Establishment and validation of a predictive model of recurrence in primary hepatocellular carcinoma after resection.

Background: In recent years, nomogram prediction models have been widely used to evaluate the prognosis of various diseases. However, studies in primary hepatocellular carcinoma (HCC) are limited. This study sought to explore the risk factors of recurrence of patients with primary HCC after surgical resection and establish a nomogram prediction model. Methods: The data of 424 patients with primary HCC who had been admitted to the Wuhan Third Hospital were retrospectively collected. The patients were followed-up for 5 years after surgery. The patients were divided into the recurrence group (n=189) and control group (n=235) according to whether the cancer recurred after surgery. The differences in the clinical characteristics between the two groups were analyzed. The risk factors of recurrence after surgical resection of primary HCC were also analyzed, and a prediction model was then established using R4.0.3 statistical software. Results: There were significant statistical differences between the two groups in terms of the tumor size, systemic immune-inflammation (SII) index, the number of lesions, tumor differentiation degree, ascites, vascular invasion, and portal vein tumor thrombus (P<0.05). The multivariate regression analysis showed that multiple foci, poorly differentiated tumors, ascites, vascular invasion, and portal vein tumor thrombus were risk factors for the recurrence of primary HCC in patients after surgical resection (P<0.05). The data set was randomly divided into a training set and verification set. The sample size of the training set was 297, and the sample size of the verification set was 127. The area under the receiver operating characteristic (ROC) curve of the training set was 0.866 [95% confidence interval (CI): 0.824-0.907], and the area under the ROC curve of the validation set was 0.812 (95% CI: 0.734-0.890). The Hosmer-Lemeshow Goodness-of-Fit Test was used to test the model with the validation set (χ2=11.243, P=0.188), which indicated that the model had high value in predicting the recurrence of primary HCC after surgical resection. Conclusions: This model had high value in predicting the recurrence of primary HCC in patients after surgical resection. This model could assist clinicians to assess the prognosis of patients. Intensive treatment for high-risk patients might improve the prognosis of patients.

Dietary intervention preserves ß cell function in mice through CTCF-mediated transcriptional reprogramming.

Pancreatic ß cell plasticity is the primary determinant of disease progression and remission of type 2 diabetes (T2D). However, the dynamic nature of ß cell adaptation remains elusive. Here, we establish a mouse model exhibiting the compensation-to-decompensation adaptation of ß cell function in response to increasing duration of high-fat diet (HFD) feeding. Comprehensive islet functional and transcriptome analyses reveal a dynamic orchestration of transcriptional networks featuring temporal alteration of chromatin remodeling. Interestingly, prediabetic dietary intervention completely rescues ß cell dysfunction, accompanied by a remarkable reversal of HFD-induced reprogramming of islet chromatin accessibility and transcriptome. Mechanistically, ATAC-based motif analysis identifies CTCF as the top candidate driving dietary intervention-induced preservation of ß cell function. CTCF expression is markedly decreased in ß cells from obese and diabetic mice and humans. Both dietary intervention and AAV-mediated restoration of CTCF expression ameliorate ß cell dysfunction ex vivo and in vivo, through transducing the lipid toxicity and inflammatory signals to transcriptional reprogramming of genes critical for ß cell glucose metabolism and stress response.

Human expandable pancreatic progenitor-derived ß cells ameliorate diabetes.

An unlimited source of human pancreatic ß cells is in high demand. Even with recent advances in pancreatic differentiation from human pluripotent stem cells, major hurdles remain in large-scale and cost-effective production of functional ß cells. Here, through chemical screening, we demonstrate that the bromodomain and extraterminal domain (BET) inhibitor I-BET151 can robustly promote the expansion of PDX1+NKX6.1+ pancreatic progenitors (PPs). These expandable PPs (ePPs) maintain pancreatic progenitor cell status in the long term and can efficiently differentiate into functional pancreatic ß (ePP-ß) cells. Notably, transplantation of ePP-ß cells rapidly ameliorated diabetes in mice, suggesting strong potential for cell replacement therapy. Mechanistically, I-BET151 activates Notch signaling and promotes the expression of key PP-associated genes, underscoring the importance of epigenetic and transcriptional modulations for lineage-specific progenitor self-renewal. In summary, our studies achieve the long-term goal of robust expansion of PPs and represent a substantial step toward unlimited supplies of functional ß cells for biomedical research and regenerative medicine.

