Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 48
Filter
1.
Chinese Journal of Medical Instrumentation ; (6): 294-297, 2023.
Article in Chinese | WPRIM | ID: wpr-982231

ABSTRACT

Oxygen therapy is an effective clinical method for the treatment of respiratory disorders, oxygen concentrator as a necessary medical auxiliary equipment in hospitals, its research and development has been a hot spot. The study reviewed the development history of the ventilator, introduced the two preparation technique of the oxygen generator pressure swing absorption (PSA) and vacuum pressure swing adsorption (VPSA), and analyzed the core technology development of the oxygen generator. In addition, the study compared some major brands of oxygen concentrators on the market and prospected the development trend of oxygen concentrators.


Subject(s)
Oxygen , Oxygen Inhalation Therapy , Hospitals , Ventilators, Mechanical , Equipment Design
2.
Article | IMSEAR | ID: sea-225666

ABSTRACT

Background: The association of combustive emission has been inter-related with haematologic parameters and a likelihoodto pro-inflammatory state. This research is aimed at assessing the impact of vehicular emission on erythrocyte level and red cell indices of occupationally exposed subjects.Methods:The level of haemoglobin concentration, haematocrit, red blood cells, mean cell volume, mean cell haemoglobin, mean cell haemoglobin concentration, and red cell distribution width were determined in four hundred subjects with the aid of Mythic 22 haematology autoanalyser.Results:The comparison of the haemoglobin and haematocrit shows that the value of mean ± standard error value of generator exposed and mechanics respectively were significantly higher than the other groups (p< 0.03). On the otherhand, the red blood cell count for generator exposed and mechanics ranked higherthan the other groups (p< 0.03). The mean cell volume (MCV) of generator exposed and mechanics were 86.57±0.08 fl and 84.49±1.04 fl respectively while control and drivers had values of 93.24±1.13 fl and 93.22±1.13 fl respectively (p< 0.03). The mechanics recorded a mean cell haemoglobin (MCH) of 26.92±0.40 pg which was significantly lower (p< 0.04) than the control (30.37±0.47 pg), generator exposed (39.68±6.38 pg) and drivers (30.42±0.47 pg). Conclusion:The differences amongst the groups and none of the groups were within the medically acceptable ranges which is a pointer to the fact that there might be an underlying inflammatory condition which might be due to occupational exposure

3.
Chinese Journal of Medical Instrumentation ; (6): 702-705, 2021.
Article in Chinese | WPRIM | ID: wpr-922087

ABSTRACT

The article describes the failure phenomenon, analysis and processing process of the high-voltage generator module, FRC unit, rack tilt circuit and slip ring system in the daily use of Philips Ingenuity CT, so as to sum up the experience, discuss with the medical staff, and further Deepen the understanding of Philips Ingenuity CT's structure and working principle, and jointly improve the maintenance skills of CT and other large equipments.


Subject(s)
Humans , Tomography, X-Ray Computed
4.
Journal of Medical Biomechanics ; (6): E528-E533, 2021.
Article in Chinese | WPRIM | ID: wpr-904433

ABSTRACT

Objective To investigate the effect from circumferential distribution angle of forwards wedge vortex generators on aerodynamic drag reduction during flow around a cylinder, so as to provide theoretical evidences for low drag sprint garment design. Methods Forwards wedge vortex generators were reconstructed based on the NIKE’s AeroBalde. Given that the individual parts of an athlete body can be treated as multiple cylinders with varied dimensions and positions, 48 forwards wedge vortex generators were distributed as four columns on windward side of the cylinder, which were symmetrical with the YOZ plane. When the air flowed through the cylinder at the speed of 32 km/h, large eddy simulation was carried out on the computational domains which were properly meshed with polyhedral mesh to investigate the drag force, flow filed and pressure distributions. Results It was effective for drag reduction of the cylinder induced by airflow when two columns of forwards wedge vortex generators were circumferential distributed in the range of 55°-75°and the circumferential internal angle between two columns was in the range of 10° or 15°. The pressure distribution on leeward side of the cylinder was apparently changed after surface modification, which minimized the pressure drag dominant in aerodynamic drag. The drag reduction mechanism was that micro-vortices were generated downstream after flow through the forwards wedge vortex generators, which resulted in an early transition to critical flow with low drag force. Conclusions Effective aerodynamic drag reduction is achieved if forwards wedge vortex generators are properly distributed. The research findings can provide guidance for wind tunnel test and low drag sprint garment design.

