A tissue-engineered, decellularized, connective tissue membrane for allogeneic arterial patch implantation.

BACKGROUND: We have previously applied in vivo tissue-engineered vascular grafts constructed in patients' subcutaneous spaces. However, since the formation of these vascular grafts depends on host health, their application is challenging in patients with suppressed regenerative ability. Therefore, the allogeneic implantation of grafts from healthy donors needs to be evaluated. This study aimed to fabricate allogeneic cardiovascular grafts in animals. MATERIALS AND METHODS: Silicone rod molds were implanted into subcutaneous pouches in dogs; the implants, along with surrounding connective tissues, were harvested after four weeks. Tubular connective tissues were decellularized and stored before they were cut open, trimmed to elliptical sheets, and implanted into the common carotid arteries of another dog as vascular patches (n = 6); these were resected and histologically evaluated at 1, 2, and 4 weeks after implantation. RESULTS: No aneurysmal changes were observed by echocardiography. Histologically, we observed neointima formation on the luminal graft surface and graft wall cell infiltration. At 2 and 4 weeks after implantation, α-SMA-positive cells were observed in the neointima and graft wall. At 4 weeks after implantation, the endothelial lining was observed at the grafts' luminal surfaces. CONCLUSION: Our data suggest that decellularized connective tissue membranes can be prepared and stored for later use as allogeneic cardiovascular grafts.

Evaluation of time courses of agreement between minutely obtained transcutaneous blood gas data and the gold standard arterial data from spontaneously breathing Asian adults, and various subgroup analyses.

BACKGROUND: Usual clinical practice for arterial blood gas analysis (BGA) in conscious patients involves a one-time arterial puncture to be performed after a resting period of 20-30 min. The aim of this study was to evaluate the use of transcutaneous BGA for estimating this gold standard arterial BGA. METHODS: Spontaneously breathing Asian adults (healthy volunteers and respiratory patients) were enrolled (n = 295). Transcutaneous PO2 (PtcO2) and PCO2 (PtcCO2) were monitored using a transcutaneous monitor (TCM4, Radiometer Medical AsP, Denmark) with sensors placed on the chest, forearm, earlobe or forehead. Transcutaneous BGA at 1-min intervals was compared with arterial BGA at 30 min. Reasonable steps to find severe hypercapnia with PaCO2 > 50 mmHg were evaluated. RESULTS: Sensors on the chest and forearm were equally preferred and used because of small biases (n = 272). The average PCO2 bias was close to 0 mmHg at 4 min, and was almost constant (4-5 mmHg) with PtcCO2 being higher than PaCO2 at ≥8 min. The limit of agreement for PCO2 narrowed over time: ± 13.6 mmHg at 4 min, ± 7.5 mmHg at 12-13 min, and ± 6.3 mmHg at 30 min. The limit of agreement for PO2 also narrowed over time (± 23.1 mmHg at 30 min). Subgroup analyses showed that the PaCO2 and PaO2 levels, gender, and younger age significantly affected the biases. All hypercapnia subjects with PaCO2 > 50 mmHg (n = 13) showed PtcCO2 ≥ 50 mmHg for until 12 min. CONCLUSIONS: Although PtcCO2 is useful, it cannot completely replace PaCO2 because PCO2 occasionally showed large bias. On the other hand, the prediction of PaO2 using PtcO2 was unrealistic in Asian adults. PtcCO2 ≥ 50 mmHg for until 12 min can be used as a screening tool for severe hypercapnia with PaCO2 > 50 mmHg.

Auto-antibody evaluation in idiopathic interstitial pneumonia and worse survival of patients with Ro52/TRIM21auto-antibody.

