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1.
Appl Microbiol Biotechnol ; 108(1): 123, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38229404

RESUMO

There is a growing interest in perfusion or continuous processes to achieve higher productivity of biopharmaceuticals in mammalian cell culture, specifically Chinese hamster ovary (CHO) cells, towards advanced biomanufacturing. These intensified bioprocesses highly require concentrated feed media in order to counteract their dilution effects. However, designing such condensed media formulation poses several challenges, particularly regarding the stability and solubility of specific amino acids. To address the difficulty and complexity in relevant media development, the biopharmaceutical industry has recently suggested forming dipeptides by combining one from problematic amino acids with selected pairs to compensate for limitations. In this study, we combined one of the lead amino acids, L-tyrosine, which is known for its poor solubility in water due to its aromatic ring and hydroxyl group, with glycine as the partner, thus forming glycyl-L-tyrosine (GY) dipeptide. Subsequently, we investigated the utilization of GY dipeptide during fed-batch cultures of IgG-producing CHO cells, by changing its concentrations (0.125 × , 0.25 × , 0.5 × , 1.0 × , and 2.0 ×). Multivariate statistical analysis of culture profiles was then conducted to identify and correlate the most significant nutrients with the production, followed by in silico model-guided analysis to systematically evaluate their effects on the culture performance, and elucidate metabolic states and cellular behaviors. As such, it allowed us to explain how the cells can more efficiently utilize GY dipeptide with respect to the balance of cofactor regeneration and energy distribution for the required biomass and protein synthesis. For example, our analysis results uncovered specific amino acids (Asn and Gln) and the 0.5 × GY dipeptide in the feed medium synergistically alleviated the metabolic bottleneck, resulting in enhanced IgG titer and productivity. In the validation experiments, we tested and observed that lower levels of Asn and Gln led to decreased secretion of toxic metabolites, enhanced longevity, and elevated specific cell growth and titer. KEY POINTS: • Explored the optimal Tyr dipeptide for the enhanced CHO cell culture performance • Systematically analyzed effects of dipeptide media by model-guided approach • Uncovered synergistic metabolic utilization of amino acids with dipeptide.


Assuntos
Aminoácidos , Técnicas de Cultura Celular por Lotes , Cricetinae , Animais , Cricetulus , Células CHO , Meios de Cultura/química , Técnicas de Cultura Celular por Lotes/métodos , Aminoácidos/metabolismo , Tirosina , Dipeptídeos , Imunoglobulina G , Simulação por Computador
2.
Metab Eng ; 73: 114-123, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35798249

RESUMO

Proposed herein is a systematic media design framework that combines multivariate statistical approaches with in silico analysis of a genome-scale metabolic model of Chinese hamster ovary cell. The framework comprises sequential modules including cell culture and metabolite data collection, multivariate data analysis, in silico modeling and flux prediction, and knowledge-based identification of target media components. Two monoclonal antibody-producing cell lines under two different media conditions were used to demonstrate the applicability of the framework. First, the cell culture and metabolite profiles from all conditions were generated, and then statistically and mechanistically analyzed to explore combinatorial effects of cell line and media on intracellular metabolism. As a result, we found a metabolic bottleneck via a redox imbalance in the TCA cycle in the poorest growth condition, plausibly due to inefficient coenzyme q10-q10h2 recycling. Subsequent in silico simulation allowed us to suggest q10 supplementation to debottleneck the imbalance for the enhanced cellular energy state and TCA cycle activity. Finally, experimental validation was successfully conducted by adding q10 in the media, resulting in increased cell growth. Taken together, the proposed framework rationally identified target nutrients for cell line-specific media design and reformulation, which could greatly improve cell culture performance.


Assuntos
Técnicas de Cultura de Células , Modelos Biológicos , Animais , Células CHO , Simulação por Computador , Cricetinae , Cricetulus , Meios de Cultura
3.
Molecules ; 27(16)2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36014542