Inguinal Subcutaneous White Adipose Tissue (ISWAT) Transplantation Model of Murine Islets.

Pancreatic islet transplantation is a well-established therapeutic treatment for type 1 diabetes. The kidney capsule is the most commonly used site for islet transplantation in rodent models. However, the tight kidney capsule limits the transplantation of sufficient islets in large animals and humans. The inguinal subcutaneous white adipose tissue (ISWAT), a new subcutaneous space, was found to be a potentially valuable site for islet transplantation. This site has better blood supply than other subcutaneous spaces. Moreover, the ISWAT accommodates a larger islet mass than the kidney capsule, and transplantation into it is simple. This manuscript describes the procedure of mouse islet isolation and transplantation in the ISWAT site of syngeneic diabetic mouse recipients. Using this protocol, murine pancreatic islets were isolated by standard collagenase digestion and a basement membrane matrix hydrogel was used for fixing the purified islets in the ISWAT site. The blood glucose levels of the recipient mice were monitored for more than 100 days. Islet grafts were retrieved at day 100 after transplantation for histological analysis. The protocol for islet transplantation in the ISWAT site described in this manuscript is simple and effective.

JNK-IN-8, a c-Jun N-terminal kinase inhibitor, improves functional recovery through suppressing neuroinflammation in ischemic stroke.

C-Jun N-terminal kinase (JNK) is a pivotal MAPK (mitogen-activated protein kinase), which activated by ischemia brain injury and plays a fairly crucial function in cerebral ischemic injury. Emerging studies demonstrated that JNK-IN-8 (a JNK inhibitor with high specificity) regulates traumatic brain injury through controlling neuronal apoptosis and inflammation. However, the function of JNK-IN-8 in ischemic stroke and the mechanisms underlying of JNK-IN-8 about neuroprotection are not well understood. In this work, male rats were treated with JNK-IN-8 after transient middle cerebral artery occlusion, and then the modified improved neurological function score (mNSS), the foot-fault test (FFT), interleukin-1ß (IL-1ß), IL-6, and tumor necrosis factor-α (TNF-α) levels were assessed. We found that JNK-IN-8-treated rats with MCAO exerted an observable melioration in space learning as tested by the improved mNSS, and showed sensorimotor functional recovery as measured by the FFT. JNK-IN-8 also played anti-inflammatory roles as indicated through decreased activation of microglia and decreased IL-6, IL-1ß, and TNF-α expression. Furthermore, JNK-IN-8 suppressed the activation of JNK and nuclear factor-κB (NF-κB) signaling as indicated by the decreased level of phosphorylated-JNK and p65. All data demonstrate that JNK-IN-8 inhibits neuroinflammation and improved neurological function by inhibiting JNK/NF-κB and is a promising agent for the prevention of ischemic brain injury.

A Method for Islet Transplantation to the Omentum in Mouse.

Islet transplantation has been proposed to be a potential treatment for type 1 diabetes. Recent compelling evidence indicates that intravascular islet infusion is far from ideal and therefore, the omentum is re-emerging as a potentially valuable site for islet transplantation. This experiment requires the isolation of high quality islets and the implantation of the islets to the diabetic recipients. Transplantation to the omentum requires surgical steps that can be better demonstrated visually. Here, the detailed steps for this procedure are presented. Two methods of mixing the isolated islets with hydrogel before placing the mixture into the omental pouch of diabetic mice are described here. Different hydrogels are used for the different conditions. Blood glucose levels of diabetic mouse recipients of syngeneic islets in the omentum were monitored for up to 35 days. Some animals were sacrificed after 14 days to perform immuno-histochemical analysis. This pre-clinical transplantation approach can be used as preliminary data leading up to translation to clinical transplantation.

