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Objective: Klebsiella pneumoniae liver abscess (KPLA) is an invasive infectious disease with a considerable prevalence and complications. This study aimed to determine the predicted value of aspartate aminotransferase-to-platelet ratio index (APRI) and fibrosis-4 index (FIB-4) for positive blood cultures and sepsis in patients with KPLA. Methods: We evaluated 248 consecutive participants diagnosed with KPLA. Demographic characteristics, clinical features, and laboratory test results of the participants were recorded. Multivariate logistic regression analysis was performed to identify the risk factors. Receiver operating characteristic (ROC) analyses were conducted to evaluate the discriminatory ability of APRI and FIB-4. Results: 30.2% (75 of 248) KPLA patients presented with positive blood cultures, and 70 (28.2%) developed sepsis. Among the positive blood culture and sepsis groups, the APRI and FIB-4 showed statistically significant increases. Multivariate analysis showed that APRI (odds ratio [OR] = 1.190, 95% confidence interval [CI] 1.051-1.347, p = 0.006) and FIB-4 (OR = 1.110, 95% CI 1.046-1.179, p = 0.001) were independent prognostic factors for positive blood cultures. Both APRI (OR = 1.505, 95% CI 1.149-1.988, p = 0.004) and FIB-4 (OR = 1.187, 95% CI 1.054-1.336, p = 0.005) were independent risk factors for sepsis. The area under the ROC curve (AUC) of APRI and FIB-4 for predicting positive blood cultures of KPLA was 0.783 and 0.766, respectively. APRI had an AUC of 0.801, with a sensitivity and specificity of 71.4% and 81.5%, respectively, for predicting sepsis in patients with KPLA, and the prediction performance of APRI was better than that of FIB-4 (AUC = 0.798). Conclusion: In our study, APRI and FIB-4 are effective methods for predicting KPLA patients with positive blood cultures and sepsis.
Subject(s)
Amenorrhea , Antiviral Agents , Influenza A virus , Influenza, Human , Oseltamivir , Humans , Female , Oseltamivir/adverse effects , Oseltamivir/therapeutic use , Amenorrhea/chemically induced , Antiviral Agents/adverse effects , Antiviral Agents/therapeutic use , Influenza, Human/drug therapy , AdultABSTRACT
What we believe to be a novel integrated circular polarization dynamic converter (CPDC) is proposed based on the four-layer mirror symmetry structure. By designing the twisted structure and rearranging the orientation direction of liquid crystal molecules for each layer, the application wavelength range could be broadened. For the viewing angle expansion, negative birefringent films are selected to compensate for the retardation deviation under oblique incidence. Finally, the particle swarm algorithm is used to optimize the whole configuration, and the polarization conversion efficiency calculated by the finite element method (FEM) can achieve 90% in the wavelength range from 320â nm to 800â nm at an ultrawide view of 160°. Compared with traditionally active liquid crystal waveplates, the design has potential advantages in both wavelength and field of view (FOV) and provides the possibility for the integrated and flimsy fabrication of devices.
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Objective: Severe pneumonia is a common infectious disease with high morbidity and mortality. Early etiological diagnosis is crucial for improving the prognosis. The aim of this study is to evaluate the clinical value of sampling time of mNGS in patients with severe pneumonia. Methods: This retrospective study enrolled 105 patients with severe pneumonia. mNGS was performed on bronchoalveolar lavage fluid (BALF). Patients were divided into the sampling time ≤ 72h vs sampling time >72h groups and survivors vs non-survivors groups according to their sampling time and prognosis. Clinical characteristics, the adjustment of antibiotics and clinical prognostic value were evaluated. Results: Our study showed that, early sampling of mNGS can significantly shorten the mechanical ventilation time (p = 0.007) and hospitalization time (p = 0.004). In the non-survivors group, CURB-65, SOFA, and APACHE II scores were higher. Age (OR: 1.051, 95% CI: 1.004-1.100, p = 0.034), chronic respiratory diseases (OR: 4.639, 95% CI: 1.260-17.082, p = 0.021), immunosuppression (OR: 5.008, 95% CI: 1.617-15.510, p = 0.005) and SOFA score on the day of mNGS sampling (OR: 1.492, 95% CI: 1.212-1.837, p < 0.001) were independent risk factors of in-hospital mortality. The most common pathogens were Klebsiella pneumoniae and Human gammaherpesvirus 4. The proportion of appropriate and targeted antibiotics adjusted was significantly higher than that in the sampling time > 72h group, and the proportion of antifungal and antiviral agents adjusted was lower. In the early sampling group, it was significantly decreased in the CRP, PCT level and NEU% at discharge. Conclusion: This study demonstrated that early sampling of mNGS could shorten the time of mechanical ventilation and hospitalization of patients with severe pneumonia. Patients with higher SOFA score on the day of sampling had a poorer prognosis. It emphasizes that early sampling of mNGS has a positive value.