RESUMO

The 3D cell migration assay was developed for the evaluation of drugs that inhibit cell migration using high throughput methods. Wound-healing assays have commonly been used for cell migration assays. However, these assays have limitations in mimicking the in vivo microenvironment of the tumor and measuring cell viability for evaluation of cell migration inhibition without cell toxicity. As an attempt to manage these limitations, cells were encapsulated with Matrigel on the surface of the pillar, and an analysis of the morphology of cells attached to the pillar through Matrigel was performed for the measurement of cell migration. The micropillar/microwell chips contained 532 pillars and wells, which measure the migration and viability of cells by analyzing the roundness and size of the cells, respectively. Cells seeded in Matrigel have a spherical form. Over time, cells migrate through the Matrigel and attach to the surface of the pillar. Cells that have migrated and adhered have a diffused shape that is different from the initial spherical shape. Based on our analysis of the roundness of the cells, we were able to distinguish between the diffuse and spherical shapes. Cells in Matrigel on the pillar that were treated with migration-inhibiting drugs did not move to the surface of the pillar and remained in spherical forms. During the conduct of experiments, 70 drugs were tested in single chips and migration-inhibiting drugs without cell toxicity were identified. Conventional migration assays were performed using transwell for verification of the four main migration-inhibiting drugs found on the chip.


Assuntos
Técnicas de Cultura de Células , Ensaios de Triagem em Larga Escala , Técnicas de Cultura de Células/métodos , Linhagem Celular Tumoral , Ensaios de Migração Celular , Movimento Celular , Sobrevivência Celular
4.
Opt Express ; 24(2): A350-7, 2016 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-26832587

RESUMO

CdSe/CdS/ZnS core-shell-shell quantum dots (QDs) were synthesized by using a solution process. High-resolution transmission electron microscopy images and energy dispersive spectroscopy profiles confirmed that stoichiometric CdSe/CdS/ZnS core-shell-shell QDs were formed. Ultraviolet-visible absorption and photoluminescence (PL) spectra of CdSe/CdS/ZnS core-shell-shell QDs showed the dominant excitonic transitions from the ground electronic subband to the ground hole subband (1S(e)-1S(3/2)(h)). The PL mechanism is suggested; the carriers generated by the exciting high-energy photons in the shell region are relaxed to the band-edge states of the core region and recombined to emit lower-energy photons. The activation energy of the carriers confined in the CdSe/CdS/ZnS core-shell-shell QDs, as obtained from temperature-dependent PL spectra, was 200 meV. The quantum efficiency of the CdSe/CdS/ZnS core-shell-shell QDs at 300 K was estimated to be approximately 57%.

5.
Arch Toxicol ; 88(8): 1607-18, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24525745

RESUMO

The unique properties of nanoparticles and biological systems are important factors affecting the biological response following nanoparticle exposure. Iron oxide nanoparticles are classified mainly as magnetite (M-FeNPs) and maghemite (NM-FeNPs). In our previous study, NM-FeNPs induced autophagic cell death in RAW264.7, a murine peritoneal macrophage cell line, which has excellent lysosomal activity. In this study, we compared the toxicity of M-FeNPs and NM-FeNPs in MH-S, a murine alveolar macrophage cell line, which has relatively low lysosomal activity. At 24 h post-exposure, M-FeNPs decreased cell viability and ATP production, and elevated the levels of reactive oxygen species, nitric oxide, and pro-inflammatory cytokines to a higher extent than NM-FeNPs. Damage of mitochondria and the endoplasmic reticulum and the down-regulation of mitochondrial function and transcription-related genes were also higher in cells exposed to M-FeNPs than in cells exposed to NM-FeNPs (50 µg/ml). In addition, cells exposed to M-FeNPs (50 µg/ml) showed an increase in the number of autophagosome-like vacuoles, whereas cells exposed to NM-FeNPs formed large vacuoles in the cytosol. However, an autophagy-related molecular response was not induced by exposure to either FeNPs, unlike the results seen in our previous study with RAW264.7 cells. We suggest that M-FeNPs induced higher toxicity compared to NM-FeNPs in MH-S cells, and lysosomal activity plays an important role in determining cell death pathway.


Assuntos
Compostos Férricos/toxicidade , Macrófagos Alveolares/efeitos dos fármacos , Nanopartículas de Magnetita/toxicidade , Trifosfato de Adenosina/metabolismo , Animais , Autofagia/efeitos dos fármacos , Técnicas de Cultura de Células , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/ultraestrutura , Camundongos , Microscopia Eletrônica de Transmissão , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo
6.
Trends Biotechnol ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38548556

RESUMO

Genome-scale metabolic models (GEMs) of Chinese hamster ovary (CHO) cells are valuable for gaining mechanistic understanding of mammalian cell metabolism and cultures. We provide a comprehensive overview of past and present developments of CHO-GEMs and in silico methods within the flux balance analysis (FBA) framework, focusing on their practical utility in rational cell line development and bioprocess improvements. There are many opportunities for further augmenting the model coverage and establishing integrative models that account for different cellular processes and data for future applications. With supportive collaborative efforts by the research community, we envisage that CHO-GEMs will be crucial for the increasingly digitized and dynamically controlled bioprocessing pipelines, especially because they can be successfully deployed in conjunction with artificial intelligence (AI) and systems engineering algorithms.

