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1.
Phys Chem Chem Phys ; 26(5): 3869-3879, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38226609

RESUMO

Rare-earth-doped silica-based composite glasses (Re-SCGs) are widely used as high-quality laser gain media in defense, aerospace, energy, power, and medical applications. The variable regional chemical environments of Re-SCGs can induce new photoluminescence properties of rare-earth ions but can cause the selective aggregation of rare-earth ions, limiting the application of Re-SCGs in the field of high-power lasers. Here, topological engineering is proposed to adjust the degree of cross-linking of phase-separation network chains in Re-SCGs. A combination of experimental and theoretical characterization techniques suggested that the selective aggregation of rare-earth ions originates from the formation of phase-separated structures in glasses. The decomposition of nanoscale phase separation structures to the sub-nanometer scale, enabled by incorporating Al3+ ions, not only maintains the high luminescence efficiency of rare earth ions but also increases light transmittance and reduces light scattering. Furthermore, our investigation encompassed the exploration of the inhibitory mechanism of Al3+ ions on phase-separation structures, as well as their influence on the spectral characteristics of Re-SCGs. This work provides a new design concept for composite glass materials doped with rare-earth ions and could broaden their application in the field of high-power lasers.

2.
Ann Gen Psychiatry ; 22(1): 46, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37957751

RESUMO

OBJECTIVE: To evaluate the clinical efficacy and safety of Agomelatine in improving symptoms in patients with major depressive disorder (MDD), providing more scientific evidence for the treatment of depression, and offering more effective therapeutic options for patients. METHODS: A total of 180 MDD patients in acute phase from 10 psychiatric hospitals of Grade three in Zhejiang Province were enrolled in this 12-week study with the competitive and consecutive pattern, and they were randomized into two different groups treated with flexible-dosage antidepressants of selective serotonin reuptake inhibitors (SSRI) or agomelatine, respectively. The subjects were evaluated with psychological scales of HAMD-17, HAMA, SHAPS for anhedonia, MFI-20 for fatigue, PQSI for sleep quality and MEQ for disturbances in chronobiologic rhythms at baseline, 2, 4, 8 and 12-weekend points, and TESS was used for side-effect. The results were analyzed with repeated measurement analysis of variance. RESULTS: The two groups each had 90 participants, and there were no significant differences at baseline. The scores of various assessment scales showed statistically significant time main effects during the visits (P < 0.01). The Agomelatine group demonstrated faster efficacy within 2 weeks, with better improvement in SHAPS, MEQ, and PSQI compared to the SSRIs group. However, the remission rate at 12 weeks was lower in the Agomelatine group than in the SSRIs group (63.3% and 72.2%), but the difference between the groups was not statistically significant. The Agomelatine group had fewer adverse reactions (14.4% and 16.7%), but there was a slightly higher incidence of liver function impairment (6.7% and 4.4%), with no statistically significant difference between the groups. CONCLUSION: Agomelatine, as a novel antidepressant, shows certain advantages in improving depression and anxiety symptoms and is comparable to SSRIs in terms of safety. However, its long-term efficacy and safety on MDD or other depressive subtypes still require further observation and research.

3.
Bioprocess Biosyst Eng ; 44(9): 1901-1912, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33864126

RESUMO

Carbon dioxide supplementation is significant for cell growth in autotrophic cultures of microalgae. However, the CO2 utilization efficiency is quite low in most processes. Aimed at this problem, six kinds of physical absorption enhancers were investigated to enhance the biological carbon sequestration of microalgae. By the addition of a small amount of CO2 absorption enhancer, the total inorganic carbon concentration of the medium was significantly increased. In addition, the biomass productivity of Scenedesmus dimorphus was maximally increased by 63% by the addition of propylene carbonate in flask cultures. In cultures using an air-lift photobioreactor equipped with a pH-feedback control system to supply CO2, the CO2 consumption was maximally reduced by 71% with added polyethylene glycol dimethyl ether. This study indicates that the incorporation of physical absorption enhancers could be a promising approach to overcome the problems of low CO2 utilization efficiency and high carbon source cost in algal biomass production.


