Formulation development and evaluation of gastroretentive floating beads with Brucea javanica oil using ionotropic gelation technology / 中国天然药物

In the present study, a gastric retention floating system for Brucea javanica oil, composed of alginate and carrageenan, was prepared using ionotropic gelation. Parameters for floatability, drug load, encapsulation efficiency, bead morphology, in vitro release, and in vivo gastric retention were evaluated. The optimized formulation via Box-Behnken design consisted of 1.7% alginate (W/V), 1.02% carrageenan (W/V), 1.4% CaCO (W/V), and a gelling bath of pH 0.8. The alginate-carrageenan-Brucea javanica oil beads had a porous structure and exhibited up to 24 h of in vitro floatability with a load capacity of 45%-55% and an encapsulation efficiency of 70%-80%. A 6-h sustained release was observed in vitro. The beads had a prolonged gastric retention (> 60% at 6 h) in fasted rats, compared to non-floating beads (15% at 6 h), as measured by gamma scintigraphy with single-photon emission tomography/computed tomography (SPET/CT). In conclusion, the alginate-carrageenan-Brucea javanica oil system showed enhanced oil encapsulation efficiency, excellent floating and gastric retention abilities, and a favorable release behavior.

Formulation development and evaluation of gastroretentive floating beads with Brucea javanica oil using ionotropic gelation technology / 中国天然药物

In the present study, a gastric retention floating system for Brucea javanica oil, composed of alginate and carrageenan, was prepared using ionotropic gelation. Parameters for floatability, drug load, encapsulation efficiency, bead morphology, in vitro release, and in vivo gastric retention were evaluated. The optimized formulation via Box-Behnken design consisted of 1.7% alginate (W/V), 1.02% carrageenan (W/V), 1.4% CaCO (W/V), and a gelling bath of pH 0.8. The alginate-carrageenan-Brucea javanica oil beads had a porous structure and exhibited up to 24 h of in vitro floatability with a load capacity of 45%-55% and an encapsulation efficiency of 70%-80%. A 6-h sustained release was observed in vitro. The beads had a prolonged gastric retention (> 60% at 6 h) in fasted rats, compared to non-floating beads (15% at 6 h), as measured by gamma scintigraphy with single-photon emission tomography/computed tomography (SPET/CT). In conclusion, the alginate-carrageenan-Brucea javanica oil system showed enhanced oil encapsulation efficiency, excellent floating and gastric retention abilities, and a favorable release behavior.

CD57 (Leu-7, HNK-1) immunoreactivity seen in thin arteries in the human fetal lung / 대한해부학회지

CD57 (synonyms: Leu-7, HNK-1) is a well-known marker of nerve elements including the conductive system of the heart, as well as natural killer cells. In lung specimens from 12 human fetuses at 10–34 weeks of gestation, we have found incidentally that segmental, subsegmental, and more peripheral arteries strongly expressed CD57. Capillaries near developing alveoli were often or sometimes positive. The CD57-positive tissue elements within intrapulmonary arteries seemed to be the endothelium, internal elastic lamina, and smooth muscle layer, which corresponded to tissue positive for a DAKO antibody reactive with smooth muscle actin we used. However, the lobar artery and pulmonary arterial trunk as well as bronchial arteries were negative. Likewise, arteries in and along any abdominal viscera, as well as the heart, thymus, and thyroid, did not express CD57. Thus, the lung-specific CD57 reactivity was not connected with either of an endodermal- or a branchial arch-origin. CD57 antigen is a sugar chain characterized by a sulfated glucuronic acid residue that is likely to exist in some glycosphingolipids. Therefore, a chemical affinity or an interaction might exist between CD57-positive arterioles and glycosphingolipids originating from alveoli, resulting in acceleration of capillary budding to make contact with the alveolar wall. CD57 might therefore be a functional marker of the developing air-blood interface that characterizes the fetal lung at the canalicular stage.