7.
Plant Pathol J ; 39(1): 52-61, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36760049

RESUMO

Fire blight, caused by Erwinia amylovora, is one of the major bacterial disease of apple and pear, causing enormous economic losses worldwide. Several control measures against E. amylovora have been reported till date, however, none of them have proved to be effective significantly against the pathogen. In this study, mechanisms of the copper-based control agents (CBCAs): copper oxychloride (COCHL), copper oxide (COX), copper hydroxide (CHY), copper sulfate basic (CSB), and tribasic copper sulfate (TCS) and their disease severity reduction efficacy against E. amylovora were analyzed. Bis-1,3-dibutylbarbituric acid trimethine oxonol, carboxyl fluorescein diacetate succinimidyl ester, and 5-cyano-2,3-ditolyl tetrazolium chloride staining were used to check the damage of membrane potential, cytoplasmic pHin, and respiration of CBCAs-treated E. amylovora, respectively. High disturbance in the membrane potential of E. amylovora was found under COX and COCHL treatments. Similarly, higher significant changes in the inner cytoplasmic pHin were observed under COX, COCHL, and TCS treatment. CHY and COCHL-treated E. amylovora showed a significant reduction in respiration. In vitro bioassay results revealed that CHY, CSB, and TCS at 2,000 ppm reduced the severity of fire blight both in pre- and post-treatment of CBCAs in immature apple fruits and seedlings. Overall, the most effective CBCAs against E. amylovora could be CHY at 2,000 ppm as its showed inhibition mechanisms and disease severity reduction.

8.
Biotechnol J ; 18(12): e2300126, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37605365

RESUMO

Designing and selecting cell culture media along with their feeding are a key strategy to maximize culture performance in biopharmaceutical processes. However, the sensitivity of mammalian cells to their culture environment necessitates specific nutritional requirements for their growth and the production of high-quality proteins such as antibodies, depending on the cell lines and operational conditions employed. In this regard, previously we developed a data-driven and in-silico model-guided systematic framework to investigate the effect of growth media on Chinese hamster ovary (CHO) cell culture performance, allowing us to design and reformulate basal media. To expand our exploration for media development research, we evaluated two chemically defined feed media, A and B, using a monoclonal antibody-producing CHO-K1 cell line in ambr15 bioreactor runs. We observed a significant impact of the feed media on various aspects of cell culture, including growth, longevity, viability, productivity, and the production of toxic metabolites. Specifically, the concentrated feed A was inadequate in sustaining prolonged cell culture and achieving high titers when compared to feed B. Within our framework, we systematically investigated the major metabolic bottlenecks in the tricarboxylic acid cycle and relevant amino acid transferase reactions. This analysis identified target components that play a crucial role in alleviating bottlenecks and designing highly productive cell cultures, specifically the addition of glutamate to feed A and asparagine to feed B. Based on our findings, we reformulated the feeds by adjusting the amounts of the targeted amino acids and successfully validated the effectiveness of the strategy in promoting cell growth, life span, and/or titer.


Assuntos
Anticorpos Monoclonais , Técnicas de Cultura de Células , Cricetinae , Animais , Cricetulus , Células CHO , Aminoácidos/metabolismo , Meios de Cultura/química
9.
Comput Struct Biotechnol J ; 21: 3736-3745, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37547082