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Gray scale consistency in pixels was extremely important for electrowetting displays (EWDs). However, traditional electrowetting display driving waveforms could not obtain a pixel aperture ratio consistency, which led to the occurrence of gray inconsistency even if it was the same driving waveform. In addition, the oil backflow caused by charge trapping could not be sustained. Therefore, a multi-direct current (DC) overdriving waveform for gray scale consistency was proposed in this paper, which could effectively improve the performance of EWDs. The driving waveform was divided into a start-up driving phase and a stable driving phase. The stable driving phase was composed of a square wave with a duty cycle of 79% and a frequency of 43 Hz. Subsequently, an overdriving pulse was also introduced in the stable driving phase. The multi-DC driving waveform for gray scale consistency was applied to a thin film transistor-electrowetting display (TFT-EWD). The average difference between increasing driving voltage and decreasing driving voltage was only 2.79%. The proposed driving waveform has an aperture ratio of 3.7 times at low voltages compared to DC driving.
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Purpose: We analyzed the clinical concordance of mNGS test results from blood samples and improved the clinical efficiency of mNGS in the diagnosis of suspected sepsis pathogens. Patients and Methods: In this study, 99 samples of suspected blood flow infection were included for plasma mNGS, and the correlation between mNGS results and blood culture results, serum inflammatory indices, clinical symptoms and antibiotic treatment was analyzed, as well as the comparison with the detection rate of BALF pathogens, as well as the classification of different pathogens in the mNGS results were analyzed. Results: The mNGS pathogen detection rate was higher than that of traditional blood culture (83.02% vs 35.82%). The rate of the mNGS results being consistent with the clinical diagnosis was also higher than that of traditional blood culture (58.49% vs 20.75%). This study shows that bacteria and fungi are the main pathogens in sepsis, and viral sepsis is very rare. In this study, 32% of sepsis patients were secondary to pneumonia. Compared with the pathogen detection rate using alveolar lavage fluid, the detection rate from plasma mNGS was 62.5%. Samples were also easy to sample, noninvasive, and more convenient for clinical application. Conclusion: This study shows that compared with blood culture, the detection rate of mNGS pathogen that meets the diagnosis of sepsis is higher. We need a combination of multiple indicators to monitor the early diagnosis and treatment of sepsis.
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A high-speed circular polarization converter (CPC) with a wide field of view (FOV) and wavelength range is designed and fabricated in this paper. The multi-waveplate combined structure is applied to constitute the basic configuration of the CPC for broadening the wavelength range. An electrically suppressed helix ferroelectric liquid crystal (ESHFLC) material with fast response is used as a medium for dynamic polarization operation. The compensation films are used to expand the FOV by attaching to the configuration. The simulation results demonstrate that the optimized CPC structure can achieve over 97% orthogonal circular polarization conversion efficiency in 300â nm bandwidth at a 90° viewing cone for both working states. Finally, we have experiments and the results show well consistency with the theoretical results.
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As a representative of the new reflective display technology, electrowetting display (EWD) technology can be used as a video playback display device due to its fast response characteristics. Direct current (DC) driving brings excellent reflectivity, but static images cannot be displayed continually due to charge trapping, and it can cause afterimages when playing a dynamic video due to contact angle hysteresis. Alternating current (AC) driving brings a good dynamic video refresh ability to EWDs, but that can cause flickers. In this paper, a dynamic adaptive display model based on thin film transistor-electrowetting display (TFT-EWD) was proposed. According to the displayed image content, the TFT-EWD display driver was dynamically adjusted by AC and DC driving models. A DC hybrid driving model was suitable for static image display, which could effectively suppress oil backflow and achieve static image display while ensuring high reflectivity. A source data non-polarized model (SNPM) is an AC driving model which was suitable for dynamic video display and was proposed at the same time. Compared with DC driving, it could obtain smooth display performance with a loss of about 10 absorbance units (A.U.) of reflective luminance, which could solve the flicker problem. With the DC hybrid driving model, the ability to continuously display static images could be obtained with a loss of 2 (A.U.) of luminance. Under the AC driving in SNPM, the reflected luminance was as high as 67 A.U., which was 8 A.U. higher than the source data polarized model (SPM), and it was closer to the reflected luminance under DC driving.
