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1.
Zhongguo Yi Liao Qi Xie Za Zhi ; 46(3): 248-253, 2022 May 30.
Article in Chinese | MEDLINE | ID: mdl-35678430

ABSTRACT

To solve the problem of real-time detection and removal of EEG signal noise in anesthesia depth monitoring, we proposed an adaptive EEG signal noise detection and removal method. This method uses discrete wavelet transform to extract the low-frequency energy and high-frequency energy of a segment of EEG signals, and sets two sets of thresholds for the low-frequency band and high-frequency band of the EEG signal. These two sets of thresholds can be updated adaptively according to the energy situation of the most recent EEG signal. Finally, we judge the level of signal interference according to the range of low-frequency energy and high-frequency energy, and perform corresponding denoising processing. The results show that the method can more accurately detect and remove the noise interference in the EEG signal, and improve the stability of the calculated characteristic parameters.


Subject(s)
Signal Processing, Computer-Assisted , Wavelet Analysis , Algorithms , Electroencephalography , Signal-To-Noise Ratio
2.
Zhongguo Yi Liao Qi Xie Za Zhi ; 46(3): 278-282, 2022 May 30.
Article in Chinese | MEDLINE | ID: mdl-35678436

ABSTRACT

Mercury sphygmomanometer based on traditional auscultation method is widely used in primary medical institutions in China, but a large amount of blood pressure data can not be directly recorded and applied in scientific research analysis, meanwhile auscultation data is the clinical standard to verify the accuracy of non-invasive electronic sphygmomanometer. Focusing on this, we designed a miniature non-invasive blood pressure measurement and verification system, which can assist doctors to record blood pressure data automatically during the process of auscultation. Through the data playback function,the software of this system can evaluate and verify the blood pressure algorithm of oscillographic method, and then continuously modify the algorithm to improve the measurement accuracy. This study introduces the hardware selection and software design process in detail. The test results show that the system meets the requirements of relevant standards and has a good application prospect.


Subject(s)
Blood Pressure Determination , Sphygmomanometers , Auscultation , Blood Pressure/physiology , Oscillometry
3.
Zhongguo Yi Liao Qi Xie Za Zhi ; 46(3): 302-306, 2022 May 30.
Article in Chinese | MEDLINE | ID: mdl-35678441

ABSTRACT

Hyperbaric oxygen therapy is a method of breathing pure oxygen or high-concentration oxygen in a highpressure environment to treat hypoxic diseases and related diseases. According to clinical verification, this therapy has an irreplaceable effect on certain diseases and has gradually become a comprehensive clinical treatment. One of the main methods of certain diseases is widely recognized by the medical field at home and abroad. The development history, treatment principles, key technologies, and future development trends of hyperbaric oxygen are discussed in detail, provide a research direction for the development of hyperbaric oxygen therapy in the future, and at the same time, it has also improved physicians' awareness of hyperbaric oxygen therapy, so as to improving Industry influence.


Subject(s)
Hyperbaric Oxygenation , Oxygen/therapeutic use , Research Design
4.
Biomacromolecules ; 23(3): 708-719, 2022 03 14.
Article in English | MEDLINE | ID: mdl-34968020

ABSTRACT

The limited utilization of reliable tools and standards for determination of the softwood kraft lignin molar mass and the corresponding molecular conformation hampers elucidation of the structure-property relationships of lignin. At issue, conventional size exclusion chromatography (SEC) is unable to robustly measure the molar mass because of a lack of calibration standards with a similar structure to lignin. In the present work, the determination of the absolute molar mass of acetylated technical lignin was revisited utilizing SEC combined with multi-angle light scattering with a band pass filter to suppress the fluorescence. Fractionated lignin isolated using sequential techniques of solvent and membrane methods was used to enhance the clarity of light-scattering profiles by narrowing the molar mass distribution of lignin fractions. Further information on the molecular conformation of derivatized samples was studied utilizing a differential viscometer, and chemical structures were identified by NMR spectroscopy analysis. Through the help of fractionation, intrinsic viscosity values were determined for the different fractions as a function of molecular weight cut-off membranes. The derivatized acetone-soluble lignin was found to possess a lower molecular weight and an extremely compact structure relative to the derivatized acetone-insoluble fraction based on a significantly lower "α" value in the Mark-Houwink-Sakurada plot (0.15 acetone-soluble vs 0.33 acetone-insoluble). The differences in geometry were supported by the linkage analysis from NMR showing the acetone-soluble part containing fewer native linkages. In both of these examples, kraft lignin behaved like a solid sphere, limiting the ability to provide entanglements between molecular chains. From this standpoint, macroscopic properties of lignin are justified with this knowledge of a dense and extremely compact structure.


