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@#Abstract: Objective To explore the spatial epidemiological characteristics of severe cases hand, foot and mouth disease (HFMD) in Guangxi, China, from 2014 to 2018, and to provide a basis for identifying the high-risk regions as well as the prevention and control of severe cases of HFMD in Guangxi. Methods Spatial-temporal scanning analysis, global and local spatial autocorrelation analysis were used to analyze the spatial clustering of HFMD. The trend surface analysis was used to evaluate the spatial distribution trend of HFMD. Results From 2014 to 2018, the incidence and severe case fatality rates of HFMD were 3.89/100 000 and 4.23%, respectively. Monte Carlo scanning analysis showed that the first cluster region was Cenxi City, the second cluster was mainly concentrated in northwest of Guangxi, and the aggregation time was mainly concentrated in April to May and August to October. The global spatial autocorrelation analysis showed that the severe HFMD was significant clustering distribution, and the Moran's I coefficients of the sever cases, severe morbidity and severe case fatality rate were 0.088, 0.118, 0.197, respectively (P<0.05). Local spatial autocorrelation analysis showed that hotspots of severe HFMD cases were concentrated in the southern Guangxi, mainly in Lingshan County. Anselin local Moran's I clustering and outlier analysis indicated that 5 high-high (H-H) clustering regions for fatality were Lingshan, Pubei, Zhongshan, Zhaoping and Pinggui County. There were 6 high-high (H-H) clustering regions for severe incidence rate, namely Lingshan, Qinnan, Lingyun, Youjiang, Bama Yao Autonomous and Pinggui County, and 1 high-low (H-L) clustering region, Cenxi County. The trend surface analysis showed that the overall number of severe cases of death decreased from east or west to the middle, and increased from north to middle, and then decreased to south. Conclusions Severe HFMD cases in Guangxi have obvious spatial-temporal clustering, and the hop spots are mainly concentrated in southern Guangxi. The prevention and control of HFMD in areas with high incidence of severe cases should be strengthened to reduce the burden of HFMD cases.
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Percutaneous dilatational tracheostomy (PDT) is an increasingly popular method with several advantages, such as being able to perform at bedside with a simple kit, with a less number of medical staff and less amount of time. PDT is easier to perform, offers less bleeding risks and post-operative infection rates compared to conventional surgical tracheotomy. However, PDT is being performed more in the pulmonology and intensive care medicine than in otolaryngology. Herein, we introduce PDT and share our experiences, hoping otolaryngologists use our procedure more.
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Proximal flow control achieved with a balloon guide catheter (BGC) during endovascular treatment of acute ischemic stroke is reviewed in this article. In clinical practice, BGCs offer a multi-faceted approach for clot retrieval by creating proximal flow arrest, reducing embolic burden, and shortening procedure time. Evaluation of frontline thrombectomy procedures with BGCs revealed advantages of combined use over the conventional guide catheter (CGC), notably in the significant reduction of distal emboli to both the affected and previously unaffected territories. Recently, new measures of early and complete reperfusion at first thrombectomy pass have been identified as independent predictors of improved outcomes, which were consistently demonstrated with use of BGC as a safe and effective option to minimize number of passes during intervention. Prior randomized controlled trials reported the positive correlation between BGC-treated patients and a lower risk of mortality as well as shortened procedure time. While BGC use is more common in stent retriever-mediated mechanical thrombectomy, preliminary data has shown the potential benefit of device application during contact aspiration thrombectomy to achieve successful recanalization. However, the question of which major endovascular strategy reigns superior as a frontline remains to be answered. Along with clinical case assessments, BGC performance during in-vitro simulation was analyzed to further understand mechanisms for optimization of thrombectomy technique.