5.
Rev. Ciênc. Méd. Biol. (Impr.) ; 19(3): 485-488, dez 5, 2020. fig, tab
Article in Portuguese | LILACS | ID: biblio-1358018

ABSTRACT

Introdução: este estudo trata do controle de qualidade do radiofármaco utilizado em estudos de PET-CT para diagnóstico e/ou estadiamento de pacientes acometidos pelo câncer de próstata. Objetivo: avaliar a qualidade do radiofármaco PSMA-11, marcado com uso de gerador de Ge68-Ga68 itinerante. Metodologia: análise do aspecto visual, pH e pureza radioquímica do radiofármaco marcado a cada recebimento do gerador de Ge68-Ga68. Resultado: todas as marcações realizadas se apresentaram límpidas quanto ao aspecto visual, o pH ficou entre 5,0 e 6,0 e a pureza radioquímica apresentou em 92% dos casos valores ≥ 96%. Conclusão: com os devidos controles de qualidade, pode ser uma opção para uso na clínica médica, em serviços que não disponham de condição para adquirir um sistema, por ser importado.


Introduction: this study works with the quality control of the radiopharmaceutical used in PET-CT studies for diagnosis and / or staging of patients affected with prostate cancer. Objective: evaluate the quality of the PSMA-11 marked radiopharmaceutical using a Ge68-Ga68 itinerant generator. Methodology: analysis of the visual aspect, pH and radiochemical purity of the marked radiopharmaceutical on each receiving of the Ge68-Ga68 generator. Results: all performed markings were clear in terms of visual appearance, pH was between 5.0 and 6.0 and radiochemical purity was 92% with value ≥ 96%. Conclusion: with proper quality controls it can be an option for application in the medical clinic, services centers unable to purchase a system due to importation process.


Subject(s)
Prostatic Neoplasms , Quality Control , Radiopharmaceuticals , Positron Emission Tomography Computed Tomography
6.
Chinese Journal of Experimental and Clinical Virology ; (6): 75-79, 2018.
Article in Chinese | WPRIM | ID: wpr-805914

ABSTRACT

Objective@#To study the intracellular location and characteristic of SFTSV NP protein in different phases using mini singlet oxygen generator (miniSOG) labeling technique.@*Methods@#MiniSOG is a recently-invented genetically-encoded tag for EM. MiniSOG-fused SFTSV NP (NPSOG) gene was cloned by PCR, and inserted into pcDNA3.0 plasmid to form pTPL-NPSOG, which was used to transfect 293 cells. The transfected cells of different phases were fixed in 2.5% glutaraldehyde in situ, stained with DAB through the photooxidation activity of miniSOG, and used to prepare ultrathin sections. Intracellular location and characteristic of SFTSV NP protein in different phases were studied by observing the sections under transmission electron microscope.@*Results@#After transfecting the plasmid with NPSOG to 293 cells, NP protein was expressed in cytoplasm and peri nucleus, and gradually aggregated, which connected with endoplasmic reticulum and Golgi apparatus to form larger volume and irregular inclusion bodies in cytoplasm. No obvious subcellular structure changes were found.@*Conclusions@#The SFTSV nucleoprotein can be expressed separately to form inclusion bodies without the assistance of other viral proteins. The formation of inclusion bodies requires the directional movement and aggregation of a certain number of NP proteins, which may involve the interaction of NP protein and host organelles during this period.