RESUMO

The biomass equation is a critical component in genome-scale metabolic models (GEMs): it is used as the de facto objective function in flux balance analysis (FBA). This equation accounts for the quantities of all known biomass precursors that are required for cell growth based on the macromolecular and monomer compositions measured at certain conditions. However, it is often reported that the macromolecular composition of cells could change across different environmental conditions and thus the use of the same single biomass equation in FBA, under multiple conditions, is questionable. Herein, we first investigated the qualitative and quantitative variations of macromolecular compositions of three representative host organisms, Escherichia coli, Saccharomyces cerevisiae and Cricetulus griseus, across different environmental/genetic variations. While macromolecular building blocks such as RNA, protein, and lipid composition vary notably, changes in fundamental biomass monomer units such as nucleotides and amino acids are not appreciable. We also observed that flux predictions through FBA is quite sensitive to macromolecular compositions but not the monomer compositions. Based on these observations, we propose ensemble representations of biomass equation in FBA to account for the natural variation of cellular constituents. Such ensemble representations of biomass better predicted the flux through anabolic reactions as it allows for the flexibility in the biosynthetic demands of the cells. The current study clearly highlights that certain component of the biomass equation indeed vary across different conditions, and the ensemble representation of biomass equation in FBA by accounting for such natural variations could avoid inaccuracies that may arise from in silico simulations.

10.
Asian Spine J ; 12(6): 992-997, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30322258

RESUMO

STUDY DESIGN: Feasibility study. PURPOSE: To evaluate the feasibility of using serum pentosidine level as a potential marker for osteoporotic vertebral compression fracture (OVCF). OVERVIEW OF LITERATURE: A review of previous studies suggests a negative correlation between serum pentosidine concentration and bone strength. However, it is unclear whether serum pentosidine level might be a potential marker of OVCF in Koreans. METHODS: Forty patients who underwent bone mineral density examination were included in this study, and their serum pentosidine levels were prospectively analyzed. Serum pentosidine level was evaluated using enzyme-linked immunosorbent assay. Among all the patients, 11 with OVCF were assigned to the vertebral fracture group and 29 who did not have vertebral fracture were included in the non-fracture group. In addition, we used the Fracture Risk Assessment (FRAX) tool Korean version for assessing the 10-year probability of fracture. RESULTS: There was a statistically significant difference in the mean serum pentosidine level (p=0.04) of the vertebral fracture group (110.8 ng/mL) and the non-fracture group (64.3 ng/mL). Logistic regression analyses showed that serum pentosidine was significantly associated with OVCF. The vertebral fracture group had significantly higher 10-year probability of major osteoporotic fracture as per FRAX than the non-fracture group. There was a positive correlation between pentosidine level and FRAX results (r=0.35, p=0.02). CONCLUSIONS: These results suggest that increased serum pentosidine level could be a potential marker for OVCF.

11.
J Biophotonics ; 11(11): e201800081, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29799675

RESUMO

Current electroencephalogram (EEG) based-consciousness monitoring technique is vulnerable to specific clinical conditions (eg, epilepsy and dementia). However, hemodynamics is the most fundamental and well-preserved parameter to evaluate, even under severe clinical situations. In this study, we applied near-infrared spectroscopy (NIRS) system to monitor hemodynamic change during ketamine-induced anesthesia to find its correlation with the level of consciousness. Oxy-hemoglobin (OHb) and deoxy-hemoglobin concentration levels were continuously acquired throughout the experiment, and the reflectance ratio between 730 and 850 nm was calculated to quantify the hemodynamic changes. The results showed double peaks of OHb concentration change during ketamine anesthesia, which seems to be closely related to the consciousness state of the rat. This finding suggests the possibility of NIRS based-hemodynamic monitoring as a supplementary parameter for consciousness monitoring, compensating drawbacks of EEG signal based monitoring.


Assuntos
Anestesia , Circulação Cerebrovascular/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Ketamina/farmacologia , Animais , Eletroencefalografia/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley
12.
PLoS One ; 12(4): e0175191, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28384227

RESUMO

The thalamus is thought to relay peripheral sensory information to the somatosensory cortex in the parietal lobe. Long-range thalamo-parietal interactions play an important role in inducing the effect of anesthetic. However, whether these interaction changes vary with different levels of anesthesia is not known. In the present study, we investigated the influence of different levels of isoflurane-induced anesthesia on the functional connectivity between the thalamus and the parietal region. Microelectrodes were implanted in rats to record local field potentials (LFPs). The rats underwent different levels of isoflurane anesthesia [deep anesthesia: isoflurane (ISO) 2.5 vol%, light anesthesia (ISO 1 vol%), awake, and recovery state] and LFPs were recorded from four different brain areas (left parietal, right parietal, left thalamus, and right thalamus). Partial directed coherence (PDC) was calculated for these areas. With increasing depth of anesthesia, the PDC in the thalamus-to-parietal direction was significantly increased mainly in the high frequency ranges; however, in the parietal-to-thalamus direction, the increase was mainly in the low frequency band. For both directions, the PDC changes were prominent in the alpha frequency band. Functional interactions between the thalamus and parietal area are augmented proportionally to the anesthesia level. This relationship may pave the way for better understanding of the neural processing of sensory inputs from the periphery under different levels of anesthesia.


