Research and Design of Automatic Test System for Ventilator Performance / 中国医疗器械杂志

Ventilator is an important medical instrument which can replace the function of autonomous ventilation artificially. Its safety and reliability are related to the health and even life safety of patients. With the publishing of the new national standard and international standard for ventilators, higher requirements are put forward for the detection and evaluation. This study mainly introduces an automatic test system for ventilator performance. The test system is based on PF-300 air-flow analyzer of Imtmedical and standard simulation lung. The automatic switch module of simulation lung is developed, and the automatic test system of ventilator is designed using the software development platform based on Python. It can not only automatically test all ventilation control parameters and monitoring parameters of the ventilator, but also realize automatic data recording, form reports and data analysis, and improve the efficiency and quality of inspection, detection and quality control.

Spatial-resolved metabolomics reveals tissue-specific metabolic reprogramming in diabetic nephropathy by using mass spectrometry imaging

Detailed knowledge on tissue-specific metabolic reprogramming in diabetic nephropathy (DN) is vital for more accurate understanding the molecular pathological signature and developing novel therapeutic strategies. In the present study, a spatial-resolved metabolomics approach based on air flow-assisted desorption electrospray ionization (AFADESI) and matrix-assisted laser desorption ionization (MALDI) integrated mass spectrometry imaging (MSI) was proposed to investigate tissue-specific metabolic alterations in the kidneys of high-fat diet-fed and streptozotocin (STZ)-treated DN rats and the therapeutic effect of astragaloside IV, a potential anti-diabetic drug, against DN. As a result, a wide range of functional metabolites including sugars, amino acids, nucleotides and their derivatives, fatty acids, phospholipids, sphingolipids, glycerides, carnitine and its derivatives, vitamins, peptides, and metal ions associated with DN were identified and their unique distribution patterns in the rat kidney were visualized with high chemical specificity and high spatial resolution. These region-specific metabolic disturbances were ameliorated by repeated oral administration of astragaloside IV (100 mg/kg) for 12 weeks. This study provided more comprehensive and detailed information about the tissue-specific metabolic reprogramming and molecular pathological signature in the kidney of diabetic rats. These findings highlighted the promising potential of AFADESI and MALDI integrated MSI based metabolomics approach for application in metabolic kidney diseases.

metabolomics in nephrotoxicity of aristolochic acids based on air flow-assisted desorption electrospray ionization mass spectrometry imaging

Understanding of the nephrotoxicity induced by drug candidates is vital to drug discovery and development. Herein, an metabolomics method based on air flow-assisted desorption electrospray ionization mass spectrometry imaging (AFADESI-MSI) was established for direct analysis of metabolites in renal tissue sections. This method was subsequently applied to investigate spatially resolved metabolic profile changes in rat kidney after the administration of aristolochic acid I, a known nephrotoxic drug, aimed to discover metabolites associated with nephrotoxicity. As a result, 38 metabolites related to the arginine-creatinine metabolic pathway, the urea cycle, the serine synthesis pathway, metabolism of lipids, choline, histamine, lysine, and adenosine triphosphate were significantly changed in the group treated with aristolochic acid I. These metabolites exhibited a unique distribution in rat kidney and a good spatial match with histopathological renal lesions. This study provides new insights into the mechanisms underlying aristolochic acids nephrotoxicity and demonstrates that AFADESI-MSI-based metabolomics is a promising technique for investigation of the molecular mechanism of drug toxicity.

Novel approach for real-time monitoring of carrier-based DPIs delivery process pulmonary route based on modular modified Sympatec HELOS

An explicit illustration of pulmonary delivery processes (PDPs) was a prerequisite for the formulation design and optimization of carrier-based DPIs. However, the current evaluation approaches for DPIs could not provide precise investigation of each PDP separately, or the approaches merely used a simplified and idealized model. In the present study, a novel modular modified Sympatec HELOS (MMSH) was developed to fully investigate the mechanism of each PDP separately in real-time. An inhaler device, artificial throat and pre-separator were separately integrated with a Sympatec HELOS. The dispersion and fluidization, transportation, detachment and deposition processes of pulmonary delivery for model DPIs were explored under different flow rates. Moreover, time-sliced measurements were used to monitor the PDPs in real-time. The Next Generation Impactor (NGI) was applied to determine the aerosolization performance of the model DPIs. The release profiles of the drug particles, drug aggregations and carriers were obtained by MMSH in real-time. Each PDP of the DPIs was analyzed in detail. Moreover, a positive correlation was established between the total release amount of drug particles and the fine particle fraction (FPF) values ( = 0.9898). The innovative MMSH was successfully developed and was capable of illustrating the PDPs and the mechanism of carrier-based DPIs, providing a theoretical basis for the design and optimization of carrier-based DPIs.

