilized in the industrial-scale manufacturing of titanium implants.

7.
Orv Hetil ; 153(19): 744-50, 2012 May 13.
Article in Hungarian | MEDLINE | ID: mdl-22564286

ABSTRACT

In their previous report, the authors presented observations regarding the long-term application of carbon/carbon implants. After evaluating the good functional and aesthetic results, the effect of the human body on the structure and morphology of the implants was investigated with state of the art methods. An implant retrieved from the body after eight years was compared to implants which were sterilized but not implanted (reference). Carbon and oxygen were the main components of both implants, however, as a result of the interaction with the human body the amount of oxygen increased 3-4 times and phosphorus, sulphur, calcium and iron were detectable as trace elements on the surface. The width of the carbon fibres (5-7 µm) building up the implants was not changed during the interaction with the human body. The surface of the implant retrieved from the human body was covered with a 15-17 µm thick layer, not present on the reference implant, having a similar composition to that of the carbon fibres (high amount of calcium that is typical to bone tissue was not detected). According to these results, the structure and the morphology of the implants were not altered notably by the human body.


Subject(s)
Biocompatible Materials , Carbon , Mandible , Prostheses and Implants , Surface Properties , Carbon Fiber , Humans , Mandible/surgery , Oral Surgical Procedures/methods , Time Factors
8.
Front Psychiatry ; 13: 879896, 2022.
Article in English | MEDLINE | ID: mdl-35990073

ABSTRACT

Depression is a growing problem worldwide, impacting on an increasing number of patients, and also affecting health systems and the global economy. The most common diagnostical rating scales of depression are self-reported or clinician-administered, which differ in the symptoms that they are sampling. Speech is a promising biomarker in the diagnostical assessment of depression, due to non-invasiveness and cost and time efficiency. In our study, we try to achieve a more accurate, sensitive model for determining depression based on speech processing. Regression and classification models were also developed using a machine learning method. During the research, we had access to a large speech database that includes speech samples from depressed and healthy subjects. The database contains the Beck Depression Inventory (BDI) score of each subject and the Hamilton Rating Scale for Depression (HAMD) score of 20% of the subjects. This fact provided an opportunity to compare the usefulness of BDI and HAMD for training models of automatic recognition of depression based on speech signal processing. We found that the estimated values of the acoustic model trained on BDI scores are closer to HAMD assessment than to the BDI scores, and the partial application of HAMD scores instead of BDI scores in training improves the accuracy of automatic recognition of depression.

9.
Materials (Basel) ; 15(19)2022 Oct 04.
Article in English | MEDLINE | ID: mdl-36234226

ABSTRACT

The adsorption technique is widely used in water purification, and its efficiency can be significantly improved by target-specific adsorbent design. Research on iodine and its ion removal from water has attracted a great deal of interest due to increased concentrations in the environment and acute toxic effects, e.g., in human thyroid cells. In this work, the iodide removal performance of two high-surface-area resorcinol-formaldehyde-based carbon aerogels was studied under acidic conditions. The BET surface area was 790 m2/g (RF_ac) and 375 m2/g (RMF-GO), with a corresponding micropore ratio of 36 and 26%, respectively. Both aerogels showed outstanding adsorption capacity, exceeding the reported performance of other carbons and Ag-doped materials. Owing to its basic nature, the RMF-GO carbon aerogel showed higher I- capacity, up to 97 mg/g, than the acidic RF_ac, which reached a capacity of 82 mg/g. The surface chemistry of the aerogels also played a distinct role in the removal. In terms of kinetics, RF_ac removed 60% of the iodide ions and RMF-GO 30% within 8 h. The removal kinetics was of the first order, with a half-life of 1.94 and 1.70 h, respectively.

