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At least 1,405 records · Page 78Linked to original sources
PubMed2004

Human VEGF165-myoblasts produce concomitant angiogenesis/myogenesis in the regenerative heart.

Bioengineering the regenerative heart may provide a novel treatment for heart failure. On May 14, 2002, a 55-year-old man suffering from ischemic myocardial infarction received 25 injections carrying 465 million cGMP-produced pure myoblasts into his myocardium after coronary artery bypass grafting. As on August 28, 2002, his EKG was normal and showed no arrhythmia. His ejection fraction increased by 13%. He no longer experienced shortness of breath and angina as he did before the treatment. Three myogenesis mechanisms were elucidated with 17 human/porcine xenografts using cyclosporine as immunosuppressant. Some myoblasts developed to become cardiomyocytes. Others transferred their nuclei into host cardiomyocytes through natural cell fusion. As yet others formed skeletal myofibers with satellite cells. De novo production of contractile filaments augmented the heart contractility. Human myoblasts transduced with VEGF165 gene produced six times more capillaries in porcine myocardium than in placebo. Xenograft rejection was not observed for up to 20 weeks despite cyclosporine discontinuation at 6 weeks. Pros and cons of autografts vs. allografts are compared to guide future development of heart cell therapy.

Animals↗
PubMed2004

Ocular surface stem cells and disease: current concepts and clinical applications.

Corneal and conjunctival epithelial stem cells are responsible for the homeostasis and regeneration of the ocular surface epithelium. Corneal epithelial stem cells reside in the basal region of the limbus, while the conjunctival forniceal region appears to be the site that is enriched in conjunctival stem cells. Ocular surface disease arising from limbal stem cell deficiency is characterised by persistent epithelial defects, corneal vascularisation, chronic inflammation, scarring and conjunctivalisation, resulting in visual loss. Limbal stem cell transplantation replaces the corneal stem cell population in these eyes with the hope of restoring vision. More recently, the use of bioengineered ocular surface tissue-equivalents has had promising results, and may represent the future for replacement and regeneration of ocular tissues in various ocular disorders.

Biomedical Engineering↗
PubMed2004

[Cloning and expression of the endo-beta-glucanase III cDNA gene from Trichoderma viride AS3.3711].

To study the construction of yeast bioengineering strain which can degrade cellulosic waste, an endo-beta-glucanase III (EG III) cDNA gene of Trichoderma viride AS3.3711 was isolated with RT-PCR protocol. After sequencing it was constructed on S. cerevisiae induceable expression vector pYES2. A L9 (3(4)) orthogonal design was used to optimize yeast sonication assistant transformation. The expression of EG III gene was induced by 2% beta-D-glactose, the transcription and expression of it was detected by Northern blotting and Congo Red method respectively. The endo-beta-glucanase activity was assayed as CMCase activity with CMC-Na as a substrate. The results show that the ORF of EG III was 1254 bp, encoding 418 aa, deducing molecular weight 44.1 x 10(3), group 5 (sonication treat time 60 s, incubate 40 min, SS-DNA 150 microg, heat shock 5 min) was the optimum one of the orthogonal experiment, and EG III transformants can produced clear hydrolysis halos on the Congo-Red-CMC plate. The measure of the enzyme activity show that the expression product can be expressed in active forms and secreted to the medium. The enzyme activity was approached the highest level (0.041 U/mL) when the culture time was 60 h. The optimized enzyme reaction temperature was 50 degrees C and the optimized pH was 5.8.

Cloning, Molecular↗
PubMed2004

Strain sensing fabric for hand posture and gesture monitoring.

Monitoring body kinematics and analyzing posture and gesture is an area of major importance in bioengineering and several other connected disciplines such as rehabilitation, sport medicine and ergonomics. Recent developments of new smart materials consent the realization of a new generation of garments with distributed sensors. What we present here is a sensing glove able to detect the posture and movements of the hand.

Biomechanical Phenomena↗
PubMedDate not supplied

Innovations in musculoskeletal oncologic surgery over the year 2000.

It is clear that recent advances in related fields including modern imaging, medical chemotherapy, and advances in materials and bioengineering has enhanced the opportunity for limb sparing surgery. This technique should be considered as a surgical option for these patients, when not at the expense of sound oncological procedure. Significant improvements have been noted over the later part of the 20th Century, and in recent years, advances in molecular oncology have resulted in an explosion of knowledge of the biology of cancer which will result in continued progress in this challenging area.

Adult↗
PubMedDate not supplied

[Advances and challenger in the diagnosis and medical treatment of respiratory diseases].

In the present article, we reviewed the most recent advances in the medical area and areas that contributed for the advances of medical science. We relate the advances in the areas of Biology and the Genetics, Bioengineering and Telecommunications among others. We also reviewed the most relevant advances in some areas of the more frequent pathologies of the respiratory tract, particularly those that urgently need new progress in terms of new techniques of diagnosis, therapeutics or prevention measures in the next years.