Study on Tissue Distribution of A Variety of Endogenous Metabolites by Air Flow Assisted Ionization-Ultra High Resolution Mass Spectrometry Imaging / 分析化学

As a promising new molecular imaging technique,mass spectrometry imaging(MSI) has attracted more and more attention in the field of biomedicine. A method of air flow assisted ionization-ultra high resolution mass spectrometry-based mass spectrometric imaging (AFAI-MSI) was developed to profile endogenous metabolites in rat kidney tissue in this study. Rat kidneys were collected and cut into frozen tissue sections,and then were analyzed on an AFAI-MSI system in positive ion mode using acetonitrile-isopmpyl alcohol-water (4:4:2,V/V,5 μL/min) as spray solvent,N2as spray gas(0.6 MPa) and air as assisting gas (45 L/min). The mass range and resolution were set to be 70-1000 Da and 70000, respectively. As a result,a total of 38 metabolites, including organic amines, sugars, vitamins, peptides, neurotransmitters, organic acids,phospholipids,sphingolipids,glyceride,and cholesterol esters, were identified and imaged to characterize their tissue-specific distribution in kidney tissues, and some metabolites, such as choline, acetylcoline,betaine,phoshocholine,and glycerophosphocholine were found to have distinct distribution along the cortex-medulla axis,which may be involved in the formation of osmotic pressure gradient in the kidney. The proposed ultra high resolution mass spectrometry based AFAI-MSI method could work without sample pretreatment, showed high sensitivity and wide metabolite coverage, and was expected to provide a new analytical approach for the research of in situ characterization and metabolic regulation mechanism of endogenous metabolites in kidney.

Three-dimensional DEM-CFD analysis of air-flow-induced detachment of API particles from carrier particles in dry powder inhalers

Air flow and particle-particle/wall impacts are considered as two primary dispersion mechanisms for dry powder inhalers (DPIs). Hence, an understanding of these mechanisms is critical for the development of DPIs. In this study, a coupled DEM-CFD (discrete element method-computational fluid dynamics) is employed to investigate the influence of air flow on the dispersion performance of the carrier-based DPI formulations. A carrier-based agglomerate is initially formed and then dispersed in a uniformed air flow. It is found that air flow can drag API particles away from the carrier and those in the downstream air flow regions are prone to be dispersed. Furthermore, the influence of the air velocity and work of adhesion are also examined. It is shown that the dispersion number (i.e., the number of API particles detached from the carrier) increases with increasing air velocity, and decreases with increasing the work of adhesion, indicating that the DPI performance is controlled by the balance of the removal and adhesive forces. It is also shown that the cumulative Weibull distribution function can be used to describe the DPI performance, which is governed by the ratio of the fluid drag force to the pull-off force.

A Comparison of the Physical Activity of Hematopoietic Stem Cell Transplantation Patients and Healthy People

PURPOSE: The study aimed to compare the physical activity of hematopoietic stem cell transplantation (HSCT) patients with healthy people (HP). METHODS: The research design of this study was cross sectional and, descriptive study. It was conducted from January 26th to May 22nd, 2013. We matched HSCT patients to HP based on age and gender, and measured physical activity using a pedometer. Patient's clinical information were gathered by the medical record reviews. RESULTS: The number of steps was significantly less in HSCT patients (HSCT: 214 (7~3,373) vs HP: 7,921 (3,180~17,539), p<.001). Physical activity time was significantly less in HSCT patients (HSCT: 840 (680~1,320)min vs HP: 990 (540~1,090)min, p<.001). Step count showed a significant relationship with platelet count (r=.40, p=.004). CONCLUSION: HSCT patients perform very low intensity of physical activities. The study shows the necessity to apply programs to promote physical activities in isolation rooms for patients undergoing HSCT.