7.
Annals of Laboratory Medicine ; : 512-517, 2018.
Article in English | WPRIM | ID: wpr-718333

ABSTRACT

BACKGROUND: Complete blood count (CBC) results play an important role in peripheral blood smear (PBS) examinations. Many descriptions in PBS reports may simply be translated from CBC parameters. We developed a computer program that automatically generates a PBS draft report based on CBC parameters and age- and sex-matched reference ranges. METHODS: The Java programming language was used to develop a computer program that supports a graphical user interface. Four hematology analyzers from three different laboratories were tested: Sysmex XE-5000 (Sysmex, Kobe, Japan), Sysmex XN-9000 (Sysmex), DxH800 (Beckman Coulter, Brea, CA, USA), and ADVIA 2120i (Siemens Healthcare Diagnostics, Eschborn, Germany). Input data files containing 862 CBC results were generated from hematology analyzers, middlewares, or laboratory information systems. The draft reports were compared with the content of input data files. RESULTS: We developed a computer program that reads CBC results from a data file and automatically writes a draft PBS report. Age- and sex-matched reference ranges can be automatically applied. After examining PBS, users can modify the draft report based on microscopic findings. Recommendations such as suggestions for further evaluations are also provided based on morphological findings, and they can be modified by users. The program was compatible with all four hematology analyzers tested. CONCLUSIONS: Our program is expected to reduce the time required to manually incorporate CBC results into PBS reports. Systematic inclusion of CBC results could help improve the reliability and sensitivity of PBS examinations.


Subject(s)
Blood Cell Count , Clinical Laboratory Information Systems , Delivery of Health Care , Hematology , Indonesia , Information Storage and Retrieval , Programming Languages , Reference Values
8.
Biomedical Engineering Letters ; (4): 383-392, 2018.
Article in English | WPRIM | ID: wpr-717985

ABSTRACT

For prompt gamma ray imaging for biomedical applications and environmental radiation monitoring, we propose herein a multiple-scattering Compton camera (MSCC). MSCC consists of three or more semiconductor layers with good energy resolution, and has potential for simultaneous detection and differentiation of multiple radio-isotopes based on the measured energies, as well as three-dimensional (3D) imaging of the radio-isotope distribution. In this study, we developed an analytic simulator and a 3D image generator for a MSCC, including the physical models of the radiation source emission and detection processes that can be utilized for geometry and performance prediction prior to the construction of a real system. The analytic simulator for a MSCC records coincidence detections of successive interactions in multiple detector layers. In the successive interaction processes, the emission direction of the incident gamma ray, the scattering angle, and the changed traveling path after the Compton scattering interaction in each detector, were determined by a conical surface uniform random number generator (RNG), and by a Klein-Nishina RNG. The 3D image generator has two functions: the recovery of the initial source energy spectrum and the 3D spatial distribution of the source. We evaluated the analytic simulator and image generator with two different energetic point radiation sources (Cs-137 and Co-60) and with an MSCC comprising three detector layers. The recovered initial energies of the incident radiations were well differentiated from the generated MSCC events. Correspondingly, we could obtain a multi-tracer image that combined the two differentiated images. The developed analytic simulator in this study emulated the randomness of the detection process of a multiple-scattering Compton camera, including the inherent degradation factors of the detectors, such as the limited spatial and energy resolutions. The Doppler-broadening effect owing to the momentum distribution of electrons in Compton scattering was not considered in the detection process because most interested isotopes for biomedical and environmental applications have high energies that are less sensitive to Doppler broadening. The analytic simulator and image generator for MSCC can be utilized to determine the optimal geometrical parameters, such as the distances between detectors and detector size, thus affecting the imaging performance of the Compton camera prior to the development of a real system.


Subject(s)
Clothing , Gamma Rays , Isotopes , Radiation Monitoring , Semiconductors
9.
An. acad. bras. ciênc ; 89(3): 1343-1367, July-Sept. 2017. tab, graf
Article in English | LILACS | ID: biblio-886752

ABSTRACT

New generators are required to define wider distributions for modeling real data in survival analysis. To that end we introduce the four-parameter generalized beta-generated Lindley distribution. It has explicit expressions for the ordinary and incomplete moments, mean deviations, generating and quantile functions. We propose a maximum likelihood procedure to estimate the model parameters, which is assessed through a Monte Carlo simulation study. We also derive an additional estimation scheme by means of least square between percentiles. The usefulness of the proposed distribution to describe remission times of cancer patients is illustrated by means of an application to real data.

