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1.
Biomater Res ; 27(1): 70, 2023 Jul 16.
Article in English | MEDLINE | ID: mdl-37455318

ABSTRACT

BACKGROUND: Adipose tissue-derived microvascular fragments are functional vessel segments derived from arterioles, capillaries, and veins. Microvascular fragments can be used as vascularization units in regenerative medicine and tissue engineering containing microvascular networks. However, the in vivo therapeutic and vascularization properties of human microvascular fragments have not been investigated. METHODS: In this study, we isolated microvascular fragments, stromal vascular fractions, and mesenchymal stem cells from human lipoaspirate and studied their therapeutic efficacy and in vivo vasculogenic activity in a murine model of hindlimb ischemia. In addition, in vivo angiogenic activity and engraftment of microvascular fragments into blood vessels were measured using Matrigel plug assay. RESULTS: Both microvascular fragments and stromal vascular fractions contain not only mesenchymal stem cells but also endothelial progenitor cells. In a Matrigel plug assay, microvascular fragments increased the number of blood vessels containing red blood cells more than mesenchymal stem cells and stromal vascular fractions did. The engraftment of the microvascular fragments transplanted in blood vessels within the Matrigel plug significantly increased compared to the engraftment of mesenchymal stem cells and stromal vascular fractions. Moreover, intramuscular injection of microvascular fragments markedly increased blood flow in the ischemic hindlimbs and alleviated tissue necrosis compared to that of mesenchymal stem cells or stromal vascular fractions. Furthermore, transplanted microvascular fragments formed new blood vessels in ischemic limbs. CONCLUSIONS: These results suggest that microvascular fragments show improved engraftment efficiency and vasculogenic activity in vivo and are highly useful for treating ischemic diseases and in tissue engineering. Adipose tissue-derived microvascular fragments are vascularization units in regenerative medicine and tissue engineering containing microvascular networks. Intramuscular injection of microvascular fragments markedly increased blood flow in the ischemic hindlimbs and alleviated tissue necrosis. The present study suggests that microvascular fragments show improved engraftment efficiency and vasculogenic activity in vivo and are highly useful for treating ischemic diseases and in tissue engineering.

2.
Bioprocess Biosyst Eng ; 42(4): 603-610, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30617415

ABSTRACT

Polyhydroxybutyrates (PHB) are biodegradable polymers that are produced by various microbes, including Ralstonia, Pseudomonas, and Bacillus species. In this study, a Vibrio proteolyticus strain, which produces a high level of polyhydroxyalkanoate (PHA), was isolated from the Korean marine environment. To determine optimal growth and production conditions, environments with different salinity, carbon sources, and nitrogen sources were evaluated. We found that the use of a medium containing 2% (w/v) fructose, 0.3% (w/v) yeast extract, and 5% (w/v) sodium chloride (NaCl) in M9 minimal medium resulted in high PHA content (54.7%) and biomass (4.94 g/L) over 48 h. Addition of propionate resulted in the production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (P(HB-co-HV)) copolymer as propionate acts as a precursor for the HV unit. In these conditions, the bacteria produced poly(3-hydroxybutyrate-co-3-hydroxyvalerate) containing a 15.8% 3HV fraction with 0.3% propionate added as the substrate. To examine the possibility of using unsterilized media with high NaCl content for PHB production, V. proteolyticus was cultured in sterilized and unsterilized conditions. Our results indicated a higher growth, leading to a dominant population in unsterilized conditions and higher PHB production. This study showed the conditions for halophilic PHA producers to be later implemented at a larger scale.


Subject(s)
Aquatic Organisms , Polyhydroxyalkanoates/biosynthesis , Seawater/microbiology , Vibrio , Water Microbiology , Aquatic Organisms/growth & development , Aquatic Organisms/isolation & purification , Korea , Vibrio/genetics , Vibrio/isolation & purification
3.
Int J Biol Macromol ; 123: 117-123, 2019 Feb 15.
Article in English | MEDLINE | ID: mdl-30428310

ABSTRACT

Naturally produced polyhydroxyalkanoates (PHAs) biopolymers have limited medical applications due to their brittle and hydrophobic nature. In this study poly(3-hydroxybutyrate-co-3-hydroxyvalerate) P(3HB-co-3HV) copolymer was produced using engineered Escherichia coli YJ101, and further functionalized with ascorbic acid using Candida antarctica lipase B mediated esterification. Copolymer P(3HB-co-3HV)-ascorbic acid showed lower degree of crystallinity (9.96%), higher thermal degradation temperature (294.97 °C) and hydrophilicity (68°) as compared to P(3HB-co-3HV). Further, P(3HB-co-3HV)-ascorbic acid biomaterial showed 14% scavenging effect on 1,1-diphenyl-2-picryl-hydrazyl (DPPH), and 1.6 fold increase in biodegradability as compared to P(3HB-co-3HV). Improvement of PHAs polymer properties by adding functional groups could be a good approach to increase their biodegradability, economic value and important applications in the medical field.


