The purpose of this study was to estimate the possibilities of an acellular matrix using a modified acellularization protocol, which circumvents immunological, microbiological, and physiological barriers. We treated porcine subclavian arteries with various reagents to construct acellular grafts. Afterwards, these grafts were interposed in a mongrel dogs' abdominal aorta. Six dogs underwent interposition with fresh porcine grafts (control group), and seven had interposed acellular grafts (acellular group). The control and acellular group dogs were sacrificed at 1, 3, 5 (n=2 in each group) and 12 months (n=1 in acellular group) after the operation. Histopathological examinations were then performed, to assess the degree to which re-endothelialization, inflammation, thrombus formation, and calcification occurred. The entire acellular group, but none of the control group, exhibited re-endothelialization. The degrees to which inflammation, thrombosis, and calcification occurred were found to be lower in the acellular group. We also discovered many smooth muscle cells in the medial layer of the xenograft that had been implanted in the dog sacrificed 12 months after the operation. These results suggest that the construction of xenografts using our modified acellularization protocol may offer acceptable outcomes as a vascular xenograft.
Transplantation, Heterologous/*methods ; Tissue Engineering/*methods ; Swine ; Subclavian Artery/*cytology/*transplantation ; Graft Survival/*physiology ; Dogs ; Cell-Free System/*transplantation ; Animals

The event-free survival (EFS) for pediatric acute lymphoblastic leukemia (ALL) has shown remarkable improvement in the past several decades. In Korea also, a recent study showed 10-year EFS of 78.5%. Much of the improved outcome for pediatric ALL stems from the accurate identification of prognostic factors, the designation of risk group based on these factors, and treatment of appropriate duration and intensity according to risk group, done within the setting of cooperative clinical trials. The schema of first-line therapy for ALL remains mostly unchanged, although many groups have now reported on the elimination of cranial irradiation in all patients with low rates of central nervous system relapse. Specific high risk subgroups, such as Philadelphia chromosome-positive (Ph+) ALL and infant ALL continue to have significantly lower survival than other ALL patients. The introduction of tyrosine kinase inhibitors into therapy has led to enhanced outcome for Ph+ ALL patients. Infant ALL patients, particularly those with MLL rearrangements, continue to have poor outcome, despite treatment intensification including allogeneic hematopoietic cell transplantation. Relapsed ALL is a leading cause of mortality in pediatric cancer. Recent advances in immunotherapy targeting the CD19 of the ALL blast have shown remarkable efficacy in some of these relapsed and refractory patients. With improved survival, much of the current focus is on decreasing the long-term toxicities of treatment.
Cell Transplantation ; Central Nervous System ; Child ; Cranial Irradiation ; Disease-Free Survival ; Humans ; Immunotherapy ; Infant ; Korea ; Mortality ; Precursor Cell Lymphoblastic Leukemia-Lymphoma* ; Protein-Tyrosine Kinases ; Recurrence ; Transplants

AIMTo examine whether the existence of the donor-and recipient-derived DNA chimerism in recipient's plasma can be a predictive marker for the status of transplanted organ.

METHODSOne hundred and twenty-six female patients who had been transplanted with male kidneys were enrolled in the present study. In these female recipients, the SRY(1), DYZ(1)(1st) and DYZ(1)(2nd) genes on the Y chromosome from the plasma were prospectively examined using reverse transcription polymerase chain reaction (RT-PCR).

RESULTSSRY, DYZ(1)(1st) and DYZ(1)(2nd) sequences were detected in the cell-free blood (plasma) of 97 (77%) of 126 female patients with male kidney. The average time that the transplanted kidneys functioned was 8.7 years and 5.4 years among microchimerism-positive and microchimerism-negative recipients, respectively. The frequency of the patients who had acute rejection after renal transplantation was approximately 10% and 28% in microchimerism-positive and microchimerism-negative recipients, respectively. Serum creatinine levels in microchimerism-positive patients were significantly lower than those in microchimerism-negative patients.

CONCLUSIONThese results suggest that plasma DNA microchimerism present in certain patients following renal transplantation and measurement of plasma DNA microchimerism using quantitative RT-PCR might be a useful predictor for the acceptance of transplanted kidneys.

Base Sequence ; Blood ; Cell-Free System ; Chimera ; Chromosomes, Human, Y ; DNA ; genetics ; DNA Primers ; Female ; Humans ; Kidney Transplantation ; Male ; Reproducibility of Results ; Reverse Transcriptase Polymerase Chain Reaction ; Sensitivity and Specificity ; Sex Factors ; Tissue Donors ; Treatment Outcome