Alveolar bone repair with strontium- containing nanostructured carbonated hydroxyapatite

ABSTRACT Objective: This study aimed to evaluate bone repair in rat dental sockets after implanting nanostructured carbonated hydroxyapatite/sodium alginate (CHA) and nanostructured carbonated hydroxyapatite/sodium alginate containing 5% strontium microspheres (SrCHA) as bone substitute materials. Methods: Twenty male Wistar rats were randomly divided into two experimental groups: CHA and SrCHA (n=5/period/group). After one and 6 weeks of extraction of the right maxillary central incisor and biomaterial implantation, 5 μm bone blocks were obtained for histomorphometric evaluation. The parameters evaluated were remaining biomaterial, loose connective tissue and newly formed bone in a standard area. Statistical analysis was performed by Mann-Withney and and Wilcoxon tests at 95% level of significance. Results: The histomorphometric results showed that the microspheres showed similar fragmentation and bio-absorbation (p>0.05). We observed the formation of new bones in both groups during the same experimental periods; however, the new bone formation differed significantly between the weeks 1 and 6 (p=0.0039) in both groups. Conclusion: The CHA and SrCHA biomaterials were biocompatible, osteoconductive and bioabsorbable, indicating their great potential for clinical use as bone substitutes.

Immobilization of ammonia-oxidizing bacteria by polyvinyl alcohol and sodium alginate

Abstract Ammonia-oxidizing bacteria were immobilized by polyvinyl alcohol (PVA) and sodium alginate. The immobilization conditions and ammonia oxidation ability of the immobilized bacteria were investigated. The following immobilization conditions were observed to be optimal: PVA, 12%; sodium alginate, 1.1%; calcium chloride, 1.0%; inoculum concentration, 1.3 immobilized balls/mL of immobilized medium; pH, 10; and temperature, 30 °C. The immobilized ammonia-oxidizing bacteria exhibited strong ammonia oxidation ability even after being recycled four times. The ammonia nitrogen removal rate of the immobilized ammonia-oxidizing bacteria reached 90.30% under the optimal immobilization conditions. When compared with ammonia-oxidizing bacteria immobilized by sodium alginate alone, the bacteria immobilized by PVA and sodium alginate were superior with respect to pH resistance, the number of reuses, material cost, heat resistance, and ammonia oxidation ability.

Volatile metabolites produced from agro-industrial wastes by Na-alginate entrapped Kluyveromyces marxianus

Abstract The aim of this study was to evaluate the effects of alginate entrapment on fermentation metabolites of Kluyveromyces marxianus grown in agrowastes that served as the liquid culture media. K. marxianus cells entrapped in Na-alginate were prepared using the traditional liquid-droplet-forming method. Whey and pomaces from processed tomatoes, peppers, and grapes were used as the culture media. The changes in the concentrations of sugar, alcohol, organic acids, and flavor compounds were analyzed using gas chromatography-mass spectrometry (GC-MS) and high pressure liquid chromatography (HPLC). Both free and entrapped, K. marxianus were used individually to metabolize sugars, organic acids, alcohols, and flavor compounds in the tomato, pepper, grape, and acid whey based media. Marked changes in the fermentation behaviors of entrapped and free K. marxianus were observed in each culture. A 1.45-log increase was observed in the cell numbers of free K. marxianus during fermentation. On the contrary, the cell numbers of entrapped K. marxianus remained the same. Both free and entrapped K. marxianus brought about the fermentation of sugars such as glucose, fructose, and lactose in the agrowaste cultures. The highest volume of ethanol was produced by K. marxianus in the whey based media. The concentrations of flavor compounds such as ethyl acetate, isoamyl alcohol, isoamyl acetate, 2-phenylethyl isobutyrate, phenylethyl acetate, and phenylethyl alcohol were higher in fermented agrowaste based media compared to the control.

Effect of shift rotation culture on formation and activity of encapsulated hepatocytes aggregates / 浙江大学学报·医学版

To observe the effect of uniform and shift rotation culture on the formation and activity of the alginate-chitosan (AC) microencapsulated HepLL immortalized human hepatocytes and HepG2 cells aggregates.AC microcapsulated HepG2 and HepLL cells were randomly divided into two groups. Each group was divided into 3 subgroups according to uniform and shift rotation culture.The size and number of aggregates were observed and measured under laser confocal microscopy and inverted microscope dynamically. The amount of albumin synthesis was detected by ELISA, the clearance of ammonia was detected by colorimetry, and diazepam conversion function was detected by high performance liquid chromatography (HPLC).On day 6, 8, 10, 12, 14 and 16, the number and size of the aggregates, albumin synthesis, diazepam clearance and ammonium clearance increased significantly in shift rotation culture group than in uniform group (all<0.01). The albumin synthesis, diazepam clearance, and ammonium clearance in the microencapsulated HepLL groups were significantly higher than those of HepG2 cells at any time (all<0.01).Shift rotation culture can significantly promote the formation and increase the activity of AC microencapsulated HepLL and HepG2 aggregates, and HepLL cells may be more suitable for bioartificial liver than HepG2.