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Entrepreneurship education activities in colleges and universities play an important role in improving students' innovation ability. Therefore, this paper has important practical value to evaluate the innovation and entrepreneurship ability of college students. At present, most studies use qualitative research methods, which is inefficient. Even if quantitative analysis is adopted, it is mostly linear analysis, which is inconsistent with the actual situation. In order to improve the application level of genetic algorithm to the innovation and entrepreneurship ability of universities based on BP neural network, this paper studies the evaluation model of innovation and entrepreneurship ability of universities. Based on the simple analysis of the current situation of university innovation and entrepreneurship ability evaluation and the application progress of BP neural network, combined with the actual situation of university innovation and entrepreneurship, this paper constructs the innovation and entrepreneurship evaluation index, uses BP neural network to build the evaluation model, and uses genetic algorithm to optimize and improve the shortcomings of BP neural network. Then, the experimental analysis and application design are carried out. The results show that the improved algorithm is basically consistent with the predicted value, small error, and fast convergence. When it is used in the evaluation of innovation and entrepreneurship ability, quantitative analysis results can be obtained, which provides a certain reference for the development of enterprises.
Subject(s)
Entrepreneurship , Students , Humans , Neural Networks, Computer , UniversitiesABSTRACT
OBJECTIVE: The purpose of the current study was to evaluate the association between C-reactive protein-to-platelet ratio (CPR), neutrophil-to-lymphocyte*platelet ratio (NLPR) and fibrinogen-to-platelet ratio (FPR) and the prognoses of pyogenic liver abscess (PLA) patients. METHODS: A cohort of 372 patients with confirmed PLA were enrolled in this retrospective study between 2015 and 2021. Laboratory data were collected on admission within 24 h. The demographic characteristics and clinical features were recorded. Risk factors for outcomes of PLA patients were determined via multivariate logistic regression analyses, and optimal cut-off values were estimated by using the receiver operating characteristic (ROC) curve analysis. RESULTS: Out of 372 patients, 57.8% were men, 80 (21.5%) developed sepsis, and 33 (8.9%) developed septic shock. The levels of CPR, NLPR and FPR were significantly increased in the development of sepsis, and prolonged hospital stays in PLA patients. The multivariate logistic regression analysis indicated that the CPR (OR: 2.262, 95% CI: 1.586-3.226, p < 0.001), NLPR (OR: 1.118, 95% CI: 1.070-1.167, p < 0.001) and FPR (OR: 1.197, 95% CI: 1.079-1.329, p = 0.001) were independent risks of PLA patients with sepsis, and NLPR (OR: 1.019, 95% CI: 1.004-1.046, p = 0.019) was shown to be an independent predictor of prolonged hospital stays. The ROC curve results showed that the three biomarkers had different predictive values, and CPR proved to work best, with a ROC value of 0.851 (95% CI: 0.807-0.896, p < 0.001) for sepsis. CONCLUSION: Higher levels of CPR, NLPR and FPR were associated with a higher risk of poor outcomes. Moreover, a high CPR level performed best when predicting the clinical outcome in PLA patients.
