Comparison of ballistic impact effects between biological tissue and gelatin.

PubMed

Jin, Yongxi; Mai, Ruimin; Wu, Cheng; Han, Ruiguo; Li, Bingcang

2018-02-01

Gelatin is commonly used in ballistic testing as substitute for biological tissue. Comparison of ballistic impact effects produced in the gelatin and living tissue is lacking. The work in this paper was aimed to compare the typical ballistic impact effects (penetration trajectory, energy transfer, temporary cavity) caused by 4.8mm steel ball penetrating the 60kg porcine hind limbs and 10wt% gelatin. The impact event in the biological tissue was recorded by high speed flash X-ray machine at different delay time, while the event in the gelatin continuously recorded by high speed video was compared to that in the biological tissue. The collected results clearly displayed that the ballistic impact effects in the muscle and gelatin were similar for the steel ball test; as for instance, the projectile trajectory in the two targets was basically similar, the process of energy transfer was highly coincident, and the expansion of temporary cavity followed the same pattern. This study fully demonstrated that choosing gelatin as muscle simulant was reasonable. However, the maximum temporary cavity diameter in the gelatin was a little larger than that in the muscle, and the expansion period of temporary cavity was longer in the gelatin. Additionally, the temporary cavity collapse process in the two targets followed different patterns, and the collapse period in the gelatin was two times as long as that in the muscle. Copyright © 2017 Elsevier Ltd. All rights reserved.

Funding antiretroviral treatment for HIV-positive temporary residents in Australia prevents transmission and is inexpensive.

PubMed

Gray, Richard T; Watson, Jo; Cogle, Aaron J; Smith, Don E; Hoy, Jennifer F; Bastian, Lisa A; Finlayson, Robert; Drummond, Fraser M; Whittaker, Bill; Law, Matthew G; Petoumenos, Kathy

2018-02-01

Background The aim of this study is to estimate the reduction in new HIV infections and resultant cost outcomes of providing antiretroviral treatment (ART) through Australia's 'universal access' health scheme to all temporary residents with HIV infection living legally in Australia, but currently deemed ineligible to access subsidised ART via this scheme. A mathematical model to estimate the number of new HIV infections averted and the associated lifetime costs over 5 years if all HIV-positive temporary residents in Australia had access to ART and subsidised medical care was developed. Input data came from a cohort of 180 HIV-positive temporary residents living in Australia who are receiving free ART donated by pharmaceutical companies for up to 4 years. Expanding ART access to an estimated total 450 HIV+ temporary residents in Australia for 5 years could avert 80 new infections. The model estimated the total median discounted (5%) cost for ART and associated care to be A$36million, while the total savings in lifetime-discounted costs for the new infections averted was A$22million. It is estimated that expanded access to ART for all HIV-positive temporary residents in Australia will substantially reduce HIV transmission to their sexual partners at little additional cost. In the context of Australia's National HIV strategy and Australia's endorsement of global goals to provide universal access to ART for all people with HIV, this is an important measure to remove inequities in the provision of HIV-related treatment and care.

76 FR 81059 - Guidance Regarding Deduction and Capitalization of Expenditures Related to Tangible Property

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-27

...This document contains temporary regulations that provide guidance on the application of sections 162(a) and 263(a) of the Internal Revenue Code to amounts paid to acquire, produce, or improve tangible property. The temporary regulations clarify and expand the standards in the current regulations under sections 162(a) and 263(a) and provide certain bright-line tests (for example, a de minimis rule for certain acquisitions) for applying these standards. The temporary regulations also provide guidance under section 168 regarding the accounting for, and dispositions of, property subject to section 168. The temporary regulations also amend the general asset account regulations. The temporary regulations will affect all taxpayers that acquire, produce, or improve tangible property. The text of the temporary regulations also serves as the text of proposed regulations set forth in the notice of proposed rulemaking on this subject appearing elsewhere in this issue of the Federal Register.

Modeling of the metallic port in breast tissue expanders for photon radiotherapy.

PubMed

Yoon, Jihyung; Xie, Yibo; Heins, David; Zhang, Rui

2018-03-30

The purpose of this study was to model the metallic port in breast tissue expanders and to improve the accuracy of dose calculations in a commercial photon treatment planning system (TPS). The density of the model was determined by comparing TPS calculations and ion chamber (IC) measurements. The model was further validated and compared with two widely used clinical models by using a simplified anthropomorphic phantom and thermoluminescent dosimeters (TLD) measurements. Dose perturbations and target coverage for a single postmastectomy radiotherapy (PMRT) patient were also evaluated. The dimensions of the metallic port model were determined to be 1.75 cm in diameter and 5 mm in thickness. The density of the port was adjusted to be 7.5 g/cm 3 which minimized the differences between IC measurements and TPS calculations. Using the simplified anthropomorphic phantom, we found the TPS calculated point doses based on the new model were in agreement with TLD measurements within 5.0% and were more accurate than doses calculated based on the clinical models. Based on the photon treatment plans for a real patient, we found that the metallic port has a negligible dosimetric impact on chest wall, while the port introduced significant dose shadow in skin area. The current clinical port models either overestimate or underestimate the attenuation from the metallic port, and the dose perturbation depends on the plan and the model in a complex way. TPS calculations based on our model of the metallic port showed good agreement with measurements for all cases. This new model could improve the accuracy of dose calculations for PMRT patients who have temporary tissue expanders implanted during radiotherapy and could potentially reduce the risk of complications after the treatment. © 2018 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

Use of cyanoacrylate glue for temporary tarsorrhaphy in children.

PubMed

Trivedi, Dipti; McCalla, Maureen; Squires, Zoe; Parulekar, Manoj

2014-01-01

Congenital anophthalmia and postenucleation socket contracture are difficult conditions that require serial socket expansion with the use of hydrogel expanders and custom-made conformers along with temporary tarsorrhaphy. The authors undertook a part prospective case review of all children undergoing temporary tarsorrhaphy using cyanoacrylate glue over a 3-year period at a tertiary specialist children's hospital. They report a series of 7 children undergoing temporary tarsorrhaphy with cyanoacrylate glue instead of the conventional suturing technique. Indications were socket expansion (n = 4), fornix deepening (n = 2), prosthesis reposition, and prolapsed conjunctiva following enucleation (n = 1).The age range was 3 weeks to 14 years (mean, 2.7 years). The glue tarsorrhaphy lasted between 0.5 and 13 weeks (mean, 4.5 weeks). There were no adverse outcomes, and the glue tarsorrhaphy was tolerated well in all cases, with relative ease of reapplication of glue in clinic. Their study demonstrates that this technique allows quick and efficient temporary tarsorrhaphy with relative ease of reapplication in a clinic setting, avoiding the need for multiple general anesthetics.

78 FR 43941 - Sunshine Act; Notice of Agency Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-22

..., Electronic Filing of Financial Reports. 4. Request from San Francisco FCU to Expand its Community Charter Boundaries. 5. Quarterly Insurance Fund Report. 6. 2013 Temporary Corporate Credit Union Stabilization Fund...

Multi-stage surgery for airway patency after metallic stent removal in benign laryngotracheal airway disease in two adolescents.

PubMed

Coordes, Annekatrin; Todt, Ingo; Ernst, Arne; Seidl, Rainer O

2013-05-01

Laryngotracheal stents may damage the highly complex laryngeal structures, impair voice and swallowing functions and cause tissue ingrowths, thereby necessitating airway patency interventions. In benign airway disease, the number of adolescents with laryngotracheal stents is therefore limited. We present two cases of laryngeal metallic stent placement following benign airway disease. Two adolescents presented with severe dyspnea and self-expandable metallic stent placement after benign laryngotracheal stenoses. Granulation tissue ingrowths required additional surgical interventions every 6-8 weeks to recanalize the stent lumen. We performed multi-stage surgery including removal of the embedded stent, segmental resection of the stenotic area, end-to-end-anastomosis and laryngotracheal reconstruction respectively, to achieve patent airway without tracheal cannulation. Montgomery T-tubes were temporarily inserted to bridge the complex reconstructions. In both adolescents, we achieved successful removal of the embedded stent and patent airway. Bilateral vocal fold paralysis required additional surgery to improve the final airway patency and vocal rehabilitation. Stent removal, segmental resection and laryngotracheal reconstruction provide the achievement of patent airway and allow decannulation. Temporary Montgomery T-tubes bridge complex laryngotracheal reconstructions. In benign laryngeal airway disease, stent placement should be avoided, especially in adolescents. Transfer to a specialist center should be considered prior to metallic stent implantation. In general, self-expanding tracheobronchial stents can be placed in selected patients where surgical interventions are limited. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Use of covered self-expandable stents for benign colorectal disorders in children.

PubMed

Lange, Bettina; Sold, Moritz; Kähler, Georg; Wessel, Lucas M; Kubiak, Rainer

2017-01-01

There is a lack of experience with covered self-expandable stents for benign colorectal disorders in children. Five children (4M, 1F) with a median age of 5years (range, 6months-9years) who underwent treatment with covered self-expandable plastic (SEPSs) or self-expandable metal stents (SEMSs) for a benign colorectal condition between April 2005 and November 2013 were recruited to this retrospective study. Etiologies included: anastomotic stricture with (n=1) or without (n=3) simultaneous enterocutaneous fistula, as well as an anastomotic leak associated with enterocutaneous fistula (n=1). All children suffered from either Hirschsprung's disease (n=3) or total colonic aganglionosis (Zuelzer-Wilson syndrome) (n=2). Median duration of individual stent placement was 23days (range, 1-87days). In all cases up to five different stents were placed over time. At follow-up two patients were successfully treated without further intervention. In another patient the anastomotic stricture resolved fully, but a coexisting enterocutaneous fistula persisted. Overall, three patients did not improve completely following stenting and required definite surgery. Stent-related problems were noted in all cases. There was one perforation of the colon at stent insertion. Further complications consisted of stent dislocation (n=4), obstruction (n=1), formation of granulation tissue (n=1), ulceration (n=1) and discomfort (n=3). Covered self-expandable stents enrich the armamentarium of interventions for benign colorectal disorders in children including anastomotic strictures and intestinal leaks. A stent can be applied either as an emergency procedure (bridge to surgery) or as an adjuvant treatment further to endoscopy and dilatation. Postinterventional problems are frequent but there is a potential for temporary or definite improvement following stent insertion. Copyright © 2017. Published by Elsevier Inc.

Tissue Residues, Hematological and Biochemical Effects of Tilmicosin in Broiler Chicken

PubMed Central

Elsayed, Mossad; Elkomy, Ashraf; Morad, Mohamed

2014-01-01

The aim of this study was to determine the blood and tissue concentrations profile and effect of tilmicosin on some hematological and biochemical parameters in broiler chicken. Fifty clinically healthy Hubbard chickens were orally administered 25 mg/kg BW of tilmicosin once daily for 5 consecutive days. Tissue residues of tilmicosin in slaughtered healthy chicken could not be detected by microbiological assay in all tested tissues except in lung (at 96 hours) and liver and kidneys (at 72 hours) after last administration. Tilmicosin caused temporary decrease in the RBCs and WBCs counts and has no effect on hemoglobin (Hb) and packed cell volume concentration (PCV). Also, the effect of tilmicosin on some biochemical parameters was as follows: the concentrations of creatinine, uric acid, electrolytes (sodium, potassium, and calcium), glucose, AST, ALT, ALP, and HDL-cholesterol in the serum of treated chicken did not change in response to the repeated oral administration of tilmicosin. There were only a temporary significant decrease in total protein and albumin concentrations and a significant increase in cholesterol and triglycerides concentrations. Chicken must not be slaughtered before 4 days from the stopping of tilmicosin administration. Tilmicosin makes temporary changes on hematological and biochemical parameters in broiler chicken. PMID:24808972

Tissue residues, hematological and biochemical effects of tilmicosin in broiler chicken.

PubMed

Elsayed, Mossad; Elkomy, Ashraf; Aboubakr, Mohamed; Morad, Mohamed

2014-01-01

The aim of this study was to determine the blood and tissue concentrations profile and effect of tilmicosin on some hematological and biochemical parameters in broiler chicken. Fifty clinically healthy Hubbard chickens were orally administered 25 mg/kg BW of tilmicosin once daily for 5 consecutive days. Tissue residues of tilmicosin in slaughtered healthy chicken could not be detected by microbiological assay in all tested tissues except in lung (at 96 hours) and liver and kidneys (at 72 hours) after last administration. Tilmicosin caused temporary decrease in the RBCs and WBCs counts and has no effect on hemoglobin (Hb) and packed cell volume concentration (PCV). Also, the effect of tilmicosin on some biochemical parameters was as follows: the concentrations of creatinine, uric acid, electrolytes (sodium, potassium, and calcium), glucose, AST, ALT, ALP, and HDL-cholesterol in the serum of treated chicken did not change in response to the repeated oral administration of tilmicosin. There were only a temporary significant decrease in total protein and albumin concentrations and a significant increase in cholesterol and triglycerides concentrations. Chicken must not be slaughtered before 4 days from the stopping of tilmicosin administration. Tilmicosin makes temporary changes on hematological and biochemical parameters in broiler chicken.

Tissue regeneration during tissue expansion and choosing an expander

PubMed Central

Agrawal, K.; Agrawal, S.

2012-01-01

This paper reviews the various aspects of tissue regeneration during the process of tissue expansion. “Creep” and mechanical and biological “stretch” are responsible for expansion. During expansion, the epidermis thickens, the dermis thins out, vascularity improves, significant angiogenesis occurs, hair telogen phase becomes shorter and the peripheral nerves, vessels and muscle fibres lengthen. Expansion is associated with molecular changes in the tissue. Almost all these biological changes are reversible after the removal of the expander.This study is also aimed at reviewing the difficulty in deciding the volume and dimension of the expander for a defect. Basic mathematical formulae and the computer programmes for calculating the dimension of tissue expanders, although available in the literature, are not popular. A user-friendly computer programme based on the easily available Microsoft Excel spread sheet has been introduced. When we feed the area of defect and base dimension of the donor area or tissue expander, this programme calculates the volume and height of the expander. The shape of the expander is decided clinically based on the availability of the donor area and the designing of the future tissue movement. Today, tissue expansion is better understood biologically and mechanically. Clinical judgement remains indispensable in choosing the size and shape of the tissue expander. PMID:22754146

Comparison of Temporary Open Arterial Revascularization Using Stent Grafts vs. Standard Vascular Shunts in a Porcine (Sus scrofa) Model

DTIC Science & Technology

2017-01-24

Objectives: Open surgical reconstruction using expanded polytetrafluoroethylene stent grafts to create a sutureless anastomosis is an alternative to...French Argyle shunt was inserted into one randomly assigned artery, with a self-expanding ePTFE stent deployed in the other. Arterial flow measurements...for histopathology were obtained during the terminal procedure. Results: Angiography revealed no difference in patency at 72 hours. The stent grafts

Tissue Expander versus Tissue Expander and Latissimus Flap in Morbidly Obese Breast Reconstruction Patients

PubMed Central

Adams, Robert L.; Chandler, Robert G.; Parks, Joseph

2015-01-01

Background: Immediate postmastectomy breast reconstruction in morbidly obese patients represents a challenge because neither prosthetic nor abdominal-based options may be suitable. Methods: This study compared a previously published cohort of immediate prosthetic reconstruction of 346 patients (511 breasts) of whom 49 patients (67 breasts) were morbidly obese (defined as a body mass index > 35) with a morbidly obese patient population whose breasts were reconstructed immediately following postmastectomy with latissimus flap and tissue expander (21 patients and 22 breasts) in the same time period. The preoperative risk factors of mastectomy such as tobacco use, diabetes, and prior radiation and the postoperative complications of mastectomy such as skin necrosis, seroma, and prosthesis loss were examined. The explantation of the tissue expander provided a defined endpoint of reconstruction failure. Results: The average body mass index in the tissue expander/implant group and in the latissimus flap plus tissue expander/implant group was 40.9 and 40.1, respectively. The risk profile of diabetes and tobacco use was similar in both groups. Fifteen of the 67 breasts (22.3%) of the tissue expander/implant group and 15 of the 23 breasts (65.2%) of the latissimus flap group had received prior radiation. The prosthesis loss was 13 of 67 breasts (19.4%) that had tissue-expander–alone reconstruction and 1 of 22 (4.8%) in the latissimus group that had tissue expander reconstruction. Modification of donor-site incision and skin-island location in the latissimus group of patients can minimize scar deformity. Conclusion: The loss rate in immediate postmastectomy reconstruction in morbidly obese patients with latissimus flap plus tissue expander was substantially lower than the loss rate in those with breast reconstructed with tissue expander alone. PMID:25878934

Effects of the temporary placement of a self-expandable metallic stent in benign pyloric stenosis.

PubMed

Choi, Won Jae; Park, Jong-Jae; Park, Jain; Lim, Eun-Hye; Joo, Moon Kyung; Yun, Jae-Won; Noh, Hyejin; Kim, Sung Ho; Choi, Woo Seok; Lee, Beom Jae; Kim, Ji Hoon; Yeon, Jong Eun; Kim, Jae Seon; Byun, Kwan Soo; Bak, Young-Tae

2013-07-01

The use of self-expandable metallic stents (SEMS) is an established palliative treatment for malignant stenosis in the gastrointestinal tract; therefore, its application to benign stenosis is expected to be beneficial because of the more gradual and sustained dilatation in the stenotic portion. We aimed in this prospective observational study to evaluate the efficacy and safety of temporary SEMS placement in benign pyloric stenosis. Twenty-two patients with benign stenosis of the prepylorus, pylorus, and duodenal bulb were enrolled and underwent SEMS placement. We assessed symptom improvement, defined as an increase of at least 1 degree in the gastric-outlet-obstruction scoring system after stent insertion. No major complications were observed during the procedures. After stent placement, early symptom improvement was achieved in 18 of 22 patients (81.8%). During the follow-up period (mean 10.2 months), the stents remained in place successfully for 6 to 8 weeks in seven patients (31.8%). Among the 15 patients (62.5%) with stent migration, seven (46.6%) showed continued symptomatic improvement without recurrence of obstructive symptoms. Despite the symptomatic improvement, temporary SEMS placement is premature as an effective therapeutic tool for benign pyloric stenosis unless a novel stent is developed to prevent migration.

Effects of the Temporary Placement of a Self-Expandable Metallic Stent in Benign Pyloric Stenosis

PubMed Central

Choi, Won Jae; Park, Jain; Lim, Eun-Hye; Joo, Moon Kyung; Yun, Jae-Won; Noh, Hyejin; Kim, Sung Ho; Choi, Woo Seok; Lee, Beom Jae; Kim, Ji Hoon; Yeon, Jong Eun; Kim, Jae Seon; Byun, Kwan Soo; Bak, Young-Tae

2013-01-01

Background/Aims The use of self-expandable metallic stents (SEMS) is an established palliative treatment for malignant stenosis in the gastrointestinal tract; therefore, its application to benign stenosis is expected to be beneficial because of the more gradual and sustained dilatation in the stenotic portion. We aimed in this prospective observational study to evaluate the efficacy and safety of temporary SEMS placement in benign pyloric stenosis. Methods Twenty-two patients with benign stenosis of the prepylorus, pylorus, and duodenal bulb were enrolled and underwent SEMS placement. We assessed symptom improvement, defined as an increase of at least 1 degree in the gastric-outlet-obstruction scoring system after stent insertion. Results No major complications were observed during the procedures. After stent placement, early symptom improvement was achieved in 18 of 22 patients (81.8%). During the follow-up period (mean 10.2 months), the stents remained in place successfully for 6 to 8 weeks in seven patients (31.8%). Among the 15 patients (62.5%) with stent migration, seven (46.6%) showed continued symptomatic improvement without recurrence of obstructive symptoms. Conclusions Despite the symptomatic improvement, temporary SEMS placement is premature as an effective therapeutic tool for benign pyloric stenosis unless a novel stent is developed to prevent migration. PMID:23898381

Temporary arthrodesis using fixator rods in two-stage revision of septic knee prothesis with severe bone and tissue defects.

PubMed

Röhner, Eric; Pfitzner, Tilman; Preininger, Bernd; Zippelius, Timo; Perka, Carsten

2016-01-01

The present study describes a new temporary arthrodesis procedure, which aims for septic knee prosthesis replacement, in particular for larger bone and soft tissue defects. Our technique offers high stability and full weight-bearing capacity of the knee joint. The study included 16 patients with major bone defects (AORI type IIb or greater) after receiving a radical debridement and a septic two-stage revision total knee arthroplasty. After removing the infected prosthesis and debridement, two AO fixator rods were positioned into the intramedullary space of the femur and tibia. Subsequently, both rods were joined tube-to-tube and adjusted in the center of the knee joint. Finally, the whole cavity of the knee joint was filled with PMMA. The number of previous surgeries, bacterial spectrum, risk factors for further infection and reinfection rates was recorded. Immediately after the temporary arthrodesis, radiographs of the knee with the enclosed spacers were taken in order to compare to previous radiographs and avoiding to miss possible spacer loosening. Nine of sixteen patients underwent more than two revision surgeries before receiving our new arthrodesis technique. No cases of spacer loosening were observed in all 16 patients; further, there were no peri-implant fractures, and four persistent infections were noted. Temporary arthrodesis using AO fixator rods offers a high stability without loosening. Its potential to replace conventional augmentation techniques should be taken into account, particularly in the case of larger bone and tissue defects. In clinical practice, the cemented spacer using AO fixator rods could be an alternative technique for temporary knee arthrodesis after septic debridement. Retrospective case series, Level IV.

[Reconstruction of facial soft tissue defects with pedicled expanded flaps].

PubMed

Yangqun, Li; Yong, Tang; Wen, Chen; Zhe, Yang; Muxin, Zhao; Lisi, Xu; Chunmei, Hu; Yuanyuan, Liu; Ning, Ma; Jun, Feng; Weixin, Wang

2014-09-01

To investigate the application of pedicled expanded flaps for the reconstruction of facial soft tissue defects. The expanded skin flaps, pedicled with orbicularis oculi muscle, submental artery, the branch of facial artery, superficial temporal artery, interior upper arm artery, had similar texture and color as facial soft tissue. The pedicled expanded flaps have repaired the facial soft tissue defects. Between Jan. 2003 to Dec. 2013, 157 cases with facial soft tissue defects were reconstructed by pedicled expanded flaps. Epidermal necrosis happened at the distal end of 8 expanded flaps, pedicled with interior upper arm artery(4 cases), orbicularis oculi muscle(3 cases) and submental artery(1 case), which healed spontaneously after dressing. All the other flaps survived completely with similar color and inconspicuous scar. 112 cases were followed up for 8 months to 8 years. Satisfactory results were achieved in 75 cases. 37 cases with hypertrophic scar at incisions need secondary operation. Island pedicled expanded flap with similar texture and color as facial soft tissue is suitable for facial soft tissue defects. The facial extra-incision and large dog-ear deformity could be avoided.

Fecal transplant policy and legislation

PubMed Central

Vyas, Dinesh; Aekka, Apoorva; Vyas, Arpita

2015-01-01

Fecal microbiota transplantation (FMT) has garnered significant attention in recent years in the face of a reemerging Clostridium difficile (C. difficile) epidemic. Positive results from the first randomized control trial evaluating FMT have encouraged the medical community to explore the process further and expand its application beyond C. difficile infections and even the gastrointestinal domain. However promising and numerous the prospects of FMT appear, the method remains limited in scope today due to several important barriers, most notably a poorly defined federal regulatory policy. The Food and Drug Administration has found it difficult to standardize and regulate the administration of inherently variable, metabolically active, and ubiquitously available fecal material. The current cumbersome policy, which classifies human feces as a drug, has prevented physicians from providing FMT and deserving patients from accessing FMT in a timely fashion, and subsequent modifications seem only to be temporary. The argument for reclassifying fecal material as human tissue is well supported. Essentially, this would allow for a regulatory framework that is sufficiently flexible to expand access to care and facilitate research, but also appropriately restrictive and centralized to ensure patient safety. Such an approach can facilitate the advancement of FMT to a more refined, controlled, and aesthetic process, perhaps in the form of a customized and well-characterized stool substitute therapy. PMID:25574076

Conjunctival Expansion Using a Subtenon's Silicone Implant in New Zealand White Rabbits

PubMed Central

Yoon, Ie-na; Lee, Dong-hoon

2007-01-01

Purpose In the field of ophthalmology, the conjunctival autograft is a useful therapeutic material in many cases, but the small size of the autograft is a disadvantage. Therefore, we evaluated the feasibility of taking an expanded sample of conjunctival tissue using a subtenon's silicone implant. Materials and Methods We included a total of nine rabbits; eight rabbits were operative cases, and one was a control. A portion of conjunctival tissue from the control rabbit, which did not undergo surgery, was dissected and examined to determine whether it was histologically different from the experimental group. The surgical procedure was performed on eight rabbits via a subtenon's insertion of a silicone sponge in the left superior-temporal portion; after surgery, we dropped antibiotics into the eyes. We sacrificed a pair of rabbits every three days (on days 3, 6, 9, and 12) after surgery, removed the expanded conjunctival tissues with the silicone sponge implants, and measured their sizes. Results The mean size of the expanded conjunctival tissues was 194.4 mm2. On the third day, we were able to harvest a 223.56 mm2 section of conjunctival tissue, which was the most expanded sample of tissue in the study. On the twelfth day, we removed a 160.38 mm2 section of conjunctival tissue, which was the least expanded sample of tissue. Statistically, there were no significant differences in the mean dimensions of the expanded conjunctival tissues for each time period. Microscopic examinations showed no histological differences between the expanded conjunctival tissues and the normal conjunctival tissues. Conclusion The results reveal that this procedure is a useful method to expand the conjunctiva for grafting and transplantation. PMID:18159586

An alternative method of using an interpositional silicone sheet in tissue expansion.

PubMed

Borman, Huseyin; Deniz, Murat; Bahar, Taner; Bilezikci, Banu; Tufan, Hale; Haberal, Mehmet

2009-05-01

To reduce the rate of complications in tissue expansion, we placed a silicone sheet between the expander and the tissue above it in a rat model. In the rats in group 1 (n = 10), the expanders were placed under the dorsal skin. The expanders were inflated with up to 45 mL of saline solution. In group 2 (n = 10), a silicone sheet was inserted between the tissue expander and the skin, after which the procedure used in group 1 was performed. The blood flow was reduced at the dome (center [C]) of the expanders in groups 1C and 2C to a degree greater than that in the expanded skin in groups 1 and 2 far periphery. However, the flow was significantly better in group 2C than in group 1C. Histologic analysis showed that the dermal and capsular tissues were significantly thicker in group 2C than in group 1C. In our opinion, placing a silicone sheet between the expander and the tissue above it seems to be beneficial. This may reduce the incidence of complications, especially the expander extrusion in this model.

Dosimetry around metallic ports in tissue expanders in patients receiving postmastectomy radiation therapy: an ex vivo evaluation.

PubMed

Moni, Janaki; Graves-Ditman, Maria; Cederna, Paul; Griffith, Kent; Krueger, Editha A; Fraass, Benedick A; Pierce, Lori J

2004-01-01

Postmastectomy breast reconstruction can be accomplished utilizing tissue expanders and implants. However, in patients who require postoperative radiotherapy, the complication rate with tissue expander/implant reconstruction can exceed 50%. One potential cause of this high complication rate may be the metallic port in the tissue expander producing altered dosimetry in the region of the metallic device. The purpose of this study was to quantify the radiation dose distribution in the vicinity of the metallic port and determine its potential contribution to this extremely high complication rate. The absolute dosimetric effect of the tissue expander's metallic port was quantified using film and thermoluminescent dosimetry (TLD) studies with a single beam incident on a metallic port extracted from an expander. TLD measurements were performed at 11 reproducible positions on an intact expander irradiated with tangential fields. A computed tomography (CT)-based treatment plan without inhomogeneity corrections was used to derive expected doses for all TLD positions. Multiple irradiation experiments were performed for all TLD data. Confidence intervals for the dose at TLD sites with the metallic port in place were compared to the expected dose at the site without the metallic port. Film studies did not reveal a significant component of scatter around the metallic port. TLD studies of the extracted metallic port revealed highest doses within the casing of the metallic port and no consistent increased dose at the surface of the expander. No excess dose due to the metallic port in the expander was noted with the phantom TLD data. Based upon these results, it does not appear that the metallic port in tissue expanders significantly contributes to the high complication rate experienced in patients undergoing tissue expander breast reconstruction and receiving radiation therapy. Strategies designed to reduce the breast reconstruction complication rate in this clinical setting will need to focus on factors other than adjusting the dosimetry around the tissue expander metallic port.

77 FR 34785 - Substantial Business Activities

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-12

.... Miller, Deputy Commissioner for Services and Enforcement. Approved: June 4, 2012. Emily S. McMahon... comment also recommended different safe harbors depending on the extent of the expanded affiliated group's... Procedure Act (5 U.S.C. chapter 5) does not apply to the 2012 temporary regulations and because the...

The use of a tissue expander to enlarge a graft for surgical treatment of a pressure ulcer in a quadriplegic. Case report.

PubMed

Braddom, R L; Leadbetter, M G

1989-04-01

This case reports the use of a tissue expander to facilitate the surgical closure of a decubitus ulcer in a spinal cord injured quadriplegic. The patient is a 42-year-old man with chronic nonhealing of a right ischial pressure ulcer. It had required a flap rotation and partial ischiectomy in the remote past that had been problem-free for many years. The patient subsequently required the placement of a new flap, but insufficient tissue was available to close the wound with the hip in 90 degrees of flexion. Closing the wound with the hip in extension merely led to breakdown when the hip was put in the 90 degrees of flexion required for the sitting position. The problem was solved by using a tissue expander to increase the available soft tissue. A tissue expander was inserted and gradually expanded over a period of weeks by injecting it with fluid. It was then removed, and the expanded tissue that had grown over it allowed closure of the wound without tension on the tissues with the hip in flexion. The patient subsequently returned to the sitting position and his work as a computer programmer. Tissue expanders are commonly used in breast reconstruction, but have found many other uses in plastic surgery over the last decade. It is felt that tissue expansion techniques should not be the primary surgery treatment of decubitus ulcers, but can be used in difficult cases like this one to provide additional tissue.

Using TANF to Finance Out-of-School Time Initiatives

ERIC Educational Resources Information Center

Relave, Nanette; Flynn-Khan, Margaret

2007-01-01

This report addresses how the Temporary Assistance for Needy Families (TANF) program can be an important source of funding for maintaining, improving, and expanding out-of-school time initiatives. The report is designed to help policymakers and program developers understand the opportunities and challenges of effectively using TANF funding to…

Tissue expanders with a focus on extremity reconstruction.

PubMed

Arain, Abdul R; Cole, Keegan; Sullivan, Christopher; Banerjee, Samik; Kazley, Jillian; Uhl, Richard L

2018-02-01

Acute traumatic or surgical wounds that cannot be primarily closed often cause substantial morbidity and mortality. This often leads to increased costs from higher material expenses, more involved nursing care, and longer hospital stays. Advancements in soft tissue expansion has made it a popular alternative to facilitate early closure without the need for more complicated plastic surgical procedures. Areas covered: In this review, we briefly elaborate on the history and biomechanics of tissue expansion and provide comprehensive descriptions of traditional internal tissue expanders and a variety of contemporary external tissue expanders. We describe their uses, advantages, disadvantages, and clinical outcomes. The majority of articles reviewed include case series with level IV evidence. Outcome data was collected for studies after 1990 using PubMed database. Expert commentary: An overall reduction in cost, time-to-wound closure, hospital length-of-stay, and infection rate may be expected with most tissue expanders. However, further studies comparing outcomes and cost-effectiveness of various expanders may be beneficial. Surgeons should be aware of the wide array of tissue expanders that are commercially available to individualize treatment based on thorough understanding of their advantages and disadvantages to optimize outcomes. We predict the use of external expanders to increase in the future and the need for more invasive procedures such as flaps to decrease.

Immediate two-stage prosthetic breast reconstruction failure: radiation is not the only culprit.

PubMed

Lam, Thomas C; Borotkanics, Robert; Hsieh, Frank; Salinas, James; Boyages, John

2018-03-15

Immediate prosthetic breast reconstruction produces a satisfactory aesthetic result with high levels of patient satisfaction. However, with the broader indication for post-mastectomy adjuvant radiation, many patients are advised against immediate breast reconstruction because of concerns of implant loss and infection particularly as most patients also require chemotherapy. This retrospective cohort study examines outcomes for patients who underwent immediate two-stage prosthetic breast reconstruction after mastectomy with or without adjuvant chemotherapy or radiotherapy (RT). Between 1998 and 2010, 452 patients undergoing two-stage prosthetic immediate breast reconstruction involving a total of 562 breasts were included in this study. Stage one was defined as insertion of the temporary expander and stage two insertion of the final silicone implant. Post-operative adjuvant radiotherapy was recommended with tissue expander in-situ for 114 patients. Complications, including loss of prosthesis, seroma and infection were recorded and analysed. Cosmetic result was assessed using a 4-point scale. Post-operative prosthesis loss was 2.7%, 5.3% for patients undergoing adjuvant chemotherapy increasing to 11.3% for patients receiving chemotherapy+RT. Chemotherapy and radiotherapy independently were the main, statistically significant, risk factors for expander or implant loss; IRR: 13.85 (p=0.012) and 2.23 (p=0.027), respectively. Prosthesis loss for patients undergoing combination chemotherapy+RT was also significant; IRR: 4.791 (p<0.001). These findings serve to better inform patients on risk in weighing treatment options. Post-mastectomy radiation doubles the risk of prosthesis loss over and above adjuvant chemotherapy but is an acceptable option following immediate prosthetic breast reconstruction in a multidisciplinary setting.

A reconsideration of the wounding mechanism of very high velocity projectiles--importance of projectile shape.

PubMed

Fackler, M L; Bellamy, R F; Malinowski, J A

1988-01-01

In 1976 a paper appeared which forecast "significant increases in velocities of projectiles from guns and fragments from warheads." It was postulated that the higher velocity projectiles would cause shallow wounds with wide tissue destruction on the surface--especially when striking velocity exceeded the speed of sound in tissue (about 1.5 km/sec). Other studies have not dealt with projectiles in this velocity range; the conclusions and assumptions stated in this 1976 paper have been quoted by others and accepted as fact. In a previous study, we shot blunt fragments into gelatin, but our findings did not support the proposed hypothesis that temporary cavity shape in tissue changes at velocities above the sonic speed. The temporary cavity becomes larger with increasing velocity but it does not become shallow unless the projectile fragments on impact. In the present study, we shot a series of blunt projectiles into animal tissue at velocities of 764 to 2,049 m/s. The stellate skin and muscle disruption splits from temporary cavity stretch we observed in this study are not apparent on entrance wounds from individual explosive device fragments in the living wounded. We suggest, therefore, that studies using blunt projectiles at striking velocities above 700 m/s are lacking in clinical relevance. We also compared wounds produced by pointed projectiles with those produced by blunt projectiles. The marked difference in wound morphology showed the fallacy of doing a study with blunt missiles and applying conclusions from that study to tissue disruption caused by all projectiles.

Comparison of direct site endovascular repair utilizing expandable polytetrafluoroethylene stent grafts versus standard vascular shunts in a porcine (Sus scrofa) model.

PubMed

Davidson, Anders J; Neff, Lucas P; Grayson, J Kevin; Clement, Nathan F; DeSoucy, Erik S; Simon Logan, Meryl A; Abbot, Christopher M; Sampson, James B; Williams, Timothy K

2017-09-01

The small diameter of temporary vascular shunts for vascular trauma management may restrict flow and result in ischemia or early thrombosis. We have previously reported a clinical experience with direct, open surgical reconstruction using expandable polytetrafluoroethylene stent grafts to create a "sutureless" anastomosis as an alternative to standard temporary vascular shunts. We sought to characterize patency and flow characteristics of these grafts compared with standard shunts in a survival model of porcine vascular injury. Twelve Yorkshire-cross swine received a 2-cm-long near-circumferential defect in the bilateral iliac arteries. A 14 Fr Argyle shunt was inserted into one randomly assigned artery, with a self-expanding expandable polytetrafluoroethylene stent deployed in the other. At 72 hours, conduit patency was evaluated by angiography. Arterial flow measurements were obtained at baseline, immediately after intervention, and after 72 hours via direct measurement with perivascular flow meters. Blood pressure proximal and distal to the conduits and arterial samples for histopathology were obtained during the terminal procedure. Angiography revealed no difference in patency at 72 hours (p = 1.0). While there was no difference in baseline arterial flow between arteries (p = 0.63), the stent grafts demonstrated significantly improved blood flow compared with shunts both immediately after intervention (390 ± 36 mL/min vs. 265 ± 25 mL/min, p = 0.002) and at 72 hours (261 ± 29 mL/min vs. 170 ± 36 mL/min, p = 0.005). The pressure gradient across the shunts was greater than that of the stent grafts (11.5 mm Hg [interquartile range, 3-19 mm Hg] vs. 3 mm Hg [interquartile range, 3-5 mm Hg], p = 0.013). The speed of deployment was similar between the two devices. Open "sutureless" direct site repair using commercially available stent grafts to treat vascular injury is a technically feasible strategy for damage control management of peripheral vascular injury and offers increased blood flow when compared with temporary shunts. Furthermore, stent grafts may offer improved durability to extend the window until definitive vascular repair. The combination of these traits may improve outcomes after vascular injury. Epidemiologic/Prognostic, level III.

Screening for common mental disorders and substance abuse among temporary hired cleaners in Egyptian Governmental Hospitals, Zagazig City, Sharqia Governorate.

PubMed

Abbas, R A; Hammam, R A M; El-Gohary, S S; Sabik, L M E; Hunter, M S

2013-01-01

Informal employment is common in developing countries, including Egypt. This type of employment may have significant consequences on mental health. To determine the prevalence and risk factors of common mental disorders and substance abuse among temporary hired hospital cleaners. A cross-sectional study was conducted on 242 adult temporary cleaners and 209 permanent cleaners working in 4 governmental hospitals in Zagazig City, Sharqia Governorate, Egypt. All participants were invited to complete a structured questionnaire through a semi-structured interview which included the self-reporting questionnaire 20 items (SRQ-20) and the work stress scale. Assessment of drug use included urine-based screening tests for common substances abused. The prevalence of job stress, common mental disorders and substance abuse, particularly tramadol and cannabis (Bango), was significantly higher in the studied temporary cleaners compared to permanent cleaners. Risk factors associated with increased susceptibility of the temporary cleaners to common mental disorders were family history of substance abuse, high crowding index, history of physical illness, low educational level, and smoking; while being unmarried, male sex, family history of mental disorder, age ≥40 years, smoking, and length of service ≥8 years, were associated with substance abuse among the same group. Temporary hired hospital cleaners suffered from impaired mental health more than permanent cleaners. Therefore, expanding the coverage of current laws and occupational safety and health standards to cover workers in the informal sector especially in developing countries is recommended.

Intra-oral soft tissue expansion and volume stability of onlay bone grafts.

PubMed

Abrahamsson, Peter

2011-01-01

Insufficient regeneration of missing bone and soft-tissue may present aesthetic or functional problems in patients indicated for dental implant surgery. Several techniques such as bone grafts, bone substitutes and guided tissue regeneration (GTR) have been described to rebuild a compromised alveolar ridge. Adequate soft-tissue coverage of grafted bone and titanium-mesh is important to avoid exposure which may result in loss of the bone graft. The general aim of this thesis was to evaluate use of an osmotic tissue expander for expanding intra-oral soft tissue--creating a surplus of soft tissue-- in preparation for onlay bone grafting. An experimental rabbit model was used in studies (I), (II) and (III). In (I) an osmotic soft-tissue expander was placed bilaterally on the lateral wall of the mandible via an extra-oral approach. After two weeks of expansion the rabbits were killed and specimens were collected for histology. No inflammatory reaction and no resorbtion of the cortical bone occured. The periosteum was expanded and new bone formation was seen in the edges of the expander. In (II) and (III) the expander was placed under the periosteum in the same way as in (I): bilaterally in 13 rabbits in (II) and unilaterally in 11 rabbits in (III). After two weeks of expansion the expander was identified and removed. In (II) particulated bone was placed at the recipient site protected by a titanium mesh in one site and a bio-resorbable mesh on the other site. In (III), DBBM particles and bone particles collected from the lateral border of the mandible separated by a collagen membrane was placed at the recipient site. The graft was protected by a pre-bent titanium mesh covered by a collagen membrane. After a healing period of 3 months specimens were collected for histological and SEM examination. New bone was growing in direct contact with the titanium mesh and bio resorbable mesh. The newly formed bone had the same calcium content as the mature bone in the base of the mandible. In the clinical study (IV) 20 patients were consecutively recruited and randomised into two groups. The experimental group (ten patients) had an osmotic soft tissue expander implanted. After two weeks of expansion the expander was removed and a particulated bone graft protected by a titanium mesh and a collagen membrane was fixed to the recipient site. Titanium implants were installed after a healing period of 6 months. The patients in the reference group had a bone block grafted from the anterior ramus fixated to the recipient site with one or two titanium mini screws. Implants were installed after a healing period of 6 months. A three dimensional optical measuring device was used to measure alterations in the soft tissue profile before each surgical procedure. The three-dimensional changes were then analysed on a PC. The results from the clinical study in patients confirmed the results from the experimental rabbit studies. The osmotic tissue expander expanded the soft tissue. Expander perforations of the soft tissue occurred in two patients. The optical measurements demonstrated a positive volume gain after soft tissue expansion and bone grafting. The expanded tissue could be used to cover a bone graft. There still was a risk of mesh exposure, even after soft tissue expansion, which occurred in two patients. In both groups, implants could be installed in the grafted bone in positions that would allow the crowns to fit aesthetically into the dental arch.

Placements & Salaries Survey 2010: Stagnant Salaries, Rising Unemployment

ERIC Educational Resources Information Center

Maatta, Stephanie L.

2010-01-01

"Library Journal's annual Placements & Salaries Survey, with 1,996 respondents representing 38.7% of the approximately 5160 2009 LIS graduates, found an uptick in starting salaries, but bigger bumps in part-time and temporary jobs, an expanding gender gap, setbacks for minority graduates, and a drop in the number of total graduates. On the up…

76 FR 21253 - Safety Zone; M/V DAVY CROCKETT, Columbia River

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-15

...-AA00 Safety Zone; M/V DAVY CROCKETT, Columbia River AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The U.S. Coast Guard is extending and expanding the emergency safety zone established on... January 28, 2011. The safety zone is necessary to help ensure the safety of the response workers and...

21 CFR 346.50 - Labeling of anorectal drug products.

Code of Federal Regulations, 2011 CFR

2011-04-01

...., cream, lotion, or ointment).” (b) Indications. The labeling of the product states, under the heading... protective coating over inflamed tissues to help prevent drying of tissues.” (B) “Temporarily protects irritated areas.” (C) “Temporarily relieves burning.” (D) “Provides temporary relief from skin irritations...

The road to higher permanence and biodiversity in exurban wetlands.

PubMed

Urban, Mark C; Roehm, Robert

2018-01-01

Exurban areas are expanding throughout the world, yet their effects on local biodiversity remain poorly understood. Wetlands, in particular, face ongoing and substantial threats from exurban development. We predicted that exurbanization would reduce the diversity of wetland amphibian and invertebrate communities and that more spatially aggregated residential development would leave more undisturbed natural land, thereby promoting greater local diversity. Using structural equation models, we tested a series of predictions about the direct and indirect pathways by which exurbanization extent, spatial pattern, and wetland characteristics might affect diversity patterns in 38 wetlands recorded during a growing season. We used redundancy, indicator species, and nested community analyses to evaluate how exurbanization affected species composition. In contrast to expectations, we found higher diversity in exurban wetlands. We also found that housing aggregation did not significantly affect diversity. Exurbanization affected biodiversity indirectly by increasing roads and development, which promoted permanent wetlands with less canopy cover and more aquatic vegetation. These pond characteristics supported greater diversity. However, exurbanization was associated with fewer temporary wetlands and fewer of the species that depend on these habitats. Moreover, the best indicator species for an exurban wetland was the ram's head snail, a common disease vector in disturbed ponds. Overall, results suggest that exurbanization is homogenizing wetlands into more permanent water bodies. These more permanent, exurban ponds support higher overall animal diversity, but exclude temporary wetland specialists. Conserving the full assemblage of wetland species in expanding exurban regions throughout the world will require protecting and creating temporary wetlands.

Temporary placement of covered self-expandable metallic stents in the management of benign biliary strictures.

PubMed

Yasuda, Ichiro; Mukai, Tsuyoshi; Doi, Shinpei; Tomita, Eiichi; Moriwaki, Hisataka

2012-05-01

Currently, endoscopic intervention is widely attempted as the first-line treatment of benign biliary strictures because of its convenience and low morbidity. Plastic tube stents (PS) are usually used for such treatment; however, covered self-expandable metallic stents (C-SEMS) are becoming more commonly used at some institutions. The temporary placement of C-SEMS may lead to better outcomes because of their larger diameter and, therefore, better dilation of the stricture, especially in refractory cases. The aim of the present study was to evaluate the efficacy of the temporary placement of C-SEMS in the management of benign biliary strictures. We retrospectively reviewed our endoscopic retrograde cholangiopancreatography (ERCP) database (May 1996 to December 2010), and extracted the data of patients who underwent endoscopic treatment for benign biliary strictures. Then, the follow-up data from patient charts were reviewed to determine the long-term outcomes of those procedures. All patients (n = 56) initially had a PS placed, with or without balloon dilation. However, C-SEMS placement was later attempted in 12 patients because the stricture was refractory to placement of the PS. During their follow-up periods, two patients died of unrelated diseases after 15 and 17 months, and another two still had the C-SEMS in place after 9 and 50 months. In the remaining eight patients, the C-SEMS was removed after a median placement period of 6 months (range, 2-15). Seven patients in this group have not experienced a recurrence at a median follow-up time of 48 months. However, in one patient, stenosis did recur 8 months after the C-SEMS was removed. Temporary placement of C-SEMS can be a treatment option for benign biliary strictures, especially in refractory cases. © 2012 The Authors. Digestive Endoscopy © 2012 Japan Gastroenterological Endoscopy Society.

77 FR 14580 - Order Granting Temporary Exemption of Morningstar Credit Ratings, LLC From the Conflict of...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-12

.... Morningstar traditionally has operated mainly under the ``subscriber-paid'' business model, in which the NRSRO... Realpoint in the spring of 2010, Morningstar began to expand the scope of its business and initiated an... business, in the early stages of its expansion the fees associated with a single issuer-paid engagement...

26 CFR 1.170A-9T - Definition of section 170(b)(1)(A) organization (temporary).

Code of Federal Regulations, 2011 CFR

2011-04-01

... amount sufficient to enable it to commence its charitable activities and expand its solicitation program... materials, or an old age home which provides domiciliary or nursing services for members of the general... particular profession or field of special interest (taking into account the size of the area and the nature...

Tissue Expander Overfilling: Achieving New Dimensions of Customization in Breast Reconstruction.

PubMed

Treiser, Matthew D; Lahair, Tracy; Carty, Matthew J

2016-02-01

Overfill of tissue expanders is a commonly used modality to achieve customized dimensions in breast reconstruction. Little formal study of the dynamics of hyperexpansion of these devices has been performed to date, however. Overfill trials were performed using both Natrelle 133 MV and Mentor 8200 tissue expanders of indicated capacities ranging from 250 to 800 mL. Each expander was initially filled to its indicated capacity with normal water and then injected in regular increments to 400% overfill. Measurements of each expander's width, height, and projection were made at indicated capacity and with each successive incremental overfill injection, and these results were then recorded, collated, and analyzed. Over the first 50% overfill, all expanders demonstrated a logarithmic increase in projection (mean increase, 143 ± 9%) while maintaining essentially stable base dimensions. Overfill levels in excess of 50% were accompanied by linear increases in height, width, and projection, during which projection approached, but never equaled, base dimensions. Stress versus strain analyses demonstrated nonlinear biomechanical dynamics during the first 50% overfill, followed by standard elastic dynamics up to 400% overfill. At no point during the study, did expander tensions outstrip elastic properties, thereby explaining the lack of device rupture. Through overfilling, tunable geometries of tissue expanders can be accessed that may provide for increasing customization of reconstructions, particularly at overfill volumes up to 50% over indicated capacity. This study should serve to guide tissue expander selection and fill volumes that surgeons may implement in obtaining ideal reconstructed breast shapes.

Carbon Dioxide-Based versus Saline Tissue Expansion for Breast Reconstruction: Results of the XPAND Prospective, Randomized Clinical Trial.

PubMed

Ascherman, Jeffrey A; Zeidler, Kamakshi; Morrison, Kerry A; Appel, James Z; Berkowitz, R L; Castle, John; Colwell, Amy; Chun, Yoon; Johnson, Debra; Mohebali, Khashayar

2016-12-01

AeroForm is a new type of remote-controlled, needle-free, carbon dioxide-based expander involving a potentially faster method of tissue expansion. Results are presented here from the AirXpanders Patient Activated Controlled Tissue Expander pivotal trial comparing AeroForm to saline tissue expanders. Women undergoing two-stage breast reconstruction were randomized at 17 U.S. sites in this U.S. Food and Drug Administration-approved investigational device exemption trial. Expansion in the investigational arm was performed by the patient in 10-cc increments up to 30 cc/day of carbon dioxide and in the control arm by the physician with periodic bolus injections of saline. Safety endpoints, expansion and reconstruction times, pain, and satisfaction were assessed. One hundred fifty women were treated: 98 with carbon dioxide expanders (n = 168) and 52 with saline expanders (n = 88). The treatment success rate (all breasts exchanged successfully excluding non-device-related failures) was 96.1 percent for carbon dioxide and 98.8 percent for saline. Median time to full expansion and completion of the second-stage operation was 21.0 and 108.5 days (carbon dioxide) versus 46.0 and 136.5 days (saline), respectively, with a similar rate of overall complications. Ease of use for the carbon dioxide expander was rated high by patients (98 percent) and physicians (90 percent). The AirXpanders Patient Activated Controlled Tissue Expander trial results demonstrate that a carbon dioxide-based expander is an effective method of tissue expansion with a similar overall adverse event rate compared to saline expanders, and provides a more convenient and expedient expansion. Therapeutic, I.

Can microcarrier-expanded chondrocytes synthesize cartilaginous tissue in vitro?

PubMed

Surrao, Denver C; Khan, Aasma A; McGregor, Aaron J; Amsden, Brian G; Waldman, Stephen D

2011-08-01

Tissue engineering is a promising approach for articular cartilage repair; however, it is challenging to produce adequate amounts of tissue in vitro from the limited number of cells that can be extracted from an individual. Relatively few cell expansion methods exist without the problems of de-differentiation and/or loss of potency. Recently, however, several studies have noted the benefits of three-dimensional (3D) over monolayer expansion, but the ability of 3D expanded chondrocytes to synthesize cartilaginous tissue constructs has not been demonstrated. Thus, the purpose of this study was to compare the properties of engineered cartilage constructs from expanded cells (monolayer and 3D microcarriers) to those developed from primary chondrocytes. Isolated bovine chondrocytes were grown for 3 weeks in either monolayer (T-Flasks) or 3D microcarrier (Cytodex 3) expansion culture. Expanded and isolated primary cells were then seeded in high density culture on Millicell™ filters for 4 weeks to evaluate the ability to synthesize cartilaginous tissue. While microcarrier expansion was twice as effective as monolayer expansion (microcarrier: 110-fold increase, monolayer: 52-fold increase), the expanded cells (monolayer and 3D microcarrier) were not effectively able to synthesize cartilaginous tissue in vitro. Tissues developed from primary cells were substantially thicker and accumulated significantly more extracellular matrix (proteoglycan content: 156%-292% increase; collagen content: 70%-191% increase). These results were attributed to phenotypic changes experienced during the expansion phase. Monolayer expanded chondrocytes lost their native morphology within 1 week, whereas microcarrier-expanded cells were spreading by 3 weeks of expansion. While the use of 3D microcarriers can lead to large cellular yields, preservation of chondrogenic phenotype during expansion is required in order to synthesize cartilaginous tissue.

Wound ballistics 101: the mechanisms of soft tissue wounding by bullets.

PubMed

Stefanopoulos, P K; Pinialidis, D E; Hadjigeorgiou, G F; Filippakis, K N

2017-10-01

The mechanisms of soft tissue injury by bullets are reviewed, in the belief that the current incidence of firearm injuries in many urban areas necessitates an understanding of wound ballistics on the part of trauma surgeons who may not be familiar with the wounding factors involved. Review of the literature, with technical information obtained from appropriate non-medical texts. Despite numerous publications concerning the treatment of gunshot wounds, relatively few papers contain details on the mechanisms of ballistic trauma, with the main body of evidence derived from previous laboratory and animal studies which have only recently been systematically appraised. These studies have shown that in rifle injuries the main wound tract is surrounded by an area of damaged tissue as a result of the temporary cavitation induced once the bullet becomes destabilized or deformed. On the other hand, the more commonly encountered non-deforming handgun bullets cause damage limited to the bullet's path, mainly as a result of localized crush injury. The bullet's construction and ballistic behavior within tissue determine to what extent the previously overestimated velocity factor may influence wound severity. The damage produced from temporary cavitation depends on the tensile properties of the tissues involved, and in high-energy injuries may lead to progressive muscle tissue necrosis. Therefore, the term "high-energy" should be reserved for those injuries with substantial tissue damage extending beyond the visible wound tract.

Temporary placement of retrievable fully covered metallic stents versus percutaneous balloon dilation in the treatment of benign biliary strictures.

PubMed

Kim, Jin Hyoung; Gwon, Dong Il; Ko, Gi-Young; Sung, Kyu-Bo; Lee, Sung Koo; Yoon, Hyun-Ki; Shin, Ji Hoon; Song, Ho-Young

2011-06-01

To compare retrospectively percutaneous transhepatic primary placement of a retrievable self-expanding metallic stent with percutaneous balloon dilation for the treatment of benign biliary strictures. From 2005-2009, 66 patients with benign biliary strictures in whom an endoscopic approach failed or in whom such an approach was inaccessible were evaluated. Of 66 patients, 31 underwent balloon dilation, and 35 underwent temporary metallic stent placement. The etiologies of the benign strictures were anastomotic stricture after surgery (n = 54), stricture secondary to intraoperative injury (n = 9), inflammatory stricture (n = 2), and stricture secondary to trauma (n = 1). The primary patency rates were significantly better in the stent group (87% at 3 years) than in the balloon group (44% at 3 years; P = .022). The indwelling period of percutaneous transhepatic biliary drainage (PTBD) catheters after the initial procedure was able to be significantly reduced in the stent group (median 2.5 months) compared with the balloon group (median 4.5 months; P = .001). Significant bleeding (associated with PTBD) occurred in one patient in the balloon group. In the stent group, stent migration occurred in two patients, and one patient underwent surgery for stent removal after failure of removal under fluoroscopic guidance. Percutaneous primary placement of a retrievable self-expanding metallic stent showed superior intermediate-term results compared with percutaneous balloon dilation for the treatment of benign biliary strictures. In addition, the indwelling period of PTBD catheters can be significantly reduced using temporary stent placement. Copyright © 2011 SIR. Published by Elsevier Inc. All rights reserved.

Management of post-gastrectomy anastomosis site obstruction with a self-expandable metallic stent.

PubMed

Cha, Ra Ri; Lee, Sang Soo; Kim, Hyunjin; Kim, Hong Jun; Kim, Tae-Hyo; Jung, Woon Tae; Lee, Ok Jae; Bae, Kyung Soo; Jeong, Sang-Ho; Ha, Chang Yoon

2015-04-28

Post-gastrectomy anastomosis site obstruction is a relatively rare complication after a subtotal gastrectomy. We present a case of a 75-year-old man who underwent a truncal vagotomy, omental patch, gastrojejunostomy, and Braun anastomosis for duodenal ulcer perforation and a gastric outlet obstruction. Following the 10(th) postoperative day, the patient complained of abdominal discomfort and vomiting. We diagnosed post-gastrectomy anastomosis site obstruction by an upper gastrointestinal series and an upper endoscopic examination. We inserted a self-expandable metallic stent (SEMS) at the anastomosis site. The stent was fully expanded after deployment. On the day following the stent insertion, the patient began to eat, and his abdominal discomfort was resolved. This paper describes the successful management of post-gastrectomy anastomosis site obstruction with temporary placement of a SEMS.

77 FR 27022 - Certain Steel Threaded Rod From the People's Republic of China: Preliminary Results of the...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-08

... or coatings, such as plain oil finish as a temporary rust protectant, zinc coating (i.e., galvanized... (January 5, 2012). \\9\\ See, e.g., Certain Tissue Paper Products from the People's Republic of China... Certain Tissue Paper Products from the People's Republic of China: Final Results and Final Rescission, in...

Treatment of cuff-related tracheal stenosis with a fully covered retrievable expandable metallic stent.

PubMed

Chen, G; Wang, Z; Liang, X; Wang, Y; Wang, Y; Wang, Z; Xian, J

2013-04-01

To investigate the clinical effectiveness, complications, and optimal duration of use of covered retrievable expandable metallic stents in the management of cuff-related tracheal stenosis. Twenty-one patients with cuff-related tracheal stenosis, Meyer-Cotton grade II (29%) and III (71%), who underwent fluoroscopically guided placement of covered retrievable expandable metallic stents were studied. Sixty-four-section computed tomography (CT) and bronchovideoscopy were performed prior to stent insertion, 1 month after stent insertion, in the case of stent-related complications, and after stent removal. Clinical manifestations, Hugh-Jones classification, and forced expiratory volume in 1 s (FEV1) were used to evaluate respiratory function before and after stent insertion and removal. The diameter of the stricture and FEV1 changes before insertion and after removal were analysed using the paired samples t-test. A p-value of ≤0.05 was considered statistically significant. Twenty-one patients had 27 covered retrievable expandable metallic stents placed. Stents were electively removed from 20 patients. The median duration of stent placement was 5 months (range 4-12 months). One stent was not removed due to mucopolysaccharidosis type II (MPS II or Hunter syndrome) with tracheomalacia. After stent removal, airway dimensions increased and airway occlusion was symptomatically relieved in all patients. CT and bronchovideoscopy showed patent lumens with increased dimensions. Stent-related complications occurred in 19 (91%) patients, including granulation tissue formation (n = 18, 86%), stent migration and stent expectoration (n = 2, 10%), mucus plugging (n = 1, 5%), and halitosis (n = 6, 29%). Some patients experienced multiple complications, which were all managed effectively while the stent was still in place. There was a statistically significant difference in the diameter of the stricture and FEV1 between the time of stent insertion and removal. An improvement in Hugh-Jones classification of greater than one grade was seen in patients after stent removal. Temporary placement of a fully covered retrievable expandable metallic stent is safe and effective in cuff-related tracheal stenosis. The optimal duration of stent placement may be 4-8 months. Copyright © 2012 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

In vitro assessment of MRI issues at 3-Tesla for a breast tissue expander with a remote port.

PubMed

Linnemeyer, Hannah; Shellock, Frank G; Ahn, Christina Y

2014-04-01

A patient with a breast tissue expander may require a diagnostic assessment using magnetic resonance imaging (MRI). To ensure patient safety, this type of implant must undergo in vitro MRI testing using proper techniques. Therefore, this investigation evaluated MRI issues (i.e., magnetic field interactions, heating, and artifacts) at 3-Tesla for a breast tissue expander with a remote port. A breast tissue expander with a remote port (Integra Breast Tissue Expander, Model 3612-06 with Standard Remote Port, PMT Corporation, Chanhassen, MN) underwent evaluation for magnetic field interactions (translational attraction and torque), MRI-related heating, and artifacts using standardized techniques. Heating was evaluated by placing the implant in a gelled-saline-filled phantom and MRI was performed using a transmit/receive RF body coil at an MR system reported, whole body averaged specific absorption rate of 2.9-W/kg. Artifacts were characterized using T1-weighted and GRE pulse sequences. Magnetic field interactions were not substantial and, thus, will not pose a hazard to a patient in a 3-Tesla or less MRI environment. The highest temperature rise was 1.7°C, which is physiologically inconsequential. Artifacts were large in relation to the remote port and metal connector of the implant but will only present problems if the MR imaging area of interest is where these components are located. A patient with this breast tissue expander with a remote port may safely undergo MRI at 3-Tesla or less under the conditions used for this investigation. These findings are the first reported at 3-Tesla for a tissue expander. Copyright © 2014 Elsevier Inc. All rights reserved.

Temporary Arterial Embolization of Liver Parenchyma with Degradable Starch Microspheres (EmboCept{sup ®}S) in a Swine Model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pieper, Claus C., E-mail: claus.christian.pieper@ukb.uni-bonn.de; Meyer, Carsten, E-mail: Carsten.Meyer@ukb.uni-bonn.de; Vollmar, Brigitte, E-mail: brigitte.vollmar@med.uni-rostock.de

BackgroundThis study aimed to evaluate the embolic properties, time to reperfusion, and histologic changes in temporary embolization of liver tissue with degradable starch microspheres (DSM) in a swine model.MethodsIn four adult minipigs, DSMs were injected into the right or left hepatic artery on the lobar level until complete stasis of the blood flow was detectable angiographically. The time required to complete angiographically determined reperfusion was noted. The animals were killed 3 h after complete reperfusion, and samples were taken from the liver. Histologic examinations of the embolized liver parenchyma and untreated tissue were performed.ResultsHepatic arterial embolization using DSMs was technically successfulmore » in all cases, with complete blood flow stasis shown by control angiography. A single vial of DSMs (450 mg/7.5 ml) was sufficient to embolize a whole liver lobe in all cases. Angiography showed complete reconstitution of hepatic arterial perfusion after a mean time to reperfusion of 32 ± 6.1 min (range, 26–39 min). Hematoxylin and eosin staining showed no histologically detectable differences between untreated tissue and parenchyma embolized with DSMs except for mild sinusoidal congestion in one case. Indirect in situ DNA nick end labeling staining (TUNEL) showed only single positive hepatocytes, indicating apoptosis.ConclusionTemporary embolization of the hepatic artery using DSMs is feasible with complete reperfusion after 30 min in pigs. Even after complete arterial blood flow stasis, no extensive tissue damage to the embolized liver parenchyma was observed at histologic examinations in this short-term study.« less

Guided bone generation in a rabbit mandible model after periosteal expansion with an osmotic tissue expander.

PubMed

Abrahamsson, Peter; Isaksson, Sten; Andersson, Gunilla

2011-11-01

To evaluate the space-maintaining capacity of titanium mesh covered by a collagen membrane after soft tissue expansion on the lateral border of the mandible in rabbits, and to assess bone quantity and quality using autogenous particulate bone or bone-substitute (Bio-Oss(®) ), and if soft tissue ingrowth can be avoided by covering the mesh with a collagen membrane. In 11 rabbits, a self-inflatable soft tissue expander was placed under the lateral mandibular periosteum via an extra-oral approach. After 2 weeks, the expanders were removed and a particulated onlay bone graft and deproteinized bovine bone mineral (DBBM) (Bio-Oss(®) ) were placed in the expanded area and covered by a titanium mesh. The bone and DBBM were separated in two compartments under the mesh with a collagen membrane in between. The mesh was then covered with a collagen membrane. After 3 months, the animals were sacrificed and specimens were collected for histology. The osmotic soft tissue expander created a subperiosteal pocket and a ridge of new bone formed at the edges of the expanded periosteum in all sites. After the healing period of 3 months, no soft tissue dehiscence was recorded. The mean bone fill was 58.1±18% in the bone grafted area and 56.9±13.7% in the DBBM area. There was no significant difference between the autologous bone graft and the DDBM under the titanium mesh with regard to the total bone area or the mineralized bone area. Scanning electron microscopy showed that new bone was growing in direct contact with the DBBM particles and the titanium mesh. There is a soft tissue ingrowth even after soft tissue expansion and protection of the titanium mesh with a collagen membrane. This study confirms that an osmotic soft tissue expander creates a surplus of periosteum and soft tissue, and that new bone can subsequently be generated under a titanium mesh with the use of an autologous bone graft or DBBM. © 2011 John Wiley & Sons A/S.

Porous expandable device for attachment to bone tissue

DOEpatents

Rybicki, Edmund F.; Wheeler, Kenneth Ray; Hulbert, Lewis E.; Karagianes, Manuel Tom; Hassler, Craig R.

1977-01-01

A device for attaching to substantially solid living bone tissue, comprising a body member having an outer surface shaped to fit approximately into an empty space in the tissue and having pores into which the tissue can grow to strengthen the bond between the device and the tissue, and adjustable means for expanding the body member against the tissue to an extent such as to provide a compressive stress capable of maintaining a snug and stable fit and of enhancing the growth of the tissue into the pores in the body member. The expanding means is adjustable to provide a stress between the tissue and the body member in the range of about 150 to 750 psi, typically 150 to 350 psi. Typically the body member comprises an expandable cylindrical portion having at least one radial slit extending longitudinally from a first end to the vicinity of the opposite (second) end thereof, at least one radial slit extending longitudinally from the second end to the vicinity of the first end thereof, and a tapered cylindrical hole extending coaxially from a wider circular opening in the first end to a narrower circular opening communicating with the second end.

Radiation Therapy (For Parents)

MedlinePlus

... temporary, it can be permanent. Sore Mouth and Tooth Decay The tissues of the mouth may be sore ... and there may be an increased risk of tooth decay if a child received radiation therapy to the ...