Cytocompatibility and biocompatibility of nanostructured carbonated hydroxyapatite spheres for bone repair

ABSTRACT Objective The aim of this study was to investigate the in vitro and in vivo biological responses to nanostructured carbonated hydroxyapatite/calcium alginate (CHA) microspheres used for alveolar bone repair, compared to sintered hydroxyapatite (HA). Material and Methods The maxillary central incisors of 45 Wistar rats were extracted, and the dental sockets were filled with HA, CHA, and blood clot (control group) (n=5/period/group). After 7, 21 and 42 days, the samples of bone with the biomaterials were obtained for histological and histomorphometric analysis, and the plasma levels of RANKL and OPG were determined via immunoassay. Statistical analysis was performed by Two-Way ANOVA with post-hoc Tukey test at 95% level of significance. Results The CHA and HA microspheres were cytocompatible with both human and murine cells on an in vitro assay. Histological analysis showed the time-dependent increase of newly formed bone in control group characterized by an intense osteoblast activity. In HA and CHA groups, the presence of a slight granulation reaction around the spheres was observed after seven days, which was reduced by the 42nd day. A considerable amount of newly formed bone was observed surrounding the CHA spheres and the biomaterials particles at 42-day time point compared with HA. Histomorphometric analysis showed a significant increase of newly formed bone in CHA group compared with HA after 21 and 42 days from surgery, moreover, CHA showed almost 2-fold greater biosorption than HA at 42 days (two-way ANOVA, p<0.05) indicating greater biosorption. An increase in the RANKL/OPG ratio was observed in the CHA group on the 7th day. Conclusion CHA spheres were osteoconductive and presented earlier biosorption, inducing early increases in the levels of proteins involved in resorption.

Biodegradation of cypermethrin by immobilized cells of Micrococcus sp. strain CPN 1

Pyrethroid pesticide cypermethrin is a environmental pollutant because of its widespread use, toxicity and persistence. Biodegradation of such chemicals by microorganisms may provide an cost-effective method for their detoxification. We have investigated the degradation of cypermethrin by immobilized cells of Micrococcus sp. strain CPN 1 in various matrices such as, polyurethane foam (PUF), polyacrylamide, sodium alginate and agar. The optimum temperature and pH for the degradation of cypermethrin by immobilized cells of Micrococcus sp. were found to be 30 °C and 7.0, respectively. The rate of degradation of 10 and 20 mM of cypermethrin by freely suspended cells were compared with that of immobilized cells in batches and semi-continuous with shaken cultures. PUF-immobilized cells showed higher degradation of cypermethrin (10 mM and 20 mM) than freely suspended cells and cells immobilized in other matrices. The PUF-immobilized cells of Micrococcus sp. strain CPN 1 were retain their degradation capacity. Thus, they can be reused for more than 32 cycles, without losing their degradation capacity. Hence, the PUF-immobilized cells of Micrococcus sp. could potentially be used in the bioremediation of cypermethrin contaminated water.

Increased circulating macrophage migration inhibitory factor levels are associated with coronary artery disease

BACKGROUND: To evaluate the macrophage migration inhibitory factor and E-selectin levels in patients with acute coronary syndrome. MATERIALS/METHODS: We examined the plasma migration inhibitory factor and E-selectin levels in 87 patients who presented with chest pain at our hospital. The patients were classified into two groups according to their cardiac status. Sixty-five patients had acute myocardial infarction, and 22 patients had non-cardiac chest pain (non-coronary disease). We designated the latter group of patients as the control group. The patients who presented with acute myocardial infarction were further divided into two subgroups: ST-elevated myocardial infarction (n = 30) and non-ST elevated myocardial infarction (n = 35). RESULTS: We found higher plasma migration inhibitory factor levels in both acute myocardial infarction subgroups than in the control group. However, the E-selectin levels were similar between the acute myocardial infarction and control patients. In addition, we did not find a significant difference in the plasma migration inhibitory factor levels between the ST elevated myocardial infarction and NST-elevated myocardial infarction subgroups. DISCUSSION: The circulating concentrations of migration inhibitory factor were significantly increased in acute myocardial infarction patients, whereas the soluble E-selectin levels were similar between acute myocardial infarction patients and control subjects. Our results suggest that migration inhibitory factor may play a role in the atherosclerotic process. .