Subject(s)
Liver Abscess, Pyogenic , Sepsis , Female , Humans , Liver Abscess, Pyogenic/diagnosis , Male , Platelet Count , Prognosis , ROC Curve , Retrospective StudiesABSTRACT
Objective: Metagenomic next-generation sequencing (mNGS) technology has the potential to detect a wide range of pathogenic microorganisms. However, reports on the diagnostic value and clinical significance of different platforms of mNGS for patients with lower respiratory tract infections (LRTIs) remain scarce. Methods: A total of 306 patients with suspected LRTIs were enrolled from January 2019 to December 2021. The diagnostic performance of conventional methods and mNGS on bronchoalveolar lavage fluid (BALF) were compared. BALF mNGS was performed using a commercial and an in-house laboratory. The diagnostic value and the clinical implications of mNGS for LRTIs were analyzed for the different platforms. Results: The positive rate of mNGS in the in-house group was higher than that in the commercial group (85.26% vs. 70.67%, p < 0.001). mNGS significantly increased the pathogen detection rate compared with conventional methods [from 70.67% vs. 22.67% (p < 0.001) to 85.26% vs. 30.77% (p < 0.001)]. The pathogens detected using mNGS included bacteria, fungi, viruses, and atypical pathogens. The in-house platform performed well on a wider spectrum of microbial distribution. Furthermore, it showed an advantage in detecting mixed pathogens in immunocompromised patients. Among the mNGS positive cases, 34 (32.0%) cases had their antibiotics adjusted in the commercial group, while 51 (38.3%) cases had a change of treatment in the in-house group. Moreover, the turnaround time of mNGS and the time from mNGS to discharge in the in-house group were significantly shorter than those in the commercial group. Conclusion: In-house mNGS had a higher detection rate and can show a wider spectrum of pathogens, with potential benefits for the clinic by shortening the turnaround time and hospitalization, and it may be more suitable for clinical microbiology laboratories.
Subject(s)
Clinical Relevance , Respiratory Tract Infections , Humans , Bronchoalveolar Lavage Fluid , High-Throughput Nucleotide Sequencing , Anti-Bacterial Agents , Metagenomics , Respiratory Tract Infections/diagnosis , Sensitivity and SpecificityABSTRACT
BACKGROUND: Klebsiella pneumoniae is a primary pathogen of pyogenic liver abscess (PLA). However, little data are available on combination with sepsis. In this study, we aimed to evaluate the clinical characteristics and prognostic differences of PLA patients with sepsis. METHODS: This retrospective cohort study was conducted to investigate 135 patients with confirmed Klebsiella pneumoniae-caused liver abscesses (KPLA) from a tertiary teaching hospital, from 2013 to 2019. The patients were divided into two groups, KPLA with sepsis and KPLA without sepsis. The demographic characteristics, clinical features as well as laboratory and microbiologic findings were analyzed. RESULTS: A total of 135 patients with KPLA were analyzed. The mean age of patients was 60.9 ± 12.7 years, and the percentage of men was 59.3%. Among them, 37/135 (27.4%) of patients had sepsis and the mortality rate was 1.5%. The most common symptom was fever (91.1%). KPLA patients with sepsis had a significantly higher proportion of frailty, diarrhea, fatty liver, chronic renal insufficiency, and hepatic dysfunction compared to KPLA patients without sepsis (p < 0.05). Antibiotic therapy and percutaneous drainage were most frequently therapeutic strategy. Furthermore, the incidences of sepsis shock and acute respiratory distress syndrome were higher in the sepsis group compared to the non-sepsis group. As for metastatic infections, the lung was the most common site. In addition, KPLA patients with sepsis showed respiratory symptoms in 11 patients, endophthalmitis in 4 patients, and meningitis in 1 patient. CONCLUSION: Our findings emphasize that KPLA patients combined with or without sepsis have different clinical features, but KPLA patients with sepsis have higher rates of complications and metastatic infections. Taken together, further surveillance and control of septic spread is essential for KPLA patients.
Subject(s)
Klebsiella Infections/complications , Klebsiella pneumoniae , Liver Abscess, Pyogenic/complications , Sepsis/etiology , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Retrospective StudiesABSTRACT
BACKGROUND AND OBJECTIVES: Cerebral microbleeds (CMBs) are cerebral small vascular diseases and are often used to diagnose symptoms such as stroke and dementia. Manual detection of cerebral microbleeds is a time-consuming and error-prone task, so the application of microbleed detection algorithms based on deep learning is of great significance. This study presents the feature enhancement technology applying to improve the performances of detecting CMBs. The primary purpose of the feature enhancement is emphasizing the meaningful features, leading deep learning network easier and correctly to optimize. METHOD: In this study, we applied feature enhancement in detecting CMBs from brain MRI images. Feature enhancement enhanced specific intervals and suppressed the useless intervals of the feature map. This method was applied in SSD-512 and SSD-300 algorithm, using VGG architecture pre-trained in the ImageNet dataset. RESULTS: The proposed method was applied in SSD-512. Moreover, the model was trained and tested on the sequence of SWAN images of brain MRI images. The results of the experiment demonstrate that our method effectively improves the detection performance of the SSD network in detecting CMBs. We train SSD-512 120000 iterations and test results on the test datasets, by applying the feature enhancement layer, improving the precision with 3.3% and the mAP of 2.3%. In the same way, we trained SSD-300, improving the mAP of 2.0%. 2.8% and 7.4% precision are improved by applying feature enhancement layer In ResNet-34 and MobileNet. CONCLUSIONS: The proposed method achieved more effective performance, demonstrated that feature enhancement can be a helpful algorithm to enhance the deep learning model.