Microbial responses to changes in flow status in temporary headwater streams: a cross-system comparison

PubMed Central

Febria, Catherine M.; Hosen, Jacob D.; Crump, Byron C.; Palmer, Margaret A.; Williams, D. Dudley

2015-01-01

Microbial communities are responsible for the bulk of biogeochemical processing in temporary headwater streams, yet there is still relatively little known about how community structure and function respond to periodic drying. Moreover, the ability to sample temporary habitats can be a logistical challenge due to the limited capability to measure and predict the timing, intensity and frequency of wet-dry events. Unsurprisingly, published datasets on microbial community structure and function are limited in scope and temporal resolution and vary widely in the molecular methods applied. We compared environmental and microbial community datasets for permanent and temporary tributaries of two different North American headwater stream systems: Speed River (Ontario, Canada) and Parkers Creek (Maryland, USA). We explored whether taxonomic diversity and community composition were altered as a result of flow permanence and compared community composition amongst streams using different 16S microbial community methods (i.e., T-RFLP and Illumina MiSeq). Contrary to our hypotheses, and irrespective of method, community composition did not respond strongly to drying. In both systems, community composition was related to site rather than drying condition. Additional network analysis on the Parkers Creek dataset indicated a shift in the central microbial relationships between temporary and permanent streams. In the permanent stream at Parkers Creek, associations of methanotrophic taxa were most dominant, whereas associations with taxa from the order Nitrospirales were more dominant in the temporary stream, particularly during dry conditions. We compared these results with existing published studies from around the world and found a wide range in community responses to drying. We conclude by proposing three hypotheses that may address contradictory results and, when tested across systems, may expand understanding of the responses of microbial communities in temporary streams to natural and human-induced fluctuations in flow-status and permanence. PMID:26089816

Biologically active chitosan systems for tissue engineering and regenerative medicine.

PubMed

Jiang, Tao; Kumbar, Sangamesh G; Nair, Lakshmi S; Laurencin, Cato T

2008-01-01

Biodegradable polymeric scaffolds are widely used as a temporary extracellular matrix in tissue engineering and regenerative medicine. By physical adsorption of biomolecules on scaffold surface, physical entrapment of biomolecules in polymer microspheres or hydrogels, and chemical immobilization of oligopeptides or proteins on biomaterials, biologically active biomaterials and scaffolds can be derived. These bioactive systems show great potential in tissue engineering in rendering bioactivity and/or specificity to scaffolds. This review highlights some of the biologically active chitosan systems for tissue engineering application and the associated strategies to develop such bioactive chitosan systems.

Tissue Expander Overfilling: Achieving New Dimensions of Customization in Breast Reconstruction

PubMed Central

Treiser, Matthew D.; Lahair, Tracy

2016-01-01

Introduction: Overfill of tissue expanders is a commonly used modality to achieve customized dimensions in breast reconstruction. Little formal study of the dynamics of hyperexpansion of these devices has been performed to date, however. Methods: Overfill trials were performed using both Natrelle 133 MV and Mentor 8200 tissue expanders of indicated capacities ranging from 250 to 800 mL. Each expander was initially filled to its indicated capacity with normal water and then injected in regular increments to 400% overfill. Measurements of each expander’s width, height, and projection were made at indicated capacity and with each successive incremental overfill injection, and these results were then recorded, collated, and analyzed. Results: Over the first 50% overfill, all expanders demonstrated a logarithmic increase in projection (mean increase, 143 ± 9%) while maintaining essentially stable base dimensions. Overfill levels in excess of 50% were accompanied by linear increases in height, width, and projection, during which projection approached, but never equaled, base dimensions. Stress versus strain analyses demonstrated nonlinear biomechanical dynamics during the first 50% overfill, followed by standard elastic dynamics up to 400% overfill. At no point during the study, did expander tensions outstrip elastic properties, thereby explaining the lack of device rupture. Conclusions: Through overfilling, tunable geometries of tissue expanders can be accessed that may provide for increasing customization of reconstructions, particularly at overfill volumes up to 50% over indicated capacity. This study should serve to guide tissue expander selection and fill volumes that surgeons may implement in obtaining ideal reconstructed breast shapes. PMID:27014541

Mucosal Perfusion Preservation by a Novel Shapeable Tissue Expander for Oral Reconstruction

PubMed Central

Barwinska, Daria; Garner, John; Davidson, Darrell D.; Cook, Todd G.; Eckert, George J.; Tholpady, Sunil S.; March, Keith L.; Park, Kinam

2017-01-01

Background: There are few methods for expanding oral mucosa, and these often cause complications such as tissue necrosis and expander eruption. This study examines mucosal blood perfusion following insertion of a novel shapeable hydrogel tissue expander (HTE). The canine model used subgingival insertion of HTE following tooth extraction and alveolar bone reduction. The primary goal of this study was to gain understanding of epithelial perfusion and reparative responses of gingival mucosa during HTE expansion. Methods: Nine Beagle dogs underwent bilateral premolar maxillary and mandibular tooth extraction. Three to four months later, HTE-contoured inserts were implanted submucosally under the buccal surface of the alveolar ridge. After removal and following a 6- to 7-month period of healing, new HTE implants were inserted at the same sites. The area was assessed weekly for tissue perfusion and volume of expansion. Biopsies for histological analysis were performed at the time of expander removal. Results: Within 2 weeks following the second insertion, blood flow returned to baseline (defined as the values of perfusion measurements at the presurgery assessment) and remained normal until hydrogel full expansion and removal. Volume expansion analysis revealed that the hydrogel doubled in volume. Histological assessment showed no macrophage or inflammatory infiltration of the mucosa. No superficial fibrosis, decreased vascularity, or mucosal change was seen. Conclusion: Maintenance of adequate tissue perfusion is a clinically important aspect of tissue expander performance to reduce risk of device loss or injury to the patient, particularly for areas with a history of previous surgeries. PMID:28894668

Toolbox No. 2: Expanding the Role of Foster Parents in Achieving Permanency. Toolboxes for Permanency.

ERIC Educational Resources Information Center

Dougherty, Susan

Noting that over the last decade, the role of a foster parent has evolved from temporary caregiver to essential part of a professional team in determining the best long-term plan for children in their care, this guide focuses on practical ways in which best child welfare practice can be incorporated into the recruitment, training, and support of…

Corneal Tissue Engineering: Recent Advances and Future Perspectives

PubMed Central

Ghezzi, Chiara E.; Rnjak-Kovacina, Jelena

2015-01-01

To address the growing need for corneal transplants two main approaches are being pursued: allogenic and synthetic materials. Allogenic tissue from human donors is currently the preferred choice; however, there is a worldwide shortage in donated corneal tissue. In addition, tissue rejection often limits the long-term success of this approach. Alternatively, synthetic homologs to donor corneal grafts are primarily considered temporary replacements until suitable donor tissue becomes available, as they result in a high incidence of graft failure. Tissue engineered cornea analogs would provide effective cornea tissue substitutes and alternatives to address the need to reduce animal testing of commercial products. Recent progress toward these needs is reviewed here, along with future perspectives. PMID:25434371

Combination therapy with intra-articular injection of mesenchymal stem cells and articulated joint distraction for repair of a chronic osteochondral defect in the rabbit.

PubMed

Harada, Yohei; Nakasa, Tomoyuki; Mahmoud, Elhussein Elbadry; Kamei, Goki; Adachi, Nobuo; Deie, Masataka; Ochi, Mitsuo

2015-10-01

The present study investigated intra-articular injection of bone-marrow-derived mesenchymal stem cells (MSCs) combined with articulated joint distraction as treatment for osteochondral defects. Large osteochondral defects were created in the weight-bearing area of the medial femoral condyle in rabbit knees. Four weeks after defect creation, rabbits were divided into six groups: control group, MSC group, distraction group, distraction + MSC group, temporary distraction group, and temporary distraction + MSC group. Groups with MSC received intra-articular injection of MSCs. Groups with distraction underwent articulated distraction arthroplasty. Groups with temporary distraction discontinued the distraction after 4 weeks. The rabbits were euthanized at 4, 8, and 12 weeks after treatment except temporary distraction groups which were euthanized at only 12 weeks. Histological scores in the distraction + MSC group were significantly better than in the control, MSC group or distraction group at 4 and 8 weeks, but showed no further improvement. At 12 weeks, the temporary distraction + MSC group showed the best results, demonstrating hyaline cartilage repair with regeneration of the osteochondral junction. In conclusion, joint distraction with intra-articular injection of MSCs promotes early cartilage repair, and compressive loading of the repair tissue after temporary distraction stimulates articular cartilage regeneration. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Extracellular matrix proteins as temporary coating for thin-film neural implants

NASA Astrophysics Data System (ADS)

Ceyssens, Frederik; Deprez, Marjolijn; Turner, Neill; Kil, Dries; van Kuyck, Kris; Welkenhuysen, Marleen; Nuttin, Bart; Badylak, Stephen; Puers, Robert

2017-02-01

Objective. This study investigates the suitability of a thin sheet of extracellular matrix (ECM) proteins as a resorbable coating for temporarily reinforcing fragile or ultra-low stiffness thin-film neural implants to be placed on the brain, i.e. microelectrocorticographic (µECOG) implants. Approach. Thin-film polyimide-based electrode arrays were fabricated using lithographic methods. ECM was harvested from porcine tissue by a decellularization method and coated around the arrays. Mechanical tests and an in vivo experiment on rats were conducted, followed by a histological tissue study combined with a statistical equivalence test (confidence interval approach, 0.05 significance level) to compare the test group with an uncoated control group. Main results. After 3 months, no significant damage was found based on GFAP and NeuN staining of the relevant brain areas. Significance. The study shows that ECM sheets are a suitable temporary coating for thin µECOG neural implants.

Tanshinon IIA injection accelerates tissue expansion by reducing the formation of the fibrous capsule.

PubMed

Yu, Qingxiong; Sheng, Lingling; Yang, Mei; Zhu, Ming; Huang, Xiaolu; Li, Qingfeng

2014-01-01

The tissue expansion technique has been applied to obtain new skin tissue to repair large defects in clinical practice. The implantation of tissue expander could initiate a host response to foreign body (FBR), which leads to fibrotic encapsulation around the expander and prolongs the period of tissue expansion. Tanshinon IIA (Tan IIA) has been shown to have anti-inflammation and immunoregulation effect. The rat tissue expansion model was used in this study to observe whether Tan IIA injection systematically could inhibit the FBR to reduce fibrous capsule formation and accelerate the process of tissue expansion. Forty-eight rats were randomly divided into the Tan IIA group and control group with 24 rats in each group. The expansion was conducted twice a week to maintain a capsule pressure of 60 mmHg. The expansion volume and expanded area were measured. The expanded tissue in the two groups was harvested, and histological staining was performed; proinflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β) and transforming growth factor-β (TGF-β) were examined. The expansion volume and the expanded area in the Tan IIA group were greater than that of the control group. The thickness of the fibrous capsule in the Tan IIA group was reduced with no influence on the normal skin regeneration. Decreased infiltration of macrophages, lower level of TNF-α, IL-6, IL-1β and TGF-β, less proliferating myofibroblasts and enhanced neovascularization were observed in the Tan IIA group. Our findings indicated that the Tan IIA injection reduced the formation of the fibrous capsule and accelerated the process of tissue expansion by inhibiting the FBR.

Repair of Craniomaxillofacial Traumatic Soft Tissue Defects With Tissue Expansion in the Early Stage.

PubMed

Han, Yan; Zhao, Jianhui; Tao, Ran; Guo, Lingli; Yang, Hongyan; Zeng, Wei; Song, Baoqiang; Xia, Wensen

2017-09-01

Craniomaxillofacial traumatic soft tissue defects severely affect the function and appearance of the patients. The traditional skin grafting or free flap transplantation can only close the defects in the early stage of operation but cannot ensure similar color, texture, and relative aesthetic contour. In the present study, the authors have explored a novel strategy to repair craniomaxillofacial traumatic soft tissue defects by tissue expansion in the early stage and have obtained satisfactory results. Eighteen patients suffering large craniomaxillofacial traumatic soft tissue defects were treated by thorough debridement leaving the wounds unclosed or simply closed with thin split-thickness scalp grafts, adjacent expander implantation in the first stage, and expanded flap transposition in the second stage. There were 11 male patients and 7 female patients ranging in age from 3.5 to 40 years (mean, 19.4 ± 12.2 years), with average 15 months follow-up (range, 3-67 months). The average expansion time was 74.3 days (range, 53-96 days). The 18 patients with a total of 22 expanders were treated with satisfactory results. All the flaps survived and the skin color, texture, and contour well matched those of the peripheral tissue. Only 1 complication of infection happened in the 18 cases (5.56%) and the 22 expanders (4.55%), which was similar to the rate reported in the literature. No other complications related to the expanders occurred. Debridement and tissue expansion in the early stage has been proved to be a more effective strategy to repair craniomaxillofacial traumatic soft tissue defects. This strategy can not only achieve satisfactory color, unbulky and well-matched texture similar to normal, but also avoid unnecessary donor site injuries.

Evaluation of Soft Tissue Coverage over Porous Polymethylmethacrylate Space Maintainers Within Nonhealing Alveolar Bone Defects

PubMed Central

Kretlow, James D.; Shi, Meng; Young, Simon; Spicer, Patrick P.; Demian, Nagi; Jansen, John A.; Wong, Mark E.; Kasper, F. Kurtis

2010-01-01

Current treatment of traumatic craniofacial injuries often involves early free tissue transfer, even if the recipient site is contaminated or lacks soft tissue coverage. There are no current tissue engineering strategies to definitively regenerate tissues in such an environment at an early time point. For a tissue engineering approach to be employed in the treatment of such injuries, a two-stage approach could potentially be used. The present study describes methods for fabrication, characterization, and processing of porous polymethylmethacrylate (PMMA) space maintainers for temporary retention of space in bony craniofacial defects. Carboxymethylcellulose hydrogels were used as a porogen. Implants with controlled porosity and pore interconnectivity were fabricated by varying the ratio of hydrogel:polymer and the amount of carboxymethylcellulose within the hydrogel. The in vivo tissue response to the implants was observed by implanting solid, low-porosity, and high-porosity implants (n = 6) within a nonhealing rabbit mandibular defect that included an oral mucosal defect to allow open communication between the oral cavity and the mandibular defect. Oral mucosal wound healing was observed after 12 weeks and was complete in 3/6 defects filled with solid PMMA implants and 5/6 defects filled with either a low- or high-porosity PMMA implant. The tissue response around and within the pores of the two formulations of porous implants tested in vivo was characterized, with the low-porosity implants surrounded by a minimal but well-formed fibrous capsule in contrast to the high-porosity implants, which were surrounded and invaded by almost exclusively inflammatory tissue. On the basis of these results, PMMA implants with limited porosity hold promise for temporary implantation and space maintenance within clean/contaminated bone defects. PMID:20524844

Breast reconstruction with tissue expanders: implementation of a standardized best-practices protocol to reduce infection rates.

PubMed

Khansa, Ibrahim; Hendrick, Russell G; Shore, Alison; Meyerson, Joseph; Yang, Maelee; Boehmler, James H

2014-07-01

Periprosthetic infection remains a frustrating and costly complication of breast reconstruction with tissue expanders. Although some specific steps have been previously shown to reduce periprosthetic infections, no comprehensive protocol addressing all aspects of preoperative, intraoperative, and postoperative patient management has been evaluated in the literature. The authors' goal was to evaluate the effectiveness of their protocol at reducing periprosthetic infections. A comprehensive, best-practices protocol was introduced and implemented in November of 2010. All patients undergoing breast reconstruction using tissue expanders at the authors' institution in the 5 years before the protocol, and in the 2 years after, were analyzed. Three hundred five patients underwent 456 tissue expander reconstructions in the 5 years before the protocol, and 198 patients underwent 313 reconstructions in the 2 years after. Significantly fewer patients developed periprosthetic infection after protocol (11.6 percent versus 18.4 percent; p=0.042), and the number of infected tissue expanders trended toward a decrease (9.3 percent versus 13.2 percent; p=0.097). On multivariate analysis, the protocol significantly reduced the odds of periprosthetic infection (OR, 0.45; p=0.022). Predictors of infection included obesity (OR, 2.01; p=0.045) and preoperative breast size larger than C cup (OR, 2.83; p=0.006). The authors' comprehensive, best-practices protocol allowed them to reduce the odds of tissue expander infections by 55 percent (OR, 0.45; p=0.022). The authors were able to identify several potential areas of improvement that may help them lower the rate of infection further in the future. Therapeutic, III.

A Randomized Controlled Trial Comparing Endoscopic-Assisted Versus Open Neck Tissue Expander Placement in Reconstruction of Post-Burn Facial Scar Deformities.

PubMed

As'adi, Kamran; Emami, Seyed Abolhassan; Salehi, Seyed Hamid; Shoar, Saeed

2016-08-01

Tissue expansion has evolved reconstruction surgery by providing a great source of additional tissue for large skin defects. Nevertheless, wide application of tissue expander reconstruction is challenging due to high complication rates and uncertainty about final outcomes. Recently, endoscopy has shown promise in reconstructive surgeries using tissue expander placement. This study aimed to compare outcomes between open and endoscopic-assisted neck tissue expander placement in reconstruction of post-burn facial scar deformities. Through a randomized clinical trial, 63 patients with facial burn scars were assigned to an open group or endoscopic group for placement of 81 tissue expanders. The complication rate, operative time, length of hospital stay, and time to full expansion were compared between the two groups. Thirty-one patients were assigned to the open group and 32 patients to the endoscopic group. The average operative time was significantly reduced in the endoscopic group compared with the open group (42.2 ± 3.6, 56.5 ± 4.5 min, p < 0.05). The complication rate was significantly lower in the endoscopic group than the open group (6 vs. 16, p < 0.05). Hospital stay was also significantly diminished from 26.3 ± 7.7 h in open group to 7.4 ± 4.5 h in endoscopic group (p < 0.0001). There was a significant reduction in time to full expansion in the endoscopic group as compared with the open group (93.5 ± 10.2 vs. 112.1 ± 14.2 days, p = 0.002). Endoscopic neck tissue expander placement significantly reduced operative time, the postoperative complication rate, length of hospital stay, and time to achieve full expansion and allowed early initiation of expansion and remote placement of the port in relation to the expander pocket. 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 www.springer.com/00266 .

Update: Temporary Total Depletion of U.S. Licensed Yellow Fever Vaccine for Civilian Travelers Addressed by Investigational New Drug Use of Imported Stamaril Vaccine.

PubMed

Gershman, Mark D; Sotir, Mark J

2017-07-28

Sanofi Pasteur, the manufacturer of the only yellow fever vaccine (YF-VAX) licensed in the United States, has announced that their stock of YF-VAX is totally depleted as of July 24, 2017. YF-VAX for civilian use will be unavailable for ordering from Sanofi Pasteur until mid-2018, when their new manufacturing facility is expected to be completed. However, YF-VAX might be available at some clinics for several months, until remaining supplies at those sites are exhausted. In anticipation of this temporary total depletion, in 2016, Sanofi Pasteur submitted an expanded access investigational new drug application to the Food and Drug Administration to allow for importation and use of Stamaril. The Food and Drug Administration accepted Sanofi Pasteur's application in October 2016.

Streamlined bioreactor-based production of human cartilage tissues.

PubMed

Tonnarelli, B; Santoro, R; Adelaide Asnaghi, M; Wendt, D

2016-05-27

Engineered tissue grafts have been manufactured using methods based predominantly on traditional labour-intensive manual benchtop techniques. These methods impart significant regulatory and economic challenges, hindering the successful translation of engineered tissue products to the clinic. Alternatively, bioreactor-based production systems have the potential to overcome such limitations. In this work, we present an innovative manufacturing approach to engineer cartilage tissue within a single bioreactor system, starting from freshly isolated human primary chondrocytes, through the generation of cartilaginous tissue grafts. The limited number of primary chondrocytes that can be isolated from a small clinically-sized cartilage biopsy could be seeded and extensively expanded directly within a 3D scaffold in our perfusion bioreactor (5.4 ± 0.9 doublings in 2 weeks), bypassing conventional 2D expansion in flasks. Chondrocytes expanded in 3D scaffolds better maintained a chondrogenic phenotype than chondrocytes expanded on plastic flasks (collagen type II mRNA, 18-fold; Sox-9, 11-fold). After this "3D expansion" phase, bioreactor culture conditions were changed to subsequently support chondrogenic differentiation for two weeks. Engineered tissues based on 3D-expanded chondrocytes were more cartilaginous than tissues generated from chondrocytes previously expanded in flasks. We then demonstrated that this streamlined bioreactor-based process could be adapted to effectively generate up-scaled cartilage grafts in a size with clinical relevance (50 mm diameter). Streamlined and robust tissue engineering processes, as the one described here, may be key for the future manufacturing of grafts for clinical applications, as they facilitate the establishment of compact and closed bioreactor-based production systems, with minimal automation requirements, lower operating costs, and increased compliance to regulatory guidelines.

Human endothelial colony-forming cells expanded with an improved protocol are a useful endothelial cell source for scaffold-based tissue engineering.

PubMed

Denecke, Bernd; Horsch, Liska D; Radtke, Stefan; Fischer, Johannes C; Horn, Peter A; Giebel, Bernd

2015-11-01

One of the major challenges in tissue engineering is to supply larger three-dimensional (3D) bioengineered tissue transplants with sufficient amounts of nutrients and oxygen and to allow metabolite removal. Consequently, artificial vascularization strategies of such transplants are desired. One strategy focuses on endothelial cells capable of initiating new vessel formation, which are settled on scaffolds commonly used in tissue engineering. A bottleneck in this strategy is to obtain sufficient amounts of endothelial cells, as they can be harvested only in small quantities directly from human tissues. Thus, protocols are required to expand appropriate cells in sufficient amounts without interfering with their capability to settle on scaffold materials and to initiate vessel formation. Here, we analysed whether umbilical cord blood (CB)-derived endothelial colony-forming cells (ECFCs) fulfil these requirements. In a first set of experiments, we showed that marginally expanded ECFCs settle and survive on different scaffold biomaterials. Next, we improved ECFC culture conditions and developed a protocol for ECFC expansion compatible with 'Good Manufacturing Practice' (GMP) standards. We replaced animal sera with human platelet lysates and used a novel type of tissue-culture ware. ECFCs cultured under the new conditions revealed significantly lower apoptosis and increased proliferation rates. Simultaneously, their viability was increased. Since extensively expanded ECFCs could still settle on scaffold biomaterials and were able to form tubular structures in Matrigel assays, we conclude that these ex vivo-expanded ECFCs are a novel, very potent cell source for scaffold-based tissue engineering. Copyright © 2013 John Wiley & Sons, Ltd.

A low cost strategy to monitor the expansion and contraction of the flowing stream network in mountainous headwater catchments

NASA Astrophysics Data System (ADS)

Assendelft, Rick; van Meerveld, Ilja; Seibert, Jan

2017-04-01

Streams are dynamic features in the landscape. The flowing stream network expands and contracts, connects and disconnects in response to rainfall events and seasonal changes in catchment wetness. Sections of the river system that experience these wet and dry cycles are often referred to as temporary streams. Temporary streams are abundant and widely distributed freshwater ecosystems. They account for more than half of the total length of the global stream network, are unique habitats and form important hydrological and ecological links between the uplands and perennial streams. However, temporary streams have been largely unstudied, especially in mountainous headwater catchments. The dynamic character of these systems makes it difficult to monitor them. We describe a low-cost, do-it-yourself strategy to monitor the occurrence of water and flow in temporary streams. We evaluate this strategy in two headwater catchments in Switzerland. The low cost sensor network consists of electrical resistivity sensors, water level switches, temperature sensors and flow sensors. These sensors are connected to Arduino microcontrollers and data loggers, which log the data every 5 minutes. The data from the measurement network are compared with observations (mapping of the temporary stream network) as well as time lapse camera data to evaluate the performance of the sensors. We look at how frequently the output of the sensors (presence and absence of water from the ER and water level data, and flow or no-flow from the flow sensors) corresponds to the observed channel state. This is done for each sensor, per sub-catchment, per precipitation event and per sensor location to determine the best sensor combination to monitor temporary streams in mountainous catchments and in which situation which sensor combination works best. The preliminary results show that the sensors and monitoring network work well. The data from the sensors corresponds with the observations and provides information on the expansion of the stream network pattern.

Hepatic venous outflow obstruction after living donor liver transplantation managed with ectopic placement of a foley catheter: A case report

PubMed Central

Wahab, Mohamed Abdel; Shehta, Ahmed; Hamed, Hosam; Elshobary, Mohamed; Salah, Tarek; Sultan, Ahmed Mohamed; Fathy, Omar; Elghawalby, Ahmed; Yassen, Amr; Shiha, Usama

2015-01-01

Introduction The early hepatic venous outflow obstruction (HVOO) is a rare but serious complication after liver transplantation, which may result in graft loss. We report a case of early HVOO after living donor liver transplantation, which was managed by ectopic placement of foley catheter. Presentation A 51 years old male patient with end stage liver disease received a right hemi-liver graft. On the first postoperative day the patient developed impairment of the liver functions. Doppler ultrasound (US) showed absence of blood flow in the right hepatic vein without thrombosis. The decision was to re-explore the patient, which showed torsion of the graft upward and to the right side causing HVOO. This was managed by ectopic placement of a foley catheter between the graft and the diaphragm and the chest wall. Gradual deflation of the catheter was gradually done guided by Doppler US and the patient was discharged without complications. Discussion Mechanical HVOO results from kinking or twisting of the venous anastomosis due to anatomical mismatch between the graft and the recipient abdomen. It should be managed surgically by repositioning of the graft or redo of venous anastomosis. Several ideas had been suggested for repositioning and fixation of the graft by the use of Sengstaken–Blakemore tubes, tissue expanders, and surgical glove expander. Conclusion We report the use of foley catheter to temporary fix the graft and correct the HVOO. It is a simple and safe way, and could be easily monitored and removed under Doppler US without any complications. PMID:25805611

78 FR 57685 - Guidance Regarding Deduction and Capitalization of Expenditures Related to Tangible Property

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-19

...This document contains final regulations that provide guidance on the application of sections 162(a) and 263(a) of the Internal Revenue Code (Code) to amounts paid to acquire, produce, or improve tangible property. The final regulations clarify and expand the standards in the current regulations under sections 162(a) and 263(a). These final regulations replace and remove temporary regulations under sections 162(a) and 263(a) and withdraw proposed regulations that cross referenced the text of those temporary regulations. This document also contains final regulations under section 167 regarding accounting for and retirement of depreciable property and final regulations under section 168 regarding accounting for property under the Modified Accelerated Cost Recovery System (MACRS) other than general asset accounts. The final regulations will affect all taxpayers that acquire, produce, or improve tangible property. These final regulations do not finalize or remove the 2011 temporary regulations under section 168 regarding general asset accounts and disposition of property subject to section 168, which are addressed in the notice of proposed rulemaking on this subject in the Proposed Rules section in this issue of the Federal Register.

Propagation method of saving valuable strains from a Mycobacterium liflandii infection in Western clawed frogs (Silurana tropicalis).

PubMed

Chai, Norin; Bronchain, Odile; Panteix, Gilles; Godreuil, Sylvain; de Medeiros, Christophe; Saunders, Richard; Bouts, Tim; de Luze, Amaury

2012-03-01

Mycobacterium liflandii has been responsible for an emerging infection reported in the international trade of Western clawed frogs (Silurana tropicalis). This study shows that this mycolactone-producing Mycobacterium (MPM) has expanded its distribution range to France. The results of this study suggest that the use of in vitro fertilization to maintain genetic lines could be a temporary solution for valuable S. tropicalis propagation.

Chronic expanding hematoma in the retroperitoneal space: a case report

PubMed Central

2013-01-01

Background Chronic expanding hematoma is a rare condition that develops after surgery, trauma, or injury. It can also develop at any location in the body in the absence of trauma. Clinical findings and various diagnostic imaging modalities can aid in the differential diagnosis of this condition. In general, hematomas are naturally reabsorbed and rarely cause serious problems. However, hematomas that develop slowly without a history of trauma, surgery, or bleeding disorders could be difficult to differentiate from soft tissue neoplasms. In the present case, we describe a patient, without any history or physical evidence of trauma, who exhibited a large chronic expanding hematoma in the retroperitoneal space that resulted in hydronephrosis because of the pressure exerted on the left ureter. Case presentation A 69-year-old man presented to our hospital with a swollen lesion in the left flank. A mass, 19 cm in diameter, was detected in the retroperitoneal space by computed tomography. We suspected the presence of a chronic expanding hematoma, soft tissue tumor, or left renal artery aneurysm. Surgical treatment was performed. However, postoperative histopathological examination indicated that the mass was a nonmalignant chronic expanding hematoma. No recurrence was observed during a 2-year follow-up period. Conclusion In patients without a history of trauma who present slowly growing masses, the differential diagnosis should include chronic expanding hematoma in addition to cysts and soft tissue tumors. Moreover, the use of magnetic resonance imaging and computed tomography is essential to differentiate between chronic expanding hematoma and soft tissue tumors. PMID:24237992

Full-thickness skin with mature hair follicles generated from tissue culture expanded human cells.

PubMed

Wu, Xunwei; Scott, Larry; Washenik, Ken; Stenn, Kurt

2014-12-01

The goal of regenerative medicine is to reconstruct fully functional organs from tissue culture expanded human cells. In this study, we report a method for human reconstructed skin (hRSK) when starting with human cells. We implanted tissue culture expanded human epidermal and dermal cells into an excision wound on the back of immunodeficient mice. Pigmented skin covered the wound 4 weeks after implantation. Hair shafts were visible at 12 weeks and prominent at 14 weeks. Histologically, the hRSK comprises an intact epidermis and dermis with mature hair follicles, sebaceous glands and most notably, and unique to this system, subcutis. Morphogenesis, differentiation, and maturation of the hRSK mirror the human fetal process. Human antigen markers demonstrate that the constituent cells are of human origin for at least 6 months. The degree of new skin formation is most complete when using tissue culture expanded cells from fetal skin, but it also occurs with expanded newborn and adult cells; however, no appendages formed when we grafted both adult dermal and epidermal cells. The hRSK system promises to be valuable as a laboratory model for studying biological, pathological, and pharmaceutical problems of human skin.

Guided bone regeneration and implant placement in association with a coronally positioned palatal sliding flap: a 17-year follow-up case report.

PubMed

Maiorana, Carlo; Poli, Pier Paolo; Beretta, Mario

2018-05-21

The aim of the present case report was to show the 17-year hard and soft tissues stability of guided bone regeneration procedure associated with dental implants insertion. A 52-year-old male patient presented with a partial edentulism in the upper right maxilla. A graft consisting of deproteinized bovine bone mineral and autogenous bone stabilized by a non-resorbable expanded polytetrafluoroethylene membrane was used to reconstruct the missing bone applying the biological principles of guided bone regeneration. Dental implants were inserted simultaneously in a prosthetically driven position. Soft tissues were managed with a coronally positioned palatal sliding flap technique to obtain a primary intention healing. The healing proceeded uneventfully, and after 8 months the re-entry procedure was carried out. The defect was three-dimensionally filled by newly formed bone in an ongoing maturation phase. The regenerated bone appeared strictly integrated within the surrounding hard tissue and well vascularized. Temporary crowns were left in situ for 6 months, and definitive metal-ceramic definitive prosthesis were finally cemented and delivered to the patient. No complications occurred during the follow-up period. Clinical follow-up recalls were planned yearly, while radiological exams consisting of orthopantomographs and intra-oral radiographs were performed at 1 year, 8 years, 12 years, and 17 years after the implants insertion. The latest follow-up visit performed after 17 years from the bone augmentation procedure showed clinically stable gingival levels. No radiographic signs of peri-implantitis were observed. Mesial and distal marginal bone levels remained almost unchanged within the physiological threshold. This case report highlighted the effectiveness of the guided bone regeneration technique over a long-term follow-up. Interestingly, the use of a palatal sliding flap repositioned coronally provided sufficient amount of buccal keratinized mucosa. This may had improved the clinical stability of soft tissues preventing at the same time the likelihood of developing peri-implant disease.

The TopClosure® 3S System, for skin stretching and a secure wound closure.

PubMed

Topaz, Moris; Carmel, Narin-Nard; Silberman, Adi; Li, Ming Sen; Li, Yong Zhong

2012-07-01

The principle of stretching wound margins for primary wound closure is commonly practiced and used for various skin defects, leading at times to excessive tension and complications during wound closure. Different surgical techniques, skin stretching devices and tissue expanders have been utilized to address this issue. Previously designed skin stretching devices resulted in considerable morbidity. They were invasive by nature and associated with relatively high localized tissue pressure, frequently leading to necrosis, damage and tearing of skin at the wound margins. To assess the clinical effectiveness and performance and, to determine the safety of TopClosure® for gradual, controlled, temporary, noninvasive and invasive applications for skin stretching and secure wound closing, the TopClosure® device was applied to 20 patients for preoperative skin lesion removal and to secure closure of a variety of wound sizes. TopClosure® was reinforced with adhesives, staples and/or surgical sutures, depending on the circumstances of the wound and the surgeon's judgment. TopClosure® was used prior to, during and/or after surgery to reduce tension across wound edges. No significant complications or adverse events were associated with its use. TopClosure® was effectively used for preoperative skin expansion in preparation for dermal resection (e.g., congenital nevi). It aided closure of large wounds involving significant loss of skin and soft tissue by mobilizing skin and subcutaneous tissue, thus avoiding the need for skin grafts or flaps. Following surgery, it was used to secure closure of wounds under tension, thus improving wound aesthetics. A sample case study will be presented. We designed TopClosure®, an innovative device, to modify the currently practiced concept of wound closure by applying minimal stress to the skin, away from damaged wound edges, with flexible force vectors and versatile methods of attachment to the skin, in a noninvasive or invasive manner.

Reduction and temporary stabilization of Tile C pelvic ring injuries using a posteriorly based external fixation system.

PubMed

Martin, Murphy P; Rojas, David; Mauffrey, Cyril

2018-07-01

Tile C pelvic ring injuries are challenging to manage even in the most experienced hands. The majority of such injuries can be managed using percutaneous reduction techniques, and the posterior ring can be stabilized using percutaneous transiliac-transsacral screw fixation. However, a subgroup of patients present with inadequate bony corridors, significant sacral zone 2 comminution or significant lateral/vertical displacement of the hemipelvis through a complete sacral fracture. Percutaneous strategies in such circumstances can be dangerous. Those patients may benefit from prone positioning and open reduction of the sacral fracture with fixation through tension band plating or lumbo-pelvic fixation. Soft tissue handling is critical, and direct reduction techniques around the sacrum can be difficult due to the complex anatomy and the fragile nature of the sacrum making clamp placement and tightening a challenge. In this paper, we propose a mini-invasive technique of indirect reduction and temporary stabilization, which is soft tissue friendly and permits maintenance of reduction during definitive fixation surgical.

Sensibility of Teeth Having Based versus Non-Based Amalgam Restorations: A Clinical Study.

DTIC Science & Technology

1983-04-01

Nervous control of blood circulation in dental pulp and the periodontal tissues . p. 139-44. (In Emmelin, N., and Sotterman, Y. eds. Oral physiology. New...using the direct tissue radioautography technique. Oral Surg., Oral Ned., Oral Path., 4:1461-4, Nov. 1951. 132. Scott, H.M. Reduction of sensitivity by...ever being placed underneath his amalgam temporaries. In 1868, "Hills soft stopping" was recommended for use as a palliative underneath amalgam when

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rubin, R.L.; Doku, H.C.

In recent years, therapeutic radiology has been used extensively in the management of head and neck malignancies. An increasing number of the population who have been exposed to such therapy are being seen by the dentist for dental treatment. It is recognized that radiation therapy may cause temporary and permanent alterations in tissue. A discussion of the various therapeutic modalities and their side effects on the oral tissues has been presented to aid the dental practitioner in understanding the problems and care of such patients. (auth)

Serial Tissue Expansion at the Same Site in Pediatric Patients: Is the Subsequent Expansion Faster?

PubMed Central

Lee, Moon Ki; Park, Seong Oh; Choi, Tae Hyun

2017-01-01

Background Serial tissue expansion is performed to remove giant congenital melanocytic nevi. However, there have been no studies comparing the expansion rate between the subsequent and preceding expansions. In this study, we analyzed the rate of expansion in accordance with the number of surgeries, expander location, expander size, and sex. Methods A retrospective analysis was performed in pediatric patients who underwent tissue expansion for giant congenital melanocytic nevi. We tested four factors that may influence the expansion rate: The number of surgeries, expander location, expander size, and sex. The rate of expansion was calculated by dividing the ‘inflation amount’ by the ‘expander size’. Results The expansion rate, compared with the first-time group, was 1.25 times higher in the second-or-more group (P=0.04) and 1.84 times higher in the third-or-more group (P<0.01). The expansion rate was higher at the trunk than at other sites (P<0.01). There was a tendency of lower expansion rate for larger expanders (P=0.03). Sex did not affect the expansion rate. Conclusions There was a positive correlation between the number of surgeries and the expansion rate, a positive correlation between the expander location and the expansion rate, and a negative correlation between the expander size and the expansion rate. PMID:29076319

Is precarious employment more damaging to women's health than men's?

PubMed

Menéndez, María; Benach, Joan; Muntaner, Carles; Amable, Marcelo; O'Campo, Patricia

2007-02-01

Current global economic trends in both developed and developing countries, including unregulated labor markets, trade competition and technological change, have greatly expanded a complex labor market situation characterised by many employees working under temporary work status, job insecurity, low social protection and low income level. Although the health of women is disproportionately affected by workplace flexibility, this has been largely ignored. The main purpose of this paper is to draw attention to this relevant but neglected topic.

Novel use of tissue expander for dilation of oropharyngeal stenosis.

PubMed

Banerjee, Debdeep; Wang, James C; Demke, Joshua C

2014-11-01

Naso/oropharyngeal stenoses are uncommon surgical complications. We present a child having undergone previous adenoidectomy without complication who developed naso/oropharyngeal scarring after subsequent tonsillectomy. She presented with nasal obstruction and frequent gasping at night worrisome for obstructive sleep apnea. Scar was initially excised and the defect allografted. Conventional esophageal dilators were undersized, and ultimately a tissue expander was used intraoperatively as a balloon dilator. The patient's symptoms and sleep apnea resolved. We found use of a tissue expander as a balloon dilator to be at least minimally effective in dilating the oropharynx when all other methods at our disposal proved ineffective. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

[Kirschner wire transfixation of unstable ankle fractures: indication, surgical technique and outcomes].

PubMed

Marvan, J; Džupa, V; Bartoška, R; Kachlík, D; Krbec, M; Báča, V

2015-01-01

PURPOSE OF THE STUDY The aim of the study was to assess treatment outcomes in patients undergoing K-wire transfixation of unstable ankle fractures and compare the results with those of patients in whom it was possible to perform primary one-stage osteosynthesis. MATERIAL AND METHODS Between 2009 and 2012, a total of 358 patients (191 women and 167 men) had surgery for unstable ankle fracture. At 1-year follow-up, their subjective feelings, objective findings and ankle radiographs were evaluated. The fractures were categorised according to the Weber classification. A patient group treated by one-stage osteosynthesis, a group with definitive transfixation and a group of patients in whom temporary transfixation was converted to definitive osteosynthesis were assessed and compared. RESULTS The group treated by one-stage osteosynthesis included 278 patients with an average age of 47 years; the group of 20 patients with definitive transfixation had an average age of 67 years, and the group of 60 patients who had temporary transfixation with subsequent conversion to internal osteosynthesis were 55 years on average. In the group with one-stage osteosynthesis, 223 (80%) ankle fractures on post-injury radiographs were associated with minor joint dislocations and 55 (20%) with major dislocations. On the other hand, the radiographs of the patients treated by temporary transfixation and delayed open reduction with internal fixation showed major dislocations in 38 (63%) and minor dislocations in the rest of the patients (37%); the difference between the two groups was statistically significant (p<0.001). Posterior malleolar fractures were most frequent in the group with temporary transfixation (60%) and least frequent in the group with primary osteosynthesis (44%); also this difference was statistically significant (p=0.032). At one-year follow-up, in the group with one-stage osteosynthesis, 220 patients (79%) had no radiographic signs of posttraumatic ankle osteoarthritis while, in the group with temporary transfixation, no radiographic evidence of ankle osteoarthritis was recorded in 25 (42%) patients. While tibiofibular synostosis was recorded in only few patients (9%) of the group with one-stage osteosynthesis, it showed a high occurrence in the group with temporary transfixation (35%). The patients with one-stage osteosynthesis (188/68%) had a higher proportion of excellent outcomes measured on the Olerund-Molander ankle scoring scale than the other two groups (temporary transfixation, 47%; definitive transfixation,10%); in both cases the difference was significant (p < 0.001 and p = 0.003, respectively). DISCUSSION In this study the morphological and clinical aspects of surgically treated ankle fractures were assessed. The patients with one-stage osteosynthesis were compared with those treated by temporary or definitive transfixation. The majority of patients undergoing temporary transfixation had a fractured posterior margin of the tibia and major ankle joint dislocation, which suggested serious injuries to bone and ligament structures. Generally, the use of only two K-wires inserted through the calcaneus and talus into the distal tibia is recommended. Patients with K-wire transfixation usually require a longer hospital stay because of the serious nature of their injuries. CONCLUSIONS The therapy of choice for unstable ankle fractures is one-stage osteosynthesis. Temporary transfixation is an effective method of primary management when an unstable fracture cannot be treated by definitive osteosynthesis at the early stage due to local or general health conditions of the patient. The temporary transfixation provides good alignment of the ankle joint necessary for successful healing of soft tissues. A higher occurrence of post-traumatic ankle osteoarthritis, ossification and distal tibiotalar synostosis found in the patients treated by temporary transfixation is more related to serious types of ankle fractures the patient had suffered than to the method itself. Key words: unstable ankle fracture, soft tissue condition, indications for transfixation, treatment outcome.

Treatment of congenital anophthalmos with self-inflating polymer expanders: a new method.

PubMed

Wiese, K G; Vogel, M; Guthoff, R; Gundlach, K K

1999-04-01

Congenital anophthalmos is a rare malformation in which the optic vesicle fails to develop. This leads to a small bony orbit, a constricted mucosal socket, short eyelids, reduced palpebral fissure and malar hypoplasia. The treatment includes both aesthetic and functional aspects. Therefore, a two-step procedure is described using a new self-inflating hydrogel expander. A lens-shaped expander with a diameter of 8 mm expands the lids and the mucosal socket to allow insertion of an eye prosthesis. As a second step, orbital expansion is performed with a spherical device. The expanders absorb lacrimal fluid from the mucosal socket or tissue fluid and start swelling when implanted in the orbital tissue. The insertion of an expander into the orbit as well as into the conjunctival pocket including its fixation by a single suture took only a few minutes and was an easy procedure. The expansion of the small conjunctival sockets was successfully completed in all cases within a period of 2-4 weeks. The weight (= volume in ml) of devices increased from 0.15-1.5 g (lens-shaped expander; weight in grams = volume in ml) respectively, 0.3-3.5 g (spherical device). The expanders inserted in orbital tissue increased from 0.4-4.4 g. This is equivalent to a 10 to 11 fold increase in their water-free volumes. Orbital expansion with spherical devices in combination with the inserted eye prosthesis enlarges the lid and palpebral fissures also. In contrast to conventional silicon balloon expanders, the procedure using self-inflating hydrogel expanders is simple and highly efficient.

Latissimus dorsi myocutaneous flap for breast reconstruction: bad rap or good flap?

PubMed

Perdikis, Galen; Koonce, Stephanie; Collis, George; Eck, Dustin

2011-01-01

This article serves to review latissimus dorsi myocutaneous flap as an option for breast reconstruction postmastectomy. Since the introduction of the latissimus dorsi myocutaneous flap in the late 1970s, its use has always been as a secondary technique, particularly after the development of the transverse rectus abdominus myocutaneous flap in the 1980s. A literature review of the history of latissimus dorsi myocutaneous flap utilized for breast reconstruction as well as a review of our institution's experience with latissimus dorsi myocutaneous flap and tissue expander placement was performed. There remains a paucity of published studies investigating latissimus dorsi myocutaneous flap for breast reconstruction. Most studies have small numbers and do not utilize tissue expanders. More recently several small studies have been published that show acceptably low complication rates with aesthetically pleasing outcomes when latissimus dorsi myocutaneous flap is employed with a tissue expander. At our institution, we have employed latissimus dorsi myocutaneous flap with tissue expander placement for both delayed and immediate reconstruction with subsequent replacement with a permanent implant with a capsular contraction rate of 10.5%. Our data and others more recently published demonstrate very acceptable capsular contracture rates and aesthetic outcomes, particularly when an expander is utilized. The latissimus dorsi myocutaneous flap remains an excellent choice for breast reconstruction with a low risk of complications.

Histologic analysis of fetal bovine derived acellular dermal matrix in tissue expander breast reconstruction.

PubMed

Gaster, Richard S; Berger, Aaron J; Monica, Stefanie D; Sweeney, Robert T; Endress, Ryan; Lee, Gordon K

2013-04-01

This study seeks to determine human host response to fetal bovine acellular dermal matrix (ADM) in staged implant-based breast reconstruction. A prospective study was performed for patients undergoing immediate breast reconstruction with tissue expander placement and SurgiMend acellular fetal bovine dermis. At the time of exchange for permanent implant, we obtained tissue specimens of SurgiMend and native capsule. Histological and immunohistochemical assays were performed to characterize the extent of ADM incorporation/degradation, host cell infiltration, neovascularization, inflammation, and host replacement of acellular fetal bovine collagen. Seventeen capsules from 12 patients were included in our study. The average "implantation" time of SurgiMend was 7.8 months (range, 2-23 months). Histological analysis of the biopsy of tissue revealed rare infiltration of host inflammatory cells, even at 23 months. One patient had an infection requiring removal of the tissue expander at 2 months. Contracture, inflammatory changes, edema, and polymorphonuclear leukocyte infiltration were rare in the ADM. An acellular capsule was seen in many cases, at the interface of SurgiMend with the tissue expander. SurgiMend demonstrated a very infrequent inflammatory response. An antibody specific to bovine collagen allowed for direct identification of bovine collagen separate from human collagen. Cellular infiltration and neovascularization of SurgiMend correlated with the quality of the mastectomy skin flap rather than the duration of implantation. Future studies are needed to further characterize the molecular mechanisms underlying tissue incorporation of this product.

Using a discrete-event simulation to balance ambulance availability and demand in static deployment systems.

PubMed

Wu, Ching-Han; Hwang, Kevin P

2009-12-01

To improve ambulance response time, matching ambulance availability with the emergency demand is crucial. To maintain the standard of 90% of response times within 9 minutes, the authors introduce a discrete-event simulation method to estimate the threshold for expanding the ambulance fleet when demand increases and to find the optimal dispatching strategies when provisional events create temporary decreases in ambulance availability. The simulation model was developed with information from the literature. Although the development was theoretical, the model was validated on the emergency medical services (EMS) system of Tainan City. The data are divided: one part is for model development, and the other for validation. For increasing demand, the effect was modeled on response time when call arrival rates increased. For temporary availability decreases, the authors simulated all possible alternatives of ambulance deployment in accordance with the number of out-of-routine-duty ambulances and the durations of three types of mass gatherings: marathon races (06:00-10:00 hr), rock concerts (18:00-22:00 hr), and New Year's Eve parties (20:00-01:00 hr). Statistical analysis confirmed that the model reasonably represented the actual Tainan EMS system. The response-time standard could not be reached when the incremental ratio of call arrivals exceeded 56%, which is the threshold for the Tainan EMS system to expand its ambulance fleet. When provisional events created temporary availability decreases, the Tainan EMS system could spare at most two ambulances from the standard configuration, except between 20:00 and 01:00, when it could spare three. The model also demonstrated that the current Tainan EMS has two excess ambulances that could be dropped. The authors suggest dispatching strategies to minimize the response times in routine daily emergencies. Strategies of capacity management based on this model improved response times. The more ambulances that are out of routine duty, the better the performance of the optimal strategies that are based on this model.

Tissue expander stimulated lengthening of arteries (TESLA) induces early endothelial cell proliferation in a novel rodent model.

PubMed

Potanos, Kristina; Fullington, Nora; Cauley, Ryan; Purcell, Patricia; Zurakowski, David; Fishman, Steven; Vakili, Khashayar; Kim, Heung Bae

2016-04-01

We examine the mechanism of aortic lengthening in a novel rodent model of tissue expander stimulated lengthening of arteries (TESLA). A rat model of TESLA was examined with a single stretch stimulus applied at the time of tissue expander insertion with evaluation of the aorta at 2, 4 and 7day time points. Measurements as well as histology and proliferation assays were performed and compared to sham controls. The aortic length was increased at all time points without histologic signs of tissue injury. Nuclear density remained unchanged despite the increase in length suggesting cellular hyperplasia. Cellular proliferation was confirmed in endothelial cell layer by Ki-67 stain. Aortic lengthening may be achieved using TESLA. The increase in aortic length can be achieved without tissue injury and results at least partially from cellular hyperplasia. Further studies are required to define the mechanisms involved in the growth of arteries under increased longitudinal stress. Copyright © 2015 Elsevier Inc. All rights reserved.

MECHANISMS IN ENDOCRINOLOGY: Skeletal muscle lipotoxicity in insulin resistance and type 2 diabetes: a causal mechanism or an innocent bystander?

PubMed

Brøns, Charlotte; Grunnet, Louise Groth

2017-02-01

Dysfunctional adipose tissue is associated with an increased risk of developing type 2 diabetes (T2D). One characteristic of a dysfunctional adipose tissue is the reduced expandability of the subcutaneous adipose tissue leading to ectopic storage of fat in organs and/or tissues involved in the pathogenesis of T2D that can cause lipotoxicity. Accumulation of lipids in the skeletal muscle is associated with insulin resistance, but the majority of previous studies do not prove any causality. Most studies agree that it is not the intramuscular lipids per se that causes insulin resistance, but rather lipid intermediates such as diacylglycerols, fatty acyl-CoAs and ceramides and that it is the localization, composition and turnover of these intermediates that play an important role in the development of insulin resistance and T2D. Adipose tissue is a more active tissue than previously thought, and future research should thus aim at examining the exact role of lipid composition, cellular localization and the dynamics of lipid turnover on the development of insulin resistance. In addition, ectopic storage of fat has differential impact on various organs in different phenotypes at risk of developing T2D; thus, understanding how adipogenesis is regulated, the interference with metabolic outcomes and what determines the capacity of adipose tissue expandability in distinct population groups is necessary. This study is a review of the current literature on the adipose tissue expandability hypothesis and how the following ectopic lipid accumulation as a consequence of a limited adipose tissue expandability may be associated with insulin resistance in muscle and liver. © 2017 European Society of Endocrinology.

Bigelow Expandable Activity Module (BEAM) - ISS Inflatable Module Technology Demonstration

NASA Technical Reports Server (NTRS)

Dasgupta, Rajib; Munday, Steve; Valle, Gerard D.

2014-01-01

INNOVATION: BEAM is a pathway project demonstrating the design, fabrication, test, certification, integration, operation, on-orbit performance, and disposal of the first ever man-rated space inflatable structure. The groundwork laid through the BEAM project will support developing and launching a larger inflatable space structure with even greater mass per volume (M/V) advantages need for longer space missions. OVERVIEW: Inflatable structures have been shown to have much lower mass per volume ratios (M/V) when compared with conventional space structures. BEAM is an expandable structure, launched in a packed state, and then expanded once on orbit. It is a temporary experimental module to be used for gathering structural, thermal, and radiation data while on orbit. BEAM will be launched on Space X-8, be extracted from the dragon trunk, and will attach to ISS at Node 3- Aft. BEAM performance will be monitored over a two-year period and then BEAM will be jettison using the SSRMS.

[Experimental study of PVPP/silicone composite automatic expanded material as implants].

PubMed

Yin, Wei-min; Gao, Jian-hua; Yang, Qing-fang; Lu, Feng; Ye, Jia-jia

2009-03-01

To study the feasibility of Polyvinylpolypyrrolidone (PVPP)/silicone composite automatic expanded material as implants. The PVPP hydrogel was mixed with silicone through the location at the high temperature. Implants with different ratio of PVPP to silicone were placed under the back and nose skin in 24 New Zealand rabbits. The surrounding tissue reaction, material and skin expansion were observed and compared with those with pure silicone implants. The study lasted for 200 days. Compared with pure silicone implants, the composite material could expand automatically and stop expanding at about 2 weeks after implantation. Histological study showed similar inflectional and foreign body reaction around the composite material and the pure silicone. Compared with pure silicone, the PVPP/silicone composite implant has the advantage of automatic expansion, so as to expand the soft tissue.

Pms2 Suppresses Large Expansions of the (GAA·TTC)n Sequence in Neuronal Tissues

PubMed Central

Bourn, Rebecka L.; De Biase, Irene; Pinto, Ricardo Mouro; Sandi, Chiranjeevi; Al-Mahdawi, Sahar; Pook, Mark A.; Bidichandani, Sanjay I.

2012-01-01

Expanded trinucleotide repeat sequences are the cause of several inherited neurodegenerative diseases. Disease pathogenesis is correlated with several features of somatic instability of these sequences, including further large expansions in postmitotic tissues. The presence of somatic expansions in postmitotic tissues is consistent with DNA repair being a major determinant of somatic instability. Indeed, proteins in the mismatch repair (MMR) pathway are required for instability of the expanded (CAG·CTG)n sequence, likely via recognition of intrastrand hairpins by MutSβ. It is not clear if or how MMR would affect instability of disease-causing expanded trinucleotide repeat sequences that adopt secondary structures other than hairpins, such as the triplex/R-loop forming (GAA·TTC)n sequence that causes Friedreich ataxia. We analyzed somatic instability in transgenic mice that carry an expanded (GAA·TTC)n sequence in the context of the human FXN locus and lack the individual MMR proteins Msh2, Msh6 or Pms2. The absence of Msh2 or Msh6 resulted in a dramatic reduction in somatic mutations, indicating that mammalian MMR promotes instability of the (GAA·TTC)n sequence via MutSα. The absence of Pms2 resulted in increased accumulation of large expansions in the nervous system (cerebellum, cerebrum, and dorsal root ganglia) but not in non-neuronal tissues (heart and kidney), without affecting the prevalence of contractions. Pms2 suppressed large expansions specifically in tissues showing MutSα-dependent somatic instability, suggesting that they may act on the same lesion or structure associated with the expanded (GAA·TTC)n sequence. We conclude that Pms2 specifically suppresses large expansions of a pathogenic trinucleotide repeat sequence in neuronal tissues, possibly acting independently of the canonical MMR pathway. PMID:23071719

Pms2 suppresses large expansions of the (GAA·TTC)n sequence in neuronal tissues.

PubMed

Bourn, Rebecka L; De Biase, Irene; Pinto, Ricardo Mouro; Sandi, Chiranjeevi; Al-Mahdawi, Sahar; Pook, Mark A; Bidichandani, Sanjay I

2012-01-01

Expanded trinucleotide repeat sequences are the cause of several inherited neurodegenerative diseases. Disease pathogenesis is correlated with several features of somatic instability of these sequences, including further large expansions in postmitotic tissues. The presence of somatic expansions in postmitotic tissues is consistent with DNA repair being a major determinant of somatic instability. Indeed, proteins in the mismatch repair (MMR) pathway are required for instability of the expanded (CAG·CTG)(n) sequence, likely via recognition of intrastrand hairpins by MutSβ. It is not clear if or how MMR would affect instability of disease-causing expanded trinucleotide repeat sequences that adopt secondary structures other than hairpins, such as the triplex/R-loop forming (GAA·TTC)(n) sequence that causes Friedreich ataxia. We analyzed somatic instability in transgenic mice that carry an expanded (GAA·TTC)(n) sequence in the context of the human FXN locus and lack the individual MMR proteins Msh2, Msh6 or Pms2. The absence of Msh2 or Msh6 resulted in a dramatic reduction in somatic mutations, indicating that mammalian MMR promotes instability of the (GAA·TTC)(n) sequence via MutSα. The absence of Pms2 resulted in increased accumulation of large expansions in the nervous system (cerebellum, cerebrum, and dorsal root ganglia) but not in non-neuronal tissues (heart and kidney), without affecting the prevalence of contractions. Pms2 suppressed large expansions specifically in tissues showing MutSα-dependent somatic instability, suggesting that they may act on the same lesion or structure associated with the expanded (GAA·TTC)(n) sequence. We conclude that Pms2 specifically suppresses large expansions of a pathogenic trinucleotide repeat sequence in neuronal tissues, possibly acting independently of the canonical MMR pathway.

Reconstruction of Nasal Cleft Deformities Using Expanded Forehead Flaps: A Case Series.

PubMed

Ramanathan, Manikandhan; Sneha, Pendem; Parameswaran, Ananthnarayanan; Jayakumar, Naveen; Sailer, Hermann F

2014-12-01

Reconstruction of the nasal clefts is a challenging task considering the nasal anatomic complexity and their possible association with craniofacial defects. The reconstruction of these defects needs extensive amounts of soft tissue that warrant the use of forehead flaps. Often presence of cranial defects and low hairline compromise the amount of tissue available for reconstruction warrenting tissue expansion. To evaluate the efficacy of tissue expansion in reconstruction of congenital nasal clefts. 9 patients with congenital nasal clefts involving multiple sub units were taken up for nasal reconstruction with expanded forehead flaps. The average amount of expansion needed was 200 ml. The reconstruction was performed in 3 stages. Expanded forehead flaps proved to be best modality for reconstruction providing the skin cover needed for ala, columella and dorsum with minimal scarring at the donor site. Expansion of the forehead flap is a viable option for multiple sub unit reconstruction in congenital nasal cleft deformities.

Incidence of Bradycardia and Outcomes of Patients Who Underwent Orbital Atherectomy Without a Temporary Pacemaker.

PubMed

Lee, Michael S; Nguyen, Heajung; Shlofmitz, Richard

2017-02-01

We analyzed the incidence of bradycardia and the safety of patients with severely calcified coronary lesions who underwent orbital atherectomy without the insertion of a temporary pacemaker. The presence of severely calcified coronary lesions can increase the complexity of percutaneous coronary intervention due to the difficulty in advancing and optimally expanding the stent. High-pressure inflations to predilate calcified lesions may cause angiographic complications like perforation and dissection. Suboptimal stent expansion is associated with stent thrombosis and restenosis. Orbital atherectomy safely and effectively modifies calcified plaque to facilitate optimal stent expansion. The incidence of bradycardia in orbital atherectomy is unknown. Fifty consecutive patients underwent orbital atherectomy from February 2014 to September 2016 at our institution, none of whom underwent insertion of a temporary pacemaker. The final analysis included 47 patients in this retrospective study as 3 patients were excluded because of permanent pacemaker implantation. The primary endpoint was significant bradycardia, defined as bradycardia requiring emergent pacemaker placement or a heart rate <50 bpm at the end of atherectomy. The primary endpoint occurred in 4% of all patients, all driven by patients who experienced a heart rate decreasing to <50 bpm. The major adverse cardiac and cerebral event rate was 6%, driven by death (2%) and myocardial infarction (4%). No patient experienced target-vessel revascularization, stroke, or stent thrombosis. Angiographic complications included perforation in 2%, slow-flow in 4%, and flow-limiting dissection in 0%. Significant bradycardia was uncommon during orbital atherectomy. Performing orbital atherectomy without a temporary pacemaker appears to be safe.

Weight Measurement and Volumetric Displacement of Breast Implants and Tissue Expanders: Why Port and Shell Volumes Matter in Breast Reconstruction, Augmentation, and Revision.

PubMed

Wenzel, Chad G; Wacholtz, William F; Janssen, David A; Bengtson, Bradley P

2015-10-01

There are significant differences in weight and volumetric characteristics between silicone and saline breast implants of which most plastic surgeons are unaware. Phase I of this study was a weight measurement focused on recording differences in the weight of saline volumes instilled versus recorded weights of saline implants and expanders. Phase II compared displaced volume differences of tissue expanders with instilled volumes. As a result of this study, surgeons should now be able to precisely calculate the volume created for breast pocket development, allowing for accurate matching of expander and final breast implant. Copyright © 2015 Elsevier Inc. All rights reserved.

The experimental and numerical investigation of pistol bullet penetrating soft tissue simulant.

PubMed

Wang, Yongjuan; Shi, Xiaoning; Chen, Aijun; Xu, Cheng

2015-04-01

Gelatin, a representative simulant for soft tissue of the human body, was used to study the effects of 9 mm pistol bullet's penetration. The behavior of a bullet penetrating gelatin was quantified by the temporary cavity sizes in ballistic gelatin and the pressure values of bullet's impact. A numerical simulation model of a bullet penetrating the soft tissue simulant gelatin was built using the finite element method (FEM). The model was validated by the comparison between the numerical results and the experimental results. During a bullet penetrating ballistic gelatin, four stages were clearly observed in both the experiment and the numerical simulation: a smooth attenuation stage, a rolling stage, a full penetration stage, and a stage of expansion and contraction. The cavity evolution, equivalent stress field and the strain field in gelatin were analyzed by numerical simulation. Moreover, the effects of the bullet's impact velocities and angles of incidence on the temporary cavity in gelatin, its velocity attenuation, and its rolling angle were investigated, as well as the bullet's resistance and energy variation. The physical process and the interactive mechanism during a pistol bullet penetrating gelatin were comprehensively revealed. This may be significant for research in wound ballistics. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Outcome of Conventional Adipose Tissue Grafting for Contour Deformities of Face and Role of Ex Vivo Expanded Adipose Tissue-Derived Stem Cells in Treatment of Such Deformities.

PubMed

Bashir, Muhammad Mustehsan; Sohail, Muhammad; Bashir, Afzaal; Khan, Farid Ahmad; Jan, Sadia Nosheen; Imran, Muhammad; Ahmad, Fridoon Jawad; Choudhery, Mahmood S

2018-02-23

To evaluate the outcomes of conventional fat grafting for facial contour deformities and to describe clinical outcome of a patient with contour deformity of face treated with ex vivo expanded adipose tissue-derived mesenchymal stem cells (ASCs) enriched fat graft. The Department of Plastic Surgery and Tissue Engineering and Regenerative Medicine Laboratory, King Edward Medical University/Mayo Hospital, Lahore, from September 2015 to September 2017. Patients with contour deformities of face requiring soft tissue augmentation were included. Fat was harvested, processed, and injected following a standard protocol. Both subjective and objective assessments were performed and complications were also noted. Twenty-five patients underwent 51 fat-grafting sessions over a period of 24 months. Eighteen (72%) patients underwent multiple fat-grafting sessions. Mean (standard deviation) soft tissue thickness after 72 hours and 6 months of first fat graft session was 18.62 (7.2) and 12.88 (6.21) mm, respectively, which corresponds to 30.77 (13)% reduction of transplanted fat. Physician and patient assessment scores were 3.42 (0.92) and 4 (1.04), respectively. Few minor complications were observed. In the patient undergoing ex vivo expanded ASCs enriched fat graft, there was minimal decrease in soft tissue thickness of treated area (44 mm vs 42 mm) 6 months postoperatively and patient was highly satisfied with the outcome after the single session. Conventional fat grafting is safe for correction of facial contour deformities. However, procedure needs to be repeated multiple times to produce satisfactory results. Beneficial effects of ex vivo expanded ASCs enriched fat grafting have a potential to alter the current treatment paradigm of fat grafting for soft tissue reconstruction.

Latissimus Dorsi Myocutaneous Flap for Breast Reconstruction: Bad Rap or Good Flap?

PubMed Central

Perdikis, Galen; Koonce, Stephanie; Collis, George; Eck, Dustin

2011-01-01

Objective: This article serves to review latissimus dorsi myocutaneous flap as an option for breast reconstruction postmastectomy. Since the introduction of the latissimus dorsi myocutaneous flap in the late 1970s, its use has always been as a secondary technique, particularly after the development of the transverse rectus abdominus myocutaneous flap in the 1980s. Methods: A literature review of the history of latissimus dorsi myocutaneous flap utilized for breast reconstruction as well as a review of our institution's experience with latissimus dorsi myocutaneous flap and tissue expander placement was performed. Results: There remains a paucity of published studies investigating latissimus dorsi myocutaneous flap for breast reconstruction. Most studies have small numbers and do not utilize tissue expanders. More recently several small studies have been published that show acceptably low complication rates with aesthetically pleasing outcomes when latissimus dorsi myocutaneous flap is employed with a tissue expander. At our institution, we have employed latissimus dorsi myocutaneous flap with tissue expander placement for both delayed and immediate reconstruction with subsequent replacement with a permanent implant with a capsular contraction rate of 10.5%. Our data and others more recently published demonstrate very acceptable capsular contracture rates and aesthetic outcomes, particularly when an expander is utilized. Conclusion: The latissimus dorsi myocutaneous flap remains an excellent choice for breast reconstruction with a low risk of complications. PMID:22031843

Human Factors Validation of the AeroForm Tissue Expander System for Breast Reconstruction.

PubMed

Kelley, Kathy; Kim, Jennie

The tissue expansion process using traditional saline expanders is lengthy and uncomfortable. A new technology has been developed, providing a needle-free option implanted after a mastectomy, and is activated by a handheld remote control releasing small amounts (10 cc) of carbon dioxide from an internal reservoir. The expander is gradually filled with CO2 resulting in mechanical stretching of the overlying tissue. The AeroForm System has been evaluated in a series of clinical trials including a randomized, controlled U.S. study comparing the AeroForm System with saline expanders. Results demonstrated patients can safely and reliably dose and complete their expansions in half the time compared to saline expanders. A human factors validation study was conducted in 8 patients to evaluate whether patients could correctly use the device to complete their expansion at home. The sessions were recorded and data on performance, behavioral, and subjective measures were collected and analyzed and submitted to the FDA as part of the U.S. marketing approval. All 8 participants were successful in using the controller to deliver a simulated dose. Participants found the device easy to use and the training material provided adequate to understand use of the controller. For women who choose 2-stage breast reconstruction, a new safe and effective option is available for tissue expansion, offering a convenient and empowering alternative. The human factors validation study conducted confirmed the simplicity of the device and further validated that the device can be used safely and effectively for breast tissue expansion.