Assuntos
Anestésicos Inalatórios/farmacologia , Isoflurano/farmacologia , Lobo Parietal/efeitos dos fármacos , Tálamo/efeitos dos fármacos , Animais , Masculino , Microeletrodos , Lobo Parietal/fisiologia , Ratos , Ratos Long-Evans , Tálamo/fisiologia
13.
J Nanosci Nanotechnol ; 16(6): 6271-4, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27427701

RESUMO

X-ray photoelectron spectroscopy spectra showed that the synthesized elements of the CdSe/CdS/ ZnS QDs were Cd, Se, Zn, and S. Organic bistable devices (OBDs) containing CdSe/CdS/ZnS quantum dots (QDs) and a poly(methylmethacrylate) (PMMA) layer were fabricated on indium-tin-oxide (ITO)-deposited glass substrates. Current-voltage (I-V) curves showed that the memory margin of the Al/(CdSe/CdS/ZnS QDs) embedded in PMMA layer/ITO device at 300 K was larger than that of the device without a ZnS shell layer. The retention time of the OBDs was above 1 x 10(4) s, indicative of the stability of the device. The memory mechanisms were described by using charge trapping and tunneling processes on the basis of the energy diagram and the I-V curves.

14.
Biomed Opt Express ; 7(10): 4114-4124, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27867719

RESUMO

We aimed to investigate experimentally how anesthetic levels affect cerebral metabolism measured by near-infrared spectroscopy (NIRS) and to identify a robust marker among NIRS parameters to discriminate various stages of anesthetic depth in rats under isoflurane anesthesia. In order to record the hemodynamic changes and local field potential (LFP) in the brain, fiber-optic cannulae and custom-made microelectrodes were implanted in the frontal cortex of the skull. The NIRS and LFP signals were continuously monitored before, during and after isoflurane anesthesia. As isoflurane concentration is reduced, the level of oxyhemoglobin and total hemoglobin concentrations of the frontal cortex decreased gradually, while deoxyhemoglobin increased. The reflectance ratio between 730nm and 850nm and burst suppression ratio (BSR) correspond similarly with the change of oxyhemoglobin during the variation of isoflurane concentration. These results suggest that NIRS signals in addition to EEG may provide a possibility of developing a new anesthetic depth index.

15.
Neurosci Lett ; 627: 18-23, 2016 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-27230989

RESUMO

Anesthesia is thought to be mediated by inhibiting the integration of information between different areas of the brain. Long-range thalamo-cortical interaction plays a critical role in inducing anesthesia-related unconsciousness. However, it remains unclear how this interaction change according to anesthetic depth. In this study, we aimed to investigate how different levels of anesthesia affect thalamo-frontal interactions. Prior to the experiment, electrodes were implanted to record local field potentials (LFPs). Isoflurane (ISO) was administered and LFPs were measured in rats from four different brain areas (left frontal, right frontal, left thalamus and right thalamus) at four different anesthesia levels: awake, deep (ISO 2.5vol%), light (ISO 1vol%) and recovery. Spectral granger causality (Spectral-GC) were calculated at the measured areas in accordance with anesthetic levels. Anesthesia led to a decrease in connectivity in the thalamo-frontal direction and an increase in connectivity in the frontal-thalamic direction. The changes in thalamo-frontal functional connectivity were prominent during deep anesthesia at high frequency bands. The connection strengths between the thalamus and the frontal area changed depending on the depth of anesthesia. The relationships between anesthetic levels and thalamo-frontal activity may shed light on the neural mechanism by which different levels of anesthesia act.