Subject(s)
Deep Learning , Algorithms , Cerebral Hemorrhage/diagnostic imaging , Humans , Magnetic Resonance Imaging , NeuroimagingABSTRACT
Progranulin (PGRN) is a secreted protein that can regulate cell cycle progression, cell motility, and tumorigenesis. The PGRN expression in hematological malignancies is limited to multiple myeloma, but its expression and survival prognostic role in acute myeloid leukemia (AML) is still controversial.To evaluate the PGRN expression and estimate its survival prognostic role in AML patients.In this study, all patients were divided into three groups, which included 38 newly diagnosed adult AML patients, 33 complete remissions (CR-AML) patients, and 60 healthy control (HC) patients. The endpoints were relapse-free survival (RFS) and overall survival (OS). We investigated plasma PGRN levels by using enzyme-linked immunosorbent assay.Plasma PGRN levels in AML patients were higher than that in CR-AML and HC groups. After two chemo cycles, 16 patients had complete remission (CR). The level of plasma PGRN in non-CR patients compared to CR patients was obviously different (median 44.19 vs 21.10âng/mL) (Pâ=â.025). In non-M3 (French-American-British classification) patients, 70% (21/30) patients relapsed in 1 year and 80% (24/80) patients died in the observed time. Using the value (median 19.95) as a "cut-off" value, we have divided non-M3 patients into low- and high-PGRN expression groups. High-PGRN expression patients had a poorer RFS with a median of 5.4 months (95% CI 3.7-7.1) and low-PGRN expression patients had a good RFS with a median of 8.9 months (95% CI 6.3-11.5; Pâ=â.027). In the survival analyses, high-PGRN expression of AML patients had shorter OS than low-PGRN expression of AML patients (6.2 vs 20.5 months, Pâ=â.008).PGRN is overexpressed in AML, which is a convenient and independent prognostic marker that is measured easily in AML patients.
Subject(s)
Leukemia, Myeloid, Acute/blood , Leukemia, Myeloid, Acute/mortality , Progranulins/blood , Adolescent , Adult , Aged , Biomarkers, Tumor/blood , Case-Control Studies , Female , Humans , Induction Chemotherapy/mortality , Leukemia, Myeloid, Acute/drug therapy , Male , Middle Aged , Prognosis , Survival Analysis , Young AdultABSTRACT
Adenoid cystic carcinoma (ACC) is an uncommon salivary gland malignancy with a poor long-term prognosis. Clinical reports show the high rates of local recurrences and distant metastases. This study aimed to investigate the expression of MIF, Beclin1, and light-chain 3 (LC3) in salivary adenoid cystic carcinoma (SACC).Tissue specimens were obtained from 48 salivary glands adenoid cystic carcinoma (SACC) patients and 15 oral squamous cell carcinoma (OSCC) patients. Immunohistochemical staining was performed to estimate the level of LC3, Beclin1, and MIF. All SACC patients were followed up. The Kaplan-Meier method was used to compare the prognosis of patients after treatment.The 3-year, 5 year-, and 10 year-survival rates of the SACC patients were 83.9%, 69.9%, and 46.6%, respectively. MIF, LC3, and Beclin1 in SACC were all obviously over-expressed. MIF showed an increased tendency in cases with advanced TNM stages, and at the same time, there was an inversely proportional relationship between MIF and LC3, Beclin1.The long-term survival of SACC patients is poor. MIF might be a risk factor for SACC patients, whereas, LC3 and Beclin1 might be an effective strategy for treatment of SACC.