Using Recombinant Human Collagen With Basic Fibroblast Growth Factor to Provide a Simulated Extracellular Matrix Microenvironment for the Revascularization and Attachment of Islets to the Transplantation Region.

Islet transplantation is considered a potential therapeutic option to reverse diabetes. The pancreatic basement membrane contains a variety of extracellular matrix (ECM) proteins. The abundant ECM is essential for the survival of transplanted islets. However, the ECM proteins necessary for maintaining islet vascularization and innervation are impaired by enzymatic digestion in the isolation process before islet transplantation, leading to destruction of islet microvessels. These are the primary concern and major barrier for long-term islet survival and function. Thus, it is crucial to create an appropriate microenvironment for improving revascularization and islet function to achieve better transplantation outcome. Given the importance of the presence of ECM proteins for islets, we introduce recombinant human collagen (RHC) to construct a simulated ECM microenvironment. To accelerate revascularization and reduce islet injury, we add basic fibroblast growth factor (bFGF) to RHC, a growth factor that has been shown to promote angiogenesis. In order to verify the outcome, islets were treated with RHC combination containing bFGF and then implanted into kidney capsule in type 1 diabetic mouse models. After transplantation, 30-day-long monitoring displayed that 16 mg-60 ng RHC-bFGF group could serve as superior transplantation outcome. It reversed the hyperglycemia condition in host rapidly, and the OGTT (oral glucose tolerance test) showed a similar pattern with the control group. Histological assessment showed that 16 mg-60 ng RHC-bFGF group attenuated apoptosis, promoted cellular proliferation, triggered vascularization, and inhibited inflammation reaction. In summary, this work demonstrates that application of 16 mg-60 ng RHC-bFGF and islets composite enhance the islet survival, function, and long-term transplantation efficiency.

Aberrant activation of Notch-1 signaling inhibits podocyte restoration after islet transplantation in a rat model of diabetic nephropathy.

Signaling abnormalities play important roles during podocyte injury and have been indicated as crucial events for triggering many glomerular diseases. There is emerging evidence demonstrating significant improvements in preventing renal injury and restoring podocytes after islet transplantation. However, whether signaling abnormalities affect the therapeutic efficacy of islet transplantation remain unclear. This study was established to investigate the impact of Notch-1 signaling activation on renal injury and podocyte restoration after islet transplantation. Experiments were performed in vivo and in vitro under conditions of diabetic nephropathy and high-glucose medium, respectively. Podocyte injury in vitro was induced by high-glucose concentration, and expression levels of genes associated with the Notch-1 pathway were also regulated by Jagged-1/FC and N-[N-(3,5-Difluorophenacetyl)-L-alanyl]- S-phenylglycine t-butyl ester (DAPT). Podocytes were co-cultured with islets to investigate the protective effect of islets in high-glucose conditions. Histopathological staining and transmission electron microscopy were performed to assess pathological changes in podocytes in glomeruli. The results from this study showed that Notch-1 signaling in podocytes was significantly decreased by functional islet cells in vivo and in vitro. Compared with the co-cultured group and transplanted group, highly activated Notch-1 signaling significantly moderated the effect of islets in affecting podocyte restoration and renal injury. Renal damage and podocyte injury were alleviated after DAPT treatment. Furthermore, the balance between apoptosis and autophagy was diverse under different treatments. All the data in this study showed that highly activated Notch-1 signaling could affect the therapeutic efficacy of islet transplantation on renal injury and podocyte restoration in high-glucose conditions. The balance between apoptosis and autophagy was also closely associated with the degree of podocyte restoration. This finding may suggest that the in vivo microenvironment plays a critical role in podocyte restoration after islet transplantation, which provides a promising and individual assessment and targeting treatment for different diabetic nephropathy patients after islet transplantation into the future.

Islet transplantation improved penile tissue fibrosis in a rat model of type 1 diabetes.