An Experimental Study on the Impact of Different-frequency Elastic Waves on Water Retention Curve

NASA Astrophysics Data System (ADS)

Deng, J. H.; Dai, J. Y.; Lee, J. W.; Lo, W. C.

2017-12-01

ABSTEACTOver the past few decades, theoretical and experimental studies on the connection between elastic wave attributes and the physical properties of a fluid-bearing porous medium have attracted the attention of many scholars in fields of porous medium flow and hydrogeology. It has been previously determined that the transmission of elastic waves in a porous medium containing two immiscible fluids will have an effect on the water retention curve, but it has not been found that the water retention curve will be affected by the frequency of elastic vibration waves or whether the effect on the soil is temporary or permanent. This research is based on a sand box test in which the soil is divided into three layers (a lower, middle, and upper layer). In this case, we discuss different impacts on the water retention curve during the drying process under sound waves (elastic waves) subject to three frequencies (150Hz, 300Hz, and 450Hz), respectively. The change in the water retention curve before and after the effect is then discussed. In addition, how sound waves affect the water retention curve at different depths is also observed. According to the experimental results, we discover that sound waves can cause soil either to expand or to contract. When the soil is induced to expand due to sound waves, it can contract naturally and return to the condition it was in before the influence of the sound waves. On the contrary, when the soil is induced to contract, it is unable to return to its initial condition. Due to the results discussed above, it is suggested that sound waves causing soil to expand have a temporary impact while those causing soil to contract have a permanent impact. In addition, our experimental results show how sound waves affect the water retention curve at different depths. The degree of soil expansion and contraction caused by the sound waves will differ at various soil depths. Nevertheless, the expanding or contracting of soil is only subject to the frequency of sound waves. Key words: Elastic waves, Water retention curve, Sand box test.

Dosimetric impact of the AeroForm tissue expander in postmastectomy radiation therapy: an ex vivo analysis.

PubMed

Moni, Janaki; Saleeby, Jonathan; Bannon, Elizabeth; Lo, Yuan-Chyuan; Fitzgerald, Thomas J

2015-01-01

To evaluate the effect of the AeroForm (AirXpanders Inc, Palo Alto, CA) tissue expander on the dose distribution in a phantom from a simulated postmastectomy radiation treatment for breast cancer. Experiments were conducted to determine the effect on the dose distribution with the metallic reservoir irradiated independently and with the entire AeroForm tissue expander placed on a RANDO phantom (The Phantom Laboratory, Salem, NY). The metallic reservoir was irradiated on a block of solid water with film at various depths ranging from 0 to 8.2 cm from the surface. The intact 400 cc AeroForm was inflated to full capacity and irradiated while positioned on a RANDO phantom, with 12 optically stimulated luminescent dosimeters (OSLDs) placed at clinically relevant expander-tissue interface points. Film dosimetry with the reservoir perpendicular to film reveals 40% transmission at a depth of 0.7 cm, which increases to 60% at a depth of 8.2 cm. In the parallel position, the results vary depending on which area under the reservoir is examined, indicating that the reservoir is not a uniformly dense object. Testing of the intact expander on the phantom revealed that the average percent difference (measured vs expected dose) was 2.7%, σ = 6.2% with heterogeneity correction and 3.7%, σ = 2.4% without heterogeneity correction. The only position where the OSLD readings were consistently higher than the calculated dose by >5% was at position 1, just deep to the canister at the expander-phantom interface. At this position, the readings varied from 5.2% to 14.5%, regardless of heterogeneity correction. Film dosimetry demonstrated beam attenuation in the shadow of the metallic reservoir in the expander. This decrease in dose was not reproduced on the intact expander on the phantom designed to replicate a clinical setup. Copyright © 2015 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

Use of fibroblast growth factor 2 for expansion of chondrocytes and tissue engineering

NASA Technical Reports Server (NTRS)

Vunjak-Novakovic, Gordana (Inventor); Martin, Ivan (Inventor); Freed, Lisa E. (Inventor); Langer, Robert (Inventor)

2003-01-01

The present invention provides an improved method for expanding cells for use in tissue engineering. In particular the method provides specific biochemical factors to supplement cell culture medium during the expansion process in order to reproduce events occurring during embryonic development with the goal of regenerating tissue equivalents that resemble natural tissues both structurally and functionally. These specific biochemical factors improve proliferation of the cells and are capable of de-differentiation mature cells isolated from tissue so that the differentiation potential of the cells is preserved. The bioactive molecules also maintain the responsiveness of the cells to other bioactive molecules. Specifically, the invention provides methods for expanding chondrocytes in the presence of fibroblast growth factor 2 for use in regeneration of cartilage tissue.

Functionalized scaffolds to enhance tissue regeneration

PubMed Central

Guo, Baolin; Lei, Bo; Li, Peng; Ma, Peter X.

2015-01-01

Tissue engineering scaffolds play a vital role in regenerative medicine. It not only provides a temporary 3-dimensional support during tissue repair, but also regulates the cell behavior, such as cell adhesion, proliferation and differentiation. In this review, we summarize the development and trends of functional scaffolding biomaterials including electrically conducting hydrogels and nanocomposites of hydroxyapatite (HA) and bioactive glasses (BGs) with various biodegradable polymers. Furthermore, the progress on the fabrication of biomimetic nanofibrous scaffolds from conducting polymers and composites of HA and BG via electrospinning, deposition and thermally induced phase separation is discussed. Moreover, bioactive molecules and surface properties of scaffolds are very important during tissue repair. Bioactive molecule-releasing scaffolds and antimicrobial surface coatings for biomedical implants and scaffolds are also reviewed. PMID:25844177

Periapical tissue healing after post space preparation with or without use of a protection plug and root canal exposure to the oral environment. Study in dogs.

PubMed

Holland, Roberto; Manne, Luciana Noronha; de Souza, Valdir; Murata, Sueli Satomi; Dezan Júnior, Eloi

2007-01-01

The purpose of this study was to evaluate the influence of coronal leakage on the healing of dogs' periapical tissues after root canal filling, post space preparation and protection or not with a temporary sealer plug. Forty root canals of dogs' teeth were instrumented and filled by the lateral condensation technique with gutta-percha points and Endomethasone or CRCS sealers. After post space preparation, the remaining filling material was protected or not with a plug of temporary Coltosol sealer and exposed to the oral environment for 90 days. Thereafter, the animals were sacrificed and the specimens were removed and prepared for histomorphological and histobacteriological analysis. The findings revealed 35% of microbial leakage in the groups without plugs and 15% of leakage in the groups with plugs. Statistical analysis showed that the use of a Coltosol plug improved significantly the histomorphological results regardless of the type of root canal sealer (p=0.05) and that CRCS and Endomethasone sealers showed similar results (p>0.05).

Polylactic acid (PLA) controlled delivery carriers for biomedical applications.

PubMed

Tyler, Betty; Gullotti, David; Mangraviti, Antonella; Utsuki, Tadanobu; Brem, Henry

2016-12-15

Polylactic acid (PLA) and its copolymers have a long history of safety in humans and an extensive range of applications. PLA is biocompatible, biodegradable by hydrolysis and enzymatic activity, has a large range of mechanical and physical properties that can be engineered appropriately to suit multiple applications, and has low immunogenicity. Formulations containing PLA have also been Food and Drug Administration (FDA)-approved for multiple applications making PLA suitable for expedited clinical translatability. These biomaterials can be fashioned into sutures, scaffolds, cell carriers, drug delivery systems, and a myriad of fabrications. PLA has been the focus of a multitude of preclinical and clinical testing. Three-dimensional printing has expanded the possibilities of biomedical engineering and has enabled the fabrication of a myriad of platforms for an extensive variety of applications. PLA has been widely used as temporary extracellular matrices in tissue engineering. At the other end of the spectrum, PLA's application as drug-loaded nanoparticle drug carriers, such as liposomes, polymeric nanoparticles, dendrimers, and micelles, can encapsulate otherwise toxic hydrophobic anti-tumor drugs and evade systemic toxicities. The clinical translation of these technologies from preclinical experimental settings is an ever-evolving field with incremental advancements. In this review, some of the biomedical applications of PLA and its copolymers are highlighted and briefly summarized. Copyright © 2016 Elsevier B.V. All rights reserved.

Fertility preservation in young patients with cancer

PubMed Central

Suhag, Virender; Sunita, B. S.; Sarin, Arti; Singh, A. K.; Dashottar, S.

2015-01-01

Infertility can arise as a consequence of treatment of oncological conditions. The parallel and continued improvement in both the management of oncology and fertility cases in recent times has brought to the forefront the potential for fertility preservation in patients being treated for cancer. Many survivors will maintain their reproductive potential after the successful completion of treatment for cancer. However total body irradiation, radiation to the gonads, and certain high dose chemotherapy regimens can place women at risk for acute ovarian failure or premature menopause and men at risk for temporary or permanent azoospermia. Providing information about risk of infertility and possible interventions to maintain reproductive potential are critical for the adolescent and young adult population at the time of diagnosis. There are established means of preserving fertility before cancer treatment; specifically, sperm cryopreservation for men and in vitro fertilization and embryo cryopreservation for women. Several innovative techniques are being actively investigated, including oocyte and ovarian follicle cryopreservation, ovarian tissue transplantation, and in vitro follicle maturation, which may expand the number of fertility preservation choices for young cancer patients. Fertility preservation may also require some modification of cancer therapy; thus, patients’ wishes regarding future fertility and available fertility preservation alternatives should be discussed before initiation of therapy. PMID:26942145

Pitfalls in soft tissue sarcoma imaging: chronic expanding hematomas.

PubMed

Jahed, Kiarash; Khazai, Behnaz; Umpierrez, Monica; Subhawong, Ty K; Singer, Adam D

2018-01-01

Solid or nodular enhancement is typical of soft tissue sarcomas although high grade soft tissue sarcomas and those with internal hemorrhage often appear heterogeneous with areas of nonenhancement and solid or nodular enhancement. These MRI findings often prompt an orthopedic oncology referral, a biopsy or surgery. However, not all masses with these imaging findings are malignant. We report the multimodality imaging findings of two surgically proven chronic expanding hematomas (CEH) with imaging features that mimicked sarcomas. A third case of nonenhancing CEH of the lower extremity is also presented as a comparison. It is important that in the correct clinical scenario with typical imaging findings, the differential diagnosis of a chronic expanding hematoma be included in the workup of these patients. An image-guided biopsy of nodular tissue within such masses that proves to be negative for malignancy should not necessarily be considered discordant. A correct diagnosis may prevent a morbid unnecessary surgery and may indicate the need for a conservative noninvasive follow-up with imaging.

Porous Biodegradable Metals for Hard Tissue Scaffolds: A Review

PubMed Central

Yusop, A. H.; Bakir, A. A.; Shaharom, N. A.; Abdul Kadir, M. R.; Hermawan, H.

2012-01-01

Scaffolds have been utilized in tissue regeneration to facilitate the formation and maturation of new tissues or organs where a balance between temporary mechanical support and mass transport (degradation and cell growth) is ideally achieved. Polymers have been widely chosen as tissue scaffolding material having a good combination of biodegradability, biocompatibility, and porous structure. Metals that can degrade in physiological environment, namely, biodegradable metals, are proposed as potential materials for hard tissue scaffolding where biodegradable polymers are often considered as having poor mechanical properties. Biodegradable metal scaffolds have showed interesting mechanical property that was close to that of human bone with tailored degradation behaviour. The current promising fabrication technique for making scaffolds, such as computation-aided solid free-form method, can be easily applied to metals. With further optimization in topologically ordered porosity design exploiting material property and fabrication technique, porous biodegradable metals could be the potential materials for making hard tissue scaffolds. PMID:22919393

Two-photon Microscopy and Polarimetry for Assessment of Myocardial Tissue Organization

NASA Astrophysics Data System (ADS)

Archambault-Wallenburg, Marika

Optical methods can provide useful tissue characterization tools. For this project, two-photon microscopy and polarized light examinations (polarimetry) were used to assess the organizational state of myocardium in healthy, infarcted, and stem-cell regenerated states. Two-photon microscopy visualizes collagen through second-harmonic generation and myocytes through two-photon excitation autofluorescence, providing information on the composition and structure/organization of the tissue. Polarimetry measurements yield a value of linear retardance that can serve as an indicator of tissue anisotropy, and with a dual-projection method, information about the anisotropy axis orientation can also be extracted. Two-photon microscopy results reveal that stem-cell treated tissue retains more myocytes and structure than infarcted myocardium, while polarimetry findings suggest that the injury caused by temporary ligation of a coronary artery is less severe and more diffuse that than caused by a permanent ligation. Both these methods show potential for tissue characterization.

Soft-Tissue Injuries Associated With High-Energy Extremity Trauma: Principles of Management.

PubMed

Norris; Kellam

1997-01-01

The management of high-energy extremity trauma has evolved over the past several decades, and appropriate treatment of associated soft-tissue injuries has proved to be an important factor in achieving a satisfactory outcome. Early evaluation of the severely injured extremity is crucial. Severe closed injuries require serial observation of the soft tissues and early skeletal stabilization. Open injuries require early aggressive debridement of the soft tissues followed by skeletal stabilization. Temporary wound dressings should remain in place until definitive soft-tissue coverage has been obtained. Definitive soft-tissue closure will be expedited by serial debridements performed every 48 to 72 hours in a sterile environment. Skeletal union is facilitated by early bone grafting and/or modification of the stabilizing device. Aggressive rehabilitation, includ-ing early social reintegration, are crucial for a good functional outcome. Adherence to protocols is especially beneficial in the management of salvageable severely injured extremities.

Ocular cells and light: harmony or conflict?

PubMed

Jurja, Sanda; Hîncu, Mihaela; Dobrescu, Mihaela Amelia; Golu, Andreea Elena; Bălăşoiu, Andrei Theodor; Coman, Mălina

2014-01-01

Vision is based on the sensitivity of the eye to visible rays of the solar spectrum, which allows the recording and transfer of visual information by photoelectric reaction. Any electromagnetic radiation, if sufficiently intense, may cause damages in living tissues. In a changing environment, the aim of this paper is to point out the impact of light radiation on ocular cells, with its phototoxicity potential on eye tissues. In fact, faced with light and oxygen, the eye behaves like an ephemeral aggregate of unstable molecules, like a temporary crystallization threatened with entropia.

Comparison of Reconstructive Outcomes in Breast Cancer Patients With Preexisting Subpectoral Implants: Implant-Sparing Mastectomy With Delayed Implant Exchange Versus Immediate Tissue Expander Reconstruction.

PubMed

Parabkaharan, Sangeetha; Melody, Megan; Trotta, Rose; Lleshi, Amina; Sun, Weihong; Smith, Paul D; Khakpour, Nazanin; Dayicioglu, Deniz

2016-06-01

Women who have undergone prior augmentation mammoplasty represent a unique subset of breast cancer patients with several options available for breast reconstruction. We performed a single institution review of surgical outcomes of breast reconstruction performed in patients with breast cancer with prior history of subpectoral breast augmentation. Institutional review board-approved retrospective review was conducted among patients with previously mentioned criteria treated at our institution between 2000 and 2014. Reconstructions were grouped into 2 categories as follows: (1) removal of preexisting subpectoral implant during mastectomy with immediate tissue expander placement and (2) implant-sparing mastectomy followed by delayed exchange to a larger implant. We reviewed demographics, tumor features, and reconstruction outcomes of these groups. Fifty-three patients had preexisting subpectoral implants. Of the 63 breast reconstructions performed, 18 (28.6%) had immediate tissue expander placed and 45 (71.4%) had implant-sparing mastectomy followed by delayed implant exchange. The groups were comparable based on age, body mass index, cancer type, tumor grade, TNM stage at presentation, and hormonal receptor status. No significant difference was noted between tumor margins or subsequent recurrence, mastectomy specimen weight, removed implant volume, volume of implant placed during reconstruction, or time from mastectomy to final implant placement. Rates of complications were significantly higher in the tissue expander group compared to the implant-sparing mastectomy group 7 (38.9%) versus 4 (8.9%) (P = 0.005). Implant-sparing mastectomy with delayed implant exchange in patients with preexisting subpectoral implants is safe and has fewer complications compared to tissue expander placement. There was no difference noted in the final volume of implant placed, time interval for final implant placement, or tumor margins.

Development of a novel anisotropic self-inflating tissue expander: in vivo submucoperiosteal performance in the porcine hard palate.

PubMed

Swan, Marc C; Bucknall, David G; Czernuszka, Jan T; Pigott, David W; Goodacre, Timothy E E

2012-01-01

The advent of self-inflating hydrogel tissue expanders heralded a significant advance in the reconstructive potential of this technique. Their use, however, is limited by their uncontrolled isotropic (i.e., uniform in all directions) expansion. Anisotropy (i.e., directional dependence) was achieved by annealing a hydrogel copolymer of poly(methyl methacrylate-co-vinyl pyrrolidone) under a compressive load for a specified time period. The expansion ratio is dictated by the percentage of vinyl pyrrolidone content and the degree of compression. The expansion rate is modified by incorporating the polymer within a silicone membrane. The in vivo efficacy of differing prototype devices was investigated in juvenile pigs under United Kingdom Home Office Licence. The devices were implanted within a submucoperiosteal pocket in a total of six porcine palates; all were euthanized by 6 weeks after implantation. A longitudinal volumetric assessment of the expanded tissue was conducted, in addition to postmortem analysis of the bony and mucoperiosteal palatal elements. Uncoated devices caused excessive soft-tissue expansion that resulted in mucoperiosteal ulceration, thus necessitating animal euthanasia. The silicone-coated devices produced controlled soft-tissue expansion over the 6-week study period. There was a statistically significant increase in the volume of expanded soft tissue with no evidence of a significant acute inflammatory response to the implant, although peri-implant capsule formation was observed. Attenuation of the bony palatal shelf was noted. A unique anisotropic hydrogel device capable of controlled expansion has been developed that addresses a number of the shortcomings of the technology hitherto available.

Design, Manufacturing, and In Vitro Testing of a Patient-Specific Shape-Memory Expander for Nose Reconstruction With Forehead Flap Technique.

PubMed

Borghi, Alessandro; Rodgers, Will; Schievano, Silvia; Ponniah, Allan; O'Hara, Justine; Jeelani, Owase; Dunaway, David

2016-01-01

Forehead skin is widely acknowledged as a good donor site for total nasal reconstruction, thanks to its matching color, texture, and abundant vascularity. The forehead flap technique uses an axial pattern flap forehead skin to replace missing nasal tissue. To increase the amount of available tissue and reduce the size of the tissue defect after flap mobilization, tissue expanders may be used. Although this is a relatively established technique, limitations include reduced moldability of the forehead skin (which is thicker than the nasal skin), and the need for multiple sessions of expansion to achieve a sufficient yield to close the forehead.Shape-memory metals, such as nitinol, can be programmed to "remember" complex shapes. In this work, the methodology for producing a prototype of nitinol tissue expander able to mold the skin in a predetermined patient-specific skin shape is described. A realistic nose mold was manufactured using metal rapid prototyping; nitinol sheet and mesh were molded into nose-shape constructs, having hyperelastic as well as shape-memory capability. Computed tomography scanning was performed to assess the ability of the structure to regain its shape after phase transformation upon cooling within 2% of initial dimensions. The prototypes were implanted in a pig forehead to test its ability to impose a nose shape to the forehead skin.The shape-memory properties of nitinol offer the possibility of producing bespoke tissue expanders able to deliver complex, precisely designed skin envelopes. The hyperelastic properties of nitinol allow constant preprogrammed expansion forces to be generated throughout the expansion process.

A multidisciplinary protocol for planned skin-preserving delayed breast reconstruction for patients with locally advanced breast cancer requiring postmastectomy radiation therapy: 3-year follow-up.

PubMed

Kronowitz, Steven J; Lam, Candace; Terefe, Welela; Hunt, Kelly K; Kuerer, Henry M; Valero, Vicente; Lance, Samuel; Robb, Geoffrey L; Feng, Lei; Buchholz, Thomas A

2011-06-01

The authors examined the safety of a protocol for planned skin-preserving delayed breast reconstruction after postmastectomy radiotherapy with placement of a tissue expander for patients with locally advanced breast cancer (stages IIB and III). The authors compared 47 patients treated according to the protocol between December 2003 and May 2008 with 47 disease-stage-matched control patients who underwent standard delayed reconstruction after postmastectomy radiotherapy (no skin preservation or tissue expander) during the same period. Protocol-group complication rates were 21 percent for skin-preserving mastectomy and placement of the expander (stage 1), 5 percent for postmastectomy radiotherapy, 25 percent for expander reinflation after radiotherapy, and 24 percent for skin-preserving delayed reconstruction. The complication rate for standard delayed reconstruction was 38 percent. Tissue-expander loss rates were 32 percent overall, 9 percent for stage 1, 5 percent for postmastectomy radiotherapy, and 22 percent for reinflation. Wound-healing complications after reconstruction occurred in 3 percent of protocol-group and 10 percent of control-group patients. The median follow-up time for patients still alive at last follow-up was 40 months (range, 8.5 to 85.3 months). Three-year recurrence-free survival rates were 92 percent (95 percent CI, 83 to 100 percent) and 86 percent (95 percent CI, 76 to 98 percent) for the protocol and control groups, respectively (p = 0.87). In patients with locally advanced breast cancer, skin-preserving mastectomy with a deflated tissue expander on the chest wall during postmastectomy radiotherapy does not increase locoregional recurrence risk and is associated with lower complication rates of definitive reconstruction.

Expanded Flaps in Surgical Treatment of Pressure Sores: Our Experience for 25 Years.

PubMed

Di Caprio, Giovanni; Serra-Mestre, José Maria; Ziccardi, Pasquale; Scioli, Michelina; Larocca, Fabio; Nunziata, Vincenzo; Grella, Roberto; D'Andrea, Francesco

2015-11-01

Because the ischial region is the main weight-bearing area in sitting, it is one of the areas most frequently affected by pressure ulcers in paraplegic patients resuming the sitting position during the subacute and chronic stages. The techniques described to date have not been able to reduce the high rates of recurrence and flap dehiscence. Other groups have described successful tissue expansion in the treatment of pressure ulcers, but to date, the long-term results of the procedure have not been reported. The long-term follow-up of 138 reconstructions of the ischial region in patients with pressure ulcers types III to IV treated with posterior thigh expanded rotation flaps is reported. All patients achieved complete resolution, with adequate coverage of deeper layers, although 15.94% presented minor complications. None of these complications impeded full repair of the lesion. The 28 lesions that recurred were all reconstructed with the re-expansion of the same flap. There were no cases of flap dehiscence. The use of tissue expanders to treat ischial pressure ulcers, especially in patients with long life expectancy, offers important advantages over other approaches. The procedure provides abundant, high-quality tissue and may be repeated many times without creating new scars. With the use of tissue expanders, other reconstructive options can be reserved for the future.

Temporary endoscopic metallic stent for idiopathic esophageal achalasia.

PubMed

Coppola, Franco; Gaia, Silvia; Rolle, Emanuela; Recchia, Serafino

2014-02-01

Idiopathic achalasia is a motor disorder of the esophagus of unknown etiology caused by loss of motor neurons determining an altered motility. It may determine severe symptoms such as progressive dysphagia, regurgitations, and pulmonary aspirations. Many therapeutic options may be offered to patients with achalasia, from surgery to endoscopic treatments such as pneumatic dilation, botulinum injection, peroral endoscopic myotomy, or endoscopic stenting. Recently, temporary placement of a stent was proposed by Cheng as therapy for achalasia disorders, whereas no Western authors have dealt with it up to date. The present study reports our preliminary experience in 7 patients with achalasia treated with a temporary stent. Partially covered self-expanding metallic stents (Micro-Tech, Nanjin, China) 80 mm long and 30 mm wide were placed under fluoroscopic control and removed after 6 days. Clinical follow-up was scheduled to check endoscopic success, symptoms release, and complications. The placement and the removal of the stents were obtained in all patients without complications. Mean clinical follow-up was 19 months. Five out of 7 patients referred total symptoms release and 2 experienced significant improvement of dysphagia. The procedure was not time consuming and was safe; no mild or severe complications were registered. In conclusion, our results may suggest a possible safe and effective endoscopic alternative treatment in patients with achalasia; however, further larger studies are necessary to confirm these promising, but very preliminary, data.

In vitro immersion studies of optimized electrospun bioglass 45S5 fibers for tissue engineering application

NASA Astrophysics Data System (ADS)

Durgalakshmi, D.; Balakumar, S.

2015-06-01

Bioactive-glass scaffolds are crucial in bone tissue engineering application since, they work as temporary templates for tissue regrowth and provides structural support to the cells. However, many issues remain unfolded with regard to their design. In this study, for the first time bioactive glass 45S5 fibers were synthesized using electrospinning technique. The electrospinning process parameters were optimized to obtain reproducible fibers. The effect of solvent concentration and polymer concentration on fiber formation was clearly studied. In vitro studies in simulated body fluid (SBF) were performed to investigate the bioactivity and mineralization of the scaffold by inducing the formation of hydroxyapatite (HA) crystals.

Supra-plasma expanders: the future of treating blood loss and anemia without red cell transfusions?

PubMed

Tsai, Amy G; Vázquez, Beatriz Y Salazar; Hofmann, Axel; Acharya, Seetharama A; Intaglietta, Marcos

2015-01-01

Oxygen delivery capacity during profoundly anemic conditions depends on blood's oxygen-carrying capacity and cardiac output. Oxygen-carrying blood substitutes and blood transfusion augment oxygen-carrying capacity, but both have given rise to safety concerns, and their efficacy remains unresolved. Anemia decreases oxygen-carrying capacity and blood viscosity. Present studies show that correcting the decrease of blood viscosity by increasing plasma viscosity with newly developed plasma expanders significantly improves tissue perfusion. These new plasma expanders promote tissue perfusion, increasing oxygen delivery capacity without increasing blood oxygen-carrying capacity, thus treating the effects of anemia while avoiding the transfusion of blood.

Expansion in the presence of FGF-2 enhances the functional development of cartilaginous tissues engineered using infrapatellar fat pad derived MSCs.

PubMed

Buckley, C T; Kelly, D J

2012-07-01

MSCs from non-cartilaginous knee joint tissues such as the infrapatellar fat pad (IFP) and synovium possess significant chondrogenic potential and provide a readily available and clinically feasible source of chondroprogenitor cells. Fibroblast growth factor-2 (FGF-2) has been shown to be a potent mitotic stimulator during ex vivo expansion of MSCs, as well as regulating their subsequent differentiation potential. The objective of this study was to investigate the longer term effects of FGF-2 expansion on the functional development of cartilaginous tissues engineered using MSCs derived from the IFP. IFP MSCs were isolated and expanded to passage 2 in a standard media formulation with or without FGF-2 (5 ng/ml) supplementation. Expanded cells were encapsulated in agarose hydrogels, maintained in chondrogenic media for 42 days and analysed to determine their mechanical properties and biochemical composition. Culture media, collected at each feed, was also analysed for biochemical constituents. MSCs expanded in the presence of FGF-2 proliferated more rapidly, with higher cell yields and lower population doubling times. FGF-2 expanded MSCs generated the most mechanically functional tissue. Matrix accumulation was dramatically higher after 21 days for FGF-2 expanded MSCs, but decreased between day 21 and 42. By day 42, FGF-2 expanded MSCs had still accumulated ∼1.4 fold higher sGAG and ∼1.7 fold higher collagen compared to control groups. The total amount of sGAG synthesised (retained in hydrogels and released into the media) was ∼2.4 fold higher for FGF-2 expanded MSCs, with only ∼25% of the total amount generated being retained within the constructs. Further studies are required to investigate whether IFP derived MSCs have a diminished capacity to synthesise other matrix components important in the aggregation, assembly and retention of proteoglycans. In conclusion, expanding MSCs in the presence of FGF-2 rapidly accelerates chondrogenesis in 3D agarose cultures resulting in superior mechanical functionality. Copyright © 2011 Elsevier Ltd. All rights reserved.

Wound ballistics of firearm-related injuries--part 1: missile characteristics and mechanisms of soft tissue wounding.

PubMed

Stefanopoulos, P K; Filippakis, K; Soupiou, O T; Pazarakiotis, V C

2014-12-01

Firearm-related injuries are caused by a wide variety of weapons and projectiles. The kinetic energy of the penetrating projectile defines its ability to disrupt and displace tissue, whereas the actual tissue damage is determined by the mode of energy release during the projectile-tissue interaction and the particular characteristics of the tissues and organs involved. Certain projectile factors, namely shape, construction, and stability, greatly influence the rate of energy transfer to the tissues along the wound track. Two zones of tissue damage can be identified, the permanent cavity created by the passage of the bullet and a potential area of contused tissue surrounding it, produced mainly by temporary cavitation which is a manifestation of effective high-energy transfer to tissue. Due to the complex nature of these injuries, wound assessment and the type and extent of treatment required should be based on an understanding of the various mechanisms contributing to tissue damage. Copyright © 2014 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Asbestosis

MedlinePlus

Pulmonary fibrosis - from asbestos exposure; Interstitial pneumonitis - from asbestos exposure ... Breathing in asbestos fibers can cause scar tissue (fibrosis) to form inside the lung. Scarred lung tissue does not expand and ...

Temporary placement of fully covered self-expandable metal stents in benign biliary strictures.

PubMed

Ryu, Choong Heon; Kim, Myung Hwan; Lee, Sang Soo; Park, Do Hyun; Seo, Dong Wan; Lee, Sung Koo

2013-07-01

Benign biliary strictures (BBSs) have been endoscopically managed with plastic stent placement. However, data regarding fully covered self-expandable metal stents (FCSEMSs) in BBS patients remain scarce in Korea. Forty-one patients (21 men, 65.9%) with BBSs underwent FCSEMS placement between February 2007 and July 2010 in Asan Medical Center. Efficacy and safety were evaluated retrospectively. Patients were considered to have resolution if they showed evidence of stricture resolution on cholangiography and if an inflated retrieval balloon easily passed through the strictures at FCSEMS removal. The mean FCSEMS placement time was 3.2 (1.9-6.2) months. Patients were followed for a mean of 10.2 (1.0-32.0) months after FCSEMS removal. The BBS resolution rate was confirmed in 38 of 41 (92.7%) patients who underwent FCSEMS removal. After FCSEMS removal, 6 of 38 (15.8%) patients experienced symptomatic recurrent stricture and repeat stenting was performed. When a breakdown by etiology of stricture was performed, 14 of 15 (93.3%) patients with chronic pancreatitis, 17 of 19 (89.5%) with gall stone-related disease, 4 of 4 (100%) with surgical procedures, and 2 of 2 (100%) with BBSs of other etiology had resolution at FCSEMS removal. Complications related to stent therapy occurred in 12 (29%) patients, including post-ERCP pancreatitis (n=4), proximal migration (n=3), distal migration (n=3), and occlusion (n=2). Temporary FCSEMS placement in BBS patients offers a potential alternative to plastic stenting. However, because of the significant complications and modest resolution rates, the potential benefits and risks should be evaluated in further investigations.

Toward a Molecular Understanding of Noise-Induced Hearing Loss

DTIC Science & Technology

2017-10-01

cell, SAHA, Heat shock, sex differences 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON...threshold shift, Temporary threshold shift, Noise induced hearing loss, Ribotag, RNA-seq, Hair cell, Supporting cell, SAHA, Heat shock, Sex ...also sex -specific. TTS-inducing noise exposure: crosses, calibration, validation cytocochleograms, noise exposure, tissue harvesting, polysome IP

Maternal Endogenous Forces and Shoulder Dystocia.

PubMed

Grimm, Michele J

2016-12-01

Childbirth is a complicated biomechanical process that many take for granted. However, the delivery forces generated by a mother (uterine contractions and maternal pushing) are strong and have a significant effect on the body and tissues of the fetus, especially during the second stage of labor. Although most infants are born without negative, force-related outcomes, in some infants the normal forces of labor cause an injury that can have either temporary or permanent sequelae. The biomechanical situation is further complicated when an infant's shoulder impacts the maternal pelvis, which provides increased resistance and creates added stresses within the neonatal body and tissues.

Safety of endoscopic removal of self-expandable stents after treatment of benign esophageal diseases.

PubMed

van Halsema, Emo E; Wong Kee Song, Louis M; Baron, Todd H; Siersema, Peter D; Vleggaar, Frank P; Ginsberg, Gregory G; Shah, Pari M; Fleischer, David E; Ratuapli, Shiva K; Fockens, Paul; Dijkgraaf, Marcel G W; Rando, Giacomo; Repici, Alessandro; van Hooft, Jeanin E

2013-01-01

Temporary placement of self-expandable stents has been increasingly used for the management of benign esophageal diseases. To evaluate the safety of endoscopic removal of esophageal self-expandable stents placed for the treatment of benign esophageal diseases. Multicenter retrospective study. Six tertiary care centers in the United States and Europe. A total of 214 patients with benign esophageal diseases undergoing endoscopic stent removal. Endoscopic stent removal. Endoscopic techniques for stent removal, time to stent removal, and adverse events related to stent removal. A total of 214 patients underwent a total of 329 stent extractions. Stents were mainly placed for refractory strictures (49.2%) and fistulae (49.8%). Of the removed stents, 52% were fully covered self-expandable metal stents (FCSEMSs), 28.6% were partially covered self-expandable metal stents (PCSEMSs), and 19.5% were self-expandable plastic stents. A total of 35 (10.6%) procedure-related adverse events were reported, including 7 (2.1%) major adverse events. Multivariate analysis revealed that use of PCSEMSs (P < .001) was a risk factor for adverse events during stent removal. Favorable factors for successful stent removal were FCSEMSs (P ≤ .012) and stent migration (P = .010). No significant associations were found for stent indwelling time (P = .145) and stent embedding (P = .194). Retrospective analysis, only tertiary care centers. With an acceptable major adverse event rate of 2.1%, esophageal stent removal in the setting of benign disease was found to be a safe and feasible procedure. FCSEMSs were more successfully removed than self-expandable plastic stents and PCSEMSs. Adverse events caused by stent removal were not time dependent. Copyright © 2013 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

Adipose Tissue Angiogenesis: Impact on Obesity and Type-2 Diabetes

PubMed Central

Corvera, Silvia; Gealekman, Olga

2013-01-01

The growth and function of tissues is critically dependent on their vascularization. Adipose tissue is capable of expanding many-fold during adulthood, therefore requiring the formation of new vasculature to supply growing and proliferating adipocytes. The expansion of the vasculature in adipose tissue occurs through angiogenesis, where new blood vessels develop from those pre-existing within the tissue. Inappropriate angiogenesis may underlie adipose tissue dysfunction in obesity, which in turn increases type-2 diabetes risk. In addition, genetic and developmental factors involved in vascular patterning may define the size and expandability of diverse adipose tissue depots, which are also associated with type-2 diabetes risk. Moreover, the adipose tissue vasculature appears to be the niche for pre-adipocyte precursors, and factors that affect angiogenesis may directly impact the generation of new adipocytes. Here we review recent advances on the basic mechanisms of angiogenesis, and on the role of angiogenesis in adipose tissue development and obesity. A substantial amount of data point to a deficit in adipose tissue angiogenesis as a contributing factor to insulin resistance and metabolic disease in obesity. These emerging findings support the concept of the adipose tissue vasculature as a source of new targets for metabolic disease therapies. PMID:23770388

Stress distribution and displacement by different bone-borne palatal expanders with micro-implants: a three-dimensional finite-element analysis.

PubMed

Lee, Hye Kyung; Bayome, Mohamed; Ahn, Chee Soo; Kim, Seong-Hun; Kim, Ki Beom; Mo, Sung-Seo; Kook, Yoon-Ah

2014-10-01

The aim of this study was to analyze stress distribution and displacement of the maxilla and teeth according to different designs of bone-borne palatal expanders using micro-implants. A three-dimensional (3D) finite-element (FE) model of the craniofacial bones and maxillary teeth was obtained. Four designs of rapid maxillary expanders: one with micro-implants placed lateral to mid-palatal suture (type 1), the second at the palatal slope (type 2), the third as in type 1 with additional conventional Hyrax arms (type 3), and the fourth surgically assisted tooth-borne expander (type 4) were added to the FE models. Expanders were activated transversely for 0.25mm. Geometric nonlinear theory was applied to evaluate Von-Mises Stress distribution and displacement. All types exhibited downward displacement and demonstrated more horizontal movement in the posterior area. Type 3 showed the most transverse displacement. The rotational movement of dentoalveolar unit was larger in types 1 and 3, whereas it was relatively parallel in types 2 and 4. The stresses were concentrated around the micro-implants in types 1 and 3 only. Type 2 had the least stress concentrations around the anchorage and showed alveolar expansion without buccal inclination. It is recommended to apply temporary anchorage devices to the palatal slopes to support expanders for efficient treatment of maxillary transverse deficiency. © The Author 2012. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Ballistic injury.

PubMed

Fackler, M L

1986-12-01

Wound profiles made under controlled conditions in the wound ballistics laboratory at the Letterman Army Institute of Research showed the location along their tissue path at which projectiles cause tissue disruption and the type of disruption (crush from direct contact with the projectile or stretch from temporary cavitation). Comparison of wound profiles showed the fallacy in attempting to judge wound severity using velocity alone, and laid to rest the common belief that in treating a wound caused by a high-velocity missile, one needs to excise tissue far in excess of that which appears damaged. All penetrating projectile wounds, whether civilian or military, therefore should be treated the same regardless of projectile velocity. Diagnosis of the approximate amount and location of tissue disruption is made by physical examination and appropriate radiographic studies. These wounds are contaminated, and coverage with a penicillin-type antibiotic should be provided.

Development of tissue-engineered self-expandable aortic stent grafts (Bio stent grafts) using in-body tissue architecture technology in beagles.

PubMed

Kawajiri, Hidetake; Mizuno, Takeshi; Moriwaki, Takeshi; Ishibashi-Ueda, Hatsue; Yamanami, Masashi; Kanda, Keiichi; Yaku, Hitoshi; Nakayama, Yasuhide

2015-02-01

In this study, we aimed to describe the development of tissue-engineered self-expandable aortic stent grafts (Bio stent graft) using in-body tissue architecture technology in beagles and to determine its mechanical and histological properties. The preparation mold was assembled by insertion of an acryl rod (outer diameter, 8.6 mm; length, 40 mm) into a self-expanding nitinol stent (internal diameter, 9.0 mm; length, 35 mm). The molds (n = 6) were embedded into the subcutaneous pouches of three beagles for 4 weeks. After harvesting and removing each rod, the excessive fragile tissue connected around the molds was trimmed, and thus tubular autologous connective tissues with the stent were obtained for use as Bio stent grafts (outer diameter, approximately 9.3 mm in all molds). The stent strut was completely surrounded by the dense collagenous membrane (thickness, ∼150 µm). The Bio stent graft luminal surface was extremely flat and smooth. The graft wall of the Bio stent graft possessed an elastic modulus that was almost two times higher than that of the native beagle abdominal aorta. This Bio stent graft is expected to exhibit excellent biocompatibility after being implanted in the aorta, which may reduce the risk of type 1 endoleaks or migration. © 2014 Wiley Periodicals, Inc.

Outcome of 122 delayed breast reconstruction following post-mastectomy radiotherapy: The scarless latissimus dorsi flap with tissue expansion technique.

PubMed

de Runz, A; Boccara, D; Bekara, F; Chaouat, M; Mimoun, M

2017-02-01

Delayed breast reconstruction with tissue expansion may be risky after radiotherapy, due to the poor skin quality. To permit the use of the tissue expansion procedure, we propose a scarless latissimus dorsi flap to bring tissue trophicity, by a healthy vascularized muscular interface with no donor scar and no patch effect. The objective of this study is to assess the outcome of the tissue expansion technique with scarless latissimus dorsi flap after post-mastectomy radiotherapy. All the patients who had benefited of a delayed breast reconstruction after radiotherapy using tissue expansion technique with scarless latissimus dorsi flap, between January 2000 and January 2013, were reviewed. The exclusion criteria were: prior breast reconstruction, or interruption of breast reconstruction procedure due to active metastatic disease requiring ongoing oncological treatment. The complications were identified: failures of reconstruction, implant exposure, wound dehiscence, capsular contracture, deflation of implant, hematoma, infection, and skin necrosis. One hundred and twenty-two breasts were reviewed. The average time between the flap and the expander intervention was: 194±114 SD (28-1051) days. The mean volume of inserted expander was 633±111 SD (350-1100) mL and the mean inflation volume was 578±190 SD (170-1160) mL. The average time between insertion of the expander and insertion of the permanent implant was 132±76 SD (49-683) days. The mean inflation of the implant volume was 368±105 SD (130-620) mL. Forty patients developed at least one complication. The most common complication was the appearance of a capsular contracture requiring a capsulectomy: 11 (9.2%) with permanent implants and 6 (4.9%) with expander. Deflation of implants occurred with six permanent implants and with one expander. There were 3 breast reconstructions failures (two infections and one exposure of implants). This procedure offers the advantages that there is no unattractive scar, and that there are low rates of exposure or failed reconstruction. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

The use of self-inflating hydrogel expanders in pediatric patients with congenital microphthalmia in China.

PubMed

Hou, Zhijia; Yang, Qiong; Chen, Tao; Hao, Lei; Li, Yang; Li, Dongmei

2012-10-01

To report the results of enlarging orbital volume in consecutive cases of severe congenital microphthalmia by means of solid hydrophilic tissue expanders. The medical records of consecutive patients with congenital microphthalmia who underwent the placement of a hydrogel expander were retrospectively reviewed. Main outcome measures were orbital tissue expansion, prosthetic retention, and patient family satisfaction. A total of 17 patients were included in the study. All patients were able to retain an ocular prosthesis. The horizontal palpebral length increased from 71.3% of the contralateral unaffected eye to 85.4% of the contralateral unaffected eye. The expansion of orbital volume was assessed in seven patients. The volume of the microphthalmic orbits was expanded from 74.7% of the contralateral unaffected orbits to 83.5% of the contralateral unaffected orbits. Aesthetic results were satisfactory to both physicians and patient families. The following complications were noted in two patients: inferior migration of a spherical expander occurred in one case; a hemispheric expander was removed by the patient in another case. Hydrogel implants can successfully expand the dimensions of the conjunctival sac and the orbit in cases of severe congenital microphthalmia. Copyright © 2012 American Association for Pediatric Ophthalmology and Strabismus. Published by Mosby, Inc. All rights reserved.

Visualisation of the temporary cavity by computed tomography using contrast material.

PubMed

Schyma, Christian; Hagemeier, Lars; Greschus, Susanne; Schild, Hans; Madea, Burkhard

2012-01-01

The temporary cavity of a missile produces radial tears in ordnance gelatine, which correlate to the energy transfer. Computed tomography is a useful and non-destructive method to examine gelatine blocks. However, the tears give only few radiocontrast by air filling, which decreases with the time past shooting. Therefore, systematically, a radiocontrast material was searched to enhance the contrast. Different contrast materials were amalgamated to acryl paint, and about 7 g was sealed in a foil bag, which was integrated in the front of a standard 10% gelatine cylinder. Shots with Action-5 expanding bullets were performed from a 5-m distance. Gelatine was scanned by multi-slice computed tomography. The multiplanar reconstructed images were compared to mechanically cut slices of 1 cm thickness. It was shown experimentally that iodine containing water-soluble contrast material did not give sufficient contrast and caused diffusion artefacts. Best results were obtained by barium sulphate emulsion. The amount of acryl paint was sufficient to colour the tears for optical scanning. The radiocontrast of barium leads to satisfying imaging of tears and allowed the creation of a three-dimensional reconstruction of the temporary cavity. Comparison of optical and radiological results showed an excellent correlation, but absolute measures in computed tomographic (CT) images remained lower compared with optically gathered values in the gelatine slices. Combination of paint and contrast material for CT examination will facilitate the evaluation of complex ballistic models and increase accuracy.

A joint modelling approach for multistate processes subject to resolution and under intermittent observations.

PubMed

Yiu, Sean; Tom, Brian

2017-02-10

Multistate processes provide a convenient framework when interest lies in characterising the transition intensities between a set of defined states. If, however, there is an unobserved event of interest (not known if and when the event occurs), which when it occurs stops future transitions in the multistate process from occurring, then drawing inference from the joint multistate and event process can be problematic. In health studies, a particular example of this could be resolution, where a resolved patient can no longer experience any further symptoms, and this is explored here for illustration. A multistate model that includes the state space of the original multistate process but partitions the state representing absent symptoms into a latent absorbing resolved state and a temporary transient state of absent symptoms is proposed. The expanded state space explicitly distinguishes between resolved and temporary spells of absent symptoms through disjoint states and allows the uncertainty of not knowing if resolution has occurred to be easily captured when constructing the likelihood; observations of absent symptoms can be considered to be temporary or having resulted from resolution. The proposed methodology is illustrated on a psoriatic arthritis data set where the outcome of interest is a set of intermittently observed disability scores. Estimated probabilities of resolving are also obtained from the model. © 2016 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd. © 2016 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.

Polyacylurethanes as Novel Degradable Cell Carrier Materials for Tissue Engineering

PubMed Central

Jovanovic, Danijela; Roukes, Frans V.; Löber, Andrea; Engels, Gerwin E.; van Oeveren, Willem; van Seijen, Xavier J. Gallego; van Luyn, Marja J.A.; Harmsen, Martin C.; Schouten, Arend Jan

2011-01-01

Polycaprolactone (PCL) polyester and segmented aliphatic polyester urethanes based on PCL soft segment have been thoroughly investigated as biodegradable scaffolds for tissue engineering. Although proven beneficial as long term implants, these materials degrade very slowly and are therefore not suitable in applications in which scaffold support is needed for a shorter time. A recently developed class of polyacylurethanes (PAUs) is expected to fulfill such requirements. Our aim was to assess in vitro the degradation of PAUs and evaluate their suitability as temporary scaffold materials to support soft tissue repair. With both a mass loss of 2.5–3.0% and a decrease in molar mass of approx. 35% over a period of 80 days, PAUs were shown to degrade via both bulk and surface erosion mechanisms. Fourier Transform Infra Red (FTIR) spectroscopy was successfully applied to study the extent of PAUs microphase separation during in vitro degradation. The microphase separated morphology of PAU1000 (molar mass of the oligocaprolactone soft segment = 1000 g/mol) provided this polymer with mechano-physical characteristics that would render it a suitable material for constructs and devices. PAU1000 exhibited excellent haemocompatibility in vitro. In addition, PAU1000 supported both adhesion and proliferation of vascular endothelial cells and this could be further enhanced by pre-coating of PAU1000 with fibronectin (Fn). The contact angle of PAU1000 decreased both with in vitro degradation and by incubation in biological fluids. In endothelial cell culture medium the contact angle reached 60°, which is optimal for cell adhesion. Taken together, these results support the application of PAU1000 in the field of soft tissue repair as a temporary degradable scaffold. PMID:28824103

Postphloem, Nonvascular Transfer in Citrus

PubMed Central

Koch, Karen E.; Avigne, Wayne T.

1990-01-01

Postphloem, nonvascular assimilate transport occurs over an unusually long area in citrus fruit and thus facilitates investigation of this process relative to sugar entry into many sink structures. Labeled photosynthates moving into juice tissues of grapefruit (Citrus paradisi Macf.) slowed dramatically after entering the postphloem transport path (parenchyma cells, narrow portions of segment epidermis, and hair-like, parenchymatous stalks of juice sacs). Kinetic, metabolic, and compositional data indicated that transfer through the nonvascular area was delayed many hours by temporary storage and/or equilibration with sugars in compartments along the postphloem path. Labeled assimilates were generally recovered as sucrose throughout the path, and extent of hexose formation enroute bore no apparent relationship to the assimilate transfer process. Even after 24 hours, radiolabel was restricted to discrete, highly localized areas directly between vascular bundles and juice sacs. Postphloem transfer occurred against an ascending sucrose concentration gradient in young fruit, whereas a descending gradient (favoring diffusion/cytoplasmic streaming) developed only later in maturation. Involvement of a postphloem bulk flow is complicated in the present instance by the extremely limited water loss from juice sacs either via transpiration or fluid backflow. Nonetheless, tissue expansion can account for a collective water inflow of at least 1.0 milliliter per day throughout the majority of juice sac development, thus providing a modest, but potentially important means of nonvascular solution flow. Overall, data indicate postphloem transfer (a) can follow highly localized paths through sizable nonvascular areas (up to 3.0 centimeters total), (b) appears to involve temporary storage and/or equilibration with compartmentalized sugars enroute, (c) can occur either against an overall up-hill sugar gradient (young tissues) or along a descending gradient (near full expansion), and (d) appears to involve at least some contribution by nonvascular mass flow accommodated by tissue expansion. Images Figure 1 Figure 4 PMID:16667632

Multiplexed and scalable super-resolution imaging of three-dimensional protein localization in size-adjustable tissues.

PubMed

Ku, Taeyun; Swaney, Justin; Park, Jeong-Yoon; Albanese, Alexandre; Murray, Evan; Cho, Jae Hun; Park, Young-Gyun; Mangena, Vamsi; Chen, Jiapei; Chung, Kwanghun

2016-09-01

The biology of multicellular organisms is coordinated across multiple size scales, from the subnanoscale of molecules to the macroscale, tissue-wide interconnectivity of cell populations. Here we introduce a method for super-resolution imaging of the multiscale organization of intact tissues. The method, called magnified analysis of the proteome (MAP), linearly expands entire organs fourfold while preserving their overall architecture and three-dimensional proteome organization. MAP is based on the observation that preventing crosslinking within and between endogenous proteins during hydrogel-tissue hybridization allows for natural expansion upon protein denaturation and dissociation. The expanded tissue preserves its protein content, its fine subcellular details, and its organ-scale intercellular connectivity. We use off-the-shelf antibodies for multiple rounds of immunolabeling and imaging of a tissue's magnified proteome, and our experiments demonstrate a success rate of 82% (100/122 antibodies tested). We show that specimen size can be reversibly modulated to image both inter-regional connections and fine synaptic architectures in the mouse brain.

Options for Closure of the Infected Abdomen

PubMed Central

Campbell, Chris A.; Rosenberger, Laura H.; Politano, Amani D.; Davies, Stephen W.; Riccio, Lin M.; Sawyer, Robert G.

2012-01-01

Abstract Background The infected abdomen poses substantial challenges to surgeons, and often, both temporary and definitive closure techniques are required. We reviewed the options available to close the abdominal wall defect encountered frequently during and after the management of complicated intra-abdominal infections. Methods A comprehensive review was performed of the techniques and literature on abdominal closure in the setting of intra-abdominal infection. Results Temporary abdominal closure options include the Wittmann Patch, Bogota bag, vacuum-assisted closure (VAC), the AbThera™ device, and synthetic or biologic mesh. Definitive reconstruction has been described with mesh, components separation, and autologous tissue transfer. Conclusion Reconstructing the infected abdomen, both temporarily and definitively, can be accomplished with various techniques, each of which is associated with unique advantages and disadvantages. Appropriate judgment is required to optimize surgical outcomes in these complex cases. PMID:23216525

Adipose tissue expandability and the early origins of PCOS.

PubMed

de Zegher, Francis; Lopez-Bermejo, Abel; Ibáñez, Lourdes

2009-11-01

The most prevalent phenotypes of polycystic ovary syndrome (PCOS) are characterized by insulin resistance and androgen excess. The adipose tissue (AT) expandability hypothesis explains the development of insulin resistance in obesity and in cases of AT deficit. In line with this hypothesis, we propose that hyperinsulinemic androgen excess in PCOS is often underpinned by exhaustion of the capacity to expand subcutaneous AT in a metabolically safe way. Such exhaustion might occur when a positive energy imbalance meets a normal fat-storage capacity and/or when a normal energy balance faces a low fat storage capacity. This concept thus explains how PCOS phenotypes might result from obesity, prenatal growth restraint or a genetic lipodystrophy, or, experimentally, from prenatal androgen excess.

External Port Tissue Expansion in the Pediatric Population: Confirming Its Safety and Efficacy.

PubMed

Azadgoli, Beina; Fahradyan, Artur; Wolfswinkel, Erik M; Tsuha, Michaela; Magee, William; Hammoudeh, Jeffrey A; Urata, Mark M; Howell, Lori K

2018-06-01

External filling ports in tissue expander-based reconstruction have the advantages of being associated with less pain and emotional distress. However, among practicing surgeons using tissue expansion, a theoretical concern remains regarding higher risk of infection. The authors' goal was to evaluate external port safety in the pediatric population by looking at the complications and overall success rate of reconstruction. A retrospective review of all patients undergoing tissue expansion using external ports at Children's Hospital Los Angeles between January of 2008 and June of 2016 was conducted. Patient demographic and perioperative data were collected and analyzed. Two hundred forty-one expanders were placed in 100 pediatric patients, resulting in 123 procedures for congenital and acquired conditions, with an average age at the time of surgery of 7.1 years (range, 1 month to 19.9 years) and average follow-up length of 2.5 years (range, 2.8 months to 8.8 years). The overall complication rate was 29.9 percent, and the infection rate was 17 percent. The majority of these cases were treated conservatively without additional need for surgery. Of 123 cases, 25 required premature expander removal because of complications. Despite early intervention, 21 of these cases underwent successful completion of their reconstruction according to the preoperative plan, resulting in an overall 96.7 percent success rate of tissue expander reconstruction. In children, who are often less tolerant of the pain and distress associated with internal port expansion, the authors encourage the use of external ports. This study found a high success rate in terms of successful reconstruction, with the majority of complications being treated conservatively. Therapeutic, IV.

Monitoring of tissue modification with optical coherence tomography

NASA Astrophysics Data System (ADS)

Zhang, Wei; Luo, Qingming; Yao, Lei; Cheng, Haiying; Zeng, Shaoqun

2002-04-01

An experimental monitoring of tissue modification of in vitro and in vivo rabbit dura mater with administration of osmotical agents, 40% glucose solution and glycerol, using optical coherence tomography was presented. The preliminary results of experimental study of influence of osmotical liquids (glucose solutions, glycerol) of rabbit dura mater were reported. The significant decreasing of the light from surface and increasing of the light from the deep of dura mater under action of osmotical solutions and the increasing of OCT imaging depth were demonstrated. Experiments showed that administration of osmolytes to dura mater allowed for effective and temporary control of its optical characteristics, which made dura mater more transparent, increased the ability of light penetrating the tissue, and consequently improved the optical imaging depth. It is a significant study, which can improve penetration of optical imaging of cerebral function and acquire more information of the deep brain tissue.

Ballistics and anatomical modelling - A review.

PubMed

Humphrey, Caitlin; Kumaratilake, Jaliya

2016-11-01

Ballistics is the study of a projectiles motion and can be broken down into four stages: internal, intermediate, external and terminal ballistics. The study of the effects a projectile has on a living tissue is referred to as wound ballistics and falls within terminal ballistics. To understand the effects a projectile has on living tissues the mechanisms of wounding need to be understood. These include the permanent and temporary cavities, energy, yawing, tumbling and fragmenting. Much ballistics research has been conducted including using cadavers, animal models and simulants such as ballistics ordnance gelatine. Further research is being conducted into developing anatomical, 3D, experimental and computational models. However, these models need to accurately represent the human body and its heterogeneous nature which involves understanding the biomechanical properties of the different tissues and organs. Further research is needed to accurately represent the human tissues with simulants and is slowly being conducted. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Rapid Engineering of Three-Dimensional, Multicellular Tissues With Polymeric Scaffolds

NASA Technical Reports Server (NTRS)

Gonda, Steve R.; Jordan, Jacqueline; Fraga, Denise N.

2007-01-01

A process has been developed for the rapid tissue engineering of multicellular-tissue-equivalent assemblies by the controlled enzymatic degradation of polymeric beads in a low-fluid-shear bioreactor. In this process, the porous polymeric beads serve as temporary scaffolds to support the assemblies of cells in a tissuelike 3D configuration during the critical initial growth phases of attachment of anchorage-dependent cells, aggregation of the cells, and formation of a 3D extracellular matrix. Once the cells are assembled into a 3D array and enmeshed in a structural supportive 3D extracellular matrix (ECM), the polymeric scaffolds can be degraded in the low-fluid-shear environment of the NASA-designed bioreactor. The natural 3D tissuelike assembly, devoid of any artificial support structure, is maintained in the low-shear bioreactor environment by the newly formed natural cellular/ECM. The elimination of the artificial scaffold allows normal tissue structure and function.

Electroporation-based technologies for medicine: principles, applications, and challenges.

PubMed

Yarmush, Martin L; Golberg, Alexander; Serša, Gregor; Kotnik, Tadej; Miklavčič, Damijan

2014-07-11

When high-amplitude, short-duration pulsed electric fields are applied to cells and tissues, the permeability of the cell membranes and tissue is increased. This increase in permeability is currently explained by the temporary appearance of aqueous pores within the cell membrane, a phenomenon termed electroporation. During the past four decades, advances in fundamental and experimental electroporation research have allowed for the translation of electroporation-based technologies to the clinic. In this review, we describe the theory and current applications of electroporation in medicine and then discuss current challenges in electroporation research and barriers to a more extensive spread of these clinical applications.

Phytophthora ramorum tissue colonization studied with fluorescense microscopy

Treesearch

M. Riedel; S. Wagner; M. Gotz; L. Belbahri; F. Lefort; S. Werres

2009-01-01

The proceeding worldwide spread and the expanding host spectrum of P. ramorum has become a serious threat to natural plant communities. To encounter this threat detailed knowledge about infection pathways and tissue colonization is essential. To analyze these issues, histological studies of infected tissue with epifluorescence microscopy have been...

Effective treatment of benign biliary strictures with a removable, fully covered, self-expandable metal stent: A prospective, multicenter European study

PubMed Central

Schmidt, Arthur; Pickartz, Tilman; Lerch, Markus M; Fanelli, Fabrizio; Fiocca, Fausto; Lucatelli, Pierleone; Cereatti, Fabrizio; Hoffmeister, Albrecht; van Steenbergen, Werner; Kraft, Matthias; Meier, Benjamin

2016-01-01

Background Temporary placement of removable, fully covered, self-expandable metal stents (fcSEMS) for treatment of benign biliary strictures (BBS) has been reported to be effective. However, the optimal extraction time point remains unclear and stent migration has been a major concern. Objective The objective of this study was to evaluate the efficacy and safety of this treatment modality using an fcSEMS with a special antimigration design and prolonged stent indwell time. Methods We performed a prospective, single-arm study at six tertiary care centers in Europe. Patients with BBS underwent endoscopic or percutaneous implantation of an fcSEMS (GORE® VIABIL® Biliary Endoprosthesis, W.L. Gore & Associates, Flagstaff, AZ, USA). The devices were scheduled to be removed nine months later, and patients were to return for follow-up for an additional 15 months. Results Forty-three patients were enrolled in the study. Stricture etiology was chronic pancreatitis in the majority of patients (57.5%). All fcSEMS were placed successfully, either endoscopically (76.7%) or percutaneously (23.3%). Stent migration was observed in two patients (5.2%). Primary patency of the SEMS prior to removal was 73.0%. All attempted stent removals were successful. At removal, stricture was resolved or significantly improved without need for further therapy in 78.9% of patients. Stricture recurrence during a follow-up of two years post-implant was observed in two patients. Conclusions Temporary placement of the fcSEMS is a feasible, safe and effective treatment for BBS. The design of the device used in this study accounts for very low migration rates and facilitates easy stent retrieval, even after it has been in place for up to 11 months. PMID:28507752

Effective treatment of benign biliary strictures with a removable, fully covered, self-expandable metal stent: A prospective, multicenter European study.

PubMed

Schmidt, Arthur; Pickartz, Tilman; Lerch, Markus M; Fanelli, Fabrizio; Fiocca, Fausto; Lucatelli, Pierleone; Cereatti, Fabrizio; Hoffmeister, Albrecht; van Steenbergen, Werner; Kraft, Matthias; Meier, Benjamin; Caca, Karel

2017-04-01

Temporary placement of removable, fully covered, self-expandable metal stents (fcSEMS) for treatment of benign biliary strictures (BBS) has been reported to be effective. However, the optimal extraction time point remains unclear and stent migration has been a major concern. The objective of this study was to evaluate the efficacy and safety of this treatment modality using an fcSEMS with a special antimigration design and prolonged stent indwell time. We performed a prospective, single-arm study at six tertiary care centers in Europe. Patients with BBS underwent endoscopic or percutaneous implantation of an fcSEMS (GORE® VIABIL® Biliary Endoprosthesis, W.L. Gore & Associates, Flagstaff, AZ, USA). The devices were scheduled to be removed nine months later, and patients were to return for follow-up for an additional 15 months. Forty-three patients were enrolled in the study. Stricture etiology was chronic pancreatitis in the majority of patients (57.5%). All fcSEMS were placed successfully, either endoscopically (76.7%) or percutaneously (23.3%). Stent migration was observed in two patients (5.2%). Primary patency of the SEMS prior to removal was 73.0%. All attempted stent removals were successful. At removal, stricture was resolved or significantly improved without need for further therapy in 78.9% of patients. Stricture recurrence during a follow-up of two years post-implant was observed in two patients. Temporary placement of the fcSEMS is a feasible, safe and effective treatment for BBS. The design of the device used in this study accounts for very low migration rates and facilitates easy stent retrieval, even after it has been in place for up to 11 months.

Open-Ended Coaxial Probe Technique for Dielectric Measurement of Biological Tissues: Challenges and Common Practices.

PubMed

La Gioia, Alessandra; Porter, Emily; Merunka, Ilja; Shahzad, Atif; Salahuddin, Saqib; Jones, Marggie; O'Halloran, Martin

2018-06-05

Electromagnetic (EM) medical technologies are rapidly expanding worldwide for both diagnostics and therapeutics. As these technologies are low-cost and minimally invasive, they have been the focus of significant research efforts in recent years. Such technologies are often based on the assumption that there is a contrast in the dielectric properties of different tissue types or that the properties of particular tissues fall within a defined range. Thus, accurate knowledge of the dielectric properties of biological tissues is fundamental to EM medical technologies. Over the past decades, numerous studies were conducted to expand the dielectric repository of biological tissues. However, dielectric data is not yet available for every tissue type and at every temperature and frequency. For this reason, dielectric measurements may be performed by researchers who are not specialists in the acquisition of tissue dielectric properties. To this end, this paper reviews the tissue dielectric measurement process performed with an open-ended coaxial probe. Given the high number of factors, including equipment- and tissue-related confounders, that can increase the measurement uncertainty or introduce errors into the tissue dielectric data, this work discusses each step of the coaxial probe measurement procedure, highlighting common practices, challenges, and techniques for controlling and compensating for confounders.

Temporary Losses of Highway Capacity and Impacts on Performance: Phase 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chin, S.M.

2004-11-10

Traffic congestion and its impacts significantly affect the nation's economic performance and the public's quality of life. In most urban areas, travel demand routinely exceeds highway capacity during peak periods. In addition, events such as crashes, vehicle breakdowns, work zones, adverse weather, railroad crossings, large trucks loading/unloading in urban areas, and other factors such as toll collection facilities and sub-optimal signal timing cause temporary capacity losses, often worsening the conditions on already congested highway networks. The impacts of these temporary capacity losses include delay, reduced mobility, and reduced reliability of the highway system. They can also cause drivers to re-routemore » or reschedule trips. Such information is vital to formulating sound public policies for the highway infrastructure and its operation. In response to this need, Oak Ridge National Laboratory, sponsored by the Federal Highway Administration (FHWA), made an initial attempt to provide nationwide estimates of the capacity losses and delay caused by temporary capacity-reducing events (Chin et al. 2002). This study, called the Temporary Loss of Capacity (TLC) study, estimated capacity loss and delay on freeways and principal arterials resulting from fatal and non-fatal crashes, vehicle breakdowns, and adverse weather, including snow, ice, and fog. In addition, it estimated capacity loss and delay caused by sub-optimal signal timing at intersections on principal arterials. It also included rough estimates of capacity loss and delay on Interstates due to highway construction and maintenance work zones. Capacity loss and delay were estimated for calendar year 1999, except for work zone estimates, which were estimated for May 2001 to May 2002 due to data availability limitations. Prior to the first phase of this study, which was completed in May of 2002, no nationwide estimates of temporary losses of highway capacity by type of capacity-reducing event had been made. This report describes the second phase of the TLC study (TLC2). TLC2 improves upon the first study by expanding the scope to include delays from rain, toll collection facilities, railroad crossings, and commercial truck pickup and delivery (PUD) activities in urban areas. It includes estimates of work zone capacity loss and delay for all freeways and principal arterials, rather than for Interstates only. It also includes improved estimates of delays caused by fog, snow, and ice, which are based on data not available during the initial phase of the study. Finally, computational errors involving crash and breakdown delay in the original TLC report are corrected.« less

Design of tissue engineering scaffolds based on hyperbolic surfaces: structural numerical evaluation.

PubMed

Almeida, Henrique A; Bártolo, Paulo J

2014-08-01

Tissue engineering represents a new field aiming at developing biological substitutes to restore, maintain, or improve tissue functions. In this approach, scaffolds provide a temporary mechanical and vascular support for tissue regeneration while tissue in-growth is being formed. These scaffolds must be biocompatible, biodegradable, with appropriate porosity, pore structure and distribution, and optimal vascularization with both surface and structural compatibility. The challenge is to establish a proper balance between porosity and mechanical performance of scaffolds. This work investigates the use of two different types of triple periodic minimal surfaces, Schwarz and Schoen, in order to design better biomimetic scaffolds with high surface-to-volume ratio, high porosity and good mechanical properties. The mechanical behaviour of these structures is assessed through the finite element method software Abaqus. The effect of two parametric parameters (thickness and surface radius) is also evaluated regarding its porosity and mechanical behaviour. Copyright © 2014 IPEM. Published by Elsevier Ltd. All rights reserved.