Subject(s)
Acetone , Lignin , Acetone/chemistry , Lignin/chemistry , Molecular Conformation , Molecular Weight
5.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-928909

ABSTRACT

Hyperbaric oxygen therapy is a method of breathing pure oxygen or high-concentration oxygen in a highpressure environment to treat hypoxic diseases and related diseases. According to clinical verification, this therapy has an irreplaceable effect on certain diseases and has gradually become a comprehensive clinical treatment. One of the main methods of certain diseases is widely recognized by the medical field at home and abroad. The development history, treatment principles, key technologies, and future development trends of hyperbaric oxygen are discussed in detail, provide a research direction for the development of hyperbaric oxygen therapy in the future, and at the same time, it has also improved physicians' awareness of hyperbaric oxygen therapy, so as to improving Industry influence.


Subject(s)
Hyperbaric Oxygenation , Oxygen/therapeutic use , Research Design
6.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-928904

ABSTRACT

Mercury sphygmomanometer based on traditional auscultation method is widely used in primary medical institutions in China, but a large amount of blood pressure data can not be directly recorded and applied in scientific research analysis, meanwhile auscultation data is the clinical standard to verify the accuracy of non-invasive electronic sphygmomanometer. Focusing on this, we designed a miniature non-invasive blood pressure measurement and verification system, which can assist doctors to record blood pressure data automatically during the process of auscultation. Through the data playback function,the software of this system can evaluate and verify the blood pressure algorithm of oscillographic method, and then continuously modify the algorithm to improve the measurement accuracy. This study introduces the hardware selection and software design process in detail. The test results show that the system meets the requirements of relevant standards and has a good application prospect.


Subject(s)
Auscultation , Blood Pressure/physiology , Blood Pressure Determination , Oscillometry , Sphygmomanometers
7.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-928898

ABSTRACT

To solve the problem of real-time detection and removal of EEG signal noise in anesthesia depth monitoring, we proposed an adaptive EEG signal noise detection and removal method. This method uses discrete wavelet transform to extract the low-frequency energy and high-frequency energy of a segment of EEG signals, and sets two sets of thresholds for the low-frequency band and high-frequency band of the EEG signal. These two sets of thresholds can be updated adaptively according to the energy situation of the most recent EEG signal. Finally, we judge the level of signal interference according to the range of low-frequency energy and high-frequency energy, and perform corresponding denoising processing. The results show that the method can more accurately detect and remove the noise interference in the EEG signal, and improve the stability of the calculated characteristic parameters.


Subject(s)
Algorithms , Electroencephalography , Signal Processing, Computer-Assisted , Signal-To-Noise Ratio , Wavelet Analysis
8.
J Craniofac Surg ; 32(2): 744-748, 2021.
Article in English | MEDLINE | ID: mdl-33705025