Assuntos
Dióxido de Carbono/metabolismo , Microalgas/crescimento & desenvolvimento , Fotobiorreatores , Scenedesmus/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio
4.
Bioprocess Biosyst Eng ; 43(12): 2243-2252, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32671549

RESUMO

Heterotrophic or mixotrophic culture of microalgae is feasible alternative approach to avoid light limitation in autotrophic culture. However, only a few kinds of organic carbon sources are available for algal culture. Disaccharides, such as sucrose, are difficult to be utilized by microalgae under both heterotrophic and mixotrophic conditions. In this study, a symbiotic yeast was accidentally found in a contaminated algal suspension. The symbiotic yeast was isolated and identified as Cryptococcus sp. This yeast was able to extracellularly hydrolyze sucrose and accumulated monosaccharides in the medium. It can enhance algal growth using sucrose as the carbon source at both heterotrophic and mixotrophic modes when mix-cultured with Chlorella pyrenoidosa. The highest algal cell density of 118.8 × 106 and 151.2 × 106 cells/mL was achieved with a final algal percentage of 83.5 and 93.2% at heterotrophic and mixotrophic culture, respectively. Furthermore, the protein and lipid content was significantly enhanced by mix-culture C. pyrenoidosa with Cryptococcus YZU-1. The fatty acid accumulated in this co-culture system was suitable for the production of biodiesel. This symbiotic yeast solved the problem that C. pyrenoidosa cannot heterotrophically or mixotrophically utilize sucrose. A high algae density was obtained and the protein and lipid accumulation were also significantly enhanced. This study provided a novel approach for production of protein or lipid-rich biomass using sucrose or sucrose-rich wastes as the carbon source.


Assuntos
Carbono/metabolismo , Chlorella/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Sacarose/metabolismo , Processos Autotróficos , Biocombustíveis , Biomassa , Carboidratos/química , Chlorella/microbiologia , Técnicas de Cocultura , Dissacarídeos , Ácidos Graxos/metabolismo , Processos Heterotróficos , Microbiologia Industrial , Lipídeos/biossíntese , Lipídeos/química , Microalgas/crescimento & desenvolvimento , Microalgas/metabolismo , Monossacarídeos/metabolismo , Filogenia , Sacarose/química , Temperatura
5.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(6): 735-741, 2020 Nov.
Artigo em Zh | MEDLINE | ID: mdl-33236593

RESUMO

OBEJECTIVE: To investigate the role of a novel chemically defined medium (CDM) in the regulation of dental papilla cells (DPCs) functional phenotype in vitro and periodontal bone regeneration in vivo. METHODS: DPCs were isolated and cultured in conventional medium (CM) or CDM. The surface makers, and the proliferation, migration and osteogenic differentiation abilities of DPCs were evaluated. In vivo, the DPCs that mixed with collagen gel were implanted into the model rats in the defect of periodontal to repair the periodontal tissue. Regeneration of the tissues was examined by microcomputed tomography and histological observation. RESULTS: DPCs in the CM group and CDM group showed similar surface markers. Compared to the CM group, the CDM significantly enhanced the proliferation, colony-forming efficiency and migration of DPCs in vitro. In addition, real time PCR showed that the expression levels of osteogenesis-related genes, Runx2, Alp and Opn. were significantly enhanced in DPCs in the CDM group. DPCs cells treated with CDM also exhibited higher alkaline phosphatase activity and stronger ability of formation of mineralized nodules in vitro. In vivo, DPCs from CDM group significantly enhanced the periodontal bone regeneration and the reconstruction of periodontal bone tissues in rat periodontal defect model. CONCLUSION: CDM is a suitable medium to culture DPCs for periodontal bone regeneration. This research provided a substitute for basic research and set the stage for future clinical application of stem cell transplantation.


