OBJECTIVETo investigate the relationship between the survival rate of expanded flap and expansion volume.

METHODSThe minipigs were used and divided into 5 groups according to different expansion volume of the tissue expanders: injection to full content, 50% over content, 100% over content, 0% content and normal control. In each animal, 4 expanders (100 ml) were designed to be implanted at the bilateral side of back. Normal skin control was also designed at the back. The skin histologic change and flap survival rate were detected and analyzed when the expansion volume changed.

RESULTSThe flap survival rate increased along with the increase of expansion volume. While the survival rate decreased when the expansion volume was exceeded to 100% over content.

CONCLUSIONSIn soft tissue and skin expansion, the flap survival rate and the flap size increased as the expansion is over the standard volume, while over-expansion to 100% over content may cause decreased survival rate of expanded flap.

Animals ; Back ; Graft Survival ; Surgical Flaps ; physiology ; Swine ; Swine, Miniature ; Tissue Expansion ; Tissue Expansion Devices

The research was conducted to study the breeding system of Prunella vulgaris L. Flowering dynamics was observed. Pollen viability, stigma receptivity, pollen-ovule ratio (P/O), out-crossing index (OCI) were measured. Bagging experiments were conducted. The results showed that the life span of one single flower was 1-2 days, the flowering span for the inflorescence of stalk was 7-14 days, the P/O was 1 046+/-148. 26, the OCI was 2. Combined with results of bagging experiment, the breeding system of P. vulgaris L. was mixed with cross-polination and self pollination. In the absence of pollination insects, the pollination and fertilization can be accomplished with high seed setting rate, and the seeds have a relatively high germination rate.
Breeding ; Pollen ; growth & development ; physiology ; Pollination ; Prunella ; growth & development ; physiology ; Tissue Survival

Fibroblast viability of a natural tissue valve for replacing a defective heart valve through allograft or xenograft has been suggested to affect its clinical durability. In this study, the cell viability and enzymatic activity of porcine heart valve leaflets were examined in regard to concerning to the preservation process [variable warm ischemic time (WIT), cold ischemic time (CIT), and cryopreservation]. Porcine heart enblocs were obtained and valve dissection was performed after 2, 12, 24, or 36 hours, in respective groups A, B, C, and D, as WIT. Each group was stored for 24 hours as CIT and cryopreserved. Leaflets were dissected from a valved conduit after each process, and cell viability and enzymatic activity in the leaflet were investigated using trypan blue staining and API ZYM kits. WIT extension significantly decreased fibroblast viability (p < 0.05, 92.25 +/- 2.7% at 2 hours, 84.9 +/- 6.7% at 12 hours, 57.0 +/- 10.2% at 24 hours, 55.9 +/- 7.9% at 36 hours), while CIT for 24 hours was also influenced significantly (p < 0.05), whereas cryopreservation demonstrated no effect on cellular viability. In enzyme activity observation, several enzymes related to lipid or nucleotide degradation (esterase, esterase lipase, particularly phosphatase, phosphohydrolase) were remarkably changed following the valve-fabrication process. After 24 hours CIT, these enzymatic activities in groups B, C and D significantly increased, but the activities decreased after cryopreservation. Particularly, both the viability and enzymatic activity showed remarkable changes after CIT in group B (WIT = 12 hours). These results suggest that WIT is more important than CIT in maintaining viability of the valve, and that completing all the cryopreservation process within 12 hours after acquisition is recommended.
Animal ; Cryopreservation* ; Heart Valves/physiology* ; Heart Valves/enzymology* ; Swine ; Tissue Survival/physiology*

Bone marrow harvested by aspiration contains connective tissue progenitor cells which can be selectively isolated and induced to express bone phenotype in vitro. The osteoblastic progenitor can be estimated by counting the number of cells attach using the haemacytometer. This study was undertaken to test the hypothesis that human aging is associated with a significant change on the number of osteoblastic progenitors in the bone marrow. Bone marrow aspirates were harvested from 38 patients, 14 men (age 11-70) and 24 women (age 10-70) and cultured in F12: DMEM (1:1). In total 15 bone marrow samples have been isolated from patients above 40 years old (men/women) of age. Fourteen (93.3%) of this samples failed to proliferate. Only one (6.7%) bone marrow sample from a male patient, aged 59 years old was successfully cultured. Seventy percent (16/23) of the samples from patient below than 40 years old were successfully cultured. However, our observation on the survival rate for cells of different gender from patient below 40 years old does not indicate any significant difference. From this study, we conclude that the growth of bone marrow stromal cells possibly for bone engineering is better from bone marrow aspirates of younger patient.
Age Factors ; Bone Marrow Cells/*cytology ; Cell Aging/*physiology ; Cell Division/*physiology ; Cell Survival/physiology ; Mesenchymal Stem Cells/*cytology ; Osteoblasts/*cytology ; Sex Factors ; Stromal Cells/cytology ; *Tissue Engineering

OBJECTIVEthe main purpose of this study is to develop an assay for detection of skin viability in situ.

METHODSTwo nucleic acid dyes, SYTO 13 and ethidium bromide (EB), are used to assess the viability of skin tissue. The viability of cells can be determined by different colors under fluorescence microscope. In this study, the recovery of skin restored at 4 degrees C for different periods is measured by SYTO/EB dyes and a type of indirect assessment, WST-1. Then both results are compared.