10.
ARS med. (Santiago, En línea) ; 42(3): 31-39, 2017.
Article in Spanish | LILACS | ID: biblio-1017246

ABSTRACT

La estimulación de la Médula Espinal (EME) es una técnica de neuromodulación que ha mostrado ser efectiva en el manejo de los trastornos motores propios de enfermedades tan devastadoras como la Enfermedad de Parkinson (EP) y las lesiones de la médula espinal. Considerando que ambas patologías cuentan con opciones terapéuticas limitadas, la EME se podría posicionar como una técnica prometedora. Los mecanismos por los cuales operaría la estimulación difieren en ambos casos, generando cambios en la circuitería espinal local en el caso de las lesiones medulares, y cambios supraespinales, en el caso de la EP. En esta revisión se busca analizar los efectos de la EME en ambas enfermedades, tanto en modelos animales como en pacientes, hacer una breve descripción de los mecanismos y aludir a los desafíos futuros propuestos para ambos casos. (AU)


Spinal cord stimulation (SCS) is a neurophysiological technique that has shown to be effective in modulating motor dysfunction associated with devastating diseases such as: Parkinson's disease (PD) and spinal cord injuries. Considering that both pathologies have limited treatment options, SCS could be considered as a potential useful technique. The mechanism by which stimulation operates differs in both cases, generating changes in local circuits in the case of spinal cord injuries and supraspinal changes in PD. This review aims to analyze the effects of EES on both diseases, focusing in the results observed in animal models and patients, give a brief description of the mechanisms behind and postulate the future challenges proposed for SCS in both pathologies.(AU)


Subject(s)
Humans , Male , Female , Spinal Cord Stimulation , Parkinson Disease , Spinal Cord Diseases , Transcutaneous Electric Nerve Stimulation
11.
International Neurourology Journal ; : 270-272, 2016.
Article in English | WPRIM | ID: wpr-124494

ABSTRACT

The objective of this study was to describe our experience using sacral neuromodulation to treat urinary urgency, frequency, urge incontinence, and chronic urinary retention in patients with cardiac pacemakers. With the increasingly widespread use of InterStim for bladder function restoration, we are seeing more complex patients with multiple comorbidities, including cardiac conditions. Herein, we report 3 cases of individuals with cardiac pacemakers who underwent InterStim implantation to treat urinary conditions. This study is a case series of 3 patients with cardiac pacemakers who underwent sacral neuromodulation to treat refractory voiding dysfunction. The initial patient screening for InterStim therapy involved percutaneous nerve evaluation (PNE), in which a temporary untined lead wire was placed through the S3 foramen. Patients who did not respond to PNE proceeded to a staged implant. All patients in this study had a greater than 50% improvement of their urinary symptoms during the initial trial and underwent placement of the InterStim implantable pulse generator (IPG). Postoperative programming was done under electrocardiogram monitoring by a cardiologist. No interference was observed between the Inter-Stim IPG and the cardiac pacemaker. In this group of patients, sacral neuromodulation in the presence of a cardiac pacemaker appears to have been safe.


Subject(s)
Humans , Comorbidity , Electrocardiography , Mass Screening , Urinary Bladder , Urinary Incontinence, Urge , Urinary Retention
12.
Journal of Modern Laboratory Medicine ; (4): 115-117, 2015.
Article in Chinese | WPRIM | ID: wpr-482625

ABSTRACT

Objective To establish the method for determination of bromate in drinking water by eluent generator suppressed conductivity ion chromatography.Methods Used application of American Dionex ICS-2100 ion chromatograph and EGC-III eluent automatic generator for ion chromatography gradient elution method to do determination of bromate in drinking water [IonPac AS19 (4×250 mm)].Eluent generator produced KOH online,gradient elution,Flow rate:1.0 ml/min.Results The method was linear in the range of Y =-0.000 609 7+0.000 873 1X,r =0.999 9,high precision (CV% < 1.5).The samples average of recovery was 99.5%~100.8%.The lowest detection limit was 0.50 μg/L.Conclusion Ion chromatog-raphy gradient elution method for the determination of bromate in drinking water was simple,rapid,and sensitive.It can be suitable for determination of bromate in drinking water.