Assuntos
Osteogênese , Ligamento Periodontal , Animais , Regeneração Óssea , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Papila Dentária , Ratos , Regeneração , Microtomografia por Raio-X
6.
Zhonghua Nan Ke Xue ; 25(3): 223-230, 2019 Mar.
Artigo em Zh | MEDLINE | ID: mdl-32216240

RESUMO

OBJECTIVE: To investigate the incidence of chromosome polymorphisms and their influence on semen quality and sperm DNA integrity in male patients receiving in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI). METHODS: We retrospectively analyzed the chromosomal karyotypes and the types and incidence rate of chromosome polymorphisms in 2 370 male patients undergoing IVF/ICSI between June 2016 and June 2018. We classified the patients into groups A (with variation in the secondary constriction region in the autosomal long arm), B (with variation in the short arm of the D/G group chromosomes), C (with interbrachial inversion of chromosome 9) and D (with Y chromosome polymorphisms), and compared the semen parameters and sperm DNA fragmentation indexes (DFI) between the patients with chromosome polymorphisms and those with normal chromosomes. RESULTS: Totally, 154 (6.50%) of the patients undergoing IVF/ICSI were found with chromosome polymorphisms, including 34 cases of secondary constriction variation in the long arm of the autosome (1.43% ï¼»34/2 370ï¼½, 22.08% ï¼»34/154ï¼½), 82 cases of short arm polymorphisms of the D/G group chromosomes (3.46% ï¼»82/2 370ï¼½, 53.25% ï¼»82/154ï¼½), 26 cases of interbrachial inversion of chromosome 9 (1.10% ï¼»26/2 370ï¼½, 16.88% ï¼»26/154ï¼½), 10 cases of Y chromosome polymorphisms (0.42% ï¼»10/2 370ï¼½, 6.50% ï¼»10/154ï¼½), and 2 cases of mixed chromosome polymorphisms (0.08% ï¼»2/2 370ï¼½, 1.42% ï¼»2/154ï¼½). The total sperm count was lower in group D than in the other polymorphism groups and the normal chromosome group, but with no statistically significant difference among the five groups (P > 0.05). The sperm progressive motility was also lower in group D than in the other five groups, with statistically significant difference from group B (27.5 ± 13.5 vs. 41.5 ± 21.1, P = 0.027), but not from the other groups (P > 0.05). No statistically significant difference was observed in the sperm DFI between the polymorphism groups and the normal chromosome group (P > 0.05), or among the polymorphism groups (P > 0.05). The proportion of normal semen was lower in group D than in the other four groups, but with no statistically significant difference among the five groups (P > 0.05). The incidence rate of asthenospermia was higher in group D than in the other four groups, but with no statistically significant difference among the five groups (P > 0.05), and so was that of oligoasthenospermia, with statistically significant difference from the normal chromosome group (30.0% vs 8.0%, P = 0.041), but not from the other polymorphism groups (P > 0.05). CONCLUSIONS: Short arm polymorphisms of the D/G group chromosomes are the most common type of chromosome polymorphisms in male patients undergoing IVF/ICSI. Polymorphisms of the Y chromosome have a negative effect on semen quality, while those of the other chromosomes do not significantly affect semen quality and sperm DNA integrity.


Assuntos
Cromossomos Humanos/genética , Fragmentação do DNA , Análise do Sêmen , Injeções de Esperma Intracitoplásmicas , DNA , Humanos , Masculino , Estudos Retrospectivos , Espermatozoides
7.
World J Clin Cases ; 11(32): 7895-7899, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-38073685