10.
Materials (Basel) ; 14(13)2021 Jun 23.
Article in English | MEDLINE | ID: mdl-34201568

ABSTRACT

In this paper we report the synthesis of a N, S co-doped metal free carbon cryogel obtained from a marine biomass derived precursor using urea as nitrogen source. Natural carrageenan intrinsically contains S and inorganic salt. The latter also serves as an activating agent during the pyrolytic step. The overall 11.6 atomic % surface heteroatom concentration comprises 5% O, 4.6% N and 1% S. The purified and annealed final carbon (CA) has a hierarchical pore structure of micro-, meso- and macropores with an apparent surface area of 1070 m2/g. No further treatment was applied. The gas adsorption potential of the samples was probed with H2, CO2 and CH4, while the electrocatalytic properties were tested in an oxygen reduction reaction. The atmospheric CO2 and CH4 storage capacity at 0 °C in the low pressure range is very similar to that of HKUST-1, with the CO2/CH4 selectivity below 20 bar, even exceeding that of the MOF, indicating the potential of CA in biogas separation. The electrocatalytic behavior was assessed in an aqueous KOH medium. The observed specific gravimetric capacitance 377 F/g was exceeded only in B, N dual doped and/or graphene doped carbons from among metal free electrode materials. The CA electrode displays almost the same performance as a commercial 20 wt% Pt/C electrode. The oxygen reduction reaction (ORR) exhibits the 4-electron mechanism. The 500-cycle preliminary stability test showed only a slight increase of the surface charge.

11.
Thorac Surg Clin ; 30(1): 1-13, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31761277

ABSTRACT

Nonintubated thoracic surgery (NITS) has a good safety record in experienced hands, but has pitfalls for beginners. The main aim of NITS is to keep the patient under spontaneous respiration, avoiding adverse effects, such as hypoxemia, hypercapnia, panic attacks, and finally conversion to general anesthesia. In this paper, the safety aspects of anesthesia for NITS is discussed based on data from the literature and personnel clinical experiences.


Subject(s)
Anesthesia, General/methods , Patient Safety , Postoperative Complications/prevention & control , Thoracic Surgical Procedures , Anesthesia, Epidural/methods , Humans , Monitoring, Intraoperative/methods , Panic Disorder/prevention & control , Thoracic Surgical Procedures/adverse effects , Thoracic Surgical Procedures/methods , Thoracic Surgical Procedures/psychology
12.
J Chem Theory Comput ; 16(9): 5736-5746, 2020 Sep 08.
Article in English | MEDLINE | ID: mdl-32709204

ABSTRACT

Molten alkali-metal carbonates and hydroxides play important roles in the molten carbonate fuel cell and in Earth's geochemistry. Molecular simulations allow us to study these systems at extreme conditions without the need for difficult experimentation. Using a genetic algorithm to fit ab intio molecular dynamics-computed densities and radial distribution functions, as well as experimental enthalpies of formation, we derive new classical force fields able to accurately predict liquid chemical potentials. These fitting properties were chosen to ensure accurate liquid phase structure and energetics. Although the predicted dynamics is slow when compared to experiments, in general the trends in dynamic properties across different systems still hold true. In addition, these newly parametrized force fields can be extended to the molten carbonate-hydroxide mixtures by using standard combining rules.

13.
Anal Bioanal Chem ; 393(8): 1843-56, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19294368

ABSTRACT

Metal hydrides are one of the most promising technologies in the field of hydrogen storage due to their high volumetric storage density. Important reaction steps take place at the very surface of the solid during hydrogen absorption. Since these reaction steps are drastically influenced by the properties and potential contamination of the solid, it is very important to understand the characteristics of the surface, and a variety of analytical methods are required to achieve this. In this work, a TiMn(2)-type metal hydride alloy is investigated by means of high-pressure activation measurements, X-ray photoelectron spectroscopy (XPS), secondary neutral mass spectrometry (SNMS) and thermal desorption mass spectrometry (TDMS). In particular, TDMS is an analytical tool that, in contrast to SIMS or SNMS, allows the hydrogen content in a metal to be quantified. Furthermore, it allows the activation energy for desorption to be determined from TDMS profiles; the method used to achieve this is presented here in detail. In the results section, it is shown that the oxide layer formed during manufacture and long-term storage prevents any hydrogen from being absorbed, and so an activation process is required. XPS measurements show the oxide states of the main alloy elements, and a layer 18 nm thick is determined via SNMS. Furthermore, defined oxide layers are produced and characterized in UHV using XPS. The influence of these thin oxide layers on the hydrogen sorption process is examined using TDMS. Finally, the activation energy of desorption is determined for the investigated alloy using the method presented here, and values of 46 kJ/mol for hydrogen sorbed in UHV and 103 kJ/mol for hydrogen originating from the manufacturing process are obtained.