13.
Innovation ; : 20-23, 2015.
Article in Mongolian | WPRIM | ID: wpr-975514

ABSTRACT

Effects of industrial noise have been recognized by humanity since mid 19th century and works to study and prevent industrial noises had begun globally. Strong industrial noises damage human internal ear and hair cell of cort-organ rapidly and gradually, which causes deafness; and thousands of people are suffering from health problems. Many noisy industries, where thousands of people work, were built in our country by 1960’s anddeafness has increased due to exposure of industrial noise. Scientific studies to measure the level of industrial noise, to determine the hearing level of people who are working in it, to study the relationship between noise and hearing loss still haven’t been conducted completely. Aim: To measure distribution zone of industrial noise generator which generates noise with more than 85, to study hearing threshold of the people who are constantly affected by it, to prevent noise hearing loss.The plants of “Erdenet Industry” JSC, TPP-4 SOC, “Darkhan TU” SOC, TPP-3 SOC have been chosenwithin scope of the research. Noise level of 42 instruments of these plants which produces noise over85 “Noise distribution zone” where noise level decreases to 85, Chose 480 employees who have beenaffected by it for more than 5 years.Using modern audiometer at 250, 500, 1000, 2000, 4000, 8000 Hz to measure for each bone and air conduction in noise-proof rooms Average hearing thresholds are calculated at dense, medium, pitched noise levelEarplug and headphone were used at shop and assembly line with noise over 85 дБ for more than 24 hours by employees, their satisfaction was studied and it was watched that if they were using the protective equipment regularly.Hearing threshold of employees who constantly work at noisy environment found to be 28.5±3.8 dB atdense noise 31.8±4.4±0.3 at medium noise, 38.2±5.7 dB at pitched noise level for “Erdenet Industry” JSC, 30.9±3.1±0.3 дБ at dense noise, 34.6±3.5 dB at medium noise, 39.5±4.3 dB at pitched noise level for TPP-4 SOC, 31.9±3.6 dB at dense noise, 34.9±3.8 dB at medium noise, 40.9±4.1 dB at pitched noise level for “Darkhan TU” SOC, 28.9±2.6 dB at dense noise, 32.4±2.8 dB at medium noise, 36.4±4.4 dB at pitched noise level for TPP-3 SOC. 95.6% of employees of “Erdenet Industry” JSC, 95.7% of employees of TPP-4 SOC, 96.5 % of employees of “Darkhan TU” SOC, 95.8 % of employees of TPP-3 SOC were satisfied when noise protection tools Ear classic and Bilsom were used at environment with noise level over 85 dB. Average hearing threshold of employees who have worked for more than 5 years in weak industrial noise level (85 – 92.5 dB) found to be 28.4±3.0 dB at dense noise, 32.3±3.2 dB at medium noise, 37.1±4.5 dB at pitched noise level, for medium noise level environment 30.2±3.4±0.3 dB at dense noise, 33.5±4.0 dB at medium noise, 39.2±4.4 dB at pitched noise level, for strong noise environment 34.1±3.6 dB at dense noise, 34.5±3.8±0.4 at medium noise, 34.8±4.5 dB at pitched noise level, or it was reduced from healthy hearing threshold with true possibility when p=0.05.95.6% of employees of “Erdenet Industry” JSC, 95.7% of employees of TPP-4 SOC, 96.5 % of employees of “Darkhan TU” SOC, 95.8 % of employees of TPP-3 SOC were satisfied when noise protection tools Ear classic and Bilsom were used at environment with noise level over 85 dB, which makes these tools reliable protectors from hearing loss due to noise.