Humans↗
PubMed2005

[Influence of Mn2+ on the biotechmycin fermentation].

The effect of Mn2+ on the biotechmycin fermentation by Bioengineered strain WSJ-l-195 was studied. In the fermentation process, Mn2+ could improve the biological potency significantly, especially when Mn2+ concentration was 5 mmol/L added at 24 h. The pH profile of fermentation broth decreased gradually after 5 mmol/L Mn2+ supplemented at 24 h, and PMV was lower than that of the control sample. Further research about the influence of Mn2+ on the biosynthesis of biotechmycin was carried out in the aspect of organic acids. The results showed that concentrations of organic acids in a fermentation with 5 mmol/L Mn2+ supplemented at 24 h had been changed greatly, especially the concentration of propionic acid, of which the highest value was about 6 times as that in the control sample at 84 h. In addition, it was found that the yield of biotechmycin could be improved significantly with tiny amount of propionic acid added. Therefore, it can be concluded that Mn2+ has profound influence on the biosynthesis of biotechmycin: it enriches the biotechmycin precursor pool such as propionic acid and thus improves the yield of biotechmycin.

Culture Media↗
PubMed2005

University of Wyoming College of Engineering undergraduate design projects to aid Wyoming persons with disabilities, a mid-program review.

In Spring 2002 the University of Wyoming received National Science Foundation funding from the Division of Bioengineering and Environmental Systems to provide a meaningful design experience for University of Wyoming, College of Engineering students that will directly aid individuals with disabilities within the state of Wyoming. At the 2003 RMBS we presented a paper on the value of starting such a program. We have found that students receive a much richer capstone design experience when developing a project for direct use by a challenged individual. We are now approximately midway through this project. Since its inception the program has blossomed to include serving individuals in several regional states, outreach short courses to the community, projects have become of increasing difficulty and involve interdisciplinary teamwork, and many challenged individuals have been provided specialized one of a kind assistive devices. In this paper we will report on these advancements, lessons learned, and benefits received by participating in this vital program.

Biomedical Engineering↗
PubMed2005

Nanotechnology blooms, at last (Review).

Clinical trials for deadly pancreatic cancer have recently opened on two continents to evaluate the safety and efficacy of engineered nanoparticles guided by a targeted delivery system (TDS) to overcome the daunting barriers of turbulence, dilution, filtration, and inactivation encountered in the human circulatory system to deliver a killing designer gene to metastatic tumors that are refractory to conventional chemotherapy. The first patients receiving multiple intravenous infusions of the TDS-encapsulated genetic bullets have all responded favorably, prompting the FDA to grant orphan drug status for the nanobiotic medicine, Rexin-G, to assist in the development of this new cancer treatment. This review/commentary is an effort to translate the arcane terminology of physiology, biochemistry, and molecular genetics into the more generally accessible language of nanotechnology and medical delivery. While the text is somewhat erudite and laden at times with inconspicuous literary allusions, descriptions of the elegant bioengineering of nano-scale gene delivery vehicles are clear and the numerous references to classical mechanics of the Industrial Age are helpful.

Animals↗
PubMedDate not supplied

New treatments in inflammatory bowel disease.

Salicylates and steroids remain the mainstay of treatment for inflammatory bowel disease. New formulations which attempt to lower the rates of side effects are under evaluation. The value of azathioprine has been established in ulcerative colitis and cyclosporin has been shown to be of value. Dietary therapy in Crohn's disease has been the focus of a large amount of research and benefits have been demonstrated. New therapies including bioengineered drugs are anticipated.

Anti-Bacterial Agents↗
PubMed2005

Understanding the Social Implications of ICT in Medicine and Health: The Role of Professional Societies.

In past times, engineers and other ICT professionals could normally function exclusively within an environment of purely technical dimensions. This sphere could be easily delineated from those involving policy, political or social questions. Consequently, these professions could well be characterized as generally isolated from mainstream society, engendering a condition that Zussman (1985) has described as a "technical rationality that is the engineer's stock-in-trade requir[ing] the calculation of means for the realization of given ends. But it requir[ing] no broad insight into those ends or their consequences". This condition has often led to a perceived technical mindset that according to Florman (1976), draws upon "the comfort that comes with the total absorption in a mechanical environment. The world becomes reduced and manageable, controlled and unchaotic".In a relatively short period of time, ICT has been radically transformed in both its capabilities and reach. Specifically, within the context of this event, the permeation of digital technologies into nearly every aspect of bioengineering and healthcare delivery have broken down the borders between technological pursuits and the larger dynamics of society. This has in turn has produced, according to Williams (2000) a discipline that has "evolved into an open-ended Profession of Everything in a world where technology shades into science, into art, and into management, with no strong institutions to define an overarching mission". Within ICT, H.C. von Baeyer (2003) affirms this status in noting "the frustration of engineers who have at their disposal a variety of methods for measuring the amount of information in a message, but to none deal with its meaning".