Subject(s)
Antioxidants/metabolism , Ascorbic Acid/metabolism , Biocompatible Materials/metabolism , Fungal Proteins/metabolism , Lipase/metabolism , Polyesters/metabolism , Biodegradation, Environmental , Biphenyl Compounds/metabolism , Escherichia coli/metabolism , Picrates/metabolism , Polyhydroxyalkanoates/metabolism , Polymers/metabolism
4.
Plast Reconstr Surg ; 143(1): 88e-98e, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30325895

ABSTRACT

BACKGROUND: Improving flap survival is essential for successful soft-tissue reconstruction. Although many methods to increase the survival of the distal flap portion have been attempted, there has been no widely adopted procedure. The authors evaluated the effect of flap preconditioning with two different modes (continuous and cyclic) of external volume expansion (pressure-controlled cupping) in a rat dorsal flap model. METHODS: Thirty rats were randomly assigned to the control group and two experimental groups (n = 10 per group). The continuous group underwent 30 minutes of preconditioning with -25 mmHg pressure once daily for 5 days. The cyclic group received 0 to -25 mmHg pressure for 30 minutes with the cyclic mode once daily for 5 days. On the day after the final preconditioning, caudally based 2 × 8-cm dorsal random-pattern flaps were raised and replaced in the native position. On postoperative day 9, the surviving flap area was evaluated. RESULTS: The cyclic group showed the highest flap survival rate (76.02 percent), followed by the continuous and control groups (64.96 percent and 51.53 percent, respectively). All intergroup differences were statistically significant. Tissue perfusion of the entire flap showed similar results (cyclic, 87.13 percent; continuous, 66.64 percent; control, 49.32 percent). Histologic analysis showed the most increased and organized collagen production with hypertrophy of the attached muscle and vascular density in the cyclic group, followed by the continuous and control groups. CONCLUSION: Flap preconditioning with the cyclic mode of external volume expansion is more effective than the continuous mode in an experimental rat model.


Subject(s)
Graft Rejection/prevention & control , Ischemic Preconditioning/methods , Pressure , Surgical Flaps/blood supply , Surgical Flaps/transplantation , Animals , Disease Models, Animal , Graft Survival , Male , Random Allocation , Rats , Rats, Sprague-Dawley , Regional Blood Flow/physiology , Reperfusion Injury/prevention & control , Risk Assessment , Sensitivity and Specificity , Stress, Mechanical
5.
Bioprocess Biosyst Eng ; 41(8): 1195-1204, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29737409

ABSTRACT

n-Butanol is considered as the next-generation biofuel, because its physiochemical properties are very similar to fossil fuels and it could be produced by Clostridia under anaerobic culture. Due to the difficulties of strict anaerobic culture, a host which can be used with facultative environment was being searched for n-butanol production. As an alternative, Shewanella oneidensis MR-1, which is known as facultative bacteria, was selected as a host and studied. A plasmid containing adhE2 encoding alcohol dehydrogenase, various CoA transferases (ctfAB, atoAD, pct, and ACT), and acs encoding acetyl-CoA synthetase were introduced and examined to S. oneidensis MR-1 to produce n-butanol. As a result, ctfAB, acs, and adhE2 overexpression in S. oneidensis-pJM102 showed the highest n-butanol production in the presence of 2% of N-acetylglucosamine (NAG), 0.3% of butyrate, and 0.1 mM of IPTG for 96 h under microaerobic condition. When more NAG and butyrate were fed, n-butanol production was enhanced, producing up to 160 mg/L of n-butanol. When metal ions or extra electrons were added to S. oneidensis-pJM102 for n-butanol production, metal ion as electron acceptor or supply of extra electron showed no significant effect on n-butanol production. Overall, we made a newly engineered S. oneidensis that could utilize NAG and butyrate to produce n-butanol. It could be used in further microaerobic condition and electricity supply studies.