RESULTSThe results measured by two methods showed that the viability of skin tissue was nearly 30% after two weeks storage. At any point of experiment, the data from two methods have not obvious variance.

CONCLUSIONThe assessment of skin viability by SYTO/EB is also quick, sensitive and convenient. At the same time the viability of any type of cells can be observed in situ. So it can be considered as an available method for detection of skin viability.

Animals ; Cell Survival ; physiology ; Cryopreservation ; Ethidium ; Male ; Models, Animal ; Rats ; Skin ; cytology ; metabolism ; Skin Physiological Phenomena ; Tissue Preservation ; methods

OBJECTIVE: The aim of this study was to investigate the relationship between the diffusion and perfusion parameters in hyperacute infarction, and we wanted to determine the viability threshold for the ischemic penumbra using diffusion- and perfusion-weighted imaging (DWI and PWI, respectively). MATERIALS AND METHODS: Both DWI and PWI were performed within six hours from the onset of symptoms for 12 patients who had suffered from acute stroke. Three regions of interest (ROIs) were identified: ROI 1 was the initial lesion on DWI; ROI 2 was the DWI/PWI mismatch area (the penumbra) that progressed onward to the infarct; and ROI 3 was the mismatch area that recovered to normal on the follow-up scans. The ratios of apparent diffusion coefficient (ADC), the relative cerebral blood volume (rCBV), and the time to peak (TTP) were calculated as the lesions' ROIs divided by the contralateral mirror ROIs, and these values were then correlated with each other. The viability threshold was determined by using the receiver operating characteristic (ROC) curves. RESULTS: For all three ROIs, the ADC ratios had significant linear correlation with the TTP ratios (p < 0.001), but not with the rCBV ratios (p = 0.280). There was no significant difference for the ADC and rCBV ratios within the ROIs. The mean TTP ratio/TTP delay between the penumbras' two ROIs showed a significant statistical difference (p < 0.001). The cutoff value between ROI 2 and ROI 3, as the viability threshold, was a TTP ratio of 1.29 (with a sensitivity and specificity of 86% and 73%, respectively) and a TTP delay of 7.8 sec (with a sensitivity and specificity of 84% and 72%, respectively). CONCLUSION: Determining the viability thresholds for the TTP ratio/delay on the PWI may be helpful for selecting those patients who would benefit from the various therapeutic interventions that can be used during the acute phase of ischemic stroke.
Acute Disease ; Aged ; Cerebrovascular Accident/*diagnosis ; Female ; Humans ; Magnetic Resonance Imaging/*methods ; Male ; Middle Aged ; Sensitivity and Specificity ; Tissue Survival/*physiology

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 change of endothelial cell viability due to corticosteroid treatment in stored rabbit corneas was investigated. Hydrocortisone was injected into the anterior chamber of enucleated eyeballs which were stored in a moist chamber. After 24,48, or 72 hours of storage, the cornea was removed and stained with trypan blue. The unstained endothelial cells were counted under the light microscope in order to determine the density of viable endothelial cells. The same procedures were done on the contralateral eye with normal saline injected into the anterior chamber instead of hydrocortisone as a control. The density of viable endothelial cells in the corticosteroid-treated group was higher than that of the control group by 1.75%,14.39%, and 27.40% in 24,45, and 72 hour-stored corneas, respectively.
Animals ; Cell Survival/drug effects ; Endothelium, Corneal/*drug effects ; Female ; Hydrocortisone/*pharmacology/physiology ; Male ; Rabbits ; Time Factors ; Tissue Preservation/*methods

Animals ; Animals, Newborn ; Cell Separation ; methods ; Cell Survival ; Cryopreservation ; Hepatocytes ; cytology ; physiology ; Rats ; Rats, Wistar ; Tissue Preservation

BACKGROUND: Delayed graft function (DGF) is the main cause of renal function failure after kidney transplantation. This study aims at investigating the value of hypothermic machine perfusion (HMP) parameters combined with perfusate biomarkers on predicting DGF and the time of renal function recovery after deceased donor (DD) kidney transplantation. METHODS: HMP parameters, perfusate biomarkers and baseline characteristics of 113 DD kidney transplantations from January 1, 2019 to August 31, 2019 in the First Affiliated Hospital of Xi'an Jiaotong University were retrospectively analyzed using univariate and multivariate logistic regression analysis. RESULTS: In this study, the DGF incidence was 17.7% (20/113); The multivariate logistic regression results showed that terminal resistance (OR: 1.879, 95% CI 1.145-3.56) and glutathione S-transferase (GST)(OR = 1.62, 95% CI 1.23-2.46) were risk factors for DGF; The Cox model analysis indicated that terminal resistance was an independent hazard factor for renal function recovery time (HR = 0.823, 95% CI 0.735-0.981). The model combining terminal resistance and GST (AUC = 0.888, 95% CI: 0.842-0.933) significantly improved the DGF predictability compared with the use of terminal resistance (AUC = 0.756, 95% CI 0.693-0.818) or GST alone (AUC = 0.729, 95% CI 0.591-0.806). CONCLUSION According to the factors analyzed in this study, the combination of HMP parameters and perfusate biomarkers displays a potent DGF predictive value.
Biomarkers ; Delayed Graft Function ; Graft Survival ; Humans ; Kidney/physiology* ; Kidney Transplantation/adverse effects* ; Organ Preservation ; Perfusion ; Retrospective Studies ; Tissue Donors