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Korea was verified as a measles-free country by the World Health Organization in 2014;however, some imported measles cases and related outbreaks were reported. As the incidence of wild-type measles decreases in measles-free countries, the proportion of vaccine-associated measles is increasing. Wild-type measles is highly contagious and requires follow-up and management of the contacts, whereas vaccine-related measles is not contagious and does not require follow-up intervention. Therefore, measles genotyping should be performed to reliably distinguish between them in suspected patients. Two patients with vaccine-associated measles were confirmed through genotyping at Daegu Fatima Hospital. In Korea, there are only a few reports of vaccine-associated measles confirmed through genotyping; thus, we report recent vaccine-associated measles cases, emphasizing the need for genotyping.
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Korea was verified as a measles-free country by the World Health Organization in 2014;however, some imported measles cases and related outbreaks were reported. As the incidence of wild-type measles decreases in measles-free countries, the proportion of vaccine-associated measles is increasing. Wild-type measles is highly contagious and requires follow-up and management of the contacts, whereas vaccine-related measles is not contagious and does not require follow-up intervention. Therefore, measles genotyping should be performed to reliably distinguish between them in suspected patients. Two patients with vaccine-associated measles were confirmed through genotyping at Daegu Fatima Hospital. In Korea, there are only a few reports of vaccine-associated measles confirmed through genotyping; thus, we report recent vaccine-associated measles cases, emphasizing the need for genotyping.
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OBJECTIVE: To discuss the role of proficiency testing program for pharmaceutical dissolution determination in the capacity building of relevant laboratories. METHODS Based on the results of the two proficiency testing programs carried out in recent years, analyze the difference of the quality management and the level of dissolution determination among the participating laboratories and discuss on the way that the proficiency testing programs carried out in future. RESULT: There is difference among the laboratories in both the quality management and the level of dissolution determination, the "unsatisfactory" laboratories mainly concentrated in local drug control institutes and pharmaceutical manufacturers. The three "unsatisfactory" laboratories in the first program, took corrective and preventive measures, participated in the later program, and achieved "satisfactory" results. CONCLUSION: The proficiency testing program is effective in improving the dissolution determination capacity of the participating laboratories and is recommended to be conducted continually in the pharmaceutical industry.
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PURPOSE: Pressure garment is the most effective tool in treatment of burn scar hypertrophy. But most patients feel discomfort to pressure garment. So tubular compressive bandage (TCB; Tubifast™) is widely used as a substitute. We checked daily pressure of tubular pressure bandage for 6 days and tried to find out the proper use. METHODS: Three doctors and two nurses were included in this study. They wore the TCB on both arms. One arm worn with one layer and the other arm with two layers. For six days, we checked the average pressure on arm and forearm with Picopress®. We used the SPSS (PASW statistics 18) as a statistics. RESULTS: During the first three days the pressure was markedly declined on both arm and forearm when with two layers. After then the pressure showed plateau. But one layer showed slow and continuous declining. The plateau pressure was above 10 mmHg with two layers and below 7 mmHg with one layer. CONCLUSION: Wearing the tubular compressive bandage (TCB; Tubifast™) is better with two layers than one layer and must be changed it in every 4 days.
