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Angiogenesis refers to blood vessel formation through endothelial cell migration and proliferation. Angiogenesis is crucial and beneficial for wound healing and tissue regeneration. In the current study, we prepared porous collagen and collagen/hyaluronan (Col/HA) scaffolds composed of collagen (7 mg/mL) and hyaluronan (HA) (0.5 w%, 1 w%, and 1.5 w%) as culture vehicles for coculture of human adipose-derived stem cells (hADSCs) and human umbilical vein endothelial cells (HUVECs). These scaffolds were combined with low-intensity pulsed ultrasound (LIPUS) to investigate and evaluate angiogenesis in the coculture cell/scaffold constructs in vitro and in vivo. Scaffold porosity decreased (from 74.4% to 60.7%) and readily degraded after addition of various ratios of HA. The porous scaffolds all had high water content (~98%) and similar mechanical properties. The hADSCs alone and hADSCs cocultured with HUVECs exhibited stable proliferative profiles on the Col/HA scaffolds; furthermore, LIPUS significantly enhanced cell growth on the collagen and Col/0.5HA scaffolds by approximately 1.85- and 1.5-fold, respectively, compared with the cells that did not receive LIPUS treatment. In vivo immunohistochemistry results indicated stronger immunofluorescent CD31 presence and vascular endothelial cadherin messenger RNA expression in the hADSCs/HUVECs coculture/scaffold implantation in rats that received LIPUS treatment compared with those that received no such treatment. Our results demonstrated that the hADSCs/HUVECs cocultured on fabricated collagen and Col/HA scaffolds combined with LIPUS treatment had angiogenesis-promoting capability and therapeutic potential when angiogenesis is demanded.

Polydimethylsiloxane (PDMS) is often used in flexible electronic skin, due to their non toxic and tough. However, the lack of degradation and cell biocompatibility of PDMS would limit the potential use in the biological field. To overcome the limitation, PDMS was modified by surface treatment for enhancing cell adhesion and proliferation. This research is focused on preparation and evaluation of novel chitosan biocompatible electronic skin. Chitosan electronic skin was prepared by a thermal induced phase separation method, following treatment with NaOH gelating agent, followed by analyzing the surface morphology, swelling behavior, mechanical strength, degradation rate. The electrode was produced by screen printing technique, followed by analyzing the adhesion between the ink and cell biocompatibility. From scanning electron microscope (SEM) observations, NaOH gelated chitosan skin had the smooth surface morphology. The swelling ratio of all chitosan skin gelated by NaOH were less than 5%. The chitosan skin, prepared by 300k kDa chitosan gelated by NaOH for 3hr, had the smallest swelling ratio. Furthermore, its mechanical strength showed the highest value of Young’s modulus (∼151 kPa). It indicated that 300 kD chitosan skin gelated by NaOH for 3hr had better size stability. All chitosan skins degraded about 20% of initial weight after 40 days in vitro shaking test. The adhesion strength of the silver inks on the surface of chitosan was better than carbon ink, and the electrical characteristic is almost the same with commercial polycarbonate (PC) substrate. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay and SEM observation indicated that chitosan skin with silver electrode showed the cell biocompatibility. By further increasing the application of both screen imprinting technique and biopolymer, the idea of interdisciplinary can be achieved and it would be a creative revolution to the field of wearable device into tissue engineering.

Hydrothermal carbon (HTC) is typically well-dispersed, but it remains a great challenge for HTC to become conductive. Co-doping with heteroatoms has been confirmed to be an effective strategy to significantly promote the electrical conductivity of carbon. Moreover, there is no simple and green method to construct sensitive HTC based electrochemical biosensors until now. In this paper, N and S dual-doped carbon (NS-C) with ultra-low charge transfer resistance is easily synthesized from L-cysteine and glucose in a hydrothermal reaction system. The morphology, structural properties and electrochemical properties of the as-prepared NS-C are analyzed. In comparison with the undoped hydrothermal (UC) modified glassy carbon electrode (GCE), the charge transfer resistance of UC (476 Ω) is ten times the value of NS-C (46 Ω) . The developed biosensor shows a better performance to detect glucose in a wide concentration range (50–2500 μmol L−1) with the detection limit of 1.77 μmol L−1 (S/N=3) and a high sensitivity (0.0554 μA cm−2 μmol−1 L). The apparent Michaelis-Menten constant value of GCE/NS-C/GOx/nafion modified electrode is 0.769 mmol L−1, indicating a high affinity of glucose oxidase to glucose. These results demonstrate that the hydrothermal method is an effective way for preparing high electrical conductivity carbon with excellent performances in biosensor application.