Assuntos
Anestésicos Inalatórios/administração & dosagem , Lobo Frontal/efeitos dos fármacos , Lobo Frontal/fisiologia , Isoflurano/administração & dosagem , Tálamo/efeitos dos fármacos , Tálamo/fisiologia , Animais , Ondas Encefálicas/efeitos dos fármacos , Masculino , Ratos , Ratos Long-Evans , Processamento de Sinais Assistido por Computador
16.
Chemosphere ; 59(6): 845-52, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15811413

RESUMO

A treatability study was conducted using sea sand spiked with 3% or 6% (w/w) of Arabian light crude oil to determine the most effective bioremediation strategies for different levels of contamination. The sea sand used in the study was composed of gravel (0.1%), sand (89.0%), and silt and clay (10.9%). The water content of the sea sand was adjusted to 12.6% (w/w) for the study. Different combinations of the following treatments were applied to the sand in biometer flasks: the concentration of oil (3% or 6%), the concentration of a mixture of three oil-degrading microorganisms (Corynebacterium sp. IC-10, Sphingomonas sp. KH3-2 and Yarrowia sp. 180, 1x10(6) or 1x10(8) cells g-1 sand), the concentration of the surfactant Tween 80 (1 or 10 times the critical micelle concentration), and the addition of SRIF in a C:N:P ratio of 100:10:3. Three biometer flasks per combination of experimental conditions were incubated, and the performance of each treatment was examined by monitoring CO2 evolution, microbial activity, and oil degradation rate. The results suggest that the addition of inorganic nutrients accelerated the rate of CO2 evolution by a factor of 10. The application of oil-degrading microorganisms in a concentration greater than that of the indigenous population clearly increased biodegradation efficiency. The application of surfactant slightly enhanced the oil degradation rate in the contaminated sand treated with the higher concentration of oil-degrading microorganisms. The initial CO2 evolution rate was shown to efficiently evaluate the treatability test by providing significant data within a short period, which is critical for the rapid determination of the appropriate bioremediation approach. The measurements of microbial activity and crude oil degradation also confirmed the validity of the CO2 evolution rate as an appropriate criterion.


Assuntos
Dióxido de Carbono/análise , Corynebacterium/metabolismo , Petróleo/metabolismo , Sphingomonas/metabolismo , Yarrowia/metabolismo , Biodegradação Ambiental , Dióxido de Carbono/metabolismo , Fertilizantes , Dióxido de Silício
17.
Asian Spine J ; 9(2): 162-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25901225

RESUMO

STUDY DESIGN: Case control study. PURPOSE: To examine the effect of spino-pelvic sagittal parameters and back muscles on osteoporotic vertebral fracture. OVERVIEW OF LITERATURE: Low bone mass is not the only important component of the risk on osteoporotic vertebral fracture; many other risk factors also contribute to skeletal fragility. METHODS: Seventy-two patients who had a lateral radiograph of the whole spine, magnetic resonance imaging of the lumbar spine, and bone densitometry, were enrolled. The spino-pelvic sagittal parameters (pelvic incidence, pelvic tilt [PT], sacral slope, thoracic kyphosis, lumbar lordosis), age, lumbar bone mineral density, and amount of back muscle around the lumbar spine were analyzed. RESULTS: There was higher sagittal imbalance of the spine in the vertebral fracture group (p=0.011). In spinopelvic parameters, the average of PT was 22.13° in vertebral fracture group and 13.70° in the non-fracture group (p=0.002). The amount of lower back extensor muscle in the vertebral fracture group was 2,170 mm(2), which was lower than the non-fracture group (3,040 mm(2), p=0.001). Multiple logistic regression analysis for the risk of osteoporotic vertebral fracture was significant in lumbar bone mineral density (odds ratio [OR], 0.313; 95% confidence interval [CI], 0.139-0.706, p=0.005) and the muscle ratio of extensor back muscle (OR, 0.902; 95% CI, 0.826-0.984; p=0.020). CONCLUSIONS: These results suggest that osteoporotic vertebral fracture could be developed easily by weakness of extensor back muscle in sagittal imbalance of the spine with high pelvic tilt.