RESUMO

BACKGROUND: Tardive dyskinesia (TD) is a serious and disabling movement disorder; it impairs social function and quality of life and increases the mortality rate. TD is usually induced by the use of antipsychotic drugs; however, the underlying mechanism remains unclear. Pharmacotherapy of TD includes cholinergic drugs, benzodiazepines, ginkgo biloba extract (GBE), antioxidants, amantadine, propanolol, botulinum toxin, valbenazine, and deutetrabenazine, whereas the non-pharmacotherapy approach includes modified electroconvulsive therapy (MECT) and deep brain stimulation. We successfully treated a chronic schizophrenia patient with comorbid long-term severe TD using deutetrabenazine, clozapine, and MECT. CASE SUMMARY: A 69-year-old woman who was diagnosed as having schizophrenia 16 years ago developed severe TD after 6-mo prescription of risperidone oral solution. Her TD symptoms did not resolve despite various treatments, such as GBE, vitamin E, trihexyphenidyl, promethazine, benzodiazepines, and switching to quetiapine and olanzapine. After admission, she was given deutetrabenazine 6 mg bid. Her buccal tremor was slightly resolved 3 d later; however, her tongue remained protruded and could not be retracted. Quetiapine was switched to clozapine on day 4, and the buccal tremor remarkably resolved, and the tongue could be retracted into the mouth from day 6 onward. After three sessions of MECT, the buccal tremor resolved further. Since then, she has been able to take a semifluid diet, and her quality of life improved remarkably during 6 mo of follow-up. CONCLUSION: TD is a serious condition which could be caused by antipsychotic medications; however, the best strategy against TD is prevention and monitoring during using antipsychotics. For patients with TD caused by antipsychotic medication use, multiple measures should be considered like switching to clozapine, adjunction with deutetrabenazine, or even MECT.

8.
World J Psychiatry ; 13(6): 331-339, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37383283

RESUMO

There are various types of traumatic stimuli, such as catastrophic events like wars, natural calamities like earthquakes, and personal trauma from physical and psychological neglect or abuse and sexual abuse. Traumatic events can be divided into type I and type II trauma, and their impacts on individuals depend not only on the severity and duration of the traumas but also on individuals' self-evaluation of the traumatic events. Individual stress reactions to trauma include posttraumatic stress disorder (PTSD), complex PTSD and trauma-related depression. Trauma-related depression is a reactive depression with unclear pathology, and depression occurring due to trauma in the childhood has gained increasing attention, because it has persisted for a long time and does not respond to conventional antidepressants but shows good or partial response to psychotherapy, which is similar to the pattern observed for PTSD. Because trauma-related depression is associated with high risk of suicide and is chronic with a propensity to relapse, it is necessary to explore its pathogenesis and therapeutic strategy.

9.
Front Bioeng Biotechnol ; 10: 1072942, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36532587

RESUMO

During the heterotrophic cultivation of microalgae, a cooled process against temperature rise caused by the metabolism of exogenous organic carbon sources greatly increases cultivation cost. Furthermore, microalgae harvesting is also a cost-consuming process. Cell harvesting efficiency is closely related to the characteristics of the algal cells. It may be possible to change cell characteristics through controlling culture conditions to make harvesting easier. In this study, the mesophilic Chlorella pyrenoidosa was found to be a thermal-tolerant species in the heterotrophic mode. The cells could maintain their maximal specific growth rate at 40°C and reached 1.45 day-1, which is equivalent to that of cultures at 35°C but significantly higher than those cultured at lower temperatures. Interestingly, the cells cultured at 40°C were much easier to be harvested than those at lower temperatures. The harvesting efficiency of the cells cultured at 40°C reached 96.83% after sedimentation for 240 min, while the cells cultured at lower temperatures were reluctant to settle. Likely, the same circumstance occurred when cells were harvested by centrifugation or flocculation. The promotion of cell harvesting for cells cultured at high temperatures was mainly attributed to increased cell size and decreased cell surface charge. To the best of our knowledge, this is the first report that cells cultured at high temperatures can promote microalgae harvesting. This study explores a new approach to simplify the cultivation and harvesting of microalgae, which effectively reduces the microalgae production cost.

10.
Bioresour Technol ; 361: 127625, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35850393

RESUMO

A novel method of one-step co-cultivation and harvesting of microalgae and fungi, for efficient starch wastewater treatment and high-value biomass production was developed. By combination of Aspergillus oryzae and Chlorella pyrenoidosa, nutrients in wastewater could be converted to useful microbial biomass, while the wastewater was purified. Moreover, the microalgae C. pyrenoidosa could gradually be encapsulated in fungal pellets which promoted the biomass harvesting. The free algal cells could be completely harvested by fungal pellets within 72 h. The synergistic effects between them greatly improved the removal efficiencies of main pollutants as the removal efficiency of COD, TN, and TP reached 92.08, 83.56, and 96.58 %, respectively. In addition, the final biomass concentration was higher than that of individual cultures. The protein and lipid concentration was also significantly improved and reached 1.92 and 0.99 g/L, respectively. This study provides a simple and efficient strategy for simultaneous wastewater treatment and high-value biomass production.