Advances and improvements in mesenchymal stromal/stem cells (MSCs) and cell replacement therapies have been promising approaches to treat diabetes mellitus (DM) since their potent capacities for differentiation into various functional cells match the demands of tissue repair and regeneration. The aim of this study is to examine the effects of nano-sized type I collagen molecules in combination with nicotinamide (NCT) and exendin-4 (EX4) on MSC differentiation into insulin-secreting cells in vitro and to evaluate their reparative effects against type 2 diabetes mellitus (T2DM) in vivo. Differentiation of MSCs in the presence of NCT, nano-sized type I collagen molecules and EX4 was represented with insulin production and Nkx6.1/PDX-1 mRNA expression assessed by insulin secretion assay and quantitative RT-PCR. Histopathological and glycosylated haemoglobin (HbA1) analysis was performed to assess reparative effects against T2DM in the rat model. The results revealed that MSCs showed increased differentiation into insulin-secreting cells with higher mRNA expression for Nkx6.1 and early PDX-1 in the presence of NCT and nano-sized type I collagen molecules. Addition of nano-sized type I collagen fibrils increased morphologically islet-like clusters in differentiated cells. T2DM rats reverted to their normal HbA1 values and exhibited structurally repaired islets in the pancreas implanted with NCT/nano-sized collagen I molecule/EX4-incubated differentiated cells. In short, the combined recipe showed reparative actions on the destructive islet of Langerhans in the pancreas coupled with glucoregulatory effects in T2DM rats in vivo. Therefore, MSCs incubated with NCT/EX4 and nano-sized collagen I molecules could be a potential therapy for retrieval of destructed islets and could efficiently regulate blood glucose in T2DM.

Volvox sphere is a biomimetic concept of a natural Volvox, wherein a large outer sphere contains smaller inner spheres, which can encapsulate cells and provide a double-layer three-dimensional environment for culturing cells. This study simultaneously encapsulated rat mesenchymal stem cells (MSCs) and AML12 hepatocytes in volvox spheres and extensively evaluated the effects of various culturing modes on cell functions and fates. The results showed that compared with a static flask culture, MSCs encapsulated in volvox spheres differentiated into hepatocyte-like cells with a 2-fold increase in albumin (ALB) expression and a 2.5-fold increase in cytokeratin 18 expression in a dynamic bioreactor. Moreover, the restorative effects of volvox spheres encapsulating cells on retrorsine-exposed CCl4-induced liver injuries in rats were evaluated. The data presented significant reductions in AST and ALT levels after the implantation of volvox spheres encapsulating both MSCs and AML12 hepatocytes in vivo. In contrast to the negative control group, histopathological analysis demonstrated liver repair and formation of the new liver tissue in groups implanted with volvox spheres containing cells. These results demonstrate that liver cells implanted with volvox spheres encapsulating both MSCs and AML12 hepatocytes promote liver repair and liver tissue regeneration in liver failure caused by necrotizing agents such as retrorsine and CCl4. Hence, volvox spheres encapsulating MSCs and liver cells can be a promising and clinically effective therapy for liver injury. Statement of Significance In this study, we used a volvox sphere, which is a unique design that mimics the natural Volvox, that consists of a large outer sphere that contains smaller inner spheres, which provide a three-dimensional environment to culture cells. The purpose of this study is to co-culture mesenchymal stem cells (MSCs) and AML12 liver cells in volvox spheres and evaluate two different culture methods, dynamic bioreactor and static culture flask,on the cultured cells. In addition, we aimed to evaluate the restorative effects of volvox spheres encapsulating MSCs and/or AML12 liver cells on rats with retrorsine-exposed CCl4-induced liver injuries. The results showed that MSCs encapsulated in volvox spheres differentiated into hepatocyte-like cells with a 2-fold increase in albumin expression and a 2.5-fold increase in cytokeratin 18 expression ina dynamic bioreactor. Moreover, the data presented significant reductions in AST and ALT levels after the implantation of volvox spheres encapsulating both MSCs and AML12 hepatocytes in vivo. In contrast to the negative control group, histopathological analysis demonstrated liver repair and formation of new liver tissue in groups implanted with volvox spheres containing cells. These results demonstrate that liver cells implanted with volvox spheres encapsulating both MSCs and AML12 hepatocytes promote liver repair and liver tissue regeneration in liver failure caused by necrotizing agents such as retrorsine and CCl4. Hence, volvox spheres encapsulating MSCs and liver cells can be a promising and clinically effective therapy for liver injury.