Biomechanics and mechanobiology in functional tissue engineering

PubMed Central

Guilak, Farshid; Butler, David L.; Goldstein, Steven A.; Baaijens, Frank P.T.

2014-01-01

The field of tissue engineering continues to expand and mature, and several products are now in clinical use, with numerous other preclinical and clinical studies underway. However, specific challenges still remain in the repair or regeneration of tissues that serve a predominantly biomechanical function. Furthermore, it is now clear that mechanobiological interactions between cells and scaffolds can critically influence cell behavior, even in tissues and organs that do not serve an overt biomechanical role. Over the past decade, the field of “functional tissue engineering” has grown as a subfield of tissue engineering to address the challenges and questions on the role of biomechanics and mechanobiology in tissue engineering. Originally posed as a set of principles and guidelines for engineering of load-bearing tissues, functional tissue engineering has grown to encompass several related areas that have proven to have important implications for tissue repair and regeneration. These topics include measurement and modeling of the in vivo biomechanical environment; quantitative analysis of the mechanical properties of native tissues, scaffolds, and repair tissues; development of rationale criteria for the design and assessment of engineered tissues; investigation of the effects biomechanical factors on native and repair tissues, in vivo and in vitro; and development and application of computational models of tissue growth and remodeling. Here we further expand this paradigm and provide examples of the numerous advances in the field over the past decade. Consideration of these principles in the design process will hopefully improve the safety, efficacy, and overall success of engineered tissue replacements. PMID:24818797

Chronic Expanding Hematoma in the Extremities: A Clinical Problem of Adhesion to the Surrounding Tissues

PubMed Central

Okamoto, Takeshi; Matsuda, Shuichi

2017-01-01

Chronic expanding hematoma is characterized by continuous growth of a blood collection. We analyzed the clinical features of 7 patients with chronic expanding hematomas in the extremities, with an average age of 65.6 years. All lesions occurred in the lower extremities, with 4 seen in the thigh and 3 in the knee region. Six patients had subcutaneous hematomas, while 1 was deep-seated in the thigh. The magnetic resonance features of the lesion were compatible with those of a standard hematoma. A low signal intensity on T1- and T2-weighted imaging at the pseudocapsule was also characteristic. Cystic features were seen in 5 of 7 patients. All lesions were resected together with their pseudocapsule. In the subcutaneous lesions, it was necessary to resect adherent fascia, with or without involved skin. In the deep-seated thigh lesion, the common peroneal nerve was completely adherent to the pseudocapsule, a phenomenon from absence of the common peroneal nerve which appeared after resection. Chronic expanding hematomas of the extremities are predominantly located in the subcutaneous tissue of the lower extremity. The surrounding pseudocapsule is adherent to the adjacent tissues, and clinicians must be aware of this, especially when resecting a deep-seated lesion. PMID:28642872

Prefabricated neck expanded skin flap with the superficial temporal vessels for facial resurfacing.

PubMed

Lazzeri, Davide; Su, Weijie; Qian, Yunliang; Messmer, Caroline; Agostini, Tommaso; Spinelli, Giuseppe; Marcus, Jeffrey R; Levin, L Scott; Zenn, Micheal R; Zhang, Yi Xin

2013-05-01

The achievement of a normal-appearing face after surgical resurfacing remains an elusive goal. This is due in part to insufficient color matching, restoration of contours, and the persistence of visible scars. Flap prefabrication is a staged procedure that provides an independent axial blood supply to local expanded tissues. We describe a new reconstructive alternative with superior reconstructive surgical options for facial resurfacing that better matches damaged or discarded facial tissues. A superficial temporal fascial flap was harvested as the vascular supply of the prefabricated neck flap and located in a subcutaneous neck pocket over a tissue expander. After a 5-month period for expansion and maturation, the prefabricated skin flap was raised, islanded, and rotated to resurface the facial defect. Four patients with hemifacial postburn contracture and two patients affected by hemifacial vascular malformations aged 17 to 42 years (mean 29 years) were successfully treated with no major complication after a mean period of 15 months. Prefabricated neck-expanded skin flap demonstrated an excellent color and texture match with facial skin that surrounded the repair sites, and optimal aesthetic results were obtained. Importantly, facial expression was completely maintained due to thinness and pliability of the rotated skin. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Growth of human breast tissues from patient cells in 3D hydrogel scaffolds.

PubMed

Sokol, Ethan S; Miller, Daniel H; Breggia, Anne; Spencer, Kevin C; Arendt, Lisa M; Gupta, Piyush B

2016-03-01

Three-dimensional (3D) cultures have proven invaluable for expanding human tissues for basic research and clinical applications. In both contexts, 3D cultures are most useful when they (1) support the outgrowth of tissues from primary human cells that have not been immortalized through extensive culture or viral infection and (2) include defined, physiologically relevant components. Here we describe a 3D culture system with both of these properties that stimulates the outgrowth of morphologically complex and hormone-responsive mammary tissues from primary human breast epithelial cells. Primary human breast epithelial cells isolated from patient reduction mammoplasty tissues were seeded into 3D hydrogels. The hydrogel scaffolds were composed of extracellular proteins and carbohydrates present in human breast tissue and were cultured in serum-free medium containing only defined components. The physical properties of these hydrogels were determined using atomic force microscopy. Tissue growth was monitored over time using bright-field and fluorescence microscopy, and maturation was assessed using morphological metrics and by immunostaining for markers of stem cells and differentiated cell types. The hydrogel tissues were also studied by fabricating physical models from confocal images using a 3D printer. When seeded into these 3D hydrogels, primary human breast epithelial cells rapidly self-organized in the absence of stromal cells and within 2 weeks expanded to form mature mammary tissues. The mature tissues contained luminal, basal, and stem cells in the correct topological orientation and also exhibited the complex ductal and lobular morphologies observed in the human breast. The expanded tissues became hollow when treated with estrogen and progesterone, and with the further addition of prolactin produced lipid droplets, indicating that they were responding to hormones. Ductal branching was initiated by clusters of cells expressing putative mammary stem cell markers, which subsequently localized to the leading edges of the tissue outgrowths. Ductal elongation was preceded by leader cells that protruded from the tips of ducts and engaged with the extracellular matrix. These 3D hydrogel scaffolds support the growth of complex mammary tissues from primary patient-derived cells. We anticipate that this culture system will empower future studies of human mammary gland development and biology.

Does the presence of an implant including expander with internal port alter radiation dose? An ex vivo model.

PubMed

Strang, Barbara; Murphy, Kyla; Seal, Shane; Cin, Arianna Dal

2013-01-01

There is a lack of literature examining the dosimetric implications of irradiating breast implants and expanders with internal ports inserted at the time of mastectomy. To determine whether the presence of breast expanders with port in saline or silicone implants affect the dose uniformity across the breast when irradiated with various photon and electron energies. One tissue-equivalent torso phantom with overlying tissue expanders in saline or silicone implants were irradiated using tangential fields with 6 MV and 18 MV photons and 9 MeV and 12 MeV electrons. All dose measurements were performed using thermoluminescent dosimeters (TLDs). The TLDs were arranged around the port and the perimeters of either the expander, or saline or silicone implant. Comparisons of measured radiation doses, and between the expected and measured doses of radiation from the TLDs on each prosthesis, were performed. Data were analyzed using two-tailed t tests. There were no differences in TLD measurements between the expander and the saline implant for all energy modalities, and for the expected versus actual measurements for the saline implant. Higher than anticipated measurements were recorded for a significant number of TLD positions around the silicone implants. Radiation doses around saline implants or expanders with internal port were unaltered, whereas dose recordings for silicone implants were higher than predicted in the present laboratory/ex vivo study.

Towards a Molecular Understanding of Noise-Induced Hearing Loss

DTIC Science & Technology

2016-10-01

gene expression following different types of noise exposure and their treatments, in the inner ear. To this end, we have (a) Established the hair ...in hair cells, support cells and whole inner ears, 6 and 24 hours after noise exposure; (c) Collected and processed most of the tissue for TTS...SUBJECT TERMS Permanent threshold shift, Temporary threshold shift, Noise induced hearing loss, Ribotag, RNA-seq, hair cell, supporting cell, SAHA

Synoviocyte Derived-Extracellular Matrix Enhances Human Articular Chondrocyte Proliferation and Maintains Re-Differentiation Capacity at Both Low and Atmospheric Oxygen Tensions

PubMed Central

Kean, Thomas J.; Dennis, James E.

2015-01-01

Background Current tissue engineering methods are insufficient for total joint resurfacing, and chondrocytes undergo de-differentiation when expanded on tissue culture plastic. De-differentiated chondrocytes show poor re-differentiation in culture, giving reduced glycosaminoglycan (GAG) and collagen matrix accumulation. To address this, porcine synoviocyte-derived extracellular matrix and low (5%) oxygen tension were assessed for their ability to enhance human articular chondrocyte expansion and maintain re-differentiation potential. Methods Porcine synoviocyte matrices were devitalized using 3 non-detergent methods. These devitalized synoviocyte matrices were compared against tissue culture plastic for their ability to support human chondrocyte expansion. Expansion was further compared at both low (5%), and atmospheric (20%) oxygen tension on all surfaces. Expanded cells then underwent chondrogenic re-differentiation in aggregate culture at both low and atmospheric oxygen tension. Aggregates were assessed for their GAG and collagen content both biochemically and histologically. Results Human chondrocytes expanded twice as fast on devitalized synoviocyte matrix vs. tissue culture plastic, and cells retained their re-differentiation capacity for twice the number of population doublings. There was no significant difference in growth rate between low and atmospheric oxygen tension. There was significantly less collagen type I, collagen type II, aggrecan and more MMP13 expression in cells expanded on synoviocyte matrix vs. tissue culture plastic. There were also significant effects due to oxygen tension on gene expression, wherein there was greater collagen type I, collagen type II, SOX9 and less MMP13 expression on tissue culture plastic compared to synoviocyte matrix. There was a significant increase in GAG, but not collagen, accumulation in chondrocyte aggregates re-differentiated at low oxygen tension over that achieved in atmospheric oxygen conditions. Conclusions Synoviocyte-derived matrix supports enhanced expansion of human chondrocytes such that the chondrocytes are maintained in a state from which they can re-differentiate into a cartilage phenotype after significantly more population doublings. Also, low oxygen tension supports GAG, but not collagen, accumulation. These findings are a step towards the production of a more functional, tissue engineered cartilage. PMID:26075742

High developmental potential in vitro and in vivo of cattle embryos cloned without micromanipulators

PubMed Central

Rodríguez, Lleretny; Navarrete, Felipe I.; Tovar, Heribelt; Cox, José F.

2008-01-01

Purpose In order to simplify cloning, a new method that does not require micromanipulators was used. We aimed to evaluate the developmental potential of two bovine cell lines upon cloning. Materials and methods In vitro matured bovine oocytes, were released from zona pellucida, enucleated, fused to foetal or adult somatic donor cells. The reconstructed embryos were reprogrammed, activated and cultured until blastocyst stage. No micromanipulators were used. Blastocyst rate and quality was scored. Some expanded (d7) blastocysts were transferred to recipient cattle and collected back at d17 to assess elongation. Results High developmental potential in vitro of cloned embryos to expanded (d7) blastocysts was achieved (52.6%). In one cell line, 65.7% of blastocysts was scored. Most blastocysts (87.4%) were graded as excellent. In vivo development to elongation (day-17) in temporary recipient cows also showed a high developmental potential (11/18 transferred blastocysts elongated). Conclusions Hand-made cloning is an efficient alternative for cloning in cattle. PMID:18205035

A Theory for Self-consistent Acceleration of Energetic Charged Particles by Dynamic Small-scale Flux Ropes

NASA Astrophysics Data System (ADS)

le Roux, J. A.; Zank, G. P.; Khabarova, O.; Webb, G. M.

2016-12-01

Simulations of charged particle acceleration in turbulent plasma regions with numerous small-scale contracting and merging (reconnecting) magnetic islands/flux ropes emphasize the key role of temporary particle trapping in these structures for efficient acceleration that can result in power-law spectra. In response, a comprehensive kinetic transport theory framework was developed by Zank et al. and le Roux et al. to capture the essential physics of energetic particle acceleration in solar wind regions containing numerous dynamic small-scale flux ropes. Examples of test particle solutions exhibiting hard power-law spectra for energetic particles were presented in recent publications by both Zank et al. and le Roux et al.. However, the considerable pressure in the accelerated particles suggests the need for expanding the kinetic transport theory to enable a self-consistent description of energy exchange between energetic particles and small-scale flux ropes. We plan to present the equations of an expanded kinetic transport theory framework that will enable such a self-consistent description.

Tissue engineering and regenerative medicine: recent innovations and the transition to translation.

PubMed

Fisher, Matthew B; Mauck, Robert L

2013-02-01

The field of tissue engineering and regenerative medicine (TERM) has exploded in the last decade. In this Year (or so) in Review, we highlight some of the high impact advances within the field over the past several years. Using the past as our guide and starting with an objective premise, we attempt so to identify recent "hot topics" and transformative publications within the field. Through this process, several key themes emerged: (1) tissue engineering: grafts and materials, (2) regenerative medicine: scaffolds and factors that control endogenous tissue formation, (3) clinical trials, and (4) novel cell sources: induced pluripotent stem cells. Within these focus areas, we summarize the highly impactful articles that emerged from our objective analysis and review additional recent publications to augment and expand upon these key themes. Finally, we discuss where the TERM field may be headed and how to monitor such a broad-based and ever-expanding community.

Tissue Engineering and Regenerative Medicine: Recent Innovations and the Transition to Translation

PubMed Central

Fisher, Matthew B.

2013-01-01

The field of tissue engineering and regenerative medicine (TERM) has exploded in the last decade. In this Year (or so) in Review, we highlight some of the high impact advances within the field over the past several years. Using the past as our guide and starting with an objective premise, we attempt so to identify recent “hot topics” and transformative publications within the field. Through this process, several key themes emerged: (1) tissue engineering: grafts and materials, (2) regenerative medicine: scaffolds and factors that control endogenous tissue formation, (3) clinical trials, and (4) novel cell sources: induced pluripotent stem cells. Within these focus areas, we summarize the highly impactful articles that emerged from our objective analysis and review additional recent publications to augment and expand upon these key themes. Finally, we discuss where the TERM field may be headed and how to monitor such a broad-based and ever-expanding community. PMID:23253031

Evaluation of an integrated orbital tissue expander in congenital anophthalmos: report of preliminary clinical experience.

PubMed

Tse, David T; Abdulhafez, Mohammad; Orozco, Marcia A; Tse, Jeffrey D; Azab, Amr Osama; Pinchuk, Leonard

2011-03-01

To evaluate the effectiveness of an orbital tissue expander designed to stimulate orbital bone growth in an anophthalmic socket. Retrospective, noncomparative, interventional case series. Institutional. Nine consecutive patients with unilateral congenital anophthalmos. The orbital tissue expander is made of an inflatable silicone globe sliding on a titanium T-plate secured to the lateral orbital rim with screws. The globe is inflated by a transconjunctival injection of normal saline through a 30-gauge needle to a final volume of approximately 5 cm(3). Computed tomography scans were used to determine the orbital volume. The data studied were: demographics, prior orbital expansion procedures, secondary interventions, orbital symmetry, and implant-related complications. The primary outcome measure was the orbital volume change, and the secondary outcome measures were changes in forehead, brow, and zygomatic eminence contour and adverse events. The average patient age at implantation was 41.89 ± 39.42 months (range, 9 to 108 months). The initial average volume of inflation was 3.00 ± 0.87 cm(3) (range, 2.0 to 4.0 cm(3)), and the average final volume of 4.33 ± 0.50 cm(3) (range, 4.0 to 5.0 cm(3)) was achieved. The duration of expansion was 18.89 ± 8.80 months (range, 4 to 26 months). All patients demonstrated an average increase in the orbital tissue expander implanted orbital volume of 5.112 ± 2.173 cm(3) (range, 2.81 to 10.38 cm(3)). The average difference between the volume of the implanted and the initial contralateral orbit was 5.68 ± 2.34 cm(3), which decreased to 2.53 ± 1.80 cm(3) at the final measurement (P < .001, paired t test). All implants remained inflated except for 2 iatrogenic punctures at the second inflation and 1 that was the result of implant failure. All were replaced. The integrated orbital tissue expander is safe and effective in stimulating anophthalmic socket bone growth. Copyright © 2011 Elsevier Inc. All rights reserved.

Designing the ideal model for assessment of wound contamination after gunshot injuries: a comparative experimental study

PubMed Central

2012-01-01

Background Modern high-velocity projectiles produce temporary cavities and can thus cause extensive tissue destruction along the bullet path. It is still unclear whether gelatin blocks, which are used as a well-accepted tissue simulant, allow the effects of projectiles to be adequately investigated and how these effects are influenced by caliber size. Method Barium titanate particles were distributed throughout a test chamber for an assessment of wound contamination. We fired .22-caliber Magnum bullets first into gelatin blocks and then into porcine hind limbs placed behind the chamber. Two other types of bullets (.222-caliber bullets and 6.5 × 57 mm cartridges) were then shot into porcine hind limbs. Permanent and temporary wound cavities as well as the spatial distribution of barium titanate particles in relation to the bullet path were evaluated radiologically. Results A comparison of the gelatin blocks and hind limbs showed significant differences (p < 0.05) in the mean results for all parameters. There were significant differences between the bullets of different calibers in the depth to which barium titanate particles penetrated the porcine hind limbs. Almost no particles, however, were found at a penetration depth of 10 cm or more. By contrast, gas cavities were detected along the entire bullet path. Conclusion Gelatin is only of limited value for evaluating the path of high-velocity projectiles and the contamination of wounds by exogenous particles. There is a direct relationship between the presence of gas cavities in the tissue along the bullet path and caliber size. These cavities, however, are only mildly contaminated by exogenous particles. PMID:22490236

The gene expression profile of non-cultured, highly purified human adipose tissue pericytes: Transcriptomic evidence that pericytes are stem cells in human adipose tissue

DOE Office of Scientific and Technical Information (OSTI.GOV)

Silva Meirelles, Lindolfo da, E-mail: lindolfomeirelles@gmail.com; Laboratory for Stem Cells and Tissue Engineering, PPGBioSaúde, Lutheran University of Brazil, Av. Farroupilha 8001, 92425-900 Canoas, RS; Deus Wagatsuma, Virgínia Mara de

Pericytes (PCs) are a subset of perivascular cells that can give rise to mesenchymal stromal cells (MSCs) when culture-expanded, and are postulated to give rise to MSC-like cells during tissue repair in vivo. PCs have been suggested to behave as stem cells (SCs) in situ in animal models, although evidence for this role in humans is lacking. Here, we analyzed the transcriptomes of highly purified, non-cultured adipose tissue (AT)-derived PCs (ATPCs) to detect gene expression changes that occur as they acquire MSC characteristics in vitro, and evaluated the hypothesis that human ATPCs exhibit a gene expression profile compatible with anmore » AT SC phenotype. The results showed ATPCs are non-proliferative and express genes characteristic not only of PCs, but also of AT stem/progenitor cells. Additional analyses defined a gene expression signature for ATPCs, and revealed putative novel ATPC markers. Almost all AT stem/progenitor cell genes differentially expressed by ATPCs were not expressed by ATMSCs or culture-expanded ATPCs. Genes expressed by ATMSCs but not by ATPCs were also identified. These findings strengthen the hypothesis that PCs are SCs in vascularized tissues, highlight gene expression changes they undergo as they assume an MSC phenotype, and provide new insights into PC biology. - Highlights: • Non-cultured adipose tissue-derived human pericytes (ncATPCs) exhibit a distinctive gene expression signature. • ncATPCs express key adipose tissue stem cell genes previously described in vivo in mice. • ncATPCs express message for anti-proliferative and antiangiogenic molecules. • Most ncATPC-specific transcripts are absent in culture-expanded pericytes or ATMSCs • Gene expression changes ncATPCs undergo as they acquire a cultured ATMSC phenotype are pointed out.« less

Intraoperative Nerve Blocks Fail to Improve Quality of Recovery after Tissue Expander Breast Reconstruction: A Prospective, Double-Blinded, Randomized, Placebo-Controlled Clinical Trial.

PubMed

Lanier, Steven T; Lewis, Kevin C; Kendall, Mark C; Vieira, Brittany L; De Oliveira, Gildasio; Nader, Anthony; Kim, John Y S; Alghoul, Mohammed

2018-03-01

The authors' study represents the first level I evidence to assess whether intraoperative nerve blocks improve the quality of recovery from immediate tissue expander/implant breast reconstruction. A prospective, randomized, double-blinded, placebo-controlled clinical trial was conducted in which patients undergoing immediate tissue expander/implant breast reconstruction were randomized to either (1) intraoperative intercostal and pectoral nerve blocks with 0.25% bupivacaine with 1:200,000 epinephrine and 4 mg of dexamethasone or (2) sham nerve blocks with normal saline. The 40-item Quality of Recovery score, pain score, and opioid use in the postoperative period were compared statistically between groups. Power analysis ensured 80 percent power to detect a 10-point (clinically significant) difference in the 40-item Quality of Recovery score. Forty-seven patients were enrolled. Age, body mass index, laterality, mastectomy type, and lymph node dissection were similar between groups. There were no statistical differences in quality of recovery, pain burden as measured by visual analogue scale, opioid consumption, antiemetic use, or length of hospital stay between groups at 24 hours after surgery. Mean global 40-item Quality of Recovery scores were 169 (range, 155 to 182) for the treatment arm and 165 (range, 143 to 179) for the placebo arm (p = 0.36), indicating a high quality of recovery in both groups. Although intraoperative nerve blocks can be a safe adjunct to a comprehensive postsurgical recovery regimen, the authors' results indicate no effect on overall quality of recovery from tissue expander/implant breast reconstruction. Therapeutic, I.

Cleft palate repair with the use of osmotic expanders: a preliminary report.

PubMed

Kobus, Kazimierz F

2007-01-01

A new method of cleft palate repair by expansion of tissue by means of osmotic expanders implanted in the first stage of treatment is described. Self-expanding expanders manufactured by OSMED (Ilmenau, Germany) were implanted under the mucoperiosteal layer of the hard palate, on purpose to generate more tissue and provide facility for palate repair performed 24-48h later. Nineteen children aged from 2 to 3 years were operated from January 2004 to 15 April 2005. In clefts<10mm, tissue repair was possible without relaxing incisions. In 11 patients with clefts>10mm, cleft palate repair was more difficult and the outcomes were less favourable. Despite more generous dissection of the neurovascular bundles and other adjunctive measures such as mucosal V-Y plasty [Bardach J, Salyer K. Surgical techniques in cleft lip and palate. Chicago, London: Year Book Medical Publishers, Inc.; 1987.] and suturing of the mucosal grafts at the border of the hard and soft palate, seven 2-4mm fistulae were noted, however. Concluding, in spite of some shortcomings and unacceptable rate of fistula in wide clefts, the above-presented method seems to be an attractive concept. Despite some technical problems related mostly to still tested optimal filling phase, tissue expansion makes palate repair easier, probably without relaxing incisions and bone denudation. Consequently, some adverse effects on facial growth may be reduced. So far, there is no evidence for it, however, and since this is a preliminary report, there is a need for longer observations and larger material.

HdhQ111 Mice Exhibit Tissue Specific Metabolite Profiles that Include Striatal Lipid Accumulation

PubMed Central

Carroll, Jeffrey B.; Deik, Amy; Fossale, Elisa; Weston, Rory M.; Guide, Jolene R.; Arjomand, Jamshid; Kwak, Seung; Clish, Clary B.; MacDonald, Marcy E.

2015-01-01

The HTT CAG expansion mutation causes Huntington’s Disease and is associated with a wide range of cellular consequences, including altered metabolism. The mutant allele is expressed widely, in all tissues, but the striatum and cortex are especially vulnerable to its effects. To more fully understand this tissue-specificity, early in the disease process, we asked whether the metabolic impact of the mutant CAG expanded allele in heterozygous B6.HdhQ111/+ mice would be common across tissues, or whether tissues would have tissue-specific responses and whether such changes may be affected by diet. Specifically, we cross-sectionally examined steady state metabolite concentrations from a range of tissues (plasma, brown adipose tissue, cerebellum, striatum, liver, white adipose tissue), using an established liquid chromatography-mass spectrometry pipeline, from cohorts of 8 month old mutant and wild-type littermate mice that were fed one of two different high-fat diets. The differential response to diet highlighted a proportion of metabolites in all tissues, ranging from 3% (7/219) in the striatum to 12% (25/212) in white adipose tissue. By contrast, the mutant CAG-expanded allele primarily affected brain metabolites, with 14% (30/219) of metabolites significantly altered, compared to wild-type, in striatum and 11% (25/224) in the cerebellum. In general, diet and the CAG-expanded allele both elicited metabolite changes that were predominantly tissue-specific and non-overlapping, with evidence for mutation-by-diet interaction in peripheral tissues most affected by diet. Machine-learning approaches highlighted the accumulation of diverse lipid species as the most genotype-predictive metabolite changes in the striatum. Validation experiments in cell culture demonstrated that lipid accumulation was also a defining feature of mutant HdhQ111 striatal progenitor cells. Thus, metabolite-level responses to the CAG expansion mutation in vivo were tissue specific and most evident in brain, where the striatum featured signature accumulation of a set of lipids including sphingomyelin, phosphatidylcholine, cholesterol ester and triglyceride species. Importantly, in the presence of the CAG mutation, metabolite changes were unmasked in peripheral tissues by an interaction with dietary fat, implying that the design of studies to discover metabolic changes in HD mutation carriers should include metabolic perturbations. PMID:26295712

Biomechanics and mechanobiology in functional tissue engineering.

PubMed

Guilak, Farshid; Butler, David L; Goldstein, Steven A; Baaijens, Frank P T

2014-06-27

The field of tissue engineering continues to expand and mature, and several products are now in clinical use, with numerous other preclinical and clinical studies underway. However, specific challenges still remain in the repair or regeneration of tissues that serve a predominantly biomechanical function. Furthermore, it is now clear that mechanobiological interactions between cells and scaffolds can critically influence cell behavior, even in tissues and organs that do not serve an overt biomechanical role. Over the past decade, the field of "functional tissue engineering" has grown as a subfield of tissue engineering to address the challenges and questions on the role of biomechanics and mechanobiology in tissue engineering. Originally posed as a set of principles and guidelines for engineering of load-bearing tissues, functional tissue engineering has grown to encompass several related areas that have proven to have important implications for tissue repair and regeneration. These topics include measurement and modeling of the in vivo biomechanical environment; quantitative analysis of the mechanical properties of native tissues, scaffolds, and repair tissues; development of rationale criteria for the design and assessment of engineered tissues; investigation of the effects biomechanical factors on native and repair tissues, in vivo and in vitro; and development and application of computational models of tissue growth and remodeling. Here we further expand this paradigm and provide examples of the numerous advances in the field over the past decade. Consideration of these principles in the design process will hopefully improve the safety, efficacy, and overall success of engineered tissue replacements. Copyright © 2014 Elsevier Ltd. All rights reserved.

Comparison of the Effect of Dentin Bonding, Dentin Sealing Agents on the Microleakage of Provisional Crowns Fabricated with Direct and Indirect Technique-An Invitro Study

PubMed Central

Muthukumar, B; Kumar, M Vasantha

2015-01-01

Background Postoperative sensitivity after temporization is a common complaint in Fixed Partial Denture patients. It is caused by weak and ill fitting temporary restorations which results in microleakage. This can be controlled by providing good temporary restorations and by coating the exposed dentinal tubules of the prepared tooth with dentin bonding agent or dental varnish. Aim The purpose of the study was to determine the effect of dentin-bonding, dentin sealing agents on the microleakage of temporary crowns made by tooth colored auto polymerizing resin fabricated with direct and indirect technique. Materials and Methods Thirty premolar and molar human teeth were collected which were extracted recently was used for the study. The teeth were marked and divided into 3 groups each containing 10 nos. They were individually mounted with self-cure acrylic resin. It was then mounted on a milling machine and crown preparations done. Temporary crowns were fabricated by direct and indirect method with two types of materials. In group A (Control group), the temporary crowns fabricated with both direct and indirect method were cemented directly with temporary luting cement. In group B dentine-bonding agent (solobond M) was applied once to the prepared surface of each tooth specimen before the cementation of temporary crowns where as in case of group C a single layer of dental varnish is applied prior to crown cementation. The entire specimens were immersed in 1% methylene blue and allowed to undergo thermal treatment. It was then sectioned in a hard tissue microtome. Each section was evaluated for dye penetration into the dentin tubules by comparing it with a visual scale. Statistical Analysis SPSS Version 13 software was used for non-parametric data analysis by a qualified statistician. P-values less than 0.05 (p-value<0.05) were considered to be statistically significant. Results Group B (Dentin Bonding Agent) specimens cemented with crowns fabricated in direct technique showed the least amount of microleakage when compared with group A and group C. Group C (Dental Varnish) specimen showed comparatively more amount of microleakage than that of group B. Group A (control group) specimens showed the maximum amount of microleakage. Conclusion The application of a single layer of Dental varnish appears to be of no significant benefit when compared to crowns cemented with the application of Dentin bonding agent on the tooth surface. The application of a single layer of Dentin bonding agent (Solobond M) and temporary crowns fabricated with direct technique may be of some benefit for crown preparations as an interim measure prior to the luting of final crown. PMID:26266219

Isolation and culture of human multipotent stromal cells from the pancreas.

PubMed

Seeberger, Karen L; Eshpeter, Alana; Korbutt, Gregory S

2011-01-01

Mesenchymal stem cells, also termed multipotent mesenchymal stromal cells (MSCs), can be isolated from most adult tissues. Although the exact origin of MSCs expanded from the human pancreas has not been resolved, we have developed protocols to isolate and expand MSCs from human pancreatic tissue that remains after islet procurement. Similar to techniques used to isolate MSCs from bone marrow, pancreatic MSCs are isolated based on their cell adherence, expression of several cell surface antigens, and multilineage differentiation. The protocols for isolating, characterizing, and differentiating MSCs from the pancreas are presented in this chapter.

Tissue expansion and fluid absorption by skin tissue following intradermal injections through hollow microneedles

NASA Astrophysics Data System (ADS)

Shrestha, Pranav; Stoeber, Boris

2017-11-01

Hollow microneedles provide a promising alternative to conventional drug delivery techniques due to improved patient compliance and the dose sparing effect. The dynamics of fluid injected through hollow microneedles into skin, which is a heterogeneous and deformable porous medium, have not been investigated extensively in the past. We have introduced the use of Optical Coherence Tomography (OCT) for real-time visualization of fluid injections into excised porcine tissue. The results from ex-vivo experiments, including cross-sectional tissue images from OCT and pressure/flow-rate measurements, show a transient mode of high flow-rate into the tissue followed by a lower steady-state infusion rate. The injected fluid expands the underlying tissue and causes the external free surface of the skin to rise, forming a characteristic intradermal wheal. We have used OCT to visualize the evolution of tissue and free surface deformation, and advancement of the boundary between regions of expanding and stationary tissue. We will show the effect of different injection parameters such as fluid pressure, viscosity and microneedle retraction on the injected volume. This work has been supported through funding from the Collaborative Health Research Program by the Natural Science and Engineering Research Council of Canada and the Canadian Health Research Institute, and through the Canada Research Chairs program.

Does the presence of an implant including expander with internal port alter radiation dose? An ex vivo model

PubMed Central

Strang, Barbara; Murphy, Kyla; Seal, Shane; Cin, Arianna Dal

2013-01-01

BACKGROUND: There is a lack of literature examining the dosimetric implications of irradiating breast implants and expanders with internal ports inserted at the time of mastectomy. OBJECTIVE: To determine whether the presence of breast expanders with port in saline or silicone implants affect the dose uniformity across the breast when irradiated with various photon and electron energies. METHODS: One tissue-equivalent torso phantom with overlying tissue expanders in saline or silicone implants were irradiated using tangential fields with 6 MV and 18 MV photons and 9 MeV and 12 MeV electrons. All dose measurements were performed using thermoluminescent dosimeters (TLDs). The TLDs were arranged around the port and the perimeters of either the expander, or saline or silicone implant. Comparisons of measured radiation doses, and between the expected and measured doses of radiation from the TLDs on each prosthesis, were performed. Data were analyzed using two-tailed t tests. RESULTS: There were no differences in TLD measurements between the expander and the saline implant for all energy modalities, and for the expected versus actual measurements for the saline implant. Higher than anticipated measurements were recorded for a significant number of TLD positions around the silicone implants. CONCLUSIONS: Radiation doses around saline implants or expanders with internal port were unaltered, whereas dose recordings for silicone implants were higher than predicted in the present laboratory/ex vivo study. PMID:24431935

[Computed tomography in gunshot trauma. I. Ballistics elements and the mechanisms of the lesions].

PubMed

Scialpi, M; Magli, T; Boccuzzi, F; Scapati, C

1995-04-01

The knowledge of wound ballistics and of wounding mechanisms is mandatory for the radiologist to interpret the CT findings of gunshot wounds. The severity of a bullet wound depends on the characteristics of the tissue it goes through, i.e., tissue elasticity, density, thickness of the wounded body part, the type of tissue, its specific gravity, internal cohesiveness and anatomical relationships, as well as on missile characteristics, i.e., mass, shape, fragmentation and deformation. Bullet velocity is certainly a major factor in wounding, but it is only one factor. Two major wounding mechanisms exist the crushing of the bullet-struck tissue (forming the permanent cavity) and radial stretching (forming a temporary cavity). Bullet "yaw" is defined as the angle between the long axis of the bullet and its flight path. The yaw is directly proportional to tissue crushing and stretching: the wider the yaw, the most severe tissue crushing and stretching and, therefore, the more severe tissue damage. The basic knowledge of these concepts is of the utmost importance to understand the CT findings of gunshot wounds and can help physicians study and treat gunshot wounds.

Development of a biodegradable scaffold with interconnected pores by heat fusion and its application to bone tissue engineering.

PubMed

Shin, Michael; Abukawa, Harutsugi; Troulis, Maria J; Vacanti, Joseph P

2008-03-01

Tissue engineering has been proposed as an approach to alleviate the shortage of donor tissue and organs by combining cells and a biodegradable scaffold as a temporary extracellular matrix. While numerous scaffold fabrication methods have been proposed, tissue formation is typically limited to the surface of the scaffolds in bone tissue engineering applications due to early calcification on the surface. To improve tissue formation, a novel scaffold with a hierarchical interconnected pore structure on two distinct length scales has been developed. Here we present the fabrication process and the application of the scaffold to bone tissue engineering. Porous poly(lactide-co-glycolide) (PLGA) scaffolds were made by combining solvent casting/particulate leaching with heat fusion. Porcine bone marrow-derived mesenchymal stem cells (MSCs) were differentiated into osteoblasts and cultured on these scaffolds in vitro for 2, 4, and 6 weeks. Subsequently, the constructs were assessed using histology and scanning electron microscopy. The bone marrow-derived osteoblasts attached well on these scaffolds. Cells were observed throughout the scaffolds. These initial results show promise for this scaffold to aid in the regeneration of bone. (c) 2007 Wiley Periodicals, Inc.

Recovery from temporary endoplasmic reticulum stress in plants relies on the tissue-specific and largely independent roles of bZIP28 and bZIP60, as well as an antagonizing function of BAX-Inhibitor 1 upon the pro-adaptive signaling mediated by bZIP28.

PubMed

Ruberti, Cristina; Lai, YaShiuan; Brandizzi, Federica

2018-01-01

The unfolded protein response (UPR) is an ancient signaling pathway that commits to life-or-death outcomes in response to proteotoxic stress in the endoplasmic reticulum (ER). In plants, the membrane-tethered transcription factor bZIP28 and the ribonuclease-kinase IRE1 along with its splicing target, bZIP60, govern the two cytoprotective UPR signaling pathways known to date. The conserved ER membrane-associated BAX inhibitor 1 (BI1) modulates ER stress-induced programmed cell death through yet-unknown mechanisms. Despite the significance of the UPR for cell homeostasis, in plants the regulatory circuitry underlying ER stress resolution is still largely unmapped. To gain insights into the coordination of plant UPR strategies, we analyzed the functional relationship of the UPR modulators through the analysis of single and higher order mutants of IRE1, bZIP60, bZIP28 and BI1 in experimental conditions causing either temporary or chronic ER stress. We established a functional duality of bZIP28 and bZIP60, as they exert partially independent tissue-specific roles in recovery from ER stress, but redundantly actuate survival strategies in chronic ER stress. We also discovered that BI1 attenuates the pro-survival function of bZIP28 in ER stress resolution and, differently to animal cells, it does not temper the ribonuclease activity of inositol-requiring enzyme 1 (IRE1) under temporary ER stress. Together these findings reveal a functional independence of bZIP28 and bZIP60 in plant UPR, and identify an antagonizing role of BI1 in the pro-adaptive signaling mediated by bZIP28, bringing to light the distinctive complexity of the unfolded protein response (UPR) in plants. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

Decellularized adipose tissue microcarriers as a dynamic culture platform for human adipose-derived stem/stromal cell expansion.

PubMed

Yu, Claire; Kornmuller, Anna; Brown, Cody; Hoare, Todd; Flynn, Lauren E

2017-03-01

With the goal of designing a clinically-relevant expansion strategy for human adipose-derived stem/stromal cells (ASCs), methods were developed to synthesize porous microcarriers derived purely from human decellularized adipose tissue (DAT). An electrospraying approach was applied to generate spherical DAT microcarriers with an average diameter of 428 ± 41 μm, which were soft, compliant, and stable in long-term culture without chemical crosslinking. Human ASCs demonstrated enhanced proliferation on the DAT microcarriers relative to commercially-sourced Cultispher-S microcarriers within a spinner culture system over 1 month. ASC immunophenotype was maintained post expansion, with a trend for reduced expression of the cell adhesion receptors CD73, CD105, and CD29 under dynamic conditions. Upregulation of the early lineage-specific genes PPARγ, LPL, and COMP was observed in the ASCs expanded on the DAT microcarriers, but the cells retained their multilineage differentiation capacity. Comparison of adipogenic and osteogenic differentiation in 2-D cultures prepared with ASCs pre-expanded on the DAT microcarriers or Cultispher-S microcarriers revealed similar adipogenic and enhanced osteogenic marker expression in the DAT microcarrier group, which had undergone a higher population fold change. Further, histological staining results suggested a more homogeneous differentiation response in the ASCs expanded on the DAT microcarriers as compared to either Cultispher-S microcarriers or tissue culture polystyrene. A pilot chondrogenesis study revealed higher levels of chondrogenic gene and protein expression in the ASCs expanded on the DAT microcarriers relative to all other groups, including the baseline controls. Overall, this study demonstrates the promise of applying dynamic culture with tissue-specific DAT microcarriers as a means of deriving regenerative cell populations. Copyright © 2016 Elsevier Ltd. All rights reserved.

Optimizing Results of Postmastectomy Radiation Therapy Utilizing the Latissimus Dorsi Flap and Tissue Expander Technique: A Single-Center Experience

PubMed Central

Chevrollier, Guillaume S.; Greaney, Patrick J.; Jenkins, Matthew P.; Copit, Steven E.

2017-01-01

Objective: Postmastectomy radiation therapy is a well-established risk factor for complications after breast reconstruction. Even if the surgeon has a suspicion that radiation therapy may be needed, it may be beneficial to place tissue expanders during the mastectomy procedure as a temporizing measure, complete radiation therapy, and then reconstruct the breast with a latissimus flap. The purpose of this study was to examine the complication rates of the latissimus dorsi flap as compared with the complication rates of implant-based reconstruction in the setting of radiation therapy. Methods: A 16-year retrospective chart review from 2000 to 2016 was conducted. All patients who underwent temporizing tissue expander placement for radiotherapy with subsequent latissimus flap reconstruction were included in the study. Patients who did not follow up for implant exchange were excluded from the study. Results: Fifty-five patients were identified with an average age of 46.0 years (range, 27-67 years) and an average body mass index of 24.2 (range, 18.9-31.9). Five patients (9.1%) developed capsular contractures amenable to surgical intervention. One patient (1.8%) developed infection of the tissue expander, requiring removal. There were no incidences of flap failure or wound dehiscence. The average follow-up after latissimus flap reconstruction was 25.3 months (range, 3.7-121.6 months). Conclusions: We feel that the latissimus dorsi flap after postmastectomy radiation therapy represents the preferred implant-based reconstruction option to consider when the need for postmastectomy radiation therapy is anticipated. The latissimus dorsi flap remains a safe, effective solution to postmastectomy radiation therapy that every plastic surgeon should offer. PMID:29308108

Optimizing Results of Postmastectomy Radiation Therapy Utilizing the Latissimus Dorsi Flap and Tissue Expander Technique: A Single-Center Experience.

PubMed

Mohiuddin, Waseem; Chevrollier, Guillaume S; Greaney, Patrick J; Jenkins, Matthew P; Copit, Steven E

2017-01-01

Objective: Postmastectomy radiation therapy is a well-established risk factor for complications after breast reconstruction. Even if the surgeon has a suspicion that radiation therapy may be needed, it may be beneficial to place tissue expanders during the mastectomy procedure as a temporizing measure, complete radiation therapy, and then reconstruct the breast with a latissimus flap. The purpose of this study was to examine the complication rates of the latissimus dorsi flap as compared with the complication rates of implant-based reconstruction in the setting of radiation therapy. Methods: A 16-year retrospective chart review from 2000 to 2016 was conducted. All patients who underwent temporizing tissue expander placement for radiotherapy with subsequent latissimus flap reconstruction were included in the study. Patients who did not follow up for implant exchange were excluded from the study. Results: Fifty-five patients were identified with an average age of 46.0 years (range, 27-67 years) and an average body mass index of 24.2 (range, 18.9-31.9). Five patients (9.1%) developed capsular contractures amenable to surgical intervention. One patient (1.8%) developed infection of the tissue expander, requiring removal. There were no incidences of flap failure or wound dehiscence. The average follow-up after latissimus flap reconstruction was 25.3 months (range, 3.7-121.6 months). Conclusions: We feel that the latissimus dorsi flap after postmastectomy radiation therapy represents the preferred implant-based reconstruction option to consider when the need for postmastectomy radiation therapy is anticipated. The latissimus dorsi flap remains a safe, effective solution to postmastectomy radiation therapy that every plastic surgeon should offer.

Standoff Acoustic Shear Wave Imaging Using LFM Chirps

DTIC Science & Technology

2011-03-21

is typically ignored due to the large wavelengths in biological tissue. For the test material presented in this paper ( expanded polystyrene foam...inhomogeneous sound speed, 1( )c x , for a 2.5×5×7 cm steel parallelepiped embedded in a 15×23×23 cm block of expanded polystyrene foam, which

Osteogenically differentiated mesenchymal stem cells and ceramics for bone tissue engineering.

PubMed

Ohgushi, Hajime

2014-02-01

In the human body, cells having self-renewal and multi-differentiation capabilities reside in many tissues and are called adult stem cells. In bone marrow tissue, two types of stem cells are well known: hematopoietic stem cells and mesenchymal stem cells (MSCs). Though the number of MSCs in bone marrow tissue is very low, it can be increased by in vitro culture of the marrow, and culture-expanded MSCs are available for various tissue regeneration. The culture-expanded MSCs can further differentiate into osteogenic cells such as bone forming osteoblasts by culturing the MSCs in an osteogenic medium. This paper discusses osteogenically differentiated MSCs derived from the bone marrow of patients. Importantly, the differentiation can be achieved on ceramic surfaces which demonstrate mineralized bone matrix formation as well as appearance of osteogenic cells. The cell/matrix/ceramic constructs could show immediate in vivo bone formation and are available for bone reconstruction surgery. Currently, MSCs are clinically available for the regeneration of various tissues due to their high proliferation/differentiation capabilities. However, the capabilities are still limited and thus technologies to improve or recover the inherent capabilities of MSCs are needed.

A preliminary study of differentially expressed genes in expanded skin and normal skin: implications for adult skin regeneration.

PubMed

Yang, Mei; Liang, Yimin; Sheng, Lingling; Shen, Guoxiong; Liu, Kai; Gu, Bin; Meng, Fanjun; Li, Qingfeng

2011-03-01

In adults, severely damaged skin heals by scar formation and cannot regenerate to the original skin structure. However, tissue expansion is an exception, as normal skin regenerates under the mechanical stretch resulting from tissue expansion. This technique has been used clinically for defect repair and organ reconstruction for decades. However, the phenomenon of adult skin regeneration during tissue expansion has caused little attention, and the mechanism of skin regeneration during tissue expansion has not been fully understood. In this study, microarray analysis was performed on expanded human skin and normal human skin. Significant difference was observed in 77 genes, which suggest a network of several integrated cascades, including cytokines, extracellular, cytoskeletal, transmembrane molecular systems, ion or ion channels, protein kinases and transcriptional systems, is involved in the skin regeneration during expansion. Among these, the significant expression of some regeneration related genes, such as HOXA5, HOXB2 and AP1, was the first report in tissue expansion. Data in this study suggest a list of candidate genes, which may help to elucidate the fundamental mechanism of skin regeneration during tissue expansion and which may have implications for postnatal skin regeneration and therapeutic interventions in wound healing.

Multi-dimensional simulations of the expanding supernova remnant of SN 1987A

DOE Office of Scientific and Technical Information (OSTI.GOV)

Potter, T. M.; Staveley-Smith, L.; Reville, B.

The expanding remnant from SN 1987A is an excellent laboratory for investigating the physics of supernovae explosions. There is still a large number of outstanding questions, such as the reason for the asymmetric radio morphology, the structure of the pre-supernova environment, and the efficiency of particle acceleration at the supernova shock. We explore these questions using three-dimensional simulations of the expanding remnant between days 820 and 10,000 after the supernova. We combine a hydrodynamical simulation with semi-analytic treatments of diffusive shock acceleration and magnetic field amplification to derive radio emission as part of an inverse problem. Simulations show that anmore » asymmetric explosion, combined with magnetic field amplification at the expanding shock, is able to replicate the persistent one-sided radio morphology of the remnant. We use an asymmetric Truelove and McKee progenitor with an envelope mass of 10 M {sub ☉} and an energy of 1.5 × 10{sup 44} J. A termination shock in the progenitor's stellar wind at a distance of 0.''43-0.''51 provides a good fit to the turn on of radio emission around day 1200. For the H II region, a minimum distance of 0.''63 ± 0.''01 and maximum particle number density of (7.11 ± 1.78) × 10{sup 7} m{sup –3} produces a good fit to the evolving average radius and velocity of the expanding shocks from day 2000 to day 7000 after explosion. The model predicts a noticeable reduction, and possibly a temporary reversal, in the asymmetric radio morphology of the remnant after day 7000, when the forward shock left the eastern lobe of the equatorial ring.« less

Treatment of tracheomalacia with Palmaz stent: a case report.

PubMed

Inan, Mustafa; Ayvaz, Süleyman; Basaran, Umit Nusret

2005-01-01

Tracheomalacia is a potentially life-threatening clinical problem. The expandable Palmaz stent can be used for the treatment of tracheomalacia. We describe a female infant with tracheomalacia who showed respiratory distress the day after birth. Tracheomalacia was diagnosed by bronchoscopic examination, computed tomography and bronchography. At 75 days of age, an expandable metallic stent (Palmaz stent) was inserted into the trachea under fluoroscopic control. The patient's respiratory status improved rapidly. Bronchoscopic examination 6 months after the insertion did not show any granulation tissue. However, in bronchoscopic examination carried out two years later, we detected invasion of the Palmaz stent to the trachea and development of granulation tissue. We think that expandable metallic stent placement should be considered in patients who show intractable respiratory symptoms caused by tracheomalacia in the earlier stages of the treatment. But long-term complications of this procedure are crucial.

Bone as a secondary missile: an experimental study in the fragmenting of bone by high-velocity missiles.

PubMed

Amato, J J; Syracuse, D; Seaver, P R; Rich, N

1989-05-01

Destruction to soft tissues by bone fragments has been described in the literature. Civilian and military injuries have been reported in which bone fragments have acted as secondary missiles. This experimental study demonstrates, in detail, the formation of the temporary cavity within bone and the forward motion of these bone spicules. The knowledge of the ballistics will assist in the treatment of wounds caused by high-velocity missiles.

Structural variations among monocot emergent and amphibious species from lakes of the semi-arid region of Bahia, Brazil.

PubMed

Leite, K R B; França, F; Scatena, V I

2012-02-01

Temporary lakes are common in the semi-arid region of the State of Bahia and form water mirrors in the rainy season. In this period, various vegetal species appear having different life forms adapted to the seasonality conditions of the rainfall regime. This work surveyed the adaptive anatomical structures of some emergent and amphibious monocot species occurring in these lakes. We studied the anatomy of roots, rhizomes, leaves and scapes of Cyperus odoratus, Oxycaryum cubense, Pycreus macrostachyos (Cyperaceae) - amphibious species; and of Echinodorus grandiflorus (Alismataceae), Eichhornia paniculata (Pontederiaceae) and Habenaria repens (Orchidaceae) - emergent species. The anatomical features of the dermal, fundamental and vascular systems confirming the tendency of the adaptive convergence of these plants to temporary lacustrine the environment include: single layered epidermal cells with a thin cuticle layer in the aerial organs; the presence of air canals in all the organs; few or no supporting tissues; and less numerous conducting elements and thinner cell walls in the xylem. The reduction of the supporting tissues, the number of stomata, which can even be absent, and the number of conducting elements and the degree of cell wall lignification in the xylem of the emergent species is more accentuated than that of the amphibious species. The pattern of distribution of aerenchyma in the roots of the studied species was considered important to distinguish between amphibious and emergent life forms.

A temporary local energy pool coupled to neuronal activity: fluctuations of extracellular lactate levels in rat brain monitored with rapid-response enzyme-based sensor.

PubMed

Hu, Y; Wilson, G S

1997-10-01

A successfully developed enzyme-based lactate microsensor with rapid response time allows the direct and continuous in vivo measurement of lactic acid concentration with high temporal resolution in brain extracellular fluid. The fluctuations coupled to neuronal activity in extracellular lactate concentration were explored in the dentate gyrus of the hippocampus of the rat brain after electrical stimulation of the perforant pathway. Extracellular glucose and oxygen levels were also detected simultaneously by coimplantation of a fast-response glucose sensor and an oxygen electrode, to provide novel information of trafficking of energy substances in real time related to local neuronal activity. The results first give a comprehensive picture of complementary energy supply and use of lactate and glucose in the intact brain tissue. In response to acute neuronal activation, the brain tissue shifts immediately to significant energy supply by lactate. A local temporary fuel "reservoir" is established behind the blood-brain barrier, evidenced by increased extracellular lactate concentration. The pool can be depleted rapidly, up to 28% in 10-12 s, by massive, acute neuronal use after stimulation and can be replenished in approximately 20 s. Glutamate-stimulated astrocytic glycolysis and the increase of regional blood flow may regulate the lactate concentration of the pool in different time scales to maintain local energy homeostasis.

One-Step Salvage of Infected Prosthetic Breast Reconstructions Using Antibiotic-Impregnated Polymethylmethacrylate Plates and Concurrent Tissue Expander Exchange.

PubMed

Albright, Steven B; Xue, Amy S; McKnight, Aisha; Wolfswinkel, Erik M; Hollier, Larry H; Brown, Rodger H; Bullocks, Jamal M; Izaddoost, Shayan A

2016-09-01

Periprosthetic infection represents a major complication in breast reconstruction, frequently leading to expander-implant loss. Recent studies report variable success in the salvage of infected breast prostheses through systemic antibiotic therapy and surgical intervention. There is currently no consensus regarding a management algorithm for attempted salvage. The purpose of this pilot study was to evaluate the early outcomes of a protocol using antibiotic-impregnated polymethylmethacrylate (PMMA) implant placement with expander device exchange. A retrospective database was queried to identify all patients with infected implant-based breast reconstruction who were treated by the study authors and who underwent attempted salvage under the study protocol. All patients received intravenous antibiotics followed by surgical debridement of the infected pocket, insertion of antibiotic-impregnated PMMA plates and/or beads, device exchange, and postoperative antibiotics. After clinical resolution of infection, tissue expansion was performed with the PMMA implants remaining in situ until exchanged to permanent implants. All patients with infected prosthetic breast reconstructions achieved implant pocket sterilization using this method. At a mean follow-up of 8.2 months (range, 1-19 months), none of these patients have required reoperation for capsular contracture. One patient, while under treatment with prednisone for a rash, developed recurrent infection, which led to explantation of her implant. Two patients underwent radiation therapy while an antibiotic plate and tissue expander were in place, with no observed exposure or infection recurrence. Sustained local antibiotic delivery using PMMA implants and expander device exchange can successfully salvage an infected breast implant. Perceived benefits include shorter time to completed reconstruction, preserved skin envelope integrity, and possibly improved long-term aesthetic outcomes.

Tissue Expanders and Proton Beam Radiotherapy: What You Need to Know

PubMed Central

Howarth, Ashley L.; Niska, Joshua R.; Brooks, Kenneth; Anand, Aman; Bues, Martin; Vargas, Carlos E.

2017-01-01

Summary: Proton beam radiotherapy (PBR) has gained acceptance for the treatment of breast cancer because of unique beam characteristics that allow superior dose distributions with optimal dose to the target and limited collateral damage to adjacent normal tissue, especially to the heart and lungs. To determine the compatibility of breast tissue expanders (TEs) with PBR, we evaluated the structural and dosimetric properties of 2 ex vivo models: 1 model with internal struts and another model without an internal structure. Although the struts appeared to have minimal impact, we found that the metal TE port alters PBR dynamics, which may increase proton beam range uncertainty. Therefore, submuscular TE placement may be preferable to subcutaneous TE placement to reduce the interaction of the TE and proton beam. This will reduce range uncertainty and allow for more ideal radiation dose distribution. PMID:28740794

Intralesional copper wire retention and pingyangmycin injection: an effective combinational therapy for complex venous malformation in soft tissue.

PubMed

Yuan, S-M; Hong, Z-J; Jiang, H-Q; Wang, J; Hu, X-B

2014-04-01

Complex venous malformations (VMs) may extensively involve the soft tissue. The treatment remains a challenge till now. Here we introduce a combinational therapy of copper wires and pingyangmycin (bleomycin A5,PYM). Copper wires were retained in VMs by repeated penetration with a straight needle. Subsequently, PYM solution was injected into the lesion. Eight to 10 days later, copper wires were removed. The dressing was changed every day until the puncture pores healed. Magnetic resonance imaging scanning was performed to observe the change of VMs. From January 2001 to December 2011, 56 patients were treated. During the follow-up period, most of the VMs shrunk obviously. The symptoms were relieved or disappeared. The complications included local pain, temporary paraesthesia and moderate fever, which disappeared quickly after the removal of copper wires. This combinational therapy is a safe and effective approach for the complex VMs in soft tissue.

Mastectomy Skin Necrosis After Breast Reconstruction: A Comparative Analysis Between Autologous Reconstruction and Implant-Based Reconstruction.

PubMed

Sue, Gloria R; Lee, Gordon K

2018-05-01

Mastectomy skin necrosis is a significant problem after breast reconstruction. We sought to perform a comparative analysis on this complication between patients undergoing autologous breast reconstruction and patients undergoing 2-stage expander implant breast reconstruction. A retrospective review was performed on consecutive patients undergoing autologous breast reconstruction or 2-stage expander implant breast reconstruction by the senior author from 2006 through 2015. Patient demographic factors including age, body mass index, history of diabetes, history of smoking, and history of radiation to the breast were collected. Our primary outcome measure was mastectomy skin necrosis. Fisher exact test was used for statistical analysis between the 2 patient cohorts. The treatment patterns of mastectomy skin necrosis were then analyzed. We identified 204 patients who underwent autologous breast reconstruction and 293 patients who underwent 2-stage expander implant breast reconstruction. Patients undergoing autologous breast reconstruction were older, heavier, more likely to have diabetes, and more likely to have had prior radiation to the breast compared with patients undergoing implant-based reconstruction. The incidence of mastectomy skin necrosis was 30.4% of patients in the autologous group compared with only 10.6% of patients in the tissue expander group (P < 0.001). The treatment of this complication differed between these 2 patient groups. In general, those with autologous reconstructions were treated with more conservative means. Although 37.1% of patients were treated successfully with local wound care in the autologous group, only 3.2% were treated with local wound care in the tissue expander group (P < 0.001). Less than half (29.0%) of patients in the autologous group were treated with an operative intervention for this complication compared with 41.9% in the implant-based group (P = 0.25). Mastectomy skin necrosis is significantly more likely to occur after autologous breast reconstruction compared with 2-stage expander implant-based breast reconstruction. Patients with autologous reconstructions are more readily treated with local wound care compared with patients with tissue expanders, who tended to require operative treatment of this complication. Patients considering breast reconstruction should be counseled appropriately regarding the differences in incidence and management of mastectomy skin necrosis between the reconstructive options.

Bladder tissue engineering through nanotechnology.

PubMed

Harrington, Daniel A; Sharma, Arun K; Erickson, Bradley A; Cheng, Earl Y

2008-08-01

The field of tissue engineering has developed in phases: initially researchers searched for "inert" biomaterials to act solely as replacement structures in the body. Then, they explored biodegradable scaffolds--both naturally derived and synthetic--for the temporary support of growing tissues. Now, a third phase of tissue engineering has developed, through the subcategory of "regenerative medicine." This renewed focus toward control over tissue morphology and cell phenotype requires proportional advances in scaffold design. Discoveries in nanotechnology have driven both our understanding of cell-substrate interactions, and our ability to influence them. By operating at the size regime of proteins themselves, nanotechnology gives us the opportunity to directly speak the language of cells, through reliable, repeatable creation of nanoscale features. Understanding the synthesis of nanoscale materials, via "top-down" and "bottom-up" strategies, allows researchers to assess the capabilities and limits inherent in both techniques. Urology research as a whole, and bladder regeneration in particular, are well-positioned to benefit from such advances, since our present technology has yet to reach the end goal of functional bladder restoration. In this article, we discuss the current applications of nanoscale materials to bladder tissue engineering, and encourage researchers to explore these interdisciplinary technologies now, or risk playing catch-up in the future.

Visceral Blood Flow Modulation: Potential Therapy for Morbid Obesity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harris, Tyler J., E-mail: tjharris@gmail.com; Murphy, Timothy P.; Jay, Bryan S.

We present this preliminary investigation into the safety and feasibility of endovascular therapy for morbid obesity in a swine model. A flow-limiting, balloon-expandable covered stent was placed in the superior mesenteric artery of three Yorkshire swine after femoral arterial cutdown. The pigs were monitored for between 15 and 51 days after the procedure and then killed, with weights obtained at 2-week increments. In the two pigs in which the stent was flow limiting, a reduced rate of weight gain (0.42 and 0.53 kg/day) was observed relative to the third pig (0.69 kg/day), associated with temporary food aversion and signs ofmore » mesenteric ischemia in one pig.« less

THE APPLICATION OF BIOMONITORING DATA IN RISK ASSESSMENT: AN EXPANDED CASE-STUDY WITH BENZENE

EPA Science Inventory

Improved analytical methods permit the measurement of low levels of chemicals in human tissues. Despite evidence that chemicals are absorbed, it is unclear whether the relatively low levels detected in human tissue represent a potential adverse health risk. Furthermore, without...

Introduction to regenerative medicine and tissue engineering.

PubMed

Stoltz, J-F; Decot, V; Huseltein, C; He, X; Zhang, L; Magdalou, J; Li, Y P; Menu, P; Li, N; Wang, Y Y; de Isla, N; Bensoussan, D

2012-01-01

Human tissues don't regenerate spontaneously, explaining why regenerative medicine and cell therapy represent a promising alternative treatment (autologous cells or stem cells of different origins). The principle is simple: cells are collected, expanded and introduced with or without modification into injured tissues or organs. Among middle-term therapeutic applications, cartilage defects, bone repair, cardiac insufficiency, burns, liver or bladder, neurodegenerative disorders could be considered.

Expanded Transposition Flap Technique for Total and Subtotal Resurfacing of the Face and Neck

PubMed Central

Spence, Robert J.

2007-01-01

Background: The reconstruction of major burn and other deformities resulting from significant soft tissue deficits of the face and neck is a continuing challenge for surgeons who wish to reliably restore facial function and aesthetic appearance. A primary problem is deficiency of well-matched donor skin. Other problems include the unique characteristics of facial skin, the fine anatomic nuances, and the unique functional demands placed on the face. This article describes an expanded shoulder transposition flap that can provide a large amount of both flap and full-thickness skin graft for total and subtotal reconstruction of the face. Methods: An expanded shoulder transposition flap has been used since 1986 for head and neck resurfacing 58 times in 41 patients ranging in age from 2 to 62 years. The details of the technique and the results of the flap including complications are described. Results: The flap proved remarkably reliable and reproducible in resurfacing the peripheral facial aesthetic units. The pedicle skin is often used for grafting of the central face with its finer features. The donor site of the flap is closed primarily. Conclusions: Twenty years' experience with expanded transposition flaps has shown it to be reliable and versatile in the reconstruction of major soft tissue deficits of the face and neck. It is a technique that provides economy of tissue, versatility, and is well within the skill, patience, and courage of most reconstructive surgeons. PMID:17534420

Percutaneous Venous Thrombectomy Using the Arrow-Trerotola Percutaneous Thrombolytic Device (PTD) with Temporary Caval Filtration: In Vitro Investigations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wildberger, Joachim Ernst, E-mail: wildberg@rad.rwth-aachen.de; Haage, Patrick; Bovelander, Jan

2005-04-15

Purpose. To evaluate the size and quantity of downstream emboli after thrombectomy using the Arrow-Trerotola Percutaneous Thrombolytic Device (PTD) with or without temporary filtration for extensive iliofemoral and iliocaval thrombi in an in vitro flow model. Methods. Iliocaval thrombi were simulated by clotted bovine blood in a flow model (semilucent silicone tubings, diameter 12-16 mm). Five experimental set-ups were performed 10 times each; thrombus particles and distribution were measured in the effluent. First, after retrograde insertion, mechanical thrombectomy was performed using the PTD alone. Then a modified self-expanding tulip-shaped temporary vena cava stent filter was inserted additionally at the beginningmore » of each declotting procedure and removed immediately after the intervention without any manipulation within or at the filter itself. In a third step, the filter was filled with thrombus only. Here, two experiments were performed: Careful closure within the flow circuit without any additional fragmentation procedure and running the PTD within the filter lumen, respectively. In the final set-up, mechanical thrombectomy was performed within the thrombus-filled tubing as well as in the filter lumen. The latter was closed at the end of the procedure and both devices were removed from the flow circuit. Results. Running the PTD in the flow circuit without filter protection led to a fragmentation of 67.9% ({+-}7.14%) of the clot into particles {<=}500 {mu}m; restoration of flow was established in all cases. Additional placement of the filter safely allowed maceration of 82.9% ({+-}5.59%) of the thrombus. Controlled closure of the thrombus-filled filter within the flow circuit without additional mechanical treatment broke up 75.2% ({+-}10.49%), while additional mechanical thrombectomy by running the PTD within the occluded filter led to dissolution of 90.4% ({+-}3.99%) of the initial clot. In the final set-up, an overall fragmentation rate of 99.6% ({+-}0.44%) was achieved. Conclusions. The combined use of the Arrow-Trerotola PTD and a temporary vena cava stent filter proved to be effective for even large clot removal in this experimental set-up.« less

Temporary suspension of acute facial paralysis using the S-S Cable Suture (Medical U&A, Tokyo, Japan).

PubMed

Ozaki, Mine; Takushima, Akihiko; Momosawa, Akira; Kurita, Masakazu; Harii, Kiyonori

2008-07-01

For a treatment of facial paralysis, suture suspension of soft tissue is considered effective due to its less invasiveness and relatively simple technique, with minimal bruising and rapid recovery. However, suture suspension effect may not last for a long period of time. We obtained good outcome with temporary static suture suspension in 5 cases of severe facial paralysis in the intervening period between the onset of paralysis and expected spontaneous recovery. We used the S-S Cable Suture (Medical U&A, Tokyo, Japan), which was based on the modification of previously established method using the Gore-Tex cable suture originally reported by Sasaki et al in 2002. Because of the ease of technique and relatively strong lifting capability of the malar pad, we recommend it as a useful procedure for a patient suffering acute facial paralysis with possible spontaneous recovery for an improved quality of life by the quick elimination of facial distortion.

What is the future of 'organ transplantation' in the head and neck?

PubMed

Lott, David G

2014-10-01

To update readers on the current state and future of head and neck tissue transplantation. Many exciting advances have recently occurred in the field of head and neck transplantation and regenerative medicine. Larynx, face, and trachea transplants have all been successfully performed. Significant advancements in tissue engineering have occurred, including the ability to generate three-dimensional tissue structures. Transplantation of regenerated tissues has been successfully incorporated into airway reconstruction. These exciting advancements set the foundation to expand reconstructive options for dysfunctional tissues and to improve a patient's quality of life.