Assuntos
Chlorella , Microalgas , Biomassa , Chlorella/metabolismo , Floculação , Fungos , Microalgas/metabolismo , Amido/metabolismo , Águas Residuárias/microbiologia
11.
Chemosphere ; 291(Pt 1): 132868, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34767848

RESUMO

Exorbitant substrates for Schizochytrium culture result in the high cost of docosahexaenoic acid (DHA) production. In order to develop a feasible approach that is expected to reduce DHA production cost, Schizochytrium sp. S31 cultivation with a mixture of saline wastewater (SWW) and tofu whey wastewater (TWW) was investigated in this study. Using glucose as the carbon source, the maximum biomass and DHA yield in cultures using mixed wastewater containing 5% SWW reached 19.08 and 2.66 g/L, respectively, which were 2.29 and 2.66 times higher than those of cultures using control medium. Moreover, a good wastewater treatment performance was achieved as approximately 60% of the COD, TN, and TP were reduced in the cultures using mixed wastewater with a SWW ratio of 5%. The mixed wastewater presented better performance on DHA production than control medium using all tested carbon sources including glucose, fructose, and pure and crude glycerol. The components of control medium can be completely replaced by the mixed wastewater and crude glycerol. It is expected to effectively decrease the medium cost for DHA production and reduce the environmental risk of food processing wastewater.


Assuntos
Ácidos Docosa-Hexaenoicos , Estramenópilas , Biomassa , Fermentação , Glicerol , Águas Residuárias
12.
Sci Total Environ ; 710: 136448, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32050374

RESUMO

Docosahexaenoic acid plays a vital role in human health as it is essential for the proper function of the nervous system and for visual functions. To decrease the cost of docosahexaenoic acid production by Schizochytrium, the cost of the medium should be further decreased. In this study, the use of tofu whey wastewater to culture Schizochytrium sp. for docosahexaenoic acid production was tested, with the goal of reducing the medium cost. The results indicated that tofu whey wastewater presented a better culture performance with respect to biomass, lipid, and docosahexaenoic acid production compared with three traditional media. Through simple pH adjustment, the biomass and docosahexaenoic acid productivity reached 1.89 and 0.24 g/L/day, respectively, which were much higher than those obtained using traditional medium. The removal efficiency of chemical oxygen demand, total nitrogen, and total phosphorus reached 64.7, 66.0, and 59.3%, respectively. Due to the rich nutrients in tofu whey wastewater, the use of extra nitrogen source was avoided and the total medium cost for docosahexaenoic acid production in cultures using tofu whey wastewater was <1/3 of that of traditional media. This result indicated that tofu whey wastewater is an effective and economic basal medium for docosahexaenoic acid production by Schizochytrium sp.


Assuntos
Alimentos de Soja , Soro do Leite , Biomassa , Ácidos Docosa-Hexaenoicos , Fermentação , Nutrientes , Águas Residuárias
13.
Math Biosci Eng ; 17(1): 700-724, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31731372

RESUMO

This paper proposes a multi-threshold image segmentation method based on modified salp swarm algorithm (SSA). Multi-threshold image segmentation method has good segmentation effect, but the segmentation precision will be affected with the increase of threshold number. To avoid the above problem, the slap swarm optimization algorithm (SSA) is presented to choose the optimal parameters of the fitting function and we use levy flight to improve the SSA. The solutions are assessed using the Kapur's entropy, Otsu and Renyi entropy fitness function during the optimization operation. The performance of the proposed algorithm is evaluated with several reference images and compared with different group algorithms. The results have been analyzed based on the best fitness values, peak signal to noise ratio (PSNR), and feature similarity index measures (FSIM). The experimental results show that the proposed algorithm outperformed other swarm algorithms.