14.
Anal Bioanal Chem ; 390(6): 1495-505, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18210095

ABSTRACT

Hydrogen storage in metal hydrides is a promising alternative to common storage methods. The surface of a metal hydride plays an important part in the absorption of hydrogen, since important partial reaction steps take place here. The development of surface contaminations and their influence on hydrogen absorption is examined by means of absorption experiments and surface analysis, using X-ray photoelectron spectroscopy (XPS), thermal desorption mass spectrometry (TDMS) and secondary neutral mass spectrometry (SNMS), in this work. All investigations were carried out on a modern AB(2) metal hydride alloy, namely Ti(0.96)Zr(0.04)Mn(1.43)V(0.45)Fe(0.08). Surface analysis (SNMS, XPS) shows that long-term air storage (several months) leads to oxide layers about 15 nm thick, with complete oxidation of all main alloy components. By means of in situ oxygen exposure at room temperature and XPS analysis, it can be shown that an oxygen dose of about 100 Langmuirs produces an oxide layer comparable to that after air storage. Manganese enrichment (segregation) is also clearly observed and is theoretically described here. This oxide layer hinders hydrogen absorption, so an activation procedure is necessary in order to use the full capacity of the metal hydride. This procedure consists of heating (T = 120 degrees C) in vacuum and hydrogen flushing at pressures like p = 18 bar. During the activation process the alloy is pulverized to particles of approximately 20 microm through lattice stretches. It is shown that this pulverization of the metal hydride (creating clean surface) during hydrogen flushing is essential for complete activation of the material. Re-activation of powder contaminated by small doses of air (p approximately 0.1 bar) does not lead to full absorption capacity. In ultrahigh vacuum, hydrogen is only taken up by the alloy after sputtering of the surface (which is done in order to remove oxide layers from it), thus creating adsorption sites for the hydrogen. This is shown by TDMS measurements with and without sputtering and oxygen exposure.

15.
A A Pract ; 10(6): 144-147, 2018 Mar 15.
Article in English | MEDLINE | ID: mdl-29095710

ABSTRACT

A 19-year-old man with mitral valve endocarditis and prolapse, intracerebral and intracerebellar hematoma, and a mycotic cerebral aneurysm underwent emergency mitral valve replacement during minimal cardiopulmonary bypass (total priming volume, 800 mL; autologous retropriming, activated clotting time <300 seconds) 1 day after undergoing endovascular coil embolization of the aneurysm. Postoperatively, there were no extensions of the intracerebral and intracerebellar hematoma. After intensive rehabilitation therapy, the patient recovered fully except for residual bilateral claudication because of preoperative bilateral embolism to both superficial femoral arteries.

16.
Nanoscale ; 10(41): 19290-19296, 2018 Nov 07.
Article in English | MEDLINE | ID: mdl-30325385

ABSTRACT

The dynamical aspects of bipolar resistive switchings have been investigated in Nb/Nb2O5/PtIr nanojunctions. We found that the widely tuneable ON and OFF state resistances are well separated at low bias. On the other hand, the high-bias regime of the resistive switchings coincides with the onset of a high nonlinearity in the current-voltage characteristics, where the impedance of both states rapidly decreases and becomes equivalent around 50 Ω. This phenomenon enables the overriding of the RC limitations of fast switchings between higher resistance ON and OFF states. Consequently, nanosecond switching times between multiple resistance states due to subnanosecond voltage pulses are demonstrated. Moreover, this finding provides the possibility of impedance engineering by the appropriate choice of voltage signals, which facilitates that both the set and reset transitions take place in an impedance matched manner to the surrounding circuit, demonstrating the merits of ultra-fast operation of Nb2O5 based neuromorphic networks.