Application of Factor Analysis in Imaging Mass Spectrometric Data Analysis / 分析化学

The factor analysis method applied in imaging mass spectrometry data analysis was studied. The imaging mass spectrometric data were obtained by air flow-assisted ionization imaging mass spectrometry method. The sample contained some symbols which were drawn on slides using three different inks ( red, blue, black) . The imaging data analyzed by factor analysis method were divided into the background, black, blue and red factor. The results showed that the scores of m/z=443. 2, 478. 4, 322. 2(344. 2) in red, blue, black factor respectively were much larger than others. Therefore, they were markers of three inks. The results accorded with actual condition well and proved that the application of factor analysis in imaging mass spectrometric data analysis was feasible. The data analysis results of factor analysis and principal component analysis were compared. The results showed that the target sample markers could be extracted by factor analysis simply and quantitatively. It was of great potential in biomarker extraction, diseases diagnose and pharmacological analysis.

Calidad microbiológica del aire de una unidad de preparados farmacéuticos estériles / Bacteriological quality of air in a ward for sterile pharmaceutical preparations

Introducción: La elaboración de preparados farmacéuticos estériles requiere áreas limpias que deben cumplir estándares internacionales para minimizar la contaminación microbiana. Objetivo: Evaluar la calidad bacteriológica del aire de la Unidad de Preparados Farmacéuticos Estériles del Servicio de Farmacia del Hospital Clínico de la Universidad de Chile y establecer niveles de alerta y acción. Material y Métodos: Se monitorearon ocho puntos representativos de la unidad, diariamente entre enero y febrero de 2005 y bisemanal-mente de junio a febrero de 2006. Se estudiaron 839 muestras de aire, recolectadas mediante el método de impacto en placa (equipo MAS-100). Resultados: De las muestras estudiadas, 474 (56,5 por ciento) fueron positivas; de éstas, sólo 17 (3,5 por ciento) estuvieron fuera del rango permitido, porcentaje que representa el 2 por ciento del total. Las muestras de los sitios 1 y 2 (flujo laminar grande y pequeño), que corresponden al área de preparación de preparados estériles fueron negativas. Los sitios 3 (mesón) y 4 (transfer) presentaron ocasionalmente valores superiores a los límites. Los microorganismos más frecuentes fueron Staphylococcus coagulasa negativa, Micrococcus spp y Corynebacterium spp, agentes de la microbiota de la piel y, menor porcentaje, Bacillus spp, agente de la microbiota ambiental. Conclusiones: Desde el punto de vista microbiológico, la calidad del aire de la zona de preparaciones estériles descrita presenta niveles ajustados a estándares internacionales. El establecer niveles de alerta y acción institucionales y la identificación de los microorganismos obtenidos en las áreas más sensibles de la unidad permite cuantificar la carga microbiana y conocer sus componentes para determinar las intervenciones a realizar cuando ellas estén indicadas.

Background: An extremely clean area is required for preparation of sterile pharmaceutical compounds, in compliance with international standards, to minimize the probability of microbial contamination. Aim: To evaluate the bacteriological quality of the air in the Sterile Pharmaceutical Preparation Unit of the University of Chile's Clinical Hospital and to set up alerts and action levels of bacterial growth. Methods: We studied eight representative sites of our Unit on a daily basis from January to February 2005 and twice a week from June 2005 to February 2006. We collected 839 samples of air by impact in the Petri dish. Results: 474 (56.5 percent) samples were positive; 17 (3.5 percent) of them had an inappropriate bacterial growth (2 percent of total samples). The samples from sites 1 and 2 (big and small biosafety cabinets) were negative. The countertop and transfer area occasionally exceeded the bacterial growth limits. The most frequently isolated bacteria were coagulase-negative staphylococci, Micrococcus spp and Corynebacterium spp, from skin microbiota, and Bacillus spp, an environmental bacteria. Conclusions: From a microbiological perspective, the air quality in our sterile preparation unit complied with international standards. Setting institutional alerts and action levels and appropriately identifying bacteria in sensitive areas permits quantification of the microbial load and application of preventive measures.