Development and characterization of a novel hydrogel adhesive for soft tissue applications

NASA Astrophysics Data System (ADS)

Sanders, Lindsey Kennedy

With laparoscopic and robotic surgical techniques advancing, the need for an injectable surgical adhesive is growing. To be effective, surgical adhesives for internal organs require bulk strength and compliance to avoid rips and tears, and adhesive strength to avoid leakage at the application site, while not hindering the natural healing process. Although a number of tissue adhesives and sealants approved by the FDA for surgical use are currently available, attaining a useful balance in all of these qualities has proven difficult, particularly when considering applications involving highly expandable tissue, such as bladder and lung. The long-term goal of this project is to develop a hydrogel-based tissue adhesive that provides proper mechanical properties to eliminate the need for sutures in various soft tissue applications. Tetronic (BASF), a 4-arm poly(propylene oxide)-poly(ethylene oxide) (PPO-PEO) block copolymer, has been selected as the base material for the adhesive hydrogel system. Solutions of Tetronic T1107 can support reverse thermal gelation at physiological temperatures, which can be combined with covalent crosslinking to achieve a "tandem gelation" process making it ideal for use as a tissue adhesive. The objective of this doctoral thesis research is to improve the performance of the hydrogel based tissue adhesive developed previously by Cho and co-workers by applying a multi-functionalization of Tetronic. Specifically, this research aimed to improve bonding strength of Tetronic tissue adhesive using bi-functional modification, incorporate hemostatic function to the bi-functional Tetronic hydrogel, and evaluate the safety of bi-functional Tetronic tissue adhesive both in vitro and in vivo. In summary, we have developed a fast-curing, mechanically strong hemostatic tissue adhesive that can control blood loss in wet conditions during wound treatment applications (bladder, liver and muscle). Specifically, the bi-functional Tetronic adhesive (TAS) with a proper blend ratio may be used to achieve an accurate balance in bulk and tissue bond strengths, as well as the compliance and durability for expandable organ application, such as the bladder. Incorporation of chitosan expanded the utility of the bi-functional modified T1107 (TAS) adhesive to tissue wounds on highly vascularized organs (e.g., liver, kidney). Further, we demonstrated that the modified Tetronic adhesive is biocompatible and safe for treatment of small soft tissue wounds on rat's muscle using FDA requirements. The current findings helped our understanding of the material and mechanical properties of the modified Tetronic adhesive and ultimately progress the field of surgical adhesives and sealants by providing a tunable adhesive system for various internal soft tissue wound applications.

Role of endoscopic retrograde cholangiopancreatography in the management of benign biliary strictures: What’s new?

PubMed Central

Ferreira, Rosa; Loureiro, Rui; Nunes, Nuno; Santos, António Alberto; Maio, Rui; Cravo, Marília; Duarte, Maria Antónia

2016-01-01

Benign biliary strictures comprise a heterogeneous group of diseases. The most common strictures amenable to endoscopic treatment are post-cholecystectomy, post-liver transplantation, related to primary sclerosing cholangitis and to chronic pancreatitis. Endoscopic treatment of benign biliary strictures is widely used as first line therapy, since it is effective, safe, noninvasive and repeatable. Endoscopic techniques currently used are dilation, multiple plastic stents insertion and fully covered self-expandable metal stents. The main indication for dilation alone is primary sclerosing cholangitis related strictures. In the vast majority of the remaining cases, temporary placement of multiple plastic stents with/without dilation is considered the treatment of choice. Although this approach is effective, it requires multiple endoscopic sessions due to the short duration of stent patency. Fully covered self-expandable metal stents appear as a good alternative to plastic stents, since they have an increased radial diameter, longer stent patency, easier insertion technique and similar efficacy. Recent advances in endoscopic technique and various devices have allowed successful treatment in most cases. The development of novel endoscopic techniques and devices is still ongoing. PMID:26962404

Bachmann bundle pacing reduces atrial electromechanical delay in type 1 myotonic dystrophy patients.

PubMed

Russo, Vincenzo; Rago, Anna; Papa, Andrea Antonio; Arena, Giulia; Politano, Luisa; Nigro, Gerardo

2018-04-01

Atrial electromechanical delay (AEMD) is an echocardiographic parameter correlated with the onset of supraventricular arrhythmias in several clinical conditions. Inter-atrial septal pacing in the region of Bachmann's bundle (BB) has been shown to be safe and feasible in myotonic dystrophy type 1 (DM1) patients, with a low rate of sensing and pacing defects. The aim of this study was to assess the impact of temporary BB pacing compared with right atrial appendage (RAA) pacing on AEMD in DM1 patients undergoing pacemaker (PM) implantation for cardiac rhythm abnormalities. The study enrolled 70 consecutive DM1 patients undergoing PM implantation for cardiac rhythm abnormalities in accordance with the current guidelines. Seventy age- and sex-matched non-DM1 patients undergoing dual-chamber PM implantation for cardiac rhythm abnormalities were used as controls. The atrial pacing lead was temporarily positioned in the RAA and on the right side of the inter-atrial septum in the region of Bachmann's bundle. For each site (BB and RAA), temporary atrial pacing in the AAI mode was established at 10 beats per minute above the sinus rate and a detailed trans-thoracic echocardiogram with tissue Doppler (TDI) analysis was recorded after at least 10 min of atrial pacing to evaluate AEMD. Temporary RAA pacing did not show statistically significant differences in inter-AEMD (48.2 ± 17.8 vs 50.5 ± 16.5 ms; P = 0.8), intra-left AEMD (43.3 ± 15.5 vs 44.6 ± 15.8 ms; P = 0.1), or intra-right-AEMD (14.1 ± 4.2 vs 15.4 ± 5.8 ms; P = 0.9), in comparison with sinus rhythm. Temporary BB pacing determined a significantly lower inter-AEMD (36.1 ± 17.1 vs 50.5 ± 16.5 ms; P = 0.001) and intra-left AEMD (32.5 ± 15.2 vs 44.6 ± 15.8 ms; P = 0.001) values in comparison with temporary RAA pacing. No statistically significant difference was found in intra-right AEMD (12.2 ± 4.6 vs 15.4 ± 5.8 ms; P = 0.2). In the control group, neither temporary RAA pacing nor temporary BB pacing showed statistically significant differences in inter-AEMD, intra-left AEMD, or intra-right AEMD values in comparison with sinus rhythm. In DM1 patients undergoing dual-chamber PM implantation, atrial pacing in the Bachmann bundle region is associated with significantly lower echocardiographic indices of atrial electromechanical delay (inter-AEMD and intra-left AEMD) in comparison with RAA pacing.

Effects of tissue stiffness, ultrasound frequency, and pressure on histotripsy-induced cavitation bubble behavior.

PubMed

Vlaisavljevich, Eli; Lin, Kuang-Wei; Warnez, Matthew T; Singh, Rahul; Mancia, Lauren; Putnam, Andrew J; Johnsen, Eric; Cain, Charles; Xu, Zhen

2015-03-21

Histotripsy is an ultrasound ablation method that controls cavitation to fractionate soft tissue. In order to effectively fractionate tissue, histotripsy requires cavitation bubbles to rapidly expand from nanometer-sized initial nuclei into bubbles often larger than 50 µm. Using a negative pressure high enough to initiate a bubble cloud and expand bubbles to a sufficient size, histotripsy has been shown capable of completely fractionating soft tissue into acelluar debris resulting in effective tissue removal. Previous work has shown that the histotripsy process is affected by tissue mechanical properties with stiffer tissues showing increased resistance to histotripsy fractionation, which we hypothesize to be caused by impeded bubble expansion in stiffer tissues. In this study, the hypothesis that increases in tissue stiffness cause a reduction in bubble expansion was investigated both theoretically and experimentally. High speed optical imaging was used to capture a series of time delayed images of bubbles produced inside mechanically tunable agarose tissue phantoms using histotripsy pulses produced by 345 kHz, 500 kHz, 1.5 MHz, and 3 MHz histotripsy transducers. The results demonstrated a significant decrease in maximum bubble radius (Rmax) and collapse time (tc) with both increasing Young's modulus and increasing frequency. Furthermore, results showed that Rmax was not increased by raising the pressure above the intrinsic threshold. Finally, this work demonstrated the potential of using a dual-frequency strategy to modulate the expansion of histotripsy bubbles. Overall, the results of this study improve our understanding of how tissue stiffness and ultrasound parameters affect histotripsy-induced bubble behavior and provide a rational basis to tailor acoustic parameters for treatment of the specific tissues of interest.

Effects of tissue stiffness, ultrasound frequency, and pressure on histotripsy-induced cavitation bubble behavior

NASA Astrophysics Data System (ADS)

Vlaisavljevich, Eli; Lin, Kuang-Wei; Warnez, Matthew T.; Singh, Rahul; Mancia, Lauren; Putnam, Andrew J.; Johnsen, Eric; Cain, Charles; Xu, Zhen

2015-03-01

Histotripsy is an ultrasound ablation method that controls cavitation to fractionate soft tissue. In order to effectively fractionate tissue, histotripsy requires cavitation bubbles to rapidly expand from nanometer-sized initial nuclei into bubbles often larger than 50 µm. Using a negative pressure high enough to initiate a bubble cloud and expand bubbles to a sufficient size, histotripsy has been shown capable of completely fractionating soft tissue into acelluar debris resulting in effective tissue removal. Previous work has shown that the histotripsy process is affected by tissue mechanical properties with stiffer tissues showing increased resistance to histotripsy fractionation, which we hypothesize to be caused by impeded bubble expansion in stiffer tissues. In this study, the hypothesis that increases in tissue stiffness cause a reduction in bubble expansion was investigated both theoretically and experimentally. High speed optical imaging was used to capture a series of time delayed images of bubbles produced inside mechanically tunable agarose tissue phantoms using histotripsy pulses produced by 345 kHz, 500 kHz, 1.5 MHz, and 3 MHz histotripsy transducers. The results demonstrated a significant decrease in maximum bubble radius (Rmax) and collapse time (tc) with both increasing Young’s modulus and increasing frequency. Furthermore, results showed that Rmax was not increased by raising the pressure above the intrinsic threshold. Finally, this work demonstrated the potential of using a dual-frequency strategy to modulate the expansion of histotripsy bubbles. Overall, the results of this study improve our understanding of how tissue stiffness and ultrasound parameters affect histotripsy-induced bubble behavior and provide a rational basis to tailor acoustic parameters for treatment of the specific tissues of interest.

Reconstruction of large unilateral hemi-facial scar contractures with supercharged expanded forehead flaps based on the anterofrontal superficial temporal vessels.

PubMed

Gan, Cheng; Fan, Jincai; Liu, Liqiang; Tian, Jia; Jiao, Hu; Chen, Wenlin; Fu, Siqi; Feng, Suyun

2013-11-01

The expanded forehead flap, using temporal pedicles, has been employed extensively in facial reconstruction. To overcome the disadvantages of the traditional dual temporal pedicles, such as the limited transfer range and the short length of the flap, the distal supercharging technique can be applied to lengthen the flap and extend the transfer range, especially in the cases with a past temporal burn injury. This article aims to present an application of the distal supercharged expanded forehead flap procedure for hemi-facial reconstruction and discuss the haemodynamics of the expanded forehead flap. The tissue expander implantation and the following forehead tissue expansion were performed regularly. When the forehead skin expansion was completed, an expanded forehead flap was created and transferred to the damaged facial area with one distal temporal vessel pedicle that was anastomosed with facial vessels in a supercharged way. All patients were analysed retrospectively. From September 2009 to September 2011, eight male patients and one female patient were treated using this method. Their flaps size ranged from 20 cm × 8 cm to 30 cm × 11 cm and no flap loss occurred. Patients came in for follow-ups 9-16 months after the procedures. All the patients were satisfied with the results. The supercharging expanded forehead flap procedure can provide reliable flap vascularity due to its elastic transferring abilities. By using a distal supercharging technique, we can lengthen and widen the flap to tailor it to the defect, while also minimising the donor defect in the patients with a past temporal injury. Copyright © 2013 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Scaffold-assisted cartilage tissue engineering using infant chondrocytes from human hip cartilage.

PubMed

Kreuz, P C; Gentili, C; Samans, B; Martinelli, D; Krüger, J P; Mittelmeier, W; Endres, M; Cancedda, R; Kaps, C

2013-12-01

Studies about cartilage repair in the hip and infant chondrocytes are rare. The aim of our study was to evaluate the use of infant articular hip chondrocytes for tissue engineering of scaffold-assisted cartilage grafts. Hip cartilage was obtained from five human donors (age 1-10 years). Expanded chondrocytes were cultured in polyglycolic acid (PGA)-fibrin scaffolds. De- and re-differentiation of chondrocytes were assessed by histological staining and gene expression analysis of typical chondrocytic marker genes. In vivo, cartilage matrix formation was assessed by histology after subcutaneous transplantation of chondrocyte-seeded PGA-fibrin scaffolds in immunocompromised mice. The donor tissue was heterogenous showing differentiated articular cartilage and non-differentiated tissue and considerable expression of type I and II collagens. Gene expression analysis showed repression of typical chondrocyte and/or mesenchymal marker genes during cell expansion, while markers were re-induced when expanded cells were cultured in PGA-fibrin scaffolds. Cartilage formation after subcutaneous transplantation of chondrocyte loaded PGA-fibrin scaffolds in nude mice was variable, with grafts showing resorption and host cell infiltration or formation of hyaline cartilage rich in type II collagen. Addition of human platelet rich plasma (PRP) to cartilage grafts resulted robustly in formation of hyaline-like cartilage that showed type II collagen and regions with type X collagen. These results suggest that culture of expanded and/or de-differentiated infant hip cartilage cells in PGA-fibrin scaffolds initiates chondrocyte re-differentiation. The heterogenous donor tissue containing immature chondrocytes bears the risk of cartilage repair failure in vivo, which may be possibly overcome by the addition of PRP. Copyright © 2013 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Stem Cell Therapy with Overexpressed VEGF and PDGF Genes Improves Cardiac Function in a Rat Infarct Model

PubMed Central

Das, Hiranmoy; George, Jon C.; Joseph, Matthew; Das, Manjusri; Abdulhameed, Nasreen; Blitz, Anna; Khan, Mahmood; Sakthivel, Ramasamy; Mao, Hai-Quan; Hoit, Brian D.; Kuppusamy, Periannan; Pompili, Vincent J.

2009-01-01

Background Therapeutic potential was evaluated in a rat model of myocardial infarction using nanofiber-expanded human cord blood derived hematopoietic stem cells (CD133+/CD34+) genetically modified with VEGF plus PDGF genes (VIP). Methods and Findings Myocardial function was monitored every two weeks up to six weeks after therapy. Echocardiography revealed time dependent improvement of left ventricular function evaluated by M-mode, fractional shortening, anterior wall tissue velocity, wall motion score index, strain and strain rate in animals treated with VEGF plus PDGF overexpressed stem cells (VIP) compared to nanofiber expanded cells (Exp), freshly isolated cells (FCB) or media control (Media). Improvement observed was as follows: VIP>Exp> FCB>media. Similar trend was noticed in the exercise capacity of rats on a treadmill. These findings correlated with significantly increased neovascularization in ischemic tissue and markedly reduced infarct area in animals in the VIP group. Stem cells in addition to their usual homing sites such as lung, spleen, bone marrow and liver, also migrated to sites of myocardial ischemia. The improvement of cardiac function correlated with expression of heart tissue connexin 43, a gap junctional protein, and heart tissue angiogenesis related protein molecules like VEGF, pNOS3, NOS2 and GSK3. There was no evidence of upregulation in the molecules of oncogenic potential in genetically modified or other stem cell therapy groups. Conclusion Regenerative therapy using nanofiber-expanded hematopoietic stem cells with overexpression of VEGF and PDGF has a favorable impact on the improvement of rat myocardial function accompanied by upregulation of tissue connexin 43 and pro-angiogenic molecules after infarction. PMID:19809493

Fabrication of three-dimensional scaffolds using precision extrusion deposition with an assisted cooling device.

PubMed

Hamid, Q; Snyder, J; Wang, C; Timmer, M; Hammer, J; Guceri, S; Sun, W

2011-09-01

In the field of biofabrication, tissue engineering and regenerative medicine, there are many methodologies to fabricate a building block (scaffold) which is unique to the target tissue or organ that facilitates cell growth, attachment, proliferation and/or differentiation. Currently, there are many techniques that fabricate three-dimensional scaffolds; however, there are advantages, limitations and specific tissue focuses of each fabrication technique. The focus of this initiative is to utilize an existing technique and expand the library of biomaterials which can be utilized to fabricate three-dimensional scaffolds rather than focusing on a new fabrication technique. An expanded library of biomaterials will enable the precision extrusion deposition (PED) device to construct three-dimensional scaffolds with enhanced biological, chemical and mechanical cues that will benefit tissue generation. Computer-aided motion and extrusion drive the PED to precisely fabricate micro-scaled scaffolds with biologically inspired, porosity, interconnectivity and internal and external architectures. The high printing resolution, precision and controllability of the PED allow for closer mimicry of tissues and organs. The PED expands its library of biopolymers by introducing an assisting cooling (AC) device which increases the working extrusion temperature from 120 to 250 °C. This paper investigates the PED with the integrated AC's capabilities to fabricate three-dimensional scaffolds that support cell growth, attachment and proliferation. Studies carried out in this paper utilized a biopolymer whose melting point is established to be 200 °C. This polymer was selected to illustrate the newly developed device's ability to fabricate three-dimensional scaffolds from a new library of biopolymers. Three-dimensional scaffolds fabricated with the integrated AC device should illustrate structural integrity and ability to support cell attachment and proliferation.

Neural Stem Cells Derived Directly from Adipose Tissue.

PubMed

Petersen, Eric D; Zenchak, Jessica R; Lossia, Olivia V; Hochgeschwender, Ute

2018-05-01

Neural stem cells (NSCs) are characterized as self-renewing cell populations with the ability to differentiate into the multiple tissue types of the central nervous system. These cells can differentiate into mature neurons, astrocytes, and oligodendrocytes. This category of stem cells has been shown to be a promisingly effective treatment for neurodegenerative diseases and neuronal injury. Most treatment studies with NSCs in animal models use embryonic brain-derived NSCs. This approach presents both ethical and feasibility issues for translation to human patients. Adult tissue is a more practical source of stem cells for transplantation therapies in humans. Some adult tissues such as adipose tissue and bone marrow contain a wide variety of stem cell populations, some of which have been shown to be similar to embryonic stem cells, possessing many pluripotent properties. Of these stem cell populations, some are able to respond to neuronal growth factors and can be expanded in vitro, forming neurospheres analogous to cells harvested from embryonic brain tissue. In this study, we describe a method for the collection and culture of cells from adipose tissue that directly, without going through intermediates such as mesenchymal stem cells, results in a population of NSCs that are able to be expanded in vitro and be differentiated into functional neuronal cells. These adipose-derived NSCs display a similar phenotype to those directly derived from embryonic brain. When differentiated into neurons, cells derived from adipose tissue have spontaneous spiking activity with network characteristics similar to that of neuronal cultures.

The role of adipokines in chronic inflammation

PubMed Central

Mancuso, Peter

2016-01-01

Adipose tissue has traditionally been defined as connective tissue that stores excess calories in the form of triacylglycerol. However, the physiologic functions attributed to adipose tissue are expanding, and it is now well established that adipose tissue is an endocrine gland. Among the endocrine factors elaborated by adipose tissue are the adipokines; hormones, similar in structure to cytokines, produced by adipose tissue in response to changes in adipocyte triacylglycerol storage and local and systemic inflammation. They inform the host regarding long-term energy storage and have a profound influence on reproductive function, blood pressure regulation, energy homeostasis, the immune response, and many other physiologic processes. The adipokines possess pro- and anti-inflammatory properties and play a critical role in integrating systemic metabolism with immune function. In calorie restriction and starvation, proinflammatory adipokines decline and anti-inflammatory adipokines increase, which informs the host of energy deficits and contributes to the suppression of immune function. In individuals with normal metabolic status, there is a balance of pro- and anti-inflammatory adipokines. This balance shifts to favor proinflammatory mediators as adipose tissue expands during the development of obesity. As a consequence, the proinflammatory status of adipose tissue contributes to a chronic low-grade state of inflammation and metabolic disorders associated with obesity. These disturbances are associated with an increased risk of metabolic disease, type 2 diabetes, cardiovascular disease, and many other pathological conditions. This review focuses on the impact of energy homeostasis on the adipokines in immune function. PMID:27529061

Comparative analysis of poly-glycolic acid-based hybrid polymer starter matrices for in vitro tissue engineering.

PubMed

Generali, Melanie; Kehl, Debora; Capulli, Andrew K; Parker, Kevin K; Hoerstrup, Simon P; Weber, Benedikt

2017-10-01

Biodegradable scaffold matrixes form the basis of any in vitro tissue engineering approach by acting as a temporary matrix for cell proliferation and extracellular matrix deposition until the scaffold is replaced by neo-tissue. In this context several synthetic polymers have been investigated, however a concise systematic comparative analyses is missing. Therefore, the present study systematically compares three frequently used polymers for the in vitro engineering of extracellular matrix based on poly-glycolic acid (PGA) under static as well as dynamic conditions. Ultra-structural analysis was used to examine the polymers structure. For tissue engineering (TE) three human fibroblast cell lines were seeded on either PGA-poly-4-hydroxybutyrate (P4HB), PGA-poly-lactic acid (PLA) or PGA-poly-caprolactone (PCL) patches. These patches were analyzed after 21days of culture qualitative by histology and quantitative by determining the amount of DNA, glycosaminoglycan and hydroxyproline. We found that PGA-P4HB and PGA-PLA scaffolds enhance tissue formation significantly higher than PGA-PCL scaffolds (p<0.05). Polymer remnants were visualized by polarization microscopy. In addition, biomechanical properties of the tissue engineered patches were determined in comparison to native tissue. This study may allow future studies to specifically select certain polymer starter matrices aiming at specific tissue properties of the bioengineered constructs in vitro. Copyright © 2017 Elsevier B.V. All rights reserved.

[Study of changes in the enzyme-salt composition affecting the permeability of ocular tissues under infrasound phonophoresis].

PubMed

Filatov, V V

2005-01-01

This paper deals with the study of infrasound phonophoresis-induced changes in biochemical factors, which affect the permeability of eyeball tissues. During 10 days, the rabbit right eye was exposed to an infrasound in the changing pressure mode at 4 Hz and 173 dB for 10 minutes every day. The left eye remained control. After finishing a series of studies, the animals were slaughtered, the eyes were enucleated and prepared into individual tissues. Changes in sodium-potassium composition were investigated in the first series. By causing a reduction in the cellular content of K+, infrasound exposure was found to cause a decrease in membranous potential and activation Na-channel, as confirmed by the elevated intracellular levels of Na+. This in turn enhances ocular tissue permeability for drugs without damaging the structure of a cell membrane. Changes in the activity of the following enzymes: beta-glucosidase, cathepsin D, and hy- aluronidase. Infrasound was ascertained to enhance the activity of beta-glucosidase, which accounts for the lower levels of glucose in ocular tissues and points to the activation and acceleration of biochemical processes in the tissues. At the same time the increased concentrations of cathepsin D and hyaluronidase found in ocular tissues were responsible for a temporary reduction in the viscosity of hyaluronic acid, which promotes resolution of opacities, adhesions or scars and increased tissue permeability.

Expansion method in secondary total ear reconstruction for undesirable reconstructed ear.

PubMed

Liu, Tun; Hu, Jintian; Zhou, Xu; Zhang, Qingguo

2014-09-01

Ear reconstruction by autologous costal cartilage grafting is the most widely applied technique with fewer complications. However, undesirable ear reconstruction brings more problems to plastic surgeons. Some authors resort to free flap or osseointegration technique with prosthetic ear. In this article, we introduce a secondary total ear reconstruction with expanded skin flap method. From July 2010 to April 2012, 7 cases of undesirable ear reconstruction were repaired by tissue expansion method. Procedures including removal of previous cartilage framework, soft tissue expander insertion, and second stage of cartilage framework insertion were performed to each case regarding their local conditions. The follow-up time ranged from 6 months to 2.5 years. All of the cases recovered well with good 3-dimensional forms, symmetrical auriculocephalic angle, and stable fixation. All these evidence showed that this novel expansion method is safe, stable, and less traumatic for secondary total ear reconstruction. With sufficient expanded skin flap and refabricated cartilage framework, lifelike appearance of reconstructed ear could be acquired without causing additional injury.

Nummular Eczema of Breast: A Potential Dermatologic Complication after Mastectomy and Subsequent Breast Reconstruction

PubMed Central

Iwahira, Yoshiko; Nagasao, Tomohisa; Shimizu, Yusuke; Kuwata, Kumiko; Tanaka, Yoshio

2015-01-01

Purposes. The present paper reports clinical cases where nummular eczema developed during the course of breast reconstruction by means of implantation and evaluates the occurrence patterns and ratios of this complication. Methods. 1662 patients undergoing breast reconstruction were reviewed. Patients who developed nummular eczema during the treatment were selected, and a survey was conducted on these patients regarding three items: (1) the stage of the treatment at which nummular eczema developed; (2) time required for the lesion to heal; (3) location of the lesion on the reconstructed breast(s). Furthermore, histopathological examination was conducted to elucidate the etiology of the lesion. Results. 48 patients (2.89%) developed nummular eczema. The timing of onset varied among these patients, with lesions developing after the placement of tissue expanders for 22 patients (45.8%); after the tissue expanders were replaced with silicone implants for 12 patients (25%); and after nipple-areola complex reconstruction for 14 patients (29.2%). Nummular eczema developed both in periwound regions (20 cases: 41.7%) and in nonperiwound regions (32 cases: 66.7%). Histopathological examination showed epidermal acanthosis, psoriasiform patterns, and reduction of sebaceous glands. Conclusions. Surgeons should recognize that nummular eczema is a potential complication of breast reconstruction with tissue expanders and silicone implants. PMID:26380109

Mesenchymal Stem Cell Transplantation in Multiple Sclerosis

PubMed Central

Cohen, Jeffrey A.

2013-01-01

Mesenchymal stem cells (MSCs) are a pluripotent non-hematopoietic precursor cells that can be isolated from bone marrow and numerous other tissues, culture-expanded to purity, and induced to differentiate in vitro and in vivo into mesodermal derivatives. MSCs exhibit many phenotypic and functional similarities to pericytes. The immunomodulatory, tissue protective, and repair-promoting properties of MSCs demonstrated both in vitro and in animal models make them an attractive potential therapy for MS and other conditions characterized by inflammation and/or tissue injury. Other potential advantages of MSCs as a therapeutic include the relative ease of culture expansion, relative immunoprivilege allowing allogeneic transplantation, and their ability to traffic from blood to areas of tissue allowing intravascular administration. The overall published experience with MSC transplantation in MS is modest, but several small case series and preliminary studies yielded promising results. Several groups, including us, recently initiated formal studies of autologous, culture-expanded, bone-marrow-derived MSC transplantation in MS. Although there are several potential safety concerns, to date, the procedure has been well tolerated. Future studies that more definitively assess efficacy also will need to address several technical issues. PMID:23294498

Tissue expansion in the treatment of giant congenital melanocytic nevi of the upper extremity

PubMed Central

Ma, Tengxiao; Fan, Ke; Li, Lei; Xie, Feng; Li, Hao; Chou, Haiyan; Zhang, Zhengwen

2017-01-01

Abstract The aim of our study was to use tissue expansion for the treatment of giant congenital melanocytic nevi of the upper extremity and examine potential advantages over traditional techniques. There were 3 stages in the treatment of giant congenital melanocytic nevi of the upper extremities using tissue expansion: first, the expander was inserted into the subcutaneous pocket; second, the expander was removed, lesions were excised, and the wound of the upper extremity was placed into the pocket to delay healing; third, the residual lesion was excised and the pedicle was removed. The pedicle flap was then unfolded to resurface the wound. During the period between June 2007 and December 2015, there were 11 patients with giant congenital melanocytic nevi of the upper extremities who underwent reconstruction at our department with skin expansion. Few complications were noted in each stage of treatment. The functional and aesthetic results were observed and discussed in this study. Optimal aesthetic and functional results were obtained using tissue expansion to reconstruct the upper extremities due to the giant congenital melanocytic nevi. PMID:28353563

Endoluminal ultrasound applicator configurations utilizing deployable arrays, reflectors and lenses to augment and dynamically adjust treatment volume, gain, and depth

NASA Astrophysics Data System (ADS)

Adams, Matthew S.; Salgaonkar, Vasant A.; Sommer, Graham; Diederich, Chris J.

2017-02-01

Endoluminal high-intensity ultrasound offers spatially-precise thermal ablation of tissues adjacent to body lumens, but is constrained in treatment volume and penetration depth by the effective aperture of integrated transducers, which are limited in size to enable delivery through anatomical passages, endoscopic instrumentation, or laparoscopic ports. This study introduced and investigated three distinct endoluminal ultrasound applicator designs that can be delivered in a compact state then deployed or expanded at the target luminal site to increase the effective therapeutic aperture. The first design incorporated an array of planar transducers which could be unfolded at specific angles of convergence between the transducers. Two alternative designs consisted of fixed transducer sources surrounded by an expandable multicompartment balloon that contained acoustic reflector and dynamically-adjustable fluid lenses compartments. Parametric studies of acoustic output were performed across device design parameters via the rectangular radiator and secondary sources methods. Biothermal models were used to simulate resulting temperature distributions in three-dimensional heterogeneous tissue models. Simulations indicate that a deployable transducer array can increase volumetric coverage and penetration depth by 80% and 20%, respectively, while permitting more conformal thermal lesion shapes based on the degree of convergence between the transducers. The applicator designs incorporating reflector and fluid lenses demonstrated enhanced focal gain and penetration depth that increased with the diameter of the expanded reflector-lens balloon. Thermal simulations of assemblies with 12 mm compact profiles and 50 mm expanded balloon diameters demonstrated generation of localized thermal lesions at depths up to 10 cm in liver tissue.

Metabolic Biofouling of Glucose Sensors in Vivo: Role of Tissue Microhemorrhages

PubMed Central

Klueh, Ulrike; Liu, Zenghe; Feldman, Ben; Henning, Timothy P; Cho, Brian; Ouyang, Tianmei; Kreutzer, Don

2011-01-01

Objective: Based on our in vitro study that demonstrated the adverse effects of blood clots on glucose sensor function, we hypothesized that in vivo local tissue hemorrhages, induced as a consequence of sensor implantation or sensor movement post-implantation, are responsible for unreliable readings or an unexplained loss of functionality shortly after implantation. Research Design and Methods: To investigate this issue, we utilized real-time continuous monitoring of blood glucose levels in a mouse model. Direct injection of blood at the tissue site of sensor implantation was utilized to mimic sensor-induced local tissue hemorrhages. Results: It was found that blood injections, proximal to the sensor, consistently caused lowered sensor glucose readings, designated temporary signal reduction, in vivo in our mouse model, while injections of plasma or saline did not have this effect. Conclusion: These results support our hypothesis that tissue hemorrhage and resulting blood clots near the sensor can result in lowered local blood glucose concentrations due to metabolism of glucose by the clot. The lowered local blood glucose concentration led to low glucose readings from the still functioning sensor that did not reflect the systemic glucose level. PMID:21722574

The Dermal Apron Technique for Immediate Implant Socket Management: A Novel Technique.

PubMed

Levin, Barry P

2016-01-01

With immediate implant placement and provisionalization (IIP) in the esthetic zone, measures to counter hard and soft tissue loss are frequently necessary. To reduce the morbidity associated with bone and connective tissue procurement, various exogenous materials are utilized. The "Dermal Apron Technique" presented in this article demonstrates the use of a composite bone particulate (allograft/xenograft) plus a dermal allograft, adapted around screw-retained temporary crowns and secured within a subperiosteal pouch. The purpose is to augment the thickness of peri-implant mucosa for the purpose of preserving ridge dimensions and preventing mucosal recession. Controlled studies are required to further support its use. Clinical significance: Soft tissue health and harmony are critical for successful implant therapy in the esthetic regions of the dentition. Often, autogenous soft tissue grafts are used to augment peri-implant soft tissues. The Dermal Apron Technique is a method, that in specific situations, obviates the need for autogenous grafting. This reduces treatment time and morbidity associated with procurement of these grafts. The Dermal Apron Technique is used simultaneous with immediate placement and provisionalization and can improve long-term esthetic outcomes for patients. © 2016 Wiley Periodicals, Inc.

[Reconstructive surgery of penile deformities and tissue deficiencies].

PubMed

Kelemen, Zsolt

2009-05-31

Penile deformities and tissue deficiencies can disturb sexual intercourse or make it impossible. The aim of the study is to summarize the different diseases according to their clinical appearance and pathological processes and to review operative methods and personal experiences. Surgical treatment of hypo- and epispadias is usually performed in childhood, but curvatures after unsuccessful operation can demand the reconstruction of urethra, skin and corpora cavernosa eventually. Peyronie's disease and curvature after penile fracture desire the reconstruction of tunica albuginea. Plaque surgery used to be performed with dermal, tunica vaginalis or venous grafts, but best results are obtained by shortening procedure on the contralateral side according to the Heinecke-Mikulitz principle. Tissue deficiencies and curvatures were observed after necrotic inflammatory processes, like Fournier's gangrene or chronic dermatitis. Skin defects were cured by flaps and grafts. Abscesses of penis, severe tissue defects and also curvatures were observed after intracavernous injection in cases of erectile dysfunction. Possibilities of reconstruction seem to be very poor. Oil granuloma of penis presents a new task for penile reconstruction. The best results of skin replacement were achieved by temporary embedding of the penis in scrotum.

Use of silicone tracheal stoma stents for temporary tracheostomy in dogs with upper airway obstruction.

PubMed

Trinterud, T; Nelissen, P; White, R A S

2014-11-01

To report the use of silicone tracheal stoma stents for temporary tracheostomy in dogs with upper airway obstruction. Retrospective review of medical records for dogs in which silicone tracheal stoma stents were placed. Eighteen dogs had a silicone tracheal stoma stent placed for maintenance of a tracheostomy stoma for periods ranging from three hours to eight months. No intra-operative or immediate postoperative complications were recorded. In 11 dogs the stent was removed by simple traction after a period ranging from 36 hours to 6 weeks, and the tracheal stoma was left to heal by second intention. Five of the 18 dogs were determined as being tracheostomy dependent and underwent conversion to permanent tracheostomy after a period ranging from five days to eight months following stent placement. One dog was euthanased after three months, with the stent still in place, because of poor respiratory function, and one dog died of unrelated reasons. In 6 of 10 dogs (60%) where the stent was in place for five days or more, granulation tissue formation caused dislodgement of the stent. Silicone tracheal stoma stents may be used as an alternative to conventional tracheostomy tubes in selected dogs with upper airway obstruction. Long-term use of the stent beyond five days is not recommended because of granulation tissue formation. The long-term consequences of partial tracheal ring resection are unknown. © 2014 British Small Animal Veterinary Association.

Applications of Tissue Engineering in Joint Arthroplasty: Current Concepts Update.

PubMed

Zeineddine, Hussein A; Frush, Todd J; Saleh, Zeina M; El-Othmani, Mouhanad M; Saleh, Khaled J

2017-07-01

Research in tissue engineering has undoubtedly achieved significant milestones in recent years. Although it is being applied in several disciplines, tissue engineering's application is particularly advanced in orthopedic surgery and in degenerative joint diseases. The literature is full of remarkable findings and trials using tissue engineering in articular cartilage disease. With the vast and expanding knowledge, and with the variety of techniques available at hand, the authors aimed to review the current concepts and advances in the use of cell sources in articular cartilage tissue engineering. Copyright © 2017 Elsevier Inc. All rights reserved.

Establishment of mouse expanded potential stem cells

PubMed Central

Gao, Xuefei; Antunes, Liliana; Yu, Yong; Zhu, Zhexin; Wang, Juexuan; Kolodziejczyk, Aleksandra A.; Campos, Lia S.; Wang, Cui; Yang, Fengtang; Zhong, Zhen; Fu, Beiyuan; Eckersley-Maslin, Melanie A.; Woods, Michael; Tanaka, Yosuke; Chen, Xi; Wilkinson, Adam C.; Bussell, James; White, Jacqui; Ramirez-Solis, Ramiro; Reik, Wolf; Göttgens, Berthold; Teichmann, Sarah A.; Tam, Patrick P. L.; Nakauchi, Hiromitsu; Zou, Xiangang; Lu, Liming; Liu, Pentao

2018-01-01

Mouse embryonic stem cells derived from the epiblast1 contribute to the somatic lineages and the germline but are excluded from the extra-embryonic tissues that are derived from the trophectoderm and the primitive endoderm2 upon reintroduction to the blastocyst. Here we report that cultures of expanded potential stem cells can be established from individual eight-cell blastomeres, and by direct conversion of mouse embryonic stem cells and induced pluripotent stem cells. Remarkably, a single expanded potential stem cell can contribute both to the embryo proper and to the trophectoderm lineages in a chimaera assay. Bona fide trophoblast stem cell lines and extra-embryonic endoderm stem cells can be directly derived from expanded potential stem cells in vitro. Molecular analyses of the epigenome and single-cell transcriptome reveal enrichment for blastomere-specific signature and a dynamic DNA methylome in expanded potential stem cells. The generation of mouse expanded potential stem cells highlights the feasibility of establishing expanded potential stem cells for other mammalian species. PMID:29019987

Adjustable perineal male sling using tissue expander as an effective treatment of post-prostatectomy urinary incontinence.

PubMed

Balci, Melih; Tuncel, Altug; Bilgin, Ovunc; Aslan, Yilmaz; Atan, Ali

2015-01-01

To report our intermediate experience in treating patients with severe incontinence using an adjustable perineal male sling with a tissue expander. An adjustable male sling procedure was performed on 21 patients with severe incontinence. The underlying etiology of urinary incontinence was radical prostatectomy in 13 patients, open prostatectomy in 5 patients and transurethral prostate resection in 3 patients. The difference between the classical and the adjustable sling is that in the latter there is a 25 mL tissue expander between the two layers of polypropylene mesh with an injection port. Adjustment of the sling was performed with saline via an inflation port, in case of recurrence or persistence of incontinence. The mean age of the patients was 66.2 ± 7.3 (50-79) years and mean pad usage was 6.4 ± 0.6 per day. The mean follow-up time was 40.1 ± 23.2 (6-74) months. The balloon was postoperatively inflated on average with 11.6 ± 5.7 (5-25) mL. After the mean 40.1 months of follow-up, 16 of the 21 patients (76.2%) were dry (11 patients, 0 pads; 5 patients using safety pads), 3 patients (14%) had mild and 2 (9.8%) had moderate degree post-prostatectomy urinary incontinence (PPI). The average maximum urine flow rate of the patients was 15.6 ± 4.7 (10-31) mL/s. No residual urine was found. In 2 patients, all parts of the device were removed due to infection and discomfort, and in 3 patients only the inflation component was removed due to local scrotal infection. Our results show that using an adjustable perineal male sling with a tissue expander seems to be an efficient, and safe surgical treatment option in patients with PPI.

Tissue engineering, stem cells, and cloning for the regeneration of urologic organs.

PubMed

Atala, Anthony

2003-10-01

Tissue engineering efforts are currently being undertaken for every type of tissue and organ within the urinary system. Most of the effort expended to engineer genitourinary tissues has occurred within the last decade. Tissue engineering techniques require a cell culture facility designed for human application. Personnel who have mastered the techniques of cell harvest, culture, and expansion as well as polymer design are essential for the successful application of this technology. Various engineered genitourinary tissues are at different stages of development, with some already being used clinically, a few in preclinical trials, and some in the discovery stage. Recent progress suggests that engineered urologic tissues may have an expanded clinical applicability in the future.

Collective pulsatile expansion and swirls in proliferating tumor tissue

NASA Astrophysics Data System (ADS)

Yang, Taeseok Daniel; Kim, Hyun; Yoon, Changhyeong; Baek, Seung-Kuk; Lee, Kyoung J.

2016-10-01

Understanding the dynamics of expanding biological tissues is essential to a wide range of phenomena in morphogenesis, wound healing and tumor proliferation. Increasing evidence suggests that many of the relevant phenomena originate from complex collective dynamics, inherently nonlinear, of constituent cells that are physically active. Here, we investigate thin disk layers of proliferating, cohesive, monoclonal tumor cells and report the discovery of macroscopic, periodic, soliton-like mechanical waves with which cells are collectively ratcheting, as in the traveling-wave chemotaxis of dictyostelium discodium amoeba cells. The relevant length-scale of the waves is remarkably large (∼1 mm), compared to the thickness of a mono-layer tissue (∼ 10 μ {{m}}). During the tissue expansion, the waves are found to repeat several times with a quite well defined period of approximately 4 h. Our analyses suggest that the waves are initiated by the leading edge that actively pulls the tissue in the outward direction, while the cells within the bulk tissue do not seem to generate a strong self-propulsion. Subsequently, we demonstrate that a simple mathematical model chain of nonlinear springs that are constantly pulled in the outward direction at the leading edge recapitulates the observed phenomena well. As the areal cell density becomes too high, the tissue expansion stalls and the periodic traveling waves yield to multiple swirling vortices. Cancer cells are known to possess a broad spectrum of migration mechanisms. Yet, our finding has established a new unusual mode of tumor tissue expansion, and it may be equally applicable for many different expanding thin layers of cell tissues.

Comparison of Uncultured Marrow Mononuclear Cells and Culture-Expanded Mesenchymal Stem Cells in 3D Collagen-Chitosan Microbeads for Orthopedic Tissue Engineering

PubMed Central

Wise, Joel K.; Alford, Andrea I.; Goldstein, Steven A.

2014-01-01

Stem cell-based therapies have shown promise in enhancing repair of bone and cartilage. Marrow-derived mesenchymal stem cells (MSC) are typically expanded in vitro to increase cell number, but this process is lengthy, costly, and there is a risk of contamination and altered cellular properties. Potential advantages of using fresh uncultured bone marrow mononuclear cells (BMMC) include heterotypic cell and paracrine interactions between MSC and other marrow-derived cells including hematopoietic, endothelial, and other progenitor cells. In the present study, we compared the osteogenic and chondrogenic potential of freshly isolated BMMC to that of cultured-expanded MSC, when encapsulated in three-dimensional (3D) collagen-chitosan microbeads. The effect of low and high oxygen tension on cell function and differentiation into orthopedic lineages was also examined. Freshly isolated rat BMMC (25×106 cells/mL, containing an estimated 5×104 MSC/mL) or purified and culture-expanded rat bone marrow-derived MSC (2×105 cells/mL) were added to a 65–35 wt% collagen-chitosan hydrogel mixture and fabricated into 3D microbeads by emulsification and thermal gelation. Microbeads were cultured in control MSC growth media in either 20% O2 (normoxia) or 5% O2 (hypoxia) for an initial 3 days, and then in control, osteogenic, or chondrogenic media for an additional 21 days. Microbead preparations were evaluated for viability, total DNA content, calcium deposition, and osteocalcin and sulfated glycosaminoglycan expression, and they were examined histologically. Hypoxia enhanced initial progenitor cell survival in fresh BMMC-microbeads, but it did not enhance osteogenic potential. Fresh uncultured BMMC-microbeads showed a similar degree of osteogenesis as culture-expanded MSC-microbeads, even though they initially contained only 1/10th the number of MSC. Chondrogenic differentiation was not strongly supported in any of the microbead formulations. This study demonstrates the microbead-based approach to culturing and delivering cells for tissue regeneration, and suggests that fresh BMMC may be an alternative to using culture-expanded MSC for bone tissue engineering. PMID:23879621

Comparison of uncultured marrow mononuclear cells and culture-expanded mesenchymal stem cells in 3D collagen-chitosan microbeads for orthopedic tissue engineering.

PubMed

Wise, Joel K; Alford, Andrea I; Goldstein, Steven A; Stegemann, Jan P

2014-01-01

Stem cell-based therapies have shown promise in enhancing repair of bone and cartilage. Marrow-derived mesenchymal stem cells (MSC) are typically expanded in vitro to increase cell number, but this process is lengthy, costly, and there is a risk of contamination and altered cellular properties. Potential advantages of using fresh uncultured bone marrow mononuclear cells (BMMC) include heterotypic cell and paracrine interactions between MSC and other marrow-derived cells including hematopoietic, endothelial, and other progenitor cells. In the present study, we compared the osteogenic and chondrogenic potential of freshly isolated BMMC to that of cultured-expanded MSC, when encapsulated in three-dimensional (3D) collagen-chitosan microbeads. The effect of low and high oxygen tension on cell function and differentiation into orthopedic lineages was also examined. Freshly isolated rat BMMC (25 × 10(6) cells/mL, containing an estimated 5 × 10(4) MSC/mL) or purified and culture-expanded rat bone marrow-derived MSC (2 × 10(5) cells/mL) were added to a 65-35 wt% collagen-chitosan hydrogel mixture and fabricated into 3D microbeads by emulsification and thermal gelation. Microbeads were cultured in control MSC growth media in either 20% O2 (normoxia) or 5% O2 (hypoxia) for an initial 3 days, and then in control, osteogenic, or chondrogenic media for an additional 21 days. Microbead preparations were evaluated for viability, total DNA content, calcium deposition, and osteocalcin and sulfated glycosaminoglycan expression, and they were examined histologically. Hypoxia enhanced initial progenitor cell survival in fresh BMMC-microbeads, but it did not enhance osteogenic potential. Fresh uncultured BMMC-microbeads showed a similar degree of osteogenesis as culture-expanded MSC-microbeads, even though they initially contained only 1/10th the number of MSC. Chondrogenic differentiation was not strongly supported in any of the microbead formulations. This study demonstrates the microbead-based approach to culturing and delivering cells for tissue regeneration, and suggests that fresh BMMC may be an alternative to using culture-expanded MSC for bone tissue engineering.

Microgrid Controllers : Expanding Their Role and Evaluating Their Performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maitra, Arindam; Pratt, Annabelle; Hubert, Tanguy

Microgrids have long been deployed to provide power to customers in remote areas as well as critical industrial and military loads. Today, they are also being proposed as grid-interactive solutions for energy-resilient communities. Such microgrids will spend most of the time operating while synchronized with the surrounding utility grid but will also be capable of separating during contingency periods due to storms or temporary disturbances such as local grid faults. Properly designed and grid-integrated microgrids can provide the flexibility, reliability, and resiliency needs of both the future grid and critical customers. These systems can be an integral part of futuremore » power system designs that optimize investments to achieve operational goals, improved reliability, and diversification of energy sources.« less

Bacterial nanocellulose stimulates mesenchymal stem cell expansion and formation of stable collagen-I networks as a novel biomaterial in tissue engineering.

PubMed

Vielreicher, Martin; Kralisch, Dana; Völkl, Simon; Sternal, Fabian; Arkudas, Andreas; Friedrich, Oliver

2018-06-20

Biomimetic scaffolds are of great interest to tissue engineering (TE) and tissue repair as they support important cell functions. Scaffold coating with soluble collagen-I has been used to achieve better tissue integration in orthopaedy, however, as collagen persistence was only temporary such efforts were limited. Adequate coverage with cell-derived ECM collagen-I would promise great success, in particular for TE of mechanically challenged tissues. Here, we have used label-free, non-invasive multiphoton microscopy (MPM) to characterise bacterial nanocellulose (BNC) - a promising biomaterial for bone TE - and their potency to stimulate collagen-I formation by mesenchymal stem cells (MSCs). BNC fleeces were investigated by Second Harmonic Generation (SHG) imaging and by their characteristic autofluorescence (AF) pattern, here described for the first time. Seeded MSCs adhered fast, tight and very stable, grew to multilayers and formed characteristic, wide-spread and long-lasting collagen-I. MSCs used micron-sized lacunae and cracks on the BNC surface as cell niches. Detailed analysis using a collagen-I specific binding protein revealed a highly ordered collagen network structure at the cell-material interface. In addition, we have evidence that BNC is able to stimulate MSCs towards osteogenic differentiation. These findings offer new options for the development of engineered tissue constructs based on BNC.

Quantitative computed tomography determined regional lung mechanics in normal nonsmokers, normal smokers and metastatic sarcoma subjects.

PubMed

Choi, Jiwoong; Hoffman, Eric A; Lin, Ching-Long; Milhem, Mohammed M; Tessier, Jean; Newell, John D

2017-01-01

Extra-thoracic tumors send out pilot cells that attach to the pulmonary endothelium. We hypothesized that this could alter regional lung mechanics (tissue stiffening or accumulation of fluid and inflammatory cells) through interactions with host cells. We explored this with serial inspiratory computed tomography (CT) and image matching to assess regional changes in lung expansion. We retrospectively assessed 44 pairs of two serial CT scans on 21 sarcoma patients: 12 without lung metastases and 9 with lung metastases. For each subject, two or more serial inspiratory clinically-derived CT scans were retrospectively collected. Two research-derived control groups were included: 7 normal nonsmokers and 12 asymptomatic smokers with two inspiratory scans taken the same day or one year apart respectively. We performed image registration for local-to-local matching scans to baseline, and derived local expansion and density changes at an acinar scale. Welch two sample t test was used for comparison between groups. Statistical significance was determined with a p value < 0.05. Lung regions of metastatic sarcoma patients (but not the normal control group) demonstrated an increased proportion of normalized lung expansion between the first and second CT. These hyper-expanded regions were associated with, but not limited to, visible metastatic lung lesions. Compared with the normal control group, the percent of increased normalized hyper-expanded lung in sarcoma subjects was significantly increased (p < 0.05). There was also evidence of increased lung "tissue" volume (non-air components) in the hyper-expanded regions of the cancer subjects relative to non-hyper-expanded regions. "Tissue" volume increase was present in the hyper-expanded regions of metastatic and non-metastatic sarcoma subjects. This putatively could represent regional inflammation related to the presence of tumor pilot cell-host related interactions. This new quantitative CT (QCT) method for linking serial acquired inspiratory CT images may provide a diagnostic and prognostic means to objectively characterize regional responses in the lung following oncological treatment and monitoring for lung metastases.

32 CFR 147.30 - Temporary eligibility for access at the confidential and secret levels and temporary eligibility...

Code of Federal Regulations, 2013 CFR

2013-07-01

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32 CFR 147.30 - Temporary eligibility for access at the confidential and secret levels and temporary eligibility...

Code of Federal Regulations, 2012 CFR

2012-07-01

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32 CFR 147.30 - Temporary eligibility for access at the confidential and secret levels and temporary eligibility...

Code of Federal Regulations, 2010 CFR

2010-07-01

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32 CFR 147.30 - Temporary eligibility for access at the confidential and secret levels and temporary eligibility...

Code of Federal Regulations, 2011 CFR

2011-07-01

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Code of Federal Regulations, 2014 CFR

2014-07-01

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Ballistic fractures: indirect fracture to bone.

PubMed

Dougherty, Paul J; Sherman, Don; Dau, Nathan; Bir, Cynthia

2011-11-01

Two mechanisms of injury, the temporary cavity and the sonic wave, have been proposed to produce indirect fractures as a projectile passes nearby in tissue. The purpose of this study is to evaluate the temporal relationship of pressure waves using strain gauge technology and high-speed video to elucidate whether the sonic wave, the temporary cavity, or both are responsible for the formation of indirect fractures. Twenty-eight fresh frozen cadaveric diaphyseal tibia (2) and femurs (26) were implanted into ordnance gelatin blocks. Shots were fired using 9- and 5.56-mm bullets traversing through the gelatin only, passing close to the edge of the bone, but not touching, to produce an indirect fracture. High-speed video of the impact event was collected at 20,000 frames/s. Acquisition of the strain data were synchronized with the video at 20,000 Hz. The exact time of fracture was determined by analyzing and comparing the strain gauge output and video. Twenty-eight shots were fired, 2 with 9-mm bullets and 26 with 5.56-mm bullets. Eight indirect fractures that occurred were of a simple (oblique or wedge) pattern. Comparison of the average distance of the projectile from the bone was 9.68 mm (range, 3-20 mm) for fractured specimens and 15.15 mm (range, 7-28 mm) for nonfractured specimens (Student's t test, p = 0.036). In this study, indirect fractures were produced after passage of the projectile. Thus, the temporary cavity, not the sonic wave, was responsible for the indirect fractures.

Cryopreservation and in vitro culture of primary cell types from lung tissue of a stranded pygmy sperm whale (Kogia breviceps).

PubMed

Annalaura Mancia; Spyropoulos, Demetri D; McFee, Wayne E; Newton, Danforth A; Baatz, John E

2012-01-01

Current models for in vitro studies of tissue function and physiology, including responses to hypoxia or environmental toxins, are limited and rely heavily on standard 2-dimensional (2-D) cultures with immortalized murine or human cell lines. To develop a new more powerful model system, we have pursued methods to establish and expand cultures of primary lung cell types and reconstituted tissues from marine mammals. What little is known about the physiology of the deep-sea diving pygmy sperm whale (PSW), Kogia breviceps, comes primarily from stranding events that occur along the coast of the southeastern United States. Thus, development of a method for preserving live tissues and retrieving live cells from deceased stranded individuals was initiated. This report documents successful cryopreservation of PSW lung tissue. We established in vitro cultures of primary lung cell types from tissue fragments that had been cryopreserved several months earlier at the stranding event. Dissociation of cryopreserved lung tissues readily provides a variety of primary cell types that, to varying degrees, can be expanded and further studied/manipulated in cell culture. In addition, PSW-specific molecular markers have been developed that permitted the monitoring of fibroblast, alveolar type II, and vascular endothelial cell types. Reconstitution of 3-D cultures of lung tissues with these cell types is now underway. This novel system may facilitate the development of rare or disease-specific lung tissue models (e.g., to test causes of PSW stranding events and lead to improved treatments for pulmonary hypertension or reperfusion injury in humans). Also, the establishment of a "living" tissue bank biorepository for rare/endangered species could serve multiple purposes as surrogates for freshly isolated samples. Copyright © 2011 Elsevier Inc. All rights reserved.

Craniofacial Tissue Engineering by Stem Cells

PubMed Central

Mao, J.J.; Giannobile, W.V.; Helms, J.A.; Hollister, S.J.; Krebsbach, P.H.; Longaker, M.T.; Shi, S.

2008-01-01

Craniofacial tissue engineering promises the regeneration or de novo formation of dental, oral, and craniofacial structures lost to congenital anomalies, trauma, and diseases. Virtually all craniofacial structures are derivatives of mesenchymal cells. Mesenchymal stem cells are the offspring of mesenchymal cells following asymmetrical division, and reside in various craniofacial structures in the adult. Cells with characteristics of adult stem cells have been isolated from the dental pulp, the deciduous tooth, and the periodontium. Several craniofacial structures—such as the mandibular condyle, calvarial bone, cranial suture, and subcutaneous adipose tissue—have been engineered from mesenchymal stem cells, growth factor, and/or gene therapy approaches. As a departure from the reliance of current clinical practice on durable materials such as amalgam, composites, and metallic alloys, biological therapies utilize mesenchymal stem cells, delivered or internally recruited, to generate craniofacial structures in temporary scaffolding biomaterials. Craniofacial tissue engineering is likely to be realized in the foreseeable future, and represents an opportunity that dentistry cannot afford to miss. PMID:17062735

Cell migration through connective tissue in 3-D

NASA Astrophysics Data System (ADS)

Fabry, Ben

2008-03-01

A prerequisite for metastasis formation is the ability of tumor cells to invade and migrate through connective tissue. Four key components endow tumor cells with this ability: secretion of matrix-degrading enzymes, firm but temporary adhesion onto connective tissue fibers, contractile force generation, and rapid remodeling of cytoskeletal structures. Cell adhesion, contraction, and cytoskeletal remodeling are biomechanical parameter that can be measured on single cells using a panel of biophysical methods. We use 2-D and 3-D traction microscopy to measure contractile forces; magnetic tweezer microrheology to estimate adhesion strengths, cytoskeletal stiffness and molecular turn-over rates; and nanoscale particle tracking to measure cytoskeletal remodeling. On a wide range of tumor cell lines we could show that cell invasiveness correlates with increased expression of integrin adhesion receptors, increased contractile force generation, and increased speed of cytoskeletal reorganization. Each of those biomechanical parameters, however, varied considerably between cell lines of similar invasivity, suggesting that tumor cells employ multiple invasion strategies that cannot be unambiguously characterized using a single assay.

A novel gellan-PVA nanofibrous scaffold for skin tissue regeneration: Fabrication and characterization.

PubMed

Vashisth, Priya; Nikhil, Kumar; Roy, Partha; Pruthi, Parul A; Singh, Rajesh P; Pruthi, Vikas

2016-01-20

In this investigation, we have introduced novel electrospun gellan based nanofibers as a hydrophilic scaffolding material for skin tissue regeneration. These nanofibers were fabricated using a blend mixture of gellan with polyvinyl alcohol (PVA). PVA reduced the repulsive force of resulting solution and lead to formation of uniform fibers with improved nanostructure. Field emission scanning electron microscopy (FESEM) confirmed the average diameter of nanofibers down to 50 nm. The infrared spectra (IR), differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analysis evaluated the crosslinking, thermal stability and highly crystalline nature of gellan-PVA nanofibers, respectively. Furthermore, the cell culture studies using human dermal fibroblast (3T3L1) cells established that these gellan based nanofibrous scaffold could induce improved cell adhesion and enhanced cell growth than conventionally proposed gellan based hydrogels and dry films. Importantly, the nanofibrous scaffold are biodegradable and could be potentially used as a temporary substrate/or biomedical graft to induce skin tissue regeneration. Copyright © 2015 Elsevier Ltd. All rights reserved.

Immediate provisional restoration of a single-tooth implant in the esthetic zone: a case report.

PubMed

Fu, Po-Sung; Wu, Yi-Min; Tsai, Ching-Fang; Huang, Ta-Ko; Chen, Wen-Cheng; Hung, Chun-Cheng

2011-02-01

Immediate implant restoration of single implants may demonstrate a positive effect on peri-implant soft tissue. Placement of a provisional restoration following implant surgery can create soft tissue contours that resemble normal gingival topography before placement of the definitive prosthesis. This article describes a staged approach of the mandibular permanent right central incisor, which was congenital missing. The proper space for restoration of the missing incisor was created through orthodontic treatment. The scheduled implant site was reconstructed using autogenous bone harvested from the chin region. After a healing period of four months, an implant was installed with the connection of a fixed provisional crown to a prefabricated temporary abutment. The soft tissue around the implant healed according to the contours of the provisional restoration and the emergence profile was used to duplicate the definitive restoration. Peri-implant esthetics was achieved through the staged approach and immediate restoration of the implant. Copyright © 2011. Published by Elsevier B.V.

Method and apparatus for dynamic focusing of ultrasound energy

DOEpatents

Candy, James V.

2002-01-01

Method and system disclosed herein include noninvasively detecting, separating and destroying multiple masses (tumors, cysts, etc.) through a plurality of iterations from tissue (e.g., breast tissue). The method and system may open new frontiers with the implication of noninvasive treatment of masses in the biomedical area along with the expanding technology of acoustic surgery.

Biocompatibility of hydrogel-based scaffolds for tissue engineering applications.

PubMed

Naahidi, Sheva; Jafari, Mousa; Logan, Megan; Wang, Yujie; Yuan, Yongfang; Bae, Hojae; Dixon, Brian; Chen, P

2017-09-01

Recently, understanding of the extracellular matrix (ECM) has expanded rapidly due to the accessibility of cellular and molecular techniques and the growing potential and value for hydrogels in tissue engineering. The fabrication of hydrogel-based cellular scaffolds for the generation of bioengineered tissues has been based on knowledge of the composition and structure of ECM. Attempts at recreating ECM have used either naturally-derived ECM components or synthetic polymers with structural integrity derived from hydrogels. Due to their increasing use, their biocompatibility has been questioned since the use of these biomaterials needs to be effective and safe. It is not surprising then that the evaluation of biocompatibility of these types of biomaterials for regenerative and tissue engineering applications has been expanded from being primarily investigated in a laboratory setting to being applied in the multi-billion dollar medicinal industry. This review will aid in the improvement of design of non-invasive, smart hydrogels that can be utilized for tissue engineering and other biomedical applications. In this review, the biocompatibility of hydrogels and design criteria for fabricating effective scaffolds are examined. Examples of natural and synthetic hydrogels, their biocompatibility and use in tissue engineering are discussed. The merits and clinical complications of hydrogel scaffold use are also reviewed. The article concludes with a future outlook of the field of biocompatibility within the context of hydrogel-based scaffolds. Copyright © 2017 Elsevier Inc. All rights reserved.

Cross-sectional evaluation of the prevalence and factors associated with soft tissue scarring after the removal of miniscrews.

PubMed

Jung, Sung-ah; Choi, Yoon Jeong; Lee, Dong-Won; Kim, Kyung-Ho; Chung, Chooryung J

2015-05-01

To investigate the prevalence of distinguishable soft tissue scarring after the removal of temporary anchorage devices (TADs) such as orthodontic miniscrews and to analyze the factors associated with scar formation. The prevalence of soft tissue scarring in 66 patients (202 miniscrew removal sites) was clinically investigated at least 1 year after miniscrew removal. To determine the clinical factors associated with soft tissue scar formation, miniscrew stability; host factors including age, gender, and gingival biotype; and miniscrew-related factors such as insertion site, vertical position, and insertion period were evaluated. The prevalence of a distinguishable scar remaining at least 1 year after miniscrew removal was 44.6%. Patients with flat gingiva showed a significantly higher prevalence of soft tissue scar formation than did those with pronounced scalloped gingiva (P < .05). Maxillary buccal removal sites showed a significantly higher prevalence of soft tissue scar formation than did those in the mandible or palatal slope (P < .05). Miniscrew sites at the alveolar mucosa showed a significantly lower prevalence of soft tissue scar formation than did those in the mucogingival junction or the attached gingiva (P < .01). The prevalence of distinguishable scarring after miniscrew removal was fairly high. On the basis of our results, patients with flat gingiva and buccal interdental gingival insertion sites are more susceptible to scar formation.

A Clinical, Biological, and Biomaterials Perspective into Tendon Injuries and Regeneration

PubMed Central

Walden, Grace; Liao, Xin; Donell, Simon; Raxworthy, Mike J.; Riley, Graham P.

2017-01-01

Tendon injury is common and debilitating, and it is associated with long-term pain and ineffective healing. It is estimated to afflict 25% of the adult population and is often a career-ending disease in athletes and racehorses. Tendon injury is associated with high morbidity, pain, and long-term suffering for the patient. Due to the low cellularity and vascularity of tendon tissue, once damage has occurred, the repair process is slow and inefficient, resulting in mechanically, structurally, and functionally inferior tissue. Current treatment options focus on pain management, often being palliative and temporary and ending in reduced function. Most treatments available do not address the underlying cause of the disease and, as such, are often ineffective with variable results. The need for an advanced therapeutic that addresses the underlying pathology is evident. Tissue engineering and regenerative medicine is an emerging field that is aimed at stimulating the body's own repair system to produce de novo tissue through the use of factors such as cells, proteins, and genes that are delivered by a biomaterial scaffold. Successful tissue engineering strategies for tendon regeneration should be built on a foundation of understanding of the molecular and cellular composition of healthy compared with damaged tendon, and the inherent differences seen in the tissue after disease. This article presents a comprehensive clinical, biological, and biomaterials insight into tendon tissue engineering and regeneration toward more advanced therapeutics. PMID:27596929

Alternative therapies in management of leiomyomas.

PubMed

Patel, Amrita; Malik, Minnie; Britten, Joy; Cox, Jeris; Catherino, William H

2014-09-01

Leiomyomas are benign soft-tissue neoplasms that arise from smooth muscle. Relief of symptoms (abnormal uterine bleeding, pain, pressure) is the major goal in management of women with significant symptoms. For symptomatic myomas, hysterectomy is a definitive solution; however, there are emerging less-invasive options. Magnetic resonance imaging-guided focused ultrasound surgery, cryomyolysis, and temporary occlusion of the uterine arteries are treatment options that are minimally invasive interventions with the benefit of preserving the uterus. This review summarizes procedure techniques, eligibility, complications, and outcomes of these alternate therapies. Published by Elsevier Inc.

Description of a bacterium associated with redmouth disease of rainbow trout (Salmo gairdneri)

USGS Publications Warehouse

Ross, A.J.; Rucker, R.R.; Ewing, W.H.

1966-01-01

A description was given of a gram-negative, peritrichously flagellated, fermentative bacterium that was isolated on numerous occasions from kidney tissues of rainbow trout (Salmo gairdneri) afflicted with redmouth disease. Although the bacteria apparently were members of the family Enterobacteriaceae, it was impossible to determine their taxonomic position within the family with certainty. Hence it was recommended that their taxonomic position remain sub judice for the present. As a temporary designation RM bacterium was used. Redmouth disease was transmitted from infected to normal fish through the medium of water.

32 CFR 147.31 - Temporary eligibility for access at the top secret levels and temporary eligibility for “Q...

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 1 2011-07-01 2011-07-01 false Temporary eligibility for access at the top secret levels and temporary eligibility for âQâ access authorization: For someone who is the subject of a... Guidelines for Temporary Access § 147.31 Temporary eligibility for access at the top secret levels and...

32 CFR 147.31 - Temporary eligibility for access at the top secret levels and temporary eligibility for “Q...

Code of Federal Regulations, 2014 CFR

2014-07-01

... 32 National Defense 1 2014-07-01 2014-07-01 false Temporary eligibility for access at the top secret levels and temporary eligibility for âQâ access authorization: For someone who is the subject of a... Guidelines for Temporary Access § 147.31 Temporary eligibility for access at the top secret levels and...

32 CFR 147.31 - Temporary eligibility for access at the top secret levels and temporary eligibility for “Q...

Code of Federal Regulations, 2012 CFR

2012-07-01

... 32 National Defense 1 2012-07-01 2012-07-01 false Temporary eligibility for access at the top secret levels and temporary eligibility for âQâ access authorization: For someone who is the subject of a... Guidelines for Temporary Access § 147.31 Temporary eligibility for access at the top secret levels and...

32 CFR 147.31 - Temporary eligibility for access at the top secret levels and temporary eligibility for “Q...

Code of Federal Regulations, 2013 CFR

2013-07-01

... 32 National Defense 1 2013-07-01 2013-07-01 false Temporary eligibility for access at the top secret levels and temporary eligibility for âQâ access authorization: For someone who is the subject of a... Guidelines for Temporary Access § 147.31 Temporary eligibility for access at the top secret levels and...

32 CFR 147.31 - Temporary eligibility for access at the top secret levels and temporary eligibility for “Q...

Code of Federal Regulations, 2010 CFR

2010-07-01

... Guidelines for Temporary Access § 147.31 Temporary eligibility for access at the top secret levels and... 32 National Defense 1 2010-07-01 2010-07-01 false Temporary eligibility for access at the top secret levels and temporary eligibility for âQâ access authorization: For someone who is the subject of a...