BACKGROUND: Glycaemic control is one of the most effective strategies for the treatment of diabetes-related erectile dysfunction (DMED). Compared to conventional anti-diabetic drugs and insulin, islet transplantation is more effective in the treatment of diabetic complications. The aim of this study was to investigate the efficacy of islet transplantation for reversing advanced-stage DMED in rats and to observe its influence on corpus cavernosum fibrosis. METHODS: Wistar rats were intraperitoneally injected with streptozotocin to establish a diabetes model. After 12 weeks, the rats were divided into 4 groups: diabetic, insulin, islet transplantation, and normal control. Following supplementation, the changes in blood glucose and weight were determined sequentially. Penile erectile function was evaluated by apomorphine experiments in the fourth week, and the penile corpus cavernosum was also collected for assessment by Masson staining, immunohistochemistry and Western blot to observe the spongy tissue and the related cellular changes at the molecular level. RESULTS: Islet transplantation significantly ameliorated penile erectile function in advanced-stage diabetic rats. The ratio of corpus cavernosum smooth muscle cells to fibroblasts and the expression level of α-SMA in the islet transplantation group were significantly higher than those in the diabetic and insulin groups. In addition, the expression levels of TGF-ß1, p-Samd2, and connective tissue growth factor (CTGF) in the islet transplantation and insulin groups were much lower than those in the diabetic group, while those in the islet transplantation group were significantly lower than those in the insulin group. CONCLUSIONS: Our findings strongly suggest that islet transplantation can promote the regeneration of smooth muscle cells and ameliorate corpus cavernosum fibrosis to restore its normal structure in advanced-stage diabetic rats. The possible mechanism of ameliorating corpus cavernosum fibrosis by islet transplantation may be associated with improvement of the hyperglycaemic status in diabetic rats, thereby inhibiting the TGF-ß1/Samd2/CTGF pathway.

Reversal of Early Diabetic Nephropathy by Islet Transplantation under the Kidney Capsule in a Rat Model.

Objective. Diabetic nephropathy (DN) is a common microvascular complication of diabetes mellitus, and insulin therapy has many side effects in the treatment of DN. Islet transplantation has emerged as a promising therapy for diabetic patients. This study was established to investigate its advantageous effects in a rat model of early DN. Methods. Streptozotocin was administered to the rats to induce diabetes. Twelve weeks later, the diabetic rats were divided into 3 groups: the islet-transplanted group (IT group), the insulin-treated group (IN group), and the untreated group (DN group). Renal injury and kidney structure were assessed by urinalysis and transmission electron microscopy (TEM) detection. Immunohistochemical staining and western blotting were performed to assess renal fibrosis levels. Results. The early DN features were reversed and the glomerular filtration barrier and basement membrane structures were improved at 4 weeks after islet transplantation. The urine microalbumin-to-creatinine ratio (ACR), protein-to-creatinine ratio, and mean thickness of the glomerular basement membrane (GBM) were significantly decreased in the IT group. The expression of renal fibrotic factors was also significantly decreased. Conclusions. These data suggest that early DN can be reversed after islet transplantation, and they may facilitate the development of a clinical therapeutic strategy for human diabetes mellitus.

Combined Microencapsulated Islet Transplantation and Revascularization of Aortorenal Bypass in a Diabetic Nephropathy Rat Model.

OBJECTIVE: Revascularization of aortorenal bypass is a preferred technique for renal artery stenosis (RAS) in diabetic nephropathy (DN) patients. Restenosis of graft vessels also should be considered in patients lacking good control of blood glucose. In this study, we explored a combined strategy to prevent the recurrence of RAS in the DN rat model. METHODS: A model of DN was established by intraperitoneal injection of streptozotocin. Rats were divided into 4 groups: SR group, MIT group, Com group, and the untreated group. The levels of blood glucose and urine protein were measured, and changes in renal pathology were observed. The expression of monocyte chemoattractant protein-1 (MCP-1) in graft vessels was assessed by immunohistochemical staining. Histopathological staining was performed to assess the pathological changes of glomeruli and tubules. RESULTS: The levels of urine protein and the expression of MCP-1 in graft vessels were decreased after islet transplantation. The injury of glomerular basement membrane and podocytes was significantly ameliorated. CONCLUSIONS: The combined strategy of revascularization and microencapsulated islet transplantation had multiple protective effects on diabetic nephropathy, including preventing atherosclerosis in the graft vessels and alleviating injury to the glomerular filtration barrier. This combined strategy may be helpful for DN patients with RAS.