Air Quality Between Two Types of Operating-rooms:A Comparative Analysis / 中华医院感染学杂志

OBJECTIVE To learn about the factors affecting the quality of the air in operating-rooms and discuss the methods of improving their air quality.METHODS The dynamic and static air bacteriology between laminar air flow operating-room and normal operating-room of a fertiary care level hospital of grade Ⅰ in Changchun were observed.RESULTS The passing rate of samples for air static bacteriology between two types of operating rooms at the begining of selective operations(T0) was without difference.At the begining of emergency operations,there was a disparity.The total number of bacteria in normal operating-room increased with the operating-time,but in the laminar flow operating-room,the total number of bacteria increased in fluctuations during the(T2) time(60 ming since operation begain),and descended dramatically during the(T3) time(90 min since operation).CONCLUSIONS The emergency and operation-time are the main factors affecting the air quality in operating-room and the cleaning air-condition could improve the air quality.

Interface homem-máquina para controle de processos de resfriamento com ar forçado visando à economia de energia / Man-machine interface for the control of cooling processes with forced-air aimed at energy savings

Apresenta-se o desenvolvimento de um equipamento microprocessado, com saída de corrente, para controle da velocidade de rotação do motor do ventilador de sistemas de ar forçado, usando inversor de freqüência. Através de programação (software IHM.EXE), o usuário pode definir a massa a ser resfriada em quilogramas de produto. O equipamento calcula, através de um polinômio previamente estabelecido e programável, a freqüência de operação do inversor, que corresponde a uma vazão de ar específica, dentro dos limites estabelecidos no projeto. O equipamento foi instalado num sistema de resfriamento com ar forçado, estimando-se, pelo cálculo da variação da potência útil mecânica, uma economia de energia da ordem de 82 por cento, com uma rotação equivalente a 56 por cento da nominal do ventilador, proporcionando, desta forma, uma economia significativa no custo de operação do sistema.

The development of micro processed equipment is presented, with current exit for control of the speed of rotation of the fan motor of the system of forced air, using investing of the frequency. Through programming (software IHM.EXE), the user can define the mass to be cooled, in kilograms of the product. The equipment calculates through a programmable polynomial previously defined, the frequency of operation of the investor which corresponds to air specific flux, within the limits of the project. The equipment was installed in a forced-air cooling system, being considered by the calculation in useful mechanical power, the energy savings is estimated at around 82 percent with a rotation equivalent to 56 percent of the fan nominal, thus providing significant savings in system operating costs.

Styrene biofiltration in a trickle-bed reactor

The biological treatment of styrene waste gas in a trickle-bed filter (TBF) was investigated. The bioreactor consisted of a two-part glass cylinder (ID 150 mm) filled with 25 mm polypropylene Pall rings serving as packing material. The bed height was 1m. Although the laboratory temperature was maintained at 22 ºC, the water temperature in the trickle-bed filter was slightly lower (about 18 ºC).The main aim of our study was to observe the effect of empty-bed residence time (EBRT) on bioreactor performance at a constant pollutant concentration over an extended time period. The bioreactor was inoculated with a mixed microbial consortium isolated from a styrene-degrading biofilter that had been running for the previous two years. After three weeks of acclimation period, the bioreactor was loaded with styrene (100 mg.m-3). EBRT was in the range of 53 s to 13 s. A maximum elimination capacity (EC) of 11.3 gC.m-3.h-1 was reached at an organic loading (OL) rate of 18.6 gC.m-3.h-1.

Start-up and performance characteristics of a trickle bed reactor degrading toluene

The objective of this work was to evaluate toluene degradation in a trickle bed reactor when the loading was carried out by changing the air flow rate. The biofiltration system was inoculated with a mixed microbial population, adapted to degradation of hydrophobic compounds. Polypropylene high flow rings were used as a packing material. The system was operated for a period of 50 days at empty bed residence times ranging from 106s to 13s and with a constant inlet concentration of toluene of 100 mg.m-3. The reactor showed high removal efficiency at higher contact times and increasing elimination capacity with higher air-flow rates. The highest EC value reached was 9.8 gC.m-3.h-1 at EBRT = 13s. During the experiment, the consumption of NaOH solution was also measured. No significant variation of this value was found and an average value of 3.84 mmol of NaOH per gram of consumed carbon was recorded.