Subject(s)
1-Butanol/metabolism , Bacterial Proteins , Butyrates/metabolism , Microorganisms, Genetically-Modified , Plasmids , Shewanella , Bacterial Proteins/biosynthesis , Bacterial Proteins/genetics , Clostridium/genetics , Microorganisms, Genetically-Modified/growth & development , Microorganisms, Genetically-Modified/metabolism , Plasmids/genetics , Plasmids/metabolism , Shewanella/genetics , Shewanella/growth & development
6.
Biotechnol Bioeng ; 115(8): 1971-1978, 2018 08.
Article in English | MEDLINE | ID: mdl-29663332

ABSTRACT

Acetic acid is an abundant material that can be used as a carbon source by microorganisms. Despite its abundance, its toxicity and low energy content make it hard to utilize as a sole carbon source for biochemical production. To increase acetate utilization and isobutanol production with engineered Escherichia coli, the feasibility of utilizing acetate and metabolic engineering was investigated. The expression of acs, pckA, and maeB increased isobutanol production by up to 26%, and the addition of TCA cycle intermediates indicated that the intermediates can enhance isobutanol production. For isobutanol production from acetate, acetate uptake rates and the NADPH pool were not limiting factors compared to glucose as a carbon source. This work represents the first approach to produce isobutanol from acetate with pyruvate flux optimization to extend the applicability of acetate. This technique suggests a strategy for biochemical production utilizing acetate as the sole carbon source.


Subject(s)
Acetate-CoA Ligase/biosynthesis , Acetate-CoA Ligase/metabolism , Acetates/metabolism , Butanols/metabolism , Escherichia coli/metabolism , Gene Expression , Metabolic Engineering/methods , Acetate-CoA Ligase/genetics , Escherichia coli/genetics
7.
Bioprocess Biosyst Eng ; 41(2): 229-235, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29124334

ABSTRACT

Polyhydroxyalkonate (PHA) is a type of polymer that has the potential to replace petro-based plastics. To make PHA production more economically feasible, there is a need to find a new carbon source and engineer microbes to produce a commercially valuable polymer. Coffee waste is an inexpensive raw material that contains fatty acids. It can act as a sustainable carbon source and seems quite promising with PHA production in Ralstonia eutropha, which is a well-known microbe for PHA accumulation, and has the potential to utilize fatty acids. In this study, to make poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (P(HB-co-HHx)), which has superior properties in terms of biodegradability, biocompatibility, and mechanical strength, engineered strain Ralstonia eutropha Re2133 overexpressing (R)-specific enoyl coenzyme-A hydratase (phaJ) and PHA synthetase (phaC2) with deletion of acetoacetyl Co-A reductases (phaB1, phaB2, and phaB3) was used to produce PHA from coffee waste oil. At a coffee oil concentration of 1.5%, and C/N ratio of 20, the R. eutropha Re2133 fermentation process results in 69% w/w of DCW PHA accumulation and consists of HB (78 mol%) and HHx (22 mol%). This shows the feasibility of using coffee waste oil for P(HB-co-HHx) production, as it is a low-cost fatty acid enriched waste material.


Subject(s)
3-Hydroxybutyric Acid/biosynthesis , Bacterial Proteins , Coffee/chemistry , Cupriavidus necator , Metabolic Engineering , Plant Oils/chemistry , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Caproates , Cupriavidus necator/genetics , Cupriavidus necator/metabolism
8.
Arch Plast Surg ; 43(4): 352-9, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27462568

ABSTRACT

BACKGROUND: The objective of this study was to develop a new surgical technique by combining traditional abdominoplasty with liposuction. This combination of operations permits simpler and more accurate management of various abdominal deformities. In lipoabdominoplasty, the combination of techniques is of paramount concern. Herein, we introduce a new combination of liposuction and abdominoplasty using deep-plane flap sliding to maximize the benefits of both techniques. METHODS: Deep-plane lipoabdominoplasty was performed in 143 patients between January 2007 and May 2014. We applied extensive liposuction on the entire abdomen followed by a sliding flap through the deep plane after repairing the diastasis recti. The abdominal wound closure was completed with repair of Scarpa's fascia. RESULTS: The average amount of liposuction aspirate was 1,400 mL (700-3,100 mL), and the size of the average excised skin ellipse was 21.78×12.81 cm (from 15×10 to 25×15 cm). There were no major complications such as deep-vein thrombosis or pulmonary embolism. We encountered 22 cases of minor complications: one wound infection, one case of skin necrosis, two cases of undercorrection, nine hypertrophic scars, and nine seromas. These complications were solved by conservative management or simple revision. CONCLUSIONS: The use of deep-plane lipoabdominoplasty can correct abdominal deformities more effectively and with fewer complications than traditional abdominoplasty.