ABSTRACT

BACKGROUND: Although costal cartilage has many uses and is a reliable source of cartilage for rhinoplasty procedures, donor-site complications may arise with conventional harvesting techniques. The present report reports a novel technique of harvesting costal cartilage using a specially designed scalpel and studies the use of the harvested cartilage in the reconstruction of secondary nasal deformities in patients with cleft lips. METHODS: Ten patients (7 females and 3 males) with nasal deformities secondary to cleft lip underwent rhinoplasty using this new technique at the Department of Oral and Maxillofacial Surgery, Second Hospital of Hebei Medical University, China, between May 2011 and December 2013. Clinical outcomes were evaluated with a follow-up period of 6 to 30 months. RESULTS: The new technique successfully corrected primary nasal deformities, including flat nasal tip, short columella, flaring alae, and asymmetrical nostrils. Surgeons and patients assessed the outcome to be either good or satisfactory. Patients experienced transient discomfort at the wound site but there were no major complications (such as wound infection, dehiscence, exposure, graft extrusion, and pulmonary involvement). CONCLUSIONS: The novel technique can harvest a lateral segment of costal cartilage for use in the reconstruction of nasal deformities secondary to cleft lip in a one-stage procedure, with minimal donor-site morbidity.


Subject(s)
Cleft Lip , Costal Cartilage , Rhinoplasty , China , Cleft Lip/surgery , Costal Cartilage/surgery , Female , Humans , Male , Nose/surgery , Retrospective Studies
9.
Cancer Gene Ther ; 28(7-8): 850-863, 2021 08.
Article in English | MEDLINE | ID: mdl-32753631

ABSTRACT

The aim of this study was to investigate the effect of lncRNA KCNQ1OT1 on HCC and to explore the possible underlying mechanisms. The expression levels of KCNQ1OT1, miR-149 and S1PR1 were detected by qRT-PCR assay. A dual luciferase reporter assay was used to detect the interaction between KCNQ1OT1 and miR-149, as well as miR-149 and S1PR1. The interaction between KCNQ1OT1 and miR-149 was further investigated by RNA pull-down assay. Wound healing assays and Transwell assays were carried out to determine cell migration and invasion. A xenograft tumour assay was used to validate the role of KCNQ1OT1 in vivo. KCNQ1OT1 and S1PR1 were significantly increased, but miR-149 was decreased in HCC cells. Luciferase reporter assays and RNA pull-down assays revealed that KCNQ1OT1 directly targeted miR-149. In addition, miR-149 bound to the 3'-UTR of S1PR1. Knockdown of KCNQ1OT1 or overexpression of miR-149 inhibited the invasion and migration of HCC cells. However, suppression of miR-149 could abrogate the effect of KCNQ1OT1 knockdown on the invasion and migration abilities of HCC cells. In vivo assays showed that KCNQ1OT1 knockdown suppressed tumour growth. This work suggests that lncRNA KCNQ1OT1 might act as a potential therapeutic target in HCC.


Subject(s)
Carcinoma, Hepatocellular/genetics , Liver Neoplasms/genetics , MicroRNAs/metabolism , RNA, Long Noncoding/metabolism , Sphingosine-1-Phosphate Receptors/metabolism , Animals , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Cell Movement , Humans , Liver Neoplasms/pathology , Male , Mice , Mice, Nude , Neoplasm Invasiveness , Transfection
10.
J Thorac Dis ; 11(7): 3084-3092, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31463137

ABSTRACT

BACKGROUND: To explore the risk factors and prevention methods of cervical mechanical anastomotic fistula and stenosis after the radical resection of esophageal cancer. METHODS: From March 2018 to November 2018, 128 patients undergoing mechanical anastomosis of esophageal cancer were selected from the Department of Thoracic Surgery of The First Affiliated Hospital of Zhengzhou University. All the enrolled patients were operated on using the Mckeown method, and a retrospective study was conducted. Data for preoperative and postoperative test indices, intraoperative embedding materials, postoperative complications, and preoperative and postoperative treatment were collected, and the relationship between various factors and the incidence of cervical anastomotic fistula and stenosis was analysed. Univariate analysis was conducted using t tests or Fisher's exact probability method, and multivariate analysis was conducted using logistic regression models. RESULTS: All 128 patients successfully underwent surgery without dying. The enrolled patients were evaluated using the Stooler classification, with 28 patients having grade 0, 41 patients having grade 1, 34 patients having grade 2, 21 patients having grade 3, and 4 patients having grade 4 stenosis. Patients with stenosis of grade 3 or above had obvious choking sensation, which could only be relieved by balloon dilation. Symptoms in all patients with stenosis were relieved by balloon dilation. There were no significant differences between the two groups regarding embedding materials, preoperative choking history, history of alcohol consumption, history of hypertension, history of coronary heart disease, history of diabetes, postoperative calcium concentration, average albumin concentration, average platelet concentration, body mass index, anastomotic fistula, preoperative chemotherapy, postoperative chemotherapy, or postoperative cough (P>0.05). There were significant differences in postoperative reflux (χ2=11.338, P<0.05) and scar constitution (χ2=12.497, P<0.05). The effects of embedding materials in patients with anastomotic fistula were significantly different (χ2=4.372, P<0.05). CONCLUSIONS: Postoperative reflux and scar constitution may be risk factors for postoperative anastomotic stenosis after resection of esophageal cancer. There was almost no difference in the effects on esophageal anastomotic stenosis between embedding materials and the omentum majus, but Neoveil® may have certain advantages in preventing cervical anastomotic fistula, and thus may have certain clinical application value.