Preparation and microscopy examination of alginate-poly-L-lysine-alginate microcapsules.

Ca-alginate-poly-l-lysine-alginate (APA-Ca) and Ba-alginate-poly-l-lysine-alginate (APA-Ba) microcapsules were prepared and their thickness and surface were examined by light microscopy and scanning electron microscopy. Specifically, light microscopy with frozen section was used to visualize and quantify the thickness of APA membrane, and monitor temporal changes in the thickness of microcapsules during a month long culture in vitro. The section graph of APA microcapsule represents the accurate measurement of layer thickness of APA-Ca with diameter 900 ± 100 and 500 ± 100 µm at 6.01 ± 1.02 and 9.54 ± 2.42 µm (p < 0.05), and layer thickness of APA-Ba with diameter 900 ± 100 and 500 ± 100 µm at 5.47 ± 0.90 and 8.21 ± 1.97 µm (p < 0.05), regardless of the alginate composition used to generate the microcapsules. The microcapsule was stable during the culture for 30 days in vitro. Field emission scanning electron microscopy with freeze drying method was used to detect the surface and thickness of dried microcapsules. From the results, the outer surface of APA-Ca and APA-Ba membrane were smooth and dense, the film thickness of the APA-Ca was about 450-690 nm, while the APA-Ba was approximately 335 nm. In vivo experiment, little significant difference was seen in the change of film thickness of microcapsules in intrapertioneal site for 30 days after transplantation (p > 0.05), except that the recovery of APA-Ba was higher than the APA-Ca microcapsules. The paper showed an easy method to prepare APA-Ca and APA-Ba, and examine their thickness and surface, which could be utilized to study other types of microcapsules.

Preparation and antitumor activity of bFGF-mediated active targeting doxorubicin microbubbles.

Characterization and antitumor activity of basic fibroblast growth factor-mediated active targeting doxorubicin microbubbles (bFGF-DOX-MB) were investigated. Pluronic F68 with chemical conjugation of doxorubicin (DOX-P) and peptide KRTGQYKLC-conjugated DSPE-PEG2000 were prepared. bFGF-DOX-MB had a normal distribution of particle size, with average particle size of 2.7 µm. Using A549 mouse model, bFGF-DOX-MB combined ultrasound showed the best inhibition effect on tumor volume growth among all the test groups. Similar conclusion was obtained from experimental measurements of tumor weight change and blood cell count. From the results, chemotherapeutic drug inhibition on tumor growth could be enhanced by local ultrasound combined with active targeting bFGF-DOX-MB, which might provide a potential application for ultrasound-mediated chemotherapy.

[Preparation and in vivo-in vitro evaluation of compound nanoparticles loaded with epirubicin hydrochloride and gadopentetate meglumine].

OBJECTIVE: To prepare and characterize the compound Epirubicin hydrochloride and Gadopentetate meglumine (Gd-DTPA) nanoparticles, and evaluate its properties from rabbits in vivo and in vitro. METHODS: The compound Epirubicin hydrochloride and Gd-DTPA nanoparticles were prepared by double emulsion-solvent evaporation method. The main effective factors were orthogonal designed. The characteristics such as drug entrapment efficiency, drug loading, and drug utilization were assayed in vitro. MR imaging effect of the VX2 rabbit hepatoma model were observed after injecting the drug-loaded nanoparticles through the hepatic artery intubation in vivo. RESULTS: The drug encapsulation efficiency of the nanoparticles, drug loading and drug utilization were 33.8% ± 3.4%, 0.225% ± 0.052%, and 69.6% ± 4.3% under the optimized prescription, respectively. The mean size of the nanoparticles was 180.6 nm, the drug release continued in 48 h with good MR imaging effect. CONCLUSIONS: Compound Epirubicin hydrochloride and Gd-DTPA Nanoparticles were in simply preparation and showed sustained drug release properties. These novel nanoparticles with detecting function could develop of epirubicin hydrochloride targeted therapy of liver cancer.

