In this brief review, some key issues related to cryopreservation of seeding cells, scaffolds, and engineered tissues are outlined. The importance of cryopreservation technology to the research and development of tissue engineered products is demonstrated. The biological or biochemical reaction rate must be reduced or completely shut off in order to preserve the tissue engineered products for a long period of time. Cryopreservation may be one of the possible approaches to the fulfillment of this requirement. Seeding cells are stored at low temperature. Tissue engineered scaffold products are usually lyophilized. Engineered tissues are preserved by vitreous cryopreservation technology.
Cell Count ; Cell Survival ; Cryopreservation ; methods ; Humans ; Tissue Engineering ; Tissue Preservation ; Tissue Survival

The purpose of this study was to investigate the cytotoxicity of orthodontic bands in vitro and in vivo.4 types of orthodontic bands were applied to cultured fibroblast and the supermatants were injected into dorsal subcutaneous tissue of mice. In vitro, the cytotoxixity was evaluated by an MTT assay after 2 and 6days.In vivo, the histopathologic observation was performed 2 days after injection. The results were: 1. The cell viability was significantly decreased in the group added phosphoric acid in comparison to control group, but there was not any significance among the experimental group after 2 days. 2. Cell viability decreased in the high Ni containing group after 6 days. 3. The histopathological finding was that the Cr-containing group showed severe infiltration of inflammatory cells and muscular destruction.
Animals ; Cell Survival ; Fibroblasts ; Mice ; Subcutaneous Tissue

The perichondrium has neochondrogenic potential. Many authors have published their study for the cartilage regeneration from perichondrium and the clinical uses of perichondrial graft. How is the difference of thickness of the regenerated cartilage after crushing the free perichondrial graft, compare with uncrushed graft? In this study, the perichondrium was obtained from rabbit, ears, and sectioned 10x10 mm slices. The uncrushed and crushed perichondriums were grafted into subcutaneous layer of back. After the 2,4 and 8 weeks, authors obtained regenerated cartilage from both crushed and uncrushed free perichondrial graft from rabbit back, examined the survival rate and thickness by histologic study.The results are as follows: 1. The survival rate was no difference between the uncrushed perichondrium & crushed perichondrium (p>0.05). 2. The cartilage from the uncrushed perichondrium was thicker than the crushed perichondrium, at only 8 weeks(p<0.01). 3. The thickness of regenerated cartilage was similar to the cartilage of the donor site of free perichondrial graft at 4 weeks(p>0.05).
Cartilage* ; Ear* ; Humans ; Regeneration* ; Survival Rate ; Tissue Donors ; Transplants

Based on a review of the literature, this paper provides an update on surgical treatment of middle and low rectal cancer and discusses issues of debate surrounding that treatment. The main goal of the surgical treatment of rectal cancer is radical resection of the tumor and surrounding lymphatic tissue. Local excision of early rectal cancer can be another treatment option, in which the patient can avoid possible complications related to radical surgery. Neoadjuvant chemoradiation therapy (CRT) has been recommended for patients with cT3-4N0 or any T N+ rectal cancer because CRT shows better local control and less toxicity than adjuvant CRT. However, recent clinical trials showed promising results for local excision after neoadjuvant CRT in selected patients with low rectal cancer. In addition, the "wait and see" concept is another modality that has been reported for the management of tumors that show complete clinical remission after neoadjuvant CRT. Although radical surgery for middle and low rectal cancer is the cornerstone therapy, an ultralow anterior resection with or without intersphincteric resection (ISR) has become an alternative standard surgical method for selected patients. Many studies have reported on the oncological safety of the ISR, but few of them have addressed the issue the functional outcome. Furthermore, an abdominoperineal resection (APR) has problems with high rates of tumor perforations and positive circumferential resection margins, and those factors have contributed to its having a high rate of local recurrence and a poor survival rate for rectal cancer compared with sphincter-saving procedures. Recently, great efforts have been made to reduce these problems, and the total levator excision or the extended APR concept has emerged. Surgical management for low rectal cancer should aim to radically excise the tumor and to preserve as much of the sphincter function as possible by using multidisciplinary approaches. However, further prospective clinical trials are needed for tailored treatment of rectal cancer patients.
Humans ; Lymphoid Tissue ; Rectal Neoplasms ; Recurrence ; Survival Rate