Database construction for PromoterCAD: synthetic promoter design for mammals and plants.

PubMed

Nishikata, Koro; Cox, Robert Sidney; Shimoyama, Sayoko; Yoshida, Yuko; Matsui, Minami; Makita, Yuko; Toyoda, Tetsuro

2014-03-21

Synthetic promoters can control a gene's timing, location, and expression level. The PromoterCAD web server ( http://promotercad.org ) allows the design of synthetic promoters to control plant gene expression, by novel arrangement of cis-regulatory elements. Recently, we have expanded PromoterCAD's scope with additional plant and animal data: (1) PLACE (Plant Cis-acting Regulatory DNA Elements), including various sized sequence motifs; (2) PEDB (Mammalian Promoter/Enhancer Database), including gene expression data for mammalian tissues. The plant PromoterCAD data now contains 22 000 Arabidopsis thaliana genes, 2 200 000 microarray measurements in 20 growth conditions and 79 tissue organs and developmental stages, while the new mammalian PromoterCAD data contains 679 Mus musculus genes and 65 000 microarray measurements in 96 tissue organs and cell types ( http://promotercad.org/mammal/ ). This work presents step-by-step instructions for adding both regulatory motif and gene expression data to PromoterCAD, to illustrate how users can expand PromoterCAD functionality for their own applications and organisms.

Expanding the therapeutic use of androgens via selective androgen receptor modulators (SARMs)

PubMed Central

Gao, Wenqing; Dalton, James T.

2007-01-01

Selective androgen receptor modulators (SARMs) are a novel class of androgen receptor (AR) ligands that might change the future of androgen therapy dramatically. With improved pharmacokinetic characteristics and tissue-selective pharmacological activities, SARMs are expected to greatly extend the clinical applications of androgens to osteoporosis, muscle wasting, male contraception and diseases of the prostate. Mechanistic studies with currently available SARMs will help to define the contributions of differential tissue distribution, tissue-specific expression of 5α-reductase, ligand-specific regulation of gene expression and AR interactions with tissue-specific coactivators to their observed tissue selectivity, and lead to even greater expansion of selective anabolic therapies. PMID:17331889

Clinical evaluation of expanded mesh connective tissue graft in the treatment for multiple adjacent gingival recessions in the esthetic zone

PubMed Central

Shanmugam, M.; Shivakumar, B.; Meenapriya, B.; Anitha, V.; Ashwath, B.

2015-01-01

Background: Multiple approaches have been used to replace lost, damaged or diseased gingival tissues. The connective tissue graft (CTG) procedure is the golden standard method for root coverage. Although multiple sites often need grafting, the palatal mucosa supplies only a limited area of grafting material. To overcome this limitation, expanded mesh graft provides a method whereby a graft can be stretched to cover a large area. The aim of this study was to evaluate the effectiveness and the predictability of expanded mesh CTG (e-MCTG) in the treatment of adjacent multiple gingival recessions. Materials and Methods: Sixteen patients aged 20–50 years contributed to 55 sites, each site falling into at least three adjacent Miller's Class 1 or Class 2 gingival recession. The CTG obtained from the palatal mucosa was expanded to cover the recipient bed, which was 1.5 times larger than the graft. Clinical measurements were recorded at baseline and 3 months, 12 months postoperatively. Results: A mean coverage of 1.96 mm ± 0.66 mm and 2.22 mm ± 0.68 mm was obtained at the end of 3rd and 12th month, respectively. Twelve months after surgery a statistically significant increase in CAL (2.2 mm ± 0.68 mm, P < 0.001) and increasing WKT (1.75 ± 0.78, P < 0.001) were obtained. In 80% of the treated sites, 100% root coverage was achieved (mean 93.5%). Conclusions: The results of this study demonstrated that multiple adjacent recessions were treated by using e-MCTG technique can be applied and highly predictable root coverage can be achieved. PMID:26321829

Adipose-Derived Stromal Vascular Fraction Differentially Expands Breast Progenitors in Tissue Adjacent to Tumors Compared to Healthy Breast Tissue

PubMed Central

Chatterjee, Sumanta; Laliberte, Mike; Blelloch, Sarah; Ratanshi, Imran; Safneck, Janice; Buchel, Ed

2015-01-01

Background: Autologous fat grafts supplemented with adipose-derived stromal vascular fraction are used in reconstructive and cosmetic breast procedures. Stromal vascular fraction contains adipose-derived stem cells that are thought to encourage wound healing, tissue regeneration, and graft retention. Although use of stromal vascular fraction has provided exciting perspectives for aesthetic procedures, no studies have yet been conducted to determine whether its cells contribute to breast tissue regeneration. The authors examined the effect of these cells on the expansion of human breast epithelial progenitors. Methods: From patients undergoing reconstructive breast surgery following mastectomies, abdominal fat, matching tissue adjacent to breast tumors, and the contralateral non–tumor-containing breast tissue were obtained. Ex vivo co-cultures using breast epithelial cells and the stromal vascular fraction cells were used to study the expansion potential of breast progenitors. Breast reduction samples were collected as a source of healthy breast cells. Results: The authors observed that progenitors present in healthy breast tissue or contralateral non–tumor-containing breast tissue showed significant and robust expansion in the presence of stromal vascular fraction (5.2- and 4.8-fold, respectively). Whereas the healthy progenitors expanded up to 3-fold without the stromal vascular fraction cells, the expansion of tissue adjacent to breast tumor progenitors required the presence of stromal vascular fraction cells, leading to a 7-fold expansion, which was significantly higher than the expansion of healthy progenitors with stromal vascular fraction. Conclusions: The use of stromal vascular fraction might be more beneficial to reconstructive operations following mastectomies compared with cosmetic corrections of the healthy breast. Future studies are required to examine the potential risk factors associated with its use. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V. PMID:26090768

The use of balloon-expandable metallic stents in the treatment of pediatric tracheomalacia and bronchomalacia.

PubMed

Furman, R H; Backer, C L; Dunham, M E; Donaldson, J; Mavroudis, C; Holinger, L D

1999-02-01

To evaluate the use of balloon-expandable metallic stents in the treatment of children with tracheomalacia and bronchomalacia in whom conventional therapy has failed. Retrospective case series. Tertiary pediatric otolaryngology and cardiothoracic surgery referral center. Six patients were identified as having undergone bronchoscopic placement of metallic balloon-expandable stents between 1994 and 1997. The age at stent placement, prior surgical interventions, and indications for and sites of stent placement were noted. Also, the complications related to stent placement and the current airway status of the patients were reviewed. Twelve balloon-expandable metallic angioplasty stents (Palmaz; Johnson & Johnson Interventional Systems Co, Warren, NJ) were placed bronchoscopically in 6 patients. Six stents were placed in the lower trachea, and 6 were placed in the main bronchi. The stents were balloon expanded under fluoroscopic guidance. Discontinuation of mechanical ventilation. The age at stent placement ranged from 1.5 to 38 months (mean age at placement, 10 months). The indications for stent placement were (1) tracheomalacia or bronchomalacia, (2) pericardial patch or slide tracheoplasty failure, and (3) bronchomalacia caused by tetralogy of Fallot and large pulmonary arteries. The primary complication of stent placement was postoperative granulation tissue formation. One patient required the removal of 2 tracheal stents because of granulation tissue formation. There were 2 deaths in the series, 1 possibly related to stent placement. Four of the 6 patients were weaned from mechanical ventilation, and 3 experienced prolonged relief of airway obstruction. Metallic balloon-expandable stents are effective in relieving lower tracheomalacia and bronchomalacia in select patients. Only patients in whom conventional therapy has failed should be considered for stent placement.

42 CFR 438.706 - Special rules for temporary management.

Code of Federal Regulations, 2010 CFR

2010-10-01

... temporary management. (a) Optional imposition of sanction. The State may impose temporary management only if... sanction. The State must impose temporary management (regardless of any other sanction that may be imposed... right to terminate enrollment. (c) Hearing. The State may not delay imposition of temporary management...

42 CFR 488.415 - Temporary management.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 42 Public Health 5 2012-10-01 2012-10-01 false Temporary management. 488.415 Section 488.415... Compliance for Long-Term Care Facilities with Deficiencies § 488.415 Temporary management. (a) Definition. Temporary management means the temporary appointment by CMS or the State of a substitute facility manager or...

42 CFR 488.415 - Temporary management.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 42 Public Health 5 2014-10-01 2014-10-01 false Temporary management. 488.415 Section 488.415... Compliance for Long-Term Care Facilities with Deficiencies § 488.415 Temporary management. (a) Definition. Temporary management means the temporary appointment by CMS or the State of a substitute facility manager or...

42 CFR 488.415 - Temporary management.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 42 Public Health 5 2013-10-01 2013-10-01 false Temporary management. 488.415 Section 488.415... Compliance for Long-Term Care Facilities with Deficiencies § 488.415 Temporary management. (a) Definition. Temporary management means the temporary appointment by CMS or the State of a substitute facility manager or...

42 CFR 488.415 - Temporary management.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 42 Public Health 5 2011-10-01 2011-10-01 false Temporary management. 488.415 Section 488.415... Compliance for Long-Term Care Facilities with Deficiencies § 488.415 Temporary management. (a) Definition. Temporary management means the temporary appointment by CMS or the State of a substitute facility manager or...

5 CFR 213.3199 - Temporary organizations.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Temporary organizations. 213.3199 Section... SERVICE Excepted Schedules Schedule A § 213.3199 Temporary organizations. Positions on the staffs of temporary organizations, as defined in 5 U.S.C. 3161(a). Appointments may not exceed 3 years, but temporary...

48 CFR 37.112 - Government use of private sector temporaries.

Code of Federal Regulations, 2010 CFR

2010-10-01

... use of private sector temporaries. Contracting officers may enter into contracts with temporary help service firms for the brief or intermittent use of the skills of private sector temporaries. Services... part 300, subpart E, Use of Private Sector Temporaries, and agency procedures. [56 FR 55380, Oct. 25...

42 CFR 488.415 - Temporary management.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 42 Public Health 5 2010-10-01 2010-10-01 false Temporary management. 488.415 Section 488.415... Compliance for Long-Term Care Facilities with Deficiencies § 488.415 Temporary management. (a) Definition. Temporary management means the temporary appointment by CMS or the State of a substitute facility manager or...

38 CFR 60.7 - Duration of temporary lodging.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 2 2011-07-01 2011-07-01 false Duration of temporary lodging. 60.7 Section 60.7 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS (CONTINUED) FISHER HOUSES AND OTHER TEMPORARY LODGING § 60.7 Duration of temporary lodging. Temporary lodging...

8 CFR 244.14 - Withdrawal of Temporary Protected Status.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Withdrawal of Temporary Protected Status... TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 244.14 Withdrawal of Temporary Protected Status. (a) Authority of USCIS. USCIS may withdraw the status of an alien granted Temporary Protected...

8 CFR 244.14 - Withdrawal of Temporary Protected Status.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Withdrawal of Temporary Protected Status... TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 244.14 Withdrawal of Temporary Protected Status. (a) Authority of USCIS. USCIS may withdraw the status of an alien granted Temporary Protected...

8 CFR 244.14 - Withdrawal of Temporary Protected Status.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Withdrawal of Temporary Protected Status... TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 244.14 Withdrawal of Temporary Protected Status. (a) Authority of USCIS. USCIS may withdraw the status of an alien granted Temporary Protected...

Temporary employment and health: a review.

PubMed

Virtanen, Marianna; Kivimäki, Mika; Joensuu, Matti; Virtanen, Pekka; Elovainio, Marko; Vahtera, Jussi

2005-06-01

We aimed to review evidence on the relationship between temporary employment and health, and to see whether the association is dependent on outcome measure, instability of employment, and contextual factors. We systematically searched for studies of temporary employment and various health outcomes and critically appraised 27 studies. The review suggests higher psychological morbidity among temporary workers compared with permanent employees. According to some studies, temporary workers also have a higher risk of occupational injuries but their sickness absence is lower. Morbidity may be higher in temporary jobs with high employment instability and in countries with a lower number of temporary workers and unemployed workers. The evidence indicates an association between temporary employment and psychological morbidity. The health risk may depend on instability of temporary employment and the context. Confounding by occupation may have biased some of the studies. Additional research to clarify the role of employment instability, hazard accumulation, and selection is recommended.

Damage control and intramedullary nailing for long bone fractures in polytrauma patients.

PubMed

Patka, Peter

2017-06-01

The early fracture treatment in patients with multiple injuries should be focused on damage control. The fracture type and its location, local soft tissue condition as well as the patient's physiological condition shall determine the time and type of fracture treatment. Prevention of local and systemic complications must be immediately considered and included in the treatment planning. The use of external fixator (ExFix), which will be replaced by IM-implants in most cases at a later stage, provides adequate temporary fracture stabilization with less collateral damage. Good clinical results can be expected in patients with long bone fractures if the principles of damage control surgery are applied and local complications are prevented through proper reduction, firm fixation, early soft tissue reconstruction, and early rehabilitation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Mobile clinics for antiretroviral therapy in rural Mozambique

PubMed Central

Jequicene, Tito; Blevins, Meridith; José, Eurico; Lankford, Julie R; Wester, C William; Fuchs, Martina C; Vermund, Sten H

2014-01-01

Abstract Problem Despite seven years of investment from the President's Emergency Plan For AIDS Relief (PEPFAR), the expansion of human immunodeficiency virus (HIV)-related services continues to challenge Mozambique’s health-care infrastructure, especially in the country’s rural regions. Approach In 2012, as part of a national acceleration plan for HIV care and treatment, Namacurra district employed a mobile clinic strategy to provide temporary manpower and physical space to expand services at four rural peripheral clinics. This paper describes the strategy deployed, the uptake of services and the key lessons learnt in the first 18 months of implementation. Local setting In 2012, Namacurra´s adult population was estimated to be 125 425, and of those 15 803 were estimated to be HIV infected. Although there is consistent government support of antiretroviral therapy (ART) programmes, national coverage remains low, with less than 15% of those eligible having received ART by December 2012. Relevant changes Between April 2012 and September 2013, Namacurra district enrolled 4832 new patients into HIV care and treatment. By using the mobile clinic strategy for ART expansion, the district was able to expand provision of ART from two to six (of a desired seven) clinics by September 2013. Lessons learnt Mobile clinic strategies could rapidly expand HIV care and treatment in under-funded settings in ways that both build local capacity and are sustainable for local health systems. The clinics best serve as a transition to improved capacity at fixed-site services. PMID:25378759

Outcomes of secondary self-expandable metal stents versus surgery after delayed initial palliative stent failure in malignant colorectal obstruction.

PubMed

Yoon, Jin Young; Park, Soo Jung; Hong, Sung Pil; Kim, Tae Il; Kim, Won Ho; Cheon, Jae Hee

2013-01-01

When re-intervention is required due to an occluded first colorectal self-expanding metal stent for malignant colorectal obstruction, serious controversies exist regarding whether to use endoscopic re-stenting or surgery. To compare the clinical outcomes in patients who underwent stent re-insertion versus palliative surgery as a second intervention. A total of 115 patients who received either self-expandable metal stent (SEMS) insertion or palliative surgery for treatment of a second occurrence of malignant colorectal obstruction after the first SEMS placement were retrospectively studied between July 2005 and December 2009. The median overall survival (8.2 vs. 15.5 months) and progression-free survival (4.0 vs. 2.7 months) were not significantly different between the stent and surgery groups (p = 0.895 and 0.650, respectively). The median lumen patency in the stent group was 3.4 months and that in the surgery group was 7.9 months (p = 0.003). The immediate complication rate after second stent insertion was 13.9% and late complication rate was observed in 12 of 79 (15.2%) patients. There was no mortality related to the SEMS procedure. The complication and mortality rates associated with palliative surgery were 3.5% (2/57) and 12.3% (7/57), respectively. Although there is no significant difference in the overall survival between stenting and surgery, a secondary stent insertion had a lower mortality rate despite a shorter duration of temporary colorectal decompression compared to that of palliative surgery.

Generation, cryopreservation, function and in vivo persistence of ex-vivo expanded cynomolgus monkey regulatory T cells

PubMed Central

Guo, Hao; Zhang, Hong; Lu, Lien; Ezzelarab, Mohamed B.; Thomson, Angus W.

2015-01-01

We expanded flow-sorted Foxp3+ cynomolgus monkey regulatory T cells (Treg) >1000-fold after three rounds of stimulation with anti-CD3 mAb-loaded artificial antigen-presenting cells, rapamycin (first round only) and IL-2. The expanded Treg maintained their expression of Treg signature markers, CD25, CD27, CD39, Foxp3, Helios, and CTLA-4, as well as CXCR3, which plays an important role in T cell migration to sites of inflammation. In contrast to expanded effector T cells (Teff), expanded Treg produced minimal IFN-γ and IL-17 and no IL-2 and potently suppressed Teff proliferation. Following cryopreservation, thawed Treg were less viable than their freshly-expanded counterparts, although no significant changes in phenotype or suppressive ability were observed. Additional rounds of stimulation/expansion restored maximal viability. Furthermore, adoptively-transferred autologous Treg expanded from cryopreserved second round stocks and labeled with CFSE or VPD450 were detected in blood and secondary lymphoid tissues of normal or immunosuppressed recipients at least two months after their systemic infusion. PMID:25732601

School interventions after the Joplin tornado.

PubMed

Kanter, Robert K; Abramson, David

2014-04-01

To qualitatively describe interventions by schools to meet children's needs after the May 2011 Joplin, Missouri tornado. Qualitative exploratory study conducted six months after the tornado. Key informant interviews with school staff (teachers, psychologists, guidance counselor, nurse, principal), public health official, and physicians. After the tornado, school staff immediately worked to contact every enrolled child to provide assistance and coordinate recovery services. Despite severe damage to half of the city's schools, the decision was made to reopen schools at the earliest possible time to provide a safe, reassuring environment and additional services. An expanded summer school session emphasized child safety and emotional wellbeing. The 2011-2012 school year began on time, less than three months after the disaster, using temporary facilities. Displaced children were bused to their usual schools regardless of their new temporary residence locations. In just-in-time training sessions, teachers developed strategies to support students and staff experiencing anxiety or depression. Certified counselors conducted school-based, small-group counseling for students. Selective referrals were made to community mental health providers for children with greatest needs. Evidence from Joplin adds to a small body of empirical experience demonstrating the important contribution of schools to postdisaster community recovery. Despite timely and proactive services, many families and children struggled after the tornado. Improvements in the effectiveness of postdisaster interventions at schools will follow from future scientific evidence on optimal approaches.

Making an impact: an adventure into international pharmacy.

PubMed

Hitch, William; Ransom, Matthew

2009-01-01

To support a medical team, organized by Shoulder to Shoulder, with pharmacy services in an effort to expand ongoing health care to a rural community in Honduras. Pharmacy services in a temporary medical clinic in a schoolhouse in Colomarigua, a small mountain village in Honduras. Pharmacy services and medical care to address acute care needs of the people of Colomarigua, Honduras, during a week-long clinic. Interpreters assisted with patient counseling. Medication labels with pictures that connected doses to mealtimes increased patient understanding and the potential for medications to be dosed correctly. Fill lines were drawn on delivery devices for pediatric suspensions. An effort was made to avoid polypharmacy by communicating with physicians about the different prescriptions that were being prescribed in each household. Not applicable. Not applicable. We created a temporary clinic with a pharmacy and provided medical care to more than 600 children and adults in the surrounding regions. The medical team identified need for a feeding program, and local Shoulder to Shoulder teams began activities to support the community's development. Education programs were initiated to allow promising local children access to higher education. Challenges to providing optimal pharmaceutical care included language barriers, space and flow of the pharmacy, and a limited formulary. Benefits included gaining a whole new perspective on pharmacotherapy, health, and the importance of service to those in need whether abroad or at home.

8 CFR 215.9 - Temporary Worker Visa Exit Program.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Temporary Worker Visa Exit Program. 215.9... ALIENS DEPARTING FROM THE UNITED STATES § 215.9 Temporary Worker Visa Exit Program. An alien admitted on certain temporary worker visas at a port of entry participating in the Temporary Worker Visa Exit Program...

8 CFR 215.9 - Temporary Worker Visa Exit Program.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Temporary Worker Visa Exit Program. 215.9... ALIENS DEPARTING FROM THE UNITED STATES § 215.9 Temporary Worker Visa Exit Program. An alien admitted on certain temporary worker visas at a port of entry participating in the Temporary Worker Visa Exit Program...

8 CFR 215.9 - Temporary Worker Visa Exit Program.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Temporary Worker Visa Exit Program. 215.9... ALIENS DEPARTING FROM THE UNITED STATES § 215.9 Temporary Worker Visa Exit Program. An alien admitted on certain temporary worker visas at a port of entry participating in the Temporary Worker Visa Exit Program...

8 CFR 215.9 - Temporary Worker Visa Exit Program.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Temporary Worker Visa Exit Program. 215.9... ALIENS DEPARTING FROM THE UNITED STATES § 215.9 Temporary Worker Visa Exit Program. An alien admitted on certain temporary worker visas at a port of entry participating in the Temporary Worker Visa Exit Program...

8 CFR 215.9 - Temporary Worker Visa Exit Program.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Temporary Worker Visa Exit Program. 215.9... ALIENS DEPARTING FROM THE UNITED STATES § 215.9 Temporary Worker Visa Exit Program. An alien admitted on certain temporary worker visas at a port of entry participating in the Temporary Worker Visa Exit Program...

Directly auto-transplanted mesenchymal stem cells induce bone formation in a ceramic bone substitute in an ectopic sheep model

PubMed Central

Boos, Anja M; Loew, Johanna S; Deschler, Gloria; Arkudas, Andreas; Bleiziffer, Oliver; Gulle, Heinz; Dragu, Adrian; Kneser, Ulrich; Horch, Raymund E; Beier, Justus P

2011-01-01

Abstract Bone tissue engineering approaches increasingly focus on the use of mesenchymal stem cells (MSC). In most animal transplantation models MSC are isolated and expanded before auto cell transplantation which might be critical for clinical application in the future. Hence this study compares the potential of directly auto-transplanted versus in vitro expanded MSC with or without bone morphogenetic protein-2 (BMP-2) to induce bone formation in a large volume ceramic bone substitute in the sheep model. MSC were isolated from bone marrow aspirates and directly auto-transplanted or expanded in vitro and characterized using fluorescence activated cell sorting (FACS) and RT-PCR analysis before subcutaneous implantation in combination with BMP-2 and β-tricalcium phosphate/hydroxyapatite (β-TCP/HA) granules. Constructs were explanted after 1 to 12 weeks followed by histological and RT-PCR evaluation. Sheep MSC were CD29+, CD44+ and CD166+ after selection by Ficoll gradient centrifugation, while directly auto-transplanted MSC-populations expressed CD29 and CD166 at lower levels. Both, directly auto-transplanted and expanded MSC, were constantly proliferating and had a decreasing apoptosis over time in vivo. Directly auto-transplanted MSC led to de novo bone formation in a heterotopic sheep model using a β-TCP/HA matrix comparable to the application of 60 μg/ml BMP-2 only or implantation of expanded MSC. Bone matrix proteins were up-regulated in constructs following direct auto-transplantation and in expanded MSC as well as in BMP-2 constructs. Up-regulation was detected using immunohistology methods and RT-PCR. Dense vascularization was demonstrated by CD31 immunohistology staining in all three groups. Ectopic bone could be generated using directly auto-transplanted or expanded MSC with β-TCP/HA granules alone. Hence BMP-2 stimulation might become dispensable in the future, thus providing an attractive, clinically feasible approach to bone tissue engineering. PMID:20636333

High performance shape memory polymer networks based on rigid nanoparticle cores

PubMed Central

Song, Jie

2010-01-01

Smart materials that can respond to external stimuli are of widespread interest in biomedical science. Thermal-responsive shape memory polymers, a class of intelligent materials that can be fixed at a temporary shape below their transition temperature (Ttrans) and thermally triggered to resume their original shapes on demand, hold great potential as minimally invasive self-fitting tissue scaffolds or implants. The intrinsic mechanism for shape memory behavior of polymers is the freezing and activation of the long-range motion of polymer chain segments below and above Ttrans, respectively. Both Ttrans and the extent of polymer chain participation in effective elastic deformation and recovery are determined by the network composition and structure, which are also defining factors for their mechanical properties, degradability, and bioactivities. Such complexity has made it extremely challenging to achieve the ideal combination of a Ttrans slightly above physiological temperature, rapid and complete recovery, and suitable mechanical and biological properties for clinical applications. Here we report a shape memory polymer network constructed from a polyhedral oligomeric silsesquioxane nanoparticle core functionalized with eight polyester arms. The cross-linked networks comprising this macromer possessed a gigapascal-storage modulus at body temperature and a Ttrans between 42 and 48 °C. The materials could stably hold their temporary shapes for > 1 year at room temperature and achieve full shape recovery ≤ 51 °C in a matter of seconds. Their versatile structures allowed for tunable biodegradability and biofunctionalizability. These materials have tremendous promise for tissue engineering applications. PMID:20375285

Tissue expansion in the treatment of pressure ulcers.

PubMed

Esposito, G; Di Caprio, G; Ziccardi, P; Scuderi, N

1991-03-01

The authors report their experience using skin expanders in 11 patients with severe bed sores. The expanders, with different volumes, from 250 to 1000 cc, were generally overfilled using the cutaneous tonometer. In fact, with the information revealed by this apparatus on the skin in expansion, the authors were able to reduce the filling intervals without risking ulceration. In their experience, the results obtained were satisfactory: All patients treated achieved surgical recovery. The authors see a wide future for skin-expander use in pressure-ulcer treatment. They have a working hypothesis about using expanders to progressively advance sensitive skin in areas subject to ulceration. This hypothesis is based on the possibility of reexpanding the same flap several times, as has been seen in the treatment of other types of pathology.

Implementation of the Provision of the Comprehensive Addiction and Recovery Act of 2016 Relating to the Dispensing of Narcotic Drugs for Opioid Use Disorder. Final rule.

PubMed

2018-01-23

The Comprehensive Addiction and Recovery Act (CARA) of 2016, which became law on July 22, 2016, amended the Controlled Substances Act (CSA) to expand the categories of practitioners who may, under certain conditions on a temporary basis, dispense a narcotic drug in Schedule III, IV, or V for the purpose of maintenance treatment or detoxification treatment. Separately, the Department of Health and Human Services, by final rule effective August 8, 2016, increased to 275 the maximum number of patients that a practitioner may treat for opioid use disorder without being separately registered under the CSA for that purpose. The Drug Enforcement Administration (DEA) is hereby amending its regulations to incorporate these statutory and regulatory changes.

[Stages of kinetotherapy and therapeutic massage for long time bedridden patients].

PubMed

Murashko, N K

2012-01-01

Rehabilitation of stroke patients, is a complex chain of consistently conducted medical and social measures aimed at rehabilitation, health or possible adaptation to self-service in the presence of a persistent neurological defect. Already in acute stroke patient needs not only to drug therapy and care, but also in the emotional and psychological support for the type of "cautious optimism." It should be explained to the patient a temporary, reversible nature of its existing motor and other violations. With relatives patient should discuss the real situation, prognosis, rehabilitation opportunities, the need for hospitalization or appropriate treatment at home, put them in front of clear objectives for the near future. Activity and the amount of rehabilitation expanded in young children with satisfactory prognosis, consideration being given to their professional and social status.

76 FR 1261 - Establishment of the Permanent Certification Program for Health Information Technology

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-07

...This final rule establishes a permanent certification program for the purpose of certifying health information technology (HIT). This final rule is issued pursuant to the authority granted to the National Coordinator for Health Information Technology (the National Coordinator) by section 3001(c)(5) of the Public Health Service Act (PHSA), as added by the Health Information Technology for Economic and Clinical Health (HITECH) Act. The permanent certification program will eventually replace the temporary certification program that was previously established by a final rule. The National Coordinator will use the permanent certification program to authorize organizations to certify electronic health record (EHR) technology, such as Complete EHRs and/or EHR Modules. The permanent certification program could also be expanded to include the certification of other types of HIT.

CELLULAR CONTROL OF CONNECTIVE TISSUE MATRIX TENSION†

PubMed Central

Langevin, Helene M.; Nedergaard, Maiken; Howe, Alan

2013-01-01

The biomechanical behavior of connective tissue in response to stretching is generally attributed to the molecular composition and organization of its extracellular matrix. It also is becoming apparent that fibroblasts play an active role in regulating connective tissue tension. In response to static stretching of the tissue, fibroblasts expand within minutes by actively remodeling their cytoskeleton. This dynamic change in fibroblast shape contributes to the drop in tissue tension that occurs during viscoelastic relaxation. We propose that this response of fibroblasts plays a role in regulating extracellular fluid flow into the tissue, and protects against swelling when the matrix is stretched. This article reviews the evidence supporting possible mechanisms underlying this response including autocrine purinergic signaling. We also discuss fibroblast regulation of connective tissue tension with respect to lymphatic flow, immune function and cancer. PMID:23444198

In vivo imaging of tissue scattering parameter and cerebral hemodynamics in rat brain with a digital red-green-blue camera

NASA Astrophysics Data System (ADS)

Nishidate, Izumi; Mustari, Afrina; Kawauchi, Satoko; Sato, Shunichi; Sato, Manabu; Kokubo, Yasuaki

2017-02-01

We propose a rapid imaging method to monitor the spatial distribution of total hemoglobin concentration (CHbT), the tissue oxygen saturation, and the scattering power b in the expression of μs'=aλ-b as the scattering parameters in cerebral cortex using a digital red-green-blue camera. In the method, the RGB-values are converted into the tristimulus values in CIEXYZ color space which is compatible with the common RGB working spaces. Monte Carlo simulation (MCS) for light transport in tissue is used to specify a relation among the tristimulus XYZ-values and the concentration of oxygenated hemoglobin, that of deoxygenated hemoglobin, and the scattering power b. In the present study, we performed sequential recordings of RGB images of in vivo exposed rat brain during the cortical spreading depolarization evoked by the topical application of KCl. Changes in the total hemoglobin concentration and the tissue oxygen saturation imply the temporary change in cerebral blood flow during CSD. Decrease in the scattering power b was observed before the profound increase in the total hemoglobin concentration, which is indicative of the reversible morphological changes in brain tissue during CSD. The results in this study indicate potential of the method to evaluate the pathophysiological conditions in brain tissue with a digital red-green-blue camera.

Skin allograft and vascularized composite allograft: potential for long-term efficacy in the context of lymphatic modulation.

PubMed

Rinkinen, Jacob; Selley, Ryan; Agarwal, Shailesh; Loder, Shawn; Levi, Benjamin

2014-01-01

Tissue transplantation restores form and function in burn patients. The treatment of burn injuries is influenced by severity, location, and the percentage of total body surface area. There have been a number of different techniques developed to temporize and repair the destroyed tissue. However, in patients with large wound burden, sufficient donor site tissue may not be available for autograft harvesting. Such extensive burns necessitate other temporary and permanent options for wound coverage such as skin or vascularized composite allografts (VCA). Rejection of these tissues presents an ongoing problem which is currently managed using a host of systemic immunosuppressive medications. This article discusses the mechanism behind the innate and adaptive immune systems rejection of the allografts. By understanding these pathways, various techniques using immunomodulatory protocols have led to increased allograft survival. However, our primary interest lies in the initial recognition of the graft. We tailor this article to have a specific emphasis on lymphatic modulation as a potential adjunctive therapy. Reviews of the studies evaluating the effect of lymph node modulation on graft survival are described with future implications to allograft transplant research.

Growing skin: Tissue expansion in pediatric forehead reconstruction

PubMed Central

Zollner, Alexander M.; Buganza Tepole, Adrian; Gosain, Arun K.; Kuhl, Ellen

2011-01-01

Tissue expansion is a common surgical procedure to grow extra skin through controlled mechanical over-stretch. It creates skin that matches the color, texture, and thickness of the surrounding tissue, while minimizing scars and risk of rejection. Despite intense research in tissue expansion and skin growth, there is a clear knowledge gap between heuristic observation and mechanistic understanding of the key phenomena that drive the growth process. Here, we show that a continuum mechanics approach, embedded in a custom-designed finite element model, informed by medical imaging, provides valuable insight into the biomechanics of skin growth. In particular, we model skin growth using the concept of an incompatible growth configuration. We characterize its evolution in time using a second-order growth tensor parameterized in terms of a scalar-valued internal variable, the in-plane area growth. When stretched beyond the physiological level, new skin is created, and the in-plane area growth increases. For the first time, we simulate tissue expansion on a patient-specific geometric model, and predict stress, strain, and area gain at three expanded locations in a pediatric skull: in the scalp, in the forehead, and in the cheek. Our results may help the surgeon to prevent tissue over-stretch and make informed decisions about expander geometry, size, placement, and inflation. We anticipate our study to open new avenues in reconstructive surgery, and enhance treatment for patients with birth defects, burn injuries, or breast tumor removal. PMID:22052000

Comparative study of the optical properties of colon mucosa and colon precancerous polyps between 400 and 1000 nm

NASA Astrophysics Data System (ADS)

Carvalho, Sónia; Gueiral, Nuno; Nogueira, Elisabete; Henrique, Rui; Oliveira, Luís.; Tuchin, Valery V.

2017-03-01

Optical properties of biological tissues are unique and may be used for tissue identification, tissue discrimination or even to identify pathologies. Early stage colorectal cancer evolves from adenomatous polyps that arise in the inner layer of the colorectal tube - the mucosa. The identification of different optical properties between healthy and pathological colorectal tissues might be used to identify different tissue components and to develop an early stage diagnosis method using optical technologies. Since most of the biomedical optics techniques use light within the visible and near infrared wavelength ranges, we used the inverse adding-doubling method to make a fast estimation of the optical properties of colorectal mucosa and early stage adenocarcinoma between 400 and 1000 nm. The estimated wavelength dependencies have provided information about higher lipid content in healthy mucosa and higher blood content in pathological tissue. Such data has also indicated that the wavelength dependence of the scattering coefficient for healthy mucosa is dominated by Rayleigh scattering and for pathological mucosa it is dominated by Mie scattering. Such difference indicates smaller scatterer size in healthy mucosa tissue. Such information can now be used to develop new diagnosis or treatment methods for early cancer detection or removal. One possibility is to use optical clearing technique to improve tissue transparency and create localized and temporary tissue dehydration for image contrast improvement during diagnosis or polyp laser removal. Such techniques can now be developed based on the different results that we have found for healthy and pathological colorectal mucosa.

Proanthocyanidin: a natural crosslinking reagent for stabilizing collagen matrices.

PubMed

Han, Bo; Jaurequi, Jason; Tang, Bao Wei; Nimni, Marcel E

2003-04-01

While attempting to find a suitable crosslinking reagent for biopolymers, a naturally occurring proanthocyanidin (PA) obtained from grape seeds was selected to fix biological tissues. The cytotoxicity and crosslinking rate, reflected by the in vitro and in vivo degradation of fixed matrices has been studied. The shrinkage temperature of the fixed bovine pericardium increased from 66 to 86 degrees C. A cytotoxicity assay using fibroblast cultures revealed that PA is approximately 120 times less toxic than glutaraldehyde (GA), a currently used tissue stabilizer. In vitro degradation studies showed that fixed tissue was resistant to digestion by bacterial collagenase. Crosslinks between PA and tissues can be stabilized by decreasing the dielectric constant of the solution during storage. After subcutaneous implantation for periods ranging between 3 and 6 weeks, we found no apparent degradation of the GA- or PA-fixed tissues, whereas fresh tissue controls rapidly disintegrated. Beyond 6 weeks PA crosslinks began to degrade. More fibroblasts migrated and proliferated inside the PA-fixed implants compared with GA counterparts. Tissues crosslinked with PA manifested an enhanced collagen expression and deposition and did not calcify after implantation. GA, on the other hand, even after thorough rinsing continued to be cytotoxic, inhibited collagen synthesis and encouraged dystrophic calcification. Collagen matrices crosslinked with PA are expected to be of value in the design of matrices that will encourage cell ingrowth and proliferation, which are temporary in nature, and that are intended to regenerate or replace missing tissues, which can delay the biogradation of collagen. As such they should be of significant value in the emerging field of tissue engineering. Copyright 2003 Wiley Periodicals, Inc.

Catheter Insertion Reference Trajectory Construction Method Using Photoelastic Stress Analysis for Quantification of Respect for Tissue During Endovascular Surgery Simulation

NASA Astrophysics Data System (ADS)

Tercero, Carlos; Ikeda, Seiichi; Fukuda, Toshio; Arai, Fumihito; Negoro, Makoto; Takahashi, Ikuo

2011-10-01

There is a need to develop quantitative evaluation for simulator based training in medicine. Photoelastic stress analysis can be used in human tissue modeling materials; this enables the development of simulators that measure respect for tissue. For applying this to endovascular surgery, first we present a model of saccular aneurism where stress variation during micro-coils deployment is measured, and then relying on a bi-planar vision system we measure a catheter trajectory and compare it to a reference trajectory considering respect for tissue. New photoelastic tissue modeling materials will expand the applications of this technology to other medical training domains.

Selective Internal Radiotherapy (SIRT) of Hepatic Tumors: How to Deal with the Cystic Artery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Theysohn, Jens M., E-mail: jens.theysohn@uni-due.de; Mueller, Stefan; Schlaak, Joerg F.

2013-08-01

PurposeSelective internal radiotherapy (SIRT) with the beta emitter yttrium-90 (Y90) is a rapidly developing therapy option for unresectable liver malignancies. Nontarget irradiation of the gallbladder is a complication of SIRT. Thus, we aimed to assess different strategies to avoid infusion of Y90 into the cystic artery (CA).MethodsAfter hepatic digital subtraction angiography and administration of technetium-99m-labeled human serum albumin ({sup 99}mTc-HSA), 295 patients with primary or secondary liver tumors underwent single-photon emission computed tomography/computed tomography (SPECT/CT). Different measures were taken before repeated Y90 mapping and SIRT to avoid unintended influx into the CA where necessary. Clinical symptoms, including pain, fever, ormore » a positive Murphy sign, were assessed during patient follow-up.ResultsA significant {sup 99}mTc-HSA accumulation in the gallbladder wall (higher {sup 99}mTc-HSA uptake than in normal liver tissue) was seen in 20 patients. The following measures were taken to avoid unintended influx into the CA: temporary/permanent occlusion of the CA with gelfoam (n = 5)/microcoil (n = 1), induction of vasospasm with a microwire (n = 4), or altering catheter position (n = 10). Clinical signs of cholecystitis were observed in only one patient after temporary CA occlusion with gelfoam and were successfully treated by antibiotics. Cholecystectomy was not required for any patient.ConclusionIt is important to identify possible nontarget irradiation of the gallbladder. The risk for radiation-induced cholecystitis can be easily minimized by temporary or permanent CA embolization, vasospasm induction, or altering the catheter position.« less

Microcontact printing of polydopamine on thermally expandable hydrogels for controlled cell adhesion and delivery of geometrically defined microtissues.

PubMed

Lee, Yu Bin; Kim, Se-Jeong; Kim, Eum Mi; Byun, Hayeon; Chang, Hyung-Kwan; Park, Jungyul; Choi, Yu Suk; Shin, Heungsoo

2017-10-01

Scaffold-free harvest of microtissue with a defined structure has received a great deal of interest in cell-based assay and regenerative medicine. In this study, we developed thermally expandable hydrogels with spatially controlled cell adhesive patterns for rapid harvest of geometrically controlled microtissue. We patterned polydopamine (PD) on to the hydrogel via microcontact printing (μCP), in linear shapes with widths of 50, 100 and 200μm. The hydrogels facilitated formation of spatially controlled strip-like microtissue of human dermal fibroblasts (HDFBs). It was possible to harvest and translocate microtissues with controlled widths of 61.4±14.7, 104.3±15.6, and 186.6±22.3μm from the hydrogel to glass substrates by conformal contact upon expansion of the hydrogel in response to a temperature change from 37 to 4°C, preserving high viability, extracellular matrix, and junction proteins. Microtissues were readily translocated in vivo to the subcutaneous tissue of mouse. The microtissues were further utilized as a simple assay model for monitoring of contraction in response to ROCK1 inhibitor. Collectively, micro-sized patterning of PD on the thermally expandable hydrogels via μCP holds promise for the development of microtissue harvesting systems that can be employed to ex vivo tissue assay and cell-based therapy. Harvest of artificial tissue with controlled cellular arrangement independently from external materials has been widely studied in cell-based assay and regenerative medicine. In this study, we developed scaffold-free harvest system of microtissues with anisotropic arrangement and controlled width by exploiting thermally expandable hydrogels with cell-adhesive patterns of polydopamine formed by simple microcontact printing. Cultured strips of human dermal fibroblasts on the hydrogels were rapidly delivered to various targets ranging from flat coverglass to mice subcutaneous tissue by thermal expansion of the hydrogel at 4°C for 10min. These were further utilized as a drug screening model responding to ROCK1 inhibitor, which imply its versatile applicability. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Chondrogenically primed tonsil-derived mesenchymal stem cells encapsulated in riboflavin-induced photocrosslinking collagen-hyaluronic acid hydrogel for meniscus tissue repairs.

PubMed

Koh, Rachel H; Jin, Yinji; Kang, Byung-Jae; Hwang, Nathaniel S

2017-04-15

Current meniscus tissue repairing strategies involve partial or total meniscectomy, followed by allograft transplantation or synthetic material implantation. However, allografts and synthetic implants have major drawbacks such as the limited supply of grafts and lack of integration into host tissue, respectively. In this study, we investigated the effects of conditioned medium (CM) from meniscal fibrochondrocytes and TGF-β3 on tonsil-derived mesenchymal stem cells (T-MSCs) for meniscus tissue engineering. CM-expanded T-MSCs were encapsulated in riboflavin-induced photocrosslinked collagen-hyaluronic acid (COL-RF-HA) hydrogels and cultured in chondrogenic medium containing TGF-β3. In vitro results indicate that CM-expanded cells followed by TGF-β3 exposure stimulated the expression of fibrocartilage-related genes (COL2, SOX9, ACAN, COL1) and production of extracellular matrix components. Histological assessment of in vitro and subcutaneously implanted in vivo constructs demonstrated that CM-expanded cells followed by TGF-β3 exposure resulted in highest cell proliferation, GAG accumulation, and collagen deposition. Furthermore, when implanted into meniscus defect model, CM treatment amplified the potential of TGF-β3 and induced complete regeneration. Conditioned medium derived from chondrocytes have been reported to effectively prime mesenchymal stem cells toward chondrogenic lineage. Type I collagen is the main component of meniscus extracellular matrix and hyaluronic acid is known to promote meniscus regeneration. In this manuscript, we investigated the effects of conditioned medium (CM) and transforming growth factor-β3 (TGF-β3) on tonsil-derived mesenchymal stem cells (T-MSCs) encapsulated in riboflavin-induced photocrosslinked collagen-hyaluronic acid (COL-RF-HA) hydrogel. We employed a novel source of conditioned medium, derived from meniscal fibrochondrocytes. Our in vitro and in vivo results collectively illustrate that CM-expanded cells followed by TGF-β3 exposure have the best potential for meniscus regeneration. This manuscript highlights a novel stem cell commitment strategy combined with biomaterials designs for meniscus regeneration. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Face resurfacing using a cervicothoracic skin flap prefabricated by lateral thigh fascial flap and tissue expander.

PubMed

Li, Qingfeng; Zan, Tao; Gu, Bin; Liu, Kai; Shen, Guoxiong; Xie, Yun; Weng, Rui

2009-01-01

Resurfacing of facial massive soft tissue defect is a formidable challenge because of the unique character of the region and the limitation of well-matched donor site. In this report, we introduce a technique for using the prefabricated cervicothoracic skin flap for facial resurfacing, in an attempt to meet the principle of flap selection in face reconstructive surgery for matching the color and texture, large dimension, and thinner thickness (MLT) of the recipient. Eleven patients with massive facial scars underwent resurfacing procedures with prefabricated cervicothoracic flaps. The vasculature of the lateral thigh fascial flap, including the descending branch of the lateral femoral circumflex vessels and the surrounding muscle fascia, was used as the vascular carrier, and the pedicles of the fascial flap were anastomosed to either the superior thyroid or facial vessels in flap prefabrication. A tissue expander was placed beneath the fascial flap to enlarge the size and reduce the thickness of the flap. The average size of the harvested fascia flap was 6.5 x 11.7 cm. After a mean interval of 21.5 weeks, the expanders were filled to a mean volume of 1,685 ml. The sizes of the prefabricated skin flaps ranged from 12 x 15 cm to 15 x 32 cm. The prefabricated skin flaps were then transferred to the recipient site as pedicled flaps for facial resurfacing. All facial soft tissue defects were successfully covered by the flaps. The donor sites were primarily closed and healed without complications. Although varied degrees of venous congestion were developed after flap transfers, the marginal necrosis only occurred in two cases. The results in follow-up showed most resurfaced faces restored natural contour and regained emotional expression. MLT is the principle for flap selection in resurfacing of the massive facial soft tissue defect. Our experience in this series of patients demonstrated that the prefabricated cervicothoracic skin flap could be a reliable alternative tool for resurfacing of massive facial soft tissue defects. (c) 2009 Wiley-Liss, Inc. Microsurgery, 2009.

77 FR 71825 - Notice of Temporary Restriction of Vehicle Use and Temporary Closure to Tree Cutting and Wood...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-04

... to Tree Cutting and Wood Harvesting on Public Land in Douglas County, NV AGENCY: Bureau of Land... a temporary closure to wood harvesting and/or tree cutting on public land within the Topaz Ranch... temporary restriction of cross-country vehicle travel and a temporary closure to tree cutting and wood...

Macrophage origin limits functional plasticity in helminth-bacterial co-infection

PubMed Central

Campbell, Sharon M.; Duncan, Sheelagh; Hewitson, James P.; Barr, Tom A.; Jackson-Jones, Lucy H.; Maizels, Rick M.

2017-01-01

Rapid reprogramming of the macrophage activation phenotype is considered important in the defense against consecutive infection with diverse infectious agents. However, in the setting of persistent, chronic infection the functional importance of macrophage-intrinsic adaptation to changing environments vs. recruitment of new macrophages remains unclear. Here we show that resident peritoneal macrophages expanded by infection with the nematode Heligmosomoides polygyrus bakeri altered their activation phenotype in response to infection with Salmonella enterica ser. Typhimurium in vitro and in vivo. The nematode-expanded resident F4/80high macrophages efficiently upregulated bacterial induced effector molecules (e.g. MHC-II, NOS2) similarly to newly recruited monocyte-derived macrophages. Nonetheless, recruitment of blood monocyte-derived macrophages to Salmonella infection occurred with equal magnitude in co-infected animals and caused displacement of the nematode-expanded, tissue resident-derived macrophages from the peritoneal cavity. Global gene expression analysis revealed that although nematode-expanded resident F4/80high macrophages made an anti-bacterial response, this was muted as compared to newly recruited F4/80low macrophages. However, the F4/80high macrophages adopted unique functional characteristics that included enhanced neutrophil-stimulating chemokine production. Thus, our data provide important evidence that plastic adaptation of MΦ activation does occur in vivo, but that cellular plasticity is outweighed by functional capabilities specific to the tissue origin of the cell. PMID:28334040

A New Great Game: US-China Competition in Guam and the CNMI

DTIC Science & Technology

2017-06-01

H-2B (temporary non- agricultural workers) visas is capped annually at a pre- 9 Report of the Visa...and the Economic Outlook 13 “H-2B Temporary Non- Agricultural Workers,” US Citizenship and Immigration...Services, November 2016, https://www.uscis.gov/working-united-states/temporary- workers/h-2b-temporary-non- agricultural -workers. 14 “H-2B Temporary

Patterning cellular compartments within TRACER cultures using sacrificial gelatin printing.

PubMed

Xu, Bin; Rodenhizer, Darren; Lakhani, Shakir; Zhang, Xiaoshu; Soleas, John P; Ailles, Laurie; McGuigan, Alison P

2016-09-15

In the past decade, it has been well recognised that the tumour microenvironment contains microenvironmental components such as hypoxia that significantly influence tumour cell behaviours such, invasiveness and therapy resistance, all of which provide new targets for studying cancer biology and developing anticancer therapeutics. In response, a large number of two-dimensional and three-dimensional (3D) in vitro tumour models have been developed to recapitulate different aspects of the tumour microenvironment and enable the study of related biological questions. While more complex models enable new biological insight, such models often involve time-consuming and complex fabrication or analysis processes, which limit their adoption by the broader cancer biology community. To address this, we recently reported the development of a new platform that enables easy assembly and analysis of 3D tumour cultures, the tissue roll for analysis of cellular environment response (TRACER). The TRACER platform enables recapitulation of many spatial aspects of the tumour microenvironment to ask a variety of questions, however its original design contains only one cell type. In contrast tumours in vivo often contain a neoplastic and stromal compartment. To expand the types of questions the TRACER system is useful for asking, here we present a strategy to pattern distinct cell type domains into TRACER layers using a custom-built gelatin-dispensing pen. The pen allows deposition of a temporary gelatin barrier into the TRACER scaffold to define domain boundaries between cell populations. The gelatin can be melted away after cell seeding to allow interaction of cell populations from adjacent domains. Our device offers a simple strategy to generate complex multi-cell type tumour cultures for analysis of fundamental biology and drug development applications.

Protective effect of melatonin on experimental spinal cord ischemia.

PubMed

Erten, S F; Kocak, A; Ozdemir, I; Aydemir, S; Colak, A; Reeder, B S

2003-10-01

Experimental animal model to assess ischemic spinal cord injury following occlusion of the thoraco-abdominal aorta. To measure whether melatonin administered to rabbits before and after occlusion exerts an effect on the repair of ischemia-reperfusion (IR) injury. Medical Biology Laboratory, Inonu University, Malatya, Turkey. Rabbits were divided into three IR treatment groups and one sham-operated (ShOp) control group. The three treatment groups had their infrarenal aorta temporarily occluded for 25 min, while the ShOp group had laparotomy without aortic occlusion. Melatonin was administered either 10 min before aortic occlusion or 10 min after the clamp was removed. Physiologic saline was administered to the control animals. After treatment, the animals were euthanized and lumbosacral spinal cord tissue was removed for the determination of relevant enzyme activities. Malondialdehyde levels, indicating the extent of lipid peroxidation, were found to be significantly increased in the nonmelatonin treated (IR) group when compared to the ShOp group. Melatonin, whether given to pre- or post occlusion groups, suppressed malondialdehyde levels below that of the ShOp group. Catalase (CAT) and glutathione peroxidase (GSH-Px) enzyme activities were increased in the IR group compared to the ShOp group. Melatonin given preocclusion resulted in a significant decrease in both CAT and GSH-Px enzyme levels. The superoxide dismutase (SOD) enzyme activity was decreased in the ischemia-reperfusion treatment group. However, the melatonin treatment increased SOD enzyme activity to levels approximating that of the ShOp group. To our knowledge, this is the first study that shows the effects of melatonin administered both pre- and postischemia on induced oxidative damage to injured spinal cords. Our data also expands on reports that melatonin administration may significantly reduce the incidence of spinal cord injury following temporary aortic occlusion.

Staged lengthening arthroplasty for pediatric osteosarcoma around the knee.

PubMed

Kong, Chang-Bae; Lee, Soo-Yong; Jeon, Dae-Geun

2010-06-01

Orthopaedic oncologists often must address leg-length discrepancy after resection of tumors in growing patients with osteosarcoma. There are various alternatives to address this problem. We describe a three-stage procedure: (1) temporary arthrodesis, (2) lengthening by Ilizarov apparatus, and (3) tumor prosthesis. We asked (1) to what extent are affected limbs actually lengthened; (2) how many of the patients who undergo a lengthening procedure eventually achieve joint arthroplasty; and (3) can the three-stage procedure give patients a functioning joint with equalization of limb length? We reviewed 56 patients (younger than 14 years) with osteosarcoma who had staged lengthening arthroplasty between 1991 and 2004. Thirty-five of the 56 patients (63%) underwent soft tissue lengthening, and of these 35, 28 (50% of the original group of 56) had implantation of a mobile joint. Three of the 28 prostheses were later removed owing to infection after arthroplasty. The overall average length gained was 7.8 cm (range, 4-14 cm), and 25 (71%) of the 35 patients had a mobile joint at final followup. The average Musculoskeletal Tumor Society functional score was 23.2 (range, 15-28) and limb-length discrepancy at final followup was 2.6 cm (range, 0-6.5 cm). Although most mobile joints had an acceptable ROM (average, 74.2 degrees ; range, 35 degrees -110 degrees ), extension lag was frequent. Our approach is one option for skeletally immature patients, especially in situations where an expandable prosthesis is not available. However, this technique requires multiple stages and would be inappropriate for patients who cannot accept prolonged functional deficit owing to a limited lifespan or other reasons. Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Immediate breast reconstruction with a myocutaneous latissimus dorsi flap and implant following skin-sparing salvage mastectomy after irradiation as part of breast-conserving therapy.

PubMed

van Huizum, Martine A; Hage, J Joris; Rutgers, Emiel J; Hoornweg, Marije J

2016-08-01

Local relapse after breast-conserving therapy including whole breast irradiation is typically treated by salvage mastectomy. Immediate reconstruction by pedicled transfer of a latissimus dorsi flap in combination with implantation of a definitive prosthesis or temporary tissue expander following skin sparing salvage mastectomy has been shown to be feasible. However, it has never been shown to be justifiable. The aim of the study was to compare the outcome of this procedure to the widely accepted secondary breast reconstruction by combined latissimus dorsi flap and implant after mastectomy and adjuvant radiotherapy. The surgical outcome of 93 immediate latissimus dorsi and implant reconstructions after skin-sparing salvage mastectomy performed from 2007 to 2011 after radiotherapy was compared to that of 83 secondary reconstructions with the latissimus dorsi and an implant. The follow-up duration was 3.5 years in both groups. Complications were categorized as minor (conservative treatment sufficed) or major (flap loss, mammary skin loss, implant loss, seroma or haematoma indicating repeat surgery). The salvage group scored significantly less on half of the patient-related and procedure-related risk factors. Nevertheless, we observed 27% of short-term major surgical complications and an ultimate success rate of 94% in the salvage group compared to those observed in our series of secondary reconstruction in post-radiation women (27% and 93%, respectively). Skin-sparing salvage mastectomy combined with immediate reconstruction by transfer of a latissimus dorsi flap with an implant is a justifiable reconstructive option for women with a recurrence after irradiation as part of breast-conserving therapy. Copyright © 2016 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Predictors of temporary epicardial pacing wires use after valve surgery

PubMed Central

2014-01-01

Background Although temporary cardiac pacing is infrequently needed, temporary epicardial pacing wires are routinely inserted after valve surgery. As they are associated with infrequent, but life threatening complications, and the decreased need for postoperative pacing in a group of low risk patients; this study aims to identify the predictors of temporary cardiac pacing after valve surgery. Methods A retrospective analysis of data collected prospectively on 400 consecutive valve surgery patients between May 2002 and December 2012 was performed. Patients were grouped according to avoidance or insertion of temporary pacing wires, and were further subdivided according to temporary cardiac pacing need. Multiple logistic regression was used to determine the predictors of temporary cardiac pacing. Results 170 (42.5%) patients did not have insertion of temporary pacing wires and none of them needed temporary pacing. 230 (57.5%) patients had insertion of temporary pacing wires and among these, only 55 (23.9%) required temporary pacing who were compared with the remaining 175 (76.1%) patients in the main analysis. The determinants of temporary cardiac pacing (adjusted odds ratios; 95% confidence interval) were as follows: increased age (1.1; 1.1, 1.3, p = 0.002), New York Heart Association class III- IV (5.6; 1.6, 20.2, p = 0.008) , pulmonary artery pressure ≥ 50 mmHg (22.0; 3.4, 142.7, p = 0.01), digoxin use (8.0; 1.3, 48.8, p = 0.024), multiple valve surgery (13.5; 1.5, 124.0, p = 0.021), aorta cross clamp time ≥ 60 minutes (7.8; 1.6, 37.2, p = 0.010), and valve annulus calcification (7.9; 2.0, 31.7, p = 0.003). Conclusion Although limited by sample size, the present results suggest that routine use of temporary epicardial pacing wires after valve surgery is only necessary for high risk patients. Preoperative identification and aggressive management of predictors of temporary cardiac pacing and the possible modulation of intraoperative techniques can decrease the need of temporary cardiac pacing. Prospective randomized controlled studies on a larger number of patients are necessary to draw solid conclusions regarding the selective use of temporary epicardial pacing wires in valve surgery. PMID:24521215

A case of motor neuropathy after cryolipolysis of the arm.

PubMed

Lee, Sang Jun; Kim, Young Jin; Park, Jae Beom; Suh, Dong Hye; Kwon, Do Young; Ryu, Hwa Jung

2016-11-01

Cryolipolysis treatment is a non-invasive option for localized fat reduction without damaging the surrounding tissue. Clinical studies about cryolipolysis show various side effects, including temporary erythema, bruising, and transient numbness. But, no reports are available on motor nerve malfunction after cryolipolysis. A 24-year-old female received cryolipolysis treatment on abdomen, both arms. After 10 days, patient complained of weakness and inability to lift heavy objects. Symptoms continued for 6 months, and fully recovered without treatment. Thus, we report a case of motor neuropathy after cryolipolysis, which is a rare complication of cryolipolysis.

Neutrophils: Between Host Defence, Immune Modulation, and Tissue Injury

PubMed Central

Kruger, Philipp; Saffarzadeh, Mona; Weber, Alexander N. R.; Rieber, Nikolaus; Radsak, Markus; von Bernuth, Horst; Benarafa, Charaf; Roos, Dirk; Skokowa, Julia; Hartl, Dominik

2015-01-01

Neutrophils, the most abundant human immune cells, are rapidly recruited to sites of infection, where they fulfill their life-saving antimicrobial functions. While traditionally regarded as short-lived phagocytes, recent findings on long-term survival, neutrophil extracellular trap (NET) formation, heterogeneity and plasticity, suppressive functions, and tissue injury have expanded our understanding of their diverse role in infection and inflammation. This review summarises our current understanding of neutrophils in host-pathogen interactions and disease involvement, illustrating the versatility and plasticity of the neutrophil, moving between host defence, immune modulation, and tissue damage. PMID:25764063

On the use of secondary capture-recapture samples to estimate temporary emigration and breeding proportions

USGS Publications Warehouse

Kendall, W.L.; Nichols, J.D.; North, P.M.; Nichols, J.D.

1995-01-01

The use of the Cormack- Jolly-Seber model under a standard sampling scheme of one sample per time period, when the Jolly-Seber assumption that all emigration is permanent does not hold, leads to the confounding of temporary emigration probabilities with capture probabilities. This biases the estimates of capture probability when temporary emigration is a completely random process, and both capture and survival probabilities when there is a temporary trap response in temporary emigration, or it is Markovian. The use of secondary capture samples over a shorter interval within each period, during which the population is assumed to be closed (Pollock's robust design), provides a second source of information on capture probabilities. This solves the confounding problem, and thus temporary emigration probabilities can be estimated. This process can be accomplished in an ad hoc fashion for completely random temporary emigration and to some extent in the temporary trap response case, but modelling the complete sampling process provides more flexibility and permits direct estimation of variances. For the case of Markovian temporary emigration, a full likelihood is required.

Feasibility and safety of placement of a newly designed, fully covered self-expandable metal stent for refractory benign pancreatic ductal strictures: a pilot study (with video).

PubMed

Park, Do Hyun; Kim, Myung-Hwan; Moon, Sung-Hoon; Lee, Sang Soo; Seo, Dong-Wan; Lee, Sung-Koo

2008-12-01

Painful chronic pancreatitis with main pancreatic ductal strictures is usually managed with endotherapy with a plastic stent. To date, the role of placement of metallic stents, especially uncovered ones in benign pancreatic ductal stricture, has been unsatisfactory as a result of stent dysfunction related to mucosal hyperplasia. We explored the feasibility and safety of temporary placement of a newly designed, fully covered self-expandable metal stent (FCSEMS) in painful chronic pancreatitis and refractory benign pancreatic ductal strictures. A prospective pilot and feasibility study. A tertiary academic center. Thirteen patients with chronic painful pancreatitis of alcoholic (8) or idiopathic (5) etiology. ERCP with temporary FCSEMS placement (2 months). Endoscopic removal of FCSEMSs was performed with a snare or rat-tooth forceps. End points were feasibility, safety, and morbidity. Successful FCSEMS placement was performed in all enrolled patients. After immediate placement of FCSEMS, 2 patients had mild acute pancreatitis related mainly to the stricture dilation procedure (Soehendra stent retriever or balloon dilation). Complications associated with stent placement included 5 migrations (39%, 1 proximal and 4 distal) and 2 incidents of cholestatic liver dysfunction associated with the compression of the bile duct orifice by expansion of FCSEMSs. In 1 patient with proximal migration, the stent was repositioned by an inflated retrieval balloon. Additional endoscopic biliary sphincterotomy with or without biliary stenting was performed in 2 patients with cholestatic liver dysfunction. There was no occurrence of pancreatic sepsis among any patients. FCSEMSs were removed from 9 of 9 patients without stent migration (100% [9/9] as per protocol, and 69% [9/13] as intention to treat, respectively). Improvement or resolution of the pancreatic ductal strictures was confirmed in all 13 patients on follow-up ERCP (2 months after stent placement), regardless of stent migration. Small patient populations without long-term follow-up. Two-month placement of FCSEMSs in patients with refractory benign pancreatic ductal strictures may be feasible and relatively safe. However, stent migration was not uncommon. A further investigation with ideal stent design may therefore be needed before recommending FCSEMSs as a therapeutic option for refractory benign pancreatic ductal strictures.

A non-randomized study in consecutive patients with postcholecystectomy refractory biliary leaks who were managed endoscopically with the use of multiple plastic stents or fully covered self-expandable metal stents (with videos).

PubMed

Canena, Jorge; Liberato, Manuel; Meireles, Liliane; Marques, Inês; Romão, Carlos; Coutinho, António Pereira; Neves, Beatriz Costa; Veiga, Pedro Mota

2015-07-01

Endoscopic management of postcholecystectomy biliary leaks is widely accepted as the treatment of choice. However, refractory biliary leaks after a combination of biliary sphincterotomy and the placement of a large-bore (10F) plastic stent can occur, and the optimal rescue endotherapy for this situation is unclear. To compare the clinical effectiveness of the use of a fully covered self-expandable metal stent (FCSEMS) with the placement of multiple plastic stents (MPS) for the treatment of postcholecystectomy refractory biliary leaks. Prospective study. Two tertiary-care referral academic centers and one general district hospital. Forty consecutive patients with refractory biliary leaks who underwent endoscopic management. Temporary placement of MPS (n = 20) or FCSEMSs (n = 20). Clinical outcomes of endotherapy as well as the technical success, adverse events, need for reinterventions, and prognostic factors for clinical success. Endotherapy was possible in all patients. After endotherapy, closure of the leak was accomplished in 13 patients (65%) who received MPS and in 20 patients (100%) who received FCSEMSs (P = .004). The Kaplan-Meier (log-rank) leak-free survival analysis showed a statistically significant difference between the 2 patient populations (χ(2) [1] = 8.30; P < .01) in favor of the FCSEMS group. Use of <3 plastic stents (P = .024), a plastic stent diameter <20F (P = .006), and a high-grade biliary leak (P = .015) were shown to be significant predictors of treatment failure with MPS. The 7 patients in whom placement of MPS failed were retreated with FCSEMSs, resulting in closure of the leaks in all cases. Non-randomized design. In our series, the results of the temporary placement of FCSEMSs for postcholecystectomy refractory biliary leaks were superior to those from the use of MPS. A randomized study is needed to confirm our results before further recommendations. Copyright © 2015 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

Self-Expandable Metal Stents and Trans-stent Light Delivery: Are Metal Stents and Photodynamic Therapy Compatible?

PubMed Central

Wang, Luo-Wei; Li, Li-Bo; Li, Zhao-Shen; Chen, Yang K; Hetzel, Fred W.; Huang, Zheng

2008-01-01

Background and Objectives: Obstructive non-small cell lung cancer and obstructive esophageal cancer are US FDA approved indications of photodynamic therapy (PDT). The usefulness of PDT for the treatment of cholangiocarcinoma is currently under clinical investigation. Endoscopic stenting for lumen restoration is a common palliative intervention for those indications. It is important to assess whether self-expandable metal stents are compatible with trans-stent PDT light delivery. Study Design/Materials and Methods: Direct effects of various components of metal biliary (n = 2), esophageal (n = 2), and bronchial (n = 1) stents on PDT light transmittance and distribution were examined using a point or linear light source (630 or 652 nm diode laser). Resected pig biliary duct and esophageal wall tissues were used to examine the feasibility of PDT light delivery through the fully expanded metal stents. Results: While using a point light source, the metal components (thread and joint) of the stent could cause a significant shadow effect. The liner material (polytetrafluoroethylene or polyurethane) could cause various degrees of light absorption. When the stent was covered with a thin layer of biliary duct and esophageal tissues containing all wall layers, the shadow effect could be mitigated due to tissue scattering. Conclusions: This study clearly demonstrates that it is feasible to combine stenting and PDT for the treatment of luminal lesions. PDT light dose should be adjusted to counteract the reduction of light transmittance caused by the metal and liner materials of stent. PMID:18951422

Control of rabbit dura mater optical properties with osmotical liquids

NASA Astrophysics Data System (ADS)

Yao, Lei; Cheng, Haiying; Luo, Qingming; Zhang, Wei; Zeng, Shaoqun; Tuchin, Valery V.