Currently, transgenic chickens are a popular method for pharmaceutical protein production. In this study, we employed cationized gelatin/calcium phosphate nanoparticles (ca-GCaPs) with surface modification by cholaminchloride hydrochloride as gene carriers to produce transgenic chickens. To evaluate the transfection efficiency, a plasmid (pEGFP-C1) was encapsulated in the ca-GCaPs for HeLa cells transfection. The ca-GCaPs were applied as gene carriers by direct injection into the area opaca of the chicken embryo blastodisc to produce the transgenic chicken. The particle size of the ca-GCaPs was 350 nm and the zeta potential was +15 mV. Plasmids encapsulated in the ca-GCaPs prevented from DNase I degradation. Based on biocompatibility analysis, the ca-GCaPs produce higher cell viability and less cytotoxicity compared to the commercially available product Lipofectamine™ 2000. The in vitro study indicated that the transfection rate using ca-GCaPs was higher than using cationized gelatin nanoparticles (ca-GPs) because calcium phosphate can provide osmotic pressure to break down lysosomes. In the in vivo study, the egg hatch rate was 100% after ca-GCaPs transfection, and green fluorescence protein expression could be observed in chicken tissue on the fourth day after transfection.

Effective cancer therapy relies on delivering the therapeutic agent precisely to the target site to improve the treatment outcome and to minimize side effects. Although surgery, chemotherapy, and radiotherapy are the standard methods commonly used in clinics, hyperthermia has been developed as a new and promising strategy for cancer therapy. In this study, magnetic bioceramic hydroxyapatite (mHAP) nanocrystals have been developed as heat mediator for intracellular hyperthermia. Hyaluronic acid (HA) modified mHAP nanocrystals are synthesized by a wet chemical precipitation process to achieve active targeting. The results demonstrate that the HA targeting moiety conjugated by a poly(ethylene glycol) (PEG) spacer arm is successfully immobilized on the surface of mHAP. The HA-modified mHAP possesses relatively good biocompatibility, an adequate biodegradation rate and superparamagnetic properties. The HA-modified mHAP could be localized and internalized into HA receptor-overexpressed malignant cells (e.g., MDA-MB-231 cell) and used as the heat generating agent for intracellular hyperthermia. The results from this study indicate that biocompatible HA-modified mHAP shows promise as a novel heat mediator and a specific targeting nanoagent for intracellular hyperthermia cancer therapy.

The aim of this study was to prepare and evaluate chitosan dressings treated with sodium hydroxide (NaOH) and/or sodium tripolyphosphate (Na 5 P 3 O 10 ) for haemostatic use. The pure sodium hydroxide-gelled chitosan dressing (CS-B) had water contents (about 95%) and porosities (about 85%) which were similar to those of commercially available chitosan-based products. The CS-B dressing also exhibited homogeneously sized and penetrating pores throughout, whereas the commercially available Clo-Sur PAD showed porous lamellar structures inside and Instant Clot Pad exhibited a heterogeneous pore size distribution. Additionally, the CS-B dressing was flexible and resilient, free of odour and able to recover completely after compression in a hydrated state. Finally, the CS-B sponge absorbed blood quickly, accelerating blood clotting, enhancing red blood cell adhesion and maintaining its original shape after haemostatic testing.