Experiment on formulation and drug release behavior of porosity asymmetric membrane capsules in vitro.

Porosity asymmetric membrane capsules were prepared to study the relationship between the capsule formulation and drug release. Cellulose acetate (CA) and pore formers were used in the capsule shell formulation as the main semipermeable membrane material. The capsules were permeable to both water and dissolved solutes. Using sparingly soluble drug acetaminophen as a model, cumulative release was calculated. The slope of the release profile from the distilled water had good relationship with the concentration of the pore formers F68. The release of acetaminophen was independent to the pH, osmotic pressure of dissolution medium, but influenced by intensity of agitation. When the concentration of pore former was low, zero-order release behavior was observed within 24 h which was consistent with Fickian diffusion model. When the concentration of pore former was high, however, Higuchi model release was found which is caused by Fickian diffusion and osmotic pressure release. With scanning electron microscope (SEM), the surface structure and cross-section of the capsule shell were also studied before and after drug delivery. With simple preparation and broad scope of drug application, porosity asymmetric membrane capsules can give desired drug extended release and show more convenience than controlled tablets with laser drilling.

Experiment on the feasibility of using modified gelatin nanoparticles as insulin pulmonary administration system for diabetes therapy.

Polymeric nanoparticles are widely used as targeted carriers for biomacromolecules. In this paper, modified gelatin nanoparticles were prepared and their feasibility as insulin pulmonary administration system was investigated. D: ,L: -glyceraldehyde and poloxamer 188 were used for gelatin nanoparticle preparation. Novel water-in-water emulsion technique was used to prepare insulin-loaded nanoparticles. Morphological examination of insulin-loaded nanoparticles was carried out using scanning electron microscopy (SEM). Intratracheal instillation of insulin-loaded nanoparticles was performed to evaluate animal hypoglycemic effect. With fluorescence labeling of insulin, alveolar deposition and absorption of insulin-loaded nanoparticles were investigated. Histological changes in the lung were also observed to evaluate the safety. From the micromorphology observation, insulin-loaded nanoparticles under gelatin-poloxamer 188 ratio at 1:1 showed smooth and uniform surface, with average particle size 250 nm and Zeta potential -21.1 mV. From animal experiment, insulin-loaded nanoparticles under gelatin-poloxamer 188 ratio at 1:1 promoted insulin pulmonary absorption effectively and showed good relative pharmacological bioavailability. Proved by alveolar deposition result, FITC-insulin-loaded nanoparticle group was characterized by an acute and rapid hypoglycemic effect. In addition, nanoparticles could guarantee the safety of lung by reducing insulin deposition in lung. A transient weak inflammatory response was observed at 1 day after administration. With good physical characterization, high bioavailability, fast and stable hypoglycemic effect, insulin-loaded nanoparticles might be developed as a novel insulin pulmonary system for diabetes therapy.

Comparing the enhancement efficiency between liposomes and microbubbles for insulin pulmonary absorption.

BACKGROUND: The present study investigated the enhancement efficiency between liposomes and microbubbles for insulin pulmonary absorption. METHODS: Two types of phospholipid-based vesicle-liposomes and microbubbles-were prepared, and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) cytotoxicity test was used to evaluate their in vitro toxicity in A549 cells. Cellular uptake of insulin combined with liposomes or microbubbles was determined using A549 cells. With intratracheal insufflation of Sprague-Dawley rats, an insulin mixture with liposomes or microbubbles was administered to assess its potential for promoting drug pulmonary absorption. RESULTS: Both liposomes and microbubbles had a narrow and monodispersed size distribution with average diameter of 3.1 µm and 1.0 µm, respectively. From the MTT cytotoxicity test, a phospholipid-based vesicle concentration of <25% (vol/vol) in the final volume was the safe dosage range that could avoid severe cytotoxic effects. The intracellular uptake amount of insulin in the insulin-microbubble mixture was significantly higher than that in the insulin-liposome mixture. The minimum reductions of the blood glucose concentration produced by insulin-microbubble and insulin-liposome mixtures were 60.8% and 35.0% of the initial glucose levels, respectively, and their bioavailabilities relative to subcutaneous injection were 48.6% and 30.8%, respectively. CONCLUSIONS: Microbubbles have much better efficiency than liposomes in the rate and extent of insulin pulmonary absorption. Microbubbles might be recommended as a potential agent for enhancing protein intrapulmonary absorption.