An axial-pattern flap can be transferred as the free-flap and has many merits over a random-pattern local flap. However, this has limitations of available vascular architecture and donor site. To overcome these problems, many types of prefabricated flaps have been designed using vascular bundles. It is possible to convert a random-pattern flap to a neovascularized axial-pattern flap by transferring a vascular pedicle. In an attempt to study the effects of prefabrication using vascular bundles, the survival rate between random-pattern flap and prefabricated axial-pattern flap was compared in this study. The rabbits were divided into two groups. The control group was consisted of the random-pattern flap and the prefabricated group was consisted of the prefabricated axial-pattern flap using femoral vascular pericles of rabbits. Femoral vascular pedicles were transferred under the 5x5cm lower abdominal flaps without any perivascular tissue. Three weeks later, random-pattern flaps were elevated without any axial vascular pedicle and prefabricated flaps were elevated based on the transferred femoral vascular pericles. The survival rate of the flaps in the control group and experimental group was 67.37% and 98.87% respectively. Based on the result of t-test there was significant difference between two groups. According to these results, it is concluded that prefabricated flap using transferred vascular pedicle was more effective than random-pattern flap. We think that this technique is versatile for wound repair and for use in other aspects of plastic and reconstructive surgery.
Humans ; Plastics ; Rabbits* ; Survival Rate ; Tissue Donors ; Wounds and Injuries

OBJECTIVEClinical application of autologous fat grafting (AFG) is quickly expanding. Despite the widely acceptance, long-term survival rate (SR) of AFG remains a question not yet solved. Meanwhile, although rare, severe complications related to AFG including vision loss, stroke even death could be seen in the literature.

DATA SOURCESA comprehensive research of PubMed database to June 2013 was performed according to guidelines of the American Society of Plastic Surgeons Fat Graft Task Force Assessment Methodology. Articles were screened using predetermined inclusion and exclusion criteria.

STUDY SELECTIONData collected included patient characteristics, surgical technique, donor site, recipient site, graft amount, and quantified measurement methods. Patient cohorts were pooled, and SR was calculated. All the severe complications were also summarized according to the different clinical characteristics.

RESULTSOf 550 articles, 16 clinical articles and 10 animal studies met the inclusion criteria and provided quantified measurement methods. Totally, 596 patients were included. SR varied from 34% to 82% in breast and 30-83% in the facial area. Nude mice were applied to investigate human fat grafting SR (38.3-52.5% after 15 weeks). Rabbits were commonly used to study animal AFG SR (14.00-14.56% after 1-year). Totally, 21 severe complications were reported, including death (2), stroke (10), vision loss (11, 8 of which accompanied with stroke), sepsis (3), multiple abscess (1) and giant fat necrotic cyst (2). Ten of these complications happened within 10 years.

CONCLUSIONSThere is no unified measurement method to evaluate fat graft SR until now and no clinical evidence to show better SR according to different donor and recipient cite. Body mass index change between pre- and postoperation may be the bias factor in evaluating fat SR. Fat embolisms of the ophthalmic artery and the middle cerebral artery are the most severe complication of AFG and still lack of effective treatment.

No abstract available.
Graft Survival ; Humans ; Renal Artery ; Tissue Donors ; Transplants

PURPOSE: The pretransplant pregnancy has been thought to be a detrimental factor for graft survival following renal allografts. However, graft survival in woman who underwent renal allografts from her offspring donor can be affected either positively by chimerism during fetal circulation or negatively by hypersensitive response. We attempted to define the role of pretransplant pregnancy on allografts survival of mother recipients from offspring donors. METHODS: During July 1, 1990 through July 31, 2002 117 patients were enrolled in this study. We divided these patients into 3 groups: group 1 (mothers receiving allografts from offspring) of 40 patients, group 2 (fathers receiving allografts from offspring) of 42 patients, and group 3 (women with a history of pregnancy and received allografts from unrelated donors) of 35 patients. We analysed the rejection rate, and patient and graft survival among the 3 groups. RESULTS: The acute rejection episodes (ARE) within 3 months were prevalent in the patients who received allografts from offspring. But after 3 months, no significant difference was observed among the three groups. The 1, 5 years graft survival rate of each group was 90.0%, 85.5% in group 1, 97.4%, 97.4% in group 2 and 94.3%, 94.3% in group 3. And the 1, 5 years patient survival rate was 92.5%, 88.1% in group 1, 100%, 100% in group 2 and 94.3%, 94.3% in group 3. CONCLUSION: From these results we can assume that the higher rejection rate and somewhat lower graft survival rate in mother recipients who underwent renal allografts from the offspring donors were caused by the anamnestic response from presensitization during pregnancy. To achieve better results in this group, a perioperative cautious care with different strategy of immunosuppressant is recommended.
Allografts* ; Chimerism ; Female ; Graft Survival ; Humans ; Mothers ; Pregnancy* ; Survival Rate ; Tissue Donors*