Objectives: The aim of this article is to introduce a new technique, named the “double balloon occlusion technique” (DBOT), for the salvage of acutely thrombosed grafts and to demonstrate its safety and efficacy. Background: Acute thrombosis is recognized as the most common factor of acute graft failures. A suitably percutaneous technique should be devised to remove thrombi safely and effectively. Care should also be taken to prevent possible thromboembolic complications during procedures. Mainly composed of two balloons, the percutaneous DBOT has been developed to meet the clinical needs. Methods: Thirty-two patients with graft failures undergoing the DBOT were recruited between May 2007 and May 2008. The DBOT is itemized in the text and a practical case undergoing successful DBOT is also demonstrated. Results: Of the 32 DBOT treatments, the procedural success rate was 100% (32/32). The clinical success rate was 94% (30/32). One complicated case with severe hematoma resulting from a balloon-induced graft rupture received surgery, although the graft outflow restored. The mean procedure time was 92 minutes. Three patients died and two patients were lost within the 3-month follow-up. The 3-month graft patency rate was 70% (19/27). Conclusion: The DBOT has the potential to be operated safely and effectively. Preliminary results had high success rates and patency rates. With basic devices, it may serve as an option to rescue thrombosed grafts. More data are needed to identify its clinical role. © 2008 Wiley-Liss, Inc.

Boron nitride (BN) is one of III–V compounds widely applied on the electrical industry. It has been fabricated by numerous techniques, but so far there is no reliable method to produce pure and high-yielding BN nanotubes at relatively lower temperature. Therefore, the exploration on its synthesis is still a challenging subject. In the study, the BN nanotube would be synthesized by thermal-heating chemical vapor deposition (TH-CVD) with trimethyl borate evaporated at 60 °C and nitrogen gas flew into reaction chamber as the source of B and N, respectively. 434 stainless steel wires will be coiled as an entangled wire scaffold with pore size of 1 mm and then placed in the middle part of reaction chamber. The metallic ions contained in the stainless steel will serve as the catalysts for of BN nanotube in situ growth. From the results of SEM, HRTEM, FTIR and XRD analysis, hexagonal-BN (h-BN) and orthorhombic-BN (o-BN) nanotubes were successfully synthesized at relatively low temperature between 1000 and 1200 °C. All the nanotubes prepared in the system were identified as h-BN and o-BN. At reaction temperature of 1200 °C, several types of BN morphology appeared. The BN nanotubes could be obtained at the temperature between 1000 and 1100 °C. However, BN nanotubes for the latter temperature grow into larger size tube. The optimum reaction temperature for BN nanotube synthesis is 1000 °C. The reproduction property of synthesized BN nanotube by this method is very promising. The method should have a great potential to prepare BN nanotube in the future.

In the study, we are going to develop a tri-layer membrane as the artificial skin for extensive burn injury. The first layer is a three-dimensional tri-copolymer sponge of gelatin/hyaluronan/chodroitin-6-sulfate with 70% in porosity and 20–100 μm in pore size. The layer is constructed as a dermis analogous layer to stimulate capillaries penetration, to promote dermal fibroblast migration and to induce the secretion of extra-cellular matrix, which provides a better physiological environment for burn patient recovery. The second layer is as so called auto-stripped layer composed by poly-N-isopropyacrylamide (PNIPAAm). The layer will be automatically peeled off from the tri-copolymer layer once the wound site closed and recovered. The third layer is composed by polypropylene (PP) non-woven fabric, which provides an open structure for exudates drainage out that will reduce the risk of second infection. The tri-layer wound dressing has been successfully prepared by subsequently high-energy plasma treatment, γ-ray irradiation, UV light exposure, and lyophilized process. From the results of MTT, IL-8, IL-1α, IL-6, and TNF-α measurement, the developed material will not induce tissue inflammatory or immune response. The dermal fibroblasts showed initial contact with the material surface through the radial extension of filopodia followed by cytoplasmic webbing that could be examined by SEM. Dermal fibroblasts subsequently flattened for further proliferation and extra-cellular matrix secretion. Dermal analog layer provides a three-dimensional architecture for normal dermis regeneration. The layer can be completely biodegraded within 4 weeks post-operation. After served as a scaffold for the ingrowth of self-fibroblasts, a normal dermis like layer will be regenerated. The dressing will fall off automatically without any damage once the wound site healed completely.