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Humans , Arm , Bandages , Burns , Cicatrix , Cicatrix, Hypertrophic , Clothing , Forearm , HypertrophyABSTRACT
<p><b>OBJECTIVE</b>To evaluate the efficacy and safety of ribavirin aerosol in children with hand-foot-mouth disease (HFMD).</p><p><b>METHODS</b>A randomized, double-blind, placebo-controlled trial was performed. A total of 119 children with mild HFMD were randomly divided into an observed group (n=59) and a control group (n=60). In the observed group, ribavirin aerosol was given four times within the first hour, followed by once every other hour for the remaining time of the day and day 2; from days 3 to 7, it was given 4 times per day, with 2-3 sprays every time, for 7 days. In the control group, placebo was given in the same way as in the observed group. Additionally, both groups used oral antiviral liquid. The scores of clinical symptoms including oral ulcer, skin rash, nasal congestion, runny nose, sneezing, cough, and fever before and after treatment were recorded to evaluate treatment outcomes. Throat swabs were taken before treatment and 5-7 days after treatment to measure viral load by RT-PCR and to compare the negative conversion rate between the two groups.</p><p><b>RESULTS</b>Fifty-seven patients in the observed group and 56 patients in the control group were tested according to the original research design. After 5-7 days of treatment, the observed group had a significantly higher overall negative conversion rate of enterovirus than the control group (P<0.01). The overall marked response rate and overall response rate of the observed group were 89% and 89%, respectively, significantly higher than those of the control group (29% and 43%). During treatment, there were no adverse reactions such as dizziness, vomiting, and notable decreases in hemoglobin, white blood cells, and platelets in the two groups.</p><p><b>CONCLUSIONS</b>Ribavirin aerosol can be effectively and safely used for treating mild HFMD. With low dosage and few adverse reactions, it holds promise for clinical application.</p>
Subject(s)
Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Aerosols , Antiviral Agents , Therapeutic Uses , Double-Blind Method , Hand, Foot and Mouth Disease , Drug Therapy , Ribavirin , Therapeutic UsesABSTRACT
<p><b>OBJECTIVE</b>To investigate the effects of free and pedicled thoracodorsal artery perforator (TDAP) flaps for repairing skin and soft tissue defects in limbs, neck, axillary and shoulder.</p><p><b>METHODS</b>From October 2009 to Auguest 2011, 16 TDAP flaps were used to repair skin and tissue defects. Among them, five ipsilateral pedicled flaps were used to repair wounds in neck, axillary and shoulder. 11 free TDAP flaps were used to repair the wounds with bone or tendon exposure. In 12 cases, the flaps were pedicled with thoracodorsal artery and vein-lateral branches-perforators, in 4 cases, pedicled with thoracodorsal artery and vein-serratus anterior muscular branches-perforators. The deep fascia, the latissimus dorsi and thoracodorsal nerve were not included in all flaps. The flaps size ranged from 10 cm x 5 cm to 26 cm x 10 cm.</p><p><b>RESULTS</b>All 16 flaps survived completely with primary healing both at donor site and recipent area. After a follow-up of 3 to 24 months, all flaps gained good texture and appearance. Only linear scar was left at donor area. The shoulder could move freely.</p><p><b>CONCLUSIONS</b>TDAP flap has good texture, long vascular pedicle,and reliable blood supply, leaving less morbidity at donor site. The latissimus dorsi and thoracodorsal nerve are also preserved. The pedicled TDAP flap is an ideal flap for repairing the ipsilateral skin and soft tissue defects of the neck, shoulder, axillary. The free TDAP flap is suited for repairing skin and soft tissue defects of the extremities.</p>
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Humans , Arteries , Axilla , Muscle, Skeletal , Perforator Flap , Transplantation , Surgical Flaps , Transplantation , Thoracic Wall , Wound Healing , Wounds and Injuries , General SurgeryABSTRACT
The paper reports the systematic study on felodipine and its impurities in tablets, to improve its quality standards for the control of the related substances. HPLC-DAD, UPLC-MS, IR and NMR methods were used for the isolation of felodipine and its impurities in tablets, their identification and the zebrafish animal model was used for the analysis of the toxic impurities. In felodipine material and its tablets, three impurities are isolated and identified. They are impurity 1 [dimethyl 4-(2, 3-dichlorophenyl)-2, 6-dimethyl-1, 4-dihydropyridine-3, 5-dicarboxylate], impurity 2 [ethyl methyl 4-(2, 3-dichlorophenyl)-2, 6-dimethylpyridine-3, 5-dicarboxylate] and impurity 3 [diethyl 4-(2, 3-dichlorophenyl)-2, 6-dimethyl-1, 4-dihydropyridine-3, 5-dicarboxylate], separately. The result of zebrafish animal model analysis showed that the teratogenic effects of four compounds were: impurity 3 > or = felodipine > impurity 1 > impurity 2, lethal effects were as follows: impurity 2 = impurity 3 > felodipine > or = impurity 1. This study confirmed the toxicity of three impurities in felodipine. According to the results, the paper suggested the amendments to the standard of the medicine and provided the support to the control of impurities in the manufacturing process.