9.
Aesthetic Plast Surg ; 36(3): 497-503, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22311003

ABSTRACT

UNLABELLED: Due to recent trends in liposuction, anatomic consideration of the body's fatty layers is essential. Based on this knowledge, a circumferential approach to achieving maximal aesthetic results is highlighted. In the upper arm, aspiration of fat from only the posterolateral region can result in skin flaccidity and disharmony of the overall balance of the upper arm contour. Different suction techniques were applied depending on the degree of fat accumulation. If necessary, the operation area was extended around the axillary and scapular regions to overcome the limitations of the traditional method and to achieve optimal effects. To maximize skin contracture and redraping, the authors developed three-dimensional circumferential liposuction (3D-CL) based on two concepts: circumferential aspiration of the upper arm, to which was applied different fluid infiltration and liposuction techniques in three anatomic compartments (anteromedial, anterolateral, and posterolateral), and extension of liposuction to the periaxillar and parascarpular areas. A total of 57 female patients underwent liposuction of their excess arm fat using this technique. The authors achieved their aesthetic goals of a straightened inferior brachial border and a more slender body contour. Complications occurred for five patients including irregularity, incision-site scar, and transient pigmentation. Through 3D-CL, the limitations of traditional upper arm liposuction were overcome, and a slender arm contour with a straightened inferior brachial border was produced. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors at http://www.springer.com/00266.


Subject(s)
Arm/surgery , Lipectomy/methods , Obesity/surgery , Overweight/surgery , Adolescent , Adult , Female , Humans , Middle Aged , Young Adult
10.
Aesthetic Plast Surg ; 30(3): 327-32, 2006.
Article in English | MEDLINE | ID: mdl-16733777

ABSTRACT

Recent advances in liposuction techniques now make it possible to remove considerable amounts of subcutaneous adipose tissue. However, the metabolic consequences of this procedure are not well documented. The aim of this study was to identify the effects from the surgical removal of subcutaneous fat on the body weights and serum lipids of patients who have undergone large-volume liposuction. In this study, eleven consecutive patients with a minimum aspirate volume of 5,000 ml were evaluated, and their serum lipids were measured at a postoperative 2-month follow-up assessment. Tumescent fluid was infiltrated using the superwet technique. The liposuction device used was a Liposlim power-assisted liposuction system. The amount of solution infiltrated and the volume of aspirate were measured. Pre- and postoperative serum lipids, body weights, and body mass indices were compared. Statistical analysis was performed on lipid profile changes and aspirate volumes using Spearman's correlations. The average volumes of infiltrate and aspirate were 7,241 and 6,790 ml, respectively. Mean body weight decreased from 64.5 +/- 18.8 to 59.9 s +/- 17.8 kg (p < 0.01). The change in body weight per 1 l of aspirate volume was 0.67 +/- 0.10 kg/l. The mean body mass index dropped from 23.8 +/- 4.4 to 22.0 +/- 4.2 kg/m(2) (p < 0.01), and the mean total serum cholesterol levels from 168.2 +/- 23.6 to 162.9 +/- 26.5 mg/dl, an average of 3.2%. The mean low-density lipoprotein (LDL) decreased from 94.3 +/- 20.5 to 89.5 +/- 19.0 mg/dl, a 5.1% drop, and the mean high-density lipoprotein (HDL) decreased from 55.8 +/- 9.5 to 53.7 +/- 10.7 mg/dl, a 3,8% drop. The mean HDL/LDL proportion increased from 62.6 +/- 20.9% to 63.5 +/- 22.4%, averaging 1.4%. However, no significant correlation was found between the aspirated volume of fat and lipid profile change. In conclusion, over a 2-month period, large-volume liposuction reduced weight and total cholesterol level and increased the HDL/LDL ratio. The authors hope to discover whether the therapeutic impact of liposuction is long-lasting, and to determine whether it reduces the morbidity and mortality associated with obesity.


Subject(s)
Asian People , Lipectomy/methods , Lipids/blood , Abdominal Muscles/surgery , Adult , Cholesterol/blood , Female , Humans , Korea , Lipoproteins, HDL/blood , Lipoproteins, LDL/blood , Male , Pilot Projects , Weight Loss
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