Subject(s)
Beclin-1/metabolism , Carcinoma, Adenoid Cystic/metabolism , Intramolecular Oxidoreductases/metabolism , Macrophage Migration-Inhibitory Factors/metabolism , Microtubule-Associated Proteins/metabolism , Pathology, Molecular/methods , Salivary Gland Neoplasms/metabolism , Adult , Aged , Carcinoma, Adenoid Cystic/mortality , Carcinoma, Adenoid Cystic/pathology , Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/mortality , Carcinoma, Squamous Cell/pathology , Female , Humans , Male , Middle Aged , Mouth Neoplasms/pathology , Neoplasm Staging/methods , Prognosis , Salivary Gland Neoplasms/mortality , Salivary Gland Neoplasms/pathology , Salivary Glands/pathology , Survival RateABSTRACT
Drug resistance represents a major obstacle to improving the overall response and survival of cancer patients. Taxol is one of the most commonly used chemotherapy agents in breast cancer. As with many cancer therapeutic agents, resistance remains a significant problem when using Taxol to treat malignancies. In this study, estrogen receptor positive breast cancer cells MCF-7 were induced Taxol resistance. And Tanshinone IIA combined with Taxol was chosen to treat it. The drugs combination showed additive effect in most drug concentrations. Drug resistance cancer cells showed a higher microtubule associated protein (Tau) expression, which was considered as one of the reasons for Taxol resistance. Tanshinone IIA inhibited the expression of Tau in MCF-7 cells and resulted in higher sensibility of Taxol. Moreover, Tanshinone IIA also showed cytotoxicity to MCF-7, which might be related to its estrogenicity effect. In conclusion, the combination of Tanshinone IIA and Taxol showed higher cytotoxicity to Taxol resistant MCF-7 cells, which might be related to the inhibition of Tau.
Subject(s)
Abietanes/therapeutic use , Antineoplastic Agents, Phytogenic/therapeutic use , Breast Neoplasms/drug therapy , Paclitaxel/therapeutic use , Abietanes/pharmacology , Antineoplastic Agents, Phytogenic/pharmacology , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Cell Line, Tumor , Drug Resistance, Neoplasm/drug effects , Female , Humans , MCF-7 Cells , Paclitaxel/pharmacologyABSTRACT
Calcium alginate microbeads have been widely used in tissue engineering application, due to their excellent biocompatibility, biodegradability, enhanced mechanical strength and toughness. Bone powder containing abundant hydroxylapatite, type I collagen and growth factors such as BMP2 and BMP4, possesses good osteoinductive activity. Herein, a hybrid calcium alginate/bone powder microbead was therefore prepared. Afterwards, different seeding density of adipose-derived stem cells (ADSCs) in these hybrid microbeads was discussed systematically for further in vitro expansion. Optimised microbeads suitable for in vitro expansion and differentiation of ADSCs were prepared using the droplet method under overall considering suitable concentrations of calcium alginate and calcium chloride as well as the density of bone powder through an orthogonal experiment. The results showed that the concentration of sodium alginate had the most influence on inside mass transfer and mechanical strength of the hybrid microbeads, secondly the calcium chloride, then the density of bone powder. The hybrid microbeads could be optimally performed while the concentrations of sodium alginate and calcium chloride were 2.5% and 4.5%, as well as 5.0 mg/mL bone powder, respectively. Live/Dead assay showed that the expanded ADSCs differentiated well with an initial embedding density of 5 × 10(6) cells/mL.
Subject(s)
Adipose Tissue/metabolism , Alginates , Bone and Bones/chemistry , Microspheres , Stem Cells/metabolism , Adipose Tissue/cytology , Alginates/chemistry , Alginates/pharmacology , Calcium Chloride/chemistry , Calcium Chloride/pharmacology , Female , Glucuronic Acid/chemistry , Glucuronic Acid/pharmacology , Hexuronic Acids/chemistry , Hexuronic Acids/pharmacology , Humans , Male , Powders , Stem Cells/cytologyABSTRACT
Neural stem cells (NSCs) forming neurospheres in a conventional culture tend to develop necrotic/apoptotic centers due to mass transport limitations. In this study, the internal pore structure of calcium-alginate/gelatin (CAG) microbeads was tuned and controlled to provide a suitable three-dimensional environment supporting NSC proliferation. Direct impact of three-dimensional space availability was quantified by oxygen consumption rates of NSCs and cells were cultured in three different methods: neurospheres, single cell suspension of NSCs, and encapsulated NSCs in microbeads. Our results showed that encapsulated NSCs in CAG microbeads maintained higher cell viability than in conventional culture. In addition, NSCs encapsulated in CAG microbeads preserved their original stemness and continued to express nestin, CNPase, GFAP and ß-tubulin-III post-encapsulation. Oxygen consumption rates of encapsulated NSCs in CAG microbeads were the lowest as compared to the other two culture methods. The optimal cell density supporting high cell proliferation in CAG microbeads was found to be 1.5×10(5)cells/mL. The glucose consumption curve suggests that encapsulated NSCs in microbeads had a slower growth profile. This study presents an alternative method in hybrid microbead preparation to generate a highly favorable three-dimensional cell carrier for NSCs and was successfully applied for its effective in vitro expansion.