Therapeutic Options in Idiopathic Burning Mouth Syndrome: Literature Review

Introduction Burning mouth syndrome (BMS) is characterized by a burning sensation in the tongue, palate, lips, or gums of no well-defined etiology. The diagnosis and treatment for primary BMS are controversial. No specific laboratory tests or diagnostic criteria are well established, and the diagnosis is made by excluding all other possible disorders. Objective To review the literature on the main treatment options in idiopathic BMS and compare the best results of the main studies in 15 years. Data Synthesis We conducted a literature review on PubMed/MEDLINE, SciELO, and Cochrane-BIREME of work in the past 15 years, and only selected studies comparing different therapeutic options in idiopathic BMS, with preference for randomized and double-blind controlled studies. Final Comments Topical clonazepam showed good short-term results for the relief of pain, although this was not presented as a definitive cure. Similarly, α-lipoic acid showed good results, but there are few randomized controlled studies that showed the longterm results and complete remission of symptoms. On the other hand, cognitive therapy is reported as a good and lasting therapeutic option with the advantage of not having side effects, and it can be combined with pharmacologic therapy. .

Three-dimensional Culture of Chondrocyte Using Methacrylic Alginate Gel Beads Cross-linked with Mixed Metal-cation / 生物医学工程学杂志

This study was to explore a better three-dimensional (3-D) culture method of chondrocyte. The interpenetrating network (IPN) gel beads were developed through a photo-cross linking reaction with mixed barium ions and calcium ions at the ratio of 5:5 with the methacrylic alginate (MA), which was a chemically conjugated alginate with methacrylic groups. The second generation of primary cartilage cells was encapsulated in the MA gel beads for three weeks. In the designated timing, HE stain, Alamar blue method and Scanning electron microscopic were used to determine the cartilage cells growth, proliferation and the cell distribution in the scaffolds, respectively. The expression of type II collagen was investigated by an immunohistochemistry assay and the glycosaminoglycan content was quantitatively evaluated with the spectrophotometry of 1, 9 dimethylene blue assay. Compared to the alginate control group, the deposition of glycosaminoglycan was significantly upregulated in IPN-MA gel beads with higher cell proliferation. The secretion of extracellular matrix and proliferation of chondrocyte in methacrylic alginate gel beads were higher than that in Alginate beads. Cells were able to attach, to grow well on the scaffolds under scanning electron microscopy. The result of immunohistochemistry staining of collagen type II was positive, confirming the maintenance of chondrocyte phenotype in methacrylic alginate gel beads. This study shows a great potential for three-dimensional culture of cartilage.

Glucan HBP-A increase type II collagen expression of chondrocytes in vitro and tissue engineered cartilage in vivo / 中国结合医学杂志

<p><b>OBJECTIVE</b>Although chondroprotective activities have been documented for polysaccharides, the potential target of different polysaccharide may differ. The study was aimed to explore the effect of glucan HBP-A in chondrocyte monolayer culture and chondrocytes-alginate hydrogel constructs in vivo, especially on the expression of type II collagen.</p><p><b>METHODS</b>Chondrocytes isolated from rabbit articular cartilage were cultured and verified by immunocytochemical staining of type II collagen. Chondrocyte viability was assessed after being treated with HBP-A in different concentrations. Morphological status of chondrocytes-alginate hydrogel constructs in vitro was observed by scanning electron microscope (SEM). The constructs were treated with HBP-A and then injected to nude mice subcutaneously. Six weeks after transplantation, the specimens were observed through transmission electron microscopy (TEM). The mRNA expressions of disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTs-5), aggrecan and type II collagen in both monolayer culture and constructs were determined by real time polymerase chain reaction (PCR). The expression of type II collagen and matrix metalloproteinases-3 (MMP-3) in chondrocyte monolayer culture was also tested through Western blot and enzyme linked immunosorbent assay (ELISA), respectively.</p><p><b>RESULTS</b>MMP-3 secretion and ADAMTs-5 mRNA expression in vitro were inhibited by HBP-A at 0.3 mg/mL concentration. In morphological study, there were significant appearance of collagen in those constructs treated by HBP-A. Accordingly, in both chondrocyte monolayer culture and chondrocytes-alginate hydrogel constructs, the expression of type II collagen was increased significantly in HBP-A group when compared with control group (P<0.001).</p><p><b>CONCLUSIONS</b>The study documented that the potential pharmacological target of glucan HBP-A in chondrocytes monolayer culture and tissue engineered cartilage in vivo may be concerned with the inhibition of catabolic enzymes MMP-3, ADAMTs-5, and increasing of type II collagen expression.</p>