Objectives: The aim of this study was to investigate the changes of regional tissue Doppler velocity after volume removal following regular hemodialysis (HD) in uremic patients. Is tissue Doppler velocity really preload-independent? Background: Diastolic dysfunction was divided into four stages: normal pattern, abnormal relaxation pattern, pseudonormalization pattern, and restrictive pattern. Pulse wave Doppler and color Doppler echocardiography were important diagnostic tools for these forms of diastolic dysfunction. However, they were preload-dependent and sometimes there was confusion between the normal pattern and the pseudonormalization pattern. Tissue Doppler echocardiography was promising for problems in diastolic dysfunction and appeared to be preload-independent. However, there are still some disputes over this point. Methods: Ninety-three uremic patients receiving regular HD were included in the study. There were 45 males and 48 females aged 59 ± 14 years. The mean volume removed after HD was 2.3 ± 0.9 kg. The mean heart rates before and after HD were 77 ± 11 and 76 ± 12 beats per minute, respectively (p = 0.73). All patients received complete transthoracic echocardiography examinations before and after HD. The studies included cardiac chamber size, left ventricular systolic performance, pulse wave Doppler echocardiographic data of mitral inflow and the right upper pulmonary vein including peak velocity of early diastolic E wave, E wave time velocity integral (TVI-E), peak velocity of late diastolic A wave, A wave TVI, systolic phase of pulmonary vein (S wave TVI), early diastolic phase of pulmonary vein (D wave TVI) and atrial contraction phase of pulmonary vein (Ar wave TVI). Pulsed tissue Doppler echocardiography (TDE) was performed and a 4-mm sample volume was placed at the 6 corners of the mitral annulus including septal, lateral, anterior, inferior, anteroseptal and posterior corners. Five to ten cardiac cycles were recorded and the data were averaged. Measurements performed included peak velocity of systolic phase (Sa), early diastolic phase (Ea), late diastolic phase (Aa), Ea/Aa ratio and time from the beginning of electrocardiogram Q wave to the beginning of Sa (Q-Sa time). The same measurements were repeated after HD. Results: After HD, left atrium diameter and left ventricular internal dimensions at end diastole became smaller. There were significant reductions for mitral peak E wave velocity, TVI-E, peak A wave velocity and E/A ratio. As for the pulmonary vein, systolic phase of pulmonary vein and early diastolic phase of pulmonary vein decreased significantly. Peak Ar wave did not change significantly. For TDE, Sa and Aa did not change but Ea did decrease. Conclusion: After HD, there is a significant reduction of intravascular effective volume. No significant change is found for myocardial peak systolic velocity and peak late diastolic velocity. However, there is a significant reduction of myocardial early diastolic phase peak velocity. This suggests that TDE is not completely preload-independent; at least, it is phase-dependent within each cardiac cycle.

Introduction: Pulmonary arterial hypertension (PAH) is a progressive disorder characterized by the increased vascular resistance and the remodeling of pulmonary arteries. Evidences of accumulated inflammatory cells in the lung suggested that chronic inflammation might play a role in PAH. Regenerative cell therapy emerged as a potential treatment for PAH through regulating the host’s immune response. Hypothesis: The secretome of induced pluripotent stem cells (iPSCs) was investigated for their preventive and therapeutic effects in the pathogenesis of monocrotaline (MCT)-induced PAH rat. Methods: PAH was developed by the subcutaneous injection of MCT in rats. The conditioned medium of cultured iPSCs (iPSC CM) was applied daily in prevention (an hour after MCT injection) or reversal (14 days after MCT injection) by IP injection throughout the full 28 days of experiment. The effects of iPSC CM were interpreted by the analyses of systolic pressure (RVSP) and the hypertrophy index of right ventricle, also the regulation of inflammation in lung and the underlying mechanism. Results: Both prevention and reversal, the hemodynamic values of RVSP and hypertrophy index were significantly improved in MCT-induced PAH rats after iPSC CM treatment. Attenuated expression of pro-inflammatory M1 macrophage markers was observed in either the lung of MCT-induced PAH rats or in co-cultured human M1 macrophages after iPSC CM treatment. To investigate the potential molecules secreted by iPSCs into iPSC CM, two major ingredients, named α1-antitrypsin and feutin-a, were identified by protein mass spectrometry and confirmed by western blotting with specific antibodies. Both components were mentioned to be involved in the anti-inflammatory effects observed in various lung diseases. Conclusions: In this study, iPSC CM represented therapeutic benefits on MCT-induced PAH rats though attenuating inflammation. Molecules exhibit anti-inflammatory potential existed in the iPSC CM, such as α1-antitrypsin and feutin-a, might hold the promise as new therapeutics of regenerative cell therapy via paracrine mechanism.