11.
BMC Genomics ; 20(1): 323, 2019 Apr 29.
Article in English | MEDLINE | ID: mdl-31035925

ABSTRACT

BACKGROUND: Artificial induction of mutagenesis is effective for genetic resource innovation and breeding. However, the traditional mutation methods for fish breeding are not convenient or safe for daily use. Hence, development of a simple, safe and effective mutagenesis method with a high mutation rate and applicability to multiple fish species, is needed. RESULTS: We reported the first successful mutagenesis in a marine aquaculture fish species, Japanese flounder, Paralichthys olivaceus, using a novel atmosphere and room temperature plasma (ARTP) mutagenesis tool. ARTP treatment time was optimized for the fertilized eggs and sperm, respectively. Eggs fertilized for 60 min were treated by ARTP with a radio-frequency power input of 120 W, and the ARTP treatment time was 25 min. Under an ARTP radio-frequency power input of 200 W, the optimal treatment time for sperm diluted with Ringer's solution by 1:40 v/v was 10 min. The ARTP-treated group presented differences in morphological traits such as body height, total length among individuals at day 90 after hatching. Whole-genome sequencing was used to reveal the mutation features of ARTP-treated individuals collected at day 120 after hatching. In total, 69.25Gb clean data were obtained from three controls and eight randomly selected ARTP-treated individuals, revealing 240,722 to 322,978 SNPs and 82,149 to 86,798 InDels located in 17,394~18,457 and 12,907~13,333 genes, respectively. The average mutation rate reached 0.064% at the genome level. Gene ontology clustering indicated that genes associated with cell components, binding function, catalytic activity, cellular process, metabolic process and biological regulation processes had higher mutation rates. CONCLUSIONS: ARTP mutagenesis is a useful method for breeding of fish species to accelerate the selection of economically important traits that would benefit the aquaculture industry, given the variety of mutations detected.


Subject(s)
Flounder/genetics , Plasma Gases , Radio Waves , Animals , Body Size , Breeding , Cluster Analysis , Flounder/growth & development , INDEL Mutation , Japan , Male , Mutagenesis , Polymorphism, Single Nucleotide , Spermatozoa/radiation effects , Temperature , Whole Genome Sequencing , Zygote/radiation effects
12.
Huan Jing Ke Xue ; 37(2): 630-7, 2016 Feb 15.
Article in Chinese | MEDLINE | ID: mdl-27363154

ABSTRACT

To reveal the dynamic succession of microbial community structure along with time in bio-denitrification reactor, a continuous flow reactor containing immobilized heterotrophic nitrification-aerobic denitrification bacterium Burkholderia sp. YX02 was taken as a model. The microbial community structure in the bioreactor was analyzed by PCR-DCGE, and its correlations with environmental factors such as pH, NH4+ -N, NO2- -N, NO3- -N and COD were simultaneously investigated. The results showed that the microbial community was relatively rich during the early stage of 18 days. The similarity of community structure in different stages was not orderly declining with the operation. In addition, the structural similarity in adjacent stages firstly increased, then decreased, and eventually tended to be stable. Shannon-Wiener index firstly descended significantly, and then ascended with new microbial community emerging at the later stage. UPGMA clustering analysis roughly divided the process into three periods with certain relationship. Principal component analysis showed that during the operation of the bioreactor predominant bacterial community formed steadily and new microbial community dominated by Burkholderia sp. YX02 emerged at the later stage of the operation. Canonical correspondence analysis certificated that the structure of microbial community was most obviously affected by NO2- -N, followed by NO3- -N, NH4+ -N and COD, and pH had the least effect.