14.
Eng Life Sci ; 19(2): 104-111, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32624992

RESUMO

Botryococcus braunii was cultured in different light path length under different incident light intensity to investigate the effect of light on alga growth as well as hydrocarbon and fatty acid accumulation. Results indicated that longer light path length required higher incident light intensity in order to meet the light requirement of algal growth and hydrocarbon accumulation during the course of cultivation. However, hydrocarbon profile was only affected by the incident light intensity and not influenced by the light path length. High incident light intensity enhanced the accumulation of hydrocarbons with longer carbon chains. Besides, the fatty acid content and profiles were significantly influenced by both incident light intensity and light path. Higher fatty acid content and higher percentage of C18 and monounsaturated fatty acid components were achieved at the higher incident light intensity and lower light path length. Taken together, these results are benefit to improve its biomass and oil productivity through the optimization of light and photobioreactor design.

15.
Bioresour Technol ; 253: 79-84, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29331517

RESUMO

Tofu whey wastewater (TWW) is an abundant, nutrient riched and safety wastewater and is regarded as an excellent alternative medium in fermentation. In this study, the feasibility of algal cultivation using TWW as the basal medium was investigated. Results indicated that through simple pH adjustment, TWW presented a better culture performance at autotrophic, heterotrophic, and mixotrophic modes compared with that of regular green algae medium, BG-11. The biomass productivities of Chlorella pyrenoidosa at each trophic mode were 4.76, 1.97, and 2.08 times higher than that cultured in BG-11 medium, respectively. Although a comparative or even lower lipid and protein content was obtained, much higher lipid and protein productivities were obtained in TWW compared to that of BG-11. The algal biomass accumulated in TWW can be used to produce high-value products. Therefore, TWW is a better alternative medium for efficient algal culture.


Assuntos
Microalgas , Alimentos de Soja , Águas Residuárias , Biomassa , Chlorella , Lipídeos , Soro do Leite
16.
Bioresour Technol ; 249: 425-430, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29065324

RESUMO

Glucose is normally used as the carbon source for heterotrophic cultivation of algal cells, whereas sucrose is difficult to be heterotrophicly utilized by them. In this study, a new co-culture system was developed through mixed culture of Chlorella pyrenoidosa with immobilized Saccharomyces cerevisiae in the dark to effectively obtain pure algal suspension using sucrose as only carbon source. In this system, a pure algal suspension with a concentration of 2.08g/L was obtained. The lipid content reached 29%, which was higher than that obtained in glucose contained system. In addition, the immobilized yeast beads were repeatedly used for at least three times. Through immobilization, the choice for the yeast strains that are able to hydrolyze sucrose was not limited by its product and pure algal suspension was efficiently obtained. This strategy may effectively decrease the cost of carbon source in the heterotrophic cultivation of microalgae.


Assuntos
Chlorella , Sacarose , Biomassa , Carbono , Técnicas de Cocultura , Processos Heterotróficos , Lipídeos , Microalgas
17.
J Int Med Res ; 44(6): 1283-1291, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28322098

RESUMO

Objective To investigate the effect of sperm DNA fragmentation on the fertilization rate, embryo development and pregnancy outcome of in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) in a cohort of Chinese couples. Methods Infertile couples that had undergone assisted reproductive technology at our centre between January 2011 and December 2013 were included in this retrospective study. Fractions of prepared sperm samples were evaluated for sperm DNA fragmentation on the day of oocyte recovery. Results Of the 550 couples selected, 415 had undergone IVF and 135 ICSI. Sperm DNA fragmentation rate was significantly negatively correlated with the fertilization rate in the ICSI cycles but not the IVF cycles. No association was found between sperm DNA fragmentation and cleavage rate or good quality embryo formation rates in IVF or ICSI cycles. Receiver operating characteristic (ROC) curve analysis showed that the sperm DNA fragmentation rate was a statistically significant prognostic indicator of the clinical fertilization rate in ICSI cycles; a rate > 22.3% was associated with a lower fertilization rate following ICSI compared with a rate ≤ 22.3%. Conclusions High values of sperm DNA fragmentation were associated with a low fertilization rate following ICSI but were not associated with alterations in pregnancy or live birth rates in either ICSI or IVF in this cohort of Chinese couples.