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Animals , Abnormalities, Drug-Induced , Antihypertensive Agents , Chemistry , Toxicity , Calcium Channel Blockers , Chemistry , Toxicity , Chromatography, High Pressure Liquid , Methods , Drug Contamination , Felodipine , Chemistry , Toxicity , Magnetic Resonance Spectroscopy , Molecular Structure , Pharmaceutical Preparations , Chemistry , Quality Control , Spectrophotometry, Infrared , Tablets , Tandem Mass Spectrometry , ZebrafishABSTRACT
Spontaneous rupture of a primary cardiac angiosarcoma is a rare condition with a poor prognosis. The authors describe the case of a 48-year-old man with abnormal blood flow from a pericardial mass to the right atrium 3 months after pericardiocentesis. The flow was presumed to have occurred due to rupture of this cardiac angiosarcoma of the right atrial wall and pericardium into the right atrial cavity.
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Humans , Middle Aged , Echocardiography , Heart Atria , Hemangiosarcoma , Pericardiocentesis , Pericardium , Prognosis , Rupture , Rupture, SpontaneousABSTRACT
Spontaneous rupture of a primary cardiac angiosarcoma is a rare condition with a poor prognosis. The authors describe the case of a 48-year-old man with abnormal blood flow from a pericardial mass to the right atrium 3 months after pericardiocentesis. The flow was presumed to have occurred due to rupture of this cardiac angiosarcoma of the right atrial wall and pericardium into the right atrial cavity.
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Humans , Middle Aged , Echocardiography , Heart Atria , Hemangiosarcoma , Pericardiocentesis , Pericardium , Prognosis , Rupture , Rupture, SpontaneousABSTRACT
A marine unicellular green alga, Platymonas subcordiformis, was demonstrated to photobiologically produce hydrogen gas from seawater. The objective of this study was to localize and identify the hydrogenase isolated from P. subcordiformis. Adaptation in the presence of inhibitors of protein biosynthesis indicated that the hydrogenase was much more inhibited by cycloheximide than that by chloramphenicol. The result suggested that the hydrogenase isolated from P. subcordiformis is probably synthesized in cytoplasmic ribosomes. Both Western blot analysis and immunogold electron microscopy demonstrate that the P. subcordiformis hydrogenase is mainly located in the chloroplast stroma. The proteins that reacted specifically with the antibodies against the iron hydrogenase isolated from Chlamydomonas reinhardtii were concentrated by immunoprecipitation. The separated protein bands were cut out of the SDS-PAGE gel, in-gel digested by trypsin, and analyzed by Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS). Mascot was employed for analysis of the MALDI data using the public databases NCBInr. The hydrogenase isolated from P. subcordiformis was identified to be the Fe-hydrogenase.