Delivery of Health Care↗
PubMedDate not supplied

Using hyperaccumulator plants to phytoextract soil Ni and Cd.

Two strategies of phytoextraction have been shown to have promise for practical soil remediation: domestication of natural hyperaccumulators and bioengineering plants with the genes that allow natural hyperaccumulators to achieve useful phytoextraction. Because different elements have different value, some can be phytomined for profit and others can be phytoremediated at lower cost than soil removal and replacement. Ni phytoextraction from contaminated or mineralized soils offers economic return greater than producing most crops, especially when considering the low fertility or phytotoxicity of Ni rich soils. Only soils that require remediation based on risk assessment will comprise the market for phytoremediation. Improved risk assessment has indicated that most Zn + Cd contaminated soils will not require Cd phytoextraction because the Zn limits practical risk from soil Cd. But rice and tobacco, and foods grown on soils with Cd contamination without corresponding 100-fold greater Zn contamination, allow Cd to readily enter food plants and diets. Clear evidence of human renal tubular dysfunction from soil Cd has only been obtained for subsistence rice farm families in Asia. Because of historic metal mining and smelting, Zn + Cd contaminated rice soils have been found in Japan, China, Korea, Vietnam and Thailand. Phytoextraction using southern France populations of Thlaspi caerulescens appears to be the only practical method to alleviate Cd risk without soil removal and replacement. The southern France plants accumulate 10-20-fold higher Cd in shoots than most T. caerulescens populations such as those from Belgium and the UK. Addition of fertilizers to maximize yield does not reduce Cd concentration in shoots; and soil management promotes annual Cd removal. The value of Cd in the plants is low, so the remediation service must pay the costs of Cd phytoextraction plus profits to the parties who conduct phytoextraction. Some other plants have been studied for Cd phytoextraction, but annual removals are much lower than the best T. caerulescens. Improved cultivars with higher yields and retaining this remarkable Cd phytoextraction potential are being bred using normal plant breeding techniques.

Biodegradation, Environmental↗
PubMed2005

From stem cells to insulin-producing cells: towards a bioartificial endocrine pancreas.

The total absence or low production of insulin by beta-cells avoids a proper control of glycemia forcing diabetic people to daily insulin injection for survival. Islet transplantation represents a hallmark in the cure of diabetes and has been successfully applied to more than 400 patients, resulting in insulin independency for periods longer than 4 years. However, transplantation trials for diabetes have to face the scarcity of islets from cadaveric donors. Therefore, the finding of renewable sources of cells could circumvent this problem. In this respect, embryonic or adult stem cells are representing an interesting alternative. Stem cells display robust proliferation and the plasticity to differentiate to other cell types, including insulin-containing cells. The current therapeutical use in the future of bioengineered insulin-secreting cells derived from stem cells needs at present to fulfill several criteria. These criteria concern to the type of stem cell to be used as starting biomaterial (embryonic or adult), the in vitro differentiation protocol applied, the functional phenotype reached for the final cell product and the transplantation associated problems (likely immune rejection and tumor formation). This review will try to focus on these different aspects in order to emphasize in the key points to consider for designing unified strategies for diabetes cell therapy.

Bioartificial Organs↗
PubMed2005

Use of autologous tissue engineered skin to treat porcine full-thickness skin defects.

OBJECTIVE: To explore a feasible method to repair full-thickness skin defects utilizing tissue engineered techniques. METHODS: The Changfeng hybrid swines were used and the skin specimens were cut from the posterior limb girdle region, from which the keratinocytes and fibroblasts were isolated and harvested by trypsin, EDTA, and type II collagenase. The cells were seeded in Petri dishes for primary culture. When the cells were in logarithmic growth phase, they were treated with trypsin to separate them from the floor of the tissue culture dishes. A biodegradable material, Pluronic F-127, was prefabricated and mixed with these cells, and then the cell-Pluronic compounds were seeded evenly into a polyglycolic acid (PGA). Then the constructs were replanted to the autologous animals to repair the full-thickness skin defects. Histology and immunohistochemistry of the neotissue were observed in 1, 2, 4, and 8 postoperative weeks. RESULTS: The cell-Pluronic F-127-PGA compounds repaired autologous full-thickness skin defects 1 week after implantation. Histologically, the tissue engineered skin was similar to the normal skin with stratified epidermis overlying a moderately thick collageneous dermis. Three of the structural proteins in the epidermal basement membrane zone, type IV collagen, laminin, and type VII collagen were detected using immunohistochemical methods. CONCLUSIONS: By studying the histology and immunohistochemistry of the neotissue, the bioengineered skin graft holds great promise for improving healing of the skin defects.