18.
Orv Hetil ; 147(18): 833-9, 2006 May 07.
Article in Hungarian | MEDLINE | ID: mdl-16784138

ABSTRACT

INTRODUCTION: It is well known that the vibrating tools used by the miners can cause hand-arm vibration syndrome. However no detailed reports on this field could be found in the Hungarian literature. AIM: The aim of this study was to clarify the clinical features of the hand-arm vibration syndrome of the miners. METHOD: The circulation, the peripheral nerves and the osteoarticular system of the upper extremities of 152 miners were examined by means of cold provocation test, Allen-test, measurement of systolic blood pressure performed by Doppler flowmeter, clinical neurological and neurographic examination and X-ray investigation of the bones and joints. RESULTS: Hand-arm vibration syndrome was diagnosed in 87 patients (57.2%). The most common symptom was the lesion of the circulation which occurred in 78 patients (89.6%). The peripheral nerves were affected in 44 cases (50.5%). Radiological alteration of the bones and joints of the upper extremities was observed in 32 patients (36.8%). Out of 78 damaged cases the frequency of the vascular diseases was as follows: angiopathy (diminished systolic blood pressure in the fingers): 66 patient (84.6%), occlusion of the hand arteries (positive Allen-test) and arterial form of the thoracic outlet syndrome (positive elevation-test) respectively: 28 and 28 cases (35.9%), Raynaud phenomenon (positive cold-provocation test): 26 cases (33.3%). The peripheral nerves were examined in detail in 141 cases. Pathological alterations were observed in 78 patients (55.3%) in the following forms: carpal tunnel syndrome: 66 cases (84.6%), peripheral neuropathy of the upper limbs: 20 patients (25.6%), lesion of the ulnar nerve: 3 cases (3.8%), brachial plexus lesion: one patient (1.3%). Radiological alteration was most common in the carpal region (87 cases, 57.2%). The frequency of the lesion of cubital (40.4%) and shoulder region (40.7%) was practically the same. In the carpal region the most common alterations were the degenerative processes (23 cases, 15.1%) followed by the aseptic osteonecroses (22 patients, 14.5%). In the cubital region the periarticular changes (31 patients, 23.9%) were most common followed by degenerative changes (21 cases, 16.2%) and the osteochondrosis dissecans (13 cases, 10.1%). In the shoulder region the degenerative processes were the most common changes (41 patients, 34.7%), first of all in the acromioclavicular joint (21 cases, 17.8%). Aseptic necrosis was observed in two patients. CONCLUSIONS: The miners are professionally exposed not only to hand-arm vibration, but also to increased physical stress. The symptoms on the upper limbs can develop as the result of both exposures.


Subject(s)
Cumulative Trauma Disorders/etiology , Mining , Occupational Diseases/etiology , Occupational Exposure/adverse effects , Upper Extremity/physiopathology , Vibration , Adult , Aged , Arm , Blood Vessels/physiopathology , Bone and Bones/physiopathology , Cumulative Trauma Disorders/physiopathology , Hand , Humans , Hungary/epidemiology , Joint Diseases/epidemiology , Joint Diseases/etiology , Male , Middle Aged , Occupational Diseases/physiopathology , Osteoporosis/epidemiology , Osteoporosis/etiology , Peripheral Nerves/physiopathology , Peripheral Nervous System Diseases/epidemiology , Peripheral Nervous System Diseases/etiology , Peripheral Vascular Diseases/epidemiology , Peripheral Vascular Diseases/etiology , Regional Blood Flow , Syndrome , Upper Extremity/injuries
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