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Algal Proteins , Metabolism , Biocatalysis , Blotting, Western , Chloramphenicol , Pharmacology , Chlorophyta , Cycloheximide , Pharmacology , Cytoplasm , Electrophoresis, Polyacrylamide Gel , Hydrogenase , Metabolism , Immunoprecipitation , Methods , Iron-Sulfur Proteins , Metabolism , Kinetics , Microscopy, Immunoelectron , Protein Synthesis Inhibitors , Pharmacology , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , MethodsABSTRACT
Objective To report the therapeutic effect of free dursum flap lnbule grafting to repair soft tissue defects in two or three fingers result from electric bum in just one operation.Methods Seven patients with electric injuries in two or three fingers were treated by the dorsum flap (or composite flap) lohule graft- ing.The procedure is followed:after dehridement,a trifoliated flap composed of medial pedal,first dorsal met- atarsal and lateral pedal flaps or a bifoliated flap composed of first dorsal metatarsal and lateral pedal flaps was designed.The combined flap contained anterior tihial artery and dorsal pedal artery as the stem vessel for anas- tomosing with the supplying vessel.The three tributaries of dorsal pedal artery:medial tarsal artery,first dor- sal metatarsal artery and lateral tarsal artery were enntained in the three leaves respectively.They could contain extensor digitorum longus tendons and cutaneous nerves and be used to cover the skin defect of two or three fin- gers,reconstruct the flexor tendons and finger arteries and nerves at the same time.Results All the flaps were survived completely,the wounds in all fingers healed primarily,however,skin graft in two feet necrosised partly,one got to healing required wound dressing for three weeks,another required further operation of trans- ferring medial supramalleolar flap due to tendon exposure.The patients were followed up from 3 to 24 months, all the flaps were of appropriate thickness,good texture and satisfactory sensation,all the fingers recovered good function of flection and extension except two fingers existing little limitation.Conclusion Free dorsum flap lohule grafting is an ideal way to treat electric injuries of multiple fingers because it can recnnstruct the skin,tendons,blood vessels and nerves in two or three fingers in just one operation.
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The instability of secondary metabolite production is a ubiquitous problem in plant cell culture. To understand the instability, the investigation of anthocyanin accumulation in suspension cultures of Vitis vinifera, as a model system, has been initiated in our laboratory. Suspension culture of a relatively homogeneous cell line E of V. vinifera, was established by long-term cell line selection by anthocyanin content differentiation. The aggregate size of E was smaller than that of other cell lines obtained by routine screening method. The variation coefficients of anthocyanin content in suspension cultures of E were 8.7% in long-term subcultures and 5% in repeated flasks, respectively. The effects of elicitor, precursor feeding and light irridiation on biomass and anthocyanin accumulation in suspension cultures of E had been investigated and the results showed that all the variation coefficients were lower than 12% and this indicated the importance of homogeneity on stable production in plant cell culture. With the combination treatment of 30micromol/L phenylalanine and 218micromol/L methyl jasmonate in the dark in suspension cultures of E, the anthocyanin content and production in suspension culture of E was 5.89-fold and 4.30-fold of the controls, respectively, and all the variation coefficients of biomass and anthocyanin accumulation were lower than those of the controls in 5 successive subcultures.
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Anthocyanins , Biomass , Cell Proliferation , Light , Suspensions , Vitis , Cell Biology , MetabolismABSTRACT
BACKGROUND: Renal function in patients, who undergo medical examination, is usually evaluated by the serum creatinine level. However this numerical value does not always represent the entire renal function because the values increases only when the renal function has decreased more than 50%. The purpose of this study was to find the prevalence of renal diseases through the GFR (Glomerular filtration rate) using MDRD (Modification of Diet in Renal Disease) equation and to analyze the risk factors related to renal diseases. METHODS: We reviewed all the clinical records of 440 patients who had visited for medical examination between January 1, 2004 and December 31, 2004. We have calculated the GFR for each group using the MDRD equation and then figured out the correlation between the GFR and its risk factors. RESULTS: Patients haing GFR of less than 60 mL/min/1.73 m2 were 19 (7.2%), 60~90 mL/min/1.73 m2 were 123 (46.4%) and more than 90 mL/min/1.73 m2 were 123 (46.2%). The correlation between the GFR and age, obesity, hypertension and diabetes melitus were observed as negative results in univariate analysis of variance (P<0.05). Age and diabetes melitus were independent factors affecting the GFR (OR=3.1, 2.2 respectively, P<0.05) in multiple logistic regression analysis. CONCLUSION: It is a well known fact that the declined renal function is related to the aging process and diabetes melitus. Therefore, the mortality rate caused by renal failure and its complications should be decreased through the control of diabetes melitus, aging process and other risk factors.