2002-04-01

An experimental study of controlling the optical properties of in vitro and in vivo rabbit dura mater with administration of osmotical agents, 40% glucose solution and glycerol, using video camera and spectrometer was presented. The preliminary results of experimental study of influence of osmotical liquids (glucose solutions, glycerol) on transmittance (in vitro) and reflectance (in vivo) spectra of rabbit dura mater were reported. The significant decreasing of the reflectance and increasing of the transmittance of dura mater under action of osmotical solutions were demonstrated. Experiments showed that administration of osmolytes to dura mater allowed for effective and temporary control of its optical characteristics, which made dura mater more transparent, increased the ability of light penetrating the tissue, and consequently improved the optical imaging depth. It is a significant study, which can improve penetration of optical imaging of cerebral function and acquire more information of the deep brain tissue.

Temporary Fixation Using a Long Femoral-tibial Nail to Treat a Displaced Medial Tibial Plateau Fracture in a 90-year-old Patient: A Case Report

PubMed Central

Batta, V; Sinha, S; Trompeter, A

2017-01-01

Introduction: Tibial plateau fractures are complex injuries in the elderly population. When traditional methods of fixation are not suitable, an alternative method needs to be chosen for a favorable outcome. We demonstrate a previously undescribed treatment for displaced tibial plateau fractures in the very elderly with poor soft-tissue integrity. Case Report: A 90-year-old woman suffered an open, Gustilo Grade IIIA, displaced fracture of the tibial plateau. An intramedullary knee arthrodesis, the femoral-tibial nail was used to temporarily stabilize her fracture. She was able to weight bear immediately postfixation. Conclusion: A long femoral-tibial nail allows favorable fracture and soft tissue healing, ease of nursing and immediate full weight-bearing. It shows good promise and should be considered as a management option when traditional methods are not applicable in select patients. PMID:29181350

Temporary Fixation Using a Long Femoral-tibial Nail to Treat a Displaced Medial Tibial Plateau Fracture in a 90-year-old Patient: A Case Report.

PubMed

Batta, V; Sinha, S; Trompeter, A

2017-01-01

Tibial plateau fractures are complex injuries in the elderly population. When traditional methods of fixation are not suitable, an alternative method needs to be chosen for a favorable outcome. We demonstrate a previously undescribed treatment for displaced tibial plateau fractures in the very elderly with poor soft-tissue integrity. A 90-year-old woman suffered an open, Gustilo Grade IIIA, displaced fracture of the tibial plateau. An intramedullary knee arthrodesis, the femoral-tibial nail was used to temporarily stabilize her fracture. She was able to weight bear immediately postfixation. A long femoral-tibial nail allows favorable fracture and soft tissue healing, ease of nursing and immediate full weight-bearing. It shows good promise and should be considered as a management option when traditional methods are not applicable in select patients.

76 FR 34080 - Agency Information Collection Activities; Proposed Collection; Comment Request; Temporary...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-10

...] Agency Information Collection Activities; Proposed Collection; Comment Request; Temporary Marketing... existing FDA regulations governing temporary marketing permit applications. DATES: Submit either electronic... appropriate, and other forms of information technology. Temporary Marketing Permit Applications--21 CFR 130.17...

Safety evaluation of the temporary consolidant based on a zebrafish embryo model.

PubMed

Zhang, Lu; Zhang, Xiao Yan; Hu, Yulan; Zhang, Bing Jian

2018-05-07

Temporary consolidants, such as cyclododecane, menthol, coumarin, and ethyl maltol, are proved to be effective for urgent conservation in archaeological field. However, the safety of these temporary consolidants is still unknown although they are always heavily used in archaeological field. Thus reports on the toxicity of these temporary consolidants are limited. Here, a zebrafish model was used for safety evaluation of these four temporary consolidants. In the present study, four temporary consolidants, including cyclododecane, menthol, coumarin, and ethyl maltol, at different concentrations were incubated with zebrafish embryos, and their biological toxic effects were firstly evaluated. It was shown that embryo exposure to temporary consolidants resulted in an increased mortality and malformation rate, and a decreased hatching rate. The order of embryo toxicity of the four types of temporary consolidants tested was menthol > coumarin > ethyl maltol > cyclododecane. Although the embryo toxicity of cyclododecane was minimal, some studies have indicated that this temporary consolidant could be bioaccumulated. The results also suggested that the zebrafish embryos can serve as a reliable model for the evaluation of embryo toxicity of temporary consolidants, as this model could offer the possibility to perform the rapid, medium throughput, cost-effective analyses. Copyright © 2018 Elsevier Ltd. All rights reserved.

NaCl-Induced Alterations in Both Cell Structure and Tissue-Specific Plasma Membrane H+ -ATPase Gene Expression.

PubMed Central

Niu, X.; Damsz, B.; Kononowicz, A. K.; Bressan, R. A.; Hasegawa, P. M.

1996-01-01

NaCl-induced plasma membrane H+-ATPase gene expression, which occurs in roots and fully expanded leaves of the halophyte Atriplex nummularia L. (X. Niu, M.L. Narasimhan, R.A. Salzman, R.A. Bressan, P.M. Hasegawa [1993] Plant Physiol 103: 713-718), has been differentially localized to specific tissues using in situ RNA hybridization techniques. Twenty-four-hour exposure of plants to 400 mM NaCl resulted in substantial accumulation of H+ pump message in the epidermis of the root tip and the endodermis of the root elongation/differentiation zone. In expanded leaves, NaCl induction of plasma membrane H+-ATPase message accumulation was localized to bundle-sheath cells. Ultrastructural analyses indicated that significant cytological adaptations in root cells included plasmolysis that is accompanied by plasma membrane invaginations, formation of Hechtian strands and vesiculation, and vacuolation. These results identify specific tissues that are involved in the regulation of Na+ and Cl- uptake into different organs of the halophyte A. nummularia and provide evidence of the intercellular and interorgan coordination that occurs in the mediation of NaCl adaptation. PMID:12226321

NaCl-Induced Alterations in Both Cell Structure and Tissue-Specific Plasma Membrane H+ -ATPase Gene Expression.

PubMed

Niu, X.; Damsz, B.; Kononowicz, A. K.; Bressan, R. A.; Hasegawa, P. M.

1996-07-01

NaCl-induced plasma membrane H+-ATPase gene expression, which occurs in roots and fully expanded leaves of the halophyte Atriplex nummularia L. (X. Niu, M.L. Narasimhan, R.A. Salzman, R.A. Bressan, P.M. Hasegawa [1993] Plant Physiol 103: 713-718), has been differentially localized to specific tissues using in situ RNA hybridization techniques. Twenty-four-hour exposure of plants to 400 mM NaCl resulted in substantial accumulation of H+ pump message in the epidermis of the root tip and the endodermis of the root elongation/differentiation zone. In expanded leaves, NaCl induction of plasma membrane H+-ATPase message accumulation was localized to bundle-sheath cells. Ultrastructural analyses indicated that significant cytological adaptations in root cells included plasmolysis that is accompanied by plasma membrane invaginations, formation of Hechtian strands and vesiculation, and vacuolation. These results identify specific tissues that are involved in the regulation of Na+ and Cl- uptake into different organs of the halophyte A. nummularia and provide evidence of the intercellular and interorgan coordination that occurs in the mediation of NaCl adaptation.

Cellular control of connective tissue matrix tension.

PubMed

Langevin, Helene M; Nedergaard, Maiken; Howe, Alan K

2013-08-01

The biomechanical behavior of connective tissue in response to stretching is generally attributed to the molecular composition and organization of its extracellular matrix. It also is becoming apparent that fibroblasts play an active role in regulating connective tissue tension. In response to static stretching of the tissue, fibroblasts expand within minutes by actively remodeling their cytoskeleton. This dynamic change in fibroblast shape contributes to the drop in tissue tension that occurs during viscoelastic relaxation. We propose that this response of fibroblasts plays a role in regulating extracellular fluid flow into the tissue, and protects against swelling when the matrix is stretched. This article reviews the evidence supporting possible mechanisms underlying this response including autocrine purinergic signaling. We also discuss fibroblast regulation of connective tissue tension with respect to lymphatic flow, immune function, and cancer. Copyright © 2013 Wiley Periodicals, Inc.

Ultrasound in Radiology: from Anatomic, Functional, Molecular Imaging to Drug Delivery and Image-Guided Therapy

PubMed Central

Klibanov, Alexander L.; Hossack, John A.

2015-01-01

During the past decade, ultrasound has expanded medical imaging well beyond the “traditional” radiology setting - a combination of portability, low cost and ease of use makes ultrasound imaging an indispensable tool for radiologists as well as for other medical professionals who need to obtain imaging diagnosis or guide a therapeutic intervention quickly and efficiently. Ultrasound combines excellent ability for deep penetration into soft tissues with very good spatial resolution, with only a few exceptions (i.e. those involving overlying bone or gas). Real-time imaging (up to hundreds and thousands frames per second) enables guidance of therapeutic procedures and biopsies; characterization of the mechanical properties of the tissues greatly aids with the accuracy of the procedures. The ability of ultrasound to deposit energy locally brings about the potential for localized intervention encompassing: tissue ablation, enhancing penetration through the natural barriers to drug delivery in the body and triggering drug release from carrier micro- and nanoparticles. The use of microbubble contrast agents brings the ability to monitor and quantify tissue perfusion, and microbubble targeting with ligand-decorated microbubbles brings the ability to obtain molecular biomarker information, i.e., ultrasound molecular imaging. Overall, ultrasound has become the most widely used imaging modality in modern medicine; it will continue to grow and expand. PMID:26200224

Estimating temporary emigration and breeding proportions using capture-recapture data with Pollock's robust design

USGS Publications Warehouse

Kendall, W.L.; Nichols, J.D.; Hines, J.E.

1997-01-01

Statistical inference for capture-recapture studies of open animal populations typically relies on the assumption that all emigration from the studied population is permanent. However, there are many instances in which this assumption is unlikely to be met. We define two general models for the process of temporary emigration, completely random and Markovian. We then consider effects of these two types of temporary emigration on Jolly-Seber (Seber 1982) estimators and on estimators arising from the full-likelihood approach of Kendall et al. (1995) to robust design data. Capture-recapture data arising from Pollock's (1982) robust design provide the basis for obtaining unbiased estimates of demographic parameters in the presence of temporary emigration and for estimating the probability of temporary emigration. We present a likelihood-based approach to dealing with temporary emigration that permits estimation under different models of temporary emigration and yields tests for completely random and Markovian emigration. In addition, we use the relationship between capture probability estimates based on closed and open models under completely random temporary emigration to derive three ad hoc estimators for the probability of temporary emigration, two of which should be especially useful in situations where capture probabilities are heterogeneous among individual animals. Ad hoc and full-likelihood estimators are illustrated for small mammal capture-recapture data sets. We believe that these models and estimators will be useful for testing hypotheses about the process of temporary emigration, for estimating demographic parameters in the presence of temporary emigration, and for estimating probabilities of temporary emigration. These latter estimates are frequently of ecological interest as indicators of animal movement and, in some sampling situations, as direct estimates of breeding probabilities and proportions.

Human liver infiltrating γδ T cells are composed of clonally expanded circulating and tissue-resident populations.

PubMed

Hunter, Stuart; Willcox, Carrie R; Davey, Martin S; Kasatskaya, Sofya A; Jeffery, Hannah C; Chudakov, Dmitriy M; Oo, Ye H; Willcox, Benjamin E

2018-05-18

γδ T-cells comprise a substantial proportion of tissue-associated lymphocytes. However, our current understanding of human γδ T-cells is primarily based on peripheral blood subsets, while the immunobiology of tissue-associated subsets remains largely unclear. To address this, we characterised the TCR diversity, immunophenotype and function of human liver infiltrating γδ T-cells, focussing on the predominant tissue-associated Vδ2 neg γδ subset, which is implicated in liver immunopathology. Intrahepatic Vδ2 neg γδ T-cells were highly clonally focussed, with single expanded clonotypes featuring complex, private TCR rearrangements frequently dominating the compartment. Such T-cells were predominantly CD27 lo/neg effector lymphocytes, whereas naïve CD27 hi , TCR diverse populations present in matched blood were generally absent in the liver. Furthermore, while a CD45RA hi Vδ2 neg γδ effector subset present in both liver and peripheral blood contained overlapping TCR clonotypes, the liver Vδ2 neg γδ T-cell pool also included a phenotypically distinct CD45RA lo effector compartment that was enriched for expression of the tissue tropism marker CD69, the hepatic homing chemokine receptors CXCR3 and CXCR6, and liver-restricted TCR clonotypes, suggestive of intrahepatic tissue residency. Liver infiltrating Vδ2 neg γδ cells were capable of polyfunctional cytokine secretion, and unlike peripheral blood subsets, were responsive to both TCR and innate stimuli. These findings suggest the ability of Vδ2 neg γδ T-cells to undergo clonotypic expansion and differentiation is crucial in permitting access to solid tissues such as the liver, and can result in functionally distinct peripheral and liver-resident memory γδ T-cell subsets. They highlight the inherent functional plasticity within the Vδ2 neg γδ T-cell compartment, and may inform design of cellular therapies involving intrahepatic trafficking of γδ T-cells to suppress liver inflammation or combat liver cancer. γδ T cells are frequently enriched in many solid tissues, however the immunobiology of such tissue-associated subsets in humans has remained unclear. We show that intrahepatic γδ T cells are enriched for clonally expanded effector T cells, whereas naïve γδ T cells are largely excluded; moreover, whereas a distinct proportion of circulating T cell clonotypes was present in both the liver tissue and peripheral blood, a functionally and clonotypically distinct population of liver-resident γδ T cells was also evident. Our findings suggest that factors triggering γδ T cell clonal selection and differentiation, such as infection, can drive enrichment of γδ T cells into liver tissue, allowing the development of functionally distinct tissue-restricted memory populations specialised in local hepatic immunosurveillance. Copyright © 2018 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Influence of temporary cement contamination on the surface free energy and dentine bond strength of self-adhesive cements.

PubMed

Takimoto, Masayuki; Ishii, Ryo; Iino, Masayoshi; Shimizu, Yusuke; Tsujimoto, Akimasa; Takamizawa, Toshiki; Ando, Susumu; Miyazaki, Masashi

2012-02-01

The surface free energy and dentine bond strength of self-adhesive cements were examined after the removal of temporary cements. The labial dentine surfaces of bovine mandibular incisors were wet ground with #600-grit SiC paper. Acrylic resin blocks were luted to the prepared dentine surfaces using HY Bond Temporary Cement Hard (HY), IP Temp Cement (IP), Fuji TEMP (FT) or Freegenol Temporary Cement (TC), and stored for 1 week. After removal of the temporary cements with an ultrasonic tip, the contact angle values of five specimens per test group were determined for the three test liquids, and the surface-energy parameters of the dentine surfaces were calculated. The dentine bond strengths of the self-adhesive cements were measured after removal of the temporary cements in a shear mode at a crosshead speed of 1.0mm/min. The data were subjected to one-way analysis of variance (ANOVA) followed by Tukey's HSD test. For all surfaces, the value of the estimated surface tension component γ(S)(d) (dispersion) was relatively constant at 41.7-43.3 mJm(-2). After removal of the temporary cements, the value of the γ(S)(h) (hydrogen-bonding) component decreased, particularly with FT and TC. The dentine bond strength of the self-adhesive cements was significantly higher for those without temporary cement contamination (8.2-10.6 MPa) than for those with temporary cement contamination (4.3-7.1 MPa). The γ(S) values decreased due to the decrease of γ(S)(h) values for the temporary cement-contaminated dentine. Contamination with temporary cements led to lower dentine bond strength. The presence of temporary cement interferes with the bonding performance of self-adhesive cements to dentine. Care should be taken in the methods of removal of temporary cement when using self-adhesive cements. Copyright © 2011 Elsevier Ltd. All rights reserved.

Temporary stream and wetland crossing options for forest management.

Treesearch

Charles R. Blinn; Rick Dahlman; Lola Hislop; Michael A. Thompson

1998-01-01

Discusses temporary options for crossing streams and wetland soils with forest harvesting and transportation equipment. Reviews the available literature on the environmental effects of temporary crossings. Provides an overview of regulations pertaining to temporary crossings for several jurisdictions in the Great Lakes Region.

Temporary stream and wetland crossing options for forest management

Treesearch

Charles R. Blinn; Rick Dahlman; Lola Hislop; Michael A. Thompson

1998-01-01

Discusses temporary options for crossing streams and wetland soils with forest harvesting and transportation equipment. Reviews the available literature on the environmental effects of temporary crossings. Provides an overview of regulations pertaining to temporary crossings for several jurisdictions in the Great Lakes Region.

19 CFR 210.52 - Motions for temporary relief.

Code of Federal Regulations, 2010 CFR

2010-04-01

....52 Customs Duties UNITED STATES INTERNATIONAL TRADE COMMISSION INVESTIGATIONS OF UNFAIR PRACTICES IN IMPORT TRADE ADJUDICATION AND ENFORCEMENT Temporary Relief § 210.52 Motions for temporary relief... issuance of temporary relief, the Commission will be guided by practice under Rule 65 of the Federal Rules...

21 CFR 1210.24 - Temporary permits.

Code of Federal Regulations, 2011 CFR

2011-04-01

... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... FEDERAL IMPORT MILK ACT Permit Control § 1210.24 Temporary permits. A temporary permit will be granted... inspections required by the applicable provisions of section 2 of the Federal Import Milk Act. Temporary...

21 CFR 1210.24 - Temporary permits.

Code of Federal Regulations, 2010 CFR

2010-04-01

... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... FEDERAL IMPORT MILK ACT Permit Control § 1210.24 Temporary permits. A temporary permit will be granted... inspections required by the applicable provisions of section 2 of the Federal Import Milk Act. Temporary...

14 CFR 47.16 - Temporary registration numbers.

Code of Federal Regulations, 2010 CFR

2010-01-01

... AIRCRAFT REGISTRATION General § 47.16 Temporary registration numbers. (a) Temporary registration numbers... Registration Certificates for temporary display on aircraft during flight allowed under Subpart C of this part. (b) The holder of a Dealer's Aircraft Registration Certificate may apply to the FAA Aircraft Registry...

14 CFR 47.16 - Temporary registration numbers.

Code of Federal Regulations, 2012 CFR

2012-01-01

... AIRCRAFT REGISTRATION General § 47.16 Temporary registration numbers. (a) Temporary registration numbers... Registration Certificates, AC Form 8050-6, for temporary display on aircraft during flight allowed under Subpart C of this part. (b) The holder of a Dealer's Aircraft Registration Certificate may apply to the...

14 CFR 47.16 - Temporary registration numbers.

Code of Federal Regulations, 2011 CFR

2011-01-01

... AIRCRAFT REGISTRATION General § 47.16 Temporary registration numbers. (a) Temporary registration numbers... Registration Certificates, AC Form 8050-6, for temporary display on aircraft during flight allowed under Subpart C of this part. (b) The holder of a Dealer's Aircraft Registration Certificate may apply to the...

14 CFR 47.16 - Temporary registration numbers.

Code of Federal Regulations, 2013 CFR

2013-01-01

... AIRCRAFT REGISTRATION General § 47.16 Temporary registration numbers. (a) Temporary registration numbers... Registration Certificates, AC Form 8050-6, for temporary display on aircraft during flight allowed under Subpart C of this part. (b) The holder of a Dealer's Aircraft Registration Certificate may apply to the...

14 CFR 47.16 - Temporary registration numbers.

Code of Federal Regulations, 2014 CFR

2014-01-01

... AIRCRAFT REGISTRATION General § 47.16 Temporary registration numbers. (a) Temporary registration numbers... Registration Certificates, AC Form 8050-6, for temporary display on aircraft during flight allowed under Subpart C of this part. (b) The holder of a Dealer's Aircraft Registration Certificate may apply to the...

Diaphragmatic hernia repair - series (image)

MedlinePlus

... The lung tissue on the affected side is compressed, fails to grow normally, and is unable to expand after birth. As the child begins to breathe, cry, and swallow, air enters the intestines that are protruding into the ...

76 FR 17135 - Clarifying Edits to Existing Special Controls Guidance Documents; Availability

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-28

... Virus, 29. Endotoxin Assay, 30. Dental Sonography and Jaw Tracking Devices, 31. Human Dura Mater... for the Topical Approximation of Skin, 78. Bone Sonometers, 79. Tissue Expander, 80. Cord Blood...

Preservation of EDTA-expanded grid-mounted chromosomes and nuclei for electron microscopy using a specially designed freeze-dryer.

PubMed

Woods, P S; Ledbetter, M C; Tempel, N

1991-06-01

We describe methods for freezing and drying EDTA-expanded, fixed metaphase chromosomes and nuclei, attached to grids as whole-mounts, for transmission electron microscopy. These methods use a special apparatus that is simple to construct. While separate freezers and dryers are commercially available, one for freezing blocks of tissue by slamming them against a cold metal surface, and the other for vacuum drying the frozen tissue, our apparatus is designed for gentler, cryogenic liquid plunge freezing and drying, sequentially, in the same apparatus, thus avoiding any compression or damage to the specimen. Use of a cryoprotectant is not essential; however, good results are obtained more often when 20% ethanol is used. Freezing is accomplished by rapid propulsion of the grid, with specimens attached, into slushy N2 (-210 degrees C) within the drying chamber; drying is automatic, by either sublimation under vacuum or by solvent substitution using absolute ethanol followed by acetone, which, in turn, is removed with a critical-point dryer. The apparatus offers a means of drying chromosomes and nuclei in an expanded state, and avoids the shrinkage of these structures that occurs during stepwise passage through increasing concentrations of ethanol or acetone.

49 CFR 193.2019 - Mobile and temporary LNG facilities.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false Mobile and temporary LNG facilities. 193.2019... LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS General § 193.2019 Mobile and temporary LNG facilities. (a) Mobile and temporary LNG facilities for peakshaving application, for service maintenance...

40 CFR 264.553 - Temporary Units (TU).

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Temporary Units (TU). 264.553 Section 264.553 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED... Provisions for Cleanup § 264.553 Temporary Units (TU). (a) For temporary tanks and container storage areas...

40 CFR 264.553 - Temporary Units (TU).

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Temporary Units (TU). 264.553 Section 264.553 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED... Provisions for Cleanup § 264.553 Temporary Units (TU). (a) For temporary tanks and container storage areas...

20 CFR 655.209 - Invalidation of temporary labor certifications.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Invalidation of temporary labor... LABOR TEMPORARY EMPLOYMENT OF FOREIGN WORKERS IN THE UNITED STATES Labor Certification Process for Logging Employment and Non-H-2A Agricultural Employment § 655.209 Invalidation of temporary labor...

33 CFR 72.01-30 - Temporary deficiencies.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Temporary deficiencies. 72.01-30 Section 72.01-30 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION MARINE INFORMATION Notices to Mariners § 72.01-30 Temporary deficiencies. Temporary deficiencies...

33 CFR 72.01-30 - Temporary deficiencies.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Temporary deficiencies. 72.01-30 Section 72.01-30 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION MARINE INFORMATION Notices to Mariners § 72.01-30 Temporary deficiencies. Temporary deficiencies...

77 FR 63835 - Office of the Chief Information Officer; Submission for OMB Review; Temporary Contractor...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-17

... of the Chief Information Officer; Submission for OMB Review; Temporary Contractor Information... information collection requirement regarding temporary contractor information worksheet. A notice was... for temporary contractors as a result of the American Recovery and Reinvestment Act of 2009 (Public...

Immunosuppression and temporary skin transplantation in the treatment of massive third degree burns.

PubMed Central

Burke, J F; Quinby, W C; Bondoc, C C; Cosimi, A B; Russell, P S; Szyfelbein, S K

1975-01-01

A method of burn treatment (immunosuppression and temporary skin transplantation) for patients suffering from massive third degree burns is evaluated. The method is based on the prompt excision of all dead tissue (burn eschar) and immediate closure of the wound by skin grafts. Total wound closure is achieved before bacterial infection or organ failure takes place by carrying out all initial excision and grafting procedures within the first ten days post burn and supplementing the limited amount of autograft with allograft. Continuous wound closure is maintained for up to 50 days through immunosuppression. Both azathioprine and ATG have been used but ATG is preferred. During the period of immunosuppression, allograft is stepwise excised and replaced with autograft donor sites regenerate for recropping. Bacterial complications are minimized by housing the patient in the protected environment of the Bacteria Controlled Nursing Unit. Intensive protein and calorie alimentation are provided, and 0.5% aqueous AgNO3 dressings are used. A swinging febrile illness has been associated with large areas of allograft rejection. Eleven children have been treated and seven have been returned to normal, productive schooling. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. PMID:809014

Multiscale Inorganic Hierarchically Materials: Towards an Improved Orthopaedic Regenerative Medicine.

PubMed

Ruso, Juan M; Sartuqui, Javier; Messina, Paula V

2015-01-01

Bone is a biologically and structurally sophisticated multifunctional tissue. It dynamically responds to biochemical, mechanical and electrical clues by remodelling itself and accordingly the maximum strength and toughness are along the lines of the greatest applied stress. The challenge is to develop an orthopaedic biomaterial that imitates the micro- and nano-structural elements and compositions of bone to locally match the properties of the host tissue resulting in a biologically fixed implant. Looking for the ideal implant, the convergence of life and materials sciences occurs. Researchers in many different fields apply their expertise to improve implantable devices and regenerative medicine. Materials of all kinds, but especially hierarchical nano-materials, are being exploited. The application of nano-materials with hierarchical design to calcified tissue reconstructive medicine involve intricate systems including scaffolds with multifaceted shapes that provides temporary mechanical function; materials with nano-topography modifications that guarantee their integration to tissues and that possesses functionalized surfaces to transport biologic factors to stimulate tissue growth in a controlled, safe, and rapid manner. Furthermore materials that should degrade on a timeline coordinated to the time that takes the tissues regrow, are prepared. These implantable devices are multifunctional and for its construction they involve the use of precise strategically techniques together with specific material manufacturing processes that can be integrated to achieve in the design, the required multifunctionality. For such reasons, even though the idea of displacement from synthetic implants and tissue grafts to regenerative-medicine-based tissue reconstruction has been guaranteed for well over a decade, the reality has yet to emerge. In this paper, we examine the recent approaches to create enhanced bioactive materials. Their design and manufacturing procedures as well as the experiments to integrate them into engineer hierarchical inorganic materials for their practical application in calcified tissue reparation are evaluated.

A Longitudinal Assessment of Outcomes and Healthcare Resource Utilization After Immediate Breast Reconstruction-Comparing Implant- and Autologous-based Breast Reconstruction.

PubMed

Fischer, John P; Fox, Justin P; Nelson, Jonas A; Kovach, Stephen J; Serletti, Joseph M

2015-10-01

Immediate breast reconstruction (IBR) after mastectomy for cancer has increased in recent years, yet long-term, modality-specific comparative data are lacking. We performed this study to compare short- and long-term outcomes after expander, autologous (AT), and direct-to-implant (DI) breast reconstruction. Using four state-level inpatient and ambulatory surgery databases, we conducted a retrospective cohort study of adult women who underwent mastectomy with immediate breast reconstruction from 2008 to 2009. Our primary outcomes were complications within 90 days of surgery, rate of secondary breast surgery within 3 years, and cumulative healthcare charges. The final cohort included 15,154 women who underwent mastectomy with tissue expander (TE: 70.5%), autologous (AT: 18.1%), or direct to implant (DI: 11.3%) reconstruction. Ninety-day complications were lowest after expander and highest after AT breast reconstruction (TE = 6.5% [reference] vs AT = 13.1% [2.09, 1.82-2.41] vs DI = 6.6% [1.03, 0.84-1.27], P < 0.001). However, adjusted rates of secondary breast procedures were most frequent after expander (2021/1000 discharges) and least frequent after AT (949.0/1000 discharges) reconstruction (P < 0.001). Specifically, unplanned revisions were highest among the tissue expander cohort (TE = 59.2% vs AT = 34.4% vs DI = 45.9%, P < 0.001). The cumulative, adjusted healthcare charges for secondary breast procedures differed slightly across groups (TE = $63,806 vs AT = $66,882 vs DI = $64,145, P < 0.001). Complications and secondary breast procedures, including unplanned revisions, after breast reconstruction are common and vary by reconstructive modality. The frequency of these secondary procedures adds substantial healthcare charges to the care of the breast reconstruction patient.

30 CFR 75.603 - Temporary splice of trailing cable.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Temporary splice of trailing cable. 75.603... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.603 Temporary splice of trailing cable. [Statutory Provision] One temporary splice may be made in any trailing cable...

20 CFR 655.172 - Withdrawal of job order and application for temporary employment certification.

Code of Federal Regulations, 2011 CFR

2011-04-01

... temporary employment certification. 655.172 Section 655.172 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR TEMPORARY EMPLOYMENT OF FOREIGN WORKERS IN THE UNITED STATES Labor Certification Process for Temporary Agricultural Employment in the United States (H-2A Workers) Post...

42 CFR 488.835 - Temporary management.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 42 Public Health 5 2013-10-01 2013-10-01 false Temporary management. 488.835 Section 488.835... Sanctions for Home Health Agencies With Deficiencies § 488.835 Temporary management. (a) Application. (1) CMS may impose temporary management of an HHA if it determines that an HHA has a condition-level...

42 CFR 488.835 - Temporary management.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 42 Public Health 5 2014-10-01 2014-10-01 false Temporary management. 488.835 Section 488.835... Sanctions for Home Health Agencies With Deficiencies § 488.835 Temporary management. (a) Application. (1) CMS may impose temporary management of an HHA if it determines that an HHA has a condition-level...

22 CFR 123.5 - Temporary export licenses.

Code of Federal Regulations, 2014 CFR

2014-04-01

... AND TEMPORARY IMPORT OF DEFENSE ARTICLES § 123.5 Temporary export licenses. (a) The Directorate of Defense Trade Controls may issue a license for the temporary export of unclassified defense articles (DSP... Defense Trade Controls if the article is to remain outside the United States beyond the period for which...

30 CFR 47.44 - Temporary, portable containers.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Temporary, portable containers. 47.44 Section... TRAINING HAZARD COMMUNICATION (HazCom) Container Labels and Other Forms of Warning § 47.44 Temporary, portable containers. (a) The operator does not have to label a temporary, portable container if he or she...

46 CFR 112.15-1 - Temporary emergency loads.

Code of Federal Regulations, 2014 CFR

2014-10-01

... AND POWER SYSTEMS Emergency Loads § 112.15-1 Temporary emergency loads. On vessels required by § 112.05-5(a) to have a temporary emergency power source, the following emergency lighting and power loads must be arranged so that they can be energized from the temporary emergency power source: (a...

46 CFR 112.15-1 - Temporary emergency loads.

Code of Federal Regulations, 2012 CFR

2012-10-01

... AND POWER SYSTEMS Emergency Loads § 112.15-1 Temporary emergency loads. On vessels required by § 112.05-5(a) to have a temporary emergency power source, the following emergency lighting and power loads must be arranged so that they can be energized from the temporary emergency power source: (a...

46 CFR 112.15-1 - Temporary emergency loads.

Code of Federal Regulations, 2013 CFR

2013-10-01

... AND POWER SYSTEMS Emergency Loads § 112.15-1 Temporary emergency loads. On vessels required by § 112.05-5(a) to have a temporary emergency power source, the following emergency lighting and power loads must be arranged so that they can be energized from the temporary emergency power source: (a...

Temporary Employment and Perceived Employability: Mediation by Impression Management

ERIC Educational Resources Information Center

De Cuyper, Nele; De Witte, Hans

2010-01-01

Perceived employability (PE) has been advanced as the upcoming resource for career development, particularly for temporary workers. The question is how temporary workers become employable. Our hypothesis is that temporary workers more than permanent workers use impression management to become employable, both on the internal and the external labor…

19 CFR 146.35 - Temporary deposit in a zone; incomplete documentation.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 19 Customs Duties 2 2010-04-01 2010-04-01 false Temporary deposit in a zone; incomplete... SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) FOREIGN TRADE ZONES Admission of Merchandise to a Zone § 146.35 Temporary deposit in a zone; incomplete documentation. (a) General. Temporary deposit of...

19 CFR 146.35 - Temporary deposit in a zone; incomplete documentation.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 19 Customs Duties 2 2013-04-01 2013-04-01 false Temporary deposit in a zone; incomplete... SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) FOREIGN TRADE ZONES Admission of Merchandise to a Zone § 146.35 Temporary deposit in a zone; incomplete documentation. (a) General. Temporary deposit of...

19 CFR 146.35 - Temporary deposit in a zone; incomplete documentation.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 19 Customs Duties 2 2012-04-01 2012-04-01 false Temporary deposit in a zone; incomplete... SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) FOREIGN TRADE ZONES Admission of Merchandise to a Zone § 146.35 Temporary deposit in a zone; incomplete documentation. (a) General. Temporary deposit of...

19 CFR 146.35 - Temporary deposit in a zone; incomplete documentation.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 19 Customs Duties 2 2014-04-01 2014-04-01 false Temporary deposit in a zone; incomplete... SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) FOREIGN TRADE ZONES Admission of Merchandise to a Zone § 146.35 Temporary deposit in a zone; incomplete documentation. (a) General. Temporary deposit of...

19 CFR 146.35 - Temporary deposit in a zone; incomplete documentation.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 19 Customs Duties 2 2011-04-01 2011-04-01 false Temporary deposit in a zone; incomplete... SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) FOREIGN TRADE ZONES Admission of Merchandise to a Zone § 146.35 Temporary deposit in a zone; incomplete documentation. (a) General. Temporary deposit of...

36 CFR 13.182 - Temporary facilities.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Temporary facilities. 13.182... NATIONAL PARK SYSTEM UNITS IN ALASKA Cabins Use of Temporary Facilities Related to Taking Fish and Wildlife § 13.182 Temporary facilities. In a national preserve where the taking of fish and wildlife is...

22 CFR 120.18 - Temporary import.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Temporary import. 120.18 Section 120.18 Foreign Relations DEPARTMENT OF STATE INTERNATIONAL TRAFFIC IN ARMS REGULATIONS PURPOSE AND DEFINITIONS § 120.18 Temporary import. Temporary import means bringing into the United States from a foreign country any defense...

22 CFR 120.18 - Temporary import.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Temporary import. 120.18 Section 120.18 Foreign Relations DEPARTMENT OF STATE INTERNATIONAL TRAFFIC IN ARMS REGULATIONS PURPOSE AND DEFINITIONS § 120.18 Temporary import. Temporary import means bringing into the United States from a foreign country any defense...

22 CFR 120.18 - Temporary import.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Temporary import. 120.18 Section 120.18 Foreign Relations DEPARTMENT OF STATE INTERNATIONAL TRAFFIC IN ARMS REGULATIONS PURPOSE AND DEFINITIONS § 120.18 Temporary import. Temporary import means bringing into the United States from a foreign country any defense...

22 CFR 120.18 - Temporary import.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Temporary import. 120.18 Section 120.18 Foreign Relations DEPARTMENT OF STATE INTERNATIONAL TRAFFIC IN ARMS REGULATIONS PURPOSE AND DEFINITIONS § 120.18 Temporary import. Temporary import means bringing into the United States from a foreign country any defense...

22 CFR 120.18 - Temporary import.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Temporary import. 120.18 Section 120.18 Foreign Relations DEPARTMENT OF STATE INTERNATIONAL TRAFFIC IN ARMS REGULATIONS PURPOSE AND DEFINITIONS § 120.18 Temporary import. Temporary import means bringing into the United States from a foreign country any defense...

22 CFR 41.31 - Temporary visitors for business or pleasure.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Temporary visitors for business or pleasure. 41.31 Section 41.31 Foreign Relations DEPARTMENT OF STATE VISAS VISAS: DOCUMENTATION OF NONIMMIGRANTS UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Temporary Visitors § 41.31 Temporary visitors for...

22 CFR 41.31 - Temporary visitors for business or pleasure.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Temporary visitors for business or pleasure. 41.31 Section 41.31 Foreign Relations DEPARTMENT OF STATE VISAS VISAS: DOCUMENTATION OF NONIMMIGRANTS UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Temporary Visitors § 41.31 Temporary visitors for...

22 CFR 41.31 - Temporary visitors for business or pleasure.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Temporary visitors for business or pleasure. 41.31 Section 41.31 Foreign Relations DEPARTMENT OF STATE VISAS VISAS: DOCUMENTATION OF NONIMMIGRANTS UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Temporary Visitors § 41.31 Temporary visitors for...

22 CFR 41.31 - Temporary visitors for business or pleasure.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Temporary visitors for business or pleasure. 41.31 Section 41.31 Foreign Relations DEPARTMENT OF STATE VISAS VISAS: DOCUMENTATION OF NONIMMIGRANTS UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Temporary Visitors § 41.31 Temporary visitors for...

22 CFR 41.31 - Temporary visitors for business or pleasure.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Temporary visitors for business or pleasure. 41.31 Section 41.31 Foreign Relations DEPARTMENT OF STATE VISAS VISAS: DOCUMENTATION OF NONIMMIGRANTS UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Temporary Visitors § 41.31 Temporary visitors for...

33 CFR 174.29 - Temporary certificate of number.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Temporary certificate of number. 174.29 Section 174.29 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY....29 Temporary certificate of number. A State may issue a temporary certificate of number that is...

33 CFR 174.29 - Temporary certificate of number.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Temporary certificate of number. 174.29 Section 174.29 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY....29 Temporary certificate of number. A State may issue a temporary certificate of number that is...

5 CFR 300.503 - Conditions for using private sector temporaries.

Code of Federal Regulations, 2010 CFR

2010-01-01

... temporaries. 300.503 Section 300.503 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE... help service firm for the brief or intermittent use of the skills of private sector temporaries, when... through the direct appointment of temporary employees within the time available by the date, and for the...

8 CFR 1244.14 - Withdrawal of Temporary Protected Status.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Withdrawal of Temporary Protected Status... JUSTICE IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 1244.14 Withdrawal of Temporary Protected Status. (a) Authority of director. The director may withdraw the status of...

8 CFR 1244.14 - Withdrawal of Temporary Protected Status.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Withdrawal of Temporary Protected Status... JUSTICE IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 1244.14 Withdrawal of Temporary Protected Status. (a) Authority of director. The director may withdraw the status of...

8 CFR 1244.14 - Withdrawal of Temporary Protected Status.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Withdrawal of Temporary Protected Status... JUSTICE IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 1244.14 Withdrawal of Temporary Protected Status. (a) Authority of director. The director may withdraw the status of...

8 CFR 1244.14 - Withdrawal of Temporary Protected Status.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Withdrawal of Temporary Protected Status... JUSTICE IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 1244.14 Withdrawal of Temporary Protected Status. (a) Authority of director. The director may withdraw the status of...

8 CFR 1244.14 - Withdrawal of Temporary Protected Status.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Withdrawal of Temporary Protected Status... JUSTICE IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 1244.14 Withdrawal of Temporary Protected Status. (a) Authority of director. The director may withdraw the status of...

Porosity of temporary denture soft liners containing antifungal agents

PubMed Central

Lima, Jozely Francisca Mello; Maciel, Janaína Gomes; Hotta, Juliana; Vizoto, Ana Carolina Pero; Honório, Heitor Marques; Urban, Vanessa Migliorini; Neppelenbroek, Karin Hermana

2016-01-01

ABSTRACT Incorporation of antifungals in temporary denture soft liners has been recommended for denture stomatitis treatment; however, it may affect their properties. Objective: To evaluate the porosity of a tissue conditioner (Softone) and a temporary resilient liner (Trusoft) modified by minimum inhibitory concentrations (MICs) of antifungal agents for Candida albicans biofilm. Material and Methods: The porosity was measured by water absorption, based on exclusion of the plasticizer effect. Initially, it was determined by sorption isotherms that the adequate storage solution for specimens (65×10×3.3 mm) of both materials was 50% anhydrous calcium chloride (S50). Then, the porosity factor (PF) was calculated for the study groups (n=10) formed by specimens without (control) or with drug incorporation at MICs (nystatin: Ny-0.032 g, chlorhexidine diacetate: Chx-0.064 g, or ketoconazole: Ke-0.128 g each per gram of soft liner powder) after storage in distilled water or S50 for 24 h, seven and 14 d. Data were statistically analyzed by 4-way repeated measures ANOVA and Tukey's test (α=.05). Results: Ke resulted in no significant changes in PF for both liners in water over 14 days (p>0.05). Compared with the controls, Softone and Trusoft PFs were increased at 14-day water immersion only after addition of Ny and Chx, and Chx, respectively (p<0.05). Both materials showed no significant changes in PF in up to 14 days of S50 immersion, compared with the controls (p>0.05). In all experimental conditions, Softone and Trusoft PFs were significantly lower when immersed in S50 compared with distilled water (p<0.05). Conclusions: The addition of antifungals at MICs resulted in no harmful effects for the porosity of both temporary soft liners in different periods of water immersion, except for Chx and Ny in Softone and Chx in Trusoft at 14 days. No deleterious effect was observed for the porosity of both soft liners modified by the drugs at MICs over 14 days of S50 immersion. PMID:27812615

Surgery of adult bilateral vocal fold paralysis in adduction: history and trends.

PubMed

Sapundzhiev, Nikolay; Lichtenberger, György; Eckel, Hans Edmund; Friedrich, Gerhard; Zenev, Ivan; Toohill, Robert J; Werner, Jochen Alfred

2008-12-01

Bilateral vocal fold paralysis (BVFP) in adduction is characterised by inspiratory dyspnea, due to the paramedian position of the vocal folds with narrowing of the airway at the glottic level. The condition is often life threatening and therefore requires surgical intervention to prevent acute asphyxiation or pulmonary consequences of chronic airway obstruction. Aside from corticosteroid administration and intubation, which are only temporary measures, the standard approach for improving respiration is to perform a tracheotomy. Over the past century, a vast majority of surgical interventions have been developed and applied to restore the patency of the airway and achieve decannulation. Surgeons can generally choose for every individual patient from various well-established treatment options, which have a predictable outcome. An overview of the surgical techniques for laryngeal airway enlargement in BVFP is presented. Included are operative techniques, which have found application in clinical practice, and only to a small extent in purely anatomic or animal studies. The focus is on two major groups of interventions--for temporary and for definitive glottic enlargement. The major types of interventions include the following: (1) resection of anatomical structures; (2) retailoring and displacing the existing structures, with minimal tissue removal; (3) displacing existing structures, without tissue resection; (4) restoration or substitution of the missing innervation of the laryngeal musculature. The single interventions of these four major types have always followed the development of the medical equipment and anaesthesia. At the beginning of the twentieth century, when medicine was unable to counteract surgical infection, endoscopic or extramucosal surgical techniques were dominant. In the 1950s, the microscopic endoscopic laryngeal surgery boomed. At the end of the twentieth century many of the classical endoscopic operations were performed either with the help of surgical lasers alone, or in combination with other interventions.

A reversible thermoresponsive sealant for temporary closure of ocular trauma.

PubMed

Bayat, Niki; Zhang, Yi; Falabella, Paulo; Menefee, Roby; Whalen, John J; Humayun, Mark S; Thompson, Mark E

2017-12-06

Open globe injuries are full-thickness injuries sustained to the eye wall (cornea or sclera), which cause immediate drops in intraocular pressure that may lead to retinal detachment and permanent vision loss if not treated rapidly after injury. The current standard of care for open globe injuries consists of suturing the margins closed, but the technique can be time-consuming, requires specialized training and equipment, and can lead to patient discomfort, abrasion, and infection from eye rubbing. We engineered an injectable, thermoresponsive sealant (TRS) and a custom tool to occlude open globe injuries. The smart hydrogel sealant consists of physically cross-linked N -isopropylacrylamide copolymerized with butylacrylate. At low temperatures, it can be injected as a liquid, and when raised to body temperature, a heat-induced gelation converts the hydrogel into a solidified occlusion. The sealant can be repositioned or removed without causing additional trauma via exposure to cold water. In vitro and ex vivo assessments of mechanical adhesion to eye tissue revealed maintenance of intraocular pressure that is five times greater than the physiological range with reversible seal strength comparable to cyanoacrylate (super glue). In vivo assessment in a rabbit model of ocular trauma demonstrated ease of use for TRS deployment, statistically significant improvement in wound sealing, and no evidence of neurotoxicity, retinal tissue degradation, or significant chronic inflammatory response after 30 days of exposure. Given the advantages of body heat-induced gelation, rapid reversible occlusion, and in vivo safety and efficacy, shape-adaptable TRSs have translational potential as smart wound sealants for temporary occlusion of surgical incisions or traumatic injuries. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Roughness and wettability effect on histological and mechanical response of self-drilling orthodontic mini-implants.

PubMed

Espinar-Escalona, Eduardo; Bravo-Gonzalez, Luis-Alberto; Pegueroles, Marta; Gil, Francisco Javier

2016-06-01

Self-drilling orthodontic mini-implants can be used as temporary devices for orthodontic treatments. Our main goal was to evaluate surface characteristics, roughness and wettability, of surface modified mini-implants to increase their stability during orthodontic treatment without inducing bone fracture and tissue destruction during unscrewing. Modified mini-implants by acid etching, grit-blasting and its combination were implanted in 20 New Zealand rabbits during 10 weeks. After that, the bone-to-implant (BIC) parameter was determined and the torque during unscrewing was measured. The surface characteristics, roughness and wettability, were also measured, onto modified Ti c.p. discs. Acid-etched mini-implants (R a ≈ 1.7 μm, contact angle (CA) ≈ 66°) significantly improved the bone-to-implant parameter, 26 %, compared to as-machined mini-implants (R a ≈ 0.3 μm, CA ≈ 68°, BIC = 19 %) due to its roughness. Moreover, this surface treatment did not modify torque during unscrewing due to their statistically similar wettability (p > 0.05). Surface treatments with higher roughness and hydrophobicity (R a ≈ 4.5 μm, CA ≈ 74°) lead to a greater BIC and to a higher removal torque during unscrewing, causing bone fracture, compared to as-machined mini-implants. Based on these in vivo findings, we conclude that acid-etching surface treatment can support temporary anchoring of titanium mini-implants. This treatment represents a step forward in the direction of reducing the time prior to mini-implant loading by increasing their stability during orthodontic treatment, without inducing bone fracture and tissue destruction during unscrewing.

Fully covered self-expandable metal stents (SEMS), partially covered SEMS and self-expandable plastic stents for the treatment of benign esophageal ruptures and anastomotic leaks.

PubMed

van Boeckel, Petra G A; Dua, Kulwinder S; Weusten, Bas L A M; Schmits, Ruben J H; Surapaneni, Naveen; Timmer, Robin; Vleggaar, Frank P; Siersema, Peter D

2012-02-29

Benign esophageal ruptures and anastomotic leaks are life-threatening conditions that are often treated surgically. Recently, placement of partially and fully covered metal or plastic stents has emerged as a minimally invasive treatment option. We aimed to determine the clinical effectiveness of covered stent placement for the treatment of esophageal ruptures and anastomotic leaks with special emphasis on different stent designs. Consecutive patients who underwent placement of a fully covered self-expandable metal stent (FSEMS), a partially covered SEMS (PSEMS) or a self-expanding plastic stent (SEPS) for a benign esophageal rupture or anastomotic leak after upper gastrointestinal surgery in the period 2007-2010 were included. Data on patient demographics, type of lesion, stent placement and removal, clinical success and complications were collected A total of 52 patients received 83 esophageal stents (61 PSEMS, 15 FSEMS, 7 SEPS) for an anastomotic leak (n=32), iatrogenic rupture (n=13), Boerhaave's syndrome (n=4) or other cause (n=3). Endoscopic stent removal was successful in all but eight patients treated with a PSEMS due to tissue ingrowth. Clinical success was achieved in 34 (76%, intention-to-treat: 65%) patients (PSEMS: 73%, FSEMS: 83%, SEPS: 83%) after a median of 1 (range 1-5) stent and a median stenting time of 39 (range 7-120) days. In total, 33 complications in 24 (46%) patients occurred (tissue in- or overgrowth (n=8), stent migration (n=10), ruptured stent cover (all Ultraflex; n=6), food obstruction (n=3), severe pain (n=2), esophageal rupture (n=2), hemorrhage (n=2)). One (2%) patient died of a stent-related cause. Covered stents placed for a period of 5-6 weeks may well be an alternative to surgery for treating benign esophageal ruptures or anastomotic leaks. As efficacy between PSEMS, FSEMS and SEPS is not different, stent choice should depend on expected risks of stent migration (SEPS and FSEMS) and tissue in- or overgrowth (PSEMS).

DNA entropy reveals a significant difference in complexity between housekeeping and tissue specific gene promoters.

PubMed

Thomas, David; Finan, Chris; Newport, Melanie J; Jones, Susan

2015-10-01

The complexity of DNA can be quantified using estimates of entropy. Variation in DNA complexity is expected between the promoters of genes with different transcriptional mechanisms; namely housekeeping (HK) and tissue specific (TS). The former are transcribed constitutively to maintain general cellular functions, and the latter are transcribed in restricted tissue and cells types for specific molecular events. It is known that promoter features in the human genome are related to tissue specificity, but this has been difficult to quantify on a genomic scale. If entropy effectively quantifies DNA complexity, calculating the entropies of HK and TS gene promoters as profiles may reveal significant differences. Entropy profiles were calculated for a total dataset of 12,003 human gene promoters and for 501 housekeeping (HK) and 587 tissue specific (TS) human gene promoters. The mean profiles show the TS promoters have a significantly lower entropy (p<2.2e-16) than HK gene promoters. The entropy distributions for the 3 datasets show that promoter entropies could be used to identify novel HK genes. Functional features comprise DNA sequence patterns that are non-random and hence they have lower entropies. The lower entropy of TS gene promoters can be explained by a higher density of positive and negative regulatory elements, required for genes with complex spatial and temporary expression. Copyright © 2015 Elsevier Ltd. All rights reserved.

Rheology of tissue conditioners.

PubMed

Murata, H; Hamada, T; Djulaeha, E; Nikawa, H

1998-02-01

Tissue conditioners can be used to condition abused tissues, record functional impressions, make temporary relinings, and for other clinical applications, mainly because of their specific viscoelasticity. However, little information is available on the rheology of the materials, manipulation, and suitability for various clinical applications. This study evaluated the gelation times, the viscoelastic properties after gelation of tissue conditioners, and the influence of the powder/liquid (P/L) ratio. Ten tissue conditioners were used and gelation times were obtained with an oscillating rheometer. A series of stress relaxation tests were also conducted to evaluate the viscoelastic properties after gelation and the changes with the passage of time by means of Maxwell model analogies. Significant differences were found in the gelation times and flow properties after gelation among the materials mixed with the P/L ratios recommended by the manufacturers. The flow properties tended to increase with time of storage. Large differences in the limits of the clinically acceptable P/L ratios and the adjustable limits of elasticity and viscosity by altering P/L ratios were found among the materials. The results suggested that each material should be selected according to each clinical purpose because of the wide ranges of viscoelastic properties and changes in viscoelasticity with time among the materials. Furthermore, gelation times and the viscoelastic properties after gelation can be controlled to improve handling and suit various applications by altering the P/L ratios within the acceptable limits.

In vitro characterization of 3D printed scaffolds aimed at bone tissue regeneration.

PubMed

Boga, João C; Miguel, Sónia P; de Melo-Diogo, Duarte; Mendonça, António G; Louro, Ricardo O; Correia, Ilídio J

2018-05-01

The incidence of fractures and bone-related diseases like osteoporosis has been increasing due to aging of the world's population. Up to now, grafts and titanium implants have been the principal therapeutic approaches used for bone repair/regeneration. However, these types of treatment have several shortcomings, like limited availability, risk of donor-to-recipient infection and tissue morbidity. To overcome these handicaps, new 3D templates, capable of replicating the features of the native tissue, are currently being developed by researchers from the area of tissue engineering. These 3D constructs are able to provide a temporary matrix on which host cells can adhere, proliferate and differentiate. Herein, 3D cylindrical scaffolds were designed to mimic the natural architecture of hollow bones, and to allow nutrient exchange and bone neovascularization. 3D scaffolds were produced with tricalcium phosphate (TCP)/alginic acid (AA) using a Fab@home 3D printer. Furthermore, graphene oxide (GO) was incorporated into the structure of some scaffolds to further enhance their mechanical properties. The results revealed that the scaffolds incorporating GO displayed greater porosity, without impairing their mechanical properties. These scaffolds also presented a controlled swelling profile, enhanced biomineralization capacity and were able to increase the Alkaline Phosphatase (ALP) activity. Such characteristics make TCP/AA scaffolds functionalized with GO promising 3D constructs for bone tissue engineering applications. Copyright © 2018 Elsevier B.V. All rights reserved.

Nonlinear permanent migration response to climatic variations but minimal response to disasters

PubMed Central

Bohra-Mishra, Pratikshya; Oppenheimer, Michael; Hsiang, Solomon M.

2014-01-01

We present a microlevel study to simultaneously investigate the effects of variations in temperature and precipitation along with sudden natural disasters to infer their relative influence on migration that is likely permanent. The study is made possible by the availability of household panel data from Indonesia with an exceptional tracking rate combined with frequent occurrence of natural disasters and significant climatic variations, thus providing a quasi-experiment to examine the influence of environment on migration. Using data on 7,185 households followed over 15 y, we analyze whole-household, province-to-province migration, which allows us to understand the effects of environmental factors on permanent moves that may differ from temporary migration. The results suggest that permanent migration is influenced by climatic variations, whereas episodic disasters tend to have much smaller or no impact on such migration. In particular, temperature has a nonlinear effect on migration such that above 25 °C, a rise in temperature is related to an increase in outmigration, potentially through its impact on economic conditions. We use these results to estimate the impact of projected temperature increases on future permanent migration. Though precipitation also has a similar nonlinear effect on migration, the effect is smaller than that of temperature, underscoring the importance of using an expanded set of climatic factors as predictors of migration. These findings on the minimal influence of natural disasters and precipitation on permanent moves supplement previous findings on the significant role of these variables in promoting temporary migration. PMID:24958887

Nonlinear permanent migration response to climatic variations but minimal response to disasters.

PubMed

Bohra-Mishra, Pratikshya; Oppenheimer, Michael; Hsiang, Solomon M

2014-07-08

We present a microlevel study to simultaneously investigate the effects of variations in temperature and precipitation along with sudden natural disasters to infer their relative influence on migration that is likely permanent. The study is made possible by the availability of household panel data from Indonesia with an exceptional tracking rate combined with frequent occurrence of natural disasters and significant climatic variations, thus providing a quasi-experiment to examine the influence of environment on migration. Using data on 7,185 households followed over 15 y, we analyze whole-household, province-to-province migration, which allows us to understand the effects of environmental factors on permanent moves that may differ from temporary migration. The results suggest that permanent migration is influenced by climatic variations, whereas episodic disasters tend to have much smaller or no impact on such migration. In particular, temperature has a nonlinear effect on migration such that above 25 °C, a rise in temperature is related to an increase in outmigration, potentially through its impact on economic conditions. We use these results to estimate the impact of projected temperature increases on future permanent migration. Though precipitation also has a similar nonlinear effect on migration, the effect is smaller than that of temperature, underscoring the importance of using an expanded set of climatic factors as predictors of migration. These findings on the minimal influence of natural disasters and precipitation on permanent moves supplement previous findings on the significant role of these variables in promoting temporary migration.

[Vitamina D. A wonderful drug?].

PubMed

Casado de Frías, Enrique

2011-01-01

During the last years vitamina D receptors have been found in a vast number of tissues and cell types. In paralel, the therapeutic utility of vitamina D has expanded to the prophylaxis of muscular, oncologic, cardiovascular and autoinmmune disorders.

In vivo imaging of coral tissue and skeleton with optical coherence tomography

PubMed Central

Wentzel, Camilla; Jacques, Steven L.; Wagner, Michael

2017-01-01

Application of optical coherence tomography (OCT) for in vivo imaging of tissue and skeleton structure of intact living corals enabled the non-invasive visualization of coral tissue layers (endoderm versus ectoderm), skeletal cavities and special structures such as mesenterial filaments and mucus release from intact living corals. Coral host chromatophores containing green fluorescent protein-like pigment granules appeared hyper-reflective to near-infrared radiation allowing for excellent optical contrast in OCT and a rapid characterization of chromatophore size, distribution and abundance. In vivo tissue plasticity could be quantified by the linear contraction velocity of coral tissues upon illumination resulting in dynamic changes in the live coral tissue surface area, which varied by a factor of 2 between the contracted and expanded state of a coral. Our study provides a novel view on the in vivo organization of coral tissue and skeleton and highlights the importance of microstructural dynamics for coral ecophysiology. PMID:28250104

Directly auto-transplanted mesenchymal stem cells induce bone formation in a ceramic bone substitute in an ectopic sheep model.

PubMed

Boos, Anja M; Loew, Johanna S; Deschler, Gloria; Arkudas, Andreas; Bleiziffer, Oliver; Gulle, Heinz; Dragu, Adrian; Kneser, Ulrich; Horch, Raymund E; Beier, Justus P

2011-06-01

Bone tissue engineering approaches increasingly focus on the use of mesenchymal stem cells (MSC). In most animal transplantation models MSC are isolated and expanded before auto cell transplantation which might be critical for clinical application in the future. Hence this study compares the potential of directly auto-transplanted versus in vitro expanded MSC with or without bone morphogenetic protein-2 (BMP-2) to induce bone formation in a large volume ceramic bone substitute in the sheep model. MSC were isolated from bone marrow aspirates and directly auto-transplanted or expanded in vitro and characterized using fluorescence activated cell sorting (FACS) and RT-PCR analysis before subcutaneous implantation in combination with BMP-2 and β-tricalcium phosphate/hydroxyapatite (β-TCP/HA) granules. Constructs were explanted after 1 to 12 weeks followed by histological and RT-PCR evaluation. Sheep MSC were CD29(+), CD44(+) and CD166(+) after selection by Ficoll gradient centrifugation, while directly auto-transplanted MSC-populations expressed CD29 and CD166 at lower levels. Both, directly auto-transplanted and expanded MSC, were constantly proliferating and had a decreasing apoptosis over time in vivo. Directly auto-transplanted MSC led to de novo bone formation in a heterotopic sheep model using a β-TCP/HA matrix comparable to the application of 60 μg/ml BMP-2 only or implantation of expanded MSC. Bone matrix proteins were up-regulated in constructs following direct auto-transplantation and in expanded MSC as well as in BMP-2 constructs. Up-regulation was detected using immunohistology methods and RT-PCR. Dense vascularization was demonstrated by CD31 immunohistology staining in all three groups. Ectopic bone could be generated using directly auto-transplanted or expanded MSC with β-TCP/HA granules alone. Hence BMP-2 stimulation might become dispensable in the future, thus providing an attractive, clinically feasible approach to bone tissue engineering. © 2011 The Authors Journal of Cellular and Molecular Medicine © 2011 Foundation for Cellular and Molecular Medicine/Blackwell Publishing Ltd.

Strategic planning for post-disaster temporary housing.

PubMed

Johnson, Cassidy

2007-12-01

Temporary housing programmes suffer from excessively high cost, late delivery, poor location, improper unit designs and other inherent issues. These issues can be attributed in part to a prevalence of ad hoc tactical planning, rather than pre-disaster strategic planning, for reconstruction undertaken by governments and non-governmental organisations (NGOs) in the chaotic post-disaster environment. An analysis of the process and outcomes from six case studies of temporary housing programmes after disasters in Turkey and Colombia in 1999, Japan in 1995, Greece in 1986, Mexico in 1985, and Italy in 1976 yields information about the extent to which strategic planning is employed in temporary housing programmes, as well as common issues in temporary housing. Based on an understanding of these common issues, this paper proposes a framework for strategic planning for temporary housing that identifies organisational designs and available resources for temporary housing before the disaster, but allows modifications to fit the specific post-disaster situation.

Traction test of temporary dental cements.

PubMed

Román-Rodríguez, Juan-Luis; Millan-Martínez, Diego; Fons-Font, Antonio; Agustín-Panadero, Rubén; Fernández-Estevan, Lucía

2017-04-01

Classic self-curing temporary cements obstruct the translucence of provisional restorations. New dual-cure esthetic temporary cements need investigation and comparison with classic cements to ensure that they are equally retentive and provide adequate translucence. The objective is to analyze by means of traction testing in a in vitro study the retention of five temporary cements. Ten molars were prepared and ten provisional resin restorations were fabricated using CAD-CAM technology (n=10). Five temporary cements were selected: self-curing temporary cements, Dycal (D), Temp Bond (TB), Temp Bond Non Eugenol (TBNE); dual-curing esthetic cements Temp Bond Clear (TBC) and Telio CS link (TE). Each sample underwent traction testing, both with thermocycling (190 cycles at 5-55º) and without thermocycling. TE and TBC obtained the highest traction resistance values. Thermocycling reduced the resistance of all cements except TBC. The dual-cure esthetic cements tested provided optimum outcomes for bonding provisional restorations. Key words: Temporary dental cements, cements resistance.

Sequential monitoring and stability of ex vivo-expanded autologous and non-autologous regulatory T cells following infusion in non-human primates

PubMed Central

Zhang, H.; Guo, H.; Lu, L.; Zahorchak, A. F.; Wiseman, R. W.; Raimondi, G.; Cooper, D. K. C.; Ezzelarab, M. B.; Thomson, A. W.

2016-01-01

Ex vivo-expanded cynomolgus monkey CD4+CD25+CD127− regulatory T cells (Treg) maintained Foxp3 demethylation status at the Treg-Specific Demethylation Region (TSDR), and potently suppressed T cell proliferation through 3 rounds of expansion. When CFSE- or VPD450-labeled autologous (auto) and non-autologous (non-auto) expanded Treg were infused into monkeys, the number of labeled auto-Treg in peripheral blood declined rapidly during the first week, but persisted at low levels in both normal and anti-thymocyte globulin plus rapamycin-treated (immunosuppressed; IS) animals for at least 3 weeks. By contrast, MHC-mismatched non-auto-Treg could not be detected in normal monkey blood or in blood of two out of the three IS monkeys by day 6 post-infusion. They were also more difficult to detect than auto-Treg in peripheral lymphoid tissue. Both auto- and non-auto-Treg maintained Ki67 expression early after infusion. Sequential monitoring revealed that adoptively-transferred auto-Treg maintained similarly high levels of Foxp3 and CD25 and low CD127 compared with endogenous Treg, although Foxp3 staining diminished over time in these non-transplanted recipients. Thus, infused ex vivo-expanded auto-Treg persist longer than MHC-mismatched non-auto-Treg in blood of non-human primates and can be detected in secondary lymphoid tissue. Host lymphodepletion and rapamycin administration did not consistently prolong the persistence of non-auto-Treg in these sites. PMID:25783759

Expansion of tumor-infiltrating lymphocytes and their potential for application as adoptive cell transfer therapy in human breast cancer.

PubMed

Lee, Hee Jin; Kim, Young-Ae; Sim, Chan Kyu; Heo, Sun-Hee; Song, In Hye; Park, Hye Seon; Park, Suk Young; Bang, Won Seon; Park, In Ah; Lee, Miseon; Lee, Jung Hoon; Cho, Yeon Sook; Chang, Suhwan; Jung, Jaeyun; Kim, Jisun; Lee, Sae Byul; Kim, Sung Youl; Lee, Myeong Sup; Gong, Gyungyub

2017-12-26

Adoptive cell transfer (ACT) of ex vivo expanded tumor-infiltrating lymphocytes (TILs) has been successful in treating a considerable proportion of patients with metastatic melanoma. In addition, some patients with several other solid tumors were recently reported to have benefited clinically from such ACT. However, it remains unclear whether ACT using TILs is broadly applicable in breast cancer, the most common cancer in women. In this study, the utility of TILs as an ACT source in breast cancers was explored by deriving TILs from a large number of breast cancer samples and assessing their biological potentials. We successfully expanded TILs ex vivo under a standard TIL culture condition from over 100 breast cancer samples, including all breast cancer subtypes. We also found that the information about the percentage of TIL and presence of tertiary lymphoid structure in the tumor tissues could be useful for estimating the number of obtainable TILs after ex vivo culture. The ex vivo expanded TILs contained a considerable level of central memory phenotype T cells (about 20%), and a large proportion of TIL samples were reactive to autologous tumor cells in vitro . Furthermore, the in vitro tumor-reactive autologous TILs could also function in vivo in a xenograft mouse model implanted with the primary tumor tissue. Collectively, these results strongly indicate that ACT using ex vivo expanded autologous TILs is a feasible option in treating patients with breast cancer.

Outcomes of Acellular Dermal Matrix for Immediate Tissue Expander Reconstruction with Radiotherapy: A Retrospective Cohort Study.

PubMed

Craig, Elizabeth S; Clemens, Mark W; Koshy, John C; Wren, James; Hong, Zhang; Butler, Charles; Garvey, Patrick; Selber, Jesse; Kronowitz, Steven

2018-05-24

Despite increasing literature support for the use of acellular dermal matrix (ADM) in expander-based breast reconstruction, the effect of ADM on clinical outcomes in the presence of post-mastectomy radiation therapy (PMRT) has not been well described. To analyze the impact ADM plays on clinical outcomes on immediate tissue expander (ITE) reconstruction undergoing PMRT. We retrospectively reviewed patients who underwent ITE breast reconstruction from 2004 to 2014 at MD Anderson Cancer Center. Patients were categorized into four cohorts: ADM, ADM with PMRT, non-ADM, and non-ADM with PMRT. Outcomes and complications were compared between cohorts. Over ten years, 957 patients underwent ITE reconstruction (683 non-ADM, 113 non-ADM with PMRT, 486 ADM, and 88 ADM with PMRT) with 1,370 reconstructions. Overall complication rates for the ADM and non-ADM cohorts were 39.0 and 16.7%, respectively (p <0.001). Within both cohorts, mastectomy skin flap necrosis (MSFN) was the most common complication, followed by infection. ADM use was associated with a significantly higher rate of infections and seromas in both radiated and non-radiated groups; however, when comparing radiated cohorts, the incidence of explantation was significantly lower with the use of ADM. The decision to use ADM for expander-based breast reconstruction should be performed with caution, given higher overall rates of complications, including infections and seromas. There may, however, be a role for ADM in cases requiring PMRT, as the overall incidence of implant failure is lower than non-ADM cases.