Some patients with interstitial pneumonia (IP) have auto-antibodies, but do not fit the criteria for specific connective tissue diseases. Examination of auto-antibodies is recommended for diagnosis idiopathic pulmonary fibrosis. A prospective cohort study was performed in 285 patients with IP. Eleven auto-antibodies were assessed and patients were followed for 2 years. All 285 patients underwent the myositis panel test (MPT) for 11 auto-antibodies. Among them, 23.5% (67/285) of the patients had a positive MPT and 14.7% (42/285) had connective tissue diseases. Among the 49 MPT positive patients without connective tissue diseases, 29 patients (59.2%) were positive for Ro52, including 17 patients with Ro52 mono-positivity. Among interstitial pneumonia patients without connective tissue diseases, the Ro52 mono-positive patients showed worse at 2-years survival than those who were Ro52 negative (p = 0.022, HR = 5.88, 95% CI 1.29-26.75). Most of the Ro52 positive patients also showed a low titer of anti-nucleolar antibody. About 20% of IP patients had auto-antibodies detectable by the MPT, and Ro52 positive patients accounted for more than half of the MPT positive patients without connective tissue diseases. Detection of Ro52 auto-antibodies may be useful for assessing the risk of progression in idiopathic interstitial pneumonia patients without connective tissue diseases and a low anti-nucleolar antibody titer.

Comparison of inducible nitric oxide synthase mRNA expression in different airway portions and association with nitric oxide parameters from patients with asthma.

BACKGROUND: Fractional exhaled nitric oxide concentration (FeNO) is widely used to support diagnosis and monitoring of bronchial asthma (BA). Tsoukias and George proposed a two-compartment model (2CM) for assessing the alveolar concentration of NO, referred to as CANO(2CM), while Condorelli et al proposed a model based on the trumpet shape of the airway tree and axial diffusion (TMAD), referred to as CANO(TMAD). In addition, Högman et al proposed non-linear model, referred to as CANO(non-linear). OBJECTIVE: We examined associations between the expression of inducible nitric oxide synthase (iNOS) mRNA in airway cells (ACs) by bronchoscopy and NO-parameters calculated by the three methods and identified which of them accurately reflected expression of iNOS mRNA from different airway portions. METHODS: We retrospectively analysed data of 18 patients with stable, mild-moderate asthma, including 10 steroid-naïve BA (snBA) patients. Samples were obtained from airway brushings and bronchoalveolar lavage (BAL). Expressions of iNOS protein in tissue samples were evaluated by immunostaining. The iNOS mRNA in ACs was measured by qPCR. NO-parameters calculated by the three methods above and evaluated whether they were associated with iNOS mRNA in ACs derived from proximal (2nd carina), distal (10-15th) airways and alveolar regions. RESULTS: Immunostaining revealed expression of iNOS proteins mainly in epithelial cells in the airways, while it was mainly expressed in macrophages in the alveolar region in the snBA group. The iNOS mRNA expression was increased in both proximal and distal ACs in the snBA group compared with steroid-treated BA group (stBA). CANO(2CM) negatively associated with FEV1 (%predicted) and also associated with iNOS mRNA in distal ACs significantly. However, CANO(TMAD) and CANO(non-linear) showed no correlation with lung function nor iNOS mRNA expression in any portions of ACs. CONCLUSIONS: These results suggested that CANO(2CM) reflected distal airway inflammation in steroid-naïve asthma.

Development of xenogeneic decellularized biotubes for off-the-shelf applications.

In earlier studies, we developed in vivo tissue-engineered, autologous, small-caliber vascular grafts, called "biotubes," which withstand systemic blood pressure and exhibit excellent performance as small-caliber vascular prostheses in animal models. However, biotube preparation takes 4 weeks; therefore, biotubes cannot be applied in emergency situations. Moreover, for responses to various types of surgery, grafts should ideally be readily available in advance. The aim of this study was to develop novel, off-the-shelf, small-caliber vascular grafts by decellularizing in vivo tissue-engineered xenogeneic tubular materials. Silicone rod molds (diameter: 2 mm, length: 70 mm) placed in subcutaneous pouches of a beagle dog for 4 weeks were harvested with their surrounding connective tissues. Tubular connective tissues were obtained after pulling out the impregnated molds. Subsequently, they were decellularized by perfusion with sodium dodecyl sulfate and Triton X-100. They were stored as off-the-shelf grafts at -20°C for 1 week. The decellularized grafts derived from the beagle dog were xenogeneically transplanted to the abdominal aortas of rats (n = 3). No signs of abnormal inflammation or immunological problems due to the xenogeneic material were observed. Echocardiography confirmed the patency of the grafts at 1 month after implantation. Histological evaluation revealed that the grafts formed neointima on the luminal surface, and that the graft walls had cell infiltration. Little accumulation of CD68-positive macrophages in the graft wall was observed. Xenogeneic decellularized tubular tissues functioned as small-caliber vascular grafts, as well as autologous biotubes. This technology enables the easy fabrication of grafts from xenogeneic animals in advance and their storage for at least a week, satisfying the conditions for off-the-shelf grafts.