14.
Korean Journal of Veterinary Research ; : 151-157, 2014.
Article in Korean | WPRIM | ID: wpr-129077

ABSTRACT

A nationwide survey on radiation safety management in Korean animal hospitals was conducted. By 2013, 53 radiation generators were registered as veterinary medical devices (41 X-ray generators and 12 computed tomography scanners). Additionally there were six approved laboratories for radiation equipment and protection facility, and five approved laboratories for radiation exposure of employees, respectively. By March 2013, 2,030 out of 3,829 animal hospitals operated radiation-generating devices. Among these devices, 389 (19.2%) out of 2,030 were not labeled with the model name and 746 (36.7%) were not labeled with production dates. Thus, most veterinary X-ray generators were outdated (42.6%) and needed replacements. When periodic inspections of 2,018 animal hospitals were performed after revision of the Veterinarians Act in 2011, the hospitals were found to be equipped with appropriate radiation generators and protection facilities. Among 2,545 employees exposed to radiation at the hospitals, 93.9% were veterinarians, 4.3% were animal nurse technicians, and 18% held other positions. Among 169 employees supervised by administrators, none of those had a weekly maximum operating load that exceeded 10 mA.min. This study suggests that the radiation safety management system of animal hospitals was general good.


Subject(s)
Animals , Humans , Administrative Personnel , Hospitals, Animal , Korea , Safety Management , Veterinarians
15.
Korean Journal of Veterinary Research ; : 151-157, 2014.
Article in Korean | WPRIM | ID: wpr-129063

ABSTRACT

A nationwide survey on radiation safety management in Korean animal hospitals was conducted. By 2013, 53 radiation generators were registered as veterinary medical devices (41 X-ray generators and 12 computed tomography scanners). Additionally there were six approved laboratories for radiation equipment and protection facility, and five approved laboratories for radiation exposure of employees, respectively. By March 2013, 2,030 out of 3,829 animal hospitals operated radiation-generating devices. Among these devices, 389 (19.2%) out of 2,030 were not labeled with the model name and 746 (36.7%) were not labeled with production dates. Thus, most veterinary X-ray generators were outdated (42.6%) and needed replacements. When periodic inspections of 2,018 animal hospitals were performed after revision of the Veterinarians Act in 2011, the hospitals were found to be equipped with appropriate radiation generators and protection facilities. Among 2,545 employees exposed to radiation at the hospitals, 93.9% were veterinarians, 4.3% were animal nurse technicians, and 18% held other positions. Among 169 employees supervised by administrators, none of those had a weekly maximum operating load that exceeded 10 mA.min. This study suggests that the radiation safety management system of animal hospitals was general good.


Subject(s)
Animals , Humans , Administrative Personnel , Hospitals, Animal , Korea , Safety Management , Veterinarians
16.
Military Medical Sciences ; (12): 270-272, 2014.
Article in Chinese | WPRIM | ID: wpr-447509

ABSTRACT

This paper introduces the basic function , composition and framework of the Patient Condition ( PC) codes and the Patient Workload Generator ( PATGEN ) that are used for classification of the wounded and simulation of the patient generation for the U.S.Armed Forces.In addition, chi-square statistics and comparative methods were used for the , analysis of the difference between the simulation data and the real data in Iraq wary .The result of simulation accuracy was tested.Finally, ways to carry out medical service simulation in China were discussed .

17.
China Medical Equipment ; (12): 58-60, 2014.
Article in Chinese | WPRIM | ID: wpr-444505

ABSTRACT

Objective:Mobile X-ray radiographic Units to appear in the clinical application of high voltage circuit judge special case of failure, the analysis in order to provide effective and reliable service basis. Methods: Preliminary judgment based fault location fault code, using stepwise exclusion analyze, judge, and determine the cause of the failure lies. Results:The high-voltage inverter element models of mobile DR, the driver circuit, the output voltage discharge waveform judgment and other issues have a better understanding, to facilitate the exclusion of equipment failure. Conclusion:Special case of X-ray radiographic Units failure high voltage circuit analysis and troubleshooting, especially for the inverter circuit analysis, X-ray radiographic appear to take timely and appropriate repair method when high pressure overload.