[Preparation and quality control of compound epirubicin hydrochloride-loaded polymeric nanoparticles of L-lactic-co-glycolic acid].

OBJECTIVE: To prepare compound epirubicin hydrochloride-loaded polymeric nanoparticles of L-lactic-co-glycolic acid and establish their quality control. METHODS: The emulsion-solvent evaporation method was employed to prepare and freeze-dry the compound epirubicin hydrochloride-loaded polymeric nanoparticles of L-lactic-co-glycolic acid after the addition of lactose. The contents and cumulative release of epirubicin hydrochloride and dimeglumine gadopentetate were detected simultaneously by RP-HPLC (reverse phase-high performance liquid chromatography). RESULTS: The above nanoparticles were prepared and the quality standards for simultaneously determining the contents of epirubicin hydrochloride and dimeglumine gadopentetate established primarily. The contents of epirubicin hydrochloride and dimeglumine gadopentetate in compound preparation were 100.6% ± 1.6% and 99.1% ± 1.9% respectively. And two compositions could be completely released within 9 days. CONCLUSION: The preparation method of nanoparticles is simple and their quality control feasible.

[Improved methods of isolation and purification of rat islets and its viability research].

OBJECTIVE: The purity and activity of islets will greatly affect the outcome of xenotransplantation therapy of type 1 diabetes mellitus. To set up an improved method of the isolation and purification of rat islets, which can obtain high-purity, high-yield, and high-viability islets. METHODS: Ten healthy and adult male SD rats, weighing 250-300 g were used as organ donors. Collagenase V was perfused into pancreas via pancreatic duct. Pancreas was digested with collagenase in water bath at 38 degrees C about 15 minutes, islet purification was performed using two techniques: with Ficoll 400 density gradient (group A), and Ficoll-Paque PLUS (group B). Dithizone (DTZ) was utilized for identifying islets, counting islets equivalent quantity (IEQ) and islets' purity. Trypan blue staining was used to detect the viability of islets. Islets of group B was encapsulated with alginate/poly-L-lysine/alginate (APA). Islets function of microencapsulated and nonmicroencapsulated was evaluated by the insulin release test. RESULTS: DTZ staining showed that islets shape were round, ellipse and irregular with a clear edge and a diameter range of 50-300 microm. The IEQ values were 338.04 +/- 76.61 and 834.80 +/- 54.00 in groups A and B, respectively, showing significant difference (P < 0.05). The purities were 88.31% +/- 2.67% and 95.63% +/- 1.96% in groups A and B, respectively, showing no significant difference (P > 0.05). The activities of islets were 67.40% +/- 5.15% and 86.05% +/- 2.52% in groups A and B, showing significant difference (P < 0.05). Islet APA microcapsules had round shape, unified size, and its diameter was between 1.5 and 2.0 mm. Each microcapsule was encapsulated of 1 to 3 islets. The result of insulin release assay was that the concentrations of insulin secretion with islets of microencapsulated and nonmicroencapsulated were (5.53 +/- 1.64) ng/mL and (4.76 +/- 0.26) ng/mL in low glucose, and its concentrations of insulin secretion in high glucose were (11.95 +/- 2.07) ng/mL and (14.34 +/- 3.18) ng/mL. Stimulated insulin secretion in high glucose was 2 times more than that in low glucose (P < 0.05), but there was no significant difference (P > 0.05) in the stimulation index between group A (2.16 +/- 0.30) and group B (3.01 +/- 0.59). CONCLUSION: The method of islets isolation and purification using Ficoll-Paque PLUS own the virtues of more convenient, high islet yield, and high islet purity. Both microencapsulated and nonmicroencapsulated islets show high-viability while culture in vitro.