Assuntos
Fragmentação do DNA , Fertilização in vitro , Infertilidade Masculina/terapia , Taxa de Gravidez/tendências , Injeções de Esperma Intracitoplásmicas , Espermatozoides/patologia , Adulto , Transferência Embrionária , Feminino , Humanos , Infertilidade Masculina/patologia , Masculino , Oligospermia/patologia , Oócitos/citologia , Oócitos/fisiologia , Gravidez , Resultado da Gravidez , Curva ROC , Estudos Retrospectivos , Motilidade dos Espermatozoides
18.
ACS Appl Mater Interfaces ; 6(1): 109-15, 2014 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-24364715

RESUMO

Magnetic flocculant was synthesized for the highly efficient recovery of microalgal cells. The highest flocculation was achieved using the magnetic flocculant synthesized with iron oxide and 0.1 mg/mL cationic polyacrylamide (CPAM). This resulted in a recovery efficiency of more than 95% within 10 min using a dosage of 25 mg/L for Botryococcus braunii and 120 mg/L for Chlorella ellipsoidea. For both species, the adsorption isotherm data fit the Freundlich model better than the Langmuir model, indicating that the adsorption process was a heterogeneous multilayer. The maximum adsorption capacity was 114.8 and 21.4 mg dry cells/mg-particles at pH 7 for B. braunii and C. ellipsoidea, respectively. The primary flocculation mechanism was bridging, which was assisted by the electrostatic interactions between the microalgal cells and the magnetic flocculant under acidic conditions. These results provide new opportunities and challenges for understanding and improving the harvesting of microalgae using magnetic separation.


Assuntos
Floculação , Magnetismo , Microalgas/isolamento & purificação , Adsorção , Biomassa , Termodinâmica
19.
Bioresour Technol ; 156: 117-22, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24495537

RESUMO

The cultivation of Chlorella ellipsoidea in bubble column bioreactors was investigated at different scales under indoor and outdoor conditions. The algal cells were able to quickly adapt to the outdoor conditions and achieved a growth rate of 31.55mg L(-1)day(-1). Due to differences in light and temperature, the outdoor culture produced a higher percentage of unsaturated fatty acids compared to the indoor cultures, while the amino acid composition was unaffected. The overall cost of the biomass produced by the 200L outdoor cultivation (58.70US$/kg-dry weight) was estimated to be more than 7 times lower than that of the 20L indoor cultivation (431.39US$/kg-dry weight). Together these results provide a basis for the cultivation of C. ellipsoidea for the large-scale production of biofuels, high-value nutrients and/or recombinant proteins.


Assuntos
Reatores Biológicos , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Chlorella/crescimento & desenvolvimento , Proteínas de Algas/metabolismo , Aminoácidos/metabolismo , Técnicas de Cultura de Células/economia , Custos e Análise de Custo , Ácidos Graxos/metabolismo , Cinética
20.
Bioresour Technol ; 167: 376-82, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24998478

RESUMO

An integrated system combining ultrasound-intensified outdoor cultivation of Botryococcus braunii with in situ magnetic harvesting of the algal cells was developed. The algal cells were cultivated in 200 L plastic bag reactors, and seven five-minute ultrasonic treatments at a four-day interval using a fixed frequency of 40 kHz and a total power of 300 W improved algal cell biomass and hydrocarbon productivity. The algal cells were harvested using functional magnetic particles and a magnetic separator, and a recovery efficiency of 90% was obtained under continuous operation at a flow rate of 100mL/min using the in situ magnetic separation system. The overall production cost using the integrated system was US$ 25.14 per kilogram of B. braunii dry biomass. The system developed in this study provides a base for the industrial production of B. braunii.


Assuntos
Técnicas de Cultura de Células/métodos , Clorófitas/crescimento & desenvolvimento , Magnetismo/métodos , Ultrassom/métodos , Técnicas de Cultura de Células/economia , Clorófitas/metabolismo , Hidrocarbonetos/metabolismo , Cinética , Lipídeos/biossíntese , Magnetismo/economia , Termodinâmica
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