18.
Rev. ing. bioméd ; 6(11): 46-52, ene.-jun. 2012. graf
Article in Spanish | LILACS | ID: lil-769122

ABSTRACT

El electrocardiograma abdominal es una técnica de monitoreo promisoria para la vigilancia en el periodo prenatal, ya que presenta facilidad de adquisición y permite la supervisión materna y fetal simultáneamente. La separación de estas señales es complicada y no existe una forma estandarizada de evaluar la efectividad de algoritmos reportados en la literatura. Basados en un modelo de dipolo propagado en el abdomen materno tridimensional, el presente trabajo propone la implementación de un sistema de generación de señales de ECG abdominal, con características controlables de simulación de condiciones reales: interferencias, variabilidad de periodos cardiacos, número de canales, ubicación de electrodos y posición fetal. Con el sistema desarrollado se generaron 50 señales sintéticas de prueba que mostraron una correlación de 0,99 con respecto a valores esperados en la relación señal-interferencia, sin diferencias significativas en la regresión (p>0.05); mientras que el coeficiente de correlación para la relación señal a ruido fue de 0.87 con diferencias significativas en la regresión por debajo de los -20 dB (p<0.05). En conclusión, el sistema propuesto proporciona señales de ECG abdominal con condiciones similares a las de señales reales, lo cual facilita la adecuada evaluación de algoritmos de separación de ECG materno y fetal a partir del ECG abdominal.


Abdominal ECG is one of the most promising monitoring techniques for fetal surveillance in the antenatal period, as it presents easy availability and allows the maternal and fetal monitoring simultaneously. However, separation of these signals is complicated and there is no standardized way to evaluate the effectiveness of separation algorithms reported in the literature. Based on the dipole model spread through the three-dimensional maternal abdomen, this paper proposes the implementation of a system for the generation of abdominal ECG signals with controllable characteristics simulating real conditions by interference, heart period variability, number of channels , electrodes location and fetal position. Using the developed system, 50 synthetic test signals were generated and compared with desired values. Results showed a correlation of 0.99 with respect to expected values in the signal interference ratio, with no significant differences in the regression (p>0.05); while the correlation coefficient was 0.87 for the signal to noise ratio, with significant differences below -20 dB (p<0.05) in the regression. In conclusion, the proposed system provides abdominal ECG signals showing similar conditions to those of real signals, and comprises a tool that ensures proper evaluation of separation algorithms of maternal and fetal ECG from abdominal ECG.

19.
Rev. chil. neuro-psiquiatr ; 48(1): 44-48, mar. 2010. ilus
Article in Spanish | LILACS | ID: lil-577344

ABSTRACT

The simultaneous and involuntary displacement of the opposite limb during a volitional movement is called mirror movements. They mimic the gesture, partly or wholly. They can be congenital, familiar or installed in various CNS pathologies. We present a 64 years old woman with familiar history of mirror movements that affect their hands, since childhood. At admission presented confused with left hemiplegia and homolateral sensory involvement. The brain CT defined a right ischemic stroke affecting the posterior limb of the internal capsule, lenticular nucleus, sub insular region and par ventricular white matter. The paretic left hand, unable to perform voluntary movements, presented mirror movements during volitional movements of the contra lateral hand. Neurophysiologic studies have suggested that mirror movements are due the activation of the direct corticospinal pathway or simultaneous discharge of both motor cortexes due inhibitory pathways failures. Cortical origin seems unlikely for the movements in this patient, due to the injury of the internal capsule. Our case could be interpreted by the simultaneously brain innervations on both anterior horns, together with a congenital deregulation of the Central Pattern Generator Networks.