Implementary Effect of Air Purification and Environmental Management in Laminar Air-flow Operating Room / 中华医院感染学杂志

OBJECTIVE To explore the nursing supervision experience in laminar air-flow operating room(OR) and to provide a very clean and safe operating environment for the surgical patients,in order to prevent the operation infection and raise operation quality.METHODS To take the measures of aseptic,clean,purificatory management,and compare the ratio of infection of incisional wound on aseptic operation and the air bacteria detection results with the general operating room simultaneously.RESULTS The ratio of infection of incisional wound on aseptic operation was 0.05% in the laminar air-flow OR(group A) and 0.15% in the general operating room(group B),P

Significance of Aseptic Room Reverse Isolation in Febrile Neutropenic Cancer Patients / 대한소아혈액종양학회지

PURPOSE: The aim of this study is to find out the role of HEPA filter equipped lamina air flow room reverse isolation for the treatment of anticancer drug induced febrile neutropenic patients. METHODS: Antibiotics and antifungal agents were promptly administered to twenty six patients with febrile neutropenic following chemotherapy from January 2003 to July 2005 at the Department of Pediatrics, Kyungpook National University Hospital, Daegu, Korea. And if possible, they were treated in the aseptic room. RESULTS: Nineteen patients recovered and seven patients died of infectious causes among twenty six patients. Fourteen patients had microbiologically defined infection, seven patients had clinically defined infection, and five patients had unexplained fever. The causes of infection were sepsis, pneumonia and urinary tract infection. The etiologic pathogens were Gram negative bacilli, 6 (42.9%) ; Gram positive cocci, 3 (21.4%) ; and fungus, 5 (35.7%). The dead group showed lower leukocyte count and higher CRP than the survived group. All dead patients showed disseminated intravascular coagulation syndrome (DIC). Nine of the ten patients (90%) who were treated in the aseptic room survived and ten of the sixteen patients (62.5%) in the general ward survived. CONCLUSION: The infection-related mortality of febrile neutropenic patients following chemotherapy is influenced by the early and adequate use of antimicrobial agents, DIC, neutrophil count and CRP. The isolation in the aseptic room increased the survival rate, but it was not statistically significant.

Estudio del flujo de aire y la resistencia nasal en niños con edades comprendidas entre los seis y los doce años / Air Flow study and nassal resistance among children aged 6 to 12 years old

Por la incertidumbre existente con respecto a la posible relación entre los desórdenes respiratorios y las alteraciones del crecimiento y desarrollo del macizo craneofacial, con esta investigación se pretendió hacer un aporte al conocimiento científico mediante la obtención de datos claves acerca de la elaboración, calibración y validación de instrumentos confiables para la medición del flujo de aire, las caídas asociadas a la presión del aire inspirado y/o espirado y la resistencia nasal, en aras de poder cuantificar los valores de normalidad de la función respiratoria. Para tal efecto se diseñaron, construyeron, calibraron y se utilizaron experimentalmente instrumentos de medición de la función respiratoria. Como resultado de lo anterior, se obtuvieron curvas de calibración, tanto para el flujo de aire como para la diferencia de presión, que presentaron coeficientes de correlación (r) de 0.9997 y 0.9992, respectivamente. Mediante el uso de un espirómetro y un neumotacógrafo junto con transductores de presión conectados a un polígrafo, empleando una muestra por conveniencia compuesta por cuarenta y cuatro sujetos infantiles, con edades que oscilaron entre los seis y los doce años, se realizó un estudio piloto. En experimentos separados sobre los mismos sujetos y el uso dispositivos externos independientes, con el objeto de establecer la partición oral/nasal en la espiración espontánea de los sujetos en reposo se colectaron simultáneamente los gases espirados por vía nasal y oral durante un lapso de ocho minutos. Se registraron curvas de flujo de aire por vía nasal y de diferencias de presión orofaringe-máscara en niños sentados y en reposo. obre los trazados se calcularon el flujo medio de aire durante la inspiración y la diferencia media de presión orofaringe- máscara durante la misma fase, valores con los cuales se calculó la resistencia inspiratoria media de la vía nasal. Los valores de la resistencia nasal obtenida cayeron dentro del rango normal.