Thermal-heating chemical-vapor deposition has been used to synthesize Si3N4 nanotubes by heating tetra-ethyl-ortho-silicate at 165 °C to get vapor to flow in and providing nitrogen gas to the reaction chamber as the source of Si and N, respectively. A stainless-steel wire was coiled as entangled wire scaffold with a pore size of 1 mm. The wire scaffold was placed in the middle part of the reaction chamber. Cr, Fe and Mo, contained in the stainless-steel, served as catalysts to provide in situ growth of Si3N4 nanotubes on the coil surface at a relative low reactant temperature (1000 °C) through the vapor–liquid–solid growth mechanism. Most of the nanotubes are end-closed by a metallic particle. All the nanotubes were identified as α-Si3N4 in crystal structure.

The thermal and degradable properties of carbodiimide (EDC) or glutaraldehyde (GTA) cross-linked gelatin membranes have been investigated in order to evaluate the effects of different concentrations of two kinds of cross-linking reagent on the stability of membranes. In the thermogram recorded from a gelatin membrane cross-linked with EDC solution, the endothermic peak of 0.8% EDC cross-linking gelatin was centered at about 61°C that was higher than other samples treated with EDC solutions. Denaturation temperature (Td) of gelatin samples increased on increasing EDC concentration (0.2% to 0.8%), in agreement with the simultaneous increased of the extent of cross-linking. But increasing GTA concentration from 0.05% to 0.6%, the Td values of gelatin samples were decreased from 66.2°C to 56.3°C . In addition, two endothermic peaks were observed in 0.4% and 0.6% GTA cross-linking groups because of the GTA concentration was too high to complete cross-linking reaction. Therefore, partial of gelatin membrane was cross-linked completely but others were not. In the thermogravimetric analysis, the proportion of cracking endothermic peak of 0.6% GTA cross-linking gelatin (g15G0.6) was higher than the peak of 0.6% EDC cross-linking gelatin (g15C0.6). Therefore, g15G0.6 cracked to smaller molecules has to absorb more calorific capacity than g15C0.6. The increase in the strength of covalent binding on increasing the proportion of endothermic peak was evident. The results of degradable rate were in agreement with the lower concentration of cross-linked reagent the faster degraded rate of gelatin membrane. The MTT assay showed that 15% gelatin cross-linked by 0.8% EDC has the least cytotoxicity, and cell activity of this group was similar to control group (blank dish). As the concentration of GTA in gelatin membranes was down to 0.05% or 0.1% the cell viability was returned to approach the value of control group.

The aim of this study was to investigate the ability of nano-sized collagen I molecules (nanoparticles or nanofibrils) and a 5-azacytidine (5-aza) treatment to enhance the differentiation of rat mesenchymal stem cells (MSCs) toward a cardiomyogenic phenotype in vitro. Second passaged MSCs were cocultured with nano-sized collagen I molecules for 24 h and then treated with 10 μM 5-aza for 24 h. The results demonstrated that the size of the cells increased significantly and acquired a flattened, triangular-shaped morphology after treatment with nano-sized collagen I molecules and 5-aza. The cells are connecting with adjoining cells by forming myotube-like structures. Additional treatment of the MSCs with nano-sized collagen I fibrils significantly increased two transcription factors GATA-4 (12.6-fold increase) and Nkx2.5 (4.8-fold increase) expressions compared with MSC groups treated only with 5-aza at 3-day culturing. Furthermore, MSCs pretreated with nano-sized collagen fibrils significantly increased the expressions of cardiac genes of troponin I, β-myosin heavy chain, and cardiac α-actin compared with MSC groups treated only with 5-aza (all, p0.01 or better). These results indicate that culturing MSCs with nano-sized collagen I molecules, which may act as scaffolds or soluble protein ingredients, leads to alterations in gene expression and affects the differentiation fate induced with 5-aza.