Subject(s)
Bioreactors/microbiology , Burkholderia/isolation & purification , Denitrification , Microbial Consortia , Nitrification , Heterotrophic Processes
13.
J Thorac Dis ; 7(9): 1580-7, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26543605

ABSTRACT

BACKGROUND: To evaluate the feasibility, safety and efficacy of computed tomography (CT)-guided microcoil localization for small pulmonary lesions prior to thoracoscopic resection. METHODS: We retrospectively reviewed the medical data of patients with pulmonary solid nodules and ground-glass opacity (GGO) who underwent CT-guided microcoil localization prior to thoracoscopic surgery. The microcoil was deployed with the proximal end of the microcoil coiling beyond the parietal pleura while the distal part anchoring in the lung parenchyma. After marking with microcoil, the pulmonary lesions were removed by thoracoscopic surgery. RESULTS: CT-guided microcoil placements were successful in all 98 lesions, including 14 solid nodules, 11 part-solid GGO, and 73 pure GGO. The mean distance from the lesions to the pleura surface was 11.1±6.6 mm. Eighty-four microcoils (85.7%) were successfully placed with the tails coiled beyond the parietal pleura. Seventeen patients (17.3%) had mild complications after the procedure of localization. Thirteen patients with asymptomatic pneumothorax, only one patient required further thoracentesis, four patients with pulmonary hematoma. Removal of the pulmonary lesions was successful in all patients. Sixty-six lesions (67.3%) were localized through the proximal end of the microcoil beyond the visceral pleura by visual inspection, 29 lesions were localized by palpation of the microcoil or the nodule, and 3 lesions had dislocation of the microcoil, resulting in a success rate of 96.9% for intraoperative localization. CONCLUSIONS: CT-guided microcoil localization prior to thoracoscopic resection is a feasible, safe, and effective method for localization of pulmonary small nodules and GGO.

14.
J Microbiol Biotechnol ; 25(12): 1977-88, 2015 Dec 28.
Article in English | MEDLINE | ID: mdl-26370802

ABSTRACT

ß-1,3-glucanosyltransferases play essential roles in cell wall biosynthesis in yeast. Kluyveromyces lactis has six putative ß-1,3-glucanosyltransferase genes. KlGAS1-1 and KlGAS1-2 are homologs of Saccharomyces cerevisiae gene GAS1. RT-qPCR indicated the transcription level of KlGAS1-1 was significantly reduced while heterologous protein (thermostable xylanase B) secretion was enhanced during medium optimization. To evaluate if these two events were related, and to improve xylanase B secretion in K. lactis, we constructed KlGAS1-1 and KlGAS1-2 single deletion strains and double deletion strain, respectively. KlGAS1-1 gene deletion resulted in the highest xylanase B activity among the three mutants. Only the double deletion strain showed morphology similar to that of the GAS1 deletion mutant in S. cerevisiae. The two single deletion strains differed in terms of cell wall thickness and xylanase B secretion. Transcription levels of ß-1,3-glucanosyltransferase genes and genes related to protein secretion and transport were assayed. The ß-1,3-glucanosyltransferase genes displayed transcription complementation in the cell wall synthesis process. KlGAS1-1 and KlGAS1-2 affected transcription levels of secretion- and transport-related genes. Differences in protein secretion ratio among the three deletion strains were associated with changes of transcription levels of secretion- and transport-related genes. Our findings indicate that KlGAS1-1 deletion is an effective tool for enhancing industrial-scale heterologous protein secretion in K. lactis.