Matrix-assisted laser desorption/ionization imaging mass spectrometry reveals changes of phospholipid distribution in induced pluripotent stem cell colony differentiation.

Induced pluripotent stem cells (iPSCs) are opening up new possibilities for medicine. Understanding the regulation of iPSC biology is important when attempting to apply these cells to disease models or therapy. Changes of lipid metabolism in iPSCs were investigated by matrix-assisted laser desorption/ionization time-of-flight imaging mass spectrometry (MALDI-TOF-IMS). Analysis revealed changes of the intensity and distribution of peaks at m/z 782.5 and 798.5 in iPSC colonies during spontaneous differentiation. Two phosphatidylcholines (PCs) were identified: C44H81NO8P, PC(36:4)[M+H]+ at m/z 782.5 and C42H82NO8P, PC(34:1)[M+K]+ at m/z 798.5. The intensity of PC(36:4) showed an inverse relation between undifferentiated and differentiated iPSC colonies. PC(34:1) displayed a diffuse distribution in undifferentiated iPSC colonies, while it showed a concentric distribution in differentiated iPSC colonies, and was localized at the border of the differentiated and undifferentiated areas or the border between undifferentiated iPSC and feeder cells. These findings suggested that the distribution of lipids changes during the growth and differentiation of iPSCs and that MALDI-TOF-IMS was useful for analyzing these changes. PC(36:4) might play a role in maintaining pluripotency, while PC(34:1) might play a role in the differentiation and spread of iPSCs. Graphical Abstract MALDI Imaging for phosphatidylcholine distribution changes during sponteneous differentiaton of induced pluiripotent stem cells colonies.

Dipeptidyl peptidase-4 is highly expressed in bronchial epithelial cells of untreated asthma and it increases cell proliferation along with fibronectin production in airway constitutive cells.

BACKGROUND: Type 2 helper T-cell cytokines including IL-13 play a central role in the pathogenesis of bronchial asthma (BA). During the course of our research, our attention was drawn to dipeptidyl peptidase-4 (DPP4) as one of the molecules that were induced from bronchial epithelial cells (BECs) by IL-13 stimulation. DPP4 could become a new biomarker or therapeutic target. The aim of this study was to investigate the expression of DPP4 in the asthmatic airway, and its role in the pathophysiology of asthma. METHODS: BECs were isolated from patients with inhaled corticosteroid-treated asthma (stBA) and inhaled corticosteroid-naïve asthma (snBA) using bronchoscopy. DPP4 mRNA expression in freshly isolated BECs and primary cultured BECs with or without IL-13 stimulation was investigated by microarray analysis and quantitative real-time PCR (qPCR). The distribution of DPP4 protein was determined by immunostaining of transbronchial lung biopsy specimens from asthma patients. The effect of recombinant human (rh) DPP4 on the proliferation of lung fibroblasts (HFL-1) and bronchial smooth muscle cells (BSMCs) was examined, as well as its effect on the production of fibronectin (FN). RESULTS: DPP4 mRNA was strongly expressed in freshly isolated BECs in snBA, and its expression was significantly enhanced by IL-13 stimulation. DPP4 mRNA expression in BECs of snBA significantly correlated with exhaled nitric oxide. Biopsied tissues of the asthmatic airway revealed strong expression of DPP4 protein in BECs from snBA subjects. rhDPP4 stimulated the proliferation of HFL-1 and BSMCs, and it also enhanced production of FN from these airway cells. CONCLUSION: DPP4 may be involved in the pathologic features of asthmatic airway inflammation and cell proliferation and FN production.

Perioperative care with fast-track management in patients undergoing pancreaticoduodenectomy.