Non-small cell lung cancer 95D cells co-cultured with 3D-bioprinted scaffold to construct a lung cancer model in vitro / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To fabricate an innovative scaffold for lung cancer cell culture and establish a three-dimensional lung cancer model in vitro, and to reveal the differences in biological functions of lung cancer cells under the two-dimensional and three-dimensional culture conditions.</p><p><b>METHODS</b>We chose agarose and alginate as the scaffold materials, and 3D printing technique was applied to construct cell culture scaffold. 95D cells were co-cultured with this scaffold. The differences of cell morphology, proliferation ability, protein expression, etc. in the cells cultured under 2D and 3D cultural conditions were evaluated by light microscopy using HE staining, MTT assay, scanning electron microscopy, and Western blot analysis.</p><p><b>RESULTS</b>Cells cultured in 2D wells displayed a spindle and polygonal morphology, whereas those grown in the 3D culture aggregated into spheroids, which invaded, migrated and disseminated into the surrounding scaffold. MTT assay showed that the proliferation rates of the 3D-cultured cells for 2-6 days were significantly lower than, but those cultured for 8-9 days were significantly higher than that of the 2D-cultured cells, indicating that proliferative activity of the cells grown in 2D cultures for 8-9 days was inhibited. In contrast, cells grown on 3D scaffolds still maintained a higher proliferation. The Western blot assay showed that the expression of Cdc42, p53, mTOR were significantly down-regulated in 3D scaffold-cultured group (0.529±0.103, 0.820±0.038 vs. 1.967±0.066), compared with that of the 2D-cultured group (3.063±0.139, 1.738±0.122 vs. 2.472±0.151) (P<0.05 for all), while the expression of MMP-2 was up-regulated in the 3D-cultured cells (1.110±0.029), significantly higher than that of the 2D-cultured cells (0.017±0.001) (P<0.05).</p><p><b>CONCLUSIONS</b>The cell morphology, proliferation and associated protein expression of lung cancer cells in 3D-culture systems are distinctively different as compared to those of the 2D-cultural cells. 3D-bioprinted agarose-alginate scaffold can better mimic the growth microenvironment of lung cancer in vivo and may provide a promising model for lung cancer research in vitro.</p>

Puncture Point Hemostatic Effect Observation of Different Materials with Modified Seldinger Technique in PICC Catheter / 中国医疗器械杂志

<p><b>OBJECTIVE</b>To explore the improvement the dingle technology through the PICC catheter puncture point elbow hemostatic effect. Selection.</p><p><b>METHODS</b>Between January 2013 and December 2013, chest hospital affiliated to Shanghai jiaotong university under the guidance of ultrasound improved the Ding Gehang PICC catheter patients of 997 cases were randomly divided into three groups A, B, C, respectively, using gauze pad, calcium alginate wound dressings, calcium alginate wound dressings with hemostatic gauze pad three methods to puncture point, compare the three groups within 48 h after puncture biopsy in patients with some local bleeding, treatment times and catheter after 1 week of the maintenance costs of the catheter.</p><p><b>RESULTS</b>Compared with A, B two groups, patients of group C tube after 48 hours the puncture point local oppression hemostasis effect is better than that of group A and B, the difference was statistically significant (all P < 0.05); Catheter maintenance: group C within 1 week after catheter tube after local lowest maintenance cost.</p><p><b>CONCLUSION</b>PICC for surgery after the puncture point of oppression hemostasis method choice, the effect of calcium alginate dressings hemostatic gauze pad is better than that of gauze pads and calcium alginate dressings, calcium alginate dressings and gauze pad is more effective and economic, in clinical use.</p>

Cranial vault reconstruction with bone morphogenetic protein, calcium phosphate, acellular dermal matrix, and calcium alginate in mice