Animals↗
PubMed2005

Materials characterisation of Biomedical tents.

This article reviews the use of materials characterisation to optimise the bioengineering and manufacturing of stents and thereby provide assurance of performance in clinical applications. The capabilities of today's sophisticated techniques are described.

Biocompatible Materials↗
PubMed2006

The effect of osteogenic medium on the adhesion of rat bone marrow stromal cell to the hydroxyapatite.

OBJECTIVE: To investigate the adhesive properties of bone marrow stromal cell (BMSC) on the hydroxyapatite (HA) particles and analyze their behavior. METHODS: The study took place in the Department of the Histology and Embryology, Celal Bayar University, Manisa and in the Department of Bioengineering, Ege University, Izmir, Turkey between 2004 and 2005. We cultured BMSC from the mature rat tibia and differentiated to the osteoblasts by osteogenic medium. The BMSCs were subcultured and were taken to the HA substrate. We measured their proliferation capacity and viability with MTT assay using the spectrophotometric method. Furthermore, we identified the osteoblast-like cells by immunohistochemical staining of osteonectin and osteocalcin and we analyzed the behavior of the cells on different sized HA particles by SEM at the end of 3 days incubation. RESULTS: Osteogenic medium caused the proliferation capacity of BMSC to speed up and the effects appeared earlier. We confirmed the osteoblastic differentiation by staining of most cells with osteoblastic markers. Subcultured cells were similarly adhesive to the HA particles and the osteogenic medium did not alter this behavior. They spread on the substrate similarly. Most of the cells demonstrated the cytoplasmic protrusion. Morphology of the cells did not change much with or without osteogenic medium. Different sizes of HA particles did not affect the adhesive properties of these cells except HA gel. The spreading and attachment ratios of the cells on HA gel were more than the others CONCLUSION: We found that there was heterogeneity in BMSC on differentiation capacity to the osteoblast, which was a sign of a subpopulation. Adhesive cells showed similar morphology and behavior under the effect of osteogenic medium. The only difference was the spreading capacity on the HA gel where cell used this substrate more effectively for adhesion.

Animals↗
PubMed2006

Risk factors associated with healing chronic diabetic foot ulcers: the importance of hyperglycemia.

Diabetic foot ulcer management presents a significant challenge for wound care clinicians; numerous approaches to encourage healing in these difficult wounds have been explored. To determine risk factors related to diabetic foot ulcer time to healing and closure, a secondary analysis of data from a prospective randomized study involving 245 patients treated with a bioengineered human dermal substitute (n = 130) or control treatment (n = 115) was conducted. Analyzed variables included age, race, gender, ulcer duration, initial ulcer size, initial hemoglobin (HgbA1c), average HgbA1c, change in HgbA1c, diabetes type, average hours of weight-bearing, study ulcer infection, history of smoking or alcohol use, and laboratory values. Time to healing was significantly affected by initial ulcer size (risk ratio 0.75, confidence interval 0.59-0.96), gender (risk ratio 2.01, confidence interval 1.20-3.40), and wound infection during the study (risk ratio 2.9, confidence interval 1.45-4.22). Initial ulcer size (>2 cm2), male gender, and an episode of infection during the study were associated with an increased risk of nonclosure after 12 weeks of care (P <0.05). In patients whose HgbA1C increased during the study (n = 101), 20.7% of all wounds and 21% of dermal substitute-managed wounds (n = 105) healed; whereas, in patients whose HgbA1C levels remained stable or decreased, 26.3% of all wounds and 47% of dermal substitute-managed wounds healed (P <0.05). Female gender, small ulcer size, and the absence of infection were found to have a positive effect on healing all diabetic foot ulcers; improved glucose control had a significant effect on healing wounds managed with the dermal substitute only. This is the first diabetic foot ulcer study to find a relationship between hyperglycemia and wound healing. Further research into factors that improve healing of wounds, including diabetic foot ulcers, is warranted.

Chronic Disease↗
PubMed1991

Evaluation of vulvar irritancy potential of a menstrual pad containing sodium bicarbonate in short-term application.

The effect on the skin of menstrual pads containing sodium bicarbonate as a fragrance substitute and of sodium bicarbonate alone was studied in 50 healthy women. Skin changes were monitored by transepidermal water loss, capacitance, laser Doppler flowmetry, skin surface pH and visual scoring. No clinical signs developed after the volunteers had been patched with the menstrual pads for 24 hours. No subclinical vulvar skin irritant reactions were observed with bioengineering methods. The menstrual pads containing sodium bicarbonate as a deodorant did not significantly affect the vulva in short-term use.

Bandages↗