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Humans , Aging , Creatinine , Diet , Filtration , Hypertension , Logistic Models , Mortality , Obesity , Prevalence , Renal Insufficiency , Risk FactorsABSTRACT
<p><b>OBJECTIVE</b>To explore the results of repairing widespread defects of traumatic soft tissue in heel by microvascular anastomotic anterolateral thigh flaps.</p><p><b>METHODS</b>Twenty-six consecutive free anterolateral thigh flaps in 26 patients were transplanted for repairing widespread defects of traumatic soft tissue in heel from October 1997 to March 2005, suturing the descending branch of the lateral circumflex femoral vascular and posterior tibial vascular to reconstruct the blood supply of transplanted flaps, repairing lateral femoral cutaneous nerve to recover their sensation, fixing tensor fasciae in the calcaneum to add their stabilization.</p><p><b>RESULTS</b>All flaps survived completely,the wounds healed in the initial treatment, follow up 3 to 48 months, twenty-six cases achieved partial sensation, good contour and stabilization.</p><p><b>CONCLUSIONS</b>The anterolateral thigh flap is an ideal flap for repairing widespread defects of traumatic soft tissue in heel, because it has such advantages as adequate blood supply, big dermatosis area and covert donor site, furthermore, nervi cutaneous femoris lateralis and tensor fasciae offer the good sensation and adequate stabilization.</p>
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Adult , Female , Humans , Male , Middle Aged , Young Adult , Heel , Wounds and Injuries , Plastic Surgery Procedures , Skin Transplantation , Soft Tissue Injuries , General Surgery , Surgical Flaps , Thigh , General SurgeryABSTRACT
The low-production is a ubiquitous problem and has prevented the commercialization of secondary metabolite production in plant cell culture. In order to examine the effective approaches to improvement of secondary metabolite production in plant cell culture, the investigation of anthocyanins accumulation in suspension cultures of Vitis vinifera, as a model system, had been initiated in our laboratory. In this present research, various elicitors and the precursor of phenylalanine were used in combination to enhance the anthocyanins production in suspension cultures of Vitis vinifera. And an integrated process with the combination of elicitation, precursor feeding and light irradiation was reported for rational bioprocess design. Among the combination treatment of phenylalanine feeding and several elicitors (methyl-beta-cyclodextrin, dextran T-40, methyl jasmonate, extracts of Aspergillus niger and Fusarium orthoceras), the combination with methyl jasmonate gave the highest anthocyanins production in suspension cultures of Vitis vinifera. When compared to the controls, the anthocyanins content (CV/g, FCW) and production (CV/L) increased by 2.7-fold and 3.4-fold, respectively. The optimum time for the addition of phenylalanine and methyl jasmonate was 4 days after inoculation. Two cell lines with different anthocyanins-producing capacity responded differently to the optimum combination treatment of 30 micromol/L phenylalanine feeding, 218 micromol/L methyl jasmonate elicitation and 3000 to approximately 4000 1x light illumination. The high-and low-anthocyanins-producing cell lines of VV05 and VV06 produced the maximum of 2975 and 4090 CV/L of anthocyanins that were 2.5- and 5.2-fold of the controls, respectively.