PURPOSE: To evaluate experimental cranial vault reconstructions, by combining bone morphogenetic protein type 2 (BMP-2) and different matrices. METHODS: Fourty-nine animals were initially included (seven per group). We designed an experimental, open, prospective and comparative study, divided in seven groups: 1 - BMP-2+calcium phosphate (BT); 2 - BMP-2+acellular dermal matrix (BM); 3 - BMP-2+calcium alginate (BA); 4 - TCP; 5 - MDM; 6 - ALG; 7 - Bone autograft (BAG). A bone failure was created in left parietal bone of adult male mice. At the same procedure reconstruction was performed. After five weeks, animals were sacrificed, and reconstruction area was removed to histological analysis. After exclusion due to death or infection, thirty-eight animals were evaluated (BT=5; BM=6; BA=6; TCP=7; MDM=3; ALG=6; BAG=5). RESULTS: A higher incidence of infection has occurred in MDM group (57%, P=0.037). In cortical fusion, groups BAG, TCP, and BMP-2+TCP (BT) obtained the best scores, comparing to the others (P=0.00846). In new bone formation, groups BT, BAG, and TCP have presented the best scores (P=0.00835). When neovascularization was considered, best groups were BMP-2+MDM (BM), BMP-2+ALG (BA), TCP, and MDM (P=0.001695). BAG group was the best in bone marrow formation, followed by groups BT and TCP (P=0.008317). CONCLUSIONS: Bone morphogenetic protein type 2 increased bone regeneration in experimental skull reconstruction, especially when combined to calcium phosphate. Such association was even comparable to bone autograft, the gold-standard treatment, in some histological criteria. .

A simple technique for tracking individual spore and gametophyte development in Adiantum lunulatum Burm. f. using modified extra thin alginate film technique.

A new technique was developed for accurate calculation of percent germination and tracking of individual spores from germination to gametophyte development in Adiantum lunulatum. High percentage of ETAF immobilized spore germination (72.4%) was followed by development of gametophytic clumps. The ETAF immobilized clumps were cut into pieces and multiplied en masse. Apomictic sporophytes developed from the gametophytes. This indicated the potential of ETAF for mass propagation of A. lunulatum without the need to start from spores. Since individual spores can be tracked from germination to gametophyte development, the ETAF technique has the potential to be used for (i) harvesting uniformly developed plants of similar age for extensive experimentations and commercial utilization and (ii) detailed study on developmental and reproductive biology of different ferns and fern allies.

Differentiation of adipose-derived stem cells toward nucleus pulposus-like cells induced by hypoxia and a three-dimensional chitosan-alginate gel scaffold in vitro / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Injectable three-dimensional (3D) scaffolds have the advantages of fluidity and moldability to fill irregular-shaped defects, simple incorporation of bioactive factors, and limited surgical invasiveness. Adipose-derived stem cells (ADSCs) are multipotent and can be differentiated toward nucleus pulposus (NP)-like cells. A hypoxic environment may be important for differentiation to NP-like cells because the intervertebral disc is an avascular tissue. Hence, we investigated the induction effects of hypoxia and an injectable 3D chitosan-alginate (C/A) gel scaffold on ADSCs.</p><p><b>METHODS</b>The C/A gel scaffold consisted of medical-grade chitosan and alginate. Gel porosity was calculated by liquid displacement method. Pore microstructure was analyzed by light and scanning electron microscopy. ADSCs were isolated and cultured by conventional methods. Passage 2 BrdU-labeled ADSCs were co-cultured with the C/A gel. ADSCs were divided into three groups (control, normoxia-induced, and hypoxia-induced groups). In the control group, cells were cultured in 10% FBS/DMEM. Hypoxia-induced and normoxia-induced groups were induced by adding transforming growth factor-β1, dexamethasone, vitamin C, sodium pyruvate, proline, bone morphogenetic protein-7, and 1% ITS-plus to the culture medium and maintaining in 2% and 20% O2, respectively. Histological and morphological changes were observed by light and electron microscopy. ADSCs were characterized by flow cytometry. Cell viability was investigated by BrdU incorporation. Proteoglycan and type II collagen were measured by safranin O staining and the Sircol method, respectively. mRNA expression of hypoxia-inducing factor-1α (HIF-1α), aggrecan, and Type II collagen was determined by reverse transcription-polymerase chain reaction.</p><p><b>RESULTS</b>C/A gels had porous exterior surfaces with 80.57% porosity and 50-200 üm pore size. Flow cytometric analysis of passage 2 rabbit ADSCs showed high CD90 expression, while CD45 expression was very low. The morphology of induced ADSCs resembled that of NP cells. BrdU immunofluorescence showed that most ADSCs survived and proliferated in the C/A gel scaffold. Scanning electron microscopy showed that ADSCs grew well in the C/A gel scaffold. ADSCs in the C/A gel scaffold were positive for safranin O staining. Hypoxia-induced and normoxia-induced groups produced more proteoglycan and Type II collagen than the control group (P < 0.05). Proteoglycan and Type II collagen levels in the hypoxia-induced group were higher than those in the normoxia-induced group (P < 0.05). Compared with the control group, higher mRNA expression of HIF-1α, aggrecan, and Type II collagen was detected in hypoxia-induced and normoxiainduced groups (P < 0.05). Expression of these genes in the hypoxia-induced group was significantly higher than that in the normoxia-induced group (P < 0.05).</p><p><b>CONCLUSION</b>ADSCs grow well in C/A gel scaffolds and differentiate toward NP-like cells that produce the same extracellular matrix as that of NP cells under certain induction conditions, which is promoted in a hypoxic state.</p>