OBJECTIVE: To improve the hemocompatibility of decellular vascular matrix via heparin-iron complex multilayers (HICMs) nanomodification. METHODS: A novel thrombo-resistant surface for decellular xenograft was developed by alternating linkage of dihydroxy-iron and heparin to decellular bovine jugular vein (DC-BJV), and its surface characterization, biomechanical stability and hemocompatibility were detected by scanning electron microscopy, tensile test and hemocompatibility evaluation, respectively. RESULTS: A toluidine blue colorimetric method indicated the amount of linked heparin was about (808±86) μg/cm2 per assembly-cycle. Scanning electron microscopic (SEM) images proved that HICMs were uniformly linked to and formed nanoscale films around the fibrils of DC-BJV. Toluidine blue staining histologic images showed that HICMs were linked mainly to DC-BJV surfaces. Washing test showed that the release of heparin was (281±43), (422 ± 60), (729±81), (1053±116), (1317±157), (1618±187) and (1945 ± 268 ) μg/cm(2) at 1 day, 1, 2, 3, 4, 6 and 8 week washing, respectively. Tensile tests showed an increased biomechanical stability. Hemocompatibility evaluations showed that PT and APTT of all the trial groups were above the normal reference ranges and that mean platelet count per 10000 μm2 area was 8±4 for HICMs layer-by-layer modified BJV (LBL-BJV) vs 48±16 for DC-BJV. CONCLUSION HICMs are firmly linked to DC-BJV, and can form nanoscale thrombo-resistant films, which yield a sustained release of heparin. HICMs nanomodification improves the hemocompatibility of decellular xenograft.
Animals ; Biocompatible Materials ; Blood Vessel Prosthesis ; Cattle ; Cell-Free System ; Coated Materials, Biocompatible ; chemical synthesis ; chemistry ; pharmacology ; Heparin ; administration & dosage ; chemistry ; Iron ; administration & dosage ; chemistry ; Jugular Veins ; Nanostructures ; chemistry ; ultrastructure ; Surface Properties ; Tissue Scaffolds ; Transplantation, Heterologous

This retrospective study investigated the clinical characteristics and outcomes of second malignant neoplasms (SMNs) in survivors of childhood cancer from multiple institutions in Korea. A total of 102 patients from 11 institutions who developed SMN after childhood cancer treatment between 1998 and 2011 were retrospectively enrolled. The most common primary malignant neoplasms (PMNs) were central nervous system (CNS) tumors (n = 17), followed by acute lymphoblastic leukemia (n = 16), non-Hodgkin lymphoma (n = 13), and osteosarcoma (n = 12). The most common SMNs were therapy-related myeloid neoplasms (t-MNs; acute myeloid leukemia [AML], 29 cases; myelodysplastic syndrome [MDS], 12 cases), followed by thyroid carcinomas (n = 15) and CNS tumors (n = 10). The median latency period was 4.9 years (range, 0.5-18.5 years). Among 45 patients with solid tumors defined as an SMN, 15 (33%) developed the lesion in a field previously subjected to radiation. The 5-year overall survival (OS) rate of patients with an SMN was 45% with a median follow-up time of 8.6 years. Patients with AML, MDS, and CNS tumors exhibited the poorest outcomes with 5-year OS rates of 18%, 33%, and 32%, respectively, whereas those with second osteosarcoma showed comparable outcomes (64%) to patients with primary counterpart and those with second thyroid carcinoma had a 100% OS rate. Further therapeutic efforts are recommended to improve the survival outcomes in patients with SMNs, especially in cases with t-MNs and CNS tumors.
Adolescent ; Antineoplastic Agents/therapeutic use ; Central Nervous System Neoplasms/diagnosis/drug therapy/radiotherapy ; Child ; Child, Preschool ; Disease-Free Survival ; Hospitals ; Humans ; Infant ; Leukemia, Myeloid, Acute/diagnosis/epidemiology/mortality/therapy ; Myelodysplastic Syndromes/diagnosis/epidemiology/mortality/therapy ; Neoplasms, Second Primary/*diagnosis/epidemiology/mortality/therapy ; Osteosarcoma/diagnosis/epidemiology ; Retrospective Studies ; Stem Cell Transplantation ; Survival Rate ; Transplantation, Autologous ; Young Adult

This retrospective study investigated the clinical characteristics and outcomes of second malignant neoplasms (SMNs) in survivors of childhood cancer from multiple institutions in Korea. A total of 102 patients from 11 institutions who developed SMN after childhood cancer treatment between 1998 and 2011 were retrospectively enrolled. The most common primary malignant neoplasms (PMNs) were central nervous system (CNS) tumors (n = 17), followed by acute lymphoblastic leukemia (n = 16), non-Hodgkin lymphoma (n = 13), and osteosarcoma (n = 12). The most common SMNs were therapy-related myeloid neoplasms (t-MNs; acute myeloid leukemia [AML], 29 cases; myelodysplastic syndrome [MDS], 12 cases), followed by thyroid carcinomas (n = 15) and CNS tumors (n = 10). The median latency period was 4.9 years (range, 0.5-18.5 years). Among 45 patients with solid tumors defined as an SMN, 15 (33%) developed the lesion in a field previously subjected to radiation. The 5-year overall survival (OS) rate of patients with an SMN was 45% with a median follow-up time of 8.6 years. Patients with AML, MDS, and CNS tumors exhibited the poorest outcomes with 5-year OS rates of 18%, 33%, and 32%, respectively, whereas those with second osteosarcoma showed comparable outcomes (64%) to patients with primary counterpart and those with second thyroid carcinoma had a 100% OS rate. Further therapeutic efforts are recommended to improve the survival outcomes in patients with SMNs, especially in cases with t-MNs and CNS tumors.
Adolescent ; Antineoplastic Agents/therapeutic use ; Central Nervous System Neoplasms/diagnosis/drug therapy/radiotherapy ; Child ; Child, Preschool ; Disease-Free Survival ; Hospitals ; Humans ; Infant ; Leukemia, Myeloid, Acute/diagnosis/epidemiology/mortality/therapy ; Myelodysplastic Syndromes/diagnosis/epidemiology/mortality/therapy ; Neoplasms, Second Primary/*diagnosis/epidemiology/mortality/therapy ; Osteosarcoma/diagnosis/epidemiology ; Retrospective Studies ; Stem Cell Transplantation ; Survival Rate ; Transplantation, Autologous ; Young Adult