BACKGROUND: It has been considered that allowing patients to return to daily life earlier after surgery helps recovery of physiological function and reduces postoperative complications and hospital stay. We investigated the usefulness of fast-track management in perioperative care of patients undergoing pancreaticoduodenectomy (PD). METHODS: Patients (n = 90) who received conventional perioperative management from 2005 to 2009 were included as the 'conventional group' (historical control group), and patients who received perioperative care with fast-track management (n = 100) from 2010 to March 2013 were included as the 'fast-track group'. To evaluate the efficacy of perioperative care with fast-track management, the incidence of postoperative complications and the length of hospital stay were compared between the two groups (comparative study). For statistical analysis, univariate analysis was performed using the χ (2) test or Fisher's exact test. RESULTS: There was no significant difference between the two groups in sex, mean age, presence/absence of diabetes mellitus, preoperative drainage for jaundice, previous disease, operative procedure, mean duration of operation, or blood loss (p < 0.01). The incidence of surgical site infection in the conventional group and fast-track group was 28.9 and 14.0 %, respectively, with a significant difference between the two groups (p = 0.019). In addition, the incidence of pancreatic fistula (grade B, C) significantly differed between the two groups (27.8 % in the conventional group, 9.0 % in the fast-track group; p = 0.001). The mean postoperative hospital stay was 36.3 days in the conventional group and 21.9 days in the fast-track group (p < 0.001). CONCLUSIONS: Perioperative care with fast-track management may reduce postoperative complications and decrease the length of hospital stay in patients undergoing PD.

Endovascular repair of traumatic aortic injury using a modified, commercially available endograft to preserve aortic arch branches.

A 25-year-old woman was admitted to our hospital after being involved in a high-speed motorcycle accident. Computed tomography angiography revealed a blunt traumatic aortic injury of the lesser curvature of the distal aortic arch accompanied by splintered fractures of the seventh thoracic vertebra and left clavicle. If the pseudoaneurysm had been treated with open surgical repair, then arch replacement under cardiopulmonary bypass, which was considered to be too invasive, would have been necessary. Therefore, thoracic endovascular aortic repair (TEVAR) was preferred as a first-line treatment to prevent pulmonary complications and hemorrhaging. Because the proximal landing zone for TEVAR was insufficient, we used a modified (fenestrated) commercially available endograft to preserve the branches of the aortic arch. Postoperative computed tomography scans confirmed that the pseudoaneurysm had been excluded without the endoleaks, and the aortic arch branches were patent. The patient's postoperative course was uneventful, and she was discharged from the hospital to have surgery for a vertebral fracture on postoperative day 6.

Anatomic variations of hepatic artery and new clinical classification based on abdominal angiographic images of 1200 cases.

BACKGROUND/AIMS: There is wide variation in the branches of the hepatic artery. We aimed to classify these variations clinically on the basis of abdominal angiographic images in order to find out the suitable classification. METHODOLOGY: Anatomic variations of the hepatic artery of 1200 patients were analyzed at Tokyo Women's Medical University from 2000 to 2010, and Classified into four categories: "Y", "I-I", "Y plus I", and "I-I plus I". Patients with a proper hepatic artery were categorized as "Y", and those without as "I-I", to describe the arteries morphologically. We denoted an accessory artery as "I", and described it as being to the left or right of "Y"; i.e., "I, Y" or "Y, I", respectively. RESULTS: Normal hepatic anatomy was observed in 77.2% (926 subjects), and variations were found in 22.8% (274 subjects). Of all the patients, 3.8% (45 subjects) could not be classified using Michels' classification. On the other hand, when variations were classified using our classification, all variations could be classified into either Category Y (85.6%, 1027 subjects) or Category I-I (14.4%, 173 subjects). CONCLUSIONS: Our simplified new clinical classification of hepatic artery variants would be useful for preoperative planning in hepato-biliary-pancreatic surgery and liver transplantation.

Implantation study of small-caliber "biotube" vascular grafts in a rat model.