Preservation of tissue viability is very important for successful fetal mesencephalic transplantation. Cryopreservation methods have been regarded as a kind of useful technique to maintain tissue viability during the preservation period. Tissue viability and neurite formation rate of cryopreserved tissue would be influenced by many factors. Authors have been looking for the most ideal condition for maintaining tissue viability of cryopreserved tissue after thawing. For the first step to define the most ideal condition of crypreservation, the present study investigated whether tissue viability and neurite formation rate could be influenced by length of cryopreservation time. We used the ventral mesencephalon from 14 day old rat embryos. Tissue blocks of ventral mesencephalon were cooled in a controlled rate freezer from room temperature to -80degreesC at a rate of 5degreesC per minute. Then tissue blocks were transfered into the liquid nitrogen tanks. We divided the tissue blocks into 4 groups(fresh, 1 week, 3 weeks, 5 weeks) by the duration of cryopreservation period. We compared the cell viability and neurite formation rate of each group after thawing. We estimated the cell viability and the neurite formation of the fresh group. The fresh group showed 92% cell viability and the other three cryopreserved groups showed 65% cell viability. Cell viability of cryopreserved group was reduced significantly after thawing, comparing with the fresh groups. But differences of neurite formation rate of each group was not significant. Our result indicates that cryopreservation time could not affect the cell viability and neurite formation rate. Therefore, if we improve the reduction rate of cell viability after thawing, we would be able to obtain the better result of fetal mesencephalic transplantation.
Animals ; Cell Survival* ; Cryopreservation ; Embryonic Structures ; Mesencephalon ; Neurites* ; Neurons* ; Nitrogen ; Rats ; Tissue Survival

In making prefabricated flaps, a bed isolation has been suggested by many previous studies as an adjunctive procedure to incite revascularization of the flap from vascular carrier by inducing a ischemic state as like as a delay procedure and blocking the neovascularization from the bed. To decide whether the bed should be isolated, or not during the flap prefabrication, we need to know it actually affects the survival of prefabricated skin flap. If it does, we should also know how and how far. The purpose of this study was to demonstrate the effects of bed isolation and to investigate whether the bed isolation is necessary during flap prefabrication. Prefabrication of an 3x4 cm sized abdominal donor site was performed as like pocket in both sides, using the transposition of both saphenous pedicles with gracilis fascia to the subpanniculus layer in 30 Sprague-Dawley rats. All flaps in the left side were isolated with silicone sheet from the bed of rectus fascia(experimental side) and all in the right were not(control side). Above sized flaps were elevated as an island and reposed immediately two weeks after prefabrication in group I(n=10), three weeks after in group II(n=10), and four weeks after in group III(n=10). Flap survival was assessed at day 3 after the flap elevation and reposition. The mean proportion of the survival area was 79.3% in the left and 88.7% in the right side in group 1. In the group II,68.7% in the left and 69.9% in the right, and 64.1% in the left side and 79.3% in the right in group III. Grossly, this results showed that the survival area of th prefabricated flap with bed isolation was less than that of non-isolated flap, which was different from the results of previous similar studies. But in comparing to the survival area of the prefabricated flaps for each time interval, there was no significant statistical difference between the control side and the experimental side(p>0.05). And the time interval between the flap prefabrication and the elevation did not affect the survival rate in the same side for each prefabricated method(p>0.05). With further study of histologic examination, the inflammatory reaction and the development of the granulation tissue were more plentiful in the experimental sides due to the foreign body reaction by silicone sheet insertion, and numerous small sized vessels were present around the implanted pedicles. In conclusion, during flap prefabrication, isolation of the bed with a silicone sheet did not improve the survival of prefabricated skin flaps. And may be cause of the increased survival area in the isolated groups was thought to be secondary effects of the inflammatory reaction rather than neovascularization induced by ischemic state.
Fascia ; Foreign-Body Reaction ; Granulation Tissue ; Humans ; Rats, Sprague-Dawley ; Silicones* ; Skin ; Survival Rate ; Tissue Donors