Mitral regurgitation (MR) of even mild severity affects the prognosis of patients with acute coronary syndrome (ACS). The present study retrospectively analyzed 1,142 patients with ACS and MR of varying severity. Of the 95 patients with severe MR, 57 (60%) underwent primary percutaneous coronary intervention only and 38 (40%) underwent coronary artery bypass grafting (CABG) and mitral valve replacement (MVR). The severity of MR was significantly associated with the risk of heart failure but not with in-hospital or long-term mortality. In patients with severe MR, in-hospital mortality was no greater in those treated with CABG and MVR than in those treated with percutaneous coronary intervention alone. However, the incidence of long-term hard events (heart failure and all-cause mortality) was lower in those who had received the combined treatment. Multivariate analysis showed that, compared to percutaneous coronary intervention alone, CABG combined with MVR at the acute phase of ACS resulted in a significantly improved prognosis (odds ratio 0.172, 95% confidence interval 0.046 to 0.649, p = 0.009), even after adjusting for age, left ventricular filling pressure, and ejection fraction. In conclusion, the severity of MR in patients with ACS is associated with long-term heart failure events. Even at the acute phase of ACS, CABG combined with MVR results in an acceptable in-hospital mortality rate. The combined strategy also reduced the long-term hard events.

Atrial fibrillation (AF), a common complication after coronary artery bypass graft surgery (CABG), is associated with prolonged hospital stay. This prospective study assessed the accuracy of left atrial parameters and additional preoperative characteristics for predicting post-CABG AF and in-hospital mortality.A total of 197 patients without hemodynamic-significant valvular problems, who received isolated CABG, were enrolled. Echocardiography was performed before CABG.Compared with patients without post-CABG AF, those with post-CABG AF were older (71 vs 64 years, p0.0001), had a higher incidence of CABG during index hospitalization of acute myocardial infarction and preoperative respiratory failure requiring ventilator support, lower left ventricular ejection fraction (0.41 vs 0.48, p0.0001), lower left atrial expansion index (52.2% vs 93.3%, p0.0001), and higher left ventricular filling pressure (24.2 vs 19.1 mm Hg, p0.0001). Multivariate analysis of preoperative variables showed that independent predictors of AF included age (odds ratio [OR], 1.064; 95% confidence interval [CI], 1.022 to 1.107 per 1-year increase; p 0.002), maximal indexed left atrial volume (OR, 1.026; 95% CI, 1.002 to 1.051 per 1 mL/m2 increase; p 0.037) and left atrial expansion index (OR, 0.981; 95% CI, 0.962 to 0.998 per 1% increase; p 0.029). The left atrial expansion index was also significantly associated with in-hospital mortality (OR, 0.982; 95% CI, 0.951 to 0.996 per 1% increase; p 0.042). Incidence of post-CABG AF in patients with left atrial expansion index less than 120% progressively increased as left atrial expansion index decreased.Left atrial expansion index independently predicts post-CABG AF and in-hospital mortality.

Eighty-nine infants with clinical evidence of a large ventricular septal defect (VSD), refractory to conventional medical treatment, underwent surgical closure within the first 12 months of life from August 1987 to December 1991. There were 54 males and 35 females. The ages of the patients ranged from 2 to 12 months, with a mean age of 6.4 months. The mean body weight of the patients was 5.2 kg (range 2.3 to 10 kg). Surgery was performed because of intractable heart failure in 38 infants (43%), failure to thrive in 49 (55%), repeated pneumonia in 53 (60%) and prolonged endotracheal intubation in 10 (11%). There were 27 patients with a supracristal VSD (30%), and 62 patients with perimembranous VSD (70%). Eleven patients (12%) had pre-operative cardiac catheterization. Transatrial repair of perimembranous VSDs and transpulmonary repair of supracristal VSDs was used exclusively without ventriculotomy in our institution. Surgically induced heart block did not occur in any of the patients. Only 2 patients (2.2%) died during the early post-operative period. Diagnosis in most cases was confirmed by the present advanced integrated colour Doppler echocardiographic technology which is widely used by paediatric cardiologists. There is no need to perform cardiac catheterization in most patients with VSD. The morbidity and mortality were low. We strongly suggest that transatrial or transpulmonary primary repair without ventriculotomy can be successfully accomplished in almost all infants with a large VSD. Key words: ventricular septal defect, infant, surgery.