Se denomina movimiento en espejo (ME) el desplazamiento involuntario, imitativo y simultáneo de la extremidad opuesta al de un movimiento volitivo. Los ME pueden tener un origen congénito y familiar o generarse por patologías diversas del sistema nervioso central. Se presenta una mujer de 64 años con el antecedente de ME desde la infancia de carácter familiar. Ingresa en estado confusional y presentando una hemiplejía y hemihipoestesia faciobraquicrural izquierda. La tomografía cerebral mostraba compromiso del brazo posterior de la cápsula interna, núcleo lenticular, región subinsular y de la sustancia blanca paraventricular. La mano izquierda pléjica que era incapaz de realizar movimientos voluntarios, se movía en espejo al mover la mano derecha. Esta curiosa manifestación hace necesario una más ajustada interpretación neurofisiológica de los movimientos en espejo. Se ha postulado una activación de la vía corticoespinal directa, o la descarga simultánea de ambas cortezas motoras por fallas en la natural inhibición transcortical. En este caso parece improbable un origen cortical contralateral de los movimientos, debido a la lesión de la cápsula. Tal vez podrían comprenderse los ME de esta paciente, si se demostrara una doble inervación de ambas astas anteriores, asociada a una falla en la inhibición normal por desregulación congénita de los Circuitos Generadores Centrales.


Subject(s)
Humans , Female , Middle Aged , Hemiplegia/diagnosis , Cerebral Infarction/complications , Movement Disorders/congenital , Movement Disorders/physiopathology , Stroke/complications , Functional Laterality , Hand/physiopathology , Reflex , Synkinesis , Central Nervous System/physiopathology
20.
Nuclear Medicine and Molecular Imaging ; : 330-336, 2009.
Article in Korean | WPRIM | ID: wpr-33865

ABSTRACT

PURPOSE: We established radiolabeling conditions of NOTA and DOTA with a generator-produced PET radionuclide 68Ga and studied in vitro characteristics such as stability, serum protein binding, octanol/water distribution, and interference with other metal ions. MATERIALS AND METHODS: Various concentrations of NOTA.3HCl and DOTA.4HCl were labeled with 1 mL 68GaCl3 (0.18~5.75 mCi in 0.1 M HCl) in various pH. NOTA.3HCl (0.373 mM) was labeled with 68GaCl3 (0.183~0.232 mCi/0.1 M HCl 1.0 mL) in the presense of CuCl2, FeCl2, InCl3, FeCl3, GaCl3, MgCl2 or CaCl2 (0~6.07 mM) at room temperature. The labeling efficiencies of 68Ga-NOTA and 68Ga-DOTA were checked by ITLC-SG using acetone or saline as mobile phase. Stabilities, protein bindings, and octanol distribution coefficients of the labeled compounds also were investigated. RESULTS: 68Ga-NOTA and 68Ga-DOTA were labeled optimally at pH 6.5 and pH 3.5, respectively, and the chelates were stable for 4 hr either in the reaction mixture at room temperature or in the human serum at 37 degreesC. NOTA was labeled at room temperature while DOTA required heating for labeling. 68Ga-NOTA labeling efficiency was reduced by CuCl2, FeCl2, InCl2, FeCl3 or GaCl3, however, was not influenced by MgCl2 or CaCl2. The protein binding was low (2.04~3.32%). Log P value of 68Ga-NOTA was -3.07 indicating high hydrophilicity. CONCLUSION: We found that NOTA is a better bifunctional chelating agent than DOTA for 68Ga labeling. Although, 68Ga-NOTA labeling is interfered by various metal ions, it shows high stability and low serum protein binding.


Subject(s)
Humans , Acetone , Copper , Electrons , Enzyme Multiplied Immunoassay Technique , Gallium , Heating , Heterocyclic Compounds , Hot Temperature , Hydrogen-Ion Concentration , Hydrophobic and Hydrophilic Interactions , Ions , Magnesium Chloride , Protein Binding , Protein Stability
SELECTION OF CITATIONS
SEARCH DETAIL