We developed autologous vascular grafts, called "biotubes," by simple and safe in-body tissue architecture technology, which is a practical concept of regenerative medicine, without using special sterile conditions or complicated in vitro cell treatment processes. In this study, biotubes of extremely small caliber were first auto-implanted to rat abdominal aortas. Biotubes were prepared by placing silicone rods (outer diameter 1.5 mm, length 30 mm) used as a mold into dorsal subcutaneous pouches in rats for 4 weeks. After argatroban coating, the obtained biotubes were auto-implanted to abdominal aortas (n = 6) by end-to-end anastomosis using a custom-designed sutureless vascular connecting system under microscopic guidance. Graft status was evaluated by contrast-free time-of-flight magnetic resonance angiography (TOF-MRA). All grafts were harvested at 12 weeks after implantation. The patency rate was 66.7 % (4/6). MRA showed little stenosis and no aneurysmal dilation in all biotubes. The original biotube had wall thickness of about 56.2 ± 26.5 µm at the middle portion and mainly random and sparse collagen fibers and fibroblasts. After implantation, the wall thickness was 235.8 ± 24.8 µm. In addition, native-like vascular structure was regenerated, which included (1) a completely endothelialized luminal surface, (2) a mesh-like elastin fiber network, and (3) regular circumferential orientation of collagen fibers and α-SMA positive cells. Biotubes could be used as small-caliber vascular prostheses that greatly facilitate the healing process and exhibit excellent biocompatibility in vascular regenerative medicine.

Development of a completely autologous valved conduit with the sinus of Valsalva using in-body tissue architecture technology: a pilot study in pulmonary valve replacement in a beagle model.

BACKGROUND: We developed autologous prosthetic implants by simple and safe in-body tissue architecture technology. We present the first report on the development of autologous valved conduit with the sinus of Valsalva (BIOVALVE) by using this unique technology and its subsequent implantation in the pulmonary valves in a beagle model. METHODS AND RESULTS: A mold of BIOVALVE organization was assembled using 2 types of specially designed silicone rods with a small aperture in a trileaflet shape between them. The concave rods had 3 projections that resembled the protrusions of the sinus of Valsalva. The molds were placed in the dorsal subcutaneous spaces of beagle dogs for 4 weeks. The molds were covered with autologous connective tissues. BIOVALVEs with 3 leaflets in the inner side of the conduit with the sinus of Valsalva were obtained after removing the molds. These valves had adequate burst strength, similar to that of native valves. Tight valvular coaptation and sufficient open orifice area were observed in vitro. These BIOVALVEs were implanted to the main pulmonary arteries as allogenic conduit valves (n=3). Postoperative echocardiography demonstrated smooth movement of the leaflets with trivial regurgitation. Histological examination of specimens obtained at 84 days showed that the surface of the leaflet was covered by endothelial cells and neointima, including an elastin fiber network, and was formed at the anastomosis sides on the luminal surface of the conduit. CONCLUSIONS: We developed the first completely autologous BIOVALVE and successfully implanted these BIOVALVEs in a beagle model in a pilot study.

A life-saving case of cardiopulmonary arrest with cardiac tamponade caused by erosion 6 years after percutaneous atrial septal defect closure: a case report.

BACKGROUND: Cardiac erosion after percutaneous atrial septal defect (ASD) closure is a rare complication that requires immediate life-saving emergency surgery. In this report, we present our successful life-saving strategy for cardiac arrest due to cardiac tamponade caused by erosion 6 years after the percutaneous closure of an ASD. CASE PRESENTATION: The patient was a 50-year-old man who received treatment using an Amplatzer septal occluder (St. Jude Medical, St. Paul, MN, USA) treatment for ostium secundum atrial septal defect (size: 29.5 × 27.0 mm) at another institution when he was 44 years old. CONCLUSIONS: This case report presents a bailout surgical strategy for patients who are hemodynamically unstable with risks of coagulopathy and multiple organ failure. This case shows that cardiac surgeons need to be aware of percutaneous ASD-closure complications and should consider a bailout surgical strategy for patients at risk of multiple organ failure.

One-stage surgery for type A aortic dissection and iliac artery aneurysm rupture.

We present a patient with Stanford type A aortic dissection with malperfusion of the left kidney and lower extremity, and rupture of a common iliac artery aneurysm. After establishing lower extremity reperfusion using a percutaneous femorofemoral shunt in the emergency room, simultaneous open aortic arch repair and open abdominal aorta repair were performed. Our approach allowed concomitant repair of proximal dissection, limb ischemia, and iliac artery aneurysm rupture, all of which are critical predictors of mortality.

Effects of a calcium-channel blocker (CV159) on hepatic ischemia/reperfusion injury in rats: evaluation with selective NO/pO2 electrodes and an electron paramagnetic resonance spin-trapping method.