Platelet gels (PG), activated by bovine thrombin (BT), have increasingly been used in orthopedic surgery. However, BT may induce immunological reactions and carry potential viral and prion risks. To avoid these side effects, thrombin derived from human plasma (human thrombin, HT) is becoming the preferred platelet activator to prepare PG. However, limited experience and data on the clinical benefits of HT-generated PG (HTPG) in orthopedic surgery is reported. Consequently, we designed and performed a series of studies in dogs to compare the impacts of promotion of bone growth by an artificial bone substitute (Osteoset) in combination with HTPG or without it in the spinal repair experiments. X-ray observations and histological studies were performed at predetermined periods post-operation. The preliminary results revealed the preparation of HTPG was easy and required less than 30 minutes. HTPG was capable of embedding the artificial bone substitute Osteoset to prepare a sticky and easily manipulated composite for the application into spinal defect. We found HTPG exhibited enhancement of grafting capacity in consolidation of bone mass. After 12 weeks, tissue reconstruction reached approximately 80% of the injury defects when treated by HTPG/Osteoset combination, but only 30 approximately 40% in the absence of HTPG. The physiological activity of artificial bone substitute combined with PG activated by HT may therefore open beneficial prospects for more successful and safer bone formation in spine procedures in the near future.

Early reperfusion in the setting of an ST-elevation myocardial infarction is utmost importance. However, to provide optimal care to patients with ST-segment elevated myocardial infarction (STEMI) is challenging. If a patient suffers from chest pain and calls the emergency number, initiation of a

In this study, we have evaluated the feasibility of developing a biodegradable collagenous small diameter vascular graft of 2mm diameter and 1cm length. In brief, bi-layer type I collagen membrane was fabricated under vacuum suction and lyophilization methods. The smooth muscle cells were inoculated into the lower side of the porous membrane, while endothelial cells were seeded onto upper smooth side of the membrane. After cultured for 7 days, the vascular substitute was either harvested for in vitro examination or in vivo implanted in the subcutaneous layer for biocompatibility test. The tubular vascular prosthesis was then used as a temporary absorbable guide that served as an in vivo vascular graft to promote the complete regeneration of rat inferior vena cava. After implantation for 12 weeks, a thin continuous layer of endothelial cells and smooth muscle cells were lined with the vascular lumen and tunic media, respectively. Histology results showed that there were no signs of significant thrombogeneity and intima hyperplasia. This tissue engineered vascular substitute not only had enough tensile strength and good biocompatibility, but also advanced vascular regeneration. In the future, we suggest that this biodegradable vascular substitute will provide with the possibility in application on small diameter prosthetic grafts in artificial blood vessels.

Alternative strategies to optimize preexisting cardioplegia during myocardial preservation are currently under extensive investigation. Adenosine, an endogenous purine nucleoside, has been approved for its cardioprotective potential against ischemic-reperfusion injury. Yet, little information is available with respect to the use of adenosine for cardioplegic induction in humans. The purpose of the present study was, therefore, to assess the clinical relevance of intra-aortic administration of adenosine following aortic cross-clamping with respect to the exertion of additional protection in routine coronary artery bypass surgery.Thirty patients to receive elective coronary artery bypass grafting under cardiopulmonary bypass (CPB) were prospectively randomized into two study groups. Immediate after aortic cross-clamping and just before the application of modified St. Thomas cardioplegic (20 mL/kg), adenosine solution (250 microg/kg) was injected into the aortic root in the study group (n = 15), while the same amount of normal saline injection was administered in the control group (n = 15). Anesthesia was carried out in all patients in a similar fashion, and all the surgeries were performed by the same team. Homodynamic change, cardiac enzyme assay, and post-bypass inotropic supplementation were recorded throughout the study period to evaluate the extent of myocardial ischemic injury.The mean time to asystole after aortic cross-clamping was significantly shorter for the adenosine group compared with the control group (8.1 +/- 5.9 vs. 79.0 +/- 35.3 sec, respectively; P0.01). To compare with the baseline value, the mean cardiac index immediately post CPB and 24 hours postoperatively was increased significantly for the adenosine group (from 2.1 +/- 0.6 to 2.6 +/- 0.6 and 3.2 +/- 0.6 L/min/m2, respectively; P0.05), as contrasted with the control group (from 2.3 +/- 0.5 to 2.0 +/- 0.4 and 2.5 +/- 0.4 L/min/m2). Further, the requirement for inotropic support after CPB and postoperative troponin I release were significantly less in the adenosine group. There appeared no adverse effects associated with adenosine administration.Immediate administration of 250 microg/kg adenosine via the aortic root following aortic cross-clamping could optimize the myocardial protective effect of conventional cardioplegia, quicken cardiac standstill, and offer better postoperative myocardial performance after CPB.