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Acetates , Pharmacology , Anthocyanins , Cell Culture Techniques , Methods , Cells, Cultured , Culture Media , Cyclopentanes , Pharmacology , Light , Oxylipins , Pharmacology , Phenylalanine , Pharmacology , Vitis , Cell Biology , MetabolismABSTRACT
Embryonic stem (ES) cells are pluripotent cells capable of extensive proliferation while maintaining their potential to differentiate into any cell type in the body. ES cells can therefore be considered a renewable source of therapeutically useful cells. While ES-derived cells have tremendous potential in many experimental and therapeutic applications, the scope of their utility is dependent on the availability of relevant cell quantities. Therefore, most of the researches are being focused on the differentiation of ES cells. ES cell aggregation is important for embryoid body (EB) formation and the subsequent generation of ES cell derivatives. EB has been shown to recapitulate aspect of early embryogenesis, including the formation of a complex three-dimensional architecture wherein cell-cell and cell-matrix interactions are thought to support the development of the three embryonic germ layers and their derivatives. Standard methods of EB formation include hanging drop and liquid suspension culture. Both culture systems maintain a balance between allowing ES cell aggregation necessary for EB formation and preventing EB agglomeration for efficient cell growth and differentiation. However, they are limited in their production capacity. In this paper, we established a new approach for the mass production of EBs in a scalable culture system. The rotary cell culture system (RCCS, STLV type) was adopted to produce EBs. The vessel was placed on its rotary base and the experiment started with a beginning rotation rate of approximately 8 r/min which has been previously determined empirically as the optimal initial speed to yield randomized gravitational vectors while minimizing fluid shear stress. To keep the aggregations pfloating in simulated microgravityq, the rotation rate was increased as the EBs visibly grew. The EB production efficiency was calculated when different cell densities were inoculated. The kinetic change of EBs was measured during the time course of EB formation. Compared with the traditional method of producing EBs with hanging drop, the multi-potential of the resulting EBs in RCCS was analyzed by the capability of cardiomyocyte genesis. The results showed that EBs could be produced by RCCS with high efficiency. The optimal cell density inoculated in RCCS was 10000 cells/ml, in which EB production was about twice higher than that in the suspending culture. Day 4-5 was the optimal time point for harvesting EBs. To clarify whether the differentiated potential of EBs might be affected by the microgravity produced by the rotary cell culture system, cardiogenic induction during ES cell differentiation was evaluated in our study. It was manifested by appearance of spontaneously and rhythmically contracting myocytes. In addition, immuno-histological and RT-PCR detection showed that the harvested EBs in RCCS exhibited the expected cardiac genesis and morphology. So, scalable production of EBs is obtained by RCCS. It will provide a useful approach to generate a large quantity of ES-derived cells for further research or application.
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We undertook a series of studies to evaluate the role of microenvironment during embryonic stem cell (ESC) proliferation and differentiation. In this paper, cell microencapsulation technology was employed, which allows the free exchange of nutrients, oxygen and biologically active products between the entrapped cell and culture medium. We analyzed the feasibility of mouse ESCs in microcapsules and evaluated the growth, metabolic activity and differentiation of ESCs once enclosed in alginate-Ca(2+) microbead, solid or liquefied core alginate-poly-lysine-alginate (APA) microcapsule, respectively. We found that ESCs grew gradually in both types of microcapsules, but the appearance of cells was distinctive for each type of capsule. In the case of unliquefied microcapsules, cells created multiple spherical or lens-shaped aggregates. In contrast, the liquefied alginate core allowed the enclosed ESCs to grow together in a clump at the periphery of the capsule. Combined with cell viability and activity of glucose/lactic acid metabolism, the liquefied core of APA might provide more suitable culture conditions for the ESC growth in comparison with the unliquefied type or alginate-Ca(2+). For better evaluating the nature of ESC growth in APA microcapsules in vitro (that is whether or not encapsulated ESCs maintained undifferentiated state while they kept the ability for proliferation), the expression of the typical markers for undifferentiated, dividing ESCs, such as the stage specific embryonic antigen (SSEA-1) and alkaline phosphatase (AP), was detected by immunochemistry and immunofluorescence staining. The results showed that cell aggregates formed in the microcapsule still expressed the marker proteins at a higher level on day 22 in vitro. The expression of gene Oct-4, a transcription factor necessary for maintaining ESCs in an undifferentiated state, was also detected when RT-PCR assay was employed (on day 22 in vitro). In addition, cell aggregates were released from the microcapsules by mechanical disruption and induced into insulin-producing cells. These findings further indicate that most of the ESCs in APA microcapsule maintain their multi-potential even though the culture time prolonged as long as 22 d in vitro. Taken together, APA microcapsule provides a suitable microenvironment that promotes ESCs to maintain their stemness. Therefore, the microenvironment plays an important role in the process of ESC proliferation and differentiation.