Subject(s)
Alginates/chemistry , Calcium/chemistry , Gelatin/chemistry , Microspheres , Neural Stem Cells/cytology , Animals , Cell Culture Techniques , Cell Survival , Cells, Cultured , Glucuronic Acid/chemistry , Hexuronic Acids/chemistry , Mice , Neural Stem Cells/metabolism , Oxygen ConsumptionABSTRACT
Bacillus mucilaginosus and Bacillus edaphicus were reclassified based on their 16S rRNA and gyrB gene sequences, DNA-DNA hybridization, fatty acid methyl esters and other taxonomic characteristics. Phylogenetic analysis based on 16S rRNA and gyrB gene sequences indicated that strains of B. mucilaginosus and B. edaphicus were members of the genus Paenibacillus, with over 90.4 % and 70.3 % sequence similarity, respectively. Their DNA G+C contents were 54.5-56.8 mol%. The DNA-DNA relatedness values of B. edaphicus VKPM B-7517(T) with B. mucilaginosus KNP414 and B. mucilaginosus CGMCC 1.236 were 89.2 % and 88.7 %, respectively. The major isoprenoid quinone of B. mucilaginosus and B. edaphicus was MK-7 (94.1-95.7 %). The peptidoglycan type was A1gamma (meso-diaminopimelic acid) and the major polar lipids were phosphatidylglycerol and diphosphatidylglycerol. The major fatty acids were anteiso-C(15 : 0), C(16 : 1)omega11c and C(16 : 0). Phenotypic features and fatty acid profiles supported the similarity of B. mucilaginosus and B. edaphicus to Paenibacillus validus CCTCC 95016(T) and confirmed their relationship with members of the genus Paenibacillus. Therefore, it is proposed that Bacillus mucilaginosus and Bacillus edaphicus be transferred to the genus Paenibacillus as Paenibacillus mucilaginosus comb. nov. (type strain HSCC 1605(T)=VKPM B-7519(T)=VKM B-1480D(T)=CIP 105815(T)=KCTC 3870(T)) and Paenibacillus edaphicus comb. nov. (type strain VKPM B-7517(T)=DSM 12974(T)=CIP 105814(T)), respectively.
Subject(s)
Bacillus/classification , Bacillus/isolation & purification , Bacillus/genetics , Bacillus/metabolism , Bacterial Proteins/genetics , Bacterial Typing Techniques , Base Composition , DNA Gyrase/genetics , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , Fatty Acids/metabolism , Molecular Sequence Data , Phylogeny , RNA, Ribosomal, 16S/geneticsABSTRACT
Pinellia ternata, a traditional Chinese herb that has been used in China for over 1000 years, is susceptible to a soft rot disease, which may cause major loss of yield. The use of bacteria as potential antagonists against Pectobacterium carotovorum SXR1, the causal agent of the disease on P. ternata, was evaluated. Altogether, 1107 candidate bacteria were isolated from the rhizosphere and surface-sterilized plants of P. ternata. In Petri dish tests, 55 isolates inhibited the growth of strain SXR1, and 21 of these reduced the disease development on P. ternata slices by over 50%. Four selected antagonists significantly reduced the disease incidence on tissue culture seedlings, and also prevented the disease on the transplants. Agonist P-Y2-2 yielded a good prevention level of 81.9%. The four antagonists rapidly colonized the tissue culture seedlings and transplants, whereas greater populations of the antagonists (10(7)-10(9) CFU g(-1) fresh tissues) were observed in the seedlings and in the preinoculated transplants than in those inoculated during transplanting. The use of pathogen-free tissue culture seedlings pre-inoculated with antagonist may provide a strategy for production of P. ternata plantlets resistant to soft rot disease. This is the first report on the efficacy of biocontrol agents against pathogens on P. ternata.