Nitric oxide (NO) and the partial pressure of oxygen (pO(2)) in the liver were simultaneously quantified in rats with partial hepatic ischemia/reperfusion injury (PHIRI). Real-time NO/pO(2) monitoring and immunohistochemical analysis for superoxide dismutase and inducible nitric oxide synthase (iNOS) and endothelial NOS (eNOS) were performed to evaluate the protective effects of a dihydropyridine-type calcium-channel blocker--CV159--on PHIRI. Serum high-mobility-group box-1 (HMGB-1) was measured to assess cellular necrosis. Moreover, we used in vitro/ex vivo electron paramagnetic resonance spin trapping to assess the hydroxyl radical (*OH)-scavenging activity (OHSA) of CV159 and the liver tissue. The NO levels were significantly higher in CV159-treated rats than in control rats throughout the ischemic phase. Immediately after reperfusion, the levels temporarily increased in waves and then gradually decreased in the treated rats but remained constant in the control rats. pO(2) was continually higher in the treated rats. In these rats, hepatic eNOS expression increased, whereas iNOS expression decreased. The treated rats exhibited significantly higher cytosolic and mitochondrial concentrations NOx (NO(2)+NO(3)). The serum HMGB-1 levels significantly decreased in the treated rats. Moreover, CV159 directly scavenged *OH and both mitochondrial and cytosolic OHSA were preserved in the treated rats. Thus, CV159-mediated inhibition of intracellular Ca(2+) overloading may effectively minimize organ damage and also have *OH-scavenging activity and the cytoprotective effects of eNOS-derived NO.

Preparation of in-vivo tissue-engineered valved conduit with the sinus of Valsalva (type IV biovalve).

A novel autologous valved conduit with the sinus of Valsalva-defined as a type IV biovalve-was created in rabbits by "in-body tissue-architecture" technology with a specially designed mold for the valve leaflets and the sinus of Valsalva and a microporous tubular scaffold for the conduit. The mold included 2 rods composed of silicone substrates. One was concave shaped, with 3 projections resembling the sinus of Valsalva; the other was convex shaped. The connection between the rods was designed to resemble the closed form of a trileaflet valve. The 2 rods were connected with a small aperture of 500-800 microm, which bound membranous connective tissue obtained from the dorsal subcutaneous layer of a rabbit. The rods were placed in a polyurethane scaffold that had many windows in its center. Both ends of the scaffold were tied with thread for fixation, and this assembly was embedded for 1 month in a subcutaneous pouch in the same Japanese white rabbit from which the connective tissue was obtained. After 1 month, all the surfaces of the implant were found to be completely covered with newly developed connective tissue. The substrates were removed from both sides of the harvested cylindrical implant, and homogenous well-balanced trileaflet-shaped membranous tissue was found inside the developed conduit with 3 protrusions resembling the sinus of Valsalva. The trileaflet valve closed and opened rapidly in synchrony with the backward and forward flow of a pulsatile flow circuit in vitro.

Mixed acinar-endocrine carcinoma of the pancreas with intraductal growth into the main pancreatic duct: Report of a case.

The patient was a 75-year-old asymptomatic man, in whom a tumor mass in the pancreatic tail had been found 6 months earlier. Computed tomography revealed a mass 7 cm in diameter, and an enhancement with contrast medium was observed at the periphery and partially inside the mass, but not in most parts of the tumor. Endoscopic retrograde cholangiopancreatography showed a filling defect in the main pancreatic duct. A distal pancreatectomy was performed because of the possibility of a malignant tumor. The tumor consisted of a lobular invasive growth component and a component with intraductal growth into the main pancreatic duct, and histologically the tumor cells had solid acinar to partially trabecular/tubular patterns. Trypsin (an acinic cell marker) expression was widely observed, followed by the expression of chromogranin A (an endocrine cell marker) in about 30% of the tumor cells. The tumor was diagnosed as mixed acinar-endocrine carcinoma according to the WHO classification.

Histology and Mechanics of In Vivo Tissue-Engineered Vascular Graft for Children.