Subject(s)
Endo-1,4-beta Xylanases/biosynthesis , Endo-1,4-beta Xylanases/metabolism , Kluyveromyces/enzymology , Kluyveromyces/genetics , Membrane Glycoproteins/genetics , Membrane Glycoproteins/metabolism , Cell Wall/ultrastructure , Endo-1,4-beta Xylanases/genetics , Gene Deletion , Glucan Endo-1,3-beta-D-Glucosidase/genetics , Glucan Endo-1,3-beta-D-Glucosidase/metabolism , Kluyveromyces/ultrastructure , Metabolic Engineering/methods , Recombinant Proteins/biosynthesis , Recombinant Proteins/genetics , Recombinant Proteins/metabolism
15.
Environ Microbiol ; 14(7): 1722-9, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22360568

ABSTRACT

Magnetotactic bacteria synthesize magnetic particles called magnetosomes that cause them to orient to their external magnetic fields. However, the physiological significance and other possible functions of these magnetosomes have not been explored in detail. In this study, we have investigated the biological functions of magnetosomes with respect to their ability to scavenge reactive oxygen species (ROS) in Magnetospirillum gryphiswaldense MSR-1. To assess the changes in ROS levels under different conditions, cells were cultured under aerobic or micro-aerobic conditions in medium containing high and low amounts of iron. To ensure that the observed results were not due to nonspecific interactions, reactions were carried out using a mutant deficient in synthesizing magnetite (mamO-deficient mutant), its complementary strain or the wild-type MSR-1. We observed that the levels of intercellular ROS under micro-aerobic conditions with high-iron medium were much higher when the non-synthetic Fe(3) O(4) crystals mutant Mu21-415 was employed for the assay, compared with the wild-type or complementary strain, or when conditions were aerobic with low-iron medium. These results indicated that magnetosomes function in the scavenging of intracellular ROS. Furthermore, we have demonstrated that the magnetosomes exhibit peroxidase-like properties, by using the earlier reported in vitro horseradish peroxidase assay for artificial magnetic nanoparticles. In addition to possessing peroxidase-like activity, the magnetosomes also exhibited a more enzymatic kinetic response, suggesting that proteins on the membranes of the magnetosomes likely contribute to the enzymatic activity. This is the first study to demonstrate that magnetosomes play an important role in decreasing or eliminating ROS.


Subject(s)
Iron/metabolism , Magnetosomes/metabolism , Magnetospirillum/metabolism , Reactive Oxygen Species/metabolism , Bacterial Proteins/metabolism , Culture Media/chemistry , Ferrosoferric Oxide/metabolism , Hydrogen-Ion Concentration , Peroxidase/metabolism , Temperature
16.
J Integr Plant Biol ; 51(4): 409-13, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19341408

ABSTRACT

Prunus necrotic ring spot virus (PNRSV) and grapevine fanleaf virus (GFLV) were detected by fluoroimmunoassay using bacterial magnetic particles (BMPs), and a double antibody sandwich enzyme linked immunosorbent assay (DAS-ELISA). For the fluoroimmunoassay, fluorescein isothiocyanate labeled anti-PNRSV antibody or anti-GFLV antibody was conjugated onto BMPs of Magnetospirillum gryphiswaldense MSR-1. With this method, a very low minimum antigen concentration (1 x 10(6) dilution of the original sample concentration) could be detected. Using DAS-ELISA, the minimum antigen detection concentration was the original sample concentration. Thus, comparing these two methods, a BMP-based method could increase the sensitivity up to six orders of magnitude (10(6)) higher than an ELISA-based method of detection PNRSV and GFLV.