Preparation of sodium alginate-nanohydroxyapatite composite material for bone repair and its biocompatibility / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To prepare sodium alginate-nanohydroxyapatite composite material and to explore its feasibility as a bone repair material.</p><p><b>METHODS</b>Sodium alginate-nanohydroxyapatite composite material was prepared using chemical cross-linking and freeze-drying technology. The composite was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM) and its porosity was measured by liquid displacement method. The fifth passage of bone marrow stromal stem cells (BMSCs) were incubated on the composite material and then growth was observed by inverted microscope and SEM. BMSCs were cultured with liquid extracts of the material, methyl thiazolyl tetrazolium (MTT) assay was used to calculate the relative growth rate (RGR) on 1, 3, 5 d and to evaluate the cytotoxicity. Fresh dog blood was added into the liquid extracts to conduct hemolysis test, the spectrophotometer was used to determine the optical density (OD) and to calculate the hemolysis rate.</p><p><b>RESULTS</b>Sodium alginate-nanohydroxyapatite composite material displayed porosity, the porous pore rate was (88.6 +/- 4.5)%. BMSCs showed full stretching and vigorous growth under inverted microscope and SEM. BMSCs cultured with liquid extracts of the material had good activities. The toxicity of composite material was graded as 1. Hemolysis test results showed that the hemolysis rate of the composite material was 1.28%, thus meeting the requirement of medical biomaterials.</p><p><b>CONCLUSION</b>The composite material fabricated in this study has high porosity and good biocompatibility.</p>

Research on the treatment of liver failure rats with transplantation of alginate microencapsulated hepatocytes in vivo based on poly-ornithine / 生物医学工程学杂志

This study aims to explore the effects of alginate-poly ornithine-alginate (A-PLO-A) and barium alginate-poly ornithine-alginate (B-PLO-A) microcapsules as cells carriers during implantation. Mice hepatocytes coated in A-PLO-A and B-PLO-A microcapsules were implanted into rats with acute liver failure caused by intraperitoneal injection of D-galactosamine. The rat survival rate, liver cell growth, proliferation and metabolism within the microcapsules were investigated, as well as its effect on the improvement of rat acute liver failure. The influence of A-PLO-A-free microcapsules, B-PLO-A-free microcapsules, isolated liver cells, A-PLO-A microcapsule-coated and B-PLO-A microcapsule-coated liver cells was studied. It was found that the chemical-free microcapsules showed no positive effect on the rats with liver failures, with a death rate of 100% in both groups 3 days after the implantation. The ALT, AST and ALB levels were all improved in the isolated liver cell group, the A-PLO-A microcapsule-coated and the B-PLO-A microcapsule-coated groups. The survival rate of both microcapsule-coated liver cell groups was significantly higher than that of the chemical-free microcapsule group and the isolated liver cells group. The microcapsules were retrieved after 4 weeks' implantation, which were observed to be smooth with no cells attaching to the surface. No apparent fibrosis was observed. This research demonstrated the physical stability and the biocompatibility of the PLO-based alginate microcapsules and therefore they could be used as liver cell carriers during implantation.