PURPOSE: This study sought to evaluate the histologic and mechanical properties of autologous in vivo tissue-engineered vascular grafts (in vivo TEVGs) used for pediatric heart surgery. DESCRIPTION: Molds of in vivo TEVGs made of silicone drain tubes were embedded into subcutaneous spaces in 2 boys during their first operation and were used as patch materials to treat pulmonary artery stenosis during the second operation. The remaining pieces of the patches were evaluated histologically and mechanically. EVALUATION: In vivo TEVGs had very smooth luminal surfaces, and their walls mainly comprised collagen fibers and small numbers of fibroblasts. Mean wall thickness was 200 µm, mean suture retention strength was 2.26 N, and burst pressure was 3057 mm Hg. CONCLUSIONS: Human in vivo TEVGs mainly comprise collagen fibers, and their mechanical properties prove them safe for pulmonary arterioplasty. Therefore, human in vivo TEVGs may be promising alternatives to autologous pericardium for pediatric cardiovascular surgical procedures that often require multistage operations.

Second surgery after a pancreaticoduodenectomy in patients with periampullary malignancies.

BACKGROUND/AIMS: Few case reports have previously documented a second surgery after pancreaticoduodenectomy due to recurrence or other reasons in patients with periampullary malignancies. The present report summarized the experience of this clinic with secondary surgery after Pancreaticoduodenectomy (PD). METHODOLOGY: During the past 7 years, 7 out of 95 patients with periampullary malignancies underwent a second surgery after pancreaticoduodenectomy at this institution. The clinical courses of these patients are presented and 2 interesting cases are shown in the present study. RESULTS: One patient with lower bile duct adenocarcinoma underwent a remnant splenopancreatectomy due to pancreatic recurrence 36 months after pancreaticoduodenectomy. The other patient with lower bile duct adenocarcinoma underwent a hepatectomy due to a solitary liver metastasis 47 months after a pancreaticoduodenectomy. These 2 patients have survived 4 and 13 months after the second surgery. In the 7 patients requiring secondary surgery, 5 underwent the procedure due to recurrent disease, and 4 of the 5 received the second surgery to remove the lesion. The mean interval between pancreaticoduodenectomy and the second operation was 32 months in the 5 patients with recurrent disease and 27 months in the all 7 patients. One of the 5 patients died of recurrent disease only 5 months after the second procedure because the surgery was a palliative bypass. However, the other 3 survived more than 1 year after the resection of the lesion at the recurrent site. CONCLUSIONS: The present study reports 2 rare cases with lower bile duct adenocarcinoma in which a recurrent tumor was removed after pancreaticoduodenectomy. In this study, 4 patients undergoing a curative re-operation survived more than 1 year after the surgery. The present study was small, but the findings are significant because of the scarcity of reports of patients undergoing secondary surgery after PD.

Prophylactic irrigation around a pancreaticojejunostomy for the treatment of a pancreatic fistula after a pancreaticoduodenectomy in patients with a risky pancreatic remnant.

BACKGROUND/AIMS: Postoperative morbidity after a pancreaticoduodenectomy remains high mainly due to pancreatic fistula, but effective methods to prevent the development of pancreatic fistula have yet to be established. The present study prospectively investigated whether postoperative prophylactic irrigation around the pancreaticojejunostomy might be able to prevent eventual pancreatic fistula and infectious complications after a pancreaticoduodenectomy. METHOD: Among 75 patients undergoing a pancreaticoduodenectomy between 2003 and 2005, 50 patients in whom the drain amylase level on postoperative day 1 were 1,500 IU/L or more were selected for the present study. Twenty-six of the 50 patients underwent postoperative prophylactic 72-hour continuous irrigation around the pancreaticojejunostomy starting from postoperative day 1 (Irrigation group). On the other hand, 24 of them did not undergo such irrigation (Non-irrigation group). The incidence of pancreatic fistula, infectious complications, delayed gastric emptying, and the length of hospital stay were then compared between the 2 groups. RESULTS: The incidences of pancreatic fistula, wound infection, drain infection, sepsis, delayed gastric emptying, overall morbidity, and length of hospital stay were found to be significantly less in the irrigation group than in the non-irrigation group. CONCLUSIONS: Prophylactic irrigation may possibly be able to prevent the occurrence of pancreatic fistula and infectious complications after a pancreaticoduodenectomy in patients with a risky pancreatic remnant.