Subject(s)
Bacteria/chemistry , Fruit/virology , Magnetics/methods , Plant Viruses/isolation & purification , Prunus/virology , Trees/virology , Vitis/virology , Antibodies , Electrophoresis, Polyacrylamide Gel , Enzyme-Linked Immunosorbent Assay , Fluoroimmunoassay , Immobilized Proteins/metabolism
17.
Appl Biochem Biotechnol ; 158(2): 398-407, 2009 Aug.
Article in English | MEDLINE | ID: mdl-18712288

ABSTRACT

A genetically engineered Escherichia coli was developed as the source of enzyme for rapidly quantifying glutamine. E. coli BL21 (DE3) cells overexpressing a glutamine synthetase from Bacillus subtilis were prepared as tube aliquots and used in a small volume of nontoxic mixture. The current method was compared to high performance liquid chromatography analysis, Sigma kit (GLN-1) and Mecke method. The method is applicable to a wide range of glutamine concentrations (0.05-2.5 mM) and correlates well to the detection results obtained from high performance liquid chromatography (Pearson correlation is 0.978 at the 0.01 level). Moreover, the whole assay procedure takes less than 15 min and uses nontoxic reagents, so it can be applied to monitor glutamine production and utilization conveniently.


Subject(s)
Escherichia coli/metabolism , Gene Expression Regulation, Enzymologic , Glutamate-Ammonia Ligase/metabolism , Glutamine/analysis , Glutamine/metabolism , Bacillus subtilis/enzymology , Bacillus subtilis/genetics , Chromatography, High Pressure Liquid , Escherichia coli/enzymology , Escherichia coli/genetics , Genetic Engineering , Glutamate-Ammonia Ligase/genetics
18.
Appl Microbiol Biotechnol ; 79(3): 389-97, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18425510

ABSTRACT

Magnetotactic bacteria are difficult to grow under defined conditions in culture, which has presented a major obstacle to commercial application of magnetosomes. We studied the relationships among the cell growth, magnetosome formation, dissolved oxygen concentration (DO), and the ability to supply oxygen to the cells. Mass culture of Magnetospirillum gryphiswaldense MSR-1 for the production of magnetosomes was established in a 42-L fermentor under the following conditions: (1) sterile air was the sole gas supplied in the fermentor, and DO could be regulated at any level below 10% saturation by cascading the stir rate to DO, (2) to resolve the paradoxical situation that the cell growth requires higher DO whereas magnetosome formation requires low DO below the detectable range of regular oxygen electrode, DO was controlled to optimal level using the change of cell growth rate, rather than reading from the highly sensitive oxygen electrode, as the signal for determining appropriate DO, and (3) timing and rate of supplying the substrates were determined by measuring cell density and Na-lactate concentration. Under these conditions, cell density (OD565) of strain MSR-1 reached 7.24 after 60-h culture in a 42-L fermentor, and cell yield (dry weight) was 2.17 g/L, the highest yield so far being reported. The yield of magnetosomes (dry weight) was 41.7 mg/L and 16.7 mg/L/day, which were 2.8 and 2.7 times higher than the previously reported yields.


Subject(s)
Bioreactors/microbiology , Magnetics , Magnetospirillum/growth & development , Magnetospirillum/metabolism , Oxygen/metabolism , Air , Biomass , Cell Culture Techniques/methods , Fermentation , Magnetospirillum/cytology
19.
Zhongguo Yi Liao Qi Xie Za Zhi ; 32(6): 455-8, 2008 Nov.
Article in Chinese | MEDLINE | ID: mdl-19253585

ABSTRACT

This article introduces a measuring method for invasive blood pressure based on SecWave technology and a testing method of effectiveness based on IBP database and simulator. Besides, quantified indexes are set out for the accuracy evaluation, such as static pressure accuracy, accuracy of dynamic pressure pulse wave recognition, pulse rate and the response time, so as to provide an important reference method of effectively objective evaluation for invasive blood pressure measurements.


Subject(s)
Blood Pressure Determination/instrumentation , Blood Pressure Determination/methods , Electronic Data Processing/methods , Algorithms , Humans
20.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-309550

ABSTRACT

This article introduces a measuring method for invasive blood pressure based on SecWave technology and a testing method of effectiveness based on IBP database and simulator. Besides, quantified indexes are set out for the accuracy evaluation, such as static pressure accuracy, accuracy of dynamic pressure pulse wave recognition, pulse rate and the response time, so as to provide an important reference method of effectively objective evaluation for invasive blood pressure measurements.


Subject(s)
Humans , Algorithms , Electronic Data Processing , Methods , Blood Pressure Determination , Methods
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