18.
Asian Spine J ; 9(5): 683-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26435784

RESUMO

STUDY DESIGN: A prospective sonographic study. PURPOSE: To verify the effectiveness of simultaneous application of two landmarks, Doppler image of the vertebral artery and shape of the transverse tubercle of the seventh cervical (C7) vertebra. OVERVIEW OF LITERATURE: Counting upwards from the C7 vertebra which only has a posterior tubercle of the transverse process is a commonly used method for ultrasound-guided cervical nerve root block. However, each transverse process has a different shape. METHODS: Sonograms of 20 volunteers were examined. At first, we identified the C7 transverse process based on the presence of the vertebral artery without the anterior tubercle. The C5 and C6 transverse processes were identified based on the presence of anterior tubercle without the vertebral artery. Subsequently, we placed needles on the C5, C6, and C7 transverse processes and the location and direction of needles were confirmed by fluoroscopy. RESULTS: In the 120 segments, 93.3% of needles were placed correctly as desired; 97.5% of needles were placed on the 5C transverse process; 97.5% of needles were placed on the C6 transverse process; and 85.0% of needles were placed on the C7 transverse process, respectively. Both sides showed the same accuracy of 93.3%. CONCLUSIONS: Simultaneous application of Doppler image of the vertebral artery and shape of the C7 transverse tubercle showed 93.3% accuracy in identifying the target cervical level. Therefore, Doppler image of the vertebral artery can be considered to be a useful landmark for ultrasound-guided cervical nerve root block.

19.
Toxicol In Vitro ; 28(8): 1402-12, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25086211

RESUMO

Magnetic nanoparticles have been widely used in a broad range of disciplines owing to their unique properties. However, many unexpected risks have been reported in their use. In this study, we investigated the uptake process and toxic mechanism of magnetic iron oxide nanoparticles (M-FeNPs) using RAW264.7 cells, a murine peritoneal macrophage cell line. M-FeNPs markedly enhanced the mobility of cells. At 24h after exposure, M-FeNPs were located freely in the cytosol or within autolysosomes containing various organelles, especially the endoplasmic reticulum (ER). Cell viability decreased in a dose-dependent manner in conjunction with the arrest in S phase. ATP production also rapidly decreased together with mitochondrial damage, the number of cells that generate ROS increased, and the secretions of pro-inflammatory cytokines enhanced. The levels of oxidative stress- and ER stress-related genes were up-regulated, whereas the levels of transcription-related genes were down-regulated. Additionally, the levels of autophagy- and ER stress-related proteins increased, and the number of apoptotic cells increased with time. We also investigated the function of the autolysosome in the cellular response after exposure of M-FeNPs. When cells were exposed to M-FeNPs for 24h with BaFA1 pretreatment, the plasma membrane disintegrated, cytosolic components disappeared, and the number of apoptotic cells significantly increased. Taken together, these results show that M-FeNPs induce autophagy preceding apoptosis through mitochondrial dysfunction and ER stress in RAW264.7 cells. Furthermore, blocking of autolysosome formation may accelerate apoptotic cell death and ER stress.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Compostos Férricos/toxicidade , Nanopartículas Metálicas/toxicidade , Mitocôndrias/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Expressão Gênica/efeitos dos fármacos , Lisossomos/fisiologia , Camundongos , Espécies Reativas de Oxigênio/metabolismo
20.
Asian Spine J ; 8(6): 729-34, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25558314

RESUMO

STUDY DESIGN: Retrospective study. PURPOSE: To determine the prevalence of high risk patient with osteopenia requiring pharmacologic treatment and investigate the difference of 10-year fracture probability whether bone mineral density (BMD) include or not in Korean FRAX model. OVERVIEW OF LITERATURE: Many people with the fracture have osteopenia rather than osteoporosis, and BMD alone could be considered as a chance to prevent fracture. METHODS: Three hundred sixty-nine patients who was diagnosed as osteopenia were divided into two groups according to age (group 1, under 65 years; group 2, over 65 years), and 10-year fracture probabilities were calculated by FRAX algorithm with and without femur neck T-score. RESULTS: The high risk patients of the fracture who had above 3% of 10-year hip fracture probability were 15 cases in group 1 and 121 cases in group 2. In 193 patients of group 1, the mean 10-year fracture probability with BMD was significantly higher than the results without BMD (hip fracture: p=0.04, major osteoporotic fracture: p=0.01). Unlike the results of the group 1, the mean 10-year fracture probability without BMD was significantly higher than the results with BMD in 176 patients of group 2 (hip fracture: p=0.01, major osteoporotic fracture: p=0.01). CONCLUSIONS: Total of 136 cases (36.8%) as a high risk of the fracture with osteopenia could be overlooked treatment eligibility in Korean. The Korean FRAX model without BMD could be effective in predicting fracture risk especially in the individuals who were over 65 years.

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