The unknown relationship among breathing disorders and development growing of skull and facial bones were the focal point of these research as a form to find key facts trough scientific approach regarding construction, calibrating and testing suitable instruments to measure breathing air flow and pressure air drops associated to inhalation and exhalation, as well as nasal resistance in order to quantify breathing normal values. To obtain these objectives, measure respiratory instruments were designed, build and tested. As a test product, correlated data for airflow and pressure drops calibrated curves at 0.9997 and 0.9992 values were obtained. By use of an expirometer and a pneumotachography machines along with pressure transducers connected to a polygraph, a pilot study was carry out on a by convenience sample of forty four child subjects whose ages raging between six to twelve years old. Using the same sample in separate experiments with external devices, exhalated air was collected by nasal and oral way during eight minutes; in order to achieve oral and nasal partition of subjects exhalation air at rest. Air flow and pressure drops by nasal way in children at rest were registered. Base on the medium records of air flow during inhalation and medium records of pressure drops calculated during the same stage, values which were used to calculate the medium inspiratory resistance of the nasal way. The nasal resistance values calculated within an average of 5.4 cm H2O/l/s, a standard deviation of 1.96 cm H2O/l/ were considerate into the normal range. Results of this pilot study showed low correlation in most of the respiratory connections measured on the studied subjects; future studies must use of a greater sample to obtain more significant values than those showed on these research project.

Lung Function Reference Values in Healthy Korean Children / 소아알레르기및호흡기학회지

PURPOSE: Appropriate reference values are needed for assessment of pulmonary function during childhood. We performed pulmonary function test with simple computerized spirometry to establish reference values of air flow rates in healthy Korean children. METHODS: We examined 1,317 children aged 6 to 15 years at their schools by standardized method during May, 2001. The children with poor cooperation, respiratory symptom, and chronic disease were excluded. Regression analysis was applied for FVC, FEV1, PEF, FEF25-75% predicted from sex, age, standing height, weight, and body surface area. RESULTS: In 1,317 children(Male : 716, Female : 601), the distribution of height was from 106.7 cm to 173.5 cm, weight was from 16.5 kg to 75.5 kg. We could get regression equations and determinant coefficients between anthropometric parameters and air flow rates. In both sexes, height showed very close correlation with lung function variables, and FEV1 showed very close correlation with all anthropometric parameters. Reference values of pulmonary function test were generally higher in boys than in girls. CONCLUSION: After performing the pulmonary function test in healthy Korean children, we report their normal values of air flow rates and regression equations for the predicted values. Among anthropometric parameters, height showed most close correlation with lung function variables in both sexes.

Validation of the Histogram Summation Technique for Measurement Error Minimization of Respiratory Air Flow Rate / 대한의료정보학회지

The present study performed an experiment to validate the histogram summation technique developed for measurement error minimization of respiratory air flow rate2). Five sets of manual stroke operation data(MSO#1 5) of 1 [LI each were acquired at varying speeds. Selected sets of these data were used to estimate the conductance correction factors reflecting the resistance-flow character -istics. Then the correction factors were applied to different sets of the data to evaluate mean SD of the volume measurement error. When the resistance was linearly compensated without conductance correction, the relative error was 2.3% marginally within the ATS standard limit of 3%. With the histogram summation techinque applied, it has dramatically decreased down to within 1%. For a newly input flow data, the error was maintained within 1.5%. Therefore, the histogram summation techinque minimized the measurement error consistently and reproducibly. With increased number of strokes included in the correction factor estimation process, the error decreased at a rate of 0.5 [mL!S0strokesj. However, no more than 50 stroke data were necessary to keep the measurement error within 1.5%. This corresponded to only 25 MSO, thus the histogram summation technique has been demonstrated to be consistent, reproducible, and practical technique for measurement error minimization of respiratory air flow rate.

User program for PC to perform clinical spirometric test / 대한의료정보학회지

User package program run on PC was developed for clinical spirometric test, which enabled to perform popular FVC, SVC, and MVV test items in a very convenient manner. In addition, a program module for research was implemented to study breathing pattern of a patient. The program written in C language was designed to run on Windows OS, and consisted of patient information management, test procedure control, results print out, and accumulation of parameter values in a customized data base which made possible future clinical research and quality assurance. When engaged with the previously developed respiratory air flow measurement unit, the system resulted in an accurate enough performance in that FVC data showed a high correlation coefficient of higher than 0.98 with an imported system. The technician tried the present system under clinical environment and judged the convenient utility to be satisfactory. Therefore, industrialization effort is being currently made and expected to be successful.