Expansion of tumor-infiltrating lymphocytes and their potential for application as adoptive cell transfer therapy in human breast cancer

PubMed Central

Lee, Hee Jin; Kim, Young-Ae; Sim, Chan Kyu; Heo, Sun-Hee; Song, In Hye; Park, Hye Seon; Park, Suk Young; Bang, Won Seon; Park, In Ah; Lee, Miseon; Lee, Jung Hoon; Cho, Yeon Sook; Chang, Suhwan; Jung, Jaeyun; Kim, Jisun; Lee, Sae Byul; Kim, Sung Youl; Lee, Myeong Sup; Gong, Gyungyub

2017-01-01

Adoptive cell transfer (ACT) of ex vivo expanded tumor-infiltrating lymphocytes (TILs) has been successful in treating a considerable proportion of patients with metastatic melanoma. In addition, some patients with several other solid tumors were recently reported to have benefited clinically from such ACT. However, it remains unclear whether ACT using TILs is broadly applicable in breast cancer, the most common cancer in women. In this study, the utility of TILs as an ACT source in breast cancers was explored by deriving TILs from a large number of breast cancer samples and assessing their biological potentials. We successfully expanded TILs ex vivo under a standard TIL culture condition from over 100 breast cancer samples, including all breast cancer subtypes. We also found that the information about the percentage of TIL and presence of tertiary lymphoid structure in the tumor tissues could be useful for estimating the number of obtainable TILs after ex vivo culture. The ex vivo expanded TILs contained a considerable level of central memory phenotype T cells (about 20%), and a large proportion of TIL samples were reactive to autologous tumor cells in vitro. Furthermore, the in vitro tumor-reactive autologous TILs could also function in vivo in a xenograft mouse model implanted with the primary tumor tissue. Collectively, these results strongly indicate that ACT using ex vivo expanded autologous TILs is a feasible option in treating patients with breast cancer. PMID:29371915

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Yoo-Shin; Lee, Tae Hoon; O'Neill, Brian E., E-mail: BEOneill@houstonmethodist.org

Non-lethal hyperthermia is used clinically as adjuvant treatment to radiation, with mixed results. Denaturation of protein during hyperthermia treatment is expected to synergize with radiation damage to cause cell cycle arrest and apoptosis. Alternatively, hyperthermia is known to cause tissue level changes in blood flow, increasing the oxygenation and radiosensitivity of often hypoxic tumors. In this study, we elucidate a third possibility, that hyperthermia alters cellular adhesion and mechanotransduction, with particular impact on the cancer stem cell population. We demonstrate that cell heating results in a robust but temporary loss of cancer cell aggressiveness and metastatic potential in mouse models.more » In vitro, this heating results in a temporary loss in cell mobility, adhesion, and proliferation. Our hypothesis is that the loss of cellular adhesion results in suppression of cancer stem cells and loss of tumor virulence and metastatic potential. Our study suggests that the metastatic potential of cancer is particularly reduced by the effects of heat on cellular adhesion and mechanotransduction. If true, this could help explain both the successes and failures of clinical hyperthermia, and suggest ways to target treatments to those who would most benefit. - Highlights: • Non-lethal hyperthermia treatment of cancer cells is shown to cause a reduction in rates of tumor initiation and metastasis. • Dynamic imaging of cells during heat treatment shows temporary changes in cell shape, cell migration, and cell proliferation. • Loss of adhesion may lead to the observed effect, which may disproportionately impact the tumor initiating cell fraction. • Loss or suppression of the tumor initiating cell fraction results in the observed loss of metastatic potential in vivo. • This result may lead to new approaches to synergizing hyperthermia with surgery, radiation, and chemotherapy.« less

Impact of bisphosphonate drug burden in alveolar bone during orthodontic tooth movement in a rat model: a pilot study.

PubMed

Kaipatur, Neelambar R; Wu, Yuchin; Adeeb, Samer; Stevenson, Thomas R; Major, Paul W; Doschak, Michael R

2013-10-01

The aim of this pilot study was to investigate the effect of long-term bisphosphonate drug use (bone burden) on orthodontic tooth movement in a rat model. Sprague Dawley rats were used for orthodontic protraction of the maxillary first molars with nickel-titanium coil springs and temporary anchorage devices as anchorage. Four groups of 5 rats each were included in the study; the first 2 groups were dosed with alendronate or a vehicle during concurrent orthodontic tooth movement. The third and fourth groups were pretreated for 3 months with alendronate or vehicle injections, and bisphosphonate drug treatment was discontinued before orthodontic tooth movement. Tooth movement measurements were obtained at 0, 4, and 8 weeks using high-resolution in-vivo microcomputed tomography, and the tissues were analyzed with histology and dynamic labeling of bone turnover. Appreciable tooth movement was achieved during the 8-week duration of this study with nickel-titanium coil springs and temporary anchorage devices. Both bisphosphonate treatment groups exhibited reduced tooth movement compared with the vehicle-dosed controls with a tendency toward more severe reduction in the bisphosphonate predosed group. Concurrent dosing of the bisphosphonate drug resulted in 56% and 65% reductions in tooth protraction at the 4-week and 8-week times, respectively. The impact of bisphosphonate bone burden in retarding tooth movement was even greater, with 77% and 86% reductions in tooth movement at 4 and 8 weeks, respectively. In this study, we used a robust rat model of orthodontic tooth movement with temporary anchorage devices. It has provided evidence that the bone burden of previous bisphosphonate use will significantly inhibit orthodontic tooth movement. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

21 CFR 872.3770 - Temporary crown and bridge resin.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Temporary crown and bridge resin. 872.3770 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3770 Temporary crown and bridge resin. (a) Identification. A temporary crown and bridge resin is a device composed of a material, such as...

9 CFR 130.5 - User fees for services at privately owned permanent and temporary import quarantine facilities.

Code of Federal Regulations, 2011 CFR

2011-01-01

... owned permanent and temporary import quarantine facilities. 130.5 Section 130.5 Animals and Animal... User fees for services at privately owned permanent and temporary import quarantine facilities. (a... privately operated permanent or temporary import quarantine facility will be calculated at the hourly user...

9 CFR 130.5 - User fees for services at privately owned permanent and temporary import quarantine facilities.

Code of Federal Regulations, 2013 CFR

2013-01-01

... owned permanent and temporary import quarantine facilities. 130.5 Section 130.5 Animals and Animal... User fees for services at privately owned permanent and temporary import quarantine facilities. (a... privately operated permanent or temporary import quarantine facility will be calculated at the hourly user...

9 CFR 130.5 - User fees for services at privately owned permanent and temporary import quarantine facilities.

Code of Federal Regulations, 2012 CFR

2012-01-01

... owned permanent and temporary import quarantine facilities. 130.5 Section 130.5 Animals and Animal... User fees for services at privately owned permanent and temporary import quarantine facilities. (a... privately operated permanent or temporary import quarantine facility will be calculated at the hourly user...

9 CFR 130.5 - User fees for services at privately owned permanent and temporary import quarantine facilities.

Code of Federal Regulations, 2014 CFR

2014-01-01

... owned permanent and temporary import quarantine facilities. 130.5 Section 130.5 Animals and Animal... User fees for services at privately owned permanent and temporary import quarantine facilities. (a... privately operated permanent or temporary import quarantine facility will be calculated at the hourly user...

9 CFR 130.5 - User fees for services at privately owned permanent and temporary import quarantine facilities.

Code of Federal Regulations, 2010 CFR

2010-01-01

... owned permanent and temporary import quarantine facilities. 130.5 Section 130.5 Animals and Animal... User fees for services at privately owned permanent and temporary import quarantine facilities. (a... privately operated permanent or temporary import quarantine facility will be calculated at the hourly user...

30 CFR 77.601 - Trailing cables or portable cables; temporary splices.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Trailing cables or portable cables; temporary... OF UNDERGROUND COAL MINES Trailing Cables § 77.601 Trailing cables or portable cables; temporary splices. Temporary splices in trailing cables or portable cables shall be made in a workmanlike manner and...

19 CFR 122.188 - Issuance of temporary Customs access seal.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 19 Customs Duties 1 2010-04-01 2010-04-01 false Issuance of temporary Customs access seal. 122.188... temporary Customs access seal. (a) Conditions for issuance. When an approved Customs access seal is required... temporary Customs access seal for his employee. The employer must satisfy the port director that a hardship...

19 CFR 122.188 - Issuance of temporary Customs access seal.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 19 Customs Duties 1 2011-04-01 2011-04-01 false Issuance of temporary Customs access seal. 122.188... temporary Customs access seal. (a) Conditions for issuance. When an approved Customs access seal is required... temporary Customs access seal for his employee. The employer must satisfy the port director that a hardship...

25 CFR 11.607 - Temporary orders and temporary injunctions.

Code of Federal Regulations, 2012 CFR

2012-04-01

...) In a proceeding for dissolution of marriage or for legal separation, either party may move for temporary maintenance or temporary support of a child of the marriage entitled to support. The motion shall... the peace of the other party or of any child; (3) Excluding a party from the family home or from the...

25 CFR 11.607 - Temporary orders and temporary injunctions.

Code of Federal Regulations, 2014 CFR

2014-04-01

...) In a proceeding for dissolution of marriage or for legal separation, either party may move for temporary maintenance or temporary support of a child of the marriage entitled to support. The motion shall... the peace of the other party or of any child; (3) Excluding a party from the family home or from the...

25 CFR 11.607 - Temporary orders and temporary injunctions.

Code of Federal Regulations, 2013 CFR

2013-04-01

...) In a proceeding for dissolution of marriage or for legal separation, either party may move for temporary maintenance or temporary support of a child of the marriage entitled to support. The motion shall... the peace of the other party or of any child; (3) Excluding a party from the family home or from the...

25 CFR 11.607 - Temporary orders and temporary injunctions.

Code of Federal Regulations, 2011 CFR

2011-04-01

...) In a proceeding for dissolution of marriage or for legal separation, either party may move for temporary maintenance or temporary support of a child of the marriage entitled to support. The motion shall... the peace of the other party or of any child; (3) Excluding a party from the family home or from the...

33 CFR 74.01-15 - Charges for placement of temporary aids.

Code of Federal Regulations, 2011 CFR

2011-07-01

... temporary aids. 74.01-15 Section 74.01-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION CHARGES FOR COAST GUARD AIDS TO NAVIGATION WORK Charges to the Public § 74.01-15 Charges for placement of temporary aids. Charges for placement of temporary aids will be...

33 CFR 74.01-15 - Charges for placement of temporary aids.

Code of Federal Regulations, 2012 CFR

2012-07-01

... temporary aids. 74.01-15 Section 74.01-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION CHARGES FOR COAST GUARD AIDS TO NAVIGATION WORK Charges to the Public § 74.01-15 Charges for placement of temporary aids. Charges for placement of temporary aids will be...

33 CFR 74.01-15 - Charges for placement of temporary aids.

Code of Federal Regulations, 2014 CFR

2014-07-01

... temporary aids. 74.01-15 Section 74.01-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION CHARGES FOR COAST GUARD AIDS TO NAVIGATION WORK Charges to the Public § 74.01-15 Charges for placement of temporary aids. Charges for placement of temporary aids will be...

33 CFR 74.01-15 - Charges for placement of temporary aids.

Code of Federal Regulations, 2013 CFR

2013-07-01

... temporary aids. 74.01-15 Section 74.01-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION CHARGES FOR COAST GUARD AIDS TO NAVIGATION WORK Charges to the Public § 74.01-15 Charges for placement of temporary aids. Charges for placement of temporary aids will be...

33 CFR 74.01-15 - Charges for placement of temporary aids.

Code of Federal Regulations, 2010 CFR

2010-07-01

... temporary aids. 74.01-15 Section 74.01-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION CHARGES FOR COAST GUARD AIDS TO NAVIGATION WORK Charges to the Public § 74.01-15 Charges for placement of temporary aids. Charges for placement of temporary aids will be...

Temporary Work and Insecurity in Britain: A Problem Solved?

ERIC Educational Resources Information Center

Green, Francis

2008-01-01

Temporary workers in Britain experience lower job quality. However, the proportion of employees on temporary contracts has fallen since a decade ago to just 5.5% in 2005. There have also been qualitative improvements. Many temporary workers now fall under the protection of the Fixed Term Employees' (Prevention of Less Favourable Treatment)…

21 CFR 872.3770 - Temporary crown and bridge resin.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Temporary crown and bridge resin. 872.3770 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3770 Temporary crown and bridge resin. (a) Identification. A temporary crown and bridge resin is a device composed of a material, such as...

8 CFR 244.14 - Withdrawal of Temporary Protected Status.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Withdrawal of Temporary Protected Status... TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 244.14 Withdrawal of Temporary Protected... Protected Status under section 244 of the Act at any time upon the occurrence of any of the following: (1...

8 CFR 244.14 - Withdrawal of Temporary Protected Status.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Withdrawal of Temporary Protected Status... TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 244.14 Withdrawal of Temporary Protected... Protected Status under section 244 of the Act at any time upon the occurrence of any of the following: (1...

Adipose tissue derived mesenchymal stem cells for musculoskeletal repair in veterinary medicine

PubMed Central

Arnhold, Stefan; Wenisch, Sabine

2015-01-01

Adipose tissue derived stem cells (ASCs) are mesenchymal stem cells which can be obtained from different adipose tissue sources within the body. It is an abundant cell pool, which is easy accessible and the cells can be obtained in large numbers, cultivated and expanded in vitro and prepared for tissue engineering approaches, especially for skeletal tissue repair. In the recent years this cell population has attracted a great amount of attention among researchers in human as well as in veterinary medicine. In the meantime ASCs have been well characterized and their use in regenerative medicine is very well established. This review focuses on the characterization of ASCs for their use for tissue engineering approaches especially in veterinary medicine and also highlights a selection of clinical trials on the basis of ASCs as the relevant cell source. PMID:25973326

Adipose tissue derived mesenchymal stem cells for musculoskeletal repair in veterinary medicine.

PubMed

Arnhold, Stefan; Wenisch, Sabine

2015-01-01

Adipose tissue derived stem cells (ASCs) are mesenchymal stem cells which can be obtained from different adipose tissue sources within the body. It is an abundant cell pool, which is easy accessible and the cells can be obtained in large numbers, cultivated and expanded in vitro and prepared for tissue engineering approaches, especially for skeletal tissue repair. In the recent years this cell population has attracted a great amount of attention among researchers in human as well as in veterinary medicine. In the meantime ASCs have been well characterized and their use in regenerative medicine is very well established. This review focuses on the characterization of ASCs for their use for tissue engineering approaches especially in veterinary medicine and also highlights a selection of clinical trials on the basis of ASCs as the relevant cell source.

[Current status of bone/cartilage tissue engineering towards clinical applications].

PubMed

Ohgushi, Hajime

2014-10-01

Osteo/chondrogenic differentiation capabilities are seen after in vivo implantation of mesenchymal stem cells (MSCs), which are currently used for the patients having bone/cartilage defects. Importantly, the differentiation capabilities are induced by culturing technology, resulting in in vitro bone/cartilage formation. Especially, the in vitro bone tissue is useful for bone tissue regeneration. For cartilage regeneration, culture expanded chondrocytes derived from patient's normal cartilage are also used for the patients having cartilage damages. Recently, the cultured chondrocytes embedded in atelocollagen gel are obtainable as tissue engineered products distributed by Japan Tissue Engineering Co. Ltd. The products are available in the well-regulated hospitals by qualified orthopedic surgeons. The criteria for these hospitals/surgeons have been established. This review paper focuses on current status of bone/cartilage tissue engineering towards clinical applications in Japan.

Type of employment relationship and mortality: prospective study among Finnish employees in 1984-2000.

PubMed

Nätti, Jouko; Kinnunen, Ulla; Mäkikangas, Anne; Mauno, Saija

2009-04-01

The study investigated the relationship between the type of employment (permanent/temporary) contract and mortality. Factors through which temporary employment was expected to be associated with increased mortality were the degree of satisfaction with the uncertainty related to temporary work situation (Study 1) and the voluntary/involuntary basis for temporary work (Study 2). In Study 1 the data consisted of representative survey on Finnish employees in 1984 (n = 4502), which was merged with register-based follow-up data in Statistics Finland covering years 1985-2000. In Study 2 the data consisted of representative survey on Finnish employees in 1990 (n = 3502) with register-based follow-up data covering years 1991-2000. The relative risk of death was examined by conducting Cox proportional hazards analyses for the permanent and the two temporary employment groups, respectively. In Study 1 temporary employees feeling the insecure situation unsatisfactory had a 1.95-fold higher risk of mortality than permanent employees (95% CI 1.13-3.35) after adjusted for background, health- and work-related factors. In Study 2 employees in the position of having a temporary job on the involuntarily basis had a 2.59-fold higher risk of mortality than permanent employees (95% CI 1.16-5.80). The present study confirmed that temporary employees are not a homogeneous group, which holds true even for mortality. Those temporary employees, who either felt the insecure situation unsatisfactory or who worked in temporary work involuntarily, had higher risk of mortality than permanent employees.

Computational Modeling for Enhancing Soft Tissue Image Guided Surgery: An Application in Neurosurgery.

PubMed

Miga, Michael I

2016-01-01

With the recent advances in computing, the opportunities to translate computational models to more integrated roles in patient treatment are expanding at an exciting rate. One area of considerable development has been directed towards correcting soft tissue deformation within image guided neurosurgery applications. This review captures the efforts that have been undertaken towards enhancing neuronavigation by the integration of soft tissue biomechanical models, imaging and sensing technologies, and algorithmic developments. In addition, the review speaks to the evolving role of modeling frameworks within surgery and concludes with some future directions beyond neurosurgical applications.

Tissue Multiplatform-Based Metabolomics/Metabonomics for Enhanced Metabolome Coverage.

PubMed

Vorkas, Panagiotis A; Abellona U, M R; Li, Jia V

2018-01-01

The use of tissue as a matrix to elucidate disease pathology or explore intervention comes with several advantages. It allows investigation of the target alteration directly at the focal location and facilitates the detection of molecules that could become elusive after secretion into biofluids. However, tissue metabolomics/metabonomics comes with challenges not encountered in biofluid analyses. Furthermore, tissue heterogeneity does not allow for tissue aliquoting. Here we describe a multiplatform, multi-method workflow which enables metabolic profiling analysis of tissue samples, while it can deliver enhanced metabolome coverage. After applying a dual consecutive extraction (organic followed by aqueous), tissue extracts are analyzed by reversed-phase (RP-) and hydrophilic interaction liquid chromatography (HILIC-) ultra-performance liquid chromatography coupled to mass spectrometry (UPLC-MS) and nuclear magnetic resonance (NMR) spectroscopy. This pipeline incorporates the required quality control features, enhances versatility, allows provisional aliquoting of tissue extracts for future guided analyses, expands the range of metabolites robustly detected, and supports data integration. It has been successfully employed for the analysis of a wide range of tissue types.

Tissue characterization of brain tumors during and after pion radiation therapy.

PubMed

Boesiger, P; Greiner, R; Schoepflin, R E; Kann, R; Kuenzi, U

1990-01-01

Negative Pi-mesons (pions) are applied at the Paul Scherrer Institute in the radiotherapy of highly malignant gliomas using a dose escalation program. The therapy effects of 7 randomly selected patients were followed up by 62 MRI examinations. The quantification of the effects is based on the relaxation times T1 and T2, which are acquired by a new designed multi-echo multiple saturation recovery imaging technique. As a summary of the results, roughly two reaction types are observed. For both types the relaxation times increase up to two to three months after the radiation therapy. Then in one type (two patients) the T1 and T2 values of the tumors, and of the edemas surrounding the tumors, further increase, indicating an unfavorable prognosis. In the other type (five patients) the relaxation times drop down towards, or even below, their initial values, reflecting the onset of the reparation processes in the tissue. This later behaviour reflects an at least temporary control of the disease; that is, the short term prognosis for these patients is more favorable. It further can be concluded, with respect to our MR parameters, that the radiotolerance of healthy brain tissue is much higher than that of malignant glioma tissue, despite the fact that these tumors are very seldom definitively radiosensible.

[A case of internal carotid artery stenosis with discontinuance of carotid endarterectomy due to the tight adhesions around the internal carotid artery].

PubMed

Kohri, Ryusuke; Miyazono, Masayuki; Hatae, Ryusuke; Maeda, Kazushi; Takahira, Asuka; Maeda, Yasuhiro; Mizota, Takamitsu; Naito, Shinji

2012-05-01

A 73-year-old female visited her local doctor after repeatedly experiencing temporary weakness in her left upper and lower extremities. The patient underwent a cervical magnetic resonance imaging (MRI) scan and was diagnosed with right internal carotid artery stenosis. Despite administration of antiplatelet drugs, her symptoms continued, and she was referred to our department for medical treatment. Her medical history revealed hypertension, hyperlipidemia, and cholesteatoma. We diagnosed symptomatic internal carotid artery stenosis and performed carotid endarterectomy (CEA). However, tight adhesions between the carotid artery and surrounding tissue made separation difficult, and surgery had to be discontinued. Some of the extracted adherent tissue consisted of hyalinized fibrous tissue that had the appearance of soft tissue which had organized because of inflammation. Although there have been no reports of cholesteatoma directly causing adhesion around the internal carotid artery, it has been reported to have led to abscess formation in the parapharyngeal space adjacent to the carotid space. Because the boundaries of the parapharyngeal space and carotid space are anatomically incomplete, inflammation often affects the area between them. As far as we know, this report, which also includes a discussion of the literature, is the first to indicate that cholesteatoma causes strong adhesions around the carotid artery.

Large Scale Expansion of Human Umbilical Cord Cells in a Rotating Bed System Bioreactor for Cardiovascular Tissue Engineering Applications

PubMed Central

Reichardt, Anne; Polchow, Bianca; Shakibaei, Mehdi; Henrich, Wolfgang; Hetzer, Roland; Lueders, Cora

2013-01-01

Widespread use of human umbilical cord cells for cardiovascular tissue engineering requires production of large numbers of well-characterized cells under controlled conditions. In current research projects, the expansion of cells to be used to create a tissue construct is usually performed in static cell culture systems which are, however, often not satisfactory due to limitations in nutrient and oxygen supply. To overcome these limitations dynamic cell expansion in bioreactor systems under controllable conditions could be an important tool providing continuous perfusion for the generation of large numbers of viable pre-conditioned cells in a short time period. For this purpose cells derived from human umbilical cord arteries were expanded in a rotating bed system bioreactor for up to 9 days. For a comparative study, cells were cultivated under static conditions in standard culture devices. Our results demonstrated that the microenvironment in the perfusion bioreactor was more favorable than that of the standard cell culture flasks. Data suggested that cells in the bioreactor expanded 39 fold (38.7 ± 6.1 fold) in comparison to statically cultured cells (31.8 ± 3.0 fold). Large-scale production of cells in the bioreactor resulted in more than 3 x 108 cells from a single umbilical cord fragment within 9 days. Furthermore cell doubling time was lower in the bioreactor system and production of extracellular matrix components was higher. With this study, we present an appropriate method to expand human umbilical cord artery derived cells with high cellular proliferation rates in a well-defined bioreactor system under GMP conditions. PMID:23847691

Differential effect of subcutaneous abdominal and visceral adipose tissue on cardiometabolic risk.

PubMed

Sam, Susan

2018-03-09

Metabolic and cardiovascular diseases are increasing worldwide due to the rise in the obesity epidemic. The metabolic consequences of obesity vary by distribution of adipose tissue. Visceral and ectopic adipose accumulation are associated with adverse cardiometabolic consequences, while gluteal-femoral adipose accumulation are negatively associated with these adverse complications and subcutaneous abdominal adipose accumulation is more neutral in its associations. Gender, race and ethnic differences in adipose tissue distribution have been described and could account for the observed differences in risk for cardiometabolic disease. The mechanisms behind the differential impact of adipose tissue on cardiometabolic risk have started to be unraveled and include differences in adipocyte biology, inflammatory profile, connection to systemic circulation and most importantly the inability of the subcutaneous adipose tissue to expand in response to positive energy balance.

Temporary Contracts: Effect on Job Satisfaction and Personal Lives of Recent Phd Graduates

ERIC Educational Resources Information Center

Waaijer, Cathelijn J. F.; Belder, Rosalie; Sonneveld, Hans; van Bochove, Cornelis A.; van der Weijden, Inge C. M.

2017-01-01

In this study, we assess the effects of temporary employment on job satisfaction and the personal lives of recent PhD graduates. Temporary employment is becoming increasingly prevalent in many sectors, but has been relatively common in academia, especially for early career scientists. Labor market theory shows temporary employment to have a…

40 CFR 180.1301 - Escherichia coli O157:H7 specific bacteriophages; temporary exemption from the requirement of a...

Code of Federal Regulations, 2011 CFR

2011-07-01

... bacteriophages; temporary exemption from the requirement of a tolerance. 180.1301 Section 180.1301 Protection of... bacteriophages; temporary exemption from the requirement of a tolerance. A temporary exemption from the requirement of a tolerance is established for residues of lytic bacteriophages that are specific to...

40 CFR 180.1301 - Escherichia coli O157:H7 specific bacteriophages; temporary exemption from the requirement of a...

Code of Federal Regulations, 2014 CFR

2014-07-01

... bacteriophages; temporary exemption from the requirement of a tolerance. 180.1301 Section 180.1301 Protection of... bacteriophages; temporary exemption from the requirement of a tolerance. A temporary exemption from the requirement of a tolerance is established for residues of lytic bacteriophages that are specific to...

40 CFR 180.1301 - Escherichia coli O157:H7 specific bacteriophages; temporary exemption from the requirement of a...

Code of Federal Regulations, 2013 CFR

2013-07-01

... bacteriophages; temporary exemption from the requirement of a tolerance. 180.1301 Section 180.1301 Protection of... bacteriophages; temporary exemption from the requirement of a tolerance. A temporary exemption from the requirement of a tolerance is established for residues of lytic bacteriophages that are specific to...

40 CFR 180.1301 - Escherichia coli O157:H7 specific bacteriophages; temporary exemption from the requirement of a...

Code of Federal Regulations, 2012 CFR

2012-07-01

... bacteriophages; temporary exemption from the requirement of a tolerance. 180.1301 Section 180.1301 Protection of... bacteriophages; temporary exemption from the requirement of a tolerance. A temporary exemption from the requirement of a tolerance is established for residues of lytic bacteriophages that are specific to...

The Temporary Help Industry: A Response to the Dual Internal Labor Market.

ERIC Educational Resources Information Center

Mangum, Garth; And Others

1985-01-01

This study of the rapidly growing temporary help industry draws on Commerce Department data and the results of the authors' national mail survey of employers. The authors also conducted interviews in the San Francisco area with employers of temporary help and with representatives of temporary help agencies and labor unions. (Author/CT)

46 CFR 112.15-10 - Loads on systems without a temporary emergency power source.

Code of Federal Regulations, 2013 CFR

2013-10-01

...) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Loads § 112.15-10 Loads on systems without a temporary emergency power source. If there is no temporary emergency power source, the loads... 46 Shipping 4 2013-10-01 2013-10-01 false Loads on systems without a temporary emergency power...

46 CFR 112.15-10 - Loads on systems without a temporary emergency power source.

Code of Federal Regulations, 2014 CFR

2014-10-01

...) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Loads § 112.15-10 Loads on systems without a temporary emergency power source. If there is no temporary emergency power source, the loads... 46 Shipping 4 2014-10-01 2014-10-01 false Loads on systems without a temporary emergency power...

46 CFR 112.15-10 - Loads on systems without a temporary emergency power source.

Code of Federal Regulations, 2012 CFR

2012-10-01

...) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Loads § 112.15-10 Loads on systems without a temporary emergency power source. If there is no temporary emergency power source, the loads... 46 Shipping 4 2012-10-01 2012-10-01 false Loads on systems without a temporary emergency power...

46 CFR 112.15-10 - Loads on systems without a temporary emergency power source.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Loads § 112.15-10 Loads on systems without a temporary emergency power source. If there is no temporary emergency power source, the loads... 46 Shipping 4 2011-10-01 2011-10-01 false Loads on systems without a temporary emergency power...

46 CFR 112.15-10 - Loads on systems without a temporary emergency power source.

Code of Federal Regulations, 2010 CFR

2010-10-01

...) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Loads § 112.15-10 Loads on systems without a temporary emergency power source. If there is no temporary emergency power source, the loads... 46 Shipping 4 2010-10-01 2010-10-01 false Loads on systems without a temporary emergency power...

27 CFR 6.85 - Temporary retailers.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Temporary retailers. 6.85 Section 6.85 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS âTIED-HOUSEâ Exceptions § 6.85 Temporary retailers. (a) General. The furnishing of things of value to a temporary...

27 CFR 6.85 - Temporary retailers.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Temporary retailers. 6.85 Section 6.85 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS âTIED-HOUSEâ Exceptions § 6.85 Temporary retailers. (a) General. The furnishing of things of value to a temporary...

17 CFR 201.540 - Appeal and Commission review of initial decision making a temporary order permanent.

Code of Federal Regulations, 2010 CFR

2010-04-01

... of initial decision making a temporary order permanent. 201.540 Section 201.540 Commodity and... Temporary Orders and Suspensions § 201.540 Appeal and Commission review of initial decision making a... decision as to whether a temporary sanction shall be made permanent shall file a petition for review...

[The morbidity of population temporary disability in the Russian Federation].

PubMed

Shchepin, V O

2012-01-01

The article presents the results of calculation and analysis of structure and rate of temporary disability morbidity in the Russian Federation in 2007-2010. The quality assessment of the indicators of temporary disability morbidity is given. The financial volumes of work losses and costs of medical care and disease social insurance are established. The significant gender differences in rate and temporary disability duration are demonstrated. The issues demanding a specific approach during the development of activities targeted to prevention and decrease of temporary disability morbidity are discussed.

Penile enhancement using autologous tissue engineering with biodegradable scaffold: a clinical and histomorphometric study.

PubMed

Perovic, Sava V; Sansalone, Salvatore; Djinovic, Rados; Ferlosio, Amedeo; Vespasiani, Giuseppe; Orlandi, Augusto

2010-09-01

Autologous tissue engineering with biodegradable scaffolds is a new treatment option for real penile girth enhancement. The aim of this article is to evaluate tissue remodeling after penile girth enhancement using this technique. Between June 2005 and May 2007, a group of 12 patients underwent repeated penile widening using biodegradable scaffolds enriched with expanded autologous scrotal dartos cells. Clinical monitoring was parallel to histological investigation of tissue remodeling. During second surgical procedure, biopsies were obtained 10-14 months after first surgery (mean 12 months, N=6) and compared with those obtained after 22-24 months (mean 23 months, N=6), and control biopsies from patients who underwent circumcision (N=5). Blind evaluation of histomorphometrical and immunohistochemical finding was performed in paraffin sections. Penile girth gain in a flaccid state ranged between 1.5 and 3.8 cm (mean 2.1 ± 0.28 cm) and in full erection between 1.2 and 4 cm (mean 1.9 ± 0.28 cm). Patients' satisfaction, defined by a questionnaire, was good (25%) and very good (75%). In biopsies obtained 10-14 months after first surgery, highly vascularized loose tissue with collagen deposition associated with small foci of mild chronic and granulomatous inflammation surrounding residual amorphous material was observed. Fibroblast-like hyperplasia and small vessel neoangiogenesis occurred intimately associated with the progressive growth of vascular-like structures from accumulation of CD34 and alpha-smooth muscle actin-positive cells surrounding residual scaffold-like amorphous material. Capillary neoangiogenesis occurred inside residual amorphous material. In biopsies obtained after 22-24 months, inflammation almost disappeared and tissue closely resembled that of the dartos fascia of control group. Autologous tissue engineering using expanded scrotal dartos cells with biodegradable scaffolds is a new and promising method for penile widening that generates progressive accumulation of stable collagen-rich, highly vascularized tissue matrix that closely resemble deep dartos fascia. © 2009 International Society for Sexual Medicine.

Laser, light, and energy devices for cellulite and lipodystrophy.

PubMed

Peterson, Jennifer D; Goldman, Mitchel P

2011-07-01

Cellulite affects all races, and it is estimated that 85% of women older than 20 years have some degree of cellulite. Many currently accepted cellulite therapies target deficiencies in lymphatic drainage and microvascular circulation. Devices using radiofrequency, laser, and light-based energies, alone or in combination and coupled frequently with tissue manipulation, are available for improving cellulite. Laser assisted liposuction may improve cellulite appearance. Although improvement using these devices is temporary, it may last several months. Patients who want smoother skin with less visible cellulite can undergo a series of treatments and then return for additional treatments as necessary. Copyright © 2011 Elsevier Inc. All rights reserved.

The use of a silicon sheet for gradual wound closure after fasciotomy.

PubMed

Walker, Tobias; Gruler, Miriam; Ziemer, Gerhard; Bail, Dorothee H L

2012-06-01

We present a silicon sheet for temporary wound covering and gradual wound closure after open fasciotomy. Fasciotomy was performed in a total of 70 limbs with compartment syndrome (CS). The main etiology of CS was predominantly vascular. All patients were treated with a silicon sheet to cover the soft tissue defect and gradually reapproximate the skin margins. In 53% of the patients, a delayed final wound closure was achieved after a mean of 11.9 days. This method allows final closure of fasciotomy wounds without scar contractures, marginal necrosis, infection, or significant pain. Copyright © 2012 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

Iodide Protects Heart Tissue from Reperfusion Injury

PubMed Central

Iwata, Akiko; Morrison, Michael L.; Roth, Mark B.

2014-01-01

Iodine is an elemental nutrient that is essential for mammals. Here we provide evidence for an acute therapeutic role for iodine in ischemia reperfusion injury. Infusion of the reduced form, iodide, but not the oxidized form iodate, reduces heart damage by as much as 75% when delivered intravenously following temporary loss of blood flow but prior to reperfusion of the heart in a mouse model of acute myocardial infarction. Normal thyroid function may be required because loss of thyroid activity abrogates the iodide benefit. Given the high degree of protection and the high degree of safety, iodide should be explored further as a therapy for reperfusion injury. PMID:25379708

Particle Based Technologies for Osteoarthritis Detection and Therapy

PubMed Central

Kavanaugh, Taylor E.; Werfel, Thomas A.; Cho, Hongsik; Hasty, Karen A.; Duvall, Craig L.

2015-01-01

Osteoarthritis (OA) is a disease characterized by degradation of joints with the development of painful osteophytes in the surrounding tissues. Currently, there are a limited number of treatments for this disease and many of these only provide temporary, palliative relief. In this review, we discuss polymer drug delivery systems that can provide targeted and sustained delivery of imaging and therapeutic agents to OA-affected sites. We focus on technologies such as polymeric micelles and nano- / micro-particles, liposomes, and dendrimers for their potential treatment and/or diagnosis of OA. Several promising studies are highlighted, motivating the continued development of delivery technologies to improve treatments for OA. PMID:25990835

[Pathophysiology, prophylaxis and treatment of reperfusion syndrome in the surgery of abdominal aorta aneurysm].

PubMed

Sukharev, I I; Guch, A A; Medvedskyĭ, E B; Kostylev, M V; Kornitskaia, A I; Gindich, L A; Dominiak, A B; Vlaĭkov, G G

1999-01-01

The peroxidal oxidation of the lipids state was studied up, as well as of the whole blood neutrophils functional activity, hemodynamics and microcirculation of lower extremities in surgical treatment of the abdominal aorta aneurysm. The main significance in the reperfusional syndrome pathophysiology, caused by temporary overcompression of aorta, has the neutrophils activation, their interrelationship with the endothelium cells and the activity lowering of the tissue antioxidant system, manifestated by vascular spasm, which is mostly expressed in the patients with stenotic affection of the lower extremities arteries. Positive effect was noted in application of preparation corvitin, which has antioxidant action.

Micropropagation systems of Feijoa (Acca sellowiana (O. Berg) Burret).

PubMed

Guerra, Miguel Pedro; Cangahuala-Inocente, Gabriela Claudia; Vesco, Lirio Luiz Dal; Pescador, Rosete; Caprestano, Clarissa Alves

2013-01-01

Acca sellowiana (O. Berg) Burret sin. Feijoa sellowiana (Myrtaceae) is a semiwoody fruit species native to South Brazil, Uruguay, and Argentina; edible fruits are tasty. The naturally occurring populations in Santa Catarina State show high variability in fruit size, color, and other features. A breeding program launched in 1990 resulted in the release of four Brazilian commercial varieties. The conventional clonal propagation methods of this species, such as cutting and grafting, have shown low efficiency. Therefore, tissue culture techniques were developed for mass propagation. This chapter describes several protocols based on organogenesis and somatic embryogenesis. Additional techniques including synthetic seed technology and temporary immersion system are also described.

A Systematic Review and Head-to-Head Meta-Analysis of Outcomes following Direct-to-Implant versus Conventional Two-Stage Implant Reconstruction.

PubMed

Basta, Marten N; Gerety, Patrick A; Serletti, Joseph M; Kovach, Stephen J; Fischer, John P

2015-12-01

Innovative approaches to reconstruction have ushered in an era of breast reconstruction in which direct-to-implant procedures can provide an immediately reconstructed breast. Balancing the benefits against its technical challenges is vital. The authors evaluated the safety and efficacy of using direct-to-implant versus conventional two-stage reconstruction through a systematic meta-analysis. A literature search identified all articles published after 1999 involving prosthetic-based breast reconstruction as a two-stage tissue expander/implant or direct-to-implant technique. The primary outcomes of interest, including implant loss, capsular contracture, reoperation, and infection, were analyzed by means of head-to-head meta-analysis. Thirteen studies involving 5216 breast reconstructions were included. The average patient age was 47.2 ± 1.0 years, the average body mass index was 24.9 ± 0.8 mg/k2, and the average follow-up was 40.8 months. Wound infection, seroma, and capsular contracture risk were similar between groups. However, direct-to-implant reconstruction was associated with a higher risk for skin flap necrosis (OR, 1.43; p = 0.01; I2 = 51 percent) and reoperation (OR, 1.25; p = 0.04; I2 = 43 percent). Ultimately, the risk for implant loss was nearly two-fold higher with direct-to-implant reconstruction compared with tissue expander/implant reconstruction (OR, 1.87; p = 0.04; I2 = 33 percent). Although direct-to-implant and two-stage tissue expander/implant reconstruction are successful approaches, this meta-analysis demonstrates significantly greater risk of flap necrosis and implant failure with direct-to-implant reconstruction. The authors' findings suggest that the critical component of patient selection is judgment of mastectomy flap tissue quality. These findings can enhance the risk counseling process and highlight the need for additional investigations to optimize outcomes.

Migration of bone marrow and cord blood mesenchymal stem cells in vitro is regulated by stromal-derived factor-1-CXCR4 and hepatocyte growth factor-c-met axes and involves matrix metalloproteinases.

PubMed

Son, Bo-Ra; Marquez-Curtis, Leah A; Kucia, Magda; Wysoczynski, Marcin; Turner, A Robert; Ratajczak, Janina; Ratajczak, Mariusz Z; Janowska-Wieczorek, Anna

2006-05-01

Human mesenchymal stem cells (MSCs) are increasingly being considered in cell-based therapeutic strategies for regeneration of various organs/tissues. However, the signals required for their homing and recruitment to injured sites are not yet fully understood. Because stromal-derived factor (SDF)-1 and hepatocyte growth factor (HGF) become up-regulated during tissue/organ damage, in this study we examined whether these factors chemoattract ex vivo-expanded MSCs derived from bone marrow (BM) and umbilical cord blood (CB). Specifically, we investigated the expression by MSCs of CXCR4 and c-met, the cognate receptors of SDF-1 and HGF, and their functionality after early and late passages of MSCs. We also determined whether MSCs express matrix metalloproteinases (MMPs), including membrane type 1 (MT1)-MMP, matrix-degrading enzymes that facilitate the trafficking of hematopoietic stem cells. We maintained expanded BM- or CB-derived MSCs for up to 15-18 passages with monitoring of the expression of 1) various tissue markers (cardiac and skeletal muscle, neural, liver, and endothelial cells), 2) functional CXCR4 and c-met, and 3) MMPs. We found that for up to 15-18 passages, both BM- and CB-derived MSCs 1) express mRNA for cardiac, muscle, neural, and liver markers, as well as the vascular endothelial (VE) marker VE-cadherin; 2) express CXCR4 and c-met receptors and are strongly attracted by SDF-1 and HGF gradients; 3) express MMP-2 and MT1-MMP transcripts and proteins; and 4) are chemo-invasive across the reconstituted basement membrane Matrigel. These in vitro results suggest that the SDF-1-CXCR4 and HGF-c-met axes, along with MMPs, may be involved in recruitment of expanded MSCs to damaged tissues.

Temporary implant-supported prosthesis for immediate loading according to a chair-side concept: technical note and results from 37 consecutive cases.

PubMed

Ostman, Pär-Olov; Hellman, Mats; Sennerby, Lars; Wennerberg, Ann

2008-05-01

During the last years, focus has been paid to implant treatment using immediate function protocols, and different approaches to provide patients with temporary constructions have been presented. Most of these techniques involve dental technicians producing the temporary construction, for example, rebuilding existing dentures, acrylic bridges, etc. The purpose of this prospective clinical study was to evaluate the clinical outcome of a chair-side technique of a cost-effective temporary prosthesis. Fixture survival rate and risk of temporary bridge failure were analyzed. Thirty-seven partially or totally edentate patients (18 female and 19 male; mean age: 66.7 years) treated with chair-side manufactured temporary restorations (QuickBridge, BIOMET 3i, Palm Beach, Fl, USA) for immediate loading have been evaluated. The prostheses extended from two unit bridges supported by two implants to full-arch construction supported by six implants. The temporary prostheses were monitored from the day of surgery and delivery to the time of replacement with a permanent prosthetic construction 3 to 6 months later. No implants were lost during the observation time. One (3%) temporary prosthesis fractured and additional two (6%) loosened during the follow-up time. The study indicated that the tested chair-side concept for manufacturing of temporary prosthesis for immediate loading of dental implants is a viable approach.

78 FR 39062 - Group Lotus plc; Modification of a Temporary Exemption From an Advanced Air Bag Requirement of...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-28

...-0086] Group Lotus plc; Modification of a Temporary Exemption From an Advanced Air Bag Requirement of... temporary exemption granted to Group Lotus plc (Lotus) on March 8, 2013. The agency granted Lotus an... Lotus Plc (Lotus) a temporary exemption from the higher maximum speed (56 km/h (35 mph)) belted test...

26 CFR 1.267(a)-2T - Temporary regulations; questions and answers arising under the Tax Reform Act of 1984 (temporary).

Code of Federal Regulations, 2010 CFR

2010-04-01

... Act of 1984 (temporary). (a) Introduction—(1) Scope. This section prescribes temporary question and... the person to whom the payment is to be made properly uses the completed contract method of accounting... amount is owed to a related person under whose method of accounting such amount is not includible in...

77 FR 12723 - Labor Certification Process for the Temporary Employment of Aliens in Agriculture in the United...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-02

... the Temporary Employment of Aliens in Agriculture in the United States; Announcement of Non- Material... reasons in great detail in the preamble of the ``Temporary Agricultural Employment of H-2A Aliens in the... set the AEWR. See ``Temporary Agricultural Employment of H-2A Aliens in the United States; Modernizing...

41 CFR 302-3.400 - What is a “temporary change of station (TCS)”?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 4 2010-07-01 2010-07-01 false What is a âtemporary change of station (TCS)â? 302-3.400 Section 302-3.400 Public Contracts and Property Management Federal... TYPE Employee's Temporary Change Of Station § 302-3.400 What is a “temporary change of station (TCS...

26 CFR 1.181-0T - Table of contents (temporary).

Code of Federal Regulations, 2010 CFR

2010-04-01

... 26 Internal Revenue 3 2010-04-01 2010-04-01 false Table of contents (temporary). 1.181-0T Section...-0T Table of contents (temporary). This section lists the table of contents for §§ 1.181-1T through 1... deduction allowed. § 1.181-2TElection (temporary). (a) Time and manner of making election. (b) Election by...

20 CFR 1002.41 - Does an employee have rights under USERRA even though he or she holds a temporary, part-time...

Code of Federal Regulations, 2010 CFR

2010-04-01

... even though he or she holds a temporary, part-time, probationary, or seasonal employment position? 1002... employee have rights under USERRA even though he or she holds a temporary, part-time, probationary, or seasonal employment position? USERRA rights are not diminished because an employee holds a temporary, part...

41 CFR 302-3.400 - What is a “temporary change of station (TCS)”?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 41 Public Contracts and Property Management 4 2011-07-01 2011-07-01 false What is a âtemporary change of station (TCS)â? 302-3.400 Section 302-3.400 Public Contracts and Property Management Federal... TYPE Employee's Temporary Change Of Station § 302-3.400 What is a “temporary change of station (TCS...

Extracellular matrix and α5β1 integrin signaling control the maintenance of bone formation capacity by human adipose-derived stromal cells

PubMed Central

Di Maggio, Nunzia; Martella, Elisa; Frismantiene, Agne; Resink, Therese J.; Schreiner, Simone; Lucarelli, Enrico; Jaquiery, Claude; Schaefer, Dirk J.; Martin, Ivan; Scherberich, Arnaud

2017-01-01

Stromal vascular fraction (SVF) cells of human adipose tissue have the capacity to generate osteogenic grafts with intrinsic vasculogenic properties. However, adipose-derived stromal/stem cells (ASC), even after minimal monolayer expansion, display poor osteogenic capacity in vivo. We investigated whether ASC bone-forming capacity may be maintained by culture within a self-produced extracellular matrix (ECM) that recapitulates the native environment. SVF cells expanded without passaging up to 28 days (Unpass-ASC) deposited a fibronectin-rich extracellular matrix and displayed greater clonogenicity and differentiation potential in vitro compared to ASC expanded only for 6 days (P0-ASC) or for 28 days with regular passaging (Pass-ASC). When implanted subcutaneously, Unpass-ASC produced bone tissue similarly to SVF cells, in contrast to P0- and Pass-ASC, which mainly formed fibrous tissue. Interestingly, clonogenic progenitors from native SVF and Unpass-ASC expressed low levels of the fibronectin receptor α5 integrin (CD49e), which was instead upregulated in P0- and Pass-ASC. Mechanistically, induced activation of α5β1 integrin in Unpass-ASC led to a significant loss of bone formation in vivo. This study shows that ECM and regulation of α5β1-integrin signaling preserve ASC progenitor properties, including bone tissue-forming capacity, during in vitro expansion. PMID:28290502

Zebrafish Caudal Haematopoietic Embryonic Stromal Tissue (CHEST) Cells Support Haematopoiesis.

PubMed

Wolf, Anja; Aggio, Julian; Campbell, Clyde; Wright, Francis; Marquez, Gabriel; Traver, David; Stachura, David L

2017-03-16

Haematopoiesis is an essential process in early vertebrate development that occurs in different distinct spatial locations in the embryo that shift over time. These different sites have distinct functions: in some anatomical locations specific hematopoietic stem and progenitor cells (HSPCs) are generated de novo. In others, HSPCs expand. HSPCs differentiate and renew in other locations, ensuring homeostatic maintenance. These niches primarily control haematopoiesis through a combination of cell-to-cell signalling and cytokine secretion that elicit unique biological effects in progenitors. To understand the molecular signals generated by these niches, we report the generation of caudal hematopoietic embryonic stromal tissue (CHEST) cells from 72-hours post fertilization (hpf) caudal hematopoietic tissue (CHT), the site of embryonic HSPC expansion in fish. CHEST cells are a primary cell line with perivascular endothelial properties that expand hematopoietic cells in vitro. Morphological and transcript analysis of these cultures indicates lymphoid, myeloid, and erythroid differentiation, indicating that CHEST cells are a useful tool for identifying molecular signals critical for HSPC proliferation and differentiation in the zebrafish. These findings permit comparison with other temporally and spatially distinct haematopoietic-supportive zebrafish niches, as well as with mammalian haematopoietic-supportive cells to further the understanding of the evolution of the vertebrate hematopoietic system.

Tissue-engineered human bioartificial muscles expressing a foreign recombinant protein for gene therapy

NASA Technical Reports Server (NTRS)

Powell, C.; Shansky, J.; Del Tatto, M.; Forman, D. E.; Hennessey, J.; Sullivan, K.; Zielinski, B. A.; Vandenburgh, H. H.

1999-01-01

Murine skeletal muscle cells transduced with foreign genes and tissue engineered in vitro into bioartificial muscles (BAMs) are capable of long-term delivery of soluble growth factors when implanted into syngeneic mice (Vandenburgh et al., 1996b). With the goal of developing a therapeutic cell-based protein delivery system for humans, similar genetic tissue-engineering techniques were designed for human skeletal muscle stem cells. Stem cell myoblasts were isolated, cloned, and expanded in vitro from biopsied healthy adult (mean age, 42 +/- 2 years), and elderly congestive heart failure patient (mean age, 76 +/- 1 years) skeletal muscle. Total cell yield varied widely between biopsies (50 to 672 per 100 mg of tissue, N = 10), but was not significantly different between the two patient groups. Percent myoblasts per biopsy (73 +/- 6%), number of myoblast doublings prior to senescence in vitro (37 +/- 2), and myoblast doubling time (27 +/- 1 hr) were also not significantly different between the two patient groups. Fusion kinetics of the myoblasts were similar for the two groups after 20-22 doublings (74 +/- 2% myoblast fusion) when the biopsy samples had been expanded to 1 to 2 billion muscle cells, a number acceptable for human gene therapy use. The myoblasts from the two groups could be equally transduced ex vivo with replication-deficient retroviral expression vectors to secrete 0.5 to 2 microg of a foreign protein (recombinant human growth hormone, rhGH)/10(6) cells/day, and tissue engineered into human BAMs containing parallel arrays of differentiated, postmitotic myofibers. This work suggests that autologous human skeletal myoblasts from a potential patient population can be isolated, genetically modified to secrete foreign proteins, and tissue engineered into implantable living protein secretory devices for therapeutic use.

Traction test of temporary dental cements

PubMed Central

Millan-Martínez, Diego; Fons-Font, Antonio; Agustín-Panadero, Rubén; Fernández-Estevan, Lucía

2017-01-01

Background Classic self-curing temporary cements obstruct the translucence of provisional restorations. New dual-cure esthetic temporary cements need investigation and comparison with classic cements to ensure that they are equally retentive and provide adequate translucence. The objective is to analyze by means of traction testing in a in vitro study the retention of five temporary cements. Material and Methods Ten molars were prepared and ten provisional resin restorations were fabricated using CAD-CAM technology (n=10). Five temporary cements were selected: self-curing temporary cements, Dycal (D), Temp Bond (TB), Temp Bond Non Eugenol (TBNE); dual-curing esthetic cements Temp Bond Clear (TBC) and Telio CS link (TE). Each sample underwent traction testing, both with thermocycling (190 cycles at 5-55º) and without thermocycling. Results TE and TBC obtained the highest traction resistance values. Thermocycling reduced the resistance of all cements except TBC. Conclusions The dual-cure esthetic cements tested provided optimum outcomes for bonding provisional restorations. Key words:Temporary dental cements, cements resistance. PMID:28469824

Gender, migration, risky sex, and HIV infection in China.

PubMed

Yang, Xiushi; Xia, Guomei

2006-12-01

Gender differences in sexual behavior as a consequence of migration have been ignored in both the migration and the HIV literature in China. This study examines differences among temporary migrants in terms of sexual behavior and factors that make female migrants more vulnerable to the risk of acquiring HIV infection. Results suggest that the interplay of migration and gender renders female temporary migrants particularly vulnerable to engaging in casual and commercial sex. Although male temporary migrants do not differ from male nonmigrants in prevalence of casual and commercial sex, the prevalence rates of casual and commercial sex for female temporary migrants are found to be 14 and 80 times those for female nonmigrants, respectively. Female temporary migrants' higher unemployment rate and concentration in the service and entertainment sectors are keys to understanding differences in the prevalence of casual and commercial sex among temporary migrants according to sex. Policy measures to promote female temporary migrants' equal access to employment are urgently needed to improve their economic well-being and to reduce their risky sexual behavior.

Predictors of sustained organizational commitment among nurses with temporary job contracts.

PubMed

Jalonen, Paivi; Virtanen, Marianna; Vahtera, Jussi; Elovainio, Marko; Kivimaki, Mika

2006-05-01

To examine sociodemographic, work-related factors and psychological health as predictors of sustained organizational commitment among temporary hospital employees. The participants were 412 nurses who had a temporary job contract and reported being committed to their organization at baseline. Organizational commitment was measured again 2 years later. The results of logistic regression analysis showed that age over 35 years, high job control, high participative safety, high perceived justice in decision making, and low psychological distress predicted sustained organizational commitment at follow-up. The change from temporary employment to a permanent job and high job control predicted sustained organizational commitment even after the effect of all the other predictors was taken into account. Organizations that employ temporary workers should pay attention to the job control and career prospects of temporary staff.

A New Paradigm for Biospecimen Banking in the Personalized Medicine Era

PubMed Central

McDonald, Sandra A.; Watson, Mark A.; Rossi, Joan; Becker, Colleen M.; Jaques, David P.; Pfeifer, John D.

2012-01-01

Banking of high-quality, appropriately consented human tissue is crucial for the understanding of disease pathogenesis and translation of such knowledge into improvements in patient care. Traditionally, tissue banking has been thought of as primarily an academic research activity, but tissue and biospecimen banking is increasingly assuming clinical importance, especially with the advent of genetic and proteomic testing approaches that rely on fresh or fresh frozen tissue. These approaches are part of the revolution in personalized medicine. This revolution’s impact on biorepositories—their mission and day-to-day function—will be profound. Direct patient care will require structuring tissue procurement to become a routine part of patient care. Accordingly tissue banking will expand from its traditional research role in large academic medical centers into the everyday practice of surgical pathology. Successful implementation of this model will require consideration of several financial, medicolegal, and administrative issues. PMID:22031304

Periodontal and peri-implant bone regeneration: clinical and histologic observations.

PubMed

Artzi, Z; Zohar, R; Tal, H

1997-02-01

The principle of guided tissue regeneration by barrier membranes to restore lost periodontal tissue around natural teeth has also been used around osseointegrated implants in an attempt to restore alveolar ridge defects. While most periodontal procedures in the literature describe root coverage by mucogingival surgery, which achieves healing through soft tissue attachment, regeneration of denuded root surfaces is performed by guided tissue regeneration using expanded polytetrafluoroethylene barrier membranes and demineralized freeze-dried bone allografts as inductive/conductive materials. In this study the technique is applied in two partially exposed cylindrical hydroxyapatite-coated implants in extraction sites in one patient. Surgical reentry in both sites is presented, with histologic examination revealing new bone formation on the exposed root surface and the hydroxyapatite-coated implants.

Mechanical behavior of peripheral stents and stent-vessel interaction: A computational study

NASA Astrophysics Data System (ADS)

Dottori, Serena; Flamini, Vittoria; Vairo, Giuseppe

2016-05-01

In this paper stents employed to treat peripheral artery disease are analyzed through a three-dimensional finite-element approach, based on a large-strain and large-displacement formulation. Aiming to evaluate the influence of some stent design parameters on stent mechanics and on the biomechanical interaction between stent and arterial wall, quasi-static and dynamic numerical analyses are carried out by referring to computational models of commercially and noncommercially available versions of both braided self-expandable stents and balloon-expandable stents. Addressing isolated device models, opening mechanisms and flexibility of both opened and closed stent configurations are numerically experienced. Moreover, stent deployment into a stenotic peripheral artery and possible postdilatation angioplasty (the latter for the self-expandable device only) are simulated by considering different idealized vessel geometries and accounting for the presence of a stenotic plaque. Proposed results highlight important differences in the mechanical response of the two types of stents, as well as a significant influence of the vessel shape on the stress distributions arising upon the artery-plaque system. Finally, computational results are used to assess both the stent mechanical performance and the effectiveness of the stenting treatment, allowing also to identify possible critical conditions affecting the risk of stent fracture, tissue damage, and/or pathological tissue response.

Disorganized collagen scaffold interferes with fibroblast mediated deposition of organized extracellular matrix in vitro.

PubMed

Saeidi, Nima; Guo, Xiaoqing; Hutcheon, Audrey E K; Sander, Edward A; Bale, Shyam Sundar; Melotti, Suzanna A; Zieske, James D; Trinkaus-Randall, Vickery; Ruberti, Jeffrey W

2012-10-01

Many tissue engineering applications require the remodeling of a degradable scaffold either in vitro or in situ. Although inefficient remodeling or failure to fully remodel the temporary matrix can result in a poor clinical outcome, very few investigations have examined in detail, the interaction of regenerative cells with temporary scaffoldings. In a recent series of investigations, randomly oriented collagen gels were directly implanted into human corneal pockets and followed for 24 months. The resulting remodeling response exhibited a high degree of variability which likely reflects differing regenerative/synthetic capacity across patients. Given this variability, we hypothesize that a disorganized, degradable provisional scaffold could be disruptive to a uniform, organized reconstruction of stromal matrix. In this investigation, two established corneal stroma tissue engineering culture systems (collagen scaffold-based and scaffold-free) were compared to determine if the presence of the disorganized collagen gel influenced matrix production and organizational control exerted by primary human corneal fibroblast cells (PHCFCs). PHCFCs were cultured on thin disorganized reconstituted collagen substrate (RCS--five donors: average age 34.4) or on a bare polycarbonate membrane (five donors: average age 32.4 controls). The organization and morphology of the two culture systems were compared over the long-term at 4, 8, and 11/12 weeks. Construct thickness and extracellular matrix organization/alignment was tracked optically with bright field and differential interference contrast (DIC) microscopy. The details of cell/matrix morphology and cell/matrix interaction were examined with standard transmission, cuprolinic blue and quick-freeze/deep-etch electron microscopy. Both the scaffold-free and the collagen-based scaffold cultures produced organized arrays of collagen fibrils. However, at all time points, the amount of organized cell-derived matrix in the scaffold-based constructs was significantly lower than that produced by scaffold-free constructs (controls). We also observed significant variability in the remodeling of RCS scaffold by PHCFCs. PHCFCs which penetrated the RCS scaffold did exert robust local control over secreted collagen but did not appear to globally reorganize the scaffold effectively in the time period of the study. Consistent with our hypothesis, the results demonstrate that the presence of the scaffold appears to interfere with the global organization of the cell-derived matrix. The production of highly organized local matrix by fibroblasts which penetrated the scaffold suggests that there is a mechanism which operates close to the cell membrane capable of controlling fibril organization. Nonetheless, the local control of the collagen alignment produced by cells within the scaffold was not continuous and did not result in overall global organization of the construct. Using a disorganized scaffold as a guide to produce highly organized tissue has the potential to delay the production of useful matrix or prevent uniform remodeling. The results of this study may shed light on the recent attempts to use disorganized collagenous matrix as a temporary corneal replacement in vivo which led to a variable remodeling response. Copyright © 2012 Wiley Periodicals, Inc.

Disorganized collagen scaffold interferes with fibroblast mediated deposition of organized extracellular matrix in vitro

PubMed Central

Saeidi, Nima; Guo, Xiaoqing; Hutcheon, Audrey E. K.; Sander, Edward A.; Bale, Shyam Sundar; Melotti, Suzanna A.; Zieske, James D.; Trinkaus-Randall, Vickery; Ruberti, Jeffrey W.

2013-01-01

Many tissue engineering applications require the remodeling of a degradable scaffold either in vitro or in situ. Although inefficient remodeling or failure to fully remodel the temporary matrix can result in a poor clinical outcome, very few investigations have examined in detail, the interaction of regenerative cells with temporary scaffoldings. In a recent series of investigations, randomly oriented collagen gels were directly implanted into human corneal pockets and followed for 24 months. The resulting remodeling response exhibited a high degree of variability which likely reflects differing regenerative/synthetic capacity across patients. Given this variability, we hypothesize that a disorganized, degradable provisional scaffold could be disruptive to a uniform, organized reconstruction of stromal matrix. In this investigation, two established corneal stroma tissue engineering culture systems (collagen scaffold-based and scaffold-free) were compared to determine if the presence of the disorganized collagen gel influenced matrix production and organizational control exerted by primary human corneal fibroblast cells (PHCFCs). PHCFCs were cultured on thin disorganized reconstituted collagen substrate (RCS - 5 donors: average age 34.4) or on a bare polycarbonate membrane (5 donors: average age 32.4-controls). The organization and morphology of the two culture systems were compared over the long-term at 4, 8 and 11/12 weeks. Construct thickness and extracellular matrix organization/alignment was tracked optically with bright field and differential interference contrast (DIC) microscopy. The details of cell/matrix morphology and cell/matrix interaction were examined with standard transmission, cuprolinic blue and quick-freeze/deep-etch electron microscopy. Both the scaffold-free and the collagen-based scaffold cultures produced organized arrays of collagen fibrils. However, at all time points, the amount of organized cell-derived matrix in the scaffold-based constructs was significantly lower than that produced by scaffold-free constructs (controls). We also observed significant variability in the remodeling of RCS scaffold by PHCFCs. PHCFCs which penetrated the RCS scaffold did exert robust local control over secreted collagen but did not appear to globally reorganize the scaffold effectively in the time period of the study. Consistent with our hypothesis, the results demonstrate that the presence of the scaffold appears to interfere with the global organization of the cell-derived matrix. The production of highly-organized local matrix by fibroblasts which penetrated the scaffold suggests that there is a mechanism which operates close to the cell membrane capable of control fibril organization. Nonetheless, the local control of the collagen alignment produced by cells within the scaffold was not continuous and did not result in overall global organization of the construct. Using a disorganized scaffold as a guide to produce highly-organized tissue has the potential to delay the production of useful matrix or prevent uniform remodeling. The results of this study may shed light on the recent attempts to use disorganized collagenous matrix as a temporary corneal replacement in vivo which led to a variable remodeling response. PMID:22528405

20 CFR 655.34 - Validity of temporary labor certifications.

Code of Federal Regulations, 2010 CFR

2010-04-01

... TEMPORARY EMPLOYMENT OF FOREIGN WORKERS IN THE UNITED STATES Labor Certification Process and Enforcement of Attestations for Temporary Employment in Occupations Other Than Agriculture or Registered Nursing in the United...

Return to Work After Temporary Disability Pension in Finland.

PubMed

Laaksonen, Mikko; Gould, Raija

2015-09-01

When it is possible that the employee's work ability can be restored through treatment or rehabilitation, disability pension in Finland is granted for a fixed period. We examined which factors are associated with return to work (RTW) after such temporary disability pension. The study included all Finnish residents whose temporary disability pension from the earnings-related pension system started in 2008 (N = 10,269). Competing risks regression analysis was applied to examine register-based determinants for RTW after temporary disability pension due to mental disorders, musculoskeletal diseases, other diseases, and injury over a 4-year follow-up period. The overall cumulative incidence of RTW was 25%. RTW was more probable after temporary disability pension due to injury and musculoskeletal diseases and less probable after temporary disability pension due to mental disorders. Younger age and higher education increased RTW but differences between genders, private and public sector employees, and occupational classes were relatively small. The probability of RTW was higher among those who were employed before their temporary disability pension (subhazard ratio in multivariate analysis 2.41 (95% CI 2.13-2.72) and among the 9% who participated in vocational rehabilitation during their pension [SHR 2.10 (95% CI 1.90-2.31)]. With some exceptions, the results were fairly similar for all diagnostic causes of temporary disability pension. Return to work after temporary disability pension was relatively uncommon. Nevertheless, in all diagnostic groups RTW continued for the whole follow-up period. The low educated and those not employed before temporary disability pension need more support in their RTW. The strong association between vocational rehabilitation and RTW suggests that increasing rehabilitation among those with impaired work ability may promote RTW.

From maternity to parental leave policies: women's health, employment, and child and family well-being.

PubMed

Kamerman, S B

2000-01-01

Pregnancy and maternity are increasingly viewed as social as well as individual risks that require health protection, employment protection and security, and protection against temporary loss of income. Begun more than a century ago in Germany, paid and job-protected maternity leaves from work were established in most countries initially out of concern for maternal and child physical health. Beginning in the 1960s, these policies have expanded to cover paternity and parental leaves following childbirth and adoption as well. Moreover, they have increasingly emerged as central to the emotional and psychological well-being of children as well as to the employment and economic security of their mothers and fathers. They are modest social policies, but are clearly an essential part of any country's child and family policy. No industrialized country today can be without such provision, and the United States is a distinct laggard in these developments.

Botulinum toxin in the treatment of vocal fold nodules.

PubMed

Allen, Jacqui E; Belafsky, Peter C

2009-12-01

Promising new techniques in the management of vocal fold nodules have been developed in the past 2 years. Simultaneously, the therapeutic use of botulinum toxin has rapidly expanded. This review explores the use of botulinum toxin in treatment of vocal nodules and summarizes current therapeutic concepts. New microsurgical instruments and techniques, refinements in laser technology, radiosurgical excision and steroid intralesional injections are all promising new techniques in the management of vocal nodules. Botulinum toxin-induced 'voice rest' is a new technique we have employed in patients with recalcitrant nodules. Successful resolution of nodules is possible with this technique, without the risk of vocal fold scarring inherent in dissection/excision techniques. Botulinum toxin usage is exponentially increasing, and large-scale, long-term studies demonstrate its safety profile. Targeted vocal fold temporary paralysis induced by botulinum toxin injection is a new, well tolerated and efficacious treatment in patients with persistent vocal fold nodules.